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

Science.gov (United States)

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

2017-07-12

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

Surface topography and ultrastructural changes of mucinous carcinoma breast cells.

Science.gov (United States)

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

2007-01-01

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

Ultrastructural instability of paired helical filaments from corticobasal degeneration as examined by scanning transmission electron microscopy.

Science.gov (United States)

Ksiezak-Reding, H.; Tracz, E.; Yang, L. S.; Dickson, D. W.; Simon, M.; Wall, J. S.

1996-01-01

Paired helical filaments (PHFs) accumulate in the brains of subjects affected with Alzheimer's disease (AD) and certain other neurodegenerative disorders, including corticobasal degeneration (CBD). Electron microscope studies have shown that PHFs from CBD differ from those of AD by being wider and having a longer periodicity of the helical twist. Moreover, PHFs from CBD have been shown to be primarily composed of two rather than three highly phosphorylated polypeptides of tau (PHF-tau), with these polypeptides expressing no exons 3 and 10. To further explore the relationship between the heterogeneity of PHF-tau and the appearance of abnormal filaments, the ultrastructure and physical parameters such as mass per unit length and dimensions were compared in filaments from CBD and AD using high resolution scanning transmission electron microscopy (STEM). Filament-enriched fractions were isolated as Sarcosyl-insoluble pellets and for STEM studies, samples were freeze-dried without prior fixation or staining. Ultrastructurally, PHFs from CBD were shown to be a heterogeneous population as double- and single-stranded filaments could be identified based on their width and physical mass per unit length expressed in kilodaltons (kd) per nanometer (nm). Less abundant, double-stranded filaments had a maximal width of 29 nm and a mass per unit length of 133 kd/nm, whereas three times more abundant single-stranded filaments were 15 nm wide and bad a mass per unit length of 62 kd/nm. Double-stranded filaments also displayed a distinct axial region of less dense mass, which appeared to divide the PHFs into two protofilament-like strands. Furthermore, these filaments were frequently observed to physically separate along the long axis into two single strands or to break longitudinally. In contrast, PHFs from AD were ultrastructurally stable and uniform both in their width (22 nm) and physical mass per unit length (104 kd/nm). The ultrastructural features indicate that filaments of

Ultrastructural myocardial changes in seven cats with spontaneous hypertrophic cardiomyopathy

DEFF Research Database (Denmark)

Christiansen, Liselotte Bruun; Prats Gavalda, Clara; Hyttel, Poul

2015-01-01

OBJECTIVES: Hypertrophic cardiomyopathy (HCM) is the most common heart disease in cats and shares clinical and pathological characteristics with human HCM. Little is known about the pathogenic mechanisms underlying development of spontaneous feline HCM. ANIMALS: The study population consisted...... of seven cats diagnosed with HCM and eight age-matched cats with no evidence of cardiac disease. METHODS: Fresh myocardial biopsies taken from the middle of the left ventricular posterior free wall were obtained and examined with transmission electron microscopy. RESULTS: Electron microscopic examination...... showed ultrastructural aberrations of the myocardial cytoarchitecture and of the interstitium in the seven cats with HCM. In the most severely affected cats the myofibrils were disorganized and subsarcolemmal mitochondria were depleted. In control cats, contraction band artifacts were commonly seen...

Ultrastructural alterations in adult Schistosoma mansoni caused by artemether

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Shuhua Xiao

2002-07-01

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

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

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

2018-01-23

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

Ultrastructural demonstration of chemical modification of melanogenesis in hairless mouse skin

International Nuclear Information System (INIS)

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

1982-01-01

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

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

Science.gov (United States)

Chwil, Mirosława; Chwil, Stanisław

2012-10-01

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

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

OpenAIRE

Ekici,Nuran; Dane,Feruzan; Olgun,Göksel

2009-01-01

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

Ultrastructural analysis of anastomosis group 9 of Rhizoctonia solani

International Nuclear Information System (INIS)

Cedeno, L; Palacios Pru, E

1996-01-01

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

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

Science.gov (United States)

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

2012-04-01

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

Familial atrophia maculosa varioliformis cutis: an ultrastructural study.

Science.gov (United States)

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

2001-01-01

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

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

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Joanna Czerwik-Marcinkowska

2011-08-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2011-05-15

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

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

International Nuclear Information System (INIS)

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

2011-01-01

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

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

Science.gov (United States)

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

2012-01-01

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

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

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Trinh Hermanns-Lê

2012-01-01

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

An ultrastructural examination of irradiated, immunizing schistosomula of Schistosoma mansoni during their extended stay in the lungs

International Nuclear Information System (INIS)

Mastin, A.; Wilson, R.A.; Bickle, Q.D.

1985-01-01

An ultrastructural study has been performed on radiation-attenuated parasites fixed in situ during their extended stay in the lungs. At day 7 post-infection all parasites were located within blood vessels. In contrast to normally migrating parasites, at days 13 and 21 post-infection the majority of radiation-attenuated parasites were lying free within alveoli. It appeared that radiation-attenuated parasites had undergone the normal developmental changes associated with the lung-stage of migration. No ultrastructural evidence was found to suggest why schistosomula failed to migrate further and instead burst into alveoli. No parasites observed on day 7 post-infection were associated with a host inflammatory reaction. At day 13, inflammation was noticeable but could have been a response as much to pulmonary tissue damage as to the presence of parasites. At day 21 post-infection some parasites were internally disrupted but were not associated with host inflammatory reactions and had intact tegumental surfaces. One parasite was observed at day 21 with an adherent neutrophil infiltrate and extensive tegumental damage. The relevance of persisting lung-stage parasites to the induction of resistance to challenge is discussed. (author)

Inter-relationships of haplosporidians deduced from ultrastructural studies

NARCIS (Netherlands)

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

2009-01-01

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

[Tooth macromorphological and ultrastructural analysis of osteological material from the medieval locality of St. Panteleimon Church in Nis].

Science.gov (United States)

Mitić, Nadica; Mitić, Aleksandar; Mitić, Vladimir; Savić, Vojin; Nikolić, Marija

2010-01-01

Analysis of macromorphological and ultrastructural tooth characteristics of osteological material from the medieval site of St. Pantaleimon Church in Nis provides us with insight on the life, nutrition and habits of medieval population, as well as the structure and composition of their teeth. The aim of this research, based on the tooth inspection of skeletal remains from the medieval site of St. Pantaleimon Church in Nis, was to analyze macromorphological characteristics, ultrastructure of the dental tissue of maxillary and mandibular molars, canines and incisors, as well as their chemical composition. Macromorphological and ultrastructural analysis of the dental tissue of osteological material dating from the 12th century included 1312 teeth with advanced abrasion. Macromorphological changes were detected by using a dental mirror, probe and radiography. After irrigation, the teeth were prepared using the standard procedure and analyzed by scanning electronic microscopy (JEOL-JSM-5300). Chemical analysis was done by expanded downscaling (EDS) method for Mg, P, Ca. The analysis detected second degree abrasions of all teeth in individuals aged 20-25 years. Third and fourth degree abrasions of teeth were detected in individuals aged over 40 years. Ultrastructural analysis showed a complete obliteration of dentin tubules and pulp of the lower incisors, the apposition of intratubular dentin inside the tubules, as well as extensive deformity and loss of dentin structure on molars with preserved pulp volume and nerve fiber calcification. The calcification of nerve fibers showed that the formation of intratubular dentin was proportional with the biological potential of pulp and the degree of abrasion, and inversely proportional with the size of dentin surface. Chemical analysis showed that in the analyzed teeth Ca composition was slightly lower than that in the control group, P composition was almost identical, while Mg composition was multiply increased in comparison to

Ultrastructural evaluation of multiple pass low energy versus single pass high energy radio-frequency treatment.

Science.gov (United States)

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

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

Science.gov (United States)

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

1983-01-01

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

Histopathological, Ultrastructural and Apoptotic Changes in Diabetic Rat Placenta

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Mehmet Gül

2015-09-01

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

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

Science.gov (United States)

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

2014-04-01

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

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

Science.gov (United States)

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

2017-02-01

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

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

Science.gov (United States)

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

2017-03-01

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

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

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Hemminger Bradley M

2009-08-01

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

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

African Journals Online (AJOL)

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

Gamma irradiation induced ultrastructural changes in Paracoccidioides brasiliensis yeast cells

International Nuclear Information System (INIS)

Demicheli, Marina C.; Andrade, Antero S.R.; Goes, Alfredo Miranda

2007-01-01

Paracoccidioides brasiliensis is a thermally dimorphic fungus agent of paracoccidioidomycosis, a deep-seated systemic infection of humans with high prevalence in Latin America. Up to the moment no vaccine has still been reported. Ionizing radiation can be used to attenuate pathogens for vaccine development and we have successfully attenuated yeast cells of P. brasiliensis by gamma irradiation. The aim of the present study was to examine at ultrastructural level the effects of gamma irradiation attenuation on the morphology of P. brasiliensis yeast cells. P. brasiliensis (strain Pb-18) cultures were irradiated with a dose of 6.5 kGy. The irradiated cells were examined by scanning and also transmission electron microscopy. When examined two hours after the irradiation by scanning electron microscopy the 6.5 kGy irradiated cells presented deep folds or were collapsed. These lesions were reversible since examined 48 hours after irradiation the yeast have recovered the usual morphology. The transmission electron microscopy showed that the irradiated cells plasma membrane and cell wall were intact and preserved. Remarkable changes were found in the nucleus that was frequently in a very electrodense form. A extensive DNA fragmentation was produced by the gamma irradiation treatment. (author)

Dietary adaptions in the ultrastructure of dinosaur dentine.

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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).

Giardia agilis: Ultrastructure of the Trophozoites in the Frog Intestine

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Maria Inês L Sogayar

1998-05-01

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

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

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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.

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

Science.gov (United States)

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

2014-07-01

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

A study of the soil flagellate Phalansterium solitarium Sandon 1924 with preliminary data on its ultrastructure

DEFF Research Database (Denmark)

Ekelund, Flemming

2002-01-01

Phalansterium solitarium Sandon 1924, a common soil flagellate, was isolated and a Sandon 1924, a common soil flagellate, was isolated and a clonal culture was examined using light and electron microscopy. The first preliminary observations of its ultrastructure show that the cells of Ph....... solitarium have the same main characters as an earlier investigated species of the genus, Ph. digitatum Stein 1878, including a collarlike structure surrounding the basis of the single emerging flagellum, tubular cristae, a single basal body, surrounded by x, y and z zones with radiating microtubules...

Ultrastructural Changes in the Liver of Intravenous Heroin Addicts

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Goran Ilić

2010-02-01

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

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

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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.

Effect of the bendiocarb on the ultrastructure of rabbit skeletal muscle

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Katarína Holovská

2017-01-01

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

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

Science.gov (United States)

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

2012-11-01

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

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

Science.gov (United States)

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

2007-10-01

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

Ultrastructure of respiratory tract epithelium following irradiation or application of cytostatics

International Nuclear Information System (INIS)

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

1988-01-01

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

Acinar cell ultrastructure after taurine treatment in rat acute necrotizing pancreatitis

International Nuclear Information System (INIS)

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

2006-01-01

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

Ultrastructural study of chromoplast components rich in glycolipids

OpenAIRE

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

2001-01-01

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

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

Science.gov (United States)

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

2017-08-01

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

Ultrastructural changes and nestin expression accompanying compensatory renal growth after unilateral nephrectomy in adult rats

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Eladl MA

2017-02-01

Full Text Available Mohamed Ahmed Eladl,1,2 Wael M Elsaed,2,3 Hoda Atef,4 Mohamed El-Sherbiny2 1Department of Basic Medical Sciences, University of Sharjah, Sharjah, United Arab Emirates; 2Anatomy and Embryology Department, Faculty of Medicine, Mansoura University, Mansoura, Egypt; 3Anatomy and Embryology Department, Faculty of Medicine, Taibah University, Madinah, Saudi Arabia; 4Department of Histology, University of Mansoura, Mansoura, Egypt Background: Several renal disorders affect the glomerular podocytes. Compensatory structural and functional changes have been observed in animals that have undergone unilateral renal ablation. These changes occur as a pliant response to quench the increased functional demand to maintain homeostasis of fluid and solutes. Nestin is an intermediate filament protein present in the glomerular podocytes of the adult kidney and is linked with the maintenance of its foot process structure. Structural changes in the podocytes ultimately restructure the filtration barrier. Very few studies related to the ultrastructural and histopathologic changes of the podocytes are documented. The present study aimed to assess the histopathologic changes at the ultrastructural level in the adapted kidney at different time intervals following unilateral renal ablation in adult rats and its relation with nestin.Methods: Forty-eight rats were divided into four groups (n=12 in each group. The animals of Group A were control naïve rats, while the group B, group C and group D animals underwent left unilateral nephrectomy and the remaining right kidney was removed on days 10, 20 and 30, respectively. Each group included four sham-operated rats, which were sacrificed at the same time as the naïve rats. Each nephrectomized sample was weighed and its sections were subjected to hematoxylin and eosin examination, transmission electron microscopic study as well as immunostaining using the intermediate filament protein nestin.Results: No difference was found

Ultrastructural and Molecular Changes in the Developing Small Intestine of the Toad Bufo regularis

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S. A. Sakr

2014-01-01

Full Text Available The ontogenetic development of the small intestine of the toad Bufo regularis was investigated using twofold approaches, namely, ultrastructural and molecular. The former has been done using transmission electron microscope and utilizing the developmental stages 42, 50, 55, 60, 63, and 66. The most prominent ultrastructural changes were recorded at stage 60 and were more evident at stage 63. These included the appearance of apoptotic bodies/nuclei within the larval epithelium, the presence of macrophages, swollen mitochondria, distorted rough endoplasmic reticulum, chromatin condensation, and irregular nuclear envelop, and the presence of large vacuoles and lysosomes. The molecular investigation involved examining DNA content and fragmentation. The results showed that the DNA content decreased significantly during the metamorphic stages 60 and 63 compared with both larval (50 and 55 and postmetamorphic (66 stages. The metamorphic stages (60 and 63 displayed extensive DNA laddering compared with stages 50, 55, and 66. The percentage of DNA damage was 0.00%, 12.91%, 57.26%, 45.48%, and 4.43% for the developmental stages 50, 55, 60, 63, and 66, respectively. In conclusion, the recorded remodeling of the small intestine represents a model for clarifying the mechanism whereby cell death and proliferation are controlled.

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

OpenAIRE

Sogayar,Maria Inês L.; Gregório,Elisa Aparecida

1989-01-01

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

Influence of nitrogen deficiency on photosynthesis and chloroplast ultrastructure of pepper plants (Research Note

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S. DONCHEVA

2008-12-01

Full Text Available Pepper plants (Capsicum annuum L. cv. Zlaten Medal were grown on nutrient solution without nitrogen, and photosynthetic response of plants was examined by determination of leaf CO2 fixation and chlorophyll and carotenoid contents. The absence of nitrogen in the medium resulted in a decrease of the leaf area and of plant biomass accumulation, and in an increase of the root-shoot dry weight ratio. The photosynthetic activity and chlorophyll and carotenoid contents decreased significantly under nitrogen deprivation. Examination of nitrogen deficient leaves by transmission electron microscopy showed dramatic changes in chloroplast ultrastructure. The proportion of starch granules and plastoglobules in the stroma matrix was increased and internal membrane system was greatly reduced. It seems that nitrogen plays an important role in the formation of chloroplast structure and hence to the photosynthetic intensity and productivity of pepper plants.

Ultrastructure and properties of Paecilomyces lilacinus spores

Energy Technology Data Exchange (ETDEWEB)

Holland, R.J.; Gunasekera, T.S. [Macquarie Univ., Dept. of Biological Sciences, Sydney (Australia); Williams, K.L. [Proteome Systems Ltd., Sydney (Australia); Nevalainen, K.M.H. [Dept. of Biological Sciences, Macquarie University, Sydney (Australia)

2002-10-01

Strains of the filamentous soil fungus Paecilomyces lilacinus are currently being developed for use as biological control agents against root-knot, cyst, and other plant-parasitic nematodes. The inoculum applied in the field consists mainly of spores. This study was undertaken to examine the size, ultrastructure, and rodlet layers of P. lilacinus spores and the effect of the culture method on structural and functional spore properties. A rodlet layer was identified on aerial spores only. Other differences noted between aerial spores and those produced in submerged culture included the size and appearance of spores and thickness of spore coat layers when examined with transmission electron microscopy. The two spore types differed in UV tolerance, with aerial spores being less sensitive to environmentally relevant UV radiation. Also, viability after drying and storage was better with the aerial spores. Both spore types exhibited similar nematophagous ability. (author)

Ultrastructure and properties of Paecilomyces lilacinus spores

International Nuclear Information System (INIS)

Holland, R.J.; Gunasekera, T.S.; Williams, K.L.; Nevalainen, K.M.H.

2002-01-01

Strains of the filamentous soil fungus Paecilomyces lilacinus are currently being developed for use as biological control agents against root-knot, cyst, and other plant-parasitic nematodes. The inoculum applied in the field consists mainly of spores. This study was undertaken to examine the size, ultrastructure, and rodlet layers of P. lilacinus spores and the effect of the culture method on structural and functional spore properties. A rodlet layer was identified on aerial spores only. Other differences noted between aerial spores and those produced in submerged culture included the size and appearance of spores and thickness of spore coat layers when examined with transmission electron microscopy. The two spore types differed in UV tolerance, with aerial spores being less sensitive to environmentally relevant UV radiation. Also, viability after drying and storage was better with the aerial spores. Both spore types exhibited similar nematophagous ability. (author)

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

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Reham Wasfi

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

Ultrastructural hepatocellular features associated with severe hepatic lipidosis in cats.

Science.gov (United States)

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

1993-05-01

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

Ultrastructural Morphology of Sperm from Human Globozoospermia

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Giuseppe Ricci

2015-01-01

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

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

International Nuclear Information System (INIS)

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

1998-01-01

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

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

Science.gov (United States)

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

1988-11-01

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

Ultrastructural and biochemical studies on formation of calcium oxalate in plants

International Nuclear Information System (INIS)

Abdelmottaleb, A.M.

1989-01-01

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

Early studies of placental ultrastructure by electron microscopy

DEFF Research Database (Denmark)

Carter, A M; Enders, A C

2016-01-01

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

Ultrastructural investigation on radiation resistant microbial isolates of bacillus coagulans

International Nuclear Information System (INIS)

Tawfik, Z.S.

1992-01-01

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

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

Science.gov (United States)

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

2015-11-01

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

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

Energy Technology Data Exchange (ETDEWEB)

Schneider, Jerusa, E-mail: jerusaschneider@hotmail.com [Departamento de Ciência do Solo, Universidade Federal de Lavras (UFLA), PO Box 3037, Lavras, Minas Gerais, 37200-000 (Brazil); Labory, Claudia Regina Gontijo [Departamento de Fitopatologia, Universidade Federal de Lavras, PO Box 3037, Lavras, Minas Gerais, 37200-000 (Brazil); Rangel, Wesley Melo [Departamento de Ciência do Solo, Universidade Federal de Lavras (UFLA), PO Box 3037, Lavras, Minas Gerais, 37200-000 (Brazil); Alves, Eduardo [Departamento de Fitopatologia, Universidade Federal de Lavras, PO Box 3037, Lavras, Minas Gerais, 37200-000 (Brazil); Guilherme, Luiz Roberto Guimarães [Departamento de Ciência do Solo, Universidade Federal de Lavras (UFLA), PO Box 3037, Lavras, Minas Gerais, 37200-000 (Brazil)

2013-11-15

Highlights: ► Inoculation of L. leucocephala improved plant growth in high-As soils. ► Plants inoculated with Glomus clarum were less sensitive to As. ► Ultrastructural changes in leaves of L. leucocephala. ► Modified structures in intracellular spaces in plants inoculated with G. clarum. ► Cell disruption and stacking of root cell walls at high As concentrations. -- Abstract: Many studies demonstrate the potential application of arbuscular mycorrhizal fungi (AMF) for remediation purposes, but little is known on AMF potential to enhance plant tolerance to arsenic (As) and the mechanisms involved in this process. We carried anatomical and ultrastructural studies to examine this symbiotic association and the characteristics of shoots and roots of Leucaena leucocephala in As-amended soils (35 and 75 mg As dm{sup −3}). The experiment used 3 AMF isolates from uncontaminated soils: Acaulospora morrowiae, Glomus clarum, and Gigaspora albida; a mixed inoculum derived from combining these 3 isolates (named Mix AMF); and, 3 AMF isolates from As-contaminated areas: A. morrowiae, G. clarum and Paraglomus occultum. Phytotoxicity symptoms due to arsenic contamination appeared during plant growth, especially in treatments without AMF application. Inoculation with G. clarum and the mixture of species (A. morrowiae, G. albida, and G. clarum) resulted in better growth of L. leucocephala in soils with high As concentrations, as well as significant As removal from the soil, showing a potential for using AMF in phytoextraction. Light microscopy (LS), transmission (TEM) and scanning electron microscopies (SEM) studies showed the colonization of the AMF in plant tissues and damage in all treatments, with ultrastructural changes being observed in leaves and roots of L. leucocephala, especially with the addition of 75 mg dm{sup −3} of As.

Ultrastructural characteristics of nurse cell-larva complex of four species of Trichinella in several hosts

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Sacchi L.

2001-06-01

Full Text Available The nurse cell-larva complex of nematodes of the genus Trichinella plays an Important role in the survival of the larva in decaying muscles, frequently favouring the transmission of the parasite in extreme environmental conditions. The ultrastructure of the nurse cell-larva complex in muscles from different hosts infected with T. nativa (a walrus and a polar bear, T. spiralis (horses and humans, T. pseudospiralis (a laboratory mouse and T. papuae (a laboratory mouse were examined. Analysis with transmission electron microscope showed that the typical nurse cell structure was present in all examined samples, irrespective of the species of larva, of the presence of a collagen capsule, of the age of infection and of the host species, suggesting that there exists a molecular mechanism that in the first stage of larva invasion is similar for encapsulated and non-encapsulated species.

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

Science.gov (United States)

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

2017-07-01

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

Ultrastructural studies of Biomphalaria glabrata (Say, 1818) embryo

International Nuclear Information System (INIS)

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

1988-09-01

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

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

International Nuclear Information System (INIS)

Ali, Mumtaz.

1975-01-01

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

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

International Nuclear Information System (INIS)

Abd El Azeem, M.G.

2011-01-01

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

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

Science.gov (United States)

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

2013-01-01

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

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

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Myroslava Stakhiv

2013-04-01

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

Ultrastructural changes in mollicutes induced by the peptide antibiotic herbicolin A

DEFF Research Database (Denmark)

Birkelund, Svend; Freundt, A; Christiansen, Gunna

1986-01-01

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

Comparative ultrastructure of the cuticle of trichostrongyle nematodes.

Science.gov (United States)

Beveridge, I; Durette-Desset, M C

1994-09-01

The ultrastructure of the cuticle was examined in Austrostrongylus victoriensis, Patricialina birdi and Woolleya monodelphis (Herpetostrongylidae) from marsupials, Paraustrostrongylus ratti (Herpetostrongylidae) from rodents, Nippostrongylus magnus and Odilia bainae (Heligmonellidae) from rodents, Cooperia oncophora and Camelostrongylus mentulatus (Trichostrongylidae) from ruminants, and Nematodirus spathiger (Molineidae) from ruminants. The principal cuticular layers described previously were present in all species investigated. Major differences in the shape and composition of cuticular struts were observed as well as differences in components of the median zone of the cuticle, including the fluid-filled regions present in several species. Several different types of strut were observed. Although strut structure within the Heligmonellidae appeared to be constant, there were variations within both the Herpetostrongylidae and Trichostrongylidae. In Nem. spathiger the cuticular ridges lacked struts. The diversity of structures found in the species examined suggests that more extensive comparative studies of the trichostrongyle cuticle are warranted.

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

Institute of Scientific and Technical Information of China (English)

无

2003-01-01

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

Air pollution effects on the ultrastructure of Phlomis fruticosa mesophyll cells

Energy Technology Data Exchange (ETDEWEB)

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

1987-04-01

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

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

International Nuclear Information System (INIS)

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

1994-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

1994-12-31

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

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

Directory of Open Access Journals (Sweden)

Vera Luiza Capelozzi

2010-01-01

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

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

Science.gov (United States)

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

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

NARCIS (Netherlands)

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

2014-01-01

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

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

Science.gov (United States)

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

2016-06-01

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

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

Science.gov (United States)

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

2015-03-01

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

Ultrastructural and physiological responses of potato (Solanum tuberosum L.) plantlets to gradient saline stress

Science.gov (United States)

Gao, Hui-Juan; Yang, Hong-Yu; Bai, Jiang-Ping; Liang, Xin-Yue; Lou, Yan; Zhang, Jun-Lian; Wang, Di; Zhang, Jin-Lin; Niu, Shu-Qi; Chen, Ying-Long

2015-01-01

Salinity is one of the major abiotic stresses that impacts plant growth and reduces the productivity of field crops. Compared to field plants, test tube plantlets offer a direct and fast approach to investigate the mechanism of salt tolerance. Here we examined the ultrastructural and physiological responses of potato (Solanum tuberosum L. c.v. “Longshu No. 3”) plantlets to gradient saline stress (0, 25, 50, 100, and 200 mM NaCl) with two consequent observations (2 and 6 weeks, respectively). The results showed that, with the increase of external NaCl concentration and the duration of treatments, (1) the number of chloroplasts and cell intercellular spaces markedly decreased, (2) cell walls were thickened and even ruptured, (3) mesophyll cells and chloroplasts were gradually damaged to a complete disorganization containing more starch, (4) leaf Na and Cl contents increased while leaf K content decreased, (5) leaf proline content and the activities of catalase (CAT) and superoxide dismutase (SOD) increased significantly, and (6) leaf malondialdehyde (MDA) content increased significantly and stomatal area and chlorophyll content decline were also detected. Severe salt stress (200 mM NaCl) inhibited plantlet growth. These results indicated that potato plantlets adapt to salt stress to some extent through accumulating osmoprotectants, such as proline, increasing the activities of antioxidant enzymes, such as CAT and SOD. The outcomes of this study provide ultrastructural and physiological insights into characterizing potential damages induced by salt stress for selecting salt-tolerant potato cultivars. PMID:25628634

Olmesartan Attenuates Tacrolimus-Induced Biochemical and Ultrastructural Changes in Rat Kidney Tissue

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Naif O. Al-Harbi

2014-01-01

Full Text Available Tacrolimus, a calcineurin inhibitor, is clinically used as an immunosuppressive agent in organ transplantation, but its use is limited due to its marked nephrotoxicity. The present study investigated the effect of olmesartan (angiotensin receptor blocker on tacrolimus-induced nephrotoxicity in rats. A total of 24 rats were divided into four groups, which included control, tacrolimus, tacrolimus + olmesartan, and olmesartan groups. Tacrolimus-induced nephrotoxicity was assessed biochemically and histopathologically. Tacrolimus significantly increased BUN and creatinine level. Treatment with olmesartan reversed tacrolimus-induced changes in the biochemical markers (BUN and creatinine of nephrotoxicity. Tacrolimus significantly decreased GSH level and catalase activity while increasing MDA level. Olmesartan also attenuated the effects of tacrolimus on MDA, GSH, and catalase. In tacrolimus group histological examination showed marked changes in renal tubule, mitochondria, and podocyte processes. Histopathological and ultrastructural studies showed that treatment with olmesartan prevented tacrolimus-induced renal damage. These results suggest that olmesartan has protective effects on tacrolimus-induced nephrotoxicity, implying that RAS might be playing role in tacrolimus-induced nephrotoxicity.

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

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Amber K Gillett

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

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

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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.

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

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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

Ultrastructural diversity between centrioles of eukaryotes.

Science.gov (United States)

Gupta, Akshari; Kitagawa, Daiju

2018-02-16

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

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

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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.

Ultrastructure of the harmful unarmored dinoflagellate Cochlodinium polykrikoides (Dinophyceae) with reference to the apical groove and flagellar apparatus

DEFF Research Database (Denmark)

Iwataki, Mitsunori; Hansen, Gert; Moestrup, Øjvind

2010-01-01

The external and internal ultrastructure of the harmful unarmored dinoflagellate Cochlodinium polykrikoides Margalef has been examined with special reference to the apical groove and three-dimensional structure of the flagellar apparatus. The apical groove is U-shaped and connected to the anterior...

Ultrastructural studies of synthetic apatite crystals.

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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.

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

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

1975-02-01

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

The ultrastructural changes in the liver cells induced by high doses of Benzodiazepine Tranquilizing drugs: An experimental transmission electron microscopic study on male guinea pigs

International Nuclear Information System (INIS)

Bisher, Ameen S. Ahmad

2008-01-01

Benzodiazepines are tranquilizing psychotropic drugs. Unfortunately, despite their therapeutic benefits, they are illegally consumed in high doses by some addicts to reach a sedative, exhilarative and euphoria state similar to that produced by narcotic substances. The present study, using transmission electron microscope on male guinea pigs, aims to investigate the potential ultrastructural changes in the liver cells induced by the high doses of Benzodiazepines. Animals in three treated groups administrated a daily combined dose consisted of (10mg Alprazolam with 10mg Diazepam/day/animal) for three different treatment periods: 7, 15, and 25 days. The ultrastructural examination of the hepatocytes of the animals treated for 15 days showed limited changes in the form of marginal heterochromatine accompanied with marginal nucleoli enlargement. On the other hand, severe ultrastructural damages are observed in the animals treated for 25 days, which appeared in the following various patterns: fatty degeneration of the hepatocytes as indicated by the accumulation of large number of lipid droplets in the cytoplasm, marked nuclear atrophy in some necrotic hepatocytes, massive nuclear degeneration in other hepatocytes, mitochondrial damages in the form of cristea destruction accompanied with abnormal oval shape, massive lysis of the cytoplasmic organelles with severe plasma membrane rupture. In conclusion, the observed ultrastructural damages in the present study may refer to the potential hepatotoxic effects of the high dose of Benzodiazepins. It is recommended that much more official restrictions should be applied on the pharmacies sector to prevent any illegal selling of these drugs in order to prevent abusers from obtaining them, as unfortunately in some developing countries the illegal selling of these drugs is known to occur due to the absence of official control. (author)

Ultrastructure and pathology of desmoplastic small round cell tumor

International Nuclear Information System (INIS)

Xu Bin; Wang Bo; Gu Junlian; Li Xin; Li Yang

2010-01-01

Objective: To observe the change of ultrastructure and pathology of desmoplastic small round cell tumor (DSRCT) and recognize the characteristics of DSRCT and improve the standard of diagnosis. Methods: One case of primary DSRCT in right leg was observed by light microscope, immunohistochemical method and electron microscope and analyzed with review of the literatures. Results: The size of tumor was 3.2 cm x 2.4 cm x 1.3 cm with gray-yellow on cross-section. Foci of hemorrhage and necrosis were noted. Under light microscope, the tumor was composed of sharply demarcated nests of small rounded or oval cells. The cellular aggregates were surrounded and separated by abundant fibrous connective tissue. The tumor cells were uniform in size and shape, and showed small to moderate amounts of pale cytoplasm with indistinct cell borders. The nuclei were round to oval, with clumped chromatin and marked hyperchromasia. Some cells had one or two indistinct nucleoli. Numerous mitotic figures and areas of necrosis were dentified. The immunohistochemical results showed that the tumor cells were strongly positive for CK, EMA and NSE. There was focal positive staining for desmin with a perinuclear dot-like pattern. However, the tumor cells were negative for CgA, Myogenin, Syn, LCA, SMA, S-100, NF, GFAP, HMB45, HHF-35, CD3, CD10, Actin, CD99, and CD20. Under electron microscope, the tumor cells showed paranuclear cytoplasmic intermediate filaments arranging in globular or whorl array. Conclusion: DSRCT occurs both in the abdomen and at other sites. The patients with DSRCT range widely in age. DSRCT has distinctive histopathologic and ultrastructural features. This tumor shows immunohistochemical feature of epithelial, mesenchymal as well as neural multidirectional differentiation. RT-PCR may be served as an important diagnostic adjunct for DSRAT. The prognosis of the patients with DSRCT is very poor. (authors)

Ultrastructural morphometry of parotid acinar cells following fractionated irradiation

International Nuclear Information System (INIS)

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

1997-01-01

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

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

OpenAIRE

Raiha Qadri; A. Mahmood; Mohammad Athar

2007-01-01

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

Perinatal exposure to lead induces morphological, ultrastructural and molecular alterations in the hippocampus

International Nuclear Information System (INIS)

Baranowska-Bosiacka, I.; Strużyńska, L.; Gutowska, I.; Machalińska, A.; Kolasa, A.; Kłos, P.; Czapski, G.A.; Kurzawski, M.; Prokopowicz, A.; Marchlewicz, M.

2013-01-01

Highlights: ► Pre- and neonatal Pb exposure decreased the number of hippocampal neurons. ► Lead caused ultrastructural alterations in CA1 region of hippocampus. ► Hippocampus is highly vulnerable to low level perinatal Pb exposure. ► Lead decreased BDNF level in the developing brain. ► Decreased Bax/Bcl2 ratio may protect hippocampus against Pb-induced apoptosis. -- Abstract: The aim of this paper is to examine if pre- and neonatal exposure to lead (Pb) may intensify or inhibit apoptosis or necroptosis in the developing rat brain. Pregnant experimental females received 0.1% lead acetate (PbAc) in drinking water from the first day of gestation until weaning of the offspring; the control group received distilled water. During the feeding of pups, mothers from the experimental group were still receiving PbAc. Pups were weaned at postnatal day 21 and the young rats of both groups then received only distilled water until postnatal day 28. This treatment protocol resulted in a concentration of Pb in rat offspring whole blood (Pb-B) below the threshold of 10 μg/dL, considered safe for humans.We studied Casp-3 activity and expression, AIF nuclear translocation, DNA fragmentation, as well as Bax, Bcl-2 mRNA and protein expression as well as BDNF concentration in selected structures of the rat brain: forebrain cortex (FC), cerebellum (C) and hippocampus (H). The microscopic examinations showed alterations in hippocampal neurons.Our data shows that pre- and neonatal exposure of rats to Pb, leading to Pb-B below 10 μg/dL, can decrease the number of hippocampus neurons, occurring concomitantly with ultrastructural alterations in this region. We observed no morphological or molecular features of severe apoptosis or necrosis (no active Casp-3 and AIF translocation to nucleus) in young brains, despite the reduced levels of BDNF. The potential protective factor against apoptosis was probably the decreased Bax/Bcl-2 ratio, which requires further investigation. Our

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

Science.gov (United States)

Papa, V; Costa, R; Cenacchi, G

2016-06-01

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

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

OpenAIRE

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

2007-01-01

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

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

Science.gov (United States)

2015-01-01

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

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

Science.gov (United States)

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

1987-02-01

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

Ultrastructural and physiological responses of potato (Solanum tuberosum L. plantlets to gradient saline stress

Directory of Open Access Journals (Sweden)

Hui-Juan eGao

2015-01-01

Full Text Available Salinity is one of the major abiotic stresses that impacts plant growth and reduces the productivity of field crops. Compared to field plants, test tube plantlets offer a direct and fast approach to investigate the mechanism of salt tolerance. Here we examined the ultrastructural and physiological responses of potato (Solanum tuberosum L. c.v. ‘Longshu No. 3’ plantlets to gradient saline stress (0, 25, 50, 100 and 200 mM NaCl with two consequent observations (two and six weeks, respectively. The results showed that, with the increase of external NaCl concentration and the duration of treatments, (1 the number of chloroplasts and cell intercellular spaces markedly decreased, (2 cell walls were thickened and even ruptured, (3 mesophyll cells and chloroplasts were gradually damaged to a complete disorganization containing more starch, (4 leaf Na and Cl contents increased while leaf K content decreased, (5 leaf proline content and the activities of catalase (CAT and superoxide dismutase (SOD increased significantly, and (6 leaf malondialdehyde (MDA content increased significantly and stomatal area and chlorophyll content decline were also detected. Severe salt stress (200 mM NaCl inhibited plantlet growth. These results indicated that potato plantlets adapt to salt stress to some extent through accumulating osmoprotectants, such as proline, increasing the activities of antioxidant enzymes, such as CAT and SOD. The outcomes of this study provide ultrastructural and physiological insights into characterizing potential damages induced by salt stress for selecting salt-tolerant potato cultivars.

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

Science.gov (United States)

Mahmoud, Y I; Hegazy, H G

2016-01-01

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

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

International Nuclear Information System (INIS)

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

2006-01-01

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

Metschnikowia cf. typographi and other pathogens from the bark beetle Ips sexdentatus - Prevalence, histological and ultrastructural evidence, and molecular characterization

DEFF Research Database (Denmark)

Kleespies, Regina G; Lim, Young Woon; Tkaczuk, Cezary

2017-01-01

Ips sexdentatus (six-spined engraver beetle) from Austria and Poland were dissected and examined for the presence of pathogens. Specimens collected in Austria were found to contain the ascomycetous fungus Metschnikowia cf. typographi. Infection rates ranged from 3.6% to 26.8% at different...... collection sites. M. cf. typographi infected midguts were investigated by histological, ultrastructural and molecular techniques. Extraordinary ultrastructural details are shown, such as ascospores with bilateral flattened flanks resembling alar rims at both sides of their attenuating tube-like ends....... The eugregarine Gregarina typographi was diagnosed most frequently. Infection rates of all I. sexdentatus specimens ranged from 21.4% to 71.9% in Austria and 54.1% to 68.8% in Poland. Other entomopathogenic protists, bacteria, or viruses were not detected....

Ultrastructural study of primordial germ cells, oogonia and oocytes in goat fetus

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S.M Banan Khojasteh

2009-02-01

Full Text Available According to morphological evidences, primordial germ cells (PGCs are derived from the caudal endoderm of the yolk sac and migrate to embryonic gonads. After entering the gonads, first they differentiate to oogonia and then to oocytes. In the present study, ultrastructure of PGCs, oogonia and oocytes has been examined. Tissue samples were collected from posterior parts of the yolk sacs of fetuses in the early stages of development (with age of less than 1 month, and also gonads of fetuses at later developmental stages (with age of more than 1 month. Samples were studied using transmission electron microscopy after fixation, washing with buffers, dehydration, embedding and staining with uranyl acetate and lead citrate. The Results indicated that PGCs were large with oval to spherical nuclei, reticular chromatin with nucleoli, and there were plenty of glycogen and also different organelles in their cytoplasm. Oogonia showed active mitotic divisions. These cells had regular plasma membranes and were observed as cellular clusters with spherical shape, euchromatin nucleus containing one or more nucleoli, round mitochondria and vacuoles with different sizes in cytoplasm. Oocytes had larger sizes in comparison with oogonia but didn't show cellular clusters.

EVALUATION OF THE ULTRASTRUCTURE OF THE SMALL INTESTINE OF HIV INFECTED CHILDREN BY TRANSMISSION AND SCANNING ELECTRONIC MICROSCOPY

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Christiane Araujo Chaves LEITE

2013-03-01

Full Text Available Objectives To describe HIV children's small intestinal ultrastructural findings. Methods Descriptive, observational study of small intestine biopsies performed between August 1994 and May 1995 at São Paulo, SP, Brazil. This material pertained to 11 HIV infected children and was stored in a laboratory in paraffin blocks. Scanning and transmission electronic microscopy were used to view those intestine samples and ultrastructural findings were described by analyzing digitalized photos of this material. Ethical Committee approval was obtained. Results In most samples scanning microscopy showed various degrees of shortening and decreasing number of microvilli and also completes effacements in some areas. Derangement of the enterocytes was seen frequently and sometimes cells well defined borders limits seemed to be loosened. In some areas a mucous-fibrin like membrane with variable thickness and extension appeared to partially or totally coat the epithelial surface. Fat drops were present in the intestinal lumen in various samples and a bacterium morphologically resembling bacilli was seen in two occasions. Scanning microscopy confirmed transmission microscopy microvilli findings and also showed little “tufts” of those structures. In addition, it showed an increased number of vacuoles and multivesicular bodies inside various enterocytes, an increased presence of intraepithelial lymphocytes, mitochondrial vacuolization and basement membrane enlargement in the majority of samples analyzed. However, some samples exhibited normal aspect. Conclusions Our study showed the common occurrence of various important intestinal ultrastructural alterations with variable degrees among HIV infected children, some of them in our knowledge not described before.

Ultrastructure and autoradiography of dormant and activated parenchyma of Helianthus tuberosus

International Nuclear Information System (INIS)

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

1984-01-01

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

Ultrastructure and autoradiography of dormant and activated parenchyma of Helianthus tuberosus

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

1984-01-01

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

Correlation between left ventricular diastolic function before and after valve replacement surgery and myocardial ultrastructural changes in patients with left ventricular volume-overloaded valvular heart diseases

International Nuclear Information System (INIS)

Okada, Tomiro

1993-01-01

Left ventricular (LV) diastolic functions in 23 patients with aortic regurgitation (AR) and 22 patients with mitral regurgitation (MR) were evaluated by gated blood pool scintigraphy. LV myocardial biopsy was performed during open heart surgery, and LV myocardial ultrastructural changes were evaluated by electron microscope. Correlation between LV diastolic function and myocardial ultrastructural changes was examined. It was suggested that preoperative LV diastolic dysfunction occurred earlier than LV systolic dysfunction in patients with AR and MR. LV early diastolic dysfunction was especially significant in patients with AR. LV systolic function was significantly improved postoperatively compared with LV diastolic function in patients with AR and MR. It was suggested that LV interstitial fibrosis caused LV diastolic dysfunction in patients with AR and MR, and insufficiency of myocardial thickening as compensation in patients with MR. It was presumed that LV diastolic dysfunction was irreversible in patients with AR and MR in the distant postoperative period due to persistence of the preoperative myocardial ultrastructural change, e.g., interstitial fibrosis. These LV diastolic indices measured by gated pool scintigraphy were useful in predicting LV ultrastructural changes and postoperative LV dysfunction in patients with LV volume-overloaded valvular heart disease. (author)

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

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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.

Distribution and ultrastructure of interstitial cells of Cajal in the mouse colon, using antibodies to Kit and Kit(W-lacZ) mice

DEFF Research Database (Denmark)

Vanderwinden, J M; Rumessen, J J; Bernex, F

2000-01-01

kinase receptor Kit as a marker. Sections and whole mounts were studied by confocal microscopy after double immunofluorescence with specific antibodies. The ultrastructure of Kit-expressing cells was examined by electron microcopy in KitW-lacz/+ transgenic mice, which carry the lacz gene inserted...

The absence of correlations between a clinical classification and ultrastructural findings in amelogenesis imperfecta

International Nuclear Information System (INIS)

Baeckman, B.; Lundgren, T.; Engstroem, E.U.; Falk, L.K.L.; Chabala, J.M.; Levi-Setti, R.; Noren, J.G.

1993-01-01

This study was performed to examine whether a clinical classification of different phenotypes of amelogenesis imperfecta could be discernible at the ultrastructural level. 17 primary teeth from 16 children with hypomineralization, hypomaturation, or hypoplastic variants of the disease were collected for histologic studies of the enamel by means of polarized light microscopy, scanning electron microscopy (SEM), and secondary ion mass spectrometry (SIMS). Polarization microscopy showed that the enamel was hypomineralized; in 6 teeth a wavy configuration of the enamel prisms also appeared. Three histomorphologic main types could be discerned. In 10 of the teeth extensive hypermineralization of the bulk of the enamel was found. 1 tooth had an unusually tick enamel with only a thin normally mineralized surface layer. SIMS images showed less pronounced signals from Ca 2+ and Na + , but with stronger signals from Cl - and CN - , representing the organic component of enamel. The SEM images showed an irregular prism pattern with marked interprismatic areas. Irrespective of the clinical appearance or the herediatary pattern the main findings were hypomineralized enamel with or without wavy bands. Neither of the analytical methods used in this paper distinguishes between the clinical phenotypes of amelogenesis imperfecta. 35 refs., 9 figs., 1 tab

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

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

2007-06-01

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

Ultrastructural changes in the flight muscle mitochondria of adult male mosquito Culex Pipiens L I

International Nuclear Information System (INIS)

Abd Elmeguid, A.; Elmoursy, A.A.; Rouchdy, H.; Elzahraa, F.

1995-01-01

Ultrastructural differences between differentiating myoblasts of 1-day old pupae and 2-day old pupae and between well developed flight muscles in newly emerged 1-day old and 2-day old and ageing 21-day old adult male Culex Pipiens were studied. Ageing mosquitoes showed various signs of deterioration, vocalization, fusion and disorientation of cristae. 6 figs

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

DEFF Research Database (Denmark)

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

2003-01-01

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

[Lattice degeneration of the peripheral retina: ultrastructural study].

Science.gov (United States)

Bec, P; Malecaze, F; Arne, J L; Mathis, A

1985-01-01

The ultrastructural study of a case of snail track degeneration shows the presence of lipid inclusions in both the glial and the macrophage cells in every layer of the retina, and the existence of intraretinal fibers different from collagen fibers appearing to be glial filaments similar to those found in astrocytic gliomes and to the Rosenthal fibers observed in senile nervous cells. Other features were thinning of the retina and absence of blood vessels in the retina. There are no abnormalities of the vitreo-retinal juncture. All the lesions are in agreement with those observed by Daicker [Ophthalmologica, Basel 165: 360-365, 1972; Klin. Mbl. Augenheilk. 172: 581-583, 1978] with some differences, however. They are different from those found in lattice degeneration. They show that snail track degeneration is a specific form of peripheral retinal degeneration which is quite different from lattice degeneration and must not be considered similar.

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

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Evelyn Rabelo Andrade

2011-01-01

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

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

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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.

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

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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

Nanoscopic and Photonic Ultrastructural Characterization of Two Distinct Insulin Amyloid States

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Mikael Lindgren

2012-02-01

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

Ultrastructure and mitochondrial numbers in pre- and postpubertal pig oocytes

DEFF Research Database (Denmark)

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

2016-01-01

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

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

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Viera Almášiová

2014-01-01

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

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

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Shengli Ma

2015-01-01

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

Ultrastructure, biology, and phylogenetic relationships of kinorhyncha.

Science.gov (United States)

Neuhaus, Birger; Higgins, Robert P

2002-07-01

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

Ultrastructure of cells of Ulmus americana cultured in vitro and exposed to the culture filtrate of Ceratocystis ulmi

Science.gov (United States)

Paula M. Pijut; R. Daniel Lineberger; Subhash C. Domir; Jann M. Ichida; Charles R. Krause

1990-01-01

Calli of American elm susceptible and resistant to Dutch elm disease were exposed to a culture filtrate of a pathogenic isolate of Ceratocystis ulmi. Cells from untreated tissue exhibited typical internal composition associated with healthy, actively growing cells. All cells exposed to culture filtrate showed appreciable ultrastructural changes....

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

Science.gov (United States)

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

2011-12-21

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

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

Science.gov (United States)

Mahmoud, Yomna I

2015-09-01

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

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

Science.gov (United States)

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

2017-09-15

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

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

Science.gov (United States)

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

2003-06-01

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

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

Science.gov (United States)

Zechmann, Bernd; Müller, Maria; Zellnig, Günther

2005-08-01

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

Effects of soft x-ray irradiation on cell ultrastructure

International Nuclear Information System (INIS)

Ford, T.W.; Page, A.M.; Stead, A.D.; Foster, G.F.

1993-01-01

The future of X-ray microscopy lies mainly in its potential for imaging fresh, hydrated biological material at a resolution superior to that of light microscopy. For the image to be accepted as representing the cellular organization of the living cell, it is essential that artifacts are not introduced as a result of the image collection system. One possible source of artifacts is cellular damage resulting from the irradiation of the material with soft X-rays. Cells of the unicellular alga Chlorella have been examined by transmission electron microscopy (TEM) following exposure to different doses of monochromatic (380eV) soft X-rays. Extreme ultrastructural damage has been detected following doses of 10 3 -10 4 Gy, in particular loss of cellular membranes such as the internal thylakoid membranes of the chloroplast. This is discussed in relation to dosage commonly used for imaging by soft X-ray microscopy

The absence of correlations between a clinical classification and ultrastructural findings in amelogenesis imperfecta

Energy Technology Data Exchange (ETDEWEB)

Baeckman, B.; Lundgren, T.; Engstroem, E.U.; Falk, L.K.L.; Chabala, J.M.; Levi-Setti, R.; Noren, J.G. (Dept. of Pedodontics, Univ. of Goeteborg (Sweden))

1993-01-01

This study was performed to examine whether a clinical classification of different phenotypes of amelogenesis imperfecta could be discernible at the ultrastructural level. 17 primary teeth from 16 children with hypomineralization, hypomaturation, or hypoplastic variants of the disease were collected for histologic studies of the enamel by means of polarized light microscopy, scanning electron microscopy (SEM), and secondary ion mass spectrometry (SIMS). Polarization microscopy showed that the enamel was hypomineralized; in 6 teeth a wavy configuration of the enamel prisms also appeared. Three histomorphologic main types could be discerned. In 10 of the teeth extensive hypermineralization of the bulk of the enamel was found. 1 tooth had an unusually tick enamel with only a thin normally mineralized surface layer. SIMS images showed less pronounced signals from Ca[sup 2+] and Na[sup +], but with stronger signals from Cl[sup -] and CN[sup -], representing the organic component of enamel. The SEM images showed an irregular prism pattern with marked interprismatic areas. Irrespective of the clinical appearance or the herediatary pattern the main findings were hypomineralized enamel with or without wavy bands. Neither of the analytical methods used in this paper distinguishes between the clinical phenotypes of amelogenesis imperfecta. 35 refs., 9 figs., 1 tab.

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

Science.gov (United States)

Ekici, Nuran; Dane, Feruzan; Olgun, Göksel

2009-03-01

The aim of this study is to give information on ultrastructure of in vivo pollen tubes of Mimulus aurantiacus which were collected from the Botanical Garden of the University of California at Berkeley. Materials were prepared according to electron microscopy methods and examined under Zeiss electron microscope. Four zones were examined in the pollen tubes of Mimulus aurantiacus. Apical zone: Mitochondria, smooth endoplasmic reticulum, rough endoplasmic reticulum, dictyosomes and secretory vesicles were observed. Subapical zone: This area contained abundant rough endoplasmic reticulum and occasionally some smooth endoplasmic reticulum. The polysomes, mitochondria, proplastids that contain starch, small vacuoles and a few lipid bodies were detected. Nuclear zone: Both generative and vegetative cell nuclei lie in this zone. The vegetative cell nucleus was large and long. Rough endoplasmic reticulum, mitochondria, ribosomes, dictyosomes, and amyloplasts that are rich of starch were observed. Vacuolation and plug formation zone: Cytoplasm of the tubes was full of large vacuoles. Few organelles such as mitochondria, dictyosome and rough endoplasmic reticulum were detected along their periphery.

Ultrastructural identification of Ehrlich ia sp in an experimentally infected dog in Venezuela

International Nuclear Information System (INIS)

Gutierrez, N.; Martinez, M.; Arraga Alvarado, C.; Bretana, A.; Pacheco, I.; Comach, G.

1999-01-01

This study is the first report made in Venezuela concerning the ultrastructural characteristics of Ehrlich ia sp in mononuclear blood cells from an experimentally infected dog. The animal developed clinical manifestations characteristic of the infection, and typical intracytoplasmic inclusion bodies were clearly seen in blood smears stained with modified Giemsa examined by light microscopy. Microorganisms were visualized by transmission electron microscopy. The cytoplasmic inclusions, consisted of membrane-lined vacuole-containing elementary bodies. The organisms were extremely pleomorphic. Elementary bodies were surrounded by two distinct membranes and each was constituted by electro-dense granules. These findings corresponded to the described electron microscopy morphology which characterizes the Ehrlich ia genus

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

Science.gov (United States)

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

2016-06-01

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

The Ultrastructure Of Pollinia Of Ten Species Of Orchid In Substribe Aeridinae (ORCHIDACEAE)

International Nuclear Information System (INIS)

Sulistyono; Purbaningsih, Susiani; Pujoarianto, Agus

2000-01-01

Orchid taxonimy lags several decades behind the taxonomy of most other large interisting groups of plants. New methods and techiniques, like scanning and transmission electron microscope are rarely applied in orchid's taxonomy. It would be most benefical to orchid taxonomy if a better understanding of the pollinia could be obtained. The main purpose of this research is to study the ultrastructure pollinia of ten species of Aeridinae (Orchidaceae). The scanning electron microscope (SEM) has been used to study the pollinia of ten species of orchids in the substribe Aeridina. This work shows that the ultrastructure of the pollinias are different. Regarding at the number and the surface of pollinia in one flowe, the ten species of Aeridinae can be devided mto three main group: (1) the first group is the flowe with two pollinia with it surface porate : Ascocentrum miniatum; (2) the second group has the same number of pollinia, but with surface cleft : Phalaenopsis. Ph. amboinensis, Ph.cornu-cervi, Ph. Fuscata, Ph. Venosa, Rhychostylis retusa, Vanda limbota, and Vanda insignis: and the third (3)is the flower with four pollinia, unequel : Kingidium deliciosum

Ultrastructural and metabolic changes in osteoblasts exposed to uranyl nitrate

International Nuclear Information System (INIS)

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

2007-01-01

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

Ultrastructure changes in the haemocytes of Galleria mellonella larvae treated with gamma irradiated Steinernema carpocapsae BA2

Directory of Open Access Journals (Sweden)

Hedayat-allah M. Salem

2014-01-01

Full Text Available The ultrastructure studies on the haemolymph of 5th larval instar of Galleria mellonella showed five types of haemocytes; Prohaemocytes, Plasmatocytes, Granulocytes, Oenocytoids and Spherulocytes. After treatment with Steinernema carpocapsae BA2, the haemocytes underwent considerable structural changes. More destructive effects were observed in the haemocytes of G. mellonella treated with gamma irradiated S. carpocapsae.

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

Science.gov (United States)

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

2010-11-01

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

The effect of AgNO3 on the bioenergetic processes and the ultrastructure of Chlorella and Dunaliella cells exposed to different saline conditions

International Nuclear Information System (INIS)

Loseva, N.L.; Alyabyev, A.Ju.; Gordon, L.Kh.; Andreyeva, I.N.; Kolesnikov, O.P.; Ponomareva, A.A.; Kemp, R.B.

2007-01-01

The effect of AgNO 3 , an inhibitor of the H + pump in the plasma membrane, on the bioenergetic processes and on the ultrastructure of the microalgae Chlorella vulgaris (salt sensitive) and Dunaliella maritima (salt resistant) was examined under varying salt concentrations. Differences between them were observed in changes of the cellular energy metabolism depending on their salt sensitivity and the inhibition of the H + pump activity. A decrease was observed in the rates of heat production (about 45%), O 2 uptake (greater than 40-50% of the control) and particularly photosynthesis (more than 80%) in Chlorella cells under the simultaneous action of NaCl and AgNO 3 . Dunaliella cells showed small to moderate rate increases for heat production (less than 7%), O 2 uptake (10-15%) and O 2 evolution (40%) in higher salt concentrations and under the action of AgNO 3 . The production of active oxygen species was studied as an early unspecific response of microalgal cells to possible unfavorable conditions, including salt stress. The amount of superoxide formed by the Dunaliella cells was higher than that by the Chlorella cells. However, Ag + ions increased the generation rate of superoxide radicals considerably in both Chlorella and Dunaliella cells. The electron microscopy showed that changes of the algal ultrastructure of cells exposed to the action of Ag + ions were connected with the observed physiological changes and to a large extent with the alteration of the bioenergetic processes in them

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

Czech Academy of Sciences Publication Activity Database

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

2014-01-01

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

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

Science.gov (United States)

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

2010-03-01

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

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

Science.gov (United States)

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

2014-10-01

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

Identification and ultrastructural imaging of photodynamic therapy-induced microfilaments by atomic force microscopy

International Nuclear Information System (INIS)

Jung, Se-Hui; Park, Jin-Young; Yoo, Je-Ok; Shin, Incheol; Kim, Young-Myeong; Ha, Kwon-Soo

2009-01-01

Atomic force microscopy (AFM) is an emerging technique for imaging biological samples at subnanometer resolution; however, the method is not widely used for cell imaging because it is limited to analysis of surface topology. In this study, we demonstrate identification and ultrastructural imaging of microfilaments using new approaches based on AFM. Photodynamic therapy (PDT) with a new chlorin-based photosensitizer DH-II-24 induced cell shrinkage, membrane blebbing, and reorganization of cytoskeletons in bladder cancer J82 cells. We investigated cytoskeletal changes using confocal microscopy and atomic force microscopy. Extracellular filaments formed by PDT were analyzed with a tandem imaging approach based on confocal microscopy and atomic force microscopy. Ultrathin filaments that were not visible by confocal microscopy were identified as microfilaments by on-stage labeling/imaging using atomic force microscopy. Furthermore, ultrastructural imaging revealed that these microfilaments had a stranded helical structure. Thus, these new approaches were useful for ultrastructural imaging of microfilaments at the molecular level, and, moreover, they may help to overcome the current limitations of fluorescence-based microscopy and atomic force microscopy in cell imaging.

Ultrastructure of interstitial cells in subserosa of human colon

DEFF Research Database (Denmark)

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

2013-01-01

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

Ultrastructural Histopathology of Vervet Monkey Colonic Epithelium After In Vitro Exposure to Cell-free Supernatants of Shigella Cultures

OpenAIRE

Hill, R. R.; Collins, N. E.; Cowley, H. M.

2011-01-01

The full dysentery syndrome of human shigellosis is often preceded by a transient diarrhoea that may be induced by bacterial extracellular products before invasion of the colonic mucosa and development of subsequent pathology. To examine this hypothesis, we studied the effects of cell-free cultures of Shigella sp. on the ultrastructure of monkey colonic epithelium in vitro. Clinical isolates of shigella strains were grown in a niche-simulating medium. Sheets of colon wall collected from verve...

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

Science.gov (United States)

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

2014-11-01

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

[Ultrastructural features of the epidermis in turbellaria from the Lake Baikal Geocentrophora wagini (Lecithoepitheliata, Plathelminthes)].

Science.gov (United States)

Drobysheva, I M; Timoshkin, O A

2006-01-01

The epidermis of Geocentrophora wagini was studied using transmission electron microscopy. The turbellarian body was entirely covered by cilia, whose density was higher on the ventral surface compared with the dorsal one. In all regions examined, the epidermis was made up of a one-layered insunk epithelium. The basal matrix, underlying the epidermis, was a well developed basement membrane (BM) with bilayered structure, overlying the muscle network of circular and longitudinal fibers. The double plasma membranes, extending from the apical surface of epidermis to BM, were linked by specialized cell junctions. This suggested that epidermis had a cellular rather than a cyncytial arrangement. Each insunk epidermal cell was made of two unequal parts: a comparatively thin surface plate attached to BM by hemiadherens junctions, and a massive nucleated portion located below the body wall musculature in the parenchyma. A thin cytoplasmic bridge connected the epidermal plate with the nucleated cell body. The epidermal plates were joined by belt-like junctions along their adjacent surfaces. Inconspicuous zonula adherens (ZA) had a most apical position, and prominent septate junction was arrayed proximally to this zonula. Except ZA, cell boundaries in epidermis were frequently flanked by rows of light tubules and vesicles. In the basal half of the epithelial sheet, they were occassionally accompanied by single cisternae of rough endoplasmic reticulum (RER). The ultrastructure of the insunk cell body and that of the surface plate showed a considerable similarity. The common features were distinctive profiles of RER and GA, the presence of epitheliosomes, light tubules and vesicles, centrioles and fibrous granules. Thus, ultrastructural features allow a rather reliable identification of epidermal cells in the parenchyma, despite the absence of any visible morphological association between cell body and its epidermal plate.

Ultrastructural changes in human skin after exposure to a pulsed laser

Energy Technology Data Exchange (ETDEWEB)

Nakagawa, H.; Tan, O.T.; Parrish, J.A.

1985-05-01

Selective vascular injury following irradiation using a pulsed laser source at 577 nm was examined using ultrastructural methods in the skin of 3 fair-skinned healthy human volunteers. This vascular-specific damage was confined to the papillary dermis. Red blood cells were altered in several ways. As well as an increase in the electron density, configurational distortion modified the normal biconcave forms to ameboid structures. The most interesting finding was the appearance within these altered cells of well-defined circular/oval electron-lucent areas of 800 A diameter, possibly representing a heat-fixed record of steam formation within the red blood cell. In addition, considerable degenerative changes were evident in endothelial cells and pericytes, while mast cells, neutrophils, histiocytes, and fibroblasts as well as collagen bundles immediately surrounding most laser-damaged blood vessels appeared normal.

Enteric neurons show a primary cilium.

Science.gov (United States)

Luesma, Ma José; Cantarero, Irene; Castiella, Tomás; Soriano, Mario; Garcia-Verdugo, José Manuel; Junquera, Concepción

2013-01-01

The primary cilium is a non-motile cilium whose structure is 9+0. It is involved in co-ordinating cellular signal transduction pathways, developmental processes and tissue homeostasis. Defects in the structure or function of the primary cilium underlie numerous human diseases, collectively termed ciliopathies. The presence of single cilia in the central nervous system (CNS) is well documented, including some choroid plexus cells, neural stem cells, neurons and astrocytes, but the presence of primary cilia in differentiated neurons of the enteric nervous system (ENS) has not yet been described in mammals to the best of our knowledge. The enteric nervous system closely resembles the central nervous system. In fact, the ultrastructure of the ENS is more similar to the CNS ultrastructure than to the rest of the peripheral nervous system. This research work describes for the first time the ultrastructural characteristics of the single cilium in neurons of rat duodenum myenteric plexus, and reviews the cilium function in the CNS to propose the possible role of cilia in the ENS cells. © 2012 The Authors. Published by Foundation for Cellular and Molecular Medicine/Blackwell Publishing Ltd. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

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

Directory of Open Access Journals (Sweden)

Sukontason Kabkaew L

2002-01-01

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

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

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Muhammad Shahid

2017-07-01

Full Text Available 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

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

Science.gov (United States)

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.

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

DEFF Research Database (Denmark)

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

2011-01-01

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

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

International Nuclear Information System (INIS)

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

1988-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

Abdrakhmanov, A A

1988-06-01

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

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

Science.gov (United States)

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

2012-07-01

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

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

Science.gov (United States)

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

2012-01-01

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

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

International Nuclear Information System (INIS)

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

2008-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2008-03-15

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

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

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Horstmann, Heinz; Körber, Christoph; Sätzler, Kurt; Aydin, Daniel; Kuner, Thomas

2012-01-01

High resolution, three-dimensional (3D) representations of cellular ultrastructure are essential for structure function studies in all areas of cell biology. While limited subcellular volumes have been routinely examined using serial section transmission electron microscopy (ssTEM), complete ultrastructural reconstructions of large volumes, entire cells or even tissue are difficult to achieve using ssTEM. Here, we introduce a novel approach combining serial sectioning of tissue with scanning electron microscopy (SEM) using a conductive silicon wafer as a support. Ribbons containing hundreds of 35 nm thick sections can be generated and imaged on the wafer at a lateral pixel resolution of 3.7 nm by recording the backscattered electrons with the in-lens detector of the SEM. The resulting electron micrographs are qualitatively comparable to those obtained by conventional TEM. S(3)EM images of the same region of interest in consecutive sections can be used for 3D reconstructions of large structures. We demonstrate the potential of this approach by reconstructing a 31.7 µm(3) volume of a calyx of Held presynaptic terminal. The approach introduced here, Serial Section SEM (S(3)EM), for the first time provides the possibility to obtain 3D ultrastructure of large volumes with high resolution and to selectively and repetitively home in on structures of interest. S(3)EM accelerates process duration, is amenable to full automation and can be implemented with standard instrumentation.

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

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Heinz Horstmann

Full Text Available High resolution, three-dimensional (3D representations of cellular ultrastructure are essential for structure function studies in all areas of cell biology. While limited subcellular volumes have been routinely examined using serial section transmission electron microscopy (ssTEM, complete ultrastructural reconstructions of large volumes, entire cells or even tissue are difficult to achieve using ssTEM. Here, we introduce a novel approach combining serial sectioning of tissue with scanning electron microscopy (SEM using a conductive silicon wafer as a support. Ribbons containing hundreds of 35 nm thick sections can be generated and imaged on the wafer at a lateral pixel resolution of 3.7 nm by recording the backscattered electrons with the in-lens detector of the SEM. The resulting electron micrographs are qualitatively comparable to those obtained by conventional TEM. S(3EM images of the same region of interest in consecutive sections can be used for 3D reconstructions of large structures. We demonstrate the potential of this approach by reconstructing a 31.7 µm(3 volume of a calyx of Held presynaptic terminal. The approach introduced here, Serial Section SEM (S(3EM, for the first time provides the possibility to obtain 3D ultrastructure of large volumes with high resolution and to selectively and repetitively home in on structures of interest. S(3EM accelerates process duration, is amenable to full automation and can be implemented with standard instrumentation.

Oncocytic carcinoma of parotid gland: a case report with clinical, immunohistochemical and ultrastructural features

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Giordano Giovanna

2006-08-01

Full Text Available Abstract Background Oncocytic carcinoma is an extremely rare neoplasm of the salivary glands. We report a case of oncocytic carcinoma arising in a parotid gland in a 66-year-old female. Method An excisional biopsy of the parotid tumor was performed. The specimen was submitted for histology and after fixation in formalin solution and inclusion in paraffin, 3–5 μm sections were stained with hematoxylin and eosin for conventional evaluation and Periodic acid Schiff stain. Immunohistochemical studies were performed using antibodies against mitochondrial antigen, keratin, S-100, alpha-actin, vimentin, alpha-1-antichymotrypsin as well as an ultrastructural analysis was performed. Results Frozen sections revealed an infiltrative growth pattern and the diagnosis of a malignant epithelial lesion was made. Permanent sections stained with haematoxylin and eosin revealed a neoplasm that had replaced a wide area of the parotid gland and had invaded subcutaneous adipose tissue. Perineural invasion was evident, but vascular invasion was not found. Neoplastic elements were large, round or polyhedral cells and were arranged in solid sheets, islands and cords. The cytoplasm was abundant, eosinophilic and finely granular. The nuclei were large and located centrally or peripherally. The nucleoli were distinct and large. Periodic acid Schiff stain demonstrated a granular cytoplasm. Immunohistochemistry demonstrated mithochondrial antigen, keratin, and chymotrypsin immunoreactivity in the neoplastic cells. Ultrastructural analysis revealed numerous mitochondria packed into the cytoplasm of the neoplastic cells. Thus, the final diagnosis was that of oncocytic carcinoma of parotid gland. Conclusion This neoplasm shows clinical, microscopical, histological and ultrastructural features of oncocytic carcinoma and this must be considered in the differential diagnosis of other proliferations in the parotid gland with abundant granular cytoplasm and metastatic oncocytic

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

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

2016-08-01

A field experiment was conducted to study the effects of shading on the photosynthetic characteristics and mesophyll cell ultrastructure of two summer maize hybrids Denghai605 (DH605) and Zhengdan958 (ZD958). The ambient sunlight treatment was used as control (CK) and shading treatments (40 % of ambient sunlight) were applied at different growth stages from silking (R1) to physiological maturity (R6) (S1), from the sixth leaf stage (V6) to R1 (S2), and from seeding to R6 (S3), respectively. The net photosynthetic rate (P n) was significantly decreased after shading. The greatest reduction of P n was found at S3 treatment, followed by S1 and S2 treatments. P n of S3 was decreased by 59 and 48 % for DH605, and 39 and 43 % for ZD958 at tasseling and milk-ripe stages, respectively, compared to that of CK. Additionally, leaf area index (LAI) and chlorophyll content decreased after shading. In terms of mesophyll cell ultrastructure, chloroplast configuration of mesophyll cells dispersed, and part of chloroplast swelled and became circular. Meanwhile, the major characteristics of chloroplasts showed poorly developed thylakoid structure at the early growth stage, blurry lamellar structure, loose grana, and a large gap between slices and warping granum. Then, plasmolysis occurred in mesophyll cells and the endomembrane system was destroyed, which resulted in the dissolution of cell membrane, karyotheca, mitochondria, and some membrane structures. The damaged mesophyll cell ultrastructure led to the decrease of photosynthetic capacity, and thus resulted in significant yield reduction by 45, 11, and 84 % in S1, S2, and S3 treatments, respectively, compared to that of CK.

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

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

2006-01-01

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

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

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Bakhoum Abdoulaye Jacque

2014-01-01

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

[Ultrastructural study on the nucleus pulposus of the inter-vertebral disc--the behavior of the cells in the nucleus pulposus and their autolytic changes in the monkey].

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Hase, H

1985-08-01

Ultrastructural studies were carried out to examine the normal structure and postmortem autolytic changes of the cells and matrix of nucleus pulposus using adult monkey. Two kinds of cells were observed in the nucleus pulposus. The one was chondrocyte, which contained normal organelles and that was characterized by large halo. The halo was composed of numerous "crista like structures", that were regarded to form the matrix of nucleus pulposus. The other was notochordal cell, most of which appeared in grouping or separately, and yet had cell activity. In addition, there were the intermediate type of cells between chondrocyte and notochordal cell. The ultrastructural autolytic changes were rarely seen in the cells of 6 hours after death, but the changes in the halo and in the cytoplasm were remarkable after more than 12 hours. The autopsied nucleus pulposus for electron microscopical examination should be used within 6 hours after death in usual room temperature.

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

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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.

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

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

2015-01-01

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

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

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Manal Abdul-Hamid

2017-06-01

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

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

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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.

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

African Journals Online (AJOL)

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

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

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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

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

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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

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.

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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.

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

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Bojie Hu

2014-01-01

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

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

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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.

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

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

2004-06-01

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

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

Science.gov (United States)

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

2004-06-01

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

Cadmium-induced functional and ultrastructural alterations in roots of two transgenic cotton cultivars

International Nuclear Information System (INIS)

Daud, M.K.; Sun, Yuqiang; Dawood, M.; Hayat, Y.; Variath, M.T.; Wu Yuxiang; Raziuddin; Mishkat, Ullah; Salahuddin; Najeeb, Ullah; Zhu, Shuijin

2009-01-01

The toxic effect of cadmium (Cd) at increasing concentrations was studied with special attention being given to the root morphological and ultrastructural changes in two transgenic cotton cultivars viz. BR001 and GK30 and their wild relative viz. Coker 312. In comparison to their respective controls, low concentration (10 and 100 μM) of Cd greatly stimulated seed germination, while it was inhibited by highest concentration of Cd (1000 μM) in case of two transgenic cultivars. However, in Coker 312 the seed germination percentage progressively decreased over the control at all Cd levels. Various physiological and morphological parameters of the root and whole plant in both transgenic cotton cultivars and their relative wild cotton genotype respond differently towards the Cd toxicity. Bioavailability of Cd was concentration-dependent where seedling root captured more Cd as compared to shoot. BR001 accumulated more Cd followed by GK30, while Coker 312 was less Cd accumulator. The ultrastructural modifications in the root tip cells of both the transgenic cotton cultivars and their wild relative were also dose-dependent. With the increase in Cd levels, the fine structures of their root cells also invariably changed. Increase in plasmolysis of the plasma membrane, greater number of nucleoli and vacuoles and enlarged vacuoles could be observed in both transgenic cotton cultivars. In comparison to them, Coker 312 showed relatively well developed ultrastructures of the root tips except enlarged vacuoles and greater number of mitochondria. Moreover, the accumulation of Cd in the form of electron dense granules and crystals both in vacuoles and attached to cell walls were visible in both transgenic cotton cultivars and their wild relative. These results suggest that both transgenic cotton cultivars and their wild relative cotton genotype responded positively towards Cd stress at seedling stage, the internal Cd-detoxification might be through apoplastic and symplastic binding

Cadmium-induced functional and ultrastructural alterations in roots of two transgenic cotton cultivars

Energy Technology Data Exchange (ETDEWEB)

Daud, M.K.; Sun, Yuqiang; Dawood, M. [Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China); Hayat, Y. [Institute of Bioinformatics, Zhejiang University, Hangzhou 310029 (China); Variath, M.T.; Wu Yuxiang [Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China); Raziuddin [Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China); Plant Breeding and Genetics Department, NWFP Agricultural University Peshawar, Peshawar (Pakistan); Mishkat, Ullah [Zoological Sciences Division, Pakistan Museum of Natural History, Garden Avenue, Shakarparian, Islamabad 44000 (Pakistan); Salahuddin [District Agriculture Extension Offices, Bannu Road, Dera Ismail Khan (NWFP) (Pakistan); Najeeb, Ullah [Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China); Zhu, Shuijin [Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China)], E-mail: shjzhu@zju.edu.cn

2009-01-15

The toxic effect of cadmium (Cd) at increasing concentrations was studied with special attention being given to the root morphological and ultrastructural changes in two transgenic cotton cultivars viz. BR001 and GK30 and their wild relative viz. Coker 312. In comparison to their respective controls, low concentration (10 and 100 {mu}M) of Cd greatly stimulated seed germination, while it was inhibited by highest concentration of Cd (1000 {mu}M) in case of two transgenic cultivars. However, in Coker 312 the seed germination percentage progressively decreased over the control at all Cd levels. Various physiological and morphological parameters of the root and whole plant in both transgenic cotton cultivars and their relative wild cotton genotype respond differently towards the Cd toxicity. Bioavailability of Cd was concentration-dependent where seedling root captured more Cd as compared to shoot. BR001 accumulated more Cd followed by GK30, while Coker 312 was less Cd accumulator. The ultrastructural modifications in the root tip cells of both the transgenic cotton cultivars and their wild relative were also dose-dependent. With the increase in Cd levels, the fine structures of their root cells also invariably changed. Increase in plasmolysis of the plasma membrane, greater number of nucleoli and vacuoles and enlarged vacuoles could be observed in both transgenic cotton cultivars. In comparison to them, Coker 312 showed relatively well developed ultrastructures of the root tips except enlarged vacuoles and greater number of mitochondria. Moreover, the accumulation of Cd in the form of electron dense granules and crystals both in vacuoles and attached to cell walls were visible in both transgenic cotton cultivars and their wild relative. These results suggest that both transgenic cotton cultivars and their wild relative cotton genotype responded positively towards Cd stress at seedling stage, the internal Cd-detoxification might be through apoplastic and symplastic

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

Science.gov (United States)

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

2004-06-01

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

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

Science.gov (United States)

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 = 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.

Ultrastructural muscle and neuro-muscular junction alterations in polymyositis

Directory of Open Access Journals (Sweden)

L. L. Babakova

2012-01-01

Full Text Available Ultrastructural analysis of 7 biopsies from m.palmaris longus and m.deltoideus in patients with confirmed polymyositis revealed alterationand degeneration of muscle fibers and anomalies of neuro-muscular junction (NMJ. The NMJ abnormalities and following denervation ofmuscle fibers in polymyositis start with subsynaptic damages. The occurance of regeneration features in muscle fibers at any stage is characteristic for PM.

The effect of AgNO{sub 3} on the bioenergetic processes and the ultrastructure of Chlorella and Dunaliella cells exposed to different saline conditions

Energy Technology Data Exchange (ETDEWEB)

Loseva, N.L. [Institute of Biochemistry and Biophysics, Russian Academy of Sciences, P.O. Box 30, Kazan 420111 (Russian Federation)]. E-mail: loseva@mail.knc.ru; Alyabyev, A.Ju. [Institute of Biochemistry and Biophysics, Russian Academy of Sciences, P.O. Box 30, Kazan 420111 (Russian Federation); Gordon, L.Kh. [Institute of Biochemistry and Biophysics, Russian Academy of Sciences, P.O. Box 30, Kazan 420111 (Russian Federation); Andreyeva, I.N. [Institute of Biochemistry and Biophysics, Russian Academy of Sciences, P.O. Box 30, Kazan 420111 (Russian Federation); Kolesnikov, O.P. [Institute of Biochemistry and Biophysics, Russian Academy of Sciences, P.O. Box 30, Kazan 420111 (Russian Federation); Ponomareva, A.A. [Institute of Biochemistry and Biophysics, Russian Academy of Sciences, P.O. Box 30, Kazan 420111 (Russian Federation); Kemp, R.B. [Institute of Biological Sciences, Edward Llwyd Building, Penglais, University of Wales, Aberystwyth SY23 3DA (United Kingdom)

2007-06-25

The effect of AgNO{sub 3}, an inhibitor of the H{sup +} pump in the plasma membrane, on the bioenergetic processes and on the ultrastructure of the microalgae Chlorella vulgaris (salt sensitive) and Dunaliella maritima (salt resistant) was examined under varying salt concentrations. Differences between them were observed in changes of the cellular energy metabolism depending on their salt sensitivity and the inhibition of the H{sup +} pump activity. A decrease was observed in the rates of heat production (about 45%), O{sub 2} uptake (greater than 40-50% of the control) and particularly photosynthesis (more than 80%) in Chlorella cells under the simultaneous action of NaCl and AgNO{sub 3}. Dunaliella cells showed small to moderate rate increases for heat production (less than 7%), O{sub 2} uptake (10-15%) and O{sub 2} evolution (40%) in higher salt concentrations and under the action of AgNO{sub 3}. The production of active oxygen species was studied as an early unspecific response of microalgal cells to possible unfavorable conditions, including salt stress. The amount of superoxide formed by the Dunaliella cells was higher than that by the Chlorella cells. However, Ag{sup +} ions increased the generation rate of superoxide radicals considerably in both Chlorella and Dunaliella cells. The electron microscopy showed that changes of the algal ultrastructure of cells exposed to the action of Ag{sup +} ions were connected with the observed physiological changes and to a large extent with the alteration of the bioenergetic processes in them.

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

International Nuclear Information System (INIS)

Cilliers, G.D.; Lochner, A.

1989-01-01

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

The ultrastructural morphology of native hepatitis B virus.

Science.gov (United States)

Kaito, Masahiko; Ohba, Hiroyoshi; Chiba, Joe; Kohara, Michinori; Tanaka, Hideaki; Fujita, Naoki; Gabazza, Esteban Cesar; Watanabe, Shozo; Konishi, Masayoshi; Adachi, Yukihiko

2006-09-01

Cell lines (2.2.15 cells) capable of supporting the replication of hepatitis B virus (HBV) DNA and intact viral particles have been established by HBV DNA transfection into HepG2 cells. The purpose of this study was to determine the ultrastructural morphology of native HBV particles without purification in the culture supernatants and in sera from patients. Electron microscopy (EM) and immunogold EM of the samples were carried out using polyclonal and monoclonal anti-hepatitis B surface antigen antibodies. HBV particles in the purified samples from the culture supernatants by density-gradient centrifugation were examined to compare the morphology with that of unpurified samples. EM and immunogold EM studies demonstrated the presence of Dane particles (41.8 nm in diameter), cobra-shaped (head diameter, 42.4 nm), and horn-shaped (head diameter, 43.5 nm) particles in the culture supernatants and in the sera from two patients. The tail of the cobra-like particles had a diameter of 21.0 nm and a length of 214 nm. The hornlike particles had a long branch 20.1 nm in diameter with a length of 189 nm, and a short branch 21.4 nm in diameter with a length of 112 nm. The ratio of Dane particles and cobra- and horn-shaped particles in the supernatants was 5 : 4 : 1. After ultracentrifugation, the cobra- and horn-shaped particles completely disappeared; there were only Dane particles together with spheres of 22 nm and filaments. In conclusion, this study showed for the first time that the native replicative form of HBV is cobra- and horn-shaped.

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

DEFF Research Database (Denmark)

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

2014-01-01

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

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

Science.gov (United States)

Kornakova, E E

2012-01-01

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

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

Science.gov (United States)

Kornakova, E E

2010-01-01

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

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

Science.gov (United States)

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

1976-10-01

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

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

Directory of Open Access Journals (Sweden)

Maria Inês L. Sogayar

1989-08-01

Full Text Available 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.

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

Science.gov (United States)

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

2006-01-01

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

Ultrastructural study of the chromatoid body in planarian regenerative cells

Energy Technology Data Exchange (ETDEWEB)

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

1982-04-01

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

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

Science.gov (United States)

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

2010-02-01

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

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

Science.gov (United States)

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

1993-06-01

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

Correlation between left ventricular diastolic function before and after valve replacement surgery and myocardial ultrastructural changes in patients with left ventricular volume-overloaded valvular heart diseases; Evaluation with gated blood pool scintigraphy using [sup 99m]Tc

Energy Technology Data Exchange (ETDEWEB)

Okada, Tomiro (Okayama Univ. (Japan). School of Medicine)

1993-06-01

Left ventricular (LV) diastolic functions in 23 patients with aortic regurgitation (AR) and 22 patients with mitral regurgitation (MR) were evaluated by gated blood pool scintigraphy. LV myocardial biopsy was performed during open heart surgery, and LV myocardial ultrastructural changes were evaluated by electron microscope. Correlation between LV diastolic function and myocardial ultrastructural changes was examined. It was suggested that preoperative LV diastolic dysfunction occurred earlier than LV systolic dysfunction in patients with AR and MR. LV early diastolic dysfunction was especially significant in patients with AR. LV systolic function was significantly improved postoperatively compared with LV diastolic function in patients with AR and MR. It was suggested that LV interstitial fibrosis caused LV diastolic dysfunction in patients with AR and MR, and insufficiency of myocardial thickening as compensation in patients with MR. It was presumed that LV diastolic dysfunction was irreversible in patients with AR and MR in the distant postoperative period due to persistence of the preoperative myocardial ultrastructural change, e.g., interstitial fibrosis. These LV diastolic indices measured by gated pool scintigraphy were useful in predicting LV ultrastructural changes and postoperative LV dysfunction in patients with LV volume-overloaded valvular heart disease. (author).

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

Science.gov (United States)

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

2014-04-01

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

A new nidovirus (NamDinh virus NDiV): Its ultrastructural characterization in the C6/36 mosquito cell line

Energy Technology Data Exchange (ETDEWEB)

Thuy, Nguyen Thanh, E-mail: ngtthuy02@yahoo.com [National Institute of Hygiene and Epidemiology, 1 Yersin Street, Hai Ba Trung District, Hanoi (Viet Nam); Huy, Tran Quang, E-mail: huytq@nihe.org.vn [National Institute of Hygiene and Epidemiology, 1 Yersin Street, Hai Ba Trung District, Hanoi (Viet Nam); Nga, Phan Thi [National Institute of Hygiene and Epidemiology, 1 Yersin Street, Hai Ba Trung District, Hanoi (Viet Nam); Morita, Kouichi [Department of Virology, Institute of Tropical Medicine, Global COE Program, Nagasaki University, Nagasaki (Japan); Dunia, Irene; Benedetti, Lucio [Institut Jacques Monod, UMR7592 Université Paris Diderot/CNRS, Paris (France)

2013-09-15

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

Ultrastructural study of Rift Valley fever virus in the mouse model

Energy Technology Data Exchange (ETDEWEB)

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

2012-09-15

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

Ultrastructural study of Rift Valley fever virus in the mouse model

International Nuclear Information System (INIS)

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

2012-01-01

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

Pathology of post-kala-azar dermal leishmaniasis: a light microscopical, immunohistochemical, and ultrastructural study of skin lesions and draining lymph nodes

DEFF Research Database (Denmark)

Ismail, Ahmed; Gadir, A Fattah A; Theander, Thor G

2006-01-01

BACKGROUND: Whereas the clinical manifestations and treatment of post-kala-azar dermal leishmaniasis (PKDL) have been adequately described before, the pathology received little attention, particularly the African form of PKDL which shows some clinical differences from the disease in India...... leishmaniasis: a light microscopical, immunohistochemical, and ultrastructural study of skin lesions and draining lymph nodes....

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

Science.gov (United States)

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

2013-02-01

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

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

Science.gov (United States)

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

1975-01-01

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

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

Science.gov (United States)

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

2015-04-29

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

Ultrastructure of endothelium in ovules of Penstemon gentianoides Poir. (Scrophulariaceae) at mature embryo sac phase.

Science.gov (United States)

Dane, Feruzan; Olgun, Göksel; Ekici, Nuran

2007-06-01

In this study ultrastructural differences between endothelial cells of different location in Penstemon gentianoides have been examined with electron microscope at mature embryo sac phase. Embryo sac is of the Polygonum type and surrounded by endothelium except the micropylar region. The cuticle is located primarily around the chalazal three-fourths of the embryo sac. Endothelium cells around the chalaza and toward the micropylar region are rich in cytoplasmic organelles. The cytoplasm of endothelial cells near the central cell has large vacuoles and few organelles. There are also plasmodesmas on the anticlinal walls of endothelial cells. The endothelium and the micropylar integumentary cells play a role in transport of metabolites into the embryo sac.

Expression dynamics and ultrastructural localization of epitope-tagged Abutilon mosaic virus nuclear shuttle and movement proteins in Nicotiana benthamiana cells

International Nuclear Information System (INIS)

Kleinow, Tatjana; Tanwir, Fariha; Kocher, Cornelia; Krenz, Bjoern; Wege, Christina; Jeske, Holger

2009-01-01

The geminivirus Abutilon mosaic virus (AbMV) encodes two proteins which are essential for viral spread within plants. The nuclear shuttle protein (NSP) transfers viral DNA between the nucleus and cytoplasm, whereas the movement protein (MP) facilitates transport between cells through plasmodesmata and long-distance via phloem. An inducible overexpression system for epitope-tagged NSP and MP in plants yielded unprecedented amounts of both proteins. Western blots revealed extensive posttranslational modification and truncation for MP, but not for NSP. Ultrastructural examination of Nicotiana benthamiana tissues showed characteristic nucleopathic alterations, including fibrillar rings, when epitope-tagged NSP and MP were simultaneously expressed in leaves locally infected with an AbMV DNA A in which the coat protein gene was replaced by a green fluorescent protein encoding gene. Immunogold labelling localized NSP in the nucleoplasm and in the fibrillar rings. MP appeared at the cell periphery, probably the plasma membrane, and plasmodesmata.

Ultrastructural Changes during the Life Cycle of Mycoplasma salivarium in Oral Biopsies from Patients with Oral Leukoplakia

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Harumi Mizuki

2017-09-01

Full Text Available Bacteria in genus Mycoplasma spp. are the smallest and simplest form of freely replicating bacteria, with 16 species known to infect humans. In the mouth, M. salivarium is the most frequently identified species. Mycoplasma spp. are parasites with small genomes. Although most of the Mycoplasma spp. that infect humans remain attached to the host cell surface throughout their life cycle, we have previously reported the presence of Mycoplasma salivarium in the epithelial cells of oral leukoplakia and oral lichen planus. However, the mechanism underlying the pathogenicity of M. salivarium has remained unclear. Further studies are needed to identify the process of infection of human cells and the stages in the life cycle of M. salivarium. Electron microscopy (EM is the method of choice for morphological investigation of Mycoplasma spp. in cells or tissues. This study was performed to clarify and detail the ultrastructure of M. salivarium in tissue biopsies of oral mucosal leukoplakia, using three EM methods: (1 a standard EM processing method; (2 an ultracryotomy and immunolabeling method; and (3 the LR White resin post-embedding and immunolabeling method. This study included five oral leukoplakia tissue samples showing hyperplasia and hyperkeratosis. Although there was some variation in ultrastructural appearances between the three EM methods used, there were four ultrastructural appearances that are believed to reflect the stages of the M. salivarium life cycle in the epithelial cells of the oral mucosa: (1 small, electron-dense cellular-like structures or elementary bodies of M. salivarium; (2 large structures of M. salivarium; (3 M. salivarium organisms in cell division; (4 the sequence of events in the life cycle of M. salivarium that includes: (a elementary bodies of M. salivarium deep in the oral mucosal epithelium; (b replication by binary fission and daughter cell division from the elementary bodies; (c maturation or degeneration of M

Ultrastructural Alterations of Von Economo Neurons in the Anterior Cingulate Cortex in Schizophrenia.

Science.gov (United States)

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.

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

International Nuclear Information System (INIS)

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

2004-01-01

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

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

Czech Academy of Sciences Publication Activity Database

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

2005-01-01

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

Ultrastructural Changes in Cherimoya Fruit Injured by Chilling

OpenAIRE

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

1992-01-01

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

Microstructure and ultrastructure of alfalfa seeds with different moisture contents after satellite carrying

International Nuclear Information System (INIS)

Feng Peng; Li Jian; Zhang Yunwei; Liu Ruohan

2009-01-01

Seeds with different moisture contents (9%, 11%, 13%, 15%, 17%) of Medicago sativa L. cv. Zhongmu No. 1 were boarded on the Shijian-8 satellite and then the microscopic and ultrastructure were observed. The results showed that spongy tissue and leaf palisade of plant after space flight were different to their control. The impact of on spongy cells was more obvious than the palisade cells; greater chloroplasts, empty and crack overflow mitochondria were observed. More starch grain were found at the samples cultured from 15% and 17% moisture content treatment, which was analyzed that starch grains in leaf cell was affected by the moisture content of seeds. (authors)

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

Science.gov (United States)

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

2016-11-01

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

Molecular and Ultrastructural Mechanisms Underlying Yellow Dwarf Symptom Formation in Wheat after Infection of Barley Yellow Dwarf Virus.

Science.gov (United States)

Rong, Wei; Wang, Xindong; Wang, Xifeng; Massart, Sebastien; Zhang, Zengyan

2018-04-13

Wheat ( Tritium aestivum L.) production is essential for global food security. Infection of barley yellow dwarf virus-GAV (BYDV-GAV) results in wheat showing leaf yellowing and plant dwarfism symptom. To explore the molecular and ultrastructural mechanisms underlying yellow dwarf symptom formation in BYDV-GAV-infected wheat, we investigated the chloroplast ultrastructure via transmission electron microscopy (TEM), examined the contents of the virus, H₂O₂, and chlorophyll in Zhong8601, and studied the comparative transcriptome through microarray analyses in the susceptible wheat line Zhong8601 after virus infection. TEM images indicated that chloroplasts in BYDV-GAV-infected Zhong8601 leaf cells were fragmentized. Where thylakoids were not well developed, starch granules and plastoglobules were rare. Compared with mock-inoculated Zhong8601, chlorophyll content was markedly reduced, but the virus and H₂O₂ contents were significantly higher in BYDV-GAV-infected Zhong8601. The transcriptomic analyses revealed that chlorophyll biosynthesis and chloroplast related transcripts, encoding chlorophyll a/b binding protein, glucose-6-phosphate/phosphate translocator 2, and glutamyl-tRNA reductase 1, were down-regulated in BYDV-GAV-infected Zhong8601. Some phytohormone signaling-related transcripts, including abscisic acid (ABA) signaling factors (phospholipase D alpha 1 and calcineurin B-like protein 9) and nine ethylene response factors, were up-regulated. Additionally, reactive oxygen species (ROS)-related genes were transcriptionally regulated in BYDV-GAV infected Zhong8601, including three up-regulated transcripts encoding germin-like proteins (promoting ROS accumulation) and four down-regulated transcripts encoding peroxides (scavenging ROS). These results clearly suggest that the yellow dwarf symptom formation is mainly attributed to reduced chlorophyll content and fragmentized chloroplasts caused by down-regulation of the chlorophyll and chloroplast biosynthesis

Ultrastructure of the human preovulatory oocyte.

Science.gov (United States)

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

1986-08-01

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

Ultrastructural observations reveal the presence of channels between cork cells.

Science.gov (United States)

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.

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

Energy Technology Data Exchange (ETDEWEB)

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

1986-01-01

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

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

Science.gov (United States)

Mahmoud, Yomna Ibrahim

2012-07-01

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

Ultrastructural Analysis of Leishmania infantum chagasi Promastigotes Forms Treated In Vitro with Usnic Acid

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João S. B. da Luz

2015-01-01

Full Text Available Leishmaniasis is considered by the World Health Organization as one of the infectious parasitic diseases endemic of great relevance and a global public health problem. Pentavalent antimonials used for treatment of this disease are limited and new phytochemicals emerge as an alternative to existing treatments, due to the low toxicity and cost reduction. Usnic acid is uniquely found in lichens and is especially abundant in genera such as Alectoria, Cladonia, Evernia, Lecanora, Ramalina, and Usnea. Usnic acid has been shown to exhibit antiviral, antiprotozoal, antiproliferative, anti-inflammatory, and analgesic activity. The aim of this study was to evaluate the antileishmanial activity of usnic acid on Leishmania infantum chagasi promastigotes and the occurrence of drug-induced ultrastructural damage in the parasite. Usnic acid was effective against the promastigote forms (IC50 = 18.30 ± 2.00 µg/mL. Structural and ultrastructural aspects of parasite were analyzed. Morphological alterations were observed as blebs in cell membrane and shapes given off, increasing the number of cytoplasmic vacuoles, and cellular and mitochondrial swelling, with loss of cell polarity. We concluded that the usnic acid presented antileishmanial activity against promastigote forms of Leishmania infantum chagasi and structural and ultrastructural analysis reinforces its cytotoxicity. Further, in vitro studies are warranted to further evaluate this potential.

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

International Nuclear Information System (INIS)

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

2006-01-01

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

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

Science.gov (United States)

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

2013-04-01

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

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

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Viviane Helena Chirinéa

2009-07-01

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

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

The Ultrastructural Effects of Sulfachloropyrazine on Toxoplasma Gondii Tachyzoites

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YB Zeng

2013-03-01

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

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

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Dolores del Carmen Castro

2002-09-01

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

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

Czech Academy of Sciences Publication Activity Database

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

2009-01-01

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

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

Science.gov (United States)

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

2017-05-01

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

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

Science.gov (United States)

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

Ultrastructural evaluation of gingival connective tissue in hereditary gingival fibromatosis.

Science.gov (United States)

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

2016-07-01

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

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

Science.gov (United States)

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

2018-05-19

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

The Protective Effect of Proponyl-L-Carnitine Against Ultrastructural Alterations in Cardiac Muscle of Irradiated and / or diabetic Rats

International Nuclear Information System (INIS)

Abu Nour, S.M.; Abdel-Azeem, M.G.; El-Nashar, D.E.M.

2011-01-01

Heart dysfunction in chronic diabetes has been observed to be associated with depressed myofibrillar adenosine triphosphatase activities. Oxidative stress a factor implicated in the heart injury may contribute towards some of these alterations. The present study was designed to evaluate the efficacy of L-carnitine on gamma radiation and diabetes induced oxidative damage in the heart by investigating alterations in the ultrastructural level. Streptozotocin was intraperitoneally injected (i.p) to rats at a dose of 28 mg/Kg b.wt / day for 2 weeks pre-irradiation. In irradiated groups, animals were exposed to 6.5 Gy whole body gamma radiation. L-carnitine was intraperitoneally injected (i.p) to rats at a dose of 250 mg/Kg b.wt/day for 2 weeks pre-irradiation. Animals were sacrificed on the 7th day after irradiation. The results demonstrated that the whole body exposure of rats to ionizing radiation induce oxidative stress which showed alterations on the ultrastructural level included dis organization with mayofibrillolysis relatively intact z-band (Z), fibrosis, swollen mitochondria, apoptotic nuclei and thickened walls of capillaries. In diabetic rats cardio muscle focal loss of myofilaments, also swelling of mitochondria and rupture of sacroplasmic reticulum, apoptotic nuclei with dilation of capillaries were evident. Administration of L-carnitine pre-irradiation has improved the ultrastructural alterations of the heart tissue. It is proposed that the oxidative stress is associated with a deficit in the status of the antioxidant defense system which may play a critical role in subcellular remodeling, calcium-handling abnormalities and subsequent diabetic cardiomyopathy

Autoradiographic and ultrastructural studies on the human fibro-atheromatous plaque

Energy Technology Data Exchange (ETDEWEB)

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

1983-07-01

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

Autoradiographic and ultrastructural studies on the human fibro-atheromatous plaque

International Nuclear Information System (INIS)

Villaschi, Sergio; Spagnoli, L.G.

1983-01-01

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

Effect of X- and γ-irradiation on the ultrastructure of Haematococcus pluvialis

International Nuclear Information System (INIS)

Jiang Xiamin; Zhai Xingwen; Dong Jiaodi; Wang Xun; Wang Jianhua

2003-01-01

Effects of X- and γ-irradiation on the ultrastructure change of Hematococcus pluvialis has been studied. The results show that X or γ irradiation causes different damages on different cell organelles such as the cytolemma be lacerated, the bioplasm excursed, the area of thin electron occurred in nucleus, the chloroplast lacerated, the thylakoids ruptured, the ribosome increased, the plastosome inflated and its membrane lacerated. In addition, X-irradiation causes perforation of starch sheath, decrease of SER and inducing of lycotropal pyrenoid. γ-irradiation causes dissolving of starch sheath, increase of SER and inflation of golgi body. The mutation effects of X- and γ-irradiation on the cell are probably caused by the laceration of some cell organelles like nucleolus, chloroplast and plastosome

An ultrastructural study of the chromatoid body in planarian regenerative cells

International Nuclear Information System (INIS)

Hori, Isao

1982-01-01

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

Simultaneous detection of multiple targets for ultrastructural immunocytochemistry

Czech Academy of Sciences Publication Activity Database

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

2014-01-01

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

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

Science.gov (United States)

Ekici, Nuran; Dane, Feruzan; Olgun, Göksel

2013-09-01

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

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

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Leander Brian S

2009-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

1980-01-01

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

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

Science.gov (United States)

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

1994-08-01

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

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

Science.gov (United States)

Shapiro, Adam J; Leigh, Margaret W

2017-01-01

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

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

African Journals Online (AJOL)

Yomi

2011-12-28

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

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

Czech Academy of Sciences Publication Activity Database

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

2009-01-01

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

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

Czech Academy of Sciences Publication Activity Database

Bruňanská, Magdaléna; Nebesářová, Jana; Scholz, Tomáš

2003-01-01

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

Biochemical and ultrastructural changes in pollen of Zea mays L. grown under enhanced UV-B radiation

International Nuclear Information System (INIS)

Santos, A.; Almeida, J.M.; Santos, I.; Salema, R.

1998-01-01

The influence of ultraviolet-B (UV-B) radiation on the development of the male gametophyte was studied in Zea mays L. cv. LG12 grown in a growth chamber under PAR light supplemented with UV-B radiation and compared with a second set of plants grown under PAR light. Pollen samples collected from both groups of plants were cultured on germination medium and it was found that UV-B had no effect on pollen germination. Total pollen protein content was not affected but UV-B absorbing pigments increased. Some ultrastructural alterations were observed in pollen and pollen tubes, in particular large amounts of electron dense deposits were seen throughout the cytoplasm and in association with the pollen wall. In mature spikes of UV-B treated plants, anthers retained numerous pollen grains in their loculi while anthers of control plants were almost empty. UV-B treatment delayed flowering by 2±3 d. These results show that UV-B treatment of maize plants interferes with flowering, pollen ultrastructure and anther maturation even though pollen germination is unaffected. The significant increase of UV-B absorbing pigments in pollen grains could represent a defence mechanism that enables plants to complete their reproductive cycle. (author)

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

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Guohua Ding

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

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

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Ahmed Mahmoud Halawa

2016-06-01

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

Experimental chronic entrapment of the sciatic nerve in adult hamsters: an ultrastructural and morphometric study

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Prinz R.A.D.

2003-01-01

Full Text Available Entrapment neuropathy is a group of clinical disorders involving compression of a peripheral nerve and interference with nerve function mostly through traction injury. We have investigated the chronic compression of peripheral nerves as an experimental procedure for detecting changes in ultrastructural nerve morphology. Adult hamsters (Mesocricetus auratus, N = 30 were anesthetized with a 25% pentobarbital solution and received a cuff around the right sciatic nerve. Left sciatic nerves were not operated (control group. Animals survived for varying times (up to 15 weeks, after which they were sacrificed and both sciatic nerves were immediately fixed with a paraformaldehyde solution. Experimental nerves were divided into segments based upon their distance from the site of compression (proximal, entrapment and distal. Semithin and ultrathin sections were obtained and examined by light and electron microscopy. Ultrastructural changes were qualitatively described and data from semithin sections were morphometrically analyzed both in control and in compressed nerves. We observed endoneurial edema along with both perineurial and endoneurial thickening and also the existence of whorled cell-sparse structures (Renaut bodies in the subperineurial space of compressed sciatic nerves. Morphometric analyses of myelinated axons at the compression sites displayed a remarkable increase in the number of small axons (up to 60% in comparison with the control axonal number. The distal segment of compressed nerves presented a distinct decrease in axon number (up to 40% comparatively to the control group. The present experimental model of nerve entrapment in adult hamsters was shown to promote consistent histopathologic alterations analogous to those found in chronic compressive neuropathies.

Fluorescence Localization and Comparative Ultrastructural Study of Periplocoside NW from Periploca sepium Bunge in the Midgut of the Oriental Amyworm, Mythimna separata Walker (Lepidoptera: Noctuidae

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Mingxing Feng

2014-05-01

Full Text Available Periplocoside NW (PSNW is a novel insecticidal compound isolated from the root bark of Periploca sepium Bunge and has potent stomach toxicity against some insect pests. Previous studies showed that the Mythimna separata larva is sensitive to PSNW, but the Agrotis ispilon larva is insensitive. In this study, preliminary target localization on the midgut of M. separata larvae was conducted via a fluorescence labeling technique. A comparative ultrastructural study on the effects of PSNW on the midguts of M. separata and A. ispilon larvae was performed. Symptom observation results showed that typical stomach toxicity was induced by PSNW in M. separata larvae. Fluorescence localization results showed that PSNW binds to the midgut cells of M. separata larvae. Ultrastructure observations showed destruction of the microvilli, organelle, and cytomembrane in the midgut cells of M. separata larvae, whereas no obvious changes were observed in midgut cells of A. ispilon larvae. These results were consistent with the insecticidal activity of PSNW. Therefore, PSNW might act on the midgut tissues of the insects, and one or more binding sites of PSNW may exist in M. separata larvae midgut cell cytomembranes.

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

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A. D. Singh

2016-03-01

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

Ultrastructural characteristics of the uterine epithelium of aspidogastrean and digenean trematodes

Czech Academy of Sciences Publication Activity Database

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

2011-01-01

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

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

Czech Academy of Sciences Publication Activity Database

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

2004-01-01

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

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

DEFF Research Database (Denmark)

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

1992-01-01

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

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

Science.gov (United States)

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.

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

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Perendija Branka R.

2011-01-01

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

Histochemical and ultrastructural study of an elastofibroma dorsi coexisting with a high grade spindle cell sarcoma

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M Alberghini

2009-06-01

Full Text Available Elastofibroma dorsi is a pseudotumoral fibroproliferative lesion characterized by polymorphic fiber-like deposits of elastinophilic material. Several theories have been reported explaining the pathogenesis of elastofibroma. Recent cytogenetic studies have demonstrated chromosomal instability in elastofibromas, not normally observed in non-neoplastic tissues. These chromosomal defects are commonly observed in aggressive fibromatosis too. Such clinical observations suggest a multistage pathogenetic mechanism for the onset of elastofibroma. This study, using histochemical, immunohistochemical staining techniques, and ultrastructural examination, describes the detection of an otherwise typical elastofibroma contextual to a high grade sarcoma. Hence, the coexistence of elastofibroma and high-grade sarcoma may suggest a causal link between the two pathological entities. The results obtained suggest that the coexistence of the two pathological entities is conceivably coincidental.

Somatostatinoma: collision with neurofibroma and ultrastructural features.

Science.gov (United States)

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

2006-11-01

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

Colleters in Caryocar brasiliense (Caryocaraceae ontogenesis, ultrastructure and secretion

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E. A. S. Paiva

Full Text Available Colleters are widely distributed and have been reported in several taxa. However, the only report of colleters in the Caryocaraceae family is in Caryocar brasiliense. This study purports to describe the distribution, structure and ultrastructure of colleters in C. brasiliense. Vegetative shoot apices with stipules in different stages of development were collected, fixed, and processed by light, transmission and scanning electron microscopy. Colleters occur on the stipule adaxial face and are differentiated on younger stipules, remaining functional until senescence. Stipules are deciduous, falling before the beginning of leaf expansion. Colleter secretion is abundant, filling all the space delimited by the stipule. Colleter origin is mixed, involving the protoderm and ground meristem. In this species, colleters are finger-shaped, consisting of a column of non-secretory central cells and a secretory epithelium whose cells are arranged in palisades. Secretory epithelium cells show dense cytoplasm, rough endoplasmic reticulum (RER segments, free ribosomes, mitochondria, and abundant well developed dictyosomes. The colleters central cell shows a flocculated cytoplasm and developed vacuole. These cells have a small lobated nucleus with an inconspicuous nucleolus. Mitochondria and RER stand out in the organelles. There is evidence of granulocrine secretion and colleter involvement with protection of the apical meristem and leaves in the initial stages of development.

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

Institute of Scientific and Technical Information of China (English)

孙云; 邓杨梅; 王德俊; 沈春锋; 刘晓梅; 张洪泉

2001-01-01

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

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

International Nuclear Information System (INIS)

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

1984-01-01

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

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

International Nuclear Information System (INIS)

Pavelka, M.; Gangl, A.

1983-01-01

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

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

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Braun Armin

2009-09-01

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

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

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Eleftherios P. Eleftheriou

2015-07-01

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

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

Czech Academy of Sciences Publication Activity Database

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

2016-01-01

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

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

Science.gov (United States)

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.

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

Science.gov (United States)

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

2016-01-01

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

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

International Nuclear Information System (INIS)

Yang Zhiyuan; Guo Yuefen; Lai Chixiang

1993-01-01

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

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

Czech Academy of Sciences Publication Activity Database

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

2012-01-01

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

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

Czech Academy of Sciences Publication Activity Database

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

2010-01-01

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

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

Science.gov (United States)

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

2015-02-01

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

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

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I. Bravo Portela

2012-01-01

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

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

Science.gov (United States)

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

2016-04-01

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

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

DEFF Research Database (Denmark)

Prentø, P

1997-01-01

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

The Effect of Spaceflight on the Ultrastructure of the Cerebellum

Science.gov (United States)

Holstein, Gay R.; Martinelli, Giorgio P.

2003-01-01

In weightlessness, astronauts and cosmonauts may experience postural illusions as well as motion sickness symptoms known as the space adaptation syndrome. Upon return to Earth, they have irregularities in posture and balance. The adaptation to microgravity and subsequent re-adaptation to Earth occurs over several days. At the cellular level, a process called neuronal plasticity may mediate this adaptation. The term plasticity refers to the flexibility and modifiability in the architecture and functions of the nervous system. In fact, plastic changes are thought to underlie not just behavioral adaptation, but also the more generalized phenomena of learning and memory. The goal of this experiment was to identify some of the structural alterations that occur in the rat brain during the sensory and motor adaptation to microgravity. One brain region where plasticity has been studied extensively is the cerebellar cortex-a structure thought to be critical for motor control, coordination, the timing of movements, and, most relevant to the present experiment, motor learning. Also, there are direct as well as indirect connections between projections from the gravity-sensing otolith organs and several subregions of the cerebellum. We tested the hypothesis that alterations in the ultrastructural (the structure within the cell) architecture of rat cerebellar cortex occur during the early period of adaptation to microgravity, as the cerebellum adapts to the absence of the usual gravitational inputs. The results show ultrastructural evidence for neuronal plasticity in the central nervous system of adult rats after 24 hours of spaceflight. Qualitative studies conducted on tissue from the cerebellar cortex (specifically, the nodulus of the cerebellum) indicate that ultrastructural signs of plasticity are present in the cerebellar zones that receive input from the gravity-sensing organs in the inner ear (the otoliths). These changes are not observed in this region in cagematched

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

Science.gov (United States)

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

2016-09-01

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

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

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M. Malatesta

2013-09-01

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

Ultrastructural observations of lethal yellow (A/sup y//A/sup y/) mouse embryos

Energy Technology Data Exchange (ETDEWEB)

Calarco, P G; Pedersen, R A

1976-01-01

A/sup y//A/sup y/ embryos were identified by the presence of large excluded blastomeres (Pedersen, 1974) and examined cytologically and ultrastructurally. Cell organelles, inclusions and junctions in the excluded blastomeres were compared with those of non-excluded cells of A/sup y//A/sup y/ embryos and control embryos. Excluded blastomeres always had the fine structural characteristics of earlier developmental stages and may have arrested at the 4- to 8-cell stage or slightly later. Interior cells (inner cell mass) were observed in all mutant blastocysts. Nonexcluded cells of A/sup y//A/sup y/ embryos were normal until degenerative changes appear in the late blastocyst stage. The mode of action of the +/sup A/sup y/ gene was not determined, but evidence from this study and others indicates that the effects of +/sup A/sup y/ gene action occur over a wide range of time in early cleavage and implantation.

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

International Nuclear Information System (INIS)

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

2012-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

Terrier, Olivier; Moules, Vincent; Carron, Coralie; Cartet, Gaeelle [Equipe VirCell, Laboratoire de Virologie et Pathologie Humaine, VirPath EMR 4610, Universite de Lyon, Universite Claude Bernard Lyon 1, Hospices Civils de Lyon, Faculte de medecine RTH Laennec, rue Guillaume Paradin, F-69008 Lyon (France); Frobert, Emilie [Laboratoire de Virologie, Centre de Biologie et de Pathologie Est, Hospices Civils de Lyon, 59 boulevard Pinel, F-69677 Bron Cedex, Lyon (France); Yver, Matthieu; Traversier, Aurelien [Equipe VirCell, Laboratoire de Virologie et Pathologie Humaine, VirPath EMR 4610, Universite de Lyon, Universite Claude Bernard Lyon 1, Hospices Civils de Lyon, Faculte de medecine RTH Laennec, rue Guillaume Paradin, F-69008 Lyon (France); Wolff, Thorsten [Division of Influenza/Respiratory Viruses, Robert Koch Institute, Nordufer 20, D-13353 Berlin (Germany); Riteau, Beatrice [Laboratoire de Virologie et Pathologie Humaine, VirPath EMR 4610, Universite de Lyon, Universite Claude Bernard Lyon 1, Hospices Civils de Lyon, Faculte de medecine RTH Laennec, rue Guillaume Paradin, F-69008 Lyon (France); Naffakh, Nadia [Institut Pasteur, Unite de Genetique Moleculaire des Virus Respiratoires, URA CNRS 3015, EA302 Universite Paris Diderot, Paris (France); and others

2012-10-10

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 subtype 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.

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

International Nuclear Information System (INIS)

Terrier, Olivier; Moules, Vincent; Carron, Coralie; Cartet, Gaëlle; Frobert, Emilie; Yver, Matthieu; Traversier, Aurelien; Wolff, Thorsten; Riteau, Beatrice; Naffakh, Nadia

2012-01-01

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 subtype 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.

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

NARCIS (Netherlands)

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

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

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

Czech Academy of Sciences Publication Activity Database

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

2011-01-01

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

Subcellular Sequestration and Impact of Heavy Metals on the Ultrastructure and Physiology of the Multicellular Freshwater Alga Desmidium swartzii

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Ancuela Andosch

2015-05-01

Full Text Available Due to modern life with increasing traffic, industrial production and agricultural practices, high amounts of heavy metals enter ecosystems and pollute soil and water. As a result, metals can be accumulated in plants and particularly in algae inhabiting peat bogs of low pH and high air humidity. In the present study, we investigated the impact and intracellular targets of aluminum, copper, cadmium, chromium VI and zinc on the filamentous green alga Desmidium swartzii, which is an important biomass producer in acid peat bogs. By means of transmission electron microscopy (TEM and electron energy loss spectroscopy (EELS it is shown that all metals examined are taken up into Desmidium readily, where they are sequestered in cell walls and/or intracellular compartments. They cause effects on cell ultrastructure to different degrees and additionally disturb photosynthetic activity and biomass production. Our study shows a clear correlation between toxicity of a metal and the ability of the algae to compartmentalize it intracellularly. Cadmium and chromium, which are not compartmentalized, exert the most toxic effects. In addition, this study shows that the filamentous alga Desmidium reacts more sensitively to aluminum and zinc when compared to its unicellular relative Micrasterias, indicating a severe threat to the ecosystem.

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

Science.gov (United States)

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

2015-01-01

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

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

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Jian-wei CHEN

2012-01-01

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

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

DEFF Research Database (Denmark)

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

2011-01-01

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

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

Czech Academy of Sciences Publication Activity Database

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

2012-01-01

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

Biochemical and ultrastructural processing of [125I]epidermal growth factor in rat epidermis and hair follicles: accumulation of nuclear label

International Nuclear Information System (INIS)

Green, M.R.; Mycock, C.; Smith, C.G.; Couchman, J.R.

1987-01-01

Although the intracellular ultrastructural processing of epidermal growth factor (EGF) and its receptor have been described in cell culture systems, very few studies have examined this phenomenon in intact tissues. We have examined the ultrastructural and biochemical handling of [ 125 I]EGF in the epidermis and hair follicle bulb of intact, viable, 3- to 5-day-old rat skin the EGF receptor distribution of which has already been documented and in which EGF has been shown to be biologically active. After incubation of explants with 10 nM [ 125 I]EGF for 2.5 h at 25 degrees or 37 degrees C, radiolabel was detected over the basal cells of the epidermis and hair follicle outer root sheath, confirming previous light microscope observations. More specifically, silver grains were observed near coated and uncoated plasma membrane and coated membrane invaginations, Golgi apparatus, lysosomal structures, and nuclei. Sodium azide inhibited internalization of label, whereas a series of lysosomal inhibitors (chloroquine, monensin, and iodoacetamide) caused a slight increase in silver grains associated with lysosomal vesicles and a decrease in nuclear label. Biochemical analysis indicated that greater than 35% of radioactivity following incubation at 37 degrees C was in the form of degraded [ 125 I]EGF fragments and that inclusion of chloroquine, monensin, and iodoacetamide reduced this value to 20.8%, 8.6%, and 4.0%, respectively. In addition, chloramine T-prepared [ 125 I]EGF was found to be covalently cross-linked with low efficiency to a protein having the molecular weight of the EGF receptor. These data are discussed in the light of the effects of EGF on epithelial cell proliferation in skin

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

Czech Academy of Sciences Publication Activity Database

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

2007-01-01

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

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

Czech Academy of Sciences Publication Activity Database

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

2010-01-01

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

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

Science.gov (United States)

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

1981-08-15

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

Effects of ultraviolet radiation on mole rats kidney: A histopathologic and ultrastructural study

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Hüseyin Türker

2014-04-01

Full Text Available The purpose of this study was to realize the ultrastructural effects of ultraviolet radiation on the kidney tissue cells of mole rats (Spalax leucodon. The mole rats of 180–200 g body weight were divided into the control and radiation-trial groups. The control group was not given any radiation. The other groups were irradiated with artificially produced UVC radiation for 14, 28 and 60 days. The kidney tissue samples were prepared at the end of experiments and analyzed by the light and electron microscope. Several effects were observed in the kidney tissues cells analyzed in accordance with the dose magnitude of radiation. These results clearly show the detrimental effects of UVC radiation on kidney tissue cells in exposure periods dependent on radiation dose and exposure time.

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

Science.gov (United States)

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.

The Effectiveness of Natural Diarylheptanoids against Trypanosoma cruzi: Cytotoxicity, Ultrastructural Alterations and Molecular Modeling Studies.

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Vitor Sueth-Santiago

Full Text Available Curcumin (CUR is the major constituent of the rhizomes of Curcuma longa and has been widely investigated for its chemotherapeutic properties. The well-known activity of CUR against Leishmania sp., Trypanosoma brucei and Plasmodium falciparum led us to investigate its activity against Trypanosoma cruzi. In this work, we tested the cytotoxic effects of CUR and other natural curcuminoids on different forms of T. cruzi, as well as the ultrastructural changes induced in epimastigote form of the parasite. CUR was verified as the curcuminoid with more significant trypanocidal properties (IC50 10.13 μM on epimastigotes. Demethoxycurcumin (DMC was equipotent to CUR (IC50 11.07 μM, but bisdemethoxycurcumin (BDMC was less active (IC50 45.33 μM and cyclocurcumin (CC was inactive. In the experiment with infected murine peritoneal macrophages all diarylheptanoids were more active than the control in the inhibition of the trypomastigotes release. The electron microscopy images showed ultrastructural changes associated with the cytoskeleton of the parasite, indicating tubulin as possible target of CUR in T. cruzi. The results obtained by flow cytometry analysis of DNA content of the parasites treated with natural curcuminoids suggested a mechanism of action on microtubules related to the paclitaxel`s mode of action. To better understand the mechanism of action highlighted by electron microscopy and flow cytometry experiments we performed the molecular docking of natural curcuminoids on tubulin of T. cruzi in a homology model and the results obtained showed that the observed interactions are in accordance with the IC50 values found, since there CUR and DMC perform similar interactions at the binding site on tubulin while BDMC do not realize a hydrogen bond with Lys163 residue due to the absence of methoxyl groups. These results indicate that trypanocidal properties of CUR may be related to the cytoskeletal alterations.

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

Science.gov (United States)

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

2016-09-01

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

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

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Anne K. Braczynski

2015-01-01

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

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

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Dina Sibouakaz

2018-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

1988-01-01

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

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

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Leiting Pan

2018-01-01

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

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

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Visitación T. Conforti

2017-11-01

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

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

Science.gov (United States)

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

2014-10-01

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

Micromorphological study (ultrastructure of lamina surface, seeds, ultrasculpture of pollen grains of Gladiolus L. species (Iridaceae Juss. of Ukrainian flora

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Zhygalova Svitlana L.

2014-12-01

Full Text Available Micro-morphological characteristics of the four Gladiolus L. species of the Ukrainian flora (G. imbricatus L., G. italicus Mill., G. palustris Gaudin and G. tenuis M. Bieb. as regards leaves, seeds and pollens are presented with this investigation in a detailed way. An examination of the surface structure of the leaves, seeds and pollen grains of the Gladiolus species indicates that the characteristics of the ultrastructure of leaves and of pollen grains are not diagnostic for distinguishing species, but they could be important at genus level (leaves: features such as being amphistomatic, having the same quantity of immersed stomata on both surfaces and having a high stomata index, the presence and localisation of papillae, the shape of epidermal cells; pollen grains: monosulcate type with two operculums. However, the type of surface ultrastructure of the seed coat is a diagnostic feature as at genus level so for species. It can be mentioned that propose the use of features such as the shape and position of the cicatricle, the type of cuticle, the shape and boundaries of cells of testa, and the anticlinal cell walls as diagnostic features at genera level. The shape of seeds, the presence and disposition of wing, the level of the periclinal cell walls of the seed coat and types of relief are additional diagnostic features for distinguishing of Gladiolus species.

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

NARCIS (Netherlands)

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

2008-01-01

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

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

Czech Academy of Sciences Publication Activity Database

Schnablová, Renáta; Synková, Helena; Čeřovská, Noemi

2005-01-01

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

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

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P. Dorfmüller

2010-01-01

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

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

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

2013-09-01

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

Herbicide effects on cuticle ultrastructure in Eleusine indica and Portulaca oleracea.

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Malpassi, Rosana N

2006-04-01

Eleusine indica and Portulaca oleracea are two common weeds in peanut crops in southern Córdoba. Two chemicals are frequently used to control them, quizalofop for grasses and lactofen for dicots. The objective is to study the effects of quizalofop and lactofen on cuticle ultrastructure in E. indica and P. oleracea, respectively. In the lab, quizalofop was applied on E. indica and lactofen on P. oleracea. Three plant categories were analyzed in each species: 3, 1-2, and no tiller in E. indica, and 8, 6, and 2 nomophylls in P. oleracea. Leaf samples from both species were collected at 7 and 16 days post-application and were treated for scanning electron microscopy. E. indica cuticle treated with lethal dose shows areas where epicuticular waxes disappear, specially in the youngest individuals. These areas are located predominantly on periclinal walls of typical epidermic cells and subsidiary cells. On the other hand, P. oleracea shows cuticle discontinuities that may be caused by lactofen entry. They are smaller and less frequent in plants having 8 or more nomophylls. The remaining waxes act as a herbicide accumulation compartment and, therefore, would partially prevent the active ingredient entry to epidermic cells.

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

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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.

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

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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.

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

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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.

Ultrastructural changes of photodegradation of wood surfaces exposed to UV

International Nuclear Information System (INIS)

Kuo, M.L.; Hu, N.

1991-01-01

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

Ultrastructure of rat cerebral vessels 4 months after gamma irradiation

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Iwanowski, L; Ostenda, M

1975-01-01

The purpose of this paper was to check the current opinion that one of the late postirradiation changes is early senility (Maxwell, Kruger, 1964). The postirradiation changes of the brain parenchyma are well known from the literature; therefore our investigation is limited to brain capillaries and their closest vicinity. This paper constitutes a fragment of a larger work on the role of connective tissue in the aging brain. Six Wistar male rats of the same brood, about 3 months old, were irradiated over the whole body with gamma rays. Three rats were exposed to a dose of 400 R and three to 800 R. The chosen doses were the lowest and the highest, provoking brain edema but still not lethal. Four months after the exposure the rats were perfused with 4% glutaraldehyde intracardiacly and decapitated. Brain specimens were taken from frontoparietal cortex, lateral ventricle wall, from corpus callosum and griseum pontis. The samples were routinely handled for ultrastructural studies. Observations were performed under electron microscopes showed that the cerebral vessels of both groups of animals were similar.

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

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M. Miko

2015-10-01

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

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

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Danišovič, Ľ.; Majidi, A.; Varga, I.

2015-01-01

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

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

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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.

Extrahepatic bile duct ligation in broiler chickens: ultrastructural study of Ito cell

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Ekowati Handharyani

2004-12-01

Full Text Available The Ito cell (fat-storing cell is a cell lying in perisinusoidal space of liver. The function of Ito cell is expanding from a site of fat-storing site to a center of extracellular matrix metabolism and mediator production in the liver. This study was performed in order to evaluate the Ito cells in cholestatic condition. The artificial cholestatic was conducted by ligation of extrahepatic bile ducts (bile duct ligation = BDL in broilers. The results showed that BDL induced bile congestion, fibrosis, proliferation of Ito cells and intrahepatic bile ductules. Immunohistochemistry demonstrated that Ito cells were scattered throughout the fibrotic areas, and larger in size with more extensive immunoreactivity than those in normal livers. Ultrastructural study demonstrated that Ito cells were closely associated with the production of extracellular collagen fibers. Ito cells actively react against hepatocytic injuries, especially in fibrogenesis of cholestatic livers.

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

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

2001-12-01

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

Changes in ultrastructure and cytochemistry of the agarophyte Gracilaria domingensis (Rhodophyta, Gracilariales) treated with cadmium.

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dos Santos, Rodrigo W; Schmidt, Éder C; Bouzon, Zenilda L

2013-02-01

The agarophyte macroalgae Gracilaria domingensis (Kützing) Sonder ex Dickie is widely distributed along the Brazilian coast. While this species produces agarana, it is more important in the human diet. Therefore, the present study aimed to evaluate the biological effects of cadmium on its morphology and cellular organization. To accomplish this, the effects of cadmium in apical segments of G. domingensis were examined in vitro. Over a period of 16 days, the segments were cultivated and exposed to photosynthetically active radiation (PAR) at 80 μmol photons m(-2) s(-1), with cadmium treatments in doses of 100, 200 and 300 μM. The samples were processed for light, transmission and scanning electron microscopy. Histochemical analyses included Toluidine Blue for acidic polysaccharides, Coomassie Brilliant Blue for total protein, and Periodic Acidic Schiff for neutral polysaccharides. In all cadmium treatments, cytochemical analysis showed 1) metachromatic granulation in vacuole and lenticular thickness of the cell wall, 2) a higher concentration of cytoplasmic organelles, and 3) an increase in the number of floridean starch grains. Cadmium also caused changes in the ultrastructure of cortical and subcortical cells, including increased cell wall thickness and vacuole volume, as well as the destruction of chloroplast internal organization and increased number of plastoglobuli. In addition, treated plants showed a gradual increase in surface roughness, apparently the result of cadmium absorption. Taken together, these findings strongly suggested that cadmium negatively affects the agarophyte G. domingensis, posing a threat to the vitality of this plant species as a supplement in the human diet.

Ultrastructural study of myelinating cells and sub-pial astrocytes in developing rat spinal cord.

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Nagashima, K

1979-12-01

The anterior funiculus of the spinal cervical cord of post-natal rats was examined ultrastructurally. The myelinating cells found one day after brith contained a large amount of evenly distributed ribosomes up to the outer tongue of mesaxons, representing the cytoplasmic density. These cells were separated by astrocytic processes from the pial basement membrane, even when they were located on the pial surface. Astrocytes contained glial fibrils from one day onwards and often attached their processes to the pial basement membrane. Although the cytoplasmic processes of astrocytes occasionally wrapped axons, they were never shown to form the initial layer of myelin sheaths. However, the tenuous processes of the sub-pial astrocytes were occasionally rolled in myelin lamellae, as if a part of the myelin sheaths was constructed by astrocytic processes. The interpretation for this finding is discussed in relation to function and potency of the astrocytes, and variations and anomalies of nervous ontogeny.

Ultrastructural changes following electron irradiation in three-dimensional culture of normal human dermal fibroblasts

International Nuclear Information System (INIS)

Han, Chunmao; Ishikura, Naotaka; Tsukada, Sadao

1994-01-01

The present study was designed to examine the effect of electron irradiation on fibroblasts and extracellular matrices electron-microscopically. The three-dimensional dermal fibroblast culture was exposed to one, 4 or 10 Gy of electron beams. One day after irradiation, fibroblasts were vacuolated in all irradiated groups and intercellular spaces were increased in a dose-dependent manner. Seven days later, intercellular spaces became dense in both one and 4 Gy groups, although they were still extremely increased in the 10 Gy group. The remaining fibroblasts were still activated in all groups. Thirty days after irradiation, myofibroblastic cells were scarcely observed, but extracellular fine fibrils and collagen fibrils were observed in all irradiated groups. The other ultrastructural findings were similar to those in the control group. In conclusion, electron beams damaged not only cells but also extracellular matrix. The extracellular matrix may be repaired by activated residual fibroblasts, resulting in the mixture of new and old collagen fibrils having different diamters. (N.K.)

Ultrastructural study of tissues surrounding replanted teeth and dental implants.

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

2009-03-01

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

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

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

2017-04-01

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

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

International Nuclear Information System (INIS)

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

2013-01-01

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

Ultra-estrutura dos mastócitos de diferentes tipos histológicos de mastocitoma em cães Mast cell ultrastructure in different types of canine mast cell tumor

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F.A.R. Sueiro

2002-06-01

Full Text Available Este trabalho teve por objetivo estudar as diferenças ultraestruturais de mastócitos neoplásicos de diferentes tipos histológicos de mastocitoma em cães, usando microscopia eletrônica de transmissão Os resultados mostraram que o núcleo e os grânulos citoplasmáticos são as estruturas mais indicadas para se avaliar o grau de anaplasia celular e o estádio de indiferenciação do tumor.The objective of this work was study the ultrastructural differences among the different histologic types of mast cell tumors in dogs collected in vivo. The ultrastructural analyses showed that the nuclei and cytoplasmic granules characteristics are the best structures to be appointed on evaluating the undifferentiation stage of this tumor.

Influence of subinhibitory concentrations of antimicrobials on hydrophobicity, adherence and ultra-structure of Fusobacterium nucleatum

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Okamoto Ana C.

2002-01-01

Full Text Available Fusobacterium nucleatum is considered a bridge organism between earlier and later colonizers in dental biofilms and a putative periodontopathogen. In Dentistry, antimicrobial agents are used for treatment and control of infectious diseases associated with dental plaque. Antiseptics have been used in association with antibiotics to reduce infections after oral surgeries. In this study, the influence of subinhibitory concentrations (SC of chlorhexidine, triclosan, penicillin G and metronidazole, on hydrophobicity, adherence to oral epithelial cells, and ultra-structure of F. nucleatum was examined. All isolates were susceptible to chlorhexidine, triclosan, and metronidazole; however, most of the isolates were susceptible to penicillin G, and all of them were hydrophilic when grown with or without antimicrobials. Adherence was decreased by all antimicrobials. Results suggest that adherence of F. nucleatum was influenced by adhesins because structures such as fimbries or capsule were not observed by transmission electronic microscope.

Alloxan-Induced Diabetes Causes Morphological and Ultrastructural Changes in Rat Liver that Resemble the Natural History of Chronic Fatty Liver Disease in Humans

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Amanda Natália Lucchesi

2015-01-01

Full Text Available Purpose. This study evaluated the long-term effects of alloxan-induced diabetes in rat liver. Methods. Thirty nondiabetic control rats (NC and 30 untreated diabetic (UD rats were divided into three subgroups sacrificed after 6, 14, or 26 weeks. Clinical and laboratory parameters were assessed. Fresh liver weight and its relationship with body weight were obtained, and liver tissue was analyzed. Results. UD rats showed sustained hyperglycemia, high glycosylated hemoglobin, and low plasma insulin. High serum levels of AST and ALT were observed in UD rats after 2 weeks, but only ALT remained elevated throughout the experiment. Fresh liver weight was equal between NC and UD rats, but the fresh liver weight/body weight ratio was significantly higher in UD rats after 14 and 26 weeks. UD rats showed liver morphological changes characterized by hepatic sinusoidal enlargement and micro- and macrovesicular hepatocyte fatty degeneration with progressive liver structure loss, steatohepatitis, and periportal fibrosis. Ultrastructural changes of hepatocytes, such as a decrease in the number of intracytoplasmic organelles and degeneration of mitochondria, rough endoplasmic reticulum, and nuclei, were also observed. Conclusion. Alloxan-induced diabetes triggered liver morphological and ultrastructural changes that closely resembled human disease, ranging from steatosis to steatohepatitis and liver fibrosis.

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

Czech Academy of Sciences Publication Activity Database

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

2015-01-01

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

Post-mortem radiography of the lungs: Experiments to compare various methods of examination and descriptions of their usefulness in actual practice

International Nuclear Information System (INIS)

Pankow, W.

1986-01-01

Described is the post-mortem examination of the isolated lung using radiologic-morphologic and histologic methods. Comparisons are made ragarding practical value of the conservation techniques chosen, which were the method of Markaria and Heitzmann that is based on fixing in alcohol and air drying and the nitrogen freezing method developed by Rau and colleagues. Both methods ensure adequate visualition of the pulmonary ultrastructure by X-rays, even though this observation should be qualified by the fact that pulmonary tissue fixed in alcohol tends to shrink and that intraalveolar edema are thus artificially reduced. Either of the methods under investigation permits angiographic and bronchographic examinations to be carried out without difficulty. In macroscopic evaluations better results are obtained for lungs fixed in alcohol. Freeze-dried samples offer advantages in the histological assessment of the pulmonary ultrastructure. Post-mortem radiography of the lungs is particularly valuable in the analysis of pathological changes in the pulmonary structure. (MBC) [de

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

NARCIS (Netherlands)

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

1985-01-01

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

Effects of Vitamin D Treatment on Skeletal Muscle Histology and Ultrastructural Changes in a Rodent Model

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Sobhy M. Yakout

2012-07-01

Full Text Available Vitamin D is well known for its role in maintaining calcium and phosphorus homeostasis and in promoting bone mineralization; however, more of its pleiotropic effects have been described recently. The aim of the present investigation was to study the effect of vitamin D treatment on skeletal muscles changes under different dietary conditions using an animal model. Four groups of C57BL/6J mice (n = 11 each were maintained on either low fat diet (LFD or high fat diet ‎‎(HFD with and without 1α,25–dihydroxyvitamin D3 (calcitriol for 16 weeks. Animal weigh was recorded at baseline and then regular intervals, and at the end of the study, skeletal muscle tissues were harvested for the evaluation of the histopathological and ultrastructural changes. When control C57BL/6J mice were fed high-fat diet for 12 weeks, body weight gain was significantly increased compared with mice fed a LFD. (30.2% vs. 8.4%, p < 0.01. There was a significant gradual decrease in the weight of HFD fed mice that were treated with vitamin D as compared with a steady increase in the weights of controls (6.8% vs. 28.7%, p < 0.01. While the LFD group showed some ultrastructural changes, HDF fed on mice showed great muscle structural abnormalities. The whole sarcosome along with its membrane and cristae were severely damaged with scattered myocytes in HFD group. Furthermore, the mitochondria appeared weak and were on the verge of degenerations. The bands were diminished with loss of connections among myofibrils. These changes were attenuated in the HFD group treated with vitamin D with tissues have regained their normal structural appearance. The current findings indicate an important effect of vitamin D on skeletal muscle histology under HFD conditions.

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

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Norshalizah Mamikutty

2015-01-01

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

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

Science.gov (United States)

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

1993-03-01

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

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

Science.gov (United States)

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

1977-06-01

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

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

Science.gov (United States)

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.

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

Science.gov (United States)

1980-03-01

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

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

Science.gov (United States)

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

2015-01-01

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

The reorganization of root anatomy and ultrastructure of syncytial cells in tomato (Lycopersicon esculentum Mill. infected with potato cyst nematode (Globodera rostochiensis Woll.

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Sylwia Fudali

2011-01-01

Full Text Available The sequence of anatomical and ultrastructural events leading to the syncytium development in tomato roots infected with Globodera rostochiensis was examined. The syncytia were preferentially induced in cortical or pericyclic cells in the elongation zone of root. They developed towards the vascular cylinder by incorporation of new cells via local cell wall breakdown. After surrounding primary phloem bundle and reaching xylem tracheary elements syncytia spread along vascular cylinder. Roots in primary state of growth seemed to be the best place for syncytium induction as syncytia formed in the zone of secondary growth were less hypertrophied. At the ultrastructural level syncytial elements were characterized by strong hypertrophy, breakdown of central vacuole, increased volume of cytoplasm, proliferation of organelles, and enlargement of nuclei. On the syncytial wall adjoining vessels the cell wall ingrowths were formed, while the syncytial walls at interface of phloem were considerably thickened. They lacked of functional plasmodesmata and did not form any ingrowths. Using immunofluorescent-labelling and immunogold-labelling methods tomato expansin 5 protein was localized in nematode infected roots. The distribution of LeEXP A5 was restricted only to the walls of syncytia. The protein distribution pattern indicated that LeEXP A5 could mediates cell wall expansion during hypertrophy of syncytial elements.

Early ultrastructural changes in the dorsal mucosa of rat tongue after irradiation, with special reference to the microvasculature

International Nuclear Information System (INIS)

Obinata, Ken-ichi; Ohshima, Hayato; Ito, Jusuke; Takano, Yoshiro.

1997-01-01

To clarify the acute effects of irradiation on the ultrastructural conformation of the dorsal mucosa of the rat tongue, with special reference to the changes in microvasculature. The proboscis of seventy rats were irradiated. The animals were then perfusion-fixed, followed by India ink-injection or resin casting at 3 to 7 days after irradiation. The bulk, frozen sections, or plastic embedded sections of the treated rat tongues were examined by light and electron microscopy. In the dorsal epithelium of the rat tongue, multi-nucleated cells appeared in the basal layer at 3 days after irradiation. At day 5, the thickness of the epithelial layer and connective tissue papillae decreased dramatically, concomitant with the shortening of the capillary loops. At day 7, lingual papillae and connective tissue papillae disappeared, leaving dissociated epithelial cells and numerous neutrophils migrating throughout the tissue. Subepithelial blood vessels displayed drastic dilation with a number of neutrophils adhering to the endothelial surface, but without ultrastructural abnormalities in its cellular components. Early changes in the dorsal mucosa of the irradiated rat tongue were limited to the basal epithelial cells, leading to a total disruption of the epithelial layer. Atrophic changes of the capillary loops is due to the loss of the connective tissue papillae. Dilation and conformational changes of the subepithelial capillaries appear to result from the inflammatory reaction, taking place secondarily to the loss of the epithelial barrier of the irradiated tongue. A difference in radiosensitivity among the epithelial, endothelial, and mesenchymal cell components of the rat tongue in vivo is suggested. (author)

Ultrastructural Characterization of Zika Virus Replication Factories

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Mirko Cortese

2017-02-01

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

Pathology of mitochondria in MELAS syndrome: an ultrastructural study.

Science.gov (United States)

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

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

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

Science.gov (United States)

Knecht, H; Hedinger, C E

1982-09-01

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

Effects of high-altitude environment on cognitive function and ultrastructure in CA1 region of hippocampus of rats after sleep deprivation

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Jiang-hua SI

2014-04-01

Full Text Available Objective To investigate the effects of high-altitude environment on cognitive function and ultrastructure in CA1 region of the hippocampus of Wistar rats in sleep deprivation (SD.  Methods SD was induced in Wistar rats by employing "flower pot" technique. Sixty-four rats were randomly divided into 2 groups: Lanzhou group (at an altitude of 1520 m and Kekexili group (at an altitude of 4767 m, and each group was further divided into 4 subgroups according to the time of SD (0, 1, 3 and 5 d. The behaviors of rats were studied by Morris water maze test at given time points. The ultrastructure of hippocampal neurons was observed by transmission electron microscope (TEM.  Results 1 Compared with Lanzhou group, rat behavior of Kekexili group presented excitement-irritation-suppression changes with the extension of SD time, but the extent was weakened gradually, and time of sleepiness increased obviously. 2 Compared with Lanzhou group, neurons in CA1 region of hippocampus showed enlarged cell body, disappeared nuclear membrane, shrunken nuclei and decreased organelle. End-feet of glia cells sticking to capillaries swelled and ruptured, and the typical synaptic structure disappeared. 3 Morris water maze test: as compared with Lanzhou group, the escape latency of Kekexili group prolonged (P < 0.05, for all, the ability of distance exploration increased (P < 0.05, for all, and the times across plot decreased (P < 0.05, for all in 1, 3 and 5 d of SD.  Conclusions High-altitude environment may significantly influence the cognitive function of rats in SD, and there was close correlation between the cognitive disorders and the changes in the ultrastructure of hippocampal CA1 region. doi: 10.3969/j.issn.1672-6731.2014.04.012

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

Science.gov (United States)

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

2017-09-01

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

Digital Imaging Analysis for the Study of Endotoxin-Induced Mitochondrial Ultrastructure Injury

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Mandar S. Joshi

2000-01-01

Full Text Available Primary defects in mitochondrial function have been implicated in over 100 diverse diseases. In situ, mitochondria possess unique and well-defined morphology in normal healthy cells, but diseases linked to defective mitochondrial function are characterized by the presence of morphologically abnormal and swollen mitochondria with distorted cristae. In situ study of mitochondrial morphology is established as an indicator of mitochondrial health but thus far assessments have been via subjective evaluations by trained observers using discontinuous scoring systems. Here we investigated the value of digital imaging analysis to provide for unbiased, reproducible, and convenient evaluations of mitochondrial ultrastructure. Electron photomicrographs of ileal mucosal mitochondria were investigated using a scoring system previously described by us, and also analyzed digitally by using six digital parameters which define size, shape, and electron density characteristics of over 700 individual mitochondria. Statistically significant changes in mitochondrial morphology were detected in LPS treated animals relative to vehicle control using both the subjective scoring system and digital imaging parameters (p < 0:05. However, the imaging approach provided convenient and high throughput capabilities and was easily automated to remove investigator influences. These results illustrate significant changes in ileal mucosal mitochondrial ultrastructure during sepsis and demonstrate the value of digital imaging technology for routine assessments in this setting.

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

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Shadia Al-Bahlani

2017-01-01

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

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

Science.gov (United States)

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

2013-12-01

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

The morphology and ultrastructure of the nectaries of marrow (Cucurbita pepo L. convar. giromontiina

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Marta Dmitruk

2013-10-01

Full Text Available The present study investigated the size and structure of the nectaries in flowers of marrow – Cucurbita pepo convar. giromontiina cv. ‘Weiser Busch’. The diameter and thickness of nectariferous layer were compared in female and male flowers of this taxon. The micromorphology as well as the anatomical and ultrastructural characters of the nectary from the female flower were observed using light, scanning and transmission electron microscopy. The density and size of stomata of the nectary epidermis from both types of flowers were examined using light microscopy. The nectaries in female flowers were found to have a larger size than in male flowers. The stomata occurring in the nectary epidermis of both types of flowers have a similar size and density. We observed that nectar was released onto the surface of the nectary not only via the stomata, but also through the walls of the epidermal cells. In TEM examination, large nuclei, different-shaped plastids, ER tubules, dictyosomes, and ribosomes were observed in the nectariferous tissue cells. A large number of mitochondria accompanying the plastids were found in the parenchyma cells of the nectary. The degradation of the nectary parenchyma cells in the flowers living for about 6 hours was asynchronous.

Ultrastructural and some functional changes in tumor cells treated with stabilized iron oxide nanoparticles.

Science.gov (United States)

Yurchenko, O V; Todor, I N; Khayetsky, I K; Tregubova, N A; Lukianova, N Yu; Chekhun, V F

2010-12-01

To study the ultrastructure and some functional indexes of tumor cells treated with stabilized iron nanoparticles in vitro. 3-[4,5dimethylthiazol-2-1]-2,5-diphenyltetrazolium bromide (MTT)-test, electron microscopy, polarography with applying of closed Clark's electrode. It was shown that cultivation of cells with stabilized Fe(3)O(4) leads to intracellular accumulation of ferromagnetic nanoparticles. The most active ferromagnetic uptake by cells has been observed after 24 and 48 h of incubation. The presence of ferromagnetic in cells led to altered mitochondrial structure that caused the decrease of oxygen uptake rate in the cells of all studied lines. Ferromagnetic released from the majority of cells via exocytosis or clasmacytosis after a certain period of time. The number of dead cells or cells with severe damage was moderate, so cytotoxic action of stabilized iron oxide nanoparticles was minimal toward the studied cell lines. the presence of ferromagnetic nanoparticles in culture medium led to alterations in mitochondria ultrastructural organization and decrease of oxygen uptake by mitochondria in sensitive and anticancer-drugs resistant cells.

Human skin basement membrane-associated heparan sulphate proteoglycan: distinctive differences in ultrastructural localization as a function of developmental age

DEFF Research Database (Denmark)

Horiguchi, Y; Fine, J D; Couchman, J R

1991-01-01

was identical to that observed in neonatal and adult human skin. These findings demonstrate that active remodelling of the dermo-epidermal junction occurs during at least the first two trimesters, and affects not only basement membrane-associated structures but also specific antigens.......Recent studies have demonstrated that skin basement membrane components are expressed within the dermo-epidermal junction in an orderly sequence during human foetal development. We have investigated the ultrastructural localization of basement membrane-related antigens in human foetal skin...... at different developmental ages using two monoclonal antibodies to a well-characterized basement membrane-associated heparan sulphate proteoglycan. A series of foetal skin specimens (range, 54-142 gestational days) were examined using an immunoperoxidase immunoelectron microscopic technique. In specimens...

Salivary gland ultrastructure and cyclic AMP-dependent reactions in Spacelab 3 rats

International Nuclear Information System (INIS)

Mednieks, M.I.; Hand, A.R.

1987-01-01

Environmental stimuli influencing catecholamine levels induce changes in cyclic AMP-dependent reactions and cell morphology in the rat parotid. Responses of salivary glands to spaceflight were determined by measurement of cyclic AMP-mediated reactions in fresh-frozen salivary glands and by microscopic evaluation of ultrastructure in fixed parotid glands. Decreased cell-free protein phosphorylation, determined by autoradiography, occurred in parotid glands in three of five flight animals. Protein kinase activity ratios were decreased in the soluble and increased in the particulate fractions of Spacelab 3 (SL-3) rat sublingual glands, compared with ground controls. Biochemical analyses show that effects of space flight on salivary glands are similar to those induced experimentally by physiological manipulation or alteration of catecholamine levels. Morphological evaluation of three SL-3 rat parotid glands showed increased numbers of lysosomes, autophagic vacuoles containing degenerating secretory product, and accumulation of lipid droplets. Since these animals lost weight, consistent with disruption of food and water consumption, morphological changes may in part be due to decreased masticatory stimulation, as occurs with reduced food intake or a liquid diet. The observed changes may reflect physiological responses of the gastrointestinal and autonomic systems to effects of spaceflight

Comparative studies on intestine ultrastructure of third-stage larvae and adults of Cystidicoloides ephemeridarum (Nematoda, Cystidicolidae)

Czech Academy of Sciences Publication Activity Database

Frantová, Denisa; Moravec, František

2004-01-01

Roč. 94, č. 5 (2004), s. 377-383 ISSN 0932-0113 R&D Projects: GA AV ČR KJB6022305 Institutional research plan: CEZ:AV0Z6022909 Keywords : Nematoda * Cystidicolidae * ultrastructure Subject RIV: EG - Zoology Impact factor: 1.060, year: 2004

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

Energy Technology Data Exchange (ETDEWEB)

Cunha, E.V.; Costa, J.J.N.; Rossi, R.O.D.S.; Silva, A.W.B.; Passos, J.R.S.; Portela, A.M.L.R.; Pereira, D.C.S.T. [Núcleo de Biotecnologia de Sobral, NUBIS, Universidade Federal do Ceará, Sobral, CE (Brazil); Donato, M.A.M. [Laboratório de Ultraestrutura, CPqAM/FIOCRUZ, Universidade Federal de Pernambuco, Recife, PE (Brazil); Campello, C.C. [Laboratório de Manipulação de Oócitos e Folículos Pré-Antrais, Faculdade de Medicina Veterinária, Universidade Estadual do Ceará, Fortaleza, CE (Brazil); Saraiva, M.V.A. [Núcleo de Biotecnologia de Sobral, NUBIS, Universidade Federal do Ceará, Sobral, CE (Brazil); Peixoto, C.A. [Laboratório de Ultraestrutura, CPqAM/FIOCRUZ, Universidade Federal de Pernambuco, Recife, PE (Brazil); Silva, J.R.V.; Santos, R.P. [Núcleo de Biotecnologia de Sobral, NUBIS, Universidade Federal do Ceará, Sobral, CE (Brazil)

2013-03-19

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

The ultrastructure of bone and its relevance to mechanical properties

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

2017-09-01

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

Spermiogenesis and spermatozoon of the tapeworm Parabothriocephalus gracilis (Bothriocephalidea): Ultrastructural and cytochemical studies

Czech Academy of Sciences Publication Activity Database

Šípková, Lenka; Levron, Céline; Freeman, M.; Scholz, Tomáš

2010-01-01

Roč. 55, č. 1 (2010), s. 58-65 ISSN 1230-2821 R&D Projects: GA ČR GP524/07/P039; GA ČR GA524/08/0885; GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : Eucestoda * Bothriocephalidea * Parabothriocephalus gracilis * spermiogenesis * spermatozoon * ultrastructure Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.144, year: 2010

[The staphylococcal enterotoxin burden determines the ultrastructure of ciliated epithelia and inflammatory changes in maxillary sinus mucosa of rabbits].

Science.gov (United States)

Wei, Hongqi; Zhu, Zhengwen; Cao, Zhongsheng; Liu, Zhiyong; Wu, Xiaofan; Yuan, Hui

2014-12-01

To investigate the ultrastructure of ciliated epithelia and inflammatory changes upon repeated exposure to staphylococcal enterotoxin A (SEA) of different concentrations in the maxillary sinus mucosa of rabbits. The rabbits were randomly divided into 2 groups (24 rabbits per group): low-dose SEA group and high-dose SEA group. The low-dose SEA group and high-dose SEA group received daily injections of 0.6 ng of SEA (2 ml) and 60 ng of SEA (2 ml) into the left maxillary sinus of rabbits for 28 days, respectively. Concurrent treatment of the right maxillary sinus with normal saline was used as control. Six rabbits chosen randomly in two groups were examined by computed tomography (CT) scans and then sacrificed to obtain the sinus mucosa from the two-side of maxillary sinuses for histological assessment on days 3, 7, 14 and 28. To characterize the inflammatory changes of the sinus mucosa examined using light microscope, hematoxylin and eosin (HE) and toluidine blue staining was performed. Scanning and transmission electron microscopy were performed to observe ultrastructure of ciliated epithelia in the maxillary sinus mucosa. SPSS 13.0 software was used to analyze the data. On days 14 and 28, CT images showed opacification of the left maxillary sinus in the high-dose SEA group. The percentage of epithelial disruption was (22.73 ± 5.72) % and (30.79 ± 4.30)% in the high-dose SEA group respectively, and were significantly greater than those in the low-dose SEA group (5.12% ± 1.98% and 5.38% ± 1.64%, q value was 10.079 and 19.132) and control group (4.08% ± 1.29% and 4.81% ± 1.62%, q value was 11.016 and 19.592, respectively, all P microscope, loss of cilia was observed, a few compound cilia and cytoplasmic protrusion were found, an obvious stretching of the endoplasmic reticulum and an obvious turgescence of the mitochondria was also observed. However, in the low-dose SEA group on days 14 and 28, CT scan of the left maxillary sinus showed transparency; light

Ultrastructure of male genitalia of blow flies (Diptera: Calliphoridae) of forensic importance.

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Sontigun, Narin; Sanit, Sangob; Wannasan, Anchalee; Sukontason, Kom; Amendt, Jens; Yasanga, Tippawan; Sukontason, Kabkaew L

2018-03-01

Male genitalia of blow flies (Diptera: Calliphoridae) are distinctive in their morphological features and are often used for species identification. The aim of this work was to investigate the male genitalia of blow flies of medical and forensic importance from Thailand at the ultrastructural level, using scanning electron microscopy (SEM). Flies in two subfamilies were examined: Chrysomyinae [Chrysomya bezziana Villeneuve, Chrysomya chani Kurahashi, Chrysomya nigripes Aubertin, Chrysomya pinguis (Walker), Chrysomya rufifacies (Macquart), Chrysomya thanomthini Kurahashi & Tumrasvin, and Chrysomya villeneuvi Patton] and Luciliinae [Hemipyrellia ligurriens (Wiedemann), Hypopygiopsis infumata (Bigot), Hypopygiopsis tumrasvini Kurahashi, Lucilia cuprina (Wiedemann), Lucilia papuensis Macquart, Lucilia porphyrina (Walker), and Lucilia sinensis Aubertin]. Particular attention was paid to the main distinguishing features such as the shapes of the cercus and the surstylus, and the complex structure of the distiphallus. The differentiation of the male genitalia of these species at the SEM level is discussed and compared to the conditions in closely related species such as Chrysomya megacephala (Fabricius). A key for the identification of 14 blow fly species based on male genitalia is provided. Copyright © 2017 Elsevier B.V. All rights reserved.

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

International Nuclear Information System (INIS)

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

2015-01-01

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

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

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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.

Ultrastructure of the Interstitial Tissue in the Testis of the Egyptian Dromedary Camel (Camelus dromedarius

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M. I. Abd-Elaziz, A. M. Kassem, D. M. Zaghloul*, A. E. Derbalah and M. H. Bolefa

2012-01-01

Full Text Available The ultrastructural examination of the testicular interstitial tissue of Egyptian dromedary camel was performed to observe the seasonal changes. The activity of the interstitial tissue increased largely in spring. This was indicated by the large number of mature Leydig cells and two to three layers of myofibroblasts around the basal laminae of the seminiferous tubules with large blood vessels in the interstitial tissue. The testicular activity was moderate in winter as indicated by the lower number of immature Leydig cells. The lowest activity was in summer when Leydig cells became inactive with pyknotic nuclei. The cells of interstitial tissue lost their junctions with each other, leaving large intercellular spaces and myofibroblasts transformed to fibrocytes. The testicular activity began again to increase in autumn. The testicular activity of camel, however, did not stop in any season of the year, because even in non-breeding seasons a part of the interstitial tissue of the testis was active.

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

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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.

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

OpenAIRE

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

2014-01-01

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

Photokinetic and ultrastructural studies on porphyrin photosensitization of HeLa cells

International Nuclear Information System (INIS)

Milanesi, Carla; Sorgato, Fiorella; Jori, Giulio

1989-01-01

Liposome-bound haematoporphyrin or haematoporphyrin dimethylester, as well as haematoporphyrin dissolved in phosphate-buffered saline, were added to HeLa cell monolayers at a dose of 1 μg of porphyrin per 10 5 cells. After 2 min or 20 min incubation liposome-bound porphyrins were accumulated by cells in an about two-fold larger amount than the water-dissolved haematoporphyrin. This caused a more efficient photosensitization of HeLa cells by liposome-delivered porphyrins upon illumination with 366 nm light. Ultrastructural studies of HeLa cells, which had been incubated in a physiological medium for 24 h after the end of irradiation, showed that liposomal porphyrins induce an early and extensive endocytoplasmic damage, leading to mitochondrial swelling and vesiculation; changes of permeability of the cytoplasmic membrane are also evident, especially in the case of haematoporphyrin dimethylester. On the other hand, water-dissolved haematoporphyrin predominantly photosensitizes damage of the plasma membrane. The different pattern of cell photodamage probably reflects a different subcellular distribution of the photosensitizing drugs. (author)

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

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Juan P. Hernández-Fonseca

2009-01-01

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

Non-Fourier thermal transport induced structural hierarchy and damage to collagen ultrastructure subjected to laser irradiation.

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Sahoo, Nilamani; Narasimhan, Arunn; Dhar, Purbarun; Das, Sarit K

2018-05-01

Comprehending the mechanism of thermal transport through biological tissues is an important factor for optimal ablation of cancerous tissues and minimising collateral tissue damage. The present study reports detailed mapping of the rise in internal temperature within the tissue mimics due to NIR (1064 nm) laser irradiation, both for bare mimics and with gold nanostructures infused. Gold nanostructures such as mesoflowers and nanospheres have been synthesised and used as photothermal converters to enhance the temperature rise, resulting in achieving the desired degradation of malignant tissue in targeted region. Thermal history was observed experimentally and simulated considering non-Fourier dual phase lag (DPL) model incorporated Pennes bio-heat transfer equation using COMSOL Multiphysics software. The gross deviation in temperature i.e. rise from the classical Fourier model for bio-heat conduction suggests additional effects of temperature rise on the secondary structures and morphological and physico-chemical changes to the collagen ultrastructures building the tissue mass. The observed thermal denaturation in the collagen fibril morphologies have been explained based on the physico-chemical structure of collagen and its response to thermal radiation. The large shift in frequency of amides A and B is pronounced at a depth of maximum temperature rise compared with other positions in tissue phantom. Observations for change in band of amide I, amide II, and amide III are found to be responsible for damage to collagen ultra-structure. Variation in the concentration of gold nanostructures shows the potentiality of localised hyperthermia treatment subjected to NIR radiation through a proposed free radical mechanism.

High pressure processing of meat: effects on ultrastructure and protein digestibility.

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Kaur, Lovedeep; Astruc, Thierry; Vénien, Annie; Loison, Olivier; Cui, Jian; Irastorza, Marion; Boland, Mike

2016-05-18

The effects of high pressure processing (HPP, at 175 and 600 MPa) on the ultrastructure and in vitro protein digestion of bovine longissimus dorsi muscle meat were studied. HPP caused a significant change in the visual appearance and texture of the meat subjected to HPP at 600 MPa so that it appeared similar to cooked meat, unlike the meat subjected to HPP at 175 MPa that showed no significant visible change in the colour and texture compared to the raw meat. The muscles were subjected to digestion under simulated gastric conditions for 1 h and then under simulated small-intestinal conditions for a further 2 h. The digests were analysed using gel electrophoresis (SDS-PAGE) and ninhydrin assay for amino N. The effect of the acid conditions of the stomach alone was also investigated. Reduced SDS-PAGE results showed that pepsin-digested (60 min) HPP meats showed fewer proteins or peptides of high molecular weight than the pepsin-digested untreated meat, suggesting more breakdown of the parent proteins in HPP-treated meats. This effect was more pronounced in the muscles treated at 600 MPa. These results are in accordance with microscopy results, which showed greater changes in the myofibrillar structure after simulated gastric digestion of the sample processed at 600 MPa than at 175 MPa. Transmission electron microscopy also showed the presence of protein aggregates in the former sample, resulting probably from protein denaturation of sarcoplasmic proteins, in the subcellular space and between myofibrils; along with cell contraction (similar to that caused by heating) in the former.

Ultrastructure of the gut epithelium in Acheta domesticus after long-term exposure to nanodiamonds supplied with food.

Science.gov (United States)

Karpeta-Kaczmarek, Julia; Augustyniak, Maria; Rost-Roszkowska, Magdalena

2016-05-01

The biosafety of nanoparticles and the potential toxicity of nanopollutants and/or nanowastes are all currently burning issues. The increased use of nanoparticles, including nanodiamonds (ND), entails the real risk of their penetration into food chains, which may result in the contamination of animal and, as a result, human food. Knowledge about changes in the ultrastructure of tissues in organisms that have been exposed to ND is still very limited. The aim of the study was to describe the ultrastructure of the gut epithelium in Acheta domesticus after exposure to different concentrations of ND (0, 20 or 200 μg g(-1) - control, ND20 and ND200 groups, respectively) administered with food over a five-week period. The ultrastructure of the foregut, midgut and hindgut was assessed using Transmission Electron Microscopy (TEM). A number of changes in the structure of the gut in crickets that had consumed nanodiamond-contaminated food were observed. The epithelium of the midgut and hindgut were clearly damaged by ND, although the foregut was not affected. A positive relationship between the ND concentration in food and the degree of damage to the structure of epithelial cells was observed. Autophagy, especially mitophagy and reticulophagy, was activated in relation to the appearance of ND particles. A putative ND toxicity mechanizm is proposed. Extreme caution should be maintained when using nanodiamonds on a large scale. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

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

2015-01-01

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

The first data on the vitellogenesis of paruterinid tapeworms: an ultrastructural study of Dictyterina cholodkowskii (Cestoda: Cyclophyllidea)

Czech Academy of Sciences Publication Activity Database

Yoneva, Aneta; Kuchta, Roman; Mariaux, J.; Georgiev, B. B.

2017-01-01

Roč. 116, č. 1 (2017), s. 327-334 ISSN 0932-0113 Institutional support: RVO:60077344 Keywords : ultrastructure * vitellocytes * vitelline vesicles * Cestode * Cyclophyllidean * Dictyterina cholodkowskii Subject RIV: EG - Zoology OBOR OECD: Zoology Impact factor: 2.329, year: 2016

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

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Worachote Boonsriwong

2012-01-01

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

Ultrastructural and stereological analysis of trypanosomatidis of the genus Endotrypanum

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Maurílio J. Soares

1991-06-01

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

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

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

2017-08-01

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

Scleral ultrastructure and biomechanical changes in rabbits after negative lens application

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Xiao Lin

2018-03-01

Full Text Available AIM: To address the microstructure and biomechanical changes of the sclera of rabbits after negative lens application by spectacle frame apparatus. METHODS: Five New Zealand rabbits of seven weeks post-natal were treated with -8 D lens monocularly over the course of two weeks. Refractive errors and axial length (AXL were measured at the 1st, 7th and 14th days of the induction period. Ultrastructure of sclera was determined with electron microscopy. Biomechanical properties were tested by an Instron 5565 universal testing machine. RESULTS: Lens-induced (LI eyes elongated more rapidly compared with fellow eyes with AXL values of 15.56±0.14 and 15.21±0.14 mm (P<0.01. Fibril diameter was significantly smaller in the LI eyes compared with control ones in the inner, middle, and outer layers (inner layer, 63.533 vs 76.467 nm; middle layer, 92.647 vs 123.984 nm; outer layer, 86.999 vs 134.257 nm, P<0.01, respectively. In comparison with control eyes, macrophage-like cells that engulfed fibroblasts, dilated endoplasmic reticulum, and vacuoles in fibroblasts were observed in the inner and middle stroma in the LI eyes. Ultimate stress and Young’s modulus were lower in the LI eyes compared with those in the control eyes. CONCLUSION: Negative lens application alters eye growth, and results in axial elongation with changes in scleral ultrastructural and mechanical properties.

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

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

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Marta Solé

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

Surface ultrastructure of Chrysomya rufifacies (Macquart) larvae (Diptera: Calliphoridae).

Science.gov (United States)

Sukontason, Kabkaew L; Sukontason, Kom; Lertthamnongtham, Sirisuda; Kuntalue, Budsabong; Thijuk, Natchanart; Vogtsberger, Roy C; Olson, Jimmy K

2003-05-01

The surface ultrastructure of all larval instars of Chrysomya rufifacies (Macquart) is described by means of scanning electron microscopy (SEM). Morphological changes were greatest from the first to the second instar, but less from the second to the third instar. Most of these changes involved the structure of the anterior spiracle, posterior spiracle, integument of the body, and mouthhooks. Modification of the mouthhooks, especially in the third instar, are helpful in explaining the ferocious feeding ability of the older maggots. The common name of "hairy-maggot" for C. rufifacies is only appropriate for the second and third instars because of their elongated tubercles along the body, whereas this name is not descriptive of the first instar that lack tubercles.

Ultrastructure of interstitial cells of Cajal associated with deep muscular plexus of human small intestine

DEFF Research Database (Denmark)

Rumessen, J J; Mikkelsen, H B; Thuneberg, L

1992-01-01

Evidence showing that interstitial cells of Cajal have important regulatory functions in the gut musculature is accumulating. In the current study, the ultrastructure of the deep muscular plexus and associated interstial cells of Cajal in human small intestine were studied to provide a reference...... a continuous basal lamina, caveolae, intermediate filaments, dense bodies, dense bands, and a well-developed subsurface smooth endoplasmic reticulum), but the arrangement of organelles was clearly different, and cisternae of granular endoplasmic reticulum were abundant. Interstitial cells of Cajal were......, and only few gap junctions with other interstitial cells of Cajal or with the musculature were observed. Compared with interstitial cells of Cajal from other mammals, those associated with the deep muscular plexus in the human small intestine more closely resemble smooth muscle cells...

Ultrastructural aspects in perithecia hyphae septal pores of Glomerella cingulata F. SP. Phaseoli

OpenAIRE

Roca M.,María Gabriela; Ongarelli,Maria das Graças; Davide,Lisete Chamma; Mendes-Costa,Maria Cristina

2000-01-01

Glomerella cingulata (Stonem.) Spauld. & Schrenk f. sp. phaseoli, better known in its anamorphic state Colletotrichum lindemuthianum (Sacc. & Magn.) Briosi & Cav., is a causal agent of anthracnose in beans (Phaseolus vulgaris L.). Ultrastructural aspects of the perithecial hyphae of this pathogen were studied. The perithecia hyphae septal pores were found either plugged by a vesicle or unplugged. Some perithecia hyphae septa presented no pore. The Woronin bodies, close to the sept...

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

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S. Muszyński

2015-01-01

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

The effect of pneumatic tourniquets on the ultrastructure of skeletal muscle.

Science.gov (United States)

Patterson, S; Klenerman, L

1979-05-01

Experiments have been carried out on rhesus monkeys to determine the effect of the application of a pneumatic tourniquet on the ultrastructure of the muscles of the lower limb. Tourniquets were applied for periods lasting between one and five hours. The changes in the muscle lying immediately under the cuff of the tourniquet were more marked than those observed in muscle distal to the cuff. Three hours appears to be close to the limit of the time that a muscle can resist the sustained compression of a tourniquet.

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

Science.gov (United States)

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

2011-07-01

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

Long-term effects of elevated UV-B radiation on photosynthesis and ultrastructure of Eriophorum russeolum and Warnstorfia exannulata

International Nuclear Information System (INIS)

Haapala, Jaana K.; Moersky, Sami K.; Saarnio, Sanna; Suokanerva, Hanne; Kyroe, Esko; Silvola, Jouko; Holopainen, Toini

2010-01-01

The depletion of stratospheric ozone above the Arctic regions may increase the amount of UV-B radiation to which the northern ecosystems are exposed. In this paper, we examine the hypothesis that supplemental UV-B radiation may affect the growth rate and photosynthesis of boreal peatland plants and could thereby affect the carbon uptake of these ecosystems. In this study, we report the effects of 3-year exposure to elevated UV-B radiation (46% above ambient) on the photosynthetic performance and ultrastructure of a boreal sedge Eriophorum russeolum and a moss Warnstorfia exannulata. The experiment was conducted on a natural fen ecosystem at Sodankylae in northern Finland. The effects of UV-B radiation on the light response of E. russeolum CO 2 assimilation and the maximal photochemical efficiency of photosystem II in a dark-adapted state (F v /F m ) were measured in the field. In addition, the effect of supplemental UV-B radiation on organelles of photosynthetic cells was studied by electron microscopy. The UV-B treatment had no effect on the CO 2 assimilation rate of either species, nor did it affect the structure of the cell organelles. On chlorophyll fluorescence, the UV-B exposure had only a temporary effect during the third exposure year. Our results suggested that in a natural ecosystem, even long-term exposure to reasonably elevated UV-B radiation levels does not affect the photosynthesis of peatland plants. - Research highlights: →Eriophorum russeolum and Warnstorfia exannulata are resistant to UV-B radiation →UV-B exposure does not affect the growth or photosynthesis of E. russeolum →Long-term UV-B exposure has no effect on the ultrastructure of E. russeolum

Growth inhibitory response and ultrastructural modification of oral-associated candidal reference strains (ATCC) by Piper betle L. extract.

Science.gov (United States)

Nordin, Mohd-Al-Faisal; Wan Harun, Wan Himratul-Aznita; Abdul Razak, Fathilah; Musa, Md Yusoff

2014-03-01

Candida species have been associated with the emergence of strains resistant to selected antifungal agents. Plant products have been used traditionally as alternative medicine to ease mucosal fungal infections. This study aimed to investigate the effects of Piper betle extract on the growth profile and the ultrastructure of commonly isolated oral candidal cells. The major component of P. betle was identified using liquid chromatography-mass spectrophotometry (LC-MS/MS). Seven ATCC control strains of Candida species were cultured in yeast peptone dextrose broth under four different growth environments: (i) in the absence of P. betle extract; and in the presence of P. betle extract at respective concentrations of (ii) 1 mg⋅mL(-1); (iii) 3 mg⋅mL(-1); and (iv) 6 mg⋅mL(-1). The growth inhibitory responses of the candidal cells were determined based on changes in the specific growth rates (µ). Scanning electron microscopy (SEM) was used to observe any ultrastructural alterations in the candida colonies. LC-MS/MS was performed to validate the presence of bioactive compounds in the extract. Following treatment, it was observed that the µ-values of the treated cells were significantly different than those of the untreated cells (Pbetle extract. The candidal population was also reduced from an average of 13.44×10(6) to 1.78×10(6) viable cell counts (CFU)⋅mL(-1). SEM examination exhibited physical damage and considerable morphological alterations of the treated cells. The compound profile from LC-MS/MS indicated the presence of hydroxybenzoic acid, chavibetol and hydroxychavicol in P. betle extract. The effects of P. betle on candida cells could potentiate its antifungal activity.

Subacute ghrelin administration inhibits apoptosis and improves ultrastructural abnormalities in remote myocardium post-myocardial infarction.

Science.gov (United States)

Eid, Refaat A; Zaki, Mohamed Samir Ahmed; Al-Shraim, Mubarak; Eleawa, Samy M; El-Kott, Attalla Farag; Al-Hashem, Fahaid H; Eldeen, Muhammad Alaa; Ibrahim, Hoja; Aldera, Hussain; Alkhateeb, Mahmoud A

2018-05-01

This study investigated the effect of ghrelin on cardiomyocytes function, apoptosis and ultra-structural alterations of remote myocardium of the left ventricle (LV) of rats, 21 days post myocardial infarction (MI). Rats were divided into 4 groups as a control, a sham-operated rats, a sham-operated+ghrelin, an MI + vehicle and an MI + ghrelin-treated rats. MI was induced by LAD ligation and then rats were recievd a concomitant doe of either normal saline as a vehicle or treated with ghrelin (100 μg/kg S.C., 2x/day) for 21 consecutive days. Ghrelin enhanced myocardial contractility in control rats and reversed the decreases in myocardial contractility and the increases in the serum levels of CK-MB and LDH in MI-induced rats. Additionally, it inhibited the increases in levels of Bax and cleaved caspase 3 and increased those for Bcl-2 in the remote myocardium of rat's LV, post-MI. At ultra-structural level, while ghrelin has no adverse effects on LV myocardium obtained from control or sham-treated rats, ghrelin post-administration to MI-induced rats reduced vascular formation, restored normal microfilaments appearance and organization, preserved mitochondria structure, and prevented mitochondrial swelling, collagen deposition and number of ghost bodies in the remote areas of their LV. Concomitantly, in remote myocardium of MI-induced rats, ghrelin enhanced endoplasmic reticulum intracellular organelles count, decreased number of atrophied nuclei and phagocytes, diminished the irregularity in the nuclear membranes and inhibited chromatin condensation. In conclusion, in addition to the physiological, biochemical and molecular evidence provided, this is the first study that confirms the anti-apoptotic effect of ghrelin in the remote myocardium of the LV during late MI at the level of ultra-structural changes. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

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

Science.gov (United States)

Han, Yun; Zheng, Yan-Li; Wu, Ai-Min; Liu, Hong-Bin; Su, Jian-Bin; Lu, Xiao-Yan; Han, Yu-Wen; Ji, Jin-Long; Ji, Ju-Hua; Shi, Yue

2016-12-01

A great quantity of gestational diabetes mellitus with normal prepregnancy body mass index have emerged with the new criteria of gestational diabetes mellitus in China based on the International Diabetes in Pregnancy Consensus group criteria, and understanding placental changes and how they affect outcomes are necessary in order to develop effective management approach. The aim of this study was to prospectively explore the effect of active management starting from the late second trimester in gestational diabetes mellitus women with normal prepregnancy body mass index on pregnancy outcomes and placental ultrastructures, and to provide scientific evidences for optimizing the management of gestational diabetes mellitus in China. Gestational diabetes mellitus women with normal prepregnancy body mass index in the same period of this prospective cohort study were divided into intervention group (n = 51) and control group (n = 55). The intervention group was managed rigorously, while the control group received conventional prenatal cares. The glucose profile, gestational weight gain and pregnancy outcomes were followed up and placental ultrastructures were observed and recorded by transmission electron microscopy. The blood glucose level and gestational weight gain in intervention group were significantly better controlled than those in control group (P gestational age were significantly lower in intervention group than in control group (P gestational age (P gestational diabetes mellitus women with normal prepregnancy body mass index can improve pregnancy outcomes and placental ultrastructures, and the abnormal placental ultrastructure might be closely associated with the undesirable glycemic control and adverse pregnancy outcomes.

The ultrastructure of chloroplasts in variegata irregulare mutants of garden petunias (Petunia hybrida hort. superbissima

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Stanisław Muszyński

2015-01-01

Full Text Available The ultrastructure of mutated chloroplasts in tetraploid garden petunias (Petunia hybrida hort. superbissima was analyzed by electron microscopy. The formation of grana structure is inhibited after secondary thylacoids start forming. Rapid dezintegration of the structure is observed. It is suggested that a substance responsible for photostabilization of grana structure is lacking.

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

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Caroline Nery Jezler

2015-03-01

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

Ultrastructure Organization of Collagen Fibrils and Proteoglycans of Stingray and Shark Corneal Stroma

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Saud A. Alanazi

2015-01-01

Full Text Available We report here the ultrastructural organization of collagen fibrils (CF and proteoglycans (PGs of the corneal stroma of both the stingray and the shark. Three corneas from three stingrays and three corneas from three sharks were processed for electron microscopy. Tissues were embedded in TAAB 031 resin. The corneal stroma of both the stingray and shark consisted of parallel running lamellae of CFs which were decorated with PGs. In the stingray, the mean area of PGs in the posterior stroma was significantly larger than the PGs of the anterior and middle stroma, whereas, in the shark, the mean area of PGs was similar throughout the stroma. The mean area of PGs of the stingray was significantly larger compared to the PGs, mean area of the shark corneal stroma. The CF diameter of the stingray was significantly smaller compared to the CF diameter in the shark. The ultrastructural features of the corneal stroma of both the stingray and the shark were similar to each other except for the CFs and PGs. The PGs in the stingray and shark might be composed of chondroitin sulfate (CS/dermatan sulfate (DS PGs and these PGs with sutures might contribute to the nonswelling properties of the cornea of the stingray and shark.

Ultrastructure of developing ascospores in Sordaria brevicollis.

Science.gov (United States)

Hackett, C J; Chen, K C

1976-05-01

The ultrastructure of ascospore wall formation in the pyrenomycete Sordaria brevicollis was studied in developing asci at progressive time intervals. From early spore delimitation through final stage of maturation, the wall of the ascospore differentiated into four composite layers, the periascosporium the delineation ascosporium, the subascosproium, and the endoascosproium, While ascospores were at the hyaline stage of development,they possessed only the periascosporium and delineation ascosporium as their wall components. At about 7 to 8 days from the initiation of the cross, the spores developed a yellow color, and this coloration was always associated with the elaboration of the subascorsporium just internal to the ascosporium. Asthe spores continued to progressively darken in color, the subascosporium was seen to increase in complexity, electron density, and thickness. Soon after the formation of the subascosporium, the endoascosporium began to develop de novo and was, therefore, the last wall layer formed as the spore approached maturity.

Alteration in the ultrastructural morphology of mycelial hyphae and the dynamics of transcriptional activity of lytic enzyme genes during basidiomycete morphogenesis.

Science.gov (United States)

Vetchinkina, Elena; Kupryashina, Maria; Gorshkov, Vladimir; Ageeva, Marina; Gogolev, Yuri; Nikitina, Valentina

2017-04-01

The morphogenesis of macromycetes is a complex multilevel process resulting in a set of molecular-genetic, physiological-biochemical, and morphological-ultrastructural changes in the cells. When the xylotrophic basidiomycetes Lentinus edodes, Grifola frondosa, and Ganoderma lucidum were grown on wood waste as the substrate, the ultrastructural morphology of the mycelial hyphal cell walls differed considerably between mycelium and morphostructures. As the macromycetes passed from vegetative to generative development, the expression of the tyr1, tyr2, chi1, chi2, exg1, exg2, and exg3 genes was activated. These genes encode enzymes such as tyrosinase, chitinase, and glucanase, which play essential roles in cell wall growth and morphogenesis.

Ultrastructure of the digestive system of Ramazzottius tribulosus and Macrobiotus richtersi (Eutardigrada in relationship with diet

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Alexandra M. AVDONINA

2007-09-01

Full Text Available The ultrastructure of the digestive system of tardigrades was already described in some species, but it has never been studied in relationship to diet. We performed ultrastructural analyses of the midgut and hindgut of phytophagous Ramazzottius tribulosus and zoophagous Macrobiotus richtersi. In addition, the foregut of R. tribulosus was analyzed. New ultrastructural details have been observed. Among them are: (a distinct transverse pillar-like structures, lacking in electron-dense and compact cuticle of the buccal tube; (b a hole or groups of holes sometimes present in the buccal tube; (c a large cavity within each of the salivary glands where secreted mucus accumulates; and (d already found in zoophagous Isohypsibius prosostomus, one valve, formed by folds of the pharynx and located at the transition from pharynx to esophagus. In both analyzed species the increase of midgut surface is identified by two orders of folds of the gut wall and by microvilli. In R. tribulosus there are many first-order folds and few second-order folds, whereas in M. richtersi the opposite pattern is found. A peritrophic membrane and microvilli with a well developed glycocalyx are found only in the midgut lumen of R. tribulosus. The density of microvilli and the ratio between the real surface with microvilli and the hypothetical surface without microvilli is lower in zoophagous M. richtersi and I. prosostomus than in phytophagous R. tribulosus. All of these data represent an indirect indication of differences in digestive physiology between phytophagous and zoophagous tardigrade species. The shape of the hindgut is similar in both species and the lumen of the hindgut looks like a heartshaped cavity with some narrow cell evaginations.

Photosynthetic, antioxidative, molecular and ultrastructural responses of young cacao plants to Cd toxicity in the soil.

Science.gov (United States)

Pereira de Araújo, Romária; Furtado de Almeida, Alex-Alan; Silva Pereira, Lidiane; Mangabeira, Pedro A O; Olimpio Souza, José; Pirovani, Carlos P; Ahnert, Dário; Baligar, Virupax C

2017-10-01

Cadmium (Cd) is a highly toxic metal for plants, even at low concentrations in the soil. The annual production of world cocoa beans is approximately 4 million tons. Most of these fermented and dried beans are used in the manufacture of chocolate. Recent work has shown that the concentration of Cd in these beans has exceeded the critical level (0.6mgkg -1 DM). The objective of this study was to evaluate the toxicity of Cd in young plants of CCN 51 cacao genotype grown in soil with different concentrations of Cd (0, 0.05 and 0.1gkg -1 soil) through photosynthetic, antioxidative, molecular and ultrastructural changes. The increase of Cd concentration in the soil altered mineral nutrient absorption by competition or synergism, changed photosynthetic activity caused by reduction in chloroplastidic pigment content and damage to the photosynthetic machinery evidenced by the Fv/Fm ratio and expression of the psbA gene and increased GPX activity in the root and SOD in leaves. Additionally, ultrastructural alterations in roots and leaves were also evidenced with the increase of the concentration of Cd in the soil, whose toxicity caused rupture of biomembranes in root and leaf cells, reduction of the number of starch grains in foliar cells, increase of plastoglobules in chloroplasts and presence of multivesiculated bodies in root cells. It was concluded, therefore, that soil Cd toxicity caused damage to the photosynthetic machinery, antioxidative metabolism, gene expression and irreversible damage to root cells ultrastructure of CCN 51 cocoa plants, whose damage intensity depended on the exposure time to the metal. Copyright © 2017. Published by Elsevier Inc.

Effects of ultraviolet radiation and temperature on the ultrastructure of zoospores of the brown macroalga Laminaria hyperborea.

Science.gov (United States)

Steinhoff, F S; Wiencke, C; Müller, R; Bischof, K

2008-05-01

The interactive effects of an 8 h exposure to UV radiation and altered temperatures on the ultrastructure and germination of zoospores of the sublittoral brown alga Laminaria hyperborea (Gunn.) Foslie were investigated for the first time. Spores were exposed to four temperatures (2, 7, 12 and 17 degrees C) and three light regimes (PAR, PAR + UV-A, PAR + UV-A+UV-B). Freshly-released spores of L. hyperborea lack a cell wall and contain a nucleus with fine granular nucleoplasm and a nucleolus, one chloroplast, several mitochondria, dictyosomes and an endoplasmatic reticulum. Further, several kinds of so-called adhesive vesicles, lipid globuli and physodes containing UV-absorbing phlorotannins are embedded in the cytoplasm. No eye-spot is present. Physodes were found but they were rare and small. After an 8 h exposure to UV-B, the nucleoplasm had a mottled structure, chloroplasts contained plastoglobuli, the structure of the mitochondria changed from crista- to sacculus-type and germination was strongly inhibited at all temperatures. UV-A only had an impact on the ultrastructure at the highest temperature tested. The strongest effects were found at 17 degrees C, where germination was reduced to 35%, 32% and 9% after exposure to PAR, PAR+UV-A and PAR + UV-A + UV-B, respectively. This study indicates that UV-B radiation has strong damaging effects on the physiology and ultrastructure of zoospores of L. hyperborea. The results are important for developing scenarios for the effect of enhanced UV radiation and increasing temperatures caused by global climate changes.

The anatomy and ultrastructure of the nectaries and osmophores of water forget-me-not (Myosotis scorpioides L.

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Elżbieta Weryszko-Chmielewska

2014-04-01

Full Text Available Flowers of Myosotis scorpioides L. (Boraginaceae are pollinated by different insects, among others by the honey bee. They produce both secondary attractants (colour, odour and primary attractants which include nectar and pollen. The nectary glands occurring in the flowers form a ring surrounding the base of a superior ovary. The aim of this study was to determine the anatomical characteristics and ultrastructure of the nectary and odour-producing tissues located on the petals. The study was carried out using light, scanning and transmission electron microscopy. The nectary forms a uniform ring surrounding a 4-loculed superior ovary. Nectar is secreted through stomata. The presence of large cell nuclei, numerous plastids and rough endoplasmic reticulum (ER was found in the ultrastructure of the nectary cells. In the parenchyma cells of the nectary, ER was fused to large cisterns (vesicles situated in the marginal parts of the cytoplasm. This study shows that essential oils are emitted through papillae located in the adaxial epidermis of the petals and through large palisade epidermal cells occurring in the yellow region of the corolla, which form the osmophore tissue. The epidermal cells of the osmophore were characterized by the presence of thin cell walls, large nuclei and numerous chromoplasts. Lipid plastoglobules were observed in the chromoplasts; their presence can be associated with the production of essential oils. It was found that the tissues forming the yellow ring at the mouth to the corolla tube (osmophore released a more intense scent than the surface region of the petal on which the papillae occur.

Effect of c-myc on the ultrastructural structure of cochleae in guinea pigs with noise induced hearing loss

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Han, Yu; Zhong, Cuiping [Department of Otolaryngology, Xijing Hospital, Fourth Military Medical University, Xi' an, 710032 Shaanxi Province (China); Hong, Liu [First Division of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi' an, 710032 Shaanxi Province (China); Wang, Ye; Qiao, Li [Department of Otolaryngology, Xijing Hospital, Fourth Military Medical University, Xi' an, 710032 Shaanxi Province (China); Qiu, Jianhua, E-mail: qiujh@fmmu.edu.cn [Department of Otolaryngology, Xijing Hospital, Fourth Military Medical University, Xi' an, 710032 Shaanxi Province (China)

2009-12-18

Noise over-stimulation may induce hair cells loss and hearing deficit. The c-myc oncogene is a major regulator for cell proliferation, growth, and apoptosis. However, the role of this gene in the mammalian cochlea is still unclear. The study was designed to firstly investigate its function under noise condition, from the aspect of cochlear ultrastructural changes. We had established the adenoviral vector of c-myc gene and delivered the adenovirus suspension into the scala tympani of guinea pigs 4 days before noise exposure. The empty adenoviral vectors were injected as control. Then, all subjects were exposed to 4-kHz octave-band noise at 110 dB SPL for 8 h/day, 3 days consecutively. Auditory thresholds were assessed by auditory brainstem response, prior to and 7 days following noise exposure. On the seventh days after noise exposure, the cochlear sensory epithelia surface was observed microscopically and the cochleae were taken to study the ultrastructural changes. The results indicated that auditory threshold shift after noise exposure was higher in the ears treated with Ad.EGFP than that treated with Ad.c-myc-EGFP. Stereocilia loss and the disarrangement of outer hair cells were observed, with greater changes found in the Ad.EGFP group. Also, the ultrastructure changes were severe in the Ad.EGFP group, but not obvious in the Ad.c-myc-EGFP group. Therefore, c-myc gene might play an unexpected role in hearing functional and morphological protection from acoustic trauma.

Effect of c-myc on the ultrastructural structure of cochleae in guinea pigs with noise induced hearing loss

International Nuclear Information System (INIS)

Han, Yu; Zhong, Cuiping; Hong, Liu; Wang, Ye; Qiao, Li; Qiu, Jianhua

2009-01-01

Noise over-stimulation may induce hair cells loss and hearing deficit. The c-myc oncogene is a major regulator for cell proliferation, growth, and apoptosis. However, the role of this gene in the mammalian cochlea is still unclear. The study was designed to firstly investigate its function under noise condition, from the aspect of cochlear ultrastructural changes. We had established the adenoviral vector of c-myc gene and delivered the adenovirus suspension into the scala tympani of guinea pigs 4 days before noise exposure. The empty adenoviral vectors were injected as control. Then, all subjects were exposed to 4-kHz octave-band noise at 110 dB SPL for 8 h/day, 3 days consecutively. Auditory thresholds were assessed by auditory brainstem response, prior to and 7 days following noise exposure. On the seventh days after noise exposure, the cochlear sensory epithelia surface was observed microscopically and the cochleae were taken to study the ultrastructural changes. The results indicated that auditory threshold shift after noise exposure was higher in the ears treated with Ad.EGFP than that treated with Ad.c-myc-EGFP. Stereocilia loss and the disarrangement of outer hair cells were observed, with greater changes found in the Ad.EGFP group. Also, the ultrastructure changes were severe in the Ad.EGFP group, but not obvious in the Ad.c-myc-EGFP group. Therefore, c-myc gene might play an unexpected role in hearing functional and morphological protection from acoustic trauma.

Enzymatic and ultrastructural study of lysosomes in rats bearing radiation-induced thyroid follicular carcinoma

International Nuclear Information System (INIS)

Starling, J.R.; Clifton, K.H.; Norback, D.H.

1981-01-01

Radiation-induced well-differentiated and poorly differentiated follicular thyroid cancers were transplanted into the intrascapular fat pads of male Fisher 144 rats. The tumors grew in the recipient rats and after a time interval were removed and studied along with normal rat thyroids for lysosomal activity and ultrastructural characteristics. Plasma from experimental and control rats was also studied for lysosomal activity. Rats with radiation-induced thyroid carcinoma had a decrease in growth rate compared with normal rats. There was no significant increase in plasma lysosomal enzymes in the experimental rats. Well-differentiated thyroid carcinomatous tissue showed increased total activities of lysosomal enzymes as well as a difference in subcellular distribution compared with normal and poorly differentiated carcinomatous tissue. Electron microscopy of normal and carcinomatous tissue demonstrated the greatest number of lysosomes in the well-differentiated carcinoma and the fewest in the poorly differentiated carcinoma

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

Science.gov (United States)

Dietze, S; Bayerlein, T; Proff, P; Hoffmann, A; Gedrange, T

2006-02-01

The ultrastructure, fundamental chemistry, and processing modes of fully synthetic bone grafting materials are relevant to the reconstruction of osseous defects. Rapid progress in the profitable market of biomaterials has led to the development of various bone substitutes. Despite all these efforts, an ideal and full substitute of autologous bone is not yet in sight. With regard to anorganic calcium phosphate ceramics, Straumann Bone Ceramic and NanoBone are compared. These have a similar composition and are osteoconductive, which indispensably requires contact with well-vascularised bone.

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

International Nuclear Information System (INIS)

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

1988-01-01

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

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

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Selma Majerowicz

1994-09-01

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

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

Science.gov (United States)

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

2012-05-01

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

Ultrastructural localization of human papilloma virus by nonradioactive in situ hybridization on tissue of human cervical intraepithelial neoplasia

DEFF Research Database (Denmark)

Multhaupt, H A; Rafferty, P A; Warhol, M J

1992-01-01

BACKGROUND: A nonradioactive in situ hybridization was developed to localize human papilloma virus (HPV) at the ultrastructural level. EXPERIMENTAL DESIGN: Cervical biopsies from human uterine cervices clinically suspicious of condyloma were embedded in Lowicryl K4M at low temperature...

Experimental nickel-induced pulmonary lesions in nonhuman primates: Histologic and ultrastructural analysis

International Nuclear Information System (INIS)

Haley, P.J.; Bice, D.E.; Muggenburg, B.A.; Hahn, F.F.

1988-01-01

The histologic and ultrastructural alterations of lung were evaluated in cynomolgus monkeys instilled with nickel subsulfide (Ni 3 S 2 ) at a final dose of 0.06 μmol/g lung with and without repeated intrapulmonary exposure to sheep red blood cells (SRBC). individual lung lobes were exposed to nickel alone, SRBC alone, or nickel and SRBC together. Lesions were found in nickel-exposed lobes only, regardless of exposure to SRBC. Lesions were more developed at 14 days than at 21 days after exposure to nickel, and were characterized by multifocal perivascular and peribronchiolar lymphocytic infiltrates along with microgranuloma formation, occasional fibrosis and moderate type II epithelial cell hyperplasia. Microgranulomas consisted of either central histiocytic cores surrounded by lymphocytic mantles or dense aggregates of epithelioid cells forming irregular interstitial nodules. Tracheobronchial lymph nodes had marked reactive hyperplasia of cortical and paracortical zones. Ultrastructural analysis of lung lesions revealed numerous well-differentiated lymphocytes intermixed with macrophages, in a background of mature collagen bundles. Cell associated particles were evaluated by energy dispersive microanalysis and found to consist of nickel and sulfur. These lesions appeared to be distinct from pneumoconiotic lesions induced by inert dusts and had histologic qualities compatible with immune-mediated phenomena. Because nickel compounds stimulate strong humoral and cellular immune responses in man, we conclude that pulmonary exposure of nonhuman primates to nickel compounds may provide information useful in delineating Immune mediated pulmonary disorders of man. (author)

Dietary cadmium and enteropathy in the Japanese quail: histochemical and ultrastructural studies

Energy Technology Data Exchange (ETDEWEB)

Richardson, M.E.; Fox, M.R.S.

1974-01-01

Cadmium was fed to young Japanese quail, at a level of 75 mg. per kg. of diet, from hatching to 4 weeks of age. Cadmium produced gross, microscopic, and ultrastructural lesions in the proximal small intestine of these quail, similar to those occurring in human malabsorption syndromes, celiac disease, nontropical sprue, and tropical sprue. The small intestines of the quail were dilated and thin walled. Villi were short and thick and had a dense cellular infiltrate in the lamina propria. The striated border was thin but stained for neutral mucopolysaccharides, as did the normal border. Some villi were covered with stratified epithelial cells. Hypertrophy and hyperplasia of goblet were seen, but the mucin stained for weakly acidic mucopolysaccharides, as did the normal cells. At the ultrastructural level, microvilli of both absorptive and goblet cells were markedly shortened, particularly near the tips of the villi. Absorptive cells were atrophic, and there was s diminution of the usual cellular organelles. Granular cisternae were long and tortuous, mitochondria were dense and small, and large lysosome-like bodies and large lipid droplets accumulated in the cytoplasm, but there was a decrease in the normal small, pale and dark lipid droplets. The cellular infiltrate of the lamina propria included groups of plasma cells with dilated cisternae. There were large, irregular, electron-dense bodies in the endothelium of large veins and degeneration of some nerve plexuses in the muscularis propria. 31 references, 21 figures.

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

Science.gov (United States)

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

2016-09-01

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

Ultrastructure of the anterior organ and posterior funnel-shaped canal of Gyrocotyle urna Wagener, 1852 (Cestoda: Gyrocotylidea)

Czech Academy of Sciences Publication Activity Database

Poddubnaya, L. G.; Kuchta, Roman; Bristow, G.A.; Scholz, Tomáš

2015-01-01

Roč. 62, 2015 May 22 (2015), 027 ISSN 1803-6465 R&D Projects: GA ČR GBP505/12/G112 Institutional support: RVO:60077344 Keywords : scanning electron microscopy * transmission electron microscopy * basal cestodes * ultrastructural characters * phylogeny Subject RIV: EG - Zoology Impact factor: 1.271, year: 2015

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

Science.gov (United States)

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

1975-01-01

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

High resolution scanning electron microscopy of rabbit corneal endothelium to show effects of UV-visible irradiation in the presence of chlorpromazine

Energy Technology Data Exchange (ETDEWEB)

Lea, P.J.; Hollenberg, M.J.; Menon, I.A.; Temkin, R.J.; Persad, S.D.; Basu, P.K. (Univ. of Toronto, Ontario (Canada))

1989-01-01

The ultrastructure of rabbit cornea endothelial cells was examined by scanning electron microscopy (SEM) in freeze-cleaved corneas using a Hitachi S-570 scanning electron microscope in the high resolution mode (HRSEM). In order to study phototoxic effects in vitro, rabbit corneas (experimental) were cultured as organ culture in the presence of 5 micrograms/ml chlorpromazine (CPZ) and irradiated. For comparison, control 1 corneas were not irradiated but incubated in the dark without CPZ in the medium; control 2 corneas were also kept in the dark but in the presence of CPZ; control 3 corneas were irradiated with no CPZ in the medium. Cellular damage was not seen in the three types of control corneas, but in the experimental corneas the endothelial cells showed extensive disruption of the cell membrane and some deterioration of the intracellular components. Our study confirmed that HRSEM is a satisfactory new technique for visualizing damage of the intracellular organelles of corneal endothelium.

High resolution scanning electron microscopy of rabbit corneal endothelium to show effects of UV-visible irradiation in the presence of chlorpromazine

International Nuclear Information System (INIS)

Lea, P.J.; Hollenberg, M.J.; Menon, I.A.; Temkin, R.J.; Persad, S.D.; Basu, P.K.

1989-01-01

The ultrastructure of rabbit cornea endothelial cells was examined by scanning electron microscopy (SEM) in freeze-cleaved corneas using a Hitachi S-570 scanning electron microscope in the high resolution mode (HRSEM). In order to study phototoxic effects in vitro, rabbit corneas (experimental) were cultured as organ culture in the presence of 5 micrograms/ml chlorpromazine (CPZ) and irradiated. For comparison, control 1 corneas were not irradiated but incubated in the dark without CPZ in the medium; control 2 corneas were also kept in the dark but in the presence of CPZ; control 3 corneas were irradiated with no CPZ in the medium. Cellular damage was not seen in the three types of control corneas, but in the experimental corneas the endothelial cells showed extensive disruption of the cell membrane and some deterioration of the intracellular components. Our study confirmed that HRSEM is a satisfactory new technique for visualizing damage of the intracellular organelles of corneal endothelium

Ultrastructural biomarkers in symbiotic algae reflect the availability of dissolved inorganic nutrients and particulate food to the reef coral holobiont

Directory of Open Access Journals (Sweden)

Sabrina eRosset

2015-11-01

Full Text Available Reef building corals associated with symbiotic algae (zooxanthellae can access environmental nutrients from different sources, most significantly via the uptake of dissolved inorganic nutrients by the algal symbiont and heterotrophic feeding of the coral host. Climate change is expected to alter the nutrient environment in coral reefs with the potential to benefit or disturb coral reef resilience. At present, the relative importance of the two major nutrient sources is not well understood, making predictions of the responses of corals to changes in their nutrient environment difficult. Therefore, we have examined the long-term effects of the availability of different concentrations of dissolved inorganic nutrients and of nutrients in particulate organic form on the model coral Euphyllia paradivisa. Coral and algal biomass showed a significantly stronger increase in response to elevated levels of dissolved inorganic nutrients as compared to the supply with particulate food. Also, changes in the zooxanthellae ultrastructure, determined by transmission electron microscopy (TEM, were mostly driven by the availability of dissolved inorganic nutrients under the present experimental conditions. The larger size of symbiont cells, their increased accumulation of lipid bodies, a higher number of starch granules and the fragmentation of their accumulation body could be established as reliable biomarkers of low availability of dissolved inorganic nutrients to the coral holobiont.

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

Science.gov (United States)

Rabaey, David; Lens, Frederic; Huysmans, Suzy; Smets, Erik; Jansen, Steven

2008-11-01

Recent micromorphological observations of angiosperm pit membranes have extended the number and range of taxa with pseudo-tori in tracheary elements. This study investigates at ultrastructural level (TEM) the development of pseudo-tori in the unrelated Malus yunnanensis, Ligustrum vulgare, Pittosporum tenuifolium, and Vaccinium myrtillus in order to determine whether these plasmodesmata associated thickenings have a similar developmental pattern across flowering plants. At early ontogenetic stages, the formation of a primary thickening was observed, resulting from swelling of the pit membrane in fibre-tracheids and vessel elements. Since plasmodesmata appear to be frequently, but not always, associated with these primary pit membrane thickenings, it remains unclear which ultrastructural characteristics control the formation of pseudo-tori. At a very late stage during xylem differentiation, a secondary thickening is deposited on the primary pit membrane thickening. Plasmodesmata are always associated with pseudo-tori at these final developmental stages. After autolysis, the secondary thickening becomes electron-dense and persistent, while the primary thickening turns transparent and partially or entirely dissolves. The developmental patterns observed in the species studied are similar and agree with former ontogenetic studies in Rosaceae, suggesting that pseudo-tori might be homologous features across angiosperms.

Assessment of nerve ultrastructure by fibre-optic confocal microscopy.

Science.gov (United States)

Cushway, T R; Lanzetta, M; Cox, G; Trickett, R; Owen, E R

1996-01-01

Fibre-optic technology combined with confocality produces a microscope capable of optical thin sectioning. In this original study, tibial nerves have been stained in a rat model with a vital dye, 4-(4-diethylaminostyryl)-N-methylpyridinium iodide, and analysed by fibre-optic confocal microscopy to produce detailed images of nerve ultrastructure. Schwann cells, nodes of Ranvier and longitudinal myelinated sheaths enclosing axons were clearly visible. Single axons appeared as brightly staining longitudinal structures. This allowed easy tracing of multiple signal axons within the nerve tissue. An accurate measurement of internodal lengths was easily accomplished. This technique is comparable to current histological techniques, but does not require biopsy, thin sectioning or tissue fixing. This study offers a standard for further in vivo microscopy, including the possibility of monitoring the progression of nerve regeneration following microsurgical neurorraphy.

Morphology and Ultrastructure of Multiple Life Cycle Stages of the Photosynthetic Relative of Apicomplexa, Chromera velia

Czech Academy of Sciences Publication Activity Database

Oborník, Miroslav; Vancová, Marie; Lai, De Hua; Janouškovec, J.; Keeling, P. J.; Lukeš, Julius

2011-01-01

Roč. 162, č. 1 (2011), s. 115-130 ISSN 1434-4610 R&D Projects: GA AV ČR IAA601410907; GA MŠk 2B06129; GA MŠk LC07032 Institutional research plan: CEZ:AV0Z60220518 Keywords : Chromera * Apicomplexa * Colpodella * dinoflagellate * phylogeny * ultrastructure Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.136, year: 2011

Ultrastructural investigations of meiosis as a tool in assessing radiation damage in man

Energy Technology Data Exchange (ETDEWEB)

Bojko, M.

1985-01-01

Part I is an introduction to the problems of assessing the short-term effects of ionizing radiation on human meiosis. Part II is an investigation of the ultrastructure of human oocytes at pachytene and diplotene stages of meiotic prophase. Processes leading to crossing over and chiasma formation in the female are compared with those in the male and in other organisms. Part III is a study of short-term effects of ..gamma.. radiation on spermatocytes in larvae of the silk moth, Bombyx mori.

Ultrastructural Analysis of Urinary Stones by Microfocus Computed Tomography and Comparison with Chemical Analysis

Directory of Open Access Journals (Sweden)

Tolga Karakan

2016-06-01

Full Text Available Objective: To investigate the ultra-structure of urinary system stones using micro-focus computed tomography (MCT, which makes non-destructive analysis and to compare with wet chemical analysis. Methods: This study was carried out at the Ankara Train­ing and Research hospital. Renal stones, removed from 30 patients during percutaneous nephrolithotomy (PNL surgery, were included in the study. The stones were blindly evaluated by the specialists with MCT and chemi­cal analysis. Results: The comparison of the stone components be­tween chemical analysis and MCT, showed that the rate of consistence was very low (p0.05. It was also seen that there was no significant relation between its 3D structure being heterogeneous or homogenous. Conclusion: The stone analysis with MCT is a time con­suming and costly method. This method is useful to un­derstand the mechanisms of stone formation and an im­portant guide to develop the future treatment modalities.

Ultrastructure of the extracellular matrix of bovine dura mater, optic nerve sheath and sclera.

OpenAIRE

Raspanti, M; Marchini, M; Della Pasqua, V; Strocchi, R; Ruggeri, A

1992-01-01

The sclera, the outermost sheath of the optic nerve and the dura mater have been investigated histologically and ultrastructurally. Although these tissues appear very similar under the light microscope, being dense connective tissues mainly composed of collagen bundles and a limited amount of cells and elastic fibres, they exhibit subtle differences on electron microscopy. In the dura and sclera collagen appears in the form of large, nonuniform fibrils, similar to those commonly found in tend...

ARG3.1/ARC expression in hippocampal dentate gyrus astrocytes: ultrastructural evidence and co-localization with glial fibrillary acidic protein

Czech Academy of Sciences Publication Activity Database

Rodríguez, J.J.; Davies, H.A.; Errington, M.L.; Verkhratsky, Alexei; Bliss, T.V.P.; Stewart, M.G.

2008-01-01

Roč. 12, č. 2 (2008), s. 671-678 ISSN 1582-1838 Institutional research plan: CEZ:AV0Z50390512 Keywords : Hippocampus * Ultrastructure * Glia Subject RIV: FH - Neurology Impact factor: 5.114, year: 2008

BIOSECURITY FOR REDUCING OCHRATOXIN A PRODUCTIVITY AND THEIR IMPACT ON GERMINATION AND ULTRASTRUCTURES OF GERMINATED WHEAT GRAINS

Directory of Open Access Journals (Sweden)

M.M.

2012-08-01

Full Text Available Ochratoxin A (OTA is a secondary metabolite of some fungi that causes very serious problems for plants, animals and humans. Various microorganisms such as bacteria and microscopic fungi have been tested for their abilities to prevent ochratoxin A contamination or detoxify foods. In this study, Saccharomyces cerevisiae and Lactobacillus bulgaricus reduced OTA production by Aspergillus ochraceus to 40.88 µg/ml ( productivity 60.69% and 13.80 µg/ml (productivity 20.48% respectively compared with the control (67.35 µg/ml (productivity 100%. The results clearly indicated that the seed germinibility in the presence of OTA was decreased with increasing concentration, whereas the germinibility was uncompletely ceased at high concentration (67.35 µg/ml of OTA. The maximum amount of germination was observed in control (without OTA treatment and at low concentration (13.80 µg/ml within 4 days. Antioxidant enzymes catalase and peroxidase decreased in germinated grains treated with OTA. Catalase was 18.12 U/ml in grains treated with low concentration (13.80 µg/ml of OTA while at high concentration (67.35 µg/ml, it was 12.23 U/ml compared with the control (20.33 U/ml. On the other hand, peroxidase decreased only in germinated grains treated with high concentration of OTA. The ultrastructural studies indicate that there were dramatic differences between the cells of root system of wheat seedlings of grains treated and untreated with the OTA. Cell ultrastructures of treated grains with OTA showed that the cytoplasmic membrane collapses away from the cell wall. Plasmodesmata threads were appeared in untreated cells but not formed in treated cells.

Ultrastructural changes of central nervous system irradiated with ionizing radiation

Energy Technology Data Exchange (ETDEWEB)

Kimura, Y [Keio Univ., Tokyo (Japan). School of Medicine

1975-12-01

Morphological changes of the central nervous tissues (cerebral and cerebellar cortices) of mice which were irradiated by a massive dose (5,000-80,000 rad) of Linac x-ray were observed with the lapse of time by electron microscopy, and changes in their ultrastructure were investigated. Capillaries and the processes of astrocytes surrounding them, when irradiated with 5,000-40,000 rad, showed swelling of endothelial cells, nuclear atrophy, destruction of basement membrane, and swelling and edematous changes of astrocytic processes. Morphological changes of the nerve cells, granule cells of cerebellum, and astrocytes increased depending on the dose of irradiation, and their injuries appeared in the early stage, showing pyknosis, chromatokinesis, and turbid swelling, transparent swelling of mitochondria, and disappearance of Nissl's bodies as cytoplasmic changes. Destruction of cell membrane was observed in the cerebellar granule cells and astrocytes; particularly in the cerebellar granule cells, pyknosis and prominent degeneration of cytoplasm appeared very early, compared with other cells. Although no definite change nor severance was observed in the marrow sheath of medullated nerve fibers within the dose range of this study, an image of degeneration was observed in the mitochondria in the axon; splitting of marrow sheath and deformity of axon membrane were more prominent in the 40,000 rad-irradiated group than in the other groups. Synaptic vesicles tended to increase and scatter when irradiated with 5,000 rad and 10,000 rad. However, by the irradiation with 40,000 rad, the synaptic vesicles tended to enlarge and decrease on the contrary, disappearing with the lapse of time.

Radioprotective Effect of Lidocaine on Function and Ultrastructure of Salivary Glands Receiving Fractionated Radiation

Energy Technology Data Exchange (ETDEWEB)

Hakim, Samer George, E-mail: samer.hakim@mkg-chir.mu-luebeck.de [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany); Benedek, Geza Attila [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany); Su Yuxiong [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany); Department of Oral and Maxillofacial Surgery, Sun Yat-Sen University, Guanghua School of Stomatology, Guanghua (China); Jacobsen, Hans Christian [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany); Klinger, Matthias [Institute of Anatomy, University of Luebeck, Luebeck (Germany); Dendorfer, Andreas [Institute of Experimental and Clinical Pharmacology and Toxicology, University of Luebeck, Luebeck (Germany); Hemmelmann, Claudia [Institute of Medical Biometry and Statistics, University of Luebeck, Luebeck (Germany); Meller, Birgit [Department of Radiology and Nuclear Medicine, University of Luebeck, Luebeck (Germany); Nadrowitz, Roger; Rades, Dirk [Department of Radiation Oncology, University of Luebeck, Luebeck (Germany); Sieg, Peter [Department of Oral and Maxillofacial Surgery, University of Luebeck, Luebeck (Germany)

2012-03-15

Purpose: Radiation-induced xerostomia still represents a common side effect after radiotherapy for head-and-neck malignancies. The aim of the present study was to examine the radioprotective effect of lidocaine hydrochloride during fractionated radiation in an experimental animal model. Methods and Materials: To evaluate the influence of different radiation doses on salivary gland function and the radioprotective effect of lidocaine, rabbits were irradiated with 15, 25, 30, and 35 Gy (equivalent doses in 2-Gy fractions equivalent to 24, 40, 48, and 56 Gy, respectively). Lidocaine hydrochloride (10 and 12 mg/kg) was administered before every radiation fraction in the treatment groups. Salivary gland function was assessed by flow sialometry and sialoscintigraphy, and the morphologic changes were evaluated using transmission electron microscopy. Results: Functional impairment was first observed after 35 Gy and pretreatment with lidocaine improved radiation tolerance of both parotid and submandibular glands. The use of 12 mg/kg lidocaine was superior and displayed significant radioprotection with regard to flow sialometry and sialoscintigraphy. The ultrastructure was largely preserved after pretreatment with both lidocaine doses. Conclusions: Lidocaine represents an effective radioprotective agent and a promising approach for clinical application to avoid radiation-induced functional impairment of salivary glands.

Radioprotective Effect of Lidocaine on Function and Ultrastructure of Salivary Glands Receiving Fractionated Radiation

International Nuclear Information System (INIS)

Hakim, Samer George; Benedek, Gèza Attila; Su Yuxiong; Jacobsen, Hans Christian; Klinger, Matthias; Dendorfer, Andreas; Hemmelmann, Claudia; Meller, Birgit; Nadrowitz, Roger; Rades, Dirk; Sieg, Peter

2012-01-01

Purpose: Radiation-induced xerostomia still represents a common side effect after radiotherapy for head-and-neck malignancies. The aim of the present study was to examine the radioprotective effect of lidocaine hydrochloride during fractionated radiation in an experimental animal model. Methods and Materials: To evaluate the influence of different radiation doses on salivary gland function and the radioprotective effect of lidocaine, rabbits were irradiated with 15, 25, 30, and 35 Gy (equivalent doses in 2-Gy fractions equivalent to 24, 40, 48, and 56 Gy, respectively). Lidocaine hydrochloride (10 and 12 mg/kg) was administered before every radiation fraction in the treatment groups. Salivary gland function was assessed by flow sialometry and sialoscintigraphy, and the morphologic changes were evaluated using transmission electron microscopy. Results: Functional impairment was first observed after 35 Gy and pretreatment with lidocaine improved radiation tolerance of both parotid and submandibular glands. The use of 12 mg/kg lidocaine was superior and displayed significant radioprotection with regard to flow sialometry and sialoscintigraphy. The ultrastructure was largely preserved after pretreatment with both lidocaine doses. Conclusions: Lidocaine represents an effective radioprotective agent and a promising approach for clinical application to avoid radiation-induced functional impairment of salivary glands.

Ultrastructural examination of lead localisation in germinating seeds of Raphanus sativus

Energy Technology Data Exchange (ETDEWEB)

Lane, S.D.; Martin, E.S.

1982-07-01

Transmission electron microscopy of lead-contaminated germinating seeds has revealed that major sites of lead deposition exist within the cell wall and in association with spherosome-like vesicles common in all cells. There was also evidence of contamination of the plasmalemma, vacuole and subsequently the nucleus. In general radicle and hypocotyl tissue showed more extensive contamination than the cotyledons. The observations are discussed in relation to cell structure and development.

Accumulation of enriched uranium UO2F2 in ultrastructure as studied by electron microscopic autoradiography

International Nuclear Information System (INIS)

Zhu Shoupeng; Wang Yuanchang

1992-01-01

A study was made on the retention of soluble enriched uranium UO 2 F 2 in ultrastructure by electron microscopic autoradiography. The early dynamic accumulation of radioactivity in the body showed that enriched uranium UO 2 F 2 was mainly localized in kidneys, especially accumulated in epithelial cells of proximal convoluted tubules leading to degeneration and necrosis of the tubules. In liver cells, enriched uranium UO 2 F 2 at first deposited in nuclei of the cells and in soluble proteins of the plasma, and later accumulated selectively in mitochondria and lysosomes. On electron microscopic autoradiographic study it was shown that the dynamic retention of radioactivity of enriched uranium UO 2 F 2 in skeleton increased steadily through the time period of exposure. Enriched uranium UO 2 F 2 chiefly deposited in nuclei and mitochondria of osteoblasts as well as of osteoclasts

Ultrastructural investigations of meiosis as a tool in assessing radiation damage in man

International Nuclear Information System (INIS)

Bojko, M.

1985-11-01

Part I is an introduction to the problems of assesing the short-term effects of ionizing radiation on human meiosis. Part II is an investigation of the ultrastructure of human oocytes at pachytene and diplotene stages of meiotic prophase. Processes leading to crossing over and chiasma formation in the female are compared with those in the male and in other organisms. Part III is a study of short-term effects of γ radiation on spermatocytes in larvae of the silk moth, Bombyx mori. (eg)

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

Directory of Open Access Journals (Sweden)

David B. Rivers

2011-01-01

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

Congenital dyserythropoiesis with intererythroblastic chromatin bridges and ultrastructurally-normal erythroblast heterochromatin: a new disorder.

Science.gov (United States)

Wickramasinghe, S N; Spearing, R L; Hill, G R

1998-12-01

Two non-anaemic subjects, a father and daughter, with a new form of congenital dyserythropoiesis are reported. The features of their disorder are: (1) an abnormal blood film with basophilic stippling of red cells and oval macrocytes, (2) various dysplastic changes in the erythroblasts, including internuclear chromatin bridges, (3) ultrastructurally-normal erythroblast heterochromatin, (4) normal serum thymidine kinase activity, and (5) a probable autosomal dominant inheritance. The last three features distinguish this disorder from CDA type I.

Ultrastructural characteristics of type A epithelioid cells during BCG-granulomatosis and treatment with lysosomotropic isoniazid.

Science.gov (United States)

Shkurupii, V A; Kozyaev, M A; Nadeev, A P

2006-04-01

We studied BCG-granulomas, their cellular composition, and ultrastructure of type A epithelioid cells in the liver of male BALB/c mice with spontaneous granulomatous inflammation. The animals received free isoniazid or isoniazid conjugated with lysosomotropic intracellularly prolonged matrix (dialdehyde dextran, molecular weight 65-75 kDa). Lysosomotropic isoniazid was accumulated in the vacuolar apparatus of epithelioid cells and produced a stimulatory effect on plastic processes in these cells.

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

OpenAIRE

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

2017-01-01

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

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

Science.gov (United States)

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

Biochemical and ultrastructural changes in rabbit sclera after treatment with 7-methylxanthine, theobromine, acetazolamide, or L-ornithine

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Trier, K.; Olsen, E. B.; Kobayashi, T.; Ribel-Madsen, S. M.

1999-01-01

AIMS—To examine a possible effect of 7-methylxanthine, theobromine, acetazolamide, or L-ornithine on the ultrastructure and biochemical composition of rabbit sclera.
METHODS—Groups of pigmented rabbits, six in each group, were dosed during 10 weeks with one of the substances under investigation, and one untreated group was the control. Samples of anterior and posterior sclera were taken for determination of hydroxyproline, hydroxylysine, proline, proteoglycans, uronic acids and dermatan sulphate, chondroitin sulphate, and hyaluronic acid. Sections were examined with electron microscopy, and the diameter of the individual collagen fibrils was measured.
RESULTS—Treatment with theobromine produced a significant increase in the contents of hydroxylysine, hydroxyproline, and proline in both anterior and posterior sclera, while 7-methylxanthine increased the contents of hydroxyproline and proline selectively in posterior sclera. Acetazolamide, on the other hand, significantly decreased the contents of hydroxyproline and proline in samples from anterior sclera. Uronic acids in both anterior and posterior sclera were significantly reduced by treatment with 7-methylxanthine, and L-ornithine significantly reduced uronic acids in posterior sclera. An inverse correlation between contents of hydroxyproline and uronic acids was found. The mean diameter of collagen fibrils was significantly higher in the posterior sclera from rabbits treated with 7-methylxanthine or theobromine, and significantly lower in rabbits treated with acetazolamide or L-ornithine compared with controls. In the anterior sclera, fibril diameter was significantly reduced in all treatment groups compared with controls. A positive, significant correlation between fibril diameter and content of hydroxyproline and proline was found in posterior sclera.
CONCLUSION—7-Methylxanthine, a metabolite of caffeine, increases collagen concentration and the diameter of collagen fibrils in the posterior

Ultrastructure of the midgut endocrine cells in Melipona quadrifasciata anthidioides (Hymenoptera, Apidae

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C. A. Neves

Full Text Available In this study we describe the ultrastructure of the endocrine cells observed in the midgut of M. quadrifasciata anthidioides. This bee has two types of endocrine cells, which are numerous on the posterior midgut region. Cells of the closed type are smaller and have irregular secretory granules with lower electrondensity than those of the open cell type. The open cell type has elongated mitochondria mainly on the basal area, where most of the secretory granules are also found. Besides the secretion granules and mitochondria, endocrine cells in this species have well-developed autophagic vacuoles and Golgi complex elements.

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

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

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

Lack of correlation between immunologic markers and cell surface ultrastructure in the leukemic phase of lymphoproliferative diseases

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Golomb, Harvey M.; Simon, Deberah

1977-01-01

In a prospective study of malignant cells from 13 patients with the leukemic phase of lymphoproliferative diseases, we wished to determine whether any correlation between the immunologic markers and the cell surface ultrastructure. Five patients had chronic lymphocytic leukemia, four had malignant lymphomas, poorly differentiated lymphocytic type, two had the Sezary syndrome, and one each had acute prolymphocytic leukemia and acute lymphocytic leukemia. Cell separation and isolation was done at room temperature for all specimens. Immunologic markers tested for were surface immunoglobins, a B-cell property, and E-rosettes, a T-cell property. Three patients had T-cell diseases, 6 had B-cell diseases, and 4 were classified as ''null.'' All but one patient had moderate to large numbers of microvilli on their malignant cells. The single exception had a typical B-cell form of chronic lymphocytic leukemia. There appears to be no correlation between immunologic markers and cell surface ultrastructure; therefore, SEM appears not to be valuable in the diagnosis or classification of immunologic sub-types of certain lymphoproliferative diseases.

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

KAUST Repository

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

2012-01-01

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

GEITLERINEMA SPECIES (OSCILLATORIALES, CYANOBACTERIA) REVEALED BY CELLULAR MORPHOLOGY, ULTRASTRUCTURE, AND DNA SEQUENCING(1).

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Do Carmo Bittencourt-Oliveira, Maria; Do Nascimento Moura, Ariadne; De Oliveira, Mariana Cabral; Sidnei Massola, Nelson

2009-06-01

Geitlerinema amphibium (C. Agardh ex Gomont) Anagn. and G. unigranulatum (Rama N. Singh) Komárek et M. T. P. Azevedo are morphologically close species with characteristics frequently overlapping. Ten strains of Geitlerinema (six of G. amphibium and four of G. unigranulatum) were analyzed by DNA sequencing and transmission electronic and optical microscopy. Among the investigated strains, the two species were not separated with respect to cellular dimensions, and cellular width was the most varying characteristic. The number and localization of granules, as well as other ultrastructural characteristics, did not provide a means to discriminate between the two species. The two species were not separated either by geography or environment. These results were further corroborated by the analysis of the cpcB-cpcA intergenic spacer (PC-IGS) sequences. Given the fact that morphology is very uniform, plus the coexistence of these populations in the same habitat, it would be nearly impossible to distinguish between them in nature. On the other hand, two of the analyzed strains were distinct from all others based on the PC-IGS sequences, in spite of their morphological similarity. PC-IGS sequences indicate that these two strains could be a different species of Geitlerinema. Using morphology, cell ultrastructure, and PC-IGS sequences, it is not possible to distinguish G. amphibium and G. unigranulatum. Therefore, they should be treated as one species, G. unigranulatum as a synonym of G. amphibium. © 2009 Phycological Society of America.

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

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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.

Achados anatomo-patológicos e ultraestruturais na mucopoussacaridose: relato de caso Anatomo-pathological and ultrastructural features in mucopolysaccharidosis: case report

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Luiz Fernando Bleggi Torres

1997-01-01

Full Text Available As mucopolissacaridoses (MPS são doenças de acúmulo lisossomal em que ocorre defeito enzimático específico com consequente acúmulo de glicosaminoglicanos nos tecidos. Os autores relatam o caso de necrópsia de paciente do sexo masculino, com 10 anos de idade, com diagnóstico clínico e laboratorial de MPS. O exame de necrópsia revelou espessamento acentuado de meninges e das valvas cardíacas e hepatomegalia. O exame microscópico do encéfalo evidenciou acúmulo de histiócitos espumosos ao redor dos vasos e nas meninges, assim como neurônios contendo material citoplasmático condizente com gangliosídeo. Alterações sistêmicas como acúmulo de histiócitos espumosos em valvas cardíacas e fígado também foram evidenciados. O exame ultra-estrutural do encéfalo, fígado e baço demonstrou acúmulo de material grumoso no interior de vacúolos em histiócitos e hepatócitos, além de acúmulo de gangliosídeo nos neurônios.The mucopolysaccharidoses (MPS are lysosomal storage diseases in which a specific enzyme defect causes glycosaminoglicans storage in tissues. The authors present a necropsy case of a 10 years old boy with clinical and laboratorial diagnosis of MPS. The necropsy revealed thickening of meninges, cardiac valves and hepatomegaly. The microscopical examination of the brain showed finely vacuolated histiocytes around blood vessels and meninges. Systemic deposits of vacuolated histiocytes in cardiac valves and liver were also detected. The ultrastructural examination of the brain, liver and spleen showed filamentous material accumulated in vacuolated histiocytes and hepatocytes and features neuronal storage disease.

Morphogenesis of Pestiviruses: New Insights from Ultrastructural Studies of Strain Giraffe-1

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Mast, Jan; Thiel, Heinz-Jürgen; König, Matthias

2014-01-01

Knowledge on the morphogenesis of pestiviruses is limited due to low virus production in infected cells. In order to localize virion morphogenesis and replication sites of pestiviruses and to examine intracellular virion transport, a cell culture model was established to facilitate ultrastructural studies. Based on results of virus growth kinetic analysis and quantification of viral RNA, pestivirus strain Giraffe-1 turned out to be a suitable candidate for studies on virion generation and export from culture cells. Using conventional transmission electron microscopy and single-tilt electron tomography, we found virions located predominately in the lumen of the endoplasmic reticulum (ER) in infected cells and were able to depict the budding process of virions at ER membranes. Colocalization of the viral core protein and the envelope glycoprotein E2 with the ER marker protein disulfide isomerase (PDI) was demonstrated by immunogold labeling of cryosections. Moreover, pestivirions could be shown in transport vesicles and the Golgi complex and during exocytosis. Interestingly, viral capsid protein and double-stranded RNA (dsRNA) were detected in multivesicular bodies (MVBs), which implies that the endosomal compartment plays a role in pestiviral replication. Significant cellular membrane alterations such as those described for members of the Flavivirus and Hepacivirus genera were not found. Based on the gained morphological data, we present a consistent model of pestivirus morphogenesis. PMID:24352462

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

Science.gov (United States)

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.

Enamel ultrastructure in fossil cetaceans (Cetacea: Archaeoceti and Odontoceti.

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Carolina Loch

Full Text Available The transition from terrestrial ancestry to a fully pelagic life profoundly altered the body systems of cetaceans, with extreme morphological changes in the skull and feeding apparatus. The Oligocene Epoch was a crucial time in the evolution of cetaceans when the ancestors of modern whales and dolphins (Neoceti underwent major diversification, but details of dental structure and evolution are poorly known for the archaeocete-neocete transition. We report the morphology of teeth and ultrastructure of enamel in archaeocetes, and fossil platanistoids and delphinoids, ranging from late Oligocene (Waitaki Valley, New Zealand to Pliocene (Caldera, Chile. Teeth were embedded in epoxy resin, sectioned in cross and longitudinal planes, polished, etched, and coated with gold palladium for scanning electron microscopy (SEM observation. SEM images showed that in archaeocetes, squalodontids and Prosqualodon (taxa with heterodont and nonpolydont/limited polydont teeth, the inner enamel was organized in Hunter-Schreger bands (HSB with an outer layer of radial enamel. This is a common pattern in most large-bodied mammals and it is regarded as a biomechanical adaptation related to food processing and crack resistance. Fossil Otekaikea sp. and delphinoids, which were polydont and homodont, showed a simpler structure, with inner radial and outer prismless enamel. Radial enamel is regarded as more wear-resistant and has been retained in several mammalian taxa in which opposing tooth surfaces slide over each other. These observations suggest that the transition from a heterodont and nonpolydont/limited polydont dentition in archaeocetes and early odontocetes, to homodont and polydont teeth in crownward odontocetes, was also linked to a marked simplification in the enamel Schmelzmuster. These patterns probably reflect functional shifts in food processing from shear-and-mastication in archaeocetes and early odontocetes, to pierce-and-grasp occlusion in crownward

Enamel ultrastructure in fossil cetaceans (Cetacea: Archaeoceti and Odontoceti).

Science.gov (United States)

Loch, Carolina; Kieser, Jules A; Fordyce, R Ewan

2015-01-01

The transition from terrestrial ancestry to a fully pelagic life profoundly altered the body systems of cetaceans, with extreme morphological changes in the skull and feeding apparatus. The Oligocene Epoch was a crucial time in the evolution of cetaceans when the ancestors of modern whales and dolphins (Neoceti) underwent major diversification, but details of dental structure and evolution are poorly known for the archaeocete-neocete transition. We report the morphology of teeth and ultrastructure of enamel in archaeocetes, and fossil platanistoids and delphinoids, ranging from late Oligocene (Waitaki Valley, New Zealand) to Pliocene (Caldera, Chile). Teeth were embedded in epoxy resin, sectioned in cross and longitudinal planes, polished, etched, and coated with gold palladium for scanning electron microscopy (SEM) observation. SEM images showed that in archaeocetes, squalodontids and Prosqualodon (taxa with heterodont and nonpolydont/limited polydont teeth), the inner enamel was organized in Hunter-Schreger bands (HSB) with an outer layer of radial enamel. This is a common pattern in most large-bodied mammals and it is regarded as a biomechanical adaptation related to food processing and crack resistance. Fossil Otekaikea sp. and delphinoids, which were polydont and homodont, showed a simpler structure, with inner radial and outer prismless enamel. Radial enamel is regarded as more wear-resistant and has been retained in several mammalian taxa in which opposing tooth surfaces slide over each other. These observations suggest that the transition from a heterodont and nonpolydont/limited polydont dentition in archaeocetes and early odontocetes, to homodont and polydont teeth in crownward odontocetes, was also linked to a marked simplification in the enamel Schmelzmuster. These patterns probably reflect functional shifts in food processing from shear-and-mastication in archaeocetes and early odontocetes, to pierce-and-grasp occlusion in crownward odontocetes, with

Ultrastructural aspects of the oesophageal and reproductive systems of the equine parasite Strongylus vulgaris.

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Mobarak, M S; Ryan, M F

2002-06-01

The ultrastructure of the dorsal oesophageal gland ampulla and its relationship with the oesophagus, oesophageal ultrastructure, and control mechanisms in oesophageal activity were studied. Terminal ducts of the sub-ventral glands open through the oesophageal crown at the base of the buccal cavity. The terminal duct of the dorsal oesophageal gland running through the dorsal gutter opens to the exterior at the rim 'groove' of the buccal capsule. The posterior oesophageal region is clavate and the cuticle of the lumen folds to form outlet valves, 'valvulae'. An inconspicuous oesophago-intestinal valve (three lobes) connects oesophagus and intestine and is visualized in the open and shut position. In the female reproductive tract, with the exception of the uterus, the cells lie on a thick, irregular (convoluted) basal lamina. The apical plasma membrane of the uterus, and seminal receptacle, extend into the lumen by microvilli-like projections with which spermatozoa make intimate contact. The lumen of the uterus is filled with oocytes, fertilized and unfertilized. Testicular cells have two parts linked by a rachis. Spermatocytes are elongated with a large nucleus, distinct nuclear membrane, and many granules. The apical membrane of the rachis forms long microvilli-like projections with balloon-like tips. The amoeboid spermatozoa contain membrane specializations, a nucleus devoid of a membrane, and are enclosed by a pseudopodial-like extension.

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

International Nuclear Information System (INIS)

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

2017-01-01

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

Effects of irradiation on epidermis ultrastructure of fresh day-lily flowers

International Nuclear Information System (INIS)

Yang, M.-S.; Chyau, C.-C.; Horng, D.-T.; Yang, J.-S.

2002-01-01

Effects of gamma irradiation on epidermis ultrastructure of fresh day-lily (Hemerocallis fulva L.) flowers were studied by scanning electron microscopy. Damaged cells of petal epidermis were found in the day-lily flowers irradiated with 1.0 or more kGy. The cells damaged by irradiation broke and lost cytoplasm, and therefore, showed a serious shrinkage. The compartment of the cells disappeared in injury. With 1.0 or more kGy irradiation, the damaged cells were also observed on the epidermis of the sepal and receptacle cells. The injury was found in a small spot or area on the epidermis of the sepal as well as the petal. The injury spot of the sepal epidermis was shown to resemble ashes and no cell wall of the epidermis was found. On the other hand, the epidermis of the receptacle was torn away with 1.0 or more kGy irradiation. The damaged spots of the receptacle epidermis also appeared after irradiation. Irradiation was not recommended for treating the fresh day-lily flowers as vegetables since the dosage (2.0 or more kGy) needed for inhibiting the flower blooming as shown in our previous works, caused injury on the epidermis of the flowers

Ultrastructural and ERG findings in progressive rod-cone dystrophy in a litter of Labrador retrievers.

Science.gov (United States)

Raitta, C; Kommonen, B; Ulshafer, R; Karhunen, U

1991-02-01

Early ultrastructural findings of a progressive photoreceptor dystrophy and corresponding ERG findings are reported in 3 Labrador Retrievers from a litter of 7 pups bred from 2 dogs clinically and electroretinographically affected with generalized progressive retinal dystrophy. The pups were euthanized at 5, 11 and 15 months post partum. The most prominent ultrastructural finding was photoreceptor dystrophy. At 5 months the outer nuclear layer (ONL) consisted of 8-10 layers and seemed reduced in thickness, pyknotic nuclei were seen in this layer. The receptor outer segments (OS) were short and swollen. Some disorientation of OS discs occurred. In the 11-months specimen 7-8 ONL layers were identified. Overall thinning of the neuro-retina had occurred and fewer receptors compared to the 5-months specimen were present. By 15 months the ONL was further reduced to about 4 layers. Enlarged internuclear spaces were present in the ONL as well as around inner segments (IS). Phagocytic cells were frequent among remains of OS. The pigment epithelium appeared normal. The dark adapted ERG b-wave amplitudes and photopic 30 Hz flicker responses were low in comparison to controls of the same breed, and decreased with age. The condition represents a progressive rod-cone dystrophy which shares similarities with primary receptor dystrophy in man such as retinitis pigmentosa.

Anatomical characterization of ultra-structures, biominerals and histolocalization of metabolites in leaves of Genipa americana

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Alex L. Vasconcelos

Full Text Available Abstract Inserted in one of the largest families among the Angiosperms, Genipa americana L., Rubiaceae, can be found in all Brazilian territory, presenting great medicinal importance, where several uses have been attributed. In view of this, this work has the purpose of analyzing the ultrastructural, biomineral, phytochemical and histochemical characteristics of the leaves of this native species from Brazil. For this, light microscopy, polarization and scanning electron microscopy techniques were used with X-ray scattering energy, associated to chromatographic and histochemical tests. The anatomical ultrastructural characteristics of the leaves detailed information about the type and arrangement of the cuticle, trichomes, surface and arrangement of the tissues that determine the botanical identity of this species. The phytochemical tests allowed determining their chromatographic pattern and histochemistry to determine the exact storage site of these substances in the leaf. It was observed that the characterization of the crystalline macro-pattern present in the analyzed species, as well as its exact elemental composition, can be considered an important differential diagnosis factor. The results characterize the leaves of this species in different aspects, being a native species and pharmacologically promising, with different popular uses and proven pharmacological activities, and more in depth studies is needed.

Ultrastructural aspects in perithecia hyphae septal pores of Glomerella cingulata F. SP. Phaseoli

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Roca M. María Gabriela

2000-01-01

Full Text Available Glomerella cingulata (Stonem. Spauld. & Schrenk f. sp. phaseoli, better known in its anamorphic state Colletotrichum lindemuthianum (Sacc. & Magn. Briosi & Cav., is a causal agent of anthracnose in beans (Phaseolus vulgaris L.. Ultrastructural aspects of the perithecial hyphae of this pathogen were studied. The perithecia hyphae septal pores were found either plugged by a vesicle or unplugged. Some perithecia hyphae septa presented no pore. The Woronin bodies, close to the septal pores, appeared as globose structures which were more electron dense than the occlusions plugging the septal pore.

[Structure and ultrastructure of the ovary of Cichlasoma urophthalmus (Osteichthyes: Cichlidae)].

Science.gov (United States)

Viedma, Rubí; Franco, Jonathan; Bedia, Carlos; Guedea Fernández, Guadalupe; Villa Zevallos, Héctor Barrera; Barrera Escorcia, Héctor

2011-06-01

The study of the normal development, differentiation, structure and function of various components of developing follicles in the ovaries of numerous fish species have been a consistent focus of comparative reproduction. The structural and ultrastructural features of gonads from Cichlasoma urophthalmus have received scarce attention. In this work, we realized a descriptive study of female gonads of Cichlasoma urophthalmus. A total of 40 samples were collected in the Veracruz Alvarado Lagoon, Mexico in 2007-2008 period including the windy, dry and rainy seasons. Female gonads were extracted and a portion was fixed in 4% formaldehyde for treatment for routine histology hematoxylin and eosin (HE) and another part was processed for transmission electron microscopy (TEM). The gonads were fixed in 3% glutaraldehyde and 2% osmium tetroxide, followed by dehydrated in ethanol 50%, 70%, 80%, 95% and 100% for inclusion in Epon, thin sections were then prepared and were contrasted with lead citrate and uranyl acetate. The process of oocyte development can be divided into five distinct stages (formation of oocytes from oogonia, primary growth, lipid stage, vitellogenesis and maturation). In this work, we found that the primary growth stage is characterized by intense RNA synthesis and the differentiation of the vitelline envelope. Secondary growth starts with the accumulation of lipid droplets in the oocyte cytoplasm (lipid stage), which is then followed by massive uptake and processing of proteins into yolk platelets (vitellogenic stage). During the maturation stage, the lipid inclusions coalesce into a single oil droplet, and hydrolysis of the yolk platelets leads to the formation of a homogeneous mass of fluid yolk in mature eggs. In conclusion, further studies should elucidate structure and ultrastructural changes in the ovarian follicular components, in C. urophthalmus during different stages of oocyte growth.

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

Science.gov (United States)

Kornakova, E E

2002-01-01

Ultrastructure of the epithelium of adult and juvenile Urastoma cyprinae has been studied. The epithelium of both adult and juvenile worms is cellular, ciliated and bears numerous microvilli. The cytoplasm is rich in large, numerous epitheliosomes of two types--electron-dense and with fibrillated content (fig. 1, a, [symbol: see text]; 2, a-[symbol: see text]). Besides large secrete granules small membrane-bounded vesicles were observed (fig. 2, a-[symbol: see text]). In juvenile worms the dense epitheliosomes are less abundant and the fibrillated content in the second type of granules has a different structure: the fibrils are very thin and more densely packed forming the structures of the less electron density (fig. 3, a, [symbol: see text], [symbol: see text] 1). The membrane-bounded vesicles in the epithelium of juvenile worms were not observed. All types of secrete are ejected by exocytosis (fig. 2, [symbol: see text]; 3, [symbol: see text], [symbol: see text]). The ultrastructure of the epithelium in juvenile U. cyprinae is strongly similar to that in parasitic turbellarian Kronborgia, especially to the epithelium in a male and a larva. The basal lamina consists of tree layers and forms numerous deep infoldings into the epithelium (fig. 1, a; 2, a; 3, a, [symbol: see text], [symbol: see text]). The basement membrane projects deep and numerous invaginations into the epithelium which may almost reach the apical membrane (fig. 1, a; 2, a, [symbol: see text], [symbol: see text]; 3, [symbol: see text]). Mitochondria are large and situated mainly near the projections of the basement membrane (fig. 2, [symbol: see text]-[symbol: see text]; 3, [symbol: see text]). Such ultrastructure implies an intensive process of the transmembrane transfer of the dissolved organic substances from the sea water. The same structures were found in the epithelium of Kronborgia. Uptake of organic compounds through the epithelium in the common ancestors of Urastoma and Kronborgia could

The ultrastructure of protein bodies isolated from Pisum sativum and Iris pseudoacorus L. seeds

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Barbara Gabara

2015-01-01

Full Text Available Protein bodies of Pisum sativum and Iris pseudoacorus seeds have been isolated in sucrose gradient with addition of 50mM citrate buffer, pH 5. Their ultrastructure due to isolation procedure has been described. Two types of protein bodies are present in pea and iris seeds: simple and compex ones - with many inclusions. The method of isolation, used in this paper extracts partly proteins - probably albumins, and also substances present in globoids i.e. phytin and acid phosphatase.

AFM of the ultrastructural and mechanical properties of lipid-raft-disrupted and/or cold-treated endothelial cells.

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Wu, Li; Huang, Jie; Yu, Xiaoxue; Zhou, Xiaoqing; Gan, Chaoye; Li, Ming; Chen, Yong

2014-02-01

The nonionic detergent extraction at 4 °C and the cholesterol-depletion-induced lipid raft disruption are the two widely used experimental strategies for lipid raft research. However, the effects of raft disruption and/or cold treatment on the ultrastructural and mechanical properties of cells are still unclear. Here, we evaluated the effects of raft disruption and/or cold (4 °C) treatment on these properties of living human umbilical vein endothelial cells (HUVECs). At first, the cholesterol-depletion-induced raft disruption was visualized by confocal microscopy and atomic force microscopy (AFM) in combination with fluorescent quantum dots. Next, the cold-induced cell contraction and the formation of end-branched filopodia were observed by confocal microscopy and AFM. Then, the cell-surface ultrastructures were imaged by AFM, and the data showed that raft disruption and cold treatment induced opposite effects on cell-surface roughness (a significant decrease and a significant increase, respectively). Moreover, the cell-surface mechanical properties (stiffness and adhesion force) of raft-disrupted- and/or cold-treated HUVECs were measured by the force measurement function of AFM. We found that raft disruption and cold treatment induced parallel effects on cell stiffness (increase) or adhesion force (decrease) and that the combination of the two treatments caused dramatically strengthened effects. Finally, raft disruption was found to significantly impair cell migration as previously reported, whereas temporary cold treatment only caused a slight but nonsignificant decrease in cell migration performed at physiological temperature. Although the mechanisms for causing these results might be complicated and more in-depth studies will be needed, our data may provide important information for better understanding the effects of raft disruption or cold treatment on cells and the two strategies for lipid raft research.

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

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Sameera Shamim Khan

2016-01-01

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

Ultrastructural apoptotic lesions induced in rat thymocytes after borax ingestion.

Science.gov (United States)

Sylvain, I C; Berry, J P; Galle, P

1998-01-01

Apoptosis has gained increasing attention in recent years. Several chemical compounds induce apoptotic lesions in the thymus. Male Wistar rats received 2000 ppm of borax (Na2B4O7.10H2O) in their food for 16 days. The rats were sacrificed 2, 5, 9, 12, 19, 21, 26 and 28 days after the beginning of treatment. Thymus samples of all rats were taken. A Philips EM 300 electron microscopy was used to study the ultrastructural morphology. Serious nuclear and cytoplasmic lesions were observed. Moreover, numerous macrophages containing apoptotic cells were present in the thymus. The alterations were observed from the 2nd to the 28th day. The extent of damage was much more important in the rats sacrificed 21, 26 and 28 days after borax ingestion.

Effect of Ultrastructure on Changes of Textural Characteristics between Crisp Grass Carp (Ctenopharyngodon Idellus C.Et V) and Grass Carp (Ctenopharyngodon Idellus) Inducing Heating Treatment.

Science.gov (United States)

Lin, Wan-Ling; Yang, Xian-Qing; Li, Lai-Hao; Hao, Shu-Xian; Wang, Jin-Xu; Huang, Hui; Wei, Ya; Wu, Yan-Yan

2016-02-01

The research studies the ultrastructure effect on texture of crisp grass carp (CGC) and grass carp (GC) fillets inducing heating for 15, 25, and 40 min with boiling water. After heating, the hardness, fracturability, springiness, chewiness, resilience, and cohesiveness of CGC were higher than that of raw CGC, whereas the all textural characteristics of heating GC were lower obviously than that of raw GC. The hardness, fracturability, springiness, chewiness, resilience, and cohesiveness of CGC for heating 15 min were higher by 6.3%, 9.0%, 27.0%, 71.8%, 9.4%, and 23.9%, respectively, than that of raw CGC (RCGC). The hardness increasing of CGC flesh with the extension of heating time related closely to more coagulating connective tissue in interstitial spaces, especially relating to smaller muscle fiber diameter and denser muscle fiber density. The more and larger spaces between fiber and fiber with the extension of heating time results in the decrease of cohesiveness and resilience of CGC flesh. For chewiness, the stronger chewiness of cooked CGC associated with more detachment of myofiber-myocommata and fiber-fiber. Overall, the results show that the changes of texture characteristics of CGC fillet with extension of heating time correlates positively with the ultrastructure. © 2016 Institute of Food Technologists®

The ultrastructure of tumor cells in patients with rectal cancer after pre-operative irradiation and intra-operative cryotherapy

International Nuclear Information System (INIS)

Vyinnik, Yu.O.; Kotenko, O.Je.; Nevzorov, V.P.; Chyibyisov, L.P.

2000-01-01

Electronic microscopy of the tumor cells was performed to confirm the efficacy of combined pre-operative gamma-therapy and intraoperative cryotherapy (CT). Pre-operative irradiation at the dose of 20 Gy accompanied by intra-operative cryotherapy caused the changes in the ultrastructure, the depth and degree of which allow to consider them destructive and irreversible

Changes in lignocellulosic supramolecular and ultrastructure during dilute acid pretreatment of Populus and switchgrass

International Nuclear Information System (INIS)

Foston, Marcus; Ragauskas, Art J.

2010-01-01

Dilute acid pretreatment (DAP) is commonly employed prior to enzymatic deconstruction of cellulose to increase overall sugar and subsequent ethanol yields from downstream bioconversion processes. Typically optimization of pretreatment is evaluated by determining hemicellulose removal, subsequent reactivity towards enzymatic deconstruction, and recoverable polysaccharide yields. In this study, the affect of DAP on the supramolecular and ultrastructure of lignocellulosic biomass was evaluated. A series of dilute acidic pretreatments, employing ∼0.10-0.20 mol/m 3 H 2 SO 4 at ∼160-180 o C, for varying residence times were conducted on both Populus and switchgrass samples. The untreated and pretreated biomass samples were characterized by carbohydrate and lignin analysis, gel permeation chromatography (GPC) and 13 C cross polarization magic angle spinning (CPMAS) NMR spectroscopy. GPC analysis shows a reduction in the molecular weight of cellulose and change in its polydispersity index (PDI) with increasing residence time, indicating that pretreatment is actually degrading the cellulose chains. 13 C CPMAS and non-linear line-fitting of the C 4 region in the carbon spectrum of the isolated cellulose not only showed that the crystallinity index increases with residence time, but that the lateral fibril dimension (LFD) and lateral fibril aggregate dimension (LFAD) increase as well.

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

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Arias Covadonga R

2012-11-01

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

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

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

2014-12-24

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

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

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Havva Dashtdar

2016-03-01

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

EFFECT OF CYCLOSPORINE A ON THE KIDNEY OF RABBIT: A LIGHT AND ULTRASTRUCTURAL STUDY

OpenAIRE

Fathy Ahmed Fetouh; Abdelmonem Awad Hegazy

2014-01-01

Background: Nephrotoxicity is a relatively common problem in patients immunosuppressed with cyclosporine A (CsA) with an incidence reaching up to thirty percent. The present work aimed to study the histological and ultrastructural effects of CsA on the kidney of rabbit. Materials and Methods: Two groups of Egyptian adult rabbits were used for this study (5 rabbits for each). One group was used as a control and the other group (experimental) was treated with CsA in a dose of 15 mg/kg of bod...

Distribution and ultrastructure of pigment cells in the skins of normal and albino adult turbot, Scophthalmus Maximus

Institute of Scientific and Technical Information of China (English)

GUO Huarong; HUANG Bing; QI Fei; ZHANG Shicui

2007-01-01

The distribution and ultrastructure of pigment cells in skins of normal and albino adult turbots were examined with transmission electron microscopy (TEM). Three types of pigment cells of melanophore, iridophore and xanthophore have been recognized in adult turbot skins. The skin color depends mainly on the amount and distribution of melanophore and iridophore, as xanthophore is quite rare. No pigment cells can be found in the epidermis of the skins. In the pigmented ocular skin of the turbot, melanophore and iridophore are usually co-localized in the dermis. This is quite different from the distribution in larvae skin. In albino and white blind skins of adult turbots, however, only iridophore monolayer still exists, while the melanophore monolayer disappears. This cytological evidence explains why the albino adult turbot, unlike its larvae, could never resume its body color no matter what environmental and nutritional conditions were provided. Endocytosis is quite active in the cellular membrane of the iridophore. This might be related to the formation of reflective platelet and stability of the iridophore.

Ultrastructural localization of lead in Stigeoclonium tenue (chlorophyceae, ulotrichales) as demonstrated by cytochemical and x-ray microanalysis

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Silverberg, B A

1975-12-01

Results of ultrastructural studies and TEM-X-ray microanalysis of the ulotrichalean alga Stigeoclonium tenue experimentally exposed to increasing concentrations of lead nitrate are presented. A fine-structural examination of the cells revealed that detectable amounts of lead (Pb) had entered the cytoplasm and could be recognized most easily as electron-dense precipitates localized on the cell wall and within the two large peripheral vacuoles. Dense deposits were never observed in mitochondria, plastids or nuclei. Pinocytotic vacuoles containing lead spheroids are removed endocytotically to the cytoplasmic vacuoles, rendering the Pb innocuous. The evidence suggests that the cell wall and vacuoles are important structures in maintaining a relatively low cytoplasmic concentration of lead, thereby reducing the toxic effects of lead ions on sensitive cellular functions. At high concentrations, ranging from 0.15 to 0.5 mg Pb/l, noticeable alterations in the fine structure of the chloroplast are evident. A method is described for the visualization of Pb deposits in fresh, chemically fixed and plastic-embedded material using a saturated solution of sodium rhodizonate.

Morphological and ultrastructural characteristics of extracellular matrix changes in oral squamous cell carcinoma

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Usha Agrawal

2011-01-01

Full Text Available Background: The biology of oral squamous cell carcinoma (OSCC, including its progression from dysplasia to carcinoma, "field effects", genetic changes in tumor associated mucosa (TAM and effect of matrix metalloproteinases in breaking down of matrix proteins to facilitate invasion, has been well documented. However, what remains to be done is to extrapolate this knowledge to improve patient care. Aim: The aim of this study was to observe the extracellular matrix (ECM changes with the routine histochemical stains available to most histopathologists. Materials and Methods: The study includes 72 cases of OSCC in which the tumor and adjacent normal appearing areas were sampled to study the ECM changes with hematoxylin and eosin (H and E and Verhoeff′s-Van Gieson elastic stain (VVG. Results: Basophilic fragmentation of collagen (H and E and clumped short elastic fibers (VVG were seen in 12 (16.7% cases. Of the remaining cases, 18 (25% had a dense lymphocytic infiltrate and had no demonstrable elastic fibers. Those cases with H and E changes were further studied and compared with normal mucosa for ultrastructural changes. The ultrastructural study demonstrated an increase in oxytalan, elaunin and elastic fibers and decrease in collagen fibers with some transformation changes associated with OSCCs and lymph node metastasis. Conclusion: Changes in transformation of collagen to elastic fibers and also the loss of both the fibers in areas of lymphocytic infiltration possibly indicate degradation of ECM fibers by factors released from the lymphocytes or tumor cells and the limiting effect on the tumor by ECM remodeling.

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

Energy Technology Data Exchange (ETDEWEB)

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

1982-01-01

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

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

International Nuclear Information System (INIS)

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

1982-01-01

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

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

Science.gov (United States)

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

2015-09-01

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

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

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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.

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

Science.gov (United States)

Assugeni, Camila de O; Magalhães, Tatiana; Bolaños, Juan A; Tudge, Christopher C; Mantelatto, Fernando L; Zara, Fernando J

2017-12-01

Recent studies based on morphological and molecular data provide a new perspective concerning taxonomic aspects of the brachyuran family Mithracidae. These studies proposed a series of nominal changes and indicated that the family is actually represented by a different number and representatives of genera than previously thought. Here, we provide a comparative description of the ultrastructure of spermatozoa and spermatophores of some species of Mithracidae in a phylogenetic context. The ultrastructure of the spermatozoa and spermatophore was observed by scanning and transmission electron microscopy. The most informative morphological characters analysed were thickness of the operculum, shape of the perforatorial chamber and shape and thickness of the inner acrosomal zone. As a framework, we used a topology based on a phylogenetic analysis using mitochondrial data obtained here and from previous studies. Our results indicate that closely related species share a series of morphological characteristics of the spermatozoa. A thick operculum, for example, is a feature observed in species of the genera Amphithrax, Teleophrys, and Omalacantha in contrast to the slender operculum observed in Mithraculus and Mithrax. Amphithrax and Teleophrys have a rhomboid perforatorial chamber, while Mithraculus, Mithrax, and Omalacantha show a wider, deltoid morphology. Furthermore, our results are in agreement with recently proposed taxonomic changes including the separation of the genera Mithrax (previously Damithrax), Amphithrax (previously Mithrax) and Mithraculus, and the synonymy of Mithrax caribbaeus with Mithrax hispidus. Overall, the spermiotaxonomy of these species of Mithracidae represent a novel set of data that corroborates the most recent taxonomic revision of the family and can be used in future taxonomic and phylogenetic studies within this family. © 2017 Wiley Periodicals, Inc.

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

Science.gov (United States)

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

2017-05-24

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

Photosynthetic Characteristics and Chloroplast Ultrastructure of Summer Maize Response to Different Nitrogen Supplies.

Science.gov (United States)

Liu, Zheng; Gao, Jia; Gao, Fei; Liu, Peng; Zhao, Bin; Zhang, Jiwang

2018-01-01

Maize ( Zea mays L.) is the important crop over the world. Nitrogen (N) as necessary element affects photosynthetic characteristics and grain yield of summer maize. In this study, N0 (0 kg N ha -1 ), N1 (129 kg N ha -1 ), N2 (185 kg N ha -1 ), and N3 (300 kg N ha -1 ) was conducted using hybrid 'ZhengDan958' at Dawenkou research field (36°11'N, 117°06'E, 178 m altitude) in the North China Plain to explore the effects of N rate on photosynthetic characteristics and chloroplast ultrastructure. Gas exchange parameters, chlorophyll fluorescence parameters, leaf area index (LAI), chlorophyll SPAD value, chloroplast ultrastructure, dry matter weight and grain yield were measured. At physiological maturity stage, dry matter weight and grain yield of N2 increased by 33-52% ( P ≤ 0.05) and 6-32% ( P ≤ 0.05), respectively, compared with other treatments. During the growing from silking (R1) to milk (R3) stage, LAI of N0 and N1 were 35-38% ( P ≤ 0.05) and 9-23% ( P ≤ 0.05) less than that of N2, respectively. Chlorophyll SPAD value of N0 and N1 were 13-22% ( P ≤ 0.05) and 5-11% ( P ≤ 0.05) lower than that of N2. There was no significant difference in LAI and chlorophyll SPAD value between N2 and N3 during the period from R1 to R3 ( P > 0.05). The net photosynthetic rate ( P n ), maximal quantum efficiency of PSII ( F v / F m ) and quantum efficiency of PSII (Φ PSII ) were higher with the increase of N rate up to N2 ( P ≤ 0.05), and those of N3 were significantly less than N2 ( P ≤ 0.05). In compared with N2, the chloroplast configuration of N0 and N1 became elliptical, almost circular or irregular. The membrane of chloroplast and thylakoid resolved with growing stage, and the number of chloroplast per cell and lamellae per grana decreased under N0 and N1 treatment ( P ≤ 0.05). Under N0 and N1 treatments, summer maize had more negative photosynthetic characteristics. The more number of osmium granule and vesicle and the larger gap between lamellae were

Photosynthetic Characteristics and Chloroplast Ultrastructure of Summer Maize Response to Different Nitrogen Supplies

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Zheng Liu

2018-05-01

Full Text Available Maize (Zea mays L. is the important crop over the world. Nitrogen (N as necessary element affects photosynthetic characteristics and grain yield of summer maize. In this study, N0 (0 kg N ha-1, N1 (129 kg N ha-1, N2 (185 kg N ha-1, and N3 (300 kg N ha-1 was conducted using hybrid ‘ZhengDan958’ at Dawenkou research field (36°11′N, 117°06′E, 178 m altitude in the North China Plain to explore the effects of N rate on photosynthetic characteristics and chloroplast ultrastructure. Gas exchange parameters, chlorophyll fluorescence parameters, leaf area index (LAI, chlorophyll SPAD value, chloroplast ultrastructure, dry matter weight and grain yield were measured. At physiological maturity stage, dry matter weight and grain yield of N2 increased by 33–52% (P ≤ 0.05 and 6–32% (P ≤ 0.05, respectively, compared with other treatments. During the growing from silking (R1 to milk (R3 stage, LAI of N0 and N1 were 35–38% (P ≤ 0.05 and 9–23% (P ≤ 0.05 less than that of N2, respectively. Chlorophyll SPAD value of N0 and N1 were 13–22% (P ≤ 0.05 and 5–11% (P ≤ 0.05 lower than that of N2. There was no significant difference in LAI and chlorophyll SPAD value between N2 and N3 during the period from R1 to R3 (P > 0.05. The net photosynthetic rate (Pn, maximal quantum efficiency of PSII (Fv/Fm and quantum efficiency of PSII (ΦPSII were higher with the increase of N rate up to N2 (P ≤ 0.05, and those of N3 were significantly less than N2 (P ≤ 0.05. In compared with N2, the chloroplast configuration of N0 and N1 became elliptical, almost circular or irregular. The membrane of chloroplast and thylakoid resolved with growing stage, and the number of chloroplast per cell and lamellae per grana decreased under N0 and N1 treatment (P ≤ 0.05. Under N0 and N1 treatments, summer maize had more negative photosynthetic characteristics. The more number of osmium granule and vesicle and the larger gap between lamellae were shown in N3

Ultrastructural aspects of experimental cryptosporidiosis in pigs Aspectos ultraestruturais da criptosporidiose experimental em suínos

Directory of Open Access Journals (Sweden)

A.P.F.R.L. Bracarense

1999-10-01

Full Text Available The aim of this work was to determine ultrastructural changes on the intestinal mucosa and associated lymphoid tissues after an experimental infection with Cryptosporidium sp. Twelve piglets dosed orally with 1×10(6 oocysts were slaughtered on days 3, 6, 9 and 12 after inoculation. The ultrastructural lesions in the intestinal cells were irregular with thickened microvilli, cytoplasmic protrusions and vacuolation, swollen mitochondria, hypertrophic organelles and nuclei. The lymphocytes of the Peyer’s patches occasionally were mitotic with a larger number of lymphoblasts in the inoculated animals.O presente estudo teve por objetivo investigar as alterações ultraestruturais da mucosa intestinal e do tecido linfóide associado na inoculação experimental de Cryptosporidium sp. Doze leitões foram inoculados experimentalmente por via oral com 1×10(6 oocistos e sacrificados 3, 6, 9 e 12 dias depois. Ao exame ultraestrutural de células intestinais observou-se espessamento e irregularidade de microvilosidades, citoplasma vacuolizado e com protrusões, edema mitocondrial, hipertrofia de organelas citoplasmáticas e do núcleo. Nas placas de Peyer observou-se ocasionalmente mitose de células linfóides, verificando-se maior número de células blásticas.

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

International Nuclear Information System (INIS)

Zhuang, Zhi; Yoshimura, Hideyuki; Aizawa, Mamoru

2013-01-01

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

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

Science.gov (United States)

Uranova, N A; Kolomeets, N S; Vikhreva, O V; Zimina, I S; Rakhmanova, V I; Orlovskaya, D D

Previously the authors have reported the ultrastructural pathology of myelinated fibers (MF) in the brain in schizophrenia. The aim of the present study was to compare the effect of disease course on ultrastructural changes of MF. Postmortem electron microscopic morphometric study of MF was performed in the prefrontal cortex, caudate nucleus and hippocampus in 19 cases of paranoid schizophrenia. Fourteen cases of continuous schizophrenia, 5 cases of attack-like schizophrenia and 25 normal matched control cases were studied. The proportion (percentage) of pathological MF was estimated in the prefrontal cortex, layer 5, CA3 area of hippocampus, pyramidal layer, and in the head of the caudate nucleus. The percentage of MF having axonal atrophy and swelling of periaxonal oligodendrocyte process was significantly higher in both continuous and attack-like schizophrenia in all brain structures studied as compared to the control group. In the hippocampus and caudate nucleus, this parameter was increased significantly in attack-like schizophrenia as compared to continuous schizophrenia. In the prefrontal cortex. The percentage of the pathological MF having signs of deformation and destruction of myelin sheaths increased significantly only in continuous schizophrenia as compared to the control group. MF pathology is similar in attack-like and continuous paranoid schizophrenia but differ by the degree of severity of pathological MF. Abnormalities in MF contribute to the disconnectivity between the prefrontal cortex, caudate nucleus and hippocampus.

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

Energy Technology Data Exchange (ETDEWEB)

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

2013-07-01

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

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

Directory of Open Access Journals (Sweden)

CHEHTER Ethel Zimberg

2001-01-01

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

III. Cellular ultrastructures in situ as key to understanding tumor energy metabolism: biological significance of the Warburg effect.

Science.gov (United States)

Witkiewicz, Halina; Oh, Phil; Schnitzer, Jan E

2013-01-01

Despite the universality of metabolic pathways, malignant cells were found to have their metabolism reprogrammed to generate energy by glycolysis even under normal oxygen concentrations (the Warburg effect). Therefore, the pathway energetically 18 times less efficient than oxidative phosphorylation was implicated to match increased energy requirements of growing tumors. The paradox was explained by an abnormally high rate of glucose uptake, assuming unlimited availability of substrates for tumor growth in vivo. However, ultrastructural analysis of tumor vasculature morphogenesis showed that the growing tissue regions did not have continuous blood supply and intermittently depended on autophagy for survival. Erythrogenic autophagy, and resulting ATP generation by glycolysis, appeared critical to initiating vasculature formation where it was missing. This study focused on ultrastructural features that reflected metabolic switch from aerobic to anaerobic. Morphological differences between and within different types of cells were evident in tissue sections. In cells undergoing nucleo-cytoplasmic conversion into erythrosomes (erythrogenesis), gradual changes led to replacing mitochondria with peroxisomes, through an intermediate form connected to endoplasmic reticulum. Those findings related to the issue of peroxisome biogenesis and to the phenomenon of hemogenic endothelium. Mitochondria were compacted also during mitosis. In vivo, cells that lost and others that retained capability to use oxygen coexisted side-by-side; both types were important for vasculature morphogenesis and tissue growth. Once passable, the new vasculature segment could deliver external oxygen and nutrients. Nutritional and redox status of microenvironment had similar effect on metabolism of malignant and non-malignant cells demonstrating the necessity to maintain structure-energy equivalence in all living cells. The role of glycolysis in initiating vasculature formation, and in progression of

Gamma radiation effect on the mitochondria ultrastructure in different radiosensitive types of cotton plants

Energy Technology Data Exchange (ETDEWEB)

Arslanov, S V

1973-01-01

When germinated seeds are irradiated with a dose of 10 krad, the mitochondrial ultrastructure is disrupted in the early-ripening 1306-DV and the late-ripening S-1622 varieties of the cotton-plant. The mitochondria exhibited swelling, breakdown of internal structure and vacuolation. In the S-1622 variety the mitochondria shrink owing to their small number and larger size and to the smaller number of cristae. Changes in the ultrafine organization of mitochondria lead to inhibition of carbohydrate oxidation through the Krebs cycle and intensification of oxidation through the pentosophosphate cycle.

Ozone effects on radish (Raphanus sativus L. cv. Cherry Belle): gradient of ultrastructural changes

Energy Technology Data Exchange (ETDEWEB)

Athanassious, R.

1980-01-01

Ultrastructural changes produced by low ( less than or equal to 0.5 ppm) levels of ozone may be attributed to water deficit resulting from injury to the sensitive paravenial cells. The drastic alterations, resulting from high ( greater than or equal to 0.5 ppm) ozone concentrations, were apparently due to more direct effects. Although differential fixation images of membranes in control and ozone treated leaves were not obtained the significance of ozone attacking the olefinic groups of fatty acids in the membrane bilayer should not be completely ignored. 19 references, 12 figures.

Ultrastructure of the spermatozoon of Dipylidium caninum (Cestoda, Cyclophyllidea, Dilepididae), an intestinal parasite of Canis familiaris.

Science.gov (United States)

Miquel, J; Marchand, B

1997-01-01

We report for the first time the ultrastructure of the spermatozoon of a Dilepididae cestode. The mature spermatozoa of Dipylidium caninum is filiform and tapered at both ends and lacks mitochondria. The anterior extremity exhibits an apical cone of electron-dense material measuring about 600 nm in length and a single helicoidal crested-like body that is 150 nm thick. This single crested-like body is spiralized at an angle of about 40 degrees to the spermatozoon axis. The axoneme, showing the 9 + "l" pattern of the Platyhelminthes, lacks a periaxonemal sheath. The cortical microtubules constitute a continuous, submembranous, electron-dense material, and they are also twisted at an angle of about 40 degrees to the spermatozoon axis. Moreover, the nucleus is coiled in a helix around the axoneme, which is centrally located throughout its length. We demonstrate for the first time the presence of peripheral microtubules twisted to the spermatozoon axis up to the posterior extremity of the gamete.

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

Science.gov (United States)

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

2015-10-01

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

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

Science.gov (United States)

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

2000-05-01

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

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

Directory of Open Access Journals (Sweden)

Pinelli Leonardo

2001-06-01

Full Text Available Abstract 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.

Low tendon stiffness and abnormal ultrastructure distinguish classic Ehlers-Danlos syndrome from benign joint hypermobility syndrome in patients

DEFF Research Database (Denmark)

Nielsen, Rie Harboe; Couppé, Christian; Jensen, Jacob Kildevang

2014-01-01

There is a clinical overlap between classic Ehlers-Danlos syndrome (cEDS) and benign joint hypermobility syndrome (BJHS), with hypermobility as the main symptom. The purpose of this study was to investigate the role of type V collagen mutations and tendon pathology in these 2 syndromes. In patients...... and abnormal ultrastructure distinguish classic Ehlers-Danlos syndrome from benign joint hypermobility syndrome in patients....

Ultrastructural Investigation of Pelvic Peritoneum in Patients With Chronic Pelvic Pain and Subtle Endometriosis in Association With Chromoendoscopy.

Science.gov (United States)

Mehdizadehkashi, Abolfazl; Tahermanesh, Kobra; Fazel Anvari-Yazdi, Abbas; Chaichian, Shahla; Azarpira, Negar; Nobakht, Maliheh; Abed, Seyedeh Mehr; Hashemi, Neda

2017-01-01

To evaluate the pelvic peritoneum under chromoendoscopy by scanning electron microscopy (SEM) as well as light microscopy with hematoxylin and eosin staining and immunohistochemistry (IHC) assays in patients with chronic pelvic pain (CPP) associated with subtle endometriosis. Case series study (Canadian Task Force classification II). A referral academic community tertiary medical center. Three women aged 29 to 37 years were referred to the obstetrics and gynecology clinic of the tertiary university hospital with CPP. They were suspicious for endometriosis, were not responding to medical treatments, and had undergone previous pelvic laparoscopy to determine the stage of endometriosis and preparation of peritoneal samples under the guidance of staining with methylene blue in 0.25% dilution. Comparison of stained and unstained pelvic peritoneal samples after the instillation of 0.25% methylene blue into the pelvic cavity. In 3 patients, laparoscopic examination showed minimal endometriosis. A total of 18 samples (9 stained and 9 unstained) from the 3 patients were prepared for SEM. Ten of the samples (55.6%) showed microstructural peritoneal destruction (7 of 9 stained [77.7%] and 3 of 9 [33.4%] unstained). Eighteen samples (9 stained and 9 unstained) from the 3 patients were also prepared for IHC. Six of these samples (33.3%) were S-100-positive, including 4 of 9 (44.4%) stained samples and 2 of 9 (22.2%) unstained samples. In general, in the context of CPP and endometriosis, there is no established relationship between the severity of pain and stage of endometriosis. In the pathophysiology of CPP associated with endometriosis, ultrastructural changes can play a significant role. Under methylene blue staining, some destroyed areas were detected, but the stained areas do not necessarily correlate with increased microstructural peritoneal destruction. Copyright © 2016 AAGL. Published by Elsevier Inc. All rights reserved.