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.

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.

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 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)

Fine structures of embryonic discs of in vivo post-hatching porcine blastocysts at the pre-primitive streak stage.

PubMed

Xia, P; Liu, Z; Qin, P

2011-04-01

To date, reports about the ultrastructure of porcine embryonic discs have not shown details of the primitive streak. The main objective of this study was to examine the ultrastructure of interior and exterior embryonic discs in porcine in vivo blastocysts with diameters of 1, 3 and 9 mm using scanning electron microscopy and transmission electron microscopy. For the first time, we revealed the ultrastructure of the unusual group of cells in the pre-primitive streak area of embryonic discs. The cells were 1-2 μm in diameter, had high electron density and contained abundant, free ribosomes and endoplasmic reticulum. These primitive streak cells could represent original embryonic stem cells or represent a stem cell niche. The results also showed three types of cells on the exterior surface of the embryonic discs. Moreover, our results provided morphological evidence of condensed nuclei in the smooth cells on the surface of the embryonic disc. © 2010 Blackwell Verlag GmbH.

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.

Ultrastructural features of the osteoclasts from Paget's disease of bone in relation to a viral aetiology.

PubMed Central

Harvey, L; Gray, T; Beneton, M N; Douglas, D L; Kanis, J A; Russell, R G

1982-01-01

The ultrastructure of the osteocytes, osteoblasts, osteoclasts, haemopoietic and other connective tissue cells was examined in 27 biopsies from 22 patients with Paget's disease of bone. Electron microscopy showed characteristic nuclear and cytoplasmic inclusions in the osteoclasts of all of the 25 biopsies exhibiting histological evidence of Paget's disease. Such inclusions were absent from all the other types examined. The intranuclear inclusions consisted of stacked rows or complex whorls of tubular filaments with an individual filament diameter of 12-15 nm, often arranged in a paracrystalline array. The frequency of occurrence of inclusions in the osteoclasts and their individual nuclei measured quantitatively in 18 of the biopsies was related to the histological severity of the disease process. The similarity of the observed inclusions to those of paramyxovirus inclusion bodies (particularly measles) support the hypothesis that Paget's disease is a slow virus infection. Images PMID:7096600

Pathology of experimental Ebola virus infection in African green monkeys. Involvement of fibroblastic reticular cells.

PubMed

Davis, K J; Anderson, A O; Geisbert, T W; Steele, K E; Geisbert, J B; Vogel, P; Connolly, B M; Huggins, J W; Jahrling, P B; Jaax, N K

1997-08-01

Ebola virus has been responsible for explosive lethal outbreaks of hemorrhagic fever in both humans and nonhuman primates. Previous studies showed a predilection of Ebola virus for cells of the mononuclear phagocyte system and endothelial cells. To examine the distribution of lesions and Ebola virus antigen in the tissues of six adult male African green monkeys (Cercopithecus aethiops) that died 6 to 7 days after intraperitoneal inoculation of Ebola-Zaire (Mayinga) virus. Tissues were examined histologically, immunohistochemically, and ultrastructurally. A major novel finding of this study was that fibroblastic reticular cells were immunohistochemically and ultrastructurally identified as targets of Ebola virus infection. The role of Ebola virus-infected fibroblastic reticular cells in the pathogenesis of Ebola hemorrhagic fever warrants further investigation. This is especially important because of recent observations indicating that fibroblastic reticular cells, along with the reticular fibers they produce, maximize the efficiency of the immune response.

Recurrent uveitis in horses: vitreal examinations with ultrastructural detection of leptospires.

PubMed

Brandes, K; Wollanke, B; Niedermaier, G; Brem, S; Gerhards, H

2007-06-01

This study documents the examination of 17 horses (both sexes, 3-18 years old) suffering from spontaneous equine recurrent uveitis (ERU). Vitreal samples obtained by pars plana vitrectomy were examined macroscopically and ultrastructurally, and in most cases also by cultural examination, by microscopic agglutination test (MAT) and by polymerase chain reaction. In 24% (4/17) of the animals, ultrastructural examination by electron microscopy revealed intact leptospiral bacteria in the vitreous. The leptospires were detected freely in the vitreous and also incorporated by a phagocyte. They were surrounded by a rim of proteinaceous material which was reduced around a phagocytosed leptospira. Ninety-four per cent (16/17) of the vitreal samples presented significant antibody levels in the MAT, mostly against leptospiral serovar Grippotyphosa. Seventy-five per cent (9/12) of bacterial culture examinations were positive for leptospira. Polymerase chain reaction was positive in all (16/16) examinations performed. Our findings support previous reports suggesting that leptospires play an important role in the pathogenesis of ERU. Interestingly, this study found leptospires after secondary and later acute episodes. A persistent leptospiral infection is therefore suggested as the cause of ERU.

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.

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.

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.

[Kindler syndrome: clinical and ultra-structural particularities, a propos of three cases].

PubMed

El Fekih, Nadia; Mahfoudh, Anis; Zekri, Samy; Kharfi, Monia; Fazaa, Bécima; Jaafoura, Mohamed Habib; Kamoun, Mohamed Ridha

2011-08-01

Kindler's syndrome is a rare type of genetic skin condition belonging to the class of bullous poikilodermia. We report three new sibling cases of this rare syndrome. The condition was seen in three sisters aged 12, 16 and 20 years, born of a first-degree consanguineous marriage with no family history of Kindler's syndrome. The three patients presented spontaneously regressive bullous eruptions, poikilodermia of gradual onset, major cutaneous atrophy on the back of the hands and the feet, photosensitivity and gingival hypertrophy. Electron microscopy examination of poikilodermic skin showed normal anchoring filaments and intraepidermal cleavage. Diagnosis of Kindler's syndrome is based upon clinical evidence. Kidler's syndrome is a well defined clinical entity. Ultra-structural studies show intraepidermal, junctional, and dermal cleavage. This syndrome must be differentiated from congenital epidermolysis bullosa, Weary's syndrome, and other bullous hereditary poikilodermas. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Cadmium induces histopathological injuries and ultrastructural changes in the liver of freshwater turtle (Chinemys reevesii).

PubMed

Huo, Junfeng; Dong, Aiguo; Wang, Yonghui; Lee, Shaochin; Ma, Cungen; Wang, Lan

2017-11-01

The study investigated the histopathological and ultrastructural lesions of liver of freshwater turtle Chinemys reevesii exposed to Cadmium (Cd). The animals were exposed to 0 mg kg -1 (0.85% normal saline (NS)), 7.5 mg kg -1 , 15 mg kg -1 , 30 mg kg -1 Cd chloride separately by intraperitoneal injection. Liver samples were collected for examination of lesions under light and electronic microscopes. Results showed that liver tissues from Cd -treated animals presented various degrees of histopathological lesions. Liver cells showed swollen, degeneration and necrosis with dose-dependent manner. Under electronic microscope, nucleus, mitochondria and rough endoplasmic reticulum presented various degrees of lesions with dose-dependent manner. In conclusion, Cd has significant toxicity on liver tissue of the freshwater turtle, which occurs in a dose-dependent manner. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

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

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 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

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.

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

PubMed

Chwil, Mirosława; Chwil, Stanisław

2012-10-01

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

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.

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.

Ultrastructural preservation of tissues and their reaction to the infection with trichinella in the El Plomo mummy: Muscle fiber ultrastructure and trichinosis/mummy of the Cerro El Plomo.

PubMed

Héctor, Rodríguez; Omar, Espinoza-Navarro; González, Mercedes; Mario, Castro

2017-08-01

The El Plomo mummy was a pre-Columbian Incan child who was found mummified in the Andes Mountains above an altitude of 17,700 feet. In the environment, natural mummification occurred due to low temperatures and strong winds. Dating measurements (relative dating) by experts from the National Museum of Natural History of Chile established that the mummified body corresponds the Inca period (1,450 to 1,500 AD). In 2003, the body was transferred to the University of Chile Medical School for exhaustive medical examination. Tissue samples from the right quadriceps muscle were extracted and fixed in glutaraldehyde and postfixed in osmium tetroxide to obtain ultrathin sections to be observed by transmission electron microscope. Images were recorded on photographic paper, digitalized and analyzed by experts on morphology. Results showed a preservation of cell boundaries in striated muscle cells, but specific subcellular organelles or contractile sarcomeric units (actin and myosin) were unable to be recognized. However, the classical ultrastructural morphology of the polypeptide collagen type I was preserved intact both in primary and secondary organization. Therefore, we concluded that the process of natural mummification by freezing and strong winds is capable of damaging the ultrastructure of muscle cells and preserving collagen type I intact. © 2017 Wiley Periodicals, Inc.

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.

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

PubMed

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

2017-03-01

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

Histopathology of Middle East respiratory syndrome coronovirus (MERS-CoV) infection - clinicopathological and ultrastructural study.

PubMed

Alsaad, Khaled O; Hajeer, Ali H; Al Balwi, Mohammed; Al Moaiqel, Mohammed; Al Oudah, Nourah; Al Ajlan, Abdulaziz; AlJohani, Sameera; Alsolamy, Sami; Gmati, Giamal E; Balkhy, Hanan; Al-Jahdali, Hamdan H; Baharoon, Salim A; Arabi, Yaseen M

2018-02-01

The pathogenesis, viral localization and histopathological features of Middle East respiratory syndrome - coronavirus (MERS-CoV) in humans are not described sufficiently. The aims of this study were to explore and define the spectrum of histological and ultrastructural pathological changes affecting various organs in a patient with MERS-CoV infection and represent a base of MERS-CoV histopathology. We analysed the post-mortem histopathological findings and investigated localisation of viral particles in the pulmonary and extrapulmonary tissue by transmission electron microscopic examination in a 33-year-old male patient of T cell lymphoma, who acquired MERS-CoV infection. Tissue needle biopsies were obtained from brain, heart, lung, liver, kidney and skeletal muscle. All samples were collected within 45 min from death to reduce tissue decomposition and artefact. Histopathological examination showed necrotising pneumonia, pulmonary diffuse alveolar damage, acute kidney injury, portal and lobular hepatitis and myositis with muscle atrophic changes. The brain and heart were histologically unremarkable. Ultrastructurally, viral particles were localised in the pneumocytes, pulmonary macrophages, renal proximal tubular epithelial cells and macrophages infiltrating the skeletal muscles. The results highlight the pulmonary and extrapulmonary pathological changes of MERS-CoV infection and provide the first evidence of the viral presence in human renal tissue, which suggests tissue trophism for MERS-CoV in kidney. © 2017 John Wiley & Sons Ltd.

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

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.

Familial atrophia maculosa varioliformis cutis: an ultrastructural study.

PubMed

Dall'Oglio, F; Nasca, M R; Taparelli, F; Bacchelli, B; Micali, G

2001-01-01

Atrophia maculosa varioliformis cutis is a rare and distinctive form of idiopathic facial macular noninflammatory atrophy that may rarely be observed in members of the same family. We describe two brothers, ages 14 and 16 years, with spontaneously appearing, asymptomatic, varioliform and linear atrophic lesions. Their past medical history was positive for varicella occurring in childhood without residual facial scarring. Routine laboratory investigations and screening for circulating autoantibodies were negative. Both patients were concordant for HLA A2 and DQ4.1. Routine and ultrastructural histologic examination of a punch biopsy specimen showed the presence of scarce, small, fragmented elastic fibers and compact collagen bundles associated with hypertrophic fibroblasts in the dermis. Our patients remained clinically stable, untreated, over a 2-year follow-up period. No long-term follow-up data have previously been reported.

Surface topography and ultrastructural changes of mucinous carcinoma breast cells.

PubMed

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

2007-01-01

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

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.

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.

Anatomy and ultrastructure alterations of Leucaena leucocephala (Lam.) inoculated with mycorrhizal fungi in response to arsenic-contaminated soil.

PubMed

Schneider, Jerusa; Labory, Claudia Regina Gontijo; Rangel, Wesley Melo; Alves, Eduardo; Guilherme, Luiz Roberto Guimarães

2013-11-15

Many studies demonstrate the potential application of arbuscular mycorrhizal fungi (AMF) for remediation purposes, but little is known on AMF potential to enhance plant tolerance to arsenic (As) and the mechanisms involved in this process. We carried anatomical and ultrastructural studies to examine this symbiotic association and the characteristics of shoots and roots of Leucaena leucocephala in As-amended soils (35 and 75 mg As dm(-3)). The experiment used 3 AMF isolates from uncontaminated soils: Acaulospora morrowiae, Glomus clarum, and Gigaspora albida; a mixed inoculum derived from combining these 3 isolates (named Mix AMF); and, 3 AMF isolates from As-contaminated areas: A. morrowiae, G. clarum and Paraglomus occultum. Phytotoxicity symptoms due to arsenic contamination appeared during plant growth, especially in treatments without AMF application. Inoculation with G. clarum and the mixture of species (A. morrowiae, G. albida, and G. clarum) resulted in better growth of L. leucocephala in soils with high As concentrations, as well as significant As removal from the soil, showing a potential for using AMF in phytoextraction. Light microscopy (LS), transmission (TEM) and scanning electron microscopies (SEM) studies showed the colonization of the AMF in plant tissues and damage in all treatments, with ultrastructural changes being observed in leaves and roots of L. leucocephala, especially with the addition of 75 mg dm(-3) of As. Copyright © 2012 Elsevier B.V. All rights reserved.

Blue nevi of the Müllerian tract: case series and review of the literature.

PubMed

Craddock, Kenneth J; Bandarchi, Bizhan; Khalifa, Mahmoud A

2007-10-01

Blue nevi are rare in the cervix and vagina. Melanocytes are not normally found in these sites and have been hypothesized to arise either from the Schwann cells of stromal nerves or from melanocytic precursors which have aberrantly migrated from the neural crest to rest in the Müllerian stroma. Because of their rarity (3 previous cases in the literature), vaginal blue nevi have not previously been studied with immunohistochemical and ultrastructural analysis. We describe 3 cases of blue nevus occurring in the Müllerian tract, 1 in the vagina and 2 in the endocervix. The vaginal lesion was seen during routine examination of a 40-year-old woman. The endocervical blue nevi were incidental findings in hysterectomies performed for leiomyomata and endometrial serous carcinoma in women aged 44 and 57 years, respectively. All 3 cases showed loose aggregates of cytologically benign, pigmented, dendritic spindle cells in the superficial stroma. They were immunoreactive for S100 and melan-A, but not HMB45. Ultrastructural analysis revealed numerous melanosomes, with no Schwannian features identified. Compared with the endocervical lesions, the vaginal nevus cells were more heavily pigmented, and on electron microscopy, a greater proportion of stage IV melanosomes were seen. We provide the first immunohistochemical and ultrastructural findings in a vaginal blue nevus, which confirm that it is of a similar nature to the endocervical blue nevi. Ultrastructurally, our results support a melanocytic rather than Schwannian origin for Müllerian blue nevi.

Melanosome metabolism in the retinal pigmented epithelium of the opossum.

PubMed

Herman, K G; Steinberg, R H

1982-01-01

Melanosomal metabolism, including both formation and degradation of melanosomes, was studied in the retinal pigmented epithelium (RPE) of the adult opossum. The majority of the observations were made on a transitional zone between the tapetal and non-tapetal RPE, the region where melanosome metabolism was at its highest level. Formation of melanosomes, demonstrated ultrastructurally by the presence of stage-II and -III premelanosomes, was also examined autoradiographically following the incorporation of the melanin precursor, dihydroxyphenylalanine. The autoradiographic evidence indicated that many newly formed melanosomes were rapidly incorporated into complexes. Ultrastructural observations suggested that melanosome complexes were formed by at least two methods, via the fusion of melanosomes with phagosomes derived from outer segments of photoreceptors, or by the sequestration of melanosomes by cisternae. A central finding of this study, supported by both ultrastructural and histochemical data, is that there are specialized cellular regions that vary in melanosomal formation and lysosomal activity. Stage-II premelanosomes were observed only in the basal parts of the RPE cells, whereas stage-III and -IV melanosomes were found primarily in the apical RPE. Both ultrastructural and cytochemical observations indicated that degradation of melanosomes occurs only in the basal RPE. These findings are interpreted in terms of the expression of both tapetal and nontapetal characteristics in transitional cells. Finally, this study illustrates the role of lysosomal enzymes in shaping the pattern of pigmentation, and shows that the association of lysosomal activity with melanosomes depends on the functional state of the melanosome.

Structure and Ultrastructure of the Endodermal Region of the Alimentary Tract in the Freshwater Shrimp Neocaridina heteropoda (Crustacea, Malacostraca)

PubMed Central

Sonakowska, Lidia; Włodarczyk, Agnieszka; Poprawa, Izabela; Binkowski, Marcin; Śróbka, Joanna; Kamińska, Karolina; Kszuk-Jendrysik, Michalina; Chajec, Łukasz; Zajusz, Bartłomiej; Rost-Roszkowska, Magdalena Maria

2015-01-01

The freshwater shrimp Neocaridina heteropoda (Crustacea, Malacostraca, Decapoda) originates from Asia and is one of the species that is widely available all over the world because it is the most popular shrimp that is bred in aquaria. The structure and the ultrastructure of the midgut have been described using X-ray microtomography, transmission electron microscopy, light and fluorescence microscopes. The endodermal region of the alimentary system in N. heteropoda consists of an intestine and a hepatopancreas. No differences were observed in the structure and ultrastructure of males and females of the shrimp that were examined. The intestine is a tube-shaped organ and the hepatopancreas is composed of two large diverticles that are divided into the blind-end tubules. Hepatopancreatic tubules have three distinct zones – proximal, medial and distal. Among the epithelial cells of the intestine, two types of cells were distinguished – D and E-cells, while three types of cells were observed in the epithelium of the hepatopancreas – F, B and E-cells. Our studies showed that the regionalization in the activity of cells occurs along the length of the hepatopancreatic tubules. The role and ultrastructure of all types of epithelial cells are discussed, with the special emphasis on the function of the E-cells, which are the midgut regenerative cells. Additionally, we present the first report on the existence of an intercellular junction that is connected with the E-cells of Crustacea. PMID:25996951

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.

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.

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.

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.

The ultrastructural features of the premalignant oral lesions.

PubMed

Olinici, Doiniţa; Cotrutz, Carmen Elena; Mihali, Ciprian Valentin; Grecu, Vasile Bogdan; Botez, Emanuela Ana; Stoica, Laura; Onofrei, Pavel; Condurache, Oana; Dimitriu, Daniela Cristina

2018-01-01

Premalignant oral lesions are among the most important risk factors for the development of oral squamocellular carcinoma. Recent population studies indicate a significant rise in the prevalence of leukoplakia, erythroplakia/erythroleukoplakia, actinic cheilitis, submucous fibrosis and erosive lichen planus. Since standard histopathological examination has numerous limitations regarding the accurate appreciation of potential malignant transformation, the present study aims to aid these evaluations using the transmission electron microscopy (TEM) technique, which emphasizes ultrastructural changes pertaining to this pathology. Oral mucosa fragments collected from 43 patients that were clinically and histopathologically diagnosed with leukoplakia, erosive actinic cheilitis and erosive lichen planus have been processed through the classic technique for the examination using TEM and were examined using a Philips CM100 transmission electron microscope. The electron microscopy study has confirmed the histopathological diagnosis of the tissue samples examined using photonic microscopy and has furthermore revealed a series of ultrastructural details that on the one hand indicate the tendency for malignant transformation, and on the other reveal characteristic features of tumor development. All the details furnished by TEM complete the overall picture of morphological changes, specific to these lesions, indicating the importance of using these techniques in establishing both a correct diagnosis and prognosis.

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

PubMed

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

2012-11-01

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

Histological and ultrastructural effect of an Nd:YAG pulsed laser beam on dental hard tissue and pulp

NASA Astrophysics Data System (ADS)

Vignato, Costantino; Vignato, Giuseppe; Nardelli, Antonella; Baldan, Arianna; Mason, Pier N.

1994-09-01

The purpose of this study was to determine histological and ultrastructural modifications produced by an Nd:YAG pulsed laser beam after an in vivo exposure of human molars. Using a Nd:YAG pulsed laser beam delivered by a 600 micrometers optical fiber and concurrent air and water cooling spray, 14 human third molars with artificial first class cavities were exposed at different power levels (6, 7, and 8 W). All the teeth were extracted at different time periods between 10 and 25 days and prepared for histological examination. The results of the histological examination showed no evidence of degeneration or necrosis of the pulpar tissue. Analysis of the dentinal surfaces after exposure demonstrated that the dentinal tubules are completely closed due to the melted dentin. In conclusion a Nd:YAG pulsed laser beam with an air and water cooling spray is safe for treatments of class I decay and no necrosis or degeneration of the pulp was found for laser powers of 6, 7, and 8 W.

ULTRASTRUCTURAL STUDIES OF VASOPRESSIN EFFECT ON ISOLATED PERFUSED RENAL COLLECTING TUBULES OF THE RABBIT

PubMed Central

Ganote, Charles E.; Grantham, Jared J.; Moses, Harold L.; Burg, Maurice B.; Orloff, Jack

1968-01-01

Isolated cortical collecting tubules from rabbit kidney were studied during perfusion with solutions made either isotonic or hypotonic to the external bathing medium. Examination of living tubules revealed a reversible increase in thickness of the cellular layer, prominence of lateral cell membranes, and formation of intracellular vacuoles during periods of vasopressin-induced osmotic water transport. Examination in the electron microscope revealed that vasopressin induced no changes in cell structure in collecting tubules in the absence of an osmotic difference and significant bulk water flow across the tubule wall. In contrast, tubules fixed during vasopressin-induced periods of high osmotic water transport showed prominent dilatation of lateral intercellular spaces, bulging of apical cell membranes into the tubular lumen, and formation of intracellular vacuoles. It is concluded that the ultrastructural changes are secondary to transepithelial bulk water flow and not to a direct effect of vasopressin on the cells, and that vasopressin induces osmotic flow by increasing water permeability of the luminal cell membrane. The lateral intercellular spaces may be part of the pathway for osmotically induced transepithelial bulk water flow. PMID:4867134

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.

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.

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.

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

Energy metabolism of spermatozoa of the sand dollar Clypeaster japonicus: the endogenous substrate and ultrastructural correlates.

PubMed

Mita, M; Yasumasu, I; Nakamura, M

1994-07-01

Energy metabolism in spermatozoa of the sand dollar-sea urchin Clypeaster japonicus was examined. The spermatozoa contained triglyceride and cholesterol ester besides several kinds of phospholipids and cholesterol. Glycogen and glucose were present at extremely low levels. Following incubation of spermatozoa in seawater, the triglyceride content decreased rapidly. Other lipids, however, remained at constant levels. High lipase activity was demonstrated in the spermatozoa. Also, [1-14C]oleic acid was oxidized to 14CO2. Ultrastructural study showed that lipid globules were present at the bottom of the midpiece. After incubation in seawater, morphological changes in the lipid globules were observed and vacuoles of various sizes appeared near the lipid globules. Thus, it is concluded that C. japonicus spermatozoa obtain energy through oxidation of fatty acid from triglyceride stored in the lipid globules at the midpieces.

[In vitro activity of matrine against Candida albicans biofilms].

PubMed

Wu, Lan; Zhou, Zeng-tong; Zhou, Yong-mei; Wang, Hai-yan; Shi, Lin-jun

2009-08-01

To establish a model of Candida albicans biofilms and to examine the effect of matrine on C.albicans biofilms and ultrastructure. C. albicans collection strain ATCC76615 was obtained and propagated. Biofilms were formed in 96-well microtiter plates. Antifungal susceptibility testing of C. albicans biofilms were assessed with the tetrazolium salt (XTT) reduction assay. Confocal laser scanning microscopy (CLSM) and dead/live fluorescent staining technique were combined to detect the effects of Matrine on preformed C. albican biofilms' composition and ultrastructure. Matrine was active against different growth stages (early,middle,mature) of biofilms; The bioactivity and drug-resistance of C. albican biofilm increased with culturing time. CLSM showed that C. albicans biofilms were inhibited and growth were predominantly composed of yeast cells and pseudohyphae. This study demonstrates that Matrine has potent activity against C.albicans biofilms in vitro and potential therapeutic implication for biofilm-associated candidal infections.

Ultrastructural visualisation of proteoglycans in early unmineralised dentine of rat tooth germs stained with cuprolinic blue.

PubMed Central

Tenorio, D; Reid, A R; Katchburian, E

1990-01-01

The ultrastructural distribution and localisation of proteoglycans (PGs) of early developing rat dentine were examined using cuprolinic blue in a critical electrolyte concentration procedure. Results show that the cuprolinic blue method produces images of higher morphological quality than other cationic dyes. PGs appeared as ribbon-like electron-opaque precipitates of various sizes, ranging between 1.4 and 0.2 microns in length, distributed throughout the matrix and in close association with well preserved matrix vesicles and collagen fibrils. Matrix vesicles revealed tightly packed PG filaments which appeared to be attached to their membrane. It is possible that the close association of PG filaments with matrix vesicles and collagen indicates that PGs are related to the process of mineralisation of dentine. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 PMID:2384338

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.

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

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.

Scanning electron microscopy of tinea nigra.

PubMed

Guarenti, Isabelle Maffei; Almeida, Hiram Larangeira de; Leitão, Aline Hatzenberger; Rocha, Nara Moreira; Silva, Ricardo Marques E

2014-01-01

Tinea nigra is a rare superficial mycosis caused by Hortaea werneckii. This infection presents as asymptomatic brown to black maculae mostly in palmo-plantar regions. We performed scanning electron microscopy of a superficial shaving of a tinea nigra lesion. The examination of the outer surface of the sample showed the epidermis with corneocytes and hyphae and elimination of fungal filaments. The inner surface of the sample showed important aggregation of hyphae among keratinocytes, which formed small fungal colonies. The ultrastructural findings correlated with those of dermoscopic examination - the small fungal aggregations may be the dark spicules seen on dermoscopy - and also allowed to document the mode of dissemination of tinea nigra, showing how hyphae are eliminated on the surface of the lesion.

Scanning electron microscopy of tinea nigra*

PubMed Central

Guarenti, Isabelle Maffei; de Almeida, Hiram Larangeira; Leitão, Aline Hatzenberger; Rocha, Nara Moreira; Silva, Ricardo Marques e

2014-01-01

Tinea nigra is a rare superficial mycosis caused by Hortaea werneckii. This infection presents as asymptomatic brown to black maculae mostly in palmo-plantar regions. We performed scanning electron microscopy of a superficial shaving of a tinea nigra lesion. The examination of the outer surface of the sample showed the epidermis with corneocytes and hyphae and elimination of fungal filaments. The inner surface of the sample showed important aggregation of hyphae among keratinocytes, which formed small fungal colonies. The ultrastructural findings correlated with those of dermoscopic examination - the small fungal aggregations may be the dark spicules seen on dermoscopy - and also allowed to document the mode of dissemination of tinea nigra, showing how hyphae are eliminated on the surface of the lesion. PMID:24770516

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.

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.

Ultrastructure and wear patterns of the ventral epidermis of four snake species (Squamata, Serpentes).

PubMed

Klein, Marie-Christin G; Gorb, Stanislav N

2014-10-01

Snakes are limbless tetrapods highly specialized for sliding locomotion. This locomotion leads to the skin being exposed to friction loads, especially on the ventral body side, which leads to wear. It is presumed that snakes therefore have specific optimizations for minimizing abrasion. Scales from snakes with habitat, locomotor and/or behavior specializations have specific gradients in material properties that may be due to different epidermal architecture. To approach this issue we examined the skin of Lampropeltis getula californiae (terrestrial), Epicrates cenchria cenchria (generalist), Morelia viridis (arboreal), and Gongylophis colubrinus (burrowing) with a focus on (i) the ultrastructure of the ventral epidermis and (ii) the qualitative abrasion pattern of the ventral scales. Scanning and transmission electron microscopy revealed variations in the structure, thickness, layering, and material composition of the epidermis between the species. Furthermore, SEM and white light interferometer images of the scale surface showed that the abrasion patterns differed, even when the snakes were reared on the same substrate. These data support the idea that (i) a specific gradient in material properties may be due to a variation in epidermis architecture (thickness/ultrastructure) and (ii) this variation may be an optimization of material properties for specific ways of life. Copyright © 2014 Elsevier GmbH. All rights reserved.

Natural history of experimental intestinal atresia: morphologic and ultrastructural study.

PubMed

Baglaj, S M; Czernik, J; Kuryszko, J; Kuropka, P

2001-09-01

The aim of this study was to evaluate a natural history of congenital intestinal atresia (IA) in the chick embryo and to assess the type and nature of changes in the intestine at various developmental stages. Chick embryos underwent operative induction of IA on the 12th day of incubation. The procedure consisted of electrocoagulation of the mesenteric vessels supplying a 7- to 8-mm intestinal segment. The embryos were subjected to macroscopic examination, histologic and ultrastructural studies of the preatretic and postatretic bowel using the light microscope, scanning, and transmission electron microscopes. All investigations were performed in an experimental group (operated embryos), in a control group, and in a sham-operated group on the 15th, 17th, 19th, and 21st day of incubation. The original technique of an iatrogenic "vascular event" proved to be effective because IA developed in 96% of embryos surviving the procedure. The affected portion of the bowel underwent progressive necrosis, and signs of bowel obstruction could be observed 48 hours after operation. Cord atresia (type II) developed in 81% of embryos. Histologic investigations showed progressive thinning of mucosa, flattening of mucosal folds, and epithelial detachment within the intestine proximal to atresia. There was only mild hypertrophy of the muscular layers. All these pathomorphologic changes were of rapidly progressive nature until the 17th day of incubation. Later, the rate of distension of preatretic bowel and histologic changes were less. Ultrastructural investigation of the proximal bowel showed progressive flattening of the enterocytes associated with their apical bulging, widening of the intercellular spaces, and microvilli atrophy. Surprisingly, at days 19 and 21 of incubation, signs of induction of adaptive mechanisms with partial restoration of near-normal microvilli pattern were observed. Study of natural history of experimental IA indicates that histologic and ultrastructural lesions of the bowel are of dynamic nature and are not only the effect of pathologic intraluminal pressure. Copyright 2001 by W.B. Saunders Company.

Ultrastructure of spermatozoa of Onthophagus taurus (Coleoptera, Scarabaeidae) exhibits heritable variation

NASA Astrophysics Data System (ADS)

Werner, Michael; Simmons, Leigh W.

2011-03-01

Sperm competition is thought to be an important selective pressure shaping sperm form and function. However, few studies have moved beyond gross examinations of sperm morphology. Sperm length is subject to sexual selection via sperm competition in the scarab beetle Onthophagus taurus. Here, the structure and ultrastructure of spermatozoa in this species were investigated using light and electron microscopy. Spermatozoa were found to be filiform, measuring about 1,200 mm in length. The sperm head consists of a three-layered acrosome and a nuclear region bearing the anterior extension of the centriole adjunct. Acrosome and nuclear regions are bilaterally symmetric, with their axes of symmetry being orthogonal to each other. Head and flagellar structures are connected by a well-developed centriole adjunct. The sperm heads are asymmetrically surrounded by accessory material and embedded into the cytoplasm of the spermatocyst cell. The accessory material is produced inside the spermatids and then transferred to the outside due to a new membrane formed around the sperm's organelles. The old spermatid membrane separates the accessory material from the cyst cell. The flagellum contains a 9+9+2 axoneme, two accessory bodies, and two mitochondrial derivatives of unequal size. The major mitochondrial derivative is significantly larger than the minor one. The axoneme is arranged in a sinusoidal manner parallel along the major mitochondrial derivative. The spermatozoa show no progressive motility when released in buffer solution which is likely to be the result of the flagellar arrangement and the structure of the major mitochondrial derivative. The cross-sectional area of the minor and the major mitochondrial derivatives show different patterns of genetic variation. The data provide the first estimates of genetic variation in sperm ultrastructure for any species, and give evidence for the persistence of genetic variation in ultrastructure required for the rapid and divergent evolution that characterizes spermatozoa generally.

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

Elucidation of the mechanism of atorvastatin-induced myopathy in a rat model.

PubMed

El-Ganainy, Samar O; El-Mallah, Ahmed; Abdallah, Dina; Khattab, Mahmoud M; Mohy El-Din, Mahmoud M; El-Khatib, Aiman S

2016-06-01

Myopathy is among the well documented and the most disturbing adverse effects of statins. The underlying mechanism is still unknown. Mitochondrial dysfunction related to coenzyme Q10 decline is one of the proposed theories. The present study aimed to investigate the mechanism of atorvastatin-induced myopathy in rats. In addition, the mechanism of the coenzyme Q10 protection was investigated with special focus of mitochondrial alterations. Sprague-Dawely rats were treated orally either with atorvastatin (100mg/kg) or atorvastatin and coenzyme Q10 (100mg/kg). Myopathy was assessed by measuring serum creatine kinase (CK) and myoglobin levels together with examination of necrosis in type IIB fiber muscles. Mitochondrial dysfunction was evaluated by measuring muscle lactate/pyruvate ratio, ATP level, pAkt as well as mitochondrial ultrastructure examination. Atorvastatin treatment resulted in a rise in both CK (2X) and myoglobin (6X) level with graded degrees of muscle necrosis. Biochemical determinations showed prominent increase in lactate/pyruvate ratio and a decline in both ATP (>80%) and pAkt (>50%) levels. Ultrastructure examination showed mitochondrial swelling with disrupted organelle membrane. Co-treatment with coenzyme Q10 induced reduction in muscle necrosis as well as in CK and myoglobin levels. In addition, coenzyme Q10 improved all mitochondrial dysfunction parameters including mitochondrial swelling and disruption. These results presented a model for atorvastatin-induced myopathy in rats and proved that mitochondrial dysfunction is the main contributor in statin-myopathy pathophysiology. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

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

Growth inhibition and possible mechanism of oleamide against the toxin-producing cyanobacterium Microcystis aeruginosa NIES-843.

PubMed

Shao, Jihai; He, Yaxian; Li, Fan; Zhang, Huiling; Chen, Anwei; Luo, Si; Gu, Ji-Dong

2016-01-01

Oleamide, a fatty acid derivative, shows inhibitory effect against the bloom-forming cyanobacterium Microcystis aeruginosa. The EC50 of oleamide on the growth of M. aeruginosa NIES-843 was 8.60 ± 1.20 mg/L. In order to elucidate the possible mechanism of toxicity of oleamide against M. aeruginosa, chlorophyll fluorescence transient, cellular ultrastructure, fatty acids composition and the transcription of the mcyB gene involved in microcystins synthesis were studied. The results of chlorophyll fluorescence transient showed that oleamide could destruct the electron accepting side of the photosystem II of M. aeruginosa NIES-843. Cellular ultrastructure examination indicated that the destruction of fatty acid constituents, the distortion of thylakoid membrane and the loss of integrity of cell membrane were associated with oleamide treatment and concentration. The damage of cellular membrane increased the release of microcystins from intact cells into the medium. Results presented in this study provide new information on the possible mechanisms involved and potential utilization of oleamide as an algicide in cyanobacterial bloom control.

Effects of ionizing radiation on the enzyme activities and ultrastructural changes of poultry

NASA Astrophysics Data System (ADS)

Hwang, H.-I.; Hau, L.-B.

1995-02-01

Enzyme-catalyzed changes are generally recognized as one of the major reasons for fresh meat deterioration after irradiation. In this study, the effects of ionizing radiation and storage on the enzyme activities of poultry as well as the ultrastructural change of muscle were evaluated. When chicken breasts were irradiated at 4°C and -20°C, both Ca 2+-dependent protease and cathepsin D showed some degree of resistance to irradiation. The activities of those two enzymes decreased with the increase of irradiation doses. During storage, Ca 2+-dependent proteases showed a marked decrease in activity. On the other hand, the cathepsin D activity was not significantly changed at either 4°C or -20°C after 20 days. Transmission electron microscope examination showed no structural changes of the myofibrils with a radiation dose of up to 10 kGy at either 4°C or -20°C. Freezing protected the irradiated chicken breasts from autolytic enzymes damage during storage. In contrast, considerable sarcomere degradation occurred in Z-line for irradiated samples when stored at 4°C for 20 days. The action of the proteolytic enzymes may have been responsible for the sarcomere degradation in irradiated chicken breasts.

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.

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

Ultrastructural networks in growth cones and neurites of cultured central nervous system neurons.

PubMed

Tsui, H C; Ris, H; Klein, W L

1983-09-01

We have examined growth cones and neurites of cultured central nervous system neurons by high-voltage electron microscopy. Embryonic chicken retina cells were cultured on polylysine-treated and Formvar-coated gold grids for 2-6 days, fixed, and critical point dried. Growth cones and neurites were examined as unembedded whole mounts. Three-dimensional images from stereo-pair electron micrographs of these regions showed a high degree of ultrastructural articulation, with distinct, non-tapering filaments (5-9 nm in diameter) joining both cytoskeletal and membranous components. In the central regions of growth cones, interconnected structures included microtubules, large membranous sacs (up to 400 nm), and irregular vesicles (25-75 nm). A denser filamentous network was prevalent at the edges of growth cones. This network, which frequently adjoined the surface membrane, linked vesicles of uniform size (35-40 nm). Such vesicles often were seen densely packed in growth cone protrusions that were about the size of small synaptic boutons. Prevalent structural interconnections within growth cones conceivably could play a logistic role in specific membrane assembly, intracellular transport, endocytosis, and secretion. Because such processes are not unique to growth cones, the extensive linkages we have observed may have implications for cytoplasmic structure in general.

The effects of Euphorbia hirta on the ultrastructure of the murine liver, kidney and aorta

PubMed Central

WONG, J.Y.R.; CHEN, Y.S.; CHAKRAVARTHI, S.; JUDSON, J.P.; L., SANTHANA RAJ; ER, H.M.

2013-01-01

Euphorbia hirta is widely used in traditional remedies and has been used cross-culturally for generations against maladies such as asthma, skin ailments and hypertension. Previous studies have demonstrated that Euphorbia hirta has antibacterial activity, and have also indicated certain antimolluscidal, antimalarial and anti-inflammatory properties, the latter of which have been suggested to be more pronounced than those of the rheumatological drug, etanercept. To date, no studies have identified the anatomical effects of this herb on the organs of test animals. This study aimed to identify the effects of Euphorbia hirta on the ultrastructure of the murine liver, kidney and aorta. A total of 32 adult male Sprague-Dawley rats were divided into four groups; three groups were fed with aqueous extracts of Euphorbia hirta at doses of 1, 10 and 50 mg/kg, respectively, every alternate day for 50 days, while one group served as a control. The animals were later sacrificed and the liver, kidney and aorta harvested for examination by electron microscopy. The aorta showed no ultrastructural changes across the groups. Renal and hepatic tissue from the treated groups demonstrated dose-dependent injuries, which showed architectural damage beginning in the nuclei and spreading outwards. Taking into consideration the properties of Euphorbia hirta that have been described in previous studies, in addition to the results from the present study, it appears that the herb may exhibit similar effects to those of the quinolone group of antibiotics. Further in-depth investigations are required into the potential effects of Euphorbia hirta, deleterious and otherwise. PMID:24223653

Apoptosis of rat renal cells by organophosphate pesticide, quinalphos: Ultrastructural study.

PubMed

Eid, Refaat A

2017-01-01

Quinalphos or Ekalux, an organophosphate pesticide, is used in controlling the pests of a variety of crops. Quinalphos was studied on male Sprague-Dawley albino rats. The acute po LD50 of technical Ekalux was 19.95 mg/kg in males. Ekalux, produced several pathological changes in the kidney. A glomerulus demonstrated capillary lumina occluded by degenerated cellular debris. Basement membrane showed irregular wrinkling and branching. The proximal tubular cells showed damage such as dilation of endoplasmic reticulum, accumulation of glycogen granules, and pyknotic nucleus. The changes also included swelling of the mitochondria and reduction of the cristae up to total destruction. The distal tubular changes included electron lucency and vacuolation of cytoplasm. The distal convoluted tubule wall showed edematous epithelial cells, formation of blebs, and microvilli loss. These results suggest that subchronic exposure of rats to Ekalux causes ultrastructural changes in renal corpuscle and marked ultrastructural changes in proximal and distal tubules.

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 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.

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.

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.

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

PubMed

Gillett, Amber K; Ploeg, Richard; O'Donoghue, Peter J; Chapman, Phoebe A; Webb, Richard I; Flint, Mark; Mills, Paul C

2016-01-01

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

Henneguya melini n. sp. (Myxosporea: Myxobolidae), a parasite of Corydoras melini (Teleostei: Siluriformes) in the Amazon region: morphological and ultrastructural aspects.

PubMed

Mathews, Patrick D; Maia, Antônio A M; Adriano, Edson A

2016-09-01

A new species of myxozoan, Henneguya melini sp. n. (Myxosporea: Myxobolidae), was described based on morphologic and ultrastructural features. This is a parasite of the ornamental freshwater fish C. melini from the Rio Negro, and it was found in five of 30 (16.7 %) C. melini examined. The parasite was found in the gill filaments, and the plasmodia had form of round to ellipsoid, with mature and immature spores inside them. The average spore body was 15.5 ± 0.2 μm in length, 4.7 ± 0.1 μm in width, and the tail measured 25.3 ± 0.1 μm in length. The spores showed typical features of the genus Henneguya, with two valves of equal size and two symmetrical polar capsules of 4.8 ± 0.7 μm in length and 1.7 ± 0.3 μm in width. Each polar capsule had a polar filament with five to six turns. Based on morphology (morphologic and ultrastructural data) of the plasmodia and spores and the fact that this is the first report of a Henneguya species in a fish species of the genus Corydoras, it was considered a new myxozoan species.

Ultrastructural, protein and photosynthetic alterations induced by Pb and Cd in Cynara cardunculus L., and its potential for phytoremediation.

PubMed

Arena, C; Figlioli, F; Sorrentino, M C; Izzo, L G; Capozzi, F; Giordano, S; Spagnuolo, V

2017-11-01

The effects of cadmium and lead were investigated in Cynara cardunculus L. Plant uptake by root and shoot, changes in cell ultrastructure and photosynthetic efficiency, photosynthetic key protein levels, as well as regulation of stress-induced Hsp70 were examined. Cynara cardunculus accumulated Cd and Pb in their tissue, with a different trend for the two metals. The prompt translocation of Cd to the shoot may justify the ultrastructural injuries, especially observed in chloroplasts. However, Cd- treated plants did not show any decline in photochemistry; it is likely that Cd in shoot tissue triggers defense mechanisms, increasing the level of proteins involved in photosynthesis (i.e., Rubisco and D1 increased 7 and 4.5 fold respectively) as a compensatory response to neutralize chloroplast damage. The accumulation of Pb mainly in root, can explain the increase in Hsp70 level (23 folds) in this tissue. Pb reached the shoots, even at low amounts, causing an overall significant change in some photochemical parameters (QY and NPQ decreases and increases of 25%, respectively). The results suggest a higher sensitivity of C. cardunculus to Pb than Cd, although maximal photochemical efficiency suggests that this species seems to tolerate Pb and Cd and hence, it is a suitable candidate for phytoremediation. Copyright © 2017. Published by Elsevier Inc.

Copper microlocalisation and changes in leaf morphology, chloroplast ultrastructure and antioxidative response in white lupin and soybean grown in copper excess.

PubMed

Sánchez-Pardo, Beatriz; Fernández-Pascual, Mercedes; Zornoza, Pilar

2014-01-01

The microlocalisation of Cu was examined in the leaves of white lupin and soybean grown hydroponically in the presence of 1.6 (control) or 192 μM (excess) Cu, along with its effect on leaf morphology, (ultra)structure and the antioxidative response. The 192 μM dose led to a reduction in the total leaf area and leaf thickness in both species, although more strongly so in white lupin. In the latter species it was also associated with smaller spongy parenchyma cells, and smaller spaces between them, while in the soybean it more strongly reduced the size of the palisade parenchyma and epidermal cells. Energy-dispersive X-ray microanalysis showed that under Cu excess the metal was mainly localised inside the spongy parenchyma cells of the white lupin leaves, and in the lower epidermis cell walls in those of the soybean. Cu excess also promoted ultrastructural chloroplast alterations, reducing the photosynthetic capacity index and the green area of the leaves, especially in the soybean. Despite this, soybean appeared to be more tolerant to Cu excess than white lupin, because soybean displayed (1) lower accumulation of Cu in the leaves, (2) enhanced microlocalisation of Cu in the cell walls and (3) greater levels of induced total -SH content and superoxide dismutase and catalase activities that are expected for better antioxidative responses.

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

The Challenges of Diagnosing Primary Ciliary Dyskinesia

PubMed Central

O'Callaghan, Christopher; Knowles, Michael R.

2011-01-01

Primary ciliary dyskinesia (PCD) is a rare genetic disorder of ciliary structure and function. The diagnosis can be challenging, particularly when using nongenetic assays. The “gold standard” diagnostic test is ultrastructural analysis of respiratory cilia obtained by nasal scrape or brush biopsy. A few specialized centers use high-speed videomicroscopy to examine ciliary beat. Certain beat patterns correlate with ultrastructural defects, and, in some cases, subtle alterations in beat pattern can be seen when ultrastructure is normal. Recent studies have shown that nasal nitric oxide (NO) is very low in patients with PCD compared with healthy control subjects; therefore, this assay may be a useful screening or adjunctive test for PCD. Because acute respiratory illnesses may yield alterations in ciliary ultrastructure, ciliary beat, and nasal NO values, these tests should be performed during a stable baseline period. Identification of an array of PCD genes has provided the opportunity for making a definitive genetic diagnosis for PCD in some cases. All of these approaches have a role in diagnosing PCD. For example, PCD has been confirmed by identifying disease-causing mutations in a heavy dynein chain gene in individuals with normal ciliary ultrastructure but subtle defects in ciliary beat and low nasal NO. Priorities to improve nongenetic diagnostic capability include standardization of nasal NO as a screening test and the development of specialized centers using uniform approaches for the analysis of ciliary ultrastructure and ciliary beat pattern. Another chapter in this issue (see Zariwala and colleagues, pp. 430) addresses the progress toward improved capabilities for definitive genetic testing PMID:21926395

Phloem ultrastructure and pressure flow: Sieve-Element-Occlusion-Related agglomerations do not affect translocation.

PubMed

Froelich, Daniel R; Mullendore, Daniel L; Jensen, Kåre H; Ross-Elliott, Tim J; Anstead, James A; Thompson, Gary A; Pélissier, Hélène C; Knoblauch, Michael

2011-12-01

Since the first ultrastructural investigations of sieve tubes in the early 1960s, their structure has been a matter of debate. Because sieve tube structure defines frictional interactions in the tube system, the presence of P protein obstructions shown in many transmission electron micrographs led to a discussion about the mode of phloem transport. At present, it is generally agreed that P protein agglomerations are preparation artifacts due to injury, the lumen of sieve tubes is free of obstructions, and phloem flow is driven by an osmotically generated pressure differential according to Münch's classical hypothesis. Here, we show that the phloem contains a distinctive network of protein filaments. Stable transgenic lines expressing Arabidopsis thaliana Sieve-Element-Occlusion-Related1 (SEOR1)-yellow fluorescent protein fusions show that At SEOR1 meshworks at the margins and clots in the lumen are a general feature of living sieve tubes. Live imaging of phloem flow and flow velocity measurements in individual tubes indicate that At SEOR1 agglomerations do not markedly affect or alter flow. A transmission electron microscopy preparation protocol has been generated showing sieve tube ultrastructure of unprecedented quality. A reconstruction of sieve tube ultrastructure served as basis for tube resistance calculations. The impact of agglomerations on phloem flow is discussed.

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

PubMed Central

Froelich, Daniel R.; Mullendore, Daniel L.; Jensen, Kåre H.; Ross-Elliott, Tim J.; Anstead, James A.; Thompson, Gary A.; Pélissier, Hélène C.; Knoblauch, Michael

2011-01-01

Since the first ultrastructural investigations of sieve tubes in the early 1960s, their structure has been a matter of debate. Because sieve tube structure defines frictional interactions in the tube system, the presence of P protein obstructions shown in many transmission electron micrographs led to a discussion about the mode of phloem transport. At present, it is generally agreed that P protein agglomerations are preparation artifacts due to injury, the lumen of sieve tubes is free of obstructions, and phloem flow is driven by an osmotically generated pressure differential according to Münch’s classical hypothesis. Here, we show that the phloem contains a distinctive network of protein filaments. Stable transgenic lines expressing Arabidopsis thaliana Sieve-Element-Occlusion-Related1 (SEOR1)–yellow fluorescent protein fusions show that At SEOR1 meshworks at the margins and clots in the lumen are a general feature of living sieve tubes. Live imaging of phloem flow and flow velocity measurements in individual tubes indicate that At SEOR1 agglomerations do not markedly affect or alter flow. A transmission electron microscopy preparation protocol has been generated showing sieve tube ultrastructure of unprecedented quality. A reconstruction of sieve tube ultrastructure served as basis for tube resistance calculations. The impact of agglomerations on phloem flow is discussed. PMID:22198148

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.

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....

[An autopsy case of neonatal lactic acidosis].

PubMed

Giordano, G; Corradi, D; D'Adda, T; Melissari, M

2001-02-01

Defects in mitochondrial enzymes, such as pyruvate dehydrogenase and cytochrome oxidase, cause hereditary disorders which lead to modifications in cellular pH due to the accumulation of pyruvate and lactic acid. Mitochondrial diseases include severe neonatal diseases and less severe forms of adult diseases. We report the case of lactic acidosis in a newborn girl who was delivered at 36 weeks of gestation and who died 3 months after birth. Her family history revealed a relative with tetraparesis and mental retardation. Her clinical findings, such as tonic-clonic convulsions and accumulation of pyruvate and lactic acid in blood, urine and cerebrospinal fluid, were refractory to treatment and developed soon after birth. Ultrasound scans of the brain some days before death revealed cerebral atrophy with ventricular dilatation and thinning of the corpus callosum and septum pellucidum. The clinical diagnosis of metabolic lactic acidosis was confirmed by macroscopic, microscopic and ultrastructural findings seen at autopsy. On macroscopic examination, the heart was hypertrophic, and the brain was atrophic with ventricular dilatation and thinning of corpus callosum. Small cystic lesions were present in the basal ganglia. On microscopic examination, the latter were characterized by loss of neurons, gliosis and capillary proliferation. Ultrastructural examination of the heart and skeletal muscle showed lysis of myofibrils, mitochondrial pleomorphism and hyperplasia, and crystalline inclusion in mitochondria and in the matrix compartment. In reporting this case, we emphasize the importance of accurate postmortem examination and clinical data for the diagnosis of metabolic lactic acidosis.

The ultrastructure of rabbit sclera after scleral crosslinking with riboflavin and blue light of different intensities.

PubMed

Karl, Anett; Makarov, Felix N; Koch, Christian; Körber, Nicole; Schuldt, Carsten; Krüger, Martin; Reichenbach, Andreas; Wiedemann, Peter; Bringmann, Andreas; Iseli, Hans Peter; Francke, Mike

2016-08-01

We aimed to determine the ultrastructural changes of collagen fibrils and cells in the rabbit sclera after scleral crosslinking using riboflavin and blue light of different intensities. Scleral crosslinking is known to increase scleral stiffness and may inhibit the axial elongation of progressive myopic eyes. The equatorial parts of the sclera of one eye of six adult albino rabbits were treated with topical riboflavin solution (0.5 %) followed by irradiation with blue light (200, 400, 650 mW/cm(2)) for 20 min. After 3 weeks, the ultrastructure of scleral cells and the abundance of small- (10-100 nm) and large-diameter (>100 nm) collagen fibrils in fibril bundles of different scleral layers were examined with electron microscopy. In the scleral stroma of control eyes, the thickness of collagen fibrils showed a bimodal distribution. The abundance of small-diameter collagen fibrils decreased from the inner towards the outer sclera, while the amount of large-diameter fibrils and the scleral collagen content did not differ between different stroma layers. Treatment with riboflavin and blue light at 200 mW/cm(2) did not induce ultrastructural changes of cells and collagen fibrils in the scleral stroma. Treatment with blue light of higher intensities induced scleral cell activation in a scleral layer-dependent manner. In addition, outer scleral layers contained phagocytes that engulfed collagen fibrils and erythrocytes. Blue light of the highest intensity induced a reduction of the scleral collagen content, a decreased abundance of large-diameter collagen fibrils, and an increased amount of small-diameter fibrils in the whole scleral stroma. The data indicate that in rabbits, scleral crosslinking with riboflavin and blue light of 200 mW/cm(2) for 20 min is relatively safe and does not induce ultrastructural alterations of scleral cells and of the collagen composition of the scleral stroma. Irradiation with blue light of intensities between 200 and 400 mW/cm(2) induces scleral cell activation, which may contribute to scleral scarring and stiffening. Higher intensities cause scleritis.

Collagenous gastritis and collagenous colitis: a report with sequential histological and ultrastructural findings

PubMed Central

Pulimood, A; Ramakrishna, B; Mathan, M

1999-01-01

The case is reported of a young adult man with collagenous gastritis, an extremely rare disorder with only three case reports in the English literature, who subsequently presented with collagenous colitis. Sequential gastric biopsies showed a notable increase in thickness of the subepithelial collagen band. Ultrastructural study of gastric and rectal mucosa showed the characteristic subepithelial band composed of haphazardly arranged collagen fibres, prominent degranulating eosinophils, and activated pericryptal fibroblasts.


Keywords: collagenous gastritis; collagenous colitis; stomach; colon PMID:10323893

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.

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

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.

The role of immunohistochemistry, electron microscopy, and ultrastructural cytochemistry in the diagnosis of mixed carcinoma-neuroendocrine neoplasms.

PubMed

Graham, A R; Payne, C M; Nagle, R B; Angel, E

1987-02-01

We studied four mixed carcinoma-neuroendocrine neoplasms from gastrointestinal tract and pancreas by routine light microscopy (LM), immunohistochemistry (IH), electron microscopy (EM), and ultrastructural cytochemistry (UC). By LM, the individual tumors showed fairly pure neuroendocrine (carcinoid) or epithelial (papillary) patterns, mixed neuroendocrine-carcinoma features and poorly-differentiated tumor in sheets and nests which did not lend itself to morphologic characterization. IH demonstrated mixed expression, within different areas of the same neoplasm, of epithelial antigens (keratins and carcinoembryonic antigen [CEA]) and neuroendocrine markers (neuron-specific enolase [NSE], bombesin and neurohormonal peptides). By EM, each tumor showed ultrastructural features of epithelial and neuroendocrine differentiation which varied substantially in terms of number of cells involved and their distribution; two of the neoplasms showed biphasic differentiation within single cells. The nature of the neurosecretory granules was verified with the uranaffin reaction (UR). This study illustrates the value of combining LM, IH, EM and UC for the identification of mixed carcinoma-neuroendocrine lesions.

Influence of Environmental Changes on Physiology and Development of Polar Vascular Plants

NASA Astrophysics Data System (ADS)

Giełwanowska, Irena; Pastorczyk, Marta; Kellmann-Sopyła, Wioleta

2011-01-01

Polar vascular plants native to the Arctic and the Antarctic geobotanical zone have been growing and reproducing effectively under difficult environmental conditions, colonizing frozen ground areas formerly covered by ice. Our macroscopic observations and microscopic studies conducted by means of a light microscope (LM) and transmission electron microscope (TEM) concerning the anatomical and ultrastructural observations of vegetative and generative tissue in Cerastium arcticum, Colobanthus quitensis, Silene involucrata, plants from Caryophyllaceae and Deschampsia antarctica, Poa annua and Poa arctica, from Poaceae family. In the studies, special attention was paid to plants coming from diversity habitats where stress factors operated with clearly different intensity. In all examinations plants, differences in anatomy were considerable. In Deschampsia antarctica the adaxial epidermis of hairgrass leaves from a humid microhabitat, bulliform cells differentiated. Mesophyll was composed of cells of irregular shapes and resembled aerenchyma. The ultrastructural observations of mesophyll in all plants showed tight adherence of chloroplasts, mitochondria and peroxisomes, surface deformations of these organelles and formation of characteristic outgrowths and pocket concavities filled with cytoplasm with vesicles and organelles by chloroplasts. In reproduction biology of examined Caryophyllaceae and Poaceae plants growing in natural conditions, in the Arctic and in the Antarctic, and in a greenhouse in Olsztyn showed that this plant develops two types of bisexual flowers. Almost all ovules developed and formed seeds with a completely differentiated embryo both under natural conditions in the Arctic and the Antarctic and in a greenhouse in Olsztyn.

Influence of Environmental Changes on Physiology and Development of Polar Vascular Plants

NASA Astrophysics Data System (ADS)

Giełwanowska, Irena; Pastorczyk, Marta; Kellmann-Sopyła, Wioleta

2011-01-01

Polar vascular plants native to the Arctic and the Antarctic geobotanical zone have been growing and reproducing effectively under difficult environmental conditions, colonizing frozen ground areas formerly covered by ice. Our macroscopic observations and microscopic studies conducted by means of a light microscope (LM) and transmission electron microscope (TEM) concerning the anatomical and ultrastructural observations of vegetative and generative tissue in Cerastium arcticum, Colobanthus quitensis, Silene involucrata, plants from Caryophyllaceae and Deschampsia antarctica, Poa annua and Poa arctica, from Poaceae family. In the studies, special attention was paid to plants coming from diversity habitats where stress factors operated with clearly different intensity. In all examinations plants, differences in anatomy were considerable. In Deschampsia antarctica the adaxial epidermis of hairgrass leaves from a humid microhabitat, bulliform cells differentiated. Mesophyll was composed of cells of irregular shapes and resembled aerenchyma. The ultrastructural observations of mesophyll in all plants showed tight adherence of chloroplasts, mitochondria and peroxisomes, surface deformations of these organelles and formation of characteristic outgrowths and pocket concavities filled with cytoplasm with vesicles and organelles by chloroplasts. In reproduction biology of examined Caryophyllaceae and Poaceae plants growing in natural conditions, in the Arctic and in the Antarctic, and in a greenhouse in Olsztyn showed that this plant develops two types of bisexual flowers. Almost all ovules developed and formed seeds with a completely differentiated embryo both under natural conditions in the Arctic and the Antarctic and in a greenhouse in Olsztyn.

Renal pathophysiologic role of cortical tubular inclusion bodies.

PubMed

Radi, Zaher A; Stewart, Zachary S; Grzemski, Felicity A; Bobrowski, Walter F

2013-01-01

Renal tubular inclusion bodies are rarely associated with drug administration. The authors describe the finding of renal cortical tubular intranuclear and intracytoplasmic inclusion bodies associated with the oral administration of a norepinephrine/serotonin reuptake inhibitor (NSRI) test article in Sprague-Dawley (SD) rats. Rats were given an NSRI daily for 4 weeks, and kidney histopathologic, ultrastructural pathology, and immunohistochemical examinations were performed. Round eosinophilic intranuclear inclusion bodies were observed histologically in the tubular epithelial cells of the renal cortex in male and female SD rats given the NSRI compound. No evidence of degeneration or necrosis was noted in the inclusion-containing renal cells. By ultrastructural pathology, inclusion bodies consisted of finely granular, amorphous, and uniformly stained nonmembrane-bound material. By immunohistochemistry, inclusion bodies stained positive for d-amino acid oxidase (DAO) protein. In addition, similar inclusion bodies were noted in the cytoplasmic tubular epithelial compartment by ultrastructural and immunohistochemical examination.  This is the first description of these renal inclusion bodies after an NSRI test article administration in SD rats. Such drug-induced renal inclusion bodies are rat-specific, do not represent an expression of nephrotoxicity, represent altered metabolism of d-amino acids, and are not relevant to human safety risk assessment.

[Study on ultra-structural pathological changes of rats poisoned by tetramine].

PubMed

Zhi, Chuan-hong; Liu, Liang; Liu, Yan

2005-05-01

To observe ultra-structural pathological changes of materiality viscera of rats poisoned by different dose of tetramine and to study the toxic mechanism. Acute and subacute tetramine toxicity models were made by oral administration with different dose of tetramine. Brain, heart, liver, spleen and kidney were extracted and observed by electromicroscopic examination. The injuries of brain cells, cardiocytes and liver cells were induced by different dose of tetramine. These were not obviously different of the injuries of the kindy cells and spleen cells of rats poisoned by different dose of tetramine. Ultra-structural pathological changes were abserved including mitochondria slight swelling and neurolemma's array turbulence in the brain cells, mitochondria swelling or abolish and rupture of muscle fiber in the heart cells, mitochondria swelling and the glycogen decreased in the liver cells. The toxic target organs of tetramine are the heart, brain and liver.

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.

Ultrastructural networks in growth cones and neurites of cultured central nervous system neurons.

PubMed Central

Tsui, H C; Ris, H; Klein, W L

1983-01-01

We have examined growth cones and neurites of cultured central nervous system neurons by high-voltage electron microscopy. Embryonic chicken retina cells were cultured on polylysine-treated and Formvar-coated gold grids for 2-6 days, fixed, and critical point dried. Growth cones and neurites were examined as unembedded whole mounts. Three-dimensional images from stereo-pair electron micrographs of these regions showed a high degree of ultrastructural articulation, with distinct, non-tapering filaments (5-9 nm in diameter) joining both cytoskeletal and membranous components. In the central regions of growth cones, interconnected structures included microtubules, large membranous sacs (up to 400 nm), and irregular vesicles (25-75 nm). A denser filamentous network was prevalent at the edges of growth cones. This network, which frequently adjoined the surface membrane, linked vesicles of uniform size (35-40 nm). Such vesicles often were seen densely packed in growth cone protrusions that were about the size of small synaptic boutons. Prevalent structural interconnections within growth cones conceivably could play a logistic role in specific membrane assembly, intracellular transport, endocytosis, and secretion. Because such processes are not unique to growth cones, the extensive linkages we have observed may have implications for cytoplasmic structure in general. Images PMID:6577454

[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.

Numerous eosinophilic globules (skeinoid fibers) in a duodenal stromal tumor: an exceptional case showing smooth muscle differentiation.

PubMed

Matsukuma, S; Doi, M; Suzuki, M; Ikegawa, K; Sato, K; Kuwabara, N

1997-11-01

A unique case of duodenal stromal tumor in a 51-year-old man is reported. The tumor histologically showed spindle cell proliferation and numerous eosinophilic globules. Most globules were composed of tangled 45 nm thick fibrils, which were ultrastructurally identical to 'skeinoid fibers'. The presence of glycogen granules in the tumor cells and the immunoreactivity for alpha-smooth muscle actin suggested smooth muscle differentiation. Focal ultrastructural findings also supported the smooth muscle nature of this tumor. There were no immunohistochemical and ultrastructural features indicating neural differentiation. In previous studies, the presence of such 'skeinoid fibers' was suggested to be a histological marker for neural differentiation in gastrointestinal stromal tumor. However, the findings in the present case suggest that numerous 'skeinoid fibers' can be identified in duodenal stromal tumor with smooth muscle differentiation, although this condition may be rare.

[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.

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.

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

Jiang, Zhenzhou, E-mail: jiangcpu@yahoo.com.cn; Bao, Qingli, E-mail: bao_ql@126.com; Sun, Lixin, E-mail: slxcpu@126.com

This report describes an investigation of the pathological mechanism of acute renal failure caused by toxic tubular necrosis after treatment with aristolochic acid I (AAI) in Sprague–Dawley (SD) rats. The rats were gavaged with AAI at 0, 5, 20, or 80 mg/kg/day for 7 days. The pathologic examination of the kidneys showed severe acute tubular degenerative changes primarily affecting the proximal tubules. Supporting these results, we detected significantly increased concentrations of blood urea nitrogen (BUN) and creatinine (Cr) in the rats treated with AAI, indicating damage to the kidneys. Ultrastructural examination showed that proximal tubular mitochondria were extremely enlarged andmore » dysmorphic with loss and disorientation of their cristae. Mitochondrial function analysis revealed that the two indicators for mitochondrial energy metabolism, the respiratory control ratio (RCR) and ATP content, were reduced in a dose-dependent manner after AAI treatment. The RCR in the presence of substrates for complex I was reduced more significantly than in the presence of substrates for complex II. In additional experiments, the activity of respiratory complex I, which is partly encoded by mitochondrial DNA (mtDNA), was more significantly impaired than that of respiratory complex II, which is completely encoded by nuclear DNA (nDNA). A real-time PCR assay revealed a marked reduction of mtDNA in the kidneys treated with AAI. Taken together, these results suggested that mtDNA depletion and respiratory chain defects play critical roles in the pathogenesis of kidney injury induced by AAI, and that the same processes might contribute to aristolochic acid-induced nephrotoxicity in humans. -- Highlights: ► AAI-induced acute renal failure in rats and the proximal tubule was the target. ► Tubular mitochondria were morphologically aberrant in ultrastructural examination. ► AAI impair mitochondrial bioenergetic function and mtDNA replication.« less

Myxosporean plasmodial infection associated with ulcerative lesions in young-of-the-year Atlantic menhaden in a tributary of the Chesapeake Bay, and possible links to Kudoa clupeidae

USGS Publications Warehouse

Reimschuessel, R.; Gieseker, C.M.; Driscoll, C.; Baya, A.; Kane, A.S.; Blazer, V.S.; Evans, J.J.; Kent, M.L.; Moran, J.D.W.; Poynton, S.L.

2003-01-01

Ulcers in Atlantic menhaden Brevoortia tyrannus (Latrobe) (Clupeidae), observed along the USA east coast, have been attributed to diverse etiologies including bacterial, fungal and, recently, harmful algal blooms. To understand the early pathogenesis of these lesions, we examined juvenile Atlantic menhaden collected during their seasonal presence in Chesapeake Bay tributaries from April to October 1999 and from March to August 2000. We conducted histopathological examinations of young-of-the-year fish from the Pocomoke River tributary, which has a history of fish mortalities and high lesion prevalence. Kudoa clupeidae (Myxozoa: Myxosporea) spores were present in the muscles of fish collected in both years. Of the fish assessed by histology in April, 5 to 14% were infected, while in May 90 to 96% were infected. Infection rates remained high during the summer. Mature spores were primarily located within myomeres and caused little or no observable pathological changes. Ultrastructure showed spores with capsulogenic cells bearing filamentous projections, and a basal crescentic nucleus with mottled nucleoplasm containing cleaved, condensed chromatin. Also, a highly invasive plasmodial stage of a myxozoan was found in the lesions of juvenile Atlantic menhaden. The plasmodia were observed in fish collected between May and July, with the maximum occurrence in late June 1999 and late May 2000. Plasmodia penetrated and surrounded muscle bundles, causing grossly observable raised lesions in 73% of all fish infected with this invasive stage. Plasmodia were also detected in the visceral organs, branchial arches, and interocular muscles of some fish. Some of the invasive extrasporogonic plasmodial lesions were associated with ulcers and chronic inflammatory infiltrates. The plasmodial stage appeared to slough out of the tissue with subsequent evidence of wound healing. Ultrastructure showed plasmodia with an elaborate irregular surface, divided into distinct ectoplasm and endoplasm; the latter contained numerous spherical vegetative nuclei, secondary generative cells, and occasional cell doublets. Our ultrastructural studies indicate that the plasmodial organisms, which are important in the etiology of the skin lesions, are myxozoans, and they may represent early stages of K. clupeidae.

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)

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

[Comparative ultrastructural study of parotid gland, lacrimal gland and pituitary gland between miniature pig and mouse].

PubMed

Yan, Xing; Hai, Bo; Sun, Yi-lin; Zhang, Chun-mei; Wang, Song-ling

2009-02-01

To study the ultrastructure of parotid glands, lacrimal glands and pituitary glands between miniature pig and mouse. Five adult miniature pigs and 5 mice were studied. Ultrastructure of their parotid glands, lacrimal glands, and pituitary glands was observed. The secretary granules in acinar cell of miniature pig parotid glands showed higher density and more aequalis than those of mice. The cell apparatus in acinar cell of mouse parotid glands were more plentiful than those of miniature pigs. The secretary granules on blood vessel wall were richer in parotid gland of miniature pigs compared with mouse parotid gland. Lacrimal gland had the similar ultrastructure to parotid gland in these two animals. Many blood vessel antrum were found in pituitary glands of these two animals. Compared with mouse parotid glands, there are more secretary granules in acinar cells and vascular endothelial cells in miniature pig parotid glands, which might enter blood stream and have function of endocrine secretion.

Myelin basic protein-messenger RNA (MBP-mRNA) expression during triethyltin-induced myelin edema.

PubMed

Veronesi, B; Jones, K; Gupta, S; Pringle, J; Mezei, C

1991-01-01

Triethyltin (TET) is a neurotoxicant that produces severe but transient cerebral edema, characterized ultrastructurally by vacuolation of the intraperiod line of central nervous system (CNS) myelin. TET has been reported to depress levels of myelin basic protein (MBP), a protein thought to play a critical role in myelin compaction. In the present study, the genomic expression (i.e., mRNA) of MBP was monitored throughout the pathogenesis of TET-induced myelin edema and recovery in Sprague-Dawley rats given a single injection of a neuropathic (8.0 mg/kg) or non-neuropathic (0.8 mg/kg) dose of TET-bromide. Levels of MBP-mRNA from the anterior and posterior brain were collected 1 hr, 3 hr, 2d, and 7d, postexposure. The optic nerve and caudal brainstem, representing anterior and posterior brain sites, respectively, were examined at the same time-points for ultrastructural evidence of edema and recovery. Our data indicate that neuropathic doses (8.0 mg/kg) of TET significantly stimulated MBP transcript throughout the brain at all exposure time-points. The magnitude and time-course of this stimulation differed in the anterior and posterior brain, with the latter region showing higher levels of MBP-mRNA. In the posterior brain, the highest levels of mRNA correlated with the appearance of edema in the caudal brainstem. In the anterior brain, MBP-mRNA levels were only marginally increased over controls. Ultrastructural evidence of myelin edema was confined to the brainstem in rats treated with neuropathic dose of TET. Intralamellar vacuolation appeared at 3 hr and 2d postexposure and could be correlated with peak levels of MBP transcript, whereas, recompacted myelin, which appeared by 7d postexposure, was associated with declining levels of the mRNA. Ultrastructural changes in the oligodendroglia were suggestive of metabolic stimulation and correlated with high MBP-mRNA levels. In summary, these data indicate that an initial genomic event in TET-induced myelin edema is stimulation of MBP transcript.

Aluminium chloride impairs long-term memory and downregulates cAMP-PKA-CREB signalling in rats.

PubMed

Zhang, Lifeng; Jin, Cuihong; Lu, Xiaobo; Yang, Jinghua; Wu, Shengwen; Liu, Qiufang; Chen, Rong; Bai, Chunyu; Zhang, Di; Zheng, Linlin; Du, Yanqiu; Cai, Yuan

2014-09-02

Epidemiological investigations have indicated that aluminium (Al) is an important environmental neurotoxicant that may be involved in the aetiology of the cognitive dysfunction associated with neurodegenerative diseases. Additionally, exposure to Al is known to cause neurobehavioural abnormalities in animals. Previous studies demonstrated that Al impaired early-phase long-term potentiation (E-LTP) in vivo and in vitro. Our previous research revealed that Al could impair long-term memory via the impairment of late-phase long-term potentiation (L-LTP) in vivo. However, the exact mechanism by which Al impairs long-term memory has been poorly studied thus far. This study was designed not only to observe the effects of subchronic Al treatment on long-term memory and hippocampal ultrastructure but also to explore a possible underlying mechanism (involving the cAMP-PKA-CREB signalling pathway) in the hippocampus of rats.. Pregnant Wistar rats were assigned to four groups. Neonatal rats were exposed to Al by parental lactation for 3 weeks and then fed with distilled water containing 0, 0.2%, 0.4% or 0.6% Al chloride (AlCl3) for 3 postnatal months. The levels of Al in the blood and hippocampus were quantified by atomic absorption spectrophotometry. The shuttle-box test was performed to detect long-term memory. The hippocampus was collected for ultrastructure observation, and the level of cAMP-PKA-CREB signalling was examined. The results showed that the Al concentrations in the blood and hippocampus of Al-treated rats were higher than those of the control rats. Al may impair the long-term memory of rats. Hippocampal cAMP, cPKA, pCREB, BDNF and c-jun expression decreased significantly, and the neuronal and synaptic ultrastructure exhibited pathological changes after Al treatment. These results indicated that Al may induce long-term memory damage in rats by inhibiting cAMP-PKA-CREB signalling and altering the synaptic and neuronal ultrastructure in the hippocampus. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

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.

Characterization of amyloid in equine recurrent uveitis as AA amyloid.

PubMed

Ostevik, L; de Souza, G A; Wien, T N; Gunnes, G; Sørby, R

2014-01-01

Two horses with chronic uveitis and histological lesions consistent with equine recurrent uveitis (ERU) were examined. Microscopical findings in the ciliary body included deposits of amyloid lining the non-pigmented epithelium, intracytoplasmic, rod-shaped, eosinophilic inclusions and intraepithelial infiltration of T lymphocytes. Ultrastructural examination of the ciliary body of one horse confirmed the presence of abundant extracellular deposits of non-branching fibrils (9-11 nm in diameter) consistent with amyloid. Immunohistochemistry revealed strong positive labelling for AA amyloid and mass spectrometry showed the amyloid to consist primarily of serum amyloid A1 in both cases. The findings suggest that localized, intraocular AA amyloidosis may occur in horses with ERU. Copyright © 2014 Elsevier Ltd. All rights reserved.

Collagen Fibrils and Proteoglycans of Macular Dystrophy Cornea: Ultrastructure and 3D Transmission Electron Tomography.

PubMed

Akhtar, Saeed; Alkatan, Hind M; Kirat, Omar; Khan, Adnan A; Almubrad, Turki

2015-06-01

We report the ultrastructure and 3D transmission electron tomography of collagen fibrils (CFs), proteoglycans (PGs), and microfibrils within the CF of corneas of patients with macular corneal dystrophy (MCD). Three normal corneas and three MCD corneas from three Saudi patients (aged 25, 31, and 49 years, respectively) were used for this study. The corneas were processed for light and electron microscopy studies. 3D images were composed from a set of 120 ultrastructural images using the program "Composer" and visualized using the program "Visuliser Kai". 3D image analysis of MCD cornea showed a clear organization of PGs around the CF at very high magnification and degeneration of the microfibrils within the CF. Within the MCD cornea, the PG area in the anterior stroma was significantly larger than in the middle and posterior stroma. The PG area in the MCD cornea was significantly larger compared with the PG area in the normal cornea. The CF diameter and inter-fibrillar spacing of the MCD cornea were significantly smaller compared with those of the normal cornea. Ultrastructural 3D imaging showed that the production of unsulfated keratin sulfate (KS) may lead to the degeneration of micro-CFs within the CFs. The effect of the unsulfated KS was higher in the anterior stroma compared with the posterior stroma.

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

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.

Spontaneous rat nephroblastoma: ultrastructure of a transplant line.

PubMed

Hard, G C; Noble, R L

1982-08-01

Tumor tissue derived from a nephroblastoma arising spontaneously in an Nb hooded rat and carried for 56 generations as a subcutaneous syngeneic transplant was examined by electron microscopy. Histologically, the transplant showed the typical pattern of dense clusters or sheets of basophilic epithelioid cells set within ramifying tracts of fibrous mesenchyme. At the ultrastructural level, the tumor cells within dense clusters were arranged in anastomotic cords that circumscribed clear intervening spaces. The tumor cells were a monomorphic population possessing the morphologic characteristics of blast cells, including polyribosomes as the predominant cytoplasmic organelle. Furthermore, the close contiguity of cells within the cords, their polyhedral form, and their connection by intercellular junctions established the tumor cell type as epithelial. Consistent with benign stroma, mesenchymal tracts contained highly differentiated, mature fibroblasts, collagen, phagocytes, cells of the lymphoid series, and normal blood vessels. No transitional forms between epithelium and mesenchyme suggestive of bipotential differentiation were seen. Although the data represent only a single transplantation line, the observations support the contention (based on light microscopic appraisal of a number of primary tumors) that nephroblastoma in te rat can be a purely epithelial neoplasm.

Effects of CO2 Enrichment on Growth and Development of Impatiens hawkeri

PubMed Central

Zhang, Fan-Fan; Wang, Yan-Li; Huang, Zhi-Zhe; Zhu, Xiao-Chen; Zhang, Feng-Jiao; Chen, Fa-Di; Fang, Wei-Min; Teng, Nian-Jun

2012-01-01

The effects of CO2 enrichment on growth and development of Impatiens hawkeri, an important greenhouse flower, were investigated for the purpose of providing scientific basis for CO2 enrichment to this species in greenhouse. The plants were grown in CO2-controlled growth chambers with 380 (the control) and 760 (CO2 enrichment) μmol·mol−1, respectively. The changes in morphology, physiology, biochemistry, and leaf ultrastructure of Impatiens were examined. Results showed that CO2 enrichment increased flower number and relative leaf area compared with the control. In addition, CO2 enrichment significantly enhanced photosynthetic rate, contents of soluble sugars and starch, activities of peroxidase (POD), superoxide dismutase (SOD), and ascorbate peroxidase (APX), but reduced chlorophyll content and malondialdehyde (MDA) content. Furthermore, significant changes in chloroplast ultrastructure were observed at CO2 enrichment: an increased number of starch grains with an expanded size, and an increased ratio of stroma thylakoid to grana thylakoid. These results suggest that CO2 enrichment had positive effects on Impatiens, that is, it can improve the visual value, promote growth and development, and enhance antioxidant capacity. PMID:22536147

Ultrastructural and histochemical study on the interrenal cells of the male stickleback (Gasterosteus aculeatus, Teleostea), in relation to the reproductive annual cycle

PubMed Central

CIVININI, ANNALENA; PADULA, DANIELA; GALLO, VALENTINA P.

2001-01-01

The steroidogenic interrenal cells in the adrenal homologue of the male stickleback (Gasterosteus aculeatus) were studied in relation to the reproductive cycle by means of histological and ultrastructural observations, and using histochemical methods for the localisation of 3β-hydroxysteroid dehydrogenase (3βHSD) and 17β-hydroxysteroid dehydrogenase (17βHSD). To determine the various stages of the reproductive cycle, the testes were also examined by histological and histochemical methods (3βHSD). The results indicate that in this teleost the interrenal cells can undergo a cycle in which phases characterised by different cytological aspects are observed. During this cycle there is a renewal of organelles, in particular mitochondria and SER. Periodic degenerative processes are also found. Organelle cytology showed that the cell cycle has at least 3 different aspects during the year. An analogy with some cytological aspects of the adrenal zonation in mammals is possible. It is postulated that the interrenal gland activity could substitute or supplement androgen production by the testes. PMID:11554507

[Trichomycosis (trichobacteriosis) capitis in an infant: Microbiological, dermoscopic and ultrastructural features].

PubMed

Bonifaz, Alexandro; Ramírez-Ricarte, Ixchel; Rodríguez-Leviz, Alejandra; Hernández, Marco A; Mena, Carlos; Valencia, Adriana

2017-04-01

Trichomycosis is a superficial infection caused by Corynebacterium flavescens, which regularly affects axillary, and to a a lesser extent, pubic, scrotal and intergluteal, and exceptionally, head hairs or trichomycosis capitis (TC). This condition is characterised by the formation of bacterial nodules. Clinically, it can be confused with white piedra or pediculosis. The diagnosis is made by microscopic and dermoscopic observation and confirmed by culture. To present a case of TC in an infant and illustrate the microscopic, dermoscopic, and ultrastructural characteristics. A 6 month-old boy, otherwise healthy, with multiple yellowish concretions on the hairs of the head. TC was confirmed by yellow fluorescence with Wood’s light; white-yellowish beads, like “rosaries of crystalline stones’’ were observed on dermoscopy, direct examination showed bacterial masses, and Corynebacterium flavescens was identified by culture. A superficial infection, without perforation of the hairs, was confirmed by electron microscopy. Treatment with fusidic acid for 3 weeks achieved a clinical and microbiological cure. TC is a rare condition that affects children, and tends to be mistaken for other diseases of the hair, such as pediculosis and mycotic infections.

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

Destruction of maternal centrioles during fertilization of the brown alga, Scytosiphon lomentaria (Scytosiphonales, Phaeophyceae).

PubMed

Nagasato, Chikako; Motomura, Taizo

2004-10-01

In brown algal fertilization, a pair of centrioles is derived from the male gamete, irrespective of the sexual reproduction pattern, i.e., isogamy, anisogamy, or oogamy. In this study, the manner in which the maternal centriole structure is destroyed in early zygotes of the isogamous brown alga Scytosiphon lomentaria was examined by electron microscopy. At fertilization, the zygote had two pairs of centrioles (flagellar basal bodies) derived from motile male and female gametes, and there was no morphological difference between the two pairs. The flagellar basal plate and the axonemal microtubules were still connected with the distal end of centrioles. Ultrastructural observations showed that the integrity of maternal-derived centrioles began to degenerate even in the 1-h-old zygote. At that time, the cylinder of triplet microtubules of the maternal centrioles became shorter from the distal end, and a section passing through the centrioles indicated that a part of the nine triplets of microtubules changed into doublet or singlet microtubules by degeneration of B and/or C tubules. In 2-h-old zygote, there was no trace of maternal centrioles ultrastructurally, and only the paternal centrioles remained. Further, reduction of centrin accompanying destruction of the maternal centrioles was examined in immunofluorescence microscopy. Centrin localized at the paternal and the maternal centrioles had the same fluorescence intensity in the early zygotes. At 4-6 h after fertilization, two spots indicating centrin localization showed different fluorescence intensity. Later, the weaker spot disappeared completely. These results showed that there is a difference in time between the destruction of the centriolar cylinders and the reduction of centrin molecules around them. Copyright 2004 Wiley-Liss, Inc.

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

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.

[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.

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.

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.

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

PubMed Central

Gillett, Amber K.; Ploeg, Richard; O’Donoghue, Peter J.; Chapman, Phoebe A.; Webb, Richard I.; Flint, Mark; Mills, Paul C.

2016-01-01

Four sea snakes (two Hydrophis major, one Hydrophis platurus, one Hydrophis elegans) were found washed ashore on different beaches in the Sunshine Coast region and Fraser Island in Queensland, Australia between 2007–2013. Each snake had multiple granulomas and locally extensive regions of pallor evident in the hypaxial and intercostal musculature along the body. Lesions in two individuals were also associated with vertebral and rib fractures. Histological examination revealed granulomas scattered throughout skeletal muscle, subcutaneous adipose tissue and fractured bone. These were composed of dense aggregates of microsporidian spores surrounded by a mantle of macrophages. Sequences (ssrRNA) were obtained from lesions in three sea snakes and all revealed 99% similarity with Heterosporis anguillarum from the Japanese eel (Anguillarum japonica). However, ultrastructural characteristics of the organism were not consistent with those of previous descriptions. Electron microscopic examination of skeletal muscle revealed large cysts (not xenomas) bound by walls of fibrillar material (Heterosporis-like sporophorocyst walls were not detected). The cysts contained numerous mature microsporidian spores arranged in small clusters, sometimes apparently within sporophorous vesicles. The microspores were monomorphic, oval and measured 2.5–3.0 μm by 1.6–1.8 μm. They contained isofilar polar filaments with 11 (infrequently 9–12) coils arranged in two ranks. This is the first published report of a microsporidian infection in hydrophiid sea snakes. This discovery shows microsporidia with molecular affinities to Heterosporis anguillarum but ultrastructural characters most consistent with the genus Pleistophora (but no hitherto described species). Further studies are required to determine whether the microsporidian presented here belongs to the genus Heterosporis, or to a polymorphic species group as suggested by the recognition of a robust Pleistophora/Heterosporis clade by molecular studies. The gross and histological pathology associated with these infections are described. PMID:27007116

Ochronosis-like condition in a cat.

PubMed

Bryan, Laura K; Weeks, Brad R; Payne, Harold Ross; Thompson, Lori A; Mansell, Joanne L

2016-08-01

Endogenous ochronosis is caused by a defect in the enzyme homogentisate 1,2-dioxygenase (HGD), which results in abnormal pigment deposition in the skin and urine abnormalities. Ochronosis previously has not been described histologically or ultrastructurally in a domestic animal species. To describe the clinical, histopathological and ultrastructural findings in a case of aberrant pigmentation in a cat with features that resemble ochronosis. A 5-year-old, spayed female Domestic short hair cat presented with multiple black cutaneous plaques on the face and progressive lethargy. The cat's urine turned brown when exposed to air. The familial history of the cat was unknown. Clinical examination; histopathology, electron microscopy and mass/energy dispersive X-ray spectroscopy of tissues. Septic peritonitis and additional pigment in the spleen, intestine and lymph node were found at postmortem examination. The pigment was determined to be an organic compound and had a similar histological appearance, staining properties, ultrastructure and composition to ochronotic pigment. No mutations were found in exons 3, 6, 8 and 13 of the HGD gene in the cat. To the best of the authors' knowledge, this is the first report of a condition resembling ochronosis in a domestic animal species that has been evaluated with histopathology and advanced imaging techniques. It provides an additional differential in cases of aberrant pigmentation in cats. © 2016 ESVD and ACVD.

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.

Innervation of the anterior byssal retractor muscle in Mytilus edulis L. II. Ultrastructure of the glio-interstitial cells.

PubMed

Gilloteaux, J

1975-08-27

Studies on the intrinsic innervation of the anterior byssal retractor muscle (ABRM) in Mytilus edulis L. were continued at the ultrastructural level. Electron micrographs show nerve processes ensheathed by glio-interstitial cells running between muscle fibers. The glio-interstitial cells may represent all the types of osmiophilic cells previously described by the light microscopic ZIO technique in the anterior byssal retractor muscle.

Ulcerative colitis: ultrastructure of interstitial cells in myenteric plexus.

PubMed

Rumessen, J J; Vanderwinden, J-M; Horn, T

2010-10-01

Interstitial cells of Cajal (ICC) are key regulatory cells in the gut. In the colon of patients with severe ulcerative colitis (UC), myenteric ICC had myoid ultrastructural features and were in close contact with nerve terminals. In all patients as opposed to controls, some ICC profiles showed degenerative changes, such as lipid droplets and irregular vacuoles. Nerve terminals often appeared swollen and empty. Glial cells, muscle cells, and fibroblast-like cells (FLC) showed no alterations. FLC enclosed macrophages (MLC), which were in close contact with naked axon terminals. The organization and cytological changes may be of pathophysiological significance in patients with UC.

Ultrastructure and molecular characterization of Fusobacterium necrophorum biovars.

PubMed Central

Garcia, M M; Becker, S A; Brooks, B W; Berg, J N; Finegold, S M

1992-01-01

The ultrastructural features and molecular components of 18 strains of Fusobacterium necrophorum biovars A, AB and B, isolated from animal and human infections, were examined by electron microscopy, multilocus enzyme electrophoresis (MEE) and by sodium dodecyl sulfate-gradient polyacrylamide gel electrophoresis (SDS-PAGE). High resolution scanning electron microscopy revealed that the strains possessed a convoluted surface pattern. Transmission electron microscopy showed that all strains possessed a cell wall structure typical of gram-negative bacteria. Bleb formation was not uncommon. Numerous extracellular materials, resembling lipopolysaccharide (LPS) fragments, surrounded cells of both human strains and biovar B animal strains. Biovar A field strains revealed capsules as stained by ruthenium red whereas a stock culture strain showed the capsule only when immunostabilized with hyperimmune serum. Starch gel electrophoresis showed all strains to possess adenyl kinase, glutamate dehydrogenases and lactate dehydrogenase; each enzyme migrated uniformly (monomorphic) among the strains and represented an electrotype. However, SDS-PAGE indicated differences in the protein profiles between all of the strains; the most distinctly different was a human isolate (FN 606). Silver staining to detect LPS showed extensive "ladder" patterns among the majority of biovar A strains but not in the animal biovar B strains. Immunoblotting of LPS with a rabbit antiserum prepared against phenol extracted LPS from a biovar A animal isolate (LA 19) suggested marked variability in the LPS antigens among the isolates studied. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 7. Fig. 8. Fig. 9. PMID:1477801

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.

The ultrastructure and genetic traits of plants under the condition of hypobaric and hypoxia

NASA Astrophysics Data System (ADS)

Guo, Shuangsheng; Tang, Yongkang; Wang, Shulei; Cheng, Quanyong; Zhao, Qi

This study analyzed the cellular, sub-cellular and molecular levels, particle composition and volume changes of Indian lettuce under the conditions of hypobaric and hypoxia. Firstly, in the hypobaric and hypoxia conditions, two kinds of sample showed a decrease in the num-ber of cells, the increase in volume and the deflation in nuclear size. Secondly, Significant changes of the chloroplast ultrastructure have taken place in the two conditions. Thirdly, in the hypoxia condition, the chloroplast grana lamellae fractured and aggregated, which caused the chloroplasts to enlarge, their lamellae to reduce,become vaguer and finally to disintegrate. Fourthly, the volume change and aggregation of the chloroplasts induced mitochondria to ap-proach the chloroplasts. Fifthly, cytoskeleton immunofluorescence positioning results showed that the microtubules had decreased in number, shortened in length and gathered in the vicinity of the nucleus. In addition, total leaf DNA-sequence alignment found no rbcl gene mutation in the extreme conditions. Keywords: Chloroplast Ultrastructure Cytoskeleton rbcl gene Indian lettuce

Colorimeter and scanning electron microscopy analysis of teeth submitted to internal bleaching.

PubMed

Martin-Biedma, Benjamin; Gonzalez-Gonzalez, Teresa; Lopes, Manuela; Lopes, Luis; Vilar, Rui; Bahillo, José; Varela-Patiño, Purificación

2010-02-01

This in vitro study compared the tooth color and the ultrastructure of internal dental tissues before and after internal bleaching. Sodium perborate was placed in the pulp chamber of endodontically treated molars and sealed with intermediate restorative material. The test samples were stored in a physiologic solution, and the bleaching agent was replaced every 7 days. A control group was used. After 1 month, the colors of the test and control samples were measured with a colorimeter, and the internal surfaces were observed under field emission scanning electron microscopy (FESEM). Statistically significant differences were found between the test and control sample colors. The FESEM ultrastructure analysis of the internal enamel and dentin surfaces did not show any changes after the internal bleaching. The results of the present study show that sodium perborate is effective in bleaching nonvital teeth and does not produce ultrastructural changes in the dental tissues. Copyright 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

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

Rate of dehydration, state of subcellular organisation and nature of cryoprotection are critical factors contributing to the variable success of cryopreservation: studies on recalcitrant zygotic embryos of Haemanthus montanus.

PubMed

Sershen; Berjak, Patricia; Pammenter, N W; Wesley-Smith, James

2012-01-01

Effects of sequential procedures required for cryopreservation of embryos excised from the recalcitrant seeds of Haemanthus montanus were assessed ultrastructurally and in conjunction with respiratory activity and the rate of protein synthesis. Fresh material (water content, 5.05 ± 0.92 g g(-1) dry mass) afforded ultrastructural evidence of considerable metabolic activity, borne out by respiratory rates. Neither exposure to glycerol nor sucrose as penetrating and non-penetrating cryoprotectants, respectively, brought about degradative changes, although increased vacuolation and autophagy accompanied both, while respiratory and protein synthetic activity were not adversely affected. Glycerol-cryoprotected embryos flash dried to water contents >0.4 g g(-1) showed organised ultrastructural features and considerable autophagy consistent with metabolic activity, and although respiratory activity was lower, protein synthesis rate was enhanced relative to fresh material. However, at water contents <0.4 g g(-1), embryo tissue presented a mosaic of cells of variable density and ultrastructural status, but trends in rates of respiration and protein synthesis remained similar. Flash drying after sucrose exposure was accompanied by considerable ultrastructural abnormality particularly at water contents <0.4 g g(-1), lysis of individual and groups of cells and considerable depression of respiration, but not of protein synthesis. Success, assessed as ≥50% axes forming seedlings after cryogen exposure, was obtained only when glycerol-cryoprotected embryos at water contents >0.4 g g(-1)-in which the degree of vacuolation remained moderate-were rapidly cooled. The outcomes of this study are considered particularly in terms of the stresses imposed by prolonged, relatively slow dehydration and ultimate water contents, on embryos showing considerable metabolic activity.

Nucleolar structure across evolution: the transition between bi- and tri-compartmentalized nucleoli lies within the class Reptilia.

PubMed

Lamaye, Françoise; Galliot, Sonia; Alibardi, Lorenzo; Lafontaine, Denis L J; Thiry, Marc

2011-05-01

Two types of nucleolus can be distinguished among eukaryotic cells: a tri-compartmentalized nucleolus in amniotes and a bi-compartmentalized nucleolus in all the others. However, though the nucleolus' ultrastructure is well characterized in mammals and birds, it has been so far much less studied in reptiles. In this work, we examined the ultrastructural organization of the nucleolus in various tissues from different reptilian species (three turtles, three lizards, two crocodiles, and three snakes). Using cytochemical and immunocytological methods, we showed that in reptiles both types of nucleolus are present: a bi-compartmentalized nucleolus in turtles and a tri-compartmentalized nucleolus in the other species examined in this study. Furthermore, in a given species, the same type of nucleolus is present in all the tissues, however, the importance and the repartition of those nucleolar components could vary from one tissue to another. We also reveal that, contrary to the mammalian nucleolus, the reptilian fibrillar centers contain small clumps of condensed chromatin and that their surrounding dense fibrillar component is thicker. Finally, we also report that Cajal bodies are detected in reptiles. Altogether, we believe that these results have profound evolutionarily implications since they indicate that the point of transition between bipartite and tripartite nucleoli lies at the emergence of the amniotes within the class Reptilia. Copyright © 2011 Elsevier Inc. All rights reserved.

Postirradiation malignant fibrous histiocytoma of the lung. Demonstration of alpha 1-antitrypsin-like material in neoplastic cells.

PubMed

Chowdhury, L N; Swerdlow, M A; Jao, W; Kathpalia, S; Desser, R K

1980-12-01

A metastasizing fibrous histiocytoma arising in the lung of a patient who received radiation therapy and long-term chemotherapy for malignant lymphoma is presented. Ultrastructural studies revealed fibroblast-like and histiocyte-like cells, cells of intermediate type showing ultrastructural features of both fibroblast-like and histiocyte-like cells, primitive mesenchymal cells, multinucleate tumor cells, and xanthomatous cells. The neoplastic cells showed dilated rough endoplasmic reticula with intracisternal accumulation of electron-dense material forming lattice-like structures. Direct immunofluorescence staining of the neoplastic cells using antihuman alpha 1-antitrypsin showed specific activity, with fluorescent deposits exhibiting interlacing globular formations. These findings and their implications are discussed.

Ultrastructural examination of broncho-alveolar lavage for diagnosis of pulmonary histiocytosis X: Preliminary report on 4 cases.

PubMed Central

Basset, F; Soler, P; Jaurand, M C; Bignon, J

1977-01-01

Fibreoptic broncho-alveolar lavage was used in four patients; the diagnosis of histiocytosis X had been established by lung biopsy in three and was suggested on clinical grounds in the remaining patient. Characteristic cells with an ultrastructural cytoplasmic marker (X body) were found in the washes of all four patients. In the patient without biopsy confirmation, the findings in the broncho-aleolar washes supplied the corroborating evidence for the diagnosis. From this preliminary study the technique seems able to provide a diagnosis in pulmonary histiocytosis X without the need for an open lung biopsy. Images PMID:302040

Ultrastructure and ATPase activity of the rectal gland of the chondrichthyean fish Hydrolagus colliei (Holocephali).

PubMed

Lagios, M D; Stasko-Concannon, S

1979-05-18

The anatomy, histology, ultrastructure and ATPase activity of the intramural rectal gland of the chondrichthyean Hydrolagus colliei, are described. The cells of the rectal gland of Hydrolagus demonstrate the same well developed lateral and basal cisternae, elongate mitochondria and luminal border as those of their elasmobranch counterparts. ATPase activity within the rectal gland of Hydrolagus is as intense as that in a number of elasmobranchs examined in the course of the study. Despite its primitive intramural location the rectal gland of Hydrolagus represents a homolog of the more specialized and better known elasmobranch gland and appears as well suited for cation excretion.

Ultrastructure changes in buffalo (Bubalus bubalis) oocytes before and after maturation in vitro with sericin.

PubMed

Gustina, Sri; Hasbi, Hasbi; Karja, Ni Wayan Kurniani; Setiadi, Mohamad Agus; Supriatna, Iman

2017-12-01

The aim of this research was to identify the changes in the cytoplasmic ultrastructure of immature and matured oocytes in buffalo (Bubalus bubalis). Oocytes were matured in vitro in tissue culture medium-199 with and without sericin, and then analyzed by light and transmission electron microscopy. The experiment result showed that the nuclear maturation rate of buffalo oocytes was significantly higher in the presence of sericin (80.6%) than without sericin (68.1%) (P < 0.05). The immature oocytes were characterized by cortical granule clusters in the ooplasm and the absence of perivitelline space (PVS). In contrast, the oocytes matured either with or without sericin showed the formation of PVS, erected microvilli, the migration of cortical granules to the cytoplasmic periphery, and the clear appearance of the mitochondria and vesicle in the oolemma. Interestingly, matured oocytes with sericin have smaller cortical granules than do immature oocytes (P < 0.05). In conclusion, supplementation of 0.05% sericin in the maturation medium can enhance the maturation rate of buffalo oocytes. Several cytoplasmic ultrastructures were relocated and modulated during the in vitro maturation process of buffalo oocytes: PVS development, cortical granules migration to periphery, and mitochondria and vesicles in the cortical region. The ultrastructure was similar between the groups with and without sericin. © 2017 Japanese Society of Animal Science.

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.

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.

Meningioma-like tumor of the skin. An ultrastructural and immunohistochemical study.

PubMed

Barr, R J; Yi, E S; Jensen, J L; Wuerker, R B; Liao, S Y

1993-08-01

Three unusual cutaneous tumors are described along with ultrastructural and immunohistochemical studies. All lesions were asymptomatic red-brown papulonodules. Light microscopic examination revealed a whorled configuration of spindle-shaped cells, some concentrically arranged around blood vessels. Immunohistochemical panels exhibited positive staining only with antibody to vimentin and negative staining with antibodies against S-100 protein, muscle markers, cytokeratin, epithelial membrane antigen, Leu 7, type IV collagen, and factor XIIIa, ruling out obvious nevomelanocytic, nerve sheath, meningothelial, smooth muscle, and perithelial differentiation. Electron microscopic examination demonstrated cells producing poorly formed collagen fibrils, sparse collagen fibers, and possessing occasional ill-defined intercellular junctions between their elongated cell processes. This rare tumor is considered to be either an immature fibrohistiocytic or possibly a nerve sheath neoplasm with striking similarities to so-called canine hemangiopericytoma. Because the prominent whorled pattern was reminiscent of meningioma, the lesion was referred to as meningioma-like tumor of the skin.

Application of atomic force microscopy to microbial surfaces: from reconstituted cell surface layers to living cells.

PubMed

Dufrêne, Y F

2001-02-01

The application of atomic force microscopy (AFM) to probe the ultrastructure and physical properties of microbial cell surfaces is reviewed. The unique capabilities of AFM can be summarized as follows: imaging surface topography with (sub)nanometer lateral resolution; examining biological specimens under physiological conditions; measuring local properties and interaction forces. AFM is being used increasingly for: (i) visualizing the surface ultrastructure of microbial cell surface layers, including bacterial S-layers, purple membranes, porin OmpF crystals and fungal rodlet layers; (ii) monitoring conformational changes of individual membrane proteins; (iii) examining the morphology of bacterial biofilms, (iv) revealing the nanoscale structure of living microbial cells, including fungi, yeasts and bacteria, (v) mapping interaction forces at microbial surfaces, such as van der Waals and electrostatic forces, solvation forces, and steric/bridging forces; and (vi) probing the local mechanical properties of cell surface layers and of single cells.

Pathological investigation of caries and occlusal pulpar exposure in donkey cheek teeth using computerised axial tomography with histological and ultrastructural examinations.

PubMed

Toit, Nicole du; Burden, Faith A; Kempson, Sue A; Dixon, Padraic M

2008-12-01

Post-mortem examination of 16 donkey cheek teeth (CT) with caries (both peripheral and infundibular) and pulpar exposure were performed using computerised axial tomography (CAT), histology and scanning electron microscopy. CAT imaging was found to be useful to assess the presence and extent of caries and pulp exposure in individual donkey CT. Histology identified the loss of occlusal secondary dentine, and showed pulp necrosis in teeth with pulpar exposure. Viable pulp was present more apically in one exposed pulp horn, with its occlusal aspect sealed off from the exposed aspect of the pulp horn by a false pulp stone. Scanning electron microscopy showed the amelo-cemental junction to be a possible route of bacterial infection in infundibular cemental caries. The basic pathogenesis of dental caries in donkeys appears very similar to its description in other species.

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.

Low Night Temperature Affects the Phloem Ultrastructure of Lateral Branches and Raffinose Family Oligosaccharide (RFO) Accumulation in RFO-Transporting Plant Melon (Cucumismelo L.) during Fruit Expansion

PubMed Central

Hao, Jinghong; Gu, Fengying; Zhu, Jie; Lu, Shaowei; Liu, Yifei; Li, Yunfei; Chen, Weizhi; Wang, Liping; Fan, Shuangxi; Xian, Cory J.

2016-01-01

Due to the importance and complexity of photo assimilate transport in raffinose family oligosaccharide (RFO)-transporting plants such as melon, it is important to study the features of the transport structure (phloem) particularly of the lateral branches connecting the source leaves and the sink fruits, and its responses to environmental challenges. Currently, it is unclear to what extents the cold environmental temperature stress would alter the phloem ultrastructure and RFO accumulation in RFO-transporting plants. In this study, we firstly utilized electron microscopy to investigate the changes in the phloem ultrastructure of lateral branches and RFO accumulation in melons after being subjected to low night temperatures (12°C and 9°C). The results demonstrated that exposure to 9°C and 12°C altered the ultrastructure of the phloem, with the effect of 9°C being more obvious. The most obvious change was the appearance of plasma membrane invaginations in 99% companion cells and intermediary cells. In addition, phloem parenchyma cells contained chloroplasts with increased amounts of starch grains, sparse cytoplasm and reduced numbers of mitochondria. In the intermediary cells, the volume of cytoplasm was reduced by 50%, and the central vacuole was present. Moreover, the treatment at 9°C during the night led to RFO accumulation in the vascular bundles of the lateral branches and fruit carpopodiums. These ultrastructural changes of the transport structure (phloem) following the treatment at 9°C represented adaptive responses of melons to low temperature stresses. Future studies are required to examine whether these responses may affect phloem transport. PMID:27501301

Low Night Temperature Affects the Phloem Ultrastructure of Lateral Branches and Raffinose Family Oligosaccharide (RFO) Accumulation in RFO-Transporting Plant Melon (Cucumismelo L.) during Fruit Expansion.

PubMed

Hao, Jinghong; Gu, Fengying; Zhu, Jie; Lu, Shaowei; Liu, Yifei; Li, Yunfei; Chen, Weizhi; Wang, Liping; Fan, Shuangxi; Xian, Cory J

2016-01-01

Due to the importance and complexity of photo assimilate transport in raffinose family oligosaccharide (RFO)-transporting plants such as melon, it is important to study the features of the transport structure (phloem) particularly of the lateral branches connecting the source leaves and the sink fruits, and its responses to environmental challenges. Currently, it is unclear to what extents the cold environmental temperature stress would alter the phloem ultrastructure and RFO accumulation in RFO-transporting plants. In this study, we firstly utilized electron microscopy to investigate the changes in the phloem ultrastructure of lateral branches and RFO accumulation in melons after being subjected to low night temperatures (12°C and 9°C). The results demonstrated that exposure to 9°C and 12°C altered the ultrastructure of the phloem, with the effect of 9°C being more obvious. The most obvious change was the appearance of plasma membrane invaginations in 99% companion cells and intermediary cells. In addition, phloem parenchyma cells contained chloroplasts with increased amounts of starch grains, sparse cytoplasm and reduced numbers of mitochondria. In the intermediary cells, the volume of cytoplasm was reduced by 50%, and the central vacuole was present. Moreover, the treatment at 9°C during the night led to RFO accumulation in the vascular bundles of the lateral branches and fruit carpopodiums. These ultrastructural changes of the transport structure (phloem) following the treatment at 9°C represented adaptive responses of melons to low temperature stresses. Future studies are required to examine whether these responses may affect phloem transport.

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

PubMed

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

1988-11-01

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

Pectus carinatum--first ultrastructural findings of a potential metabolic lesion.

PubMed

Brochhausen, Christoph; Müller, Felix Karl P; Turial, Salmai; James Kirkpatrick, C

2012-03-01

The histological and ultrastructural findings of rib specimens after two re-interventions in the case of recurrence of pectus carinatum (PC) are presented in this report. A 15-year-old boy developed recurrences of mild PC after re-chondroplasties using the Ravitch technique. Histological study of the resected cartilage showed markedly degenerative changes of the sternocostal cartilage. For the first time, intracellular crystalline inclusions in some of the chondrocytes were found. These findings indicate metabolic changes as a possible pathogenetic parameter in PC.

Ultrastructural findings in lung biopsy material from children with congenital heart defects.

PubMed Central

Meyrick, B.; Reid, L.

1980-01-01

The ultrastructural features of pulmonary arteries are described in lung biopsy material from 6 children with congenital heart defects. Right ventricular hypertrophy was found in all 6 children and increased pulmonary artery pressure in all but one. The presence of muscle in smaller and more peripheral arteries than expected for the age of the child was detected in all cases. Ultrastructural examination of the peripheral arteries revealed, for the first time, in the nonmuscular regions of human arterial walls, pericytes and intermediate cells (previously shown to be precursor smooth-muscle cells); in addition, new arterial muscle was found in the normally nonmuscular region. In the 4 cases where medial thickness of the normally muscular arteries was increased, the smooth-muscle cells were hypertrophied and the extracellular connective tissue increased. In all cases, junctions between endothelial cells and smooth-muscle cells, intermediate cells, or pericytes were found. These changes are similar to those described in the rat with hypoxia-induced pulmonary hypertension. In addition, in 2 of the 6 cases, bundles of nerve axons in Schwann cell sheaths were found in adventitial layer of small, intraacinar muscular arteries (not previously demonstrated ultrastructurally at this site in the human lung); varicosities with agranular and granular vesicles, probably adrenergic, were also identified. Images Figure 4 Figure 5 Figure 1 Figure 2 Figure 3 PMID:7446706

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.

A new technique for the rapid screening and selection of large pieces of tissue for ultrastructural evaluation.

PubMed

Dalley, B K; Seliger, W G

1980-05-01

A simple and rapid technique is described for the screening of Epon embedded organ slices for the location, isolation, and removal of small specific sites for ultrastructural study with the transmission electron microscope. This procedure consists of perfusion fixation followed by making 1 to 21/2 mm thick slices of relatively large pieces of the organs, control of the degree and evenness of the osmium staining by addition of 3% sodium iodate, and infiltration with a fluorescent dye prior to embedment in Epon. Tissue slices are embedded in wafer-shaped blocks, generally with several slices in one "wafer", and are examined in a controlled manner using a rapid form of serial surface polishing. Each level of the polished wafer is examined using an epi-illuminated fluorescence microscope, and selected sites are chosen at each level for ultrastructural study. Methods are also described for marking each selected site using a conventional slide marker, and for the removal of the selected site in the form of a small disc of Epon, after which the Epon wafer can be further serially polished and the examination continued. Areas to be thin-sectioned are removed using a core drill mounted on a model-maker's drill press. The technique is simple, does not require the destruction of remaining tissues to evaluate more critically a single small site, allows for the easy maintenance of tissue orientation, and the most time-consuming portions of the technique can be quickly taught to a person with no previous histological training.

Autophagic activity in the mouse urinary bladder urothelium as a response to starvation.

PubMed

Erman, Andreja; Resnik, Nataša; Romih, Rok

2013-02-01

The urinary bladder urothelium is subjected to mechanical forces during cycles of distension and contraction, and its superficial cells are constantly flushed by toxic urine. Yet, the urothelium shows a very slow turnover of cells and superficial cells are extremely long lived. Autophagy has a well-known role in tissue homeostasis and serves as a protective mechanism against cellular stress. Therefore, the presence of autophagy as one of possible processes of survival in an unpleasant environment and during long lifetime of superficial cells was examined in mouse urothelium. We detected and evaluated autophagic activity of superficial urothelial cells under normal and stress conditions, caused by short-term starvation of newborn and 24-h-starved adult mice. Immunolabeling and Western blotting of essential effectors of autophagy, LC3 and Beclin 1, showed a weak signal in superficial urothelial cells. On the other hand, ultrastructural analysis, which proved to be the most reliable method in our study, revealed the presence of autophagic vacuoles, some of them containing specific urothelial structures, fusiform vesicles. Quantitative analysis showed increased autophagy in newborn and starved mice in comparison to a low basic level of autophagy in the urothelium of normal mice. Interestingly, some superficial cells of adults and neonates exhibit intense immunoreactions against LC3 and Beclin 1 and the typical ultrastructural characteristics of autophagy-dependent cell death. We conclude that autophagy, despite low basic activity under physiological conditions, plays an important role in urothelial homeostasis and stability under stress.

Ameliorative effect of Pimpinella anisum oil on immunohistochemical and ultrastuctural changes of cerebellum of albino rats induced by aspartame.

PubMed

Abdul-Hamid, Manal; Gallaly, Sanaa Rida

2014-05-01

The study aims to investigate the protective effect of Pimpinella anisum oil on aspartame (ASP) which resulted in cerebellar changes. The rats were divided into four equal groups: Group 1: (control group): served as control animals. Group 2: control P. anisum oil received .5 mL/kg/d/b wt. once daily. Group 3 (ASP group): received daily 250 mg/kg/b wt. of ASP dissolved in distilled water and given orally to the animals by intra-gastric tube for 2 months. Group 4: received .5 mL/kg/b wt. of prophylactic P. anisum oil once daily, followed by ASP after 2 h for 2 months. The histopathological approach revealed marked changes in the Purkinje cells, myleinated nerve fibers and granular cells of ASP-treated animals. Some of these cells appeared with deeply stained cytoplasm. Ultrastructural examination showed Purkinje cells with dilated rough endoplasmic reticulum and condensed mitochondria. Granular cells appeared with less c nuclei and surrounded by dissolution of most Mossy rosettes structures. Most myelinated nerve fibers showed thickening of myelinated sheath and others showed splitting of their myelin sheath. The histopathological, immunohistochemical and ultrastructural alterations were much less observed in concomitant use of P. anisum oil with ASP. Cerebellar cortex is considered target areas of ASP neurotoxicity, while P. anisum oil, when used in combination with ASP displays a protective action against neurotoxicity.

Genome duplication improves rice root resistance to salt stress

PubMed Central

2014-01-01

Background Salinity is a stressful environmental factor that limits the productivity of crop plants, and roots form the major interface between plants and various abiotic stresses. Rice is a salt-sensitive crop and its polyploid shows advantages in terms of stress resistance. The objective of this study was to investigate the effects of genome duplication on rice root resistance to salt stress. Results Both diploid rice (HN2026-2x and Nipponbare-2x) and their corresponding tetraploid rice (HN2026-4x and Nipponbare-4x) were cultured in half-strength Murashige and Skoog medium with 150 mM NaCl for 3 and 5 days. Accumulations of proline, soluble sugar, malondialdehyde (MDA), Na+ content, H+ (proton) flux at root tips, and the microstructure and ultrastructure in rice roots were examined. We found that tetraploid rice showed less root growth inhibition, accumulated higher proline content and lower MDA content, and exhibited a higher frequency of normal epidermal cells than diploid rice. In addition, a protective gap appeared between the cortex and pericycle cells in tetraploid rice. Next, ultrastructural analysis showed that genome duplication improved membrane, organelle, and nuclei stability. Furthermore, Na+ in tetraploid rice roots significantly decreased while root tip H+ efflux in tetraploid rice significantly increased. Conclusions Our results suggest that genome duplication improves root resistance to salt stress, and that enhanced proton transport to the root surface may play a role in reducing Na+ entrance into the roots. PMID:25184027

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.

Ceroid-lipofuscinosis in border collie dogs.

PubMed

Taylor, R M; Farrow, B R

1988-01-01

Five Border Collie dogs with ceroid-lipofuscinosis developed progressive neurological disease between 18 and 22 months of age. These dogs had behavioural abnormalities, gait and visual deficits and became progressively demented. All dogs examined had common ancestors. Light microscopic examination of tissues demonstrated extensive accumulation of granular, sudan black-staining autofluorescent material in the cytoplasm of neurones, retinal ganglion cells and some visceral cells. At ultrastructural examination inclusions of variable morphology were observed.

Characterization of internal structure of hydrated agar and gelatin matrices by cryo-SEM.

PubMed

Rahbani, Janane; Behzad, Ali R; Khashab, Niveen M; Al-Ghoul, Mazen

2013-02-01

There has been a considerable interest in recent years in developing polymer gel matrices for many important applications such as 2DE for quantization and separation of a variety of proteins and drug delivery system to control the release of active agents. However, a well-defined knowledge of the ultrastructures of the gels has been elusive. In this study, we report the characterization of two different polymers used in 2DE: Gelatin, a naturally occurring polymer derived from collagen (protein) and agar, a polymer of polysaccharide (sugar) origin. Low-temperature SEM is used to examine the internal structure of these gels in their frozen natural hydrated states. Results of this study show that both polymers have an array of hollow cells that resembles honeycomb structures. While agar pores are almost circular, the corresponding Gaussian curve is very broad exhibiting a range of radii from nearly 370 to 700 nm. Gelatin pores are smaller and more homogeneous reflecting a narrower distribution from nearly 320 to 650 nm. Overall, these ultrastructural findings could be used to correlate with functions of the polymers. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Pulmonary microvascular dysfunction and pathological changes induced by blast injury in a rabbit model.

PubMed

Wu, Si Yu; Han, Geng Fen; Kang, Jian Yi; Zhang, Liang Chao; Wang, Ai Min; Wang, Jian Min

2016-09-01

Vascular leakage has been proven to play a critical role in the incidence and development of explosive pulmonary barotrauma. Quantitatively investigated in the present study was the severity of vascular leakage in a gradient blast injury series, as well as ultrastructural evidence relating to pulmonary vascular leakage. One hundred adult male New Zealand white rabbits were randomly divided into 5 groups according to distance from the detonator (10 cm, 15 cm, 20 cm, 30 cm, and sham control). Value of pulmonary vascular leakage was monitored by a radioactive 125I-albumin labeling method. Pathological changes caused by the blast wave were examined under light and electron microscopes. Transcapillary escape rate of 125I-albumin and residual radioactivity in both lungs increased significantly at the distances of 10 cm, 15 cm, and 20 cm, suggesting increased severity of vascular leakage in these groups. Ultrastructural observation showed swelling of pulmonary capillary endothelial cells and widened gap between endothelial cells in the 10-cm and 15-cm groups. Primary blast wave can result in pulmonary capillary blood leakage. Blast wave can cause swelling of pulmonary capillary endothelial cells and widened gap between endothelial cells, which may be responsible for pulmonary vascular leakage.

Ultrastructure and Glycoconjugate Pattern of the Foot Epithelium of the Abalone Haliotis tuberculata (Linnaeus, 1758) (Gastropoda, Haliotidae)

PubMed Central

Bravo Portela, I.; Martinez-Zorzano, V. S.; Molist- Perez, I.; Molist García, P.

2012-01-01

The foot epithelium of the gastropod Haliotis tuberculata is studied by light and electron microscopy in order to contribute to the understanding of the anatomy and functional morphology of the mollusks integument. Study of the external surface by scanning electron microscopy reveals that the side foot epithelium is characterized by a microvillus border with a very scant presence of small ciliary tufts, but the sole foot epithelium bears a dense field of long cilia. Ultrastructural examination by transmission electron microscopy of the side epithelial cells shows deeply pigmented cells with high electron-dense granular content which are not observed in the epithelial sole cells. Along the pedal epithelium, seven types of secretory cells are present; furthermore, two types of subepithelial glands are located just in the sole foot. The presence and composition of glycoconjugates in the secretory cells and subepithelial glands are analyzed by conventional and lectin histochemistry. Subepithelial glands contain mainly N-glycoproteins rich in fucose and mannose whereas secretory cells present mostly acidic sulphated glycoconjugates such as glycosaminoglycans and mucins, which are rich in galactose, N-acetyl-galactosamine, and N-acetyl-glucosamine. No sialic acid is present in the foot epithelium. PMID:22645482

Changes in Ultrastructure and Sensory Characteristics on Electro-magnetic and Air Blast Freezing of Beef during Frozen Storage

PubMed Central

2015-01-01

The ultrastructure in the beef muscle of the electro-magnetic resonance and air blast freezing during the frozen storage, and the changes in the quality characteristics after thawing were evaluated. The size of ice crystal was small and evenly formed in the initial freezing period, and it showed that the size was increased as the storage period was elapsed (p<0.05). The beef stored by the electro-magnetic resonance freezing showed the size of ice crystal with a lower rate of increase than the air blast freezing during the frozen storage. The thawing loss of beef stored by the electro-magnetic resonance freezing was significantly lower than the air blast freezing during frozen storage (p<0.05), and it showed that the thawing loss of the round was higher than the loin. Water holding capacity decreased as the storage period became longer while the electro-magnetic resonance freezing was higher than the air blast on 8 month (p<0.05). As a result of sensory evaluation, the beef stored by the electro-magnetic resonance freezing did not show the difference until 4 months, and it showed higher acceptability in comparison with the beef stored by the air blast freezing. Thus, it is considered that the freezing method has an effect on the change in the ultrastructure and quality characteristics of the beef. PMID:26761797

Ultrastructural 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

Ultrastructural blood-brain barrier alterations and edema formation in acute spinal cord trauma.

PubMed

Goodman, J H; Bingham, W G; Hunt, W E

1976-04-01

Endothelial changes leading to edema formation are examined in the primate spinal cord (Macaca mulatta) following a lesion created by a 20-gm weight falling 15 cm onto the exposed dura. Intravascular perfusion of a paraformaldehydeglutaraldehyde solution followed by carbon black provides adequate fixation of vascular structures and glial elements. Myelin is poorly preserved. Ultrastructural alterations of the blood-brain barrier consist of loss of integrity of the endothelial tight junctions. Edema caused by vascular disruption and parenchymatous extravasation of intravascular contents is observed along with glial swelling. Interglial gap junctions persist in areas of marked cellular seperation and do not impede the migration of edema fluid.

Histochemical and ultrastructural study of the chicken salivary palatine glands.

PubMed

Samar, María E; Avila, Rodolfo E; Esteban, Francisco J; Olmedo, Luis; Dettin, Luis; Massone, Adriana; Pedrosa, Juan A; Peinado, María A

2002-01-01

Salivary glands are a good model to investigate the relationship between cell secretion and glandular structure. Most studies of this organ deal with mammals, but we are interested in a morphofunctional characterization of these glands in poultry in relation with particular feeding habits. For this purpose, conventional and lectin histochemical methods as well as ultrastructural methods have been applied to the chicken lateral and medial palatine salivary glands. It was found that periodic acid-Schiff (PAS)-positive, alcianophilic, and metachromatic or orthochromatic cells were present with a more homogeneous distribution pattern in lateral glands than in medial palatine glands. Lectin staining depended on the lectin type that was applied, but also on the glandular part both in lateral and medial glands. Ultrastructural studies showed cytoplasmic membranous structures with a scattered granular or filamentous content depending on the secretory cell. In conclusion, morphofunctional characteristics of salivary glands of chicken suggest that their products are involved in lubrication and humidification of food ingested, and probably in protection of the oral surface, as has been previously described for other animals showing similar histochemical staining patterns.

Chromaffin granules in the rat adrenal medulla release their secretory content in a particulate fashion.

PubMed

Crivellato, Enrico; Belloni, Anna; Nico, Beatrice; Nussdorfer, Gastone G; Ribatti, Domenico

2004-03-01

Exocytosis is considered the main route of granule discharge in chromaffin cells. We recently provided ultrastructural evidence suggesting that piecemeal degranulation (PMD) occurs in mouse adrenal chromaffin cells. In the present study, we processed rat adrenal glands for transmission electron microscopy (TEM), and examined chromaffin cells for changes characteristic of PMD. Both adrenaline (A)- and noradrenaline (NA)-storing cells express ultrastructural features suggestive of a slow and particulate mode of granule discharge. In adrenaline-containing cells, some granules present enlarged dimensions accompanied by eroded or dissolved matrices. Likewise, a number of granules in NA-releasing cells show content reduction with variably expanded granule chambers. Dilated, empty granule containers are recognizable in the cytoplasm of both cell types. Characteristically, altered granules and empty containers are seen intermingled with normal, resting granules. In addition, chromaffin granules often show irregular profiles, with budding or tail-like projections of their limiting membranes. Thirty 150-nm-diameter membrane-bound vesicles with a moderately electron-dense or -lucent internal structure are observable in the cytoplasm of both cell types. These vesicles are seen among the granules and some of them are fused with the perigranule membranes in the process of attachment to or budding from the granules. These data add further support to the concept that PMD may be an alternative secretory pathway in adrenal chromaffin cells. Copyright 2004 Wiley-Liss, Inc.

First ultrastructural observations on gastritis caused by Physaloptera clausa (Spirurida: Physalopteridae) in hedgehogs (Erinaceus europeaus).

PubMed

Gorgani-Firouzjaee, T; Farshid, A A; Naem, S

2015-10-01

Ultrastructural changes of gastritis due to infection with Physaloptera clausa in 12 fresh carcasses of euthanized European hedgehogs (Erinaceus europaeus) collected from different part of Urmia, Iran, in which they were highly populated with this animal, six females and six males were subjected to detail necropsy with special reference to the stomach. Macroscopic changes of stomach were recorded and some of the worms collected. Based on number of parasites present in the stomach, they were divided into light infection, mild infection, and severe infection. Parasites were collected, and worms identification of the species was confirmed on the basis of light microscope examination with reference to keys. Tissues fixed in 3% glutaraldehyde, post-fixed in 1% osmium tetroxide and processed and plastic embedded; ultrathin sections of 60-70 nm were cut and stained with uranyl acetate and lead citrate; electron microscopic observations showed that, in light infection some changes were observed in gastric cells such as dilatation and vesiculation of the endoplasmic reticulum, large numbers of lipid granules, mitochondrial swelling, nuclear chromatin margination, and some nucleus showed washed out appearance. Other cells showed some alterations in mitochondria, dilatation of smooth endoplasmic reticulum, loss of both free and bound ribosomes, vesiculation in cytoplasm, and increase Golgi apparatus and secretory vesicles. The inflammatory cells including lymphocytes, macrophages, mast cells, and predominantly eosinophils were identified. In moderate infection, the cellular pattern of gastric mucosa replaced with inflammatory cells. The marked increase of macrophages and other inflammatory cell was observed. A particular finding in our study was the presence of globule leukocyte in the moderate stage. Moreover, scant formation and distribution of collagen fibers as well as fibroblasts were also noted. In severe infection, the most obvious observation was marked distribution of collagen fibers around the mucosal cells. The fibroblastic cells with elongated nucleus and extensive indentation were noticed. In conclusion, the result of our study revealed P. clausa could be a cause of gastritis and according to cellular pattern of inflammatory reaction, with the increase of worm burden and development of infection, chronic gastritis was stabilized. Present investigation documented the ultrastructural changes during verminous gastritis in hedgehogs.

Ultrastructural effects of AAL-toxin TA from the fungus Alternaria alternata on black nightshade (Solanum nigrum L.) leaf discs and correlation with biochemical measures of toxicity.

PubMed

Abbas, H K; Paul, R N; Riley, R T; Tanaka, T; Shier, W T

1998-12-01

Ultrastructural effects of AAL-toxin TA from Alternaria alternata on black nightshade (Solanum, nigrum L.) leaf discs and correlation with biochemical measures of toxicity. In black nightshade (Solanum nigrum L.) leaf discs floating in solutions of AAL-toxin TA (0.01-200 microM) under continuous light at 25 degrees C, electrolyte leakage, chlorophyll loss, autolysis, and photobleaching were observed within 24 h. Electrolyte leakage, measured by the conductivity increase in the culture medium, began after 12 h with 200 microM AAL-toxin T(A), but was observed after 24 h with 0.01 to 50 microM AAL-toxin T(A), when it ranged from 25%) to 63% of total releasable electrolytes, respectively. After 48 h incubation, leakage ranged from 39% to 79% of total for 0.01 to 200 microM AAL-toxin T(A), respectively, while chlorophyll loss ranged from 5% to 32% of total, respectively. Ultrastructural examination of black night-shade leaf discs floating in 10 microM AAL-toxin TA under continuous light at 25 degrees C revealed cytological damage beginning at 30 h, consistent with the time electrolyte leakage and chlorophyll reduction were observed. After 30 h incubation chloroplast starch grains were enlarged in control leaf discs, but not in AAL-toxin T(A)-treated discs, and the thylakoids of treated tissue contained structural abnormalities. After 36-48 h incubation with 10 microM AAL-toxin T(A), all tissues were destroyed with only cell walls, starch grains, and thylakoid fragments remaining. Toxicity was light-dependent, because leaf discs incubated with AAL-toxin T(A) in darkness for up to 72 h showed little phytotoxic damage. Within 6 h of exposure to > or =0.5 microM toxin, phytosphingosine and sphinganine in black nightshade leaf discs increased markedly, and continued to increase up to 24 h exposure. Thus, phy siological and ultrastructural changes occurred in parallel with disruption of sphingolipid synthesis, consistent with the hypothesis that AAL-toxin T(A) causes phytotoxicity by interrupting sphingolipid biosynthesis, thereby damaging cellular membranes.

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.

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.

Long term effects of low doses of Fe-56 ions on the brain and retina of the mouse - Ultrastructural and behavioral studies

NASA Technical Reports Server (NTRS)

Philpott, Delbert E.; Miquel, Jaime

1986-01-01

Eight-month-old male C57BL6 mice were exposed without anesthesia to whole-body irradiation in circular holders. The mice were tested for behavioral decrements after 0.5 and 50 rads of Fe particle irradiation at 6 and 12 months postirradiation to obtain long-term results. A standard maze was used, and the animals were timed for completion thereof. A string test also was administered to the mice, testing their ability to grasp and move along a string to safety. The results from animals exposed to 50 rads were significantly different from control results to p = less than 0.001 in both systems of testing. The hippocampus (believed to be the location of environmental interaction in the brain) and the retina were examined for ultrastructural changes. The ultrastructural changes were similar to those found in the Cosmos 782, 936, and Argon experiments. The mouse data indicate that iron particles were able to induce long-term changes in the central nervous system which led to behavioral impairment.

An ultrastructural and immunogold localization study of proteoglycans associated with the osteocytes of fetal bone in osteogenesis imperfecta.

PubMed

Sarathchandra, P; Pope, F M; Ali, S Y

1996-06-01

Osteogenesis imperfecta (OI) is a rare, heterogeneous, inherited connective tissue disorder frequently caused by abnormalities of type I collagen. It is characterized by bone fragility, osteopenia, and progressive skeletal deformities. Electron microscopy of three OI type II fetal bone samples revealed numerous large osteocyte lacunae. In addition, there was a perilacunar osteoid-like band of collagen surrounding the osteocytes, which was unmineralized and morphologically unusual. Furthermore, large osteocyte lacunae contained fine particles and filamentous material similar to the expected ultrastructural appearance of proteoglycans. More detailed examination was carried out using histochemical and immunogold localization of proteoglycans at light and ultrastructural levels. These tests and the use of electron probe X-ray microanalysis confirmed that the material in the osteocyte lacunae was proteoglycan. In contrast, in the age- and site-matched normal fetal bone, all the osteocyte lacunae appeared negative for proteoglycan. Proteoglycans are regarded as inhibitors of calcification. Our observation of substantial amounts of proteoglycan in abnormally enlarged osteocytic lacunae of some OI fetal bone suggests association with the abnormal bone of this particular subtype of OI type II.

Long term effects of low doses of 56Fe ions on the brain and retina of the mouse: ultrastructural and behavioral studies

NASA Technical Reports Server (NTRS)

Philpott, D. E.; Miquel, J.

1986-01-01

Eight month old male C57BL6 mice were exposed without anesthesia to whole-body irradiation in circular holders. The mice were tested for behavioral decrements after 0.5 and 50 rads of Fe particle irradiation at 6 and 12 months post irradiation to obtain long term results. A standard maze was used and the animals were timed for completion thereof. A string test also was administered to the mice, testing their ability to grasp and move along a string to safety. The results from animals exposed to 50 rads were significantly different from [correction of fron] control results to p = < .001 in both systems of testing. The hippocampus (believed to be the location of environmental interaction in the brain) and the retina were examined for ultrastructural changes. The ultrastructural changes were similar to those we found in our Cosmos 782, 936 and in our Argon experiments. The mouse data indicate that iron particles were able to induce long term changes in the central nervous system which lead to behavioral impairment.

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.

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

Ultrastructural evidence of a vesicle-mediated mode of cell degranulation in chicken chromaffin cells during the late phase of embryonic development

PubMed Central

Crivellato, Enrico; Nico, Beatrice; Travan, Luciana; Isola, Miriam; Ribatti, Domenico

2009-01-01

In the present investigation, we attempted to determine whether ultrastructural features indicative of a vesicle-mediated mode of cell secretion were detectable in chick chromaffin cells during embryo development. The adrenal anlagen of domestic fowls were examined at embryonic days (E) 12, 15, 19 and 21 by electron microscopy quantitative analysis. Morphometric evaluation revealed a series of granule and cytoplasmic changes highly specific for piecemeal degranulation (PMD), a secretory process based on vesicular transport of cargoes from within granules for extracellular release. At E19 and E21 we found a significant peak in the percentage of granules exhibiting changes indicative of progressive release of secretory materials, i.e. granules with lucent areas in their cores, reduced electron density, disassembled matrices, residual cores and membrane empty containers. A dramatic raise in the density of 30–80-nm-diameter, membrane-bound, electron-dense and electron-lucent vesicles – which were located either next to granules or close to the plasma membrane – was recognizable at E19, that is, during the prehatching phase. The cytoplasmic burst of dense and clear vesicles was paralleled by the appearance of chromaffin granules showing outpouches or protrusions of their profiles (‘budding features’). These ultrastructural data are indicative of an augmented vesicle-mediated transport of chromaffin granule products for extracellular release in chick embryo chromaffin cells during the prehatching stage. In conclusion, this study provides new data on the fine structure of chromaffin cell organelles during organ development and suggests that PMD may be part of an adrenomedullary secretory response that occurs towards the end of chicken embryogenesis. From an evolutionary point of view, this study lends support to the concept that PMD is a secretory mechanism highly conserved throughout vertebrate classes. PMID:19245498

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

PubMed

Sever, David M; Freeborn, Layla R

2012-03-01

The anterior testicular ducts of squamates transport sperm from the seminiferous tubules to the ductus deferens. These ducts consist of the rete testis, ductuli efferentes, and ductus epididymis. Many histological and a few ultrastructural studies of the squamate reproductive tract exist, but none concern the Hydrophiidae, the sea snakes and sea kraits. In this study, we describe the anterior testicular ducts of six species of hydrophiid snakes as well as representatives from the Elapidae, Homolapsidae, Leptotyphlopidae, and Uropeltidae. In addition, we examine the ultrastructure of these ducts in the yellow-bellied Sea Snake, Pelamis platurus, only the third such study on snakes. The anterior testicular ducts are similar in histology in all species examined. The rete testis is simple squamous or cuboidal epithelium and transports sperm from the seminiferous tubules to the ductuli efferentes in the extratesticular epididymal sheath. The ductuli efferentes are branched, convoluted tubules composed of simple cuboidal, ciliated epithelium, and many species possess periodic acid-Schiff+ granules in the cytoplasm. The ductus epididymis at the light microscopy level appears composed of pseudostratified columnar epithelium. At the ultrastructural level, the rete testis and ductuli efferentes of P. platurus possess numerous small coated vesicles and lack secretory vacuoles. Apocrine blebs in the ductuli efferentes, however, indicate secretory activity, possibly by a constitutive pathway. Ultrastructure reveals three types of cells in the ductus epididymis of P. platurus: columnar principal cells, squamous basal cells, and mitochondria-rich apical cells. This is the first report of apical cells in a snake. In addition, occasional principal cells possess a single cilium, which has not been reported in reptiles previously but is known in some birds. Finally, the ductus epididymis of P. platurus differs from other snakes that have been studied in possession of apical, biphasic secretory vacuoles. All of the proximal ducts are characterized by widening of adjacent plasma membranes into wide intercellular spaces, especially between the principal cells of the ductus epididymis. Our results contribute to a larger, collaborative study of the evolution of the squamate reproductive tract and to the potential for utilizing cellular characters in future phylogenetic inferences. Copyright © 2011 Wiley Periodicals, Inc.

The Antibacterial Activity of Coriolus versicolor Methanol Extract and Its Effect on Ultrastructural Changes of Staphylococcus aureus and Salmonella Enteritidis.

PubMed

Matijašević, Danka; Pantić, Milena; Rašković, Božidar; Pavlović, Vladimir; Duvnjak, Dunja; Sknepnek, Aleksandra; Nikšić, Miomir

2016-01-01

The antibacterial activity of methanol extract obtained from fruiting body of industrially grown basidiomycete Coriolus versicolor was examined. The Minimum Inhibitory Concentration (MIC) values against various bacteria ranged from 0.625 to 20 mg mL(-1). C. versicolor expressed bactericidal activity against both Gram-positive and Gram-negative bacteria. The growth curves of Staphylococcus aureus and Salmonella enterica serovar Enteritidis, measured at 630 nm, and confirmed with macrodilution method showed that the obtained extract could inhibit the growth of tested bacteria. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and the loss of 260-nm-absorbing material were used to examine the ultrastructural changes in bacteria induced by the extract. When S. aureus was exposed to the MIC of C. versicolor, elongated and malformed cells were observed by SEM, while S. Enteritidis treated cells appeared shorter and aggregated with ruptured cell walls. TEM revealed the formation of non-membrane-enclosed bodies and depleted inner content of S. aureus. Larger and irregular periplasmic space and deformed and scattered components of the cell envelope were observed in treated S. Enteritidis. The loss of 260-nm-absorbing material indicated that the disruptive action of the extract on cytoplasmic membrane was more pronounced in S. aureus than in S. Enteritidis treated cells. The UV and FTIR spectrophotometric analyses revealed diverse composition of C. versicolor extract and high content of total phenolics. Altogether, mushroom extracts could be used to develop nutraceuticals or drugs effective against pathogenic microorganisms.

A light microscopy and ultrastructural study of the testes of tortoise Testudo graeca (Testudinidae).

PubMed

Ibargüengoytía, N R; Pastor, L M; Pallares, J

1999-04-01

Adult males of Testudo graeca were used to preliminarily study the light microscopic morphology and the ultrastructure of the testes. Spermiogenesis has shown the presence of some interspecific variations among Chelonia, while the general features of the testes and spermatocytes are morphologically similar to other reptilians. The male reproductive state observed in the months analysed has shown spermatogenesis recrudescence in spring, a complete germinal series in autumn and testicular regression in winter. The observation of ultrastructural features, characteristic of steroidogenic activity, suggests a synchrony in tubular and interstitial compartments in T. graeca, with little steroidogenic activity in winter and active synthesis in spring and autumn. In conclusion, the results of this histological study suggest a probable asynchrony between the male and female reproductive cycle in this species and show synchrony in the steroidogenic activity of Sertoli and Leydig cells.

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

PubMed

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

1994-08-01

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

Ultrastructural Characteristics of the Testis, Spermatogenesis and Taxonomic Values of Sperm Morphology in Male Ruditapes philippinarum in Western Korea.

PubMed

Kim, Jin Hee; Chung, Jae Seung; Lee, Ki-Young

2013-06-01

Ultrastructural characteristics of the germ cells and accessory cells in testis during spermatogenesis and taxonomic values of mature sperm morphology of Ruditapes philippinarum were investigated by the transmission electron microscope and scanning electron microscope observations. The testis is the diffuse organ that consists of branching acini containing developing germ cells and accessory cells associated with spermatogenesis. The morphology of the spermatozoon is of the primitive type and is somewhat different to those of other bivalves. The morphologies of the sperm nucleus type and the acrosome shape of this species have a cylinderical type and a modified cone shape, respectively. As some ultrastructural characteristics of the acrosomal vesicle, the peripheral parts of two basal rings show electron opaque part, while the apex part of the acrosome shows electron lucent part. These characteristics of sperm belong to the family Veneridae in the subclass Heterodonta, unlike a characteristic of the subclass Pteriomorphia showing all part of the acrosome being composed of electron opaque part. In particular, a cylinder-like nucleus of the sperm is curved. The spermatozoon is approximately 48-51 μm in length, including a long acrosome (about 2.40 μm in length), a curved sperm nucleus (about 3.40 μm in length), and a tail flagellum. The axoneme of the sperm tail shows a 9+2 structure.

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.

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.

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

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

PubMed

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

2004-06-01

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

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.

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.

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.

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.

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.

Effect of elemental nano-selenium on semen quality, glutathione peroxidase activity, and testis ultrastructure in male Boer goats.

PubMed

Shi, Li-guang; Yang, Ru-jie; Yue, Wen-bin; Xun, Wen-juan; Zhang, Chun-xiang; Ren, You-she; Shi, Lei; Lei, Fu-lin

2010-04-01

The objective of this experiment is to study the effects of novel elemental nano-selenium in the diet on testicular ultrastructure, semen quality and GSH-Px activity in male goats. Forty-two 2-month-old bucks were offered a total mixed ration which had been supplemented with nano-Se (0.3mg/kg Se) or unsupplemented (the control group only received 0.06mg/kg Se-background), for a period of 12 weeks (from weaning to sexual maturity). Results showed that the testicular Se level, semen glutathione peroxidase and ATPase activity increased significantly in the nano-Se supplementation group compared with control (P<0.05). The semen quality (volume, density, motility and pH) was not affected by added Se in diets, however, the sperm abnormality rate of control bucks was significantly higher than Se supplemented bucks (P<0.05). The testes of 5 goats in each group were examined by transmission electron microscopy (TEM), and showed that in Se-deficient bucks the membrane was damaged, and showed the occurrence of abnormalities in the mitochondria of the midpiece of spermatozoa. In conclusion, selenium deficiency resulted in abnormal spermatozoal mitochondria, and supplementation with nano-Se enhanced the testis Se content, testicular and semen GSH-Px activity, protected the membrane system integrity and the tight arrayment of the midpiece of the mitochondria. Further studies are required to research the novel elemental nano-Se with characterization of bioavailability and toxicity in small ruminants. Copyright 2009 Elsevier B.V. All rights reserved.

Pagetoid reticulosis (Woringer-Kolopp disease). An ultrastructural and immunocytological study.

PubMed

Takahashi, H; Takahashi, K; Tanno, K; Iijima, S

1982-05-01

Histopathological, immunocytological and ultrastructural observations are reported in the first case of pagetoid reticulosis (Woringer-Kolopp disease) in Japan. The patient was a 61-year-old woman with multiple skin lesions running a chronic and apparently benign clinical course. Histology of the skin biopsies revealed typical pagetoid appearance of the epidermis due to intraepidermal infiltration of abnormal cells. Ultrastructural investigation showed that the intraepidermal abnormal cells were classified into mycosis fungoides cells, Sézary cells, lymphoblast-like cells, and large blastoid cells and that the mycosis fungoides cells were a major cell population. Intermediate or transitional cells were found between these cells and large blastoid cells were mostly situated in the basal cell layer. By the rosetting assays of the free cell suspensions prepared from the epidermis of the biopsied skin lesions, 93% of the suspended cells were positive for spontaneous rosette formation with sheep erythrocytes. The immunoperoxidase technique demonstrated no cytoplasmic immunoglobulins in almost all the intraepidermal abnormal cells. These results indicate that the intraepidermal abnormal cells are T-lymphocytes. Thus, it is concluded that the present case is a cutaneous T-cell lymphoma of low-grade malignancy showing a prominent epidermotropism. This case is the first description of the disease in Japan.

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.

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.

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.

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 effects of swimming exercise and supraphysiological doses of nandrolone decanoate on the testis in adult male rats: a transmission electron microscope study.

PubMed

Naraghi, M A; Abolhasani, F; Kashani, I; Anarkooli, I J; Hemadi, M; Azami, A; Barbarestani, M; Aitken, R J; Shokri, S

2010-08-01

Anabolic-androgenic steroids (AAS) are used in high doses by athletes to improve athletic ability, physical appearance, and muscle mass. Unfortunately, the abuse of these agents has significantly increased. It has been established that exercise and high doses of AAS may influence the hypothalamic-pituitary gonadal (H-P-G) axis, which can in turn affect the ultrastructure of the testes. However, the effect of the combination of exercise and high doses of AAS on the ultrastructure of the testes is not known. This study was undertaken in order to examine the combination effects of swimming exercise and supraphysiological doses of nandrolone decanoate on the ultrastructural changes in rat testes. Five groups of male Wistar strain albino rats were treated as follows for 8 weeks: solvent of nandrolone decanoate (peanut oil) as a vehicle (sham); nandrolone decanoate (ND) (10 mg/kg/week) - ND; exercise (1 h/day, 5 days a week) - exercise; ND (10 mg/kg/week) and exercise (1 h/day, 5 days a week) - ND-EX; and sedentary control without any injection or exercise - control. Ultrastructural changes in the rat testes were characterised by transmission electron microscopy. The number and size of Leydig cells were considerably decreased in the interstitial space in the experimental rats. The increased thickness and irregular wavy multilaminar appearance of basement membrane in the treated animals, especially in the ND-EX group, are associated with well developed myoid cells. Cytoplasm vacuolisation, vesicular-like crista of the mitochondria, numerous lipid droplets, and lysosome and phagolysosome in Sertoli cells were significantly observed in the experimental groups. Several apoptotic germ cells were considerably observed in the experimental rats (p ≤ 0.05). Exercise training seems to increase the extent of ultrastructural changes caused by supraphysiological doses of ND in rats, which in turn may affect fertility.

Ultrastructural study of the noninvolved urothelium of tumor-bearing patients after two years of intravesical interferon therapy.

PubMed

Stravoravdi, P; Natsis, K; Kirtsis, P; Retalis, G; Konstandinidis, E; Polyzonis, M

1996-01-01

Seventeen patients with transitional cell carcinoma of the urinary bladder were studied. Twelve patients did not have a recurrence 2 years after a transurethral resection (TUR) followed by interferon (IFN)-alpha 2b treatment. This observation led us to study the ultrastructural morphology of the noninvolved urothelium in 8 of the above 12 patients. All patients had a primary solitary grade I or II tumor. Topical therapy was started after TUR. Each patient received a total of 22 instillations of 50 MU IFN-alpha 2b in 12 months according to the standard procedure. After the first year, a repetitive dose of 50 MU IFN-alpha 2b was administered every 2 months for a period of 1 more year. At the end of therapy, certain ultrastructural modifications were observed indicating a partial restoration of the urothelium: the existence of asymmetric unit membrane, a well-developed Golgi apparatus and an increase of the filaments. The cells were joined to each other with well-developed tight junctions. Tubuloreticular inclusions were also observed. Prevention of recurrence by restoring the morphology of the noninvolved urothelium in response to IFN treatment deserves further examination.

Immunohistochemical and ultrastructural changes in rat fat tissue related to the local hCG injection.

PubMed

Tunç, E; Erdogan, D; Calgüner, E; Göktas, G; Elmas, Ç; Gözil, R; Bahçelioglu, M; Öktem, H

2013-11-01

Recently, it has been observed that weight loss is accelerated by human chorionic gonadotropin (hCG) hormone preparation used for hypothalamic dysfunction in obesity treatment in both sexes. hCG is also used for in vitro fertilization and in treatment of hypogonadotropic hypogonadism. Our aim was to observe the ultrastructural changes caused by local injections of hCG made for purpose of weight loss and to present them to inform those receiving such therapy. In our study, 10 obese female, 10 male obese, 10 non-obese female and 10 non-obese male rats were used. In each group, single dose of subcutaneous hCG injection has been applied to 7 rats for 5 weeks in 5 days of the week, and placebo has been applied to the remaining 3 rats. Following the injection, the tissues were evaluated morphologically, immunohistochemically and ultrastructurally. Leptin immunoreactivity was similar in all groups. When the adipose tissue samples were examined under electron microscope, they were observed to exhibit normal structure with organelles located around the nuclei and nucleoli, and no distinctive features were found among the groups. Administering hCG in addition to diet had no advantage on weight reduction in rats.

The sperm of Hylodinae species (Anura, Leptodactylidae): ultrastructural characteristics and their relevance to interspecific taxonomic relationships.

PubMed

Aguiar, O; Giaretta, A A; Recco-Pimentel, S M

2006-09-01

Hylodinae leptodactylids (sensu Lynch 1971) form a group of diurnal frogs, which is hypothesized on the basis of morphological traits to be the closest relatives of the dendrobatid frogs. Our study describes ultrastructural characteristics of sperm from three hylodine species (Hylodes phyllodes, Crossodactylus sp. n. and Megaelosia massarti) to reassess the intergeneric relationships within the Hylodinae, as well as the supposed relationship between the Hylodinae and Dendrobatidae. The ultrastructure of the sperm is very similar among the three species and is indicative of its conserved nature within the Hylodinae. The structure of the acrosomal complex was very similar to that of other leptodactylid species, to most of the remaining species included in the Bufonoidea lineage, and also to that observed in the dendrobatid species examined so far. Since such a structure has been considered a plesiomorphic trait, it contributes little to our understanding of the relationships between the Hylodinae and Dendrobatidae. The flagellar apparatus of Crossodactylus sp. n. is very similar to that of most leptodactylids. The sperm of Megaelosia massarti and Hylodes phyllodes display a distinctive condition in their axial and juxtaxonemal fibers. This distinctive flagellar condition expands the already known variability in sperm structure within the Leptodactylidae.

Functional Utrastructure of Genlisea (Lentibulariaceae) Digestive Hairs

PubMed Central

Płachno, Bartosz Jan; Kozieradzka-Kiszkurno, Małgorzata; Świątek, Piotr

2007-01-01

Background and Aims Digestive structures of carnivorous plants produce external digestive enzymes, and play the main role in absorption. In Lentibulariaceae, the ultrastructure of digestive hairs has been examined in some detail in Pinguicula and Utricularia, but the sessile digestive hairs of Genlisea have received very little attention so far. The aim of this study was to fill this gap by expanding their morphological, anatomical and histochemical characterization. Methods Several imaging techniques were used, including light, confocal and electron microscopy, to reveal the structure and function of the secretory hairs of Genlisea traps. This report demonstrates the application of cryo-SEM for fast imaging of whole, physically fixed plant secretory structures. Key Results and Conclusion The concentration of digestive hairs along vascular bundles in subgenus Genlisea is a primitive feature, indicating its basal position within the genus. Digestive hairs of Genlisea consist of three compartments with different ultrastructure and function. In subgenus Tayloria the terminal hair cells are transfer cells, but not in species of subgenus Genlisea. A digestive pool of viscous fluid occurs in Genlisea traps. In spite of their similar architecture, the digestive-absorptive hairs of Lentibulariaceae feature differences in morphology and ultrastructure. PMID:17550910

Dietary adaptions in the ultrastructure of dinosaur dentine.

PubMed

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

2016-12-01

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

Subconjunctival mitomycin C before pterygium excision: an ultrastructural study.

PubMed

Chang, Yi-Sheng; Chen, Wen-Chung; Tseng, Sung-Huei; Sze, Chun-I; Wu, Chao-Liang

2008-05-01

Subconjunctival injection of mitomycin C (MMC) before pterygium excision is a new adjunctive therapy to decrease pterygium recurrence. This study aimed to investigate the ultrastructural changes in pterygium after subconjunctival injection of MMC. Four patients underwent subconjunctival injection of 0.1 mL of 0.15 mg/mL MMC 1 month before pterygium excision, and 2 patients served as controls without preoperative MMC injection. The excised specimens of pterygium were examined under transmission electron microscopy. Epithelial cells of the treated pterygium remained unchanged. However, stromal fibroblasts were decreased in number, were oval rather than spindle-shaped, and had shrunken cytoplasmic processes; some were degenerating or apoptotic. Collagen and elastic fibers were decreased in density, disorganized, and degenerated. Capillary endothelial cells were thickened and swollen, with narrow or obliterated lumens. Axonal swelling and demyelination were observed. Subconjunctival injection of MMC inhibits fibrovascular activity in the pterygial stroma, leading to degeneration of the extracellular matrix and nerve axons. These ultrastructural changes are consistent with the clinical observation of reduced vascularity in the pterygium after MMC injection and verify the effectiveness of subconjunctival MMC injection 1 month before pterygium excision in decreasing the risk of pterygium recurrence.

Ultrastructural changes in the mycelium of Hericium erinaceum (Bull.; Fr.) Pers. under selenium-induced oxidative stress.

PubMed

Ślusarczyk, Joanna; Kuraś, Mieczysław; Malinowska, Eliza; Skalicka-Woźniak, Krystyna; Głowniak, Kazimierz

2014-10-01

In this study we examined the influence of various forms of selenium (organic and inorganic) on the vivacity of Hericium erinaceum mycelium and structural changes and ultrastructure occurring during its development in submerged culture. The mycelium was grown on sodium selenite (Na₂SeO₃), Selol (with 20 and 50 g kg⁻¹ Se, respectively) and a mixture of Na₂SeO₃ and Selol. Samples of the mycelium were collected on day 3 and day 24 of the incubation and viewed under an electron microscope. Selol at concentration 20 g kg⁻¹ did not cause any damage to the cell ultrastructure, but it contributed to the thickening of the cell wall, which implied an influence on polysaccharide production. In the other cases, degradation changes appeared in the protoplasm and the thickness of the cell wall did not increase. The nature of the effect exerted by various sources of selenium in the culture medium on the formation of polysaccharides probably results from the differences in their chemical composition and differences in the toxicity of these compounds towards the cells, but is also connected with the decomposition of the wall surrounding degraded fungal cells. © 2014 Society of Chemical Industry.

Encephalitozoonosis in two inland bearded dragons (Pogona vitticeps).

PubMed

Richter, B; Csokai, J; Graner, I; Eisenberg, T; Pantchev, N; Eskens, H U; Nedorost, N

2013-02-01

Microsporidiosis is reported rarely in reptiles. Sporadic multisystemic granulomatous disease of captive bearded dragons (Pogona vitticeps) has been associated with microsporidia showing Encephalitozoon-like morphology. Two such cases are described herein. Both animals displayed clinical signs suggestive of renal failure. Necropsy examination revealed granulomatous lesions in the liver and adrenal area in both animals, and in several other organs in one animal. The lesions were associated with intracellular protozoa consistent with microsporidia. Ultrastructural examination of the organisms revealed morphology similar to Encephalitozoon spp. Immunohistochemistry and chromogenic in-situ hybridization for Encephalitozoon cuniculi were positive in both animals. Nucleotide sequencing of the partial small subunit ribosomal RNA gene and the complete internal transcribed spacer (ITS) region revealed high similarity with published E. cuniculi sequences in both animals. However, the ITS region showed a GTTT-repeat pattern distinct from mammalian E. cuniculi strains. This may be a novel E. cuniculi strain associated with multisystemic granulomatous disease in bearded dragons. Copyright © 2012 Elsevier Ltd. All rights reserved.

Ultrastructural changes of the capillaries of the cat iris in experimental neuroparalytic keratitis.

PubMed

Saari, M; Huhtala, A; Johansson, G

1975-01-01

In order to study the morphological basis of the increased permeability of the capillaries of the iris in neuroparalytic keratitis the ophthalmic division of the trigeminal nerve in the cat was denervated using a stereotactic method. The homolateral iris was studied by electron microscopy three days after denervation. Abnormally large pinocytotic vacuoles were observed in the endothelial cells of the iris capillaries and the intercellular junctions of the endothelial cells showed widened inter-cellular space and macula occludens. These ultrastructural changes may explain the protein leakage into the anterior chamber in neuroparalytic keratitis.

Improved Serial Sectioning Techniques for Correlative Light-Electron Microscopy Mapping of Human Langerhans Islets

PubMed Central

Saitoh, Sei; Ohno, Nobuhiko; Saitoh, Yurika; Terada, Nobuo; Shimo, Satoshi; Aida, Kaoru; Fujii, Hideki; Kobayashi, Tetsuro; Ohno, Shinichi

2018-01-01

Combined analysis of immunostaining for various biological molecules coupled with investigations of ultrastructural features of individual cells is a powerful approach for studies of cellular functions in normal and pathological conditions. However, weak antigenicity of tissues fixed by conventional methods poses a problem for immunoassays. This study introduces a method of correlative light and electron microscopy imaging of the same endocrine cells of compact and diffuse islets from human pancreatic tissue specimens. The method utilizes serial sections obtained from Epon-embedded specimens fixed with glutaraldehyde and osmium tetroxide. Double-immunofluorescence staining of thick Epon sections for endocrine hormones (insulin and glucagon) and regenerating islet-derived gene 1 α (REG1α) was performed following the removal of Epoxy resin with sodium ethoxide, antigen retrieval by autoclaving, and de-osmification treatment with hydrogen peroxide. The immunofluorescence images of endocrine cells were superimposed with the electron microscopy images of the same cells obtained from serial ultrathin sections. Immunofluorescence images showed well-preserved secretory granules in endocrine cells, whereas electron microscopy observations demonstrated corresponding secretory granules and intracellular organelles in the same cells. In conclusion, the correlative imaging approach developed by us may be useful for examining ultrastructural features in combination with immunolocalisation of endocrine hormones in the same human pancreatic islets. PMID:29622846

Some ultrastructural characteristics of the renal artery and abdominal aorta in the rat.

PubMed Central

Osborne-Pellegrin, M J

1978-01-01

The rat renal artery and abdominal aorta have been studied by light and electron microscopy. In rats of 200 g body weight the extracellular space in aortic media ranges between 50-60% and that of the distal renal artery between 15-25%. The surface to volume ratio of aortic smooth muscle cells is 2.7 micron2/micron3 compared to 1.6 micron2/micron3 in the distal renal artery. Dense bodies are rare in aortic smooth muscle cells but are abundant in those of the distal renal artery. Other ultrastructural details of the smooth muscle cells are similar in the two types of artery. Cell-to-cell contacts consist of simple apposition of plasm membranes and their number is proportional to the total length of cell membrane profile. Mitochondria represent 7-8% of the cell volume in both arteries. The proximal renal artery shows structural characteristics which are intermediate between those of the aorta and distal renal artery. In all renal arteries examined, bands of longitudinal smooth muscle are present in the adventitia, principally at branch points. In older rats, regions of discontinuity of the internal elastic lamina have been observed. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:640965

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.

Contact urticaria due to the common stinging nettle (Urtica dioica)--histological, ultrastructural and pharmacological studies.

PubMed

Oliver, F; Amon, E U; Breathnach, A; Francis, D M; Sarathchandra, P; Black, A K; Greaves, M W

1991-01-01

A frequent cause of contact urticaria is skin exposure to the common stinging nettle (Urtica dioica). The urticaria is accompanied by a stinging sensation lasting longer than 12 h. Little is known of the cellular and molecular mechanism of stinging-nettle urticaria. After preliminary pharmacological analysis of pro-inflammatory activity in nettle stings, the cellular response of mononuclear cells, polymorphonuclear cells and mast cells was examined in six people 5 min and 12 h after nettle contact. Only mast cell numbers were significantly increased at 12 h. Ultrastructurally, some mast cells showed evidence of degranulation at 5 min and 12 h. At 12 h mast cells were closely associated with dermal dendritic cells and lymphocytes suggesting a functional unit. The mean histamine and serotonin contents of a nettle hair were found to be 6.1 ng and 33.25 pg, respectively. Nettle-sting extracts did not demonstrate histamine release from dispersed rat mast cells in vitro. These results suggest that part of the immediate reaction to nettle stings is due to histamine introduced by the nettle. However, the persistence of the stinging sensation might suggest the presence of substances in nettle fluid directly toxic to nerves or capable of secondary release of other mediators.

Insight into Bone-Derived Biological Apatite: Ultrastructure and Effect of Thermal Treatment

PubMed Central

Liu, Quan; Pan, Haobo; Chen, Zhuofan; Matinlinna, Jukka Pekka

2015-01-01

Objectives. This study aims at examining the ultrastructure of bone-derived biological apatite (BAp) from a series of small vertebrates and the effect of thermal treatment on its physiochemical properties. Materials and Methods. Femurs/fin rays and vertebral bodies of 5 kinds of small vertebrates were firstly analyzed with X-ray microtomography. Subsequently, BAp was obtained with thermal treatment and low power plasma ashing, respectively. The properties of BAp, including morphology, functional groups, and crystal characteristics were then analyzed. Results. The bones of grouper and hairtail were mainly composed of condensed bone. Spongy bone showed different distribution in the bones from frog, rat, and pigeon. No significant difference was found in bone mineral density of condensed bone and trabecular thickness of spongy bone. Only platelet-like crystals were observed for BAp obtained by plasma ashing, while rod-like and irregular crystals were both harvested from the bones treated by sintering. A much higher degree of crystallinity and larger crystal size but a lower content of carbonate were detected in the latter. Conclusion. Platelet-like BAp is the common inorganic component of vertebrate bones. BAp distributing in condensed and spongy bone may exhibit differing thermal reactivity. Thermal treatment may alter BAp's in vivo structure and composition. PMID:25695088

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.

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

Pathology, immunohistochemistry, and ultrastructural findings associated with neurological sarcocystosis in cattle

USDA-ARS?s Scientific Manuscript database

The case of neurological sarcocystosis in a nine months old bull calf that died in 1982 was restudied. The bull was suspected to have rabies. Therefore, only brain was examined histologically. Thirty four years later, we restudied sections from paraffin-embedded blocks of brain. Numerous schizonts a...

Hemocytes of Rhipicephalus sanguineus (Acari: Ixodidae): Characterization, Population Abundance, and Ultrastructural Changes Following Challenge with Leishmania infantum.

PubMed

Feitosa, A P S; Alves, L C; Chaves, M M; Veras, D L; Silva, E M; Aliança, A S S; França, I R S; Gonçalves, G G A; Lima-Filho, J L; Brayner, F A

2015-11-01

Few studies have examined the cellular immune response of ticks, and further research on the characterization of the hemocytes of ticks is required, particularly on those of Rhipicephalus sanguineus (Latreille) because of the medical and veterinary importance of this tick. The aims of this study were to characterize the morphology and the ultrastructure of the different types of hemocytes of adult R. sanguineus and to determine the population abundance and the ultrastructural changes in the hemocytes of ticks infected with Leishmania infantum. The hemocytes were characterized through light and transmission electron microscopy. Within the variability of circulating cells in the hemolymph of adult R. sanguineus, five cell types were identified, which were the prohemocytes, plasmatocytes, granulocytes, spherulocytes, and adipohemocytes. The prohemocytes were the smallest cells found in the hemolymph. The plasmatocytes had polymorphic morphology with vesicles and cytoplasmic projections. The granulocytes had an elliptical shape with the cytoplasm filled with granules of different sizes and electrodensities. The spherulocytes were characterized by several spherules of uniform shapes and sizes that filled the entire cytoplasm, whereas the adipohemocytes had an irregular shape with multiple lipid inclusions that occupied almost the entire cytoplasmic space. The total counts of the hemocyte population increased in the group that was infected with L. infantum. Among the different cell types, the numbers increased and the ultrastructural changes occurred in the granulocytes and the plasmatocytes in the infected group of ticks. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Ultra-structural hair alterations in Friedreich's ataxia: A scanning electron microscopic investigation.

PubMed

Turkmenoglu, F Pinar; Kasirga, U Baran; Celik, H Hamdi

2015-08-01

Friedreich's ataxia (FRDA) is an autosomal recessive inherited disorder involving progressive damage to the central and peripheral nervous systems and cardiomyopathy. FRDA is caused by the silencing of the FXN gene and reduced levels of the encoded protein, frataxin. Frataxin is a mitochondrial protein that functions primarily in iron-sulfur cluster synthesis. Skin disorders including hair abnormalities have previously been reported in patients with mitochondrial disorders. However, to our knowledge, ultra-structural hair alterations in FRDA were not demonstrated. The purpose of this study was to determine ultra-structural alterations in the hairs of FRDA patients as well as carriers. Hair specimen from four patients, who are in different stages of the disease, and two carriers were examined by scanning electron microscope. Thin and weak hair follicles with absence of homogeneities on the cuticular surface, local damages of the cuticular layer, cuticular fractures were detected in both carriers and patients, but these alterations were much more prominent in the hair follicles of patients. In addition, erosions on the surface of the cuticle and local deep cavities just under the cuticular level were observed only in patients. Indistinct cuticular pattern, pores on the cuticular surface, and presence of concavities on the hair follicle were also detected in patients in later stages of the disease. According to our results, progression of the disease increased the alterations on hair structure. We suggest that ultra-structural alterations observed in hair samples might be due to oxidative stress caused by deficient frataxin expression in mitochondria. © 2015 Wiley Periodicals, Inc.

Edaravone protects rats against oxidative stress and apoptosis in experimentally induced myocardial infarction: Biochemical and ultrastructural evidence.

PubMed

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

2015-01-01

The present study was designed to evaluate the cardioprotective potential of edaravone on oxidative stress, anti-apoptotic, anti-inflammatory and ultrastructure findings in isoproterenol (ISO) induced myocardial infarction (MI) in rats. Rats were pretreated with edaravone (1, 3, 10 mg/kg body weight-1 day-1) intraperitoneally. MI was induced by subcutaneous administration of ISO (85 mg/kg body weight-1) at two doses with 24h interval. ISO treated rats showed significant increase in the levels of thiobarbituric acid reactive substances (TBARS) and decreased levels of reduced glutathione, glutathione perdoxidase, glutathione reductase and glutathione-S- transferase in the cardiac tissues. Moreover, significant increase in the levels of lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB), C--reactive protein and caspase-3 activity was observed in ISO treated group. Pretreatment of ISO intoxicated rats with edaravone showed significant decrease in the level of TBARS, increased activities of antioxidant enzymes and significantly decreased levels of LDH and CK-MB. Moreover, results also showed decreased C-reactive protein level, caspase-3 activity and maintained ultrastructure of the myocardial cells. Our study suggests that edaravone possess strong cardioprotective potential. Edaravone may have exhibited cardioprotective effects by restoring antioxidant defense mechanism, maintaining integrity of myocardial cell membrane, reducing apoptosis and inflammation against ISO induced MI and associated oxidative stress.

Ultrastructural Changes and Death of Leishmania infantum Promastigotes Induced by Morinda citrifolia Linn. Fruit (Noni) Juice Treatment

PubMed Central

Almeida-Souza, Fernando; Taniwaki, Noemi Nosomi; Amaral, Ana Cláudia Fernandes; de Souza, Celeste da Silva Freitas; Calabrese, Kátia da Silva; Abreu-Silva, Ana Lúcia

2016-01-01

The search for new treatments against leishmaniasis has increased due to high frequency of drug resistance registered in endemics areas, side effects, and complications caused by coinfection with HIV. Morinda citrifolia Linn., commonly known as Noni, has a rich chemical composition and various therapeutic effects have been described in the literature. Studies have shown the leishmanicidal activity of M. citrifolia; however, its action on the parasite has not yet been elucidated. In this work, we analyzed leishmanicidal activity and ultrastructural changes in Leishmania infantum promastigotes caused by M. citrifolia fruit juice treatment. M. citrifolia fruit extract showed a yield of 6.31% and high performance liquid chromatography identified phenolic and aromatic compounds as the major constituents. IC50 values were 260.5 µg/mL for promastigotes and 201.3 µg/mL for intracellular amastigotes of L. infantum treated with M. citrifolia. Cytotoxicity assay with J774.G8 macrophages showed that M. citrifolia fruit juice was not toxic up to 2 mg/mL. Transmission electron microscopy showed cytoplasmic vacuolization, lipid inclusion, increased exocytosis activity, and autophagosome-like vesicles in L. infantum promastigotes treated with M. citrifolia fruit juice. M. citrifolia fruit juice was active against L. infantum in the in vitro model used here causing ultrastructural changes and has a future potential for treatment against leishmaniasis. PMID:27313649

Ultrastructural Changes and Death of Leishmania infantum Promastigotes Induced by Morinda citrifolia Linn. Fruit (Noni) Juice Treatment.

PubMed

Almeida-Souza, Fernando; Taniwaki, Noemi Nosomi; Amaral, Ana Cláudia Fernandes; de Souza, Celeste da Silva Freitas; Calabrese, Kátia da Silva; Abreu-Silva, Ana Lúcia

2016-01-01

The search for new treatments against leishmaniasis has increased due to high frequency of drug resistance registered in endemics areas, side effects, and complications caused by coinfection with HIV. Morinda citrifolia Linn., commonly known as Noni, has a rich chemical composition and various therapeutic effects have been described in the literature. Studies have shown the leishmanicidal activity of M. citrifolia; however, its action on the parasite has not yet been elucidated. In this work, we analyzed leishmanicidal activity and ultrastructural changes in Leishmania infantum promastigotes caused by M. citrifolia fruit juice treatment. M. citrifolia fruit extract showed a yield of 6.31% and high performance liquid chromatography identified phenolic and aromatic compounds as the major constituents. IC50 values were 260.5 µg/mL for promastigotes and 201.3 µg/mL for intracellular amastigotes of L. infantum treated with M. citrifolia. Cytotoxicity assay with J774.G8 macrophages showed that M. citrifolia fruit juice was not toxic up to 2 mg/mL. Transmission electron microscopy showed cytoplasmic vacuolization, lipid inclusion, increased exocytosis activity, and autophagosome-like vesicles in L. infantum promastigotes treated with M. citrifolia fruit juice. M. citrifolia fruit juice was active against L. infantum in the in vitro model used here causing ultrastructural changes and has a future potential for treatment against leishmaniasis.

Congenital renal rhabdoid tumor with placental metastases: immunohistochemistry, cytogenetic, and ultrastructural findings.

PubMed

de Tar, Michael; Sanford Biggerstaff, Julie

2006-01-01

Malignant congenital tumors of fetal origin are rare lesions, the most common type being congenital neuroblastoma. Although prenatal diagnosis is possible in large tumors, occasionally the tumor will be diagnosed first by its metastatic involvement of the placenta. Placental metastases can reflect either maternal or fetal primary sites, and each has relatively specific patterns of placental involvement. We describe the clinical and pathologic features of a widely metastatic congenital renal rhabdoid tumor with its placental and autopsy findings, and include the immunohistochemical, cytogenetic, and ultrastructural features. The pathologic features of the placenta in congenital renal rhabdoid tumor with placental metastasis have not been previously described. The examination of the placenta in this case led to the initial diagnosis and obviated the need for additional diagnostic procedures.

Serous cutaneous glands in new world hylid frogs: an ultrastructural study on skin poisons confirms phylogenetic relationships between Osteopilus septentrionalis and Phrynohyas venulosa.

PubMed

Delfino, Giovanni; Brizzi, Rossana; Nosi, Daniele; Terreni, Alessandro

2002-08-01

Transmission electron microscope investigations of the serous (poison) skin glands in the New World tree frogs Osteopilus septentrionalis and Phrynohyas venulosa revealed that they produce granules with closely similar substructures, namely, a dense cortex and pale medulla. In both species these features, that contrast the complex, sometimes repeating patterns described in other hylid frogs, derive from similar secretory and maturational processes starting from the Golgi phase of poison biosynthesis. Observations on secretory discharge showed that the two species share common release mechanisms, based on bulk discharge (holocrine) processes. Our data provide novel evidence of the extensive ultrastructural polymorphism of serous skin products in Hylidae and agree with phylogenies that regard this family as polyphyletic in origin. Assuming that ultrastructural features of cutaneous poison biosynthesis and maturation are adequate clues for tracking anuran phylogeny, the present findings also support a close relationship between Osteopilus and Phrynohyas taxa as previously suggested by osteological evidence. Copyright 2002 Wiley-Liss, Inc.

The influenza fingerprints: NS1 and M1 proteins contribute to specific host cell ultrastructure signatures upon infection by different influenza A viruses

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

Terrier, Olivier; Moules, Vincent; Carron, Coralie

Influenza A are nuclear replicating viruses which hijack host machineries in order to achieve optimal infection. Numerous functional virus-host interactions have now been characterized, but little information has been gathered concerning their link to the virally induced remodeling of the host cellular architecture. In this study, we infected cells with several human and avian influenza viruses and we have analyzed their ultrastructural modifications by using electron and confocal microscopy. We discovered that infections lead to a major and systematic disruption of nucleoli and the formation of a large number of diverse viral structures showing specificity that depended on the subtypemore » origin and genomic composition of viruses. We identified NS1 and M1 proteins as the main actors in the remodeling of the host ultra-structure and our results suggest that each influenza A virus strain could be associated with a specific cellular fingerprint, possibly correlated to the functional properties of their viral components.« less

Ultrastructural and biochemical investigations of protein mobilization of Mucuna pruriens (L.) DC. cotyledons and embryo axis.

PubMed

Muccifora, Simonetta; Guerranti, Roberto; Muzzi, Chiara; Hope-Onyekwere, Nnadozies S; Pagani, Roberto; Leoncini, Roberto; Bellani, Lorenza M

2010-03-01

The mobilization of storage reserves, with particular emphasis on storage proteins of Mucuna pruriens (L.) DC., cotyledons, and embryo was investigated from the ultrastructural and biochemical points of view. Proteins and starch were the two main storage substances in cotyledons, and proteins and lipids were the main ones in the embryo. Embryo protein bodies were smaller and fewer in number than those of cotyledons. Structural and ultrastructural data determined between 24 and 48 h after imbibition and between 48 and 72 h after imbibition, the end of significant embryo and cotyledon protein mobilization, respectively, indicating more precocious storage protein mobilization in the axis than cotyledons. Moreover, storage protein mobilization in embryo and cotyledons occurred before the end of germination. Water soluble proteins were separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis, producing 29 bands with molecular weights from 14 to 90 KDa. Embryo extract contained more proteins than cotyledon extract, contained seven characteristic bands, and showed a higher variability of the optical density trend than cotyledon.

THE CELLULAR STRUCTURE OF LYMPHOMYELOID TISSUES IN CHIMAERA MONSTROSA (PISCES, HOLOCEPHALI).

PubMed

Mattisson, Artur; Fänge, Ragnar

1986-12-01

The ultrastructure of the main lymphomyeloid organs of the holocephalan fish, Chimaera monstrosa, is presented. The thymus is well developed even in adults. It is densely packed with small and large lymphocytes, the former predominating. The ultrastructure of C. monstrosa's lymphocytes is similar to that of mammalian ones. The lymphocytes show intimate connections with large epithelial reticulocytes, which infiltrate the cytoplasm of the lymphocytes with long processes. The lymphomyeloid tissues around the orbit are mainly granulocytopoietic. Two types of granulocytes occur: eosinophilic and heterophilic. The latter is found in excess. The granulocytes are ultrastructurally similar to those of elasmobranchs such as Etmopterus spinax and have similar characteristic granules. In addition to granulocytes in various stages, lymphocytes, plasma cells, blast cells, and solitary macrophages are scattered throughout the tissue. The suprapalatal region also has a similar supply and variety of cells, but most heterophilic granulocytes have modified granules. In the spleen, erythrocytes in different developmental stages are common. This confirms earlier studies which suggested that the spleen functions primarily as an erythrocytopoietic organ.

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.

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

PubMed

Mahmoud, Y I; Hegazy, H G

2016-01-01

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

The Antibacterial Activity of Coriolus versicolor Methanol Extract and Its Effect on Ultrastructural Changes of Staphylococcus aureus and Salmonella Enteritidis

PubMed Central

Matijašević, Danka; Pantić, Milena; Rašković, Božidar; Pavlović, Vladimir; Duvnjak, Dunja; Sknepnek, Aleksandra; Nikšić, Miomir

2016-01-01

The antibacterial activity of methanol extract obtained from fruiting body of industrially grown basidiomycete Coriolus versicolor was examined. The Minimum Inhibitory Concentration (MIC) values against various bacteria ranged from 0.625 to 20 mg mL-1. C. versicolor expressed bactericidal activity against both Gram-positive and Gram-negative bacteria. The growth curves of Staphylococcus aureus and Salmonella enterica serovar Enteritidis, measured at 630 nm, and confirmed with macrodilution method showed that the obtained extract could inhibit the growth of tested bacteria. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and the loss of 260-nm-absorbing material were used to examine the ultrastructural changes in bacteria induced by the extract. When S. aureus was exposed to the MIC of C. versicolor, elongated and malformed cells were observed by SEM, while S. Enteritidis treated cells appeared shorter and aggregated with ruptured cell walls. TEM revealed the formation of non-membrane-enclosed bodies and depleted inner content of S. aureus. Larger and irregular periplasmic space and deformed and scattered components of the cell envelope were observed in treated S. Enteritidis. The loss of 260-nm-absorbing material indicated that the disruptive action of the extract on cytoplasmic membrane was more pronounced in S. aureus than in S. Enteritidis treated cells. The UV and FTIR spectrophotometric analyses revealed diverse composition of C. versicolor extract and high content of total phenolics. Altogether, mushroom extracts could be used to develop nutraceuticals or drugs effective against pathogenic microorganisms. PMID:27540376

The oxidative damage and disbalance of calcium homeostasis in brain of chicken induced by selenium deficiency.

PubMed

Xu, Shi-Wen; Yao, Hai-Dong; Zhang, Jian; Zhang, Zi-Wei; Wang, Jin-Tao; Zhang, Jiu-Li; Jiang, Zhi-Hui

2013-02-01

Dietary selenium (Se) deficiency can influence the function of the brain. Our objective was to investigate the effects of Se deficiency on oxidative damage and calcium (Ca) homeostasis in brain of chicken. In the present study, 1-day-old chickens were fed either a commercial diet (as control group) with 0.15 mg/kg Se or a Se-deficient diet (as L group) with 0.033 mg/kg Se for 75 days. Then, brain injury biomarkers were examined, including histological analysis, ultrastructure assay, and apoptosis assay. We also examined the effect of Se deficiency on the Se-containing antioxidative enzyme glutathione peroxidase (GSH-Px), the level of glutathione (GSH), and the Ca homeostasis in brain of chicken. The results showed that the levels of Se and GSH and activity of GSH-Px are seriously reduced by 33.8-96 % (P < 0.001), 24.51-27.84 % (P < 0.001), and 20.70-64.24 % (P < 0.01), respectively. In the present study, we also perform histological analysis and ultrastructure assay and find that Se deficiency caused disorganized histological structure, damage to the mitochondria, fusion of nuclear membrane and nucleus shrinkage, higher apoptosis rate (P < 0.001), and increase of Ca homeostasis (P < 0.05 or P < 0.01 or P < 0.001) in the brain of chicken. In conclusion, the results demonstrated that Se deficiency induced oxidative damage and disbalance of Ca homeostasis in the brain of chicken. Similar to mammals, chickens brain is also extremely susceptible to oxidative damage and selenium deficiency.

Germacranolide-type sesquiterpene lactones from Smallanthus sonchifolius with promising activity against Leishmania mexicana and Trypanosoma cruzi.

PubMed

Ulloa, Jerónimo L; Spina, Renata; Casasco, Agustina; Petray, Patricia B; Martino, Virginia; Sosa, Miguel A; Frank, Fernanda M; Muschietti, Liliana V

2017-11-13

Leishmaniasis and Chagas disease are life-threatening illnesses caused by the protozoan parasites Leishmania spp. and Trypanosoma cruzi, respectively. They are known as "neglected diseases" due to the lack of effective drug treatments and the scarcity of research work devoted to them. Therefore, the development of novel and effective drugs is an important and urgent need. Natural products are an important source of bioactive molecules for the development of new drugs. In this study, we evaluated the activity of enhydrin, uvedalin and polymatin B, three sesquiterpene lactones (STLs) isolated from Smallanthus sonchifolius, on Leishmania mexicana (MNYC/BZ/62/M) and Trypanosoma cruzi (Dm28c). In addition, the in vivo trypanocidal activity of enhydrin and uvedalin and the effects of these STLs on parasites' ultrastructure were evaluated. The inhibitory effect of the three STLs on the growth of L. mexicana amastigotes and promastigotes as well as T. cruzi epimastigotes was evaluated in vitro. The changes produced by the STLs on the ultrastructure of parasites were examined by transmission electron microscopy (TEM). Enhydrin and uvedalin were also studied in a murine model of acute T. cruzi infection (RA strain). Serum activities of the hepatic enzymes alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase were used as biochemical markers of hepatotoxicity. The three compounds exhibited leishmanicidal activity on both parasite forms with IC 50 values of 0.42-0.54 μg/ml for promastigotes and 0.85-1.64 μg/ml for intracellular amastigotes. Similar results were observed on T. cruzi epimastigotes (IC 50 0.35-0.60 μg/ml). The TEM evaluation showed marked ultrastructural alterations, such as an intense vacuolization and mitochondrial swelling in both L. mexicana promastigotes and T. cruzi epimastigotes exposed to the STLs. In the in vivo study, enhydrin and uvedalin displayed a significant decrease in circulating parasites (50-71%) and no signs of hepatotoxicity were detected. Enhydrin, uvedalin and polymatin B possess significant leishmanicidal and trypanocidal activity on different parasite stages. These results show that these compounds may provide valuable leads for the development of new drugs against these neglected parasitic diseases.

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.

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.

Ultrastructural investigation of intact orbital implant surfaces using atomic force microscopy.

PubMed

Choi, Samjin; Lee, Seung Jun; Shin, Jae-Ho; Cheong, Youjin; Lee, Hui-Jae; Paek, Joo Hee; Kim, Jae Sik; Jin, Kyung-Hyun; Park, Hun-Kuk

2011-01-01

This study examined the surface nanostructures of three orbital implants: nonporous poly(methyl methacrylate) (PMMA), porous aluminum oxide and porous polyethylene. The morphological characteristics of the orbital implants surfaces were observed by atomic force microscopy (AFM). The AFM topography, phase shift and deflection images of the intact implant samples were obtained. The surface of the nonporous PMMA implant showed severe scratches and debris. The surface of the aluminum oxide implant showed a porous structure with varying densities and sizes. The PMMA implant showed nodule nanostructures, 215.56 ± 52.34 nm in size, and the aluminum oxide implant showed crystal structures, 730.22 ± 341.02 nm in size. The nonporous PMMA implant showed the lowest roughness compared with other implant biomaterials, followed by the porous aluminum oxide implant. The porous polyethylene implant showed the highest roughness and severe surface irregularities. Overall, the surface roughness of orbital implants might be associated with the rate of complications and cell adhesion. Copyright © 2011 Wiley Periodicals, Inc.

Effects of heavy metals on Cyanothece sp. CCY 0110 growth, extracellular polymeric substances (EPS) production, ultrastructure and protein profiles.

PubMed

Mota, Rita; Pereira, Sara B; Meazzini, Marianna; Fernandes, Rui; Santos, Arlete; Evans, Caroline A; De Philippis, Roberto; Wright, Phillip C; Tamagnini, Paula

2015-04-29

The effects of several heavy metals on the growth/survival, EPS production, ultrastructure and protein profiles of the highly efficient extracellular polymeric substances (EPS)-producer cyanobacterium Cyanothece sp. CCY 0110 were evaluated. Our results clearly show that each heavy metal affects the cells in a particular manner, triggering distinctive responses. Concerning chronic exposure, cells were more affected by Cu(2+) followed by Pb(2+), Cd(2+), and Li(+). The presence of metal leads to remarkable ultrastructural changes, mainly at the thylakoid level. The comparison of the proteomes (iTRAQ) allowed to follow the stress responses and to distinguish specific effects related to the time of exposure and/or the concentration of an essential (Cu(2+)) and a non-essential (Cd(2+)) metal. The majority of the proteins identified and with fold changes were associated with photosynthesis, CO2 fixation and carbohydrate metabolism, translation, and nitrogen and amino acid metabolism. Moreover, our results indicate that during chronic exposure to sub-lethal concentrations of Cu(2+), the cells tune down their metabolic rate to invest energy in the activation of detoxification mechanisms, which eventually result in a remarkable recovery. In contrast, the toxic effects of Cd(2+) are cumulative. Unexpectedly, the amount of released polysaccharides (RPS) was not enhanced by the presence of heavy metals. This work shows the holistic effects of different heavy metals on the cells of the highly efficient EPS-producer the cyanobacterium Cyanothece sp. CCY 0110. The growth/survival, EPS production, ultrastructure, protein profiles and stress response were evaluated. The knowledge generated by this study will contribute to the implementation of heavy-metal removal systems based on cyanobacteria EPS or their isolated polymers. Copyright © 2015. Published by Elsevier B.V.

Ultrastructural characterisation of the olfactory mucosa of the armadillo Dasypus hybridus (Dasypodidae, Xenarthra)

PubMed Central

FERRARI, C. C.; CARMANCHAHI, P. D.; ALDANA MARCOS, H. J.; AFFANNI, J. M.

2000-01-01

The ultrastructure of the olfactory mucosa of the armadillo Dasypus hybridus was studied. A comparison with the olfactory mucosa of another armadillo (Chaetophractus villosus) was made. The olfactory mucosa of D. hybridus shows many features which are similar to those of other mammals. Interestingly, it differs from the olfactory mucosa of the armadillo C. villosus. A suggestion is made that these differences may be due to differences in the digging habits of these species. In Dasypus, the supporting cells (SCs) showed dense vacuoles, multivesicular bodies and lysosome-like bodies probably related with the endocytotic system. The SCs show a dense network of SER presumably associated with xenobiotic mechanisms. The olfactory receptor neurons exhibit lysosome-like bodies and multivesicular bodies in their perikarya. These organelles suggest the presence of an endocytotic system. Duct cells of Bowman's glands exhibit secretory activities. Bowman's glands are compound-branched tubulo-acinar mixed glands with merocrine secretory mechanisms. PMID:10739023

Centriole Remodeling during Spermiogenesis in Drosophila.

PubMed

Khire, Atul; Jo, Kyoung H; Kong, Dong; Akhshi, Tara; Blachon, Stephanie; Cekic, Anthony R; Hynek, Sarah; Ha, Andrew; Loncarek, Jadranka; Mennella, Vito; Avidor-Reiss, Tomer

2016-12-05

The first cell of an animal (zygote) requires centrosomes that are assembled from paternally inherited centrioles and maternally inherited pericentriolar material (PCM) [1]. In some animals, sperm centrioles with typical ultrastructure are the origin of the first centrosomes in the zygote [2-4]. In other animals, however, sperm centrioles lose their proteins and are thought to be degenerated and non-functional during spermiogenesis [5, 6]. Here, we show that the two sperm centrioles (the giant centriole [GC] and the proximal centriole-like structure [PCL]) in Drosophila melanogaster are remodeled during spermiogenesis through protein enrichment and ultrastructure modification in parallel to previously described centrosomal reduction [7]. We found that the ultrastructure of the matured sperm (spermatozoa) centrioles is modified dramatically and that the PCL does not resemble a typical centriole. We also describe a new phenomenon of Poc1 enrichment of the atypical centrioles in the spermatozoa. Using various mutants, protein expression during spermiogenesis, and RNAi knockdown of paternal Poc1, we found that paternal Poc1 enrichment is essential for the formation of centrioles during spermiogenesis and for the formation of centrosomes after fertilization in the zygote. Altogether, these findings demonstrate that the sperm centrioles are remodeled both in their protein composition and in ultrastructure, yet they are functional and are essential for normal embryogenesis in Drosophila. Copyright © 2016 Elsevier Ltd. All rights reserved.

Responses of photosynthetic properties and chloroplast ultrastructure of Bryum argenteum from a desert biological soil crust to elevated ultraviolet-B radiation.

PubMed

Hui, Rong; Li, Xinrong; Chen, Cuiyun; Zhao, Xin; Jia, Rongliang; Liu, Lichao; Wei, Yongping

2013-04-01

Our understanding of plant responses to enhanced ultraviolet-B (UV-B) radiation has improved over recent decades. However, research on cryptogams is scarce and it remains controversial whether UV-B radiation causes changes in physiology related to photosynthesis. To investigate the effects of supplementary UV-B radiation on photosynthesis and chloroplast ultrastructure in Bryum argenteum Hedw., specimens were cultured for 10 days under four UV-B treatments (2.75, 3.08, 3.25 and 3.41 W m(-2) ), simulating depletion of 0% (control), 6%, 9% and 12% of stratospheric ozone at the latitude of Shapotou, a temperate desert area of northwest China. Analyses showed malondialdehyde content significantly increased, whereas chlorophyll (Chl) fluorescence parameters and Chl contents decreased with increased UV-B intensity. These results corresponded with changes in thylakoid protein complexes and chloroplast ultrastructure. Overall, enhanced UV-B radiation leads to significant decreases in photosynthetic function and serious destruction of the chloroplast ultrastructure of B. argenteum. The degree of negative influences increased with the intensity of UV-B radiation. These results may not only provide a potential mechanism for supplemental UV-B effects on photosynthesis of moss crust, but also establish a theoretical basis for further studies of adaptation and response mechanisms of desert ecosystems under future ozone depletion. Copyright © Physiologia Plantarum 2012.

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.

Comparative effectiveness of a clinostat and a slow-turning lateral vessel at mimicking the ultrastructural effects of microgravity in plant cells

NASA Technical Reports Server (NTRS)

Moore, R.

1990-01-01

The object of this research was to determine how effectively the actions of a clinostat and a fluid-filled, slow-turning lateral vessel (STLV) mimic the ultrastructural effects of microgravity in plant cells. We accomplished this by qualitatively and quantitatively comparing the ultrastructures of cells grown on clinostats and in an STLV with those of cells grown at 1 g and in microgravity aboard the Space Shuttle Columbia. Columella cells of Brassica perviridis seedlings grown in microgravity and in an STLV have similar structures. Both contain significantly more lipid bodies, less starch, and fewer dictyosomes than columella cells of seedlings grown at 1 g. Cells of seedlings grown on clinostats have significantly different ultrastructures from those grown in microgravity or in an STLV, indicating that clinostats do not mimic microgravity at the ultrastructural level. The similar structures of columella cells of seedlings grown in an STLV and in microgravity suggest that an STLV effectively mimics microgravity at the ultrastructural level.

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.

Effect of chitosan on hyphal growth and spore germination of plant pathogenic and biocontrol fungi.

PubMed

Palma-Guerrero, J; Jansson, H-B; Salinas, J; Lopez-Llorca, L V

2008-02-01

To investigate the toxic effect of chitosan on important root pathogenic and biocontrol fungi (nematophagous, entomopathogenic and mycoparasitic). We have used standard bioassays to investigate the effect of chitosan on colony growth and developed bioassays to test spore germination. The results showed that the root pathogenic and mycoparasitic fungi tested were more sensitive to chitosan than nematophagous and entomopathogenic fungi. Chitosanases (and perhaps related enzymes) are involved in the resistance to chitosan. Two fungi, one sensitive to chitosan, Fusarium oxysporum f. sp. radicis-lycopersici, and one less sensitive, Pochonia chlamydosporia, were selected for ultrastructural investigations. Transmission electron microscopy revealed differences in the ultrastructural alterations caused by chitosan in the spores of the plant pathogenic fungus and in those of the nematophagous fungus. Confocal laser microscopy showed that Rhodamine-labelled chitosan enters rapidly into conidia of both fungi, in an energy-dependent process. Nematophagous and entomopathogenic fungi are rather resistant to the toxic effect of chitosan. Resistance of nematophagous and entomopathogenic fungi to chitosan could be associated with their high extracellular chitosanolytic activity. Furthermore, ultrastructural damage is much more severe in the chitosan sensitive fungus. The results of this paper suggest that biocontrol fungi tested could be combined with chitosan for biological control of plant pathogens and pests.

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

Scanning electron microscopic study of a Ciloxan bottle blocked by ciprofloxacin crystals.

PubMed

John, T

2001-12-01

To report blockage of a commercially available ciprofloxacin bottle by white crystalline deposits. This study evaluated the ultrastructural features of the ciprofloxacin crystals. A patient underwent intensive topical treatment of an infectious corneal ulcer with commercially available ciprofloxacin 0.3% ophthalmic solution. During treatment, the patient was unable to obtain medication from the ciprofloxacin bottle and required a new prescription. Examination of the bottle revealed that about 50% of the medication remained, but compression of the bottle with any amount of force failed to deliver any medication. On closer examination, a white material partially filled the nozzle track of the bottle and was on the outer bottle near the nozzle and the inner surface of the bottle cap. These white crystalline deposits were evaluated by scanning electron microscopy. Plate-like, needle, cable and spaghetti-like crystals were found. The needle crystals formed multiple petaloid patterns. This is the first report of blockage of a commercially available ciprofloxacin 0.3% bottle by ciprofloxacin crystals and the inability to deliver medication from the bottle. Ultrastructural study of the white crystalline deposits revealed four types of ciprofloxacin crystals.

Effect of chocolate and Propolfenol on rabbit spermatogenesis and sperm quality following bacterial lipopolysaccharide treatment.

PubMed

Collodel, Giulia; Moretti, Elena; Del Vecchio, Maria Teresa; Biagi, Marco; Cardinali, Raffaella; Mazzi, Lucia; Brecchia, Gabriele; Maranesi, Margherita; Manca, Daniela; Castellini, Cesare

2014-08-01

The aims of the study were to evaluate the effects of chocolate and propolis-enriched diets on rabbit spermatogenesis, sperm motility, and ultrastructure following bacterial lipopolysaccharide (LPS) treatment. Thirty-two New Zealand White rabbits were divided into four groups. The LPS-Propolfenol(®) group received propolis (500 mg/kg/day) in their diet for 15 days, while the LPS-chocolate group was fed 70% cacao chocolate (1 g/1 kg/day) for the same period. Following the diet treatments, rabbits in the LPS-Propolfenol(®) and LPS-chocolate groups, and an LPS group received a single intraperitoneal dose of 50 μg/kg LPS, and the control group received only saline. Kinematic sperm traits were evaluated with a computer assisted sperm analyzer (CASA) system, and ultrastructural characteristics were examined by transmission electron microscopy (TEM). Testicular and epididymal tissues were observed by light microscopy and TEM and multiplex real time reverse transcriptase-polymerase chain reaction (RT-PCR) assay was used to detect and quantify toll-like receptor-4 (TLR-4) gene expression. The values of the analyzed semen parameters of rabbits treated with LPS-Propolfenol(®) and LPS-chocolate did not show any variations compared with the control group, but they were lower in rabbits treated only with LPS. Alterations observed in the testicular tissue of LPS treated-rabbits were not detected in specimens from the LPS-chocolate and LPS-Propolfenol(®) groups, which showed normal spermatogenesis. The TLR-4 mRNA expression was similar in controls, in LPS treated, and in LPS-chocolate groups, but it was significantly (p < 0.01) decreased in LPS-Propolfenol(®) rabbits. In conclusion, a chocolate and propolis-enriched diet showed a protective effect on the spermatogenetic process of buck rabbits following LPS treatment.

Ultrastructural analysis of oocytes of Rhipicephalus (Boophilus) annulatus during postengorgement period as a tool to evaluate the cytotoxic effects of amitraz and deltamethrin on the germinative cells.

PubMed

Sreelekha, Kanapadinchareveetil; Chandrasekhar, Leena; Kartha, Harikumar S; Ravindran, Reghu; Juliet, Sanis; Ajithkumar, Karapparambu G; Nair, Suresh N; Ghosh, Srikanta

2017-11-30

The present study utilizes the ultrastructural analysis of the fully engorged female Rhipicephalus (Boophilus) annulatus ticks, as a tool to evaluate the cytotoxic potential of deltamethrin and amitraz on the germinative cells. The ultrastructural analysis of the ovary of the normal (untreated) R (B.) annulatus revealed, oocytes in different stages of development, attached to the ovary wall by pedicel cells. The attachment site of oocyte to the pedicel cell was characterized by indentations of the plasma membrane. The oocyte was bound by three cell membranes viz., plasma membrane, chorion and basal lamina. The stages of oocytes were differentiated ultrastructurally based on the features of their outer membrane and the number and size of lipid and yolk droplets. Detailed day wise analysis of ultrastructural changes in the ovary during the post-engorgement period revealed the occurrence of the degenerative changes from day five onwards. These appeared first in the oocytes followed by the germinal epithelium. The ovary of ticks treated with methanol (control), revealed similar topographies as that of a normal ovary except for the presence of very few oocytes with ring shaped nucleoli. Ultrastructurally, treatment with deltamethrin produced more prominent and extensive morphological alterations when compared to amitraz. In the case of ticks treated with amitraz, the oocytes of stage IV and V showed wavy and disrupted outer boundaries along with the loss of integrity of the yolk droplets. Uneven nuclear membranes of stage II oocytes and cristolysis of mitochondria of mature oocytes were the other changes noticed. Ticks treated with deltamethrin revealed prominent modifications such as, detachment of the basal lamina, wrinkled boundary, inconsistent nuclear membrane, ring shaped nucleoli and chromatin clumping in the case of the early stage oocytes (I and II), whereas swelling and cristolysis of mitochondria were seen in mature oocytes. The study further indicated that, in addition to the previous proven neurotoxic effects, these compounds act directly on the ovary of tick. Copyright © 2017 Elsevier B.V. All rights reserved.

Preclinical and Clinical Studies of Unrelieved Aural Fullness following Intratympanic Gentamicin Injection in Patients with Intractable Ménière’s Disease

PubMed Central

Zhai, Feng; Zhang, Ru; Zhang, Ting; Steyger, Peter S.; Dai, Chun-Fu

2014-01-01

Objective To clarify whether gentamicin affects vestibular dark cells in guinea pigs and relieves patients of aural fullness with intractable Ménière’s disease following intratympanic administration. Materials and Methods Purified gentamicin-Texas Red (GTTR) was injected intratympanically in guinea pigs that were sacrificed at 1, 3, 7, 14 and 28 days. GTTR uptake was examined in hair cells, and transitional cells and dark cells in vestibular end-organs were examined. Specific attention was paid to its distribution in dark cells under confocal microscopy, and the ultrastructure of dark cells using electron microscopy, following intratympanic injection. Results Dark cells in the semicircular canals showed weak GTTR uptake at 1, 3, 7, 14 and 28 days after intratympanic injection, with no significant differences at various time points after injection. However, the adjacent transitional cells demonstrated intense GTTR uptake that was retained for at least 28 days. Ultrastructural studies demonstrated negligible characteristics associated with apoptosis or necrosis in these dark cells. The tight junctions between dark cells showed no signs of disruption at 7 or 28 days after injection. Conclusion Intratympanic gentamicin has little direct impact on vestibular dark cells. Clinical Application A modified low-dose titration intratympanic approach was used in 29 patients with intractable vertigo and the clinical outcomes were followed. Aural fullness following intratympanic gentamicin injection was not relieved based on our subjective scales, demonstrated by no statistically significant difference between preinjection (4.16 ± 3.08) and postinjection (3.58 ± 2.93; p > 0.05) aural fullness scores. Vertigo control was achieved in 88% of patients, with hearing deterioration identified in 16% of patients. Intratympanic gentamicin administration might not lead to relief of aural fullness in patients with intractable vertigo, although it can achieve a high vertigo control rate with some cochleotoxicity. PMID:24008307

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.

Effect of boric acid on antioxidant enzyme activity, lipid peroxidation, and ultrastructure of midgut and fat body of Galleria mellonella.

PubMed

Büyükgüzel, Ender; Büyükgüzel, Kemal; Snela, Milena; Erdem, Meltem; Radtke, Katarzyna; Ziemnicki, Kazimierz; Adamski, Zbigniew

2013-04-01

Boric acid is widely used as an insecticide, acaricide, herbicide, and fungicide and also during various industrial processings. Hence, numerous populations are subjects to this toxic compound. Its action on animals is still not fully known and understood. We examined the effect of boric acid on larvae of greater wax moth (Galleria mellonella). The chemical appeared to be toxic for larvae, usually in a concentration-dependent manner. Exposed groups revealed increased lipid peroxidation and altered activity of catalase, superoxide dismutase, glutathione S-transferase, and glutathione peroxidase. We also observed changes of ultrastructure, which were in tune with biochemical assays. We suggest that boric acid has a broad mode of action, which may affect exposed larvae, and even if sublethal, they may lead to disturbances within exposed populations.

[Human papilloma virus and cervical cancer. An historical review on the development of research on cancer of the cervix uteri in Venezuela].

PubMed

García-Tamayo, Jorge; Molina, Julia; Blasco-Olaetxea, Eduardo

2010-06-01

The history on the relationship of VPH infection and cervical cancer was examined. Findings were initially reported in Maracaibo(1971), later in Mexico(1973) and thereafter several studies on the ultrastructure and immunohistochemistry of VPH infection and its role on cervical cancer were described. The ultrastructural findings of viral particles of HPV and their proteins, as well as their role in the incorporation of the viral genome to the human cervical cells were also described. Glycoproteins on the surface of cervical cells were reviewed and their importance on HPV infection was related to p16, blood group antigens and early genetic changes in the cell cycle with loss of heterozigocity, all of which, stimulated by the high risk HPV infection lead to cervical cancer.

Papular dermatitis induced in guinea pigs by the biting midge Culicoides sonorensis (Diptera: Ceratopogonidae).

PubMed

O'Toole, D; Pérez de León, A A; Hearne, C; McHolland, L; Yun, L; Tabachnick, W

2003-01-01

Histological, ultrastructural, and virological examinations were performed on abdominal skin from guinea pigs after a blood meal by colony-bred biting midges, Culicoides sonorensis. Small, superficial, cutaneous, crateriform ulcers with necrosis of superficial dermis developed at feeding sites and healed within 24-48 hours. Animals developed nonpruritic erythematous papules 5 days after feeding that persisted until the study ended at 12 days after feeding. Papules corresponded histologically to foci of epidermal hyperplasia and superficial interstitial dermatitis with intraepidermal micropustules and scattered intraepidermal polykaryons. The principal ultrastructural changes were spongiosis in germinal epithelium and neutrophilic-histiocytic exocytosis. No viral agents or broken mouthparts were identified in lesions. The dermatitis may represent a host reaction to persisting insect salivary secretion and should be considered as an additional consequence of blood feeding in future studies involving biting midges.

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.

Differential responses of double petal and multi petal jasmine to shading: I. Photosynthetic characteristics and chloroplast ultrastructure.

PubMed

Deng, Yanming; Li, Congcong; Shao, Qingsong; Ye, Xiaoqing; She, Jianming

2012-06-01

A double petal (DP) and a multi petal (MP) type jasmine (Jasminum sambac Ait.) growth and flowering was known largely affected by different levels of irradiance. Here, our objective was to determine the effects of shade on photosynthesis related characteristics and chloroplast ultrastructure of these two types. In both types, net photosynthetic rate (Pn), stomatal conductance (g(s)) and transpiration rate increased with decreasing irradiance from 100% to 20%, while both maximum and variable fluorescence showed a steady increase, and photochemical and nonphotochemical quenching indexes declined. At each conducted time, chlorophyll a, b and carotenoids contents in DP type shaded leaves increased whereas those in MP type decreased at 5% irradiance (considered as extreme shade). The maximum photochemical efficiency of photosystem II of DP plants showed subtle changes but that of MP plants declined by shading thereafter 21 days of treatment. Observation of chloroplast ultrastructure showed its best development in the leaves of DP and MP types mostly from 50% to 20% irradiance (considered as weak and moderate shade, respectively). At each shade treatment, Pn, g(s) and water use efficiency of DP-jasmine were always higher than those of MP-jasmine, thus the shade tolerance ability of the former was higher than that of the latter. The results showed that full sunlight and 5% natural irradiance caused photoinhibition and light deficiency of jasmine plants respectively, and modulating chloroplast development by the more numbers of thylakoids and grana to contain more photosynthetic pigments is an important shade tolerance mechanism of DP type. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Ultrastructural and molecular confirmation of the development of Sarcocystis neurona tissue cysts in the central nervous system of southern sea otters (Enhydra lutris nereis).

PubMed

Miller, M A; Barr, B C; Nordhausen, R; James, E R; Magargal, S L; Murray, M; Conrad, P A; Toy-Choutka, S; Jessup, D A; Grigg, M E

2009-10-01

In 2004, three wild sea otters were diagnosed with putative Sarcocystis neurona-associated meningoencephalitis by histopathology and immunohistochemistry. Schizonts, free merozoites and tissue cysts were observed in the brains of all three infected animals. Tissue cysts walls from sea otter 1 (SO1) stained positively using anti-S. neurona polyclonal antiserum. However, positive staining does not preclude infection by closely related or cross-reactive tissue cyst-forming coccidian parasites. Two immature tissue cysts in the brain of SO1 were examined using transmission electron microscopy. Ultrastructural features included cyst walls with thin villous projections up to 1 microm long with tapered ends and a distinctive, electron-dense outer lining layer composed of linearly-arranged, semi-circular structures with a "hobnailed" surface contour. Small numbers of microtubules extended down through the villi into the underlying granular layer. Metrocytes were short and plump with an anterior apical complex, 22 sub-pellicular microtubules, numerous free ribosomes and no rhoptries. Some metrocytes appeared to be dividing, with two adjacent nuclear profiles. Collectively these ultrastructural features were compatible with developing protozoal cysts and were similar to prior descriptions of S. neurona tissue cysts. Panspecific 18S rDNA primers were utilized to identify protozoa infecting the brains of these otters and DNA amplification and additional sequencing at the ITS1 locus confirmed that all three otters were infected with S. neurona. No other Sarcocystis spp. were detected in the brains or skeletal muscles of these animals by immunohistochemistry or PCR. We believe this is the first ultrastructural and molecular confirmation of the development of S. neurona tissue cysts in the CNS of any animal.

Ultrastructural and molecular confirmation of the development of Sarcocystis neurona tissue cysts in the central nervous system of southern sea otters (Enhydra lutris nereis)

PubMed Central

Miller, M.A.; Barr, B.C.; Nordhausen, R.; James, E.R.; Magargal, S.L.; Murray, M.; Conrad, P.A.; Toy-Choutka, S.; Jessup, D.A.; Grigg, M.E.

2009-01-01

In 2004, three wild sea otters were diagnosed with putative Sarcocystis neurona-associated meningoencephalitis by histopathology and immunohistochemistry. Schizonts, free merozoites and tissue cysts were observed in the brains of all three infected animals. Tissue cysts from sea otter 1 (SO1) stained positively using anti-S. neurona polyclonal antiserum. However, positive staining does not preclude infection by closely related or cross-reactive tissue cyst-forming coccidian parasites. Two immature tissue cysts in the brain of SO1 were examined using transmission electron microscopy. Ultrastructural features included cyst walls with thin villous projections up to 1 μm long with tapered ends and a distinctive, electron-dense outer lining layer composed of linearly-arranged, semi-circular structures with a “hobnailed” surface contour. Small numbers of microtubules extended down through the villi into the underlying granular layer. Metrocytes were short and plump with an anterior apical complex, 22 subpellicular microtubules, numerous free ribosomes and no rhoptries. Some metrocytes appeared to be dividing, with two adjacent nuclear profiles. Collectively these ultrastructural features were compatible with developing protozoal cysts and were similar to prior descriptions of S. neurona tissue cysts. Panspecific 18S rDNA primers were utilized to identify protozoa infecting the brains of these otters and DNA amplification and additional sequencing at the ITS1 locus confirmed that all three otters were infected with S. neurona. No other Sarcocystis spp. were detected in the brains or skeletal muscles of these animals by immunohistochemistry or PCR. We believe this is the first ultrastructural and molecular confirmation of the development of S. neurona tissue cysts in the CNS of any animal. PMID:19527725

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

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

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.

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

PubMed

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

2017-09-15

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

[Effects of low intensity infra-red laser irradiation on ultrastructure and proliferation of liver cells in experimental hepatitis and cirrhosis].

PubMed

Baĭbekov, I M; Vorozheĭkin, V M; Artykov, Sh N

1992-04-01

With the aid of light, electron transmission and scanning electron microscopy and radioautography and stereometry, the influence of low-intensive laser irradiation (LILI) (infrared) was studied in normal rat liver and in experimental cirrhosis and hepatitis. It was revealed that arsenide-gallium laser irradiation causes the change of intracellular structure. These changes show the intensification on their specific function manifest in an increase of relative volume of intracellular structures. The changes of microvessels show the activation of microcirculation. The elevation of the index of the labelled nuclei testify to increased proliferation. The similar influences of LILI on the liver ultrastructure and proliferation in hepatitis and cirrhosis are accompanied by the reduction of the pathological changes of the liver--the hepatocytes oedema, granular, vacuolar and fatty dystrophy.

Localization and subcellular association of Grapevine Pinot Gris Virus in grapevine leaf tissues.

PubMed

Tarquini, Giulia; Ermacora, Paolo; Bianchi, Gian Luca; De Amicis, Francesca; Pagliari, Laura; Martini, Marta; Loschi, Alberto; Saldarelli, Pasquale; Loi, Nazia; Musetti, Rita

2018-05-01

Despite the increasing impact of Grapevine Pinot gris disease (GPG-disease) worldwide, etiology about this disorder is still uncertain. The presence of the putative causal agent, the Grapevine Pinot Gris Virus (GPGV), has been reported in symptomatic grapevines (presenting stunting, chlorotic mottling, and leaf deformation) as well as in symptom-free plants. Moreover, information on virus localization in grapevine tissues and virus-plant interactions at the cytological level is missing at all. Ultrastructural and cytochemical investigations were undertaken to detect virus particles and the associated cytopathic effects in field-grown grapevine showing different symptom severity. Asymptomatic greenhouse-grown grapevines, which tested negative for GPGV by real time RT-PCR, were sampled as controls. Multiplex real-time RT-PCR and ELISA tests excluded the presence of viruses included in the Italian certification program both in field-grown and greenhouse-grown grapevines. Conversely, evidence was found for ubiquitous presence of Grapevine Rupestris Stem Pitting-associated Virus (GRSPaV), Hop Stunt Viroid (HSVd), and Grapevine Yellow Speckle Viroid 1 (GYSVd-1) in both plant groups. Moreover, in every field-grown grapevine, GPGV was detected by real-time RT-PCR. Ultrastructural observations and immunogold labelling assays showed filamentous flexuous viruses in the bundle sheath cells, often located inside membrane-bound organelles. No cytological differences were observed among field-grown grapevine samples showing different symptom severity. GPGV localization and associated ultrastructural modifications are reported and discussed, in the perspective of assisting management and control of the disease.

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.

Age-related structural alterations in human skeletal muscle fibers and mitochondria are sex specific: relationship to single-fiber function.

PubMed

Callahan, Damien M; Bedrin, Nicholas G; Subramanian, Meenakumari; Berking, James; Ades, Philip A; Toth, Michael J; Miller, Mark S

2014-06-15

Age-related loss of skeletal muscle mass and function is implicated in the development of disease and physical disability. However, little is known about how age affects skeletal muscle structure at the cellular and ultrastructural levels or how such alterations impact function. Thus we examined skeletal muscle structure at the tissue, cellular, and myofibrillar levels in young (21-35 yr) and older (65-75 yr) male and female volunteers, matched for habitual physical activity level. Older adults had smaller whole muscle tissue cross-sectional areas (CSAs) and mass. At the cellular level, older adults had reduced CSAs in myosin heavy chain II (MHC II) fibers, with no differences in MHC I fibers. In MHC II fibers, older men tended to have fewer fibers with large CSAs, while older women showed reduced fiber size across the CSA range. Older adults showed a decrease in intermyofibrillar mitochondrial size; however, the age effect was driven primarily by women (i.e., age by sex interaction effect). Mitochondrial size was inversely and directly related to isometric tension and myosin-actin cross-bridge kinetics, respectively. Notably, there were no intermyofibrillar or subsarcolemmal mitochondrial fractional content or myofilament ultrastructural differences in the activity-matched young and older adults. Collectively, our results indicate age-related reductions in whole muscle size do not vary by sex. However, age-related structural alterations at the cellular and subcellular levels are different between the sexes and may contribute to different functional phenotypes in ways that modulate sex-specific reductions in physical capacity with age. Copyright © 2014 the American Physiological Society.

Side Effects of Neem Oil on the Midgut Endocrine Cells of the Green Lacewing Ceraeochrysa claveri (Navás) (Neuroptera: Chrysopidae).

PubMed

Scudeler, E L; Santos, D C

2014-04-01

We described the ultrastructure of Ceraeochrysa claveri (Navás) midgut endocrine cells in larva, pupa, and adult, and evaluated the side effects of ingested neem oil, a botanical insecticide obtained from the seeds of the neem tree (Azadirachta indica), on these cells. During the larval period, C. claveri were fed (ad libitum) Diatraea saccharalis (F.) eggs treated with neem oil at concentrations of 0.5%, 1%, or 2%. Transmission electron microscopy showed that two subtypes of endocrine cells, namely granular and vesicular, occurred in the midgut epithelium during the three stages of the life cycle. Both cell types did not reach the midgut lumen and were positioned basally in the epithelium. The endocrine cells did not show extensive infoldings of the basal plasma membrane, and there were numerous secretory granules in the basal region of the cytoplasm. In the granular endocrine cells, the granules were completely filled with a dense matrix. In the vesicular endocrine cells, the main secretory products consisted of haloed vesicles. Ultrastructural examination indicated that only the granular endocrine cells exhibited signs of morphologic changes of cell injury present in all life cycle stages after the larvae were chronically exposed to neem oil by ingestion. The major cellular damage consisted of dilatation and vesiculation of the rough endoplasmic reticulum and the development of smooth endoplasmic reticulum and mitochondrial swelling. Our data suggest that cytotoxic effects on midgut endocrine cells can contribute to a generalized disruption of the physiological processes in this organ due to a general alteration of endocrine function.

Oral mucosal lipids are antibacterial against Porphyromonas gingivalis, induce ultrastructural damage, and alter bacterial lipid and protein compositions.

PubMed

Fischer, Carol L; Walters, Katherine S; Drake, David R; Dawson, Deborah V; Blanchette, Derek R; Brogden, Kim A; Wertz, Philip W

2013-09-01

Oral mucosal and salivary lipids exhibit potent antimicrobial activity for a variety of Gram-positive and Gram-negative bacteria; however, little is known about their spectrum of antimicrobial activity or mechanisms of action against oral bacteria. In this study, we examine the activity of two fatty acids and three sphingoid bases against Porphyromonas gingivalis, an important colonizer of the oral cavity implicated in periodontitis. Minimal inhibitory concentrations, minimal bactericidal concentrations, and kill kinetics revealed variable, but potent, activity of oral mucosal and salivary lipids against P. gingivalis, indicating that lipid structure may be an important determinant in lipid mechanisms of activity against bacteria, although specific components of bacterial membranes are also likely important. Electron micrographs showed ultrastructural damage induced by sapienic acid and phytosphingosine and confirmed disruption of the bacterial plasma membrane. This information, coupled with the association of treatment lipids with P. gingivalis lipids revealed via thin layer chromatography, suggests that the plasma membrane is a likely target of lipid antibacterial activity. Utilizing a combination of two-dimensional in-gel electrophoresis and Western blot followed by mass spectroscopy and N-terminus degradation sequencing we also show that treatment with sapienic acid induces upregulation of a set of proteins comprising a unique P. gingivalis stress response, including proteins important in fatty acid biosynthesis, metabolism and energy production, protein processing, cell adhesion and virulence. Prophylactic or therapeutic lipid treatments may be beneficial for intervention of infection by supplementing the natural immune function of endogenous lipids on mucosal surfaces.

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

Ultrastructure of hybrid chitosan-glycerol phosphate blood clots by environmental scanning electron microscopy.

PubMed

Iliescu, M; Hoemann, C D; Shive, M S; Chenite, A; Buschmann, M D

2008-03-01

Chitosan-based polymers have been extensively studied for biomedical applications. Recently, liquid solutions of chitosan in a glycerol phosphate buffer (chitosan-GP) with physiological pH and osmolality were mixed with autologous blood to form hybrid chitosan-GP/blood implants that improved the repair of articular cartilage lesions in a large animal model. The mixture of chitosan-GP and blood forms a viscous liquid, which solidifies in minutes via normal blood coagulation as well as chitosan-mediated mechanisms. Here we have examined the ultrastructure of these chitosan-GP/blood clots as well as regular blood clots and chitosan-GP gels, the latter produced by heating. Both unfixed and fixed samples of chitosan-GP/blood clots, regular blood clots, and chitosan-GP gels were investigated by environmental scanning electron microscopy (ESEM) in conjunction with energy dispersive X-ray spectrometry (EDS), the former permitting direct observation of the ultrastructure in hydrated conditions simulating the natural state. By examination of unfixed specimens using ESEM we found that chitosan formed a network structure in both chitosan-GP gels and chitosan-GP/blood clots; however this structure was altered by aldehyde fixation to produce artifactual aggregates of chitosan microparticles. We were also able to identify chitosan in chitosan-GP/blood clots by washing samples in low concentration NaCl solutions followed by local EDS analyses to identify excess chloride versus sodium, and thus presence of cationic chitosan in analyzed features. Additional results indicated that the majority of glycerol phosphate diffuses freely from chitosan-GP gels (by EDS of phosphorus) and that hyperosmotic paraformaldehyde-based fixatives (i.e. 4% w/v) significantly disturb erythrocyte morphology in fixed whole blood clots. (c) 2007 Wiley-Liss, Inc.

Charting the Isophasic Endophyte of Dwarf Mistletoe Arceuthobium douglasii (Viscaceae) in Host Apical Buds

PubMed Central

LYE, DAVID

2006-01-01

• Background and Aims Dwarf mistletoes (Arceuthobium; Viscaceae) are highly specialized dioecious angiosperms parasitic on many gymnosperm hosts in the northern hemisphere. Several dwarf mistletoe species are capable of inducing an unusual form of isophasic infection in which the internal (endophytic) system proliferates even into the apical buds of its hosts. Studies of the internal endophytic system have, for the most part, focused on the parasite within secondary host tissues. The present anatomical and ultrastructural study characterizes the growth pattern of the isophasic endophytic system of Arceuthobium douglasii within the dormant apical buds of Pseudotsuga menziesii. • Methods Semi-thin serial sections from dwarf mistletoe-infected host apical buds were mounted, stained and micrographed. Graphic files were created from the serial micrographs and these files were stacked. These stacked files were utilized to describe the pattern of growth of the endophyte within the host tissue. The interface between cells of the mistletoe and host was also examined at the ultrastructural level by transmission electron microscopy. • Key Results By utilizing a novel technique of superimposed graphics, the current study reveals an organized pattern of mistletoe distribution that penetrates further into host tissues than previously known. A consistent pattern of growth occurring even into the preformed leaves of the host is documented. • Conclusions The apparently non-intrusive growth of the parasite appears to be developmentally synchronized with that of the host. No symplastic connections were observed in the ultrastructural examination of the parasite/host interface within the apical buds of Pseudotsuga menziesii parasitized by A. douglasii or of Pinus contorta parasitized by A. americanum. PMID:16613903

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 effect of vitamin C deficiency and chronic ultraviolet-B exposure on corneal ultrastructure: a preliminary investigation

PubMed Central

Hayes, Sally; Cafaro, Thamara A.; Boguslawska, Patrycja J.; Kamma-Lorger, Christina S.; Boote, Craig; Harris, Jonathan; Young, Robert; Hiller, Jennifer; Terrill, Nicholas; Meek, Keith M.

2011-01-01

Purpose In the visually debilitating condition of climatic droplet keratopathy, corneal transparency is progressively lost. Although the precise cause of the disease and the mechanism by which it progresses are not known, a lifetime exposure to high solar radiation and a vitamin C–deficient diet may be involved in its development. This study examines the effect of dietary ascorbate levels and ultraviolet (UV)-B exposure on corneal stromal structure. Methods Eight guinea pigs were divided into four treatment groups (A, B, C, and D). For 15 weeks, Groups A and C were fed an ascorbate-rich diet (2 mg/100 g bodyweight/day), while Groups B and D received an ascorbate-deficient diet (0.07 mg/100 g bodyweight/day). For the last 12 weeks of the study, Groups C and D also experienced chronic UVB exposure (0.12 J/cm2 for 40 min/day). Following euthanasia, the corneas were enucleated and their stromal ultrastructure examined using X-ray scattering and electron microscopy. Results UVB exposure resulted in an increased corneal thickness (p<0.001), but this was not accompanied by a widespread expansion of the collagen fibrillar array, and in the case of ascorbate-deficient animals, stromal thickening was associated with the compaction of collagen fibrils (p<0.01). Neither UVB exposure nor ascorbic acid deficiency caused any change in the average diameter or D-periodicity of the stromal collagen fibrils. Conclusions UVB-induced changes in the corneal ultrastructure were most pronounced in animals fed an ascorbic acid–deficient diet. This suggests that ascorbic acid may play a vital role in protecting the corneal stroma from the harmful effects of UVB. PMID:22171156

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

PubMed

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

2016-01-01

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

Structural and ultrastructural studies of the urinary tract of mice inoculated with Lactobacillus fermentum.

PubMed

Silva de Ruiz, C; del R Rey, M; Nader-Macías, M E

2003-06-01

To assess, using structural and ultrastructural studies of the urinary tract, the effects of the intraurethral inoculation of lactobacilli (probiotic treatment) as lactobacilli are the predominant micro-organisms of the urogenital tract of humans, monkeys and mice. Previous work showed the protective effect of Lactobacillus fermentum CRL 1058 intraurethrally inoculated against the challenge of uropathogenic Escherichia coli. There was also an effect of oestrogens and antibiotics in the kinetics of colonization of both micro-organisms in mice. In the present study L. fermentum was inoculated with agarose beads (107 colony-forming units) and the number of micro-organisms determined by plating in selective media, giving a high degree of colonization in all the organs studied. The urinary tract organs were processed by histological and electron microscopy techniques standardized in our laboratory. The intraurethral inoculation of lactobacilli produced no adverse effects or significant changes in any of the organs assessed (kidney, ureter, bladder or urethra), when evaluated by histological and ultrastructural techniques. The use of lactobacilli as a probiotic treatment is probably safe.

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

Histological, ultrastructural and heat shock protein 70 (HSP70) responses to heat stress in the sea cucumber Apostichopus japonicus.

PubMed

Xu, Dongxue; Sun, Lina; Liu, Shilin; Zhang, Libin; Yang, Hongsheng

2015-08-01

The aquaculture industry for Apostichopus japonicus has suffered severe economic and resource losses due to high temperature in recent summers. There is increasing concern about the effect of high temperature on this species. Histological, ultrastructural and HSP70 responses to heat stress were investigated in the intestine of A. japonicus. Tissue degradation was observed in muscular, submucosal and mucosal layers, with significant decrease in plicae circulares of the mucosal layer. Ultrastructural damage intensified with increasing stress time, and indicators of cell apoptosis were evident after 192 h heat stress. Immunostaining showed HSP70 mainly in mucosa and serosa, with faint staining in non-stressed individuals (the control group) and denser staining under stress (the 6, 48 and 192 h groups). Western blot detection confirmed ocurrence of HSP70 in all groups and significant up-regulation under stress. The rapid and persistent response of HSP70 implies its critical role in the heat shock response of A. japonicus. Copyright © 2015 Elsevier Ltd. All rights reserved.

Nucleolar evolution and coiled bodies during meiotic prophase in Olea europaea: differential localization of nucleic acids.

PubMed

Olmedilla, A; de Dios Alché, J; Rodríguez-García, M I

1997-10-01

We studied the ultrastructural evolution of the nucleolus during meiotic prophase in olive microsporocytes. During prophase, nuclear bodies morphologically similar to coiled bodies were observed. The nucleic acid composition of these bodies was examined in microsporocytes using electron microscopic techniques with EDTA preferential ribonucleoprotein staining, anti-DNA immunolabeling, the in situ terminal deoxynucleotidyl transferase-immunogold technique, and in situ hybridization with 18S rRNA and U3 snoRNA digoxigenin-labeled probes. The ultrastructural appearance of the meiocyte nucleolus indicated a low level of activity from the early prophase stage: the granular component was practically absent and nucleoli were constituted almost exclusively by dense fibrillar component containing large fibrillar centers that lacked chromatin inclusions. However, the appearance of reactivation vacuoles in the nucleolus during zygotene and high levels of rRNA in the nucleoplasm during pachytene support the presence of a peak in rRNA synthesis. Our results also show that the nuclear bodies that appear during prophase I are ribonucleoproteinaceous in nature; neither DNA nor ribosomal RNA were detected. The presence of U3 snoRNA, as shown by in situ hybridization in nuclear bodies from plant material, is also evidence that these structures are coiled bodies. We suggest that coiled bodies are involved not only in pre- and post-splicing events but also in the storage, transport or recycling of rRNA maturation elements.

Studies on proinsulin and proglucagon biosynthesis and conversion at the subcellular level: I. Fractionation procedure and characterization of the subcellular fractions

PubMed Central

Noe, BD; Baste, CA; Bauer, GE

1977-01-01

Anglerfish islets were homogenized in 0.25 M sucrose and separated into seven separate subcellular fractions by differential and discontinuous density gradient centrifugation. The objective was to isolate microsomes and secretory granules in a highly purified state. The fractions were characterized by electron microscopy and chemical analyses. Each fraction was assayed for its content of protein, RNA, DNA, immunoreactive insulin (IRI), and immunoreactive glucagon (IRG). Ultrastructural examination showed that two of the seven subcellular fractions contain primarily mitochondria, and that two others consist almost exclusively of secretory granules. A fifth fraction contains rough and smooth microsomal vesicles. The remaining two fractions are the cell supernate and the nuclei and cell debris. The content of DNA and RNA in all fractions is consistent with the observed ultrastructure. More than 82 percent of the total cellular IRI and 89(percent) of the total cellular IRG are found in the fractions of secretory granules. The combined fractions of secretory granules and microsomes consistently yield >93 percent of the total IRG. These results indicate that the fractionation procedure employed yields fractions of microsomes and secretory granules that contain nearly all the immunoassayable insulin and glucagons found in whole islet tissue. These fractions are thus considered suitable for study of proinsulin and proglucagon biosynthesis and their metabolic conversion at the subcellular level. PMID:328517

Therapeutic enhancement of newly derived bacteriocins against Giardia lamblia.

PubMed

Amer, Eglal I; Mossallam, Shereen F; Mahrous, Hoda

2014-11-01

Trials for identifying efficient anti-giardial agents are still ongoing. Nowadays, bacteriocins have attracted the attention as potential antimicrobial compounds. For the first time, the current study evaluated the therapeutic efficacy of bacteriocins derived from newly isolated Egyptian strains of probiotics Lactobacilli; L. acidophilus (P106) and L. plantarum (P164) against Giardia lamblia. Bacteriocins' efficacy was evaluated both in vitro; by growth inhibition and adherence assays, and in vivo; through estimation of parasite density, intestinal histopathological examination and ultrastructural analysis of Giardia trophozoites. In vivo bacteriocins' clinical safety was assessed. In vitro results proved that 50 µg of L. acidophilus bacteriocin induced reduction of the mean Giardia lamblia trophozoites by 58.3 ± 4.04%, while at lower concentrations of 10 and 20 µg of both L. acidophilus and L. plantarum, non significant reduction of the mean parasite density was achieved. In vitro trophozoites adherence was susceptible to the tested bacteriocins at all studied concentrations with variable degrees, while the highest adherence reduction was demonstrated using 50 µg of L acidophilus bacteriocin. In vivo, oral inoculation of 50 µg/mouse L. acidophilus bacteriocin for 5 successive days resulted in a noteworthy decline of the intestinal parasite density, along with amelioration of intestinal pathology of infected mice. Ultrastructural examination proved thatfive doses of L. acidophilus bacteriocin showed marked changes in cellular architecture of the trophozoites with evident disorganization of the cell membrane, adhesive disc and cytoplasmic components. This is the first reported study of the safe anti-giardial efficacy of L. acidophilus (P106) derived bacteriocin, hence highlighting its great promise as a potential therapeutic safe alternative to existing commercial drugs. Copyright © 2014 Elsevier Inc. All rights reserved.

Electron microscope study of Sarcocystis sp

USGS Publications Warehouse

Zeve, V.H.; Price, D.L.; Herman, C.M.

1966-01-01

Sarcocystis sp. obtained from wild populations of grackles, Quiscalus quiscula (Linn.), were examined to clarify the effect of the parasite on the host. Electron micrographs are presented to show areas of muscle destruction adjacent to the parasite which appear to be mechanically produced by the parasite. The microtubules within the villus-like projections of the cyst suggest that their possible function is absorptive and/or conductive with regard to the production of a toxin or the conveyance of nutritive material to the developing cells. The proposed function of submembranous filaments and their relation to the conoid is discussed. Similarities in the ultrastructure to Toxoplasma and other protozoa tend to negate the relegation of Sarcocystis to the fungi and further emphasize its protozoan nature.

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.

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.

Pancreatic endocrine tumour with cytoplasmic keratin whorls. Is the term "rhabdoid" appropriate?

PubMed

Chetty, R; Asa, S L

2004-10-01

A 50 year old woman presented with acute abdominal pain accompanied by nausea and vomiting and was found to have a mass in the head of the pancreas by imaging. The clinical impression was of a pancreatic carcinoma and a Whipple's procedure was performed. Microscopic examination of the tumour showed it to be a low grade neuroendocrine carcinoma arranged in a tubuloacinar or tubulopapillary pattern, and composed of cells harbouring very prominent intracytoplasmic inclusions. These inclusions varied in appearance from being pale pink and hyaline in quality to more eosinophilic and globular causing displacement of the nucleus. Ultrastructural examination showed typical paranuclear aggregates of intermediate filaments. Inclusions of this type have been described previously as "signet ring like" and "rhabdoid". It was felt that the inclusions more closely resemble the fibrous bodies that are seen in pituitary adenomas. In addition, it is suggested that both signet ring and rhabdoid are not appropriate because they do not reflect histogenesis and are not necessarily reflective of tumour biology. It is suggested that the term "cytokeratin aggresomes" should be used to describe this distinctive phenotype.

Ultrastructural aspects of mouse nerve-muscle preparation exposed to Bothrops jararacussu and Bothrops bilineatus venoms and their toxins BthTX-I and Bbil-TX: Unknown myotoxic effects.

PubMed

Melaré, Rodolfo; Floriano, Rafael Stuani; Gracia, Marta; Rodrigues-Simioni, Léa; Cruz-Höfling, Maria Alice da; Rocha, Thalita

2016-11-01

Bites by Bothrops snakes normally induce local pain, haemorrhage, oedema and myonecrosis. Mammalian isolated nerve-muscle preparations exposed to Bothrops venoms and their phospholipase A 2 toxins (PLA 2 ) can exhibit a neurotoxic pattern as increase in frequency of miniature end-plate potentials (MEPPs) as well as in amplitude of end-plate potentials (EPPs); neuromuscular facilitation followed by complete and irreversible blockade without morphological evidence for muscle damage. In this work, we analysed the ultrastructural damage induced by Bothrops jararacussu and Bothrops bilineatus venoms and their PLA 2 toxins (BthTX-I and Bbil-TX) in mouse isolated nerve-phrenic diaphragm preparations (PND). Under transmission electron microscopy (TEM), PND preparations previously exposed to B. jararacussu and B. bilineatus venoms and BthTX-I and Bbil-TX toxins showed hypercontracted and loosed myofilaments; unorganized sarcomeres; clusters of edematous sarcoplasmic reticulum and mitochondria; abnormal chromatin distribution or apoptotic-like nuclei. The principal affected organelles, mitochondria and sarcoplasmic reticulum, were those related to calcium buffering and, resulting in sarcomeres and myofilaments hypercontraction. Schwann cells were also damaged showing edematous axons and mitochondria as well as myelin sheath alteration. These ultrastructural changes caused by both of Bothrops venoms and toxins indicate that the neuromuscular blockade induced by them in vitro can also be associated with nerve and muscle degeneration. © 2016 Wiley Periodicals, Inc.

Muscle morphology and mitochondrial investigations of a family with autosomal dominant cerebellar ataxia and retinal degeneration mapped to chromosome 3p12-p21.1.

PubMed

Forsgren, L; Libelius, R; Holmberg, M; von Döbeln, U; Wibom, R; Heijbel, J; Sandgren, O; Holmgren, G

1996-12-01

The autosomal dominant cerebellar ataxias (ADCA) are a group of neurodegenerative disorders with ataxia and dysarthria as early and dominant signs. In ADCA type II, retinal degeneration causes severe visual impairment. ADCA type II has recently been mapped to chromosome 3p by three independent groups. In the family with ADCA type II studied here, the disease has been mapped to chromosome 3p12-p21.1. Histochemical examination of muscle biopsies in 5 cases showed slight neurogenic atrophy and irregular lobulated appearance or focal decreases of enzyme activity when staining for NADH dehydrogenase, succinic dehydrogenase and cytochrome oxidase. Ragged-red fibres were scarce. Electron microscopic examination showed uneven distribution of mitochondria with large fibre areas devoid of mitochondria and/or large subsarcolemmal accumulations of small rounded mitochondria, and frequent autophagic vacuoles. These vacuoles contained remnants of multiple small rounded organelles, possibly mitochondria, and had a remarkably consistent ultrastructural appearance. Biochemical investigation of mitochondrial function showed reduced activity of complex IV and slightly reduced activity of complex I in the respiratory chain in a severely affected child while no abnormalities were found in his affected uncle.

Clinical, cellular, microscopic, and ultrastructural studies of a case of fibrogenesis imperfecta ossium

PubMed Central

Barron, Melissa L; Rybchyn, Mark S; Ramesh, Sutharshani; Mason, Rebecca S; Fiona Bonar, S; Stalley, Paul; Khosla, Sundeep; Hudson, Bernie; Arthur, Christopher; Kim, Edward; Clifton-Bligh, Roderick J; Clifton-Bligh, Phillip B

2017-01-01

Fibrogenesis imperfecta ossium is a rare disorder of bone usually characterized by marked osteopenia and associated with variable osteoporosis and osteosclerosis, changing over time. Histological examination shows that newly formed collagen is abnormal, lacking birefringence when examined by polarized light. The case presented demonstrates these features and, in addition, a previously undocumented finding of a persistent marked reduction of the serum C3 and C4. Osteoblasts established in culture from a bone biopsy showed abnormal morphology on electron microscopy and increased proliferation when cultured with benzoylbenzoyl-ATP and 1,25-dihydroxyvitamin D, contrasting with findings in normal osteoblasts in culture. A gene microarray study showed marked upregulation of the messenger RNA (mRNA) for G-protein-coupled receptor 128 (GPR 128), an orphan receptor of unknown function and also of osteoprotegerin in the patient’s osteoblasts in culture. When normal osteoblasts were cultured with the patient’s serum, there was marked upregulation of the mRNA for aquaporin 1. A single pathogenetic factor to account for the features of this disorder has not been defined, but the unique findings described here may facilitate more definitive investigation of the abnormal bone cell function. PMID:28326223

Ultrastructural diversity between centrioles of eukaryotes.

PubMed

Gupta, Akshari; Kitagawa, Daiju

2018-02-16

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

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.

The ultrastructure of imaginal disc cells in primary cultures and during cell aggregation in continuous cell lines.

PubMed

Peel, D J; Johnson, S A; Milner, M J

1990-01-01

We have examined the ultrastructure of cellular vesicles in primary cultures of wing imaginal disc cells of Drosophila melanogaster. These cells maintain the apico-basal polarity characteristic of epithelial cells. The apical surfaces secrete extracellular material into the lumen of the vesicle from plasma membrane plaques at the tip of microvilli. During the course of one passage, cells from the established cell lines grow to confluence and then aggregate into discrete condensations joined by aligned bridges of cells. Cells in these aggregates are tightly packed, and there appears to be a loss of the epithelial polarity characteristic of the vesicle cells. Elongated cell extensions containing numerous microtubules are found in aggregates, and we suggest that these may be epithelial feet involved in the aggregation process. Virus particles are commonly found both within the nucleus and the cytoplasm of cells in the aggregates.

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.

Ultrastructural observations on giardiasis in a mouse model. II. Endosymbiosis and organelle distribution in Giardia muris and Giardia lamblia.

PubMed

Nemanic, P C; Owen, R L; Stevens, D P; Mueller, J C

1979-08-01

Ultrastructural observations of Giardia muris in a mouse model revealed endosymbiotic microbes not previously reported in Giardia. Endosymbionts 240--360 nm wide, 600--1,400 nm long, and with an internal structure similar to that of bacilli were not seen entering Giardia but were found and appeared to divide within Giardia. No evidence was found of digestion of the endosymbionts by the giardia host in either the trophozoite or the cyst form. Endosymbionts were concentrated centrally around the nuclear area and were uncommon in peripheral feeding regions. The same cellular organelles seen in G. muris were found in Giardia lamblia from human jejunal biopsy material, but no endosymbionts were identified in G. lamblia trophozoites from the seven patients examined. Endosymbionts within Giardia may be found to alter trophozoite pathogenicity, metabolism, range of infectivity, antigenic surface characteristics, and host specificity, as they do in other protozoa.

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

PubMed

Sogayar, M I; Gregório, E A

1989-01-01

Trophozoites of the Giardia muris group from hamsters, domestic rats and mice and of the Giardia duodenalis group from hamsters and domestic rats were examined by transmission electron microscopy. The basic ultrastructure of the trophozoites was similar. Differences were shown in the morphology of the ventrolateral flange of the trophozoites of Giardia muris and Giardia duodenalis groups. Marginal plates are less developed in the species of the Giardia duodenalis group. In this group, the distal extremity of the lateral flange is short and thick and the marginal plate does not penetrate into the distal extremity of the flange. In the Giardia muris group, the ventro-lateral flange is well developed and narrow and the marginal plate penetrates the distal extremity of the flange. The osmiophilic lamella, which accompanies the dorsal surface of the marginal plate is seen only in the Giardia muris group.

Echinobothrium chisholmae n. sp. (Cestoda, Diphyllidea) from the giant shovel-nose ray Rhinobatos typus from Australia, with observations on the ultrastructure of its scolex musculature and peduncular spines.

PubMed

Jones, M K; Beveridge, I

2001-09-01

Echinobothrium chisholmae n. sp. is described from Rhinobatos typus Bennett (Rhinobatidae), collected from Heron Island, Great Barrier Reef, Australia. E. chisholmae differs from all congeners in possessing 11 hooks in each dorsal and ventral group on the rostellum and groups of 3-6 hooklets on either side of the hooks. A single metacestode of E. chisholmae was collected from the decapod crustacean Penaeus longistylus Kubo. Yellow pigmentation of the cephalic peduncle in immature adults is caused by the accumulation of large vesicles in the distal cytoplasm of the tegument. The vesicles probably provide materials for spine formation. Ultrastructural examination of the rostellar musculature revealed that the muscles are stratified (striated-like), consisting of a periodic repetition of sarcomeres separated by perforated Z-like lines that are oblique to the long axes of the myofilaments.

Pathogenicity and ultrastructural studies of the mode of penetration by Phoma strasseri in peppermint stems and rhizomes.

PubMed

Zimowska, Beata

2012-01-01

Pathogenicity and ultrastructural investigation of the inoculation of peppermint stems and rhizomes with Phoma strasseri conidia was undertaken using scanning and transmission electron microscopy to examine the host-parasite relationship. Pathogenicity experiments demonstrated that all tested P. strasseri isolates had infected the stems and rhizomes of peppermint. Of all inoculation methods, direct placement of colonized agar plugs on damaged epidermis and soaking stems and rhizomes in conidial suspension were the most effective. The behavior of the conidia deposited on the stems and rhizomes was investigated at different time intervals after inoculation: 6, 16, 24, 36 and 48 h. Conidia produced an appressorium directly at the end of a short germ tube. Appressoria were formed over the cuticle, but never over stomata. Direct penetration to host tissue through the cuticle was observed. The spore and hyphae were covered with a mucilaginous sheath.

Light Affects the Chloroplast Ultrastructure and Post-Storage Photosynthetic Performance of Watermelon (Citrullus lanatus) Plug Seedlings

PubMed Central

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

2014-01-01

Watermelon [Citrullus lanatus (Thunb.) Matsum. and Nakai] plug seedlings were stored at 15°C in the light at a photosynthetic photon flux density of 15 µmol·m−2·s−1 or in darkness for 6 days, to evaluate their chloroplast ultrastructure, and associated photosynthetic characteristics. Storage in the dark caused swelling, disordered granal arrangement, and starch grain disappearance in the chloroplasts. In contrast, the chloroplasts stored in the light were relatively normal. As a result, the light-stored seedlings had a significantly higher chlorophyll content, Fv/Fm, and Pn than did dark-stored seedlings. Regardless of whether the seedlings were stored in light or darkness, the Gs and Ls of the seedlings significantly decreased, while the Ci obviously increased when the Pn decreased after 6 days of storage. This result suggests that the decreased Pn is not solely a stomatal effect, as the effects on the chloroplasts contributed to this photosynthetic inhibition. Six days after transplanting, seedlings that were stored in the light or darkness for 2 or 4 days showed complete recovery of chloroplast ultrastructure, chlorophyll content, Fv/Fm, Gs and Pn. When the storage period increased to 6 days, the dark-stored seedlings had a significantly lower Fv/Fm and Pn than the light-stored and control seedlings 6 days after transplanting, which was mainly ascribed to incomplete recovery of chloroplast ultrastructure. Furthermore, the light-stored seedlings exhibited a significantly higher shoot dry weight during storage and a higher percentage dry weight increase after transplanting than the dark-stored seedlings. These effects were enhanced by prolonged storage (4 to 6 days). This study demonstrated that dim light during storage is beneficial for maintaining chloroplast ultrastructure as well as photosynthetic efficiency in watermelon seedlings, thus contributing to the rapid recovery of post-storage photosynthetic performance, which ensures the transplant quality of the seedlings after removal from storage. PMID:25340859

Responses of photosynthetic properties and chloroplast ultrastructure of two moss crusts from a desert biological soil crust to supplementary UV-B radiation

NASA Astrophysics Data System (ADS)

Hui, Rong; Li, Xinrong; Zhao, Yang; Pan, Yanxia

2016-04-01

Our understanding of plant responses to supplementary ultraviolet-B (UV-B) radiation due to stratospheric ozone depletion has improved over recent decades. However, research on biological soil crusts (BSCs) is scarce and it remains controversial. Laboratory studies were conducted to investigate the influence of UV-B radiation on the Bryum argenteum and Didymodon vinealis isolated from BSCs, which are both dominant species in moss crusts found within patches of shrubs and herbs in the Tengger Desert of northern China. The aim of the current work was to evaluate whether supplementary UV-B radiation affected photosynthetic properties and chloroplast ultrastructure of two moss crusts and whether response differences were observed between the crusts. Four levels of UV-B radiation of 2.75 (control), 3.08, 3.25, and 3.41 W m-2 was achieved using fluorescence tube systems for 10 days, simulating 0, 6, 9, and 12% of stratospheric ozone at the latitude of Shapotou, respectively. We measured photosynthetic apparatus as assessed by chlorophyll a fluorescence parameters, photosynthetic pigment contents, and observations of chloroplast ultrastructure. Additionally, soluble proteins and UV-B absorbing compounds were simultaneously investigated. The results of this study showed that chlorophyll a fluorescence parameters (i.e., the maximal quantum yield of PSII photochemistry, the effective quantum yield of PSII photochemistry, and photochemical quenching coefficient), photosynthetic pigment contents, soluble protein contents, total flavonoid contents and the ultrastructure were negatively influenced by elevated UV-B radiation and the degree of detrimental effects significantly increased with the intensity of UV-B radiation. Moreover, results demonstrated that the negative effects on photosynthesis and chloroplast ultrastructure were more serious in B. argenteum than that in D. vinealis. These results may not only provide a potential mechanism for supplemental UV-B effects on photosynthesis of moss crusts, but also establish a theoretical basis for further studies of adaptation and response mechanisms of desert ecosystems under further ozone depletion.

Ultrastructural studies of synthetic apatite crystals.

PubMed

Arends, J; Jongebloed, W L

1979-03-01

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

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.

Mixed pituitary adenoma/craniopharyngioma: clinical, morphological, immunohistochemical and ultrastructural study of a case, review of the literature, and pathogenetic and nosological considerations.

PubMed

Finzi, Giovanna; Cerati, Michele; Marando, Alessandro; Zoia, Cesare; Ferreli, Fabio; Tomei, Giustino; Castelnuovo, Paolo; La Rosa, Stefano; Capella, Carlo

2014-02-01

Mixed pituitary adenoma/craniopharyngiomas are very rare tumors. Their pathogenesis is still unclear and it is not known whether they are collision tumors derived from independent stem cells or whether they originate from a single stem cell undergoing divergent differentiation. The latter hypothesis is supported by the close commixture between the two tumor components with transition areas that has been previously described. However, "hybrid" cells with both pituitary adenoma and craniopharyngioma features have never been described. In this paper we report a case of mixed pituitary adenoma/craniopharyngioma observed in a 75-year-old woman presenting with diplopia and slight increase of serum prolactin, who underwent endoscopic endonasal trans-sphenoidal tumor resection. Histologically, the tumor was composed of a typical pituitary silent subtype 2 ACTH cell adenoma admixed with islands of adamantinomatous craniopharyngioma. Electron microscopy showed that, in addition to distinct silent subtype 2 ACTH and craniopharyngioma cells, there were "hybrid" cells, showing characteristics of both pituitary adenoma and craniopharyngioma, consisting of small dense secretory granules, bundles of cytoplasmic filaments, and desmosomes. This ultrastructural finding was also confirmed by the presence of cells showing nuclear p40 expression and chromogranin A immunoreactivity. The close commixture between the two components and the ultrastructural and immunohistochemical findings demonstrate a common histogenesis of the two components and support the classification of the neoplasm as a mixed tumor. The patient completely recovered and, 10 months after surgery, head MR confirmed the complete resection of the lesion.

Behavior of sea urchin primary mesenchyme cells in artificial extracellular matrices.

PubMed

Katow, H

1986-02-01

The primary mesenchyme cells (PMCs) were separated from the mesenchyme blastulae of Pseudocentrotus depressus using differential adhesiveness of these cells to plastic Petri dishes. These cells were incubated in various artificial extracellular matrices (ECMs) including horse serum plasma fibronectin, mouse EHS sarcoma laminin, mouse EHS sarcoma type IV collagen, and porcine skin dermatan sulfate. The cell behavior was monitored by a time-lapse videomicrograph and analysed with a microcomputer. The ultrastructure of the artificial ECM was examined by transmission electron microscopy (TEM), while the ultrastructure of the PMCs was examined by scanning electron microscopy (SEM). The PMCs did not migrate in type IV collagen gel, laminin or dermatan sulfate matrix either with or without collagen gel, whereas PMCs in the matrix which was composed of fibronectin and collagen gel migrated considerably. However, the most active and extensive PMC migration was seen in the matrix which contained dermatan sulfate in addition to fibronectin and collagen gel. This PMC migration involved an increase not only of migration speed but also of proportion of migration-promoted cells. These results support the hypothesis that the mechanism of PMC migration involves fibronectin, collagen and sulfated proteoglycans which contain dermatan sulfate.

Synaptology of luteinizing hormone-releasing hormone (LHRH)-immunoreactive cells in the nervus terminalis of the gray short-tailed opossum (Monodelphis domestica).

PubMed

Zheng, L M; Pfaff, D W; Schwanzel-Fukuda, M

1990-05-08

Light and electron microscopic immunocytochemistry were used to examine the structure of LHRH neurons and fibers in the nervus terminalis of the gray short-tailed opossum (Monodelphis domestica). LHRH-immunoreactive neurons and fibers form a loose plexus within the fascicular network of the ganglion terminale on the median surface of the olfactory bulb. There are at least two populations of LHRH-immunoreactive neurons within the network of the ganglion terminale: fusiform and round neurons similar to those described in the forebrain. At the ultrastructural level, axosomatic and axodendritic contacts were seen between LHRH-immunoreactive and nonimmunoreactive elements in the ganglion terminale. These contacts were classified as 1) synaptic input, with asymmetric synapses seen between a nonimmunoreactive axon terminal and a LHRH-immunoreactive cell body or a nonimmunoreactive axon terminal and a LHRH-immunoreactive dendritic process. 2) synaptic output, with symmetric synapses seen between LHRH-immunoreactive and nonimmunoreactive processes. This study is the first systematic examination of the ultrastructure of the LHRH-immunoreactive neurons and their synaptic contacts in the nervus terminalis. The possible integrative roles for this LHRH-immunoreactive system are discussed.

Spermatozoan ultrastructure of scleractinian corals from the eastern Pacific: Pocilloporidae and Agariciidae

NASA Astrophysics Data System (ADS)

Steiner, S. C. C.; Cortés, J.

1996-06-01

Spermatozoa of Pocillopora damicornis, Pocillopora elegans (Astrocoeniina, Pocilloporidae) and Pavona gigantea (Fungiina, Agariciidae) from the eastern Pacific (Isla del Caño, Costa Rica) were examined using transmission electron microscopy. The hermaphroditic pocilloporids P. damicornis and P. elegans are spermiomorphologically very similar to hermaphroditic acroporids, being characterized by bullet-shaped nuclei and elongated mitochondria. Such traits have not been found in other families. Thus, the suborder Astrocoeniina, including pocilloporids and acroporids, can clearly be distinguished from other scleractinian suborders. This separation underlines the isolated position of the Astrocoeniina within the order Scleractinia following the evolutionary scheme of Wells. A conical sperm type, known from gonochoric species (sexes separate) from all families except Acroporidae and Pocilloporidae, was found in the gonochoric agariciid Pavona gigantea. This supports previous findings that gonochoric corals share a unique and common sperm structure regardless of which family they belong to. However, no gonochoric Astrocoeniina have ever been examined. Hence, the question whether the sperm type common to gonochorists is also represented in Astrocoeniina, which would undermine the ultrastructural distinction of Astrocoeniina and other suborders seen among hermaphrodites, as well as the systematic value of sperm structure within scleractinian corals, remains open.

Pathogenesis of Acute and Delayed Corneal Lesions After Ocular Exposure to Sulfur Mustard Vapor

DTIC Science & Technology

2012-03-01

using a vapor cup delivery system. The transition from acute to delayed injury was characterized by clinical, histological, and ultrastructural metrics...These data demonstrate a system-based approach combining ultrastructural analysis , histochemistry, and molecular evaluation that links architectural...predictive of the 11% of corneas that underwent asymptomatic recovery. Ultrastructural comparison of asymptomatic and MGK corneas at 8 weeks indicates that MGK

The effect of cryoprotectant on kangaroo sperm ultrastructure and mitochondrial function.

PubMed

McClean, Rhett; Holt, William V; Zee, Yeng Peng; Lisle, Allan; Johnston, Stephen D

2008-12-01

This study examined the effect of cryoprotectants (20% DMSO, a 10% DMSO/10% glycerol mixture, 20% glycerol and 1M sucrose solution) on kangaroo sperm structure and function, along with the effect of varying concentrations of glycerol on sperm mitochondrial function. Eastern grey kangaroo cauda epididymidal spermatozoa were incubated for 10 min at 35 degrees C in each cryoprotectant and the plasma membrane integrity (PMI) and motility assessed using light microscopy. The same samples were fixed for TEM and the ultrastructural integrity of the spermatozoa examined. To investigate the effect of glycerol on the kangaroo sperm mitochondrial function, epididymidal spermatozoa were incubated with JC-1 in Tris-citrate media at 35 degrees C for 20 min in a range of glycerol concentrations (0%, 5%, 10%, 15% and 20%) and the mitochondrial membrane potential (MMP) and plasma membrane integrity determined. As expected, incubation of spermatozoa in 20% glycerol for 10 min resulted in a significant reduction in motility, PMI and ultrastructural integrity. Interestingly, incubation in 20% DMSO resulted in no significant reduction in motility or PMI but a significant loss of structural integrity when compared to the control spermatozoa (0% cryoprotectant). However, 20% DMSO was overall less damaging to sperm ultrastructure than glycerol, a combination of 10% glycerol and 10% DMSO, and sucrose. While all glycerol concentrations had an adverse effect on mitochondrial function, the statistical models presented for the relationship between MMP and glycerol predicted that spermatozoa, when added to 20% glycerol, would lose half of their initial MMP immediately at 35 degrees C and MMP would halve after 19.4 min at 4 degrees C. Models for the relationship between PMI and glycerol predicted that spermatozoa would lose half of their initial PMI after 1.8 min at 35 degrees C and PMI would halve after 21.1 min at 4 degrees C. These results suggest that if glycerol is to be used as a cryoprotectant for kangaroo spermatozoa then it is best administered at 4 degrees C and that mitochondrial function is more sensitive to glycerol than PMI. Future research should be directed at investigating strategies that reduce exposure of spermatozoa to glycerol during processing and that test the cryoprotective properties of 20% DMSO for kangaroo spermatozoa.

[Effects of light intensities after anthesis on the photosynthetic characteristics and chloroplast ultrastructure in mesophyll cell of summer maize (Zea mays L. )].

PubMed

Gao, Jia; Cui, Hai Yan; Shi, Jian Guo; Dong, Shu Ting; Liu, Peng; Zhao, Bin; Zhang, Ji Wang

2018-03-01

We examined the changes of photosynthetic characteristics and chloroplast ultrastructure in mesophyll cell of summer maize in response to different light intensities in the field, with the summer maize hybrid Denghai 605 as experimental material. Two treatments of both shading (S) and increasing light (L) from flowering to physiological maturity stage were designed, with the ambient sunlight treatment as control (CK). Under shading treatment, poorly developed thylakoid structure, blurry lamellar structure, loose granum, large gap between slices and warping granum were the major characteristics in chloroplast. Meanwhile, photosynthetic rate (P n ), transpiration rate, stomatal conductance, chlorophyll content, and actual photo-chemical efficiency (Φ PSII ) decreased, whereas the maximal photochemical efficiency and non-photochemical quenching increased, which resulted in decreases in grain yield under shading treatment. However, a better development was observed in chloroplasts for L treatment, with the number of grana and lamellae increased and lamellae arranged compactly. In addition, P n and Φ PSII increased under L treatment, which increased grain yield. The chloroplast arrangement dispersed in mesophyll cells and chloroplast ultrastructure was destroyed after shading, and then chlorophyll synthesis per unit leaf area and photosynthetic capacity decreased. In contrast, the number of grana and lamellae increased and lamellae arranged compactly after increasing light, which are beneficial for corn yield.

High-pressure freezing and freeze substitution of Arabidopsis for electron microscopy.

PubMed

Austin, Jotham R

2014-01-01

The objectives of electron microscopy ultrastructural studies are to examine cellular architecture and relate the cell's structural machinery to dynamic functional roles. This aspiration is difficult to achieve if specimens have not been adequately preserved in a "living state"; hence specimen preparation is of the utmost importance for the success of any electron micrographic study. High-pressure freezing (HPF)/freeze substitution (FS) has long been recognized as the primer technique for the preservation of ultrastructure in biological samples. In most cases a basic HPF/freeze substitution protocol is sufficient to obtain superior ultrastructural preservation and structural contrast, which allows one to use more advanced microscopy techniques such as 3D electron tomography. However, for plant tissues, which have a thick cell wall, large water-filled vacuoles, and air spaces (all of which are detrimental to cryopreservation), these basic HPF/FS protocols often yield undesirable results. In particular, ice crystal artifacts and the staining of membrane systems are often poorly or negatively stained, which make 3D segmentation of a tomogram difficult. To overcome these problems, various aspects of the HPF/FS protocol can be altered, including the cryo-filler(s) used, freeze substitution cocktail, and the resin infiltration process. This chapter will describe these modifications for the preparation of plant tissues for routine electron microscopic studies, immunocytochemistry, and 3D tomographic electron imaging.

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.

[The ultrastructure and activities of free radical scavenger in discolored gingiva adjacent to porcelain fused to metal crowns].

PubMed

Zhang, Zhong-ti; Yan, Lu; Zhong, Ming; Yang, Xiao-dong; Ai, Hong-jun

2007-04-01

This study was designed to study the discolored gingiva adjacent to porcelain fused to metal (PFM) crowns in terms of ultrastructure , SOD and GSH activities in 40 cases. The discolored gingival ultrastructures were observed and metal X-ray energy level was analyzed;The activities of SOD and GSH were measured and compared with normal control by student's t test and one-way ANOVA with SPSS10.0 software package. The discolored gingival ultrastructure had changes compared with the normal gingiva. Nickel and chromium were not found in the particles through X-ray energy machine within the discolored gingiva adjacent to PFM crown. The activities of SOD and GSH in discolored gingiva were significantly different from control(P<0.05) and the values at 6 to 18 months were significantly different from those at other times. The ultrastructure underwent changes in discolored gingiva after PFM restoration; the activity of SOD and GSH in discolored gingiva changed to result in apoptosis, and discoloration.

Ultrastructure of extrusomes in hypotrichous ciliate Pseudourostyla nova

NASA Astrophysics Data System (ADS)

Zhou, Yao; Wang, Zhengjun; Zhang, Jun; Gu, Fukang

2011-01-01

The ultrastructure of extrusomes of the hypotrichous ciliate Pseudourostyla nova was observed in scanning and transmission electron microscopy and enzyme-cytochemistry. The results show that the distribution, morphological characteristics, morphogenesis process, and extrusive process of the extrusomes in P. nova are different from the trichocysts in Paramecium, suggesting that the extrusomes of P. nova can respond to environmental stimuli, play an important role in the defense of this species, and cannot be regarded as "trichocysts". The results also suggest that the extrusomes might be originated from the Golgi apparatus and mature in the cytoplasm; after the extrusion of mature extrusomes, the residual substance might be reabsorbed and reused by the ciliate cell via food vacuoles, and take part in material recycling of the cell.

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.

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.

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.

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

PubMed

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

2006-01-01

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

[Fabry nephropathy in a female with superposed IgA glomerulonephritis].

PubMed

Pisani, A; Sessa, A; Sabbatini, M; Andreucci, M V; Fusco, C; Balletta, M; Cianciaruso, B

2005-01-01

In Anderson-Fabry disease (AFd), the kidney is affected in all hemizygous males and in some heterozygous females. Female carriers can present subtle renal abnormalities due to glycosphingolipid (GSL) accumulation within renal cells. Renal biopsy is rarely performed in female Fabry patients because clinical renal manifestations are usually lacking. However, female carriers can accumulate GSL in their renal cells despite the absence of clinically evident kidney disease. We performed a kidney biopsy in a 52-year-old female patient, a Fabry disease carrier. The patient showed normal glomerular filtration rate, persistent microhematuria and proteinuria (about 1.7 g/24 hr), cornea "verticillata", and evident left ventricular hypertrophy. The molecular study documented a missense mutation R227Q in exon 5 of the alpha-galactosidase A gene. Optical microscopy showed electron-dense mesangial deposits due IgA glomerulonephritis, as confirmed by immunofluorescence. We decided to start therapy with angiotensin-converting enzyme inhibitors (ACE-I). After 8 months of treatment, the patient demonstrated proteinuria of 0.9 g/24 hr. To decide when to start treatment using enzyme replacement therapy (ERT) with human recombinant GAL A (Fabrazyme), we decided to perform an electron microscopy study of the renal biopsy. The renal ultrastructural findings were typical GSL inclusions in all kinds of glomerular cells, in tubular epithelial cells and in endothelial cells of interstitial capillaries, confirming the hypothesis of Fabry nephropathy. Consequently, Fabrazyme was given at a standard dose of 1 mg/kg every 2 weeks. After 24 months of combined treatment (ACE-I-Fabrazyme), proteinuria decreased to 0.2 g/24 hr. The importance of performing the ultrastructural examination of the kidney biopsy is stressed, especially in heterozygous Fabry patients to evaluate the need to treat them with ERT and to evaluate the degree of renal involvement.

A fish model for the study of the relationship between neuroendocrine and immune cells in the intestinal epithelium: Silurus glanis infected with a tapeworm.

PubMed

Dezfuli, B Sayyaf; DePasquale, J A; Castaldelli, G; Giari, L; Bosi, G

2017-05-01

Immunohistochemical, immunofluorescence and ultrastructural studies were conducted on a sub-population of 20 wels catfish Silurus glanis from a tributary of the River Po (Northern Italy). Fish were examined for the presence of ecto- and endo-parasites; in the intestine of 5 fish, 11 specimens of cestode Glanitaenia osculata were noted and was the only helminth species encountered. The architecture of intestine and its cellular features were nearly identical in either the uninfected S. glanis or in those harboring G. osculata. Near the site of worm's attachment, mucous cells, several mast cells (MCs), few neutrophils and some endocrine cells (ECs) were found to co-occur within the intestinal epithelium. MCs and neutrophils were abundant also in the submucosa. Immunohistochemical staining revealed that enteric ECs were immunoreactive to met-enkephalin, galanin and serotonin anti-bodies. The numbers of ECs, mucous cells and MCs were significantly higher in infected wels catfish (Mann-Whitney U test, p < 0.05). Dual immunofluorescence staining with the biotinylated lectin Sambucus nigra Agglutinin and the rabbit polyclonal anti-met-enkephalin or anti-serotonin, with parallel transmission electron microscopy, showed that ECs often made intimate contact with the mucous cells and epithelial MCs. The presence of numerous MCs in intestinal epithelium shows S. glanis to be an interesting model fish to study processes underlying intestinal inflammation elicited by an enteric worm. Immune cells, ECs and mucous cells of the intestinal epithelium have been described at the ultrastructural level and their possible functions and interactions together will be discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ultrastructural characterization of the tau-immunoreactive tubules in the oligodendroglial perikarya and their inner loop processes in progressive supranuclear palsy.

PubMed

Arima, K; Nakamura, M; Sunohara, N; Ogawa, M; Anno, M; Izumiyama, Y; Hirai, S; Ikeda, K

1997-06-01

Coiled bodies and interfascicular threads are conspicuous white matter abnormalities of brains of patients with progressive supranuclear palsy (PSP). Both structures are argyrophilic and immunoreactive for the microtubule-binding protein tau. This report concerns the ultrastructural localization of interfascicular threads and their relationship to coiled bodies in five PSP patients. We showed for the first time that abnormal tubules with a 13- to 15-nm diameter and fuzzy outer contours were the common structures of coiled bodies in the oligodendroglial perikarya and of interfascicular threads. Moreover, the tubules were immunolabeled by anti-tau antibodies. The abnormal tau-positive tubules of interfascicular threads were located in the inner loop of the myelin sheath. Our study further indicated that the thread-like structures in the white matter comprised, at least in part, oligodendroglial processes, and that they were also present in gray matter. We consider that the formation of coiled bodies in the perikarya and of interfascicular threads represents a common cytoskeletal abnormality of the oligodendroglia of PSP patients. Moreover, even though the white matter alterations of PSP resemble those of corticobasal degeneration, there are certain ultrastructural differences in the abnormal oligodendroglial tubules of the two diseases.

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

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.

[Effects of infrasound on ultrastructure of testis cell in mice].

PubMed

Wei, Ya-Ning; Liu, Jing; Shu, Qing; Huang, Xiao-Feng; Chen, Jing-Zao

2002-01-01

To investigate the effects of infrasound on ultrastructure of testis in mouse. Twelve male BALB/C mice were randomly divided into three groups according to exposed duration on 1, 7 and 14 day. The mice were separately exposed to infrasound environment under 8 Hz/90 dB, 8 Hz/130 dB, 16 Hz/90 dB, 16 Hz/130 dB 2 hours per day. There was another control group which had three mice were separated into module with no infrasound. All the mice were killed on schedule. Then all the sections of testis were observed under electronic microscope. The alterations of structure and the chromatin were observed. Some acute alteration in one day group was found in testis cell, such as cellular denaturation and necrosis, intercellular edema, mitochondria swelling, liposome hyperplasia. When the infrasound was up to 8 Hz/130 dB, the damage showed seriously. In 7 and 14 day group, the acute alteration was gradually decreased. A plenty of abnormal sperm were found. And other alteration was chromatin condense. The effect of variational frequency was important in ultrastructure. The infrasound markedly effected to testicular cell morphology and secreting function. Infrasound will lead to the alteration of procreation in mouse.

Antileishmanial activity and ultrastructural alterations of Leishmania (L.) chagasi treated with the calcium channel blocker nimodipine.

PubMed

Tempone, André Gustavo; Taniwaki, Noemi Nosomi; Reimão, Juliana Quero

2009-08-01

In a search for novel antileishmanial drugs, we investigated the activity of the calcium channel blocker nimodipine against Leishmania spp. and explored the ultrastructural damages of parasites induced by nimodipine after a short period of incubation. Nimodipine was highly effective against promastigotes and intracellular amastigotes of Leishmania (L.) chagasi, with 50% inhibitory concentration values of 81.2 and 21.5 muM, respectively. Nimodipine was about fourfold more effective than the standard pentavalent antimony against amastigotes and showed a Selectivity Index of 4.4 considering its mammalian cells toxicity. Leishmania (L.) amazonensis and Leishmania (L.) major promastigotes were also susceptible to nimodipine in a range concentration between 31 and 128 muM. Ultrastructural studies of L. (L.) chagasi revealed intense mitochondria damage and plasma membrane blebbing, resulting in a leishmanicidal effect as demonstrated by the lack of mitochondrial oxidative metabolism. The amastigote-killing effect suggests other mechanism than macrophage activation, as no upregulation of nitric oxide was seen. This calcium channel blocker is an effective in vitro antileishmanial compound and if adequately studied could be used as a novel drug candidate or as a novel drug lead compound for drug design studies against leishmaniasis.

Cytotoxicity of three new triazolo-pyrimidine derivatives against the plant trypanosomatid: Phytomonas sp. isolated from Euphorbia characias.

PubMed

Magán, Rosa; Marín, Clotilde; Salas, Juan M; Barrera-Pérez, Mario; Rosales, Maria J; Sánchez-Moreno, Manuel

2004-10-01

There is no effective chemotherapy against diseases caused by Phytomonas sp., a plant trypanosomatid responsible for economic losses in major crops. We tested three triazolo-pyrimidine complexes [two with Pt(II), and another with Ru(III)] against promastigotes of Phytomonas sp. isolated from Euphorbia characias. The incorporation of radiolabelled precursors, ultrastructural alterations and changes in the pattern of metabolite excretion were examined. Different degrees of toxicity were found for each complex: the platinum compound showed an inhibition effect on nucleic acid synthesis, provoking alterations on the levels of mitochondria, nucleus and glycosomes. These results, together with others reported previously in our laboratory about the activity of pyrimidine derivatives, reflect the potential of these compounds as agents in the treatment of Phytomonas sp.

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.

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.

Abnormalities of keratinocyte maturation and differentiation in keratosis palmoplantaris striata. Immunohistochemical and ultrastructural study before and during etretinate therapy.

PubMed

Fartasch, M; Vigneswaran, N; Diepgen, T L; Hornstein, O P

1990-06-01

Keratoderma striatum (Brünauer-Fuhs type) with linear keratotic elevations on the palms and small islets (areata form) on the soles is a rare form of palmoplantar keratoderma (PPK). An immunohistochemical and ultrastructural study has been performed to characterize the altered keratinization and maturation patterns in this disease before and during complete clinical remission on therapy with etretinate. Anticytokeratin antibody KL1 showed no significant difference in reaction pattern either between healthy controls and PPK or following therapy. Earlier expression of both filaggrin and involucrin was found in PPK in comparison with the controls. During etretinate therapy the filaggrin pattern returned to normal, whereas the altered involucrin pattern was not influenced. Ultrastructural investigations before treatment revealed tightly packed tonofibrils (TF) and large masses of keratohyalin (KH) granules with abnormal configuration. During therapy the TF and KH granules were reduced in number and size. KH granules now showed frayed borders. Moreover, a transitional cell zone, focal parakeratosis with lipid droplets, and dyskeratotic cells became apparent. The normalization of filaggrin pattern accompanying the clinical remission of these lesions implies a role of this keratinocyte differentiation protein in the pathogenesis of these lesions. Since etretinate is assumed to act at a very late stage of epidermal differentiation, there was no influence on the altered expression of involucrin during etretinate therapy. Despite the clinical remission, fine structural abnormalities persisted, indicating that the deviations from the normal keratinocyte differentiation program in PKK occur very early.

Anatomy, Ultrastructure and Chemical Composition of Food Bodies of Hovenia dulcis (Rhamnaceae)

PubMed Central

Buono, Rafael Andrade; de Oliveira, Alaíde Braga; Paiva, Elder Antonio Sousa

2008-01-01

Background and Aims Food bodies (FBs) are structures that promote mutualism between plants and ants, which help protect them against herbivores. The present study aims to describe the anatomical organization, ultrastructure and chemical composition of the FBs in Hovenia dulcis, which represent the first structures of this type described in Rhamnaceae. Methods Leaves in various stages of development were collected and fixed for examination under light, transmission and scanning electron microscopy. Samples of FBs were subjected to chemical analysis using thin-layer chromatography and nuclear magnetic resonance of 1H and 13C. Key Results The FBs vary from globose to conical and are restricted to the abaxial leaf surface, having a mixed origin, including epidermis and parenchyma. The FB epidermis is uniseriate, slightly pilose and has a thin cuticle. The epidermal cells are vacuolated and pigments or food reserves are absent. The parenchyma cells of immature FBs have dense cytoplasm showing mitochondria, endoplasmic reticulum and plastids. Mature FB cells store oils, which are free in the cytosol and occupy a large portion of the cell lumen. In these cells the plastids accumulate starch. Conclusions The lipids present in FBs are glycerin esters characteristic of plant energy reserves. Ants were observed collecting these FBs, which allows us to infer that these structures mediate plant–ant interactions and can help protect the young plants against herbivores, as these structures are prevalent at this developmental stage. PMID:18413656

Changes in ultrastructure and expression of steroidogenic factor-1 in ovaries of zebrafish Danio rerio exposed to glyphosate.

PubMed

Armiliato, Neide; Ammar, Dib; Nezzi, Luciane; Straliotto, Marcos; Muller, Yara M R; Nazari, Evelise M

2014-01-01

Glyphosate is a broad-spectrum organophosphate (OP) herbicide, highly soluble in water, and when applied in terrestrial systems it penetrates into soil, eventually reaching the aquatic community and affecting nontarget organisms. The aim of this study was to evaluate the toxicity of glyphosate on ovaries of zebrafish (Danio rerio). Ovaries (n = 18 per triplicate) were exposed to 65 μg/L of glyphosate [N-(phosphonomethyl) glycine] for 15 d. This concentration was determined according to Resolution 357/2005/CONAMA/Brazil, which establishes the permissible concentration of glyphosate in Brazilian inland waters. Nonexposed ovaries (n = 18 per triplicate) were used as control. Subsequently, morphology and expression of steroidogenic factor-1 (SF-1) of exposed and nonexposed ovaries was determined. No apparent changes were noted in general morphology of exposed and nonexposed ovaries. However, a significant increase in diameter of oocytes was observed after exposure to glyphosate. When ovarian ultrastructure was examined the presence of concentric membranes, appearing as myelin-like structures, associated with the external membranes of mitochondria and with yolk granules was found. After glyphosate exposure, immunohistochemistry and immunoblotting revealed greater expression of SF-1 in the oocytes, which suggests a relationship between oocyte growth and SF-1 expression. These subtle adverse effects of glyphosate on oocytes raised a potential concern for fish reproduction. These results contribute to understanding glyphosate-induced toxicity to nontarget organisms, showing subcellular and molecular impairments that may affect reproduction in +female fish.

A detailed microscopic study of the changes in the aorta of experimental model of postmenopausal rats fed with repeatedly heated palm oil.

PubMed

Adam, Siti Khadijah; Das, Srijit; Jaarin, Kamsiah

2009-06-01

Hypercholesterolaemia, increase in lipid peroxidation and hyperhomocysteinaemia may contribute to the pathogenesis of atherosclerosis. This study was performed to examine the effects of repeatedly heated palm oil mixed with 2% cholesterol diet on atherosclerosis in oestrogen-deficient postmenopausal rats. Ovariectomy causes disruption of tunica intima layer of the rat aorta simulating a postmenopausal condition in females. Twenty-four ovariectomized female Sprague-Dawley rats were divided into four groups. The control group received 2% cholesterol diet without palm oil. A diet with 2% cholesterol content fortified with fresh, once-heated and five-times-heated palm oil was given to the other treatment groups. The rats were sacrificed at the end of 4 months of study and the aortic arch tissue was processed for histomorphometry and electron microscopy. On observation, there was disruption of the intimal layer of the ovariectomized rat aorta. There was no obvious ultrastructural change in the aorta of the rats fed with fresh palm oil. The ultrastructural changes were minimal with once-heated palm oil, in which there was a focal disruption of the endothelial layer. The focal disruption was more pronounced with five-times-heated palm oil. The results of this study show that the ingestion of fresh palm oil may have a protective effect on the aorta but such a protective action may be lost when the palm oil is repeatedly heated. The study may be clinically important for all postmenopausal women who are susceptible to atherosclerosis.

Morphophysiology and ultrastructure of the male reproductive accessory glands of the bats Carollia perspicillata, Glossophaga soricina and Phyllostomus discolor (Chiroptera: Phyllostomidae).

PubMed

Martins, Fabiane F; Beguelini, Mateus R; Puga, Cintia C I; Morielle-Versute, Eliana; Vilamaior, Patricia S L; Taboga, Sebastião R

2016-07-01

The male reproductive accessory glands (RAGs) are important organs that contribute to the secretion of different substances that composed the ejaculate. Despite this important function, their composition, anatomy and function vary widely between species. Thus, the RAGs of three species of phyllostomid bats were morphologically and ultrastructurally characterized and compared in this study. The RAGs of the three analyzed species are composed of a prostate and a pair of bulbourethral glands (BG). In all species, the prostate is composed of three well-defined regions (ventral, dorsolateral and dorsal regions). The ventral region showed an atypical epithelium (undefined) with no obvious cellular limits and a holocrine PAS-positive secretion. The dorsolateral region of Carollia perspicillata and Phyllostomus discolor showed a pseudostratified cubic morphology, and that from Glossophaga soricina had a columnar morphology endowed with cytoplasmic projections and stereocilia. The dorsal region of the three analyzed species is composed of a pseudostratified columnar epithelium endowed with stereocilia; however, G. soricina also presented cytoplasmic projections in the apical portions of the secretory cells similar to those in the dorsolateral region. The BG of the three analyzed species are composed of a pseudostratified columnar epithelium including basal and PAS-positive secretory cells. In conclusion, this study morphologically and ultrastructurally characterized the RAGs of three species of phyllostomid bats, demonstrating the presence of a novel third prostatic region in species of this family. The results also showed the absence of seminal vesicles and ampullary glands, and better characterized the holocrine pattern of the prostatic ventral region, which is unique to bats. Copyright © 2016 Elsevier GmbH. All rights reserved.

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.

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

Diagnosis of electrocution: The application of scanning electron microscope and energy-dispersive X-ray spectroscopy in five cases.

PubMed

Visonà, S D; Chen, Y; Bernardi, P; Andrello, L; Osculati, A

2018-03-01

Deaths from electricity, generally, do not have specific findings at the autopsy. The diagnosis is commonly based on the circumstances of the death and the morphologic findings, above all the current mark. Yet, the skin injury due to an electrocution and other kinds of thermal injuries often cannot be differentiated with certainty. Therefore, there is a great interest in finding specific markers of electrocution. The search for the metallization of the skin through Scanning Electron Microscope equipped with Energy Dispersive X-Ray Spectroscopy (EDS) probe is of special importance in order to achieve a definite diagnosis in case of suspected electrocution. We selected five cases in which the electrocution was extremely likely considering the circumstances of the death. In each case a forensic autopsy was performed. Then, the skin specimens were stained with Hematoxylin Eosin and Perls. On the other hand, the skin lesions were examined with a scanning electron microscope equipped with EDS probe in order to evaluate the morphological ultrastructural features and the presence of deposits on the surface of the skin. The typical skin injury of the electrocution (current mark) were macroscopically detected in all of the cases. The microscopic examination of the skin lesions revealed the typical spherical vacuoles in the horny layer and, in the epidermis, the elongation of the cell nuclei as well as necrosis. Perls staining was negative in 4 out 6 cases. Ultrastructural morphology revealed the evident vacuolization of the horny layer, elongation of epidermic cells, coagulation of the elastic fibers. In the specimens collected from the site of contact with the conductor of case 1 and 2, the presence of the Kα peaks of iron was detected. In the corresponding specimens taken from cases 2, 4, 5 the microanalysis showed the Kα peaks of titanium. In case 3, titanium and carbon were found. In the suspicion of electrocution, the integrated use of different tools is recommended, including macroscopic observation, H&E staining, iron-specific staining, scanning electron microscopy and EDS microanalysis. Only the careful interpretation of the results provided by all these methods can allow the pathologist to correctly identify the cause of the death. Particularly, the present study suggests that the microanalysis (SEM-EDS) represents a very useful tool for the diagnosis of electrocution, allowing the detection and the identification of the metals embedded in the skin and their evaluation in the context of the ultrastructural morphology. Copyright © 2018. Published by Elsevier B.V.

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

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.

Ultrastructural basis for the efficiency of an ileal orthotopic neobladder 27 years after surgery.

PubMed

Orlandini, G; Guizzardi, S; Ferretti, S; Simonazzi, M; Bucci, G; Gatti, R

2002-01-01

The morphological and functional basis of the excellent clinical outcome of ileal orthotopic neobladders are largely unknown. Only long-term follow-up studies will provide an adequate answer to this unsettled question. We have studied a patient who underwent this type of surgery over 27 years ago. Besides an important secretive adaptation we have found, at the ultrastructural level, that the monolayered epithelium does not show signs of true metaplasia and that changes had occurred in the intercellular junctions, namely that desmosomes are significantly increased. Although limited to a single case, these features, if confirmed by further observations, suggest a working hypothesis for the understanding of the definitive phenotypic adaptation of the ileal epithelium to the new aggressive environment. Copyright 2002 S. Karger AG, Basel

Reissner's membrane and the spiral ligament in normal rats and those treated with ethacrynic acid

NASA Technical Reports Server (NTRS)

Ross, M. D.

1981-01-01

A description is presented of recent ultrastructural findings in Reissner's membrane and the spiral ligament in rats treated daily with ethacrynic acid during the 2nd and 3rd weeks of postnatal life, a period of final maturation of the inner ear and its fluids. A distension of Reissner's membrane in every cochlear turn, indicative of mild endolymphatic hydrops, was found to occur in animals that received a higher dose of ethacrynic acid. Ultrastructurally, the cytoplasm of the epithelial cells of Reissner's membrane showed increased electron density after treatment with ethacrynic acid. This increase was most pronounced in animals treated with a greater quantity of the drug. The epithelial cells had similar ultracellular features throughout except that the cells were much thinner in the region of maximal distension.

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.

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

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.

Studies on the cellular and subcellular reactions in epidermis at irritant and allergic dermatitis.

PubMed

Lindberg, M

1982-01-01

To determine the cellular and subcellular reactions of keratinocytes at contact dermatitis, transmission electron microscopy was used in combination with energy dispersive X-ray microanalysis. Stereology and optical diffraction were used as complements to electron microscopy for studies of the effects of variations in the preparation technique on the ultrastructure of epidermis. The morphological effects of an increased hydration of epidermis were assessed by the use of occlusive patch tests. It was found that the relative volume of the epidermal intercellular space and the ultrastructure of the epidermal cells (keratinocytes and Langerhans' cells) were directly dependent on the osmolality of the fixative vehicle if glutaraldehyde was used as fixative. Cellular volume and morphology did also depend on the fixative used. Variations in the volume of the intercellular space were also detected when the water transport through epidermis was impaired by occlusive treatment. In normal epidermis prolonged fixation times (4 weeks) did not affect the morphology of the keratinocytes. However, if the structure and function of the keratinocytes were affected by the application of a irritant substance (DNCB), a loss of electron dense material from the cells was detected within 3 weeks. The ultrastructural changes in the keratinocytes at the irritant chromate and DNCB reactions were of a non-specific nature and are in accordance with the changes described for other irritant agents in the literature. A few cells with the features of apoptosis were recorded. The allergic chromate reaction was found to be a combination of the irritant reaction and a marked inflammatory response. To correlate the ultrastructural alterations in the keratinocytes with the functional state of the cells, X-ray microanalysis was used to determine the elemental redistribution occurring at the irritant DNCB reaction. The results of the X-ray microanalysis showed a good correlation between dose and time dependent effects and with the ultrastructural changes. Cell injury in the keratinocytes lead to decreases in the cellular content of phosphorous, potassium and magnesium and an increase of cellular calcium. Sodium, chloride, and sulphur were only moderately changed. A stimulation of the basal keratinocytes was detectable when a weak DNCB dose was applied to the skin.

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.

Detection of fibrils associated with Rickettsia rickettsii.

PubMed

Todd, W J; Burgdorfer, W; Wray, G P

1983-09-01

The ultrastructural appearance of the "halozone" formed at the interface between the spotted fever agent Rickettsia rickettsii and the cytoplasm of persistently infected cultured vole cells (Microtus pennsylvanicus) was studied by transmission electron microscopy. In sections of epoxy-embedded specimens stained with uranyl acetate and lead citrate, the halozone appeared clear and devoid of ultrastructural features. However, when unembedded preparations of whole infected cells were examined at 1,000 kV, fine structural features were observed within the halozone. These features, associated with the rickettsial outer membrane, were more clearly detectable when the infected cells were extracted with the detergent Triton X-100 before fixation. Under such conditions, long extensions of the rickettsial outer membrane, microfilament-like structures attached to that membrane, and extensive attachments between adjacent rickettsiae were seen. The fine structural features within the rickettsial halozone were also seen at 75 kV when unembedded sections were prepared from polyethylene glycol-embedded specimens. Thus, epoxy-embedding medium obscures the fine structural features within the halozone surrounding the rickettsiae in infected cells.

Detection of fibrils associated with Rickettsia rickettsii.

PubMed Central

Todd, W J; Burgdorfer, W; Wray, G P

1983-01-01

The ultrastructural appearance of the "halozone" formed at the interface between the spotted fever agent Rickettsia rickettsii and the cytoplasm of persistently infected cultured vole cells (Microtus pennsylvanicus) was studied by transmission electron microscopy. In sections of epoxy-embedded specimens stained with uranyl acetate and lead citrate, the halozone appeared clear and devoid of ultrastructural features. However, when unembedded preparations of whole infected cells were examined at 1,000 kV, fine structural features were observed within the halozone. These features, associated with the rickettsial outer membrane, were more clearly detectable when the infected cells were extracted with the detergent Triton X-100 before fixation. Under such conditions, long extensions of the rickettsial outer membrane, microfilament-like structures attached to that membrane, and extensive attachments between adjacent rickettsiae were seen. The fine structural features within the rickettsial halozone were also seen at 75 kV when unembedded sections were prepared from polyethylene glycol-embedded specimens. Thus, epoxy-embedding medium obscures the fine structural features within the halozone surrounding the rickettsiae in infected cells. Images PMID:6411620

Electron microscopy of vesicular-arbuscular mycorrhizae of yellow poplar. III Host-endophyte interactions during arbuscular development.

PubMed

Kinden, D A; Brown, M F

1975-12-01

Scanning- and transmission-electron microscopy were used to examine developing and mature functional arbuscules in mycorrhizal roots of yellow poplar. Arbuscules developed from intracellular hyphae which branched repeatedly upon penetration into the host cells. Intermediate and late stages of developemnt were characterized by the production of numerous, short, bifurcate hyphae throughout the arbuscule. Mature arbuscules exhibited a coralloid morphology which resulted in a considerable increase in the surface area of the endophyte exposed within the host cells. Distinctive ultrastructural features of arbuscular hyphae included osmiophilic walls, nuclei, abundant cytoplasm, glycogen, and numerous small vacuoles. All arbuscular components were enclosed by host wall material and cytoplasm during development and at maturity. In infected cells, host nuclei were enlarged and the cytoplasm associated with the arbuscular branches typically contained abundant mitochondria, endoplasmic reticulum, and proplastids. Ultrastructural observations suggested that nutrient transfer may be predominantly directed toward the fungal endophyte during arbuscular development and while mature arbuscules remain functional.

Vitamin E modifies the ultrastructure of testis and epididymis in mice exposed to lead intoxication.

PubMed

Fahim, Mohamed A; Tariq, Saeed; Adeghate, Ernest

2013-05-01

Lead (Pb) is known to cause abnormal function of several systems including the male reproductive system, where it has been shown to reduce sperm count. In order to examine the morphological basis of the reduction in sperm count and a possible effect of vitamin E, lead acetate (1 mg/kg body weight) was given to control and vitamin E-treated mice daily, intraperitoneally for 3 weeks. The testis and body of epididymis of the mice were subjected to electron microscopy study. Pb caused degenerative changes in spermatids inducing vacuolization and a reduction in the number of cytoplasmic organelles in Leydig cells. Pb also destroyed the stereocilia of epididymal epithelium. The addition of vitamin E ameliorated the severity of these morphological changes. In conclusion, Pb-induced reduction in sperm count may be due to changes in the ultrastructure of spermatids, epididymal epithelia and Leydig cells. These changes can be reduced by vitamin E. Copyright © 2012 Elsevier GmbH. All rights reserved.

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.

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 observation of the acid-base resistant zone of all-in-one adhesives using three different acid-base challenges.

PubMed

Tsujimoto, Miho; Nikaido, Toru; Inoue, Go; Sadr, Alireza; Tagami, Junji

2010-11-01

The aim of this study was to analyze the ultrastructure of the dentin-adhesive interface using two all-in-one adhesive systems (Clearfil Tri-S Bond, TB; Tokuyama Bond Force, BF) after different acid-base challenges. Three solutions were used as acidic solutions for the acid-base challenges: a demineralizing solution (DS), a phosphoric acid solution (PA), and a hydrochloric acid solution (HCl). After the acid-base challenges, the bonded interfaces were examined by scanning electron microscopy. Thickness of the acid-base resistant zone (ABRZ) created in PA and HCl was thinner than in DS for both adhesive systems. For BF adhesive, an eroded area was observed beneath the ABRZ after immersion in PA and HCl, but not in DS. Conversely for TB adhesive, the eroded area was observed only after immersion in PA. In conclusion, although the ABRZ was observed for both all-in-one adhesive systems, its morphological features were influenced by the ingredients of both the adhesive material and acidic solution.

[Ultrastructural changes in the MP3 neuron of the mollusk Lymnaea stagnalis after cryopreservation of the isolated brain].

PubMed

Dmitrieva, E V; Moshkov, D A; Gakhova, E N

2006-01-01

Investigation of a possibility of long-term storage of frozen (-196 degrees C) viable neurons and nervous tissue is one of the central present day problems. In this study ultrastructural changes in neurons of frozen-thawed snail brain were examined as a function of time. We studied the influence of cryopreservation, cryoprotectant (Me2SO), cooling to 4-6 degrees C, and a prolonged incubation in physiological solution at 4-6 degrees C on dictyosomes of Golgi apparatus, endoplasmic reticulum (ER) cisternae and mitochondria. It has been found that responses of these intracellular structures of cryopreserved neurons to the above influences are similar: dissociation of Golgi dictyosomes, swelling of endoplasmic reticulum cisternae and mitochondrial cristae. Both freezing-thawing and cryoprotectant were seen to cause an increase in the number of lysosomes, liposomes, myelin-like structures, and to form large vacuoles. The structural changes in molluscan neurons caused by cryopreservation with Me2SO (2 M) were reversible.

Effect of heat shock on ultrastructure and calcium distribution in Lavandula pinnata L. glandular trichomes.

PubMed

Huang, S S; Kirchoff, B K; Liao, J P

2013-02-01

The effects of heat shock (HS) on the ultrastructure and calcium distribution of Lavandula pinnata secretory trichomes are examined using transmission electron microscopy and potassium antimonate precipitation. After 48-h HS at 40°C, plastids become distorted and lack stroma and osmiophilic deposits, the cristae of the mitochondria become indistinct, the endoplasmic reticulum acquires a chain-like appearance with ribosomes prominently attached to the lamellae, and the plasma and organelle membranes become distorted. Heat shock is associated with a decrease in calcium precipitates in the trichomes, while the number of precipitates increases in the mesophyll cells. Prolonged exposure to elevated calcium levels may be toxic to the mesophyll cells, while the lack of calcium in the glands cell may deprive them of the normal protective advantages of elevated calcium levels. The inequality in calcium distribution may result not only from uptake from the transpiration stream, but also from redistribution of calcium from the trichomes to the mesophyll cells.

[Depiction of the structure of the vitreous body in horses without ocular diseases and in horses with equine recurrent uveitis (ERU) using transmission electron microscopy].

PubMed

Niedermaier, G; Wollanke, B; Hoffmann, R; Matiasek, K; Gerhards, H

2006-06-01

Neither the ultrastructure of the vitreous body from horses without ocular diseases, nor the pathomorphological changes in the vitreous body associated with equine recurrent uveitis (ERU) have been described. However, the vitreous body plays an important role in the pathogenesis of ERU. Ten vitreous body samples obtained from 5 horses without ocular disease, and 38 vitreous body samples from horses with ERU (collected during vitrectomy) were examined by transmission electron microscopy. The vitreous body samples of horses without ocular diseases were characterized by a loose network of unbranched fibrils 10-12 nm in width. In the vitreous body samples of horses with ERU numerous dense bundles of fibrils, mononuclear inflammatory cells and necrotic cells represent the destruction of the vitreous fibrillar network. In this study, equine vitreous body ultrastructure was described for the first time. Thus, demonstrating ultramorphologically, the clinically apparent changes of the vitreous body associated with ERU.

Desmograptus. micronematodes, a silurian dendroid graptolite, and its ultrastructure

USGS Publications Warehouse

Saunders, K.M.; Bates, D.E.B.; Kluessendorf, Joanne; Loydell, David K.; Mikulic, Donald G.

2009-01-01

Desmograptus micronematodes from Thornton quarry, Cook County, Illinois, USA, remarkably preserved in relief and encased in pyrite, is described. The internal details of the thecae, and of the stolon system, examined using the SEM, allow the reconstruction of the growth of a stipe. The stolons and stolonal nodes are formed of a dense crassal fabric, and are surrounded by a loose fabric of three-dimensional fibrils. The nodes have a complex structure of three boxes with proximal and distal nozzles. The base of a bitheca, and the base of each autothecal cup, has a central nozzle surrounded by a unique honeycomb fabric. The ultrastructure of the cortical fibrils, with their clockwise striations, is similar to that in Dendrograptus, and may be universal in the graptolites. The nodes of the stolon system appear identical to those of Acanthograptus and other dendroids, but differ from those of the extant hemichordate Rhabdopleura, which have only a diaphragm, and lack box structures. ?? The Palaeontological Association, 2009.

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 changes of goat corpus luteum during the estrous cycle.

PubMed

Jiang, Yi-Fan; Hsu, Meng-Chieh; Cheng, Chiung-Hsiang; Tsui, Kuan-Hao; Chiu, Chih-Hsien

2016-07-01

The present study was designed to study the ultrastructure of goat corpora lutea (CL, n=10) and structural changes as related to steroidogenic functions during the estrous cycle. The reproduction status of goats was estimated by analyzing serum progesterone concentrations. The CL at various stages was surgically collected. To characterize ultrastructural features associated with steroidogenesis, tissue and cellular structures were studied. Blood supplies were examined based on features of the endothelial cells and capillary structures in the CL. Activated endothelial cells and developing vessels were observed in the early stage, whereas mature endothelial cells, accumulating extracellular matrix fibers, and stabilized vessels were observed in the middle and late stages of assessment. In the late stage of assessment, shrunken goat luteal cells scattered around the capillaries were detected and formed circular regression areas. Features of autophagy and luteal cell apoptosis were noted. In large luteal cells, steroidogenic organelles were present, including microvillar channels, endoplasmic reticulum, and mitochondria. Conformational changes in the endoplasmic reticulum and increased mitochondria with tubular cristae were observed in the early-middle CL transitions. In contrast, mitochondria swelled and the cristae transformed to the lamellar type in the late stage, suggesting that organelle plasticity could contribute to steroidogenesis in goat CL. In conclusion, results suggest angiogenesis occurs in early developing CL and programmed cell death occurred in the late stage of CL assessment in the present study. Structures and quantiles of steroidogenic organelles are correlated with the steroidogenic functions in goats. Copyright © 2016 Elsevier B.V. All rights reserved.

Effect of water on nanomechanics of bone is different between tension and compression

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

Samuel, Jitin; Park, Jun-Sang; Almer, Jonathan

Water, an important constituent in bone, resides in different compartments in bone matrix and may impose significant effects on its bulk mechanical properties. However, a clear understanding of the mechanistic role of water in toughening bone is yet to emerge. To address this issue, this study used a progressive loading protocol, coupled with measurements of in situ mineral and collagen fibril deformations using synchrotron X-ray diffraction techniques. Using this unique approach, the contribution of water to the ultrastructural behavior of bone was examined by testing bone specimens in different loading modes (tension and compression) and hydration states (wet and dehydrated).more » The results indicated that the effect of water on the mechanical behavior of mineral and collagen phases at the ultrastructural level was loading mode dependent and correlated with the bulk behavior of bone. Tensile loading elicited a transitional drop followed by an increase in load bearing by the mineral phase at the ultrastructural level, which was correlated with a strain hardening behavior of bone at the bulk level. Compression loading caused a continuous loss of load bearing by the mineral phase, which was reflected at the bulk level as a strain softening behavior. In addition, viscous strain relaxation and pre-strain reduction were observed in the mineral phase in the presence of water. Taken together, the results of this study suggest that water dictates the bulk behavior of bone by altering the interaction between mineral crystals and their surrounding matrix.« less

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

PubMed

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

2012-05-01

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

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

Protective effects of magnesium supplementation on metabolic energy derangements in lipopolysaccharide-induced cardiotoxicity in mice.

PubMed

Ahmed, Lamiaa A

2012-11-05

Metabolic derangements and bioenergetic failure are major contributors to sepsis-induced multiple organ dysfunctions. Due to the well known role of magnesium (Mg) as a cofactor in many enzymatic reactions that involve energy creation and utilization, the present investigation was directed to estimate the cardioprotective effect of Mg supplementation in lipopolysaccharide (LPS)-induced metabolic energy changes in mice. Oral doses of Mg aspartate (20 or 40 mg/kg) were administered once daily for 7 day. Mice were then subjected to a single intraperitoneal injection of LPS (2 mg/kg). Plasma was separated 3 h after LPS injection for determination of creatine kinase-MB activity. Animals were then sacrificed and the hearts were separated for estimation of tissue thiobarbituric acid reactive substances, reduced glutathione, lactate, pyruvate, adenine nucleotides, creatine phosphate and cardiac Na(+),K(+)-ATPase activity. Finally, electron microscopic examination was performed to visualize the protective effects of Mg pretreatment on mitochondrial ultrastructure. In general, the higher dose of Mg was more effective than the lower dose in ameliorating creatine kinase-MB elevation and the state of oxidative stress, lactate accumulation, pyruvate reduction as well as preserving creatine phosphate, adenine nucleotides and Na(+),K(+)-ATPase activity. Moreover, the higher dose of Mg provided a significant cardioprotection against the mitochondrial ultrastructural changes. Mg therapy can afford a significant protection against metabolic energy derangements and mitochondrial ultrastructural changes induced by LPS cardiotoxicity in mice. Copyright © 2012 Elsevier B.V. All rights reserved.

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.

DNA damage in lead-exposed hepatocytes: coexistence of apoptosis and necrosis?

PubMed

Narayana, Kilarkaje; Raghupathy, Raj

2012-04-01

The aim of the present study was to investigate the coexistence of oxidative DNA damage and apoptosis- and necrosis-related DNA damage, and to correlate with ultrastructural changes in hepatocyte nuclei in the lead-nitrate-exposed liver. Adult male Wistar rats were exposed to 0, 0.5, and 1% lead nitrate for 60 days, and the livers were sampled the next day. Ultrastructurally, hepatocyte nuclei showed no apoptosis-related morphological changes, but showed necrotic changes. Competitive enzyme-linked immunosorbent assay showed no change in 8-oxo-dG activity (P > 0.05), but immunohistochemistry showed its localization in hepatocytes, Kupffer cells, endothelium, and bile ductule epithelium. TUNEL-labeled DNA breaks presenting 3'-OH ends increased in hepatocytes in all functional zones of the portal acini and bile ductule epithelium (zones I>III>II). In situ oligo ligation revealed the existence of DNA breaks bearing duplex 3' overhangs and 5' P-blunt ends in hepatocytes of all functional zones and bile ductule epithelium. In conclusion, both apoptosis- and necrosis-related DNA damage coexist without significant oxidative DNA damage. Hepatocytes display changes related to necrosis, but not those related to apoptosis.

Oxidative Weathering and Microbial Diversity of an Inactive Seafloor Hydrothermal Sulfide Chimney

PubMed Central

Li, Jiangtao; Cui, Jiamei; Yang, Qunhui; Cui, Guojie; Wei, Bingbing; Wu, Zijun; Wang, Yong; Zhou, Huaiyang

2017-01-01

When its hydrothermal supply ceases, hydrothermal sulfide chimneys become inactive and commonly experience oxidative weathering on the seafloor. However, little is known about the oxidative weathering of inactive sulfide chimneys, nor about associated microbial community structures and their succession during this weathering process. In this work, an inactive sulfide chimney and a young chimney in the early sulfate stage of formation were collected from the Main Endeavor Field of the Juan de Fuca Ridge. To assess oxidative weathering, the ultrastructures of secondary alteration products accumulating on the chimney surface were examined and the presence of possible Fe-oxidizing bacteria (FeOB) was investigated. The results of ultrastructure observation revealed that FeOB-associated ultrastructures with indicative morphologies were abundantly present. Iron oxidizers primarily consisted of members closely related to Gallionella spp. and Mariprofundus spp., indicating Fe-oxidizing species likely promote the oxidative weathering of inactive sulfide chimneys. Abiotic accumulation of Fe-rich substances further indicates that oxidative weathering is a complex, dynamic process, alternately controlled by FeOB and by abiotic oxidization. Although hydrothermal fluid flow had ceased, inactive chimneys still accommodate an abundant and diverse microbiome whose microbial composition and metabolic potential dramatically differ from their counterparts at active vents. Bacterial lineages within current inactive chimney are dominated by members of α-, δ-, and γ-Proteobacteria and they are deduced to be closely involved in a diverse set of geochemical processes including iron oxidation, nitrogen fixation, ammonia oxidation and denitrification. At last, by examining microbial communities within hydrothermal chimneys at different formation stages, a general microbial community succession can be deduced from early formation stages of a sulfate chimney to actively mature sulfide structures, and then to the final inactive altered sulfide chimney. Our findings provide valuable insights into the microbe-involved oxidative weathering process and into microbial succession occurring at inactive hydrothermal sulfide chimney after high-temperature hydrothermal fluids have ceased venting. PMID:28785251

[Effect of electroacupuncture on the behavior and hippocampal ultrastructure in APP 695 V 717 I transgenic mice].

PubMed

Xue, Wei-Guo; Ge, Gui-Ling; Zhang, Zhong; Xu, Hong; Bai, Li-Min

2009-10-01

To investigate the ultrastructural basis underlying electroacupuncture (EA) induced improvement of Alzheimer disease (AD) in transgenic mice. Twelve APP 695 V 717 I transgenic mice were randomly divided into model group and EA group; and other 6 negative transgenic mice (C 57 BL/6 J) were made up of normal control group. After 3 months treatment by EA (15 min per other day, 2 Hz/100 Hz, 3-4 mA) applied to "Baihui" (GV 20) and "Yongquan" (KI 1), the learning and memory ability of mice was measured by Lashley III water maze test, and the ultrastructural changes of hippocampal CA 1 region was observed by electronic microscopy. The swimming escape latency and the number of navigating errors (dead-end forward swimming) in model group were significantly longer and more than those in normal control group (P < 0.05); and those in EA group were considerably shorter and fewer than those in model group (P < 0.05), suggesting an improvement of learning-memory ability after EA. Comparison of the ultrastructure of the neurons in the hippocampal CA 1 region showed swelling of the mitochondria, broken or disappearance of the mitochondrial cristae, degeneration of the synapses, breakage and vague outline of the basement membrane of the blood capillaries in mice of model group; and basically distinct outline of the mitochondrial cristae and microvessels, and more synaptic vesicles in EA group. EA may effectively improve the learning-memory capacity of the APP transgenic AD mice and alleviate the pathological changes of neurons of the hippocampal CA 1 region, which may be one of the mechanisms underlying the improvement of AD by EA.

[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 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

Anti-inflammatory and ultrastructural effects of Turkish propolis in a rat model of endotoxin-induced uveitis.

PubMed

Ertürküner, Salime Pelin; Yaprak Saraç, Elif; Göçmez, Semil Selcen; Ekmekçi, Hakan; Öztürk, Zeynep Banu; Seçkin, İsmail; Sever, Özkan; Keskinbora, Kadircan

2016-01-01

Experimental animal models of acute uveitis, an inflammatory eye disease, can be established via endotoxin-induced inflammation. Propolis, a natural substance collected by honeybees from buds and tree exudates, has antioxidant, antibacterial, antiviral, and anti-inflammatory effects. We investigated the effects of propolis, obtained from the Sakarya province of Turkey, on endotoxin-induced uveitis using immunohistochemical, ultrastructural, and biochemical approaches. Male Wistar albino rats (n = 6/group) received intraperitoneal (ip) lipopolysaccharide (LPS) endotoxin (150 μg/kg) followed by aqueous extract of propolis (50 mg/kg ip) or vehicle; two additional groups received either saline (control) or propolis only. After 24 h, aqueous humor (AH) was collected from both eyes of each animal for analysis of tumor necrosis factor-α (TNF-α) and hypoxia-inducible factor-1α (HIF-1α). Right eyeballs were paraffin-embedded for immunohistochemical staining of nuclear factor κB (NF-κB)/p65 and left eyeballs were araldite-embedded for ultrastructural analysis. Treatment of LPS-induced uveitis with propolis significantly reduced ciliary body NF-κB/p65 immunoreactivity and AH levels of HIF-1α and TNF-α. Ultrastructural analysis showed fewer vacuoles and reduced mitochondrial degeneration in the retinal pigment epithelium, as compared to the uveitis group. The intercellular spaces of the inner nuclear layer and outer limiting membrane were comparable with those of the control group; no polymorphonuclear cells or stasis was observed in intravascular or extravascular spaces. This is the first report demonstrating an anti-inflammatory effect of Turkish propolis in a rat model of LPS-induced acute uveitis, suggesting a therapeutic potential of propolis for the treatment of inflammatory ophthalmic diseases.

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.

Ultrastructure of the salivary glands in Lithobius forficatus (Myriapoda, Chilopoda, Lithobiidae) according to seasonal and circadian rhythms.

PubMed

Kamińska, K; Włodarczyk, A; Sonakowska, L; Ostróżka, A; Marchewka, A; Rost-Roszkowska, M

2016-11-01

The salivary glands (mandibular epidermal glands) of adult males and females of Lithobius forficatus (Myriapoda, Chilopoda) were isolated during spring, summer and autumn. In addition, the organs were isolated at different times of the day - at about 12:00 (noon) and about 00:00 (midnight). The ultrastructure of these organs depending on seasonal and circadian rhythms was analyzed using transmission and scanning electron microscopy and histochemical methods. The paired salivary glands of L. forficatus are situated in the vicinity of the foregut and they are formed by numerous acini that are surrounded by the fat body, hemocytes and tracheolae. The salivary glands are composed of a terminal acinar component and a system of tubular ducts that are lined with a cuticle. The glandular part is composed of secretory epithelial cells that are at various stages of their secretory activity. The saliva that is produced by the secretory cells of the acini is secreted into the salivary ducts, which are lined with a simple epithelium that is based on the non-cellular basal lamina. The ultrastructural variations suggest that salivary glands function differently depending on seasonal rhythms and prepare the animal for overwintering. Therefore, the salivary glands of the centipedes that were analyzed participate in the accumulation of proteins, lipids and polysaccharides during the spring, summer and autumn. Subtle differences in the ultrastructure of the secretory cells of the salivary glands during the circadian cycle must be related to the physiological reactions of the organism. The salivary ducts showed no differences in the specimens that were analyzed during the day/night cycle or during the seasonal cycle. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of aluminum in red spruce (Picea rubens) cell cultures: Cell growth and viability, mitochondrial activity, ultrastructure and potential sites of intracellular aluminum accumulation

Treesearch

Rakesh Minocha; Carolyn McQuattie; Wayne Fagerberg; Stephanie Long; Eun Woon Noh

2001-01-01

The effects of Al on red spruce (Picea rubens Sarg.) cell suspension cultures were examined using biochemical, stereo-logical and microscopic methods. Exposure to Al for 24-48 h resulted in a loss of cell viability, inhibition of growth and a significant decrease in mitochondrial activity. Soluble protein content increased in cells treated with Al....

An ultrastructural study of Paraphysoderma sedebokerense (Blastocladiomycota), an epibiotic parasite of microalgae.

PubMed

Letcher, Peter M; Lee, Philip A; Lopez, Salvador; Burnett, Micheal; McBride, Robert C; Powell, Martha J

2016-03-01

Successful algal cultivation for biofuel production is one path in the transition to a renewable energy economy. The green alga Scenedesmus dimorphus is a candidate for biofuel production, but is subject to parasitism and subsequent population crash when cultivated in open ponds. From an open pond cultivating S. dimorphus for biofuel production in New Mexico, USA, an amoeboid parasite was isolated, designated as isolate FD61, and its rDNA operon sequenced. A BLAST search for nuc 18S rDNA (18S) sequence similarity identified the parasite as Paraphysoderma sedebokerense (Blastocladiomycota). Here, we examine the ultrastructure of P. sedebokerense and compare it with that of a sister taxon, Physoderma maydis. The parasite has thin-walled vegetative sporangia and thick-walled resting sporangia. Our observations indicate that amoeboid swarmers are produced in the vegetative phase, while either amoeboid swarmers or zoospores are the product of meiosis in resting sporangia. Meiosis is confirmed by the presence of synaptonemal complexes in resting sporangia nuclei. Notably, P. sedebokerense has a Golgi apparatus with stacked cisternae, a feature reported for P. maydis, but which is absent in all other examined taxa in Blastocladiomycota. This report furthers our knowledge of the life cycle of P. sedebokerense. Copyright © 2015 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Differential diagnosis between mesothelioma and adenocarcinoma: a multimodal approach based on ultrastructure and immunocytochemistry

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

Bedrossian, C.W.; Bonsib, S.; Moran, C.

1992-05-01

Most compensations for asbestos-related deaths secondary to cancer center around mesothelioma and bronchogenic carcinoma. The differential diagnosis between mesothelioma and adenocarcinoma is a common and troublesome one, necessitating the correlation between clinical history, radiographic findings, and pathologic examination of tissues and cells. We describe a multimodal approach based on the use of routine and special stains, immunocytochemistry, and electron microscopy for distinguishing between mesothelioma and adenocarcinoma. Once a malignant diagnosis is arrived at by careful pathological examination, the tumor is classified as mesothelioma if mesothelial cells are identified as the constituent cells of the neoplasm. Mesothelial cells are recognized bymore » (1) their main ultrastructural features: slender and elongated microvilli, abundant intermediate filaments, and lacking secretory granules; and (2) their characteristic immunocytochemical reactivity: positivity for cytokeratin, EMA, and vimentin, and negativity for carcinoembryonic antigen (CEA), B72-3, Leu-M1, and other gland-cell markers. A variety of methods have been attempted in an effort to distinguish between reactive and malignant mesothelial cells. In practice, however, such distinction depends more on experience and expertise than in any fool-proof ancillary tests. A number of these tests are discussed along with the illustration of classical and unusual examples of mesothelioma and other pleural tumors.« less

The ultrastructural research of liver in experimental obstructive jaundice and effect of honey.

PubMed

Kilicoglu, Bulent; Gencay, Cem; Kismet, Kemal; Serin Kilicoglu, Sibel; Erguder, Imge; Erel, Serap; Sunay, Asli Elif; Erdemli, Esra; Durak, Ilker; Akkus, Mehmet Ali

2008-02-01

To examine the effects of honey on oxidative stress and apoptosis in experimental obstructive jaundice model. Thirty rats were divided into 3 groups: group I, sham-operated; group II, ligation and division of the common bile duct (BDL); group III, BDL followed by oral supplementation of honey 10 g/kg/d. Liver samples were examined under light microscope and transmission electron microscope. Hepatocyte apoptosis was quantitated using the terminal deoxy-nucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) assay. Plasma and blood malondialdehyde (MDA) and glutation activities were measured for determining the oxidative stress. The liver levels of MDA and GSH were significantly different between the honey and BDL groups (P = .006 and .001, respectively). However, there was no significant difference between the plasma MDA and GSH levels of these groups (P > .05). In group III, significant reductions in the size of enlarged hepatocytes and the edema were demonstrated. The dilatation of the bile canaliculi dramatically turned to original dimention. By TUNEL assay, it was shown that administration of honey decreased the number of apoptotic cells. In the present study, we found that honey diminished the negative effects of BDL on the hepatic ultrastructure. We conclude that this effect might be due to its antioxidant and anti-inflammatory activities.

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.

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.

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

Immunohistochemical and ultrastructural characteristics of interstitial cells of Cajal in the rabbit duodenum. Presence of a single cilium

PubMed Central

Junquera, Concepción; Martínez-Ciriano, Carmen; Castiella, Tomás; Serrano, Pedro; Azanza, María Jesús; Ramón y Cajal Junquera, Santiago

2007-01-01

Abstract Santiago Ramón y Cajal discovered a new type of cell related to the myenteric plexus and also to the smooth muscle cells of the circular muscle layer of the intestine. Based on their morphology, relationships and staining characteristics, he considered these cells as primitive neurons. One century later, despite major improvements in cell biology, the interstitial cells of Cajal (ICCs) are still controversial for many researchers. The aim of study was to perform an immunohistochemical and ultrastructural characterization of the ICCs in the rabbit duo-denum. We have found interstitial cells that are positive for c-Kit, CD34 and nestin and are also positive for Ki67 protein, tightly associated with somatic cell proliferation. By means of electron microscopy, we describe ICCs around enteric ganglia. They present triangular or spindle forms and a very voluminous nucleus with scarce per-inuclear chromatin surrounded by a thin perinuclear cytoplasm that expands with long cytoplasmic processes. ICC processes penetrate among the smooth muscle cells and couple with the processes of other ICCs located in the connective tissue of the circular muscle layer and establish a three-dimensional network. Intercellular con-tacts by means of gap-like junctions are frequent. ICCs also establish gap-like junctions with smooth muscle cells. We also observe a population of interstitial cells of stellate morphology in the connective tissue that sur-rounds the muscle bundles in the circular muscle layer, usually close to nervous trunks. These cells establish different types of contacts with the muscle cells around them. In addition, the presence of a single cilium show-ing a structure 9 + 0 in an ICC is demonstrated for the first time. In conclusion, we report positive staining c-kit, CD34, nestin and Ki 67. ICCs fulfilled the usual transmission electron microscopy (TEM) criteria. A new ultrastructural characteristic of at least some ICCs is demonstrated: the presence of a single cilium. Some populations of ICCs in the rabbit duodenum present certain immunohistochemical and ultrastructural characteristics that often are present in progenitor cells. PMID:17760839

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.

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.

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.

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.

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.

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

PubMed

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

2016-09-01

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

Synaptic pathology in the cerebellar dentate nucleus in chronic multiple sclerosis.

PubMed

Albert, Monika; Barrantes-Freer, Alonso; Lohrberg, Melanie; Antel, Jack P; Prineas, John W; Palkovits, Miklós; Wolff, Joachim R; Brück, Wolfgang; Stadelmann, Christine

2017-11-01

In multiple sclerosis, cerebellar symptoms are associated with clinical impairment and an increased likelihood of progressive course. Cortical atrophy and synaptic dysfunction play a prominent role in cerebellar pathology and although the dentate nucleus is a predilection site for lesion development, structural synaptic changes in this region remain largely unexplored. Moreover, the mechanisms leading to synaptic dysfunction have not yet been investigated at an ultrastructural level in multiple sclerosis. Here, we report on synaptic changes of dentate nuclei in post-mortem cerebella of 16 multiple sclerosis patients and eight controls at the histological level as well as an electron microscopy evaluation of afferent synapses of the cerebellar dentate and pontine nuclei of one multiple sclerosis patient and one control. We found a significant reduction of afferent dentate synapses in multiple sclerosis, irrespective of the presence of demyelination, and a close relationship between glial processes and dentate synapses. Ultrastructurally, we show autophagosomes containing degradation products of synaptic vesicles within dendrites, residual bodies within intact-appearing axons and free postsynaptic densities opposed to astrocytic appendages. Our study demonstrates loss of dentate afferent synapses and provides, for the first time, ultrastructural evidence pointing towards neuron-autonomous and neuroglia-mediated mechanisms of synaptic degradation in chronic multiple sclerosis. © 2016 International Society of Neuropathology.

Ultrastructural Analysis of In Vivo Hypoglycemiant Effect of Two Polyoxometalates in Rats with Streptozotocin-Induced Diabetes.

PubMed

Bâlici, Ştefana; Wankeu-Nya, Modeste; Rusu, Dan; Nicula, Gheorghe Z; Rusu, Mariana; Florea, Adrian; Matei, Horea

2015-10-01

Two polyoxometalates (POMs), synthesized through a self-assembling method, were used in the treatment of streptozotocin (STZ)-induced diabetic rats. One of these nanocompounds [tris(vanadyl)-substituted tungsto-antimonate(III)-anions—POM1] was previously described in the literature, whereas the second [tris-butyltin-21-tungsto-9-antimonate(III)-anions—POM2], was prepared by us based on our original formula. In rats with STZ-induced diabetes treated with POMs (up to a cumulative dose of 4 mg/kg bodyweight at the end of the treatments), statistically significant reduced levels of blood glucose were measured after 3 weeks, as compared with the diabetic control groups (DCGs). Ultrastructural analysis of pancreatic β-cells (including the mean diameter of secretory vesicles and of their insulin granules) in the treated diabetic rats proved the POMs contribute to limitation of cellular degeneration triggered by STZ, as well as to the presence of increased amounts of insulin-containing vesicles as compared with the DCG. The two POMs also showed hepatoprotective properties when ultrastructural aspects of hepatocytes in the experimental groups of rats were studied. Based on our in vivo studies, we concluded that the two POMs tested achieved hypoglycemiant effects by preventing STZ-triggered apoptosis of pancreatic β-cells and stimulation of insulin synthesis.

[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.

Ultrastructure of the renal juxtaglomerular complex and peripolar cells in the axolotl (Ambystoma mexicanum) and toad (Bufo marinus).

PubMed Central

Hanner, R H; Ryan, G B

1980-01-01

Renal juxtaglomerular regions were examined in the axolotl (Ambystoma mexicanum and toad (Bufo marinus). Prominent granulated peripolar epithelial cells were found surrounding the origin of the glomerular tuft in the axolotl. These cells resembled the peripolar cells recently discovered in mammalian species. They contained multiple electron-dense cytoplasmic granules, some of which showed a paracrystalline substructure and signs of exocytoxic activity. Such cells were difficult to find and smaller in the toad. In contrast, granulated juxtaglomerular arteriolar myoephithelial cells were much more readily found and larger in the toad than in the axolotl. No consistent differences were noted in juxtaglomerular cells or their granules in response to changes in environmental chloride concentration. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:7410189

Ranavirus-associated mass mortality in wild amphibians, the Netherlands, 2010: a first report.

PubMed

Kik, Marja; Martel, An; Sluijs, Annemarieke Spitzen-van der; Pasmans, Frank; Wohlsein, Peter; Gröne, Andrea; Rijks, Jolianne M

2011-11-01

In 2010, a mass die-off of over 1000 wild water frogs (Pelophylax spp.) and at least 10 common newts (Lissotriton vulgaris) occurred in a pond in The Netherlands. Haemorrhagic disease with hepatomegaly and splenomegaly was evident. Microscopically, multiple organs presented cells with multifocal intracytoplasmic inclusion bodies, in which ranavirus-like particles were demonstrated ultrastructurally. All specimens examined tested positive for ranavirus by PCR. The sequence obtained showed a 100% identity with the one deposited for common midwife toad virus (CMTV). This is the first report of ranavirus-associated mortality in wild amphibian populations in The Netherlands. It is also the first time CMTV or a CMTV-like virus has been reported in these two species in the adult stage and outside of Spain. Copyright © 2011 Elsevier Ltd. All rights reserved.

Egg structure and ultrastructure of Paterdecolyus yanbarensis (Insecta, Orthoptera, Anostostomatidae, Anabropsinae).

PubMed

Mashimo, Yuta; Fukui, Makiko; Machida, Ryuichiro

2016-11-01

The egg structure of Paterdecolyus yanbarensis was examined using light, scanning electron and transmission electron microscopy. The egg surface shows a distinct honeycomb pattern formed by exochorionic ridges. Several micropyles are clustered on the ventral side of the egg. The egg membrane is composed of an exochorion penetrated with numerous aeropyles, an endochorion, and an extremely thin vitelline membrane. The endochorion is thickened at the posterior egg pole, probably associated with water absorption. A comparison of egg structure among Orthoptera revealed that the micropylar distribution pattern is conserved in Ensifera and Caelifera and might be regarded as a groundplan feature for each group; in Ensifera, multiple micropyles are clustered on the ventral side of the egg, whereas in Caelifera, micropyles are arranged circularly around the posterior pole of the egg. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ultrastructure of Lymphocystis Virus

PubMed Central

Zwillenberg, Lutz O.; Wolf, Ken

1968-01-01

Lymphocystis virus obtained from bluegills (Lepomis macrochirus) was cultured in the permanent bluegill cell line BF-2 and examined by electron microscopy in ultrathin sections of cell cultures and in negative-contrast preparations from cells and from centrifuged culture medium. According to negative-contrast preparations, the icosahedral virions have an overall diameter close to but not exceeding 300 mμ. Delicate filaments seem to issue from the vertices. In collapsed virions, an ordered array of morphological units was seen. Positively contrasted virions in ultrathin sections show a shell with three dark (heavy metal-stained) layers alternating with and separated by two clear layers. The acquisition of an additional outer membrane during release from the cell, as found in African swine fever virus, was never seen. Morphologically, lymphocystis virus is considered to be closely related to Tipula iridescent virus. Images PMID:4986903

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.

[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.

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.

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.

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.

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.

A morphometric analysis of cellular differentiation in caps of primary and lateral roots of Helianthus annuus

NASA Technical Reports Server (NTRS)

Moore, R.

1985-01-01

In order to determine if patterns of cell differentiation are similar in primary and lateral roots, I performed a morphometric analysis of the ultrastructure of calyptrogen, columella, and peripheral cells in primary and lateral roots of Helianthus annuus. Each cell type is characterized by a unique ultrastructure, and the ultrastructural changes characteristic of cellular differentiation in root caps are organelle specific. No major structural differences exist in the structures of the composite cell types, or in patterns of cell differentiation in caps of primary vs. lateral roots.

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

Basement membrane of mouse bone marrow sinusoids shows distinctive structure and proteoglycan composition: a high resolution ultrastructural study.

PubMed

Inoue, S; Osmond, D G

2001-11-01

Venous sinusoids in bone marrow are the site of a large-scale traffic of cells between the extravascular hemopoietic compartment and the blood stream. The wall of the sinusoids consists solely of a basement membrane interposed between a layer of endothelial cells and an incomplete covering of adventitial cells. To examine its possible structural specialization, the basement membrane of bone marrow sinusoids has now been examined by high resolution electron microscopy of perfusion-fixed mouse bone marrow. The basement membrane layer was discontinuous, consisting of irregular masses of amorphous material within a uniform 60-nm-wide space between apposing endothelial cells and adventitial cell processes. At maximal magnifications, the material was resolved as a random arrangement of components lacking the "cord network" formation seen in basement membranes elsewhere. Individual components exhibited distinctive ultrastructural features whose molecular identity has previously been established. By these morphological criteria, the basement membrane contained unusually abundant chondroitin sulfate proteoglycan (CSPG) revealed by 3-nm-wide "double tracks," and moderate amounts of both laminin as dense irregular coils and type IV collagen as 1-1.5-nm-wide filaments, together with less conspicuous amounts of amyloid P forming pentagonal frames. In contrast, 4.5-5-nm-wide "double tracks" characteristic of heparan sulfate proteoglycan (HSPG) were absent. The findings demonstrate that, in comparison with "typical" basement membranes in other tissues, the bone marrow sinusoidal basement membrane is uniquely specialized in several respects. Its discontinuous nature, lack of network organization, and absence of HSPG, a molecule that normally helps to maintain membrane integrity, may facilitate disassembly and reassembly of basement membrane material in concert with movements of adventitial cell processes as maturing hemopoietic cells pass through the sinusoidal wall: the exceptionally large quantity of CSPG may represent a reservoir of CD44 receptor for use in hemopoiesis. Copyright 2001 Wiley-Liss, Inc.

Psychological stress alters the ultrastructure and increases IL-1β and TNF-α in mandibular condylar cartilage

PubMed Central

Lv, Xin; Li, Qiang; Wu, Shun; Sun, Jing; Zhang, Min; Chen, Yong-Jin

2012-01-01

Psychological factors can be correlated with temporomandibular disorders (TMDs), but the mechanisms are unknown. In the present study, we examined the microstructural changes and expression of proinflammatory cytokines in mandibular condylar cartilage of the temporomandibular joint (TMJ) in a psychological stress animal model. Male Sprague-Dawley rats (8 weeks old, 210 ± 10 g) were randomly divided into 3 groups: psychological stress (PS, N = 48), foot shock (FS, N = 24), and control (N = 48). After inducing psychological stress using a communication box with the FS rats for 1, 3, or 5 weeks, PS rats were sacrificed and compared to their matched control littermates, which received no stress and were killed at the same times as the PS rats. Body and adrenal gland weight were measured and corticosterone and adrenocorticotropic hormone levels were determined by radioimmunoassay. After hematoxylin-eosin staining for histological observation, the ultrastructure of the TMJ was examined by scanning electron microscopy. Transcription and protein levels of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) were evaluated by ELISA and semi-quantitative RT-PCR. The PS group showed a significantly higher adrenal gland weight after 3 weeks of stress and higher hormone levels at weeks 1, 3, and 5. Histopathological changes and thinning cartilage were apparent at weeks 3 and 5. In the PS group, TNF-α increased at 1, 3, and 5 weeks and IL-1β increased significantly after 1 and 3 weeks of stress, and then decreased to normal levels by 5 weeks. Psychological stress increased plasma hormone levels and RT-PCR indicated increased IL-1β and TNF-α expression in the TMJ in a time-dependent manner. These results suggest that cytokine up-regulation was accompanied by stress-induced cartilage degeneration in the mandibular condyle. The proinflammatory cytokines play a potential role in initiating the cartilage destruction that eventually leads to the TMDs. PMID:22714807

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

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.

Ultrastructure and phylogeny of Ustilago coicis *

PubMed Central

Zhang, Jing-ze; Guan, Pei-gang; Tao, Gang; Ojaghian, Mohammad Reza; Hyde, Kevin David

2013-01-01

Ustilago coicis causes serious smut on Coix lacryma-jobi in Dayang Town, Jinyun County, Zhejiang Province of China. In this paper, ultrastructural assessments on fungus-host interactions and teliospore development are presented, and molecular phylogenetic analyses have been done to elucidate the phylogenetic placement of the taxon. Hyphal growth within infected tissues was both intracellular and intercellular and on the surface of fungus-host interaction, and the fungal cell wall and the invaginated host plasma membrane were separated by a sheath comprising two distinct layers between the fungal cell wall and the invaginated host plasma membrane. Ornamentation development of teliospore walls was unique as they appeared to be originated from the exosporium. In addition, internal transcribed spacer (ITS) and large subunit (LSU) sequence data showed that U. coicis is closely related to Ustilago trichophora which infects grass species of the genus Echinochloa (Poaceae). PMID:23549851

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

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

Centronuclear myopathy in a Border collie dog.

PubMed

Eminaga, S; Cherubini, G B; Shelton, G D

2012-10-01

A two-year old, male entire Border collie was presented with a one-year history of exercise-induced collapsing on the pelvic limbs. Physical examination revealed generalised muscle atrophy. Neurological examination supported a generalised neuromuscular disorder. Electromyography revealed spontaneous electrical activity in almost all muscles. Unfixed and formaldehyde-fixed biopsy samples were collected from the triceps brachii, longissimus and vastus lateralis muscles. Histopathological, histochemical and ultrastructural examinations of biopsy specimens were consistent with either centronuclear or myotubular myopathy. The dog clinically improved with supportive treatment with L-carnitine, co-enzyme Q10 and vitamin B compound. To the authors' knowledge, this is the first report of centronuclear/myotubular myopathy in a Border collie. © 2012 British Small Animal Veterinary Association.

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

A critical role for the transcription factor Scl in platelet production during stress thrombopoiesis.

PubMed

McCormack, Matthew P; Hall, Mark A; Schoenwaelder, Simone M; Zhao, Quan; Ellis, Sarah; Prentice, Julia A; Clarke, Ashleigh J; Slater, Nicholas J; Salmon, Jessica M; Jackson, Shaun P; Jane, Stephen M; Curtis, David J

2006-10-01

The generation of platelets from megakaryocytes in the steady state is regulated by a variety of cytokines and transcription factors, including thrombopoietin (TPO), GATA-1, and NF-E2. Less is known about platelet production in the setting of stress thrombopoiesis, a pivotal event in the context of cytotoxic chemotherapy. Here we show in mice that the transcription factor Scl is critical for platelet production after chemotherapy and in thrombopoiesis induced by administration of TPO. Megakaryocytes from these mice showed appropriate increases in number and ploidy but failed to shed platelets. Ultrastructural examination of Scl-null megakaryocytes revealed a disorganized demarcation membrane and reduction in platelet granules. Quantitative real-time polymerase chain reaction showed that Scl-null platelets lacked NF-E2, and chromatin immunoprecipitation analysis demonstrated Scl binding to the NF-E2 promoter in the human megakaryoblastic-cell line Meg-01, along with its binding partners E47, Lmo2, and the cofactors Ldb1 and GATA-2. These findings suggest that Scl acts up-stream of NF-E2 expression to control megakaryocyte development and platelet release in settings of thrombopoietic stress.

Effect of Diet on Adult House Fly (Diptera: Muscidae) Injected With the Salivary Gland Hypertrophy Virus (MdSGHV).

PubMed

Schaler, Jennifer; Stoffolano, John; Fausto, Anna Maria; Gambellini, Gabriella; Burand, John

2018-05-01

Research to date on the salivary gland hypertrophy virus (SGHV) in three species of flies has focused on adult flies having access to and taking a proteinaceous diet. Since many studies have shown that diet affects viral infection in numerous organisms, this study examined the effect of a protein-free diet on the effect of the SGHV virus in adult house flies, Musca domestica. L. Adults infected with the virus, and maintained on a sugar diet only, showed salivary glands with a blue rather than a grayish color and mild hypertrophy compared with protein-fed flies. It was possible to retrieve the virus from these glands and successfully infect noninfected flies. When injected at various ages, female flies fed only sugar showed that regardless of age, sugar-fed flies still became infected and showed the pathology of the glands. In addition, electron microscope studies revealed at the ultrastructural level that there was no difference between viral replication in cells from salivary glands of adults fed a proteinaceous-free diet and those feeding on protein.

Study of Histopathological and Molecular Changes of Rat Kidney under Simulated Weightlessness and Resistance Training Protective Effect

PubMed Central

Li, Zhili; Tian, Jijing; Abdelalim, Saed; Du, Fang; She, Ruiping; Wang, Desheng; Tan, Cheng; Wang, Huijuan; Chen, Wenjuan; Lv, Dongqiang; Chang, Lingling

2011-01-01

To explore the effects of long-term weightlessness on the renal tissue, we used the two months tail suspension model to simulate microgravity and investigated the simulated microgravity on the renal morphological damages and related molecular mechanisms. The microscopic examination of tissue structure and ultrastructure was carried out for histopathological changes of renal tissue morphology. The immunohistochemistry, real-time PCR and Western blot were performed to explore the molecular mechanisms associated the observations. Hematoxylin and eosin (HE) staining showed severe pathological kidney lesions including glomerular atrophy, degeneration and necrosis of renal tubular epithelial cells in two months tail-suspended rats. Ultrastructural studies of the renal tubular epithelial cells demonstrated that basal laminas of renal tubules were rough and incrassate with mitochondria swelling and vacuolation. Cell apoptosis in kidney monitored by the expression of Bax/Bcl-2 and caspase-3 accompanied these pathological damages caused by long-term microgravity. Analysis of the HSP70 protein expression illustrated that overexpression of HSP70 might play a crucial role in inducing those pathological damages. Glucose regulated protein 78 (GRP78), one of the endoplasmic reticulum (ER) chaperones, was up-regulated significantly in the kidney of tail suspension rat, which implied that ER-stress was associated with apoptosis. Furthermore, CHOP and caspase-12 pathways were activated in ER-stress induced apoptosis. Resistance training not only reduced kidney cell apoptosis and expression of HSP70 protein, it also can attenuate the kidney impairment imposed by weightlessness. The appropriate optimization might be needed for the long term application for space exploration. PMID:21625440

The effect of high-energy extracorporeal shock waves on hyaline cartilage of adult rats in vivo.

PubMed

Mayer-Wagner, Susanne; Ernst, Judith; Maier, Markus; Chiquet, Matthias; Joos, Helga; Müller, Peter E; Jansson, Volkmar; Sievers, Birte; Hausdorf, Jörg

2010-08-01

The aim of this study was to determine if extracorporeal shock wave therapy (ESWT) in vivo affects the structural integrity of articular cartilage. A single bout of ESWT (1500 shock waves of 0.5 mJ/mm(2)) was applied to femoral heads of 18 adult Sprague-Dawley rats. Two sham-treated animals served as controls. Cartilage of each femoral head was harvested at 1, 4, or 10 weeks after ESWT (n = 6 per treatment group) and scored on safranin-O-stained sections. Expression of tenascin-C and chitinase 3-like protein 1 (Chi3L1) was analyzed by immunohistochemistry. Quantitative real-time polymerase chain reaction (PCR) was used to examine collagen (II)alpha(1) (COL2A1) expression and chondrocyte morphology was investigated by transmission electron microscopy no changes in Mankin scores were observed after ESWT. Positive immunostaining for tenascin-C and Chi3L1 was found up to 10 weeks after ESWT in experimental but not in control cartilage. COL2A1 mRNA was increased in samples 1 and 4 weeks after ESWT. Alterations found on the ultrastructural level showed expansion of the rough-surfaced endoplasmatic reticulum, detachment of the cell membrane and necrotic chondrocytes. Extracorporeal shock waves caused alterations of hyaline cartilage on a molecular and ultrastructural level that were distinctly different from control. Similar changes were described before in the very early phase of osteoarthritis (OA). High-energy ESWT might therefore cause degenerative changes in hyaline cartilage as they are found in initial OA. Copyright 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Hazardous effects of fried potato chips on the development of retina in albino rats.

PubMed

El-Sayyad, Hassan I; Sakr, Saber A; Badawy, Gamal M; Afify, Hanaa S

2011-08-01

To evaluate the hazardous effects of fried potato chips upon the retina of two developmental stages of the albino rats aged 7 and 14 days from parturition. PREGNANT RATS WERE ARRANGED INTO TWO GROUPS: control pregnant rats and consequently their delivered newborns until reaching 7 and 14 days old from parturition and fried potato chips group in which pregnant rats at the 6th day of gestation maintained on diet formed of fried potato chips supplied from the market mixed with standard diet at a concentration of 50% per each till 7 and 14 post-partum. Three fold integrated approaches were adopted, namely, histological, ultrastructural and proteomic analysis. Histological examination of the retina of the experimental offsprings revealed many histopathological changes, including massive degeneration, vacuolization and cell loss in the ganglion cell layer, as well as general reduction in retinal size. At the ultrastructural level, the retina of experimental offsprings exhibited number of deformities, including ill differentiated and degenerated nuclear layer, malformed and vacuolated pigment epithelium with vesiculated and fragmented rough endoplasmic reticulum, degenerated outer segment of photoreceptors, as well as swollen choriocapillaris and loss of neuronal cells. Proteomic analysis of retina of the two experimental developmental stages showed variations in the expressed proteins as a result of intoxication which illustrated the adverse toxic effects of fried potato chips upon the retina. It can be concluded that the effect of fried potato chips on the development of retina in rats may be due to the presence of acrylamide or its metabolite.

Effects of 5-Fluorouracil on Morphology, Cell Cycle, Proliferation, Apoptosis, Autophagy and ROS Production in Endothelial Cells and Cardiomyocytes

PubMed Central

Focaccetti, Chiara; Bruno, Antonino; Magnani, Elena; Bartolini, Desirée; Principi, Elisa; Dallaglio, Katiuscia; Bucci, Eraldo O.; Finzi, Giovanna; Sessa, Fausto; Noonan, Douglas M.; Albini, Adriana

2015-01-01

Antimetabolites are a class of effective anticancer drugs interfering in essential biochemical processes. 5-Fluorouracil (5-FU) and its prodrug Capecitabine are widely used in the treatment of several solid tumors (gastro-intestinal, gynecological, head and neck, breast carcinomas). Therapy with fluoropyrimidines is associated with a wide range of adverse effects, including diarrhea, dehydration, abdominal pain, nausea, stomatitis, and hand-foot syndrome. Among the 5-FU side effects, increasing attention is given to cardiovascular toxicities induced at different levels and intensities. Since the mechanisms related to 5-FU-induced cardiotoxicity are still unclear, we examined the effects of 5-FU on primary cell cultures of human cardiomyocytes and endothelial cells, which represent two key components of the cardiovascular system. We analyzed at the cellular and molecular level 5-FU effects on cell proliferation, cell cycle, survival and induction of apoptosis, in an experimental cardioncology approach. We observed autophagic features at the ultrastructural and molecular levels, in particular in 5-FU exposed cardiomyocytes. Reactive oxygen species (ROS) elevation characterized the endothelial response. These responses were prevented by a ROS scavenger. We found induction of a senescent phenotype on both cell types treated with 5-FU. In vivo, in a xenograft model of colon cancer, we showed that 5-FU treatment induced ultrastructural changes in the endothelium of various organs. Taken together, our data suggest that 5-FU can affect, both at the cellular and molecular levels, two key cell types of the cardiovascular system, potentially explaining some manifestations of 5-FU-induced cardiovascular toxicity. PMID:25671635

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

PubMed

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

2017-09-01

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

Talin does not associate exclusively with alpha 2b beta 3 integrin in activated human platelets.

PubMed

Escolar, G; Diaz-Ricart, M; White, J G

1995-05-01

Talin is a high-molecular-weight protein that may stabilize connections between cytoplasmic actin and the submembrane portion of glycoprotein IIb-IIIa (GPIIb-IIIa) (alpha 2b beta 3 integrin) in thrombin-stimulated human platelets. Using morphologic and electrophoretic techniques, we have examined the association of talin with the cytoskeleton of platelets activated by thrombin in the presence of fibrinogen-coated gold particles (Fgn/Au). Ultrastructural studies confirmed the presence of Fgn/Au firmly bound to the outside membranes of detergent-extracted platelets. Immunoblots of protein bands showed GPIIIa, but not talin, associated with cytoskeletons of activated platelets. Immunogold cytochemical techniques were performed on ultrathin cryosections of whole platelets to localize talin at the ultrastructural level. Studies were performed on normal platelets and platelets defective in GPIIb-IIIa (Glanzmann's thrombasthenia) and GPIb (Bernard-Soulier syndrome). Talin was randomly distributed in the cytoplasm of resting platelets. Activation resulted in binding of Fgn/Au to the surface membrane and redistribution of talin to the submembrane region. However, no definitive colocalization between the two markers was noted. Activated thrombasthenic platelets failed to bind Fgn/Au, but talin was localized to the submembrane location. After activation, talin was confined to the submembrane zone of Bernard-Soulier syndrome platelets. No definitive colocalization was observed between large clusters of Fgn/Au-occupied receptors and talin distributed in the submembrane region. GPIb and GPIIb-IIIa are not necessary for talin to localize in the submembrane region of activated cells. Talin does not redistribute exclusively with GPIIb-IIIa, and it may stabilize connections with other glycoproteins.

Effect of allantoin on experimentally induced gastric ulcers: Pathways of gastroprotection.

PubMed

da Silva, Dayane Moreira; Martins, José Luís Rodrigues; de Oliveira, Danillo Ramos; Florentino, Iziara Ferreira; da Silva, Daiany Priscilla Bueno; Dos Santos, Fernanda Cristina Alcântara; Costa, Elson Alves

2018-02-15

Gastric ulcer affects people worldwide, and its inefficacy and recurrence have fueled the search for new therapeutic strategies. Despite the well-known use of allantoin in medicines and cosmetic products, its effect has not yet been studied with regard to gastric ulcer. Hence, the aim of the present study was to explore the pharmaco-mechanistic efficacy of allantoin against commonly harmful agents that cause injuries to the stomach. Ethanol, indomethacin, and stress-induced gastric ulcer models were adopted, in addition to pylorus ligature, a quantification of vascular permeability, glutathione (GSH), gastric adhered mucus, prostaglandin (PGE 2 ), pro-inflammatory cytokines levels, myeloperoxidase (MPO), and catalase (CAT) activities. The gastric lesions were examined by gross, histological, and ultrastructural features. The results showed that treatment with allantoin (60mg/kg, per oral) reduced the gastric ulcer formation in all models. Furthermore, allantoin reduced the parameters of gastric acid secretion and attenuated both the vascular permeability and MPO activity. The levels of pro-inflammatory cytokines were also reduced, accompanied by a restoration of CAT activity and GSH levels. Notably, allantoin treatment preserved the gastric-adhered mucus and PGE 2 levels after ethanol administration. Microscopic and ultrastructural analysis revealed that allantoin maintained tissue integrity and prevented morphological changes in cells caused by ethanol. In summary, we demonstrated for the first time that allantoin possesses gastroprotective activity through anti-inflammatory, anti-oxidative, antisecretory, and cytoprotective mechanisms. The antisecretory and cytoprotective mechanisms are probably associated with an increase in PGE 2 levels. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of management in gestational diabetes mellitus with normal prepregnancy body mass index on pregnancy outcomes and placental ultrastructures: a prospective cohort study.

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.

Centripetal myosin redistribution in thrombin-stimulated platelets. Relationship to platelet Factor 4 secretion.

PubMed

Painter, R G; Ginsberg, M H

1984-11-01

We have examined the F-actin and myosin distribution in resting and thrombin-activated platelets by double label immunofluorescence microscopy. In resting, discoid platelets, F-actin and myosin staining was distributed in a diffuse pattern throughout the interior of the cell with slight accentuation at the cell periphery. In contrast, platelet factor 4 antigen (PF4) was more centrally localized in a fine punctate distribution which is consistent with its localization in alpha-granules. Within 5 sec after thrombin stimulation both F-actin and myosin staining were increased at the periphery of the now spherical platelets. Subsequently, a myosin-containing spherical structure decreased in diameter closely surrounding a phase-dense central zone. In contrast, F-actin staining continued to be accentuated at the cell periphery and was prominent in filopodia and blebs. As previously shown, PF4 staining was localized after 30 sec within large intracellular masses that corresponded to closed vacuolar structures at the ultrastructural level. Morphometric analysis of electron micrographs showed that formation of these vacuolar structures kinetically paralleled alpha-granule disappearance and preceded PF4 release. These PF4-containing structures translocated to the cell periphery after 1-3 min, where they appeared to fuse with the plasma membrane. Ultrastructural analysis of thin sections showed that the myosin-rich spherical structure spatially and temporally correlated with a band of microfilaments that closely surrounded the organelle-rich central zone of the cell. Morphometric analysis of these micrographs showed that the absolute volume of this central zone decreased with time after thrombin addition, showing a significant change after 15 sec and reaching a maximum value after 3-5 min. Changes in the volume of this compartment kinetically preceded PF4 release. On the basis of these data, we propose that an actomyosin contractile force is generated which centripetally redistributes the myosinrich structure and organelle zone. Conceivably this inward force may not only accelerate granule-granule fusion to form intracellular secretory vacuoles, but may also provide aid in their extrusion toward the platelet plasma membrane.

Micromorphology of sialoliths in submandibular salivary gland: a scanning electron microscope and X-ray diffraction analysis.

PubMed

Kasaboğlu, Oğuzcan; Er, Nuray; Tümer, Celal; Akkocaoğlu, Murat

2004-10-01

Sialoliths are common in the submandibular gland and its duct system. The exact cause of formation of a sialolith is still a matter of debate. The aim of this study was to analyze 6 sialoliths ultrastructurally to determine their development mechanism in the submandibular salivary glands. Six sialoliths retrieved from the hilus and duct of the submandibular salivary glands of 6 patients with sialadenitis were analyzed ultrastructurally by scanning electron microscope and x-ray diffractometer. Scanning electron microscope revealed mainly irregular, partly rudely hexagonal, needle-like and plate-shaped crystals. The cross-section from the surface to the inner part of the sialoliths showed no organic material. X-ray diffraction showed that the sialoliths were composed of hydroxyapatite crystals. Energy dispersive x-ray microanalysis showed that all of the samples contained high levels of Ca and P, and small amounts of Mg, Na, Cl, Si, Fe, and K. The main structures of the submandibular sialoliths were found to be hydroxyapatite crystals. No organic cores were observed in the central parts of the sialoliths. In accordance with these preliminary results, sialoliths in the submandibular salivary glands may arise secondary to sialadenitis, but not via a luminal organic nidus.

An immunohistochemical and ultrastructural study of the pericellular matrix of uneroded hypertrophic chondrocytes in the mandibular condyle of aged c-src-deficient mice.

PubMed

Shibata, Shunichi; Baba, Otto; Oda, Tsuyoshi; Yokohama-Tamaki, Tamaki; Qin, Chunlin; Butler, William T; Sakakura, Yasunori; Takano, Yoshiro

2008-03-01

Previous studies indicate that hypertrophic chondrocytes can transdifferentiate or dedifferentiate and redifferentiate into bone cells during the endochondral bone formation. Mandibular condyle in aged c-src-deficient mice has incremental line-like striations consisting of cartilaginous and non-cartilaginous layers, and the former contains intact hypertrophic chondrocytes in uneroded lacunae. The purpose of this study is to determine the phenotype changes of uneroded hypertrophic chondrocytes. Immunohistochemical and ultrastructural examinations of the pericellular matrix of hypertrophic chondrocytes in the upper, middle, and lower regions of the mandibular condyle were conducted in aged c-src-deficient mice, using several antibodies of cartilage/bone marker proteins. Co-localisation of aggrecan, type I collagen, and dentin matrix protein-1 (DMP-1) or matrix extracellular phosphoprotein (MEPE) was detected in the pericellular matrix of the middle region. Ultrastructurally, granular substances in the pericellular matrix of the middle region were the remains of upper region chondrocytes, which were mixed with thick collagen fibrils. In the lower region, the width of the pericellular matrix and the amount of collagen fibrils were increased. Versican, type I collagen, DMP-1, and MEPE were detected in the osteocyte lacunae. Additionally, DMP-1 and MEPE were detected in the pericellular matrix of uneroded hypertrophic chondrocytes located in the lower, peripheral region of the mandibular condyle in younger c-src-deficient mice, but not in the aged wild-type mice. These results indicate that long-term survived, uneroded hypertrophic chondrocytes, at least in a part, acquire osteocytic characteristics.

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

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.

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

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.

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.

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.

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.

Ultrastructural characterization of primary cilia in pathologically characterized human glioblastoma multiforme (GBM) tumors.

PubMed

Moser, Joanna J; Fritzler, Marvin J; Rattner, Jerome B

2014-01-01

Primary cilia are non-motile sensory cytoplasmic organelles that are involved in cell cycle progression. Ultrastructurally, the primary cilium region is complex, with normal ciliogenesis progressing through five distinct morphological stages in human astrocytes. Defects in early stages of ciliogenesis are key features of astrocytoma/glioblastoma cell lines and provided the impetus for the current study which describes the morphology of primary cilia in molecularly characterized human glioblastoma multiforme (GBM) tumors. Seven surgically resected human GBM tissue samples were molecularly characterized according to IDH1/2 mutation status, EGFR amplification status and MGMT promoter methylation status and were examined for primary cilia expression and structure using indirect immunofluorescence and electron microscopy. We report for the first time that primary cilia are disrupted in the early stages of ciliogenesis in human GBM tumors. We confirm that immature primary cilia and basal bodies/centrioles have aberrant ciliogenesis characteristics including absent paired vesicles, misshaped/swollen vesicular hats, abnormal configuration of distal appendages, and discontinuity of centriole microtubular blades. Additionally, the transition zone plate is able to form in the absence of paired vesicles on the distal end of the basal body and when a cilium progresses beyond the early stages of ciliogenesis, it has electron dense material clumped along the transition zone and a darkening of the microtubules at the proximal end of the cilium. Primary cilia play a role in a variety of human cancers. Previously primary cilia structure was perturbed in cultured cell lines derived from astrocytomas/glioblastomas; however there was always some question as to whether these findings were a cell culture phenomena. In this study we confirm that disruptions in ciliogenesis at early stages do occur in GBM tumors and that these ultrastructural findings bear resemblance to those previously observed in cell cultures. This is the first study to demonstrate that defects in cilia expression and function are a true hallmark of GBM tumors and correlate with their unrestrained growth. A review of the current ultrastructural profiles in the literature provides suggestions as to the best possible candidate protein that underlies defects in the early stages of ciliogenesis within GBM tumors.

Simulation of Blast Loading on an Ultrastructurally-based Computational Model of the Ocular Lens

DTIC Science & Technology

2013-10-01

gradient components in the axial ( F22 ) and radial (F11) directions. One can observe the very large deformation (approaching 800%) and 5 Figure 5...and (bottom left) show deformation gradient in axial ( F22 ) and radial (F11) directions. (bottom right) normalized force versus displacement curve for

The effect of urothelial damage on ureteric motility. An ultrastructural and functional study.

PubMed

Ugaily-Thulesius, L; Thulesius, O; Sabha, M

1988-07-01

Evidence of a leaky urothelial barrier in bilharzial uropathy is presented. The ultrastructural basis of this concept is demonstrated together with its functional consequences. The study was conducted on 4 ureters obtained at surgery from patients with non-functioning kidneys due to chronic bilharzial infections. Six normal ureters from kidney donors served as controls. Light and electron microscopic studies showed a reduced thickness of the transitional epithelium together with localised disruption of intercellular junctions and infiltration of red blood cells. The functional studies involved in vitro demonstration of stable phasic peristaltic contractions which were fundamentally altered by the addition of urine. The changes in motility included increase in contractile frequency and elevation of basal tone, inducing a state of hypermotility which could be equated with ureteric spasm. These changes were partly reversible upon administration of the histamine l-blocker, mepyramine. Evidence is presented to show that these changes might be induced in vivo by histamine released from mast cells triggered by urine leaking through a damaged urothelial barrier. The functional consequences (pain, spasm) are discussed.

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

NASA Technical Reports Server (NTRS)

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

1975-01-01

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

Genotype-dependent efficiency of endosperm development in culture of selected cereals: histological and ultrastructural studies.

PubMed

Popielarska-Konieczna, Marzena; Kozieradzka-Kiszkurno, Małgorzata; Tuleja, Monika; Ślesak, Halina; Kapusta, Paweł; Marcińska, Izabela; Bohdanowicz, Jerzy

2013-02-01

The paper reports studies, including histological and ultrastructural analyses, of in vitro cell proliferation and development of immature endosperm tissue isolated from caryopses of Triticum aestivum, Triticum durum, and Triticosecale plants. Endosperm isolated at 7-10 days post-anthesis developed well on MS medium supplemented with auxins and/or cytokinins. The efficiency of endosperm response was highly genotype-dependent and best in two winter cultivars of hexaploid species. The pathways of development and proliferation were very similar among the selected species and cultivars. Histological and scanning electron microscope (SEM) analysis revealed that only the part of the endosperm not touching the medium surface continued growth and development, resulting in swelling. The central part of swollen regions was composed mainly of cells containing many large starch grains. The peripheric parts of developed endosperm consisted of highly vacuolated cells and small cells with dense cytoplasm. SEM showed that cells from the swollen region were covered partially with a membraneous structure. Transmission electron microscope studies of cells from the outer part of the developing region showed features typical for cell activity connected with lipid metabolism.

Changes in lung ultrastructure following heterologous and homologous serum albumin infusion in the treatment of hemorrhagic shock.

PubMed Central

Moss, G S; Das Gupta, T K; Brinkman, R; Sehgal, L; Newsom, B

1979-01-01

The object of this study was to compare the ultrastructure pulmonary effects of the infusion of homologous and heterologous serum albumin solution in the treatment of hemorrhagic shock in baboons. Adult baboons subjected to hemorrhagic shock were resuscitated with either baboon serum albumin, human serum albumin, or Ringer's lactate solution. The lungs were fixed in vivo with potassium pyroantimony, a solution which produces electron dense interstitial precipitation of sodium. The lungs from animals resuscitated with baboon serum albumin showed evidence of interstitial edema, including dispersion of collagen fibers, interstitial smudging and increased interstital sodium concentrations. Similar changes were seen following human serum albumin infusions. Lung tissue from animals treated with Ringer's lactate solution showed minimal changes from normal. These results suggest that interstitial pulmonary edema develops after either homologous or heterologous serum albumin infusion in the treatment of hemorrhagic shock in baboons. Images Figs. 2a and b. Figs. 3a and b. Figs. 4a and b. Figs. 5a and b. Figs. 6a and b. PMID:106780

High humidity hot air impingement blanching (HHAIB) enhances drying rate and softens texture of apricot via cell wall pectin polysaccharides degradation and ultrastructure modification.

PubMed

Deng, Li-Zhen; Mujumdar, A S; Yang, Xu-Hai; Wang, Jun; Zhang, Qian; Zheng, Zhi-An; Gao, Zhen-Jiang; Xiao, Hong-Wei

2018-09-30

The effects of high humidity hot air impingement blanching (HHAIB) over a range of application times (30, 60, 90, and 120 s) on drying characteristics, hardness, cell wall pectin fractions contents and nanostructure, as well ultrastructure of apricot were investigated. Results showed that HHAIB reduced drying time and decreased the hardness of apricot by 20.7%-34.5% and 46.57%-71.89%, respectively. The water-soluble pectin (WSP) contents increased after blanching, while the contents of chelate-soluble pectin (CSP) and sodium-carbonate-soluble pectin (NSP) decreased significantly (P < 0.05). The hardness and drying time were found to correlate inversely with the WSP content, but positively with CSP and NSP contents. Atomic force microscopy (AFM) detection showed the decomposition and degradation of pectin fractions during blanching. Additionally, transmission electron microscopy (TEM) observation indicated that the cell wall structure was degraded and middle lamella integrity was destroyed by blanching. Copyright © 2018 Elsevier Ltd. All rights reserved.

Calreticulin--an endoplasmic reticulum protein with calcium-binding activity is also found in the extracellular matrix.

PubMed

Somogyi, Eszter; Petersson, Ulrika; Hultenby, Kjell; Wendel, Mikael

2003-04-01

Previous studies have reported that calreticulin (CRT), a calcium-binding and chaperoning protein, is expressed only in the endoplasmatic reticulum, nucleus and at the cell surface. In this study we clearly show that odontoblasts and predentin matrix contain CRT. To our knowledge, this is the first time CRT has been described in the extracellular matrix. The expression of CRT was studied by immunohistochemistry, ultrastructural immunocytochemistry and in situ hybridization in developing rat teeth. CRT was detected as a 59-kDa protein in rat pulp cell culture medium and dentin extracellular matrix extract by Western blotting. The presence of the protein was shown in rat odontoblasts and predentin with immunohistochemistry. At the ultrastructural level, the labeling was distributed in the rat odontoblasts, ameloblasts and predentin. Northern blotting showed the presence of CRT mRNA in rat molars, which was confirmed by in situ hybridization in odontoblasts and ameloblasts. We now present the first convincing evidence that CRT is found in extracellular matrix where it may play an important role in mineralization.

Incomplete gastric metaplasia in children with insulin-dependent diabetes mellitus and celiac disease. An ultrastructural study

PubMed Central

Bertini, Marina; Sbarbati, Andrea; Valletta, Enrico; Pinelli, Leonardo; Tatò, Luciano

2001-01-01

Background The association of insulin-dependent diabetes mellitus (IDDM) and celiac disease (CD) has been widely reported in children but the relationship between the two conditions is incompletely understood. Moreover, specific studies on intestinal biopsies of patients with the association of the two diseases are still lacking. Methods We studied the ultrastructure of the duodenal mucosa in 12 patients with both IDDM and CD. Results All patients had either total or partial atrophy of duodenal mucosa. In seven subjects, an accumulation of electrondense granules in the apical cytoplasm of groups of enterocytes was found. In four of them, a double population of granules existed (mean diameter: 400-800 nm and 100-200 nm respectively) showing a biphasic pattern. In the other three patients, only smaller granules (100- 200 nm) were found in the enterocytes. Conclusions The present work suggests that patients with IDDM/CD may represent a subgroup in the context of the CD population. Intestinal biopsies of such individuals often show accumulation of electrondense granules in the apical cytoplasm of enterocytes that can be interpreted as incomplete gastric metaplasia. PMID:11466133

Labyrinths, columns and cavities: new internal features of pollen grain walls in the Acanthaceae detected by FIB-SEM.

PubMed

House, Alisoun; Balkwill, Kevin

2016-03-01

External pollen grain morphology has been widely used in the taxonomy and systematics of flowering plants, especially the Acanthaceae which are noted for pollen diversity. However internal pollen wall features have received far less attention due to the difficulty of examining the wall structure. Advancing technology in the field of microscopy has made it possible, with the use of a focused ion beam-scanning electron microscope (FIB-SEM), to view the structure of pollen grain walls in far greater detail and in three dimensions. In this study the wall structures of 13 species from the Acanthaceae were investigated for features of potential systematic relevance. FIB-SEM was applied to obtain precise cross sections of pollen grains at selected positions for examining the wall ultrastructure. Exploratory studies of the exine have thus far identified five basic structural types. The investigations also show that similar external pollen wall features may have a distinctly different internal structure. FIB-SEM studies have revealed diverse internal pollen wall features which may now be investigated for their systematic and functional significance.

Previously unknown apicomplexan species infecting Iceland scallop, Chlamys islandica (Müller, 1776), queen scallop, Aequipecten opercularis L., and king scallop, Pecten maximus L.

PubMed

Kristmundsson, Árni; Helgason, Sigurður; Bambir, Slavko Helgi; Eydal, Matthías; Freeman, Mark A

2011-11-01

Examination of three scallop species from three separate locations: Iceland scallop from Icelandic waters, king scallop from Scottish waters and queen scallop from Faroese and Scottish waters, revealed infections of a previously unknown apicomplexan parasite in all three scallop species. Developmental forms observed in the shells appeared to include both sexual and asexual stages of the parasite, i.e. merogony, gametogony and sporogony, which suggests a monoxenous life cycle. Meronts, gamonts, zygotes and mature oocysts were solely found in the muscular tissue. Zoites, which could be sporozoites and/or merozoites, were observed in great numbers, most frequently in muscles, both intracellular and free in the extracellular space. Zoites were also common inside haemocytes. Examination of the ultrastructure showed that the zoites contained all the major structures characterizing apicomplexans. This apicomplexan parasite is morphologically different from other apicomplexan species previously described from bivalves. Presently, its systematic position within the phylum Apicomplexa cannot be ascertained. Copyright © 2011 Elsevier Inc. All rights reserved.

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.

Ultrastructural and developmental evidence of phytotoxicity on cos lettuce (Lactuca sativa) associated with nonylphenol exposure.

PubMed

de Bruin, Willeke; van der Merwe, Chris; Kritzinger, Quenton; Bornman, Riana; Korsten, Lise

2017-02-01

It has long been understood that the presence of endocrine disrupter chemicals (EDCs) in water can affect the reproductive, behavioural and regulatory systems of different types of mammals. Thus far, only a handful of studies have examined its impact on plant systems. Present research is limited to the potential uptake of these chemicals by plants and the general phytotoxic effects it can elicit. The aim of this study was to determine what effect an EDC has on developing plant and cell organelles and how it affects it. In this study, cos lettuce plants were exposed to different concentrations of nonylphenol (NP), an EDC, in a static hydroponic system. Changes in plant morphology, mass and length, chlorophyll content, as well as electrolyte leakage were examined. Furthermore an in-depth investigation of the plant cell ultrastructure was carried out with transmission electron microscopy. Results indicated that cos lettuce growth was severely restricted, chlorophyll content was reduced, leakage of electrolytes increased and roots were stunted especially after ≥3200 μg/l NP exposures. The structure of the rough endoplasmic reticulum, vacuole and chloroplast were also changed. This study emphasizes the importance of water quality management, since the presence of an EDC, like NP, can negatively impact the yield and internal structure of one of the world's most significant salad crops, namely lettuce. Copyright © 2016 Elsevier Ltd. All rights reserved.

In vivo evaluation of the efficacy of albendazole sulfoxide and albendazole sulfoxide loaded solid lipid nanoparticles against hydatid cyst.

PubMed

Ahmadnia, Sara; Moazeni, Mohammad; Mohammadi-Samani, Soliman; Oryan, Ahmad

2013-10-01

Cystic echinococcosis (CE) is caused by the larval stage of Echinococcus granulosus, which in this disease the metacestode develop in visceral organs especially liver and lungs. The disease is present worldwide and affects humans as well as herbivores including cattle, sheep, camels, horses and others. Benzimidazole carbamate derivatives, such as mebendazole and albendazole, are currently used for chemotherapeutic treatment of CE in inoperable patients and have to be applied in high doses for extended periods of time, and therefore adverse side effects are frequently observed. This study was designed to evaluate and compare the in vivo effects of 0.5 mg/kg, BID, albendazole sulfoxide (ricobendazole) and two different therapeutic regimens of 0.5 mg/kg BID and 2 mg/kg every 48 h of albendazole sulfoxide loaded solid lipid nanoparticles. Albendazole sulfoxide loaded solid lipid nanoparticles was prepared by solvent diffusion-evaporation method. Fifty Balb/c mice were infected by intraperitoneal injection of protoscoleces and 8 months post infection, the infected mice were treated for 15 days with the above mentioned regimens. They were then euthanized and the size and weight of the cysts as well as their ultrastructural changes were investigated. Although the cysts showed reduced size and weight in the treated animals but these reductions were not statistically significant. The cysts in the animals which received albendazole sulfoxide loaded SLN every 48 h showed more ultrastructural modification. However, these ultrastructural changes should be supported by further biochemical and molecular studies before introducing it as an efficient therapeutic regimen for treatment of human and animal hydatid disease. Copyright © 2013 Elsevier Inc. All rights reserved.

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.

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

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

Thuy, Nguyen Thanh, E-mail: ngtthuy02@yahoo.com; Huy, Tran Quang, E-mail: huytq@nihe.org.vn; Nga, Phan Thi

We describe the ultrastructure of the NamDinh virus (NDiV), a new member of the order Nidovirales grown in the C6/36 mosquito cell line. Uninfected and NDiV-infected cells were investigated by electron microscopy 24–48 h after infection. The results show that the viral nucleocapsid-like particles form clusters concentrated in the vacuoles, the endoplasmic reticulum, and are scattered in the cytoplasm. Mature virions of NDiV were released as budding particles on the cell surface where viral components appear to lie beneath and along the plasma membrane. Free homogeneous virus particles were obtained by ultracentrifugation on sucrose gradients of culture fluids. The sizemore » of the round-shaped particles with a complete internal structure was 80 nm in diameter. This is the first study to provide information on the morphogenesis and ultrastructure of the first insect nidovirus NDiV, a missing evolutionary link in the emergence of the viruses with the largest RNA genomes. - Highlights: • NamDinh virus (NDiV), a new member of the order Nidovirales was tested in cultured cell line. • The morphogenesis and ultrastructure of NDiV were investigated by electron microscopy. • The viral nucleocapsid-like particles clustered and scattered in the cytoplasm. • NDiVs were released as budding particles on the cell surface. • The size of the viral particles with a complete internal structure was 80 nm in diameter.« less

Bioabsorption of cadmium, copper and lead by the red macroalga Gelidium floridanum: physiological responses and ultrastructure features.

PubMed

dos Santos, Rodrigo W; Schmidt, Éder C; de L Felix, Marthiellen R; Polo, Luz K; Kreusch, Marianne; Pereira, Debora T; Costa, Giulia B; Simioni, Carmen; Chow, Fungyi; Ramlov, Fernanda; Maraschin, Marcelo; Bouzon, Zenilda L

2014-07-01

Heavy metals, such as lead, copper, cadmium, zinc, and nickel, are among the most common pollutants found in both industrial and urban effluents. High concentrations of these metals cause severe toxic effects, especially to organisms living in the aquatic ecosystem. Cadmium (Cd), lead (Pb) and copper (Cu) are the heavy metals most frequently implicated as environmental contaminants, and they have been shown to affect development, growth, photosynthesis and respiration, and morphological cell organization in seaweeds. This paper aimed to evaluate the effects of 50μM and 100μM of Cd, Pb and Cu on growth rates, photosynthetic pigments, biochemical parameters and ultrastructure in Gelidium floridanum. To accomplish this, apical segments of G. floridanum were individually exposed to the respective heavy metals over a period of 7 days. Plants exposed to Cd, Cu and Pb showed discoloration of thallus pigmentation, chloroplast alteration, especially degeneration of thylakoids, and decrease in photosynthetic pigments, such as chlorophyll a and phycobiliproteins, in samples treated with Cd and Cu. Moreover, cell wall thickness and the volume of plastoglobuli increased. X-ray microanalysis detected Cd, Cu and Pb absorption in the cell wall. The results indicate that Cd, Pb and Cu negatively affect metabolic performance and cell ultrastructure in G. floridanum and that Cu was more toxic than either Pb or Cd. Copyright © 2014 Elsevier Inc. All rights reserved.

Flavocoxid, a Natural Antioxidant, Protects Mouse Kidney from Cadmium-Induced Toxicity

PubMed Central

Trichilo, Vincenzo; Pisani, Antonina; Malta, Consuelo; Laurà, Rosalba; Santoro, Domenico; Germanà, Antonino; Minutoli, Letteria

2018-01-01

Background Cadmium (Cd), a diffused environmental pollutant, has adverse effects on urinary apparatus. The role of flavocoxid, a natural flavonoid with antioxidant activity, on the morphological and biochemical changes induced in vivo by Cd in mice kidney was evaluated. Methods C57 BL/6J mice received 0.9% NaCl alone, flavocoxid (20 mg/kg/day i.p.) alone, Cd chloride (CdCl2) (2 mg/kg/day i.p.) alone, or CdCl2 plus flavocoxid (2 mg/kg/day i.p. plus 20 mg/kg/day i.p.) for 14 days. The kidneys were processed for biochemical, structural, ultrastructural, and morphometric evaluation. Results Cd treatment alone significantly increased urea nitrogen and creatinine, iNOS, MMP-9, and pERK 1/2 expression and protein carbonyl; reduced GSH, GR, and GPx; and induced structural and ultrastructural changes in the glomeruli and in the tubular epithelium. After 14 days of treatment, flavocoxid administration reduced urea nitrogen and creatinine, iNOS, MMP-9, and pERK 1/2 expression and protein carbonyl; increased GSH, GR, and GPx; and showed an evident preservation of the glomerular and tubular structure and ultrastructure. Conclusions A protective role of flavocoxid against Cd-induced oxidative damages in mouse kidney was demonstrated for the first time. Flavocoxid may have a promising antioxidant role against environmental Cd harmful effects on glomerular and tubular lesions. PMID:29849925

Flavocoxid, a Natural Antioxidant, Protects Mouse Kidney from Cadmium-Induced Toxicity.

PubMed

Micali, Antonio; Pallio, Giovanni; Irrera, Natasha; Marini, Herbert; Trichilo, Vincenzo; Puzzolo, Domenico; Pisani, Antonina; Malta, Consuelo; Santoro, Giuseppe; Laurà, Rosalba; Santoro, Domenico; Squadrito, Francesco; Altavilla, Domenica; Germanà, Antonino; Minutoli, Letteria

2018-01-01

Cadmium (Cd), a diffused environmental pollutant, has adverse effects on urinary apparatus. The role of flavocoxid, a natural flavonoid with antioxidant activity, on the morphological and biochemical changes induced in vivo by Cd in mice kidney was evaluated. C57 BL/6J mice received 0.9% NaCl alone, flavocoxid (20 mg/kg/day i.p.) alone, Cd chloride (CdCl 2 ) (2 mg/kg/day i.p.) alone, or CdCl 2 plus flavocoxid (2 mg/kg/day i.p. plus 20 mg/kg/day i.p.) for 14 days. The kidneys were processed for biochemical, structural, ultrastructural, and morphometric evaluation. Cd treatment alone significantly increased urea nitrogen and creatinine, iNOS, MMP-9, and pERK 1/2 expression and protein carbonyl; reduced GSH, GR, and GPx; and induced structural and ultrastructural changes in the glomeruli and in the tubular epithelium. After 14 days of treatment, flavocoxid administration reduced urea nitrogen and creatinine, iNOS, MMP-9, and pERK 1/2 expression and protein carbonyl; increased GSH, GR, and GPx; and showed an evident preservation of the glomerular and tubular structure and ultrastructure. A protective role of flavocoxid against Cd-induced oxidative damages in mouse kidney was demonstrated for the first time. Flavocoxid may have a promising antioxidant role against environmental Cd harmful effects on glomerular and tubular lesions.

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.

The impact of black seed oil on tramadol-induced hepatotoxicity: Immunohistochemical and ultrastructural study.

PubMed

Omar, Nesreen Moustafa; Mohammed, Mohammed Amin

2017-06-01

The natural herb, black seed (Nigella Sativa; NS) is one of the most important elements of folk medicine. The aim was to evaluate the impact of Nigella Sativa Oil (NSO) on the changes induced by tramadol in rat liver. Twenty four albino rats were used. given intraperitoneal and oral saline for 30days. TR-group: given intraperitoneal tramadol (20, 40, 80mg/kg/day) in the first, middle and last 10days of the experiment, respectively. TR+NS group: administered intraperitoneal tramadol in similar doses to TR-group plus oral NSO (4ml/kg/day) for 30days. Immunohistochemical, electron microscopic, biochemical and statistical studies were performed. TR-group displayed disarranged hepatic architecture, hepatic congestion, hemorrhage and necrosis. Apoptotic hepatocytes, mononuclear cellular infiltration and a significant increase in the number of anti-CD68 positive cells were observed. Ultrastructurally, hepatocytes showed shrunken nuclei, swollen mitochondria, many lysosomes and autophagic vacuoles. Activated Ito and Von Kupffer cells were also demonstrated. Elevated serum levels of AST, ALT, ALP and bilirubin were noticed. NSO administration resulted in preservation of hepatic histoarchitecture and ultrastructure and significant reductions in the number of anti-CD68 positive cells and serum levels of liver seromarkers. In conclusion, NSO administration could mitigate the alterations induced by tramadol in rat liver. Copyright © 2017 Elsevier GmbH. All rights reserved.

Ultrastructural identification of noradrenergic nerve terminals and vasopressin-containing neurons of the paraventricular nucleus in the same thin section.

PubMed

Silverman, A J; Hou-Yu, A; Oldfield, B J

1983-09-01

Since many peptidergic cell groups receive a diverse and complex monoaminergic innervation, we have developed a double-label procedure to visualize a peptide and a catecholamine in the same ultrathin section. Radiolabeled norepinephrine (NE) is applied locally and its reuptake into NE terminals is demonstrated by ultrastructural radioautography. Controls in this and other studies demonstrate that the NE labels only NE (and possibly epinephrine) terminals and not dopaminergic or serotonergic terminals. In the same tissue, vasopressin is localized by immunocytochemistry on unembedded sections that are subsequently embedded in epoxy resins for thin sectioning. The procedure as described here shows that NE terminals in the periventricular zone of the paraventricular nucleus of the hypothalamus innervate both vasopressin-positive and vasopressin-negative structures. This technique is useful in determining the chemical connectivity of the hypothalamus.

Cytogenetical and ultrastructural effects of copper on root meristem cells of Allium sativum L.

PubMed

Liu, Donghua; Jiang, Wusheng; Meng, Qingmin; Zou, Jin; Gu, Jiegang; Zeng, Muai

2009-04-01

Different copper concentrations, as well as different exposure times, were applied to investigate both cytogenetical and ultrastructural alterations in garlic (Allium sativum L.) meristem cells. Results showed that the mitotic index decreased progressively when either copper concentration or exposure time increased. C-mitosis, anaphase bridges, chromosome stickiness and broken nuclei were observed in the copper treated root tip cells. Some particulates containing the argyrophilic NOR-associated proteins were distributed in the nucleus of the root-tip cells and the amount of this particulate material progressively increased with increasing exposure time. Finally, the nucleolar material was extruded from the nucleus into the cytoplasm. Also, increased dictyosome vesicles in number, formation of cytoplasmic vesicles containing electron dense granules, altered mitochondrial shape, disruption of nuclear membranes, condensation of chromatin material, disintegration of organelles were observed. The mechanisms of detoxification and tolerance of copper are briefly discussed.

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.

Development of the larval nervous system of the sand dollar, Dendraster excentricus.

PubMed

Burke, R D

1983-01-01

Transformation of the gastrula to the pluteus includes development of the ability of the larva to control the direction of ciliary beat and coordinate activities of the ciliary band with activities of the esophageal muscles (48-60 h, 15 degrees C). Glyoxylic acid-induced fluorescence shows several cells of the animal plate to contain catecholamines in the 36-h gastrula. As the ectoderm thickens to form the ciliary band (36 48 h), the catecholamine-containing cells increase in number and occur dispersed throughout the band. Tissues with the ultrastructural characteristics of nerves first became apparent associated with the ciliary band in 60-h larvae. The coincident development of coordinated behaviour and the appearance of cells with ultrastructural and histochemical characteristics of nerves suggests that the larval nervous system is derived at least in part from cells of the animal plate and develops in association with the ciliary bands.

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.

Axoglial contacts in the area postrema of the cat - An ultrastructural study

NASA Technical Reports Server (NTRS)

Damelio, Fernando E.; Gibbs, Michael A.; Mehler, William R.; Philpott, Delbert E.; Savage, Wayne

1986-01-01

Axoglial contacts were observed in an ultrastructural study of the area postrema of the cat. According to the disposition of the electron-dense projections attached to the adjoining membranes these contacts were classified as symmetrical or asymmetrical. The axon profiles contained aggregations of clear vesicles randomly distributed or grouped in clusters adjacent to the electron-dense projections. Dense core vesicles were occasionally seen. The neuroglial profiles were either astrocytic or ependymoglial in nature. The astrocytes showed a clear cytoplasm, polymorphous vesicles, mitochondria, glycogen granules, and bundles of filaments. The ependymal cells, in contrast, had a more electron-dense and granular appearance, tubular structures, irregular vesicular formations, profiles of smooth reticuloendoplasm, and filaments grouped in bundles or isolated in the cytoplasm. The possibility that these contacts might play a role in the chemical transfer from neurons to glial cells is discussed on the basis of existing biochemical data.

Morphological and populational characteristics of hemocytes of Ornithodoros moubata nymphs during the ecdysial phase.

PubMed

Kadota, K; Walter, S; Claveria, F G; Igarashi, I; Taylor, D; Fujisaki, K

2003-11-01

The ultrastructure and characteristics of hemocytes of argasid tick species, Ornithodoros moubata, during the ecdysdial phase are herein presented. Hemocyte classes/populations characterized based on their affinity with Giemsa stain and ultrastructural differences comprised the prohemocytes, nongranular cells (Nc), eosinophilic granular cells (Ec), basophilic granular cells (Bc), and unidentified cells. Significant changes/shift in the ratio of hemocyte classes/population was apparent in ticks before and after the ecdysial phase. The granule-scant basophilic granular cells (sBc) constituted the most abundant hemocyte population in the ecdysial phase. Nymphs in ecdysis showed increases in Nc and sBc and decrease in Ec, a phenomenon that was reversed in unengorged nymphs and adults ticks. The significant increase in total Bc population in ecdysis relative to nonengorged ticks clearly point to blastogenesis of Bc taking place during the ecdysial phase and Bc's important role in the process of tissue remodeling.

The acquired immunodeficiency syndrome: an ultrastructural study.

PubMed

Sidhu, G S; Stahl, R E; el-Sadr, W; Cassai, N D; Forrester, E M; Zolla-Pazner, S

1985-04-01

Blood and a variety of tissues from 97 patients with the acquired immunodeficiency syndrome (AIDS) and 25 with the AIDS prodrome were studied ultrastructurally. Tubuloreticular structures (TRS) were found in 85 per cent of the patients with AIDS and in 92 per cent of those with the prodrome. Test tube and ring-shaped forms (TRF), found in 41 per cent of the patients with AIDS and in 8 per cent of those with the prodrome, increased with disease progression. Among the patients with AIDS, as the number of sites examined per case increased, the incidence of TRS and TRF tended to approach 100 per cent, suggesting that they are present in all patients with AIDS. Other changes seen frequently were immunologic capping of blood lymphocytes, intramitochondrial iron in blood reticulocytes and marrow normoblasts, megakaryocytic immaturity and platelet phagocytosis, collections of membranous rings in hepatocytic cytoplasm, suggestive of non-A, non-B hepatitis, and proliferations and engorgement of hepatic Ito cells with lipid. The data suggest that TRS and TRF can be used as diagnostic and prognostic markers.

Charge movements and transverse tubular ultrastructure in organ cultured skeletal muscle.

PubMed

Cullen, M J; Hollingworth, S; Marshall, M W; Robson, E

1990-04-01

A study was made of charge movements and the transverse tubular systems in rat EDL and soleus muscle fibres maintained for up to five days in organ culture. In the cultured EDL muscle the maximum amount of charge moved was about one third of that in innervated muscle. Charge movements in innervated soleus fibres are small, less than 10 nC/microF, and difficult to resolve. They remain small following organ culturing. The ultrastructural study examined the concentration of junctional feet because of their proposed key role in excitation-contraction coupling. The general architecture of the triads and the spacing of the feet in both muscle types was largely unchanged by culturing. In cultured EDL muscles the small changes in feet concentration did not parallel the large fall in charge movement. The results reported here support a previous conclusion that, in mammalian muscle, there is not a simple relation between charge and feet. The stimulation of cultured soleus muscles with a fast twitch pattern of electrical activity produced no observable changes in morphology.

An ultrastructural study of sporidium formation during infection of a rhabditid nematode by large gun cells of Haptoglossa heteromorpha.

PubMed

Glockling, S L; Beakes, G W

2000-10-01

Recently fired gun cells of Haptoglossa heteromorpha, an aplanosporic nematode parasite, were examined ultrastructurally. The everted tubes of the fired cells had penetrated the cuticle of a nematode, and infective sporidia were developing inside the host body. The nematode cuticle was penetrated by the narrow, walled part of the tube below the needle chamber. The lower unwalled part of the tube tail formed the sporidium. The developing sporidium had a multilayered fibrous outer coating and the plasma membrane was separated from the wall in places. Sporidia contained biphasic membrane-bound vesicles that had been generated by the Golgi dictyosome during gun cell development. Immediately following gun cell firing, the nuclear envelope of the sporidium nucleus was not apparent, and the sporidium nucleus contained clusters of electron-dense particles concentrated in the nucleolar region. We compare the structures and organelles found in the mature gun cell with those in the fired cell and attempt to identify the membranous layers around the sporidium. Copyright 2000 Academic Press.

Ultrastructure of collagen fibers and distribution of extracellular matrix in the temporomandibular disk of the human fetus and adult.

PubMed

Takahashi, H; Sato, I

2001-12-01

We quantitatively examined the distribution of these differences in extracellular matrices (collagen types I, III, and fibronectin) and elastic fibers under confocal laser scanning microscopy and electron scanning microscopy in terms of their contribution to the mechanics of the TMJ during development and in adults. Elastic fibers were found in the anterior and posterior bands in adults aged 40 years, and a few elastic fibers in the anterior band of the disk in adults aged 80 to 90 years. The extracellular matrix contents of the TMJ disk are shown in various detected levels in the anterior, intermediate, posterior bands of TMJ disk. During development, collagen fibers are arranged in a complex fashion from 28 weeks' gestation. These ultrastructures of the embryonic TMJ are resembled to that of adults aged the 40s, however the difference in extracellular matrix distribution found in embryonic stages and adults. They might reflect the differences in function between mastication and sucking or the changes in shape and form as results of functional disorders of the TMJ.

Fungi in space--literature survey on fungi used for space research.

PubMed

Kern, V D; Hock, B

1993-09-01

A complete review of the scientific literature on experiments involving fungi in space is presented. This review begins with balloon experiments around 1935 which carried fungal spores, rocket experiments in the 1950's and 60's, satellite and moon expeditions, long-time orbit experiments and Spacelab missions in the 1980's and 90's. All these missions were aimed at examining the influence of cosmic radiation and weightlessness on genetic, physiological, and morphogenetic processes. During the 2nd German Spacelab mission (D-2, April/May 1993), the experiment FUNGI provided the facilities to cultivate higher basidiomycetes over a period of 10 d in orbit, document gravimorphogenesis and chemically fix fruiting bodies under weightlessness for subsequent ultrastructural analysis. This review shows the necessity of space travel for research on the graviperception of higher fungi and demonstrates the novelty of the experiment FUNGI performed within the framework of the D-2 mission.

Calcification of in vitro developed hypertrophic cartilage

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

Tacchetti, C.; Quarto, R.; Campanile, G.

1989-04-01

We have recently reported that dedifferentiated cells derived from stage 28-30 chick embryo tibiae, when transferred in suspension culture in the presence of ascorbic acid, develop in a tissue closely resembling hypertrophic cartilage. Ultrastructural examination of this in vitro formed cartilage showed numerous matrix vesicles associated with the extracellular matrix. In the present article we report that the in vitro developed hypertrophic cartilage undergoes calcification. We indicate a correlation between the levels of alkaline phosphatase activity and calcium deposition at different times of development. Following the transfer of cells into suspension culture and an initial lag phase, the level ofmore » alkaline phosphatase activity rapidly increased. In most experiments the maximum of activity was reached after 5 days of culture. When alkaline phosphatase activity and /sup 45/Ca deposition were measured in the same experiment, we observed that the increase in alkaline phosphatase preceded the deposition of nonwashable calcium deposits in the cartilage.« less

Changes in pituitary growth hormone cells prepared from rats flown on Spacelab 3

NASA Technical Reports Server (NTRS)

Grindeland, R.; Hymer, W. C.; Farrington, M.; Fast, T.; Hayes, C.; Motter, K.; Patil, L.; Vasques, M.

1987-01-01

The effect of exposure to microgravity on pituitary gland was investigated by examining cells isolated from anterior pituitaries of rats flown on the 7-day Spacelab 3 mission and, subsequently, cultured for 6 days. Compared with ground controls, flight cells contained more intracellular growth hormone (GH); however, the flight cells released less GH over the 6-day culture period and after implantation into hypophysectomized rats than did the control cells. Compared with control rats, glands from large rats (400 g) contained more somatotrophs (44 percent compared with 37 percent in control rats); small rats (200 g) showed no difference. No major differences were found in the somatotroph ultrastructure (by TEM) or in the pattern of the immunoactive GH variants. However, high-performance liquid chromatography fractionation of culture media indicated that flight cells released much less of a biologically active high-molecular weight GH variant, suggesting that space flight may lead to secretory dysfunction.

Expression and role of neuroglobin in rats with sepsis-associated encephalopathy.

PubMed

Zhang, Li-Na; Ai, Yu-Hang; Gong, Hua; Guo, Qu-Lian; Huang, Li; Liu, Zhi-Yong; Yao, Bo

2014-01-01

To determine the role of neuroglobin in the pathology of sepsis-associated encephalopathy and ascertain if neuroglobin has any protective effects against sepsis-associated encephalopathy. Randomized laboratory animal study. Research university animal laboratory. Two hundred and forty adult male Sprague-Dawley rats. Rats received cecal puncture and ligation (or sham) surgery to induce sepsis, then broken up into groups based on whether or not the rat developed sepsis-associated encephalopathy as determined by electroencephalograph and evoked potential recordings. The rats were then left untreated to examine the effect of sepsis-associated encephalopathy on neuroglobin, treated with a neuroglobin antisense nucleotide to block gene expression, or given hemin, a neuroglobin inducer. Following sepsis induction, diagnosis, and treatment, the brains were analyzed for both gross and ultrastructural morphology. Also, neuronal neuroglobin immunoreactivity and apoptosis (via terminal uridine nucleotide end-labeling) were examined. Blood serum levels were then analyzed for neuroglobin, superoxide dismutase, and malondialdehyde levels. We determined that sepsis-associated encephalopathy induces damage evident when examining both gross and ultrastructural morphology, as well as induces neuronal neuroglobin expression. Also, blockade of neuroglobin expression via antisense treatment will exacerbate these pathological effects, while increasing neuroglobin levels via hemin will ameliorate them. Blood analysis found that levels of superoxide dismutase and malondialdehyde mirrored the level of pathology found in the brain, while plasma neuroglobin levels reflected the amount of neuronal neuroglobin immunoreactivity. We conclude that neuroglobin is involved in the pathogenesis of sepsis-associated encephalopathy and has neuroprotective effects. We also determined that hemin has protective effects against sepsis-associated encephalopathy as well, most probably due to its effect on neuroglobin.

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...