Glomerular filtration barrier in pediatric idiopathic nephrotic syndrome.

PubMed

Sharma, Alok; Gupta, Ruchika; Bagga, Arvind; Dinda, Amit K

2013-03-01

Nephrotic syndrome (NS) is a common proteinuric disorder with defect in the perm-selectivity of the glomerular filtration barrier (GFB). Ultrastructural morphometric evaluation of the GFB in pediatric NS has been attempted in only a few studies. This study was aimed at qualitative and quantitative evaluation of the alterations involving the GFB in pediatric idiopathic NS with an attempt to correlate these alterations with the clinico-laboratory data. For this study, renal biopsies from nine patients with NS and two children with interstitial nephritis were included. Relevant clinical and laboratory data, including degree of 24-h proteinuria and renal function tests, were recorded. Renal biopsies were reviewed for morphologic and electron microscopic diagnosis. Ultrastructural morphometry of the GFB was performed using image analysis software. The age at onset of NS, duration of illness, presence of hypertension, and renal function tests were comparable between the group of patients with minimal change disease (MCD) and those with mesangioproliferative glomerulonephritis (mesPGN)/focal segmental glomerulosclerosis (FSGS). However, the latter group showed higher 24-h proteinuria compared with the group with MCD. Among the detected ultra-structural changes, glomerular basement membrane thickness and foot process width were significantly different between the MCD and the mesPGN/FSGS groups. The slit pore diameter in the glomeruli showed a positive correlation with the degree of proteinuria. We conclude that our study demonstrated remarkable differences in certain parameters and the glomerular ultrastructural alterations in the various categories of NS. These differences might underlie the observed variation in response of these entities to various therapies.

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.

PubMed

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.

Heterogeneity of acute myeloblastic leukemia without maturation: an ultrastructural study.

PubMed

Hamamoto, K; Date, M; Taniguchi, H; Nagano, T; Kishimoto, Y; Kimura, T; Fukuhara, S

1995-01-01

We demonstrated by ultrastructural examination that the leukemic blasts of 13 patients with acute myeloblastic leukemia (AML) without maturation (M1 in the French-American-British classification) showed heterogeneous features. In 7 patients, the leukemic blasts had a high level of light microscopic myeloperoxidase positivity (> 50%). Ultrastructurally, the cells were myeloblast-promyelocytes with 100% myeloperoxidase positivity, and these 7 patients appeared to have typical AML. In contrast, the remaining 6 patients had leukemic blasts with a low myeloperoxidase positivity (< 50%) and heterogeneous features. Three had ultrastructural features of myelomonocytic or monocytic lineage, 1 had myelomonocytic cells associated with megakaryoblasts, and 1 had undifferentiated blasts. The former group had a better prognosis than the latter, indicating that ultrastructural analysis of M1 leukemia may help predict the response to therapy.

Comparative ultrastructure of fruit plastids in three genetically diverse genotypes of apple (Malus × domestica Borkh.) during development.

PubMed

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 biochemistry of plastids in perennial non-model systems.

Finite element modeling of hyper-viscoelasticity of peripheral nerve ultrastructures.

PubMed

Chang, Cheng-Tao; Chen, Yu-Hsing; Lin, Chou-Ching K; Ju, Ming-Shaung

2015-07-16

The mechanical characteristics of ultrastructures of rat sciatic nerves were investigated through animal experiments and finite element analyses. A custom-designed dynamic testing apparatus was used to conduct in vitro transverse compression experiments on the nerves. The optical coherence tomography (OCT) was utilized to record the cross-sectional images of nerve during the dynamic testing. Two-dimensional finite element models of the nerves were built based on their OCT images. A hyper-viscoelastic model was employed to describe the elastic and stress relaxation response of each ultrastructure of the nerve, namely the endoneurium, the perineurium and the epineurium. The first-order Ogden model was employed to describe the elasticity of each ultrastructure and a generalized Maxwell model for the relaxation. The inverse finite element analysis was used to estimate the material parameters of the ultrastructures. The results show the instantaneous shear modulus of the ultrastructures in decreasing order is perineurium, endoneurium, and epineurium. The FE model combined with the first-order Ogden model and the second-order Prony series is good enough for describing the compress-and-hold response of the nerve ultrastructures. The integration of OCT and the nonlinear finite element modeling may be applicable to study the viscoelasticity of peripheral nerve down to the ultrastructural level. Copyright © 2015 Elsevier Ltd. All rights reserved.

Peculiarities of ultrastructure of Chlorella cells growing aboard the Bion-10 during 12 days

NASA Astrophysics Data System (ADS)

Popova, A. F.; Sytnik, K. M.

The ultrastructure of Chlorella cells grown in darkness on a solid agar medium with organic additions aboard the Bion-1O biosatellite was studied. Certain differences in submicroscopic organization of organelles in the experimental cells were revealed compared to the Earth control. The changes are registered mainly in ultrastructure of energetic organelles - mitochondria and plastids of the experimental cells, in particular, an increase of mitochondria and their cristae size, as well as an increase of the total volume of mitochondrion per cell were established. The decrease of the starch amount in the plastid stroma and the electron density of the latter was also observed. In many experimental cells, the increase of condensed chromatin in the nuclei has been noted. Ultrastructural rearrangements in cells after laboratory experiment realized according to the thermogram registered aboard the Bion-10 were insignificant compared to the flight experiment. Data obtained are compared to results of space flight experiments carried out aboard the Bion-9 (polycomponent aquatic system) and the orbital station Mir (solid agar medium).

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

PubMed

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.

PubMed

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 extracellular matrix partial digestion to address significant gaps in understanding of disc microstructure and will contribute to multidisciplinary ultrastructure-function studies. Visualization of the intra-lamellar matrix under high magnification revealed a dense network of elastic fibers that has not been previously described. The present study used extracellular matrix partial digestion to address significant gaps in understanding of disc microstructure and will contribute to multidisciplinary ultrastructure-function studies. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Ultrastructural hepatocellular features associated with severe hepatic lipidosis in cats.

PubMed

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.

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

PubMed

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.

Negative Staining for COL4A5 Correlates With Worse Prognosis and More Severe Ultrastructural Alterations in Males With Alport Syndrome.

PubMed

Said, Samar M; Fidler, Mary E; Valeri, Anthony M; McCann, Brooke; Fiedler, Wade; Cornell, Lynn D; Alexander, Mariam Priya; Alkhunaizi, Ahmed M; Sullivan, Anne; Cramer, Carl H; Hogan, Marie C; Nasr, Samih H

2017-01-01

Alport syndrome (AS) is a genetic disorder characterized by progressive hematuric nephropathy with or without sensorineural hearing loss and ocular lesions. Previous studies on AS included mostly children. To determine the prognostic value of loss of staining for collagen type IV alpha 5 (COL4A5) and its relationship with the ultrastructural glomerular basement membrane alterations, we performed direct immunofluorescence using a mixture of fluorescein isothiocyanate-conjugated and Texas-red conjugated antibodies against COL4A5 and COL4A2, respectively, on renal biopsies of 25 males with AS (including 16 who were diagnosed in adulthood). All patients showed normal positive staining of glomerular basement membranes and tubular basement membranes for COL4A2. Of the 25 patients, 10 (40%) patients showed loss of staining for COL4A5 (including 89% of children and 13% of adults) and the remaining 15 (60%) had intact staining for COL4A5. Compared with patients with intact staining for COL4A5, those with loss of staining had more prominent ultrastructural glomerular basement membrane alterations and were younger at the time of biopsy. By Kaplan-Meier survival analysis and Cox regression analysis, loss of staining for COL4A5 predicted earlier progression to overt proteinuria and stage 2 chronic kidney disease or worse. By multivariate Cox regression analysis, loss of staining for COL4A5 was an independent predictor of the development of overt proteinuria and stage 2 chronic kidney disease or worse. Thus, the COL4A5 expression pattern has an important prognostic value and it correlates with the severity of ultrastructural glomerular basement membrane alterations in males with AS. Loss of COL4A5 staining is uncommon in patients with AS diagnosed in their adulthood.

Electron microscopy for ultrastructural analysis and protein localization in Saccharomyces cerevisiae

PubMed Central

Frankl, Andri; Mari, Muriel; Reggiori, Fulvio

2015-01-01

The yeast Saccharomyces cerevisiae is a key model system for studying of a multitude of cellular processes because of its amenability to genetics, molecular biology and biochemical procedures. Ultrastructural examinations of this organism, though, are traditionally difficult because of the presence of a thick cell wall and the high density of cytoplasmic proteins. A series of recent methodological and technical developments, however, has revived interest in morphological analyses of yeast (e.g. 123). Here we present a review of established and new methods, from sample preparation to imaging, for the ultrastructural analysis of S. cerevisiae. We include information for the use of different fixation methods, embedding procedures, approaches for contrast enhancement, and sample visualization techniques, with references to successful examples. The goal of this review is to guide researchers that want to investigate a particular process at the ultrastructural level in yeast by aiding in the selection of the most appropriate approach to visualize a specific structure or subcellular compartment. PMID:28357267

Ultrastructure of canine vasoformative tumors.

PubMed

Madewell, B R; Griffey, S M; Munn, R J

1992-01-01

The transmission electron microscope was used to examine 20 spontaneous canine hemangiosarcomas or hemangiopericytomas in order to define their fine ultrastructural features, and to compare those features with descriptions of human counterpart neoplasms. From specimen to specimen the neoplasms examined showed considerable structural heterogeneity but, in composite, appeared similar to the prototype human tumors. These data suggest that the canine hemangiosarcoma and hemangiopericytoma might serve as comparative models for studies of the morphogenesis of vasoformative neoplasms.

Effect of ammonium hydroxide on ultrastructure and tenderness of buffalo meat.

PubMed

Naveena, B M; Kiran, M; Reddy, K Sudhakar; Ramakrishna, C; Vaithiyanathan, S; Devatkal, Suresh K

2011-08-01

This study was conducted with an objective to improve the tenderness of tough buffalo meat using ammonium hydroxide. Buffalo meat chunks from Biceps femoris muscle were marinated with distilled water (control), 0.1%, 0.5% and 1.0% solution of ammonium hydroxide for 48 h at 4±1 °C and subjected to various physico-chemical analysis and ultrastructural studies. Ammonium hydroxide increased (P<0.05) the pH, water holding capacity (WHC), collagen solubility, total and salt soluble protein extractability and cooking yield. Reduction (P<0.05) in Warner-Bratzler shear force values were observed in all ammonium hydroxide treated samples compared to non-treated control. Electrophoretic pattern of muscle proteins exhibited reduction in the intensity and number of certain protein bands for 0.1% and 0.5% ammonium hydroxide treated samples compared to control. Scanning and transmission electron microscopy also revealed breakdown of endothelium layers surrounding muscle fibers and weakening of Z-discs respectively, in treated samples compared to controls. These results suggest that ammonium hydroxide might be used to tenderize tough buffalo meat. Copyright © 2011 Elsevier Ltd. All rights reserved.

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

PubMed Central

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

Confocal laser scanning microscopic photoconversion: a new method to stabilize fluorescently labeled cellular elements for electron microscopic analysis.

PubMed

Colello, Raymond J; Tozer, Jordan; Henderson, Scott C

2012-01-01

Photoconversion, the method by which a fluorescent dye is transformed into a stable, osmiophilic product that can be visualized by electron microscopy, is the most widely used method to enable the ultrastructural analysis of fluorescently labeled cellular structures. Nevertheless, the conventional method of photoconversion using widefield fluorescence microscopy requires long reaction times and results in low-resolution cell targeting. Accordingly, we have developed a photoconversion method that ameliorates these limitations by adapting confocal laser scanning microscopy to the procedure. We have found that this method greatly reduces photoconversion times, as compared to conventional wide field microscopy. Moreover, region-of-interest scanning capabilities of a confocal microscope facilitate the targeting of the photoconversion process to individual cellular or subcellular elements within a fluorescent field. This reduces the area of the cell exposed to light energy, thereby reducing the ultrastructural damage common to this process when widefield microscopes are employed. © 2012 by John Wiley & Sons, Inc.

X-ray metal assessment and ovarian ultrastructure alterations of the beetle, Blaps polycresta (Coleoptera, Tenebrionidae), inhabiting polluted soil.

PubMed

Osman, Wafaa; Shonouda, Mourad

2017-06-01

X-ray analysis was applied to estimate the percentages of heavy metals in ovarian tissues of the tenebrionid beetle, Blaps polycresta. Calcium, phosphorus, sulfur, cadmium, copper, and zinc were the most common detected metals in ovaries of insects collected from reference and polluted sites. Only cadmium showed significantly higher percentages in the polluted ovaries compared with the reference ones. Ultrastructure investigation revealed severe alterations in polluted ovaries both in the tropharium and in the vitellarium. Contraction of nuclear membrane of trophocytes was observed; therefore, cavities and spaces appeared in the cytoplasm followed by nuclear pyknosis. In the vitellarium, fragmentation of chromatin materials in nuclei of the follicular cells was detected. The cytoplasm was poor in the rough endoplasmic reticulum and mitochondria. Damage of yolk bodies occurred in addition to break off in the layer of microvilli. Accumulation of electron-dense vesicles and multivesicular bodies were observed in both reference and polluted ovaries. These alterations in ovarian ultrastructure of B. polycresta show the severe impact of cadmium pollution on cell organelles of insects and could be used as an interesting tool for monitoring heavy metals inside the body organs due to soil pollution.

Where are the sensory organs of Nybelinia surmenicola (Trypanorhyncha)? A comparative analysis with Parachristianella sp. and other trypanorhynchean cestodes.

PubMed

Biserova, Natalia M; Gordeev, Ilya I; Korneva, Janetta V

2016-01-01

The sensory organs in tegument of two trypanorhynchean species--Nybelinia surmenicola (plerocercoid) and adult Parachristianella sp. (Cestoda, Trypanorhyncha)--were studied with the aim of ultrastructural description and a comparative analysis. The Nybelinia surmenicola plerocercoid lacks papillae with sensory cilia on the bothria adhesive surface. We found an unciliated sensory organ within the median bothria fold. This unciliated free nerve ending contains the central electron-dense disc, three dense supporting rings, and broad root. The nerve ending locates in the basal matrix under the tegument. The tegument of N. surmenicola has a number of ultrastructural features which make it significantly different from other Trypanorhyncha: (i) the tegumental cytoplasm has a plicated constitution in a form of high apical and deep basal folds, (ii) numerous layers of the basal matrix are presented in the subtegument, and (iii) the squamiform and bristlelike microtriches N. surmenicola lack the base and the basal plate. In contrast, numerous ciliated and unciliated receptors were found in Parachristianella sp.: six types on the bothria and one type in the strobila tegument. Ultrastructural constitution of sensory organs in the form of ciliated free nerve endings as well as unciliated basal nerve endings of Parachristianella sp. has many common features inside Eucestoda. In comparison with other Trypanorhyncha, all Nybelinia species studied have less quantity of the bothrial sensory organs. This fact may reflect behavioral patterns of Nybelinia as well as phylogenetic position into Trypanorhyncha. Our observations of living animals conventionally demonstrate the ability of N. surmenicola plerocercoids to locomote in forward direction on the Petri dish surface. The participation of the bothrial microtriches in a parasite movement has been discussed.

Ultrastructure and morphogenesis of the wing scales in Heliconius erato phyllis (Lepidoptera: Nymphalidae): what silvery/brownish surfaces can tell us about the development of color patterning?

PubMed

Aymone, A C B; Valente, V L S; de Araújo, A M

2013-09-01

Usually the literature on Heliconius show three types of scales, classified based on the correlation between color and ultrastructure: type I - white and yellow, type II - black, and type III - orange and red. The ultrastructure of the scales located at the silvery/brownish surfaces of males/females is for the first time described in this paper. Besides, we describe the ontogeny of pigmentation, the scale morphogenesis and the maturation timing of scales fated to different colors in Heliconius erato phyllis. The silvery/brownish surfaces showed ultrastructurally similar scales to the type I, II and III. The ontogeny of pigmentation follows the sequence red, black, silvery/brownish and yellow. The maturation of yellow-fated scales, however, occurred simultaneously with the red-fated scales, before the pigmentation becomes visible. In spite of the scales at the silvery/brownish surfaces being ultrastructurally similar to the yellow, red and black scales, they mature after them; this suggests that the maturation timing does not show a relationship with the scale ultrastructure, with the deposition timing of the yellow pigment. The analysis of H. erato phyllis scale morphogenesis, as well as the scales ultrastructure and maturation timing, provided new findings into the developmental architecture of color pattern in Heliconius. Copyright © 2013 Elsevier Ltd. All rights reserved.

Brenner tumor of the ovary: a correlative histologic, histochemical, immunohistochemical, and ultrastructural investigation.

PubMed

Santini, D; Gelli, M C; Mazzoleni, G; Ricci, M; Severi, B; Pasquinelli, G; Pelusi, G; Martinelli, G

1989-08-01

The histologic, histochemical, immunohistochemical, and ultrastructural features of Brenner tumor (BT) were studied. BT was compared with transitional bladder cells, and close similarities between the two tissues were identified. Abundant glycogen in all cellular layers, an alcianophilic/sialomucinic surface mucous coat, and argyrophilic cells characterized both BT and bladder epithelium. Immunohistochemically, chromogranin and neuron-specific enolase reactivity was observed in all cases examined. An additional relevant finding was the presence of serotonin-storing cells in both BT and urothelium. Moreover, carcinoembryonic antigen, epithelial membrane antigen, and keratin reaction were found in BT and urothelium, indicating an additional antigenic similarity. Additionally, malignant Brenner tumor was ultrastructurally found to share many common features with the bladder tissue. The distinct histochemical, ultrastructural, and antigenic pattern of BT, primarily of the transitional type, is emphasized.

Freezing solution containing dimethylsulfoxide and fetal calf serum maintains survival and ultrastructure of goat preantral follicles after cryopreservation and in vitro culture of ovarian tissue.

PubMed

Castro, Simone Vieira; de Carvalho, Adeline Andrade; da Silva, Cleidson Manoel Gomes; Faustino, Luciana Rocha; Campello, Cláudio Cabral; Lucci, Carolina Madeira; Báo, Sônia Nair; de Figueiredo, José Ricardo; Rodrigues, Ana Paula Ribeiro

2011-11-01

Goat ovarian cortex fragments were subjected to slow freezing in the presence of various solutions containing intracellular cryoprotectants, including 1.0 M ethylene glycol (EG), propanediol (PROH), or dimethyl sulfoxide (DMSO), with or without sucrose and/or fetal calf serum (FCS). Histological examination revealed that only the DMSO-containing solutions were able to maintain a follicular ultrastructure similar to the morphology observed in the fresh control. Therefore, fragments previously cryopreserved in DMSO solutions (with and without sucrose and/or FCS) were cultured in vitro for 48 h and then subjected to viability, histological, and ultrastructural analysis. No significant differences were observed among the percentages of morphologically normal follicles in cryopreserved ovarian tissue before in vitro culture (DMSO: 62.5%; DMSO + sucrose: 68.3%; DMSO + FCS: 60.0%; DMSO + sucrose + FCS: 60.0%) and after culture (DMSO: 60.8%; DMSO + sucrose: 64.2%; DMSO + FCS: 70.8%; DMSO + sucrose + FCS: 55.0%). Following in vitro culture, the viability analysis showed that only the freezing solution containing DMSO and FCS (75.6%) maintained a percentage of viable follicles similar to that observed after culture without cryopreservation (89.3%). As determined by ultrastructural analysis, morphologically normal preantral follicles were detected in the fresh control and in fragments cultured before and after cryopreservation with DMSO and FCS. Thus, a freezing solution containing DMSO and FCS, under the experimental conditions tested here, guaranteed the maintenance of viability and follicular ultrastructure after short-term in vitro culture.

Flight duration and flight muscle ultrastructure of unfed hawk moths.

PubMed

Wone, Bernard W M; Pathak, Jaika; Davidowitz, Goggy

2018-06-13

Flight muscle breakdown has been reported for many orders of insects, but the basis of this breakdown in insects with lifelong dependence on flight is less clear. Lepidopterans show such muscle changes across their lifespans, yet how this change affects the ability of these insects to complete their life cycles is not well documented. We investigated the changes in muscle function and ultrastructure of unfed aging adult hawk moths (Manduca sexta). Flight duration was examined in young, middle-aged, and advanced-aged unfed moths. After measurement of flight duration, the main flight muscle (dorsolongitudinal muscle) was collected and histologically prepared for transmission electron microscopy to compare several measurements of muscle ultrastructure among moths of different ages. Muscle function assays revealed significant positive correlations between muscle ultrastructure and flight distance that were greatest in middle-aged moths and least in young moths. In addition, changes in flight muscle ultrastructure were detected across treatment groups. The number of mitochondria in muscle cells peaked in middle-aged moths. Many wild M. sexta do not feed as adults; thus, understanding the changes in flight capacity and muscle ultrastructure in unfed moths provides a more complete understanding of the ecophysiology and resource allocation strategies of this species. Copyright © 2018 Elsevier Ltd. All rights reserved.

Reptilian spermatogenesis

PubMed Central

2011-01-01

Until recently, the histology and ultrastructural events of spermatogenesis in reptiles were relatively unknown. Most of the available morphological information focuses on specific stages of spermatogenesis, spermiogenesis, and/or of the mature spermatozoa. No study to date has provided complete ultrastructural information on the early events of spermatogenesis, proliferation and meiosis in class Reptilia. Furthermore, no comprehensive data set exists that describes the ultrastructure of the entire ontogenic progression of germ cells through the phases of reptilian spermatogenesis (mitosis, meiosis and spermiogenesis). The purpose of this review is to provide an ultrastructural and histological atlas of spermatogenesis in reptiles. The morphological details provided here are the first of their kind and can hopefully provide histological information on spermatogenesis that can be compared to that already known for anamniotes (fish and amphibians), birds and mammals. The data supplied in this review will provide a basic model that can be utilized for the study of sperm development in other reptiles. The use of such an atlas will hopefully stimulate more interest in collecting histological and ultrastructural data sets on spermatogenesis that may play important roles in future nontraditional phylogenetic analyses and histopathological studies in reptiles. PMID:22319673

Effect of unilateral extraction of molar teeth on suprahyoid muscles: macroscopic and ultrastructural aspects.

PubMed

Iyomasa, Mamie Mizusaki; Issa, João Paulo Mardegan; Siéssere, Selma; Regalo, Simone Cecílio Hallak; Watanabe, Ii-sei

2008-12-01

Anatomical and physiologic components are parts of the stomatognathic system and their interaction results in integrated functional activities. Important alterations in the masticatory system originated by dental loss affect the bone, oral mucosa and muscular function. Dental arch structures specifically designed to receive and expose teeth allow performance of their functions. But the distinction between bony and soft tissues is lost when teeth are removed since there is not a specific function to be completed. The aim of this study was to evaluate the macroscopic and ultrastructural effects of the unilateral extraction of molar teeth on the suprahyoid muscles function, using twenty young male gerbils (Meriones unguiculatus) as the experimental animal model. They were divided in experimental malocclusion (n=10) and control (n=10) groups. The experimental malocclusion group was submitted to exodontia of the left upper molars and the control group was not submitted to this procedure and served as sham-operated. For macroscopic analysis of the suprahyoid muscle, the skin was uplifted and the muscles dissected individually and removed for weight analysis according to Scherle method. The electron microscopy analysis was made in ultra thin sections of small suprahyoid muscle fragments from the experimental and control groups, examined in a Jeol 1010, 880 Kv transmission electron microscope. Several micrographs at magnifications of 3000x, 6000x, 30,000x were randomly selected for the qualitative analysis of the muscle fiber ultrastructures. Sixty days after the induced unilateral occlusal alteration no macroscopic morphologic changes was detected in the suprahyoid muscles and the muscle volume differences between the right and left sides and between groups were not significant. However, in the ultrastructural analysis suprahyoid muscles showed characteristics of specific adaptation to the unilateral occlusal alteration, by the reduced density of subsarcolemmal mitochondria and the shorter and less numerous ramifications in intermyofibrilar mitochondria localized between electronlucid myofibrils. It is concluded that unilateral exodontia of all the upper left molars affect the ultrastructural morphology of suprahyoid muscle fibers.

The ultrastructural characteristics of porcine hepatocytes donated after cardiac death and preserved with warm machine perfusion preservation.

PubMed

Bochimoto, Hiroki; Matsuno, Naoto; Ishihara, Yo; Shonaka, Tatsuya; Koga, Daisuke; Hira, Yoshiki; Nishikawa, Yuji; Furukawa, Hiroyuki; Watanabe, Tsuyoshi

2017-01-01

The effects of warm machine perfusion preservation of liver grafts donated after cardiac death on the intracellular three-dimensional ultrastructure of the organelles in hepatocytes remain unclear. Here we analyzed comparatively the ultrastructure of the endomembrane systems in porcine hepatocytes under warm ischemia and successive hypothermic and midthermic machine perfusion preservation, a type of the warm machine perfusion. Porcine liver grafts which had a warm ischemia time of 60 minutes were perfused for 4 hours with modified University of Wisconsin gluconate solution. Group A grafts were preserved with hypothermic machine perfusion preservation at 8°C constantly for 4 hours. Group B grafts were preserved with rewarming up to 22°C by warm machine perfusion preservation for 4 hours. An analysis of hepatocytes after 60 minutes of warm ischemia by scanning electron microscope revealed the appearance of abnormal vacuoles and invagination of mitochondria. In the hepatocytes preserved by subsequent hypothermic machine perfusion preservation, strongly swollen mitochondria were observed. In contrast, the warm machine perfusion preservation could preserve the functional appearance of mitochondria in hepatocytes. Furthermore, abundant vacuoles and membranous structures sequestrating cellular organelles like autophagic vacuoles were frequently observed in hepatocytes after warm machine perfusion preservation. In conclusion, the ultrastructure of the endomembrane systems in the hepatocytes of liver grafts changed in accordance with the temperature conditions of machine perfusion preservation. In addition, temperature condition of the machine perfusion preservation may also affect the condition of the hepatic graft attributed to autophagy systems, and consequently alleviate the damage of the hepatocytes.

Ultrastructure of the root cap of Arabidopsis Thaliana L. Heynh under spaceflight conditions

NASA Technical Reports Server (NTRS)

1983-01-01

Peculiarities of the ultrastructural organization of Arabidopsis root cap cells grown from the stage of two cotyledonous leaves in the Svetoblok-1 apparatus aboard the Salyut 6 research orbital station and in the laboratory are assessed. It is established that under conditions of real space flight vacuolization of the root cap cells increses considerably compared to the control variant. Changes in the topography and ulstrastructure of amyloplasts as well as lysis of cell walls are observed in the material under study. An assumption is advanced on analogous cell responses observed at the ultrastructural level to weightlessness and clinostatic conditions.

Microwave Processing for Sample Preparation to Evaluate Mitochondrial Ultrastructural Damage in Hemorrhagic Shock

NASA Astrophysics Data System (ADS)

Josephsen, Gary D.; Josephsen, Kelly A.; Beilman, Greg J.; Taylor, Jodie H.; Muiler, Kristine E.

2005-12-01

This is a report of the adaptation of microwave processing in the preparation of liver biopsies for transmission electron microscopy (TEM) to examine ultrastructural damage of mitochondria in the setting of metabolic stress. Hemorrhagic shock was induced in pigs via 35% total blood volume bleed and a 90-min period of shock followed by resuscitation. Hepatic biopsies were collected before shock and after resuscitation. Following collection, biopsies were processed for TEM by a rapid method involving microwave irradiation (Giberson, 2001). Samples pre- and postshock of each of two animals were viewed and scored using the mitochondrial ultrastructure scoring system (Crouser et al., 2002), a system used to quantify the severity of ultrastructural damage during shock. Results showed evidence of increased ultrastructural damage in the postshock samples, which scored 4.00 and 3.42, versus their preshock controls, which scored 1.18 and 1.27. The results of this analysis were similar to those obtained in another model of shock (Crouser et al., 2002). However, the amount of time used to process the samples was significantly shortened with methods involving microwave irradiation.

Comparative study on antifungal activities of chitosan nanoparticles and chitosan silver nano composites against Fusarium oxysporum species complex.

PubMed

Dananjaya, S H S; Erandani, W K C U; Kim, Cheol-Hee; Nikapitiya, Chamilani; Lee, Jehee; De Zoysa, Mahanama

2017-12-01

Though the metal nanoparticles (NPs) have been shown favorable results against fungal diseases, erratic environmental toxicity of NPs have raised serious concerns against their applications. Hence, it is vital to modify antifungal compounds into safe substitutes over synthetic chemicals. In this study, antifungal effects of chitosan nanoparticles (CNPs) and chitosan silver nanocomposites (CAgNCs) were compared against Fusarium oxysporum species complex. CNPs and CAgNCs were synthesized, characterized and compared based on the transmission electron microscope, X-ray diffraction, UV-vis absorbance spectra, particle size distribution, zeta potential and thermal stability analysis. Ultra-structural analysis on mycelium membrane of treated F. oxysporum showed that CNPs and CAgNCs could induce a pronounced membrane damage and disruption of the mycelium surface, increase the membrane permeability, and even cell disintegration. CAgNCs showed a significantly higher radial growth inhibition than CNPs in all the tested concentrations. Both CNPs and CAgNCs were not only effective in reducing the fungal growth, but also caused morphological and ultrastructural changes in the pathogen, thereby suggesting its usage as an antifungal dispersion system to control F. oxysporum. Additionally, CNPs and CAgNCs therapy reduced the F. oxysporum infection in zebrafish. Data demonstrates biologically active CNPs and CAgNCs are promising antifungal agents against F. oxysporum. Copyright © 2017 Elsevier B.V. All rights reserved.

Brenner tumor of the ovary: a comparative immunohistochemical and ultrastructural study with transitional cell carcinoma of the bladder.

PubMed

Ordóñez, N G; Mackay, B

2000-01-01

Because of a fancied light microscopic resemblance to transitional epithelium (urothelium), Brenner tumor (BT) of the ovary is commonly described as a transitional cell neoplasm. An inability to detect a great deal of similarity between the two at the ultrastructural level prompted this electron microscopic study comparing 3 benign Brenner tumors with normal urothelium and 6 transitional cell carcinomas (TCC) of varying histologic grade from the urinary bladder. To complement the ultrastructural observations, the immunophenotype of 8 benign BTs was evaluated together with that of 12 TCCs of the bladder using antibodies to thrombomodulin (TM), cytokeratin 20, cytokeratin 7, and carcinoembryonic antigen (CEA), all of which have been shown to react with TCCs of urothelial origin. At the ultrastructural level, there was only limited evidence of a morphologic likeness between the epithelial cells of BTs and those of the benign or neoplastic urothelium. The immunophenotype of the two tumors also differed significantly in that there was no reactivity for TM or cytokeratin 20 in the BTs, while these markers were expressed in the TCCs. Both BTs and TCCs were positive for cytokeratin 7 and may express CEA.

Ultrastructural studies on the boundary tissue of the seminiferous tubules of different mammals.

PubMed

Cieciura, L; Jaszczuk-Jarosz, B; Pietrzkowska, K

1988-01-01

The aims of our studies were to compare the ultrastructure of the boundary tissue of seminiferous tubules of various mammals (rat, mouse, hamster, guinea pig, rabbit, ram, bull and man). Visual analysis of electron micrographs revealed the similarity of structure of all layers at investigated animals. The boundary tissue consists of 4 layers: 1) amorphous inner lamina, 2) cellular inner lamina, 3) amorphous outer lamina, 4) cellular outer lamina. The outer lamina of boundary tissue of rat, mouse and hamster revealed in histochemical reactions meshes resembling honey-combs. The wall of seminiferous canalicules of bull and ram consists of more bigger and different structure than one at the other laboratory animals. The most different structure of boundary tissue in man was observed. The capillary vessels penetrate in the myofibroblastic layer, when comparted to that found in other mammals on the surface of the wall.

Defective enamel ultrastructure in diabetic rodents.

PubMed

Atar, M; Atar-Zwillenberg, D R; Verry, P; Spornitz, U M

2004-07-01

We investigated six different types of diabetic rodents. Four expressed a genetic obesity resulting in diabetes. One developed diabetes induced by a diet-dependent obesity, and one with genetic diabetes received anti-diabetic medication. The tooth samples were examined under a scanning electron microscope and with an energy dispersive microanalysis (EDX). The electron micrographs showed severe, varying degrees of damage within the six different diabetic animal types, such as irregular crystallite deposition and prism perforations in genetically obese animals compared to less-disordered prism structures in diet-dependent obesity. Anti-diabetic medication resulted in normal enamel ultrastructure. The EDX analysis revealed a reduction in the amount of calcium and phosphorus in all regions affected by diabetes. Based on these animal studies, we suggest that both juvenile diabetes type I (in infants) and adult diabetes type II (in pregnant mothers, affecting the developing foetus) may affect the normal development of teeth in humans.

Endocrine cells in human Bartholin's glands. An immunohistochemical and ultrastructural analysis.

PubMed

Fetissof, F; Arbeille, B; Bellet, D; Barre, I; Lansac, J

1989-01-01

Endocrine cells were investigated in human Bartholin's glands by use of histochemical, immunohistochemical and ultrastructural methods. Endocrine cells represent normal constituents of these glands, being mainly distributed throughout the transitional epithelium of the major excretory duct; however, single elements are dispersed among the acinar lobules. Serotonin-, calcitonin-, katacalcin-, bombesin- and alpha-hCG-immunoreactive cells were recognized, with serotonin-immunoreactive cells predominating. Co-expression of calcitonin, katacalcin or alpha-hCG with serotonin was observed in single endocrine cells. At the ultrastructural level, these cells are richly granulated and show typical neuroendocrine features. Bartholin's glands display an endocrine profile quite similar to that of other cloacal-derived tissues.

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

PubMed

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 < 0.05. OSCC, Individual cell modifications, intercellular relationships and surface characteristics observed by scanning electron microscopy between OSCC, tobacco smokers, 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.

Bisphenol A-induced ultrastructural changes in the testes of common marmoset.

PubMed

Vijaykumar, Tushara; Singh, Dipty; Vanage, Geeta R; Dhumal, Rohit V; Dighe, Vikas D

2017-07-01

Bisphenol A (BPA) is an endocrine disruptor that is widely used in the manufacture of polycarbonate plastics, epoxy resins and dental sealants. It is known to have adverse effects on spermatogenesis in rodents. This study was aimed to evaluate the effects of BPA in adult common marmoset owing to its similarities with human spermatogenesis. Sixteen marmosets were divided into four groups (n=4 per group) and given oral doses of BPA (2.5, 12.5 and 25 μg/kg BW/day) for 70 days to cover two spermatogenic cycles, and the control group received only vehicle (honey). Testes were processed for histological and transmission electron microscopy studies. Histology of the testis showed sloughing of germ cells into the lumen, increase in interstitial space and vacuolation of Sertoli cell cytoplasm. Ultrastructural analysis of the testis revealed several degenerative effects on the basement membrane, Sertoli cells, Leydig cells and other developing germ cells in the 12.5 and 25 μg/kg BW/day groups as compared to control. The observed ultrastructural changes caused by BPA in testicular morphology might be indicative of a perturbed sperm production. Considering the genetic and spermatogenic similarities of common marmoset (Callithrix jacchus) and humans, the study findings are of significance. Further studies are, however, needed to elucidate the mechanism of action.

Quantitative Imaging of Scattering Changes Associated With Epithelial Proliferation, Necrosis and Fibrosis in Tumors Using Microsampling Reflectance Spectroscopy

PubMed Central

Krishnaswamy, Venkataramanan; Hoopes, P. Jack; Samkoe, Kimberley S.; O'Hara, Julia A.; Hasan, Tayyaba; Pogue, Brian W.

2010-01-01

Highly localized reflectance measurements can be used to directly quantify scatter changes in tissues. This study presents a microsampling approach that is used to raster scan tumors to extract parameters believed to be related to the tissue ultra-structure. A confocal reflectance imager was developed to examine scatter changes across pathologically distinct regions within tumor tissues. Tissue sections from two murine tumors, AsPC-1 pancreas tumor and the Mat-LyLu Dunning prostate tumor, were imaged. After imaging, histopathology-guided region-of-interest studies of the images allowed analysis of the variations in scattering resulting from differences in tissue ultra-structure. On average, the median scatter power of tumor cells with high proliferation index was about 26% less compared to tumor cells with low proliferation index (LPI). Necrosis exhibited the lowest scatter power signature across all the tissue types considered, with about 55% lower median scatter power than LPI tumor cells. Additionally, the level and maturity of the tumor's fibroplastic response was found to influence the scatter signal. This approach to scatter visualization of tissue ultra-structure in situ could provide a unique tool for guiding surgical resection, but this kind of interpretation into what the signal means relative to the pathology is required before proceeding to clinical studies. PMID:19256692

Syncytial Hepatitis of Tilapia ( Oreochromis niloticus L.) is Associated With Orthomyxovirus-Like Virions in Hepatocytes.

PubMed

Del-Pozo, J; Mishra, N; Kabuusu, R; Cheetham, S; Eldar, A; Bacharach, E; Lipkin, W I; Ferguson, H W

2017-01-01

Using transmission electron microscopy (TEM), the presented work expands on the ultrastructural findings of an earlier report on "syncytial hepatitis," a novel disease of tilapia (SHT). Briefly, TEM confirmed the presence of an orthomyxovirus-like virus within the diseased hepatocytes but not within the endothelium. This was supported by observing extracellular and intracellular (mostly intraendosomal), 60-100 nm round virions with a trilaminar capsid containing up to 7 electron-dense aggregates. Other patterns noted included enveloped or filamentous virions and virion-containing cytoplasmic membrane folds, suggestive of endocytosis. Patterns atypical for orthymyxovirus included the formation of syncytia and the presence of virions within the perinuclear cisternae (suspected to be the Golgi apparatus). The ultrastructural morphology of SHT-associated virions is similar to that previously reported for tilapia lake virus (TiLV). A genetic homology was investigated using the available reverse transcriptase polymerase chain reaction (RT-PCR) probes for TiLV and comparing clinically sick with clinically normal fish and negative controls. By RT-PCR analysis, viral nucleic acid was detected only in diseased fish. Taken together, these findings strongly suggest that a virus is causally associated with SHT, that this virus shares ultrastructural features with orthomyxoviruses, and it presents with partial genetic homology with TiLV (190 nucleotides).

[Effects of infrasound therapy on proliferation, apoptosis and ultrastructure of human B lymphoma Raji cells].

PubMed

Bao, Yong; Fan, Jian-Zhong; Li, Ke; Li, Chuan; Yang, Jun-Feng

2008-06-01

To investigate the effect of infrasound therapy on the proliferation, apoptosis and ultrastructure of human B lymphoma Raji cells. Human B lymphoma Raji cells were exposed to infrasound treatment for 15, 30, 60, 90 and 120 min and cultured subsequently for 24 or 48 h. MTT assay, flow cytometry analysis, and electron microscopy were performed to examine the proliferative status, cell apoptosis and ultrastructural changes of the exposed cells, respectively. MTT assay revealed no significant changes in the proliferation of the cells exposed to infrasound treatment (P>0.05), nor did flow cytometry analysis identified significant variation in the cell apoptosis (P>0.05). Scanning electron microscopy, however, identified shortened or reduced cell processes and microvilli on the surface of the cells with infrasound exposure and a subsequent 24-hour culture, and the cell membrane surface became smooth. Under transmission electron microscope, the cells with infrasound treatment presented with significantly reduced microvilli, and the cell nuclei appeared homogeneous, with cytoplasmic budding and losses after a 48-hour culture. Infrasound less than 90 dB does not obviously affect the proliferation and apoptosis of Raji cells, but may directly cause cell ultrastructural changes such as reduction of the cell processes.

Electron microscopic examination of the anterior lens capsule in a case of Alport's syndrome.

PubMed

Citirik, Mehmet; Batman, Cosar; Men, Gamze; Tuncel, Murvet; Zilelioglu, Orhan

2007-09-01

To report a case of Alport's syndrome and to present electronmicroscopic examination findings of the anterior lens capsule of this patient. A 21-year-old man was referred for low visual acuity and retinal pigment epithelial changes in the left eye. The patient and his relatives underwent detailed ophthalmological examination, including electrophysiological testing. The patient also underwent electronmicroscopic examination of the anterior lens capsule. His visual acuity was 6/18 OD and 6/15 OS. Anterior lenticonus and subcapsular opacities were observed in the left eye. Cataract extraction by phacoemulsification with intraocular lens implantation was performed for his poor visual performance. During the capsulorhexis, the remarkably thin and fragile anterior capsule was noted and removed. Ultrastructural analysis of the anterior lens capsule showed a thinner central zone compared with the periphery. The course of Alport's syndrome can be ameliorated by early diagnosis. Therefore, the ophthalmological examination of a patient with anterior lenticonus must be combined with a detailed medical evaluation. Ultrastructural analysis of the lens capsule can support the diagnosis of Alport's syndrome.

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

PubMed

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.

Effects of vitrification on nuclear maturation, ultrastructural changes and gene expression of canine oocytes

PubMed Central

2010-01-01

Background Cryopreservation of oocytes, which is an interesting procedure to conserve female gametes, is an essential part of reproductive biotechnology. The objective of the present study was to investigate the effects of vitrification on nuclear maturation, ultrastructural changes and gene expression of canine oocytes. Methods Immature oocytes (germinal vesicles) isolated from ovaries of normal bitches (> 6 months of age) were either vitrified in open pulled straw (OPS) using 20% ethylene glycol (EG) and 20% dimethyl sulfoxide (DMSO) as vitrification solution or exposed to vitrification solution without subjected to liquid nitrogen. After warming, oocytes were investigated for nuclear maturation following in vitro maturation (IVM), ultrastructural changes using transmission electron microscopy (TEM) and gene expression using RT-PCR. Fresh immature oocytes were used as the control group. Results The rate of resumption of meiosis in vitrified-warmed oocytes (53.4%) was significantly (P < 0.05) lower than those of control (93.8%) and exposure (91.4%) groups. However, there were no statistically significant differences among groups in the rates of GV oocytes reaching the maturation stage (metaphase II, MII). The ultrastructural alterations revealed by TEM showed that cortical granules, mitochondria, lipid droplets and smooth endoplasmic reticulum (SER) were affected by vitrification procedures. RT-PCR analysis for gene expression revealed no differences in HSP70, Dnmt1, SOD1 and BAX genes among groups, whereas Bcl2 was strongly expressed in vitrified-warmed group when compared to the control. Conclusion Immature canine oocytes were successfully cryopreserved, resumed meiosis and developed to the MII stage. The information obtained in this study is crucial for the development of an effective method to cryopreserve canine oocytes for establishment of genetic banks of endangered canid species. PMID:20565987

Expression of angiotensin II receptors in the caprine ovary and improvement of follicular viability in vitro.

PubMed

Bruno, J B; Lima-Verde, I B; Celestino, J J H; Lima, L F; Matos, M H T; Faustino, L R; Donato, M A M; Peixoto, C A; Campello, C C; Silva, J R V; Figueiredo, J R

2016-08-01

This study aimed to evaluate mRNA levels of angiotensin II (ANG II) receptors (AGTR1 and AGTR2) in caprine follicles and to investigate the influence of ANG II on the viability and in vitro growth of preantral follicles. Real-time polymerase chain reaction (PCR) was used to quantify AGTR1 and AGTR2 mRNA levels in the different follicular stages. For culture, caprine ovaries were collected, cut into 13 fragments and then either directly fixed for histological and ultrastructural analysis (fresh control) or placed in culture for 1 or 7 days in α-minumum essential medium plus (α-MEM+) with 0, 1, 5, 10, 50 or 100 ng/ml ANG II. Then, the fragments were destined to morphological, viability and ultrastructural analysis. The results showed that primordial follicles had higher levels of AGTR1 and AGTR2 mRNA than secondary follicles. Granulosa/theca cells from antral follicles had higher levels of AGTR1 mRNA than their respective cumulus-oocyte complex (COCs). After 7 days of culture, ANG II (10 or 50 ng/ml) maintained the percentages of normal follicles compared with α-MEM+. Fluorescence and ultrastructural microscopy confirmed follicular integrity in ANG II (10 ng/ml). In conclusion, a high expression of AGTR1 and AGTR2 is observed in primordial follicles. Granulosa/theca cells from antral follicles had higher levels of AGTR1 mRNA. Finally, 10 ng/ml ANG II maintained the viability of caprine preantral follicles after in vitro culture.

Ultrastructural changes and Heat Shock Proteins 70 induced by atmospheric pollution are similar to the effects observed under in vitro heavy metals stress in Conocephalum conicum (Marchantiales--Bryophyta).

PubMed

Basile, Adriana; Sorbo, Sergio; Conte, Barbara; Cardi, Manuela; Esposito, Sergio

2013-11-01

Changes in ultrastructure and induction of Heat Shock Proteins 70 have been studied in Conocephalum conicum (Marchantiales) collected in different urban and country sites in Italy. These results were compared to the effects in vitro of exposition to different heavy metals for several days. At urban sites, cellular ultrastructure was modified, and heavy metals could be observed accumulating in cell walls. Simultaneously, a strong increment in Hsp70 was detected, compared with results observed on control specimens. When C. conicum was exposed to heavy metals in vitro, comparable effects as in polluted sites were observed: Cd and Pb accumulated mostly within parenchyma and, within cells, were absorbed to cell walls or concentrated in vacuoles. Moreover, severe alterations were observed in organelles. Concomitantly, a progressive accumulation of Hsp70 was detected following heavy metals exposition. These effects are discussed in order to describe the dose and time-dependent response to heavy metal stress in C. conicum. Copyright © 2013 Elsevier Ltd. All rights reserved.

A comparative ultrastructural study of spermatozoa of the teiid lizards Cnemidophorus gularis gularis, Cnemidophorus ocellifer, and Kentropyx altamazonica (Reptilia, Squamata, Teiidae).

PubMed

Teixeira, R D; Scheltinga, D M; Trauth, S E; Colli, G R; Báo, S N

2002-06-01

The ultrastructure of the spermatozoa of Cnemidophorus gularis gularis, Cnemidophorus ocellifer, and Kentropyx altamazonica is described for the first time. Mature spermatozoa of Cnemidophorus spp. and K. altamazonica differ in the occurrence of a perforatorial base plate, the enlargement of axonemal fibers 3 and 8, and shape of mitochondria. The comparisons of the ultrastructure sperm of Cnemidophorus spp. and K. altamazonica with Ameiva ameiva [J. Morphol. (2002) in press] suggest that Ameiva and Cnemidophorus are more similar to each other than either is to Kentropyx. Statistical analyses reveal that sperm of all three species studied are significantly different in the following dimensions: head, acrosome, distal centriole length, and nuclear shoulders width. There was no variable statistically different between the Cnemidophorus spp. only. The length of the tail, midpiece, entire sperm, and nuclear rostrum are significantly different between K. altamazonica and Cnemidophorus spp. Our results indicate that sperm ultrastructure presents intra and intergeneric variability.

Acellularization-Induced Changes in Tensile Properties Are Organ Specific - An In-Vitro Mechanical and Structural Analysis of Porcine Soft Tissues

PubMed Central

Aust, Gabriela; Boldt, Andreas; Fritsch, Sebastian; Keil, Isabel; Koch, Holger; Möbius, Robert; Scheidt, Holger A.; Wagner, Martin F. X.; Hammer, Niels

2016-01-01

Introduction Though xenogeneic acellular scaffolds are frequently used for surgical reconstruction, knowledge of their mechanical properties is lacking. This study compared the mechanical, histological and ultrastructural properties of various native and acellular specimens. Materials and Methods Porcine esophagi, ureters and skin were tested mechanically in a native or acellular condition, focusing on the elastic modulus, ultimate tensile stress and maximum strain. The testing protocol for soft tissues was standardized, including the adaption of the tissue’s water content and partial plastination to minimize material slippage as well as templates for normed sample dimensions and precise cross-section measurements. The native and acellular tissues were compared at the microscopic and ultrastructural level with a focus on type I collagens. Results Increased elastic modulus and ultimate tensile stress values were quantified in acellular esophagi and ureters compared to the native condition. In contrast, these values were strongly decreased in the skin after acellularization. Acellularization-related decreases in maximum strain were found in all tissues. Type I collagens were well-preserved in these samples; however, clotting and a loss of cross-linking type I collagens was observed ultrastructurally. Elastins and fibronectins were preserved in the esophagi and ureters. A loss of the epidermal layer and decreased fibronectin content was present in the skin. Discussion Acellularization induces changes in the tensile properties of soft tissues. Some of these changes appear to be organ specific. Loss of cross-linking type I collagen may indicate increased mechanical strength due to decreasing transverse forces acting upon the scaffolds, whereas fibronectin loss may be related to decreased load-bearing capacity. Potentially, the alterations in tissue mechanics are linked to organ function and to the interplay of cells and the extracellular matrix, which is different in hollow organs when compared to skin. PMID:26960134

Aerodynamics and pollen ultrastructure in Ephedra.

PubMed

Bolinder, Kristina; Niklas, Karl J; Rydin, Catarina

2015-03-01

• Pollen dispersal is affected by the terminal settling velocity (Ut) of the grains, which is determined by their size, bulk density, and by atmospheric conditions. The likelihood that wind-dispersed pollen is captured by ovulate organs is influenced by the aerodynamic environment created around and by ovulate organs. We investigated pollen ultrastructure and Ut of Ephedra foeminea (purported to be entomophilous), and simulated the capture efficiency of its ovules. Results were compared with those from previously studied anemophilous Ephedra species.• Ut was determined using stroboscopic photography of pollen in free fall. The acceleration field around an "average" ovule was calculated, and inflight behavior of pollen grains was predicted using computer simulations. Pollen morphology and ultrastructure were investigated using SEM and STEM.• Pollen wall ultrastructure was correlated with Ut in Ephedra. The relative proportion and amount of granules in the infratectum determine pollen bulk densities, and (together with overall size) determine Ut and thus dispersal capability. Computer simulations failed to reveal any functional traits favoring anemophilous pollen capture in E. foeminea.• The fast Ut and dense ultrastructure of E. foeminea pollen are consistent with functional traits that distinguish entomophilous species from anemophilous species. In anemophilous Ephedra species, ovulate organs create an aerodynamic microenvironment that directs airborne pollen to the pollination drops. In E. foeminea, no such microenvironment is created. Ephedroid palynomorphs from the Cretaceous share the ultrastructural characteristics of E. foeminea, and at least some may, therefore, have been produced by insect-pollinated plants. © 2015 Botanical Society of America, Inc.

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

PubMed

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 < .01) in Bm thickness with significant decrease in Leydig cell nuclear diameter (p < .05) and volume (p < .01) when compared with control 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 < .01) in testosterone levels. There was no significant effect on malondialdehyde and glutathione levels. Virgin coconut oil improved testicular morphology and reversed HAART-induced ultrastructural alterations. Further studies on putative mechanism are required. © 2017 Blackwell Verlag GmbH.

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

PubMed Central

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

2016-01-01

Study Objective: 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. Methods: 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). Results: 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. Conclusions: 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. Citation: de Vivo L, Nelson AB, Bellesi M, Noguti J, Tononi G, Cirelli C. Loss of sleep affects the ultrastructure of pyramidal neurons in the adolescent mouse frontal cortex. SLEEP 2016;39(4):861–874. PMID:26715225

Ultrastructural demonstration of chemical modification of melanogenesis in hairless mouse skin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nishimura, M.; Gellin, G.A.; Hoshino, S.

1982-02-01

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 anmore » 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.« less

Gromochytrium mamkaevae gen. & sp. nov. and two new orders: Gromochytriales and Mesochytriales (Chytridiomycetes).

PubMed

Karpov, S A; Kobseva, A A; Mamkaeva, M A; Mamkaeva, K A; Mikhailov, K V; Mirzaeva, G S; Aleoshin, V V

2014-06-01

During the last decade several new orders were established in the class Chytridiomycetes on the basis of zoospore ultrastructure and molecular phylogeny. Here we present the ultrastructure and molecular phylogeny of strain x-51 CALU - a parasite of the alga Tribonema gayanum, originally described as Rhizophydium sp. based on light microscopy. Detailed investigation revealed that the zoospore ultrastructure of this strain has unique characters not found in any order of Chytridiomycetes: posterior ribosomal core unbounded by the endoplasmic reticulum and detached from the nucleus or microbody-lipid complex, and kinetosome composed of microtubular doublets. An isolated phylogenetic position of x-51 is further confirmed by the analysis of 18S and 28S rRNA sequences, and motivates the description of a new genus and species Gromochytrium mamkaevae. The sister position of G. mamkaevae branch relative to Mesochytrium and a cluster of environmental sequences, as well as the ultrastructural differences between Gromochytrium and Mesochytrium zoospores prompted us to establish two new orders: Gromochytriales and Mesochytriales.

Physiological, cellular and molecular aspects of the desiccation tolerance in Anadenanthera colubrina seeds during germination.

PubMed

Castro, L E; Guimarães, C C; Faria, J M R

2017-11-01

During germination, orthodox seeds become gradually intolerant to desiccation, and for this reason, they are a good model for recalcitrance studies. In the present work, physiological, biochemical, and ultrastructural aspects of the desiccation tolerance were characterized during the germination process of Anadenanthera colubrina seeds. The seeds were imbibed during zero (control), 2, 8, 12 (no germinated seeds), and 18 hours (germinated seeds with 1 mm protruded radicle); then they were dried for 72 hours, rehydrated and evaluated for survivorship. Along the imbibition, cytometric and ultrastructural analysis were performed, besides the extraction of the heat-stable proteins. Posteriorly to imbibition and drying, the evaluation of ultrastructural damages was performed. Desiccation tolerance was fully lost after root protrusion. There was no increase in 4C DNA content after the loss of desiccation tolerance. Ultrastructural characteristics of cells from 1mm roots resembled those found in the recalcitrant seeds, in both hydrated and dehydrated states. The loss of desiccation tolerance coincided with the reduction of heat-stable proteins.

Marine bivalve geochemistry and shell ultrastructure from modern low pH environments

NASA Astrophysics Data System (ADS)

Hahn, S.; Rodolfo-Metalpa, R.; Griesshaber, E.; Schmahl, W. W.; Buhl, D.; Hall-Spencer, J. M.; Baggini, C.; Fehr, K. T.; Immenhauser, A.

2011-10-01

Bivalve shells can provide excellent archives of past environmental change but have not been used to interpret ocean acidification events. We investigated carbon, oxygen and trace element records from different shell layers in the mussels Mytilus galloprovincialis (from the Mediterranean) and M. edulis (from the Wadden Sea) combined with detailed investigations of the shell ultrastructure. Mussels from the harbour of Ischia (Mediterranean, Italy) were transplanted and grown in water with mean pHT 7.3 and mean pHT 8.1 near CO2 vents on the east coast of the island of Ischia. The shells of transplanted mussels were compared with M. edulis collected at pH ~8.2 from Sylt (German Wadden Sea). Most prominently, the shells recorded the shock of transplantation, both in their shell ultrastructure, textural and geochemical record. Shell calcite, precipitated subsequently under acidified seawater responded to the pH gradient by an in part disturbed ultrastructure. Geochemical data from all test sites show a strong metabolic effect that exceeds the influence of the low-pH environment. These field experiments showed that care is needed when interpreting potential ocean acidification signals because various parameters affect shell chemistry and ultrastructure. Besides metabolic processes, seawater pH, factors such as salinity, water temperature, food availability and population density all affect the biogenic carbonate shell archive.

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

PubMed

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 steroid hormones on nuclear membrane and membrane-bound heterochromatin from breast cancer cells evaluated by fractal morphometry.

PubMed

Losa, G A; Graber, R; Baumann, G; Nonnenmacher, T F

1999-10-01

To evaluate the effect of steroid hormones on the ultrastructure of nuclear heterochromatin and perinuclear membranes in human MCF-7 breast cancer cells. MCF-7 cells were cultured briefly (five minutes) in the presence of 10(-9) M estrogen 17 beta-estradiol, a stimulator of cell proliferation and/or 10(-9) M glucocorticoid dexamethasone. Changes in the morphologic complexity of nuclear membrane-bound heterochromatin (NMBHC) and nuclear membranes (ENM) were assessed by means of the fractal capacity dimension, D, a noneuclidean geometric descriptor of complex, irregular bodies. 17 beta-estradiol (10(-9) M) enhanced the ultrastructural irregularity of NMBHC, as documented by the increased value of D, whereas dexamethasone (10(-9) M) reduced it when compared to NMBHC from untreated MCF-7 control cells. In contrast, neither steroid modified ENM ultrastructure. Changes in the nuclear heterochromatin complexity induced by estrogen 17 beta-estradiol occurred concomitantly with functional changes at the cell periphery, such as activation of the phospholipase C, a cell membrane-associated enzyme involved in signal transduction. Dexamethasone reduced the ultrastructural complexity of NMBHC without affecting functional processes. Fractal morphometry proved its usefulness in quantifying early ultrastructural changes in nuclear components induced in MCF-7 cells by steroid hormones, 17 beta-estradiol and dexamethasone.

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

PubMed

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.

Bisphenol A-induced ultrastructural changes in the testes of common marmoset

PubMed Central

Vijaykumar, Tushara; Singh, Dipty; Vanage, Geeta R.; Dhumal, Rohit V.; Dighe, Vikas D.

2017-01-01

Background & objectives: Bisphenol A (BPA) is an endocrine disruptor that is widely used in the manufacture of polycarbonate plastics, epoxy resins and dental sealants. It is known to have adverse effects on spermatogenesis in rodents. This study was aimed to evaluate the effects of BPA in adult common marmoset owing to its similarities with human spermatogenesis. Methods: Sixteen marmosets were divided into four groups (n=4 per group) and given oral doses of BPA (2.5, 12.5 and 25 μg/kg BW/day) for 70 days to cover two spermatogenic cycles, and the control group received only vehicle (honey). Testes were processed for histological and transmission electron microscopy studies. Results: Histology of the testis showed sloughing of germ cells into the lumen, increase in interstitial space and vacuolation of Sertoli cell cytoplasm. Ultrastructural analysis of the testis revealed several degenerative effects on the basement membrane, Sertoli cells, Leydig cells and other developing germ cells in the 12.5 and 25 μg/kg BW/day groups as compared to control. Interpretation & conclusions: The observed ultrastructural changes caused by BPA in testicular morphology might be indicative of a perturbed sperm production. Considering the genetic and spermatogenic similarities of common marmoset (Callithrix jacchus) and humans, the study findings are of significance. Further studies are, however, needed to elucidate the mechanism of action. PMID:29168469

Meibomian gland studies: histologic and ultrastructural investigations.

PubMed

Jester, J V; Nicolaides, N; Smith, R E

1981-04-01

Heightened interest in meibomian gland dysfunction has prompted us to evaluate the normal morphological and ultrastructural characteristics of the meibomian gland. Histologic analysis of human, primate, steer, and rabbit glands revealed evidence of keratinized epithelium extending throughout the meibomian gland duct. Characteristic ultrastructural features of keratinized epithelium identified in primate and rabbit glands included tonofilaments, keratohyaline granules, lamellar bodies, and keratinized squamous cells. Comparison of the meibomian gland duct to the pilosebaceous canal and the sebaceous duct brought out certain dissimilarities such as (1) the lack of a well-developed stratum granulosum and (2) the absence of lipid inclusions within transitional cells from duct to acini. We postulate that abnormalities of the keratinizing process may be responsible for meibomian gland dysfunction states.

Infrasound-induced hemodynamics, ultrastructure, and molecular changes in the rat myocardium.

PubMed

Pei, Zhaohui; Sang, Hanfei; Li, Ruiman; Xiao, Pingxi; He, Jiangui; Zhuang, Zhiqiang; Zhu, Miaozhang; Chen, Jingzao; Ma, Hong

2007-04-01

Recent interest in adverse effects of infrasound on organisms arises from health concerns. We assessed the association between infrasound exposure of 5 Hz at 130 dB and changes of cardiac ultrastructure and function in rats. Thirty-two Sprague-Dawley rats were randomized into control, 1, 7, and 14 days groups for 2 h of infrasound once daily according to planned schedules. Changes of cardiac ultrastructure, hemodynamics indices, intracellular Ca(2+) concentrations ([Ca(2+)](i)), and sarcoplasmic reticulum Ca(2+)-ATPase 2 (SERCA2) were detected. Heart rates in 1 day group were significantly increased compared with control group and no significant changes in other groups. Left ventricular systolic pressures were significantly increased with time. Left ventricular diastolic end pressure and maximum rising rates of left ventricular pressure (+dl/dt) were significantly increased in 7 and 14 days groups and not changed in 1 day group, compared with control group. Maximum dropping rates of left ventricular pressure (-dl/dt) were significantly decreased in 7 and 14 days groups and not changed in 1 day group, compared with control group. In heart cells, there were several swelled mitochondria in 1 day group, more swelled mitochondria in 7 days group, platelet aggregation in the intercellular substance in 14 days group. [Ca(2+)](i) were significantly increased with time. There was a significant increase in SERCA2 in 1 day group, while a significant decrease in 7 and 14 days groups, compared with control group. Infrasound of 5 Hz at 130 dB can damage cardiac ultrastructure and function. Changes of [Ca(2+)](i) and SERCA2 play an important role in the secondary cardiac damage. (c) 2007 Wiley Periodicals, Inc.

Ultrastructure of Plant Leaf Cuticles in relation to Sample Preparation as Observed by Transmission Electron Microscopy

PubMed Central

Guzmán, Paula; Fernández, Victoria; García, María Luisa; Fernández, Agustín; Gil, Luis

2014-01-01

The leaf cuticular ultrastructure of some plant species has been examined by transmission electron microscopy (TEM) in only few studies. Attending to the different cuticle layers and inner structure, plant cuticles have been grouped into six general morphological types. With the aim of critically examining the effect of cuticle isolation and preparation for TEM analysis on cuticular ultrastructure, adaxial leaf cuticles of blue-gum eucalypt, grey poplar, and European pear were assessed, following a membrane science approach. The embedding and staining protocols affected the ultrastructure of the cuticles analysed. The solubility parameter, surface tension, and contact angles with water of pure Spurr's and LR-White resins were within a similar range. Differences were however estimated for resin : solvent mixtures, since Spurr's resin is combined with acetone and LR-White resin is mixed with ethanol. Given the composite hydrophilic and lipophilic nature of plant cuticles, the particular TEM tissue embedding and staining procedures employed may affect sample ultrastructure and the interpretation of the results in physicochemical and biological terms. It is concluded that tissue preparation procedures may be optimised to facilitate the observation of the micro- and nanostructure of cuticular layers and components with different degrees of polarity and hydrophobicity. PMID:24895682

Haemoproteus in barn and collared scops owls from Thailand

PubMed Central

Pornpanom, Pornchai; Lertwatcharasarakul, Preeda; Kasorndorkbua, Chaiyan; Salakij, Jarernsak

2018-01-01

The barn owl (BO) and the collared scops owl (CSO) are common nocturnal raptors throughout Thailand. Blood samples from 23 adult BOs and 14 CSOs were collected and processed for complete blood cell counts and parasite morphological examinations. Two Haemoproteus-positive samples were processed for ultrastructural observation. Polymerase chain reaction (PCR) analysis for a partial cytochrome b gene (cytb) from Haemoproteus was performed in all samples. Haemoproteus presence detected by light microscopy was lower than that detected by PCR (30.4% and 34.8%, respectively, in BO; and 50.0% and 78.6%, respectively, in CSO). Comparative hematology revealed that Haemoproteus-positive BOs had higher mean cell hemoglobin concentration, total leukocyte, absolute heterophil, basophil, and monocyte counts than Haemoproteus-negative BOs, but no significant differences between Haemoproteus-negative and -positive CSOs. Monocyte ultrastructure analysis revealed a role in the elimination of gametocytes. Morphologically, the Haemoproteus in 3 BOs and 6 CSOs were identified as H. noctuae, while that in 1 CSO was identified as H. syrnii. Phylogenetic analysis indicated the Haemoproteus spp. in 8 BOs and 7 CSOs were not closely related to H. noctuae or H. syrnii, and the cytb of 2 CSOs was that of H. syrnii. These results should be useful for study of Haemoproteus. PMID:29032656

The effect of sibutramine on platelet morphology of Spraque-Dawley rats fed a high energy diet.

PubMed

Oberholzer, Hester Magdalena; Van Der Schoor, Ciska; Pretorius, Etheresia

2013-06-01

The aim of this study was to investigate the effect of Sibutramine on platelet ultrastructure and discuss the morphological observations in relation to known physiological effects of the compound. Six-week-old, female Spraque-Dawley rats were used in this study. The animals were placed on a high energy diet after which sibutramine administration followed. Blood was drawn on the day of termination and platelet rich plasma was obtained to prepare plasma smears for analysis. Scanning electron microscopy was used to investigate the ultrastructure of the platelets. Platelets of the Sibutramine-treated animals showed smooth surface with limited pseudopodia formation when compared with that of the control animals. Higher magnification of the platelet surface showed membrane tears and swelling, typically seen in necrotic cells. It can therefore be concluded from these results that Sibutramine alters the membrane morphology of platelets to that typical of necrotic cells. Copyright © 2013 Wiley Periodicals, Inc.

Morphological and biochemical examination of Cosmos 1887 rat heart tissue. Part 1: Ultrastructure

NASA Technical Reports Server (NTRS)

Philpott, D. E.; Popova, I. A.; Kato, K.; Stevenson, J.; Miquel, J.; Sapp, W.

1990-01-01

Morphological changes were observed in the left ventricle of rat heart tissue from animals flown on the Cosmos 1887 biosatellite for 12.5 days. These tissues were compared to the synchronous and vivarium control hearts. While many normal myofibrils were observed, others exhibited ultrastructural alterations, i.e., damaged and irregular-shaped mitochondria and generalized myofibrillar edema. Analysis of variance (ANOVA) of the volume density data revealed a statistically significant increase in glycogen and a significant decrease in mitochondria compared to the synchronous and vivarium controls. Point counting indicated an increase in lipid and myeloid bodies and a decrease in microtubules, but these changes were not statistically significant. In addition, the flight animals exhibited some patchy loss of protofibrils (actin and myosin filaments) and some abnormal supercontracted myofibrils that were not seen in the controls. This study was undertaken to gain insight into the mechanistic aspects of cardiac changes in both animals and human beings as a consequence of space travel. Cardiac hypotrophy and fluid shifts have been observed after actual or simulated weightlessness and raise concerns about the functioning of the heart and circulatory system during and after travel in space.

Immunotactoid Glomerulopathy and Cryoglobulinemic Nephropathy: Two Entities with Many Similarities. A Unified Conceptual Approach.

PubMed

Herrera, Guillermo A; Ojemakinde, Kunle O; Turbat-Herrera, Elba A; Gu, Xin; Zeng, Xu; Iskandar, Samy S

2015-01-01

Immunotactoid glomerulopathy is a rare disorder that has been characterized at the ultrastructural level. Due to its rarity, there are few comprehensive studies relating to this disorder. Electron microscopy essentially characterizes this disease. The glomerular electron dense deposits which are typical of this condition consist of aggregates of highly organized microtubular structures of various diameters, but generally measuring 30-50 nm in width with a propensity to dispose themselves in parallel bundles intersecting in different planes. This study compares a large series of patients with cryoglobulinemic nephropathy with a series of patients with immunotactoid glomerulopathy to address whether there may be similarities that warrant considering these two entities part of a spectrum. This study reviews the clinicopathologic features of both entities and emphasizes ultrastructural findings that characterize them. Significant immunomorphologic overlap was found when these two disorders were compared in this study. There were also striking similarities in clinical presentation/behavior, laboratory findings and prognosis. Proteomic analysis has also demonstrated similar spectra for both entities. We postulate that immunotactoid glomerulopathy and cryoglobulinemic nephropathy are part of the spectrum of renal manifestations in patients with circulating cryoglobulins and renal disease.

In vitro effects of ascorbic acid and β-glycerophosphate on human gingival fibroblast cells.

PubMed

Martinez, Elizabeth F; Donato, Tatiani A G; Arana-Chavez, Victor E

2012-10-01

Ascorbic acid (AA) and β-glycerophosphate (βG) are considered in vitro osteogenic factors important to the differentiation of osteoblastic progenitor and dental pulp cells into mineralized tissue-forming cells. So, the present study investigated in vitro if these mineralizing inducible factors (AA and βG) could influence differentiation of human gingival fibroblasts when compared with human pulp cells and osteogenic cells derived from rat calvaria cultured. The expression of osteopontin (OPN) and osteoadherin (OSAD) was analyzed by indirect immunofluorescence, immunocytochemistry as well as Western-blotting. In addition, the main ultrastructural aspects were also investigated. No mineralized matrix formation occurred on gingival fibroblasts induced with AA+βG. On these cells, no expression of OPN and OSAD was observed when compared with pulp cells, pulp cells induced with AA+βG as well as osteogenic cells. Ultrastructure analysis additionally showed that gingival fibroblasts exhibited typical fibroblast morphology with no nodule formation. The present findings showed that AA and βG could not promote a mineralized cell differentiation of human gingival fibroblasts and confirm that human dental pulp cells, as the osteogenic cells, are capable to form a mineralized extracellular. Copyright © 2012 Elsevier Ltd. All rights reserved.

The influence of microgravity and spaceflight on columella cell ultrastructure in starch-deficient mutants of Arabidopsis

NASA Technical Reports Server (NTRS)

Guisinger, M. M.; Kiss, J. Z.

1999-01-01

The ultrastructure of root cap columella cells was studied by morphometric analysis in wild-type, a reduced-starch mutant, and a starchless mutant of Arabidopsis grown in microgravity (F-microgravity) and compared to ground 1g (G-1g) and flight 1g (F-1g) controls. Seedlings of the wild-type and reduced-starch mutant that developed during an experiment on the Space Shuttle (both the F-microgravity samples and the F-lg control) exhibited a decreased starch content in comparison to the G-1g control. These results suggest that some factor associated with spaceflight (and not microgravity per se) affects starch metabolism. Elevated levels of ethylene were found during the experiments on the Space Shuttle, and analysis of ground controls with added ethylene demonstrated that this gas was responsible for decreased starch levels in the columella cells. This is the first study to use an on-board centrifuge as a control when quantifying starch in spaceflight-grown plants. Furthermore, our results show that ethylene levels must be carefully considered and controlled when designing experiments with plants for the International Space Station.

Comparing different preparation methods to study human fibrin fibers and platelets using TEM.

PubMed

Buys, Antoinette V; Pretorius, Etheresia

2012-06-01

For the study of cellular ultrastructure, the sample needs to be stabilized by fixation, with the ultimate aim to preserve the native tissue organization and to protect the tissue against later stages of preparation. Chemical and freezing fixation are most used, and chemical fixation employs agents that permeate tissues and cells by diffusion and covalently bind with their major biochemical constituents to fix them. Most widely used chemical fixatives are aldehydes, e.g., formaldehyde and glutaraldehyde, which are noncoagulating, crosslinking agents. Cryofixation methods for ultrastructural studies are also popular, and high-pressure freezing immobilizes all cell constituents and arrests biological activity by removing the thermal energy from the system. In the current research, we used platelet-rich plasma (PRP) to study expansive fibrin fibers and platelet ultrastructure to compare the two fixation techniques. We also used thrombin and calcium chloride as a clotting agent to determine the technique most suitable for the formation of extensive fibrin networks. Chemically fixated fibrin fibers were more compact and condensed and also showed a banding pattern on longitudinal sections. High-pressure frozen samples were more dispersed while platelets fixated showed better preserved cellular membranes and organelle structure. PRP coagulated by addition of CaCl(2) showed blood platelets that are noticeably more activated compared with PRP; however, with thrombin, a sharp ultrastructure was seen. We conclude that PRP mixed with thrombin, and freeze substituted, is the most suitable method for the study of extensive fibrin fibers as well as platelets. Copyright © 2011 Wiley Periodicals, Inc.

The cytochemical and ultrastructural characteristics of phagocytes in the Pacific oyster Crassostrea gigas.

PubMed

Jiang, Shuai; Jia, Zhihao; Xin, Lusheng; Sun, Ying; Zhang, Ran; Wang, Weilin; Wang, Lingling; Song, Linsheng

2016-08-01

Phagocytes have been proved to play vital roles in the innate immune response. However, the cellular characteristics of phagocytes in invertebrates, especially in molluscs, remain largely unknown. In the present study, fluorescence activated cell sorting (FACS) was employed to sort the phagocytes from the non-phagocytic haemocytes of the Pacific oyster Crassostrea gigas. The cytochemical staining analysis revealed that phagocytes were positive staining for α-naphthyl acetate esterase and myeloperoxidase, while negative staining for toluidine blue and periodic acid-Schiff. The non-phagocytic haemocytes exhibited positive staining for periodic acid-Schiff, weak positive staining for toluidine blue, but negative staining for α-naphthyl acetate esterase and myeloperoxidase. In addition, phagocytes exhibited ultrastructural cellular features similar to those of macrophages, with large cell diameter, rough cell membrane and extended pseudopodia revealed by the scanning electron microscopy, while the non-phagocytic haemocytes exhibited small cell diameter, smooth cell surface and round spherical shape. Transmission electron microscopy further demonstrated that phagocytes were abundant of cytoplasmic bodies and mitochondria, while non-phagocytic haemocytes were characterized as the comparatively large cell nucleus with contorted and condensed heterochromatin adherent to the nuclear envelope. Moreover, compared with non-phagocytic haemocytes, phagocytes exhibited significantly higher levels of intracellular cytokines, including tumor necrosis factor, interferon-like protein and interleukin-17, and significantly higher abundance of lysosome and reactive oxygen species, which were of great importance to the activation of immune response and pathogen clearance. Taken together, these findings revealed the different cytochemical and ultrastructural features between phagocytes and non-phagocytic haemocytes in C. gigas, which would provide an important clue to investigate the mechanism of phagocytosis underlying the innate immune response. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

PubMed

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.

Scanning EM of non-heavy metal stained biosamples: Large-field of view, high contrast and highly efficient immunolabeling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuipers, Jeroen; Boer, Pascal de; Giepmans, Ben N.G., E-mail: b.n.g.giepmans@umcg.nl

Scanning electron microscopy (SEM) is increasing its application in life sciences for electron density measurements of ultrathin sections. These are traditionally analyzed with transmission electron microscopy (TEM); by most labs, SEM analysis still is associated with surface imaging only. Here we report several advantages of SEM for thin sections over TEM, both for structural inspection, as well as analyzing immuno-targeted labels such as quantum dots (QDs) and gold, where we find that QD-labeling is ten times more efficient than gold-labeling. Furthermore, we find that omitting post-staining with uranyl and lead leads to QDs readily detectable over the ultrastructure, but undermore » these conditions ultrastructural contrast was even almost invisible in TEM examination. Importantly, imaging in SEM with STEM detection leads to both outstanding QDs and ultrastructural contrast. STEM imaging is superior over back-scattered electron imaging of these non-contrasted samples, whereas secondary electron detection cannot be used at all. We conclude that examination of ultrathin sections by SEM, which may be immunolabeled with QDs, will allow rapid and straightforward analysis of large fields with more efficient labeling than can be achieved with immunogold. The large fields of view routinely achieved with SEM, but not with TEM, allows straightforward raw data sharing using virtual microscopy, also known as nanotomy when this concerns EM data in the life sciences. - Highlights: • High resolution and large fields of view via nanotomy or virtual microscopy. • Highly relevant for EM‐datasets where information density is high. • Sample preparation with low contrast good for STEM, not TEM. • Quantum dots now stand out in STEM‐based detection. • 10 Times more efficient labeling with quantum dots compared to gold.« less

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

NASA Astrophysics Data System (ADS)

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.

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

PubMed

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.

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

PubMed

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.

Cell Wall Ultrastructure of Stem Wood, Roots, and Needles of a Conifer Varies in Response to Moisture Availability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pattathil, Sivakumar; Ingwers, Miles W.; Victoriano, Olivia L.

The composition, integrity, and architecture of the macromolecular matrix of cell walls, collectively referred to as cell wall ultrastructure, exhibits variation across species and organs and among cell types within organs. Indirect approaches have suggested that modifications to cell wall ultrastructure occur in response to abiotic stress; however, modifications have not been directly observed. Glycome profiling was used to study cell wall ultrastructure by examining variation in composition and extractability of non-cellulosic glycans in cell walls of stem wood, roots, and needles of loblolly pine saplings exposed to high and low soil moisture. Soil moisture influenced physiological processes and themore » overall composition and extractability of cell wall components differed as a function of soil moisture treatments. The strongest response of cell wall ultrastructure to soil moisture was increased extractability of pectic backbone epitopes in the low soil moisture treatment. The higher abundance of these pectic backbone epitopes in the oxalate extract indicate that the loosening of cell wall pectic components could be associated with the release of pectic signals as a stress response. The increased extractability of pectic backbone epitopes in response to low soil moisture availability was more pronounced in stem wood than in roots or needles. Additional responses to low soil moisture availability were observed in lignin associated carbohydrates released in chlorite extracts of stem wood, including an increased abundance of pectic arabinogalactan epitopes. Overall, these results indicate that cell walls of loblolly pine organs undergo changes in their ultrastructural composition and extractability as a response to soil moisture availability and that cell walls of the stem wood are more responsive to low soil moisture availability compared to cell walls of roots and needles. In conclusion, to our knowledge, this is the first direct evidence, delineated by glycomic analyses, that abiotic stress affects cell wall ultrastructure. This study is also unique in that glycome profiling of pine needles has never before been reported.« less

Cell Wall Ultrastructure of Stem Wood, Roots, and Needles of a Conifer Varies in Response to Moisture Availability.

PubMed

Pattathil, Sivakumar; Ingwers, Miles W; Victoriano, Olivia L; Kandemkavil, Sindhu; McGuire, Mary Anne; Teskey, Robert O; Aubrey, Doug P

2016-01-01

The composition, integrity, and architecture of the macromolecular matrix of cell walls, collectively referred to as cell wall ultrastructure, exhibits variation across species and organs and among cell types within organs. Indirect approaches have suggested that modifications to cell wall ultrastructure occur in response to abiotic stress; however, modifications have not been directly observed. Glycome profiling was used to study cell wall ultrastructure by examining variation in composition and extractability of non-cellulosic glycans in cell walls of stem wood, roots, and needles of loblolly pine saplings exposed to high and low soil moisture. Soil moisture influenced physiological processes and the overall composition and extractability of cell wall components differed as a function of soil moisture treatments. The strongest response of cell wall ultrastructure to soil moisture was increased extractability of pectic backbone epitopes in the low soil moisture treatment. The higher abundance of these pectic backbone epitopes in the oxalate extract indicate that the loosening of cell wall pectic components could be associated with the release of pectic signals as a stress response. The increased extractability of pectic backbone epitopes in response to low soil moisture availability was more pronounced in stem wood than in roots or needles. Additional responses to low soil moisture availability were observed in lignin-associated carbohydrates released in chlorite extracts of stem wood, including an increased abundance of pectic arabinogalactan epitopes. Overall, these results indicate that cell walls of loblolly pine organs undergo changes in their ultrastructural composition and extractability as a response to soil moisture availability and that cell walls of the stem wood are more responsive to low soil moisture availability compared to cell walls of roots and needles. To our knowledge, this is the first direct evidence, delineated by glycomic analyses, that abiotic stress affects cell wall ultrastructure. This study is also unique in that glycome profiling of pine needles has never before been reported.

Cell Wall Ultrastructure of Stem Wood, Roots, and Needles of a Conifer Varies in Response to Moisture Availability

DOE PAGES

Pattathil, Sivakumar; Ingwers, Miles W.; Victoriano, Olivia L.; ...

2016-06-24

The composition, integrity, and architecture of the macromolecular matrix of cell walls, collectively referred to as cell wall ultrastructure, exhibits variation across species and organs and among cell types within organs. Indirect approaches have suggested that modifications to cell wall ultrastructure occur in response to abiotic stress; however, modifications have not been directly observed. Glycome profiling was used to study cell wall ultrastructure by examining variation in composition and extractability of non-cellulosic glycans in cell walls of stem wood, roots, and needles of loblolly pine saplings exposed to high and low soil moisture. Soil moisture influenced physiological processes and themore » overall composition and extractability of cell wall components differed as a function of soil moisture treatments. The strongest response of cell wall ultrastructure to soil moisture was increased extractability of pectic backbone epitopes in the low soil moisture treatment. The higher abundance of these pectic backbone epitopes in the oxalate extract indicate that the loosening of cell wall pectic components could be associated with the release of pectic signals as a stress response. The increased extractability of pectic backbone epitopes in response to low soil moisture availability was more pronounced in stem wood than in roots or needles. Additional responses to low soil moisture availability were observed in lignin associated carbohydrates released in chlorite extracts of stem wood, including an increased abundance of pectic arabinogalactan epitopes. Overall, these results indicate that cell walls of loblolly pine organs undergo changes in their ultrastructural composition and extractability as a response to soil moisture availability and that cell walls of the stem wood are more responsive to low soil moisture availability compared to cell walls of roots and needles. In conclusion, to our knowledge, this is the first direct evidence, delineated by glycomic analyses, that abiotic stress affects cell wall ultrastructure. This study is also unique in that glycome profiling of pine needles has never before been reported.« less

First investigation of the collagen D-band ultrastructure in fossilized vertebrate integument.

PubMed

Lingham-Soliar, Theagarten; Wesley-Smith, James

2008-10-07

The ultrastructure of dermal fibres of a 200Myr thunniform ichthyosaur, Ichthyosaurus, specifically the 67nm axial repeat D-banding of the fibrils, which characterizes collagen, is presented for the first time by means of scanning electron microscopy (SEM) analysis. The fragment of material investigated is part of previously described fossilized skin comprising an architecture of layers of oppositely oriented fibre bundles. The wider implication, as indicated by the extraordinary quality of preservation, is the robustness of the collagen molecule at the ultrastructural level, which presumably contributed to its survival during the initial processes of decomposition prior to mineralization. Investigation of the elemental composition of the sample by SEM-energy dispersive X-ray spectroscopy indicates that calcite and phosphate played important roles in the rapid mineralization and fine replication of the collagen fibres and fibrils. The exceedingly small sample used in the investigation and high level of information achieved indicate the potential for minimal damage to prized museum specimens; for example, ultrastructural investigations by SEM may be used to help resolve highly contentious questions, for example, 'protofeathers' in the Chinese dinosaurs.

First investigation of the collagen D-band ultrastructure in fossilized vertebrate integument

PubMed Central

Lingham-Soliar, Theagarten; Wesley-Smith, James

2008-01-01

The ultrastructure of dermal fibres of a 200 Myr thunniform ichthyosaur, Ichthyosaurus, specifically the 67 nm axial repeat D-banding of the fibrils, which characterizes collagen, is presented for the first time by means of scanning electron microscopy (SEM) analysis. The fragment of material investigated is part of previously described fossilized skin comprising an architecture of layers of oppositely oriented fibre bundles. The wider implication, as indicated by the extraordinary quality of preservation, is the robustness of the collagen molecule at the ultrastructural level, which presumably contributed to its survival during the initial processes of decomposition prior to mineralization. Investigation of the elemental composition of the sample by SEM–energy dispersive X-ray spectroscopy indicates that calcite and phosphate played important roles in the rapid mineralization and fine replication of the collagen fibres and fibrils. The exceedingly small sample used in the investigation and high level of information achieved indicate the potential for minimal damage to prized museum specimens; for example, ultrastructural investigations by SEM may be used to help resolve highly contentious questions, for example, ‘protofeathers’ in the Chinese dinosaurs. PMID:18577504

δ- and γ-tocotrienols induce classical ultrastructural apoptotic changes in human T lymphoblastic leukemic cells.

PubMed

Wong, Rebecca S Y; Radhakrishnan, Ammu K; Ibrahim, Tengku Azmi Tengku; Cheong, Soon-Keng

2012-06-01

Tocotrienols are isomers of the vitamin E family, which have been reported to exert cytotoxic effects in various cancer cells. Although there have been some reports on the effects of tocotrienols in leukemic cells, ultrastructural evidence of tocotrienol-induced apoptotic cell death in leukemic cells is lacking. The present study investigated the effects of three isomers of tocotrienols (alpha, delta, and gamma) on a human T lymphoblastic leukemic cell line (CEM-SS). Cell viability assays showed that all three isomers had cytotoxic effects (p < 0.05) on CEM-SS cells with delta-tocotrienol being the most potent. Transmission electron microscopy showed that the cytotoxic effects by delta- and gamma-tocotrienols were through the induction of an apoptotic pathway as demonstrated by the classical ultrastructural apoptotic changes characterized by peripheral nuclear chromatin condensation and nuclear fragmentation. These findings were confirmed biochemically by the demonstration of phosphatidylserine externalization via flow cytometry analysis. This is the first study showing classical ultrastructural apoptotic changes induced by delta- and gamma-tocotrienols in human T lymphoblastic leukemic cells.

Histologic and ultrastructural evaluation of fresh and frozen-thawed human ovarian xenografts in nude mice.

PubMed

Nisolle, M; Casanas-Roux, F; Qu, J; Motta, P; Donnez, J

2000-07-01

To compare histologic and ultrastructural characteristics of fresh and frozen-thawed human ovarian cortical tissue grafted into nude mice. Experimental prospective study. An academic research environment. Ovarian biopsy specimens were obtained from 13 women undergoing laparoscopy for tubal ligation or infertility. Forty nude mice. A minilaparotomy was performed to place fresh and frozen-thawed ovarian grafts subcutaneously (sc) or intraperitoneally (ip). Removal of the ovarian grafts was performed at 24 days. [1] the follicular population, [2] fibrosis, [3] vascularization of the grafted tissue, and [4] ultrastructural evaluation. A greater fibrosis relative surface area was noted in frozen-thawed transplanted tissue than in fresh transplants. Regardless of this fibrosis, a similar follicular density was observed in fresh and frozen-thawed ovarian tissue 24 days after transplantation. Active angiogenesis was proved by both immunohistochemical study of the vascular endothelial growth factor and morphometric study of the vascular network. Normal ultrastructural characteristics were noted in frozen-thawed ovarian biopsies. Angiogenesis allows implantation of the graft even if it has been cryopreserved and thawed similarly to implantation of fresh tissue. The greater fibrosis observed in grafts after cryopreservation and implantation does not seem to affect the primordial and primary ovocyte population and their ultrastructural characteristics, but further studies must be conducted to prove that after cryopreservation and transplantation, ovocytes may achieve full maturation and fertilization.

Mitochondrial and Morphologic Alterations in Native Human Corneal Endothelial Cells Associated With Diabetes Mellitus.

PubMed

Aldrich, Benjamin T; Schlötzer-Schrehardt, Ursula; Skeie, Jessica M; Burckart, Kimberlee A; Schmidt, Gregory A; Reed, Cynthia R; Zimmerman, M Bridget; Kruse, Friedrich E; Greiner, Mark A

2017-04-01

To characterize changes in the energy-producing metabolic activity and morphologic ultrastructure of corneal endothelial cells associated with diabetes mellitus. Transplant suitable corneoscleral tissue was obtained from donors aged 50 to 75 years. We assayed 3-mm punches of endothelium-Descemet membrane for mitochondrial respiration and glycolysis activity using extracellular flux analysis of oxygen and pH, respectively. Transmission electron microscopy was used to assess qualitative and quantitative ultrastructural changes in corneal endothelial cells and associated Descemet membrane. For purposes of analysis, samples were divided into four groups based on a medical history of diabetes regardless of type: (1) nondiabetic, (2) noninsulin-dependent diabetic, (3) insulin-dependent diabetic, and (4) insulin-dependent diabetic with specified complications due to diabetes (advanced diabetic). In total, 229 corneas from 159 donors were analyzed. Insulin-dependent diabetic samples with complications due to diabetes displayed the lowest spare respiratory values compared to all other groups (P ≤ 0.002). The remaining mitochondrial respiration and glycolysis metrics did not differ significantly among groups. Compared to nondiabetic controls, the endothelium from advanced diabetic samples had alterations in mitochondrial morphology, pronounced Golgi bodies associated with abundant vesicles, accumulation of lysosomal bodies/autophagosomes, and focal production of abnormal long-spacing collagen. Extracellular flux analysis suggests that corneal endothelial cells of donors with advanced diabetes have impaired mitochondrial function. Metabolic findings are supported by observed differences in mitochondrial morphology of advanced diabetic samples but not controls. Additional studies are needed to determine the precise mechanism(s) by which mitochondria become impaired in diabetic corneal endothelial cells.

Different effects of amino acid-based and glucose-based dialysate from peritoneal dialysis patients on mesothelial cell ultrastructure and function.

PubMed

Chan, Tak-Mao; Leung, Jack Kok-Hung; Sun, Yuling; Lai, Kar-Neng; Tsang, Ryan Chi-Wai; Yung, Susan

2003-06-01

Peritoneal dialysis fluid (PDF) containing amino acids has been introduced recently aiming to improve the nutritional status of PD patients. Dextrose-based PDFs have been implicated in progressive functional and structural deterioration of the peritoneal membrane. Limited data are currently available regarding the effect of amino acid-based PDF on the function and ultrastructure of human peritoneal mesothelial cells (HPMCs), which play a critical role in peritoneal membrane pathophysiology. We investigated the effects of two commercially available PDFs, which utilized dextrose (1.5% Dianeal) or amino acids (1.1% Nutrineal) as the osmotic agent, obtained from patients after a 4 h dwell, on HPMC proliferation (MTT assay and cell counting) and viability [lactate dehydrogenase (LDH)release], interleukin-6 (IL-6) secretion (commercial enzyme-linked immunosorbent assay) and ultrastructure (scanning and transmission electron microscopy). Exposure of HPMCs to 1.5% Dianeal reduced cell proliferation, total cellular protein synthesis, IL-6 secretion and cell attachment, but prolonged the cell doubling time on recovery, and increased LDH release (P<0.001, P<0.001, P<0.0001, P<0.0001, P<0.001 and P<0.001, respectively). The 1.1% Nutrineal reduced HPMC proliferation (P<0.001) and increased IL-6 secretion (P<0.0001), but did not affect cell attachment, LDH release, protein synthesis or cell doubling time. Ultrastructural studies of HPMCs exposed to Dianeal showed cell flattening, increased cell surface area, reduced microvilli, and intracellular organelles compatible with dysfunctional mitochondria. In contrast, the ultrastructural morphology of HPMCs was relatively preserved after incubation with Nutrineal. Our results showed that HPMC ultrastructure, viability and protein synthesis were better preserved with amino acid-based PDF, compared with conventional dextrose-based PDF. The significance of IL-6 induction by Nutrineal remains to be elucidated.

Combined effects of lanthanum ion and acid rain on growth, photosynthesis and chloroplast ultrastructure in soybean seedlings.

PubMed

Wen, Kejia; Liang, Chanjuan; Wang, Lihong; Hu, Gang; Zhou, Qing

2011-07-01

Rare earth elements (REEs) have been accumulated in the agricultural environment. Acid rain is a serious environmental issue. In the present work, the effects of lanthanum ion (La(3+)) and acid rain on the growth, photosynthesis and chloroplast ultrastructure in soybean seedlings were investigated using the gas exchange measurements system, chlorophyll fluorometer, transmission electron microscopy and some biochemical techniques. It was found that although the growth and photosynthesis of soybean seedlings treated with the low concentration of La(3+) was improved, the growth and photosynthesis of soybean seedlings were obviously inhibited in the combined treatment with the low concentration of La(3+) and acid rain. At the same time, the chloroplast ultrastructure in the cell of soybean seedlings was destroyed. Under the combined treatment with the high concentration of La(3+) and acid rain, the chloroplast ultrastructure in the cell of soybean seedlings was seriously destroyed, and the growth and of photosynthesis were greatly decreased compared with those of the control, the single treatment with the high concentration of La(3+) and the single treatment with acid rain, respectively. The degree of decrease and destruction on chloroplast ultrastructure depended on the increases in the concentration of La(3+) and acid rain (H(+)). In conclusion, the combined pollution of La(3+) and acid rain obviously destroyed the chloroplast ultrastructure of cell and aggravated the harmful effect of the single La(3+) and acid rain on soybean seedlings. As a new combined pollutant, the harmful effect of REEs ions and acid rain on plant should be paid attention to. Copyright © 2011 Elsevier Ltd. All rights reserved.

Malathion-induced granulosa cell apoptosis in caprine antral follicles: an ultrastructural and flow cytometric analysis.

PubMed

Bhardwaj, Jitender K; Saraf, Priyanka

2014-12-01

Organophosphate pesticides (OPs) like malathion interfere with normal ovarian function resulting in an increased incidence of atresia and granulosa cell apoptosis that plays a consequential role in the loss of ovarian follicles or follicular atresia. The aim of present study was to assess malathion-induced (100 nM) reproductive stress, ultrastructural damage and changes in apoptosis frequency in ovarian granulosa cells of antral follicles. Transmission electron microscopy (TEM) was employed for ultrastructural characterization, oxidative stress was evaluated using thiobarbituric acid reactive substances (TBARS) assay to measure lipid peroxidation, and apoptosis was quantified via flow cytometry. By TEM, apoptosis was identified by the presence of an indented nuclear membrane with blebbing, pyknotic crescent-shaped fragmented nuclei, increased vacuolization, degenerating mitochondria, and lipid droplets. The results indicate a significant increase in malondialdehyde (MDA) level (nmols/g wet tissue) at a 100 nM dose of malathion i.e. 7.57±0.033*, 8.53±0.12*, and 12.87±0.78** at 4, 6, or 8 h, respectively, as compared with controls (6.07±0.033, p<0.01*, p<0.05**) showing a positive correlation between malathion-induced lipid peroxidation and percentage of granulosa cell apoptosis (r=1; p<0.01). The parallel use of these three methods enabled us to determine the role of malathion in inducing apoptosis as a consequence of cytogenetic damage and oxidative stress generated in granulosa cells of antral follicles.

An ultrastructural analysis of the epithelial-fiber interface (EFI) in primate lenses.

PubMed

Kuszak, J R; Novak, L A; Brown, H G

1995-11-01

The purpose of this study was to conduct a comprehensive ultrastructural analysis of the epithelial-fiber interface (EFI) in normal adult primate (Macaque nemestrina and fascicularis; 6-9 years old, n = 10) lenses. Scanning electron microscopy (SEM) was used to initially characterize the gross size, shape and three-dimensional organization of central zone (cz) epithelial cells and the anterior ends of elongating fibers beneath these cells. This fiducial information was essential to properly orient lens pieces in freeze fracture specimen carriers for the production of replicas with unambiguously identifiable EFI. Transmission electron microscopy (TEM) of replicas and thin-sectioned material were used to ultrastructurally analyse the cz EFI. TEM thin-sectioned material was also used to ultrastructurally analyse the pregerminative (pgz), germinative (gz) and transitional zone (tz) EFI. Correlative SEM and TEM of cz EFI components revealed that the apical membrane of both epithelial and elongating fiber cells were irregularly polygonal in shape, and aligned in parallel as smooth, concave-convex surfaces. However, whereas epithelial cell apical surfaces had minimal size variation, elongating fibers were larger and considerably variable in size. Quantitative analysis of > 10000 micron2 cz elongating fiber apical surfaces failed to detect any gap junctions defined in freeze fracture replicas as complementary aggregates of transmembrane proteins (connexons) conjoined across a narrowed extracellular space. However, a comparable frequency of vesicular events was noted in this region as quantified previously in adult and embryonic chick lens. Correlative TEM analysis > 1500 linear micrometers of thin-sectioned EFI from this region confirmed the presence of epithelial-epithelial gap junctions, elongating fiber-elongating fiber gap junctions, and an extreme paucity of epithelial-elongating fiber gap junctions. In contrast, TEM analysis of > 1000 linear micrometers of thin-sectioned pgz, gz and tz EFI, confirmed the presence of epithelial-epithelial gap junctions, elongating fiber-elongating fiber gap junctions, numerous epithelial-elongating fiber adherens junctions and a few epithelial-elongating fiber gap junctions. Thus, the results of this and previous quantitative morphological and physiological studies (electronic and dye coupling) demonstrate that there is limited coupling between cz epithelial cells and underlying elongating fibers. Furthermore, the absence of gap junctional plaques in cz EFI freeze-fracture replicas and either pentalaminar or septalaminar profiles in correlative thin-sections, suggests that this limited coupling could be mediated via isolated gap junction channels. However, the results of this and previous quantitative studies further show that a greater degree of coupling exists across the pgz, gz and tz regions of the EFI and that this coupling is likely to be mediated by gap junction plaques. Finally, this and other studies continue to demonstrate that transcytotic processes play a role in lens physiology at the EFI.

Revealing 3D Ultrastructure and Morphology of Stem Cell Spheroids by Electron Microscopy.

PubMed

Jaros, Josef; Petrov, Michal; Tesarova, Marketa; Hampl, Ales

2017-01-01

Cell culture methods have been developed in efforts to produce biologically relevant systems for developmental and disease modeling, and appropriate analytical tools are essential. Knowledge of ultrastructural characteristics represents the basis to reveal in situ the cellular morphology, cell-cell interactions, organelle distribution, niches in which cells reside, and many more. The traditional method for 3D visualization of ultrastructural components, serial sectioning using transmission electron microscopy (TEM), is very labor-intensive due to contentious TEM slice preparation and subsequent image processing of the whole collection. In this chapter, we present serial block-face scanning electron microscopy, together with complex methodology for spheroid formation, contrasting of cellular compartments, image processing, and 3D visualization. The described technique is effective for detailed morphological analysis of stem cell spheroids, organoids, as well as organotypic cell cultures.

CCDC65 Mutation Causes Primary Ciliary Dyskinesia with Normal Ultrastructure and Hyperkinetic Cilia

PubMed Central

Horani, Amjad; Brody, Steven L.; Ferkol, Thomas W.; Shoseyov, David; Wasserman, Mollie G.; Ta-shma, Asaf; Wilson, Kate S.; Bayly, Philip V.; Amirav, Israel; Cohen-Cymberknoh, Malena; Dutcher, Susan K.; Elpeleg, Orly; Kerem, Eitan

2013-01-01

Background Primary ciliary dyskinesia (PCD) is a genetic disorder characterized by impaired ciliary function, leading to chronic sinopulmonary disease. The genetic causes of PCD are still evolving, while the diagnosis is often dependent on finding a ciliary ultrastructural abnormality and immotile cilia. Here we report a novel gene associated with PCD but without ciliary ultrastructural abnormalities evident by transmission electron microscopy, but with dyskinetic cilia beating. Methods Genetic linkage analysis was performed in a family with a PCD subject. Gene expression was studied in Chlamydomonas reinhardtii and human airway epithelial cells, using RNA assays and immunostaining. The phenotypic effects of candidate gene mutations were determined in primary culture human tracheobronchial epithelial cells transduced with gene targeted shRNA sequences. Video-microscopy was used to evaluate cilia motion. Results A single novel mutation in CCDC65, which created a termination codon at position 293, was identified in a subject with typical clinical features of PCD. CCDC65, an orthologue of the Chlamydomonas nexin-dynein regulatory complex protein DRC2, was localized to the cilia of normal nasal epithelial cells but was absent in those from the proband. CCDC65 expression was up-regulated during ciliogenesis in cultured airway epithelial cells, as was DRC2 in C. reinhardtii following deflagellation. Nasal epithelial cells from the affected individual and CCDC65-specific shRNA transduced normal airway epithelial cells had stiff and dyskinetic cilia beating patterns compared to control cells. Moreover, Gas8, a nexin-dynein regulatory complex component previously identified to associate with CCDC65, was absent in airway cells from the PCD subject and CCDC65-silenced cells. Conclusion Mutation in CCDC65, a nexin-dynein regulatory complex member, resulted in a frameshift mutation and PCD. The affected individual had altered cilia beating patterns, and no detectable ultrastructural defects of the ciliary axoneme, emphasizing the role of the nexin-dynein regulatory complex and the limitations of certain methods for PCD diagnosis. PMID:23991085

Long-term sulphur starvation of Arabidopsis thaliana modifies mitochondrial ultrastructure and activity and changes tissue energy and redox status.

PubMed

Ostaszewska, Monika; Juszczuk, Izabela M; Kołodziejek, Izabella; Rychter, Anna M

2014-04-15

Sulphur, as a constituent of amino acids (cysteine and methionine), iron-sulphur clusters, proteins, membrane sulpholipids, glutathione, glucosinolates, coenzymes, and auxin precursors, is essential for plant growth and development. Absence or low sulphur concentration in the soil results in severe growth retardation. Arabidopsis thaliana plants grown hydroponically for nine weeks on Knop nutrient medium without sulphur showed morphological symptoms of sulphur deficiency. The purpose of our study was to investigate changes that mitochondria undergo and the role of the highly branched respiratory chain in survival during sulphur deficiency stress. Ultrastructure analysis of leaf mesophyll cells of sulphur-deficient Arabidopsis showed heterogeneity of mitochondria; some of them were not altered, but the majority had swollen morphology. Dilated mitochondria displayed a lower matrix density and fewer cristae compared to control mitochondria. Disintegration of the inner and outer membranes of some mitochondria from the leaves of sulphur-deficient plants was observed. On the contrary, chloroplast ultrastructure was not affected. Sulphur deficiency changed the respiratory activity of tissues and isolated mitochondria; Complex I and IV capacities and phosphorylation rates were lower, but external NAD(P)H dehydrogenase activity increased. Higher external NAD(P)H dehydrogenase activity corresponded to increased cell redox level with doubled NADH/NAD ratio in the leaf and root tissues. Sulphur deficiency modified energy status in the tissues of Arabidopsis plants. The total concentration of adenylates (expressed as ATP+ADP), measured in the light, was lower in the leaves and roots of sulphur-deficient plants than in the controls, which was mainly due to the severely decreased ATP levels. We show that the changes in mitochondrial ultrastructure are compensated by the modifications in respiratory chain activity. Although mitochondria of Arabidopsis tissues are affected by sulphur deficiency, their metabolic and structural features, which readily reach new homeostasis, make these organelles crucial for adaptation of plants to survive sulphur deficiency. Copyright © 2013 Elsevier GmbH. All rights reserved.

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

PubMed

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.

Mueller matrix approach for probing multifractality in the underlying anisotropic connective tissue

NASA Astrophysics Data System (ADS)

Das, Nandan Kumar; Dey, Rajib; Ghosh, Nirmalya

2016-09-01

Spatial variation of refractive index (RI) in connective tissues exhibits multifractality, which encodes useful morphological and ultrastructural information about the disease. We present a spectral Mueller matrix (MM)-based approach in combination with multifractal detrended fluctuation analysis (MFDFA) to exclusively pick out the signature of the underlying connective tissue multifractality through the superficial epithelium layer. The method is based on inverse analysis on selected spectral scattering MM elements encoding the birefringence information on the anisotropic connective tissue. The light scattering spectra corresponding to the birefringence carrying MM elements are then subjected to the Born approximation-based Fourier domain preprocessing to extract ultrastructural RI fluctuations of anisotropic tissue. The extracted RI fluctuations are subsequently analyzed via MFDFA to yield the multifractal tissue parameters. The approach was experimentally validated on a simple tissue model comprising of TiO2 as scatterers of the superficial isotropic layer and rat tail collagen as an underlying anisotropic layer. Finally, the method enabled probing of precancer-related subtle alterations in underlying connective tissue ultrastructural multifractality from intact tissues.

[Ultrastructural changes of myelinated fibers in the brain in continuous and attack-like paranoid schizophrenia].

PubMed

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.

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

PubMed

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 responsible for low concentration MES specifically inducing male sterility. A simple action model of CHA-MES inducing male sterility in B. napus was proposed. These results will help us to understand the mechanism of MES inducing male sterility at low concentration, and might provide some potential targets for developing new male sterility inducing CHAs and for genetic manipulation in rapeseed breeding.

Microscopic and ultrastructural features in Wolcott-Rallison syndrome, a permanent neonatal diabetes mellitus: about two autopsy cases.

PubMed

Collardeau-Frachon, Sophie; Vasiljevic, Alexandre; Jouvet, Anne; Bouvier, Raymonde; Senée, Valérie; Nicolino, Marc

2015-11-01

Wolcott-Rallison syndrome (WRS) is a rare autosomal recessive disorder characterized by the association of permanent neonatal or early-infancy insulin-dependent diabetes, multiple bone dysplasia, hepatic dysfunction, and growth retardation. All clinical manifestations result from gene mutations encoding pancreatic endoplasmic reticulum eIF2 α kinase (PERK), an endoplasmic reticulum transmembrane protein that plays a role in the unfolded protein response. Histological and ultrastructural lesions of bone and pancreas have been described in animal models and WRS patients. However, histological and ultrastructural findings of other organs, especially of the liver, are lacking. Autopsy specimens from two pediatric patients with WRS were analyzed. An immunohistochemical study was performed on the pancreas. An ultrastructural study was realized from samples of liver, pancreas, kidney, and myocardium. Our findings were compared with those of the literature and correlated with the molecular data. Hepatocytes and pancreatic exocrine cells exhibited very peculiar features of necrosis suggestive of secondary changes because of endoplasmic reticulum overload. Steatosis occurred in renal tubular cells, hepatocytes, and myocardial fibers. Abnormal mitochondria were noted in renal and myocardial fibers. Pancreas islets were characterized by a marked reduction in the number of insulin-secreting β cells. The histological and ultrastructural features that occur in WRS are directly or indirectly linked to endoplasmic reticulum (ER) dysfunction and can explain the peculiar phenotype of this syndrome. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

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

PubMed Central

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

2015-01-01

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 formation of trout are proposed. PMID:26467239

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

PubMed

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 formation of trout are proposed. © 2015 Anatomical Society.

The ultrastructure and processing properties of Straumann Bone Ceramic and NanoBone.

PubMed

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.

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

NASA Astrophysics Data System (ADS)

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.

Lead accumulation and tolerance of Moso bamboo (Phyllostachys pubescens) seedlings: applications of phytoremediation*

PubMed Central

Liu, Dan; Li, Song; Islam, Ejazul; Chen, Jun-ren; Wu, Jia-sen; Ye, Zheng-qian; Peng, Dan-li; Yan, Wen-bo; Lu, Kou-ping

2015-01-01

A hydroponics experiment was aimed at identifying the lead (Pb) tolerance and phytoremediation potential of Moso bamboo (Phyllostachys pubescens) seedlings grown under different Pb treatments. Experimental results indicated that at the highest Pb concentration (400 μmol/L), the growth of bamboo seedlings was inhibited and Pb concentrations in leaves, stems, and roots reached the maximum of 148.8, 482.2, and 4282.8 mg/kg, respectively. Scanning electron microscopy revealed that the excessive Pb caused decreased stomatal opening, formation of abundant inclusions in roots, and just a few inclusions in stems. The ultrastructural analysis using transmission electron microscopy revealed that the addition of excessive Pb caused abnormally shaped chloroplasts, disappearance of endoplasmic reticulum, shrinkage of nucleus and nucleolus, and loss of thylakoid membranes. Although ultrastructural analysis revealed some internal damage, even the plants exposed to 400 μmol/L Pb survived and no visual Pb toxicity symptoms such as necrosis and chlorosis were observed in these plants. Even at the highest Pb treatment, no significant difference was observed for the dry weight of stem compared with controls. It is suggested that use of Moso bamboo as an experimental material provides a new perspective for remediation of heavy metal contaminated soil owing to its high metal tolerance and greater biomass. PMID:25644467

Effects of corticosteroids and hyaluronic acid on torn rotator cuff tendons in vitro and in rats.

PubMed

Nakamura, Hidehiro; Gotoh, Masafumi; Kanazawa, Tomonoshin; Ohta, Keisuke; Nakamura, Keiichirou; Honda, Hirokazu; Ohzono, Hiroki; Shimokobe, Hisao; Mitsui, Yasuhiro; Shirachi, Isao; Okawa, Takahiro; Higuchi, Fujio; Shirahama, Masahiro; Shiba, Naoto; Matsueda, Satoko

2015-10-01

Corticosteroids (CS) or hyaluronic acid (HA) is used in subacromial injection for the conservative treatment of rotator cuff tears (RCT); this study addresses the question of how CS and HA affect the tendon tissue and fibroblasts in vitro and in rats. Cell proliferation assays were performed in human tendon fibroblasts from RCT. Rats underwent surgery to create RCT, and the surgical sites were injected with CS or HA. The rotator cuff tendons were subjected to biomechanical testing, microscopic and immunohistochemical analysis of proliferating cell nuclear antigen (PCNA), and ultrastructural analysis. Cell proliferation was significantly decreased with CS in vitro (p < 0.05). Maximal load of CS-treated tendons was significantly decreased compared with that of HA-treated tendons (p < 0.05), as well as PCNA(+) cells at 2 weeks (p < 0.05). Ultrastructural observations of the CS-treated rats detected apoptosis of tendon fibroblasts 24 h after surgery. Histological and biomechanical data 4 weeks after surgery were not significant among the three groups. Unlike HA, CS caused cell death, and inhibition of the proliferation of tendon fibroblasts, leading to a delay of tendon healing involved and a subsequent decrease of biomechanical strength at the surgical site. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Demonstration of a focused ion-beam cross-sectioning technique for ultrastructural examination of resin-dentin interfaces.

PubMed

Van Meerbeek, B; Conn, L J; Duke, E S; Schraub, D; Ghafghaichi, F

1995-03-01

focused ion-beam (FIB) etching, commonly used as a cross-sectioning technique for failure analysis of semiconductor devices, has recently been applied to biological tissues to expose their ultrastructure for examination. It was the aim of this investigation to determine the practical utility of FIB to cross-section resin-dentin interfaces in order to morphologically evaluate the completeness of resin penetration into the exposed collagen scaffold at the resin-dentin bond interface. Two representative commercially available dentin adhesive systems were bonded to mid-coronal dentin. After appropriate fixation and dehydration of the resin-bonded dentin samples, a scanned focused ion-beam of a few tens of nano-meters in diameter was used to cross=section the resin-dentin interface. Examination of the interfacial ultrastructure was accomplished using a field-emission SEM. Results indicate possible artifact production at the cross-sectioned interface, hiding its actual ultrastructure, probably due to a heat-effect with possible recrystallization. Further studies of FIB are needed to optimize its usefulness for resin-dentin interface examinations and other biological tissue applications. Complete resin saturation of the demineralized dentin surface-layer has been claimed to be the key factor for a long-lasting resin-dentin bond. A "clean" artifact-free micro-cross-sectioning technique may provide indisputable ultra-structural information about the depth of resin penetration into the demineralized zone. Such a test would be useful in the development of dentin adhesive systems.

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

PubMed

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 pathways to direct gene testing and has reinforced the need for accurate phenotyping before undertaking further genetic investigations. The morphometric assessment of elastic fibre area fraction and ultrastructural findings from this study have provided us with a better understanding of OI and insights into the possible mechanism of these changes in the skin. Correlation of skin findings with the clinical phenotype as well as genetic testing has enabled understanding of the molecular pathogenesis and translation of changes at the genomic level to clinical phenotype.

Cryo-planing of frozen-hydrated samples using cryo triple ion gun milling (CryoTIGM™).

PubMed

Chang, Irene Y T; Joester, Derk

2015-12-01

Cryo-SEM is a high throughput technique for imaging biological ultrastructure in its most pristine state, i.e. without chemical fixation, embedding, or drying. Freeze fracture is routinely used to prepare internal surfaces for cryo-SEM imaging. However, the propagation of the fracture plane is highly dependent on sample properties, and the resulting surface frequently shows substantial topography, which can complicate image analysis and interpretation. We have developed a broad ion beam milling technique, called cryogenic triple ion gun milling (CryoTIGM™ ['krī-ə-,tīm]), for cryo-planing frozen-hydrated biological specimens. Comparing sample preparation by CryoTIGM™ and freeze fracture in three model systems, Baker's yeast, mouse liver tissue, and whole sea urchin embryos, we find that CryoTIGM™ yields very large (∼700,000 μm(2)) and smooth sections that present ultrastructural details at similar or better quality than freeze-fractured samples. A particular strength of CryoTIGM™ is the ability to section samples with hard-soft contrast such as brittle calcite (CaCO3) spicules in the sea urchin embryo. Copyright © 2015 Elsevier Inc. All rights reserved.

A comparative ultrastructural analysis of spermatozoa in Pleurodema (Anura, Leptodactylidae, Leiuperinae).

PubMed

Cruz, Julio C; Ferraro, Daiana P; Farías, Alejandro; Santos, Julio S; Recco-Pimentel, Shirlei M; Faivovich, Julián; Hermida, Gladys N

2016-07-01

This study describes the spermatozoa of 10 of the 15 species of the Neotropical frog genus Pleurodema through transmission electron microscopy. The diversity of oviposition modes coupled with a recent phylogenetic hypothesis of Pleurodema makes it an interesting group for the study of ultrastructural sperm evolution in relation to fertilization environment and egg-clutch structure. We found that Pleurodema has an unusual variability in sperm morphology. The more variable structures were the acrosomal complex, the midpiece, and the tail. The acrosomal complex has all the structures commonly reported in hyloid frogs but with different degree of development of the subacrosomal cone. Regarding the midpiece, the variability is given by the presence or absence of the mitochondrial collar. Finally, the tail is the most variable structure, ranging from single (only axoneme) to more complex (presence of paraxonemal rod, cytoplasmic sheath, and undulating membrane), with the absence of the typical axial fiber present in hyloid frogs, also shared with some other genera of Leiuperinae. J. Morphol. 277:957-977, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Ultrastructure Organization of Human Trabeculae Assessed by 3D sSAXS and Relation to Bone Microarchitecture

PubMed Central

Guizar-Sicairos, Manuel; Gschwend, Oliver; Hangartner, Peter; Bunk, Oliver; Müller, Ralph; Schneider, Philipp

2016-01-01

Although the organization of bone ultrastructure, i.e. the orientation and arrangement of the mineralized collagen fibrils, has been in the focus of research for many years for cortical bone, and many models on the osteonal arrangement have been proposed, limited attention has been paid to trabecular bone ultrastructure. This is surprising because trabeculae play a crucial role for the mechanical strength of several bone sites, including the vertebrae and the femoral head. On this account, we first validated a recently developed method (3D sSAXS or 3D scanning small-angle X-ray scattering) for investigating bone ultrastructure in a quantitative and spatially resolved way, using conventional linearly polarized light microscopy as a gold standard. While both methods are used to analyze thin tissue sections, in contrast to polarized light microscopy, 3D sSAXS has the important advantage that it provides 3D information on the orientation and arrangement of bone ultrastructure. In this first study of its kind, we used 3D sSAXS to investigate the ultrastructural organization of 22 vertebral trabeculae of different alignment, types and sizes, obtained from 4 subjects of different ages. Maps of ultrastructure orientation and arrangement of the trabeculae were retrieved by stacking information from consecutive 20-μm-thick bone sections. The organization of the ultrastructure was analyzed in relation to trabecular microarchitecture obtained from computed tomography and to relevant parameters such as distance to trabecular surface, local curvature or local bone mineralization. We found that (i) ultrastructure organization is similar for all investigated trabeculae independent of their particular characteristics, (ii) bone ultrastructure exhibiting a high degree of orientation was arranged in domains, (iii) highly oriented ultrastructural areas were located closer to the bone surface, (iv) the ultrastructure of the human trabecular bone specimens followed the microarchitecture, being oriented mostly parallel to bone surface, and (v) local surface curvature seems to have an effect on the ultrastructure organization. Further studies that investigate bone ultrastructure orientation and arrangement are needed in order to understand its organization and consequently its relation to bone biology and mechanics. PMID:27547973

Ultrastructural findings in noncompaction prevail with neuromuscular disorders.

PubMed

Finsterer, Josef; Stöllberger, Claudia

2013-01-01

Little is known about the ultrastructural abnormalities of left ventricular hypertrabeculation/noncompaction (LVHT). This literature review aimed to summarize and discuss ultrastructural abnormalities described in LVHT so far. The literature search was conducted via MEDLINE using the search terms 'non-compaction', 'noncompaction', 'left ventricular hypertrabeculation', 'spongy myocardium' in combination with the terms 'ultra-structural', or 'electron microscopy'. Altogether, 11 studies reporting ultrastructural investigations of LVHT were retrieved. In these 11 studies, data on 13 patients with LVHT were presented. Ultrastructural abnormalities found in these study patients were generally nonspecific and included an increase in the number of mitochondria (n = 3), abnormally shaped mitochondria (n = 2), distorted cristae (n = 3), sarcomeric derangement (n = 3), immature cardiomyocytes (n = 1), lipid-like inclusions (n = 1), enlarged interstitial spaces (n = 1), increased interstitial collagen (n = 1), or increased glycogen (n = 1). The morphological abnormalities were most prominent in patients with a neuromuscular disorder like Barth syndrome or mitochondrial myopathy. Only in few patients with LVHT, ultrastructural investigations have been performed so far. Ultrastructural abnormalities in LVHT are nonspecific and most prominent in patients with a neuromuscular disorder. There is a strong need to carry out thorough ultrastructural investigations of LVHT to contribute to the understanding of this still unexplained myocardial abnormality.

Ultrastructural analysis of Phytomonas species from Euphorbia pinea reveals trans-cytoplasmic filaments 10 nm in diameter.

PubMed

Page, A M; Lagnado, J R

2000-10-01

Phytomonas sp. derived from Euphorbia pinea are digenetic plant trypanosomes that are transmitted by the squashbug Stenocephalus agilis and exist exclusively as promastigotes. The stable sub-pellicular microtubular array, the flagellar axoneme and the paraflagellar rod represent the major cytoskeletal components common to all trypanosomes. The work described in this paper examines in detail the ultrastructural morphology of the organism and highlights a number of novel structural features, and in particular, the presence of some detergent-resistant proteins which take the form of bundles of trans-cytoplasmic filaments of ca. 10 nm in diameter, seen in cells from both log- and stationary-phase cultures. The ultrastructural morphology and immunological cross-reactivity of these filaments are described, and their relationship to filamentous bundles previously reported in stationary-phase cultures of Crithidia fasciculata and to intermediate filaments of animal cells is discussed.

Clinical Features and Associated Likelihood of Primary Ciliary Dyskinesia in Children and Adolescents.

PubMed

Leigh, Margaret W; Ferkol, Thomas W; Davis, Stephanie D; Lee, Hye-Seung; Rosenfeld, Margaret; Dell, Sharon D; Sagel, Scott D; Milla, Carlos; Olivier, Kenneth N; Sullivan, Kelli M; Zariwala, Maimoona A; Pittman, Jessica E; Shapiro, Adam J; Carson, Johnny L; Krischer, Jeffrey; Hazucha, Milan J; Knowles, Michael R

2016-08-01

Primary ciliary dyskinesia (PCD), a genetically heterogeneous, recessive disorder of motile cilia, is associated with distinct clinical features. Diagnostic tests, including ultrastructural analysis of cilia, nasal nitric oxide measurements, and molecular testing for mutations in PCD genes, have inherent limitations. To define a statistically valid combination of systematically defined clinical features that strongly associates with PCD in children and adolescents. Investigators at seven North American sites in the Genetic Disorders of Mucociliary Clearance Consortium prospectively and systematically assessed individuals (aged 0-18 yr) referred due to high suspicion for PCD. The investigators defined specific clinical questions for the clinical report form based on expert opinion. Diagnostic testing was performed using standardized protocols and included nasal nitric oxide measurement, ciliary biopsy for ultrastructural analysis of cilia, and molecular genetic testing for PCD-associated genes. Final diagnoses were assigned as "definite PCD" (hallmark ultrastructural defects and/or two mutations in a PCD-associated gene), "probable/possible PCD" (no ultrastructural defect or genetic diagnosis, but compatible clinical features and nasal nitric oxide level in PCD range), and "other diagnosis or undefined." Criteria were developed to define early childhood clinical features on the basis of responses to multiple specific queries. Each defined feature was tested by logistic regression. Sensitivity and specificity analyses were conducted to define the most robust set of clinical features associated with PCD. From 534 participants 18 years of age and younger, 205 were identified as having "definite PCD" (including 164 with two mutations in a PCD-associated gene), 187 were categorized as "other diagnosis or undefined," and 142 were defined as having "probable/possible PCD." Participants with "definite PCD" were compared with the "other diagnosis or undefined" group. Four criteria-defined clinical features were statistically predictive of PCD: laterality defect; unexplained neonatal respiratory distress; early-onset, year-round nasal congestion; and early-onset, year-round wet cough (adjusted odds ratios of 7.7, 6.6, 3.4, and 3.1, respectively). The sensitivity and specificity based on the number of criteria-defined clinical features were four features, 0.21 and 0.99, respectively; three features, 0.50 and 0.96, respectively; and two features, 0.80 and 0.72, respectively. Systematically defined early clinical features could help identify children, including infants, likely to have PCD. Clinical trial registered with ClinicalTrials.gov (NCT00323167).

An ultrastructural analysis of platelets, erythrocytes, white blood cells, and fibrin network in systemic lupus erythematosus.

PubMed

Pretorius, Etheresia; du Plooy, Jenny; Soma, Prashilla; Gasparyan, Armen Yuri

2014-07-01

The study suggests that patients with systemic lupus erythematosus (SLE) present with distinct inflammatory ultrastructural changes such as platelets blebbing, generation of platelet-derived microparticles, spontaneous formation of massive fibrin network and fusion of the erythrocytes membranes. Lupoid platelets actively interact with other inflammatory cells, particularly with white blood cells (WBCs), and the massive fibrin network facilitates such an interaction. It is possible that the concerted actions of platelets, erythrocytes and WBC, caught in the inflammatory fibrin network, predispose to pro-thrombotic states in patients with SLE.

Ultrastructural characterization of the new NG97ht human-derived glioma cell line using two different electron microscopy technical procedures.

PubMed

Machado, Camila Maria Longo; Zorzeto, Tatiane Queiroz; Bianco, Juares E Romero; Rosa, Renata Giardini; Genari, Selma Candelaria; Joazeiro, Paulo Pinto; Verinaud, Liana

2009-04-01

On the basis of transmission electron microscopy observations in tumor cell lines, oncologists have made innumerous diagnostic and therapeutical progresses. Following this path, the UNICAMP immunopathologies laboratory established the NG97 cell line derived from a human astrocytoma grade III, which when injected to the athymic nude mouse flank developed a grade IV astrocytoma. In this study, we focused on ultrastructural characterization of the NG97 cells after being recovered from xenotransplant (NG97ht). These cells in culture were assayed by two different electron microscopy procedures to characterize ultrastructures related to grade IV astrocytomas and to observe their structures through cell subcultivation. Additionally, comparative morphological descriptions of different cell passages in these technical procedures could be a useful tool for improving electron microscopy cell lineage protocols. Results from many cell passage observations showed ultrastructural similarities, which suggest malignant and glioblastoma phenotypes. In the first procedure, NG97ht cells were harvested and then incorporated into agarose before subjecting them to electron microscopy protocols, whereas in the second one, monolayer cells grew first on cover slides. Comparison among protocols revealed that organelles, cytoplasmatic extensions, spatial conformation of filopodia, and cell attachment to substrate were more preserved in the second procedure. Furthermore, in this latter procedure, a unique ellipsoidal structure was observed, which was already described when dealing with gliosarcoma cell line elsewhere. Therefore, these analyses demonstrated a morphological characterization of a new NG97ht cell line using electron transmission microscopy. Moreover, it has been shown that the second procedure provides more detailed information compared with the first.

[The effect of 18β-glycyrrhetinic acid on tight junctions of the nasal mucosa epithelial cells in rat models with allergic rhinitis].

PubMed

Ma, Yi; Gui, Yan; Wang, Youhu; Xi, Kehu; Chen, Xiaowan; Zhang, Fuhong; Ma, Chunxia; Hong, Hao; Liu, Xiangyi; Jiang, Ying; Dong, Ming; Yang, Guijun; Zhang, Xiaobing

2014-10-01

To observe 18β-glycyrrhetinic acid (GA) impact on ultrastructure of tight junctions (TJs) of nasal mucosa epithelial cells in rats models of allergic rhinitis (AR). Ninety-six Wistar rats were randomly divided into control group, model group, loratadine group, and 18β-glycyrrhetinic acid group, and each group had 24 rats. Ovalbumin was used to establish a rat AR model. The behavioral changes and the tight junctions of nasal epithelial were observed and compared in different groups after 2,4,6 and 10 weeks intervention. The length of TJs in allergic rhinitis model became shorter, electron-high-density plasma membrane became thicker, number of the integration loci reduced and gap of TJs widened or even ruptured. With the consistent effect of allergens,the changes of TJs in the model group aggravated gradually,and the changes of ultrastructure of TJs in 18β-glycyrrhetinic acid group was relieved apparently compared to model group and even were close to the control model with time. 18β-glycyrrhetinic acid can recover the ultrastructure of the tight junctions of AR rat nasal epithelial cells.

INCOMPLETE REPAIR OF RETINAL STRUCTURE AFTER VITRECTOMY WITH INTERNAL LIMITING MEMBRANE PEELING.

PubMed

Hisatomi, Toshio; Tachibana, Takashi; Notomi, Shoji; Nakatake, Shunji; Fujiwara, Kohta; Murakami, Yusuke; Ikeda, Yasuhiro; Yoshida, Shigeo; Enaida, Hiroshi; Murata, Toshinori; Sakamoto, Taiji; Sonoda, Koh-Hei; Ishibashi, Tatsuro

2017-08-01

To examine retinal changes after vitrectomy with internal limiting membrane (ILM) peeling, we used a cynomolgus monkey model and focused on surgical damages of ILM peeling for long observational period of 3 years. Vitrectomy was performed followed by ILM peeling similar to clinical settings in humans. Ultrastructural changes of the retina were investigated by light, transmission, and scanning electron microscopy at 3 months and 3 years after ILM peeling. Ultrastructural study showed that the ILM peeled area was still clearly recognized after 3 years. The Müller cell processes covered most of the retina; however, the nerve fiber layer was partly uncovered and exposed to the vitreous space. The arcuate linear nerve fiber bundles were observed as comparable with dissociated optic nerve fiber layer appearance. Small round retinal surface defects were also observed around macula, resembling the dimple sign. Forceps-related retinal thinning was also found on the edge of ILM peeling, where we started peeling with fine forceps. The ultrastructural studies showed that most of ILM peeling area was covered with glial cells during wound healing processes. Retinal changes were found comparable with dissociated optic nerve fiber layer appearance or dimple sign, which were clinically observed with optical coherence tomography.

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

PubMed Central

Maier, Christopher W; Long, Jeffrey G; Hemminger, Bradley M; Giddings, Morgan C

2009-01-01

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 Ultra-Structure offers substantial benefits for biological information systems, the largest being the integration of diverse information sources into a common framework. This facilitates systems biology research by integrating data from disparate high-throughput techniques. It also enables us to readily incorporate new data types, sources, and domain knowledge with no change to the database structure or associated computer code. Ultra-Structure may be a significant step towards solving the hard problem of data management and integration in the systems biology era. PMID:19691849

Ultrastructural characterization of pulmonary neoplasms. II. The role of electron microscopy in characterization of uncommon epithelial pulmonary neoplasms, metastatic neoplasms to and from lung, and other tumors, including mesenchymal neoplasms.

PubMed

Herrera, G A; Alexander, C B; Jones, J M

1985-01-01

Ultrastructural analysis through better resolution adds significant information to the evaluation and classification of primary pulmonary neoplasms. Light microscopy is limited in the evaluation of lung neoplasms. In some cases the light microscopic appearance may be entirely misleading, whereas in others it is inconclusive. Immunocytochemistry provides information on cytoplasmic differentiation of various tumors and hence more data on their corresponding phenotypes. The data from immunocytochemistry without corresponding objective electron microscopic evaluation may be very difficult to interpret. Correlation of historical, gross, light, electron microscopic, and immunocytochemical data is essential for a final accurate diagnosis (fig. 20). Fine needle aspiration of pulmonary neoplasms is becoming very fashionable and a diagnosis, including type of neoplasm, is expected on the basis of examination of a limited number of cells which further emphasizes the importance of ultrastructural characterization in helping to establish an accurate diagnosis [63-69]. The current classification of pulmonary neoplasms may need to be modified in the near future to incorporate the newly created data [70-72]. At the present time, there appears to be, at least, a need for a 'double standard', as Sobin [73] has suggested, which would permit the evaluation of the biologic significance of the ultrastructural and immunocytochemical findings (as applied to classification of neoplasms) in an effort to derive meaningful clinicopathologic correlations. Figure 20 emphasizes the additive role which should be played by the various diagnostic modalities to enable a morphologic assessment which would be an accurate predictor of biologic behavior. With an accurate assessment of biologic behavior, a more appropriate and rational approach for therapy is possible. There is also an important role for ultrastructural analysis in metastatic pleural and pulmonary neoplasms, primarily adenocarcinomas, as well as in the differential diagnosis of pulmonary neoplasms versus other tumors that may be similar in histological appearance. The role of ultrastructure in mesenchymal neoplasms is also crucial in defining specific neoplastic cell populations and in some cases in the differentiation from other non-mesenchymal tumors. It seems that routine electron microscopic examination of pulmonary neoplasms provides additional information that may be of great value in the management of patients and in understanding the differentiation, and perhaps histogenesis, of pulmonary neoplasms.(ABSTRACT TRUNCATED AT 400 WORDS)

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

PubMed

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.

Remodeling of the rat distal colon in diabetes: function and ultrastructure.

PubMed

Siegman, Marion J; Eto, Masumi; Butler, Thomas M

2016-01-15

This study seeks to define and explain remodeling of the distal colon in the streptozotocin (STZ)-treated rat model of diabetes through analysis of resting and active length dependence of force production, chemical composition, and ultrastructure. Compared with untreated controls, the passive stiffness on extension of the diabetic muscle is high, and active force produced at short muscle lengths is amplified but is limited by an internal resistance to shortening. The latter are accounted for by a significant increase in collagen type 1, with no changes in types 3 and 4. In the diabetic colon, ultrastructural studies show unique, conspicuous pockets of collagen among muscle cells, in addition to a thickened basement membrane and an extracellular space filled with collagen fibers and various fibrils. Measurements of DNA and total protein content revealed that the diabetic colon underwent hypertrophy, along with a proportional increase in actin and myosin contents, with no change in the actin-to-myosin ratio. Active force production per cross-sectional area was not different in the diabetic and normal muscles, consistent with the proportionality of changes in contractile proteins. The stiffness and the limit to shortening of the diabetic colon were significantly reduced by treatment with the glycation breaker alagebrium chloride (ALT-711), with no change in collagen contents. Functionally, this study shows that, in diabetes, the production of collagen type 1 and glycation increase stiffness, which limits distensibility on filling and limits shortening and expulsion of contents, both of which can be alleviated by treatment with ALT-711. Copyright © 2016 the American Physiological Society.

Effect of insulin-like growth factor-1 on corneal surface ultrastructure and nerve regeneration of rabbit eyes after laser in situ keratomileusis.

PubMed

Wang, Chunyan; Peng, Yanli; Pan, Shuling; Li, Li

2014-01-13

To explore the effect of insulin-like growth factor-1 (IGF-1) on corneal surface ultrastructure and nerve regeneration in rabbit models after laser in situ keratomileusis (LASIK). Forty-two healthy New Zealand white rabbits were divided into two groups, the IGF-1 group and the control group, and LASIK surgery was performed. The corneal surface ultrastructure was observed by transmission electron microscopy, and the nerve regeneration was evaluated by counting the newly regenerated nerves at 1 d, 1 w, 2 w, 1 m, 3 m and 6 m after surgery. Dry eye parameters, including the Schirmer I test and tear break-up time, were examined at all time points. The examination of corneal ultrastructure showed that the number of corneal epithelial microvilli in the IGF-1 group was significantly higher than that in the normal saline (NS) group except in the second postoperative week (p<0.05). The observation of corneal nerve regeneration showed that the number of regenerated nerve fibers in the IGF-1 group was higher than the control group at all time points (p<0.05). The parameters of dry eye were significantly higher in the IGF-1 group compared to the control group at all time points except at 1d and 6m after LASIK. IGF-1 can effectively accelerate the early repair of corneal surface ultrastructure and nerve regeneration after LASIK and relieve dry eye symptoms in rabbit eyes. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

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

PubMed Central

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

Phytomonas serpens: cysteine peptidase inhibitors interfere with growth, ultrastructure and host adhesion.

PubMed

Santos, André L S; d'Avila-Levy, Claudia M; Dias, Felipe A; Ribeiro, Rachel O; Pereira, Fernanda M; Elias, Camila G R; Souto-Padrón, Thaïs; Lopes, Angela H C S; Alviano, Celuta S; Branquinha, Marta H; Soares, Rosangela M A

2006-01-01

In this study, we report the ultrastructural and growth alterations caused by cysteine peptidase inhibitors on the plant trypanosomatid Phytomonas serpens. We showed that the cysteine peptidase inhibitors at 10 microM were able to arrest cellular growth as well as promote alterations in the cell morphology, including the parasites becoming short and round. Additionally, iodoacetamide induced ultrastructural alterations, such as disintegration of cytoplasmic organelles, swelling of the nucleus and kinetoplast-mitochondrion complex, which culminated in parasite death. Leupeptin and antipain induced the appearance of microvillar extensions and blebs on the cytoplasmic membrane, resembling a shedding process. A 40 kDa cysteine peptidase was detected in hydrophobic and hydrophilic phases of P. serpens cells after Triton X-114 extraction. Additionally, we have shown through immunoblotting that anti-cruzipain polyclonal antibodies recognised two major polypeptides in P. serpens, including a 40 kDa component. Flow cytometry analysis confirmed that this cruzipain-like protein has a location on the cell surface. Ultrastructural immunocytochemical analysis demonstrated the presence of the cruzipain-like protein on the surface and in small membrane fragments released from leupeptin-treated parasites. Furthermore, the involvement of cysteine peptidases of P. serpens in the interaction with explanted salivary glands of the phytophagous insect Oncopeltus fasciatus was also investigated. When P. serpens cells were pre-treated with either cysteine peptidase inhibitors or anti-cruzipain antibody, a significant reduction of the interaction process was observed. Collectively, these results suggest that cysteine peptidases participate in several biological processes in P. serpens including cell growth and interaction with the invertebrate vector.

The defensive secretion of Carabus lefebvrei Dejean 1826 pupa (Coleoptera, Carabidae): gland ultrastructure and chemical identification.

PubMed

Giglio, Anita; Brandmayr, Pietro; Dalpozzo, Renato; Sindona, Giovanni; Tagarelli, Antonio; Talarico, Federica; Brandmayr, Tullia Zetto; Ferrero, Enrico A

2009-05-01

This study documents the defensive function of flavored humor secreted by the abdominal glands of Carabus lefebvrei pupae. The morphology and the ultrastructure of these glands were described and the volatile compounds of glands secretion were identified by gas chromatography/mass spectrometry. The ultrastructure analysis shows an acinose complex formed by about 50 clusters. Each cluster has 20 glandular units and the unit-composed of one secretory and one canal cell lying along a duct-belongs to the class 3 cell type of Quennedey (1998). In the cytoplasm, the secretory cell contains abundant rough endoplasmatic reticula, glycogen granules, numerous mitochondria, and many well-developed Golgi complexes producing electron-dense secretory granules. Mitochondria are large, elongated, and often adjoining electronlucent vesicles. The kind and the origin of secretory granules varying in size and density were discussed. The chemical analysis of the gland secretion revealed the presence of a mixture of low molecular weight terpenes, ketones, aldehydes, alcohols, esters, and carboxylic acids. Monoterpenes, especially linalool, were the major products. We supposed that ketones, aldehydes, alcohols, esters, and carboxylic acids have a deterrent function against the predators and monoterpenes provide a prophylaxis function against pathogens. (c) 2008 Wiley-Liss, Inc.

Ultrastructure of poison glands of South American frogs: a comparison between Physalaemus albonotatus and Leptodactylus chaquensis (Anura: Leptodactylidae).

PubMed

Alvarez, Blanca Beatriz; Delfino, Giovanni; Nosi, Daniele; Terreni, Alessandro

2005-02-01

Serous (poison) cutaneous glands of the leptodactylid species Physalaemus albonotatus and Leptodactylus chaquensis were compared using light and transmission electron microscopy. Glands in the two species share structural traits common in anurans, including the peripheral contractile sheath (myoepithelium) and the syncytial secretory unit that produces, stores, and modifies the poison. At the ultrastructural level, early steps of poison production are also similar and fit the usual path of proteosynthesis, involving rough endoplasmic reticulum (RER) and Golgi stacks (dictyosomes) in the peripheral syncytial cytoplasm. However, several differences are obvious during the maturational processes that lead post-Golgian products to their ultimate ultrastructural traits. In P. albonotatus, the dense product released from the dictyosomes acquires a thick repeating substructure, which, however, becomes looser in the inner portion of the syncytium. In L. chaquensis, serous maturation involves gradual condensation, and opaque, somewhat "vacuolized" granules are formed. These different maturational paths expressed during poison manufacturing in the two species agree with the polyphyletic origin of the family Leptodactylidae. On the other hand, data collected for P. albonotatus fit previous findings from P. biligonigerus and stress the view that poisons produced by congeneric species share similar (or identical) ultrastructural features. Copyright 2004 Wiley-Liss, Inc.

Ultrastructural changes of sheep cumulus-oocyte complexes following different methods of vitrification.

PubMed

Ebrahimi, Bita; Valojerdi, Mojtaba Rezazadeh; Eftekhari-Yazdi, Poopak; Baharvand, Hossein

2012-05-01

To determine the ultrastructural changes of sheep cumulus-oocyte complexes (COCs) following different methods of vitrification, good quality isolated COCs (GV stage) were randomly divided into the non-vitrified control, conventional straw, cryotop and solid surface vitrification groups. In both conventional and cryotop methods, vitrified COCs were respectively loaded by conventional straws and cryotops, and then plunged directly into liquid nitrogen (LN2); whereas in the solid surface group, vitrified COCs were first loaded by cryotops and then cooled before plunging into LN2. Post-warming survivability and ultrastructural changes of healthy COCs in the cryotop group especially in comparison with the conventional group revealed better viability rate and good preservation of the ooplasm organization. However in all vitrification groups except the cryotop group, mitochondria were clumped. Solely in the conventional straw group, the mitochondria showed different densities and were extremely distended. Moreover in the latter group, plenty of large irregular connected vesicles in the ooplasm were observed and in some parts their membrane ruptured. Also, in the conventional and solid surface vitrification groups, cumulus cells projections became retracted from the zona pellucida in some parts. In conclusion, the cryotop vitrification method as compared with other methods seems to have a good post-warming survivability and shows less deleterious effects on the ultrastructure of healthy vitrified-warmed sheep COCs.

Efficacy of a New Ocular Surface Modulator in Restoring Epithelial Changes in an In Vitro Model of Dry Eye Syndrome.

PubMed

Barabino, Stefano; De Servi, Barbara; Aragona, Salvatore; Manenti, Demetrio; Meloni, Marisa

2017-03-01

So far tear substitutes have demonstrated a limited role in restoring ocular surface damage in dry eye syndrome (DES). The aim of this study was to assess the efficacy of a new ocular surface modulator in an in vitro model of human corneal epithelium (HCE) damaged by severe osmotic stress mirroring the features of dry eye conditions. A reconstructed HCE model challenged by the introduction of sorbitol in the culture medium for 16 h was used to induce an inflammatory pathway and to impair the tight junctions integrity determining a severe modification of the superficial layer ultrastructure. At the end of the overnight stress period in the treated HCE series, 30 μl of the ocular surface modulator (T-LysYal, Sildeha, Switzerland) and of hyaluronic acid (HA) in the control HCE series were applied for 24 h. The following parameters were quantified: scanning electron microscopy (SEM), trans-epithelial electrical resistance (TEER), immunofluorescence analysis of integrin β1 (ITG-β1), mRNA expression of Cyclin D-1 (CCND1), and ITG-β1. In the positive control after the osmotic stress the HCE surface damage was visible at the ultrastructural level with loss of cell-cell interconnections, intercellular matrix destruction, and TEER reduction. After 24 h of treatment with T-LysYal, HCE showed a significant improvement of the ultrastructural morphological organization and increased expression of ITG-β1 at the tissue level when compared to positive and control series. A significant increase of mRNA expression for ITG-β1 and CCND1 was shown in the HA-treated cells compared to T-LysYal. TEER measurement showed a significant reduction in all groups after 16 h without modifications after the treatment period. This study has shown the possibility of a new class of agents denominated ocular surface modulators to restore corneal cells damaged by dry eye conditions. Further in vivo studies are certainly necessary to confirm these results.

Acute toxicity of commercial atrazine in Piaractus mesopotamicus: Histopathological, ultrastructural, molecular, and genotoxic evaluation

PubMed Central

de Paiva, Paula Pereira; Delcorso, Mariana Cruz; Matheus, Valquíria Aparecida; de Queiroz, Sonia Claudia do Nascimento; Collares-Buzato, Carla Beatriz; Arana, Sarah

2017-01-01

Aim: The aim of this work was to evaluate the sensitivity of Pacu fingerlings (Piaractus mesopotamicus) by measuring the effects of median lethal concentration (LC50) of atrazine (ATZ - 28.58 mg/L) after acute exposure (up to 96 h). Materials and Methods: The fish were exposed to the LC50 of ATZ for 96 h (28.58 mg/L) in a static system. During the experiment, the fingerlings were randomly distributed in four glass tanks (50 L) containing dechlorinated water. Four glass tanks were for the control group, and four were for the ATZ-exposed group (n=4 per glass tank), given a total number of 16 animals tested per group. The genotoxicity was evaluated by micronucleus (MN) test in erythrocytes from peripheral blood. Qualitative and semi-quantitative histopathological analyses, and also ultrastructural study, were applied in liver and kidney samples. Finally, the content of heat shock protein (Hsp70) in the liver was evaluated by the western blotting method. Results: The morphological alterations in the liver, which was associated with increased expression of Hsp70, included nuclear and cytoplasmic vacuolization, cytoplasmic hyaline inclusions, and necrosis. The kidney presented edema and tubular cell degeneration with cytoplasmic hyaline inclusion. The semi-quantitative histopathological analyses indicated that the liver was more sensitive than kidney to ATZ-induced damage. Ultrastructural analysis showed that ATZ caused membrane alterations in several organelles and increased the number of lysosomes in hepatocytes and kidney proximal tubular cells. Nevertheless, no significant difference was observed in MN frequency in erythrocytes comparing treated and control groups., Conclusion: These results indicated that ATZ-induced damage to the kidney and liver function, ATZ at the concentration tested did not induce a significant difference in MN frequency in Pacu erythrocytes comparing treated and control groups, and also that Pacu fingerlings may be a good bioindicator for testing freshwater contamination. PMID:29062187

Yining Zeng | NREL

Science.gov Websites

pretreatment conditions and biological digestion methods, which might not be detected by large-scale ) "Coherent Raman Microscopy Analysis of Plant Cell Walls," Biomass Conversion: Methods and Protocols, Methods in Molecular Biology (2012) "Chemical, Ultrastructural and Supramolecular Analysis

Membrane alterations induced by nonstructural proteins of human norovirus

PubMed Central

White, Peter A.; Hansman, Grant S.

2017-01-01

Human noroviruses (huNoV) are the most frequent cause of non-bacterial acute gastroenteritis worldwide, particularly genogroup II genotype 4 (GII.4) variants. The viral nonstructural (NS) proteins encoded by the ORF1 polyprotein induce vesical clusters harboring the viral replication sites. Little is known so far about the ultrastructure of these replication organelles or the contribution of individual NS proteins to their biogenesis. We compared the ultrastructural changes induced by expression of norovirus ORF1 polyproteins with those induced upon infection with murine norovirus (MNV). Characteristic membrane alterations induced by ORF1 expression resembled those found in MNV infected cells, consisting of vesicle accumulations likely built from the endoplasmic reticulum (ER) which included single membrane vesicles (SMVs), double membrane vesicles (DMVs) and multi membrane vesicles (MMVs). In-depth analysis using electron tomography suggested that MMVs originate through the enwrapping of SMVs with tubular structures similar to mechanisms reported for picornaviruses. Expression of GII.4 NS1-2, NS3 and NS4 fused to GFP revealed distinct membrane alterations when analyzed by correlative light and electron microscopy. Expression of NS1-2 induced proliferation of smooth ER membranes forming long tubular structures that were affected by mutations in the active center of the putative NS1-2 hydrolase domain. NS3 was associated with ER membranes around lipid droplets (LDs) and induced the formation of convoluted membranes, which were even more pronounced in case of NS4. Interestingly, NS4 was the only GII.4 protein capable of inducing SMV and DMV formation when expressed individually. Our work provides the first ultrastructural analysis of norovirus GII.4 induced vesicle clusters and suggests that their morphology and biogenesis is most similar to picornaviruses. We further identified NS4 as a key factor in the formation of membrane alterations of huNoV and provide models of the putative membrane topologies of NS1-2, NS3 and NS4 to guide future studies. PMID:29077760

Ultrastructural and mechanical changes in tubular epithelial cells by angiotensin II and aldosterone as observed with atomic force microscopy.

PubMed

Quan, Fu-Shi; Jeong, Kyung Hwan; Lee, Gi-Ja

2018-07-01

Tubular epithelial cells (TECs) play an important pathophysiological role in the promotion of renal fibrosis. Quantitative analysis of the mechanical changes in TECs may be helpful in evaluating novel pharmacological strategies. Atomic force microscopy (AFM) is a common nanotechnology tool used for imaging and measuring interaction forces in biological systems. In this study, we used AFM to study ultrastructural and mechanical changes in TECs mediated by the renin-angiotensin-aldosterone system. We quantitatively analyzed changes in the mechanical properties of TECs using three extrinsic factors, namely, chemical fixation, angiotensin II (AT II), and aldosterone (AD). Fixed TECs were 11 times stiffer at the cell body and 3 times stiffer at the cell-cell junction compared to live TECs. After stimulation with AT II, live TECs were four times stiffer at the junctional area than at the cell body, while fixed TECs after AT II stimulation were approximately two times stiffer at the both cell body and cell-cell junction compared to fixed unstimulated TECs. Fixed TECs also reflected changes in the mechanical properties of TECs at the cell body region after AD stimulation. Together, our results suggest that cell stiffness at the cell body region may serve as an effective index for evaluating drugs and stimulation, regardless of whether the cells are live or fixed at the time of analysis. In addition, studying the changes to the intrinsic mechanical property of TECs after application of external stimuli may be useful for investigating pathophysiologic mechanisms and effective therapeutic strategies for renal injury. Copyright © 2018 Elsevier Ltd. All rights reserved.

Inclusion dynamics in PC12 is comparable between amphetamines and MPTP.

PubMed

Gesi, Marco; Lazzeri, Gloria; Ferrucci, Michela; Pellegrini, Antonio; Lenzi, Paola; Ruggieri, Stefano; Fornai, Francesco; Paparelli, Antonio

2006-08-01

In previous studies it was demonstrated that amphetamine derivatives and 1-methyl article-4-phenylpyridinium produce neuronal cell bodies. In the present work, we compared the fine ultrastructure of the intracellular inclusions induced by these different neurotoxic treatments. In particular, we compared the dynamical changes occurring when a mild toxic stimulus acts for different time intervals. For this purpose, we exposed catecholamine-synthesizing PC12 cells to different amphetamine derivatives (methamphetamine and 3,4-methylenedioxymethamphetamine), or 1-methyl-4-phenylpyridinium ion, which represents the active metabolite of the neurotoxin 1-methyl-4-phenyl-1,3,4,6-tetrahydropyridine. Despite inclusions that are elicited by different mechanisms depending on the specific neurotoxin, their ultrastructural features are similar and there is a high parallelism in their temporal evolution. This suggests that formation of inclusions is a multi-step process that might be elicited by different stimuli and, once triggered, leads to the same final effect.

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

PubMed

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.

Three-dimensional ultrastructure of the surface of the tongue of the rat snake, Elaphe climacophora.

PubMed

Iwasaki, S; Yoshizawa, H; Kawahara, I

1996-05-01

Many studies have been performed to clarify the relationship between behavioral performance of the tongue and Jacobson's organ. The purpose of the present study was to examine the ultrastructural features of the surface of the tongue of the rat snake, Elaphe climacophora, and to delineate the functional relationship between the tongue and Jacobson's organ from a morphological perspective. The three-dimensional ultrastructure of the surface of the tongue of the rat snake Elaphe climacophora was investigated by scanning electron microscopy. Most of the surface of the bifurcated apex of the tongue was relatively smooth. Dome-shaped, hemispherical bulges or microfacets were compactly arranged on the epithelial cell surface over this entire region. Intercellular borders were clearly recognizable as striations. These features were almost the same as those of the dorsal surface of the transitional area between the bifurcated lingual apex and the anterior part of the lingual body. In the posterior half of the lingual body, no microfacets were seen at all. Both microridges and microvilli were compactly distributed on cell surfaces. No evidence was obtained from our ultrastructural analysis for an important role of the lingual apex in the vomeronasal system. By contrast, the epithelial surface of the body of the tongue appeared suitable for retaining stimulating compounds.

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

PubMed

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.

Pigmented Cells in the Pineal Gland of Female Viscacha (Lagostomus maximus maximus): A Histochemical and Ultrastructural Study

PubMed Central

Busolini, Fabricio Ivan; Rodríguez, Graciela Beatriz; Filippa, Verónica Palmira

2017-01-01

The presence of pigment has been demonstrated in different nervous structures such as those of retina, substantia nigra, and locus coeruleus. These pigments have also been described in the pineal gland of different mammal species. Histochemical and ultrastructural studies of the pineal gland of female viscacha (Lagostomus maximus maximus) were performed to analyze the presence of pigmented cells under natural conditions and to evaluate a probable relation between pigment content and glandular activity during pregnancy. The following techniques were applied: hematoxylin-eosin, phosphotungstic acid-hematoxylin, Masson-Fontana silver, DOPA histochemistry, Schmorl's reaction and toluidine blue. Estradiol and progesterone serum levels were determined by RIA. The ultrastructural features of the pineal pigment granules were also analyzed. Pigment granules were observed in a random distribution, but the pigmented cells were frequently found near blood vessels. The pineal pigment was histochemically identified as melanin. Differences in the amount of pigmented cells were found between pregnant and nonpregnant viscachas. The ultrastructural analysis revealed the presence of premelanosomes and melanosomes. Estradiol and progesterone levels vary during pregnancy. In conclusion, the changes in the amount of pigment content and hormone levels may indicate that the pineal gland of female viscacha is susceptible to endocrine variations during pregnancy. PMID:29391866

Large-scale tissue clearing (PACT): Technical evaluation and new perspectives in immunofluorescence, histology, and ultrastructure.

PubMed

Neckel, Peter H; Mattheus, Ulrich; Hirt, Bernhard; Just, Lothar; Mack, Andreas F

2016-09-29

Novel techniques, like CLARITY and PACT, render large tissue specimens transparent and thereby suitable for microscopic analysis. We used these techniques to evaluate their potential in the intestine as an exemplary organ with a complex tissue composition. Immunohistochemistry, light sheet-, and confocal scanning-microscopy enabled us to follow complex three-dimensional structures, like nerve fibers, vessels, and epithelial barriers throughout the entire organ. Moreover, in a systematic electron microscopic study, we analyzed the morphology and preservation of tissue on ultrastructural level during the clearing process. We also connect tissue clearing with classical histology and demonstrate that cleared tissues can be stained with Hematoxylin-Eosin and Heidenhain's Azan stain, suggesting potential use in histopathology. These experiments showed that a neutral pH during the clearing process results in much better preservation of tissue ultrastructure and standard stainability. Volume changes of specimens were monitored and quantified during the course of the protocol. Additionally, we employed the technique to visualize the enteric nervous system and the epithelial barrier in post mortem human gut preparations. Our data show the high potential of tissue clearing throughout different tissue types supporting its usefulness in research and diagnosis, and contribute to the technical discussion of ultrastructural tissue-retention.

Large-scale tissue clearing (PACT): Technical evaluation and new perspectives in immunofluorescence, histology, and ultrastructure

PubMed Central

Neckel, Peter H.; Mattheus, Ulrich; Hirt, Bernhard; Just, Lothar; Mack, Andreas F.

2016-01-01

Novel techniques, like CLARITY and PACT, render large tissue specimens transparent and thereby suitable for microscopic analysis. We used these techniques to evaluate their potential in the intestine as an exemplary organ with a complex tissue composition. Immunohistochemistry, light sheet-, and confocal scanning-microscopy enabled us to follow complex three-dimensional structures, like nerve fibers, vessels, and epithelial barriers throughout the entire organ. Moreover, in a systematic electron microscopic study, we analyzed the morphology and preservation of tissue on ultrastructural level during the clearing process. We also connect tissue clearing with classical histology and demonstrate that cleared tissues can be stained with Hematoxylin-Eosin and Heidenhain’s Azan stain, suggesting potential use in histopathology. These experiments showed that a neutral pH during the clearing process results in much better preservation of tissue ultrastructure and standard stainability. Volume changes of specimens were monitored and quantified during the course of the protocol. Additionally, we employed the technique to visualize the enteric nervous system and the epithelial barrier in post mortem human gut preparations. Our data show the high potential of tissue clearing throughout different tissue types supporting its usefulness in research and diagnosis, and contribute to the technical discussion of ultrastructural tissue-retention. PMID:27680942

Microstructural and ultrastructural assessment of inferior alveolar nerve damage following nerve lateralization and implant placement: an experimental study in rabbits.

PubMed

Yoshimoto, Marcelo; Watanabe, Il-sei; Martins, Marília T; Salles, Marcos B; Ten Eyck, Gary R; Coelho, Paulo G

2009-01-01

The present study assessed damage to the inferior alveolar nerve (IAN) following nerve lateralization and implant placement surgery through optical and transmission electron microscopy (TEM). IAN lateralization was performed in 16 adult female rabbits (Oryctolagus cuniculus). During the nerve lateralization procedure, one implant was placed through the mandibular canal, and the IAN was replaced in direct contact with the implant. The implant was placed in the right mandible, and the left side was used as a control (no surgical procedure). After 8 weeks, the animals were sacrificed and samples were prepared for optical and TEM analysis of IAN structural damage. Histomorphometric analysis was performed to determine the number and cross-sectional dimensions of nerve fascicles and myelin sheath thickness between experimental and control groups. The different parameters were compared by one-way analysis of variance at the 95% significance level. Alterations in the perineural and endoneural regions of the IAN, with higher degrees of vascularization, were observed in the experimental group. TEM showed that the majority of the myelinated nerve fibers were not affected in the experimental samples. No significant variation in the number of fascicles was observed, significantly larger fascicle height and width were observed in the control group, and significantly thicker myelin sheaths were observed in the experimental samples. IAN lateralization resulted in substantial degrees of tissue disorganization at the microstructural level because of the presence of edema. However, at the ultrastructural level, small amounts of fiber degeneration were observed.

[Ultrastructure of nephridial systems in cyclophyllidean cestoda: Catenotaenia pusilla (Goeze, 1782), Hymenolepis diminuta (Rudolphi, 1819) and Inermicapsifer madagascariensis (Davaine, 1870) Baer, 1956].

PubMed

Swiderski, Z; Euzet, L; Schönenberger, N

1975-01-01

Electron microscopic study of nephridial systems in three cyclophyllidean cestodes indicates a resemblance in their ultrastructure. The walls of longitudinal, transverse and collecting ducts show a very similar pattern of organization. The surface of the anucleate epithelium lining the ducts is developed into microvilli. A relatively thick layer of fibrillar tissue underlies the basal membrane of the microvillar epithelium. The nucleated portions or "pericaryons", situated between the parenchymal cells, are directly connected with epithelium by cytoplasmic prolongations. The canalicular lumen extends through a single series of cells curved into a ring. The epithelial surface of the canalicular wall is developed into short, densly staining microvilli and the immediately underlying fibrillar tissue appears very compact. The cilia were never observed in any of the above ducts. The ultrastructure of protonephridia proper is comparable with those already described in other cestodes. There is a close association between the flame-cell and the cancalicular ending, enlarged into a nephridial funnel. A single row of nephridial rods of the flame-cell is surrounded by a row of digitiform prolongations of the nephridial funnel border. The prolongations alternate with the rods and their interlocking pattern appears clearly in cross-sections. A series of minute pores or "nephrostomes" providing a direct contact between the nephridial chamber and intercellular space of the paranchyma was shown. The problem of classification and definition between the "closed" protonephridia and open metanephridia is discussed. The structural unity of protonephridia in different groupes of Platyhelminthes is reviewed. The different number of flagella within the "flames" of different cestodes is compared and analyzed. The ultrastructural characteristics of duct-wall epithelium provides some confirmation of its high metabolic activity.

Effects of estrogen replacement therapy on the myelin sheath ultrastructure of myelinated fibers in the white matter of middle-aged ovariectomized rats.

PubMed

He, Qi; Luo, Yanmin; Lv, Fulin; Xiao, Qian; Chao, Fenglei; Qiu, Xuan; Zhang, Lei; Gao, Yuan; Xiu, Yun; Huang, Chunxia; Tang, Yong

2018-04-01

The effects of estrogen replacement therapy (ORT) on white matter and the myelin sheath ultrastructure in the white matter of middle-aged ovariectomized (OVX) rats were investigated in this study. Middle-aged rats were ovariectomized and divided into a placebo replacement (OVX + O) group and an estrogen replacement (OVX + E) group. Then, the Morris water maze, electron microscope techniques, and stereological methods were used to investigate the effects of ORT on spatial learning capacity, white matter volume and the myelin sheath ultrastructure in the white matter. We found that the spatial learning capacity of the OVX + E rats was significantly improved compared with that of the OVX + O rats. When compared with that of OVX + O rats, the total volume of the myelin sheaths in the white matter of the OVX + E rats was significantly increased by 27%, and the difference between the outer perimeter and inner perimeter of the myelin sheaths of the white matter in the OVX + E rats increased significantly by 12.6%. The myelinated fibers with mean diameters of 1.2-1.4 μm were significantly longer (46.1%) in the OVX + E rats; the difference between the mean diameter of myelinated fibers and the mean diameter of axons (0-0.4 μm) was significantly increased by 21.6% in the OVX + E rats. These results suggested that ORT had positive protective effects on the spatial learning ability and on the myelin sheath ultrastructure in the white matter of middle-aged OVX rats. © 2017 Wiley Periodicals, Inc.

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

PubMed

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.

Effects of Chinese herbal medicine Yinsiwei compound on spatial learning and memory ability and the ultrastructure of hippocampal neurons in a rat model of sporadic Alzheimer disease.

PubMed

Diwu, Yong-chang; Tian, Jin-zhou; Shi, Jing

2011-02-01

To study the effects of Chinese herbal medicine Yinsiwei compound (YSW) on spatial learning and memory ability in rats with sporadic Alzheimer disease (SAD) and the ultrastructural basis of the hippocampal neurons. A rat model of SAD was established by intracerebroventricular injection of streptozotocin. The rats were divided into six groups: sham-operation group, model group, donepezil control group, and YSW low, medium and high dose groups. Drug interventions were started on the 21st day after modeling and each treatment group was given the corresponding drugs by gavage for two months. Meanwhile, the model group and the sham-operation group were given the same volume of distilled water by gavage once a day for two months. The Morris water maze was adopted to test spatial learning and memory ability of the rats. The place navigation test and the spatial probe test were conducted. The escape latency, total swimming distance and swimming time in the target quadrant of the rats were recorded. Also, the hippocampus tissues of rats were taken out and the ultrastructure of hippocampus neurons were observed by an electron microscope. In the place navigation test, compared with the model group, the mean escape latency and the total swimming distance of the donepezil group and the YSW low, medium and high dose groups were significantly shortened (P<0.05 or P<0.01). In the space probe test, the swimming time of each treatment group in the target quadrant was significantly longer than that of the model group (P<0.05 or P<0.01). For most of the test period, the donepezil group had no significant change compared with the YSW low, medium and high dose groups, respectively. The ultrastructure of the hippocampus neurons under the electron microscope also confirmed the efficacy of the drug treatment. Chinese herbal medicine YSW compound can improve spatial learning and memory impairment of rats with SAD. The ultrastructural basis may be that it can protect the microtubule structures of hippocampal neurons and prevent nerve axons from being damaged.

The effect of different concentrations of copper and lead on the morphology and physiology of Hypnea musciformis cultivated in vitro: a comparative analysis.

PubMed

Santos, Rodrigo W; Schmidt, Éder C; Vieira, Izabela C; Costa, Giulia B; Rover, Ticiane; Simioni, Carmen; Barufi, José Bonomi; Soares, Carlos Henrique L; Bouzon, Zenilda L

2015-09-01

Copper and lead, as remnants of industrial activities and urban effluents, have heavily contaminated many aquatic environments. Therefore, this study aimed to determine their effects on the physiological, biochemical, and cell organization responses of Hypnea musciformis under laboratory conditions during a 7-day experimental period. To accomplish this, segments of H. musciformis were exposed to photosynthetic active radiation at 80 μmol photons m(-2) s(-1), Cu (0.05 and 0.1 mg kg(-1)), and Pb (3.5 and 7 mg kg(-1)). Various intracellular abnormalities resulted from exposure to Cu and Pb, including a decrease in phycobiliproteins. Moreover, carotenoid and flavonoid contents, as well as phenolic compounds, were decreased, an apparent reflection of chemical antioxidant defense against reactive oxygen species. Treatment with Cu and Pb also caused an increase in the number of floridean starch grains, probably as a defense against nutrient deprivation. Compared to plants treated with lead, those treated with copper showed higher metabolic and ultrastructural alterations. These results suggest that H. musciformis more readily internalizes copper through transcellular absorption. Finally, as a result of ultrastructural damage and metabolic changes observed in plants exposed to different concentrations of Cu and Pb, a significant reduction in growth rates was observed. Nevertheless, the results indicated different susceptibility of H. musciformis to different concentrations of Cu and Pb.

Comparative analysis of Beggiatoa from hypersaline and marine environments.

PubMed

de Albuquerque, Julia Peixoto; Keim, Carolina Neumann; Lins, Ulysses

2010-07-01

The main criterion to classify a microorganism as belonging to the genus Beggiatoa is its morphology. All multicellular, colorless, gliding bacterial filaments containing sulfur globules described so far belong to this genus. At the ultrastructural level, they show also a very complex cell envelope structure. Here we describe uncultured vacuolated and non-vacuolated bacteria from two different environments showing all characteristics necessary to assign a bacterium to the genus Beggiatoa. We also intended to investigate whether narrow and vacuolate Beggiatoa do differ morphologically as much as they do phylogenetically. Both large, vacuolated trichomes and narrow filaments devoid of vacuoles were observed. We confirmed the identity of the narrow filaments by 16S rRNA phylogenetic analysis. The diameters of the trichomes ranged from 2.4 to 34 microm, and their lengths ranged from 10 microm to over 30 mm. Narrow trichomes moved by gliding at 3.0 microm/s; large filaments moved at 1.5 microm/s. Periplasmic sulfur inclusions were observed in both types of filaments, whereas phosphorus-rich bodies were found only in narrow trichomes. On the other hand, nitrate vacuoles were observed only in large trichomes. Ultra-thin section transmission electron microscopy showed differences between the cell ultrastructure of narrow (non-vacuolated) and large (vacuolated) Beggiatoa. We observed that cell envelopes from narrow Beggiatoa consist of five layers, whereas cell envelopes from large trichomes contain four layers. Copyright 2010 Elsevier Ltd. All rights reserved.

Nucleolar cycle and chromatoid body formation: is there a relationship between these two processes during spermatogenesis of Dendropsophus minutus (Amphibia, Anura)?

PubMed

Peruquetti, Rita Luiza; Taboga, Sebastião Roberto; Santos, Lia Raquel de Souza; Oliveira, Classius de; Azeredo-Oliveira, Maria Tercília Vilela de

2011-01-01

The goals of this study were to monitor the nucleolar material distribution during Dendropsophus minutus spermatogenesis using cytological and cytochemical techniques and ultrastructural analysis, as well as to compare the nucleolar material distribution to the formation of the chromatoid body (CB) in the germ epithelium of this amphibian species. Nucleolar fragmentation occurred during the pachytene of prophase I and nucleolus reorganization occurred in the early spermatid nucleus. The area of the spermatogonia nucleolus was significantly larger than that of the earlier spermatid nucleolus. Ultrastructural analysis showed an accumulation of nuages in the spermatogonia cytoplasm, which form the CB before nucleolar fragmentation. The CB was observed in association with mitochondrial clusters in the cytoplasm of primary spermatocytes, as well as in those of earlier spermatids. In conclusion, the nucleolus seems to be related to CB formation during spermatogenesis of D. minutus, because, at the moment of nucleolus fragmentation in the primary spermatocytes, the CB area reaches a considerable size and is able to execute its important functions during spermatogenesis. The reorganized nucleolus of the earlier spermatids has a smaller area due to several factors, among them the probable migration of nucleolar fragments from the nucleus to the cytoplasm, and plays a part in the CB chemical composition. Copyright © 2010 Elsevier Ltd. All rights reserved.

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

PubMed

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

2015-06-01

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. Copyright © 2015 Elsevier Ltd. All rights reserved.

Clinical Features of Childhood Primary Ciliary Dyskinesia by Genotype and Ultrastructural Phenotype

PubMed Central

Ferkol, Thomas W.; Rosenfeld, Margaret; Lee, Hye-Seung; Dell, Sharon D.; Sagel, Scott D.; Milla, Carlos; Zariwala, Maimoona A.; Pittman, Jessica E.; Shapiro, Adam J.; Carson, Johnny L.; Krischer, Jeffrey P.; Hazucha, Milan J.; Cooper, Matthew L.; Knowles, Michael R.; Leigh, Margaret W.

2015-01-01

Rationale: The relationship between clinical phenotype of childhood primary ciliary dyskinesia (PCD) and ultrastructural defects and genotype is poorly defined. Objectives: To delineate clinical features of childhood PCD and their associations with ultrastructural defects and genotype. Methods: A total of 118 participants younger than 19 years old with PCD were evaluated prospectively at six centers in North America using standardized procedures for diagnostic testing, spirometry, chest computed tomography, respiratory cultures, and clinical phenotyping. Measurements and Main Results: Clinical features included neonatal respiratory distress (82%), chronic cough (99%), and chronic nasal congestion (97%). There were no differences in clinical features or respiratory pathogens in subjects with outer dynein arm (ODA) defects (ODA alone; n = 54) and ODA plus inner dynein arm (IDA) defects (ODA + IDA; n = 18) versus subjects with IDA and central apparatus defects with microtubular disorganization (IDA/CA/MTD; n = 40). Median FEV1 was worse in the IDA/CA/MTD group (72% predicted) versus the combined ODA groups (92% predicted; P = 0.003). Median body mass index was lower in the IDA/CA/MTD group (46th percentile) versus the ODA groups (70th percentile; P = 0.003). For all 118 subjects, median number of lobes with bronchiectasis was three and alveolar consolidation was two. However, the 5- to 11-year-old IDA/CA/MTD group had more lobes of bronchiectasis (median, 5; P = 0.0008) and consolidation (median, 3; P = 0.0001) compared with the ODA groups (median, 3 and 2, respectively). Similar findings were observed when limited to participants with biallelic mutations. Conclusions: Lung disease was heterogeneous across all ultrastructural and genotype groups, but worse in those with IDA/CA/MTD ultrastructural defects, most of whom had biallelic mutations in CCDC39 or CCDC40. PMID:25493340

In Vivo Effect of Calcium Hydroxide and Resin-modified Glass Ionomer Cement on Carious Dentin in Young Permanent Molars: An Ultrastructural and Macroscopic Study.

PubMed

Opal, Shireen; Garg, Shalini; Sharma, Deepak; Dhindsa, Abhishek; Jatana, Isha

2017-01-15

The purpose of this study was to evaluate macroscopically and ultrastructurally the effect of calcium hydroxide cement (CH) and resin-modified glass ionomer cement (RMGIC) compared with gutta percha (control) as a lining material on carious dentin after partial caries removal and sealing. Twenty-seven permanent molars with deep carious lesions underwent partial caries removal with the application of CH, RMGIC, or gutta percha (control) and were then sealed for three months. After a partial caries removal and sealing period, the dentin was macroscopically assessed (for color, consistency, and humidity) and further analyzed by scanning electron microscope to assess the ultrastructural changes in dentin (lumen size, mineralization of tubules, occlusion of tubules by cements, and bacterial ingress). The effect of treatment in each group was statistically analyzed. Dentin darkening and hardening were observed after the sealing period in all groups. However, there was no difference in the color after treatment among the three groups. It was observed that RMGIC showed a significant reduction in the size of the lumen compared to CH and the control. Partial caries removal and sealing resulted in dentin hardening, darkening, and dentin remineralization, irrespective of the dentin protection used.

Iris ultrastructure in patients with synechiae as revealed by in vivo laser scanning confocal microscopy : In vivo iris ultrastructure in patients with Synechiae by Laser Scanning Confocal Microscopy.

PubMed

Li, Ming; Cheng, Hongbo; Guo, Ping; Zhang, Chun; Tang, Song; Wang, Shusheng

2016-04-26

Iris plays important roles in ocular physiology and disease pathogenesis. Currently it is technically challenging to noninvasively examine the human iris ultrastructure in vivo. The purpose of the current study is to reveal human iris ultrastructure in patients with synechiae by using noninvasive in vivo laser scanning confocal microscopy (LSCM). The ultrastructure of iris in thirty one patients, each with synechiae but transparent cornea, was examined by in vivo LSCM. Five characteristic iris ultrastructures was revealed in patients with synechiae by in vivo LSCM, which include: 1. tree trunk-like structure; 2. tree branch/bush-like structure; 3. Fruit-like structure; 4. Epithelioid-like structure; 5. deep structure. Pigment granules can be observed as a loose structure on the top of the arborization structure. In iris-associated diseases with Tyndall's Phenomenon and keratic precipitates, the pigment particles are more likely to fall off from the arborization structure. The ultrastructure of iris in patients with synechiae has been visualized using in vivo LSCM. Five iris ultrastructures can be clearly observed, with some of the structures maybe disease-associated. The fall-off of the pigment particles may cause the Tyndall's Phenomenon positive. In vivo LSCM provides a non-invasive approach to observe the human iris ultrastructure under certain eye disease conditions, which sets up a foundation to visualize certain iris-associated diseases in the future.

Photosynthetic and ultrastructural responses of Ulva australis to Zn stress.

PubMed

Farias, D R; Schmidt, E; Simioni, C; Bouzon, Z L; Hurd, C L; Eriksen, R S; Macleod, C K

2017-12-01

This research evaluated the effect of zinc (Zn) on the ultrastructure and the photosynthetic efficiency of a common green alga. Ulva australis was grown in the laboratory for 7days under a range of different Zn concentrations (0, 25, 50 and 100μgL -1 ). Growth rate (Gr), photosynthetic efficiency (Fv/Fm and ETRmax), photosynthetic pigments, and metal accumulation were measured. Samples of 1mm length were taken to analyse the effect of Zn on the ultrastructure using transmission electron microscopy (TEM) and cytochemical responses (TB-O and PAS) were evaluated by light microscopy (LM). There were no significant differences in the growth rate, Fv/Fm, ETRmax and the photosynthetic pigments chlorophyll a, chlorophyll b and carotenoids (p>0.05) after 7days of Zn exposure. However, TEM revealed cytoplasm retraction, compression of cellulose fibrils, dissembled thylakoids and electron-dense bodies suggesting ultrastructural impacts from metal exposure and accumulation. Cytological analysis demonstrated that Zn affected U. australis cells at the three concentrations tested. The main effect was cytoplasm retraction and a decrease on the amount of starch granules, following exposure at 25μgL -1 and 50μgL -1 of Zn. We conclude that concentrations of Zn assessed in U. australis in this research has a short-term cellular effect as revealed by TEM and cytological analysis, demonstrating the importance of measuring a broad suite of endpoints to better understand species responses to environmentally relevant concentrations of Zn. However, U. australis was able to physiologically tolerate adverse conditions, since there was no effect on the photosynthetic performance and growth. Copyright © 2017 Elsevier Ltd. All rights reserved.

Implications of obesity for tendon structure, ultrastructure and biochemistry: a study on Zucker rats.

PubMed

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.

Structural and Ultrastructural Alterations in Human Olfactory Pathways and Possible Associations with Herpesvirus 6 Infection

PubMed Central

Skuja, Sandra; Zieda, Anete; Ravina, Kristine; Chapenko, Svetlana; Roga, Silvija; Teteris, Ojars; Groma, Valerija; Murovska, Modra

2017-01-01

Structural and ultrastructural alterations in human olfactory pathways and putative associations with human herpesvirus 6 (HHV-6) infection were studied. The olfactory bulb/tract samples from 20 subjects with an unspecified encephalopathy determined by pathomorphological examination of the brain autopsy, 17 healthy age-matched and 16 younger controls were used. HHV-6 DNA was detected in 60, 29, and 19% of cases in these groups, respectively. In the whole encephalopathy group, significantly more HHV-6 positive neurons and oligodendrocytes were found in the gray matter, whereas, significantly more HHV-6 positive astrocytes, oligodendrocytes, microglia/macrophages and endothelial cells were found in the white matter. Additionally, significantly more HHV-6 positive astrocytes and, in particular, oligodendrocytes were found in the white matter when compared to the gray matter. Furthermore, when only HHV-6 PCR+ encephalopathy cases were studied, we observed similar but stronger associations between HHV-6 positive oligodendrocytes and CD68 positive cells in the white matter. Cellular alterations were additionally evidenced by anti-S100 immunostaining, demonstrating a significantly higher number of S100 positive cells in the gray matter of the whole encephalopathy group when compared to the young controls, and in the white matter when compared to both control groups. In spite the decreased S100 expression in the PCR+ encephalopathy group when compared to PCR- cases and controls, groups demonstrated significantly higher number of S100 positive cells in the white compared to the gray matter. Ultrastructural changes confirming the damage of myelin included irregularity of membranes and ballooning of paranodal loops. This study shows that among the cellular targets of the nervous system, HHV-6 most severely affects oligodendrocytes and the myelin made by them. PMID:28072884

Generation of a three-dimensional ultrastructural model of human respiratory cilia.

PubMed

Burgoyne, Thomas; Dixon, Mellisa; Luther, Pradeep; Hogg, Claire; Shoemark, Amelia

2012-12-01

The ultrastructures of cilia and flagella are highly similar and well conserved through evolution. Consequently, Chlamydomonas is commonly used as a model organism for the study of human respiratory cilia. Since detailed models of Chlamydomonas axonemes were generated using cryoelectron tomography, disparities among some of the ultrastructural features have become apparent when compared with human cilia. Extrapolating information on human disease from the Chlamydomonas model may lead to discrepancies in translational research. This study aimed to establish the first three-dimensional ultrastructural model of human cilia. Tomograms of transverse sections (n = 6) and longitudinal sections (n = 9) of human nasal respiratory cilia were generated from three healthy volunteers. Key features of the cilium were resolved using subatomic averaging, and were measured. For validation of the method, a model of the well characterized structure of Chlamydomonas reinhardtii was simultaneously generated. Data were combined to create a fully quantified three-dimensional reconstruction of human nasal respiratory cilia. We highlight key differences in the axonemal sheath, microtubular doublets, radial spokes, and dynein arms between the two structures. We show a decreased axial periodicity of the radial spokes, inner dynein arms, and central pair protrusions in the human model. We propose that this first human model will provide a basis for research into the function and structure of human respiratory cilia in health and in disease.

Ultrastructural markers of quality are impaired in human metaphase II aged oocytes: a comparison between reproductive and in vitro aging.

PubMed

Bianchi, S; Macchiarelli, G; Micara, G; Linari, A; Boninsegna, C; Aragona, C; Rossi, G; Cecconi, S; Nottola, S A

2015-09-01

Childbearing delay contributes to the increase of subfertile couples that require assisted reproductive technology (ART). Subfertility relates with reproductive aging (RA). In vitro aging (IvA) (due to extended culture) may also impair oocyte competence. Aims of this study were to evaluate and compare the oocyte ultrastructure after RA and IvA. Cumulus-oocyte complexes (COCs) (n = 68), with metaphase II oocyte and expanded cumulus, from consenting patients (<35 years old and ≥35 years old, n = 36), were selected by phase contrast microscopy and fixed at pick up, or after 24 h culture. COCs (n = 44) were studied by light and qualitative/morphometric transmission electron microscopy. Two-way ANOVA, with age and culture as grouping factors, was applied for statistical analysis (p < 0.05). Metaphase II cumulus-free oocytes (n = 24) were selected for confocal microscopy observations. Significant decrease of mitochondria-smooth endoplasmic reticulum aggregates, increase of mitochondria-vesicle complexes size and amount, decrease of cortical granules and microvilli, and alterations of the spindle structure characterized both RA and IvA oocytes. These changes were significantly more evident in the RA oocytes submitted to IvA. RA oocytes also showed changes of the zona pellucida and occurrence of vacuoles after culture. Cumuli appeared re-compacted after culture, irrespective of the age of the patients. These data demonstrated that aging is related to decay of oocyte ultrastructural quality, and that oocytes from elder women are more sensitive to prolonged culture (IvA) than the oocytes from younger women. These morphological results should be considered when applying ART in aged patients, rescue ICSI, or artificial oocyte activation.

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

PubMed

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.

Ultrastructure of spermatozoa of spider crabs, family Mithracidae (Crustacea, Decapoda, Brachyura): Integrative analyses based on morphological and molecular data.

PubMed

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.

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

PubMed Central

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. PMID:26146994

Biodiversity: molecular biological domains, symbiosis and kingdom origins

NASA Technical Reports Server (NTRS)

Margulis, L.

1992-01-01

The number of extant species of organisms is estimated to be from fewer than 3 to more than 30 x 10(6) (May, 1992). Molecular biology, comparative genetics and ultrastructural analyses provide new insights into evolutionary relationships between these species, including increasingly precise ideas of how species and higher taxa have evolved from common ancestors. Accumulation of random mutations and large macromolecular sequence change in all organisms since the Proterozoic Eon has been importantly supplemented by acquisition of inherited genomes ('symbiogenesis'). Karyotypic alterations (polyploidization and karyotypic fissioning) have been added to these other mechanisms of species origin in plants and animals during the Phanerozoic Eon. The new evolution concepts (coupled with current rapid rates of species extinction and ignorance of the extent of biodiversity) prompted this analysis of the field of systematic biology and its role in the reorganization of extant species into higher taxa. Two superkingdoms (= Domains: Prokaryotae and Eukaryotae) and five kingdoms (Monera = Procaryotae or Bacteria; Protoctista: algae, amoebae, ciliates, foraminifera, oomycetes, slime molds, etc.; Mychota: 'true' fungi; Plantae: one phylum (division) of bryophytes and nine phyla of tracheophytes; and Animalia) are recognized. Two subkingdoms comprise the monera: the great diverse lineages are Archaebacteria and Eubacteria. The criteria for classification using molecular, ultrastructural and genetic data for this scheme are mentioned. For the first time since the nineteenth century, logical, technical definitions for each group are given with their time of appearance as inferred from the fossil record in the primary scientific literature. This classification scheme, which most closely reflects the evolutionary history, molecular biology, genetics and ultrastructure of extant life, requires changes in social organization of biologists, many of whom as botanists and zoologists, still behave as if there were only two important kingdoms (plants and animals).

Ultrastructural properties of laser-irradiated and heat-treated dentin.

PubMed

Rohanizadeh, R; LeGeros, R Z; Fan, D; Jean, A; Daculsi, G

1999-12-01

Previous studies using scanning electron microscopy and infrared absorption spectroscopy reported that laser irradiation causes compositional changes in enamel. The purpose of this study was to evaluate the ultrastructural and compositional changes in dentin caused by irradiation with a short-pulse laser (Q-switched Nd:YAG). The irradiated and non-irradiated areas of the lased dentin samples were investigated by scanning (SEM) and transmission electron microscopy (TEM), micro-micro electron diffraction, and electron microprobe analysis of dispersive energy (EDX). Heat-treated dentin was similarly investigated. This study demonstrated that laser irradiation resulted in the recrystallization of dentin apatite and in the formation of additional calcium phosphate phases consisting of magnesium-substituted beta-tricalcium phosphate, beta-TCMP, beta-(Ca,Mg)3(PO4)2, and tetracalcium phosphate, TetCP, Ca4(PO4)O. TEM analyses of the modified and unmodified zones of the irradiated areas showed two types of crystal populations: much larger crystals from the modified zone and crystals with size and morphology similar to those of dentin apatite in the unmodified zone. The morphology of crystals in the modified zones in the irradiated dentin resembled those of dentin sintered at 800 or 950 degrees C. In the irradiated areas (modified and unmodified zones), the Ca/P ratio was lower compared with that in the non-irradiated dentin. The Mg/Ca ratio in the modified zones was higher than that in the unmodified zones and in the non-irradiated dentin. In sintered dentin, the Mg/Ca ratio increased as a function of sintering temperature. The ultrastructural and compositional changes observed in laser-irradiated dentin may be attributed to high temperature and high pressure induced by microplasma during laser irradiation. These changes may alter the solubility of the irradiated dentin, making it less susceptible to acid dissolution or to the caries process.

Ultrastructural and cellular basis for the development of abnormal myocardial mechanics during the transition from hypertension to heart failure.

PubMed

Shah, Sanjiv J; Aistrup, Gary L; Gupta, Deepak K; O'Toole, Matthew J; Nahhas, Amanda F; Schuster, Daniel; Chirayil, Nimi; Bassi, Nikhil; Ramakrishna, Satvik; Beussink, Lauren; Misener, Sol; Kane, Bonnie; Wang, David; Randolph, Blake; Ito, Aiko; Wu, Megan; Akintilo, Lisa; Mongkolrattanothai, Thitipong; Reddy, Mahendra; Kumar, Manvinder; Arora, Rishi; Ng, Jason; Wasserstrom, J Andrew

2014-01-01

Although the development of abnormal myocardial mechanics represents a key step during the transition from hypertension to overt heart failure (HF), the underlying ultrastructural and cellular basis of abnormal myocardial mechanics remains unclear. We therefore investigated how changes in transverse (T)-tubule organization and the resulting altered intracellular Ca(2+) cycling in large cell populations underlie the development of abnormal myocardial mechanics in a model of chronic hypertension. Hearts from spontaneously hypertensive rats (SHRs; n = 72) were studied at different ages and stages of hypertensive heart disease and early HF and were compared with age-matched control (Wistar-Kyoto) rats (n = 34). Echocardiography, including tissue Doppler and speckle-tracking analysis, was performed just before euthanization, after which T-tubule organization and Ca(2+) transients were studied using confocal microscopy. In SHRs, abnormalities in myocardial mechanics occurred early in response to hypertension, before the development of overt systolic dysfunction and HF. Reduced longitudinal, circumferential, and radial strain as well as reduced tissue Doppler early diastolic tissue velocities occurred in concert with T-tubule disorganization and impaired Ca(2+) cycling, all of which preceded the development of cardiac fibrosis. The time to peak of intracellular Ca(2+) transients was slowed due to T-tubule disruption, providing a link between declining cell ultrastructure and abnormal myocardial mechanics. In conclusion, subclinical abnormalities in myocardial mechanics occur early in response to hypertension and coincide with the development of T-tubule disorganization and impaired intracellular Ca(2+) cycling. These changes occur before the development of significant cardiac fibrosis and precede the development of overt cardiac dysfunction and HF.

The Spectrum of Mitochondrial Ultrastructural Defects in Mitochondrial Myopathy

PubMed Central

Vincent, Amy E.; Ng, Yi Shiau; White, Kathryn; Davey, Tracey; Mannella, Carmen; Falkous, Gavin; Feeney, Catherine; Schaefer, Andrew M.; McFarland, Robert; Gorman, Grainne S.; Taylor, Robert W.; Turnbull, Doug M.; Picard, Martin

2016-01-01

Mitochondrial functions are intrinsically linked to their morphology and membrane ultrastructure. Characterizing abnormal mitochondrial structural features may thus provide insight into the underlying pathogenesis of inherited and acquired mitochondrial diseases. Following a systematic literature review on ultrastructural defects in mitochondrial myopathy, we investigated skeletal muscle biopsies from seven subjects with genetically defined mtDNA mutations. Mitochondrial ultrastructure and morphology were characterized using two complimentary approaches: transmission electron microscopy (TEM) and serial block face scanning EM (SBF-SEM) with 3D reconstruction. Six ultrastructural abnormalities were identified including i) paracrystalline inclusions, ii) linearization of cristae and abnormal angular features, iii) concentric layering of cristae membranes, iv) matrix compartmentalization, v) nanotunelling, and vi) donut-shaped mitochondria. In light of recent molecular advances in mitochondrial biology, these findings reveal novel aspects of mitochondrial ultrastructure and morphology in human tissues with implications for understanding the mechanisms linking mitochondrial dysfunction to disease. PMID:27506553

Integrative proteome analysis of Brachypodium distachyon roots and leaves reveals a synergetic responsive network under H2O2 stress.

PubMed

Bian, Yan-Wei; Lv, Dong-Wen; Cheng, Zhi-Wei; Gu, Ai-Qin; Cao, Hui; Yan, Yue-Ming

2015-10-14

The plant oxidative stress response is vital for defense against various abiotic and biotic stresses. In this study, ultrastructural changes and the proteomic response to H2O2 stress in roots and leaves of the model plant Brachypodium distachyon were studied. Transmission electron microscopy (TEM) showed that the ultrastructural damage in roots was more serious than in leaves. Particularly, the ultrastructures of organelles and the nucleus in root tip cells were damaged, leading to the inhibition of normal biological activities of roots, which then spread throughout the plant. Based on two-dimensional electrophoresis (2-DE) and MALDI-TOF/TOF-MS, 84 and 53 differentially accumulated protein (DAP) spots representing 75 and 45 unique proteins responsive to H2O2 stress in roots and leaves, respectively, were identified. These protein species were mainly involved in signal transduction, energy metabolism, redox homeostasis/stress defense, protein folding/degradation, and cell wall/cell structure. Interestingly, two 14-3-3 proteins (GF14-B and GF14-D) were identified as DAPs in both roots and leaves. Protein-protein interaction (PPI) analysis revealed a synergetic H2O2-responsive network. Copyright © 2015 Elsevier B.V. All rights reserved.

A new microsporidian parasite, Potaspora morhaphis n. gen., n. sp. (Microsporidia) infecting the Teleostean fish, Potamorhaphis guianensis from the River Amazon. Morphological, ultrastructural and molecular characterization.

PubMed

Casal, G; Matos, E; Teles-Grilo, M L; Azevedo, C

2008-08-01

A fish-infecting Microsporidia Potaspora morhaphis n. gen., n. sp. found adherent to the wall of the coelomic cavity of the freshwater fish, Potamorhaphis guianensis, from lower Amazon River is described, based on light microscope and ultrastructural characteristics. This microsporidian forms whitish xenomas distinguished by the numerous filiform and anastomosed microvilli. The xenoma was completely filled by several developmental stages. In all of these stages, the nuclei are monokaryotic and develop in direct contact with host cell cytoplasm. The merogonial plasmodium divides by binary fission and the disporoblastic pyriform spores of sporont origin measure 2.8+/-0.3 x 1.5+/-0.2 microm. In mature spores the polar filament was arranged into 9-10 coils in 2 layers. The polaroplast had 2 distinct regions around the manubrium and an electron-dense globule was observed. The small subunit, intergenic space and partial large subunit rRNA gene were sequenced and maximum parsimony analysis placed the microsporidian described here in the clade that includes the genera Kabatana, Microgemma, Spraguea and Tetramicra. The ultrastructural morphology of the xenoma, and the developmental stages including the spores of this microsporidian parasite, as well as the phylogenetic analysis, suggest the erection of a new genus and species.

Effect of lipopeptides of antagonistic strains of Bacillus subtilis on the morphology and ultrastructure of the cucurbit fungal pathogen Podosphaera fusca.

PubMed

Romero, D; de Vicente, A; Olmos, J L; Dávila, J C; Pérez-García, A

2007-10-01

To analyse the morphological and ultrastructural effects of lipopeptides of cell-free liquid cultures from the antagonistic Bacillus subtilis strains, UMAF6614 and UMAF6639, on the cucurbit powdery mildew fungus, Podosphaera fusca, conidial germination. Butanolic extracts from cell-free supernatants of B. subtilis cultures were tested for their ability to arrest P. fusca conidial germination using the zucchini cotyledon disc method. Previously, the occurrence of lipopeptide antibiotics fengycin, iturin/bacillomycin and surfactin in the extracts was verified by diverse chromatographic approaches. Conidial germination was strongly reduced by antifungal extracts obtained from liquid cultures of both B. subtilis strains. Scanning electron microscopy analysis showed morphological damage in conidia characterized by the presence of large depressions and loss of turgidness. Transmission electron microscopy analysis revealed severe modifications in the plasma membrane and disorganization of the P. fusca cell cytoplasm. The lipopeptides produced by the two strains of B. subtilis are able to reduce cucurbit powdery mildew disease by arresting conidial germination, which seems to result from the induction of important cytological alterations. We elucidated the mechanisms employed by these antagonistic strains of B. subtilis to suppress cucurbit powdery mildew disease and delineate the ultrastructural damages responsible for their suppressive effect.

Ultrastructural demonstration of Cx43 gap junctions in induced pluripotent stem cells from human cord blood.

PubMed

Beckmann, Anja; Schubert, Madline; Hainz, Nadine; Haase, Alexandra; Martin, Ulrich; Tschernig, Thomas; Meier, Carola

2016-11-01

Gap junction proteins are essential for direct intercellular communication but also influence cellular differentiation and migration. The expression of various connexin gap junction proteins has been demonstrated in embryonic stem cells, with Cx43 being the most intensely studied. As Cx43 is the most prominent gap junction protein in the heart, cardiomyocyte-differentiated stem cells have been studied intensely. To date, however, little is known about the expression and the subcellular distribution of Cx43 in undifferentiated stem cells or about the structural arrangement of channels. We, therefore, here investigate expression of Cx43 in undifferentiated human cord-blood-derived induced pluripotent stem cells (hCBiPS2). For this purpose, we carried out quantitative real-time PCR and immunohistochemistry. For analysis of Cx43 ultrastructure and protein assembly, we performed freeze-fracture replica immunogold labeling (FRIL). Cx43 expression was detected at mRNA and protein level in hCBIPS2 cells. For the first time, ultrastructural data are presented on gap junction morphology in induced pluripotent stem (iPS) cells from cord blood: Our FRIL and electron microscopical analysis revealed the occurrence of gap junction plaques in undifferentiated iPS cells. In addition, these gap junctions were shown to contain the gap junction protein Cx43.

Clinical Features and Associated Likelihood of Primary Ciliary Dyskinesia in Children and Adolescents

PubMed Central

Ferkol, Thomas W.; Davis, Stephanie D.; Lee, Hye-Seung; Rosenfeld, Margaret; Dell, Sharon D.; Sagel, Scott D.; Milla, Carlos; Olivier, Kenneth N.; Sullivan, Kelli M.; Zariwala, Maimoona A.; Pittman, Jessica E.; Shapiro, Adam J.; Carson, Johnny L.; Krischer, Jeffrey; Hazucha, Milan J.

2016-01-01

Rationale: Primary ciliary dyskinesia (PCD), a genetically heterogeneous, recessive disorder of motile cilia, is associated with distinct clinical features. Diagnostic tests, including ultrastructural analysis of cilia, nasal nitric oxide measurements, and molecular testing for mutations in PCD genes, have inherent limitations. Objectives: To define a statistically valid combination of systematically defined clinical features that strongly associates with PCD in children and adolescents. Methods: Investigators at seven North American sites in the Genetic Disorders of Mucociliary Clearance Consortium prospectively and systematically assessed individuals (aged 0–18 yr) referred due to high suspicion for PCD. The investigators defined specific clinical questions for the clinical report form based on expert opinion. Diagnostic testing was performed using standardized protocols and included nasal nitric oxide measurement, ciliary biopsy for ultrastructural analysis of cilia, and molecular genetic testing for PCD-associated genes. Final diagnoses were assigned as “definite PCD” (hallmark ultrastructural defects and/or two mutations in a PCD-associated gene), “probable/possible PCD” (no ultrastructural defect or genetic diagnosis, but compatible clinical features and nasal nitric oxide level in PCD range), and “other diagnosis or undefined.” Criteria were developed to define early childhood clinical features on the basis of responses to multiple specific queries. Each defined feature was tested by logistic regression. Sensitivity and specificity analyses were conducted to define the most robust set of clinical features associated with PCD. Measurements and Main Results: From 534 participants 18 years of age and younger, 205 were identified as having “definite PCD” (including 164 with two mutations in a PCD-associated gene), 187 were categorized as “other diagnosis or undefined,” and 142 were defined as having “probable/possible PCD.” Participants with “definite PCD” were compared with the “other diagnosis or undefined” group. Four criteria-defined clinical features were statistically predictive of PCD: laterality defect; unexplained neonatal respiratory distress; early-onset, year-round nasal congestion; and early-onset, year-round wet cough (adjusted odds ratios of 7.7, 6.6, 3.4, and 3.1, respectively). The sensitivity and specificity based on the number of criteria-defined clinical features were four features, 0.21 and 0.99, respectively; three features, 0.50 and 0.96, respectively; and two features, 0.80 and 0.72, respectively. Conclusions: Systematically defined early clinical features could help identify children, including infants, likely to have PCD. Clinical trial registered with ClinicalTrials.gov (NCT00323167). PMID:27070726

Ultrastructural analysis of testicular tissue and sperm by transmission and scanning electron microscopy.

PubMed

Chemes, Hector E

2013-01-01

Transmission electron microscopy (TEM) studies have provided the basis for an in-depth understanding of the cell biology and normal functioning of the testis and male gametes and have opened the way to characterize the functional role played by specific organelles in spermatogenesis and sperm function. The development of the scanning electron microscope (SEM) extended these boundaries to the recognition of cell and organ surface features and the architectural array of cells and tissues. The merging of immunocytochemical and histochemical approaches with electron microscopy has completed a series of technical improvements that integrate structural and functional features to provide a broad understanding of cell biology in health and disease. With these advances the detailed study of the intricate structural and molecular organization as well as the chemical composition of cellular organelles is now possible. Immunocytochemistry is used to identify proteins or other components and localize them in specific cells or organelles with high specificity and sensitivity, and histochemistry can be used to understand their function (i.e., enzyme activity). When these techniques are used in conjunction with electron microscopy their resolving power is further increased to subcellular levels. In the present chapter we will describe in detail various ultrastructural techniques that are now available for basic or translational research in reproductive biology and reproductive medicine. These include TEM, ultrastructural immunocytochemistry, ultrastructural histochemistry, and SEM.

Distinctive eosinophilic cytoplasmic inclusion bodies in melanocytic nevi: an immunohistochemical and ultrastructural study.

PubMed

Shon, Wonwoo; Wada, David A; Gibson, Lawrence E; Flotte, Thomas J; Scheithauer, Bernd W

2011-11-01

We sought to further determine the histochemical, immunohistochemical and ultrastructural properties of eosinophilic cytoplasmic inclusion bodies in melanocytic nevi. Skin specimens from four patients with a known diagnosis of conventional melanocytic nevus (3) or Spitz nevus (1) and containing intracytoplasmic eosinophilic inclusion bodies were selected. In addition, melanomas (25), Spitz nevi (10) and blue nevi (4) were examined to determine the frequency of the inclusions. Inclusions tended to be located in multinucleated melanocytes with abundant vacuolated cytoplasm. In conventional (hematoxylin and eosin-stained) sections, the degree of density and eosinophilia of intracytoplasmic inclusions varied with size. Periodic acid-Schiff, Fontana and Congo red stains showed no reactivity. All bodies were immunoreactive for ubiquitin but negative for tyrosinase, keratin and vimentin. Ultrastructurally, inclusion bodies were non-membrane bound, ranged from 4 to 7 µm, and were comprised of radiating filamentous structures with or without an electron-dense core. Electron probe x-ray microanalysis revealed no significant peaks. None of additional melanomas, Spitz nevi and blue nevi that were evaluated showed similar inclusions. The inclusion bodies described herein bear no resemblance to other cytoplasmic inclusion bodies previously described in melanocytic lesions. There is no discernible relationship to melanosomes by ultrastructural analysis. We postulate a relationship with dysfunction of ubiquitin-mediated protein degradation occurring in melanocytes. Copyright © 2011 John Wiley & Sons A/S.

Apoptosis Governs the Elimination of Schistosoma japonicum from the Non-Permissive Host Microtus fortis

PubMed Central

Peng, Jinbiao; Gobert, Geoffrey N.; Hong, Yang; Jiang, Weibin; Han, Hongxiao; McManus, Donald P.; Wang, Xinzhi; Liu, Jinming; Fu, Zhiqiang; Shi, Yaojun; Lin, Jiaojiao

2011-01-01

The reed vole, Microtus fortis, is the only known mammalian host in which schistosomes of Schistosoma japonicum are unable to mature and cause significant pathogenesis. However, little is known about how Schistosoma japonicum maturation (and, therefore, the development of schistosomiasis) is prevented in M. fortis. In the present study, the ultrastructure of 10 days post infection schistosomula from BALB/c mice and M. fortis were first compared using scanning electron microscopy and transmission electron microscopy. Electron microscopic investigations showed growth retardation and ultrastructural differences in the tegument and sub-tegumental tissues as well as in the parenchymal cells of schistosomula from M. fortis compared with those in BALB/c mice. Then, microarray analysis revealed significant differential expression between the schistosomula from the two rodents, with 3,293 down-regulated (by ≥2-fold) and 71 up-regulated (≥2 fold) genes in schistosomula from the former. The up-regulated genes included a proliferation-related gene encoding granulin (Grn) and tropomyosin. Genes that were down-regulated in schistosomula from M. fortis included apoptosis-inhibited genes encoding a baculoviral IAP repeat-containing protein (SjIAP) and cytokine-induced apoptosis inhibitor (SjCIAP), genes encoding molecules involved in insulin metabolism, long-chain fatty acid metabolism, signal transduction, the transforming growth factor (TGF) pathway, the Wnt pathway and in development. TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) and PI/Annexin V-FITC assays, caspase 3/7 activity analysis, and flow cytometry revealed that the percentages of early apoptotic and late apoptotic and/or necrotic cells, as well as the level of caspase activity, in schistosomula from M. fortis were all significantly higher than in those from BALB/c mice. PMID:21731652

A new nanosecond UV laser at 355 nm: early results of corneal flap cutting in a rabbit model.

PubMed

Trost, Andrea; Schrödl, Falk; Strohmaier, Clemens; Bogner, Barbara; Runge, Christian; Kaser-Eichberger, Alexandra; Krefft, Karolina; Vogel, Alfred; Linz, Norbert; Freidank, Sebastian; Hilpert, Andrea; Zimmermann, Inge; Grabner, Günther; Reitsamer, Herbert A

2013-12-03

A new 355 nm UV laser was used for corneal flap cutting in an animal model and tested for clinical and morphologic alterations. Corneal flaps were created (Chinchilla Bastards; n = 25) with an UV nanosecond laser at 355 nm (150 kHz, pulse duration 850 ps, spot-size 1 μm, spot spacing 6 × 6 μm, side cut Δz 1 μm; cutting depth 130 μm) and pulse energies of 2.2 or 2.5 μJ, respectively. Following slit-lamp examination, animals were killed at 6, 12, and 24 hours after treatment. Corneas were prepared for histology (hematoxylin and eosin [HE], TUNEL-assay) and evaluated statistically, followed by ultrastructural investigations. Laser treatment was tolerated well, flap lift was easier at 2.5 μJ compared with 2.2 μJ. Standard HE at 24 hours revealed intact epithelium in the horizontal cut, with similar increase in corneal thickness at both energies. Irrespective of energy levels, TUNEL assay revealed comparable numbers of apoptotic cells in the horizontal and vertical cut at 6, 12, and 24 hours, becoming detectable in the horizontal cut as an acellular stromal band at 24 hours. Ultrastructural analysis revealed regular morphology in the epi- and endothelium, while in the stroma, disorganized collagen lamellae were detectable representing the horizontal cut, again irrespective of energy levels applied. This new UV laser revealed no epi- nor endothelial damage at energies feasible for corneal flap cutting. Observed corneal swelling was lower compared with existing UV laser studies, albeit total energy applied here was much higher. Observed loss of stromal keratinocytes is comparable with available laser systems. Therefore, this new laser is suitable for refractive surgery, awaiting its test in a chronic environment.

Cytological and ultrastructural studies on root tissues

NASA Technical Reports Server (NTRS)

Slocum, R. D.; Gaynor, J. J.; Galston, A. W.

1984-01-01

The anatomy and fine structure of roots from oat and mung bean seedlings, grown under microgravity conditions for 8 days aboard the Space Shuttle, was examined and compared to that of roots from ground control plants grown under similar conditions. Roots from both sets of oat seedlings exhibited characteristic monocotyledonous tissue organization and normal ultrastructural features, except for cortex cell mitochondria, which exhibited a 'swollen' morphology. Various stages of cell division were observed in the meristematic tissues of oat roots. Ground control and flight-grown mung bean roots also showed normal tissue organization, but root cap cells in the flight-grown roots were collapsed and degraded in appearance, especially at the cap periphery. At the ultrastructural level, these cells exhibited a loss of organelle integrity and a highly-condensed cytoplasm. This latter observation perhaps suggests a differing tissue sensitivity for the two species to growth conditions employed in space flight. The basis for abnormal root cap cell development is not understood, but the loss of these putative gravity-sensing cells holds potential significance for long term plant growth orientation during space flight.

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

PubMed

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.

The biological response chain to pollution: a case study from the "Italian Triangle of Death" assessed with the liverwort Lunularia cruciata.

PubMed

Basile, Adriana; Loppi, Stefano; Piscopo, Marina; Paoli, Luca; Vannini, Andrea; Monaci, Fabrizio; Sorbo, Sergio; Lentini, Marco; Esposito, Sergio

2017-12-01

The liverwort Lunularia cruciata, known for being a species tolerant to pollution able to colonize urban areas, was collected in the town of Acerra (South Italy) to investigate the biological effects of air pollution in one of the three vertices of the so-called Italian Triangle of Death. The ultrastructural damages observed by transmission electron microscopy in specimens collected in Acerra were compared with samples collected in the city center of Naples and in a small rural site far from sources of air pollution (Riccia, Molise, Southern Italy). The biological response chain to air pollution was investigated considering vitality, photosynthetic efficiency, heat shock protein 70 (Hsp70) induction and gene expression levels, and chlorophyll degradation and related ultrastructural alterations. Particularly, a significant increment in Hsp70 expression and occurrence, and modifications in the chloroplasts' ultrastructure can be strictly related to the environmental pollution conditions in the three sites. The results could be interpreted in relation to the use of these parameters as biomarkers for environmental pollution.

Porosity and test ultrastructure of costate and non-costate Bulimina species

NASA Astrophysics Data System (ADS)

Grunert, Patrick; Piller, Werner E.

2017-04-01

SEM-based investigations of porosity and test wall ultrastructure of Recent costate and non-costate Bulimina species reveal significant differences in pore diameter, pore density and ultrastructural architecture between these two groups. Costate tests of B. inflata and B. mexicana display low pore density, a large pore diameter, and test walls built by a single type of columnar ultrastructural elements. In contrast, non-costate tests of B. aculeata and B. marginata are characterized by significantly higher pore density, smaller pore diameter, and an additional type of ultrastructural elements formed by oblique, tabular crystallite units which encase the pore channels. We interpret the observed combination of traits in B. aculeata and B. marginata as a set of adaptations to poorly oxygenated, intermediate to deep infaunal microhabitats which they typically occupy today. The evolutionary trend towards increased pore density in this group seemingly involved a major modification of the biomineralisation process resulting in the lining of pore channels with a specific type of ultrastructural element to ensure stability of the densely perforated test.

Ultrastructural evaluation of explanted opacified Hydroview (H60M) intraocular lenses

PubMed Central

Cartwright, Nathaniel E Knox; Mayer, Eric J; McDonald, Brendan M; Skinner, Andrew; Salter, Chris J; Tole, Derek M; Sparrow, John M; Dick, Andrew D; Group, The Bristol IOL Study; Ferguson, David J P

2007-01-01

Aim To describe the ultrastructural appearance of explanted opacified Hydroview H60M intraocular lenses. Methods 14 explanted lenses were examined by scanning electron microscopy, and their appearance compared with a non‐implanted H60M lens from the same time period. Wavelength‐dispersive x ray spectroscopy (WDX) was performed on two opacified lenses. Results Subsurface deposits were seen in all explanted opacified lenses. These deposits broke only onto the surface of more densely opacified lenses. WDX confirmed that the deposits contained both calcium and phosphorous, consistent with their being calcium apatite. Conclusion These findings challenge the widely accepted opinion that H60M intraocular lens opacification begins on the surface of the optic. PMID:16987894

The ultrastructure of cerebral blood capillaries in the ratfish, Chimaera monstrosa.

PubMed

Bundgaard, M

1982-01-01

Sharks and skates (Chondrichthyes: Elasmobranchii) have a glial blood-brain barrier, while all other vertebrates examined so far have an endothelial barrier. For comparative reasons it is desirable to examine the blood-brain barrier in species from the other subclass of cartilaginous fish, the holocephalans. The ultrastructure of cerebral capillaries in the chimaera (Chondrichthyes: Holocephali) is described in the present study. The endothelial cells are remarkably thick. Fenestrae and transendothelial channels were not observed. The endothelial cells are joined by elaborate tight junctions. The perivascular glial processes are separated by wide spaces (15-60 nm) without obliterating junctional complexes. These findings indicate that the chimaera has an endothelial blood-brain barrier.

Comparative ultrastructure of the cuticle of trichostrongyle nematodes.

PubMed

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.

Comparative functional ultrastructure of two hypersaline submerged cyanobacterial mats - Guerrero Negro, Baja California Sur, Mexico, and Solar Lake, Sinai, Egypt

NASA Technical Reports Server (NTRS)

D'Amelio, Elisa D'antoni; Des Marais, David J.; Cohen, Jehuda

1989-01-01

The ultrastructure of the submerged microbial mat from the Solar Lake (SL), Egypt, was compared to that of samples from the Guerrero Negro (GN), Mexico, salt pans. The locations and distributions of the main organisms were determined light microscopy, and the corresponding ultrathin sections were examined under TEM; chemical microprofile analyses were carried out on the day of sampling for microscopic studies. Both communities were found to be dominated by Microleus chthonoplastes, although several morphological species found in the GN mat were absent from the SL mat, including the Tropica nigra and the 'big' Microleus chthonoplastes component. The chemical microprofiles of oxygen, sulfide, pH, and the oxygenic photosynthesis in the two mats were virtually identical. In both mats, the photic zone was restricted to the upper 800 microns of the mat, and oxygenic photosynthesis was detected down to 600 microns.

Wharton's Jelly Derived Mesenchymal Stem Cells: Comparing Human and Horse.

PubMed

Merlo, Barbara; Teti, Gabriella; Mazzotti, Eleonora; Ingrà, Laura; Salvatore, Viviana; Buzzi, Marina; Cerqueni, Giorgia; Dicarlo, Manuela; Lanci, Aliai; Castagnetti, Carolina; Iacono, Eleonora

2018-08-01

Wharton's jelly (WJ) is an important source of mesenchymal stem cells (MSCs) both in human and other animals. The aim of this study was to compare human and equine WJMSCs. Human and equine WJMSCs were isolated and cultured using the same protocols and culture media. Cells were characterized by analysing morphology, growth rate, migration and adhesion capability, immunophenotype, differentiation potential and ultrastructure. Results showed that human and equine WJMSCs have similar ultrastructural details connected with intense synthetic and metabolic activity, but differ in growth, migration, adhesion capability and differentiation potential. In fact, at the scratch assay and transwell migration assay, the migration ability of human WJMSCs was higher (P < 0.05) than that of equine cells, while the volume of spheroids obtained after 48 h of culture in hanging drop was larger than the volume of equine ones (P < 0.05), demonstrating a lower cell adhesion ability. This can also revealed in the lower doubling time of equine cells (3.5 ± 2.4 days) as compared to human (6.5 ± 4.3 days) (P < 0.05), and subsequently in the higher number of cell doubling after 44 days of culture observed for the equine (20.3 ± 1.7) as compared to human cells (8.7 ± 2.4) (P < 0.05), and to the higher (P < 0.05) ability to form fibroblast colonies at P3. Even if in both species tri-lineage differentiation was achieved, equine cells showed an higher chondrogenic and osteogenic differentiation ability (P < 0.05). Our findings indicate that, although the ultrastructure demonstrated a staminal phenotype in human and equine WJMSCs, they showed different properties reflecting the different sources of MSCs.

Successful slush nitrogen vitrification of human ovarian tissue.

PubMed

Talevi, Riccardo; Barbato, Vincenza; Fiorentino, Ilaria; Braun, Sabrina; De Stefano, Cristofaro; Ferraro, Raffaele; Sudhakaran, Sam; Gualtieri, Roberto

2016-06-01

To study whether slush nitrogen vitrification improves the preservation of human ovarian tissue. Control vs. treatment study. University research laboratory. Ovarian biopsies collected from nine women (aged 14-35 years) during laparoscopic surgery for benign gynecologic conditions. None. Ovarian cortical strips of 2 × 5 × 1 mm were vitrified with liquid or slush nitrogen. Fresh and vitrified cortical strips were analyzed for cryodamage and viability under light, confocal, and transmission electron microscopy. Compared with liquid nitrogen, vitrification with slush nitrogen preserves [1] follicle quality (grade 1 follicles: fresh control, 50%; liquid nitrogen, 27%; slush nitrogen, 48%); [2] granulosa cell ultrastructure (intact cells: fresh control, 92%; liquid nitrogen, 45%; slush nitrogen, 73%), stromal cell ultrastructure (intact cells: fresh control, 59.8%; liquid nitrogen, 24%; slush nitrogen, 48.7%), and DNA integrity (TUNEL-positive cells: fresh control, 0.5%; liquid nitrogen, 2.3%; slush nitrogen, 0.4%); and [3] oocyte, granulosa, and stromal cell viability (oocyte: fresh control, 90%; liquid nitrogen, 63%; slush nitrogen, 87%; granulosa cells: fresh control, 93%; liquid nitrogen, 53%; slush nitrogen, 81%; stromal cells: fresh control, 63%; liquid nitrogen, 30%; slush nitrogen, 52%). The histology, ultrastructure, and viability of follicles and stromal cells are better preserved after vitrification with slush nitrogen compared with liquid nitrogen. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Ultrastructural researches on rabbit myxomatosis. Lymphnodal lesions.

PubMed

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.

A Quantitative Approach to Scar Analysis

PubMed Central

Khorasani, Hooman; Zheng, Zhong; Nguyen, Calvin; Zara, Janette; Zhang, Xinli; Wang, Joyce; Ting, Kang; Soo, Chia

2011-01-01

Analysis of collagen architecture is essential to wound healing research. However, to date no consistent methodologies exist for quantitatively assessing dermal collagen architecture in scars. In this study, we developed a standardized approach for quantitative analysis of scar collagen morphology by confocal microscopy using fractal dimension and lacunarity analysis. Full-thickness wounds were created on adult mice, closed by primary intention, and harvested at 14 days after wounding for morphometrics and standard Fourier transform-based scar analysis as well as fractal dimension and lacunarity analysis. In addition, transmission electron microscopy was used to evaluate collagen ultrastructure. We demonstrated that fractal dimension and lacunarity analysis were superior to Fourier transform analysis in discriminating scar versus unwounded tissue in a wild-type mouse model. To fully test the robustness of this scar analysis approach, a fibromodulin-null mouse model that heals with increased scar was also used. Fractal dimension and lacunarity analysis effectively discriminated unwounded fibromodulin-null versus wild-type skin as well as healing fibromodulin-null versus wild-type wounds, whereas Fourier transform analysis failed to do so. Furthermore, fractal dimension and lacunarity data also correlated well with transmission electron microscopy collagen ultrastructure analysis, adding to their validity. These results demonstrate that fractal dimension and lacunarity are more sensitive than Fourier transform analysis for quantification of scar morphology. PMID:21281794

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

PubMed Central

Shahid, Muhammad; Wang, Jianfang; Gu, Xiaolong; Chen, Wei; Ali, Tariq; Gao, Jian; Han, Dandan; Yang, Rui; Fanning, Séamus; Han, Bo

2017-01-01

Prototheca zopfii infections are becoming global concerns in humans and animals. Bovine protothecal mastitis is characterized by deteriorating milk quality and quantity, thus imparting huge economic losses to dairy industry. Previous published studies mostly focused on the prevalence and characterization of P. zopfii from mastitis. However, the ultrastructural pathomorphological changes associated with apoptosis in bovine mammary epithelial cells (bMECs) are not studied yet. Therefore, in this study we aimed to evaluate the in vitro comparative apoptotic potential of P. zopfii genotype-I and -II on bMECs using flow cytometry, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results showed fast growth rate and higher adhesion capability of genotype-II in bMECs as compared with genotype-I. The viability of bMECs infected with P. zopfii genotype-II was significantly decreased after 12 h (p < 0.05) and 24 h (p < 0.01) in comparison with control cells. Contrary, genotype-I couldn't show any significant effects on cell viability. Moreover, after infection of bMECs with genotype-II, the apoptosis increased significantly at 12 h (p < 0.05) and 24 h (p < 0.01) as compared with control group. Genotype-I couldn't display any significant effects on cell apoptosis. The host specificity of P. zopfii was also tested in mouse osteoblast cells, and the results suggest that genotype-I and -II could not cause any significant apoptosis in these cell lines. SEM interpreted the pathomorphological alterations in bMECs after infection. Adhesion of P. zopfii with cells and further disruption of cytomembrane validated the apoptosis caused by genotype-II under SEM. While genotype-1 couldn't cause any significant apoptosis in bMECs. Furthermore, genotype-II induced apoptotic manifested specific ultrastructure features, like cytoplasmic cavitation, swollen mitochondria, pyknosis, cytomembrane disruption, and appearance of apoptotic bodies under 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. PMID:28752077

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

PubMed

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 cells, including the apoptosis of spermatogonial cells, primary spermatocytes, and secondary spermatocytes (P<0.05 ). CER can damage the testicular ultrastructure and increase the apoptosis of spermatogenic cells of the male rat in a time-dependent manner, and the apoptosis of spermatogenic cells may be associated with the damage to mitochondria.

Long-term Administration of Salicylate-induced Changes in BDNF Expression and CREB Phosphorylation in the Auditory Cortex of Rats

PubMed Central

Yi, Bin; Wu, Cong; Shi, Runjie; Han, Kun; Sheng, Haibin; Li, Bei; Mei, Ling; Wang, Xueling; Huang, Zhiwu; Wu, Hao

2018-01-01

Hypothesis: We investigated whether salicylate induces tinnitus through alteration of the expression levels of brain-derived neurotrophic factor (BDNF), proBDNF, tyrosine kinase receptor B (TrkB), cAMP-responsive element-binding protein (CREB), and phosphorylated CREB (p-CREB) in the auditory cortex (AC). Background: Salicylate medication is frequently used for long-term treatment in clinical settings, but it may cause reversible tinnitus. Salicylate-induced tinnitus is associated with changes related to central auditory neuroplasticity. Our previous studies revealed enhanced neural activity and ultrastructural synaptic changes in the central auditory system after long-term salicylate administration. However, the underlying mechanisms remained unclear. Methods: Salicylate-induced tinnitus-like behavior in rats was confirmed using gap prepulse inhibition of acoustic startle and prepulse inhibition testing, followed by comparison of the expression levels of BDNF, proBDNF, TrkB, CREB, and p-CREB. Synaptic ultrastructure was observed under a transmission electron microscope. Results: BDNF and p-CREB were upregulated along with ultrastructural changes at the synapses in the AC of rats treated chronically with salicylate (p < 0.05, compared with control group). These changes returned to normal after 14 days of recovery (p > 0.05). Conclusion: Long-term administration of salicylate increased BDNF expression and CREB activation, upregulated synaptic efficacy, and changed synaptic ultrastructure in the AC. There may be a relationship between these factors and the mechanism of tinnitus. PMID:29342042

Sexual competition affects biomass partitioning, carbon-nutrient balance, Cd allocation and ultrastructure of Populus cathayana females and males exposed to Cd stress.

PubMed

Chen, Juan; Duan, Baoli; Xu, Gang; Korpelainen, Helena; Niinemets, Ülo; Li, Chunyang

2016-11-01

Although increasing attention has been paid to plant adaptation to soil heavy metal contamination, competition and neighbor effects have been largely overlooked, especially in dioecious plants. In this study, we investigated growth as well as biochemical and ultrastructural responses of Populus cathayana Rehder females and males to cadmium (Cd) stress under different sexual competition patterns. The results showed that competition significantly affects biomass partitioning, photosynthetic capacity, leaf and root ultrastructure, Cd accumulation, the contents of polyphenols, and structural and nonstructural carbohydrates. Compared with single-sex cultivation, plants of opposite sexes exposed to sexual competition accumulated more Cd in tissues and their growth was more strongly inhibited, indicating enhanced Cd toxicity under sexual competition. Under intrasexual competition, females showed greater Cd accumulation, more serious damage at the ultrastructural level and greater reduction in physiological activity than under intersexual competition, while males performed better under intrasexual competition than under intersexual competition. Males improved the female microenvironment by greater Cd uptake and lower resource consumption under intersexual competition. These results demonstrate that the sex of neighbor plants and competition affect sexual differences in growth and in key physiological processes under Cd stress. The asymmetry of sexual competition highlighted here might regulate population structure, and spatial segregation and phytoremediation potential of both sexes in P. cathayana growing in heavy metal-contaminated soils. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

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

PubMed

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.

CADASIL: Ultrastructural insights into the morphology of granular osmiophilic material.

PubMed

Lorenzi, Teresa; Ragno, Michele; Paolinelli, Francesca; Castellucci, Clara; Scarpelli, Marina; Morroni, Manrico

2017-03-01

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary systemic vascular disorder. Granular osmiophilic material (GOM) is its ultrastructural marker. We reviewed tissue biopsies from CADASIL patients to establish whether ultrastructural observations help clarify the pathogenic mechanism of CADASIL. Given the resemblance of the GOM deposits to the immunoglobulin deposits seen in glomerulonephritis and focal segmental glomerulosclerosis (FSGS), their morphologies were investigated and compared. Skin, skeletal muscle, kidney, and pericardium tissue biopsies from 13 patients with a clinical and molecular diagnosis of CADASIL, and kidney biopsies from five patients with IgA nephropathy and five patients with primary FSGS were subjected to ultrastructural examination. In CADASIL patients, several GOM deposits from all sites were partially or totally surrounded by an electron-lucent halo. The deposits frequently had a more electron-dense portion with a regular outline on the inner side and a less osmiophilic, looser outer side displaying a less regular profile. The uniformly dense deposits tended to be more osmiophilic if located close to the cell membrane and less osmiophilic if laid farther away from it. The immunoglobulin deposits from the glomerulonephritis and FSGS patients lacked both the granular pattern and the halo. This study demonstrates that GOM deposits may have a nonuniform morphology and describes in detail an electron-lucent halo surrounding several of them. It is conceivable that the halo is the morphological evidence and possibly the cause of an aberrant NOTCH3 processing, already suspected to be involved in CADASIL.

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

PubMed

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.

Serial Section Scanning Electron Microscopy (S3EM) on Silicon Wafers for Ultra-Structural Volume Imaging of Cells and Tissues

PubMed Central

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. S3EM 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 µm3 volume of a calyx of Held presynaptic terminal. The approach introduced here, Serial Section SEM (S3EM), 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. S3EM accelerates process duration, is amenable to full automation and can be implemented with standard instrumentation. PMID:22523574

Serial section scanning electron microscopy (S3EM) on silicon wafers for ultra-structural volume imaging of cells and tissues.

PubMed

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.

Psychological Stress Alters Ultrastructure and Energy Metabolism of Masticatory Muscle in Rats

PubMed Central

Chen, Yong-Jin; Huang, Fei; Zhang, Min; Shang, Hai-Yan

2010-01-01

To investigate the effects of psychological stress on the masticatory muscles of rats, a communication box was applied to induce the psychological stress (PS) in rats. The successful establishment of psychological stimulation was confirmed by elevated serum levels of adrenocorticotropic hormone (ACTH) and changed behaviors in the elevated plusmaze apparatus. The energy metabolism of the bilateral masseter muscles was tested via chemocolorimetric analysis, whereas muscle ultrastructure was assessed by electron microscopy. In comparison to the control group, the PS group showed evidence of swollen mitochondria with cristae loss and reduced matrix density in the masticatory muscles after three weeks of stimulation; after five weeks of stimulation, severe vacuolar changes to the mitochondria were observed. Increased vascular permeability of the masticatory muscle capillaries was found in the five-week PS rats. In addition, there was decreased activity of Na+-K+ATPase and Ca2+-ATPase and a simultaneous increase in the activity of lactate dehydrogenase and lactic acid in the masticatory muscles of PS rats. Together, these results indicate that psychological stress induces alterations in the ultrastructure and energy metabolism of masticatory muscles in rats. PMID:21052548

Filling the gap: adding super-resolution to array tomography for correlated ultrastructural and molecular identification of electrical synapses at the C. elegans connectome.

PubMed

Markert, Sebastian Matthias; Britz, Sebastian; Proppert, Sven; Lang, Marietta; Witvliet, Daniel; Mulcahy, Ben; Sauer, Markus; Zhen, Mei; Bessereau, Jean-Louis; Stigloher, Christian

2016-10-01

Correlating molecular labeling at the ultrastructural level with high confidence remains challenging. Array tomography (AT) allows for a combination of fluorescence and electron microscopy (EM) to visualize subcellular protein localization on serial EM sections. Here, we describe an application for AT that combines near-native tissue preservation via high-pressure freezing and freeze substitution with super-resolution light microscopy and high-resolution scanning electron microscopy (SEM) analysis on the same section. We established protocols that combine SEM with structured illumination microscopy (SIM) and direct stochastic optical reconstruction microscopy (dSTORM). We devised a method for easy, precise, and unbiased correlation of EM images and super-resolution imaging data using endogenous cellular landmarks and freely available image processing software. We demonstrate that these methods allow us to identify and label gap junctions in Caenorhabditis elegans with precision and confidence, and imaging of even smaller structures is feasible. With the emergence of connectomics, these methods will allow us to fill in the gap-acquiring the correlated ultrastructural and molecular identity of electrical synapses.

Anabolic effects of chrysin on the ventral male prostate and female prostate of adult gerbils (Meriones unguiculatus).

PubMed

Campos, Mônica S; Ribeiro, Naiara C S; de Lima, Rodrigo F; Santos, Mariana B; Vilamaior, Patrícia S L; Regasini, Luis O; Biancardi, Manoel F; Taboga, Sebastião R; Santos, Fernanda C A

2018-03-07

Chrysin is a bioflavonoid found in fruits, flowers, tea, honey and wine, which has antioxidant, anti-inflammatory, antiallergic and anticarcinogenic properties. This flavone has also been considered as beneficial for reproduction due its testosterone-boosting potential. Thus, the aim of this study was to evaluate the effects of chrysin on the prostate and gonads of male and female adult gerbils. In addition, a comparative analysis of the effects of testosterone on these same organs was conducted. Ninety-day-old male and female gerbils were treated with chrysin (50mgkg-1day-1) or testosterone cypionate (1mgkg-1week-1) for 21 days. The ventral male prostate and female prostate were dissected out for morphological, morphometric-stereological and ultrastructural assays. Testes and ovaries were submitted to morphological and morphometric---stereological analyses. Chrysin treatment caused epithelial hyperplasia and stromal remodelling of the ventral male and female prostate. Ultrastructurally, male and female prostatic epithelial cells in the chrysin group presented marked development of the organelles involved in the biosynthetic-secretory pathway, whereas cellular toxicity was observed only in female glands. Chrysin preserved normal testicular morphology and increased the number of growing ovarian follicles. Comparatively, testosterone treatment was detrimental to the prostate and gonads, since foci of prostatic intraepithelial neoplasia and gonadal degeneration were observed in both sexes. Thus, under the experimental conditions of this study, chrysin was better tolerated than testosterone in the prostate and gonads.

Ultrastructural and Molecular Analyses Reveal Enhanced Nucleolar Activity in Medicago truncatula Cells Overexpressing the MtTdp2α Gene

PubMed Central

Macovei, Anca; Faè, Matteo; Biggiogera, Marco; de Sousa Araújo, Susana; Carbonera, Daniela; Balestrazzi, Alma

2018-01-01

The role of tyrosyl-DNA phosphodiesterase 2 (Tdp2) involved in the repair of 5′-end-blocking DNA lesions is still poorly explored in plants. To gain novel insights, Medicago truncatula suspension cultures overexpressing the MtTdp2α gene (Tdp2α-13C and Tdp2α-28 lines, respectively) and a control (CTRL) line carrying the empty vector were investigated. Transmission electron microscopy (TEM) revealed enlarged nucleoli (up to 44% expansion of the area, compared to CTRL), the presence of nucleolar vacuoles, increased frequency of multinucleolate cells (up to 4.3-fold compared to CTRL) and reduced number of ring-shaped nucleoli in Tdp2α-13C and Tdp2α-28 lines. Ultrastructural data suggesting for enhanced nucleolar activity in MtTdp2α-overexpressing lines were integrated with results from bromouridine incorporation. The latter revealed an increase of labeled transcripts in both Tdp2α-13C and Tdp2α-28 cells, within the nucleolus and in the extra-nucleolar region. MtTdp2α-overexpressing cells showed tolerance to etoposide, a selective inhibitor of DNA topoisomerase II, as evidenced by DNA diffusion assay. TEM analysis revealed etoposide-induced rearrangements within the nucleolus, resembling the nucleolar caps observed in animal cells under transcription impairment. Based on these findings it is evident that MtTdp2α-overexpression enhances nucleolar activity in plant cells. PMID:29868059

The muscle findings in the neuroleptic malignant syndrome associated with lysergic acid diethylamide.

PubMed Central

Behan, W M; Bakheit, A M; Behan, P O; More, I A

1991-01-01

A detailed pathological description of the muscle findings in a case of the neuroleptic malignant syndrome (NMS) following ingestion of lysergic acid diethylamide (LSD) is given, including the first ultrastructural analysis. Focal necrosis, oedema, and hypercontraction of fibres with glycogen and lipid depletion, were identified, all of which had resolved completely a year later. The findings are compared with those in malignant hyperthermia. It is suggested that the results support the view that in NMS, the muscle rigidity is due to central mechanisms and, in both this disorder and malignant hyperthermia, it is responsible for the hyperpyrexia and its life-threatening complications. Images PMID:1940949

Clathrin-independent carriers form a high capacity endocytic sorting system at the leading edge of migrating cells

PubMed Central

Howes, Mark T.; Kirkham, Matthew; Riches, James; Cortese, Katia; Walser, Piers J.; Simpson, Fiona; Hill, Michelle M.; Jones, Alun; Lundmark, Richard; Lindsay, Margaret R.; Hernandez-Deviez, Delia J.; Hadzic, Gordana; McCluskey, Adam; Bashir, Rumasia; Liu, Libin; Pilch, Paul; McMahon, Harvey; Robinson, Phillip J.; Hancock, John F.; Mayor, Satyajit

2010-01-01

Although the importance of clathrin- and caveolin-independent endocytic pathways has recently emerged, key aspects of these routes remain unknown. Using quantitative ultrastructural approaches, we show that clathrin-independent carriers (CLICs) account for approximately three times the volume internalized by the clathrin-mediated endocytic pathway, forming the major pathway involved in uptake of fluid and bulk membrane in fibroblasts. Electron tomographic analysis of the 3D morphology of the earliest carriers shows that they are multidomain organelles that form a complex sorting station as they mature. Proteomic analysis provides direct links between CLICs, cellular adhesion turnover, and migration. Consistent with this, CLIC-mediated endocytosis of key cargo proteins, CD44 and Thy-1, is polarized at the leading edge of migrating fibroblasts, while transient ablation of CLICs impairs their ability to migrate. These studies provide the first quantitative ultrastructural analysis and molecular characterization of the major endocytic pathway in fibroblasts, a pathway that provides rapid membrane turnover at the leading edge of migrating cells. PMID:20713605

Image analysis of pubic bone for age estimation in a computed tomography sample.

PubMed

López-Alcaraz, Manuel; González, Pedro Manuel Garamendi; Aguilera, Inmaculada Alemán; López, Miguel Botella

2015-03-01

Radiology has demonstrated great utility for age estimation, but most of the studies are based on metrical and morphological methods in order to perform an identification profile. A simple image analysis-based method is presented, aimed to correlate the bony tissue ultrastructure with several variables obtained from the grey-level histogram (GLH) of computed tomography (CT) sagittal sections of the pubic symphysis surface and the pubic body, and relating them with age. The CT sample consisted of 169 hospital Digital Imaging and Communications in Medicine (DICOM) archives of known sex and age. The calculated multiple regression models showed a maximum R (2) of 0.533 for females and 0.726 for males, with a high intra- and inter-observer agreement. The method suggested is considered not only useful for performing an identification profile during virtopsy, but also for application in further studies in order to attach a quantitative correlation for tissue ultrastructure characteristics, without complex and expensive methods beyond image analysis.

Malignant Brenner tumor. A histologic, morphometrical, immunohistochemical, and ultrastructural study.

PubMed

Seldenrijk, C A; Willig, A P; Baak, J P; Kühnel, R; Rao, B R; Burger, C W; van der Harten, J J; Dijkhuizen, G H; Meijer, C J

1986-08-01

The histologic, morphometric, immunohistochemical, and ultrastructural study of a malignant Brenner tumor in a postmenopausal women presenting with vaginal bleeding is described. A comparison with transitional cell carcinomas is made, and the use of morphometry in grading the urothelial-like epithelium in malignant Brenner tumors is suggested. High preoperative urinary estrogen, low serum luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels and histologically confirmed atypical endometrial hyperplasia suggested a hyperestrogenism. The reduction in urinary estrogen and the increase in serum LH and FSH after tumor removal and the presence of aromatase activity detected in tumor microsomes confirmed that the tumor was synthesizing estrogen. Estrogen receptors were undetectable both by biochemical and histochemical analysis in the tumor.

In situ X-ray scattering evaluation of heat-induced ultrastructural changes in dental tissues and synthetic hydroxyapatite

PubMed Central

Sui, Tan; Sandholzer, Michael A.; Lunt, Alexander J. G.; Baimpas, Nikolaos; Smith, Andrew; Landini, Gabriel; Korsunsky, Alexander M.

2014-01-01

Human dental tissues consist of inorganic constituents (mainly crystallites of hydroxyapatite, HAp) and organic matrix. In addition, synthetic HAp powders are frequently used in medical and chemical applications. Insights into the ultrastructural alterations of skeletal hard tissues exposed to thermal treatment are crucial for the estimation of temperature of exposure in forensic and archaeological studies. However, at present, only limited data exist on the heat-induced structural alterations of human dental tissues. In this paper, advanced non-destructive small- and wide angle X-ray scattering (SAXS/WAXS) synchrotron techniques were used to investigate the in situ ultrastructural alterations in thermally treated human dental tissues and synthetic HAp powders. The crystallographic properties were probed by WAXS, whereas HAp grain size distribution changes were evaluated by SAXS. The results demonstrate the important role of the organic matrix that binds together the HAp crystallites in responding to heat exposure. This is highlighted by the difference in the thermal behaviour between human dental tissues and synthetic HAp powders. The X-ray analysis results are supported by thermogravimetric analysis. The results concerning the HAp crystalline architecture in natural and synthetic HAp powders provide a reliable basis for deducing the heating history for dental tissues in the forensic and archaeological context, and the foundation for further development and optimization of biomimetic material design. PMID:24718447

Quantitative and ultrastructural analysis of inflammatory infiltrates in male pattern alopecia.

PubMed

Sueki, H; Stoudemayer, T; Kligman, A M; Murphy, G F

1999-09-01

In order to determine whether lymphocytic inflammation around the lower infundibula in male pattern alopecia is incidental or a general phenomenon, we performed morphometric and ultrastructural analysis of inflammatory infiltrates in the transitional zones of the vertex and occipital hairy scalps of 19 patients with male pattern alopecia. Six normal subjects served as controls. The number of inflammatory infiltrates around the follicular infundibula of the alopecic vertices and non-alopecic occiputs of male pattern alopecia patients was significantly greater than the corresponding control value. The number of mast cells in the widened fibrous tracts in the vertices of male pattern alopecia patients was significantly greater than those in the adventitial fibrotic sheaths of control subjects and the non-alopecic occiputs of male pattern alopecia patients. These data support the idea that the inflammatory process may be, at least in part, responsible for the development of male pattern alopecia.

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.

PubMed

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 particles/micrograms2, P < 0.03) before the onset of luteinizing hormone surge, and the second at 18.00 (16 +/- 2 particles/micrograms2, P < 0.01) concomitantly with the luteinizing hormone surge, when compared to baseline values on proestrus 10.00 (8 +/- particles/micrograms2).

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

PubMed

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 spermatogenic disruption promoted by cadmium, and thus could be a promising form of therapy against male infertility. © 2015 The Authors. International Journal of Experimental Pathology © 2015 International Journal of Experimental Pathology.

Changes in ultrastructure and responses of antioxidant systems of algae (Dunaliella salina) during acclimation to enhanced ultraviolet-B radiation.

PubMed

Tian, Jiyuan; Yu, Juan

2009-12-02

Because of depletion of the stratospheric ozone layer, levels of solar ultraviolet-B (UV-B) radiation (280-315 nm), which penetrates the water column to an ecologically-significant depth, are increasing. In order to assess changes in ultrastructure and responses of antioxidant systems of algae during acclimation to enhanced ultraviolet-B radiation, Dunaliella salina was treated with higher dose of UV-B radiation (13.2 kJm(-2) d(-1) dose) in this study. As compared to the control panel (8.8 kJm(-2) d(-1)), the treatment D. salina had many changes in ultrastructures: (1) thylakoids became swelled, and some of them penetrated into the pyrenoid; (2) lipid globules accumulated; (3) the amounts of starch grains increased; (4) cristae of mitochondria disintegrated; (5) inclusions in vacuoles reduced; and (6) cisternae of Golgi dictyosomes became loose and swollen. Enhanced UV-B irradiation also induced different responses of the antioxidant systems in D. salina: (1) contents of TBARS (thiobarbituric acid reacting substance) and H(2)O(2) increased significantly (p<0.05); (2) levels of MAAs (mycosporine-like amino acids) increased at the beginning and subsequently decreased, and finally they leveled off at lower values; (3) there were not apparent variations for carotenoid contents, and contents of chlorophyll a presented a trend of initial increase and ultimate decrease; (4) both ascorbate and glutathione contents increased significantly (p<0.05); and (5) for the enzyme activities, POD activities increased remarkably (p<0.05), and SOD activities declined apparently (p<0.05), and CAT activity in D. salina had slight variations (p>0.05). In addition, growth curve displayed that enhanced UV-B radiation prominently inhibited increase of cell concentration when compared with control panel (p<0.05). Our results indicated that enhanced UV-B radiation caused ultrastructural changes of D. salina and induced different responses of antioxidant systems in D. salina.

Nano Scale Mechanical Analysis of Biomaterials Using Atomic Force Microscopy

NASA Astrophysics Data System (ADS)

Dutta, Diganta

The atomic force microscope (AFM) is a probe-based microscope that uses nanoscale and structural imaging where high resolution is desired. AFM has also been used in mechanical, electrical, and thermal engineering applications. This unique technique provides vital local material properties like the modulus of elasticity, hardness, surface potential, Hamaker constant, and the surface charge density from force versus displacement curve. Therefore, AFM was used to measure both the diameter and mechanical properties of the collagen nanostraws in human costal cartilage. Human costal cartilage forms a bridge between the sternum and bony ribs. The chest wall of some humans is deformed due to defective costal cartilage. However, costal cartilage is less studied compared to load bearing cartilage. Results show that there is a difference between chemical fixation and non-chemical fixation treatments. Our findings imply that the patients' chest wall is mechanically weak and protein deposition is abnormal. This may impact the nanostraws' ability to facilitate fluid flow between the ribs and the sternum. At present, AFM is the only tool for imaging cells' ultra-structure at the nanometer scale because cells are not homogeneous. The first layer of the cell is called the cell membrane, and the layer under it is made of the cytoskeleton. Cancerous cells are different from normal cells in term of cell growth, mechanical properties, and ultra-structure. Here, force is measured with very high sensitivity and this is accomplished with highly sensitive probes such as a nano-probe. We performed experiments to determine ultra-structural differences that emerge when such cancerous cells are subject to treatments such as with drugs and electric pulses. Jurkat cells are cancerous cells. These cells were pulsed at different conditions. Pulsed and non-pulsed Jurkat cell ultra-structures were investigated at the nano meter scale using AFM. Jurkat cell mechanical properties were measured under different conditions. In addition, AFM was used to measure the charge density of cell surface in physiological conditions. We found that the treatments changed the cancer cells' ultra-structural and mechanical properties at the nanometer scale. Finally, we used AFM to characterize many non-biological materials with relevance to biomedical science. Various metals, polymers, and semi-conducting materials were characterized in air and multiple liquid media through AFM - techniques from which a plethora of industries can benefit. This applies especially to the fledging solar industry which has found much promise in nanoscopic insights. Independent of the material being examined, a reliable method to measure the surface force between a nano probe and a sample surface in a variety of ionic concentrations was also found in the process of procuring these measurements. The key findings were that the charge density increases with the increase of the medium's ionic concentration.

Small angle X-ray scattering as a high-throughput method to classify antimicrobial modes of action.

PubMed

von Gundlach, A R; Garamus, V M; Gorniak, T; Davies, H A; Reischl, M; Mikut, R; Hilpert, K; Rosenhahn, A

2016-05-01

Multi-drug resistant bacteria are currently undermining our health care system worldwide. While novel antimicrobial drugs, such as antimicrobial peptides, are urgently needed, identification of new modes of action is money and time consuming, and in addition current approaches are not available in a high throughput manner. Here we explore how small angle X-ray scattering (SAXS) as high throughput method can contribute to classify the mode of action for novel antimicrobials and therefore supports fast decision making in drug development. Using data bases for natural occurring antimicrobial peptides or predicting novel artificial peptides, many candidates can be discovered that will kill a selected target bacterium. However, in order to narrow down the selection it is important to know if these peptides follow all the same mode of action. In addition, the mode of action should be different from conventional antibiotics, in consequence peptide candidates can be developed further into drugs against multi-drug resistant bacteria. Here we used one short antimicrobial peptide with unknown mode of action and compared the ultrastructural changes of Escherichia coli cells after treatment with the peptide to cells treated with classic antibiotics. The key finding is that SAXS as a structure sensitive tool provides a rapid feedback on drug induced ultrastructural alterations in whole E. coli cells. We could demonstrate that ultrastructural changes depend on the used antibiotics and their specific mode of action. This is demonstrated using several well characterized antimicrobial compounds and the analysis of resulting SAXS curves by principal component analysis. To understand the result of the PCA analysis, the data is correlated with TEM images. In contrast to real space imaging techniques, SAXS allows to obtain nanoscale information averaged over approximately one million cells. The measurement takes only seconds, while conventional tests to identify a mode of action require days or weeks per single substance. The antimicrobial peptide showed a different mode of action as all tested antibiotics including polymyxin B and is therefore a good candidate for further drug development. We envision SAXS to become a useful tool within the high-throughput screening pipeline of modern drug discovery. This article is part of a Special Issue entitled: Antimicrobial peptides edited by Karl Lohner and Kai Hilpert. Copyright © 2015 Elsevier B.V. All rights reserved.

Changes in concentrations of cortisol and melatonin in plasma, expression of synaptophysin, and ultrastructural properties of pinealocytes in goat kids in situations of stress due to early weaning: the effect of melatonin.

PubMed

Redondo, E; Franco, A; Garcia, A; Masot, A J

2010-06-01

To analyse the changes in some histo-physiological parameters of the pineal gland of goat kids in situations of stress due to early weaning, and the effect of exogenous treatment with melatonin. Twenty-four 6-day-old Verata goat kids were used; 12 suckled their dams throughout the study (non-weaned groups), and the other 12 were removed from their dams and fed a milk replacer (weaned groups). Six goat kids in each group were treated with melatonin, and the other six with double-distilled pyrogen-free water (Day 0). On Days 28-29, blood samples were collected at 0600, 1000, 1400, 1800, 2200, 0200 and 0600 hours, to determine concentrations of cortisol and melatonin in plasma. On Days 29 and 30, six animals per group (three at 1400 and three at 0200 hours, respectively) were subject to euthanasia and the weight of their pineal glands determined. The structural immunocytochemistry, morphometric analysis, ultrastructural analysis and immunotransmission electron microscopy of the pineal glands were established. Concentrations of cortisol in plasma were significantly higher in weaned than in non-weaned goat kids (p<0.05), and treatment with melatonin reduced the concentrations in weaned kids (p<0.05). Concentrations of melatonin in plasma showed a similar pattern in the four groups, with peak values at 0200 and troughs at 1400 hours. Mean concentrations of melatonin in plasma in weaned goat kids were significantly lower than those in the other groups (p<0.05). In weaned goat kids not treated with melatonin, the weight and volume of the pineal gland, and number of pinealocytes, were significantly lower when compared with those from non-weaned kids (p<0.05). Quantitative ultrastructural analysis of pinealocytes showed the relative volume of mitochondria, rough endoplasmic reticulum and Golgi complex was significantly lower in weaned than non-weaned goat kids (p<0.05); treatment with melatonin significantly increased these parameters in weaned kids. Taken together, these results indicate that treatment with melatonin in goat kids in situations of stress due to premature weaning could play an important role in the improvement of histo-physiological function of the pineal gland.

SOME ULTRASTRUCTURAL EFFECTS OF INSULIN, HYDROCORTISONE, AND PROLACTIN ON MAMMARY GLAND EXPLANTS

PubMed Central

Mills, Elinor S.; Topper, Yale J.

1970-01-01

The effects of insulin, hydrocortisone, and prolactin on the morphology of explants from midpregnant mouse mammary glands were studied. Insulin promotes the formation of daughter cells within the alveolar epithelium which are ultrastructurally indistinguishable from the parent cells. The addition of hydrocortisone to the medium containing insulin brings the daughter cells to a new, intermediate level of ultrastructural development by effecting an extensive increase of the rough endoplasmic reticulum (RER) throughout the cytoplasm and an increase in the lateral paranuclear Golgi apparatus. When prolactin is added to the insulin-hydrocortisone medium, the daughter cells complete their ultrastructural differentiation. There is a translocation of the RER, Golgi apparatus, and nucleus and the appearance of secretory protein granules within the cytoplasm. There is excellent correlation between the ultrastructural appearance of the alveoli and their capacity to synthesize casein. PMID:5460752

Thymus vulgaris essential oil and thymol against Alternaria alternata (Fr.) Keissler: effects on growth, viability, early infection and cellular mode of action.

PubMed

Perina, Fabiano J; Amaral, Douglas C; Fernandes, Rafael S; Labory, Claudia Rg; Teixeira, Glauco A; Alves, Eduardo

2015-10-01

In initial assays, Thymus vulgaris essential oil (TEO) has demonstrated activity against several plant-pathogenic fungi and has reduced the fungal diseases to levels comparable with commercial fungicides. Thus, the goal of this work was to identify the mode of action in fungi of TEO and its major compound thymol (TOH) at the cellular level using an ultrastructure approach. TEO from leaves and TOH had minimum inhibitory concentrations (MICs) of 500 and 250 µg mL(-1) respectively against A. alternata; under the same conditions, MIC for a commercial fungicide was 1250 µg mL(-1) . Ultrastructure analysis showed that TOH phenolic substance prevented fungal growth, reduced fungal viability and prevented the penetration in fruits by a cell wall/plasma membrane interference mode of action with organelles targeted for destruction in the cytoplasm. Such mode of action differs from protective and preventive-curative commercial fungicides used as pattern control. These findings suggest that TOH was responsible for the antifungal activity of TEO. Therefore, both the essential oil and its major substance have potential for use in the development of new phenolic structures and analogues to control Alternaria brown spot disease caused by Alternaria alternata. © 2014 Society of Chemical Industry.

FLIPPER, a combinatorial probe for correlated live imaging and electron microscopy, allows identification and quantitative analysis of various cells and organelles.

PubMed

Kuipers, Jeroen; van Ham, Tjakko J; Kalicharan, Ruby D; Veenstra-Algra, Anneke; Sjollema, Klaas A; Dijk, Freark; Schnell, Ulrike; Giepmans, Ben N G

2015-04-01

Ultrastructural examination of cells and tissues by electron microscopy (EM) yields detailed information on subcellular structures. However, EM is typically restricted to small fields of view at high magnification; this makes quantifying events in multiple large-area sample sections extremely difficult. Even when combining light microscopy (LM) with EM (correlated LM and EM: CLEM) to find areas of interest, the labeling of molecules is still a challenge. We present a new genetically encoded probe for CLEM, named "FLIPPER", which facilitates quantitative analysis of ultrastructural features in cells. FLIPPER consists of a fluorescent protein (cyan, green, orange, or red) for LM visualization, fused to a peroxidase allowing visualization of targets at the EM level. The use of FLIPPER is straightforward and because the module is completely genetically encoded, cells can be optimally prepared for EM examination. We use FLIPPER to quantify cellular morphology at the EM level in cells expressing a normal and disease-causing point-mutant cell-surface protein called EpCAM (epithelial cell adhesion molecule). The mutant protein is retained in the endoplasmic reticulum (ER) and could therefore alter ER function and morphology. To reveal possible ER alterations, cells were co-transfected with color-coded full-length or mutant EpCAM and a FLIPPER targeted to the ER. CLEM examination of the mixed cell population allowed color-based cell identification, followed by an unbiased quantitative analysis of the ER ultrastructure by EM. Thus, FLIPPER combines bright fluorescent proteins optimized for live imaging with high sensitivity for EM labeling, thereby representing a promising tool for CLEM.

Clinicopathologic correlations in Alibert-type mycosis fungoides.

PubMed

Eng, A M; Blekys, I; Worobec, S M

1981-06-01

Five cases of mycosis fungoides of the Alibert type were studied by taking multiple biopsy specimens at different stages of the disease. Large hyperchromatic, slightly irregular mononuclear cells are the most frequent cells. Ultrastructurally, the cells were only slightly convoluted, had prominent heterochromatin banding at the nuclear membrane, and unremarkable cytoplasmic organelles. Highly convoluted cerebriform nucleated cells were few. Large regular vesicular histiocytes were prominent in the early stages. Ultrastructurally, the cells showed evenly distributed euchromatin. Epidermotrophism was equally as important as Pautrier's abscess as a hallmark of the disease. Stereologic techniques comparing the infiltrate with regard to size and convolution of cells in all stages of mycosis fungoides with infiltrates seen in a variety of benign dermatoses showed no statistically significant differences.

Ultrastructure of the spermatozoa from a Florida manatee (Trichechus manatus latirostris).

PubMed

Miller, D L; Dougherty, M M; Decker, S J; Bossart, G D

2001-08-01

Semen was opportunistically collected from a free-ranging, 10-year-old, 275 cm (total length) Florida manatee (Trichechus manatus latirostris) during rehabilitation treatments. Ultrastructure of the spermatozoa was examined by scanning and transmission electron microscopy and differed slightly from that described for other mammals. Comparisons to the manatee's closest phylogenetic relatives, the elephant and hyrax, were made. The manatee spermatozoa had a similar acrosome but a distinct annulus and lacked the dense bodies observed in the neck of the elephant spermatozoa. Additionally, manatee spermatozoa lacked the lateral vacuoles observed in the nuclear chromatin from of the hyrax spermatozoa. These data add to our understanding of manatees and allow for comparative studies with other species that may be useful in phylogenetic and reproductive studies.

Micromorphology of trichomes of Thymus malyi (Lamiaceae).

PubMed

Marin, M; Koko, V; Duletić-Lausević, S; Marin, P D

2008-12-01

Micromorphological, ultrastructural and morphometric investigations of the trichomes of Thymus malyi were carried out using a light microscope, a scanning electron microscope and a transmission electron microscope. Unbranched non-glandular trichomes, peltate and capitate glandular trichomes were described. The leaves of Thymus malyi bear non-glandular and glandular trichomes on both sides. Estimates of the volume density (i.e. their volume fraction per unit volume) of non-glandular trichomes were higher as compared to volume density of peltate and capitate glandular trichomes. Estimates of the number of these trichomes per area on sections showed that the capitate trichomes were the most abundant. Ultrastructural analyses of cell inner structure have shown numerous mitochondria, big nuclei and plastids with lipid globules and starch grains.

Large Gradient High Magnetic Fields Affect Osteoblast Ultrastructure and Function by Disrupting Collagen I or Fibronectin/αβ1 Integrin

PubMed Central

Qian, Ai-Rong; Gao, Xiang; Zhang, Wei; Li, Jing-Bao; Wang, Yang; Di, Sheng-Meng; Hu, Li-Fang; Shang, Peng

2013-01-01

The superconducting magnet generates a field and field gradient product that can levitate diamagnetic materials. In this study a specially designed superconducting magnet with a large gradient high magnetic field (LG-HMF), which can provide three apparent gravity levels (μ-g, 1-g, and 2-g), was used to simulate a space-like gravity environment. The effects of LG-HMF on the ultrastructure and function of osteoblast-like cells (MG-63 and MC3T3-E1) and the underlying mechanism were investigated by transmission electromicroscopy (TEM), MTT, and cell western (ICW) assays. Under LG-HMF significant morphologic changes in osteoblast-like cells occurred, including expansion of endoplasmic reticulum and mitochondria, an increased number of lysosomes, distorted microvilli, and aggregates of actin filaments. Compared to controls, cell viability and alkaline phosphatase (ALP) secretion were significantly increased, and collagen I (col I), fibronectin (FN), vinculin, integrin α3, αv, and β1 expression were changed under LG-HMF conditions. In conclusion, LG-HMF affects osteoblast ultrastructure, cell viability, and ALP secretion, and the changes caused by LG-HMF may be related to disrupting col I or FN/αβ1 integrin. PMID:23382804

Electroacupuncture ameliorates post-stroke learning and memory through minimizing ultrastructural brain damage and inhibiting the expression of MMP-2 and MMP-9 in cerebral ischemia-reperfusion injured rats.

PubMed

Lin, Ruhui; Yu, Kunqiang; Li, Xiaojie; Tao, Jing; Lin, Yukun; Zhao, Congkuai; Li, Chunyan; Chen, Li-Dian

2016-07-01

The aim of the present study was to investigate the potential neuroprotective effects of electroacupuncture (EA) in the treatment of cerebral ischemia/reperfusion (I/R) injury, and to elucidate the association between this neuroprotective effect and brain ultrastructure and expression of matrix metalloproteinase (MMP)‑2 and 9. Rats underwent focal cerebral I/R injury by arterial ligation and received in vivo therapeutic EA at the Baihui (DU20) and Shenting (DU24) acupoints. The therapeutic efficacy was then evaluated following the surgery. The results of the current study demonstrated that EA treatment significantly ameliorated neurological deficits and reduced cerebral infarct volume compared with I/R injured rats. Furthermore, EA improved the learning and memory ability of rats following I/R injury, inhibited blood brain barrier breakdown and reduced neuronal damage in the ischemic penumbra. Furthermore, EA attenuated ultrastructural changes in the brain tissue following ischemia and inhibited MMP‑2/MMP‑9 expression in cerebral I/R injured rats. The results suggest that EA ameliorates anatomical deterioration, and learning and memory deficits in rats with cerebral I/R injury.

Effects of long-term salicylate administration on synaptic ultrastructure and metabolic activity in the rat CNS

PubMed Central

Yi, Bin; Hu, Shousen; Zuo, Chuantao; Jiao, Fangyang; Lv, Jingrong; Chen, Dongye; Ma, Yufei; Chen, Jianyong; Mei, Ling; Wang, Xueling; Huang, Zhiwu; Wu, Hao

2016-01-01

Tinnitus is associated with neural hyperactivity in the central nervous system (CNS). Salicylate is a well-known ototoxic drug, and we induced tinnitus in rats using a model of long-term salicylate administration. The gap pre-pulse inhibition of acoustic startle test was used to infer tinnitus perception, and only rats in the chronic salicylate-treatment (14 days) group showed evidence of experiencing tinnitus. After small animal positron emission tomography scans were performed, we found that the metabolic activity of the inferior colliculus (IC), the auditory cortex (AC), and the hippocampus (HP) were significantly higher in the chronic treatment group compared with saline group (treated for 14 days), which was further supported by ultrastructural changes at the synapses. The alterations all returned to baseline 14 days after the cessation of salicylate-treatment (wash-out group), indicating that these changes were reversible. These findings indicate that long-term salicylate administration induces tinnitus, enhanced neural activity and synaptic ultrastructural changes in the IC, AC, and HP of rats due to neuroplasticity. Thus, an increased metabolic rate and synaptic transmission in specific areas of the CNS may contribute to the development of tinnitus. PMID:27068004

Ultrastructural Morphology of Sperm from Human Globozoospermia

PubMed Central

Ricci, Giuseppe; Andolfi, Laura; Luppi, Stefania; Boscolo, Rita; Zweyer, Marina; Trevisan, Elisa

2015-01-01

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. PMID:26436098

Ultrastructural and functional characterization of circulating hemocytes from Plutella xylostella larva: cell types and their role in phagocytosis.

PubMed

Huang, Fang; Yang, Yan-yan; Shi, Min; Li, Jun-ying; Chen, Zong-qi; Chen, Fu-shou; Chen, Xue-xin

2010-12-01

The hemocytes of different types encountered in the diamondback moth Plutella xylostella larvae of each instar and the development of the differential hemocytes counts were herein presented. Hemocytes classes/populations characterized based on their affinity with fluorescent dye (acridine orange) and ultrastructural differences comprised the prohemcoytes (<10-16%), plasmatocytes (22-65%), granulocytes (25-72%), oenocytoids (<1-9%), and spherulocytes (<1%). Prohemcoytes were the smallest cells with a comparatively tremendous nucleus. Plasmatocytes and granulocytes occupied the main proportion of total cell numbers. Oenocytoids were in a most stable presence, i.e. rotund in a diameter of 10 μm and with a nucleus deviated from the central location; however, sometimes with two nuclei which were adjoining with each other. Spherulocytes were rare and only could be observed occasionally. Ultrastructural investigation revealed that hemocytes in the diamondback moth larvae were of the typical model as in the Lepidoptera insect larvae. It is interesting to find that the cell which could phagocytize bacteria in vitro was granulocyte, not the other types of hemocytes, although plasmatocyte was usually declared to participate in this reaction in various previous studies. Copyright © 2010 Elsevier Ltd. All rights reserved.

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

PubMed

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.

Peliosis hepatis and sinusoidal dilation during infection by the human immunodeficiency virus (HIV). An ultrastructural study.

PubMed Central

Scoazec, J. Y.; Marche, C.; Girard, P. M.; Houtmann, J.; Durand-Schneider, A. M.; Saimot, A. G.; Benhamou, J. P.; Feldmann, G.

1988-01-01

The description of hepatic sinusoidal lesions in a significant number of acquired immunodeficiency syndrome (AIDS) patients prompted the authors to undertake an ultrastructural study of the sinusoidal barrier abnormalities during human immunodeficiency virus (HIV) infection, in order to compare these lesions with those described in other conditions and to discuss their possible origin. In a series of 29 patients with serologic evidence of HIV infection and liver abnormalities, 8 (28%) had sinusoidal lesions. Peliosis hepatis was present in 2 cases, and sinusoidal dilatation in 6. These patients were classified as follows: 3 AIDS, 4 AIDS-related complex, 1 unclassifiable. Ultrastructural lesions of the sinusoidal barrier were observed in all the cases. They closely mimicked the changes previously reported in peliotic and peliotic-like changes of various origins. A striking particularity was, however, the presence of numerous and hyperplastic sinusoidal macrophages. This work suggests that an injury of the endothelial cells, directly or indirectly related to the presence of HIV, may be incriminated in the pathogenesis of sinusoidal lesions during HIV infection. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:3354642

Knocking Down of Isoprene Emission Modifies the Lipid Matrix of Thylakoid Membranes and Influences the Chloroplast Ultrastructure in Poplar1

PubMed Central

Velikova, Violeta; Müller, Constanze; Ghirardo, Andrea; Rock, Theresa Maria; Aichler, Michaela; Walch, Axel; Schmitt-Kopplin, Philippe

2015-01-01

Isoprene is a small lipophilic molecule with important functions in plant protection against abiotic stresses. Here, we studied the lipid composition of thylakoid membranes and chloroplast ultrastructure in isoprene-emitting (IE) and nonisoprene-emitting (NE) poplar (Populus × canescens). We demonstrated that the total amount of monogalactosyldiacylglycerols, digalactosyldiacylglycerols, phospholipids, and fatty acids is reduced in chloroplasts when isoprene biosynthesis is blocked. A significantly lower amount of unsaturated fatty acids, particularly linolenic acid in NE chloroplasts, was associated with the reduced fluidity of thylakoid membranes, which in turn negatively affects photosystem II photochemical efficiency. The low photosystem II photochemical efficiency in NE plants was negatively correlated with nonphotochemical quenching and the energy-dependent component of nonphotochemical quenching. Transmission electron microscopy revealed alterations in the chloroplast ultrastructure in NE compared with IE plants. NE chloroplasts were more rounded and contained fewer grana stacks and longer stroma thylakoids, more plastoglobules, and larger associative zones between chloroplasts and mitochondria. These results strongly support the idea that in IE species, the function of this molecule is closely associated with the structural organization and functioning of plastidic membranes. PMID:25975835

Ultrastructural evaluation of gingival connective tissue in hereditary gingival fibromatosis.

PubMed

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.

Large gradient high magnetic fields affect osteoblast ultrastructure and function by disrupting collagen I or fibronectin/αβ1 integrin.

PubMed

Qian, Ai-Rong; Gao, Xiang; Zhang, Wei; Li, Jing-Bao; Wang, Yang; Di, Sheng-Meng; Hu, Li-Fang; Shang, Peng

2013-01-01

The superconducting magnet generates a field and field gradient product that can levitate diamagnetic materials. In this study a specially designed superconducting magnet with a large gradient high magnetic field (LG-HMF), which can provide three apparent gravity levels (μ-g, 1-g, and 2-g), was used to simulate a space-like gravity environment. The effects of LG-HMF on the ultrastructure and function of osteoblast-like cells (MG-63 and MC3T3-E1) and the underlying mechanism were investigated by transmission electromicroscopy (TEM), MTT, and cell western (ICW) assays. Under LG-HMF significant morphologic changes in osteoblast-like cells occurred, including expansion of endoplasmic reticulum and mitochondria, an increased number of lysosomes, distorted microvilli, and aggregates of actin filaments. Compared to controls, cell viability and alkaline phosphatase (ALP) secretion were significantly increased, and collagen I (col I), fibronectin (FN), vinculin, integrin α3, αv, and β1 expression were changed under LG-HMF conditions. In conclusion, LG-HMF affects osteoblast ultrastructure, cell viability, and ALP secretion, and the changes caused by LG-HMF may be related to disrupting col I or FN/αβ1 integrin.

Ultrastructure and development of Pleistophora ronneafiei n. sp., a microsporidium (Protista) in the skeletal muscle of an immune-compromised individual.

PubMed

Cali, Ann; Takvorian, Peter M

2003-01-01

This report provides a detailed ultrastructural study of the life cycle, including proliferative and sporogonic developmental stages, of the first Pleistophora species (microsporidium) obtained from an immune-incompetent patient. In 1985, the organism obtained from a muscle biopsy was initially identified as belonging to the genus Pleistophora, based on spore morphology and its location in a sporophorous vesicle. Since that initial report, at least two new microsporidial genera, Trachipleistophora and Brachiola, have been reported to infect the muscle tissue of immunologically compromised patients. Because Trachipleistophora development is similar to Pleistophora, and as Pleistophora was only known to occur in cold-blooded hosts, the question of the proper classification of this microsporidium arose. The information acquired in this study makes it possible to compare Pleistophora sp. (Ledford et al. 1985) to the known human infections and properly determine its correct taxonomic position. Our ultrastructural data have revealed the formation of multinucleate sporogonial plasmodia, a developmental characteristic of the genus Pleistophora and not Trachipleistophora. A comparison with other species of the genus supports the establishment of a new species. This parasite is given the name Pleistophora ronneafiei n. sp.

Ultrastructural characters of the spermatozoa in Digeneans of the genus Lecithochirium Lühe, 1901 (Digenea, Hemiuridae), parasites of fishes: comparative study of L. microstomum and L. musculus

PubMed Central

Ndiaye, Papa Ibnou; Quilichini, Yann; Sène, Aminata; Tkach, Vasyl V.; Bâ, Cheikh Tidiane; Marchand, Bernard

2014-01-01

This study provides the first ultrastructural data of spermatozoa in the genus Lecithochirium. The spermatozoa of L. microstomum (from Trichiurus lepturus in Senegal) and L. musculus (from Anguilla anguilla in Corsica) exhibit the general pattern described in the great majority of the Digenea, namely two axonemes with the 9 + “1” pattern typical of the Trepaxonemata, one mitochondrion, a nucleus, parallel cortical microtubules and external ornamentation of the plasma membrane. Spermatozoa of L. microstomum and L. musculus have some specific features such as the presence of a reduced number of cortical microtubules arranged on only one side of the spermatozoon, the lack of spine-like bodies and expansion of the plasma membrane. The external ornamentation of the plasma membrane entirely covers the anterior extremity of the spermatozoa. The ultrastructure of the posterior extremity of the spermatozoa corresponds to the pattern previously described in the Hemiuridae, characterized by only singlets of the second axoneme. A particularity of these spermatozoa is the organization of the microtubule doublets of the second axoneme around the nucleus in the posterior part of the spermatozoon. PMID:25275216

Electron microscopic features of nasal mucosa treated with topical and circumostial injection of mitomycin C: implications in dacryocystorhinostomy.

PubMed

Ali, Mohammad Javed; Baig, Farhana; Lakshman, Mekala; Naik, Milind N

2015-01-01

To evaluate the ultrastructural effects of topical and circumostial injection of mitomycin C (COS-MMC) on nasal mucosa and compare them with the controls. The study also aimed at classifying the subcellular effects in detail. The nasal mucosa of 6 patients were subjected to 0.02% of mitomycin C for 3 minutes (3 patients) and 0.02% COS-MMC (3 patients) as per standard protocol, during endoscopic dacryocystorhinostomy. Normal nasal mucosa from untreated areas (2 each from topical and COS-MMC groups) were taken as controls after harvesting the treated areas. Full thickness tissues (5 mm × 5 mm) were collected for transmission electron microscopy, and ultrastructural effects were evaluated. Both topical and COS-MMC showed significant and distinct ultrastructural changes involving the epithelial, glandular, vascular, and fibrocollagenous tissues compared with the controls. There were profound changes within fibroblasts with intracellular edema, pleomorphic and vesicular mitochondria, dilated smooth and rough endoplasmic reticulum, and chromatin condensation. In addition, COS-MMC samples showed subepithelial hypocellularity with limited disorganization of structure. The changes in both the MMC groups were restricted to treated areas only. Both topical and COS-MMC show profound changes in nasal mucosa with more marked changes in COS-MMC group. These changes being limited in nature may help in enhancing the success of dacryocystorhinostomy by preventing cicatricial changes of the ostium, especially in high-risk cases such as revision and post-traumatic dacryocystorhinostomy.

Morphological, anatomical, and ultrastructural changes (visualized through scanning electron microscopy) induced in Triticum aestivum by Pb²⁺ treatment.

PubMed

Kaur, Gurpreet; Singh, Harminder Pal; Batish, Daizy Rani; Kohli, Ravinder Kumar

2014-11-01

Lead (Pb) causes severe damage to crops, ecosystems, and humans, and alters the physiology and biochemistry of various plant species. It is hypothesized that Pb-induced metabolic alterations could manifest as structural variations in the roots of plants. In light of this, the morphological, anatomical, and ultrastructural variations (through scanning electron microscopy, SEM) were studied in 4-day-old seedlings of Triticum aestivum grown under Pb stress (0, 8, 16, 40, and 80 mg Pb(2+) l(-1); mild to highly toxic). The toxic effect was more pronounced in radicle growth than on the plumule growth. The SEM of the root of T. aestivum depicted morphological alterations and surface ultrastructural changes. Compared to intact and uniform surface cells in the control roots, cells were irregular and desiccated in Pb(2+)-treated roots. In Pb(2+)-treated roots, the number of root hairs increased manifold, showing dense growth, and these were apparently longer. Apart from the deformity in surface morphology and anatomy of the roots in response to Pb(2+) toxicity, considerable anatomical alterations were also observed. Pb(2+)-treated root exhibited signs of injury in the form of cell distortion, particularly in the cortical cells. The endodermis and pericycle region showed loss of uniformity post Pb(2+) exposure (at 80 mg l(-1) Pb(2+)). The cells appeared to be squeezed with greater depositions observed all over the tissue. The study concludes that Pb(2+) treatment caused structural anomalies and induced anatomical and surface ultrastructural changes in T. aestivum.

Ultrastructure of the mycangium of the southern pine beetle, Dendroctonus frontalis (Coleoptera: Curculionidae, Scolytinae): complex morphology for complex interactions

Treesearch

Cetin Yuceer; Chuan-Yu Hsu; Nadir Erbilgin; Kier D. Klepzig

2011-01-01

The southern pine beetle (SPB) (Dendroctonus frontalis Zimmermann) is the most economically important pest of southern pine forests. Beetles carry fungal cells within specialised cuticular structures, called mycangia. Little is known about the mycangia ultrastructure or function. We used cryo-fracturing and scanning electron microscopy to examine the ultrastructural...

Differential protein partitioning within the herpesvirus tegument and envelope underlies a complex and variable virion architecture

PubMed Central

Bohannon, Kevin Patrick; Jun, Yonggun; Gross, Steven P.; Smith, Gregory Allan

2013-01-01

The herpesvirus virion is a multilayered structure consisting of a DNA-filled capsid, tegument, and envelope. Detailed reconstructions of the capsid are possible based on its icosahedral symmetry, but the surrounding tegument and envelope layers lack regular architecture. To circumvent limitations of symmetry-based ultrastructural reconstruction methods, a fluorescence approach was developed using single-particle imaging combined with displacement measurements at nanoscale resolution. An analysis of 11 tegument and envelope proteins defined the composition and plasticity of symmetric and asymmetric elements of the virion architecture. The resulting virion protein map ascribes molecular composition to density profiles previously acquired by traditional ultrastructural methods, and provides a way forward to examine the dynamics of the virion architecture during infection. PMID:23569236

Differential protein partitioning within the herpesvirus tegument and envelope underlies a complex and variable virion architecture.

PubMed

Bohannon, Kevin Patrick; Jun, Yonggun; Gross, Steven P; Smith, Gregory Allan

2013-04-23

The herpesvirus virion is a multilayered structure consisting of a DNA-filled capsid, tegument, and envelope. Detailed reconstructions of the capsid are possible based on its icosahedral symmetry, but the surrounding tegument and envelope layers lack regular architecture. To circumvent limitations of symmetry-based ultrastructural reconstruction methods, a fluorescence approach was developed using single-particle imaging combined with displacement measurements at nanoscale resolution. An analysis of 11 tegument and envelope proteins defined the composition and plasticity of symmetric and asymmetric elements of the virion architecture. The resulting virion protein map ascribes molecular composition to density profiles previously acquired by traditional ultrastructural methods, and provides a way forward to examine the dynamics of the virion architecture during infection.

Edaravone, a potent free radical scavenger and a calcium channel blocker attenuate isoproterenol induced myocardial infarction by suppressing oxidative stress, apoptotic signaling and ultrastructural damage

PubMed Central

Hassan, Md. Quamrul; Akhtar, Md. Sayeed; Akhtar, Mohd.; Ali, Javed; Haque, Syed Ehtaishamul; Najmi, Abul Kalam

2016-01-01

Objectives: In the present study, we investigated whether combination therapy of low-dose benidipine with the potent free radical scavenger edaravone has a cardioprotective effect against isoproterenol (ISO)-induced myocardial infarction (MI) in Wistar rats. Methods: Rats were pretreated with concurrent doses of benidipine and edaravone (1 μg/kg/day + 1 mg/kg/day and 3 μg/kg/day + 3 mg/kg/day) by intravenous (i.v.) and intraperitoneal (i.p.) routes respectively for 28 days, followed by MI induction using ISO (85 mg/kg) by subcutaneous route for two days at 24 h intervals. After the treatment period, blood was withdrawn and the heart was preserved for biochemical estimations. Results: The activities of the cardiac biomarkers (lactate dehydrogenase and creatine kinase-MB), and the level of malondialdehyde (MDA) significantly increased, while antioxidant markers (reduced glutathione, catalase, superoxidase dismutase, glutathione peroxidase, glutathione reductase) were significantly decreased in the ISO intoxicated group compared with the control group. Moreover, the level of C-reactive protein (CRP) and Caspase-3 activity significantly increased in ISO-intoxicated group. An ultrastructure study was also carried out. Pretreatment with a combination of benidipine and edaravone significantly attenuated the activities of the cardiac biomarkers and the level of MDA, and significantly increased the antioxidant markers compared with the ISO-intoxicated group. Furthermore, pretreatment with the combination of benidipine and edaravone significantly decreased the level of CRP and Caspase-3 activity as compared to the ISO-treated group. The ultrastructure study of myocardium revealed that pretreated groups preserved the mitochondrial shape, the membrane and its internal structures. Conclusion: Taken together these results suggest that the combination of benidipine and edaravone showed significant protective effect in ISO-induced MI. PMID:26868288

Edaravone, a potent free radical scavenger and a calcium channel blocker attenuate isoproterenol induced myocardial infarction by suppressing oxidative stress, apoptotic signaling and ultrastructural damage.

PubMed

Hassan, Md Quamrul; Akhtar, Md Sayeed; Akhtar, Mohd; Ali, Javed; Haque, Syed Ehtaishamul; Najmi, Abul Kalam

2016-08-01

In the present study, we investigated whether combination therapy of low-dose benidipine with the potent free radical scavenger edaravone has a cardioprotective effect against isoproterenol (ISO)-induced myocardial infarction (MI) in Wistar rats. Rats were pretreated with concurrent doses of benidipine and edaravone (1 μg/kg/day + 1 mg/kg/day and 3 μg/kg/day + 3 mg/kg/day) by intravenous (i.v.) and intraperitoneal (i.p.) routes respectively for 28 days, followed by MI induction using ISO (85 mg/kg) by subcutaneous route for two days at 24 h intervals. After the treatment period, blood was withdrawn and the heart was preserved for biochemical estimations. The activities of the cardiac biomarkers (lactate dehydrogenase and creatine kinase-MB), and the level of malondialdehyde (MDA) significantly increased, while antioxidant markers (reduced glutathione, catalase, superoxidase dismutase, glutathione peroxidase, glutathione reductase) were significantly decreased in the ISO intoxicated group compared with the control group. Moreover, the level of C-reactive protein (CRP) and Caspase-3 activity significantly increased in ISO-intoxicated group. An ultrastructure study was also carried out. Pretreatment with a combination of benidipine and edaravone significantly attenuated the activities of the cardiac biomarkers and the level of MDA, and significantly increased the antioxidant markers compared with the ISO-intoxicated group. Furthermore, pretreatment with the combination of benidipine and edaravone significantly decreased the level of CRP and Caspase-3 activity as compared to the ISO-treated group. The ultrastructure study of myocardium revealed that pretreated groups preserved the mitochondrial shape, the membrane and its internal structures. Taken together these results suggest that the combination of benidipine and edaravone showed significant protective effect in ISO-induced MI. © The Author(s), 2016.

Mechanism of Arachidonic Acid Accumulation during Aging in Mortierella alpina: A Large-Scale Label-Free Comparative Proteomics Study.

PubMed

Yu, Yadong; Li, Tao; Wu, Na; Ren, Lujing; Jiang, Ling; Ji, Xiaojun; Huang, He

2016-11-30

Arachidonic acid (ARA) is an important polyunsaturated fatty acid having various beneficial physiological effects on the human body. The aging of Mortierella alpina has long been known to significantly improve ARA yield, but the exact mechanism is still elusive. Herein, multiple approaches including large-scale label-free comparative proteomics were employed to systematically investigate the mechanism mentioned above. Upon ultrastructural observation, abnormal mitochondria were found to aggregate around shrunken lipid droplets. Proteomics analysis revealed a total of 171 proteins with significant alterations of expression during aging. Pathway analysis suggested that reactive oxygen species (ROS) were accumulated and stimulated the activation of the malate/pyruvate cycle and isocitrate dehydrogenase, which might provide additional NADPH for ARA synthesis. EC 4.2.1.17-hydratase might be a key player in ARA accumulation during aging. These findings provide a valuable resource for efforts to further improve the ARA content in the oil produced by aging M. alpina.

Ultrastructural analysis of cell component distribution in the apical cell of Ceratodon protonemata

NASA Technical Reports Server (NTRS)

Walker, L. M.; Sack, F. D.

1995-01-01

A distinctive feature of tip-growing plant cells is that cell components are distributed differentially along the length of the cell, although most ultrastructural analyses have been qualitative. The longtitudinal distribution of cell components was studied both qualitatively and quantitatively in the apical cell of dark-grown protonemata of the moss Ceratodon. The first 35 micrometers of the apical cell was analyzed stereologically using transmission electron microscopy. There were four types of distributions along the cell's axis, three of them differential: (1) tubular endoplasmic reticulum was evenly distributed, (2) cisternal endoplasmic reticulum and Golgi vesicles were distributed in a tip-to-base gradient, (3) plastids, vacuoles, and Golgi stacks were enriched in specific areas, although the locations of the enrichments varied, and (4) mitochondria were excluded in the tip-most 5 micrometers and evenly distributed throughout the remaining 30 micrometers. This study provides one of the most comprehensive quantitative, ultrastructural analyses of the distribution of cell components in the apex of any tip-growing plant cell. The finding that almost every component had its own spatial arrangement demonstrates the complexity of the organization and regulation of the distribution of components in tip-growing cells.

Effects of growth hormone on the ultrastructure of bovine preimplantation embryos.

PubMed

Kölle, Sabine; Stojkovic, Miodrag; Reese, Sven; Reichenbach, Horst-Dieter; Wolf, Eckhard; Sinowatz, Fred

2004-07-01

Growth hormone (GH) has recently been shown to promote the development of preimplantation embryos. The aim of our study was therefore to analyze the effects of GH on the morphology and ultrastructure of the cells of bovine preimplantation embryos produced by in vitro fertilization (IVF). In order to determine the physiologically optimal morphology of blastocysts, ex vivo embryos obtained by uterine flushing were also included in the study. As shown by transmission electron microscopy, treatment with GH induced the elimination of glycogen storage in cells of the inner cell mass of 7-day-old embryos. GH also stimulated the exocytosis of lipid vesicles in the inner cell mass and trophectoderm cells of these embryos. Quantitative analysis of micrographs demonstrated a higher volume density of embryonic mitochondria in 7-day-old embryos cultured with GH than in control embryos. Treatment with GH regularly resulted in an improvement of the ultrastructural features of embryos produced in vitro, thus resembling the morphology of ex vivo embryos. Scanning electron-microscopy studies demonstrated that GH altered the structure and the pore size of the zona pellucida of blastocysts. Our studies imply that GH can modulate carbohydrate, lipid, and energy metabolism and influence transportation processes in the early IVF embryo.

Phytoplasma infection in tomato is associated with re-organization of plasma membrane, ER stacks, and actin filaments in sieve elements.

PubMed

Buxa, Stefanie V; Degola, Francesca; Polizzotto, Rachele; De Marco, Federica; Loschi, Alberto; Kogel, Karl-Heinz; di Toppi, Luigi Sanità; van Bel, Aart J E; Musetti, Rita

2015-01-01

Phytoplasmas, biotrophic wall-less prokaryotes, only reside in sieve elements of their host plants. The essentials of the intimate interaction between phytoplasmas and their hosts are poorly understood, which calls for research on potential ultrastructural modifications. We investigated modifications of the sieve-element ultrastructure induced in tomato plants by 'Candidatus Phytoplasma solani,' the pathogen associated with the stolbur disease. Phytoplasma infection induces a drastic re-organization of sieve-element substructures including changes in plasma membrane surface and distortion of the sieve-element reticulum. Observations of healthy and stolbur-diseased plants provided evidence for the emergence of structural links between sieve-element plasma membrane and phytoplasmas. One-sided actin aggregates on the phytoplasma surface also inferred a connection between phytoplasma and sieve-element cytoskeleton. Actin filaments displaced from the sieve-element mictoplasm to the surface of the phytoplasmas in infected sieve elements. Western blot analysis revealed a decrease of actin and an increase of ER-resident chaperone luminal binding protein (BiP) in midribs of phytoplasma-infected plants. Collectively, the studies provided novel insights into ultrastructural responses of host sieve elements to phloem-restricted prokaryotes.

Phytoplasma infection in tomato is associated with re-organization of plasma membrane, ER stacks, and actin filaments in sieve elements

PubMed Central

Buxa, Stefanie V.; Degola, Francesca; Polizzotto, Rachele; De Marco, Federica; Loschi, Alberto; Kogel, Karl-Heinz; di Toppi, Luigi Sanità; van Bel, Aart J. E.; Musetti, Rita

2015-01-01

Phytoplasmas, biotrophic wall-less prokaryotes, only reside in sieve elements of their host plants. The essentials of the intimate interaction between phytoplasmas and their hosts are poorly understood, which calls for research on potential ultrastructural modifications. We investigated modifications of the sieve-element ultrastructure induced in tomato plants by ‘Candidatus Phytoplasma solani,’ the pathogen associated with the stolbur disease. Phytoplasma infection induces a drastic re-organization of sieve-element substructures including changes in plasma membrane surface and distortion of the sieve-element reticulum. Observations of healthy and stolbur-diseased plants provided evidence for the emergence of structural links between sieve-element plasma membrane and phytoplasmas. One-sided actin aggregates on the phytoplasma surface also inferred a connection between phytoplasma and sieve-element cytoskeleton. Actin filaments displaced from the sieve-element mictoplasm to the surface of the phytoplasmas in infected sieve elements. Western blot analysis revealed a decrease of actin and an increase of ER-resident chaperone luminal binding protein (BiP) in midribs of phytoplasma-infected plants. Collectively, the studies provided novel insights into ultrastructural responses of host sieve elements to phloem-restricted prokaryotes. PMID:26347766

["Vestigial cells" of the transitional area of the uterine-cervix. Comparative morphological study with the subcylindrical-reserve-cells (author's transl)].

PubMed

Minh, H N; Smadja, A; Lecomte, D; Orcel, L; Coupez, F

1982-01-01

The squamo-cylindrical junction represents a transitional area of unstable epithelium. It consists of slightly differentiated cells which disclosed resemblance in morphological pattern with germinal cells of the basal layer in the exocervical squamous epithelium. These unstable cells, according to the authors, may be derived from the cranial, most cephalic extend of the sinusal vaginal plate which had formed the epithelium of the entire vagina and the vaginal portion of the cervix up to the squamo-columnar junction. Ultrastructural analysis disclosed no similarities between cells of the squamo-columnar junction and subcylindrical reserve cells which exhibited sometimes resemblance to the "mesenchymal cells" found within the surrounding stroma.

Connexin 43 expression of foreign body giant cells after implantation of nanoparticulate hydroxyapatite.

PubMed

Herde, Katja; Hartmann, Sonja; Brehm, Ralph; Kilian, Olaf; Heiss, Christian; Hild, Anne; Alt, Volker; Bergmann, Martin; Schnettler, Reinhard; Wenisch, Sabine

2007-11-01

In bone a role of connexin 43 has been implicated with the fusion of mononuclear precursors of the monocyte/macrophage lineage into multinucleated cells. In order to investigate the putative role of connexin 43 in formation of bone osteoclast-like foreign body giant cells which are formed in response to implantation of biomaterials, nanoparticulate hydroxyapatite had been implanted into defects of minipig femura. After 20 days the defect areas were harvested and connexin 43 expression and synthesis were investigated by using immunohistochemistry, Western Blot, and in situ hybridization within macrophages and osteoclast-like foreign body giant cells. Morphological analysis of gap junctions is performed ultrastructurally. As shown on protein and mRNA level numerous connexin 43 positive macrophages and foreign body giant cells (FBGC) were localized within the granulation tissue and along the surfaces of the implanted hydroxyapatite (HA). Besides, the formation of FBGC by fusion of macrophages could be shown ultrastructurally. Connexin 43 labeling observed on the protein and mRNA level could be attributed to gap junctions identified ultrastructurally between macrophages, between FBGC, and between FBGC and macrophages. Annular gap junctions in the cytoplasm of FBGC pointed to degradation of the channels, and the ubiquination that had occurred in the course of degradation was confirmed by Western blot analysis. All in all, the presently observed pattern of connexin 43 labeling refers to an functional role of gap junctional communication in the formation of osteoclast-like foreign body giant cells formed in response to implantation of the nanoparticulate HA.

Features of natural and gonadotropin-releasing hormone antagonist-induced corpus luteum regression and effects of in vivo human chorionic gonadotropin.

PubMed

Del Canto, Felipe; Sierralta, Walter; Kohen, Paulina; Muñoz, Alex; Strauss, Jerome F; Devoto, Luigi

2007-11-01

The natural process of luteolysis and luteal regression is induced by withdrawal of gonadotropin support. The objectives of this study were: 1) to compare the functional changes and apoptotic features of natural human luteal regression and induced luteal regression; 2) to define the ultrastructural characteristics of the corpus luteum at the time of natural luteal regression and induced luteal regression; and 3) to examine the effect of human chorionic gonadotropin (hCG) on the steroidogenic response and apoptotic markers within the regressing corpus luteum. Twenty-three women with normal menstrual cycles undergoing tubal ligation donated corpus luteum at specific stages in the luteal phase. Some women received a GnRH antagonist prior to collection of corpus luteum, others received an injection of hCG with or without prior treatment with a GnRH antagonist. Main outcome measures were plasma hormone levels and analysis of excised luteal tissue for markers of apoptosis, histology, and ultrastructure. The progesterone and estradiol levels, corpus luteum DNA, and protein contents in induced luteal regression resembled those of natural luteal regression. hCG treatment raised progesterone and estradiol in both natural luteal regression and induced luteal regression. The increase in apoptosis detected in induced luteal regression by cytochrome c in the cytosol, activated caspase-3, and nuclear DNA fragmentation, was similar to that observed in natural luteal regression. The antiapoptotic protein Bcl-2 was significantly lower during natural luteal regression. The proapoptotic proteins Bax and Bak were at a constant level. Apoptotic and nonapoptotic death of luteal cells was observed in natural luteal regression and induced luteal regression at the ultrastructural level. hCG prevented apoptotic cell death, but not autophagy. The low number of apoptotic cells disclosed and the frequent autophagocytic suggest that multiple mechanisms are involved in cell death at luteal regression. hCG restores steroidogenic function and restrains the apoptotic process, but not autophagy.

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

PubMed

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.

Ultrastructure and chemical composition of the proboscis hooks of Acanthocephalus lucii (Müller, 1776) (Acanthocephala: Palaeacanthocephala) using X-ray elemental analysis.

PubMed

Brázová, Tímea; Poddubnaya, Larisa G; Miss, Noemí Ramírez; Hanzelová, Vladimíra

2014-12-01

The ultrastructure and chemical composition of the proboscis hooks and surrounding tegument of Acanthocephalus lucii (Müller, 1776), a parasite of European perch, Perca fluviatilis Linnaeus, were examined using scanning (SEM) and transmission (TEM) electron microscopy and X-ray microanalysis (EDXA). The blade of middle hooks consists of three layers: an outer homogeneous layer, an inner heterogeneous layer and a central core. TEM observation revealed the presence of hollow tubes, which spaced the central core; fibrous inner hook layer surrounded by an electron-dense margin and the basal tegumental layer filled with electron-dense bodies and outer layer. We found for the first time that the so-called 'epidermal covering' surrounding of the exposed hook blade (outer hook layer) is a modified striped portion of the tegumental layer and there are no special contact sites between these two morphologically different structures, i.e. striped layer of the syncytial tegument and following proper outer hook layer, which is a homogeneous, moderately electron-dense layer of -0.3 μm in thickness. The hook root is embedded into subtegumental fibrous layer. X-ray microanalysis of both the surface and internal parts of A. lucii hooks demonstrated the presence of calcium, magnesium, phosphorus and sulphur. The highest concentration of sulphur was recorded at the tip of hooks, whereas the middle part of the hooks was most rich in calcium, phosphorus and magnesium. The proximal part of the hooks contained lower concentrations of sulphur, calcium and phosphorus. In the proboscis tegument, only two elements, calcium and silicon, were found. The differences observed in the chemical composition of the hook 'epidermal covering' and the proboscis tegument support our ultrastructural findings that the hook tegumental covering is a modified structure compared with that of the general proboscis tegument.

Effects of long-term space condition on cell ultrastructure and the molecular level change of the tomato

NASA Astrophysics Data System (ADS)

Jinying, L.; Min, L.; Huai, X.; Yi, P.; Chunhua, Z.; Nechitalo, G.

Effects of long-term exposure to physical factors of space flight on dormant seeds were studied on plants derived from tomato seeds flown for 6 years on board of the space station MIR Upon return to the Earth the seeds were germinated and grown to maturity Samples of plants were compared to plants from parallel ground-based controls Various differences of ultrastructure of the tomato leaf cell were observed with an electron microscope One plant carried by space station has the anatomy of leaves with a three-layered palisade tissue and other plants similar with ground controls have the anatomy of leaves with a one-layered palisade tissue The number of starch grains per chloroplast of every space-treated tomato leaf increased significantly compared with that of the ground control The leaf cell walls of two plants carried by space station became contracted and deformed The size of chloroplast in some space-treated plants was larger and the lamellae s structure of some chloroplasts turned curvature and loose The results obtained point out to significant changes occurring on the molecular level among the space-flight treated seedlings and the ground control The leaves of plants were used for AFLP Amplification Fragment Length Polymorphism analysis For the first generation space-flight treated tomato plants among 64 pairs of primers used in this experiment 43 primers generated the same DNA bands type and 21 primers generated a different DNA band type 2582 DNA bands were produced among which 34 DNA bands were polymorphic with the percentage

Comparative ultrastructure of fruit plastids in three genetically diverse genotypes of apple (Malus × domestica Borkh.) during development

PubMed Central

Schaeffer, Scott M.; Christian, Ryan; Castro-Velasquez, Nohely; Hyden, Brennan; Lynch-Holm, Valerie

2017-01-01

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 biochemistry of plastids in perennial non-model systems. PMID:28698906

Intra- and interspecific diversity of ultrastructural markers in Scedosporium.

PubMed

Stepanova, Amaliya A; de Hoog, G Sybren; Vasilyeva, Nataliya V

2016-02-01

Ultrastructural features of conidia, lateral walls of aerial and submerged hyphal cells, and of septal pore apparatus of Scedosporium apiospermum, S. boydii, Pseudallescheria angusta and Scedosporium aurantiacum were studied. Submerged hyphal cells possessed a thick extracellular matrix. Crystalline satellites accessory to the septal pore apparatus were revealed. Fundamental ultrastructural features appeared to be heterogeneous at low taxonomic levels. The closely interrelated members of the S. apiospermum complex showed quantitative ultrastructural variability, but the unambiguously different species S. aurantiacum deviated qualitatively by markers of conidial wall structure, Woronin bodies morphology and presence/absence of crystalline satellites of the septal pore apparatus. Copyright © 2015 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

How effectively does a clinostat mimic the ultrastructural effects of microgravity on plant cells?

NASA Technical Reports Server (NTRS)

Moore, R.

1990-01-01

Columella cells of seedlings of Zea mays L. cv. Bear Hybrid grown in the microgravity of orbital flight allocate significantly larger relative-volumes to hyaloplasm and lipid bodies, and significantly smaller relative-volumes to dictyosomes, plastids, and starch than do columella cells of seedlings grown at 1 g. The ultrastructure of columella cells of seedlings grown at 1 g and on a rotating clinostat is not significantly different. However, the ultrastructure of cells exposed to these treatments differs significantly from that of seedlings grown in microgravity. These results indicate that the actions of a rotating clinostat do not mimic the ultrastructural effects of microgravity in columella cells of Z. mays.

Phagocytosis of photoreceptor outer segments by transplanted human neural stem cells as a neuroprotective mechanism in retinal degeneration.

PubMed

Cuenca, Nicolás; Fernández-Sánchez, Laura; McGill, Trevor J; Lu, Bin; Wang, Shaomei; Lund, Raymond; Huhn, Stephen; Capela, Alexandra

2013-10-15

Transplantation of human central nervous system stem cells (HuCNS-SC) into the subretinal space of Royal College of Surgeons (RCS) rats preserves photoreceptors and visual function. To explore possible mechanism(s) of action underlying this neuroprotective effect, we performed a detailed morphologic and ultrastructure analysis of HuCNS-SC transplanted retinas. The HuCNS-SC were transplanted into the subretinal space of RCS rats. Histologic examination of the transplanted retinas was performed by light and electron microscopy. Areas of the retina adjacent to HuCNS-SC graft (treated regions) were analyzed and compared to control sections obtained from the same retina, but distant from the transplant site (untreated regions). The HuCNS-SC were detected as a layer of STEM 121 immunopositive cells in the subretinal space. In treated regions, preserved photoreceptor nuclei, as well as inner and outer segments were identified readily. In contrast, classic signs of degeneration were observed in the untreated regions. Interestingly, detailed ultrastructure analysis revealed a striking preservation of the photoreceptor-bipolar-horizontal cell synaptic contacts in the outer plexiform layer (OPL) of treated areas, in stark contrast with untreated areas. Finally, the presence of phagosomes and vesicles exhibiting the lamellar structure of outer segments also was detected within the cytosol of HuCNS-SC, indicating that these cells have phagocytic capacity in vivo. This study reveals the novel finding that preservation of specialized synaptic contacts between photoreceptors and second order neurons, as well as phagocytosis of photoreceptor outer segments, are potential mechanism(s) of HuCNS-SC transplantation, mediating functional rescue in retinal degeneration.

Transmission Electron Microscopy Analysis of Epithelial Basement Membrane Repair in Rabbit Corneas With Haze

PubMed Central

Torricelli, Andre A. M.; Singh, Vivek; Agrawal, Vandana; Santhiago, Marcony R.; Wilson, Steven E.

2013-01-01

Purpose. To assess the ultrastructure of the epithelial basement membrane using transmission electron microscopy (TEM) in rabbit corneas with and without subepithelial stroma opacity (haze). Methods. Two groups of eight rabbits each were included in this study. Photorefractive keratectomy (PRK) was performed using an excimer laser. The first group had −4.5-diopter (−4.5D) PRK and the second group had −9.0D PRK. Contralateral eyes were unwounded controls. Rabbits were sacrificed at 4 weeks after surgery. Immunohistochemical analysis was performed to detect the myofibroblast marker α-smooth muscle actin (SMA). TEM was performed to analyze the ultrastructure of the epithelial basement membrane and stroma. Results. At 4 weeks after PRK, α-SMA+ myofibroblasts were present at high density in the subepithelial stroma of rabbit eyes that had −9.0D PRK, along with prominent disorganized extracellular matrix, whereas few myofibroblasts and little disorganized extracellular matrix were noted in eyes that had −4.5D PRK. The epithelial basement membrane was irregular and discontinuous and lacking typical morphology in all corneas at 1 month after −9D PRK compared to corneas at 1 month in the −4.5D PRK group. Conclusions. The epithelial basement membrane acts as a critical modulator of corneal wound healing. Structural and functional defects in the epithelial basement membrane correlate to both stromal myofibroblast development from precursor cells and continued myofibroblast viability, likely through the modulation of epithelial–stromal interactions mediated by cytokines. Prolonged stromal haze in the cornea is associated with abnormal regeneration of the epithelial basement membrane. PMID:23696606

Ultrastructure of the Odontocete organ of Corti: scanning and transmission electron microscopy.

PubMed

Morell, Maria; Lenoir, Marc; Shadwick, Robert E; Jauniaux, Thierry; Dabin, Willy; Begeman, Lineke; Ferreira, Marisa; Maestre, Iranzu; Degollada, Eduard; Hernandez-Milian, Gema; Cazevieille, Chantal; Fortuño, José-Manuel; Vogl, Wayne; Puel, Jean-Luc; André, Michel

2015-02-15

The morphological study of the Odontocete organ of Corti, together with possible alterations associated with damage from sound exposure, represents a key conservation approach to assess the effects of acoustic pollution on marine ecosystems. By collaborating with stranding networks from several European countries, 150 ears from 13 species of Odontocetes were collected and analyzed by scanning (SEM) and transmission (TEM) electron microscopy. Based on our analyses, we first describe and compare Odontocete cochlear structures and then propose a diagnostic method to identify inner ear alterations in stranded individuals. The two species analyzed by TEM (Phocoena phocoena and Stenella coeruleoalba) showed morphological characteristics in the lower basal turn of high-frequency hearing species. Among other striking features, outer hair cell bodies were extremely small and were strongly attached to Deiters cells. Such morphological characteristics, shared with horseshoe bats, suggest that there has been convergent evolution of sound reception mechanisms among echolocating species. Despite possible autolytic artifacts due to technical and experimental constraints, the SEM analysis allowed us to detect the presence of scarring processes resulting from the disappearance of outer hair cells from the epithelium. In addition, in contrast to the rapid decomposition process of the sensory epithelium after death (especially of the inner hair cells), the tectorial membrane appeared to be more resistant to postmortem autolysis effects. Analysis of the stereocilia imprint pattern at the undersurface of the tectorial membrane may provide a way to detect possible ultrastructural alterations of the hair cell stereocilia by mirroring them on the tectorial membrane. © 2014 Wiley Periodicals, Inc.

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

NASA Astrophysics Data System (ADS)

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.

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

PubMed

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.

Processing of Ceramics by Biopolymers. Ultrastructure-Property Relationships in Biocrystals

DTIC Science & Technology

1991-10-09

34brick and mortar" microarchitecture with 0.5-pm-thick aragonite paltelets and a 20-nm-thick organic matrix between them. An analysis performed by TEM...proteins with the precipitates, (iii) analysis of the calcite lattice in terms of protein occlusion (atomic resolution electron microscopy and...crystallites have definite crystallographic orientation relationships on the "in- layer" and "through-thickness" directions. In addition, analysis of

Primary cilia in gastric Gastrointestinal Stromal Tumours (GISTs): an ultrastructural study

PubMed Central

Castiella, Tomás; Muñoz, Guillermo; Luesma, María José; Santander, Sonia; Soriano, Mario; Junquera, Concepción

2013-01-01

Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal (non-epithelial) neoplasms of the human gastrointestinal (GI) tract. They are thought to derive from interstitial cells of Cajal (ICCs) or an ICC progenitor based on immunophenotypical and ultrastructural similarities. Because ICCs show primary cilium, our hypothesis is based on the possibility that some of these neoplastic cells could also present it. To determine this, an exhaustive ultrastructural study has been developed on four gastric GISTs. Previous studies had demonstrated considerable variability in tumour cells with two dominating phenotypes, spindly and epithelioid. In addition to these two types, we have found another cell type reminiscent of adult ICCs with a voluminous nucleus surrounded by narrow perinuclear cytoplasm with long slender cytoplasmic processes. We have also noted the presence of small undifferentiated cells. In this study, we report for the first time the presence of primary cilia (PCs) in spindle and epithelioid tumour cells, an ultrastructural feature we consider of special interest that has hitherto been ignored in the literature dealing with the ultrastructure of GISTs. We also point out the frequent occurrence of multivesicular bodies (MVBs). The ultrastructural findings described in gastric GISTs in this study appear to be relevant considering the critical roles played by PCs and MVBs recently demonstrated in tumourigenic processes. PMID:23672577

Malignant mixed müllerian tumors. An ultrastructural and immunohistochemical analysis with histogenetic considerations.

PubMed

Geisinger, K R; Dabbs, D J; Marshall, R B

1987-05-15

In the female genital tract, malignant mixed müllerian tumors (MMTs) are uncommon neoplasms of uncertain histogenesis. We have examined 11 MMTs by both electron microscopy (EM) and immunoperoxidase techniques (IPX). Eight were of endometrial, two were of ovarian, and one of tubal origins. The IPX analysis included monoclonal antibodies to keratin (k) and vimentin (v) and a polyclonal antibody to myoglobin. Carcinomatous elements were always keratin positive (K+) and were focally positive for vimentin in six tumors. Homologous stromal sarcoma cells were vimentin positive (V+) and in three tumors were focally K+. Ultrastructurally, the epithelial cells were not highly differentiated and the sarcomatous elements generally resembled normal proliferative-phase stromal cells. The epithelial and stromal elements were separated by a thin basal lamina that only rarely and focally had discontinuities. No transitional cellular forms were identified. A definite positive myoglobin reaction was seen in two of the four neoplasms in which rhabdomyoblasts were identified by light microscopy. Myofilaments were identified by electron microscope in three neoplasms.

High-resolution measurements of the multilayer ultra-structure of articular cartilage and their translational potential

PubMed Central

2014-01-01

Current musculoskeletal imaging techniques usually target the macro-morphology of articular cartilage or use histological analysis. These techniques are able to reveal advanced osteoarthritic changes in articular cartilage but fail to give detailed information to distinguish early osteoarthritis from healthy cartilage, and this necessitates high-resolution imaging techniques measuring cells and the extracellular matrix within the multilayer structure of articular cartilage. This review provides a comprehensive exploration of the cellular components and extracellular matrix of articular cartilage as well as high-resolution imaging techniques, including magnetic resonance image, electron microscopy, confocal laser scanning microscopy, second harmonic generation microscopy, and laser scanning confocal arthroscopy, in the measurement of multilayer ultra-structures of articular cartilage. This review also provides an overview for micro-structural analysis of the main components of normal or osteoarthritic cartilage and discusses the potential and challenges associated with developing non-invasive high-resolution imaging techniques for both research and clinical diagnosis of early to late osteoarthritis. PMID:24946278

Edaravone attenuates brain damage in rats after acute CO poisoning through inhibiting apoptosis and oxidative stress.

PubMed

Li, Qin; Bi, Ming Jun; Bi, Wei Kang; Kang, Hai; Yan, Le Jing; Guo, Yun-Liang

2016-03-01

Acute carbon monoxide (CO) poisoning is the most common cause of death from poisoning all over the world and may result in neuropathologic and neurophysiologic changes. Acute brain damage and delayed encephalopathy are the most serious complication, yet their pathogenesis is poorly understood. The present study aimed to evaluate the neuroprotective effects of Edaravone against apoptosis and oxidative stress after acute CO poisoning. The rat model of CO poisoning was established in a hyperbaric oxygen chamber by exposed to CO. Ultrastructure changes were observed by transmission electron microscopy (TEM). TUNEL stain was used to assess apoptosis. Immunohistochemistry and immunofluorescence double stain were used to evaluate the expression levels of heme oxygenase-1 (HO-1) and nuclear factor erythroid 2-related factor 2 (Nrf-2) protein and their relationship. By dynamically monitored the carboxyhemoglobin (HbCO) level in blood, we successfully established rat model of severe CO poisoning. Ultrastructure changes, including chromatin condensation, cytoplasm dissolution, vacuoles formation, nucleus membrane and cell organelles decomposition, could be observed after CO poisoning. Edaravone could improve the ultrastructure damage. CO poisoning could induce apoptosis. Apoptotic cells were widely distributed in cortex, striatum and hippocampus. Edaravone treatment attenuated neuronal apoptosis as compared with the poisoning group (P < 0.01). Basal expressions of HO-1 and Nrf-2 proteins were found in normal brain tissue. CO poisoning could activate HO-1/Nrf-2 pathway, start oxidative stress response. After the administration of Edaravone, the expression of HO-1 and Nrf-2 significantly increased (P < 0.01). These findings suggest that Edaravone may inhibit apoptosis, activate the Keapl-Nrf/ARE pathway, and thus improve the ultrastructure damage and neurophysiologic changes following acute CO poisoning. © 2014 Wiley Periodicals, Inc.

Ultrastructure of electrophysiologically-characterized synapses formed by serotonergic raphe neurons in culture.

PubMed

Johnson, M D; Yee, A G

1995-08-01

Recent electrophysiological investigations in this laboratory have shown that cultured mesopontine serotonergic neurons from neonatal rats evoke serotonergic and/or glutamatergic responses in themselves and in non-serotonergic neurons. Serotonergic nerve terminals in vivo are heterogeneous with respect to vesicle type, synaptic structure, and the frequency with which they form conventional synaptic contacts, but the functional correlates of this heterogeneity are unclear. We have therefore examined the ultrastructure of electrophysiologically-characterized synapses formed by cultured serotonergic neurons, and have compared the findings with the ultrastructural characteristics of serotonergic synapses reported in vivo. Dissociated rat serotonergic neurons in microcultures were identified by serotonin immunocytochemistry or by uptake of the autofluorescent serotonin analogue 5,7-dihydroxytryptamine, and were subsequently processed for electron microscopy. Unlabeled axon terminals formed numerous synapses on serotonin-immunoreactive somata and dendrites. Serotonin-immunoreactive axon terminals formed synapses on the somata, dendrites and somatodendritic spine-like appendages of serotonergic and non-serotonergic neurons. In microcultures containing a solitary serotonergic neuron that evoked glutamatergic or serotonergic/glutamatergic autaptic responses, both symmetric and asymmetric synapses were present. In addition to large dense core vesicles, individual neurons contained either microcanaliculi and microvesicles, clear round vesicles, or clear pleiomorphic vesicles. For a given cell, however, the subtypes of vesicles present in each axon terminal were similar. Thus, dissociated serotonergic and non-serotonergic raphe neurons formed functional, morphological synapses in culture. A direct examination of both the synaptic physiology and ultrastructure of single cultured serotonergic neurons indicated that these cells released serotonin and glutamate at synapses that were morphologically similar to synapses formed by serotonergic neurons in vivo. The findings also suggested that individual serotonergic neurons differ with respect to synaptic vesicle morphology, and are capable of simultaneously forming symmetric and asymmetric synapses with target cells.

Structural and ultrastructural features of the agouti tongue (Dasyprocta aguti Linnaeus, 1766)

PubMed Central

Ciena, Adriano Polican; Bolina, Cristina de Sousa; de Almeida, Sonia Regina Yokomizo; Rici, Rose Eli Grassi; de Oliveira, Moacir Franco; da da Silva, Marcelo Cavenaghi Pereira; Miglino, Maria Angélica; Watanabe, Ii-sei

2013-01-01

The agouti (Dasyprocta aguti Linnaeus, 1766) is a wild rodent belonging to the family Dasyproctidae that is found throughout Brazil and feeds on fruits and seeds. The aim of the present study was to describe the following features of the tongue of agouti: its morphological structures, the three-dimensional characteristics of the lingual papillae surface, the connective tissue cores (CTCs) and the epithelial cell ultrastructure. Four types of papillae were observed on the dorsal surface of the tongue with a triangular shape: filiform, fungiform, foliate and vallate. Filiform papillae were distributed throughout the tongue surface, and removal of the epithelial surface revealed conical CTCs and multifilaments. Fungiform papillae were observed in the rostral and middle regions, whereas foliate papillae developed in pairs on the lateral margin of the caudal region. Removal of the epithelium in these regions revealed CTCs with parallel laminar conformation. Vallate papillae were arranged in a V-shape in the caudal region, and their CTCs ranged in shape from elongate to ovoid. The ultrastructural components of the dorsal epithelium were the basal, spinous, granular and keratinised layers. A broad area with cytoplasmic projections was identified in the interface region between the lamina propria and the basal layer. Flattened cells with intermediate filaments were observed in the transitional region between spinous and granular layers. The keratinised layer was composed of superimposed epithelial cells where desmosomes and cell-surface microridges were observed. These structural features, including the three-dimensional aspects of the lingual papillae, the CTCs and the epithelial ultrastructure, indicate that when compared with other animals, particularly other rodent species, the morphological features of the tongue of agouti are relatively well developed, especially regarding foliate and vallate papillae. PMID:23701183

Localization of acetylcholine receptors and synaptic ultrastructure at nerve-muscle contacts in culture: dependence on nerve type

PubMed Central

Cohen, MW; Weldon, PR

1980-01-01

In cultures of xenopus myotomal muscle cells and spinal cord (SC) some of the nerve-muscle contacts exhibit a high density of acetylcholine receptors (AchRs [Anderson et al., 1977, J. Physiol. (Lond.). 268:731- 756,757-773]) and synaptic ultrastructure (Weldon and Cohen, 1979, J. Neurocytol. 8:239-259). We have examined whether similarly specialized contacts are established when the muscle cells are cultured with explants of xenopus dorsal root ganglia (DRG) or sympathetic ganglia (SG). The outgrowth from the ganglionic explants contained neuronal and non- neuronal cell processes. Although both types of processes approached within 100 A of muscle cells, synaptic ultrastructure was rarely observed at these contacts. Because patches of postsynaptic ultrastructure also develop on noncontacted muscle cells, the very few examples of contacts with such specializations probably occurred by chance. AChRs were stained with fluroscent α-bungarotoxin. More than 70 percent of the SC-contacted muscle cells exhibited a high receptor density along the path of contact. The corresponding values for DRG- and SG- contacted muscle cells were 10 and 6 percent. Similar values were obtained when the ganlionic and SC explants were cultured together in the same chamber. The few examples of high receptor density at ganglionic-muscle contacts resembled the characteristic receptor patches of noncontacted muscle cells rather than the narrow bands of high receptor density seen at SC-muscle contacts. In addition, more than 90 percent of these ganglionic- contacted muscle cells had receptor patches elsewhere, compared to less than 40 percent for the SC-contacted muscle cells. These findings indicate that the SC neurites possess a specific property which is important for the establishment of synaptically specialized contacts with muscle and that this property is lacking in the DRG and SG neurites. PMID:7400212

Effect of hyperbaric oxygen on lipid peroxidation and visual development in neonatal rats with hypoxia-ischemia brain damage.

PubMed

Chen, Jing; Chen, Yan-Hui; Lv, Hong-Yan; Chen, Li-Ting

2016-07-01

The aim of the present study was to investigate the effect of hyperbaric oxygen (HBO) on lipid peroxidation and visual development in a neonatal rat model of hypoxic-ischemic brain damage (HIBD). The rat models of HIBD were established by delayed uterus dissection and were divided randomly into two groups (10 rats each): HIBD and HBO-treated HIBD (HIBD+HBO) group. Another 20 rats that underwent sham-surgery were also divided randomly into the HBO-treated and control groups. The rats that underwent HBO treatment received HBO (0.02 MPa, 1 h/day) 24 h after the surgery and this continued for 14 days. When rats were 4 weeks old, their flash visual evoked potentials (F-VEPs) were monitored and the ultrastructures of the hippocampus were observed under transmission electron microscope. The levels of superoxide dismutase (SOD) and malonyldialdehyde (MDA) in the brain tissue homogenate were detected by xanthine oxidase and the thiobarbituric acid colorimetric method. Compared with the control group, the ultrastructures of the pyramidal neurons in the hippocampal CA3 area were distorted, the latencies of F-VEPs were prolonged (P<0.01) and the SOD activities were lower while the MDA levels were higher (P<0.01) in the HIBD group. No significant differences in ultrastructure, the latency of F-VEPs or SOD/MDA levels were identified between the HBO-treated HIBD group and the normal control group (P>0.05). HBO enhances antioxidant capacity and reduces the ultrastructural damage induced by hypoxic-ischemia, which may improve synaptic reconstruction and alleviate immature brain damage to promote the habilitation of brain function.

[Nicorandil improves cognitive dysfunction in mice with streptozotocin-induced diabetes].

PubMed

Yan, Wen-Hui; Zhang, Chun-Xi; Xing, Tong; Gong, Xue; Yang, Yu-Xuan; Li, Yi-Nuo; Liu, Xuan; Ayijiang, Jiamaliding; Yu, Ye; Zhang, Meng; Chen, Li-Na

2018-04-20

To observe the protective effects of potassium channel opener nicorandil against cognitive dysfunction in mice with streptozotocin (STZ)-induced diabetes. C57BL/6J mouse models of type 1 diabetes mellitus (T1DM) were established by intraperitoneal injection of STZ and received daily treatment with intragastric administration of nicorandil or saline (model group) for 4 consecutive weeks, with normal C57BL/6J mice serving as control. Fasting blood glucose level was recorded every week and Morris water maze was used to evaluate the cognitive behavior of the mice in the 4th week. At the end of the experiment, the mice were sacrificed to observe the ultrastructural changes in the hippocampus and pancreas under transmission electron microscopy; the contents of glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) in the hippocampus and SOD activity and MDA level in the brain tissue were determined. Compared with the control group, the model group showed significantly increased fasting blood glucose (P<0.001), significantly prolonged escape latency (P<0.05) and increased swimming distance (P<0.01) with ultrastructural damage of pancreatic β cells and in the hippocampus; GIP and GLP-1 contents in the hippocampus (P<0.01) and SOD activity in the brain were significantly decreased (P<0.05) and MDA content was significantly increased in the model group (P<0.05). Compared with the model group, nicorandil treatment did not cause significant changes in fasting blood glucose, but significantly reduced the swimming distance (P<0.05); nicorandil did not improve the ultrastructural changes in pancreatic β cells but obviously improved the ultrastructures of hippocampal neurons and synapses. Nicorandil also significantly increased the contents of GIP and GLP-1 in the hippocampus (P<0.05), enhanced SOD activity (P<0.05) and decreased MDA level (P<0.01) in the brain tissue. Nicorandil improves cognitive dysfunction in mice with STZ-induced diabetes by increasing GIP and GLP-1 contents in the hippocampus and promoting antioxidation to relieve hippocampal injury.

Ultrastructure features of camel cornea--collagen fibril and proteoglycans.

PubMed

Almubrad, Turki; Akhtar, Saeed

2012-01-01

  The uniform distribution of collagen fibrils and proteoglycans maintain the transparency of normal cornea. We describe the ultrastructural features of camel cornea including collagen fibrils and proteoglycans (PGs).   Camel corneas (of 6-, 8-, and 10-month-old animals) were fixed in 2.5% glutaraldehyde containing cuprolinic blue in sodium acetate buffer and processed for electron microscopy. The 'AnalySIS LS Professional' program was used to analyze the collagen fibril diameter.   The camel cornea consists of four layers: the epithelium (227 μm), stroma (388 μm), Descemet's membrane (DM), and endothelium. The epithelium constituted 36% of the camel cornea, whereas corneal stroma constituted 62% of the corneal thickness (629 μm). The PGs in the posterior stroma were significantly larger in number and size compared with the anterior and middle stroma. The collagen fibril diameter was 25 nm and interfibrillar spacing 40 nm. Fibrillar structures are present throughout the DM.   The structure of the camel cornea is very different from human and other animals. The unique structure of the cornea might be an adaptation to help the camel to survive in a hot and dry climate. The camel cornea may also be a good model to study the effect of hot and dry climates on the cornea. © 2011 American College of Veterinary Ophthalmologists.

Ultrastructure of the post-corpus of Zeldia punctata (Cephalobina) for analysis of the evolutionary framework of nematodes related to Caenorhabditis elegans (Rhabditina).

PubMed Central

Zhang, Y C; Baldwin, J G

2000-01-01

The ultrastructure of the post-corpus of Zeldia punctata (Cephalobina) was compared with previous observations of Caenorhabditis elegans (Rhabditina) and Diplenteron sp. (Diplogastrina) with the goal of interpreting the morphological evolution of the feeding structures in the Secernentea. The post-corpus of Z. punctata consists of six marginal, 13 muscle, five gland and seven nerve cells. The most anterior of four layers of muscle cells consists of six mononucleate cells in Z. punctata. The homologous layer in C. elegans and Diplenteron consists of three binucleate cells, suggesting a unique derived character (synapomorphy) shared between the Rhabditina and Diplogastrina. Contrary to Diplenteron sp. where we observed three oesophageal glands, Z. punctata and C. elegans have five oesophageal glands. We question this shared character as reflecting a common evolution between the Cephalobina and Rhabditina, because there are strong arguments for functional (adaptive) convergence of the five glands in these bacterial feeders. Convergence is further suggested by the mosaic distribution of three versus five glands throughout the Nemata; this distribution creates difficulties in establishing character polarity. Although morphological data are often laborious to recover and interpret, we nevertheless view 'reciprocal illumination' between molecular and morphological characters as the most promising and robust process for reconstructing the evolution of the Secernentea and its feeding structures. PMID:10902689

A new approach in the management of urothelial tumors using GM-CSF on marker lesions: an ultrastructural and immunohistochemical study on the macrophage population in bladder mucosa.

PubMed

Stravoravdi, P; Toliou, T; Kirtsis, P; Natsis, K; Konstandinidis, E; Barich, A; Gigis, P; Dimitriadis, K

1999-03-01

Our purpose was to investigate a new therapeutic model, GM-CSF-targeted immunomodulation on transitional cell carcinoma (TCC) marker lesions and to evaluate the immunologic response of the bladder mucosa. Eleven patients with pTa or pT1 bladder cancer were eligible for the study. All lesions were removed by transurethral resection (TUR) except for a marker lesion. All patients received 8 weekly instillations of 300 microg of GM-CSF, after which cystoscopy with bladder biopsies +/- TUR was repeated on adjacent urothelium or tumor or both. Paraffin-embedded sections were immunohistochemically stained with CD68, which labels monocytes and macrophages. The CD68+ cell population was evaluated as 1+ to 3+. Comparable specimens were routinely processed for ultrastructural analysis. Complete response was observed in 6 patients (55%), persistent tumor occurred in 4 patients (approximately 36.4%), and 1 patient (8.6%) showed recurrence. Immunohistochemically, an at least twofold increase in the number of the CD68+ cells was observed in all responders. Submicroscopically, migration of macrophages to the surface layer occurred. Macrophages showed an extensive lysosomal system and pseudopodia. This study indicates that the prophylactic treatment of TCC with GM-CSF may induce immunomodulatory effects on macrophage activities, which could be associated with the clinical evolution of the disease.

Melatonin mitigates neomycin-induced hair cell injury in zebrafish.

PubMed

Oh, Kyoung Ho; Rah, Yoon Chan; Hwang, Kyu Ho; Lee, Seung Hoon; Kwon, Soon Young; Cha, Jae Hyung; Choi, June

2017-10-01

Ototoxicity due to medications, such as aminoglycosides, is irreversible, and free radicals in the inner ear are assumed to play a major role. Because melatonin has an antioxidant property, we hypothesize that it might mitigate hair cell injury by aminoglycosides. The objective of this study was to evaluate whether melatonin has an alleviative effect on neomycin-induced hair cell injury in zebrafish (Danio rerio). Various concentrations of melatonin were administered to 5-day post-fertilization zebrafish treated with 125 μM neomycin for 1 h. Surviving hair cells within four neuromasts were compared with that of a control group. Apoptosis was assessed via terminal deoxynucleotidyl transferase dUTP nick-end labeling assay. The changes of ultrastructure were confirmed using a scanning electron microscope. Melatonin alleviated neomycin-induced hair cell injury in neuromasts (neomycin + melatonin 100 μM: 13.88 ± 0.91 cells, neomycin only: 7.85 ± 0.90 cells; n = 10, p < 0.05) and reduced neomycin-induced apoptosis in the TUNEL assay. In ultrastructural analysis, hair cells within the neuromasts in zebrafish were preserved exposed to 125 μM neomycin and 100 μM melatonin for 1 h in SEM findings. Melatonin is effective in alleviating aminoglycoside-induced hair cell injury in zebrafish. The results of this study demonstrated that melatonin has the potential to reduce apoptosis induced by aminoglycosides in zebrafish.

CNGA3 deficiency affects cone synaptic terminal structure and function and leads to secondary rod dysfunction and degeneration.

PubMed

Xu, Jianhua; Morris, Lynsie M; Michalakis, Stylianos; Biel, Martin; Fliesler, Steven J; Sherry, David M; Ding, Xi-Qin

2012-03-01

To investigate rod function and survival after cone dysfunction and degeneration in a mouse model of cone cyclic nucleotide-gated (CNG) channel deficiency. Rod function and survival in mice with cone CNG channel subunit CNGA3 deficiency (CNGA3-/- mice) were evaluated by electroretinographic (ERG), morphometric, and Western blot analyses. The arrangement, integrity, and ultrastructure of photoreceptor terminals were investigated by immunohistochemistry and electron microscopy. The authors found loss of cone function and cone death accompanied by impairment of rods and rod-driven signaling in CNGA3-/- mice. Scotopic ERG b-wave amplitudes were reduced by 15% at 1 month, 30% at 6 months, and 40% at 9 months and older, while scotopic a-wave amplitudes were decreased by 20% at 9 months, compared with ERGs of age-matched wild-type mice. Outer nuclear layer thickness in CNGA3-/- retina was reduced by 15% at 12 months compared with age-matched wild-type controls. This was accompanied by a 30%-40% reduction in expression of rod-specific proteins, including rhodopsin, rod transducin α-subunit, and glutamic acid-rich protein (GARP). Cone terminals in the CNGA3-/- retina showed a progressive loss of neurochemical and ultrastructural integrity. Abnormalities were observed as early as 1 month. Disorganized rod terminal ultrastructure was noted by 12 months. These findings demonstrate secondary rod impairment and degeneration after cone degeneration in mice with cone CNG channel deficiency. Loss of cone phototransduction accompanies the compromised integrity of cone terminals. With time, rod synaptic structure, function, and viability also become compromised.

ULTRASTRUCTURAL STUDY OF LESIONS IN GILLS OF A MARINE SHRIMP EXPOSED TO CADMIUM

EPA Science Inventory

Pathologic black gills of pink shrimp, Penaeus duorarum, exposed to 763 micrograms/l of cadmium chloride for 15 days were studied with transmission electron microscopy and were compared with normal gills of control pink shrimp. Local as well as extensive areas of cell death and n...

An ultrastructural study of calcitonin gene-related peptide-immunoreactive nerve fibers innervating the rat posterior longitudinal ligament. A morphologic basis for their possible efferent actions.

PubMed

Imai, S; Konttinen, Y T; Tokunaga, Y; Maeda, T; Hukuda, S; Santavirta, S

1997-09-01

The present study investigated ultrastructural characteristics of calcitonin gene-related peptide-immunoreactive nerve fibers in the posterior longitudinal ligament of the rat lumbar spine. To provide a morphologic basis for assessment of the afferent and, in particular, efferent functions of calcitonin gene-related peptide immunoreactive nerves in the posterior longitudinal ligament and their eventual role in degenerative spondylarthropathies and low back pain. Previous studies using light-microscopic localization of sensory neuronal markers such as calcitonin gene-related peptide have reported the presence of sensory fibers in the supporting structures of the vertebral column. Meanwhile, accumulating research data have suggested efferent properties for calcitonin gene-related peptide, i.e., a trophic action that alters the intrinsic properties of target cells not through transient action of synaptic transmission, but through long-lasting signal transmission by the secreted neuropeptides. To verify such trophic, paracrine actions of the calcitonin gene-related peptide-containing fibers in the posterior longitudinal ligament, however, ultrastructural details of the terminals and their spatial relationship to their eventual target structures have to be elucidated. Rat posterior longitudinal ligaments were stained immunohistochemically for calcitonin gene-related peptide. Light-microscopic analysis of the semithin sections facilitated subsequent electron microscopy of specific sites of the posterior longitudinal ligament to determine ultrastructural details and nerve fiber-target relationships. The rat lumbar posterior longitudinal ligament was found to be innervated by two distinctive calcitonin gene-related peptide immunoreactive nerve networks. In immunoelectronmicroscopy, the fibers of the deep network had numerous free nerve endings, whereas those of the superficial network showed spatial associations with other non-calcitonin gene-related peptide immunoreactive components of the network. In both systems, naked axons not covered by the Schwann cells made close spatial contact with smooth muscle cells: of blood vessels and resident posterior longitudinal ligament fibroblasts. The ultrastructural characteristics of the innervation of the rat posterior longitudinal ligament would be compatible not only with a nociceptive function, but also with neuromodulatory, vasoregulatory, and trophic functions, as has already been established in some visceral organs.

The Effect of Early Intervention and Rehabilitation in the Expression of Aquaporin-4; and Ultrastructure Changes on Rat's Offspring's Damaged Brain Caused by Intrauterine Infection

PubMed Central

Rajesh, Kumar; Xiangying, Kong

2015-01-01

Objective To study the effect of early intervention and rehabilitation in the expression of aquaporin-4 and ultrastructure changes on cerebral palsy pups model induced by intrauterine infection. Methods 20 pregnant Wistar rats were consecutively injected with lipopolysaccharide intraperitoneally. 60 Pups born from lipopolysaccharide group were randomly divided into intervention group (n=30) and non-intervention group (n=30); intervention group further divided into early intervention and rehabilitation group (n=10), acupuncture group (n=10) and consolidate group (n=10). Another 5 pregnant rats were injected with normal saline intraperitoneally; 30 pups born from the normal saline group were taken as control group. The intervention group received early intervention, rehabilitation and acupuncture treatment. The motor functions of all pups were assessed via suspension test and modified BBB locomotor score. Aquaporin-4 expression in brain tissue was studied through immunohistochemical and western-blot analysis. Ultrastructure changes in damaged brain and control group were studied electron-microscopically. Results The scores of suspension test and modified BBB locomotor test were significantly higher in the control group than the intervention and non intervention group (p<0.01); higher in the intervention group than the non-intervention group (p<0.01). The expression of Aquaporin-4 was lower in intervention and non intervention group than in the control group (p<0.01); also lower in non-intervention group than the intervention group (p<0.01). Marked changes were observed in ultrastructure of cortex and hippocampus CAI in brain damaged group. Conclusion Early intervention and rehabilitation training can improve the motor function in offspring with brain injury and reduce the expression of aquaporin-4 in damaged brain. PMID:26279808

Animal models for treatment of unresectable liver tumours: a histopathologic and ultra-structural study of cellular toxic changes after electrochemical treatment in rat and dog liver.

PubMed

von Euler, Henrik; Olsson, Jerker M; Hultenby, Kjell; Thörne, Anders; Lagerstedt, Anne-Sofie

2003-04-01

Electrochemical treatment (EChT) has been taken under serious consideration as being one of several techniques for local treatment of malignancies. The advantage of EChT is the minimal invasive approach and the absence of serious side effects. Macroscopic, histopathological and ultra-structural findings in liver following a four-electrode configuration (dog) and a two-electrode EChT design (dog and rat) were studied. 30 female Sprague-Dawley rats and four female beagle dogs were studied with EChT using Platinum:Iridium electrodes and the delivered dose was 5, 10 or 90 C (As). After EChT, the animals were euthanized. The distribution of the lesions was predictable, irrespective of dose and electrode configuration. Destruction volumes were found to fit into a logarithmic curve (dose-response). Histopathological examination confirmed a spherical (rat) and cylindrical/ellipsoidal (dog) lesion. The type of necrosis differed due to electrode polarity. Ultra-structural analysis showed distinct features of cell damage depending on the distance from the electrode. Histopathological and ultra-structural examination demonstrated that the liver tissue close to the border of the lesion displayed a normal morphology. The in vivo dose-planning model is reliable, even in species with larger tissue mass such as dogs. A multi-electrode EChT-design could obtain predictable lesions. The cellular toxicity following EChT is clearly identified and varies with the distance from the electrode and polarity. The distinct border between the lesion and normal tissue suggests that EChT in a clinical setting for the treatment of liver tumours can give a reliable destruction margin.

Effects of Electroacupuncture on Interstitial Cells of Cajal (ICC) Ultrastructure and Connexin 43 Protein Expression in the Gastrointestinal Tract of Functional Dyspepsia (FD) Rats.

PubMed

Zhang, Guoshan; Xie, Shen; Hu, Wei; Liu, Yuer; Liu, Mailan; Liu, Mi; Chang, Xiaorong

2016-06-14

BACKGROUND Gastrointestinal motility disorder is the main clinical manifestation in functional dyspepsia (FD) patients. Electroacupuncture is effective in improving gastrointestinal motility disorder in FD; however, the underlying mechanism remains unclear. It has been demonstrated that interstitial cells of Cajal (ICC) are pacemaker cells in the gastrointestinal tract, and the pacemaker potential is transmitted to nearby cells through gap junctions between ICC or ICC and the smooth muscle. Therefore, this study aimed to assess the effects of electroacupuncture on ICC ultrastructure and expression of the gap junction protein connexin 43 (Cx43) in FD rats. MATERIAL AND METHODS The animals were randomized into 3 groups: control, model, and electroacupuncture. Electroacupuncture was applied at Zusanli (ST36) in the electroacupuncture group daily for 10 days, while no electroacupuncture was applied to model group animals. RESULTS Ultrastructure of ICC recovered normally in gastric antrum and small intestine specimens was improved, with Cx43 expression levels in these tissues significantly increased in the electroacupuncture group compared with the model group. CONCLUSIONS These findings indicated that electroacupuncture is effective in alleviating ICC damage and reduces Cx43 levels in FD rats, and suggest that ICC and Cx43 are involved in electroacupuncture treatment in rats with FD to improve gastrointestinal motility disorders.

Isolation, in vitro culture, ultrastructure study, and characterization by lectin-agglutination tests of Phytomonas isolated from tomatoes (Lycopersicon esculentum) and cherimoyas (Anona cherimolia) in southeastern Spain.

PubMed

Sanchez-Moreno, M; Fernandez-Becerra, C; Mascaro, C; Rosales, M J; Dollet, M; Osuna, A

1995-01-01

Plants of Lycopersicon esculentum (grown in greenhouses) and Anona cherimolia cultivated in southeastern Spain were examined for the presence of trypanosomatid flagellates. Kinetoplastid protozoa were found in the fruits but not in the phloem or other plant tissues. Parasites were detected from the onset of fruiting. Isolates were detected from the onset of fruiting. Isolates were adapted to in vitro culturing in monophase media. The form and the structural organization was studied by scanning and transmission electron microscopy. The parasites showed an ultrastructural pattern similar to that of other species of the genus Phytomonas. In tomatoes experimentally inoculated with flagellates cultivated in vitro, we observed that the parasites did not lose their infectious capacity. Three strains of trypanosomatids of the genus Phytomonas, isolated from different species of Euphorbia (E. characias and E. hyssopifolia) and from Cocos nucifera, were compared with our isolates by lectin-agglutination tests. Our isolates were different from the two strains isolated from Euphorbia, but with this technique we could not differentiate our isolates from those of the coconut, nor could we differentiate between the isolates, their ultrastructural similarity together with their similar behavior in the lectin-agglutination test suggesting that these isolates have a common origin.

[Chloroplast ultrastructure and photosynthetic characteristics of five kinds of dandelion (Taraxacum) leaves in northeast China].

PubMed

Ning, Wei; Wu, Jie; Zhao, Ting; Zhao, Xin; Li, Tianlai

2012-05-01

The paper adopted the JEM-100CX II transmission electron microscope to observe chloroplast ultrastructure of five kinds of dandelion (Taraxacum) leaves in northeast, and the LI-6400 portable photosynthesis system was used to compare the chlorophyll fluorescence and the photosynthesis characteristics of five kinds of dandelions in Northeast China. Chloroplast ultrastructure showed: in the five kinds of dandelion, larger chloroplast, grana with more layers, regular thylakoid, without starch grains and so on, these chloroplasts characteristics decided to bigger photosynthetic rate. The five kinds of dandelion P(n) exhibited a "double peak" diurnal curve: stomatal limitation is the main adjustment factors for the midday depression phenomenon. The P(n),G(s),C(i) content of T. mongolicum are the highest, and T. asiaticum are the lowest among them. The relation between P(n) and G(s),C(i) is direct ratio, P(n) and T(r) is in an inverse proportion among the five kinds of dandelion. In addition, P(n) is positively correlated with Chla, Chlb, and the relationship with Chlb is bigger. The paper demonstrates the Mongolian dandelion photosynthetic efficiency is the highest, it is an higher photosynthetic efficiency dandelion,it provide theoretical basis for assessment and use of the resource of dandelion.

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

PubMed

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.

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

PubMed

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 Correlates of the Protection Afforded by Niacinamide against Sulfur Mustard-Induced Cytotoxicity of Human Lymphocytes in Vitro

DTIC Science & Technology

1988-12-01

Page No. 1. Light Microscopy of Human Skin Grafted onto Congenitally Athymic Nude Mice .................. 4 2. Ultrastructural Changes Produced by HD...laboratory published a report on the ultrastructure of the pathogenesis of blister formation following exposure to sulfur mustard of human- skin grafted to...candidate prophylactic compounds such as niacirnamide. By way of review, hD-induced pathology of human skin grafted onto congenitally athymic nude mice was

Tumor formation of prostate cancer cells influenced by stromal cells from the transitional or peripheral zones of the normal prostate

PubMed Central

Zhao, Fu-Jun; Han, Bang-Min; Yu, Sheng-Qiang; Xia, Shu-Jie

2009-01-01

This study was designed to investigate the different involvements of prostatic stromal cells from the normal transitional zone (TZ) or peripheral zone (PZ) in the carcinogenesis of prostate cancer (PCa) epithelial cells (PC-3) in vitro and in vivo co-culture models. Ultra-structures and gene expression profiles of primary cultures of human prostatic stromal cells from the normal TZ or PZ were analyzed by electron microscopy and microarray analysis. In vitro and in vivo co-culture models composed of normal TZ or PZ stromal cells and human PCa PC-3 cells were established. We assessed tumor growth and weight in the in vivo nude mice model. There are morphological and ultra-structural differences in stromal cells from TZ and PZ of the normal prostate. In all, 514 differentially expressed genes were selected by microarray analysis; 483 genes were more highly expressed in stromal cells from TZ and 31 were more highly expressed in those from PZ. Co-culture with PZ stromal cells and transforming growth factor-β1 (TGF-β1) increased the tumor growth of PC-3 cells in vitro and in vivo, as well as Bcl-2 expression. On the other hand, stromal cells of TZ suppressed PC-3 cell tumor growth in the mouse model. We conclude that ultra-structures and gene expression differ between the stromal cells from TZ or PZ of the normal prostate, and stroma–epithelium interactions from TZ or PZ might be responsible for the distinct zonal localization of prostate tumor formation. PMID:19122679

Ultrastructure and elemental analysis of Hypoxis hemerocallidea: a multipurpose medicinal plant.

PubMed

Afolayan, Anthony J; Otunola, Gloria A

2014-01-01

Herbal medicine is a popular means of medical management in some parts of the world especially in Africa. Hypoxis hemerocallidea Fisch.C.A.Mey. & Avé-Lall, also known as African potato of the Hypoxidaecae family, is one of the medicinal plants that have enjoyed long usage as an herbal medicine in South Africa. In this study, the morphology and elemental constituents of H. hemerocallidea leaf was investigated to correlate the functional role of the ultrastructure in the production of therapeutic compounds. Fresh leaves of H. hemerocallidea were prepared for analysis using standard methods. The ultrastructure and crystal deposits of the plant were assessed using scanning electron microscopy (SEM), and energy dispersive x-ray (EDX). It was observed that the leaves were characterised by multicelullar glandular and non glandular trichomes which are sparsely distributed over the entire surfaces. The glandular trichomes (GTs) in H. hemerocallidea leaf have boulbous heads which are probably filled with secretions, while the non glandular trichomes were long, fibrous and sparse. EDX-SEM of Hypoxis hemerocallidea leaf revealed that carbon, oxygen, nitrogen and silicon are the major components of the deposits, while other elements such as iron, sulphur, sodium, calcium, magnesium, potassium, manganese, iodine, chromium and iodine were present in small but variable amounts. The presence of these elements which are crucial to maintaining good health, in addition to other bioactive constituents might be accountable for the multipurpose therapeutic uses of Hypoxis hemerocallidea in the treatment of cancers, HIV/AIDS related diseases, urinary tract infections, cardiovascular disorders, diabetes and other chronic ailments of humans.

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

PubMed Central

Elkhatib, Walid F.

2016-01-01

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. PMID:26954570

A rare case of respiratory disorders associated with two autosomal recessive diseases and male infertility.

PubMed

Mendeluk, Gabriela Ruth; Costa, Sergio López; Scigliano, Sergio; Menga, Guillermo; Demiceu, Sergio; Palaoro, Luis Alberto

2013-01-01

The study of nasal ciliary beat frequency (CBF) and ultrastructure may contribute to the understanding of pathognomonic cases of male infertility associated with defects in sperm motility. This study was designed to report a particular case of male infertility, characterized by the association of two respiratory autosomal recessive genetic diseases (alpha-1-antitrypsin deficiency [AAT-D] and primary ciliary dyskinesia [PCD]). A 39-year-old patient with complete sperm immotility, AAT-D, and bronchiectasis was studied in the Laboratory of Male Fertility, the Department of Urology, the Respiratory Center of a Pediatric Hospital, and in the Department of Clinical Medicine of a Rehabilitation Respiratory Hospital. Family history, physical examination, hormonal analysis, microbial assays, semen analysis, nasal ciliary function, and structure study by digital high-speed video photography and transmission electron microscopy are described. A noninvasive nasal biopsy to retrieve ciliated epithelium lining the inferior surface of the inferior nasal turbinates was performed and CBF was determined. Beat pattern was slightly curved and rigid, not wide, and metacronic in all the observed fields analyzed. CBF was 8.2 Hz in average (reference value, 10-15 Hz) Ultrastructural assay revealed absence of the inner dynein arms in 97% of the cilia observed. The final infertility accurate diagnosis was achieved by the study of nasal CBF and ultrastructure contributing to the patient health management and genetic counseling while deciding fatherhood. Beyond this particular case, the present report may open a new field of studies in male infertility, mainly in cases of asthenozoospermia.

A rare case of respiratory disorders associated with two autosomal recessive diseases and male infertility

PubMed Central

Costa, Sergio López; Scigliano, Sergio; Menga, Guillermo; Demiceu, Sergio; Palaoro, Luis Alberto

2013-01-01

The study of nasal ciliary beat frequency (CBF) and ultrastructure may contribute to the understanding of pathognomonic cases of male infertility associated with defects in sperm motility. This study was designed to report a particular case of male infertility, characterized by the association of two respiratory autosomal recessive genetic diseases (alpha-1-antitrypsin deficiency [AAT-D] and primary ciliary dyskinesia [PCD]). A 39-year-old patient with complete sperm immotility, AAT-D, and bronchiectasis was studied in the Laboratory of Male Fertility, the Department of Urology, the Respiratory Center of a Pediatric Hospital, and in the Department of Clinical Medicine of a Rehabilitation Respiratory Hospital. Family history, physical examination, hormonal analysis, microbial assays, semen analysis, nasal ciliary function, and structure study by digital high-speed video photography and transmission electron microscopy are described. A noninvasive nasal biopsy to retrieve ciliated epithelium lining the inferior surface of the inferior nasal turbinates was performed and CBF was determined. Beat pattern was slightly curved and rigid, not wide, and metacronic in all the observed fields analyzed. CBF was 8.2 Hz in average (reference value, 10–15 Hz) Ultrastructural assay revealed absence of the inner dynein arms in 97% of the cilia observed. The final infertility accurate diagnosis was achieved by the study of nasal CBF and ultrastructure contributing to the patient health management and genetic counseling while deciding fatherhood. Beyond this particular case, the present report may open a new field of studies in male infertility, mainly in cases of asthenozoospermia. PMID:23772318

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

PubMed

Wasfi, Reham; Elkhatib, Walid F; Khairalla, Ahmed S

2016-01-01

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.

Mechanical properties and ultrastructural characteristics of a glass fiber-reinforced composite.

PubMed

García Barbero, Alvaro Enrique; Vera González, Vicente; García Barbero, Ernesto; Aliaga Vera, Ignacio

2015-06-01

To examine the ultrastructural characteristics of a fiber-reinforced composite (FRC) and its behavior in vitro as a framework for fixed partial dentures (FPDs). A total of 40 specimens were prepared using extracted teeth fixed in methacrylate blocks as supports for the FPD, then the specimens were divided into four groups depending on whether a retaining box was used to fix the FPD to the support teeth, and on whether a composite pontic was assembled on top of the fibers. Fracture testing was performed in a universal testing machine (1 mm/minute). Fracture strength values and failure types were statistically compared for each group. Using retaining boxes did not improve the mechanical behavior of the restorative system. The weakest element of the system was the composite tooth constructed on top of the FRC.

Assessment of nerve ultrastructure by fibre-optic confocal microscopy.

PubMed

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.

Tripartite differentiation (squamous, glandular, and melanocytic) of a primary cutaneous neuroendocrine carcinoma. An immunocytochemical and ultrastructural study.

PubMed

Isimbaldi, G; Sironi, M; Taccagni, G; Declich, P; Dell'Antonio, A; Galli, C

1993-06-01

We report a case of primary cutaneous neuroendocrine carcinoma (PCNEC) with squamous, glandular, and melanocytic differentiation and associated Bowen disease. The paranuclear globular positivity of low-molecular-weight cytokeratins agrees with the ultrastructural observations of paranuclear fibrous bodies in the small neuroendocrine cells, while the diffuse cytoplasmic positivity corresponds to the sparse intermediate filaments in large cells with squamous differentiation. "Transitional forms" are characterized by both diffuse and globular cytoplasmic positivity for cytokeratins and by the ultrastructural evidence of neuroendocrine and squamous features. Therefore the ultrastructural demonstration of intracytoplasmic tonofibrils and tonofilaments, intercellular glandular lumina, lined by well-formed microvilli, and immature premelanosomes in the neurosecretory cells supports the proposed tripartite differentiation of neuroendocrine cells of this case of PCNEC.

Metal resistant rhizobia and ultrastructure of Anthyllis vulneraria nodules from zinc and lead contaminated tailing in Poland.

PubMed

Sujkowska-Rybkowska, Marzena; Ważny, Rafał

2018-06-07

This present paper studies the response of Anthyllis vulneraria-Rhizobium symbiosis to heavy metal stress. The symbiotic rhizobium bacteria isolated from root nodules of A. vulneraria from zinc and lead wastes were examined in this project. Light microscopy (LM) and transmission electron microscopy (TEM) were used to analyze the nodule anatomy and ultrastructure and conduct a comparison with nonmetal-treated nodules. 16S ribosomal DNA sequence analysis of bacteria isolated from metal-treated nodules revealed the presence of Rhizobium metallidurans and Bradyrhizobium sp. In regard to heavy metal resistance/tolerance, a similar tolerance to Pb was shown by both strains, and a high tolerance to Zn and a lower tolerance to Cd and Cu by R. metallidurans, whereas a high tolerance to Cd and Cu and a lower tolerance to Zn by Bradyrhizobium were found. The nodules of Anthyllis from metal-polluted tailing sites were identified as the typical determinate type of nodules. Observed under TEM microscopy changes in nodules ultrastructure like: (1) wall thickening; (2) infection thread reduction; (3) vacuole shrinkage; (4) synthesis of phenolics in vacuoles; (5) various differentiation of bacteroids and (6) simultaneous symbiosis with arbuscular mycorrhiza fungi could be considered as a form of the A.vulneraria-Rhizobium symbiosis adaptation to metal stress.

Isoflurane anesthesia results in reversible ultrastructure and occludin tight junction protein expression changes in hippocampal blood-brain barrier in aged rats.

PubMed

Cao, Yiyun; Ni, Cheng; Li, Zhengqian; Li, Lunxu; Liu, Yajie; Wang, Chunyi; Zhong, Yanfeng; Cui, Dehua; Guo, Xiangyang

2015-02-05

The underlying mechanism of isoflurane-induced cognitive dysfunction in older individuals is unknown. In this study, the effects of isoflurane exposure on the hippocampal blood-brain barrier (BBB) in aged rats were investigated because it was previously shown that BBB disruption involves in cognitive dysfunction. Twenty-month-old rats randomly received 1.5% isoflurane or vehicle gas as control. Hippocampal BBB ultrastructure was analyzed by transmission electron microscopy and expression of tight junction proteins was measured by western blot analysis. BBB permeability was detected with sodium fluorescein extravasation and further confirmed by immunoglobulin G immunohistochemistry. Spatial learning and memory were assessed by the Morris water maze test. Isoflurane anesthesia resulted in reversible time-dependent BBB ultrastructure morphological damage and significant decreases in expression of the tight junction proteins occludin, which contributed to sodium fluorescein and IgG leakage. Rats with isoflurane exposure also showed significant cognitive deficits in the Morris water maze test. This in vivo data indicate that occludin down-regulation may be one of the mediators of isoflurane-induced hippocampus BBB disruption, and may contribute to hippocampus-dependent cognitive impairment after isoflurane exposure in aged rats. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Osseointegration of zirconia implants: an SEM observation of the bone-implant interface.

PubMed

Depprich, Rita; Zipprich, Holger; Ommerborn, Michelle; Mahn, Eduardo; Lammers, Lydia; Handschel, Jörg; Naujoks, Christian; Wiesmann, Hans-Peter; Kübler, Norbert R; Meyer, Ulrich

2008-11-06

The successful use of zirconia ceramics in orthopedic surgery led to a demand for dental zirconium-based implant systems. Because of its excellent biomechanical characteristics, biocompatibility, and bright tooth-like color, zirconia (zirconium dioxide, ZrO2) has the potential to become a substitute for titanium as dental implant material. The present study aimed at investigating the osseointegration of zirconia implants with modified ablative surface at an ultrastructural level. A total of 24 zirconia implants with modified ablative surfaces and 24 titanium implants all of similar shape and surface structure were inserted into the tibia of 12 Göttinger minipigs. Block biopsies were harvested 1 week, 4 weeks or 12 weeks (four animals each) after surgery. Scanning electron microscopy (SEM) analysis was performed at the bone implant interface. Remarkable bone attachment was already seen after 1 week which increased further to intimate bone contact after 4 weeks, observed on both zirconia and titanium implant surfaces. After 12 weeks, osseointegration without interposition of an interfacial layer was detected. At the ultrastructural level, there was no obvious difference between the osseointegration of zirconia implants with modified ablative surfaces and titanium implants with a similar surface topography. The results of this study indicate similar osseointegration of zirconia and titanium implants at the ultrastructural level.

Histology and ultrastructure of transitional changes in skin morphology in the juvenile and adult four-striped mouse (Rhabdomys pumilio).

PubMed

Stewart, Eranée; Ajao, Moyosore Salihu; Ihunwo, Amadi Ogonda

2013-01-01

The four-striped mouse has a grey to brown coloured coat with four characteristic dark stripes interspersed with three lighter stripes running along its back. The histological differences in the skin of the juvenile and adult mouse were investigated by Haematoxylin and Eosin and Masson Trichrome staining, while melanocytes in the skin were studied through melanin-specific Ferro-ferricyanide staining. The ultrastructure of the juvenile skin, hair follicles, and melanocytes was also explored. In both the juvenile and adult four-striped mouse, pigment-containing cells were observed in the dermis and were homogeneously dispersed throughout this layer. Apart from these cells, the histology of the skin of the adult four-striped mouse was similar to normal mammalian skin. In the juvenile four-striped mouse, abundant hair follicles of varying sizes were observed in the dermis and hypodermis, while hair follicles of similar size were only present in the dermis of adult four-striped mouse. Ultrastructural analysis of juvenile hair follicles revealed that the arrangement and differentiation of cellular layers were typical of a mammal. This study therefore provides unique transition pattern in the four-striped mouse skin morphology different from the textbook description of the normal mammalian skin.

Apigenin induced apoptosis in esophageal carcinoma cells by destruction membrane structures.

PubMed

Zhu, Haiyan; Jin, Hua; Pi, Jiang; Bai, Haihua; Yang, Fen; Wu, Chaomin; Jiang, Jinhuan; Cai, Jiye

2016-07-01

Apigenin has shown to have killing effects on some kinds of solid tumor cells. However, the changes in cell membrane induced by apigenin on subcellular- or nanometer-level were still unclear. In this work, human esophageal cancer cells (EC9706 and KYSE150 cells) were employed as cell model to detect the cytotoxicity of apigenin, including cell growth inhibition, apoptosis induction, membrane toxicity, etc. MTT assay showed that apigenin could remarkably inhibit the growth and proliferation in both types of cells. Annexin V/PI-based flow cytometry analysis showed that the cytotoxic effects of apigenin in KYSE150 cells were mainly through early apoptosis induction, while in EC9706 cells, necrosis, and apoptosis were both involved in cell death. The morphological and ultrastructural properties induced by apigenin were investigated at single cellular- or nanometer-level using atomic force microscopy (AFM). Additionally, lactate dehydrogenase (LDH) leakage was measured to assess the changes in membrane permeability. The results indicated that apigenin increased the membrane permeability and caused leakage of LDH, which was consistent with damages on membrane ultrastructure detected by AFM. Therefore, membrane toxicity, including membrane ultrastructure damages and enhanced membrane permeability, played vital roles in apigenin induced human esophageal cancer cell apoptosis. SCANNING 38:322-328, 2016. © 2015 Wiley Periodicals, Inc. © Wiley Periodicals, Inc.

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

PubMed

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.

Human immunodeficiency virus-infected macrophages produce soluble factors that cause histological and neurochemical alterations in cultured human brains.

PubMed Central

Pulliam, L; Herndier, B G; Tang, N M; McGrath, M S

1991-01-01

We wanted to establish an in vitro human model for AIDS-associated dementia and pursue the hypothesis that this disease process may be a result of soluble factors produced by HIV-infected macrophages. Human brain aggregates were prepared from nine different brain specimens, and were treated with supernatants from in vitro HIV-infected macrophages (SI), uninfected macrophages (SU), infected T cells, or macrophage-conditioned media from four AIDS patients. Seven of nine treated brains exposed to SI showed peripheral rarefaction after 1 wk of incubation that by ultrastructural analysis showed cytoplasmic vacuolation. Aggregates from two of three brain cultures treated with SI for 3 wk became smaller, an approximately 50% decrease in size. The degree of apparent toxicity in brains exposed to patient-derived macrophage supernatants paralleled the proportion of macrophages found to be expressing HIV p24. Ultrastructural abnormalities were not observed in brains treated with supernatants from HIV-infected T cells, uninfected macrophages, or LPS-activated macrophages. Levels of five neurotransmitter amino acids were decreased in comparison to the structural amino acid leucine. These findings suggest that HIV-infected macrophages, infected both in vitro as well as derived from AIDS patients' peripheral blood, produce factors that cause reproducible histochemical, ultrastructural, and functional abnormalities in human brain aggregates. Images PMID:1671392

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

PubMed

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.

Fibrin chain cross-linking, fibrinolysis, and in vivo sealing efficacy of differently structured fibrin sealants.

PubMed

Hedrich, Hans Christian; Simunek, Manuela; Reisinger, Sonja; Ferguson, James; Gulle, Heinz; Goppelt, Andreas; Redl, Heinz

2012-08-01

In this study, we compared the sealing characteristics and efficacy of a fibrin sealant with reduced plasminogen (FS-rplg) and a fibrin sealant with aprotinin as a fibrinolysis inhibitor (FS-apr). The relevant sealing characteristics including clot structure, fibrin chain cross-linking, and clot lysis were tested in the laboratory. The sealing efficacy was then investigated in a follow-up animal model to determine differences in the in vivo sealing properties. A total of 46 animals were available for the final analysis with 23 animals in each treatment arm. In conclusion, we saw differences in vitro between FS-rplg and FS-apr in ultrastructure and α-chain cross-linking rates as well as in the rate of fibrinolysis. These differences may explain the significantly enhanced sealing efficacy in FS-apr compared to FS-rplg shown in vivo in a rabbit intestinal model. Copyright © 2012 Wiley Periodicals, Inc.

Finite cell lines of turkey sperm storage tubule cells: ultrastructure and protein analysis

USDA-ARS?s Scientific Manuscript database

Cell lines of turkey sperm storage tubule (SST) epithelial cells were established. Turkey SSTs were dissected from freshly obtained uterovaginal junction (UVJ) tissue and placed in explants culture on various substrates and media. Primary cultures of SST epithelium only survived and grew from SST ex...

Ultrastructure of meristem and root cap of pea seedlings under spaceflight conditions

NASA Technical Reports Server (NTRS)

Sytnyk, K. M.; Kordyum, E. L.; Bilyavska, N. O.; Tarasenko, V. O.

1983-01-01

Data of electron microscopic analysis of meristem and root cap of pea seedlings grown aboard the Salyut-6 orbital research station in the Oazis apparatus and in the laboratory are presented. The main morphological and anatomical characteristics of the test and control plants are shown to be similar. At the same time, some differences are found in the structural and functional organization of the experimental cells as compared to the controls. They concern first of all the plastic apparatus, mitochondria and Golgi apparatus. It is assumed that cell function for certain periods of weightlessness on the whole ensures execution of the cytodifferentiation programs genetically determined on the Earth. Biochemical and physiological processes vary rather markedly due to lack of initially rigorous determination.

Morphological and molecular analysis calls for a reappraisal of the red rain cells of Kerala.

PubMed

Gangappa, Rajkumar; Burchell, Mark J; Hogg, Stuart I

2014-02-01

Early studies on the coloured particles that fell as red rain over southern India identified them as unicellular eukaryotes such as members of the red algae or fungi; however, the results of the present investigation are not consistent with this designation. Using transmission electron microscopy, we have demonstrated significant differences in the ultrastructure when compared with representative species from these other groups. Most notably, the red rain cells show no evidence of typical eukaryotic internal structures such as mitochondria or endoplasmic reticulum. Furthermore, comparisons based on elemental composition using energy-dispersive X-ray analysis, as well as Raman spectral signatures demonstrate significant dissimilarities in their molecular composition. The identity and origins of the red rain cells remain an enigma; however, our findings are more consistent with an unidentified prokaryote, and thus suggest that previous attempts at their identification should be reappraised.

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

PubMed

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.

Ultrastructural localisation of protein interactions using conditionally stable nanobodies.

PubMed

Ariotti, Nicholas; Rae, James; Giles, Nichole; Martel, Nick; Sierecki, Emma; Gambin, Yann; Hall, Thomas E; Parton, Robert G

2018-04-01

We describe the development and application of a suite of modular tools for high-resolution detection of proteins and intracellular protein complexes by electron microscopy (EM). Conditionally stable GFP- and mCherry-binding nanobodies (termed csGBP and csChBP, respectively) are characterized using a cell-free expression and analysis system and subsequently fused to an ascorbate peroxidase (APEX) enzyme. Expression of these cassettes alongside fluorescently labelled proteins results in recruitment and stabilisation of APEX, whereas unbound APEX nanobodies are efficiently degraded by the proteasome. This greatly simplifies correlative analyses, enables detection of less-abundant proteins, and eliminates the need to balance expression levels between fluorescently labelled and APEX nanobody proteins. Furthermore, we demonstrate the application of this system to bimolecular complementation ('EM split-fluorescent protein'), for localisation of protein-protein interactions at the ultrastructural level.

Ultrastructural localisation of protein interactions using conditionally stable nanobodies

PubMed Central

Ariotti, Nicholas; Rae, James; Giles, Nichole; Martel, Nick; Sierecki, Emma; Gambin, Yann; Parton, Robert G.

2018-01-01

We describe the development and application of a suite of modular tools for high-resolution detection of proteins and intracellular protein complexes by electron microscopy (EM). Conditionally stable GFP- and mCherry-binding nanobodies (termed csGBP and csChBP, respectively) are characterized using a cell-free expression and analysis system and subsequently fused to an ascorbate peroxidase (APEX) enzyme. Expression of these cassettes alongside fluorescently labelled proteins results in recruitment and stabilisation of APEX, whereas unbound APEX nanobodies are efficiently degraded by the proteasome. This greatly simplifies correlative analyses, enables detection of less-abundant proteins, and eliminates the need to balance expression levels between fluorescently labelled and APEX nanobody proteins. Furthermore, we demonstrate the application of this system to bimolecular complementation (‘EM split-fluorescent protein’), for localisation of protein–protein interactions at the ultrastructural level. PMID:29621251

Automated sub-5 nm image registration in integrated correlative fluorescence and electron microscopy using cathodoluminescence pointers

NASA Astrophysics Data System (ADS)

Haring, Martijn T.; Liv, Nalan; Zonnevylle, A. Christiaan; Narvaez, Angela C.; Voortman, Lenard M.; Kruit, Pieter; Hoogenboom, Jacob P.

2017-03-01

In the biological sciences, data from fluorescence and electron microscopy is correlated to allow fluorescence biomolecule identification within the cellular ultrastructure and/or ultrastructural analysis following live-cell imaging. High-accuracy (sub-100 nm) image overlay requires the addition of fiducial markers, which makes overlay accuracy dependent on the number of fiducials present in the region of interest. Here, we report an automated method for light-electron image overlay at high accuracy, i.e. below 5 nm. Our method relies on direct visualization of the electron beam position in the fluorescence detection channel using cathodoluminescence pointers. We show that image overlay using cathodoluminescence pointers corrects for image distortions, is independent of user interpretation, and does not require fiducials, allowing image correlation with molecular precision anywhere on a sample.

Automated sub-5 nm image registration in integrated correlative fluorescence and electron microscopy using cathodoluminescence pointers.

PubMed

Haring, Martijn T; Liv, Nalan; Zonnevylle, A Christiaan; Narvaez, Angela C; Voortman, Lenard M; Kruit, Pieter; Hoogenboom, Jacob P

2017-03-02

In the biological sciences, data from fluorescence and electron microscopy is correlated to allow fluorescence biomolecule identification within the cellular ultrastructure and/or ultrastructural analysis following live-cell imaging. High-accuracy (sub-100 nm) image overlay requires the addition of fiducial markers, which makes overlay accuracy dependent on the number of fiducials present in the region of interest. Here, we report an automated method for light-electron image overlay at high accuracy, i.e. below 5 nm. Our method relies on direct visualization of the electron beam position in the fluorescence detection channel using cathodoluminescence pointers. We show that image overlay using cathodoluminescence pointers corrects for image distortions, is independent of user interpretation, and does not require fiducials, allowing image correlation with molecular precision anywhere on a sample.

Automated sub-5 nm image registration in integrated correlative fluorescence and electron microscopy using cathodoluminescence pointers

PubMed Central

Haring, Martijn T.; Liv, Nalan; Zonnevylle, A. Christiaan; Narvaez, Angela C.; Voortman, Lenard M.; Kruit, Pieter; Hoogenboom, Jacob P.

2017-01-01

In the biological sciences, data from fluorescence and electron microscopy is correlated to allow fluorescence biomolecule identification within the cellular ultrastructure and/or ultrastructural analysis following live-cell imaging. High-accuracy (sub-100 nm) image overlay requires the addition of fiducial markers, which makes overlay accuracy dependent on the number of fiducials present in the region of interest. Here, we report an automated method for light-electron image overlay at high accuracy, i.e. below 5 nm. Our method relies on direct visualization of the electron beam position in the fluorescence detection channel using cathodoluminescence pointers. We show that image overlay using cathodoluminescence pointers corrects for image distortions, is independent of user interpretation, and does not require fiducials, allowing image correlation with molecular precision anywhere on a sample. PMID:28252673

Hypomyelination associated with bovine viral diarrhea virus type 2 infection in a longhorn calf.

PubMed

Porter, B F; Ridpath, J F; Calise, D V; Payne, H R; Janke, J J; Baxter, D G; Edwards, J F

2010-07-01

A newborn Longhorn heifer calf presented with generalized tremors, muscle fasciculations, ataxia, and nystagmus. At necropsy, no gross central nervous system lesions were observed. Histologically, the brain and spinal cord had mild to moderate diffuse microgliosis and astrocytosis, minimal nonsuppurative encephalitis, and decreased myelin staining. Ultrastructural examination revealed thinning and absence of myelin sheaths. Various cell types were immunohistochemically positive for bovine viral diarrhea virus (BVDV). Noncytopathogenic BVDV was isolated from the brain and identified as BVDV type 2 by phylogenetic analysis. BVDV-induced hypomyelination is rare and analogous to lesions in neonates infected with border disease and classical swine fever viruses. This is the first documented case of hypomyelination in a calf specifically attributed to BVDV type 2 and the first description of the ultrastructural appearance of BVDV-induced hypomyelination.

Simultaneous cathodoluminescence and electron microscopy cytometry of cellular vesicles labeled with fluorescent nanodiamonds

NASA Astrophysics Data System (ADS)

Nagarajan, Sounderya; Pioche-Durieu, Catherine; Tizei, Luiz H. G.; Fang, Chia-Yi; Bertrand, Jean-Rémi; Le Cam, Eric; Chang, Huan-Cheng; Treussart, François; Kociak, Mathieu

2016-06-01

Light and Transmission Electron Microscopies (LM and TEM) hold potential in bioimaging owing to the advantages of fast imaging of multiple cells with LM and ultrastructure resolution offered by TEM. Integrated or correlated LM and TEM are the current approaches to combine the advantages of both techniques. Here we propose an alternative in which the electron beam of a scanning TEM (STEM) is used to excite concomitantly the luminescence of nanoparticle labels (a process known as cathodoluminescence, CL), and image the cell ultrastructure. This CL-STEM imaging allows obtaining luminescence spectra and imaging ultrastructure simultaneously. We present a proof of principle experiment, showing the potential of this technique in image cytometry of cell vesicular components. To label the vesicles we used fluorescent diamond nanocrystals (nanodiamonds, NDs) of size ~150 nm coated with different cationic polymers, known to trigger different internalization pathways. Each polymer was associated with a type of ND with a different emission spectrum. With CL-STEM, for each individual vesicle, we were able to measure (i) their size with nanometric resolution, (ii) their content in different ND labels, and realize intracellular component cytometry. In contrast to the recently reported organelle flow cytometry technique that requires cell sonication, CL-STEM-based image cytometry preserves the cell integrity and provides a much higher resolution in size. Although this novel approach is still limited by a low throughput, the automatization of data acquisition and image analysis, combined with improved intracellular targeting, should facilitate applications in cell biology at the subcellular level.Light and Transmission Electron Microscopies (LM and TEM) hold potential in bioimaging owing to the advantages of fast imaging of multiple cells with LM and ultrastructure resolution offered by TEM. Integrated or correlated LM and TEM are the current approaches to combine the advantages of both techniques. Here we propose an alternative in which the electron beam of a scanning TEM (STEM) is used to excite concomitantly the luminescence of nanoparticle labels (a process known as cathodoluminescence, CL), and image the cell ultrastructure. This CL-STEM imaging allows obtaining luminescence spectra and imaging ultrastructure simultaneously. We present a proof of principle experiment, showing the potential of this technique in image cytometry of cell vesicular components. To label the vesicles we used fluorescent diamond nanocrystals (nanodiamonds, NDs) of size ~150 nm coated with different cationic polymers, known to trigger different internalization pathways. Each polymer was associated with a type of ND with a different emission spectrum. With CL-STEM, for each individual vesicle, we were able to measure (i) their size with nanometric resolution, (ii) their content in different ND labels, and realize intracellular component cytometry. In contrast to the recently reported organelle flow cytometry technique that requires cell sonication, CL-STEM-based image cytometry preserves the cell integrity and provides a much higher resolution in size. Although this novel approach is still limited by a low throughput, the automatization of data acquisition and image analysis, combined with improved intracellular targeting, should facilitate applications in cell biology at the subcellular level. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr01908k

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

PubMed

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

It has been shown that mammalian retinal glial (Müller) cells act as living optical fibers that guide the light through the retinal tissue to the photoreceptor cells (Agte et al., 2011; Franze et al., 2007). However, for nonmammalian species it is unclear whether Müller cells also improve the transretinal light transmission. Furthermore, for nonmammalian species there is a lack of ultrastructural data of the retinal cells, which, in general, delivers fundamental information of the retinal function, i.e. the vision of the species. A detailed study of the cellular ultrastructure provides a basic approach of the research. Thus, the aim of the present study was to investigate the retina of the spectacled caimans at electron and light microscopical levels to describe the structural features. For electron microscopy, we used a superfast microwave fixation procedure in order to achieve more precise ultrastructural information than common fixation techniques. As result, our detailed ultrastructural study of all retinal parts shows structural features which strongly indicate that the caiman retina is adapted to dim light and night vision. Various structural characteristics of Müller cells suppose that the Müller cell may increase the light intensity along the path of light through the neuroretina and, thus, increase the sensitivity of the scotopic vision of spectacled caimans. Müller cells traverse the whole thickness of the neuroretina and thus may guide the light from the inner retinal surface to the photoreceptor cell perikarya and the Müller cell microvilli between the photoreceptor segments. Thick Müller cell trunks/processes traverse the layers which contain light-scattering structures, i.e., nerve fibers and synapses. Large Müller cell somata run through the inner nuclear layer and contain flattened, elongated Müller cell nuclei which are arranged along the light path and, thus, may reduce the loss of the light intensity along the retinal light path. The 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.

On the bending properties of porcine mitral, tricuspid, aortic, and pulmonary valve leaflets.

PubMed

Brazile, Bryn; Wang, Bo; Wang, Guangjun; Bertucci, Robbin; Prabhu, Raj; Patnaik, Sourav S; Butler, J Ryan; Claude, Andrew; Brinkman-Ferguson, Erin; Williams, Lakiesha N; Liao, Jun

2015-01-01

The atrioventricular valve leaflets (mitral and tricuspid) are different from the semilunar valve leaflets (aortic and pulmonary) in layered structure, ultrastructural constitution and organization, and leaflet thickness. These differences warrant a comparative look at the bending properties of the four types of leaflets. We found that the moment-curvature relationships in atrioventricular valves were stiffer than in semilunar valves, and the moment-curvature relationships of the left-side valve leaflets were stiffer than their morphological analog of the right side. These trends were supported by the moment-curvature curves and the flexural rigidity analysis (EI value decreased from mitral, tricuspid, aortic, to pulmonary leaflets). However, after taking away the geometric effect (moment of inertia I), the instantaneous effective bending modulus E showed a reversed trend. The overall trend of flexural rigidity (EI: mitral > tricuspid > aortic > pulmonary) might be correlated with the thickness variations among the four types of leaflets (thickness: mitral > tricuspid > aortic > pulmonary). The overall trend of the instantaneous effective bending modulus (E: mitral < tricuspid < aortic < pulmonary) might be correlated to the layered fibrous ultrastructures of the four types of leaflets, of which the fibers in mitral and tricuspid leaflets were less aligned, and the fibers in aortic and pulmonary leaflets were highly aligned. We also found that, for all types of leaflets, moment-curvature relationships are stiffer in against-curvature (AC) bending than in with-curvature bending (WC), which implies that leaflets tend to flex toward their natural curvature and comply with blood flow. Lastly, we observed that the leaflets were stiffer in circumferential bending compared with radial bending, likely reflecting the physiological motion of the leaflets, i.e., more bending moment and movement were experienced in radial direction than circumferential direction.

A combination of stereological methods, biochemistry and electron microscopy for the investigation of drug treatment effects in experimental animals.

PubMed

De Moraes, Alan C N; Andrade, Cherley B V; Salata, Camila; Nascimento, Ana L R; Ramos, Isalira P; Goldenberg, Regina C S; Carvalho, Jorge J; Machado, Ana C S

2016-03-01

Some chemotherapeutic agents used for breast cancer (BC) treatment can induce severe side effects in the ovarian tissue. The combination of cyclophosphamide and docetaxel (TC) is widely used for BC treatment; however, its late effects in the ovary are not completely understood. The main purpose of this study was to evaluate the structural and ultrastructural alterations in the ovarian stroma induced by TC treatment. Wistar rats were divided into two groups: a control group and a TC group. They were euthanized 5 months after the end of treatment, and their plasma and ovaries were collected. Important alterations were noted. The serum estradiol level was significantly reduced in the TC group compared with the control group. Additionally, the number of apoptotic nuclei was higher in the TC group. The role of the inflammatory response in the development of ovarian damage was investigated, and we found an increased number of mast cells and increased expression of TNF-α in the TC group. The involvement of fibrosis was also investigated. The results showed that the TC group had increased expression levels of TGF-β1, collagen type I (col-I) and collagen type III (col-III) compared with the control group. Ultrastructural analysis revealed the presence of collagen fibrils in the treated group and illustrated that the ovarian tissue architecture was more disorganized in this group than in the control group. The results from this study are important in the study of chemotherapy-induced ovarian failure and provide further insight into the mechanisms involved in the development of this disease. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

Effects of chronic malnourishment and aging on the ultrastructure of pyramidal cells of the dorsal hippocampus.

PubMed

Castro-Chavira, Susana Angelica; Aguilar-Vázquez, Azucena Ruth; Martínez-Chávez, Yvonne; Palma, Lourdes; Padilla-Gómez, Euridice; Diaz-Cintra, Sofia

2016-10-01

Malnourishment (M) produces permanent alterations during the development of the CNS and might modify the aging process. In pyramidal neurons (PN) of the hippocampus, which are associated with learning and memory performance, few studies have focused on changes at the subcellular level under chronic malnutrition (ChM) in young (Y, 2 months old) and aged (A, 22 months old) rats. The present work evaluated the extent to which ChM disrupts organelles in PN of the dorsal hippocampus CA1 as compared to controls (C). Ultrastructural analysis was performed at 8000×  and 20 000×  magnification: Nucleus eccentricity and somatic, cytoplasmic, and nuclear areas were measured; and in the PN perikaryon, density indices (number of organelles/cytoplasmic area) of Golgi membrane systems (GMS, normal, and swollen), mitochondria (normal and abnormal), and vacuolated organelles (lysosomes, lipofuscin granules, and multivesicular bodies (MVB)) were determined. The density of abnormal mitochondria, swollen GMS, and MVB increased significantly in the AChM group compared to the other groups. The amount of lipofuscin was significantly greater in the AChM than in the YChM groups - a sign of oxidative stress due to malnutrition and aging; however, in Y animals, ChM showed no effect on organelle density or the cytoplasmic area. An increased density of lysosomes as well as nucleus eccentricity was observed in the AC group, which also showed an increase in the cytoplasmic area. Malnutrition produces subcellular alterations in vulnerable hippocampal pyramidal cells, and these alterations may provide an explanation for the previously reported deficient performance of malnourished animals in a spatial memory task in which aging and malnutrition were shown to impede the maintenance of long-term memory.

Lactobacillus plantarum culture supernatants improve intestinal tissue exposed to deoxynivalenol.

PubMed

Maidana, L G; Gerez, J; Pinho, F; Garcia, S; Bracarense, A P F L

2017-10-02

In the present study, histological, morphometrical and ultrastructural analysis were performed to investigate intestinal mucosa changes in piglets exposed to deoxynivalenol alone or associated with two strains of Lactobacillus plantarum and the respective culture supernatants. Jejunal explants were incubated for 4h in culture medium with a) only culture medium (DMEM, control group), b) deoxynivalenol (DON, 10μM), c) heat-inactivated Lactobacillus plantarum strain1 - LP1 (1.1×10 8 CFU/ml) plus DON, d) heat-inactivated Lactobacillus plantarum strain2-LP2 (2.0×10 9 CFU/ml) plus DON, e) heat-inactivated Lactobacillus plantarum strain1 culture supernatant (CS1) plus DON, and f) heat-inactivated Lactobacillus plantarum strain1 culture supernatant (CS1) plus DON. Explants exposed to DON and DON plus LP1 and LP2 showed a significant increase in histological changes (mainly villi atrophy and apical necrosis) and a significant decrease in villi height when compared to unexposed explants. However, explants treated with CS1+DON and CS2+DON remained similar to the control group both in histological and morphometrical aspects. DON also induced a significant decrease in goblet cell density compared to control whereas CS1+DON treatment induced an increase in the number of goblet cells in comparison to DON explants. In addition, ultrastructural assessment showed control, CS1+DON and CS2+DON explants with well delineated finger shape villi, meanwhile DON-treated, LP1+DON and LP2+DON explants showed a severe villi atrophy with leukocytes exudation on the intestinal surface. Taken together, our results indicate that the culture supernatant treatment reduced the toxic effects induced by DON on intestinal tissue and may contribute as an alternative strategy to reduce mycotoxin toxicity. Copyright © 2017 Elsevier GmbH. All rights reserved.

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

PubMed

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 < .01) with preservation of calcium/phosphorus ratio in that structure (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 < .01). This study shows that T1DM may disturb 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.

Casein phosphopeptide-amorphous calcium phosphate remineralization of primary teeth early enamel lesions.

PubMed

Zhou, Chunhua; Zhang, Dongliang; Bai, Yuxing; Li, Song

2014-01-01

Early childhood caries (ECC) is a serious problem that progresses rapidly and often goes untreated. Current traumatic treatments may be replaced by safe and effective remineralization at very early stages. The aim of this in vitro study was to evaluate the remineralization effects of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste on enamel lesions by assessing ultrastructure, nanomechanical properties, and compound and elemental analysis. Enamel specimens from 6-year-old children were divided into groups: (1) native enamel; (2) water as negative control; (3) 500ppm NaF as positive control; and (4-7) CPP-ACP paste for 4, 8, 12, and 24h, as test groups. Ultrastructure and roughness were observed by atomic force microscopy (AFM); nanohardness and elastic modulus were measured by nanoindentation; compound and crystal size of enamel surface patterns were investigated by X-ray diffractometer (XRD). An electron microprobe (EPMA) was used for element analysis. Data were analyzed using one-way ANOVA. The CPP-ACP paste repaired the microstructure of enamel, including prism and interprism, through significantly increased hydroxyapatite crystal size (12.06±0.21nm) and Ca/P molar ratios (1.637±0.096) as compared with NaF (8.56±0.13nm crystal size and 1.397±0.086 Ca/P, p<0.01). Both CPP-ACP and NaF decrease roughness, and increase the nanohardness and elastic modulus, with no significant differences between the materials. The CPP-ACP paste is more suitable for children than NaF, due to advantages for remineralization. The AFM, nanoindentation, EPMA, and XRD are very helpful methods for further understanding of microscale and nanoscale remineralization mechanisms. Copyright © 2013 Elsevier Ltd. All rights reserved.

Sensitivity of Aspergillus nidulans to the Cellulose Synthase Inhibitor Dichlobenil: Insights from Wall-Related Genes’ Expression and Ultrastructural Hyphal Morphologies

PubMed Central

Obersriebnig, Michael; Salerno, Marco; Pum, Dietmar; Strauss, Joseph

2013-01-01

The fungal cell wall constitutes an important target for the development of antifungal drugs, because of its central role in morphogenesis, development and determination of fungal-specific molecular features. Fungal walls are characterized by a network of interconnected glycoproteins and polysaccharides, namely α-, β-glucans and chitin. Cell walls promptly and dynamically respond to environmental stimuli by a signaling mechanism, which triggers, among other responses, modulations in wall biosynthetic genes’ expression. Despite the absence of cellulose in the wall of the model filamentous fungus Aspergillus nidulans, we found in this study that fungal growth, spore germination and morphology are affected by the addition of the cellulose synthase inhibitor dichlobenil. Expression analysis of selected genes putatively involved in cell wall biosynthesis, carried out at different time points of drug exposure (i.e. 0, 1, 3, 6 and 24 h), revealed increased expression for the putative mixed linkage β-1,3;1,4 glucan synthase celA together with the β-1,3-glucan synthase fksA and the Rho-related GTPase rhoA. We also compared these data with the response to Congo Red, a known plant/fungal drug affecting both chitin and cellulose biosynthesis. The two drugs exerted different effects at the cell wall level, as shown by gene expression analysis and the ultrastructural features observed through atomic force microscopy and scanning electron microscopy. Although the concentration of dichlobenil required to affect growth of A. nidulans is approximately 10-fold higher than that required to inhibit plant cellulose biosynthesis, our work for the first time demonstrates that a cellulose biosynthesis inhibitor affects fungal growth, changes fungal morphology and expression of genes connected to fungal cell wall biosynthesis. PMID:24312197

Ultrastructural identification of peripheral myelin proteins by a pre-embedding immunogold labeling method.

PubMed

Canron, Marie-Hélène; Bouillot, Sandrine; Favereaux, Alexandre; Petry, Klaus G; Vital, Anne

2003-03-01

Ultrastructural immunolabeling of peripheral nervous system components is an important tool to study the relation between structure and function. Owing to the scarcity of certain antigens and the dense structure of the peripheral nerve, a pre-embedding technique is likely appropriate. After several investigations on procedures for pre-embedding immunolabeling, we propose a method that offers a good compromise between detection of antigenic sites and preservation of morphology at the ultrastructural level, and that is easy to use and suitable for investigations on peripheral nerve biopsies from humans. Pre-fixation by immersion in paraformaldehyde/glutaraldehyde is necessary to stabilize the ultrastructure. Then, ultrasmall gold particles with silver enhancement are advised. Antibodies against myelin protein zero and myelin basic protein were chosen for demonstration. The same technique was applied to localize a 35 kDa myelin protein.

Relationship between histopathological changes in post partum renal biopsies and renal function tests of African women with early onset pre-eclampsia.

PubMed

Khedun, S M; Naicker, T; Moodley, J

2000-05-01

To improve the diagnostic accuracy of concurrent renal disease in hypertension of pregnancy, biopsy evaluation is essential. In addition, establishing underlying renal disease is important for prognosis on future pregnancies. We therefore designed a study to determine the diagnostic yield of postpartum renal biopsy and the nature and frequency of complications associated with this procedure. Also, to determine relationships, if any, between renal function tests and ultrastructural and histopathological findings. Fifty renal biopsies were performed in the immediate postpartum period in black African women with early onset pre-eclampsia. Each biopsy specimen was placed in a separate container and coded so that sampling was unknown to the electron microscopist. Each biopsy specimen was divided into three parts, and processed and stained for light, fluorescent and transmission electron microscopy using conventional techniques. Renal tissue biopsies were adequate for diagnostic purposes in all cases. There were no complications in any of the 50 patients studied. Ultrastructural examination confirmed the light microscopy findings. In addition the ultrastructural findings showed intramembranous deposits, foot process fusion and mesangial deposits. In 16 patients with normal renal function tests; the biopsies evaluation from these patients showed ultrastructural changes. In the remaining 34 patients with abnormal renal function tests of varying severity; biopsy evaluation from these patients showed both ultrastructural and histopathological changes. Renal biopsy procedure is safe, and ultrastructural and histological findings obtained from postpartum renal biopsies are more informative than the routine renal function tests.

Spermiogenesis and Taxonomical Values of Sperm Ultrastructures in Male Crassostrea ariakensis (Fujita & Wakiya, 1929) (Pteroirmorphia: Ostreidae) in the Estuary of the Seomjin River, Korea

PubMed Central

Son, Pal Won; Chung, Jae Seung; Kim, Jin Hee; Kim, Sung Han; Chung, Ee-Yung

2014-01-01

Characteristics of the developmental stages of spermatids during spermiogenesis and phylogenetic classicfication of the species using sperm ultrastructures in male Crassostrea ariakensis were investigated by transmission electron microscope observations. The morphology of the spermatozoon of this species has a primitive type and is similar to those of Ostreidae. Ultrastructures of mature sperms are composed of broad, modified cap-shaped acrosomal vesicle and an axial rod in subacrosomal materials on an oval nucleus, four spherical mitochondria in the sperm midpiece, and satellite fibres which appear near the distal centriole. The axoneme of the sperm tail shows a 9+2 structure. Accordingly, the ultrastructural characteristics of mature sperm of C. ariakensis resemble to those of other investigated ostreids in Ostreidae in the subclass Pteriomorphia. In this study, particularly, two transverse bands (stripes) appear at the anterior region of the acrosomal vesicle of this species, unlike two or three transverse bands (stripes) in C. gigas. It is assumed that differences in this acrosomal substructure are associated with the inability of fertilization between the genus Crassostrea and other genus species in Ostreidae. Therefore, we can use sperm ultrastructures and morphologies in the resolution of taxonomic relationships within the Ostreidae in the subclass Pteriomorphia. These spermatozoa, which contain several ultrastructures such as acrosomal vesicle, an axial rod in the sperm head part and four mitochondria and satellite fibres in the sperm midpiece, belong to the family Ostreidae in the subclass Pteriomorphia. PMID:25949188

The effect of starvation and re-feeding on mitochondrial potential in the midgut of Neocaridina davidi (Crustacea, Malacostraca)

PubMed Central

Włodarczyk, Agnieszka; Sonakowska, Lidia; Kamińska, Karolina; Marchewka, Angelika; Wilczek, Grażyna; Wilczek, Piotr; Student, Sebastian; Rost-Roszkowska, Magdalena

2017-01-01

The midgut in the freshwater shrimp Neocaridina davidi (previously named N. heteropoda) (Crustacea, Malacostraca) is composed of a tube-shaped intestine and a large hepatopancreas that is formed by numerous blind-ended tubules. The precise structure and ultrastructure of these regions were presented in our previous papers, while here we focused on the ultrastructural changes that occurred in the midgut epithelial cells (D-cells in the intestine, B- and F- cells in the hepatopancreas) after long-term starvation and re-feeding. We used transmission electron microscopy, light and confocal microscopes and flow cytometry to describe all of the changes that occurred due to the stressor with special emphasis on mitochondrial alterations. A quantitative assessment of cells with depolarized mitochondria helped us to establish whether there is a relationship between starvation, re-feeding and the inactivation/activation of mitochondria. The results of our studies showed that in the freshwater shrimp N. davidi that were analyzed, long-term starvation activates the degeneration of epithelial cells at the ultrastructural level and causes an increase of cells with depolarized (non-active) mitochondria. The process of re-feeding leads to the gradual regeneration of the cytoplasm of the midgut epithelial cells; however, these changes were observed at the ultrastructural level. Additionally, re-feeding causes the regeneration of mitochondrial ultrastructure. Therefore, we can state that the increase in the number of cells with polarized mitochondria occurs slowly and does not depend on ultrastructural alterations. PMID:28282457

The effect of starvation and re-feeding on mitochondrial potential in the midgut of Neocaridina davidi (Crustacea, Malacostraca).

PubMed

Włodarczyk, Agnieszka; Sonakowska, Lidia; Kamińska, Karolina; Marchewka, Angelika; Wilczek, Grażyna; Wilczek, Piotr; Student, Sebastian; Rost-Roszkowska, Magdalena

2017-01-01

The midgut in the freshwater shrimp Neocaridina davidi (previously named N. heteropoda) (Crustacea, Malacostraca) is composed of a tube-shaped intestine and a large hepatopancreas that is formed by numerous blind-ended tubules. The precise structure and ultrastructure of these regions were presented in our previous papers, while here we focused on the ultrastructural changes that occurred in the midgut epithelial cells (D-cells in the intestine, B- and F- cells in the hepatopancreas) after long-term starvation and re-feeding. We used transmission electron microscopy, light and confocal microscopes and flow cytometry to describe all of the changes that occurred due to the stressor with special emphasis on mitochondrial alterations. A quantitative assessment of cells with depolarized mitochondria helped us to establish whether there is a relationship between starvation, re-feeding and the inactivation/activation of mitochondria. The results of our studies showed that in the freshwater shrimp N. davidi that were analyzed, long-term starvation activates the degeneration of epithelial cells at the ultrastructural level and causes an increase of cells with depolarized (non-active) mitochondria. The process of re-feeding leads to the gradual regeneration of the cytoplasm of the midgut epithelial cells; however, these changes were observed at the ultrastructural level. Additionally, re-feeding causes the regeneration of mitochondrial ultrastructure. Therefore, we can state that the increase in the number of cells with polarized mitochondria occurs slowly and does not depend on ultrastructural alterations.

Aging-related anatomical and biochemical changes in lymphatic collectors impair lymph transport, fluid homeostasis, and pathogen clearance

PubMed Central

Zolla, Valerio; Nizamutdinova, Irina Tsoy; Scharf, Brian; Clement, Cristina C; Maejima, Daisuke; Akl, Tony; Nagai, Takashi; Luciani, Paola; Leroux, Jean-Christophe; Halin, Cornelia; Stukes, Sabriya; Tiwari, Sangeeta; Casadevall, Arturo; Jacobs, William R; Entenberg, David; Zawieja, David C; Condeelis, John; Fooksman, David R; Gashev, Anatoliy A; Santambrogio, Laura

2015-01-01

The role of lymphatic vessels is to transport fluid, soluble molecules, and immune cells to the draining lymph nodes. Here, we analyze how the aging process affects the functionality of the lymphatic collectors and the dynamics of lymph flow. Ultrastructural, biochemical, and proteomic analysis indicates a loss of matrix proteins, and smooth muscle cells in aged collectors resulting in a decrease in contraction frequency, systolic lymph flow velocity, and pumping activity, as measured in vivo in lymphatic collectors. Functionally, this impairment also translated into a reduced ability for in vivo bacterial transport as determined by time-lapse microscopy. Ultrastructural and proteomic analysis also indicates a decrease in the thickness of the endothelial cell glycocalyx and loss of gap junction proteins in aged lymph collectors. Redox proteomic analysis mapped an aging-related increase in the glycation and carboxylation of lymphatic’s endothelial cell and matrix proteins. Functionally, these modifications translate into apparent hyperpermeability of the lymphatics with pathogen escaping from the collectors into the surrounding tissue and a decreased ability to control tissue fluid homeostasis. Altogether, our data provide a mechanistic analysis of how the anatomical and biochemical changes, occurring in aged lymphatic vessels, compromise lymph flow, tissue fluid homeostasis, and pathogen transport. PMID:25982749

Glomerular anionic site distribution in nonproteinuric rats. A computer-assisted morphometric analysis.

PubMed

Pilia, P A; Swain, R P; Williams, A V; Loadholt, C B; Ainsworth, S K

1985-12-01

The cationic ultrastructural tracer polyethyleneimine (PEI: pI approximately equal to 11.0), binds electrophysically to uniformly spaced discrete electron-dense anionic sites present in the laminae rarae of the rat glomerular basement membrane (GBM), mesangial reflections of the GBM, Bowman's capsule, and tubular basement membranes when administered intravenously. Computer-assisted morphometric analysis of glomerular anionic sites reveals that the maximum concentration of stainable lamina rara externa (lre) sites (21/10,000 A GBM) occurs 60 minutes after PEI injection with a site-site interspacing of 460 A. Lamina rara interna (lri) sites similarly demonstrate a maximum concentration (20/10,000 A GBM) at 60 minutes with a periodicity of 497 A. The concentration and distribution of anionic sites within the lri was irregular in pattern and markedly decreased in number, while the lre possesses an electrical field that is highly regular at all time intervals analyzed (15, 30, 60, 120, 180, 240, and 300 minutes). Immersion and perfusion of renal tissue with PEI reveals additional heavy staining of the epithelial and endothelial cell sialoprotein coatings. PEI appears to bind to glomerular anionic sites reversibly: ie, between 60 and 180 minutes the concentration of stained sites decreases. At 300 minutes, the interspacing once again approaches the 60-minute concentration. This suggests a dynamic turnover or dissociation followed by a reassociation of glomerular negatively charged PEI binding sites. In contrast, morphometric analysis of anionic sites stained with lysozyme and protamine sulfate reveals interspacings of 642 A and 585 A, respectively; in addition, these tracers produce major glomerular ultrastructural alterations and induce transient proteinuria. PEI does not induce proteinuria in rats, nor does it produce glomerular morphologic alterations when ten times the tracer dosage is administered intravenously. These findings indicate that the choice of ultrastructural charge tracer, the method of administering the tracer, and the time selected for analysis of tissue after administration of tracer significantly influences results. Morphometric analysis of the distribution of glomerular anionic sites in nonproteinuric rats provides a method of evaluating quantitative alterations of the glomerular charge barrier in renal disease models.

Marine bivalve shell geochemistry and ultrastructure from modern low pH environments: environmental effect versus experimental bias

NASA Astrophysics Data System (ADS)

Hahn, S.; Rodolfo-Metalpa, R.; Griesshaber, E.; Schmahl, W. W.; Buhl, D.; Hall-Spencer, J. M.; Baggini, C.; Fehr, K. T.; Immenhauser, A.

2012-05-01

Bivalve shells can provide excellent archives of past environmental change but have not been used to interpret ocean acidification events. We investigated carbon, oxygen and trace element records from different shell layers in the mussels Mytilus galloprovincialis combined with detailed investigations of the shell ultrastructure. Mussels from the harbour of Ischia (Mediterranean, Italy) were transplanted and grown in water with mean pHT 7.3 and mean pHT 8.1 near CO2 vents on the east coast of the island. Most prominently, the shells recorded the shock of transplantation, both in their shell ultrastructure, textural and geochemical record. Shell calcite, precipitated subsequently under acidified seawater responded to the pH gradient by an in part disturbed ultrastructure. Geochemical data from all test sites show a strong metabolic effect that exceeds the influence of the low-pH environment. These field experiments showed that care is needed when interpreting potential ocean acidification signals because various parameters affect shell chemistry and ultrastructure. Besides metabolic processes, seawater pH, factors such as salinity, water temperature, food availability and population density all affect the biogenic carbonate shell archive.

Ultrastructural and cytochemical evidence for single impulse initiation zones in vestibular macular nerve fibers of rat

NASA Technical Reports Server (NTRS)

Ross, Muriel D.; Chee, Oliver; Black, Samuel; Cutler, Lynn

1991-01-01

Cupric ion-ferricyanide labeling methods and related ferrocyanide-stained tissues were used to locate the characterize, at the ultrastructural level, presumptive impulse initiation zones in the three types of vestibular macular nerve fibers. Large-diameter, M-type vestibular nerve fibers terminate in a calyx at the heminode, and labeling is coextensive with the base of the calyx. Intermediate, M/U-type nerve fibers have short, unmyelinated preterminal segments that sometimes bifurcate intamacularly, and small-diameter, U-type nerve fibers have long, unmyelinated preterminal axons and up to three branches. Preterminals of these nerve fibers display ultrastructural heterogeneity that is correlated with labeling patterns for sodium channels and/or associated polyanionic sites. They have a nodelike ultrastructure and label heavily from near the heminode to the base of the macula. Their intramacular branches, less organized ultrastructurally, label only slightly. Results indicate that vestibular nerve fibers have one impulse initiation zone, located near the heminode, that varies in length according to nerve fiber type. Structural heterogeneity may favor impulse conduction in the central direction, and length of the impulse initiation zone could influence nerve discharge patterns.

Techniques to assess bone ultrastructure organization: orientation and arrangement of mineralized collagen fibrils

PubMed Central

Georgiadis, Marios; Müller, Ralph; Schneider, Philipp

2016-01-01

Bone's remarkable mechanical properties are a result of its hierarchical structure. The mineralized collagen fibrils, made up of collagen fibrils and crystal platelets, are bone's building blocks at an ultrastructural level. The organization of bone's ultrastructure with respect to the orientation and arrangement of mineralized collagen fibrils has been the matter of numerous studies based on a variety of imaging techniques in the past decades. These techniques either exploit physical principles, such as polarization, diffraction or scattering to examine bone ultrastructure orientation and arrangement, or directly image the fibrils at the sub-micrometre scale. They make use of diverse probes such as visible light, X-rays and electrons at different scales, from centimetres down to nanometres. They allow imaging of bone sections or surfaces in two dimensions or investigating bone tissue truly in three dimensions, in vivo or ex vivo, and sometimes in combination with in situ mechanical experiments. The purpose of this review is to summarize and discuss this broad range of imaging techniques and the different modalities of their use, in order to discuss their advantages and limitations for the assessment of bone ultrastructure organization with respect to the orientation and arrangement of mineralized collagen fibrils. PMID:27335222

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

PubMed

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.

CNGA3 Deficiency Affects Cone Synaptic Terminal Structure and Function and Leads to Secondary Rod Dysfunction and Degeneration

PubMed Central

Xu, Jianhua; Morris, Lynsie M.; Michalakis, Stylianos; Biel, Martin; Fliesler, Steven J.; Sherry, David M.

2012-01-01

Purpose. To investigate rod function and survival after cone dysfunction and degeneration in a mouse model of cone cyclic nucleotide-gated (CNG) channel deficiency. Methods. Rod function and survival in mice with cone CNG channel subunit CNGA3 deficiency (CNGA3−/− mice) were evaluated by electroretinographic (ERG), morphometric, and Western blot analyses. The arrangement, integrity, and ultrastructure of photoreceptor terminals were investigated by immunohistochemistry and electron microscopy. Results. The authors found loss of cone function and cone death accompanied by impairment of rods and rod-driven signaling in CNGA3−/− mice. Scotopic ERG b-wave amplitudes were reduced by 15% at 1 month, 30% at 6 months, and 40% at 9 months and older, while scotopic a-wave amplitudes were decreased by 20% at 9 months, compared with ERGs of age-matched wild-type mice. Outer nuclear layer thickness in CNGA3−/− retina was reduced by 15% at 12 months compared with age-matched wild-type controls. This was accompanied by a 30%–40% reduction in expression of rod-specific proteins, including rhodopsin, rod transducin α-subunit, and glutamic acid-rich protein (GARP). Cone terminals in the CNGA3−/− retina showed a progressive loss of neurochemical and ultrastructural integrity. Abnormalities were observed as early as 1 month. Disorganized rod terminal ultrastructure was noted by 12 months. Conclusions. These findings demonstrate secondary rod impairment and degeneration after cone degeneration in mice with cone CNG channel deficiency. Loss of cone phototransduction accompanies the compromised integrity of cone terminals. With time, rod synaptic structure, function, and viability also become compromised. PMID:22247469

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

PubMed Central

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 hematological resources in wildlife animals and provides a guideline for identification of blood cells in the fishing cat. PMID:17519570

[An electron microscopic analysis of the stimulating and toxic effects of mumie-containing preparations].

PubMed

Rudnev, M I; Maliuk, V I; Stechenko, L A; Maliuk, V I; Fisun, O I; Kuftyreva, T P; Andreenko, T V

1993-01-01

Ultrastructural changes of myocardium cells, neurons of sensorimotor cerebral cortex, endothelium of blood microvessels were registered by transmissive electron microscopy in mice receiving rock balm preparations per os. Both stimulating and toxic effects were observed dependently on used concentrations. This necessitates dosage to be strictly observed.

The ultrastructure of rat palatal mucosa maintained in organ culture.

PubMed Central

Hill, M W

1978-01-01

Palatal mucosa from neonatal rats was examined by electron microscopy after maintenance in a chemically defined medium in organ culture for periods up to 24 days. Throughout the culture period there was little overall change in the explants. Apart from limited disturbances of the basal lamina complex early in the culture period, and the presence of occasional degenerating keratinocytes after 18 days in vitro, the epithelium displayed an ultrastructure comparable with that at the time of explantation. The connective tissue showed greater changes, but despite considerable cell death a viable cell population apparently capable of both phagocytosis and synthesis of extracellular material was maintained. It is concluded that this organ culture system is a valid model for experimental investigations into the behaviour of oral mucosa. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 PMID:744746

Mortality, size of the gonads, and ultrastructure of primordial germ cell in chick embryos treated with gamma-irradiation or injected with donor cells.

PubMed

Maeda, T; Clark, M E; Etches, R J

1998-06-01

The effects of injection and/or gamma-irradiation prior to injection on mortality, size of the gonads, and ultrastructure of primordial germ cell (PGC) were examined after 5 d of incubation. The mortality of embryos injected with donor cells was significantly higher than that of control and irradiated embryos. All irradiated embryos were alive, although their development was delayed compared to those not exposed to irradiation. The size of the gonads of embryos injected with donor cells were similar to those of control embryos, however, the size of the gonads in irradiated embryos was significantly smaller than those of control embryos. The number of PGC in the gonads was significantly decreased by irradiation. There was no notable effect of irradiation or injection on the nuclei and cytoplasmic organelles in PGC.

Ultrastructural observations reveal the presence of channels between cork cells.

PubMed

Teixeira, Rita Teresa; Pereira, Helena

2009-12-01

The ultrastructure of phellem cells of Quercus suber L. (cork oak) and Calotropis procera (Ait) R. Br. were analyzed using electron transmission microscopy to determine the presence or absence of plasmodesmata (PD). Different types of Q. suber cork samples were studied: one year shoots; virgin cork (first periderm), reproduction cork (traumatic periderm), and wet cork. The channel structures of PD were found in all the samples crossing adjacent cell walls through the suberin layer of the secondary wall. Calotropis phellem also showed PD crossing the cell walls of adjacent cells but in fewer numbers compared to Q. suber. In one year stems of cork oak, it was possible to follow the physiologically active PD with ribosomic accumulation next to the aperture of the channel seen in the phellogen cells to the completely obstructed channels in the dead cells that characterize the phellem tissue.

Helium Ion Microscopy (HIM) for the imaging of biological samples at sub-nanometer resolution

NASA Astrophysics Data System (ADS)

Joens, Matthew S.; Huynh, Chuong; Kasuboski, James M.; Ferranti, David; Sigal, Yury J.; Zeitvogel, Fabian; Obst, Martin; Burkhardt, Claus J.; Curran, Kevin P.; Chalasani, Sreekanth H.; Stern, Lewis A.; Goetze, Bernhard; Fitzpatrick, James A. J.

2013-12-01

Scanning Electron Microscopy (SEM) has long been the standard in imaging the sub-micrometer surface ultrastructure of both hard and soft materials. In the case of biological samples, it has provided great insights into their physical architecture. However, three of the fundamental challenges in the SEM imaging of soft materials are that of limited imaging resolution at high magnification, charging caused by the insulating properties of most biological samples and the loss of subtle surface features by heavy metal coating. These challenges have recently been overcome with the development of the Helium Ion Microscope (HIM), which boasts advances in charge reduction, minimized sample damage, high surface contrast without the need for metal coating, increased depth of field, and 5 angstrom imaging resolution. We demonstrate the advantages of HIM for imaging biological surfaces as well as compare and contrast the effects of sample preparation techniques and their consequences on sub-nanometer ultrastructure.

Helium Ion Microscopy (HIM) for the imaging of biological samples at sub-nanometer resolution.

PubMed

Joens, Matthew S; Huynh, Chuong; Kasuboski, James M; Ferranti, David; Sigal, Yury J; Zeitvogel, Fabian; Obst, Martin; Burkhardt, Claus J; Curran, Kevin P; Chalasani, Sreekanth H; Stern, Lewis A; Goetze, Bernhard; Fitzpatrick, James A J

2013-12-17

Scanning Electron Microscopy (SEM) has long been the standard in imaging the sub-micrometer surface ultrastructure of both hard and soft materials. In the case of biological samples, it has provided great insights into their physical architecture. However, three of the fundamental challenges in the SEM imaging of soft materials are that of limited imaging resolution at high magnification, charging caused by the insulating properties of most biological samples and the loss of subtle surface features by heavy metal coating. These challenges have recently been overcome with the development of the Helium Ion Microscope (HIM), which boasts advances in charge reduction, minimized sample damage, high surface contrast without the need for metal coating, increased depth of field, and 5 angstrom imaging resolution. We demonstrate the advantages of HIM for imaging biological surfaces as well as compare and contrast the effects of sample preparation techniques and their consequences on sub-nanometer ultrastructure.

Results of an ultrastructural study comparing stria vascularis with organ of Corti in guinea pigs treated with kanamycin.

PubMed

Gratacap, B; Charachon, R; Stoebner, P

1985-01-01

Ultrastructural study of ototoxicity is well documented with two points of interest: organ of Corti for aminoglycosides and stria vascularis for loop diuretics. As a previous study suggested initial lesions of stria vascularis, an attempt of comparison and of chronological study was made between the organ of Corti and stria vascularis lesions by kanamycin intoxication. The method was devised by J. M. ARAN, with electrophysiological control. We failed to find in the stria vascularis a radial or longitudinal pattern of lesions. We could not discern a chronological injury between the organ of Corti and stria vascularis because both were damaged even in the less deafened animals. Nevertheless, two facts were clarified: hair cell lesions are lysosomial as for the kidney lesions, while stria vascularis lesions are mitochondrial, melanine granulations play a part in drug metabolism (increased number, secretory aspect) and deserve further study.

Ultrastructure of the membrana limitans interna after dye-assisted membrane peeling.

PubMed

Brockmann, Tobias; Steger, Claudia; Westermann, Martin; Nietzsche, Sandor; Koenigsdoerffer, Ekkehart; Strobel, Juergen; Dawczynski, Jens

2011-01-01

The purpose of this study was to investigate the ultrastructure of the membrana limitans interna (internal limiting membrane, ILM) and to evaluate alterations to the retinal cell layers after membrane peeling with vital dyes. Twenty-five patients (25 eyes) who underwent macular hole surgery were included, whereby 12 indocyanine green (ICG)- and 13 brilliant blue G (BBG)-stained ILM were analyzed using light, transmission electron and scanning electron microscopy. Retinal cell fragments on the ILM were identified in both groups using immunohistochemistry. Comparing ICG- and BBG-stained membranes, larger cellular fragments were observed at a higher frequency in the BBG group. Thereby, the findings indicate that ICG permits an enhanced separation of the ILM from the underlying retina with less mechanical destruction. A possible explanation might be seen in the known photosensitivity of ICG, which induces a stiffening and shrinkage of the ILM but also generates retinal toxic metabolites. Copyright © 2011 S. Karger AG, Basel.

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

PubMed

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 2.45 microm +/- 0.74, N=6; and their mean wide is 0.773 microm +/- 0.241, N=11. The evidence on the specific ultrastructural characteristics of the rotifer B. bidentatus is notorious, even more in the male and in the cyst cell. Regarding the ultrastructure of the spermatozoa and the rods, compared to other species they only differ in size, despite their structural resemblance. Our study of the ultraestructure of this species adds useful information that along with molecular data will help clarify the taxonomy of brachionid rotifers.

The chorion ultrastructure of ova of Lophius spp.

PubMed

Colmenero, A I; Tuset, V M; Fortuño, J-M; Sánchez, P

2015-06-01

The chorion surface ultrastructure of unfertilized eggs of black anglerfish Lophius budegassa and white anglerfish Lophius piscatorius was examined by scanning electron microscopy. Species-specific differences were observed. © 2015 The Fisheries Society of the British Isles.

Effects of Electroacupuncture on Interstitial Cells of Cajal (ICC) Ultrastructure and Connexin 43 Protein Expression in the Gastrointestinal Tract of Functional Dyspepsia (FD) Rats

PubMed Central

Zhang, Guoshan; Xie, Shen; Hu, Wei; Liu, Yuer; Liu, Mailan; Liu, Mi; Chang, Xiaorong

2016-01-01

Background Gastrointestinal motility disorder is the main clinical manifestation in functional dyspepsia (FD) patients. Electroacupuncture is effective in improving gastrointestinal motility disorder in FD; however, the underlying mechanism remains unclear. It has been demonstrated that interstitial cells of Cajal (ICC) are pacemaker cells in the gastrointestinal tract, and the pacemaker potential is transmitted to nearby cells through gap junctions between ICC or ICC and the smooth muscle. Therefore, this study aimed to assess the effects of electroacupuncture on ICC ultrastructure and expression of the gap junction protein connexin 43 (Cx43) in FD rats. Material/Methods The animals were randomized into 3 groups: control, model, and electroacupuncture. Electroacupuncture was applied at Zusanli (ST36) in the electroacupuncture group daily for 10 days, while no electroacupuncture was applied to model group animals. Results Ultrastructure of ICC recovered normally in gastric antrum and small intestine specimens was improved, with Cx43 expression levels in these tissues significantly increased in the electroacupuncture group compared with the model group. Conclusions These findings indicated that electroacupuncture is effective in alleviating ICC damage and reduces Cx43 levels in FD rats, and suggest that ICC and Cx43 are involved in electroacupuncture treatment in rats with FD to improve gastrointestinal motility disorders. PMID:27297942

[Ultrastructural pathology of oligodendrocytes in the white matter in continuous paranoid schizophrenia: a role for microglia].

PubMed

Uranova, N A; Vikhreva, O V; Rakhmanova, V I; Orlovskaya, D D

Previously the authors have reported the ultrastructural pathology and deficit of oligodendrocytes in gray and white matter of the prefrontal cortex in schizophrenia. The aim of the study was to determine of the effects of microglia on the ultrastructure of oligodendrocytes in the white matter underlying the prefrontal cortex in continuous schizophrenia. Postmortem morphometric electron microscopic study of oligodendrocytes in close apposition to microglia was performed in white matter underlying the prefrontal cortex (BA10). Eleven cases of chronic continuous schizophrenia and 11 normal controls were studied. Areas of oligodendrocytes, of their nuclei and cytoplasm, volume density (Vv) and the number of mitochondria, vacuoles of endoplasmic reticulum and lipofuscin granules were estimated. Group comparison was performed using ANCOVA. The schizophrenia group differed from the control group by paucity of ribosomes in the cytoplasm of oligodendrocytes, a significant decrease in Vv and the number of mitochondria and increase in the number of lipofuscin granules. Significant correlations between the parameters of lipofuscin granules, mitochondria and vacuoles were found only in the schizophrenia group. The number of lipofuscin granules were correlated positively with the illness duration. Dystrophic alterations of oligodendrocytes attached to microglial cells were found in the white matter of the prefrontal cortex in chronic paranoid schizophrenia as compared to controls. The data obtained suggest that microglia might contribute to abnormalities of energy, lipid and protein metabolism of oligodendrocytes in schizophrenia.

Applications of emerging transmission electron microscopy technology in PCD research and diagnosis.

PubMed

Shoemark, Amelia

2017-01-01

Primary Ciliary Dyskinesia (PCD) is a heterogeneous genetic condition characterized by dysfunction of motile cilia. Patients suffer from chronic infection and inflammation of the upper and lower respiratory tract. Diagnosis of PCD is confirmed by identification of a hallmark defect of ciliary ultrastructure or by identification of biallelic pathogenic mutations in a known PCD gene. Since the first description of PCD in 1976, assessment of ciliary ultrastructure by transmission electron microscopy (TEM) has been central to diagnosis and research. Electron tomography is a technique whereby a series of transmission electron micrographs are collected at different angles and reconstructed into a single 3D model of a specimen. Electron tomography provides improved spatial information and resolution compared to a single micrograph. Research by electron tomography has revealed new insight into ciliary ultrastructure and consequently ciliary function at a molecular and cellular level. Gene discovery studies in PCD have utilized electron tomography to define the structural consequences of variants in cilia genes. Modern transmission electron microscopes capable of electron tomography are increasingly being installed in clinical laboratories. This presents the possibility for the use of tomography technique in a diagnostic setting. This review describes the electron tomography technique, the contribution tomography has made to the understanding of basic cilia structure and function and finally the potential of the technique for use in PCD diagnosis.

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

PubMed

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 < 0.001), the appearance of micropores and triglyceride leakage and release in the conditioned medium (P < 0.05 at 15 min), or adipose tissue interstitium, without appreciable changes in microvascular, stromal, and epidermal components and in the number of apoptotic adipocytes. Clinically, the 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.

Granulocytes of reptilian sauropsids contain beta-defensin-like peptides: a comparative ultrastructural survey.

PubMed

Alibardi, Lorenzo

2013-08-01

The ability of lizards to withstand infections after wounding or amputation of the tail or limbs has suggested the presence of antimicrobial peptides in their tissues. Previous studies on the lizard Anolis carolinensis have identified several beta-defensin-like peptides that may potentially be involved in protection from infections. The present ultrastructural immunocytochemical study has analyzed tissues in different reptilian species in order to localize the cellular source of one of the more expressed beta-defensins previously sequenced in lizard indicated as AcBD15. Beta-defensin-like immunoreactivity is present in some of the larger, nonspecific granules of granulocytes in two lizard species, a snake, the tuatara, and a turtle. The ultrastructural study indicates that only heterophilic and basophilic granulocytes contain this defensin while other cell types from the epidermis, mesenchyme, and dermis, muscles, nerves, cartilage or bone are immunonegative. The study further indicates that not all granules in reptilian granulocytes contain the beta-defensin peptide, suggesting the presence of granules with different content as previously indicated for mammalian neutrophilic leucocytes. No immunolabeling was instead observed in granulocytes of the alligator and chick using this antibody. The present immunocytochemical observations suggest a broad cross-reactivity and conservation of beta-defensin-like sequence or steric motif across lepidosaurians and likely in turtles while archosaurian granulocytes may contain different beta-defensin-like or other peptides. Copyright © 2013 Wiley Periodicals, Inc.

Chronic Hyperglycemia Modulates Rat Osteoporotic Cortical Bone Microarchitecture into Less Fragile Structures

PubMed Central

de Mello-Sampayo, Cristina; Agripino, Alaíde Alves; Stilwell, Duarte; Vidal, Bruno; Fernando, Ana Luisa; Silva-Lima, Beatriz; Vaz, Maria Fátima; Canhão, Helena

2017-01-01

There is controversy concerning the diabetes impact on bone quality, notorious in type 2 diabetic postmenopausal women. One pointed cause might be uncontrolled glycemia. In this study, the effect of chronic hyperglycemia in bone turnover, morphology, and biomechanics was evaluated in female Wistar rats in the presence/absence of estrogens (ovariectomy). Animals (n = 28) were divided into sham, ovariectomized (OVX), hyperglycemic (streptozotocin 40 mg/kg, single-dose i.p.-STZ), and hyperglycemic-ovariectomized (STZ + OVX) animals. Blood biomarkers were estimated 60 days postovariectomy. Body weight, vertebral microarchitecture (L4-histomorphometry), femur biomechanical properties (bending tests), tibia ultrastructure (scanning electron microscopy), and femur and urinary calcium (atomic absorption) were also evaluated. The increased PINP/CTX ratio of hyperglycemic animals and the similar ratio between STZ + OVX and healthy animals contrasting with the lower ratio of OVX (in line with its histomorphometric data) suggest a tendency for improved bone formation in hyperglycemic-ovariectomized animals. The increased tibia medullar canal, which contrasts with the unaffected cortical thickness of both hyperglycemic groups while that of OVX decreased, was associated to the increased stiffness and strength of STZ + OVX bones compared to those of OVX, in line with the observed ultrastructure. Concluding, chronic hyperglycemia in ovariectomized female rats causes bone morphological changes that translate positively in the ultrastructure and mechanical properties of cortical bones. PMID:29081798

Primary adenocarcinomas of the human urinary bladder: histochemical, immunological and ultrastructural studies.

PubMed

Alroy, J; Roganovic, D; Banner, B F; Jacobs, J B; Merk, F B; Ucci, A A; Kwan, P W; Coon, J S; Miller, A W

1981-01-01

Neoplastic and non-neoplastic tissue specimens from ten patients with primary adenocarcinoma of the urinary bladder were examined. Most of these tumors were associated with either foci of transitional cell carcinoma and/or with glandular metaplasia of the bladder epithelium. The mucin produced by the neoplastic cells was PAS, alcian blue, mucicarmine, PB/KOH/PAS, and RPB/KOH/PAS-positive. ABH isoantigens of these tumors were not always deleted. Ultrastructurally, the neoplastic cells resembled goblet cells. Their plasma membrane had numerous microvilli with prominent glycocalyx. Proliferation and attenuation of tight junctions were noted. The gap junctions were few and small. Two types of desmosomes were found. The ultrastructural features of the neoplastic cells were attributed in part to the malignant transformation and in part to the direction of their differentiation. We have not observed any distinctive morphologic, histochemical, immunologic or ultrastructural features that might be diagnostic for these adenocarcinomas.

Alterations of leaf cell ultrastructures and AFLP DNA profiles in Earth-grown tomato plants propagated from long-term six years Mir-flown seeds

NASA Astrophysics Data System (ADS)

Liu, Min; Xue, Huai; Pan, Yi; Zhang, Chunhua; Lu, Jinying

Leaf cell ultrastructures and DNA variations in the firstand the second-generation of Earthgrown tomato (Lycopersicon esculentun Mill) plants that had been endured a long-term six years spaceflight in the Mir were compared to their ground-based control plants, under observations with a Transmission Electron Microscope and the Amplification Fragment Length Polymorphism (AFLP) analysis. For alterations in the morphological ultrastructures, one plant among the 11 first-generation plants generated from 30 Mir-flown seeds had a three-layered palisade cell structure, while other 10 first-generation plants and all ground-based controls had one-layered palisade cell structure in leaves. Starch grains were larger and in clusters, numbers of starch grains increased in the chloroplasts in the Mir-flown plants. Leaf cells became contracted and deformed, and cell shape patterns were different in the Mir-flown plants. For the leaf genomic DNA alterations, 34 DNA bands were polymorphic with a 1.32% polymorphism among 2582 DNA bands in the first-generation Mir-flown plants. Band types in the spaceflight treated plants were also different from those in the ground-based control. Of 11 survived first-generation plants, 7 spaceflight treated plants (Plant Nos. 1-6 and No. 9) had a same 7 polymorphic bands and a same 0.27%DNA mutation. The DNA mutation rate was greatest in Plants No.10 and No.7 (0.90% and 0.94%), less in Plant No.11 (0.31%) and least in Plant No.8 (0.20%). For the 38 send-generation plants propagated from the No. 5 Mir-flown seed, 6 DNA bands were polymorphic with a 0.23% polymorphism among 2564 amplified DNA bands. Among those 38 second-generation plants amplified by primer pair (E4: ACC, M8: CTT), one DNA band disappeared in 29 second-generation plants and in the original Mir-flown No. 5 plant, compared to the ground-base controls. Among the 38 second-generation plants generated from the Mir-flown No. 5 seed, the DNA band types of 29 second-generation plants were different from that of the ground-base controls and had a same 6 polymorphic bands and a same 0.23% DNA mutation. For the 49 second-generation plants derived from the Mir-flown No. 6 seed, 7 DNA bands were polymorphic with 0.27% polymorphism among 2564 amplified DNA bands. With only one exception among those 49 second-generation plants amplified by primer pair (E3: ACA, M3: CAG), one DNA band disappeared in 48 second-generation plants and in the original Mir-flown No. 6 plant, compared to the ground-based controls. Among the 49 second-generation plants generated from the Mir-flown No. 6 seed, the DNA band types of 48 second-generation plants were different from that of the ground-base controls and had a same 7 polymorphic bands and a same 0.27% DNA mutation. Our results indicated that leaf cell ultrastructures had been altered and heredity variations had been induced by seeds being exposed to a long-term outer-space environment. Further research is needed to elucidate the dynamics and mechanisms resulting in such variations. Plant biology studies in the space environment may open potential approaches to induce mutations and to screen new plant varieties by ground-based selections among spaceflight treated seeds or seedlings.

Ultrastructural and geochemical characterization of Archean-Paleoproterozoic graphite particles: implications for recognizing traces of life in highly metamorphosed rocks.

PubMed

Schiffbauer, James D; Yin, Leiming; Bodnar, Robert J; Kaufman, Alan J; Meng, Fanwei; Hu, Jie; Shen, Bing; Yuan, Xunlai; Bao, Huiming; Xiao, Shuhai

2007-08-01

Abundant graphite particles occur in amphibolite-grade quartzite of the Archean-Paleoproterozoic Wutai Metamorphic Complex in the Wutaishan area of North China. Petrographic thin section observations suggest that the graphite particles occur within and between quartzite clasts and are heterogeneous in origin. Using HF maceration techniques, the Wutai graphite particles were extracted for further investigation. Laser Raman spectroscopic analysis of a population of extracted graphite discs indicated that they experienced a maximum metamorphic temperature of 513 +/- 50 degrees C, which is consistent with the metamorphic grade of the host rock and supports their indigenicity. Scanning and transmission electron microscopy revealed that the particles bear morphological features (such as hexagonal sheets of graphite crystals) related to metamorphism and crystal growth, but a small fraction of them (graphite discs) are characterized by a circular morphology, distinct marginal concentric folds, surficial wrinkles, and complex nanostructures. Ion microprobe analysis of individual graphite discs showed that their carbon isotope compositions range from -7.4 per thousand to -35.9 per thousand V-PDB (Vienna Pee Dee Belemnite), with an average of -20.3 per thousand, which is comparable to bulk analysis of extracted carbonaceous material. The range of their size, ultrastructures, and isotopic signatures suggests that the morphology and geochemistry of the Wutai graphite discs were overprinted by metamorphism and their ultimate carbon source probably had diverse origins that included abiotic processes. We considered both biotic and abiotic origins of the carbon source and graphite disc morphologies and cannot falsify the possibility that some circular graphite discs characterized by marginal folds and surficial wrinkles represent deflated, compressed, and subsequently graphitized organic-walled vesicles. Together with reports by other authors of acanthomorphic acritarchs from greenschist-amphibolite-grade metamorphic rocks, this study suggests that it is worthwhile to examine carbonaceous materials preserved in highly metamorphosed rocks for possible evidence of ancient life.

3D X-ray ultra-microscopy of bone tissue.

PubMed

Langer, M; Peyrin, F

2016-02-01

We review the current X-ray techniques with 3D imaging capability at the nano-scale: transmission X-ray microscopy, ptychography and in-line phase nano-tomography. We further review the different ultra-structural features that have so far been resolved: the lacuno-canalicular network, collagen orientation, nano-scale mineralization and their use as basis for mechanical simulations. X-ray computed tomography at the micro-metric scale is increasingly considered as the reference technique in imaging of bone micro-structure. The trend has been to push towards increasingly higher resolution. Due to the difficulty of realizing optics in the hard X-ray regime, the magnification has mainly been due to the use of visible light optics and indirect detection of the X-rays, which limits the attainable resolution with respect to the wavelength of the visible light used in detection. Recent developments in X-ray optics and instrumentation have allowed to implement several types of methods that achieve imaging that is limited in resolution by the X-ray wavelength, thus enabling computed tomography at the nano-scale. We review here the X-ray techniques with 3D imaging capability at the nano-scale: transmission X-ray microscopy, ptychography and in-line phase nano-tomography. Further, we review the different ultra-structural features that have so far been resolved and the applications that have been reported: imaging of the lacuno-canalicular network, direct analysis of collagen orientation, analysis of mineralization on the nano-scale and use of 3D images at the nano-scale to drive mechanical simulations. Finally, we discuss the issue of going beyond qualitative description to quantification of ultra-structural features.

Two and three dimensional characterization of Zucchini Yellow Mosaic Virus induced structural alterations in Cucurbita pepo L. plants.

PubMed

Zellnig, Günther; Pöckl, Michael Herbert; Möstl, Stefan; Zechmann, Bernd

2014-05-01

Infection of plants by Zucchini Yellow Mosaic Virus (ZYMV) induces severe ultrastructural changes. The aim of this study was to investigate ultrastructural changes during ZYMV-infection in Cucurbita pepo L. plants on the two and three dimensional (2D and 3D) level and to correlate these changes with the spread of ZYMV throughout the plant by transmission electron microscopy (TEM) and image analysis. This study revealed that after inoculation of the cotyledons ZYMV moved into roots [3 days post inoculation (dpi)], then moved upwards into the stem and apical meristem (5 dpi), then into the first true leaf (7 dpi) and could finally be found in all plant parts (9 dpi). ZYMV-infected cells contained viral inclusion bodies in the form of cylindrical inclusions (CIs). These CIs occurred in four different forms throughout the cytosol of roots and leaves: scrolls and pinwheels when cut transversely and long tubular structures and bundles of filaments when cut longitudinally. 3D reconstruction of ZYMV-infected cells containing scrolls revealed that they form long tubes throughout the cytosol. The majority has a preferred orientation and an average length and width of 3 μm and 120 nm, respectively. Image analysis revealed an increased size of cells and vacuoles (107% and 447%, respectively) in younger ZYMV-infected leaves leading to a similar ratio of cytoplasm to vacuole (about 1:1) in older and younger ZYMV-infected leaves which indicates advanced cell growth in younger tissues. The collected data advances the current knowledge about ZYMV-induced ultrastructural changes in Cucurbita pepo. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Two and three dimensional characterization of Zucchini Yellow Mosaic Virus induced structural alterations in Cucurbita pepo L. plants

PubMed Central

Zellnig, Günther; Pöckl, Michael Herbert; Möstl, Stefan; Zechmann, Bernd

2014-01-01

Infection of plants by Zucchini Yellow Mosaic Virus (ZYMV) induces severe ultrastructural changes. The aim of this study was to investigate ultrastructural changes during ZYMV-infection in Cucurbita pepo L. plants on the two and three dimensional (2D and 3D) level and to correlate these changes with the spread of ZYMV throughout the plant by transmission electron microscopy (TEM) and image analysis. This study revealed that after inoculation of the cotyledons ZYMV moved into roots [3 days post inoculation (dpi)], then moved upwards into the stem and apical meristem (5 dpi), then into the first true leaf (7 dpi) and could finally be found in all plant parts (9 dpi). ZYMV-infected cells contained viral inclusion bodies in the form of cylindrical inclusions (CIs). These CIs occurred in four different forms throughout the cytosol of roots and leaves: scrolls and pinwheels when cut transversely and long tubular structures and bundles of filaments when cut longitudinally. 3D reconstruction of ZYMV-infected cells containing scrolls revealed that they form long tubes throughout the cytosol. The majority has a preferred orientation and an average length and width of 3 μm and 120 nm, respectively. Image analysis revealed an increased size of cells and vacuoles (107% and 447%, respectively) in younger ZYMV-infected leaves leading to a similar ratio of cytoplasm to vacuole (about 1:1) in older and younger ZYMV-infected leaves which indicates advanced cell growth in younger tissues. The collected data advances the current knowledge about ZYMV-induced ultrastructural changes in Cucurbita pepo. PMID:24631670

Craniopharyngioma: Survivin expression and ultrastructure

PubMed Central

ZHU, JIANG; YOU, CHAO

2015-01-01

The aim of the present study was to investigate the significance of survivin protein expression levels in craniopharyngioma. Tumor samples and clinical data were obtained from 50 patients with craniopharyngioma who were admitted to the West China Hospital of Sichuan University (Chengdu, China). The morphology of the craniopharyngioma samples was observed using optical and electron microscopes, and survivin expression was investigated in the samples by immunohistochemical analysis. The immunohistochemical results revealed survivin expression in all of the craniopharyngioma samples, but not in the healthy brain tissue samples. It was identified that survivin was expressed at a higher level in cases of the adamantinomatous type compared with those of the squamous-papillary type, in male patients compared with female patients, in children compared with adults and in recurrent cases compared with non-recurrent cases. Furthermore, no significant difference was detected in survivin expression levels among the tumors of different subtypes and different disease stages. The results of the present study indicate that survivin is significant in the development of craniopharyngioma, and that survivin protein expression levels are a meaningful indicator for assessing craniopharyngioma recurrence. PMID:25435936

Melasma treatment using an erbium:YAG laser: a clinical, immunohistochemical, and ultrastructural study.

PubMed

Attwa, Enayat; Khater, Mohamed; Assaf, Magda; Haleem, Manal Abdel

2015-02-01

Melasma is a common pigmentary disorder that remains resistant to available therapies. The aim of the present study was to evaluate the efficacy of erbium:YAG lasers in the treatment of refractory melasma and investigate the histopathological and ultrastructural changes between melasma skin and adjacent control skin before and after surgery. Fifteen Egyptian female patients with melasma unresponsive to previous therapy of bleaching creams and chemical peels were included in this study. Full-face skin resurfacing using an erbium:YAG laser was performed. Clinical parameters included physician and patient assessment, and melasma area and severity index score were done. Adverse effects after laser resurfacing were recorded. Biopsies of lesions and adjacent healthy skin were stained using hematoxylin-eosin, immunohistochemically marked for Melan-A, and evaluated by electron microscopy. The amount of melanin, staining intensity, and number of epidermal melanocytes are increased in melasma lesions as compared to normal skin. Electron microscopic analysis revealed an increased number of mature melanosomes in keratinocytes and melanocytes, with more marked cytoplasmic organelles in melasma skin than in biopsy specimens from normal skin, suggesting increased cell activity. After surgery, the number of melanocytes and concentration of melanin decreased in melasma skin, and the mean melasma area and severity index score decreased dramatically. Erbium:YAG laser resurfacing effectively improves melasma; however, the almost universal appearance of transient postinflammatory hyperpigmentation necessitates prompt and persistent intervention. © 2014 The International Society of Dermatology.

Flow cytometry application in the assessment of sperm DNA integrity of men with asthenozoospermia.

PubMed

Piasecka, M; Gaczarzewicz, D; Laszczyńska, M; Starczewski, A; Brodowska, A

2007-01-01

Sperm genomic integrity and ultrastructural features of ejaculated spermatozoa contributing to the assessment of gamete fertility potential in patients with asthenozoospermia are discussed. The proportion of TUNEL-positive cells was significantly higher in the semen of patients with low sperm motility (n=40; p<0.01) as compared to men with normal sperm motility (n=54). Sperm DNA fragmentation negatively correlated (n=94) with sperm motility, sperm concentration, and integrity of the sperm cellular membrane (HOS-test). Two categories of patients were distinguished: (1) patients (23 out of 94 subjects) with < or = 4% of TUNEL-positive cells and (2) patients (71 subjects) with 4% of TUNEL-positive cells. A significant difference was noted in the sperm motility and HOS-test results between patients from both groups. Large numbers of immature spermatozoa with extensive cytoplasmic retention, ultrastructural chromatin and midpiece abnormalities, and conglomerates containing sperm fragments were present more frequently in the semen of asthenozoospermic subjects with >4% of TUNEL-positive sperm cells. Low sperm motility seems to be accompanied by serious defects of gamete chromatin expressed as diminished sperm genomic integrity and abnormal DNA condensation and by defects of sperm midpiece. These abnormalities may reflect developmental failure during the spermatogenic remodeling process. The DNA fragmentation test may be considered as an additional assay for the evaluation of spermatozoa beside standard analysis and taken together with electron microscopy may help to determine the actual number of "healthy" spermatozoa thereby playing an important role during diagnosis and treatment of male infertility.

Ultrastructural analysis and polymorphisms in Coarazuphium caatinga (Coleoptera: Carabidae: Zuphiini), a new Brazilian troglobitic beetle.

PubMed

Pellegrini, Thais Giovannini; Ferreira, Rodrigo Lopes

2014-02-21

Coarazuphium caatinga sp. n. occurs in limestone caves located in Campo Formoso municipality, in the Brazilian Caatinga (Bahia, Brazil). The new species is close to C. formoso although they are morphologically distinct by the elytra sinuosity, which is more pronounced in C. caatinga; the aedeagus is more tapered at the tip in this last species. Important traits found in C. caatinga are the variable size presented by the eyes, and the remarkable variability of body pigmentation among specimens; both traits do not seem to be correlated. Coarazuphium Gnaspini, P., Vanin, S.A. & Godoy, N.M., 1998, species exhibit advanced troglomorphic characters in comparison to other Brazilian cave beetles, as are increased extra-optic sensory structures, presence of particular sensilla, and sensory and gustatory receptors. These characters are not detected under routine microscopy and thus require ultrastructural methods for their study.

Mobilifilum chasei: morphology and ecology of a spirochete from an intertidal stratified microbial mat community

NASA Technical Reports Server (NTRS)

Margulis, L.; Hinkle, G.; Stolz, J.; Craft, F.; Esteve, I.; Guerrero, R.

1990-01-01

Spirochetes were found in the lower anoxiphototrophic layer of a stratified microbial mat (North Pond, Laguna Figueroa, Baja California, Mexico). Ultra-structural analysis of thin sections of field samples revealed spirochetes approximately 0.25 micrometer in diameter with 10 or more periplasmic flagella, leading to the interpretation that these spirochetes bear 10 flagellar insertions on each end. Morphometric study showed these free-living spirochetes greatly resemble certain symbiotic ones, i.e., Borrelia and certain termite spirochetes, the transverse sections of which are presented here. The ultrastructure of this spirochete also resembles Hollandina and Diplocalyx (spirochetes symbiotic in arthropods) more than it does Spirochaeta, the well known genus of mud-dwelling spirochetes. The new spirochete was detected in mat material collected both in 1985 and in 1987. Unique morphology (i.e., conspicuous outer coat of inner membrane, large number of periplasmic flagella) and ecology prompt us to name a new free-living spirochete.

Ultrastructural Changes in Human Striated Muscle Using Three Methods of Training

ERIC Educational Resources Information Center

Penman, Kenneth A.

1969-01-01

There have been many attempts to describe what happens when a muscle gets stronger. However, little has been done to examine possible structural changes at the ultrastructural level when a muscle becomes stronger or hypertrophied. (CK)

Acute Exposure of Medaka to Carcinogens: An Ultrastructural, Cytochemical and Morphometric Analysis of Liver and Kidney

DTIC Science & Technology

1993-05-20

statements regarding acid phosphatase activity are not possible because of the inconsistency of labeling. Morphometric analysis were conducted on ratios of...may result from the combining of TCE and other toxic substances. The two enzyme systems selected for examination, acid phosphatase and peroxidase are...administration of DENA have demonstrated altered activity of several enzymes, including acid phosphatase (Fischer et al., 1983). Long term treatment of rodents

Effects of management in gestational diabetes mellitus with normal prepregnancy body mass index on pregnancy outcomes and placental ultrastructures: a prospective cohort study.

PubMed

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 < 0.01). The incidences of fetal distress, cesarean section and large for gestational age were significantly lower in intervention group than in control group (P < 0.05). There was a significant reduction in the incidence of abnormal placental ultrastructure in the intervention group (P < 0.01). After adjustment for confounding factors, the undesirable glycemic control and conventional management were related to abnormal placental ultrastructure (P < 0.05). Meanwhile, the undesirable glycemic control, abnormal placental ultrastructure and conventional management made sense in the incidence of fetal distress (P < 0.05), and the target glycemic control, recommend weight gain and active management were associated with reductions in the prevalence of cesarean delivery and large for gestational age (P < 0.05). The active management of 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.

Histology and surface ultrastructure during early healing after gingival augmentation with a three-dimensional collagen matrix: A report of six cases.

PubMed

Rusu, Darian; Stratul, Stefan-Ioan; Festila, Dana; Surlin, Petra; Kasaj, Adrian; Baderca, Flavia; Boariu, Marius; Jentsch, Holger; Locovei, Cosmin; Calenic, Bogdan

2017-01-01

The objective of the present case series is to describe the histology and surface ultrastructure of augmented keratinized gingival mucosa in humans during the early healing phase after surgical placement of a xenogeneic collagen matrix. Six patients underwent surgical augmentation of keratinized tissue by placement of a three-dimensional (3D) xenogeneic collagen matrix. Full-depth mucosal biopsies including original attached gingiva, augmented gingiva, and the separation zone were performed at baseline and at postoperative days 7 and 14. The specimens were stained with hematoxylin-eosin, Masson-trichrome, picrosirius red, and Papanicolaou's trichrome. Low-vacuum scanning electron microscopy (SEM) surface analysis was correlated with histology. The separation zone was clearly visible upon histologic and SEM examination at 7 days. The portions of augmented mucosa consisted of well-structured, immature gingival tissue with characteristics of per secundam healing underlying a completely detached amorphous collagenous membrane-like structure of approximately 100 μm thick. At 14 days, histologic and ultrastructural examinations showed an almost complete maturation process. There were no detectable remnants of the collagen matrix within the newly formed tissues at either time point. Within their limits the results suggest that the 3D collagen matrix appears to play an indirect role during the early phase of wound healing by protecting the newly formed underlying tissue and guiding the epithelialization process.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kloc, Malgorzata; Bilinski, Szczepan; Dougherty, Matthew T.

2007-05-01

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 andmore » 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.« less

Electron microscopy of human peripheral nerves of clinical relevance to the practice of nerve blocks. A structural and ultrastructural review based on original experimental and laboratory data.

PubMed

Reina, M A; Arriazu, R; Collier, C B; Sala-Blanch, X; Izquierdo, L; de Andrés, J

2013-12-01

The goal is to describe the ultrastructure of normal human peripheral nerves, and to highlight key aspects that are relevant to the practice of peripheral nerve block anaesthesia. Using samples of sciatic nerve obtained from patients, and dural sac, nerve root cuff and brachial plexus dissected from fresh human cadavers, an analysis of the structure of peripheral nerve axons and distribution of fascicles and topographic composition of the layers that cover the nerve is presented. Myelinated and unmyelinated axons, fascicles, epineurium, perineurium and endoneurium obtained from patients and fresh cadavers were studied by light microscopy using immunohistochemical techniques, and transmission and scanning electron microscopy. Structure of perineurium and intrafascicular capillaries, and its implications in blood-nerve barrier were revised. Each of the anatomical elements is analyzed individually with regard to its relevance to clinical practice to regional anaesthesia. Routine practice of regional anaesthetic techniques and ultrasound identification of nerve structures has led to conceptions, which repercussions may be relevant in future applications of these techniques. In this regard, the ultrastructural and histological perspective accomplished through findings of this study aims at enlightening arising questions within the field of regional anaesthesia. Copyright © 2013 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Published by Elsevier España. All rights reserved.

Cyanobacterial composition of microbial mats from an Australian thermal spring: a polyphasic evaluation.

PubMed

McGregor, Glenn B; Rasmussen, J Paul

2008-01-01

Cyanobacterial composition of microbial mats from an alkaline thermal spring issuing at 43-71 degrees C from tropical north-eastern Australia are described using a polyphasic approach. Eight genera and 10 species from three cyanobacterial orders were identified based on morphological characters. These represented taxa previously known as thermophilic from other continents. Ultrastructural analysis of the tower mats revealed two filamentous morphotypes contributed the majority of the biomass. Both types had ultrastructural characteristics of the family Pseudanabaenaceae. DNA extracts were made from sections of the tentaculiform towers and the microbial community analysed by 16S cyanobacteria-specific PCR and denaturing-gradient gel electrophoresis. Five significant bands were identified and sequenced. Two bands clustered closely with Oscillatoria amphigranulata isolated from New Zealand hot springs; one unique phylotype had only moderate similarity to a range of Leptolyngbya species; and one phylotype was closely related to a number of Geitlerinema species. Generally the approaches yielded complementary information, however the results suggest that species designation based on morphological and ultrastructural criteria alone often fails to recognize their true phylogenetic position. Conversely some molecular techniques may fail to detect rare taxa suggesting that the widest possible suite of techniques be applied when conducting analyses of cyanobacterial diversity of natural populations. This is the first polyphasic evaluation of thermophilic cyanobacterial communities from the Australian continent.

Synaptic plasticity and gravity: Ultrastructural, biochemical and physico-chemical fundamentals

NASA Astrophysics Data System (ADS)

Rahmann, H.; Slenzka, K.; Körtje, K. H.; Hilbig, R.

On the basis of quantitative disturbances of the swimming behaviour of aquatic vertebrates (``loop-swimming'' in fish and frog larvae) following long-term hyper-g-exposure the question was raised whether or not and to what extent changes in the gravitational vector might influence the CNS at the cellular level. Therefore, by means of histological, histochemical and biochemical analyses the effect of 2-4 x g for 9 days on the gross morphology of the fish brain, and on different neuronal enzymes was investigated. In order to enable a more precise analysis in future-μg-experiments of any gravity-related effects on the neuronal synapses within the gravity-perceptive integration centers differentiated electron-microscopical and electronspectroscopical techniques have been developed to accomplish an ultrastructural localization of calcium, a high-affinity Ca2+-ATPase, creatine kinase and cytochrome oxidase. In hyper-g animals vs. 1-g controls, a reduction of total brain volume (15 %), a decrease in creatine kinase activity (20 %), a local increase in cytochrome oxidase activity, but no differences in Ca2+/Mg2+-ATPase activities were observed. Ultrastructural peculiarities of synaptic contact formation in gravity-related integration centers (Nucleus magnocellularis) were found. These results are discussed on the basis of a direct effect of hyper-gravity not only on the gravity-sensitive neuronal integration centers but possibly also on the physico-chemical properties of the lipid bilayer of neuronal membranes in general.

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

PubMed

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 evaluation of multiple pass low energy versus single pass high energy radio-frequency treatment.

PubMed

Kist, David; Burns, A Jay; Sanner, Roth; Counters, Jeff; Zelickson, Brian

2006-02-01

The radio-frequency (RF) device is a system capable of volumetric heating of the mid to deep dermis and selective heating of the fibrous septa strands and fascia layer. Clinically, these effects promote dermal collagen production, and tightening of these deep subcutaneous structures. A new technique of using multiple low energy passes has been described which results in lower patient discomfort and fewer side effects. This technique has also been anecdotally described as giving more reproducible and reliable clinical results of tissue tightening and contouring. This study will compare ultrastructural changes in collagen between a single pass high energy versus up to five passes of a multiple pass lower energy treatment. Three subjects were consented and treated in the preauricular region with the RF device using single or multiple passes (three or five) in the same 1.5 cm(2) treatment area with a slight delay between passes to allow tissue cooling. Biopsies from each treatment region and a control biopsy were taken immediately, 24 hours or 6 months post treatment for electron microscopic examination of the 0-1 mm and 1-2 mm levels. Sections of tissue 1 mm x 1 mm x 80 nm were examined with an RCA EMU-4 Transmission Electron Microscope. Twenty sections from 6 blocks from each 1 mm depth were examined by 2 blinded observers. The morphology and degree of collagen change in relation to area examined was compared to the control tissue, and estimated using a quantitative scale. Ultrastructural examination of tissue showed that an increased amount of collagen fibril changes with increasing passes at energies of 97 J (three passes) and 122 J (five passes), respectively. The changes seen after five multiple passes were similar to those detected after much more painful single pass high-energy treatments. This ultrastructural study shows changes in collagen fibril morphology with an increased effect demonstrated at greater depths of the skin with multiple low-fluence passes and at lesser depths with single pass higher fluence settings. Findings suggest that similar collagen fibril alteration can occur with multiple pass low-energy treatments and single pulse high-energy treatments. The lower fluence multiple pass approach is associated with less patient discomfort, less side effects, and more consistent clinical results. Copyright 2005 Wiley-Liss, Inc.

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

PubMed

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.

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

PubMed

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.

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

PubMed

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.

[Silymarin in pregnancy and during hormonal contraceptive treatment. Blood chemistry and ultrastructural findings in the experimental model].

PubMed

Martines, G; Piva, M; Copponi, V; Cagnetta, G

1979-01-01

Further systematic study of the relation between drugs and the ultrastructure of the liver is reported with regard to the experimental administration of silimarin to pregnant women and others on the pill. Marked signs of ultrastructural alteration of the REL and biliary cell pole were noted, matched, by evidence of throbophilia and changes in protein activity and lipid synthesis, are noted in these situations, but not when suitable doses of silimarine are taken with the pill. It is suggested that silimarin may prevent and correct liver damage during pregnancy and the administration of oestroprogestins.

The effects of high-power microwaves on the ultrastructure of Bacillus subtilis.

PubMed

Kim, S-Y; Jo, E-K; Kim, H-J; Bai, K; Park, J-K

2008-07-01

To investigate the microbicidal mechanisms of high-power microwave (2.0 kW) irradiation on Bacillus subtilis and to determine the effect of this procedure on the ultrastructure of the cell wall. We performed viability test, examined cells using transmission electron microscopy (TEM), and measured the release of intracellular proteins and nucleic acids. The inactivation rate of B. subtilis by 2.0-kW microwave irradiation was higher than that of a domestic microwave (0.5 kW). Few proteins were released from either microwaved or boiled cells. However, the leakage of nucleic acids from 2.0-kW-microwaved cells was significantly higher than that of 0.5-kW-microwaved or boiled cells. Therefore, we examined ultrastructural alterations of microwaved or boiled cells to analyse the pattern of release of cytoplasmic contents. Although boiled cells did not show any ultrastructural changes on TEM, 2.0-kW-microwaved cells showed disruption of the cell wall. The microbicidal mechanisms of 2.0-kW microwave irradiation include damage to the microbial cell wall, breakage of the genomic DNA, and thermal coagulation of cytoplasmic proteins. TEM images showed that the cytoplasmic protein aggregation and cell envelope damage by microwave irradiation were different from the ultrastructural changes observed after boiling.

[Effect of bitumen fume on neurotransmitter and ultrastructure in mice brain].

PubMed

Li, Hai-Ling; Guo, Xiang-Yun; Feng, San-Wei; Liu, Chang-Hai

2006-12-01

To observe the effects of bitumen fume on neurotransmitter and ultrastructure of mice brain and to investigate the toxicity of bitumen fume on nerve system of mice brain. The experimental mice were forced to inhale the bitumen fume at different exposure level and in different time periods. The contents of the three transmitters dopamine (DA), norepinephrine (NE), 5-hydroxytryptamine (5-HT) in mice brain were measured by the fluorescence meanwhile ultrastructure of mice brain was observed by electronic microscope. The ultrastructure of mice brain was observed under transmission electron microscopy. The contents of DA, NE and 5-HT in all groups decreased with the increasing of dose and prolonging of time (after 8 week, with the increasing of exposure lever, the content of DA, NE, 5-HT was respectively 2.194, 2.190, 2.181, 2.178 microg/g and 1.148, 1.138, 1.135 and 1.407, 1.403, 1.395 microg), but the results did not show significant differences. The structure of the mitochondria changes included the swollen mitochondria, chromatin margination, pyknosis and apoptosis in neuro cells and the processes of swollen astrocyte cells. The bitumen fume could induce changes of the ultrastructure of mice brain and affect the contents of neurotransmitter of mice brain.

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

PubMed

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 Chinese Leishmania sp. is in close relationship with reptilian Leishmania.

Ultrastructural characteristics of some bacteria after treatment with Lubrol W.

PubMed

Cherepova, N; Spasova, D

1994-01-01

Specific ultrastructural changes occurred mainly in the cell wall and cytoplasmic membrane of Listeria monocytogenes, Salmonella typhimurium, Pseudomonas pseudomallei and Pseudomonas aeruginosa bacteria when treated with 0.5% and 1% Lubrol W1 by means of transmission and scanning electron microscopy.

Malignant lymphoma of the cervix uteri: histology and ultrastructure.

PubMed Central

Carr, I; Hill, A S; Hancock, B; Neal, F F

1976-01-01

Two cases of primary lymphoma of the cervix uteri are described. Both responded to radiotherapy; both were composed at the ultrastructural level of mature macrophages and immature, apparently neoplastic lymphoreticular cells and are classified as reticulum cell lymphoma. Images PMID:783205

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

PubMed

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.

Trachyrhizium urniformis n. g., n. sp., a Novel Marine Filose Thecate Amoeba Related to a Cercozoan Environmental Clade (Novel Clade 4).

PubMed

Shiratori, Takashi; Ishida, Ken-Ichiro

2016-11-01

A novel cercozoan filose thecate amoeba, Trachyrhizium urniformis n. g., n. sp., was isolated from a marine sediment sample collected at Agenashiku Island, Okinawa, Japan. We performed light and electron microscopic observations, and a molecular phylogenetic analysis using the small subunit ribosomal RNA gene of the isolate. Cells of T. urniformis are spherical in shape and are covered by a thin theca possessing a wide rounded aperture. Branching and occasionally anastomosing filopodia with small granules emerge from the aperture. The granules are transported in the filopodia bidirectionally. Transmission electron microscopy showed that cells of T. urniformis possess nucleus with permanently condensed chromatin, Golgi apparatuses, microbodies, mitochondria with tubular cristae, and extrusomes. Several morphological and ultrastructural features of T. urniformis (the presence of thecae and nucleus with permanently condensed chromatin) show similarities with those of Thecofilosea. In a phylogenetic analysis, T. urniformis included in Thecofilosea with weak statistical supports and formed a clade with two sequences that constitutes a cercozoan environmental clade, novel clade 4. On the basis of morphological and ultrastructural information and the results of the phylogenetic analysis, we propose T. urniformis as a new member of class Thecofilosea. © 2016 The Author(s) Journal of Eukaryotic Microbiology © 2016 International Society of Protistologists.

Three-dimensional analysis of synapses in the transentorhinal cortex of Alzheimer's disease patients.

PubMed

Domínguez-Álvaro, M; Montero-Crespo, M; Blazquez-Llorca, L; Insausti, R; DeFelipe, J; Alonso-Nanclares, L

2018-03-02

Synaptic dysfunction or loss in early stages of Alzheimer's disease (AD) is thought to be a major structural correlate of cognitive dysfunction. Early loss of episodic memory, which occurs at the early stage of AD, is closely associated with the progressive degeneration of medial temporal lobe (MTL) structures of which the transentorhinal cortex (TEC) is the first affected area. However, no ultrastructural studies have been performed in this region in human brain samples from AD patients. In the present study, we have performed a detailed three-dimensional (3D) ultrastructural analysis using focused ion beam/scanning electron microscopy (FIB/SEM) to investigate possible synaptic alterations in the TEC of patients with AD. Surprisingly, the analysis of the density, morphological features and spatial distribution of synapses in the neuropil showed no significant differences between AD and control samples. However, light microscopy studies showed that cortical thickness of the TEC was severely reduced in AD samples, but there were no changes in the volume occupied by neuronal and glial cell bodies, blood vessels, and neuropil. Thus, the present results indicate that there is a dramatic loss of absolute number of synapses, while the morphology of synaptic junctions and synaptic spatial distribution are maintained. How these changes affect cognitive impairment in AD remains to be elucidated.

Ultrastructural changes in sweet orange with symptoms of huanglongbing

USDA-ARS?s Scientific Manuscript database

Citrus greening (Huanglongbing [HLB]) is one of the most destructive citrus diseases worldwide. To better understand the ultrastructural changes of sweet orange seedlings in response to infection, anatomical analyses of HLB-infected sweet orange were carried out by light and electron microscopy. A...

Protection of ultrastructure in chilling-stressed banana leaves by salicylic acid*

PubMed Central

Kang, Guo-zhang; Wang, Zheng-xun; Xia, Kuai-fei; Sun, Gu-chou

2007-01-01

Objective: Chilling tolerance of salicylic acid (SA) in banana seedlings (Musa acuminata cv., Williams 8818) was investigated by changes in ultrastructure in this study. Methods: Light and electron microscope observation. Results: Pretreatment with 0.5 mmol/L SA under normal growth conditions (30/22 °C) by foliar spray and root irrigation resulted in many changes in ultrastructure of banana cells, such as cells separation from palisade parenchymas, the appearance of crevices in cell walls, the swelling of grana and stromal thylakoids, and a reduction in the number of starch granules. These results implied that SA treatment at 30/22 °C could be a type of stress. During 3 d of exposure to 7 °C chilling stress under low light, however, cell ultrastructure of SA-pretreated banana seedlings showed less deterioration than those of control seedlings (distilled water-pretreated). Conclusion: SA could provide some protection for cell structure of chilling-stressed banana seedling. PMID:17444604

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

NASA Astrophysics Data System (ADS)

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

2011-05-01

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.

Ultrastructure of sea urchin calcified tissues after high-pressure freezing and freeze substitution.

PubMed

Ameye, L; Hermann, R; Dubois, P

2000-08-01

The improvements brought by high-pressure freezing/freeze substitution fixation methods to the ultrastructural preservation of echinoderm mineralized tissues are investigated in developing pedicellariae and teeth of the echinoid Paracentrotus lividus. Three freeze substitution (FS) protocols were tested: one in the presence of osmium tetroxide, one in the presence of uranyl acetate, and the last in the presence of gallic acid. FS in the presence of osmium tetroxide significantly improved cell ultrastructure preservation and should especially be used for ultrastructural studies involving vesicles and the Golgi apparatus. With all protocols, multivesicular bodies, suggested to contain Ca(2+), were evident for the first time in skeleton-forming cells. FS in the presence of gallic acid allowed us to confirm the structured and insoluble character of a part of the organic matrix of mineralization in the calcification sites of the tooth, an observation which modifies the current understanding of biomineralization control in echinoderms. Copyright 2000 Academic Press.

Pravastatin reduces Marfan aortic dilation.

PubMed

McLoughlin, Darren; McGuinness, Jonathan; Byrne, John; Terzo, Eloisa; Huuskonen, Vilhelmiina; McAllister, Hester; Black, Alexander; Kearney, Sinead; Kay, Elaine; Hill, Arnold D K; Dietz, Harry C; Redmond, J Mark

2011-09-13

The sequelae of aortic root dilation are the lethal consequences of Marfan syndrome. The root dilation is attributable to an imbalance between deposition of matrix elements and metalloproteinases in the aortic medial layer as a result of excessive transforming growth factor-beta signaling. This study examined the efficacy and mechanism of statins in attenuating aortic root dilation in Marfan syndrome and compared effects to the other main proposed preventative agent, losartan. Marfan mice heterozygous for a mutant allele encoding a cysteine substitution in fibrillin-1 (C1039G) were treated daily from 6 weeks old with pravastatin 0.5 g/L or losartan 0.6 g/L. The end points of aortic root diameter (n=25), aortic thickness, and architecture (n=10), elastin volume (n=5), dp/dtmax (maximal rate of change of pressure) (cardiac catheter; n=20), and ultrastructural analysis with stereology (electron microscopy; n=5) were examined. The aortic root diameters of untreated Marfan mice were significantly increased in comparison to normal mice (0.161 ± 0.001 cm vs 0.252 ± 0.004 cm; P<0.01). Pravastatin (0.22 ± 0.003 cm; P<0.01) and losartan (0.221 ± 0.004 cm; P<0.01) produced a significant reduction in aortic root dilation. Both drugs also preserved elastin volume within the medial layer (pravastatin 0.23 ± 0.02 and losartan 0.29 ± 0.03 vs untreated Marfan 0.19 ± 0.02; P=0.01; normal mice 0.27 ± 0.02). Ultrastructural analysis showed a reduction of rough endoplasmic reticulum in smooth muscle cells with pravastatin (0.022 ± 0.004) and losartan (0.013 ± 0.001) compared to untreated Marfan mice (0.035 ± 0.004; P<0.01). Statins are similar to losartan in attenuating aortic root dilation in a mouse model of Marfan syndrome. They appear to act through reducing the excessive protein manufacture by vascular smooth muscle cells, which occurs in the Marfan aorta. As a drug that is relatively well-tolerated for long-term use, it may be useful clinically.

Electron microscopic examination of the myelinated axons of corpus callosum in perfused young and old rats.

PubMed

Sargon, Mustafa F; Denk, C Cem; Celik, H Hamdi; Surucu, H Selcuk; Aldur, M Mustafa

2007-07-01

In this study, the myelinated axons of parts of the corpus callosums of young and old rats were examined under the electron microscope and a grading system was performed for quantitating the ultrastructural pathological changes of these axons. Except the old splenium group, the only ultrastructural pathological change, observed in the myelinated axons was the separation in myelin configuration. In addition to this finding, in the old splenium group, in some of the myelinated axons, an interruption was observed in the myelin configuration. Additionally, these ultrastructural pathological findings were present in the larger sized myelinated axons of the corpus callosum.

Evaluation of ultrastructural hepatic response to environmental toxicants in wild cotton rats (Sigmodon hispidus)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elangbam, C.S.; Qualls, C.W.; Confer, A.W.

1991-08-01

Hepatic lobules are composed of hepatocytes organized in three microcirculatory zones (periportal, midzonal, and centrilobular). The hepatocytes in each of these zones contain enzymes which are involved in various biochemical reactions. The predominant location of the mixed-function oxidation system in the liver lobule is the centrilobular zone. Ultrastructural changes in the hepatocytes not only correlate with biochemical events of detoxification but also with toxic effects of a parent compound or its metabolites. The objectives of this study was to characterize the ultrastructural alterations in the liver of wild cotton rats (Sigmodon hispidus) following exposure to polychlorinated biphenyls (PCB) contaminated habitat.

Ultrastructural markers of lymph nodes in patients with acquired immune deficiency syndrome and in homosexual males with unexplained persistent lymphadenopathy. A quantitative study.

PubMed

Onerheim, R M; Wang, N S; Gilmore, N; Jothy, S

1984-09-01

To determine if vesicular rosettes (VR), tubuloreticular structures (TRS), and "test-tube and ring-shaped forms" (TRF) are characteristic ultrastructural features of the syndromes of acquired immune deficiency (AIDS) or of unexplained persistent lymphadenopathy (PLS), the authors studied lymph nodes from nine patients with PLS, two patients with AIDS, and seven controls by electron microscopy. An average of 122 lymphocytes per case were photographed. VR were present in only 0.37% of lymphocytes in 4 of 11 index cases and were mimicked by grouped vesicles and degenerating multivesicular bodies (MVB). TRS were found in 10 of 11 index cases, compared with only one of seven controls (P less than 0.01). In the index cases, they were more frequent in AIDS (mean 21%) than in PLS lymphocytes (mean 4%) (P less than 0.05). MVB were found in all index cases and five of seven controls and were more frequent in index lymphocytes (mean 19%) than in controls (mean 5%) (P less than 0.01). TRF were found in one Haitian male with AIDS, where they were present in 4% of lymphocytes. VR are infrequent and indistinct. MVB probably reflect the reactivity of the lymphocytes. TRF is not a feature of PLS. The authors conclude that there are no pathognomonic ultrastructural markers of AIDS or PLS but that TRS are characteristic of both syndromes and occur frequently enough to be supportive to the diagnosis of AIDS and PLS.

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

PubMed

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.

Pathogenesis of trimethyltin neuronal toxicity. Ultrastructural and cytochemical observations.

PubMed Central

Bouldin, T. W.; Goines, N. D.; Bagnell, R. C.; Krigman, M. R.

1981-01-01

The ultrastructural cytopathologic and cytochemical effects of trimethyltin (TMT) neurotoxicity were delineated in hippocampal and pyriform neurons of acutely intoxicated adult rats. TMT produced neuronal necrosis that preferentially involved hippocampal formation pyriform cortex. The first subcellular alterations were multifocal collection of dense-cored vesicles and tubules and membrane-delimited vacuoles in the cytoplasm of the perikaryon and proximal dendrite. Ultrastructural cytochemical examination revealed that the vesicles and tubules had acid phosphatase activity analagous to Golgi-associated endoplasmic reticulum (GERL). Shortly after the appearance of the GERL-like vesicles and tubules, autophagic vacuoles and polymorphic dense bodies accumulated in the neuronal cytoplasm. Some dense bodies appeared to arise from the dense-cored tubules. Neuronal necrosis was characterized by increased electron density of the cytoplasm and large, electron-dense intranuclear masses. Alterations of mitochondria and other organelles were not observed in the early stages of cell injury. No light- or electron-microscopic alterations were found in liver or kidney. Comparable subcellular alterations were observed in adult and neonatal rats chronically intoxicated with TMT. A series of other trialkyl and tricyclic tins and dimethyltin did not produce similar pathologic findings. The GERL-like accumulations are unique in neuronal cytopathology. These findings suggests that GERL and autophagy play an important role in the pathogenesis of TMT-induced neuronal injury. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 PMID:7294153

Detection of ultrastructural changes in genetically altered and exercised skeletal muscle using PS-OCT

NASA Astrophysics Data System (ADS)

Pasquesi, James J.; Schlachter, Simon C.; Boppart, Marni D.; Chaney, Eric; Kaufman, Stephen J.; Boppart, Stephen A.

2006-02-01

Birefringence of skeletal muscle has been associated with the ultrastructure of individual sarcomeres, specifically the arrangement of A-bands corresponding to the thick myosin filaments. Murine skeletal muscle (gastrocnemius) was imaged with a fiber-based PS-OCT imaging system to determine the level of birefringence present in the tissue under various conditions. In addition to muscle controls from wild-type mice, muscle from abnormal mice included: genetically-modified (mdx) mice which model human muscular dystrophy, transgenic mice exhibiting an overexpression of integrin (α7β1), and transgenic integrin (α7β1)knockout mice. Comparisons were also made between rested and exercised muscles to determine the effects of exercise on muscle birefringence for each of these normal and abnormal conditions. The PS-OCT images revealed that the presence of birefringence was similar in the rested muscle with dystrophy-like features (i.e., lacking the structural protein dystrophin - mdx) and in the integrin (α7β1)knockout muscle when compared to the normal (wild-type) control. However, exercising these abnormal muscle tissues drastically reduced the presence of birefringence detected by the PS-OCT system. The muscle exhibiting an overexpression of integrin (α7β1) remained heavily birefringent before and after exercise, similar to the normal (wild-type) muscle. These results suggest that there is a distinct relationship between the degree of birefringence detected using PS-OCT and the sarcomeric ultrastructure present within skeletal muscle.

Low-intensity vibrations normalize adipogenesis-induced morphological and molecular changes of adult mesenchymal stem cells.

PubMed

Baskan, Oznur; Mese, Gulistan; Ozcivici, Engin

2017-02-01

Bone marrow mesenchymal stem cells that are committed to adipogenesis were exposed daily to high-frequency low-intensity mechanical vibrations to understand molecular, morphological and ultrastructural adaptations to mechanical signals during adipogenesis. D1-ORL-UVA mouse bone marrow mesenchymal stem cells were cultured with either growth or adipogenic medium for 1 week. Low-intensity vibration signals (15 min/day, 90 Hz, 0.1 g) were applied to one group of adipogenic cells, while the other adipogenic group served as a sham control. Cellular viability, lipid accumulation, ultrastructure and morphology were determined with MTT, Oil-Red-O staining, phalloidin staining and atomic force microscopy. Semiquantitative reverse transcription polymerase chain reaction showed expression profile of the genes responsible for adipogenesis and ultrastructure of cells. Low-intensity vibration signals increased viability of the cells in adipogenic culture that was reduced significantly compared to quiescent controls. Low-intensity vibration signals also normalized the effects of adipogenic condition on cell morphology, including area, perimeter, circularization and actin cytoskeleton. Furthermore, low-intensity vibration signals reduced the expression of some adipogenic markers significantly. Mesenchymal stem cells are sensitive and responsive to mechanical loads, but debilitating conditions such as aging or obesity may steer mesenchymal stem cells toward adipogenesis. Here, daily application of low-intensity vibration signals partially neutralized the effects of adipogenic induction on mesenchymal stem cells, suggesting that these signals may provide an alternative and/or complementary option to reduce fat deposition.

Immunocytochemical and ultrastructural identification of pituitary cell types in the protogynous Thalassoma duperrey during adult sexual ontogeny

USGS Publications Warehouse

Parhar, I.S.; Nagahama, Y.; Grau, E.G.; Ross, R.M.

1998-01-01

Protogynous wrasses (Thalassoma duperrey): females (F), primary males (PM) along with a few terminal-phase males (TM) and sex-changed males (SM), were used to characterize the topographical organization of the pituitary. In general, immunocytochemical and ultrastructural features of the adenohypophyseal cell types of the saddleback wrasse pituitary resemble those of other teleosts. In the rostral pars distalis (RPD), corticotropic cells were found bordering the neurohypophysis (NH) and surrounding the centroventrally located prolactin cells. Thyrotropic cells formed a small group in the anteriodorsal part of the rostral and proximal pars distalis (PPD). The somatotropic cells were distributed in large clusters, mostly organized in cell cords around the interdigitations of the NH of the dorsal PPD. Cells containing gonadotropin I?? subunit were localized in the dorsal parts of the PPD, in close association with somatotropic cells and gonadotropin II?? subunit containing cells were seen in the centroventral parts of the PPD and along the periphery of the pars intermedia (PI). The pars intermedia was composed of melanotropic cells and somatolactin cells that lined the neurohypohysis. Distinct ultrastructural differences in corticotropic and somatotropic cells were not observed between the four groups. In all groups, prolactin cells in the ventral-most RPD could be immature cells or actively secreting prolactin. Gonadotropic II cells of PM and F had relatively higher incidence of "nuclear budding" and cell organelles compared to TM and SM. Besides gonadotropic, the active melanotropic and somatolactin cells might be associated with some aspect(s) of reproduction.

Effect of Egg Washing and Correlation between Eggshell Characteristics and Egg Penetration by Various Salmonella Typhimurium Strains

PubMed Central

Gole, Vaibhav C.; Chousalkar, Kapil K.; Roberts, Juliet R.; Sexton, Margaret; May, Damian; Tan, Jessica; Kiermeier, Andreas

2014-01-01

Salmonella is an important foodborne pathogen, causing an estimated 11,992 cases of infection in Australia per year. Egg or egg product related salmonellosis is a major concern for the egg industry. Worldwide, S. Typhimurium is one of the most common serovars identified in Salmonella food poisoning cases. The current study investigated the ability of five S. Typhimurium strains to penetrate washed and unwashed eggs using whole egg and agar egg penetration methods. All S. Typhimurium strains were able to penetrate eggshells and survive in egg albumen (at 20°C) according to whole egg penetration results. Polymerase Chain Reaction results demonstrated that S. Typhimurium strain 2 (103 and 105 CFU/mL), and strain 5 (103 and 105 CFU/mL) egg penetration was significantly higher (p<0.05) in washed eggs when compared to unwashed eggs. Statistical analysis of the agar penetration experiment indicated that S. Typhimurium was able to penetrate washed eggs at a significantly higher rate when compared to unwashed eggs (p<0.05). When compared to unwashed eggs, washed eggs also had significantly damaged cuticles. Statistical analysis also indicated that eggshell penetration by S. Typhimurium was related to various eggshell ultrastructural features such as cap quality, alignment, erosion, confluence, Type B bodies and cuticle cover. PMID:24621821

Proteomic analysis of the renal effects of simulated occupational jet fuel exposure.

PubMed

Witzmann, F A; Bauer, M D; Fieno, A M; Grant, R A; Keough, T W; Lacey, M P; Sun, Y; Witten, M L; Young, R S

2000-03-01

We analyzed protein expression in the cytosolic fraction prepared from whole kidneys in male Swiss-Webster mice exposed 1 h/day for five days to aerosolized JP-8 jet fuel at a concentration of 1000 mg/m3, simulating military occupational exposure. Kidney cytosol samples were solubilized and separated via large-scale, high-resolution two-dimensional electrophoresis (2-DE) and gel patterns scanned, digitized and processed for statistical analysis. Significant changes in soluble kidney proteins resulted from jet fuel exposure. Several of the altered proteins were identified by peptide mass finger-printing and related to ultrastructural abnormalities, altered protein processing, metabolic effects, and paradoxical stress protein/detoxification system responses. These results demonstrate a significant but comparatively moderate JP-8 effect on protein expression in the kidney and provide novel molecular evidence of JP-8 nephrotoxicity. Human risk is suggested by these data but conclusive assessment awaits a noninvasive search for biomarkers in JP-8 exposed humans.

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

PubMed

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.

Form follows function: ultrastructure of different morphotypes of Physarum polycephalum

NASA Astrophysics Data System (ADS)

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.

[Effects of N-butylphthalide on the expressions of ZO-1 and claudin-5 in blood-brain barrier of rats with acute carbon monoxide poisoning].

PubMed

Wang, Li; Ding, Xiaoyu; Bi, Mingjun; Wang, Jinglin; Zou, Yong; Tang, Jiyou; Li, Qin

2018-05-01

To explore the effects of N-butylphthalide on the expressions of ZO-1 and claudin-5 in blood-brain barrier (BBB) in rats with acute carbon monoxide (CO) poisoning. A total of 144 adult healthy male Sprague-Dawley (SD) rats were randomly divided into normal control group, CO poisoning group, and NBP treatment group, with 48 rats in each group. The acute CO poisoning model was reproduced in hyperbaric oxygen chamber, and all model rats were given hyperbaric oxygen therapy once daily. The rats in the normal control group were free to breathe fresh air. The rats in NBP treatment group were administered orally NBP 60 mg/kg twice a day at 2 hours after poisoning until death. The rats in normal control group and CO poisoning group were treated with equal amount of pure olive oil. Four rats were sacrificed from each group at 1, 3, 7, 14 days after model reproducing, respectively. The changes in ultrastructure of BBB were observed under transmission electron microscope. The expressions of ZO-1 and claudin-5 proteins were determined by immunofluorescence staining and Western Blot. The localization of the two target proteins was observed by immunofluorescence double staining. The correlation between the two proteins was analyzed by linear regression. The ultrastructure of BBB was normal in normal control group, some ZO-1 and a large number of claudin-5 positive cells were observed. The ultrastructure of BBB was seriously injured, ZO-1 and claudin-5 positive cells in brain tissue were significantly decreased, and the expressions of ZO-1 and claudin-5 proteins in brain tissue at 1 day after poisoning in CO poisoning group were significantly lower than those of normal control group (ZO-1 protein: 3.38±0.30 vs. 24.50±5.62, claudin-5 protein: 11.38±0.93 vs. 46.35±6.88, both P < 0.05), and although gradually restored, they were maintained at relatively lower levels until 14 days as compared with those in normal control group (ZO-1 protein: 10.35±0.80 vs. 24.63±3.57, claudin-5 protein: 32.35±3.11 vs. 46.43±7.20, both P < 0.05). NBP treatment could significantly alleviate the ultrastructure injury of BBB induced by acute CO poisoning, the amount of ZO-1 and claudin-5 positive cells in brain tissue were significantly increased, as well as the expressions of ZO-1 and claudin-5 proteins were significantly increased, which were significantly higher than those of CO poisoning group from 1 day and 3 days on, respectively (1-day ZO-1 protein: 7.57±0.69 vs. 3.38±0.30, 3-day claudin-5 protein: 20.46±1.42 vs. 11.43±0.86, both P < 0.05), and which showed an increase tendency with time prolongation. The results of immunofluorescence double staining showed that ZO-1 and claudin-5 proteins could not only coexist in the same cell, but also could be expressed separately in different cells. Linear regression analysis showed the positive correlation between the expressions of ZO-1 and claudin-5 proteins in brain tissue of rats with acute CO poisoning (R 2 = 0.917, P = 0.022). NBP could markedly improve the ultrastructure and functional integrity of BBB through up-regulating the expressions of ZO-1 and claudin-5 proteins, and then reduce brain damage caused by CO poisoning.

Ultrastructural Effects of Bacillus thuringiensis var. san diego on Midgut Cells of the Cottonwood Leaf Beetle1

Treesearch

Leah S. Bauer; Stuart H. Pankratz

1992-01-01

Sequential observations of the ultrastructural effects of Bacillus thuringiensis var. san diego were made on midgut epithelial cells of the cottonwood leaf beetle, Chrysomela scripta F. Larvae imbibed a droplet of B. thuringiensis var. san diego containing endotoxin and live...

HEPATOBLASTOMAS IN THE MUMMICHOG, FUNDULUS HETEROCLITUS (L.), FROM A CREOSOTE-CONTAMINATED ENVIRONMENT: A HISTOLOGIC, ULTRASTRUCTURAL AND IMMUNOHISTOCHEMICAL STUDY

EPA Science Inventory

A detailed histologic and ultrastructural description of two cases of hepatoblastoma, a primitive liver cell neoplasm, is provided from mummichog, Fundulus heteroclitus(L.), inhabiting a creosote-contaminated site in the Elizabeth River, Virginia, USA. Both neoplasms were multifo...

Mitochondria-targeted antioxidant SkQ1 reduces age-related alterations in the ultrastructure of the lacrimal gland

PubMed Central

Bakeeva, Lora E.; Eldarov, Chupalav M.; Vangely, Irina M.; Kolosova, Nataliya G.; Vays, Valeriya B.

2016-01-01

Dry eye syndrome is an eye disorder affecting many people at an old age. Because dry eye syndrome is accelerated by aging, a useful approach to the prevention of this syndrome may be an intervention into the aging process. Previously, we showed that the mitochondria-targeted antioxidant SkQ1 delays manifestations of aging and inhibits the development of age-related diseases including dry eye syndrome. Nevertheless, the link between SkQ1's effects and its suppression of age-related changes in the lacrimal gland remains unclear. Here we demonstrated that dietary supplementation with SkQ1 (250 nmol/[kg body weight] daily) starting at age 1.5 months significantly alleviated the pathological changes in lacrimal glands of Wistar rats by age 24 months. By this age, lacrimal glands underwent dramatic deterioration of the ultrastructure that was indicative of irreversible disturbances in these glands' functioning. In contrast, in SkQ1-treated rats, the ultrastructure of the lacrimal gland was similar to that in much younger rats. Morphometric analysis of electron-microscopic specimens of lacrimal glands revealed the presence of numerous secretory granules in acinar cells and a significant increase in the number of operating intercalary ducts. Our results confirm that dietary supplementation with SkQ1 is a promising approach to healthy ageing and to prevention of aberrations in the lacrimal gland that underlie dry eye syndrome. PMID:27852065

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

PubMed

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.

Sub-Lethal Dose of Shiga Toxin 2 from Enterohemorrhagic Escherichia coli Affects Balance and Cerebellar Cytoarchitecture

PubMed Central

Pinto, Alipio; Cangelosi, Adriana; Geoghegan, Patricia A.; Tironi-Farinati, Carla; Brener, Gabriela J.; Goldstein, Jorge

2016-01-01

Shiga toxin producing Escherichia coli may damage the central nervous system before or concomitantly to manifested hemolytic–uremic syndrome symptoms. The cerebellum is frequently damaged during this syndrome, however, the deleterious effects of Shiga toxin 2 has never been integrally reported by ultrastructural, physiological and behavioral means. The aim of this study was to determine the cerebellar compromise after intravenous administration of a sub-lethal dose of Shiga toxin 2 by measuring the cerebellar blood–brain barrier permeability, behavioral task of cerebellar functionality (inclined plane test), and ultrastructural analysis (transmission electron microscope). Intravenous administration of vehicle (control group), sub-lethal dose of 0.5 and 1 ηg of Stx2 per mouse were tested for behavioral and ultrastructural studies. A set of three independent experiments were performed for each study (n = 6). Blood–brain barrier resulted damaged and consequently its permeability was significantly increased. Lower scores obtained in the inclined plane task denoted poor cerebellar functionality in comparison to their controls. The most significant lower score was obtained after 5 days of 1 ηg of toxin administration. Transmission electron microscope micrographs from the Stx2-treated groups showed neurons with a progressive neurodegenerative condition in a dose dependent manner. As sub-lethal intravenous Shiga toxin 2 altered the blood brain barrier permeability in the cerebellum the toxin penetrated the cerebellar parenchyma and produced cell damaged with significant functional implications in the test balance. PMID:26904009

GEITLERINEMA SPECIES (OSCILLATORIALES, CYANOBACTERIA) REVEALED BY CELLULAR MORPHOLOGY, ULTRASTRUCTURE, AND DNA SEQUENCING(1).

PubMed

Do Carmo Bittencourt-Oliveira, Maria; Do Nascimento Moura, Ariadne; De Oliveira, Mariana Cabral; Sidnei Massola, Nelson

2009-06-01

Geitlerinema amphibium (C. Agardh ex Gomont) Anagn. and G. unigranulatum (Rama N. Singh) Komárek et M. T. P. Azevedo are morphologically close species with characteristics frequently overlapping. Ten strains of Geitlerinema (six of G. amphibium and four of G. unigranulatum) were analyzed by DNA sequencing and transmission electronic and optical microscopy. Among the investigated strains, the two species were not separated with respect to cellular dimensions, and cellular width was the most varying characteristic. The number and localization of granules, as well as other ultrastructural characteristics, did not provide a means to discriminate between the two species. The two species were not separated either by geography or environment. These results were further corroborated by the analysis of the cpcB-cpcA intergenic spacer (PC-IGS) sequences. Given the fact that morphology is very uniform, plus the coexistence of these populations in the same habitat, it would be nearly impossible to distinguish between them in nature. On the other hand, two of the analyzed strains were distinct from all others based on the PC-IGS sequences, in spite of their morphological similarity. PC-IGS sequences indicate that these two strains could be a different species of Geitlerinema. Using morphology, cell ultrastructure, and PC-IGS sequences, it is not possible to distinguish G. amphibium and G. unigranulatum. Therefore, they should be treated as one species, G. unigranulatum as a synonym of G. amphibium. © 2009 Phycological Society of America.

Ultra-structural hair alterations of drug abusers: a scanning electron microscopic investigation

PubMed Central

Turkmenoglu, Fatma Pinar; Kasirga, Ugur Baran; Celik, Hakan Hamdi

2015-01-01

As drug abuse carries a societal stigma, patients do not often report their history of drug abuse to the healthcare providers. However, drug abuse is highly co-morbid with a host of other health problems such as psychiatric disorders and skin diseases, and majority of individuals with drug use disorders seek treatment in the first place for other problems. Therefore, it is very important for physicians to be aware of clinical signs and symptoms of drug use. Recently diagnostic value of dermatologic tissue alterations associated with drug abuse has become a very particular interest because skin changes were reported to be the earliest noticeable consequence of drug abuse prompting earlier intervention and treatment. Although hair is an annex of skin, alterations on hair structure due to drug use have not been demonstrated. This study represents the first report on ultra-structural hair alterations of drug abusers. We have investigated ultra-structure of the hair samples obtained from 6 cocaine, 6 heroin, 7 cannabis and 4 lysergic acid diethylamide (LSD) abusers by scanning electron microscope (SEM). SEM analysis of hair samples gave us drug-specific discriminating alterations. We suggest that results of this study will make a noteworthy contribution to cutaneous alterations associated with drug abuse which are regarded as the earliest clinical manifestations, and this SEM approach is a very specific and effective tool in the detection of abuse of respective drugs, leading early treatment. PMID:26309532

Probabilistic failure analysis of bone using a finite element model of mineral-collagen composites.

PubMed

Dong, X Neil; Guda, Teja; Millwater, Harry R; Wang, Xiaodu

2009-02-09

Microdamage accumulation is a major pathway for energy dissipation during the post-yield deformation of bone. In this study, a two-dimensional probabilistic finite element model of a mineral-collagen composite was developed to investigate the influence of the tissue and ultrastructural properties of bone on the evolution of microdamage from an initial defect in tension. The probabilistic failure analyses indicated that the microdamage progression would be along the plane of the initial defect when the debonding at mineral-collagen interfaces was either absent or limited in the vicinity of the defect. In this case, the formation of a linear microcrack would be facilitated. However, the microdamage progression would be scattered away from the initial defect plane if interfacial debonding takes place at a large scale. This would suggest the possible formation of diffuse damage. In addition to interfacial debonding, the sensitivity analyses indicated that the microdamage progression was also dependent on the other material and ultrastructural properties of bone. The intensity of stress concentration accompanied with microdamage progression was more sensitive to the elastic modulus of the mineral phase and the nonlinearity of the collagen phase, whereas the scattering of failure location was largely dependent on the mineral to collagen ratio and the nonlinearity of the collagen phase. The findings of this study may help understanding the post-yield behavior of bone at the ultrastructural level and shed light on the underlying mechanism of bone fractures.

Probabilistic Failure Analysis of Bone Using a Finite Element Model of Mineral-Collagen Composites

PubMed Central

Dong, X. Neil; Guda, Teja; Millwater, Harry R.; Wang, Xiaodu

2009-01-01

Microdamage accumulation is a major pathway for energy dissipation during the post-yield deformation of bone. In this study, a two-dimensional probabilistic finite element model of a mineral-collagen composite was developed to investigate the influence of the tissue and ultrastructural properties of bone on the evolution of microdamage from an initial defect in tension. The probabilistic failure analyses indicated that the microdamage progression would be along the plane of the initial defect when the debonding at mineral-collagen interfaces was either absent or limited in the vicinity of the defect. In this case, the formation of a linear microcrack would be facilitated. However, the microdamage progression would be scattered away from the initial defect plane if interfacial debonding takes place at a large scale. This would suggest the possible formation of diffuse damage. In addition to interfacial debonding, the sensitivity analyses indicated that the microdamage progression was also dependent on the other material and ultrastructural properties of bone. The intensity of stress concentration accompanied with microdamage progression was more sensitive to the elastic modulus of the mineral phase and the nonlinearity of the collagen phase, whereas the scattering of failure location was largely dependent on the mineral to collagen ratio and the nonlinearity of the collagen phase. The findings of this study may help understanding the post-yield behavior of bone at the ultrastructural level and shed light on the underlying mechanism of bone fractures. PMID:19058806

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

PubMed

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.

Comparative effects of glyphosate and atrazine in chloroplast ultrastructure of wheat and downy brome. [Triticum aestivum; Bromus tectorum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Auge, R.M.; Gealy, D.R.; Ogg, A.G.

1987-04-01

Developing and mature leaves of winter wheat (Triticum aestivum L. var. Daws) and the weed species downy brome (Bromus tectorum L.) were subjected to 10 mM (foliar application) and 1 mM (root application) herbicide solutions. Glyphosate (N-(phosphonomethyl) glycine) and atrazine (2-chloro-4-(ethyl-amino)-6-(isopropylamino)-s-triazine) were prepared in a carrier composed of 5% soybean oil concentrate, 35% acetone and 60% water. Penetration experiments with /sup 3/H-labelled herbicides assessed what percentage of herbicide entered leaves, and microautoradiography was used to determine qualitatively how much herbicide was present in the sections viewed with TEM. Tissue was excised at 4, 18, 62 and 200 hours, and thenmore » either freeze-substituted or fixed chemically. Ultrastructural effects of each herbicide on chloroplasts from leaves of newly-germinated seedlings and of well-tillered plants are depicted and discussed. Temporal differences in response of chloroplasts to each herbicide are noted.« less

The morphology and ultrastructure of salivary glands of Zoraptera (Insecta).

PubMed

Dallai, R; Mercati, D; Mashimo, Y; Machida, R; Beutel, R G

2017-07-01

The salivary glands of two species of Zoraptera, Zorotypus caudelli and Zorotypus hubbardi, were examined and documented mainly using transmission electron microscopy (TEM). The results obtained for males and females of the two species are compared and functional aspects related to ultrastructural features are discussed. The salivary glands are divided into two regions: the secretory cell region and the long efferent duct, the latter with its distal end opening in the salivarium below the hypopharyngeal base. The secretory region consists of a complex of secretory cells provided with microvillated cavities connected by short ectodermal ducts to large ones, which are connected with the long efferent duct. The secretory cell cytoplasm contains a large system of rough endoplasmic reticulum and Golgi apparatus producing numerous dense secretions. The cells of the efferent duct, characterized by reduced cytoplasm and the presence of long membrane infoldings associated with mitochondria, are possibly involved in fluid uptaking from the duct lumen. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ultrastructural instability of paired helical filaments from corticobasal degeneration as examined by scanning transmission electron microscopy.

PubMed Central

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 CBD and AD differ both in stability and packing of tau and that CBD filaments, composed of two distinct protofilaments, are more labile under STEM conditions. As fixed and stained filaments from CBD have been shown to be stable and uniform in size by conventional transmission electron microscopy, STEM studies may be particularly suitable for detecting instability of unstained and unfixed filaments. The results also suggest that molecular heterogeneity and/or post-translational modifications of tau may strongly influence the morphology and stability of abnormal filaments. Images Figure 1 Figure 2 Figure 3 PMID:8702002

Squid ink polysaccharide prevents autophagy and oxidative stress affected by cyclophosphamide in Leydig cells of mice: a pilot study

PubMed Central

Gu, Yi-Peng; Yang, Xiao-Mei; Duan, Zhen-Hua; Shang, Jiang-Hua; Luo, Ping; Xiao, Wei; Zhang, Da-Yan; Liu, Hua-Zhong

2017-01-01

Objective(s): The aim of this study was to explore the effects of Squid ink polysaccharide (SIP) on prevention of autophagy and oxidative stress induced by cyclophosphamide (CP) in Leydig cells of mice. Materials and Methods: Examination of reproductive organ exponents, abnormal sperm rate, activities of superoxide dismutase (SOD), catalase (CAT), contents of malondialdehyde (MDA), and histological structure were performed to detect the optimal dose of SIP against oxidative stress damage in vivo, and autophagy-associated protein LC3 and Beclin-1 were examined by immunofluorescence, and their expression was detected by Western blot analysis. Leydig cells ultrastructural changes were observed by transmission fluorescent microscope. Results: SIP significantly inhibited sperm aberration, histological structure and injury of seminiferous tubules caused by CP, as well as the antioxidant activity of SOD and CAT were increased; contents of MDA were decreased. The optimal dose of SIP for prevention of oxidative stress injury by CP was 80 mg/kg. In addition, LC3 and Beclin-1 fluorescent granules were much less in the Leydig cell layer after treatment via SIP compared with the CP-treated group, and the expression levels of LC3 and Beclin-1 were also decreased. Furthermore, characteristics of cell autophagy such as mitochondrial swelling, autophagic vacuoles, and chromatin pyknosis were observed in CP-treated Leydig cells, but SIP could effectively weaken injury of Leydig cell ultrastructure by CP. Conclusion: SIP, as an antioxidant, prevents the cytoskeleton damage through up-regulation antioxidant capacity and inhibition autophagy caused by CP. PMID:29299195

ISOCT study of collagen crosslinking of collagen in cancer models (Conference Presentation)

NASA Astrophysics Data System (ADS)

Spicer, Graham; Young, Scott T.; Yi, Ji; Shea, Lonnie D.; Backman, Vadim

2016-03-01

The role of extracellular matrix modification and signaling in cancer progression is an increasingly recognized avenue for the progression of the disease. Previous study of field effect carcinogenesis with Inverse Spectroscopic Optical Coherence Tomography (ISOCT) has revealed pronounced changes in the nanoscale-sensitive mass fractal dimension D measured from field effect tissue when compared to healthy tissue. However, the origin of this difference in tissue ultrastructure in field effect carcinogenesis has remained poorly understood. Here, we present findings supporting the idea that enzymatic crosslinking of the extracellular matrix is an effect that presents at the earliest stages of carcinogenesis. We use a model of collagen gel with crosslinking induced by lysyl oxidase (LOXL4) to recapitulate the difference in D previously reported from healthy and cancerous tissue biopsies. Furthermore, STORM imaging of this collagen gel model verifies the morphologic effects of enzymatic crosslinking at length scales as small as 40 nm, close to the previously reported lower length scale sensitivity threshold of 35 nm for ISOCT. Analysis of the autocorrelation function from STORM images of collagen gels and subsequent fitting to the Whittle-Matérn correlation function shows a similar effect of LOXL4 on D from collagen measured with ISOCT and STORM. We extend this to mass spectrometric study of tissue to directly measure concentrations of collagen crosslink residues. The validation of ISOCT as a viable tool for non-invasive rapid quantification of collagen ultrastructure lends it to study other physiological phenomena involving ECM restructuring such as atherosclerotic plaque screening or cervical ripening during pregnancy.

Morphological, ultrastructural, and molecular characterization of intestinal tetratrichomonads isolated from non-human primates in southeastern Brazil.

PubMed

Dos Santos, Caroline Spitz; de Jesus, Vera Lúcia Teixeira; McIntosh, Douglas; Carreiro, Caroline Cunha; Batista, Lilian Cristina Oliveira; do Bomfim Lopes, Bruno; Neves, Daniel Marchesi; Lopes, Carlos Wilson Gomes

2017-09-01

Non-human primates are our closest relatives and represent an interesting model for comparative parasitological studies. However, research on this topic particularly in relation to intestinal parasites has been fragmentary and limited mainly to animals held in captivity. Thus, our knowledge of host-parasite relationships in this species-rich group of mammals could be considered rudimentary. The current study combined morphological, ultrastructural, and molecular analyses to characterize isolates of intestinal tetratrichomonads recovered from the feces of three species of South American, non-human primates. Fecal samples were collected from 16 animals, representing 12 distinct species. Parabasalid-like organisms were evident in five samples (31%) of feces: two from Alouatta sara, two from Callithrix penicillata, and one from Sapajus apella. The five samples presented morphologies consistent with the description of Tetratrichomonas sp., with four anterior flagella of unequal length, a well-developed undulating membrane, and a long recurrent flagellum. Sequencing of the ITS1-5.8S rRNA-ITS2 region demonstrated that the isolates from A. sara, and C. penicillata were closely related and highly similar to isolates of Tetratrichomonas brumpti, recovered previously from tortoises (Geochelone sp.). The flagellate recovered from S. apella demonstrated a similar morphology to those of the other isolates, however, sequence analysis showed it to be identical to an isolate of Tetratrichomonas sp. recovered from white-lipped peccaries (Tayassu pecari). The findings of this study extend and enhance our knowledge of parasitism of non-human primates by members of the genus Tetratrichomonas and indicate that the host range of these parasites is broader than previously believed.

Changes of cervical dorsal root ganglia induced by compression injury and decompression procedure: a novel rat model of cervical radiculoneuropathy.

PubMed

Tang, Zhan-Ying; Shu, Bing; Cui, Xue-Jun; Zhou, Chong-Jian; Shi, Qi; Holz, Jonathan; Wang, Yong-Jun

2009-02-11

Our study aimed to establish a model of compression injury of cervical dorsal root ganglia (DRG) in the rat and to investigate the pathological changes following compression injury and decompression procedures. Thirty rats were divided into three groups: control group receiving sham surgery, compression group undergoing surgery to place a micro-silica gel on C6 DRG, and decompression group with subsequent decompression procedure. The samples harvested from the different groups were examined with light microscopy, ultrastructural analysis, and horseradish peroxidase (HRP) retrograde tracing techniques. Apoptosis of DRG neurons was demonstrated with TUNEL staining. Changes in PGE2 and PLA2 in DRG neurons were detected with enzyme-linked immunosorbent assay (ELISA). Local expression of vascular endothelial growth factor (VEGF) was monitored with immunohistochemistry. DRG neurons in the compression group became swollen with vacuolar changes in cytoplasm. Decompression procedure partially ameliorated the resultant compression pathology. Ultrastructural examination showed a large number of swollen vacuoles, demyelinated nerve root fibers, absence of Schwann cells, and proliferation in the surrounding connective tissues in the compression group. Compared to the control group, the compression group showed a significant decrease in the number of the HRP-labeled cells and a significant increase in levels of PGE2 and PLA2, in the expression of VEGF protein, and in the number of apoptotic DRG neurons. These findings demonstrate that compression results in local inflammation, followed by increased apoptosis and upregulation of VEGF. We conclude that such a model provides a tool to study the pathogenesis and treatment of cervical radiculoneuropathy.

Oocytes with a dark zona pellucida demonstrate lower fertilization, implantation and clinical pregnancy rates in IVF/ICSI cycles.

PubMed

Shi, Wei; Xu, Bo; Wu, Li-Min; Jin, Ren-Tao; Luan, Hong-Bing; Luo, Li-Hua; Zhu, Qing; Johansson, Lars; Liu, Yu-Sheng; Tong, Xian-Hong

2014-01-01

The morphological assessment of oocytes is important for embryologists to identify and select MII oocytes in IVF/ICSI cycles. Dysmorphism of oocytes decreases viability and the developmental potential of oocytes as well as the clinical pregnancy rate. Several reports have suggested that oocytes with a dark zona pellucida (DZP) correlate with the outcome of IVF treatment. However, the effect of DZP on oocyte quality, fertilization, implantation, and pregnancy outcome were not investigated in detail. In this study, a retrospective analysis was performed in 268 infertile patients with fallopian tube obstruction and/or male factor infertility. In 204 of these patients, all oocytes were surrounded by a normal zona pellucida (NZP, control group), whereas 46 patients were found to have part of their retrieved oocytes enclosed by NZP and the other by DZP (Group A). In addition, all oocytes enclosed by DZP were retrieved from 18 patients (Group B). No differences were detected between the control and group A. Compared to the control group, the rates of fertilization, good quality embryos, implantation and clinical pregnancy were significantly decreased in group B. Furthermore, mitochondria in oocytes with a DZP in both of the two study groups (A and B) were severely damaged with several ultrastructural alterations, which were associated with an increased density of the zona pellucida and vacuolization. Briefly, oocytes with a DZP affected the clinical outcome in IVF/ICSI cycles and appeared to contain more ultrastructural alterations. Thus, DZP could be used as a potential selective marker for embryologists during daily laboratory work.

Long-Term Spinal Ventral Root Reimplantation, but not Bone Marrow Mononuclear Cell Treatment, Positively Influences Ultrastructural Synapse Recovery and Motor Axonal Regrowth

PubMed Central

Barbizan, Roberta; Castro, Mateus V.; Ferreira Jr., Rui Seabra; Barraviera, Benedito; Oliveira, Alexandre L. R.

2014-01-01

We recently proposed a new surgical approach to treat ventral root avulsion, resulting in motoneuron protection. The present work combined such a surgical approach with bone marrow mononuclear cells (MC) therapy. Therefore, MC were added to the site of reimplantation. Female Lewis rats (seven weeks old) were subjected to unilateral ventral root avulsion (VRA) at L4, L5 and L6 levels and divided into the following groups (n = 5 for each group): Avulsion, sealant reimplanted roots and sealant reimplanted roots plus MC. After four weeks and 12 weeks post-surgery, the lumbar intumescences were processed by transmission electron microscopy, to analyze synaptic inputs to the repaired α motoneurons. Also, the ipsi and contralateral sciatic nerves were processed for axon counting and morphometry. The ultrastructural results indicated a significant preservation of inhibitory pre-synaptic boutons in the groups repaired with sealant alone and associated with MC therapy. Moreover, the average number of axons was higher in treated groups when compared to avulsion only. Complementary to the fiber counting, the morphometric analysis of axonal diameter and “g” ratio demonstrated that root reimplantation improved the motor component recovery. In conclusion, the data herein demonstrate that root reimplantation at the lesion site may be considered a therapeutic approach, following proximal lesions in the interface of central nervous system (CNS) and peripheral nervous system (PNS), and that MC therapy does not further improve the regenerative recovery, up to 12 weeks post lesion. PMID:25353176

Microscopic and ultrastructural changes of Müller's muscle in patients with simple congenital ptosis.

PubMed

Alshehri, Mohammed D; Al-Fakey, Yasser H; Alkhalidi, Hisham M; Mubark, Mohamed A; Alsuhaibani, Adel H

2014-01-01

To study microscopic and ultrastructural changes of Müller's muscle in patients with isolated congenital ptosis. In this prospective, observational case-control study, Müller's muscle specimens were collected during ptosis surgical correction for 18 consecutive patients. Each specimen was divided into 2 parts. One part was embedded in formalin for light microscopy, and the other one was fixed in 3% glutaraldehyde for electron microscopy. A neuropathologist, serving as a masked evaluator, blindly reviewed all the different features for every case and counted the number of myocytes showing distinct myofilaments in the whole grid for every case. Statistical analysis using compare means and correlation tests was conducted to investigate potential associations and/or differences within and across groups. Twelve Müller's muscle specimens from patients with simple congenital ptosis of various severities and 6 specimens from patients with aponeurotic ptosis (controls) were collected and studied. Under light microscopy, congenital ptosis slides showed a small number of dispersed myocytes in a fibrotic background, whereas acquired ptosis slides showed a greater number of well-defined myocytes. Under electron microscopy, all congenital ptosis specimens had only a very small number of myocytes with clear, distinct myofilaments. Most myocytes in the aponeurotic ptosis group showed clear, distinct myofilaments, indicating a well-preserved muscle. No relationship existed between the number of clear, distinct myofilaments observed in the congenital ptosis group by transmission electron microscopy and patient age or ptosis severity. Substantial Müller's muscle atrophy was observed in patients with different severities of isolated congenital ptosis.

[The epithelial junctional zones of the anal canal and cervix uterus: the ultrastructure of tumors of these zones].

PubMed

Chernyĭ, A P; Iakovleva, N I

1990-01-01

Relationships between squamous and columnar epithelia in the anal canal and cervix uteri of postnatal period and fetus were studied. The transitional stratified epithelial lining, which is called junctional epithelium, is interposed between the mentioned epithelia. The junctional epithelium has variable numbers of layers of epidermoid cells, which differ from cells of atypical squamous epithelium by some ultrastructural features of the cytoskeleton and cell surface and by a low content of glycogen. The hypothesis on the physiological significance of this epithelium is proposed. Ultrastructural features of the cytoskeleton and cell surface suggest that anal basaloid carcinomas and some cervical squamous carcinomas may develop from so-called junctional epithelium.

[Ultrastructural changes of human dental hard tissues during orthodontic treatment with fixed appliances].

PubMed

Antonova, I N; Goncharov, V D; Bobrova, E A

The aim of the study was to evaluate ultrastructural changes of dental enamel after fixation of orthodontic appliances, initial influence of orthodontic forces and removal of braces. Five intact permanent tooth extracted for orthodontic reasons were included in the experimental study. Scanning probe microscopy was conducted in 4 random enamel points in each tooth (20 points overall) in semi-contact mode with standard 10 nm probes. The study showed ultrastructural enamel changes such as nanofractures up to 1 mm along the braces locks. The changes correlated with surface morphological features and teeth anatomy and may play an important role in dental decay and non-carious lesions occurring in the course of orthodontic treatment.

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

PubMed

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.

Gastric cryptosporidiosis in freshwater angelfish (Pterophyllum scalare)

USGS Publications Warehouse

Murphy, B.G.; Bradway, D.; Walsh, T.; Sanders, G.E.; Snekvik, K.

2009-01-01

A freshwater angelfish (Pterophyllum scalare) hatchery experienced variable levels of emaciation, poor growth rates, swollen coelomic cavities, anorexia, listlessness, and increased mortality within their fish. Multiple chemotherapeutic trials had been attempted without success. In affected fish, large numbers of protozoa were identified both histologically and ultrastructurally associated with the gastric mucosa. The youngest cohort of parasitized fish was the most severely affected and demonstrated the greatest morbidity and mortality. The protozoa were morphologically most consistent with Cryptosporidium. All of the protozoan life stages were identified ultrastructurally and protozoal genomic DNA was isolated from parasitized tissue viscera and sequenced. Histological, ultrastructural, genetic, and phylogenetic analyses confirmed this protozoal organism to be a novel species of Cryptosporidium.

Induced molt using cassava meal. 2. Effects on eggshell quality, ultrastructure, and pore density in late-phase laying hens.

PubMed

Gongruttananun, N

2018-03-01

This experiment was conducted to investigate the effect of a non-fasting induced molt using cassava meal on the eggshell quality, ultrastructure, and porosity in late-phase (74 wk old) H&N Brown laying hens. Hens were randomly assigned to 3 treatments of 90 birds each: 1) Controls with no induced molt (CONT); 2) molted by full feeding with cassava meal for 3 wk (FP3); and 3) molted by full feeding with cassava meal for 4 wk (FP4). Following the treatments, groups 2 and 3 were fed a pullet developer diet for 3 weeks. During the molt period, the birds were exposed to an 8L:16D photoperiod and had access to drinking water at all times. Thereafter, all hens were fed a layer diet (17% CP) and exposed to a 16L:8D photoperiod until the end of the study. Compared to the CONT treatment, significant reductions (P < 0.05) in shell weight, thickness, and breaking strength were identified on the sixth d of feeding the molt diet. Significant (P < 0.05) improvements in these parameters were observed for the FP3 and FP4 treatments during the post-molt period, with the greater degree in the FP4 treatment. In addition, scanning electron microscopy revealed a smaller size of mammillary knobs accompanied by a higher density of mammillae in eggs taken from the molted treatments. Evidence of type B mammillae was detected in an egg produced by the CONT hens, whereas confluent and cuffing mammillae were observed in an egg taken from the FP4 birds. Reduced pore densities were found in the molted treatments in some periods of the post-molt production as compared to the CONT treatment. It was concluded that feeding the cassava molt diet for 4 wk could be an effective non-fasting molt method for improving eggshell quality, ultrastructure, and porosity in post-molt laying hens.

Quantitative and ultrastructural changes in the haemocytes of Spodoptera littoralis (Boisd.) treated individually or in combination with Spodoptera littoralis multicapsid nucleopolyhedrovirus (SpliMNPV) and azadirachtin.

PubMed

Shaurub, El-Sayed H; Abd El-Meguid, Afaf; Abd El-Aziz, Nahla M

2014-10-01

The total haemocyte count (THC) and the possible ultrastructural alterations induced in the haemocytes of the fourth larval instars of the Egyptian cotton leafworm, Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae), 96 h post-feeding on a semi-synthetic diet, treated with the LC50 of Spodoptera littoralis multicapsid nucleopolyhedrovirus (SpliMNPV) and the LC50 of azadirachtin alone, and the LC25 of SpliMNPV combined with the LC25 of azadirachtin were studied and compared to the control. Single treatment with the virus and azadirachtin or combined treatment significantly decreased the THC compared to the control. There are five types of haemocytes in S. littoralis: prohaemocytes, plasmatocytes, granulocytes, spherulocytes and oenocytoids. The most common symptoms in granulocytes and plasmatocytes, the main affected cell types, due to viral infection were the presence of virogenic stroma, peripheral dispersion of the chromatin and disappearance of the nucleoli. However, the most common symptoms in these two types of haemocytes due to treatment with azadirachtin were the presence of rough endoplasmic reticulum filled with fibrous materials, due to probably apoptosis, in their cisternae and disorganization of mitochondria (looped, vacuolated and swollen). In addition, the cytoplasm of granulocytes was vacuolated with the appearance of autophagic lysosomes, while plasmatocytes showed ruptured cell membrane and folded nuclear envelope. Combined treatment with the NPV and azadirachtin induced the same pathological changes which were recorded from individual treatment with the virus or azadirachtin to the same haemocytes. It can be concluded that the change in the THC and ultrastructure of granulocytes and plasmatocytes may affect the cellular-mediated immune response in S. littoralis. Moreover, it seems likely that mitochondria were the target site of azadirachtin, as they were affected in both granulocytes and plasmatocytes treated with azadirachtin alone or in combination with SpliMNPV. Copyright © 2014 Elsevier Ltd. All rights reserved.

Pathomechanisms of Dopamine Dysregulation in DYT1 Dystonia: Targets for Therapeutics

DTIC Science & Technology

2016-10-01

DA release in DYT1(ΔE) knockin mice by assessing VMAT2 function, vesicle utilization, the ultrastructure of DA terminals, and D2 DA...in slice, the ultrastructure of DA terminals, D2 DA autoreceptor function nicotinic AChR (nAChR) heteroreceptors function. 2) To determine the

Hypertextual Ultrastructures: Movement and Containment in Texts and Hypertexts

ERIC Educational Resources Information Center

Coste, Rosemarie L.

2009-01-01

The surface-level experience of hypertextuality as formless and unbounded, blurring boundaries among texts and between readers and writers, is created by a deep structure which is not normally presented to readers and which, like the ultrastructure of living cells, defines and controls texts' nature and functions. Most readers, restricted to…

Ultrastructure of spermatozoa in cobia, Rachycentron canadum (Linnaeus, 1766).

PubMed

Dhanasekar, Krishnamoorthy; Selvakumar, Narasimman; Munuswamy, Natesan

2018-02-01

Ultrastructure and development of spermatozoa in cobia, Rachycentron canadum are described. Sections through the testis show different developmental stages viz, Spermatocytes, spermatids and sperm. Spermatozoa of R. canadum exhibit the configuration of uniflagellated, anacrosomal Type I aquasperm, typical for externally fertilizing fish. Mature spermatozoon is seen with a prominent head and long cylindrical flagellum. Ultrastructure of sperm shows invaginated 'U' shaped nucleus and other organelles. The mitochondrial matrix is electron-dense with irregular arrangement of the cristae. The nucleus reveals a deep invagination (nuclear fossa) in which the centriolar complex is located. The centriolar complex lies inside the nuclear fossa and is composed of a proximal and a distal centriole. The two centrioles are placed perpendicular to each other. The flagellum has a typical eukaryotic organization (microtubule doublets 9 + 2 pattern) and measures around 36.21 ± 0.42 μm in length. This study for the first time provides a comprehensive detail on the ultrastructure and developmental process of sperm in cobia, R. canadum. Copyright © 2017 Elsevier B.V. All rights reserved.

Studies of chain substitution caused sub-fibril level differences in stiffness and ultrastructure of wildtype and oim/oim collagen fibers using multifrequency-AFM and molecular modeling.

PubMed

Li, Tao; Chang, Shu-Wei; Rodriguez-Florez, Naiara; Buehler, Markus J; Shefelbine, Sandra; Dao, Ming; Zeng, Kaiyang

2016-11-01

Molecular alteration in type I collagen, i.e., substituting the α2 chain with α1 chain in tropocollagen molecule, can cause osteogenesis imperfecta (OI), a brittle bone disease, which can be represented by a mouse model (oim/oim). In this work, we use dual-frequency Atomic Force Microscopy (AFM) and incorporated with molecular modeling to quantify the ultrastructure and stiffness of the individual native collagen fibers from wildtype (+/+) and oim/oim diseased mice humeri. Our work presents direct experimental evidences that the +/+ fibers have highly organized and compact ultrastructure and corresponding ordered stiffness distribution. In contrast, oim/oim fibers have ordered but loosely packed ultrastructure with uncorrelated stiffness distribution, as well as local defects. The molecular model also demonstrates the structural and molecular packing differences between +/+ and oim/oim collagens. The molecular mutation significantly altered sub-fibril structure and mechanical property of collagen fibers. This study can give the new insight for the mechanisms and treatment of the brittle bone disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

Stage-two surgery using collagen soft tissue grafts: clinical cases and ultrastructural analysis.

PubMed

Fischer, Kai R; Fickl, Stefan; Mardas, Nikos; Bozec, Laurent; Donos, Nikolaos

2014-01-01

To present the application of two different soft tissue grafts around dental implants during stage-two surgery. Furthermore, the ultrastructure of these materials is shown and discussed using scanning electron microscopy (SEM). Although soft tissue autografts may be currently regarded as the gold standard, harvesting of these grafts might lead to higher morbidity, longer chair time, and intra-/postoperative complications at the donor site. New developments in collagen scaff olds have provided an alternative to successfully replace autologous grafts in clinical practice. The SEM pictures clearly show the different composition of a bilayer scaff old (collagen matrix, CM) and a porcine acellular dermal matrix (ADM). These distinctive properties lead to different possible indications. Within the presented cases, ADM was used to augment the ridge contour and was placed into a buccal pouch to achieve complete coverage and an uneventful closed healing. On the other side, CM was left exposed to the oral cavity to successfully gain keratinized mucosa around and between two dental implants.

Intracerebral Injections and Ultrastructural Analysis of High-Pressure Frozen Brain Tissue.

PubMed

Weil, Marie-Theres; Ruhwedel, Torben; Möbius, Wiebke; Simons, Mikael

2017-01-03

Intracerebral injections are an invasive method to bypass the blood brain barrier and are widely used to study molecular and cellular mechanisms of the central nervous system. The administered substances are injected directly at the site of interest, executing their effect locally. By combining injections in the rat brain with state-of-the-art electron microscopy, subtle changes in ultrastructure of the nervous tissue can be detected prior to overt damage or disease. The protocol presented here involves stereotactic injection into the corpus callosum of Lewis rats and the cryopreparation of freshly dissected tissue for electron microscopy. The localization of the injection site in tissue sections during the sample preparation for transmission electron microscopy is explained and possible artifacts of the method are indicated. With the help of this powerful combination of injections and electron microscopy, subtle effects of the applied substances on the biology of neural cells can be identified and monitored over time. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

Modeling pattern in collections of parameters

USGS Publications Warehouse

Link, W.A.

1999-01-01

Wildlife management is increasingly guided by analyses of large and complex datasets. The description of such datasets often requires a large number of parameters, among which certain patterns might be discernible. For example, one may consider a long-term study producing estimates of annual survival rates; of interest is the question whether these rates have declined through time. Several statistical methods exist for examining pattern in collections of parameters. Here, I argue for the superiority of 'random effects models' in which parameters are regarded as random variables, with distributions governed by 'hyperparameters' describing the patterns of interest. Unfortunately, implementation of random effects models is sometimes difficult. Ultrastructural models, in which the postulated pattern is built into the parameter structure of the original data analysis, are approximations to random effects models. However, this approximation is not completely satisfactory: failure to account for natural variation among parameters can lead to overstatement of the evidence for pattern among parameters. I describe quasi-likelihood methods that can be used to improve the approximation of random effects models by ultrastructural models.

[Ultrastructural analysis of the effect of antimicrobial drugs on the development of Chlamydia trachomatis in cells cultured in vitro].

PubMed

Falcieri, E; Cevenini, R; Landini, M P; Donati, M

1980-01-31

The Authors report the results of an ultrastructural study of the developmental cycle of Chlamydia trachomatis in cell cultures in vitro in the presence of inhibitors of te synthesis of DNA (mitomycin-C), RNA (actinomycin-D and rifampin) and proteins (oxytetracycline and chloramphenicol). The chlamidiae were grown to IUDR-pre-treated McCoy cell cultures and the drugs were added to the medium either immediately after the infection (in the presence of "elementary bodies" only) or after the appearance of the first "initial bodies" (14 hours after infection). The appearance of "initial bodies" or their multiplication was completely prevented in the infected cell cultures in the presence of mitomycin-C, actinomycin-D, rifampin and oxytetracycline added immediately after the infection or 14 hours after the infection, respectively. In the presence of chloramphenicol the appearance of "initial bodies" or their multiplication was possible, but their differentiation into "elementary bodies" was completely inhibited.

Fenitrothion induced oxidative stress and morphological alterations of sperm and testes in male sprague-dawley rats

PubMed Central

Taib, Izatus Shima; Budin, Siti Balkis; Ghazali, Ahmad Rohi; Jayusman, Putri Ayu; Louis, Santhana Raj; Mohamed, Jamaludin

2013-01-01

OBJECTIVE: Fenitrothion residue is found primarily in soil, water and food products and can lead to a variety of toxic effects on the immune, hepatobiliary and hematological systems. However, the effects of fenitrothion on the male reproductive system remain unclear. This study aimed to evaluate the effects of fenitrothion on the sperm and testes of male Sprague-Dawley rats. METHODS: A 20 mg/kg dose of fenitrothion was administered orally by gavages for 28 consecutive days. Blood sample was obtained by cardiac puncture and dissection of the testes and cauda epididymis was performed to obtain sperm. The effects of fenitrothion on the body and organ weight, biochemical and oxidative stress, sperm characteristics, histology and ultrastructural changes in the testes were evaluated. RESULTS: Fenitrothion significantly decreased the body weight gain and weight of the epididymis compared with the control group. Fenitrothion also decreased plasma cholinesterase activity compared with the control group. Fenitrothion altered the sperm characteristics, such as sperm concentration, sperm viability and normal sperm morphology, compared with the control group. Oxidative stress markers, such as malondialdehyde, protein carbonyl, total glutathione and glutathione S-transferase, were significantly increased and superoxide dismutase activity was significantly decreased in the fenitrothion-treated group compared with the control group. The histopathological and ultrastructural examination of the testes of the fenitrothion-treated group revealed alterations corresponding with the biochemical changes compared with the control group. CONCLUSION: A 20 mg/kg dose of fenitrothion caused deleterious effects on the sperm and testes of Sprague-Dawley rats. PMID:23420164

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

PubMed

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.

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

PubMed

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.

Photosynthetic Characteristics and Chloroplast Ultrastructure of Summer Maize Response to Different Nitrogen Supplies

PubMed Central

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 (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. Therefore, N2 treatment, 185 kg N ha-1, is the appropriate application rate for grain yield, photosynthesis and chloroplast ultrastructure. PMID:29765387

Photosynthetic Characteristics and Chloroplast Ultrastructure of Summer Maize Response to Different Nitrogen Supplies.

PubMed

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 shown in N3. Therefore, N2 treatment, 185 kg N ha -1 , is the appropriate application rate for grain yield, photosynthesis and chloroplast ultrastructure.

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

PubMed

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 researchers interested in pathology and electron microscopy. © Copyright Società Italiana di Anatomia Patologica e Citopatologia Diagnostica, Divisione Italiana della International Academy of Pathology.

Comparison between effects of pressure support and pressure-controlled ventilation on lung and diaphragmatic damage in experimental emphysema.

PubMed

Padilha, Gisele de A; Horta, Lucas F B; Moraes, Lillian; Braga, Cassia L; Oliveira, Milena V; Santos, Cíntia L; Ramos, Isalira P; Morales, Marcelo M; Capelozzi, Vera Luiza; Goldenberg, Regina C S; de Abreu, Marcelo Gama; Pelosi, Paolo; Silva, Pedro L; Rocco, Patricia R M

2016-12-01

In patients with emphysema, invasive mechanical ventilation settings should be adjusted to minimize hyperinflation while reducing respiratory effort and providing adequate gas exchange. We evaluated the impact of pressure-controlled ventilation (PCV) and pressure support ventilation (PSV) on pulmonary and diaphragmatic damage, as well as cardiac function, in experimental emphysema. Emphysema was induced by intratracheal instillation of porcine pancreatic elastase in Wistar rats, once weekly for 4 weeks. Control animals received saline under the same protocol. Eight weeks after first instillation, control and emphysema rats were randomly assigned to PCV (n = 6/each) or PSV (n = 6/each) under protective tidal volume (6 ml/kg) for 4 h. Non-ventilated control and emphysema animals (n = 6/group) were used to characterize the model and for molecular biology analysis. Cardiorespiratory function, lung histology, diaphragm ultrastructure alterations, extracellular matrix organization, diaphragmatic proteolysis, and biological markers associated with pulmonary inflammation, alveolar stretch, and epithelial and endothelial cell damage were assessed. Emphysema animals exhibited cardiorespiratory changes that resemble human emphysema, such as increased areas of lung hyperinflation, pulmonary amphiregulin expression, and diaphragmatic injury. In emphysema animals, PSV compared to PCV yielded: no changes in gas exchange; decreased mean transpulmonary pressure (Pmean,L), ratio between inspiratory and total time (Ti/Ttot), lung hyperinflation, and amphiregulin expression in lung; increased ratio of pulmonary artery acceleration time to pulmonary artery ejection time, suggesting reduced right ventricular afterload; and increased ultrastructural damage to the diaphragm. Amphiregulin correlated with Pmean,L (r = 0.99, p < 0.0001) and hyperinflation (r = 0.70, p = 0.043), whereas Ti/Ttot correlated with hyperinflation (r = 0.81, p = 0.002) and Pmean,L (r = 0.60, p = 0.04). In the model of elastase-induced emphysema used herein, PSV reduced lung damage and improved cardiac function when compared to PCV, but worsened diaphragmatic injury.

A novel fibrin-based artificial ovary prototype resembling human ovarian tissue in terms of architecture and rigidity.

PubMed

Chiti, Maria Costanza; Dolmans, Marie-Madeleine; Mortiaux, Lucie; Zhuge, Flanco; Ouni, Emna; Shahri, Parinaz Asiabi Kohneh; Van Ruymbeke, Evelyne; Champagne, Sophie-Demoustier; Donnez, Jacques; Amorim, Christiani Andrade

2018-01-01

The aim of this study is to optimize fibrin matrix composition in order to mimic human ovarian tissue architecture for human ovarian follicle encapsulation and grafting. Ultrastructure of fresh human ovarian cortex in age-related women (n = 3) and different fibrin formulations (F12.5/T1, F30/T50, F50/T50, F75/T75), rheology of fibrin matrices and histology of isolated and encapsulated human ovarian follicles in these matrices. Fresh human ovarian cortex showed a highly fibrous and structurally inhomogeneous architecture in three age-related patients, but the mean ± SD of fiber thickness (61.3 to 72.4 nm) was comparable between patients. When the fiber thickness of four different fibrin formulations was compared with human ovarian cortex, F50/T50 and F75/T75 showed similar fiber diameters to native tissue, while F12.5/T1 was significantly different (p value < 0.01). In addition, increased concentrations of fibrin exhibited enhanced storage modulus with F50/T50, resembling physiological ovarian rigidity. Excluding F12.5/T1 from further analysis, only three remaining fibrin matrices (F30/T50, F50/T50, F75/T75) were histologically investigated. For this, frozen-thawed fragments of human ovarian tissue collected from 22 patients were used to isolate ovarian follicles and encapsulate them in the three fibrin formulations. All three yielded similar follicle recovery and loss rates soon after encapsulation. Therefore, based on fiber thickness, porosity, and rigidity, we selected F50/T50 as the fibrin formulation that best mimics native tissue. Of all the different fibrin matrix concentrations tested, F50/T50 emerged as the combination of choice in terms of ultrastructure and rigidity, most closely resembling human ovarian cortex.

Midbody Accumulation in Breast Cancer Stem Cells

DTIC Science & Technology

2011-08-01

transit amplifying or differentiating cells. These results suggest that MBds are in almost exclusively in stem cells and putative breast cancer stem...confer tumor-like properties to these cells. We were unable to establish GFP-MKLP1 breast cancer cell lines for this analysis for some reason that we...and nonpolarized cells (Fig. 1c, d). Immuno- electron microscopy confirmed this localization and revealed ultrastructural features characteristic of

Giardia canis: ultrastructural analysis of G. canis trophozoites transfected with full length G. canis virus cDNA transcripts

USDA-ARS?s Scientific Manuscript database

Giardia canis virus (GCV) is a double-stranded RNA (dsRNA) virus of the family Totiviridae. In this study, the full-length cDNA of the G. canis virus was constructed in pPoly2/sfinot vector and RNA was transcribed in vitro. Virus-free G. canis trophozoites were transfected with in vitro transcribed ...

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

PubMed

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 hemoparasitic disease in this species.

New insights into valve-related intramural and intracellular bacterial diversity in infective endocarditis

PubMed Central

Feder, Stefan; Lehmann, Stefanie; Kullnick, Yvonne; Buschmann, Tilo; Blumert, Conny; Horn, Friedemann; Neuhaus, Jochen; Neujahr, Ralph; Bagaev, Erik; Hagl, Christian; Pichlmaier, Maximilian; Rodloff, Arne Christian; Gräber, Sandra; Kirsch, Katharina; Sandri, Marcus; Kumbhari, Vivek; Behzadi, Armirhossein; Behzadi, Amirali; Correia, Joao Carlos; Mohr, Friedrich Wilhelm

2017-01-01

Aims In infective endocarditis (IE), a severe inflammatory disease of the endocardium with an unchanged incidence and mortality rate over the past decades, only 1% of the cases have been described as polymicrobial infections based on microbiological approaches. The aim of this study was to identify potential biodiversity of bacterial species from infected native and prosthetic valves. Furthermore, we compared the ultrastructural micro-environments to detect the localization and distribution patterns of pathogens in IE. Material and methods Using next-generation sequencing (NGS) of 16S rDNA, which allows analysis of the entire bacterial community within a single sample, we investigated the biodiversity of infectious bacterial species from resected native and prosthetic valves in a clinical cohort of 8 IE patients. Furthermore, we investigated the ultrastructural infected valve micro-environment by focused ion beam scanning electron microscopy (FIB-SEM). Results Biodiversity was detected in 7 of 8 resected heart valves. This comprised 13 bacterial genera and 16 species. In addition to 11 pathogens already described as being IE related, 5 bacterial species were identified as having a novel association. In contrast, valve and blood culture-based diagnosis revealed only 4 species from 3 bacterial genera and did not show any relevant antibiotic resistance. The antibiotics chosen on this basis for treatment, however, did not cover the bacterial spectra identified by our amplicon sequencing analysis in 4 of 8 cases. In addition to intramural distribution patterns of infective bacteria, intracellular localization with evidence of bacterial immune escape mechanisms was identified. Conclusion The high frequency of polymicrobial infections, pathogen diversity, and intracellular persistence of common IE-causing bacteria may provide clues to help explain the persistent and devastating mortality rate observed for IE. Improved bacterial diagnosis by 16S rDNA NGS that increases the ability to tailor antibiotic therapy may result in improved outcomes. PMID:28410379

Evolutionary diversification of secondary mechanoreceptor cells in tunicata.

PubMed

Rigon, Francesca; Stach, Thomas; Caicci, Federico; Gasparini, Fabio; Burighel, Paolo; Manni, Lucia

2013-06-04

Hair cells are vertebrate secondary sensory cells located in the ear and in the lateral line organ. Until recently, these cells were considered to be mechanoreceptors exclusively found in vertebrates that evolved within this group. Evidence of secondary mechanoreceptors in some tunicates, the proposed sister group of vertebrates, has recently led to the hypothesis that vertebrate and tunicate secondary sensory cells share a common origin. Secondary sensory cells were described in detail in two tunicate groups, ascidians and thaliaceans, in which they constitute an oral sensory structure called the coronal organ. Among thaliaceans, the organ is absent in salps and it has been hypothesised that this condition is due to a different feeding system adopted by this group of animals. No information is available as to whether a comparable structure exists in the third group of tunicates, the appendicularians, although different sensory structures are known to be present in these animals. We studied the detailed morphology of appendicularian oral mechanoreceptors. Using light and electron microscopy we could demonstrate that the mechanosensory organ called the circumoral ring is composed of secondary sensory cells. We described the ultrastructure of the circumoral organ in two appendicularian species, Oikopleura dioica and Oikopleura albicans, and thus taxonomically completed the data collection of tunicate secondary sensory cells. To understand the evolution of secondary sensory cells in tunicates, we performed a cladistic analysis using morphological data. We constructed a matrix consisting of 19 characters derived from detailed ultrastructural studies in 16 tunicate species and used a cephalochordate and three vertebrate species as outgroups. Our study clearly shows that the circumoral ring is the appendicularian homologue of the coronal organ of other tunicate taxa. The cladistic analysis enabled us to reconstruct the features of the putative ancestral hair cell in tunicates, represented by a simple monociliated cell. This cell successively differentiated into the current variety of oral mechanoreceptors in the various tunicate lineages. Finally, we demonstrated that the inferred evolutionary changes coincide with major transitions in the feeding strategies in each respective lineage.

Chemical, ultrastructural and supramolecular analysis of tension wood in Populus tremula x alba as a model substrate for reduced recalcitrance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Foston, Marcus B; Hubbell, Christopher A; Samuel, Reichel

2011-01-01

Biomass is one of the most abundant potential sustainable sources for fuel and material production, however to fully realize this potential an improved understanding of lignocellulosic recalcitrance must be developed. In an effort to appreciate the underlying phenotypic, biochemical and morphological properties associated with the reduced recalcitrance observed in tension stress-induced reaction wood, we report the increased enzymatic sugar yield and corresponding chemical and ultrastructural properties of Populus tension wood. Populus tremula x alba (PTA) was grown under tension and stem segments containing three different wood types: normal wood (NW), tension wood (TW) from the elongated stem side and oppositemore » wood (OW) from the compressed stem side were collected. A variety of analytical techniques were used to describe changes occurring as a result of the tension stress-induced formation of a gelatinous cell wall layer (G-layer). For example, gel permeation chromatography (GPC) and 13C solid-state nuclear magnetic resonance (NMR) revealed that the molecular weight and crystallinity of cellulose in TW is greater than that of cellulose acquired from NW. Whole cell ionic liquid and other solid-state NMR analysis detailed the structure of lignin and hemicellulose in the samples, detecting the presence of variations in lignin and hemicellulose sub-units, linkages and semi-quantitatively estimating the relative amounts of syringyl (S), guaiacyl (G) and p-hydroxybenzoate (PB) monolignol units. It was confirmed that TW displayed an increase in PB or H-like lignin and S to G ratio from 1.25 to 1.50 when compared to the NW sample. Scanning electron microscopy (SEM) and coherent anti-Stokes Raman scattering (CARS) were also used to evaluate the morphology and corresponding spatial distribution of the major lignocellulosic components. We found changes in a combination of cell wall properties appear to influence recalcitrance more than any single factor alone.« less

Ependymal cells variations in the central canal of the rat spinal cord filum terminale: an ultrastructural investigation.

PubMed

Mitro, A; Gallatz, K; Palkovits, M; Kiss, A

2013-04-01

The ependymal cells, considered today as an active participant in neuroendocrine functions, were investigated by electron microscopy in the central canal of the lowest spinal cord, the filum terminale (FT), in adult rats. In this area of the spinal cord, the central canal is covered by a heterogeneous population of ependymal cells. The aim of the present work was to compare the regional features of the ependymal cells in two different parts of the FT with a special regard to their ultrastructure. Two parts of the FT were selected for the ultrastructural observations: the rostral (rFT) and the caudal (cFT) ones. The rTF was removed at the level of the immediate continuation of the conus medullaris, while the cFT 30 mm further caudally. After formaldehyde fixation, the spinal cord was removed and cut into small blocks for electron microscopic processing. The material was embedded into durcupan, contrasted with uranyl acetate, lead citrate as well as osmium tetroxide, and investigated under JEOL 1200 EX electron microscope. In the rFT, the ependymal lining is pseudostratified and one-layered in the cFT, whereas the shape of the ependymal cells may vary from cuboidal to flatten in the rostro-caudal direction. The basal membrane of many ependymal cells possesses deep invaginations, so called "filum terminale labyrinths". Many neuronal processes occur in the pericanalicular neuropil. In contrast to the rFT, the cFT is less rich in the neuropil particles. Some of the ependymal cells concurrently reach both the intracanalicular and extracanalicular cerebrospinal fluid (CSF), thus they may represent a new variant of the ependymal cells designated as "bridge cells of the FT". The present data indicate that the FT ependymal cells exhibit clear differences in anatomy as well as ultrastructure that may reflect their distinct functional activity. Therefore, observations presented here may serve for the better understanding of the physiological role of the individual ependymal areas in this special portion of the rat spinal cord.

Chronic cigarette smoke causes oxidative damage and apoptosis to retinal pigmented epithelial cells in mice.

PubMed

Fujihara, Masashi; Nagai, Norihiro; Sussan, Thomas E; Biswal, Shyam; Handa, James T

2008-09-01

The purpose of this study was to determine whether mice exposed to chronic cigarette smoke develop features of early age-related macular degeneration (AMD). Two month old C57Bl6 mice were exposed to either filtered air or cigarette smoke in a smoking chamber for 5 h/day, 5 days/week for 6 months. Eyes were fixed in 2.5% glutaraldehyde/2% paraformaldehyde and examined for ultrastructural changes by transmission electron microscopy. The contralateral eye was fixed in 2% paraformaldehyde and examined for oxidative injury to the retinal pigmented epithelium (RPE) by 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-OHdG) immunolabeling and apoptosis by TUNEL labeling. Mice exposed to cigarette smoke had immunolabeling for 8-OHdG in 85+/-3.7% of RPE cells counted compared to 9.5+/-3.9% in controls (p<0.00001). Bruch membrane was thicker in mice exposed to smoke (1086+/-332 nm) than those raised in air (543+/-132 nm; p = 0.0069). The two most pronounced ultrastructural changes (severity grading scale from 0-3) seen were a loss of basal infoldings (mean difference in grade = 1.98; p<0.0001), and an increase in intracellular vacuoles (mean difference in grade = 1.7; p<0.0001). Ultrastructural changes to Bruch membrane in cigarette-smoke exposed mice were smaller in magnitude but consistently demonstrated significantly higher grade injury in cigarette-exposed mice, including basal laminar deposits (mean difference in grade = 0.54; p<0.0001), increased outer collagenous layer deposits (mean difference in grade = 0.59; p = 0.002), and increased basal laminar deposit continuity (mean difference in grade = 0.4; p<0.0001). TUNEL assay showed a higher percentage of apoptotic RPE from mice exposed to cigarette smoke (average 8.0+/-1.1%) than room air (average 0+/-0%; p = 0.043). Mice exposed to chronic cigarette smoke develop evidence of oxidative damage with ultrastructural degeneration to the RPE and Bruch membrane, and RPE cell apoptosis. This model could be useful for studying the mechanism of smoke induced changes during early AMD.

The New Higher Level Classification of Eukaryotes with Emphasis on the Taxonomy of Protists

Treesearch

SINA M. ADL; ALASTAIR G. B. SIMPSON; MARK A. FARMER; ROBERT A. ANDERSEN; O. ROGER ANDERSON; JOHN R. BARTA; SAMUEL S. BOWSER; GUY BRUGEROLLE; ROBERT A. FENSOME; SUZANNE FREDERICQ; TIMOTHY Y. JAMES; SERGEI KARPOV; PAUL KUGRENS; JOHN KRUG; CHRISTOPHER E. LANE; LOUISE A. LEWIS; JEAN LODGE; DENIS H. LYNN; DAVID G. MANN; RICHARD M. MCCOURT; LEONEL MENDOZA; ØJVIND MOESTRUP; SHARON E. MOZLEY-STANDRIDGE; THOMAS A. NERAD; CAROL A. SHEARER; ALEXEY V. SMIRNOV; FREDERICK W. SPIEGEL; MAX F.J.R. TAYLOR

2005-01-01

This revision of the classification of unicellular eukaryotes updates that of Levine et al. (1980) for the protozoa and expands it to include other protists. Whereas the previous revision was primarily to incorporate the results of ultrastructural studies, this revision incorporates results from both ultrastructural research since 1980 and molecular phylogenetic...

Persistent lymphadenopathy in homosexual men: a clinical and ultrastructural study.

PubMed

Anderson, M G; Dixey, J; Key, P; Ellis, D S; Tovey, G; McCaul, T F; Murray-Lyon, I M; Gazzard, B; Lawrence, A; Evans, B

1984-04-21

Ultrastructural changes (tubuloreticular structures and tube and ring shaped forms) previously described in patients with acquired immunodeficiency syndrome (AIDS) are described for the first time in the lymph nodes and circulating lymphocytes of patients with persistent lymphadenopathy. These observations support the view that the persistent lymphadenopathy syndrome and AIDS are caused by the same transmissible agent(s).

The new higher level classification of eukaryotes with emphasis on the taxonomy of protists

Treesearch

Sina M. Adl; Alastair G.B. Simpson; Mark A. Farmer; Robert A. Andersen; O. Roger Anderson; John R. Barta; Samuel S. Bowser; Guy Brugerolle; Robert A. Fensome; Suzanne Fredericq; Timothy Y. James; Sergei Karpov; Paul Kugrens; John Krug; Christopher E. Lane; Louise A. Lewis; Jean Lodge; Denis H. Lynn; David G. Mann; Richard M. McCourt; Leonel Mendoza; Ojvind Moestrup; Sharon E. Mozley-Standridge; Thomas A. Nerad; Carol A. Shearer; Alexey V. Smirnov; Frederick W. Speigel; Max F.J.R. Taylor

2005-01-01

This revision of the classification of unicellular eukaryotes updates that of Levine et al. (1980) for the protozoa and expands it to include other protists. Whereas the previous revision was primarily to incorporate the results of ultrastructural studies, this revision incorporates results from both ultrastructural research since 1980 and molecular phylogenetic...

Ultrastructure of cells of Ulmus americana cultured in vitro and exposed to the culture filtrate of Ceratocystis ulmi

Treesearch

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 and development of the new stylets inside pre-molting first instar nymphs of the Asian citrus psyllid Diaphorina citri (Hemiptera: Liviidae)

USDA-ARS?s Scientific Manuscript database

The ultrastructure and development of new stylets was studied in pre-molting first instar nymph of Diaphorina citri. Two oval-shaped masses of cuboidal hypodermal cells, located in the cephalic region, had long extensions that ended with developing pairs of mandibular and maxillary stylets, apparent...

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

DTIC Science & Technology

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

Alteration in the ultrastructural morphology of mycelial hyphae and the dynamics of transcriptional activity of lytic enzyme genes during basidiomycete morphogenesis.

PubMed

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.

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

PubMed

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.

Selenium Deficiency Induces Autophagy in Immune Organs of Chickens.

PubMed

Khoso, Pervez Ahmed; Pan, Tingru; Wan, Na; Yang, Zijiang; Liu, Ci; Li, Shu

2017-05-01

The aim of the present study was to investigate the effects of selenium (Se) deficiency on autophagy-related genes and on ultrastructural changes in the spleen, bursa of Fabricius, and thymus of chickens. The Se deficiency group was fed a basal diet containing Se at 0.033 mg/kg and the control group was fed the same basal diet containing Se at 0.15 mg/kg. The messenger RNA (mRNA) levels of the autophagy genes microtubule-associated protein 1 light chain 3 (LC3)-I, LC3-II, Beclin 1, dynein, autophagy associated gene 5 (ATG5), and target of rapamycin complex 1 (TORC1) were assessed using real-time qPCR. The protein levels of LC3-II, Beclin 1, and dynein were investigated using western blot analysis. Furthermore, the ultrastructure was observed using an electron microscope. The results indicated that spleen mRNA levels of LC3-I, LC3-II, Beclin 1, dynein, ATG5, and TORC1 and the protein levels of LC3-II, Beclin 1, and dynein were increased in the Se deficiency group compared with the control group. In the bursa of Fabricius, the mRNA levels of LC3-I, LC3-II, Beclin 1, dynein, ATG5, and TORC1 and the protein levels of Beclin 1 and dynein were increased; furthermore, the protein level of LC3-II was decreased in the Se deficiency group compared to the control group. In the thymus, the mRNA levels of LC3-I, Beclin 1, and ATG5 increased; the levels of LC3-II, dynein, and TORC1 were decreased; the protein level of Beclin 1 increased; and the levels of LC3-II and dynein decreased in the Se deficiency group compared to those in the control group. Further cellular morphological changes, such as autophagy vacuoles, autolysosomes, and lysosomal degradation, were observed in the spleen, bursa of Fabricius, and thymus of the Se-deficiency group. In summary, Se deficiency caused changes in autophagy-related genes, which increased the autophagic process and also caused structural damages to the immune organs of chickens.

Ultrastructure of potato tubers formed in microgravity under controlled environmental conditions

NASA Technical Reports Server (NTRS)

Cook, Martha E.; Croxdale, Judith G.; Tibbitts, T. W. (Principal Investigator)

2003-01-01

Previous spaceflight reports attribute changes in plant ultrastructure to microgravity, but it was thought that the changes might result from growth in uncontrolled environments during spaceflight. To test this possibility, potato explants were examined (a leaf, axillary bud, and small stem segment) grown in the ASTROCULTURETM plant growth unit, which provided a controlled environment. During the 16 d flight of space shuttle Columbia (STS-73), the axillary bud of each explant developed into a mature tuber. Upon return to Earth, tuber slices were examined by transmission electron microscopy. Results showed that the cell ultrastructure of flight-grown tubers could not be distinguished from that of tuber cells grown in the same growth unit on the ground. No differences were observed in cellular features such as protein crystals, plastids with starch grains, mitochondria, rough ER, or plasmodesmata. Cell wall structure, including underlying microtubules, was typical of ground-grown plants. Because cell walls of tubers formed in space were not required to provide support against the force due to gravity, it was hypothesized that these walls might exhibit differences in wall components as compared with walls formed in Earth-grown tubers. Wall components were immunolocalized at the TEM level using monoclonal antibodies JIM 5 and JIM 7, which recognize epitopes of pectins, molecules thought to contribute to wall rigidity and cell adhesion. No difference in presence, abundance or distribution of these pectin epitopes was seen between space- and Earth-grown tubers. This evidence indicates that for the parameters studied, microgravity does not affect the cellular structure of plants grown under controlled environmental conditions.

Drying techniques for the visualisation of agarose-based chromatography media by scanning electron microscopy.

PubMed

Nweke, Mauryn C; Turmaine, Mark; McCartney, R Graham; Bracewell, Daniel G

2017-03-01

The drying of chromatography resins prior to scanning electron microscopy is critical to image resolution and hence understanding of the bead structure at sub-micron level. Achieving suitable drying conditions is especially important with agarose-based chromatography resins, as over-drying may cause artefact formation, bead damage and alterations to ultrastructural properties; and under-drying does not provide sufficient resolution for visualization under SEM. This paper compares and contrasts the effects of two drying techniques, critical point drying and freeze drying, on the morphology of two agarose based resins (MabSelect™/d w ≈85 µm and Capto™ Adhere/d w ≈75 µm) and provides a complete method for both. The results show that critical point drying provides better drying and subsequently clearer ultrastructural visualization of both resins under SEM. Under this protocol both the polymer fibers (thickness ≈20 nm) and the pore sizes (diameter ≈100 nm) are clearly visible. Freeze drying is shown to cause bead damage to both resins, but to different extents. MabSelect resin encounters extensive bead fragmentation, whilst Capto Adhere resin undergoes partial bead disintegration, corresponding with the greater extent of agarose crosslinking and strength of this resin. While freeze drying appears to be the less favorable option for ultrastructural visualization of chromatography resin, it should be noted that the extent of fracturing caused by the freeze drying process may provide some insight into the mechanical properties of agarose-based chromatography media. © 2017 The Authors. Biotechnology Journal published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Comparative ultrastructural study of spermatozoa in some oyster species from the Asian-Pacific Coast.

PubMed

Yurchenko, Olga V

2012-02-01

Sperm organization in the oysters Crassostrea gigas, Crassostrea nippona, Crassostrea cf. rivularis and Saccostrea cf. mordax inhabiting Asian Pacific coast was studied. The spermatozoa of all studied species had a number of common morphological characters such as a cup-like acrosome with heterogeneous matrix on its top, an axial rod in the subacrosomal space, a barrel-shaped nucleus, four mitochondria in the midpiece, pericentriolar complexes, and a 9+2-organized flagellum. The spermatozoa of C. cf. rivularis differed from the other species by having cytoplasm processes in the midpiece region. Such structures have never been described in the Ostreidae. Additionally, each species could be identified by the shape and size of sperm compartments (acrosome, nucleus, anterior nuclear fossa). The most significant interspecific difference was found in the size of an anterior nuclear fossa. The smallest anterior nuclear fossa was found in C. cf. rivularis (about 0.24 μm in length reaching about 22% of the nuclear length) while the biggest in C. gigas from the Sea of Japan (about 0.53 μm in length reaching about 46% of the nuclear length). The spermatozoa of C. gigas collected from the Sea of Japan and Taiwan Strait differed significantly in almost all the studied parameters. Since sperm morphology has been successfully used for species differentiation, this suggests the existence of two species rather than two populations. The data obtained indicate the species-specific difference in the sperm ultrastructure within the Ostreidae, which may be identified both ultrastructurally and morphometrically. Copyright © 2011 Elsevier Ltd. All rights reserved.

Pollen structure and development in Nymphaeales: insights into character evolution in an ancient angiosperm lineage.

PubMed

Taylor, Mackenzie L; Cooper, Ranessa L; Schneider, Edward L; Osborn, Jeffrey M

2015-10-01

A knowledge of pollen characters in early-diverging angiosperm lineages is essential for understanding pollen evolution and the role of pollen in angiosperm diversification. In this paper, we report and synthesize data on mature pollen and pollen ontogeny from all genera of Nymphaeales within a comparative, phylogenetic context and consider pollen evolution in this early-diverging angiosperm lineage. We describe mature pollen characters for Euryale, Barclaya, and Nymphaea ondinea, taxa for which little to no structural data exist. We studied mature pollen for all nymphaealean genera using light, scanning electron, and transmission electron microscopy. We reviewed published reports of nymphaealean pollen to provide a comprehensive discussion of pollen characters in water lilies. Nymphaeales exhibit diversity in key pollen characters, including dispersal unit size, ornamentation, aperture morphology, and tapetum type. All Nymphaeales pollen are tectate-columellate, exhibiting one of two distinct patterns of infratectal ultrastructure-a thick infratectal space with robust columellae or a thin infratectal space with thin columellae. All genera have pollen with a lamellate endexine that becomes compressed in the proximal, but not distal wall. This endexine ultrastructure supports the operculate hypothesis for aperture origin. Nymphaeaceae pollen exhibit a membranous granular layer, which is a synapomorphy of the family. Variation in pollen characters indicates that significant potential for lability in pollen development was present in Nymphaeales at the time of its divergence from the rest of angiosperms. Structural and ontogenetic data are essential for interpreting pollen characters, such as infratectum and endexine ultrastructure in Nymphaeales. © 2015 Botanical Society of America.

Non-Fourier thermal transport induced structural hierarchy and damage to collagen ultrastructure subjected to laser irradiation.

PubMed

Sahoo, Nilamani; Narasimhan, Arunn; Dhar, Purbarun; Das, Sarit K

2018-05-01

Comprehending the mechanism of thermal transport through biological tissues is an important factor for optimal ablation of cancerous tissues and minimising collateral tissue damage. The present study reports detailed mapping of the rise in internal temperature within the tissue mimics due to NIR (1064 nm) laser irradiation, both for bare mimics and with gold nanostructures infused. Gold nanostructures such as mesoflowers and nanospheres have been synthesised and used as photothermal converters to enhance the temperature rise, resulting in achieving the desired degradation of malignant tissue in targeted region. Thermal history was observed experimentally and simulated considering non-Fourier dual phase lag (DPL) model incorporated Pennes bio-heat transfer equation using COMSOL Multiphysics software. The gross deviation in temperature i.e. rise from the classical Fourier model for bio-heat conduction suggests additional effects of temperature rise on the secondary structures and morphological and physico-chemical changes to the collagen ultrastructures building the tissue mass. The observed thermal denaturation in the collagen fibril morphologies have been explained based on the physico-chemical structure of collagen and its response to thermal radiation. The large shift in frequency of amides A and B is pronounced at a depth of maximum temperature rise compared with other positions in tissue phantom. Observations for change in band of amide I, amide II, and amide III are found to be responsible for damage to collagen ultra-structure. Variation in the concentration of gold nanostructures shows the potentiality of localised hyperthermia treatment subjected to NIR radiation through a proposed free radical mechanism.

Amniotic membrane scaffolds enable the development of tissue-engineered urothelium with molecular and ultrastructural properties comparable to that of native urothelium.

PubMed

Jerman, Urška Dragin; Veranič, Peter; Kreft, Mateja Erdani

2014-04-01

The amniotic membrane (AM) is a naturally derived biomaterial that possesses biological and mechanical properties of great importance for tissue engineering. The aim of our study was to determine whether the AM enables the formation of a normal urinary bladder epithelium-urothelium--and to reveal any differences in the urothelial cell (UC) growth and differentiation when using different AM scaffolds. Cryopreserved human AM was used as a scaffold in three different ways. Normal porcine UCs were seeded on the AM epithelium (eAM), denuded AM (dAM), and stromal AM (sAM) and were cultured for 3 weeks. UC growth on AM scaffolds was monitored daily. By using electron microscopy, histochemical and immunofluorescence techniques, we here provide evidence that all three AM scaffolds enable the development of the urothelium. The fastest growth and the highest differentiation of UCs were demonstrated on the sAM scaffold, which enables the development of tissue-engineered urothelium with molecular and ultrastructural properties comparable to that of the native urothelium. Most importantly, the highly differentiated urothelia on the sAM scaffolds provide important experimental models for future drug delivery studies and developing tissue engineering strategies considering that subtle differences are identified before translation to the clinical settings.

Ultrastructural Alterations of Von Economo Neurons in the Anterior Cingulate Cortex in Schizophrenia.

PubMed

Krause, Martin; Theiss, Carsten; Brüne, Martin

2017-11-01

Von Economo neurons (VENs) are large bipolar projection neurons mainly located in layer Vb of anterior cingulate cortex (ACC) and anterior insula. Both regions are involved in cognitive and emotional procedures and are functionally and anatomically altered in schizophrenia. Although the detailed function of VEN remains unclear, it has been suggested that these neurons are involved in the pathomechanism of schizophrenia. Here, we were interested in the question whether or not the VEN of schizophrenia patients would show abnormalities at the ultrastructural level. Accordingly, we examined the amount of lysosomal aggregations of the VEN in post-mortem tissue of patients with schizophrenia, bipolar disorder and psychologically unaffected individuals, and compared the findings with aggregations in adjacent pyramidal cells in layer Vb of the ACC. VEN of patients with schizophrenia, and to a lesser degree individuals with bipolar disorder contained significantly more lysosomal aggregations compared with tissue from unaffected controls. Specifically, the larger amount of lysosomal aggregations in schizophrenia seemed to be selective for VEN, with no differences occurring in pyramidal cells. These findings may indicate that the VEN of schizophrenia patients are selectively vulnerable to neuronal damage. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 300:2017-2024, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Touch-plate and statolith formation in graviceptors of ephyrae which developed while weightless in space

NASA Technical Reports Server (NTRS)

Spangenberg, D. B.; Coccaro, E.; Schwarte, R.; Lowe, B.

1996-01-01

Ultrastructural studies of the statocysts and touch-plates of graviceptors (rhopalia) of Aurelia ephyrae revealed that (1) touch-plate hair cells are present; and (2) cytoplasmic strands from the hair cell bases extend from the neurite plexus to touch similar strands from the lithocytes. This close association of hair cell neurites and statocysts may have important implications regarding the transmitting and processing of positional information with respect to the gravity vector. Graviceptors of ephyrae which developed while weightless in microgravity were compared with controls at the ultrastructural level. We found that hair cells of ephyrae which developed in microgravity had fewer lipid droplets in the large spaces near their bases as compared with 1 g controls. In the ephyrae from the first microgravity experiment, hair cells had more large apical vacuoles with filamentous content than were found in hair cells of ephyrae from the second experiment and controls. The neurite plexus and the network of cytoplasmic strands extending to the statocysts were not different in microgravity-developed ephyrae from controls. Behavioral differences in swimming and orienting in ephyrae in microgravity and controls (reported earlier) were not explained by morphological differences in the hair cells of the touch-plates or the statocysts, although functional differences apparently occurred.

Comparative Ultrastructure and Carbohydrate Composition of Gastroliths from Astacidae, Cambaridae and Parastacidae Freshwater Crayfish (Crustacea, Decapoda)

PubMed Central

Luquet, Gilles; Fernández, María S.; Badou, Aïcha; Guichard, Nathalie; Roy, Nathalie Le; Corneillat, Marion; Alcaraz, Gérard; Arias, José L.

2012-01-01

Crustaceans have to cyclically replace their rigid exoskeleton in order to grow.Most of them harden this skeleton by a calcification process. Some decapods (land crabs, lobsters and crayfish) elaborate calcium storage structures as a reservoir of calcium ions in their stomach wall, as so-called gastroliths. For a better understanding of the cyclic elaboration of these calcium deposits, we studied the ultrastructure of gastroliths from freshwater crayfish by using a combination of microscopic and physical techniques. Because sugars are also molecules putatively involved in the elaboration process of these biomineralizations, we also determined their carbohydrate composition. This study was performed in a comparative perspective on crayfish species belonging to the infra-order Astacidea (Decapoda, Malacostraca): three species from the Astacoidea superfamily and one species from the Parastacoidea superfamily. We observed that all the gastroliths exhibit a similar dense network of protein-chitin fibers, from macro- to nanoscale, within which calcium is precipitated as amorphous calcium carbonate. Nevertheless, they are not very similar at the molecular level, notably as regards their carbohydrate composition. Besides glucosamine, the basic carbohydrate component of chitin, we evidenced the presence of other sugars, some of which are species-specific like rhamnose and galacturonic acid whereas xylose and mannose could be linked to proteoglycan components. PMID:24970155

Evidence for a composite organic-inorganic fabric of belemnite rostra: implication for palaeoceanography

NASA Astrophysics Data System (ADS)

Hoffmann, Rene; Richter, Detlev K.; Neuser, Rolf D.; Jöns, Niels; Linzmeier, Benjamin J.; Lemanis, Robert E.; Fusseis, Florian; Xiao, Xianghui; Immenhauser, Adrian

2017-04-01

Carbonate skeletons of fossil marine organisms are widely used to reconstruct palaeoenvironments. Specifically, the geochemistry of Jurassic and Cretaceous belemnite rostra is commonly applied to reconstruct palaeoseawater properties. This is due to the assumption that belemnites, as member of the mollusc group, precipitated their rostra in equilibrium with the palaeoenvironment and secondly it was assumed that rostra represent primary dense low Mg calcite structures and relatively stable against diagenetic overprinting. More recently an increasing number of published data, show significant scatter in geochemical data (e.g., d18O, d13C, element/Ca ratio) when comparing belemnite rostra from the same stratigraphic level or within a single belemnite rostrum. This scatter is not explained by differential diagenetic overprint alone but also by vertical and horizontal migration patterns, seasonality, or changes in salinity. In order to test for an ultrastructural-related explanation for the observed scatter we employed a wide range of state-of-the-art analytical tools, e.g., cathodoluminescence, fluorescence- and confocal laser fluorescence microscopy, scanning electron microscopy equipped with a backscatter detector, electron microprobe analysis, electron backscatter diffraction imaging to thin sections and ultra-thin sections of well-preserved specimens. We found petrographic evidence that the primary, i.e. biogenic, ultrastructure of rostra of Megateuthis (Middle Jurassic) and Belemnitella and Gonioteuthis (Late Cretaceous) was not a dense calcite structure, but contained primary porosity. The biogenic ultrastructure consists of a filigree framework of tetrahedrons of variable size with branches forming a honeycomb-like network. Data presented here suggest that these rostra yielded as much as 50 to 90% primary pore space. We propose that the pore space was originally filled with body fluid and/or organic compounds during the life time of these organisms in analogy with modern cephalopods. Intra-rostral porosity was occluded post mortem by earliest diagenetic isopachous calcite cements of a non-biogenic origin. These may have been precipitated due to increased alkalinity related to the decay of organic matter. If this holds true, then the resulting fabric represents a composite biogenic/abiogenic structure precipitated at different times and depths in the water column. We suggest that these findings have significance for those using belemnite rostra as archives of their palaeoenvironment, for the reconstruction of belemnite palaeoecology, and for the functional interpretation of belemnite rostra.

Ultrastructural studies of vasopressin neurons of the paraventricular nucleus of the hypothalamus using a monoclonal antibody to vasopressin: analysis of synaptic input.

PubMed

Silverman, A J; Hou-Yu, A; Zimmerman, E A

1983-05-01

The ultrastructure of the vasopressin neurons of the paraventricular nucleus of the hypothalamus was studied by immunocytochemical techniques. Tissue antigen was detected in unembedded tissue sections using a monoclonal antibody that recognizes vasopressin but not oxytocin or vasotocin. At the light-microscopic level, reaction product was seen to fill the cytoplasm of the neuron cell body as well as large portions of the dendrite and axon. Immunoreactive spines were seen on both somatic and dendritic surfaces and their presence was confirmed at the ultrastructural level. In the light-microscope, axonal processes do not have spines and are thinner and more varicose than dendritic processes. At the electron-microscopic level, both axons and dendrites of the vasopressin cells are filled with reactive neurosecretory granules. The presence of large numbers of these organelles made it difficult to distinguish proximal dendrites from Herring bodies (axonal swellings). At the ultrastructural level, reaction product was also observed in the cytoplasm of all segments of the vasopressin cells. The presence of reaction product outside of membranous compartments is undoubtably due to disruption of membranes by detergent treatment or exposure to basic pH. However, the staining procedure used did allow us to examine the synaptic input to the vasopressin cells. All portions of the vasopressin neuron receive a diverse innervation. The somata have synapses on their surfaces and on spines. These axo-somatic terminals are primarily, but not exclusively, symmetrical and the presynaptic elements contain spherical or elongate vesicles. On the dendrites, terminals again were observed on the surface or on spines. these axo-dendritic synapses were usually asymmetrical. The presynaptic elements contained clear spherical, elongate or pleomorphic vesicles. Occasional varicosities with dense-core granules were seen to make en passant contacts with dendrites; these contacts did not have obvious membrane specializations. Input to vasopressin axons was studied both along the paraventricular-neurohypophysial tract and in the median eminence. Vasopressin axons receive a synaptic input (axo-axonic), predominately of the asymmetric variety with clear, spherical vesicles in the presynaptic element. These findings demonstrate that the vasopressin neurons of the paraventricular nucleus receive a diverse innervation.

Lysis of autologous human macrophages by lymphokine-activated killer cells: interaction of effector cell and target cell conjugates analyzed by scanning electron microscopy.

PubMed

Streck, R J; Helinski, E H; Ovak, G M; Pauly, J L

1990-09-01

Lymphokine (i.e., interleukin 2; IL-2)-activated killer (LAK) cells derived from normal human blood are known to destroy human tumor target cells. Accordingly, immunotherapy modalities using IL-2, either alone or in combination with LAK cells, have been evaluated for eradicating metastatic cancer. In studies conducted to characterize receptors on LAK cell membrane ultrastructures, we observed that LAK cells kill autologous human monocyte-derived macrophages (M phi). In these experiments, peripheral blood mononuclear cells of a healthy adult donor were cultured to generate LAK cells and autologous non-adherent M phi. Thereafter, conjugates were prepared by incubating for 3 h autologous populations of LAK cells and M phi. Examination of the conjugates by scanning electron microscopy (SEM) identified LAK cell-mediated killing of M phi. Moreover, SEM analysis of the LAK cell membrane architecture identified microvilli-like ultrastructures that provided a physical bridge that joined together the LAK cell and M phi. The immunological mechanism(s) underling LAK cell killing of autologous M phi is not known; nevertheless, these conjugates will provide a useful model to study membrane receptors on ultrastructures that mediate the initial stages of cytolysis that include target cell recognition and cell-to-cell adhesion. The results of our observations and the findings of other investigators who have also demonstrated LAK cell killing of autologous normal human leukocytes are discussed in the context of the association of IL-2 and IL-2-activated killer cells with side effects observed in ongoing clinical trials and with autoimmune disorders.

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

PubMed

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.

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

PubMed Central

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

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. 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. PMID:25425979

Novel features of Brassica napus embryogenic microspores revealed by high pressure freezing and freeze substitution: evidence for massive autophagy and excretion-based cytoplasmic cleaning.

PubMed

Corral-Martínez, Patricia; Parra-Vega, Verónica; Seguí-Simarro, Jose M

2013-07-01

Induction of embryogenesis from isolated microspore cultures is a complex experimental system where microspores undergo dramatic changes in developmental fate. After ~40 years of application of electron microscopy to the study of the ultrastructural changes undergone by the induced microspore, there is still room for new discoveries. In this work, high pressure freezing and freeze substitution (HPF/FS), the best procedures known to date for ultrastructural preservation, were used to process Brassica napus microspore cultures covering all the stages of microspore embryogenesis. Analysis of these cultures by electron microscopy revealed massive processes of autophagy exclusively in embryogenic microspores, but not in other microspore-derived structures also present in cultures. However, a significant part of the autophagosomal cargo was not recycled. Instead, it was transported out of the cell, producing numerous deposits of extracytoplasmic fibrillar and membranous material. It was shown that commitment of microspores to embryogenesis is associated with both massive autophagy and excretion of the removed material. It is hypothesized that autophagy would be related to the need for a profound cytoplasmic cleaning, and excretion would be a mechanism to avoid excessive growth of the vacuolar system. Together, the results also demonstrate that the application of HPF/FS to the study of the androgenic switch is the best option currently available to identify the complex and dramatic ultrastructural changes undergone by the induced microspore. In addition, they provide significant insights to understand the cellular basis of induction of microspore embryogenesis, and open a new door for the investigation of this intriguing developmental pathway.

Oral astringent stimuli alter the enamel pellicle's ultrastructure as revealed by electron microscopy.

PubMed

Rehage, Melanie; Delius, Judith; Hofmann, Thomas; Hannig, Matthias

2017-08-01

This electron microscopic study aimed at investigating effects of oral astringent stimuli on the enamel pellicle's morphology. Pellicles were formed in situ within 30min on bovine enamel slabs, fixed to individuals' upper jaw splints. The pellicle-coated specimens were immersed in vitro in seven diverse astringent solutions and subsequently analyzed by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, as well as transmission electron microscopy (TEM). Four biocompatible astringents, namely the polyphenol epigallocatechin gallate, the metal salt iron(III) sulfate, the basic protein lysozyme, and the aminopolysaccharide chitosan, were additionally applied in situ. After rinsing the oral cavity with these compounds, the pellicle's ultrastructure was imaged by SEM and TEM, respectively. Untreated pellicle samples served as controls. Exposure to polyphenols and lysozyme induced particularly thicker and electron-denser pellicles in comparison to the control pellicle with similar characteristics in vitro and in situ. In contrast, acidic chitosan and metal salt solutions, respectively, revealed minor pellicle alterations. The incorporation of Fe and Al into the pellicles treated with the corresponding inorganic salts was verified by EDX analysis. Astringent-induced pellicle modifications were for the first time visualized by TEM. The ultrastructural alterations of the dental pellicle may partly explain the tooth-roughening effect caused by oral astringent stimuli. Astringents might modify the pellicle's protective properties against dental erosion, attrition, as well as bacterial adhesion, and by this means may influence tooth health. The findings may thus be particularly relevant for preventive dentistry. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

PubMed

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.

Simultaneous cathodoluminescence and electron microscopy cytometry of cellular vesicles labeled with fluorescent nanodiamonds.

PubMed

Nagarajan, Sounderya; Pioche-Durieu, Catherine; Tizei, Luiz H G; Fang, Chia-Yi; Bertrand, Jean-Rémi; Le Cam, Eric; Chang, Huan-Cheng; Treussart, François; Kociak, Mathieu

2016-06-02

Light and Transmission Electron Microscopies (LM and TEM) hold potential in bioimaging owing to the advantages of fast imaging of multiple cells with LM and ultrastructure resolution offered by TEM. Integrated or correlated LM and TEM are the current approaches to combine the advantages of both techniques. Here we propose an alternative in which the electron beam of a scanning TEM (STEM) is used to excite concomitantly the luminescence of nanoparticle labels (a process known as cathodoluminescence, CL), and image the cell ultrastructure. This CL-STEM imaging allows obtaining luminescence spectra and imaging ultrastructure simultaneously. We present a proof of principle experiment, showing the potential of this technique in image cytometry of cell vesicular components. To label the vesicles we used fluorescent diamond nanocrystals (nanodiamonds, NDs) of size ≈150 nm coated with different cationic polymers, known to trigger different internalization pathways. Each polymer was associated with a type of ND with a different emission spectrum. With CL-STEM, for each individual vesicle, we were able to measure (i) their size with nanometric resolution, (ii) their content in different ND labels, and realize intracellular component cytometry. In contrast to the recently reported organelle flow cytometry technique that requires cell sonication, CL-STEM-based image cytometry preserves the cell integrity and provides a much higher resolution in size. Although this novel approach is still limited by a low throughput, the automatization of data acquisition and image analysis, combined with improved intracellular targeting, should facilitate applications in cell biology at the subcellular level.

Chondrogenesis, osteogenesis and adipogenesis of canine mesenchymal stem cells: a biochemical, morphological and ultrastructural study.

PubMed

Csaki, C; Matis, U; Mobasheri, A; Ye, H; Shakibaei, M

2007-12-01

Musculoskeletal diseases with osteochondrotic articular cartilage defects, such as osteoarthritis, are an increasing problem for humans and companion animals which necessitates the development of novel and improved therapeutic strategies. Canine mesenchymal stem cells (cMSCs) offer significant promise as a multipotent source for cell-based therapies and could form the basis for the differentiation and cultivation of tissue grafts to replace damaged tissue. However, no comprehensive analysis has been undertaken to characterize the ultrastructure of in vitro differentiated cMSCs. The main goal of this paper was to focus on cMSCs and to analyse their differentiation capacity. To achieve this aim, bone marrow cMSCs from three canine patients were isolated, expanded in monolayer culture and characterized with respect to their ability for osteogenic, adipogenic and chondrogenic differentiation capacities. cMSCs showed proliferative potential and were capable of osteogenic, adipogenic and chondrogenic differentiation. cMSCs treated with the osteogenic induction medium differentiated into osteoblasts, produced typical bone matrix components, beta1-integrins and upregulated the osteogenic specific transcription factor Cbfa-1. cMSCs treated with the adipogenic induction medium showed typical adipocyte morphology, produced adiponectin, collagen type I and beta1-integrins, and upregulated the adipogenic specific transcription factor PPAR-gamma. cMSCs treated with the chondrogenic induction medium exhibited a round to oval shape, produced a cartilage-specific extracellular matrix, beta1-integrins and upregulated the chondrogenic specific transcription factor Sox9. These results demonstrate, at the biochemical, morphological and ultrastructural levels, the multipotency of cMSCs and thus highlight their potential therapeutic value for cell-based tissue engineering.

A combined morphological, ultrastructural, molecular, and biochemical study of the peculiar family Gomontiellaceae (Oscillatoriales) reveals a new cylindrospermopsin-producing clade of cyanobacteria.

PubMed

Bohunická, Markéta; Mareš, Jan; Hrouzek, Pavel; Urajová, Petra; Lukeš, Martin; Šmarda, Jan; Komárek, Jiří; Gaysina, Lira A; Strunecký, Otakar

2015-12-01

Members of the morphologically unusual cyanobacterial family Gomontiellaceae were studied using a polyphasic approach. Cultured strains of Hormoscilla pringsheimii, Starria zimbabweënsis, Crinalium magnum, and Crinalium epipsammum were thoroughly examined, and the type specimen of the family, Gomontiella subtubulosa, was investigated. The results of morphological observations using both light microscopy and transmission electron microscopy were consistent with previous reports and provided evidence for the unique morphological and ultrastructural traits of this family. Analysis of the 16S rRNA gene confirmed the monophyletic origin of non-marine repre-sentatives of genera traditionally classified into this family. The family was phylogenetically placed among other groups of filamentous cyanobacterial taxa. The presence of cellulose in the cell wall was analyzed and confirmed in all cultured Gomontiellaceae members using Fourier transform infrared spectroscopy and fluorescence microscopy. Evaluation of toxins produced by the studied strains revealed the hepatotoxin cylindrospermopsin (CYN) in available strains of the genus Hormoscilla. Production of this compound in both Hormoscilla strains was detected using high-performance liquid chromatography in tandem with high resolution mass spectrometry and confirmed by positive PCR amplification of the cyrJ gene from the CYN biosynthetic cluster. To our knowledge, this is the first report of CYN production by soil cyanobacteria, establishing a previously unreported CYN-producing lineage. This study indicates that cyanobacteria of the family Gomontiellaceae form a separate but coherent cluster defined by numerous intriguing morphological, ultrastructural, and biochemical features, and exhibiting a toxic potential worthy of further investigation. © 2015 Phycological Society of America.

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

PubMed

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.

A new method for isolation of polyethylene wear debris from tissue and synovial fluid.

PubMed

Visentin, Manuela; Stea, Susanna; Squarzoni, Stefano; Antonietti, Barbara; Reggiani, Matteo; Toni, Aldo

2004-11-01

Sub-micron-sized ultrahigh molecular-weight polyethylene (PE) debris is generated in the joint space as a result of articulation and cyclic loading of an orthopaedic implant. Its characterization requires isolation and subsequent analysis by ultra-structural methods. An innovative method based on the digestion of paraffin-embedded tissue samples was proposed. Tissue slices were digested with sodium hypochlorite directly on polycarbonate filter. The same procedure could be applied also to fresh synovial fluid. Plastic particles were not lost or damaged during treatment. Chemical identification of particles was done by micro-Raman spectroscopy that confirmed purity of retrieved PE particles. Size and shape of PE particles were characterised using scanning electron microscopy and were comparable in number and morphology to the retrieval by other authors. Equivalent diameter ranged from 0.48 to 0.95microm and particle number ranged from 9 to 23x10(9)/cm(3).

A Model for the Ultrastructure of Bone Based on Electron Microscopy of Ion-Milled Sections

PubMed Central

McNally, Elizabeth A.; Schwarcz, Henry P.; Botton, Gianluigi A.; Arsenault, A. Larry

2012-01-01

The relationship between the mineral component of bone and associated collagen has been a matter of continued dispute. We use transmission electron microscopy (TEM) of cryogenically ion milled sections of fully-mineralized cortical bone to study the spatial and topological relationship between mineral and collagen. We observe that hydroxyapatite (HA) occurs largely as elongated plate-like structures which are external to and oriented parallel to the collagen fibrils. Dark field images suggest that the structures (“mineral structures”) are polycrystalline. They are approximately 5 nm thick, 70 nm wide and several hundred nm long. Using energy-dispersive X-ray analysis we show that approximately 70% of the HA occurs as mineral structures external to the fibrils. The remainder is found constrained to the gap zones. Comparative studies of other species suggest that this structural motif is ubiquitous in all vertebrates. PMID:22272230

Correlative Fluorescence and Electron Microscopy

PubMed Central

Schirra, Randall T.; Zhang, Peijun

2014-01-01

Correlative fluorescence and electron microscopy (CFEM) is a multimodal technique that combines dynamic and localization information from fluorescence methods with ultrastructural data from electron microscopy, to give new information about how cellular components change relative to the spatiotemporal dynamics within their environment. In this review, we will discuss some of the basic techniques and tools of the trade for utilizing this attractive research method, which is becoming a very powerful tool for biology labs. The information obtained from correlative methods has proven to be invaluable in creating consensus between the two types of microscopy, extending the capability of each, and cutting the time and expense associate with using each method separately for comparative analysis. The realization of the advantages of these methods in cell biology have led to rapid improvement in the protocols and have ushered in a new generation of instruments to reach the next level of correlation – integration. PMID:25271959

Precooling and ozone treatments affects postharvest quality of black mulberry (Morus nigra) fruits.

PubMed

Han, Qiang; Gao, Haiyan; Chen, Hangjun; Fang, Xiangjun; Wu, Weijie

2017-04-15

Mulberry (Morus spp.) fruits are delicious and nutritious, but they are highly perishable and have a very short shelf-life for sale in the market. This study investigated the effect and mechanisms of 2ppm ozone and precooling treatments on the postharvest quality of mulberry fruit during refrigerated storage. The results revealed that mulberry fruit subjected to ozone and precooling treatment had higher levels of titratable acidity and total soluble solids content, better retention in firmness and color, and lower decay rate, respiratory intensity, and polyphenol oxidase activity compared to the control. From the analysis of cell ultrastructure and cell wall components of fruit, ozone and precooling treatments also induced shrinkage of the stomata in the epidermis, inhibited bacteria invasion, reduced water transpiration, and delayed the decomposition of the cell walls and the degradation of epidermal tissues. Copyright © 2016. Published by Elsevier Ltd.

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

PubMed

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.

Kindler syndrome: a study of five Egyptian cases with evaluation of severity.

PubMed

Nofal, Eman; Assaf, Magda; Elmosalamy, Khaled

2008-07-01

Kindler syndrome (KS) is a rare genodermatosis characterized by four major features (acral blisters, photosensitivity, poikiloderma, and cutaneous atrophy) and many associated findings. The diagnosis of KS includes clinical features, ultrastructural findings, and, recently, immunostaining and genetic studies. Varying degrees of severity of the syndrome have been described. Five patients with clinical features consistent with KS were included in this study. All patients were subjected to histopathologic and ultrastructural studies. Cases 1 and 2 presented with severe major features, severe mucosal involvement, and many other associated findings. Case 3 presented with severe major features, but mild and limited mucosal involvement and other associated findings. Cases 4 and 5 showed mild major features and few other findings. Histopathology revealed nonspecific poikiloderma. Marked thickening of the lamina densa and splitting of the lamina lucida were the main ultrastructural findings. KS may be classified into mild, moderate, and severe according to the severity of the major features and mucosal involvement. Because histopathologic and ultrastructural findings are not pathognomonic, clinical features remain the mainstay for the diagnosis of KS, and the need for immunostaining with kindlin antibody and genetic studies may be restricted to early cases with incomplete features.

Comparison of ultrastructural and nanomechanical signature of platelets from acute myocardial infarction and platelet activation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Aiqun; Chen, Jianwei; Liang, Zhi-Hong

Acute myocardial infarction (AMI) initiation and progression follow complex molecular and structural changes in the nanoarchitecture of platelets. However, it remains poorly understood how the transformation from health to AMI alters the ultrastructural and biomechanical properties of platelets within the platelet activation microenvironment. Here, we show using an atomic force microscope (AFM) that platelet samples, including living human platelets from the healthy and AMI patient, activated platelets from collagen-stimulated model, show distinct ultrastructural imaging and stiffness profiles. Correlative morphology obtained on AMI platelets and collagen-activated platelets display distinct pseudopodia structure and nanoclusters on membrane. In contrast to normal platelets, AMImore » platelets have a stiffer distribution resulting from complicated pathogenesis, with a prominent high-stiffness peak representative of platelet activation using AFM-based force spectroscopy. Similar findings are seen in specific stages of platelet activation in collagen-stimulated model. Further evidence obtained from different force measurement region with activated platelets shows that platelet migration is correlated to the more elasticity of pseudopodia while high stiffness at the center region. Overall, ultrastructural and nanomechanical profiling by AFM provides quantitative indicators in the clinical diagnostics of AMI with mechanobiological significance.« less

Ultrastructure and Transport-Related Enzymes of the Gills and Coxal Gland of the Horseshoe Crab Limulus polyphemus.

PubMed

Henry, R P; Jackson, S A; Mangum, C P

1996-10-01

The horseshoe crab, Limulus polyphemus, may be unique among marine arthropods in that both its book gills and its coxal gland may serve as sites of ion transport. We have therefore examined the ultrastructure of these organs, as well as the distribution and relative levels of two major transport-related enzymes: the Na+ + K+ ATPase and carbonic anhydrase (CA). The ventral surface of the central region of each lamella shows the typical ultrastructural specializations for ion transport: 10 μm cell thickness, an extensive network of tubules originating from infoldings of the basal membrane, and a high density of mitochondria. This region also contains high levels of activity of the Na+ + K+ ATPase and CA. The distribution of ion transporting epithelium and transport enzymes is identical in each of the five gill books. The peripheral region of the lamellae of each gill book is specialized for passive gas exchange. The ultrastructural and biochemical profile of the coxal gland is similar to that of the central-ventral region of the gill. Limulus possesses the same general mechanism of ion regulation seen in euryhaline decapod crustaceans, but the structural and functional components are uniquely distributed.

A Combination Histochemical and Autoradiographic Method for Analysis of Enzymatic and Proliferative Responses to Immunoreactive Osteoinducer

DTIC Science & Technology

1988-01-15

DNA replication and alkaline phosphate activity in the responding cells was shown to result in effective differential labeling of these features in mildly fixed tissue sections. Application of this method with monoclonal antibodies specific for induction-associated determinants and with modifications to permit ultrastructural analyses may provide important information relevant to the mechanism of matrix-induced bone formation. Keywords: Osteogenic implants; Immunohistochemistry;

Underbody Blast Models of TBI Caused by Hyper-Acceleration and Secondary Head Impact

DTIC Science & Technology

2014-02-01

Cleveland RO, Tanzi RE, Stanton PK, McKee AC. (2012) Chronic traumatic encephalopathy in blast-exposed military veterans and a blast neurotrauma mouse model...exposure, remove brains, and process for electron microscopic analysis of cyto- and axonal ultrastructure and for histochemical evidence of acute ...of Trauma and Acute Care Surgery (see Appendix). These observations include increased axonopathy (silver staining) in the cerebellum and astrocyte

Combined Cytological and Transcriptomic Analysis Reveals a Nitric Oxide Signaling Pathway Involved in Cold-Inhibited Camellia sinensis Pollen Tube Growth

PubMed Central

Wang, Weidong; Sheng, Xianyong; Shu, Zaifa; Li, Dongqin; Pan, Junting; Ye, Xiaoli; Chang, Pinpin; Li, Xinghui; Wang, Yuhua

2016-01-01

Nitric oxide (NO) as a signaling molecule plays crucial roles in many abiotic stresses in plant development processes, including pollen tube growth. Here, the signaling networks dominated by NO during cold stress that inhibited Camellia sinensis pollen tube growth are investigated in vitro. Cytological analysis show that cold-induced NO is involved in the inhibition of pollen tube growth along with disruption of the cytoplasmic Ca2+ gradient, increase in ROS content, acidification of cytoplasmic pH and abnormalities in organelle ultrastructure and cell wall component distribution in the pollen tube tip. Furthermore, differentially expressed genes (DEGs)-related to signaling pathway, such as NO synthesis, cGMP, Ca2+, ROS, pH, actin, cell wall, and MAPK cascade signal pathways, are identified and quantified using transcriptomic analyses and qRT-PCR, which indicate a potential molecular mechanism for the above cytological results. Taken together, these findings suggest that a complex signaling network dominated by NO, including Ca2+, ROS, pH, RACs signaling and the crosstalk among them, is stimulated in the C. sinensis pollen tube in response to cold stress, which further causes secondary and tertiary alterations, such as ultrastructural abnormalities in organelles and cell wall construction, ultimately resulting in perturbed pollen tube extension. PMID:27148289

Ultrastructural and biomolecular detection of Rickettsiales-like organisms in tissues of rainbow trout with Red Mark Syndrome.

PubMed

Galeotti, M; Manzano, M; Beraldo, P; Bulfon, C; Rossi, G; Volpatti, D; Magi, G E

2017-07-01

Red mark syndrome (RMS) and US strawberry disease (US SD) are skin disorders affecting rainbow trout farmed in Europe and USA. The disease etiology has not yet been established. In spite of specific investigations, identifying Rickettsia-like organism (RLO)- and Midichloria-like organism (MLO)-related DNA in affected individuals, these pathogens have never been observed. We performed histological, ultrastructural and biomolecular analysis on skin and spleen samples of trout with RMS. Examination by TEM revealed the presence of intracytoplasmic microorganisms resembling Rickettsiales within macrophages, fibroblasts and erythrocytes. The microorganisms were oval or short rod shaped (400-800 nm in length and 100-200 nm in width) and often showed a cell wall similar to Gram-negative bacteria. PCR analysis for Rickettsiales supported these findings: 53% of affected trout were positive by both PCR and TEM The primers RiFCfw-RiFCrev were used to anneal both the RLO 16S DNA sequence and the MLO 16S DNA sequence. For this reason, and in agreement with previous studies confirming the presence of Rickettsiales-related DNA in trout with RMS, we assume that TEM detected microorganisms morphologically consistent with bacteria belonging to Rickettsiales order and could be considered as possible causative agents of RMS. © 2016 John Wiley & Sons Ltd.

Activation of cellular apoptosis in the caecal epithelium is associated with increased oxidative reactions in lactating goats after feeding a high-concentrate diet.

PubMed

Tao, Shiyu; Tian, Jing; Cong, Rihua; Sun, Lili; Duanmu, Yongqian; Dong, Haibo; Ni, Yingdong; Zhao, Ruqian

2015-03-01

What is the central question of this study? What are the ultrastructural changes of the caecal mucosa and the status of epithelial cellular apoptosis and oxidative reactions in lactating goats after prolonged feeding with a high-concentrate diet? What is the main finding and its importance? High-concentrate diet results in ultrastructural damage to the caprine caecal epithelium. Increased oxidative and decreased antioxidative reactions are involved in the process of activating epithelial apoptosis in the caecal epithelium of goats fed a high-concentrate diet. Our results provide new insight into the relationship between abnormal fermentation in the hindgut and damage to the intestinal mucosal barrier. The effect of feeding a high-concentrate diet (HC) to lactating ruminants on their hindgut epithelial structure remains unknown. In this study, 12 lactating goats were randomly assigned to either HC (65% of dry matter as concentrate; n = 6) or a low-concentrate diet (LC; 35% of dry matter as concentrate; n = 6). After 10 weeks, the epithelial ultrastructure and cell apoptotic status in the caecal mucosa were determined by transmission electron microscopy and TUNEL, respectively. The results showed that the level of free lipopolysaccharide (P < 0.05), total volatile fatty acid concentrations (P < 0.1) and starch content (P < 0.05) in the caecal digesta were significantly increased in HC- compared with LC-fed goats. The HC-fed goats exhibited obvious epithelial cellular damage, with widened tight junction spaces, nuclear breakdown and mitochondrial swelling. Compared with their LC-fed counterparts, HC-fed goats showed greater apoptosis in the caecal epithelium, as evidenced by more TUNEL-positive apoptotic cells. Western blot analysis showed that there was no significant difference in activated caspase-3, Bax protein expression in caecal epithelial mucosa between HC- and LC-fed goats (P > 0.05). However, the level of malondialdehyde content in the caecal epithelium from HC-fed goats was markedly higher than that in LC-fed goats (P < 0.05), whereas the level of glutathione peroxidase and the superoxide dismutase activity were significantly decreased. Gene expressions of cytokines, including interleukin-1β, interleukin-6, interleukin-10, tumour necrosis factor-α and interferon-γ, as well as myeloperoxidase activity in the caecal mucosa did not show any significant difference between HC- and LC-fed goats. These results indicate that feeding a high-concentrate diet to lactating goats for a prolonged period results in abnormal fermentation and structural disruption in the hindgut, which is accompanied by greater cellular apoptosis and an enhanced oxidative stress response. © 2015 The Authors. Experimental Physiology © 2015 The Physiological Society.