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Sample records for cellular proliferation ultrastructure

  1. HIV aspartyl peptidase inhibitors interfere with cellular proliferation, ultrastructure and macrophage infection of Leishmania amazonensis.

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    Lívia O Santos

    Full Text Available BACKGROUND: Leishmania is the etiologic agent of leishmanisais, a protozoan disease whose pathogenic events are not well understood. Current therapy is suboptimal due to toxicity of the available therapeutic agents and the emergence of drug resistance. Compounding these problems is the increase in the number of cases of Leishmania-HIV coinfection, due to the overlap between the AIDS epidemic and leishmaniasis. METHODOLOGY/PRINCIPAL FINDINGS: In the present report, we have investigated the effect of HIV aspartyl peptidase inhibitors (PIs on the Leishmania amazonensis proliferation, ultrastructure, interaction with macrophage cells and expression of classical peptidases which are directly involved in the Leishmania pathogenesis. All the HIV PIs impaired parasite growth in a dose-dependent fashion, especially nelfinavir and lopinavir. HIV PIs treatment caused profound changes in the leishmania ultrastructure as shown by transmission electron microscopy, including cytoplasm shrinking, increase in the number of lipid inclusions and some cells presenting the nucleus closely wrapped by endoplasmic reticulum resembling an autophagic process, as well as chromatin condensation which is suggestive of apoptotic death. The hydrolysis of HIV peptidase substrate by L. amazonensis extract was inhibited by pepstatin and HIV PIs, suggesting that an aspartyl peptidase may be the intracellular target of the inhibitors. The treatment with HIV PIs of either the promastigote forms preceding the interaction with macrophage cells or the amastigote forms inside macrophages drastically reduced the association indexes. Despite all these beneficial effects, the HIV PIs induced an increase in the expression of cysteine peptidase b (cpb and the metallopeptidase gp63, two well-known virulence factors expressed by Leishmania spp. CONCLUSIONS/SIGNIFICANCE: In the face of leishmaniasis/HIV overlap, it is critical to further comprehend the sophisticated interplays among Leishmania

  2. Cellular and ultrastructural characterization of the grey-morph phenotype in southern right whales (Eubalaena australis.

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    Guy D Eroh

    Full Text Available Southern right whales (SRWs, Eubalena australis are polymorphic for an X-linked pigmentation pattern known as grey morphism. Most SRWs have completely black skin with white patches on their bellies and occasionally on their backs; these patches remain white as the whale ages. Grey morphs (previously referred to as partial albinos appear mostly white at birth, with a splattering of rounded black marks; but as the whales age, the white skin gradually changes to a brownish grey color. The cellular and developmental bases of grey morphism are not understood. Here we describe cellular and ultrastructural features of grey-morph skin in relation to that of normal, wild-type skin. Melanocytes were identified histologically and counted, and melanosomes were measured using transmission electron microscopy. Grey-morph skin had fewer melanocytes when compared to wild-type skin, suggesting reduced melanocyte survival, migration, or proliferation in these whales. Grey-morph melanocytes had smaller melanosomes relative to wild-type skin, normal transport of melanosomes to surrounding keratinocytes, and normal localization of melanin granules above the keratinocyte nuclei. These findings indicate that SRW grey-morph pigmentation patterns are caused by reduced numbers of melanocytes in the skin, as well as by reduced amounts of melanin production and/or reduced sizes of mature melanosomes. Grey morphism is distinct from piebaldism and albinism found in other species, which are genetic pigmentation conditions resulting from the local absence of melanocytes, or the inability to synthesize melanin, respectively.

  3. Study of cellular proliferation kinetics in human breast cancer

    International Nuclear Information System (INIS)

    Angeles Rios, M.; Isabel Torres, D.; Tkachenko, G.; Perez, C.; Diaz, J.W.; Moreno, J.

    1981-01-01

    We present the preliminary results of cellular proliferation studies conducted in 35 patients with positive diagnosis of breast cancer treated at IOR mastology service. In measuring cellular proliferation from cancer samples, we evaluated thymidine labelling rates (TLR) though the use of an autoradiographic technique having cancer cells undergo a labelling pulse with triatiated thymidine. The results show a correlation between proliferation parameters and mitosis in the histological study, age of patients and presence of estrogenic receptors in cancer tissue. No correlation with the presence of metastatic nodes was found. (author)

  4. Advances in light-based imaging of three-dimensional cellular ultrastructure.

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    Kanchanawong, Pakorn; Waterman, Clare M

    2012-02-01

    Visualization methods are key to gaining insights into cellular structure and function. Since diffraction has long confined optical microscopes to a resolution no better than hundreds of nanometers, the observation of ultrastructural features has traditionally been the domain of electron microscopes (EM). In the past decade, however, advances in super-resolution fluorescence microscopy have considerably expanded the capability of light-based imaging techniques. Advantages of fluorescent labeling such as high sensitivity, specificity, and multichannel capability, can now be exploited to dissect ultrastructural features of cells. With recent methods capable of imaging specific proteins with a resolution on the order of a few tens of nanometers in 3-dimensions, this has made it possible to elucidate the molecular organization of many complex cellular structures. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Ultrastructural changes associated with cryopreservation of banana ( Musa spp.) highly proliferating meristems.

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    Helliot, B; Swennen, R; Poumay, Y; Frison, E; Lepoivre, P; Panis, B

    2003-03-01

    Cryopreservation has been shown to improve the frequency of virus elimination - specifically cucumber mosaic virus and banana streak virus - from banana ( Musa spp.) plants. To understand the mode of action of cryopreservation for the eradication of viral particles, we examined the ultrastructure of meristem tips at each step of the cryopreservation process. Excised meristematic clumps produced from infected banana plants belonging to cv. Williams (AAA, Cavendish subgroup) were cryopreserved through vitrification using the PVS-2 solution. We demonstrated that the cryopreservation method used only allowed survival of small areas of cells in the meristematic dome and at the base of the primordia. Cellular and subcellular changes occurring during the cryopreservation process are discussed.

  6. The kinetics of cellular proliferation in regenerating liver.

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    Fabrikant, J I

    1968-03-01

    The study concerns the kinetics of cellular proliferation in the different cell populations of the normal and regenerating rat liver. A detailed analysis is presented, which includes techniques of in vivo labeling of DNA with tritiated thymidine and high-resolution radioautography, of the temporal and spatial patterns of DNA synthesis and cell division in the parenchymal cells, littoral cells, bile duct epithelium, and other cellular components in the liver during the first 64 hr of regeneration after partial hepatectomy. The analysis of cell population kinetics indicates that (a) the rate of entry of parenchymal cells into synthesis, after an initial burst of proliferative activity, was an orderly progression at 3-4%/hr; (b) most cells divided once and a few twice, a large proportion of the cell deficit being replaced by 72 hr after the onset of proliferation; (c) T(s) was approximately 8.0 hr; T(gg2+m/2), 3.0 hr; and M, approximately 1.0 hr. Littoral cell proliferation began about 24 hr after the onset of parenchymal cell proliferation; the rate of entry of littoral cells into synthesis was greater than 4%/hr. Interlobular bile duct cell proliferation lagged well behind the parenchymal and littoral cell populations both in time and extent of proliferation.

  7. [Bone and Stem Cells. Cellular network in bone micro-environment - histological and ultrastructural aspects -].

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    Amizuka, Norio; Yamamoto, Tomomaya; Hasegawa, Tomoka

    2014-04-01

    Bone micro-environment appears to reflect bone turnover, i.e., frequency of bone remodeling. There are many bone-synthesizing mature osteoblasts, bone-resorbing osteoclasts, and a thick cell layer of preosteoblasts overlying mature osteoblasts in the region which shows active bone remodeling. Bone lining cells, - flattened, resting form of osteoblasts cover the quiescent bone surface, in which, however, osteocyte-lacunar canalicular system tend to be geometrically well-arranged. Thus, bone micro-environment seems to be regulated by preosteoblasts, bone marrow stromal cells and vascular endothelial cells, as well as osteoblasts and osteoclasts. But, precious biological function of preosteoblasts and bone marrow stromal cells are still under the investigation, e.g., due to many phenotypes of preosteoblasts. In this review, we will introduce histological and ultrastructural aspects on cellular involvement in bone micro-environment.

  8. Stimulation of Cellular Proliferation by Hepatitis B Virus X Protein

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    Charles R. Madden

    2001-01-01

    Full Text Available Chronic infection with the hepatitis B virus (HBV is a known risk factor in the development of human hepatocellular carcinoma (HCC. The HBV-encoded X protein, HBx, has been investigated for properties that may explain its cancer cofactor role in transgenic mouse lines. We discuss here recent data showing that HBx is able to induce hepatocellular proliferation in vitro and in vivo. This property of HBx is predicted to sensitize hepatocytes to other HCC cofactors, including exposure to carcinogens and to other hepatitis viruses. Cellular proliferation is intimately linked to the mechanism(s by which most tumor-associated viruses transform virus-infected cells. The HBx alteration of the cell cycle provides an additional mechanism by which chronic HBV infection may contribute to HCC.

  9. Glucocorticoid inhibition of cellular proliferation in rat hepatoma cell lines

    International Nuclear Information System (INIS)

    Cook, P.W.

    1987-01-01

    Glucocorticoids were shown to inhibit the growth rate of Fu5 rat hepatoma cells cultured in the presence or absence of serum and thus, induced a more stringent dependence on serum for growth in this cell line. Fu5 cells, made quiescent at low cell density by continuous exposure to glucocorticoid in the absence of serum, were induced with serum and insulin, which subsequently caused a rapid reinitiation of cellular proliferation. Analysis of total RNA isolated from hormone treated Fu5 cells undergoing serum/insulin induction of DNA synthesis revealed a sequential expression of cellular proto-oncogene products in the absence of any immediate changes in intracellular Ca ++ levels. Introduction of functional glucocorticoid receptor genes into both classes of dexamethasone resistant variants restored glucocorticoid responsiveness and suppression of cell growth. The BDS1 rat hepatoma cell line, an Fu5 derived subclone hypersensitive to the antiprofliferation effects of glucocorticoid, was observed to externalize a glucocorticoid suppressible mitogen (GSM) activity capable of mimicking EGF and insulin induced stimulation of [ 3 H]thymidine incorporation into serum starved, competant Balb/c 3T3 cells

  10. Cellular proliferation and regeneration following tissue damage. Progress report

    International Nuclear Information System (INIS)

    Harding, C.V.

    1977-01-01

    Studies were conducted on the following research projects: effects of x radiation on rabbit lenses; DNA synthesis and mitosis in cultured lenses; serum dependency and actinomycin D sensitivity; changes in ultrastructure; injury-induced growth of vascular endothelium; corneal neovascularization following injury; and human cataractous lenses

  11. Lipids, lipid droplets and lipoproteins in their cellular context; an ultrastructural approach

    NARCIS (Netherlands)

    Mesman, R.J.

    2013-01-01

    Lipids are essential for cellular life, functioning either organized as bilayer membranes to compartmentalize cellular processes, as signaling molecules or as metabolic energy storage. Our current knowledge on lipid organization and cellular lipid homeostasis is mainly based on biochemical data.

  12. Ultrastructural characterization of the pulmonary cellular defences in the lung of a bird, the rock dove, Columba livia

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    Maina, J. N.; Cowley, H. M.

    1998-01-01

    Free (surface) avian respiratory macrophages (FARMs) were harvested by lavage of the lung/air-sac system of the rock dove, Columba livia. The presence of FARMs in the atria and infundibula was confirmed by scanning electron microscopy. The respiratory system has developed several cellular defence lines that include surface macrophages, epithelial, subepithelial and interstitial phagocytes, and pulmonary intravascular macrophages (PIMs). Hence, C. livia appears to have a multiple pulmonary cellular protective armoury. Ultrastructurally, the FARMs and the PIMs were similar to the corresponding cells of mammals. The purported high susceptibility of birds to respiratory diseases, a state that has largely been deduced from morbidities and mortalities of commercial birds, and which has chiefly been attributed to paucity of the FARMs, is not supported by the present observations.

  13. Cellular Morphology-Mediated Proliferation and Drug Sensitivity of Breast Cancer Cells

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    Ryota Domura

    2017-06-01

    Full Text Available The interpretation of the local microenvironment of the extracellular matrix for malignant tumor cells is in intimate relation with metastatic spread of cancer cells involving the associated issues of cellular proliferation and drug responsiveness. This study was aimed to assess the combination of both surface topographies (fiber alignments and different stiffness of the polymeric substrates (poly(l-lactic acid and poly(ε-caprolactone, PLLA and PCL, respectively as well as collagen substrates (coat and gel to elucidate the effect of the cellular morphology on cellular proliferation and drug sensitivities of two different types of breast cancer cells (MDA-MB-231 and MCF-7. The morphological spreading parameter (nucleus/cytoplasm area ratio induced by the anthropogenic substrates has correlated intimately with the cellular proliferation and the drug sensitivity the half maximal inhibitory concentration (IC50 of cancer cells. This study demonstrated the promising results of the parameter for the evaluation of cancer cell malignancy.

  14. The role of cellular proliferation in an experimental model of massive periretinal proliferation

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    Fastenberg, D.M.; Diddie, K.R.; Dorey, K.; Ryan, S.J.

    1982-05-01

    Transplantation of from 10,000 to 750,000 autologous and homologous dermal fibroblasts into the vitreous cavity of rabbit eyes resulted in identical clinical findings leading to massive periretinal proliferation. A dose-response relationship between the number of cells injected and the extent of retinal traction that developed was established. The second phase of the experiment evaluated the effects of formalin and cobalt irradiation on the fibroblasts' ability to cause traction retinal detachment. Cell proliferation or the attainment of a critical mass of living cells was necessary for the development of traction retinal detachment.

  15. Direct electric current modifies important cellular aspects and ultrastructure features of Candida albicans yeasts: Influence of doses and polarities.

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    Barbosa, Gleyce Moreno; Dos Santos, Eldio Gonçalves; Capella, Francielle Neves Carvalho; Homsani, Fortune; de Pointis Marçal, Carina; Dos Santos Valle, Roberta; de Araújo Abi-Chacra, Érika; Braga-Silva, Lys Adriana; de Oliveira Sales, Marcelo Henrique; da Silva Neto, Inácio Domingos; da Veiga, Venicio Feo; Dos Santos, André Luis Souza; Holandino, Carla

    2017-02-01

    Available treatments against human fungal pathogens present high levels of resistance, motivating the development of new antifungal therapies. In this context, the present work aimed to analyze direct electric current (DC) antifungal action, using an in vitro apparatus equipped with platinum electrodes. Candida albicans yeast cells were submitted to three distinct conditions of DC treatment (anodic flow-AF; electroionic flow-EIF; and cathodic flow-CF), as well as different charges, ranging from 0.03 to 2.40 C. Our results indicated C. albicans presented distinct sensibility depending on the DC intensity and polarity applied. Both the colony-forming unit assay and the cytometry flow with propidium iodide indicated a drastic reduction on cellular viability after AF treatment with 0.15 C, while CF- and EIF-treated cells stayed alive when DC doses were increased up to 2.40 C. Additionally, transmission electron microscopy revealed important ultrastructural alterations in AF-treated yeasts, including cell structure disorganization, ruptures in plasmatic membrane, and cytoplasmic rarefaction. This work emphasizes the importance of physical parameters (polarity and doses) in cellular damage, and brings new evidence for using electrotherapy to treat C. albicans pathology process. Bioelectromagnetics. 38:95-108, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  16. 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.

  17. Human Homolog of Drosophila Ariadne (HHARI) is a marker of cellular proliferation associated with nuclear bodies

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    Elmehdawi, Fatima; Wheway, Gabrielle; Szymanska, Katarzyna [Division of Clinical Sciences, Leeds Institute of Molecular Medicine, Level 8, Wellcome Trust Brenner Building, University of Leeds, Leeds, LS9 7TF West Yorkshire (United Kingdom); Adams, Matthew [BioScreening Technology Group, Biomedical Health Research Center, Wellcome Trust Brenner Building, University of Leeds, Leeds, LS9 7TF West Yorkshire (United Kingdom); High, Alec S. [Department of Histopathology, Bexley Wing, St. James' s University Hospital, Beckett Street, Leeds, LS9 7TF West Yorkshire (United Kingdom); Johnson, Colin A., E-mail: c.johnson@leeds.ac.uk [Division of Clinical Sciences, Leeds Institute of Molecular Medicine, Level 8, Wellcome Trust Brenner Building, University of Leeds, Leeds, LS9 7TF West Yorkshire (United Kingdom); Robinson, Philip A. [Division of Clinical Sciences, Leeds Institute of Molecular Medicine, Level 8, Wellcome Trust Brenner Building, University of Leeds, Leeds, LS9 7TF West Yorkshire (United Kingdom)

    2013-02-01

    HHARI (also known as ARIH1) is an ubiquitin-protein ligase and is the cognate of the E2, UbcH7 (UBE2L3). To establish a functional role for HHARI in cellular proliferation processes, we performed a reverse genetics screen that identified n=86/522 (16.5%) ubiquitin conjugation components that have a statistically significant effect on cell proliferation, which included HHARI as a strong hit. We then produced and validated a panel of specific antibodies that establish HHARI as both a nuclear and cytoplasmic protein that is expressed in all cell types studied. HHARI was expressed at higher levels in nuclei, and co-localized with nuclear bodies including Cajal bodies (p80 coilin, NOPP140), PML and SC35 bodies. We confirmed reduced cellular proliferation after ARIH1 knockdown with individual siRNA duplexes, in addition to significantly increased levels of apoptosis, an increased proportion of cells in G2 phase of the cell cycle, and significant reductions in total cellular RNA levels. In head and neck squamous cell carcinoma biopsies, there are higher levels of HHARI expression associated with increased levels of proliferation, compared to healthy control tissues. We demonstrate that HHARI is associated with cellular proliferation, which may be mediated through its interaction with UbcH7 and modification of proteins in nuclear bodies. -- Highlights: ► We produce and validate new antibody reagents for the ubiquitin-protein ligase HHARI. ► HHARI colocalizes with nuclear bodies including Cajal, PML and SC35 bodies. ► We establish new functions in cell proliferation regulation for HHARI. ► Increased HHARI expression associates with squamous cell carcinoma and proliferation.

  18. Ultrastructural Characterization of Turnip Mosaic Virus-Induced Cellular Rearrangements Reveals Membrane-Bound Viral Particles Accumulating in Vacuoles.

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    Wan, Juan; Basu, Kaustuv; Mui, Jeannie; Vali, Hojatollah; Zheng, Huanquan; Laliberté, Jean-François

    2015-12-01

    Positive-strand RNA [(+) RNA] viruses remodel cellular membranes to facilitate virus replication and assembly. In the case of turnip mosaic virus (TuMV), the viral membrane protein 6K2 plays an essential role in endomembrane alterations. Although 6K2-induced membrane dynamics have been widely studied by confocal microscopy, the ultrastructure of this remodeling has not been extensively examined. In this study, we investigated the formation of TuMV-induced membrane changes by chemical fixation and high-pressure freezing/freeze substitution (HPF/FS) for transmission electron microscopy at different times of infection. We observed the formation of convoluted membranes connected to rough endoplasmic reticulum (rER) early in the infection process, followed by the production of single-membrane vesicle-like (SMVL) structures at the midstage of infection. Both SMVL and double-membrane vesicle-like structures with electron-dense cores, as well as electron-dense bodies, were found late in the infection process. Immunogold labeling results showed that the vesicle-like structures were 6K2 tagged and suggested that only the SMVL structures were viral RNA replication sites. Electron tomography (ET) was used to regenerate a three-dimensional model of these vesicle-like structures, which showed that they were, in fact, tubules. Late in infection, we observed filamentous particle bundles associated with electron-dense bodies, which suggests that these are sites for viral particle assembly. In addition, TuMV particles were observed to accumulate in the central vacuole as membrane-associated linear arrays. Our work thus unravels the sequential appearance of distinct TuMV-induced membrane structures for viral RNA replication, viral particle assembly, and accumulation. Positive-strand RNA viruses remodel cellular membranes for different stages of the infection process, such as protein translation and processing, viral RNA synthesis, particle assembly, and virus transmission. The

  19. Increased cellular proliferation in rat skeletal muscle and tendon in response to exercise

    DEFF Research Database (Denmark)

    Skovgaard, Dorthe; Bayer, Monika L; Mackey, Abigail

    2010-01-01

    -derived standardized uptake values were calculated for Achilles tendons and calf muscles and compared to gene expression and immunohistochemical evaluations of Ki67. RESULTS: Treadmill running induced increased uptake of FLT uptake in calf muscles (30%; p ...-derived results were supported by a correlation in calf muscle to Ki67 (protein and mRNA level), while this coherence was not found in tendon. CONCLUSION: FLT-PET seems to be a promising tool for imaging of exercise-induced cellular proliferation in musculo-tendinous tissue.......PURPOSE: The purpose of this study is to investigate exercise-induced cellular proliferation in rat skeletal muscle/tendon with the use of 3'-[F-18]fluoro-3'deoxythymidine (FLT) and to quantitatively study concomitant changes in the proliferation-associated factor, Ki67. PROCEDURES: Wistar rats (n...

  20. Glucose stimulates intestinal epithelial crypt proliferation by modulating cellular energy metabolism.

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    Zhou, Weinan; Ramachandran, Deepti; Mansouri, Abdelhak; Dailey, Megan J

    2018-04-01

    The intestinal epithelium plays an essential role in nutrient absorption, hormone release, and barrier function. Maintenance of the epithelium is driven by continuous cell renewal by stem cells located in the intestinal crypts. The amount and type of diet influence this process and result in changes in the size and cellular make-up of the tissue. The mechanism underlying the nutrient-driven changes in proliferation is not known, but may involve a shift in intracellular metabolism that allows for more nutrients to be used to manufacture new cells. We hypothesized that nutrient availability drives changes in cellular energy metabolism of small intestinal epithelial crypts that could contribute to increases in crypt proliferation. We utilized primary small intestinal epithelial crypts from C57BL/6J mice to study (1) the effect of glucose on crypt proliferation and (2) the effect of glucose on crypt metabolism using an extracellular flux analyzer for real-time metabolic measurements. We found that glucose increased both crypt proliferation and glycolysis, and the glycolytic pathway inhibitor 2-deoxy-d-glucose (2-DG) attenuated glucose-induced crypt proliferation. Glucose did not enhance glucose oxidation, but did increase the maximum mitochondrial respiratory capacity, which may contribute to glucose-induced increases in proliferation. Glucose activated Akt/HIF-1α signaling pathway, which might be at least in part responsible for glucose-induced glycolysis and cell proliferation. These results suggest that high glucose availability induces an increase in crypt proliferation by inducing an increase in glycolysis with no change in glucose oxidation. © 2017 Wiley Periodicals, Inc.

  1. Cellular, ultrastructural and molecular analyses of epidermal cell development in the planarian Schmidtea mediterranea.

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    Cheng, Li-Chun; Tu, Kimberly C; Seidel, Chris W; Robb, Sofia M C; Guo, Fengli; Sánchez Alvarado, Alejandro

    2018-01-15

    The epidermis is essential for animal survival, providing both a protective barrier and cellular sensor to external environments. The generally conserved embryonic origin of the epidermis, but the broad morphological and functional diversity of this organ across animals is puzzling. We define the transcriptional regulators underlying epidermal lineage differentiation in the planarian Schmidtea mediterranea, an invertebrate organism that, unlike fruitflies and nematodes, continuously replaces its epidermal cells. We find that Smed-p53, Sox and Pax transcription factors are essential regulators of epidermal homeostasis, and act cooperatively to regulate genes associated with early epidermal precursor cell differentiation, including a tandemly arrayed novel gene family (prog) of secreted proteins. Additionally, we report on the discovery of distinct and previously undescribed secreted organelles whose production is dependent on the transcriptional activity of soxP-3, and which we term Hyman vesicles. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Ultrastructural studies of time-course and cellular specificity of interleukin-1 mediated islet cytotoxicity

    DEFF Research Database (Denmark)

    Mandrup-Poulsen, T; Egeberg, J; Nerup, J

    1987-01-01

    Previous electron-microscopic studies of isolated islets of Langerhans exposed to the monokine interleukin-1 for 7 days have indicated that interleukin-1 is cytotoxic to all islet cells. To study the time-course and possible cellular specificity of interleukin-1 cytotoxicity to islets exposed...... to interleukin-1 for short time periods, isolated rat or human islets were incubated with or without 25 U/ml highly purified human interleukin-1 for 24 h. Samples of rat islets were taken after 5 min, 30 min, 1, 2, 4, 6, 8, 10, 12, 16, 20 and 24 h and samples of human islets after 5 min, 30 min and 24 h...... of incubation and examined by electron microscopy in a blinded fashion. Already after 30 min, accumulation of opaque intracytoplasmic bodies without apparent surrounding membranes, and autophagic vacuoles were seen in about 20% of the beta cells examined in rat islets exposed to interleukin-1. After 16 h...

  3. Modeling cell adhesion and proliferation: a cellular-automata based approach.

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    Vivas, J; Garzón-Alvarado, D; Cerrolaza, M

    Cell adhesion is a process that involves the interaction between the cell membrane and another surface, either a cell or a substrate. Unlike experimental tests, computer models can simulate processes and study the result of experiments in a shorter time and lower costs. One of the tools used to simulate biological processes is the cellular automata, which is a dynamic system that is discrete both in space and time. This work describes a computer model based on cellular automata for the adhesion process and cell proliferation to predict the behavior of a cell population in suspension and adhered to a substrate. The values of the simulated system were obtained through experimental tests on fibroblast monolayer cultures. The results allow us to estimate the cells settling time in culture as well as the adhesion and proliferation time. The change in the cells morphology as the adhesion over the contact surface progress was also observed. The formation of the initial link between cell and the substrate of the adhesion was observed after 100 min where the cell on the substrate retains its spherical morphology during the simulation. The cellular automata model developed is, however, a simplified representation of the steps in the adhesion process and the subsequent proliferation. A combined framework of experimental and computational simulation based on cellular automata was proposed to represent the fibroblast adhesion on substrates and changes in a macro-scale observed in the cell during the adhesion process. The approach showed to be simple and efficient.

  4. Diffusion kurtosis imaging can efficiently assess the glioma grade and cellular proliferation

    OpenAIRE

    Jiang, Rifeng; Jiang, Jingjing; Zhao, Lingyun; Zhang, Jiaxuan; Zhang, Shun; Yao, Yihao; Yang, Shiqi; Shi, Jingjing; Shen, Nanxi; Su, Changliang; Zhang, Ju; Zhu, Wenzhen

    2015-01-01

    Conventional diffusion imaging techniques are not sufficiently accurate for evaluating glioma grade and cellular proliferation, which are critical for guiding glioma treatment. Diffusion kurtosis imaging (DKI), an advanced non-Gaussian diffusion imaging technique, has shown potential in grading glioma; however, its applications in this tumor have not been fully elucidated. In this study, DKI and diffusion weighted imaging (DWI) were performed on 74 consecutive patients with histopathologicall...

  5. Human papillomavirus type 16 E7 perturbs DREAM to promote cellular proliferation and mitotic gene expression

    OpenAIRE

    DeCaprio, James A.

    2013-01-01

    Study of the small DNA tumor viruses continues to provide valuable new insights into oncogenesis and fundamental biological processes. While much has already been revealed about how the human papillomaviruses (HPVs) can transform cells and contribute to cervical and oropharyngeal cancer, there clearly is much more to learn. In this issue of Oncogene, Pang et al. demonstrate that the high-risk HPV16 E7 oncogene can promote cellular proliferation by interacting with the DREAM (DP, RB-like, E2F ...

  6. CD10/NEP in non-small cell lung carcinomas. Relationship to cellular proliferation.

    OpenAIRE

    Ganju, R K; Sunday, M; Tsarwhas, D G; Card, A; Shipp, M A

    1994-01-01

    The cell surface metalloproteinase CD10/neutral endopeptidase 24.11 (NEP) hydrolyzes a variety of peptide substrates and reduces cellular responses to specific peptide hormones. Because CD10/NEP modulates peptide-mediated proliferation of small cell carcinomas of the lung (SCLC) and normal fetal bronchial epithelium, we evaluated the enzyme's expression in non-small cell lung carcinomas (NSCLC). Bronchoalveolar and large cell carcinoma cell lines had low levels of CD10/NEP expression whereas ...

  7. Selective transcription and cellular proliferation induced by PDGF require histone deacetylase activity

    International Nuclear Information System (INIS)

    Catania, Annunziata; Iavarone, Carlo; Carlomagno, Stella M.; Chiariello, Mario

    2006-01-01

    Histone deacetylases (HDACs) are key regulatory enzymes involved in the control of gene expression and their inhibition by specific drugs has been widely correlated to cell cycle arrest, terminal differentiation, and apoptosis. Here, we investigated whether HDAC activity was required for PDGF-dependent signal transduction and cellular proliferation. Exposure of PDGF-stimulated NIH3T3 fibroblasts to the HDAC inhibitor trichostatin A (TSA) potently repressed the expression of a group of genes correlated to PDGF-dependent cellular growth and pro-survival activity. Moreover, we show that TSA interfered with STAT3-dependent transcriptional activity induced by PDGF. Still, neither phosphorylation nor nuclear translocation and DNA-binding in vitro and in vivo of STAT3 were affected by using TSA to interfere with PDGF stimulation. Finally, TSA treatment resulted in the suppression of PDGF-dependent cellular proliferation without affecting cellular survival of NIH3T3 cells. Our data indicate that inhibition of HDAC activity antagonizes the mitogenic effect of PDGF, suggesting that these drugs may specifically act on the expression of STAT-dependent, PDGF-responsive genes

  8. Proteic expression of p53 and cellular proliferation in oral leukoplakias.

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    Santos-García, Antonio; Abad-Hernández, M Mar; Fonseca-Sánchez, Emilio; Cruz-Hernández, Juan Jesús; Bullón-Sopelana, Agustín

    2005-01-01

    We intend to know the protein expression of genetic alterations that take place in the early stages in the field cancerization of oral cavity in our means as well as to study the cellular proliferation by means of Ki-67 and the protein product expression of p53 to value if the alterations in the protein products expression of these markers happen in a sequential pathway through the different stages in the field cancerization of oral cavity. A study was made by immunohistochemistry on 53 patients that presented lesions of oral leukoplaquia, assisted by the ENT service at University Hospital of Salamanca, from 1.990 up to 2000. 11 samples of normal epithelium, 15 mild to moderate dysplasias, 15 in situ carcinomas and 12 microinvasive carcinomas are included in the study. we find an increased cellular proliferation and p53 over-expression as we advance in the grade of severity histopathologic of these lesions. The most early alterations are a significant increase of cell proliferation in mild and moderate dysplasias and an increased p53 over-expression. Oral leukoplaquia is a precancerous stage that constitutes a cancerisable lesion due to the genetic alterations that mediate in the evolution of lesion. Routine Immunohistochemical and molecular study of these lesions allow us to know the protein expression of genetic alterations that can help in the early diagnosis and treatment of this pathology, having special relevance the study of Ki-67 in early stages and p53 in advanced lesions.

  9. In vivo imaging of cellular proliferation in renal cell carcinoma using 18F-fluorothymidine PET

    International Nuclear Information System (INIS)

    Wong, Peter K.; Lee, Sze Ting; Murone, Carmel; Eng, John; Lawrentschuk, Nathan; Berlangieri, Salvatore University; Pathmaraj, Kunthi; O’Keefe, Graeme J.; Sachinidis, John; Byrne, Amanda J.; Bolton, Damien M.; Davis, Ian D.; Scott, Andrew M.

    2014-01-01

    The ability to measure cellular proliferation non-invasively in renal cell carcinoma may allow prediction of tumour aggressiveness and response to therapy. The aim of this study was to evaluate the uptake of 18F-fluorothymidine (FLT) PET in renal cell carcinoma (RCC), and to compare this to 18F-fluorodeoxyglucose (FDG), and to an immunohistochemical measure of cellular proliferation (Ki-67). Twenty seven patients (16 male, 11 females; age 42-77) with newly diagnosed renal cell carcinoma suitable for resection were prospectively enrolled. All patients had preoperative FLT and FDG PET scans. Visual identification of tumour using FLT PET compared to normal kidney was facilitated by the use of a pre-operative contrast enhanced CT scan. After surgery tumour was taken for histologic analysis and immunohistochemical staining by Ki-67. The SUVmax (maximum standardized uptake value) mean±SD for FLT in tumour was 2.59±1.27, compared to normal kidney (2.47±0.34). The mean SUVmax for FDG in tumour was similar to FLT (2.60±1.08). There was a significant correlation between FLT uptake and the immunohistochemical marker Ki-67 (r=0.72, P<0.0001) in RCC. Ki-67 proliferative index was mean ± SD of 13.3%±9.2 (range 2.2% - 36.3%). There is detectable uptake of FLT in primary renal cell carcinoma, which correlates with cellular proliferation as assessed by Ki-67 labelling index. This finding has relevance to the use of FLT PET in molecular imaging studies of renal cell carcinoma biology

  10. Retinoic acid receptor gamma impacts cellular adhesion, Alpha5Beta1 integrin expression and proliferation in K562 cells.

    Science.gov (United States)

    Kelley, Melissa D; Phomakay, Raynin; Lee, Madison; Niedzwiedz, Victoria; Mayo, Rachel

    2017-01-01

    The interplay between cellular adhesion and proliferation is complex; however, integrins, particularly the α5β1 subset, play a pivotal role in orchestrating critical cellular signals that culminate in cellular adhesion and growth. Retinoids modify the expression of a variety of adhesive/proliferative signaling proteins including α5β1 integrins; however, the role of specific retinoic acid receptors involved in these processes has not been elucidated. In this study, the effect of all-trans-retinoic acid receptor (RAR) agonists on K562 cellular adhesion, proliferation, and α5β1 integrin cell surface expression was investigated. RARγ agonist exposure increased K562 cellular adhesion to RGD containing extracellular matrix proteins fibronectin and FN-120 in a time- and concentration dependent manner, while RARα or RARβ agonist treatment had no effect on cellular adhesion. Due to the novel RARγ- dependent cellular adhesion response exhibited by K562 cells, we examined α5 and β1 integrin subunit expression when K562 cells were exposed to retinoid agonists or vehicle for 24, 48, 72 or 96 hours. Our data demonstrates no differences in K562 cell surface expression of the α5 integrin subunit when cells were exposed to RARα, RARβ, or RARγ agonists for all time points tested. In contrast, RARγ agonist exposure resulted in an increase in cell surface β1 integrin subunit expression within 48 hours that was sustained at 72 and 96 hours. Finally, we demonstrate that while exposure to RARα or RARβ agonists have no effect on K562 cellular proliferation, the RARγ agonist significantly dampens K562 cellular proliferation levels in a time- and concentration- dependent manner. Our study is the first to report that treatment with a RARγ specific agonist augments cellular adhesion to α5β1 integrin substrates, increases cell surface levels of the β1 integrin subunit, and dampens cellular proliferation in a time and concentration dependent manner in a human

  11. Diffusion kurtosis imaging can efficiently assess the glioma grade and cellular proliferation.

    Science.gov (United States)

    Jiang, Rifeng; Jiang, Jingjing; Zhao, Lingyun; Zhang, Jiaxuan; Zhang, Shun; Yao, Yihao; Yang, Shiqi; Shi, Jingjing; Shen, Nanxi; Su, Changliang; Zhang, Ju; Zhu, Wenzhen

    2015-12-08

    Conventional diffusion imaging techniques are not sufficiently accurate for evaluating glioma grade and cellular proliferation, which are critical for guiding glioma treatment. Diffusion kurtosis imaging (DKI), an advanced non-Gaussian diffusion imaging technique, has shown potential in grading glioma; however, its applications in this tumor have not been fully elucidated. In this study, DKI and diffusion weighted imaging (DWI) were performed on 74 consecutive patients with histopathologically confirmed glioma. The kurtosis and conventional diffusion metric values of the tumor were semi-automatically obtained. The relationships of these metrics with the glioma grade and Ki-67 expression were evaluated. The diagnostic efficiency of these metrics in grading was further compared. It was demonstrated that compared with the conventional diffusion metrics, the kurtosis metrics were more promising imaging markers in distinguishing high-grade from low-grade gliomas and distinguishing among grade II, III and IV gliomas; the kurtosis metrics also showed great potential in the prediction of Ki-67 expression. To our best knowledge, we are the first to reveal the ability of DKI to assess the cellular proliferation of gliomas, and to employ the semi-automatic method for the accurate measurement of gliomas. These results could have a significant impact on the diagnosis and subsequent therapy of glioma.

  12. Effect of propolis on mitotic and cellular proliferation indices in human blood lymphocytes

    International Nuclear Information System (INIS)

    Montoro, A.; Almonacid, M.; Villaescusa, J.; Barquinero, J.; Barrios, L.; Verdu, G.; Perez, J.

    2006-01-01

    The study of the frequency of chromosomal aberrations per cell is the tool used in Biological dosimetry studies. Using dose-effect calibration curve obtained in our laboratory, we can evaluate the radioprotector effect of the EEP (ethanolic extract of propolis) in cultures in vitro. Propolis is the generic name for resinous substance collected by honeybees. The results showed a reduction in chromosomal aberrations's frequency of up to 50 %. The following study consisted of analyzing human peripheral blood lymphocytes exposed to 2 Gy γ rays, in presence and absence of EEP, the change in the frequency of chromosome aberrations was analysed with biological dosimetry. The protection against the formation of dicentric and ring was dose-dependent, but there seemed to be a maximum protection, i.e. a further increase in the concentration of EEP does not show additional protection. This work studies the effect of the EEP of the cellular cycle using the mitotic and cellular proliferation index, as an alternative for the screening cytostatic activity. The results indicate that the lymphocytes which were cultures in presence of EEP exhibited a significant and dependent-concentration decrease in mitotic index and proliferation kinetics. The possible mechanisms involved in the radioprotective influence of EEP are discussed. (authors)

  13. Effect of propolis on mitotic and cellular proliferation indices in human blood lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Montoro, A.; Almonacid, M.; Villaescusa, J. [Valencia Hospital Univ. la Fe, Servicio de Proteccion Radiologica (Spain); Barquinero, J. [Barcelona Univ. Autonom, Servicio de Dosimetria Biologica, Unidad de Antropologia, Dept. de Biologia Animal, Vegetal y Ecologia, barcelona (Spain); Barrios, L. [Barcelona Univ. Autonoma, Dept. de Biologia Celular y Fisiologia. Unidad de Biologia Celular (Spain); Verdu, G. [Valencia Univ. Politecnica, Dept. de Ingenieria Quimica y Nuclear (Spain); Perez, J. [Hospital la Fe, Seccion de Radiofisica, Servicio de Radioterapia, valencia (Spain)

    2006-07-01

    The study of the frequency of chromosomal aberrations per cell is the tool used in Biological dosimetry studies. Using dose-effect calibration curve obtained in our laboratory, we can evaluate the radioprotector effect of the EEP (ethanolic extract of propolis) in cultures in vitro. Propolis is the generic name for resinous substance collected by honeybees. The results showed a reduction in chromosomal aberrations's frequency of up to 50 %. The following study consisted of analyzing human peripheral blood lymphocytes exposed to 2 Gy {gamma} rays, in presence and absence of EEP, the change in the frequency of chromosome aberrations was analysed with biological dosimetry. The protection against the formation of dicentric and ring was dose-dependent, but there seemed to be a maximum protection, i.e. a further increase in the concentration of EEP does not show additional protection. This work studies the effect of the EEP of the cellular cycle using the mitotic and cellular proliferation index, as an alternative for the screening cytostatic activity. The results indicate that the lymphocytes which were cultures in presence of EEP exhibited a significant and dependent-concentration decrease in mitotic index and proliferation kinetics. The possible mechanisms involved in the radioprotective influence of EEP are discussed. (authors)

  14. A study of the effect of salicylic acetic acid on a lymphocyte cell model of cellular activation and proliferation.

    Science.gov (United States)

    Aguilar, Enrique Aranda; de la Haba-Rodríguez, Juan; Macho, Antonio; Lucena, Concha; Gómez, Auxiliadora; Calzado, Marco; Muñoz, Eduardo

    2006-01-18

    Salicylic acetic acid (SAA) is a drug that has formed part of the treatment of many diseases for many years. Its anti-inflammatory activity is well known, but recently its possible role in the interference in the oncogenesis mechanisms has become apparent. With the aim of supporting these yet preliminary observations, we studied the effect of salicylic acetic acid on a cellular activation and proliferation model. We used lymphocytes obtained from peripheral blood, which were later exposed to cellular activation and proliferation stimulus by the SEB antigen. Lymphocyte activation was determined by direct immunoflourescence through expression of the receptor IL-2 (CD25) alpha chain and proliferation through the incorporation of tritiated thymidine to the DNA in synthesis together with the determination of the cellular cycle by flow cytometry. We found that both processes, activation and proliferation, are inhibited by increasing doses of SAA.

  15. Immunohistochemical expression of EGFR in oral leukoplakia: Association with clinicopathological features and cellular proliferation

    Science.gov (United States)

    Ribeiro, Daniela C.; Gleber-Netto, Frederico O.; Sousa, Sílvia F.; Bernardes, Vanessa F.; Guimarães-Abreu, Mauro H.N.

    2012-01-01

    Objectives: to investigate the immunoexpression of epidermal growth factor receptor (EGFR) in a sample of oral leukoplakias (OL) and to determine the receptor’s association with dysplasia, tobacco consumption, lesion site, and proliferation rate. Although EGFR should be overexpressed in some oral leukoplakias, the factors that may interfere with this expression and the influence of this receptor on epithelial proliferation have yet to be investigated. Study Design: Samples of oral leukoplakias (48) and of normal oral epithelium (10) were immunohistologically examined for expression of EGFR. Immunohistochemistry for Ki-67, and p27 were also performed in leukoplakias. EGFR expression was associated with clinical and pathological features. Results: EGFR was positive in 62.5% of the leukoplakias and 50% of normal oral epithelium. The number of EGFR positive OL located in high-risk sites was significantly higher than EGFR positive OL located in low-risk sites. Most of the p27 negative leukoplakias were EGFR positive, and the p27 index in the parabasal layer was diminished in the presence of dysplasia. Positivity for EGFR was not associated with dysplasia, tobacco exposure, or Ki-67. Conclusion: EGFR is expressed in leukoplakia regardless of dysplasia, but EGFR positivity should be more frequent in lesions sited in areas of high cancer risk. The association between EGFR and p27 may represent an important mechanism in the control of cellular proliferation and malignant progression of oral epithelium and therefore warrants further investigation. Key words:Oral leukoplakia, EGFR, p27, Ki-67, epithelial dysplasia. PMID:22322523

  16. Rhythmic expressed clock regulates the transcription of proliferating cellular nuclear antigen in teleost retina.

    Science.gov (United States)

    Song, Hang; Wang, Defeng; De Jesus Perez, Felipe; Xie, Rongrong; Liu, Zhipeng; Chen, Chun-Chun; Yu, Meijuan; Yuan, Liudi; Fernald, Russell D; Zhao, Sheng

    2017-07-01

    Teleost fish continues to grow their eyes throughout life with the body size. In Astatotilapia burtoni, the fish retina increases by adding new retinal cells at the ciliary marginal zone (CMZ) and in the outer nuclear layer (ONL). Cell proliferation at both sites exhibits a daily rhythm in number of dividing cells. To understand how this diurnal rhythm of new cell production is controlled in retinal progenitor cells, we studied the transcription pattern of clock genes in retina, including clock1a, clock1b, bmal1a (brain and muscle ARNT-Like), and per1b (period1b). We found that these genes have a strong diurnal rhythmic transcription during light-dark cycles but not in constant darkness. An oscillation in pcna transcription was also observed during light-dark cycles, but again not in constant darkness. Our results also indicate an association between Clock proteins and the upstream region of pcna (proliferating cellular nuclear antigen) gene. A luciferase reporter assay conducted in an inducible clock knockdown cell line further demonstrated that the mutation on predicted E-Boxes in pcna promoter region significantly attenuated the transcriptional activation induced by Clock protein. These results suggested that the diurnal rhythmic expression of clock genes in A. burtoni retina could be light dependent and might contribute to the daily regulation of the proliferation of the retina progenitors through key components of cell cycle machinery, for instance, pcna. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. A genetic and functional relationship between T cells and cellular proliferation in the adult hippocampus.

    Directory of Open Access Journals (Sweden)

    Guo-Jen Huang

    2010-12-01

    Full Text Available Neurogenesis continues through the adult life of mice in the subgranular zone of the dentate gyrus in the hippocampus, but its function remains unclear. Measuring cellular proliferation in the hippocampus of 719 outbred heterogeneous stock mice revealed a highly significant correlation with the proportions of CD8+ versus CD4+ T lymphocyte subsets. This correlation reflected shared genetic loci, with the exception of the H-2Ea locus that had a dominant influence on T cell subsets but no impact on neurogenesis. Analysis of knockouts and repopulation of TCRα-deficient mice by subsets of T cells confirmed the influence of T cells on adult neurogenesis, indicating that CD4+ T cells or subpopulations thereof mediate the effect. Our results reveal an organismal impact, broader than hitherto suspected, of the natural genetic variation that controls T cell development and homeostasis.

  18. Structure and biochemical characterization of proliferating cellular nuclear antigen from a parasitic protozoon

    Energy Technology Data Exchange (ETDEWEB)

    Cardona-Felix, Cesar S.; Lara-Gonzalez, Samuel; Brieba, Luis G. (LNLS)

    2012-02-08

    Proliferating cellular nuclear antigen (PCNA) is a toroidal-shaped protein that is involved in cell-cycle control, DNA replication and DNA repair. Parasitic protozoa are early-diverged eukaryotes that are responsible for neglected diseases. In this work, a PCNA from a parasitic protozoon was identified, cloned and biochemically characterized and its crystal structure was determined. Structural and biochemical studies demonstrate that PCNA from Entamoeba histolytica assembles as a homotrimer that is able to interact with and stimulate the activity of a PCNA-interacting peptide-motif protein from E. histolytica, EhDNAligI. The data indicate a conservation of the biochemical mechanisms of PCNA-mediated interactions between metazoa, yeast and parasitic protozoa.

  19. Human papillomavirus type 16 E7 perturbs DREAM to promote cellular proliferation and mitotic gene expression.

    Science.gov (United States)

    DeCaprio, J A

    2014-07-31

    The study of the small DNA tumor viruses continues to provide valuable new insights into oncogenesis and fundamental biological processes. Although much has already been revealed about how the human papillomaviruses (HPVs) can transform cells and contribute to cervical and oropharyngeal cancer, there clearly is much more to learn. In this issue of Oncogene, Pang et al., doi:10.1038/onc.2013.426, demonstrate that the high-risk HPV16 E7 oncogene can promote cellular proliferation by interacting with the DREAM (DP, RB-like, E2F and MuvB) complex at two distinct phases of the cell cycle. Consistent with earlier work, HPV16 E7 can bind to the retinoblastoma tumor suppressor (RB) family member p130 (RBL2) protein and promote its proteasome-mediated destruction thereby disrupting the DREAM complex and can prevent exit from the cell cycle into quiescence. In addition, they demonstrate that HPV16 E7 can bind to MuvB core complex in association with BMYB and FOXM1 and activate gene expression during the G2 and M phase of the cell cycle. Thus, HPV16 E7 acts to prevent exit from the cell cycle entry and promotes mitotic proliferation and may account for the high levels of FOXM1 often observed in poor-risk cervical cancers.

  20. 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

  1. Residual cellular proliferation on the internal limiting membrane in macular pucker surgery.

    Science.gov (United States)

    Gandorfer, Arnd; Haritoglou, Christos; Scheler, Renate; Schumann, Ricarda; Zhao, Fei; Kampik, Anselm

    2012-03-01

    To provide pathology data on the completeness of epiretinal membrane (ERM) removal with and without internal limiting membrane (ILM) peeling. Twenty-two patients with idiopathic ERM formation underwent vitrectomy with ERM removal and subsequent staining of the vitreomacular interface with brilliant blue. If the ILM was still present after ERM removal, it was peeled off. Both ERM and ILM specimens were harvested in different containers and prepared for flat-mount phase-contrast and interference microscopy, immunocytochemistry, and transmission electron microscopy. In 14 patients (64%), the ILM was still present at the macula after ERM removal. On average, 20% (range, 2-51%) of the total cell count was left behind at the ILM if the ERM was removed only. There were mainly glial cells on the ILM, and few hyalocytes. In nine eyes, the cells were forming cell clusters. In 8 patients (36%), both ERM and ILM were removed together. Electron microscopy showed cellular proliferation directly attached to the ILM in these eyes, whereas in the sequentially peeled group, there was collagen interposed between the ERM and the ILM. Surgical ERM removal resulted in splitting of the vitreous cortex in these eyes, leaving the ILM with residual cells behind. Simple ERM removal results in sufficient separation of fibrocellular tissue in one third of cases, only. In 2 of 3 patients with idiopathic ERM, the vitreous cortex splits when the ERM is removed, leaving an average of 20% of the total cell count behind on the ILM. As these cells are capable of proliferation and causing ERM recurrence, staining of the ILM with subsequent removal seems beneficial in macular pucker surgery.

  2. 9-cis-retinoic Acid and troglitazone impacts cellular adhesion, proliferation, and integrin expression in K562 cells.

    Science.gov (United States)

    Hanson, Amanda M; Gambill, Jessica; Phomakay, Venusa; Staten, C Tyler; Kelley, Melissa D

    2014-01-01

    Retinoids are established pleiotropic regulators of both adaptive and innate immune responses. Recently, troglitazone, a PPAR gamma agonist, has been demonstrated to have anti-inflammatory effects. Separately, retinoids and troglitazone are implicated in immune related processes; however, their combinatory role in cellular adhesion and proliferation has not been well established. In this study, the effect of 9-cis-retinoic acid (9-cis-RA) and troglitazone on K562 cellular adhesion and proliferation was investigated. Troglitazone exposure decreased K562 cellular adhesion to RGD containing extracellular matrix proteins fibronectin, FN-120, and vitronectin in a concentration and time-dependent manner. In the presence of troglitazone, 9-cis-retinoic acid restores cellular adhesion to levels comparable to vehicle treatment alone on fibronectin, FN-120, and vitronectin substrates within 72 hours. Due to the prominent role of integrins in attachment to extracellular matrix proteins, we evaluated the level of integrin α5 subunit expression. Troglitazone treatment results in decrease in α5 subunit expression on the cell surface. In the presence of both agonists, cell surface α5 subunit expression was restored to levels comparable to vehicle treatment alone. Additionally, troglitazone and 9-cis-RA mediated cell adhesion was decreased in the presence of a function blocking integrin alpha 5 inhibitor. Further, through retinoid metabolic profiling and HPLC analysis, our study demonstrates that troglitazone augments retinoid availability in K562 cells. Finally, we demonstrate that troglitazone and 9-cis-retinoic acid synergistically dampen cellular proliferation in K562 cells. Our study is the first to report that the combination of troglitazone and 9-cis-retinoic acid restores cellular adhesion, alters retinoid availability, impacts integrin expression, and dampens cellular proliferation in K562 cells.

  3. Cellular proliferation and regeneration following tissue damage. Progress report. [X radiation; rabbit lenses

    Energy Technology Data Exchange (ETDEWEB)

    Harding, C.V.

    1977-01-01

    Studies were conducted on the following research projects: effects of x radiation on rabbit lenses; DNA synthesis and mitosis in cultured lenses; serum dependency and actinomycin D sensitivity; changes in ultrastructure; injury-induced growth of vascular endothelium; corneal neovascularization following injury; and human cataractous lenses. (HLW)

  4. Hydrolysis of inositol phospholipids precedes cellular proliferation in asbestos-stimulated tracheobronchial epithelial cells

    International Nuclear Information System (INIS)

    Sesko, A.; Mossman, B.; Cabot, M.

    1990-01-01

    Metabolism of inositol phospholipids and phosphatidylcholine was investigated in tracheobronchial epithelial cells exposed to mitogenic concentrations of crocidolite asbestos. Alterations in levels of diacylglycerol, the endogenous activator of protein kinase C, and inositol polyphosphates, presumed mobilizers of intracellular calcium, were examined. Cultures labeled with [ 3 H]diacylglycerol. In contrast, crocidolite-exposed cells labeled with [ 3 H]myristic acid or [ 3 H]choline did not display elevated production of [ 3 H]diacylglycerol or release of [ 3 H]choline metabolites (i.e., evidence of phosphatidylcholine hydrolysis). The soluble tumor promoter phorbol 12-myristate 13-acetate catalyzed both of these changes. myo-[ 3 H]Inositol-labeled cells exposed as briefly as 10 min to mitogenic concentrations of crocidolite demonstrated elevations in [ 3 H]inositol mono-, tris-, and terakisphosphates, phenomena indicating turnover of inositol phospholipids. The detection of diacylglycerol and inositol phosphates in crocidolite asbestos-exposed cells suggests that this fibrous tumor promoter activates phospholipase C as it stimulates cellular proliferation

  5. A dual program for translation regulation in cellular proliferation and differentiation

    DEFF Research Database (Denmark)

    Gingold, Hila; Tehler, Disa; Christoffersen, Nanna R

    2014-01-01

    A dichotomous choice for metazoan cells is between proliferation and differentiation. Measuring tRNA pools in various cell types, we found two distinct subsets, one that is induced in proliferating cells, and repressed otherwise, and another with the opposite signature. Correspondingly, we found ...

  6. Pallial oviduct of Pomacea canaliculata (Gastropoda): ultrastructural studies of the parenchymal cellular types involved in the metabolism of perivitellins.

    Science.gov (United States)

    Catalán, M; Dreon, M S; Heras, H; Pollero, R J; Fernández, S N; Winik, B

    2006-06-01

    Seasonal variations in the morphology of the parenchymal mass and function of the albumen gland/capsule gland complex have been studied in Pomacea canaliculata, together with the cellular types involved in the synthesis and secretion of perivitellin fluid components. The two major parenchymal cell types, albumen secretory cells (AS) and labyrinthic cells (LC), undergo seasonal variations throughout the annual reproductive cycle, which is divided into three periods. Both cellular types show maximal development and structural complexity during the reproductive period (spring and summer). AS cells have a well-developed Golgi complex and rough endoplasmic reticulum and their secretory granules show electron-dense particles of about 20 nm (probably galactogen). These cells are uniquely involved in ovorubin and PV2 perivitellin synthesis and their secretory granules are the single storage site for these two major perivitellins, as revealed by immunoelectron microscopy. AS also possess calcium deposits that infiltrate the cytoplasmic matrix. The luminal surfaces of LC exhibit long cilia intermingled with sparce short microvilli. Basally, the plasma membrane shows deep irregular folds that extend through the cytoplasm up to the subapical region. Calcium deposits infiltrate the cytoplasm and accumulate in the extracellular space of the basal labyrinth. Nerve terminals seem to be involved in the regulation of parenchymal cell secretion. At the post-reproductive period, AS markedly change their aspect following the release of most of the secretory granules into the acinar lumen. LC decrease in volume, the number of their cilia decreases, their cytoplasmic folds are much thinner and their extracellular spaces lack calcium particles. At the pre-reproductive period (winter), AS and LC recover and prepare for the subsequent period.

  7. A novel small compound accelerates dermal wound healing by modifying infiltration, proliferation and migration of distinct cellular components in mice.

    Science.gov (United States)

    Yamaoka, Hanako; Sumiyoshi, Hideaki; Higashi, Kiyoshi; Nakao, Sachie; Minakawa, Kaori; Sumida, Kayo; Saito, Koichi; Ikoma, Norihiro; Mabuchi, Tomotaka; Ozawa, Akira; Inagaki, Yutaka

    2014-06-01

    Impaired wound healing in skin ulcer is one of the major medical issues in the aged society. Wound healing is a complex process orchestrated by a number of humoral factors and cellular components. TGF-β is known to stimulate collagen production in dermal fibroblasts while inhibiting proliferation of epidermal keratinocyte. A screening of small compounds that suppress type I collagen production in fibroblasts has identified HSc025 that antagonizes the TGF-β/Smad signal. We examined the effects of HSc025 on dermal wound healing and elucidated the underlying mechanisms. Effects of HSc025 on the wound closure process were evaluated in a murine full-thickness excisional wound healing model. Cell proliferation and migration were estimated using primary cultures of human keratinocytes and fibroblasts. Comprehensive analyses of gene expression profiles were performed using untreated and HSc025-treated fibroblasts. Oral HSc025 administration suppressed macrophage infiltration and accelerated wound closure as early as at day 2 after the dermal excision. Treatment of cultured keratinocytes with HSc025 counteracted the inhibitory effects of TGF-β on cell proliferation and migration. On the other hand, HSc025 stimulated migration, but not proliferation, of dermal fibroblasts independently of TGF-β. Experiments using an artificial dermis graft revealed that HSc025 stimulated migration of collagen-producing cells into the graft tissue. A cDNA microarray analysis of untreated and HSc025-treated fibroblasts identified pirin as a critical mediator accelerating fibroblast migration. HSc025 accelerates wound healing by modifying infiltration, proliferation and migration of distinct cellular components, which provides a novel insight into the therapy for intractable skin ulcer. Copyright © 2014 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  8. The role of hormones and growth factors in the cellular proliferation control in mammals

    International Nuclear Information System (INIS)

    Armelin, H.A.

    1978-01-01

    A review is done about fibroblast proliferation, its control by classic hormones and hormonal growth factors, showing their main implications and the stage of this research at present. The control exerted on fibronlast proliferation by hormonal growth factors and classic hormones is demonstrated. The existence of basic mechanisms valid for all types of cells is suggested. Experiences are carried out with the aim of finding growth mutants useful in the elucidation of the biochemical mechanisms involved in growth regulation. Radiactive precursors and autoradiographic techniques are used in the research. (M.A.) [pt

  9. Magnolol Affects Cellular Proliferation, Polyamine Biosynthesis and Catabolism-Linked Protein Expression and Associated Cellular Signaling Pathways in Human Prostate Cancer Cells in vitro

    Directory of Open Access Journals (Sweden)

    Brendan T. McKeown

    2015-01-01

    Full Text Available Background: Prostate cancer is the most commonly diagnosed form of cancer in men in Canada and the United States. Both genetic and environmental factors contribute to the development and progression of many cancers, including prostate cancer. Context and purpose of this study: This study investigated the effects of magnolol, a compound found in the roots and bark of the magnolia tree Magnolia officinalis, on cellular proliferation and proliferation-linked activities of PC3 human prostate cancer cells in vitro. Results: PC3 cells exposed to magnolol at a concentration of 80 μM for 6 hours exhibited decreased protein expression of ornithine decarboxylase, a key regulator in polyamine biosynthesis, as well as affecting the expression of other proteins involved in polyamine biosynthesis and catabolism. Furthermore, protein expression of the R2 subunit of ribonucleotide reductase, a key regulatory protein associated with DNA synthesis, was significantly decreased. Finally, the MAPK (mitogen-activated protein kinase, PI3K (phosphatidylinositol 3-kinase, NFκB (nuclear factor of kappa-light-chain-enhancer of activated B cells and AP-1 (activator protein 1 cellular signaling pathways were assayed to determine which, if any, of these pathways magnolol exposure would alter. Protein expressions of p-JNK-1 and c-jun were significantly increased while p-p38, JNK-1/2, PI3Kp85, p-PI3Kp85, p-Akt, NFκBp65, p-IκBα and IκBα protein expressions were significantly decreased. Conclusions: These alterations further support the anti-proliferative effects of magnolol on PC3 human prostate cancer cells in vitro and suggest that magnolol may have potential as a novel anti-prostate cancer agent.

  10. Stem cells distribution, cellular proliferation and migration in the adult Austrolebias charrua brain.

    Science.gov (United States)

    Torres-Pérez, Maximiliano; Rosillo, Juan Carlos; Berrosteguieta, Ines; Olivera-Bravo, Silvia; Casanova, Gabriela; García-Verdugo, José Manuel; Fernández, Anabel Sonia

    2017-10-15

    Our previous studies demonstrated that Austrolebias charrua annual fish is an excellent model to study adult brain cell proliferation and neurogenesis due to the presence of active and fast neurogenesis in several regions during its short lifespan. Our main goal was to identify and localize the cells that compose the neurogenic areas throughout the Austrolebias brain. To do this, we used two thymidine halogenated analogs to detect cell proliferation at different survival times: 5-chloro-2'-deoxyuridine (CldU) at 1day and 5-iodo-2'-deoxyuridine (IdU) at 30days. Three types of proliferating cells were identified: I - transient amplifying or fast cycling cells that uptake CldU; II - stem cells or slow cycling cells, that were labeled with both CldU and IdU and did not migrate; and III - migrant cells that uptake IdU. Mapping and 3D-reconstruction of labeled nuclei showed that type I and type II cells were preferentially found close to ventricle walls. Type III cells appeared widespread and migrating in tangential and radial routes. Use of proliferation markers together with Vimentin or Nestin evidenced that type II cells are the putative stem cells that are located at the ventricular lumen. Double label cells with IdU+ and NeuN or HuC/D allowed us identify migrant neurons. Quantitation of labeled nuclei indicates that the proportion of putative stem cells is around 10% in all regions of the brain. This percentage of stem cells suggests the existence of a constant brain cell population in Austrolebias charrua that seems functional to the maintainance of adult neurogenesis. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Fish oil supplementation associated with decreased cellular degeneration and increased cellular proliferation 6 weeks after middle cerebral artery occlusion in the rat

    Directory of Open Access Journals (Sweden)

    Pascoe MC

    2015-01-01

    Full Text Available Michaela C Pascoe,1 David W Howells, 2David P Crewther,1 Leeanne M Carey,2,3 Sheila G Crewther4 1Brain Sciences Institute, Swinburne University, ²Florey Institute of Neuroscience and Mental Health, University of Melbourne, 3Department of Occupational Therapy, School of Allied Health La Trobe University, 4School of Psychological Science, La Trobe University, Melbourne, VIC, Australia Abstract: Anti-inflammatory long-chain omega-3 polyunsaturated fatty acids (n-3-LC-PUFAs are both neuroprotective and have antidepressive effects. However the influence of dietary supplemented n-3-LC-PUFAs on inflammation-related cell death and proliferation after middle cerebral artery occlusion (MCAo-induced stroke is unknown. We have previously demonstrated that anxiety-like and hyperactive locomotor behaviors are reduced in n-3-LC-PUFA-fed MCAo animals. Thus in the present study, male hooded Wistar rats were exposed to MCAo or sham surgeries and examined behaviorally 6 weeks later, prior to euthanasia and examination of lesion size, cell death and proliferation in the dentate gyrus, cornu ammonis region of the hippocampus of the ipsilesional hemispheres, and the thalamus of the ipsilesional and contralesional hemispheres. Markers of cell genesis and cell degeneration in the hippocampus or thalamus of the ipsilesional hemisphere did not differ between surgery and diet groups 6 weeks post MCAo. Dietary supplementation with n-3-LC-PUFA decreased cell degeneration and increased cell proliferation in the thalamic region of the contralesional hemisphere. MCAo–associated cell degeneration in the hippocampus and thalamus positively correlated with anxiety-like and hyperactive locomotor behaviors previously reported in these animals. These results suggest that anti-inflammatory n-3-LC-PUFA supplementation appears to have cellular protective effects after MCAo in the rat, which may affect behavioral outcomes. Keywords: apoptosis, polyunsaturated fatty acids

  12. Influence of reproductive activity, sex steroids, and seasonality on epigonal organ cellular proliferation in the skate (Leucoraja erinacea).

    Science.gov (United States)

    Lutton, B V; Callard, I P

    2008-01-01

    In elasmobranchs, the epigonal organ, a unique leukopoietic immune tissue, is associated with the gonads. As the ovaries increase in size during reproductive activity, the overall mass of the epigonal organ does not change. However, immunohistochemistry (proliferating cell nuclear antigen Ab) demonstrated more proliferative activity and extravasation of epigonal leukocytes from blood vessels in reproductively active (RA) skates (Leucoraja erinacea) than in non-reproductively active (NRA) skates. In addition, [(3)H]thymidine incorporation was greater in epigonal leukocytes from RA skates than in leukocytes from NRA skates. Plasma from RA skates, but not from NRA skates, increased proliferation of epigonal leukocytes in vitro, an effect that was not seen using steroid-free plasma. In contrast to the stimulatory effect of plasma on leukocyte proliferation, addition of steroids (estrogen, progesterone, testosterone, and dexamethasone) in vitro decreased [(3)H]thymidine incorporation. While the inhibitory response to steroids was seasonally variable, (3)[H]thymidine incorporation was always highest in RA animals, in which plasma steroid levels were also consistently highest. These studies suggest functional interactions between reproductive and immune tissues in the skate, and that cellular turnover in epigonal tissue may be influenced by gonadal activity.

  13. Bufalin Inhibits Cellular Proliferation and Cancer Stem Cell-Like Phenotypes via Upregulation of MiR-203 in Glioma

    Directory of Open Access Journals (Sweden)

    Tao Liu

    2017-11-01

    Full Text Available Background/Aims: Prior studies have shown that bufalin inhibits cellular proliferation and induces apoptosis in various human cancers. MicroRNA-203 (miR-203 has been shown to function as an important regulator of tumor progression at various stages. In this study, we investigated the effect of miR-203 expression and bufalin treatment on glioma cell proliferation and stem cell-like phenotypes. Methods: We used cell viability assay, colony formation assay, cell apoptosis assay and neurosphere formation assay to dectect the treatment effect of bufalin on U251 and U87 cells. Cells were transfected with the miR-203 mimic without bufalin treatment or cells were transfected with anti-miR-203 under bufalin treatment, the above expreiments were repeated. RT-PCR was employed to quantify miR-203 expression. Western blot was performed to detect the stem cell-like (CSC markers, OCT4 and SOX2. Luciferase activity assay was used to determine whether the SPARC is the target of miR-203. Results: Bufalin treatment inhibited cell proliferation, colony formation, and CSC phenotypes and increased cell apoptosis and expression of miR-203. Furthermore, overexpression of miR-203 led to similar outcomes as bufalin treatment with respect to the cell viability, colony formation, cell apoptosis and the phenotypes of glioma cells. While anti-miR-203 attenuated the inhibitory effects of bufalin as promoting cell proliferation, colony formation and CSC phenotyes and inhibiting cell apoptosis. In addition, we identified SPARC as a novel target gene of miR-203. Conclusions: These findings suggest that miR-203 plays an important role in bufalin’s ability to inhibit the growth of glioma cells and the development of stem cell-like phenotypes.

  14. The effects of exposure route on DNA adduct formation and cellular proliferation by 1,2,3-trichloropropane.

    Science.gov (United States)

    La, D K; Schoonhoven, R; Ito, N; Swenberg, J A

    1996-09-01

    1,2,3-Trichloropropane (TCP) induces high incidences of tumors at multiple sites in mice and rats when administered chronically by gavage. The animal tumor data are being used to predict human risk from potential exposure to TCP in drinking water. Risk assessment may be affected by differences in the route of exposure. Gavage administration, which results in high bolus concentrations compared to drinking water exposure, may quantitatively affect toxicokinetics, cytotoxicity, and genotoxicity. We have examined the effects of TCP exposure by the two routes on the formation of DNA adducts and the induction of cellular proliferation. Male B6C3F1 mice were administered [14C]TCP for 1 week by gavage or in drinking water at the low dose (6 mg/kg) used in the NTP carcinogenesis bioassay. Two target organs (forestomach and liver) and two nontarget organs (glandular stomach and kidney) were examined for DNA adduct formation. Adducts were hydrolyzed from DNA, isolated by HPLC, and quantitated by measuring HPLC fractions for radioactivity. In the forestomach, liver, and kidney, gavage administration of TCP resulted in 1.4-to 2.4-fold greater yields of the major DNA adduct, previously identified as S-[1-(hydroxymethyl)-2-(N7-guanyl)ethyl]glutathione. Significant differences in cell proliferation, as determined by incorporation of bromodeoxyuridine into DNA, were also observed for the two routes. Gavage administration of TCP for 2 weeks resulted in up to a threefold greater cell proliferation rate relative to administration in drinking water. Our findings of exposure-related differences in TCP-induced DNA adduct formation and cell proliferation suggest that a risk assessment based on the existing gavage study may overestimate human risk.

  15. Proteomic and Metabolomic Characterization of a Mammalian Cellular Transition from Quiescence to Proliferation.

    Science.gov (United States)

    Lee, Ho-Joon; Jedrychowski, Mark P; Vinayagam, Arunachalam; Wu, Ning; Shyh-Chang, Ng; Hu, Yanhui; Min-Wen, Chua; Moore, Jodene K; Asara, John M; Lyssiotis, Costas A; Perrimon, Norbert; Gygi, Steven P; Cantley, Lewis C; Kirschner, Marc W

    2017-07-18

    There exist similarities and differences in metabolism and physiology between normal proliferative cells and tumor cells. Once a cell enters the cell cycle, metabolic machinery is engaged to facilitate various processes. The kinetics and regulation of these metabolic changes have not been properly evaluated. To correlate the orchestration of these processes with the cell cycle, we analyzed the transition from quiescence to proliferation of a non-malignant murine pro-B lymphocyte cell line in response to IL-3. Using multiplex mass-spectrometry-based proteomics, we show that the transition to proliferation shares features generally attributed to cancer cells: upregulation of glycolysis, lipid metabolism, amino-acid synthesis, and nucleotide synthesis and downregulation of oxidative phosphorylation and the urea cycle. Furthermore, metabolomic profiling of this transition reveals similarities to cancer-related metabolic pathways. In particular, we find that methionine is consumed at a higher rate than that of other essential amino acids, with a potential link to maintenance of the epigenome. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  16. Proteomic and Metabolomic Characterization of a Mammalian Cellular Transition from Quiescence to Proliferation

    Directory of Open Access Journals (Sweden)

    Ho-Joon Lee

    2017-07-01

    Full Text Available There exist similarities and differences in metabolism and physiology between normal proliferative cells and tumor cells. Once a cell enters the cell cycle, metabolic machinery is engaged to facilitate various processes. The kinetics and regulation of these metabolic changes have not been properly evaluated. To correlate the orchestration of these processes with the cell cycle, we analyzed the transition from quiescence to proliferation of a non-malignant murine pro-B lymphocyte cell line in response to IL-3. Using multiplex mass-spectrometry-based proteomics, we show that the transition to proliferation shares features generally attributed to cancer cells: upregulation of glycolysis, lipid metabolism, amino-acid synthesis, and nucleotide synthesis and downregulation of oxidative phosphorylation and the urea cycle. Furthermore, metabolomic profiling of this transition reveals similarities to cancer-related metabolic pathways. In particular, we find that methionine is consumed at a higher rate than that of other essential amino acids, with a potential link to maintenance of the epigenome.

  17. The inflammatory microenvironment of the aging prostate facilitates cellular proliferation and hypertrophy.

    Science.gov (United States)

    Begley, L A; Kasina, S; MacDonald, J; Macoska, J A

    2008-08-01

    Benign Prostatic Hypertrophy (BPH, also known as benign prostatic hyperplasia or benign prostatic enlargement), is one of the most common benign proliferative conditions associated with aging in men and is pathologically characterized by the proliferation of fibroblast/myofibroblast and epithelial cell types in the prostate. Previous studies from our laboratory have shown that the CXC-type chemokines, CXCL5 and CXCL12, are secreted by aging prostate stroma and promote both proliferative and transcriptional responses from prostate epithelial cells. Using array-based gene expression profiling and quantitative reverse-transcriptase polymerase chain reaction, we now show that the transcriptome of the aging prostate stroma is characterized by the up-regulation of several genes that encode secreted inflammatory mediators, including secreted CXC-type chemokines (CXCL1, CXCL2, CXCL5, CXCL6, CXCL12), interleukins (IL11, IL33), and transcripts with cytokine homology (CYTL1). At the protein level, ELISA experiments demonstrated that CXCL1, CXCL5, and CXCL6 were secreted by primary prostate stromal fibroblasts explanted from aging prostate stroma. Dose-response assays confirmed that, like CXCL5 and CXCL12, CXCL1 and CXCL6 promote low-level proliferative responses from both prostate stromal fibroblasts and epithelial cells. Taken together, these data suggest that inflammatory mediators are secreted by prostatic stroma consequent to aging, that the levels of these mediators are sufficient to promote low-level increases in the proliferative rate of both epithelial and stromal fibroblast cell types. Moreover, these processes may account for the low-level, but cumulative, proliferation of both epithelial and fibroblastic/myofibroblastic cell types that characterizes the aging-associated development of benign prostatic hypertophy.

  18. Effects of nicotine on cellular proliferation, cell cycle phase distribution, and macromolecular synthesis in human promyelocytic HL-60 leukaemia cells

    International Nuclear Information System (INIS)

    Konno, S.; Wu, J.M.; Chiao, J.W.

    1986-01-01

    Addition of nicotine causes a dose- and time-dependent inhibition of cell growth in the human promyelocytic HL-60 leukemia cells, with 4 mM nicotine resulting in a 50% inhibition of cellular proliferation after 48-50h. Accompanying the anticellular effect of nicotine is a significant change in the cell cycle distribution of HL-60 cells. For example, treatment with 4 mM nicotine for 20h causes an increase in the proportion of G1-phase cells (from 49% to 57%) and a significant decrease in the proportion of S-phase cells (from 41% to 32%). These results suggest that nicotine causes partial cell arrest in the G-1 phase which may in part account for its effects on cell growth. To determine whether nicotine changes the cellular uptake/transport to macromolecular precursors, HL-60 cells were treated with 216 mM nicotine for 30h, at the end of which time cells were labelled with ( 3 H)thymidine, ( 3 H)uridine, ( 14 C)lysine and( 35 S)methionine, the trichloroacetic acid soluble and insoluble radioactivities from each of the labelling conditions were determined. These studies show that nicotine mainly affects the ''de novo synthesis'' of proteins. (author)

  19. Tensin2 is a novel mediator in thrombopoietin (TPO)-induced cellular proliferation by promoting Akt signaling.

    Science.gov (United States)

    Jung, Andre Scott; Kaushansky, Alexis; Macbeath, Gavin; Kaushansky, Kenneth

    2011-06-01

    Thrombopoietin (TPO) and its receptor c-Mpl are essential in the regulation of the hematopoietic stem and progenitors cells as well as for the differentiation of megakaryocytes into mature platelets. Once TPO binds to its receptor, an intracellular signaling process is initiated through Janus kinase (JAK-2)-induced phosphorylation of the c-Mpl intracellular domain. Although some protein mediators that transmit the effects of TPO have been identified, many remain undiscovered. Using an unbiased approach with peptide microarrays that contained virtually every Src Homology (SH)2 and Phosphotyrosine Binding (PTB) domains in the human genome, we discovered a previously unreported interaction between c-Mpl at phospho-Tyrosine631 (pY 631) and Tensin2, a protein for which limited information is available. Confirming the findings of the microarrays, we discovered that Tensin2 co-precipitates with a pY 631 bearing peptide. Furthermore, we found that Tensin2 becomes phosphorylated in a TPO dependent manner. The functional consequence of Tensin2 was tested via knockdown of Tensin2, which dramatically decreased TPO-dependent cellular proliferation of UT7-TPO cell line as well as their activation of Akt signaling. These studies affirm the use of these arrays as an unbiased screening tool of protein-protein interactions. We conclude that Tensin2 is an important new mediator in TPO/c-Mpl pathway and has a positive affect on cellular growth, at least in part through its effect on the PI3K/Akt signaling.

  20. BRCA1 haploinsufficiency leads to altered expression of genes involved in cellular proliferation and development.

    Directory of Open Access Journals (Sweden)

    Harriet E Feilotter

    Full Text Available The assessment of BRCA1 and BRCA2 coding sequences to identify pathogenic mutations associated with inherited breast/ovarian cancer syndrome has provided a method to identify high-risk individuals, allowing them to seek preventative treatments and strategies. However, the current test is expensive, and cannot differentiate between pathogenic variants and those that may be benign. Focusing only on one of the two BRCA partners, we have developed a biological assay for haploinsufficiency of BRCA1. Using a series of EBV-transformed cell lines, we explored gene expression patterns in cells that were BRCA1 wildtype compared to those that carried (heterozygous BRCA1 pathogenic mutations. We identified a subset of 43 genes whose combined expression pattern is a sensitive predictor of BRCA1 status. The gene set was disproportionately made up of genes involved in cellular differentiation, lending credence to the hypothesis that single copy loss of BRCA1 function may impact differentiation, rendering cells more susceptible to undergoing malignant processes.

  1. Ultrastructural and metabolic changes in osteoblasts exposed to uranyl nitrate

    Energy Technology Data Exchange (ETDEWEB)

    Tasat, D.R. [Universidad Nacional de San Martin, Escuela de Ciencia y Tecnologia, Pcia de Bs.As. (Argentina); Universidad de Buenos Aires, Catedra de Histologia y Embriologia, Facultad de Odontologia, Buenos Aires (Argentina); Orona, N.S. [Universidad Nacional de San Martin, Escuela de Ciencia y Tecnologia, Pcia de Bs.As. (Argentina); Mandalunis, P.M. [Universidad de Buenos Aires, Catedra de Histologia y Embriologia, Facultad de Odontologia, Buenos Aires (Argentina); Cabrini, R.L. [Comision Nacional de Energia Atomica, Departamento de Radiobiologia, Buenos Aires (Argentina); Ubios, A.M. [Comision Nacional de Energia Atomica, Departamento de Radiobiologia, Buenos Aires (Argentina); Universidad de Buenos Aires, Catedra de Histologia y Embriologia, Facultad de Odontologia, Buenos Aires (Argentina)

    2007-05-15

    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 {mu}M) 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 {mu}M 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 {mu}M 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.)

  2. Constitutively active erythropoietin receptor expression in breast cancer cells promotes cellular proliferation and migration through a MAP-kinase dependent pathway

    International Nuclear Information System (INIS)

    Fu Ping; Jiang Xiaohong; Arcasoy, Murat O.

    2009-01-01

    The role of erythropoietin receptor (EpoR) expression in tumor cells and the potential of EpoR-mediated signaling to contribute to cellular proliferation and invasiveness require further characterization. To determine whether EpoR expression and activation in tumor cells modulates intracellular signal transduction to promote cellular proliferation and migration, we employed a novel experimental model using human breast cancer cells engineered to stably express a constitutively active EpoR-R129C variant. EpoR-R129C expression resulted in increased cellular proliferation and migration of breast cancer cells and these effects were associated with significantly increased Epo-induced phosphorylation of ERK1/2, AKT and c-Jun-NH2-kinase (SAPK/JNK) proteins. Expression of the constitutively active EpoR-R129C receptor promoted the proliferation and migration of breast cancer cells via activation of ERK- and SAPK/JNK-dependent signaling pathways, respectively. These findings suggest that EpoR over-expression and activation in breast cancer cells has the potential to contribute to tumor progression by promoting the proliferation and invasiveness of the neoplastic cells.

  3. Comparison of the colony formation and crystal violet cell proliferation assays to determine cellular radiosensitivity in a repair-deficient MCF10A cell line

    Energy Technology Data Exchange (ETDEWEB)

    Vandersickel, Veerle [Department of Basic Medical Sciences, Ghent University, Campus Heymans, De Pintelaan 185 (6B3), 9000 Gent (Belgium); Slabbert, Jacobus [NRF iThemba LABS (Laboratory for Accelerated Based Sciences), PO box 722, 7129 Somerset West (South Africa); Thierens, Hubert [Department of Basic Medical Sciences, Ghent University, Campus Heymans, De Pintelaan 185 (6B3), 9000 Gent (Belgium); Vral, Anne, E-mail: anne.Vral@UGent.b [Department of Basic Medical Sciences, Ghent University, Campus Heymans, De Pintelaan 185 (6B3), 9000 Gent (Belgium)

    2011-01-15

    Colony formation as measured by the in vitro clonogenic assay is a very important endpoint to determine cellular radiosensitivity and tumor response to radiotherapy. In the framework of assessing in vitro cellular radiosensitivity, proliferation assays could represent an attractive alternative to the clonogenic assay for cell lines that do not form proper colonies. In the present study, we compared cellular radiosensitivity measurements obtained by the crystal violet (CV) cell proliferation assay and the standard colony formation assay in repair-deficient and-proficient human MCF10A cell lines. Compared to the clonogenic assay, the CV cell proliferation assay yielded higher surviving fractions for the same radiation dose. This is reflected in larger mean inactivation dose values - a parameter that reflects the area under the survival curve. However, as the dose modifying factors obtained by both assays are comparable, the CV cell proliferation assay can be used to compare the in vitro cellular radiosensitivity of cell lines that lack the ability to form well-defined colonies.

  4. Effects of nicotine on cellular proliferation, macromolecular synthesis and cell cycle phase distribution in human and murine cells

    International Nuclear Information System (INIS)

    Konno, S.; Chiao, J.; Rossi, J.; Wang, C.H.; Wu, J.M.

    1986-01-01

    Addition of nicotine causes a dose- and time-dependent inhibition of cell growth in established human and murine cells. In the human promyelocytic HL-60 leukemic cells, 3 mM nicotine results in a 50% inhibition of cellular proliferation after 80 h. Nicotine was also found to affect the cell cycle distribution of HL-60 cells. Treatment with 4 mM nicotine for 20 h causes an increase in proportion of Gl-phase cells (from 49% to 57%) and a significant decrease in the proportion of S-phase cells (from 41% to 32%). These results suggest that nicotine causes cell arrest in the Gl-phase which may in part account for its effects on cell growth. To determine whether nicotine has a primary effect on the uptake/transport of macromolecular precursors into cells, HL-60 cells were treated with 2-6 mM nicotine for 30 h 3 at the end of which time cells were labeled with [ 3 H]thymidine, [ 3 H]uridine, [ 14 C]lysine and [ 35 S]methionine, the trichloroacetic acid (TCA) soluble and insoluble radioactivities from each of the labeling conditions were determined. These studies show that nicotine primarily affect the synthesis of proteins

  5. CD147 and AGR2 expression promote cellular proliferation and metastasis of head and neck squamous cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Sweeny, Larissa, E-mail: larissasweeny@gmail.com [Department of Surgery, University of Alabama, Division of Otolaryngology-Head and Neck Surgery, 1670 University Boulevard, Volker Hall G082, Birmingham, Alabama (United States); Liu, Zhiyong; Bush, Benjamin D.; Hartman, Yolanda [Department of Surgery, University of Alabama, Division of Otolaryngology-Head and Neck Surgery, 1670 University Boulevard, Volker Hall G082, Birmingham, Alabama (United States); Zhou, Tong [Department of Medicine, Division of Immunology and Rheumatology, 1825 University Boulevard, Shelby Biomedical Research Building 302, Birmingham, Alabama (United States); Rosenthal, Eben L., E-mail: oto@uab.edu [Department of Surgery, University of Alabama, Division of Otolaryngology-Head and Neck Surgery, 1670 University Boulevard, Volker Hall G082, Birmingham, Alabama (United States)

    2012-08-15

    The signaling pathways facilitating metastasis of head and neck squamous cell carcinoma (HNSCC) cells are not fully understood. CD147 is a transmembrane glycoprotein known to induce cell migration and invasion. AGR2 is a secreted peptide also known to promote cell metastasis. Here we describe their importance in the migration and invasion of HNSCC cells (FADU and OSC-19) in vitro and in vivo. In vitro, knockdown of CD147 or AGR2 decreased cellular proliferation, migration and invasion. In vivo, knockdown of CD147 or AGR2 expression decreased primary tumor growth as well as regional and distant metastasis. -- Highlights: Black-Right-Pointing-Pointer We investigated AGR2 in head and neck squamous cell carcinoma for the first time. Black-Right-Pointing-Pointer We explored the relationship between AGR2 and CD147 for the first time. Black-Right-Pointing-Pointer AGR2 and CD147 appear to co-localize in head and squamous cell carcinoma samples. Black-Right-Pointing-Pointer Knockdown of both AGR2 and CD147 reduced migration and invasion in vitro. Black-Right-Pointing-Pointer Knockdown of both AGR2 and CD147 decreased metastasis in vivo.

  6. Susceptibility of Phytomonas serpens to calpain inhibitors in vitro: interference on the proliferation, ultrastructure, cysteine peptidase expression and interaction with the invertebrate host

    Directory of Open Access Journals (Sweden)

    Simone Santiago Carvalho de Oliveira

    Full Text Available A pleiotropic response to the calpain inhibitor MDL28170 was detected in the tomato parasite Phytomonas serpens. Ultrastructural studies revealed that MDL28170 caused mitochondrial swelling, shortening of flagellum and disruption of trans Golgi network. This effect was correlated to the inhibition in processing of cruzipain-like molecules, which presented an increase in expression paralleled by decreased proteolytic activity. Concomitantly, a calcium-dependent cysteine peptidase was detected in the parasite extract, the activity of which was repressed by pre-incubation of parasites with MDL28170. Flow cytometry and Western blotting analyses revealed the differential expression of calpain-like proteins (CALPs in response to the pre-incubation of parasites with the MDL28170, and confocal fluorescence microscopy confirmed their surface location. The interaction of promastigotes with explanted salivary glands of the insect Oncopeltus fasciatus was reduced when parasites were pre-treated with MDL28170, which was correlated to reduced levels of surface cruzipain-like and gp63-like molecules. Treatment of parasites with anti-Drosophila melanogaster (Dm calpain antibody also decreased the adhesion process. Additionally, parasites recovered from the interaction process presented higher levels of surface cruzipain-like and gp63-like molecules, with similar levels of CALPs cross-reactive to anti-Dm-calpain antibody. The results confirm the importance of exploring the use of calpain inhibitors in studying parasites’ physiology.

  7. Susceptibility of Phytomonas serpens to calpain inhibitors in vitro: interference on the proliferation, ultrastructure, cysteine peptidase expression and interaction with the invertebrate host.

    Science.gov (United States)

    Oliveira, Simone Santiago Carvalho de; Gonçalves, Diego de Souza; Garcia-Gomes, Aline Dos Santos; Gonçalves, Inês Correa; Seabra, Sergio Henrique; Menna-Barreto, Rubem Figueiredo; Lopes, Angela Hampshire de Carvalho Santos; D'Avila-Levy, Claudia Masini; Santos, André Luis Souza Dos; Branquinha, Marta Helena

    2017-01-01

    A pleiotropic response to the calpain inhibitor MDL28170 was detected in the tomato parasite Phytomonas serpens. Ultrastructural studies revealed that MDL28170 caused mitochondrial swelling, shortening of flagellum and disruption of trans Golgi network. This effect was correlated to the inhibition in processing of cruzipain-like molecules, which presented an increase in expression paralleled by decreased proteolytic activity. Concomitantly, a calcium-dependent cysteine peptidase was detected in the parasite extract, the activity of which was repressed by pre-incubation of parasites with MDL28170. Flow cytometry and Western blotting analyses revealed the differential expression of calpain-like proteins (CALPs) in response to the pre-incubation of parasites with the MDL28170, and confocal fluorescence microscopy confirmed their surface location. The interaction of promastigotes with explanted salivary glands of the insect Oncopeltus fasciatus was reduced when parasites were pre-treated with MDL28170, which was correlated to reduced levels of surface cruzipain-like and gp63-like molecules. Treatment of parasites with anti-Drosophila melanogaster (Dm) calpain antibody also decreased the adhesion process. Additionally, parasites recovered from the interaction process presented higher levels of surface cruzipain-like and gp63-like molecules, with similar levels of CALPs cross-reactive to anti-Dm-calpain antibody. The results confirm the importance of exploring the use of calpain inhibitors in studying parasites' physiology.

  8. Spindle assembly checkpoint protein expression correlates with cellular proliferation and shorter time to recurrence in ovarian cancer.

    LENUS (Irish Health Repository)

    McGrogan, Barbara

    2014-07-01

    Ovarian carcinoma (OC) is the most lethal of the gynecological malignancies, often presenting at an advanced stage. Treatment is hampered by high levels of drug resistance. The taxanes are microtubule stabilizing agents, used as first-line agents in the treatment of OC that exert their apoptotic effects through the spindle assembly checkpoint. BUB1-related protein kinase (BUBR1) and mitotic arrest deficient 2 (MAD2), essential spindle assembly checkpoint components, play a key role in response to taxanes. BUBR1, MAD2, and Ki-67 were assessed on an OC tissue microarray platform representing 72 OC tumors of varying histologic subtypes. Sixty-one of these patients received paclitaxel and platinum agents combined; 11 received platinum alone. Overall survival was available for all 72 patients, whereas recurrence-free survival (RFS) was available for 66 patients. Increased BUBR1 expression was seen in serous carcinomas, compared with other histologies (P = .03). Increased BUBR1 was significantly associated with tumors of advanced stage (P = .05). Increased MAD2 and BUBR1 expression also correlated with increased cellular proliferation (P < .0002 and P = .02, respectively). Reduced MAD2 nuclear intensity was associated with a shorter RFS (P = .03), in ovarian tumors of differing histologic subtype (n = 66). In this subgroup, for those women who received paclitaxel and platinum agents combined (n = 57), reduced MAD2 intensity also identified women with a shorter RFS (P < .007). For the entire cohort of patients, irrespective of histologic subtype or treatment, MAD2 nuclear intensity retained independent significance in a multivariate model, with tumors showing reduced nuclear MAD2 intensity identifying patients with a poorer RFS (P = .05).

  9. Effects of different transferrin forms on transferrin receptor expression, iron uptake, and cellular proliferation of human leukemic HL60 cells. Mechanisms responsible for the specific cytotoxicity of transferrin-gallium.

    OpenAIRE

    Chitambar, C R; Seligman, P A

    1986-01-01

    We have previously shown that human leukemic cells proliferate normally in serum-free media containing various transferrin forms, but the addition of transferrin-gallium leads to inhibition of cellular proliferation. Because gallium has therapeutic potential, the effects of transferrin-gallium on leukemic cell proliferation, transferrin receptor expression, and cellular iron utilization were studied. The cytotoxicity of gallium is considerably enhanced by its binding to transferrin and cytoto...

  10. NOX5-L can stimulate proliferation and apoptosis depending on its levels and cellular context, determining cancer cell susceptibility to cisplatin

    Science.gov (United States)

    Kwon, Eun-Soo; Lim, Jae Cheong; Park, Sung Sup; Kwon, Ki-Sun

    2015-01-01

    The NADPH oxidase, NOX5, is known to stimulate cell proliferation in some cancers by generating reactive oxygen species (ROS). We show here that the long form of NOX5 (NOX5-L) also promotes cell death, and thus determines the balance of proliferation and death, in skin, breast and lung cancer cells. Moderate expression of NOX5-L induced cell proliferation accompanied by AKT and ERK phosphorylation, whereas an increase in NOX5-L above a certain threshold promoted cancer cell death accompanied by caspase-3 activation. Notably, cisplatin treatment increased NOX5-L levels through CREB activation and enhanced NOX5-L activity through augmentation of Ca2+ release and c-Abl expression, ultimately triggering ROS-mediated cancer cell death—a distinct pathway absent in normal cells. These results indicate that NOX5-L determines cellular responses in a concentration- and context-dependent manner. PMID:26513170

  11. Changes in ATP, glucose-6-phosphate and NAD(P)H cellular levels during the proliferation and maturation phases of Abies alba Mill. embryogenic cultures.

    Science.gov (United States)

    Krajnáková, Jana; Bertolini, Alberto; Zoratti, Laura; Gömöry, Dusan; Häggman, Hely; Vianello, Angelo

    2013-10-01

    The aim of the present study was to evaluate the adenosine triphospate (ATP), glucose-6-phosphate (glu-6P) and reduced form of nicotinamide adenine dinucleotide phosphate (NAD(P)H) cellular levels during the proliferation and maturation phases of Abies alba Mill. somatic embryos. For a better understanding of the dynamics of these parameters during the proliferation cycle, four embryonic cell lines were tested. During the maturation period, three independent experiments were conducted, focused on the effects of PEG-4000 (5 or 10% (w/v)) and abscisic acid (16, 32 or 64 μM) applied together (Experiments A and B) or with addition of gibberellic acid (Experiment C) on the dynamics of bio-energetic molecules and on the mean number of cotyledonary somatic embryos. Our results demonstrated that the cellular levels of bio-energetic molecules strongly depended on the composition of maturation media. Generally, the higher the number of cotyledonary embryos produced, the higher the level of ATP observed after a 2-week maturation period. The cellular level of ATP, glu-6P and NAD(P)H increased, particularly after the transition from the proliferation to the maturation phase when the differentiation and growth of somatic embryos occurred.

  12. Cellular uptake of 99mTcN-NOET in human leukaemic HL-60 cells is related to calcium channel activation and cell proliferation

    International Nuclear Information System (INIS)

    Guillermet, Stephanie; Vuillez, Jean-Philippe; Caravel, Jean-Pierre; Marti-Batlle, Daniele; Fagret, Daniel; Fontaine, Eric; Pasqualini, Roberto

    2006-01-01

    A major goal of nuclear oncology is the development of new radiolabelled tracers as proliferation markers. Intracellular calcium waves play a fundamental role in the course of the cell cycle. These waves occur in non-excitable tumour cells via store-operated calcium channels (SOCCs). Bis(N-ethoxy, N-ethyldithiocarbamato) nitrido technetium (V)-99m ( 99m TcN-NOET) has been shown to interact with L-type voltage-operated calcium channels (VOCCs) in cultured cardiomyocytes. Considering the analogy between VOCCs and SOCCs, we sought to determine whether 99m TcN-NOET also binds to activated SOCCs in tumour cells in order to clarify the potential value of this tracer as a proliferation marker. Uptake kinetics of 99m TcN-NOET were measured in human leukaemic HL-60 cells over 60 min and the effect of several calcium channel modulators on 1-min tracer uptake was studied. The uptake kinetics of 99m TcN-NOET were compared both with the variations of cytosolic free calcium concentration measured by indo-1/AM and with the variations in the SG 2 M cellular proliferation index. All calcium channel inhibitors significantly decreased the cellular uptake of 99m TcN-NOET whereas the activator thapsigargin induced a significant 10% increase. In parallel, SOCC activation by thapsigargin, as measured using the indo-1/AM probe, was inhibited by nicardipine. These results indicate that the uptake of 99m TcN-NOET is related to the activation of SOCCs. Finally, a correlation was observed between the tracer uptake and variations in the proliferation index SG 2 M. The uptake of 99m TcN-NOET seems to be related to SOCC activation and to cell proliferation in HL-60 cells. These results indicate that 99m TcN-NOET might be a marker of cell proliferation. (orig.)

  13. Evaluation of the radioprotective and curative role of a natural antioxidant against cellular ultrastructural hazards induced in rats by gamma radiation exposure

    International Nuclear Information System (INIS)

    Abdel-Azeem, M.G.

    2005-01-01

    This study was designed to investigate the effects of Nigella sativa known as black seed in the amelioration of the histological disorders that occur in different tissues of albino rats exposed to 8 Gy whole body gamma irradiation, delivered as a single dose. Nigella sativa oil was administered daily to rats at a dose of 30 mg / 100 g body weight by gavage, 10 days before irradiation and to another group 10 days after irradiation. Experimental investigations performed one day after radiation for the first group and ten days after radiation for the second group showed that Nigella sativa treatment exerted a radioprotective and curative role on the fine structure of the renal tissue detected as swelling and cristalysis of mitochondria, fragmentation and dilatation damage in the rough endoplasmic reticulum which exhibited in various degrees such as active lysosomes, irregular nuclear membrane, clumped marginal chromatin, pyknotic nucleus with abnormal brush border, absence of infolding and irregularity of basement membrane. Moreover, the radiated hepatic cells showed dilation and thickness in membrane of blood sinasoid as well as lysis of cytoplasmic matrix. Treatment of rats with Nigella sativa during 10 consecutive days either before or after exposure to 8 Gy single dose led to partial improvement of hepatic and kidney cells.The results of the current study indicated that Nigella sativa oil exerted an important protective and curative role against radiation-induced damage in the ultrastructure configuration of kidney and liver cells

  14. Influence of cellular ERalpha/ERbeta ratio on the ERalpha-agonist induced proliferation of human T47D breast cancer cells.

    Science.gov (United States)

    Sotoca, Ana M Covaleda; van den Berg, Hans; Vervoort, Jacques; van der Saag, Paul; Ström, Anders; Gustafsson, Jan-Ake; Rietjens, Ivonne; Murk, Albertinka J

    2008-10-01

    Breast cancer cells show overexpression of estrogen receptor (ER) alpha relative to ERbeta compared to normal breast tissues. This observation has lead to the hypothesis that ERbeta may modulate the proliferative effect of ERalpha. This study investigated how variable cellular expression ratios of the ERalpha and ERbeta modulate the effects on cell proliferation induced by ERalpha or ERbeta agonists, respectively. Using human osteosarcoma (U2OS) ERalpha or ERbeta reporter cells, propyl-pyrazole-triol (PPT) was shown to be a selective ERalpha and diarylpropionitrile (DPN) a preferential ERbeta modulator. The effects of these selective estrogen receptor modulators (SERMs) and of the model compound E2 on the proliferation of T47D human breast cancer cells with tetracycline-dependent expression of ERbeta (T47D-ERbeta) were characterized. E2-induced cell proliferation of cells in which ERbeta expression was inhibited was similar to that of the T47D wild-type cells, whereas this E2-induced cell proliferation was no longer observed when ERbeta expression in the T47D-ERbeta cells was increased. In the T47D-ERbeta cell line, DPN also appeared to be able to suppress cell proliferation when levels of ERbeta expression were high. In the T47D-ERbeta cell line, PPT was unable to suppress cell proliferation at all ratios of ERalpha/ERbeta expression, reflecting its ability to activate only ERalpha and not ERbeta. It is concluded that effects of estrogen-like compounds on cell proliferation are dependent on the actual ERalpha/ERbeta expression levels in these cells or tissues and the potential of the estrogen agonists to activate ERalpha and/or ERbeta.

  15. Imaging regional variation of cellular proliferation in gliomas using 3'-deoxy-3'-[18F]fluorothymidine positron-emission tomography: an image-guided biopsy study

    International Nuclear Information System (INIS)

    Price, S.J.; Fryer, T.D.; Cleij, M.C.; Dean, A.F.; Joseph, J.; Salvador, R.; Wang, D.D.; Hutchinson, P.J.; Clark, J.C.; Burnet, N.G.; Pickard, J.D.; Aigbirhio, F.I.

    2009-01-01

    Aim: To compare regional variations in uptake of 3'-deoxy-3'- [ 18 F]-fluorothymidine (FLT) images using positron-emission tomography (PET) with measures of cellular proliferation from biopsy specimens obtained by image-guided brain biopsies. Materials and methods: Fourteen patients with a supratentorial glioma that required an image-guided brain biopsy were imaged preoperatively with dynamic PET after the administration of FLT. Maps of FLT irreversible uptake rate (K i ) and standardized uptake value (SUV) were calculated. These maps were co-registered to a gadolinium-enhanced T1-weighted spoiled gradient echo (SPGR) sequence that was used for biopsy guidance, and the mean and maximum K i and SUV determined for each biopsy site. These values were correlated with the MIB-1 labelling index (a tissue marker of proliferation) from these biopsy sites. Results: A total of 57 biopsy sites were studied. Although all measures correlated with MIB-1 labelling index, K i max provided the best correlation (Pearson coefficient, r = 0.68; p i mean (±SD) was significantly higher than in normal tissue (3.3 ± 1.7 x 10 -3 ml plasma /min/ml tissue versus 1.2 ± 0.7 x 10 -3 ml plasma /min/ml tissue ; p = 0.001). High-grade gliomas showed heterogeneous uptake with a mean K i of 7.7 ± 4 x 10 -3 ml plasma /min/ml tissue . A threshold K i mean of 1.8 x 10 -3 differentiates between normal tissue and tumour (sensitivity 84%, specificity 88%); however, the latter threshold underestimated the extent of tumour in half the cases. SUV closely agreed with K i measurements. Conclusion: FLT PET is a useful marker of cellular proliferation that correlates with regional variation in cellular proliferation; however, it is unable to identify the margin of gliomas

  16. Andrographolide Suppresses MV4-11 Cell Proliferation through the Inhibition of FLT3 Signaling, Fatty Acid Synthesis and Cellular Iron Uptake

    Directory of Open Access Journals (Sweden)

    Xiao Chen

    2017-08-01

    Full Text Available Background: Andrographolide (ADR, the main active component of Andrographis paniculata, displays anticancer activity in various cancer cell lines, among which leukemia cell lines exhibit the highest sensitivity to ADR. In particular, ADR was also reported to have reduced drug resistance in multidrug resistant cell lines. However, the mechanism of action (MOA of ADR’s anticancer and anti-drug-resistance activities remain elusive. Methods: In this study, we used the MV4-11 cell line, a FLT3 positive acute myeloid leukemia (AML cell line that displays multidrug resistance, as our experimental system. We first evaluated the effect of ADR on MV4-11 cell proliferation. Then, a quantitative proteomics approach was applied to identify differentially expressed proteins in ADR-treated MV4-11 cells. Finally, cellular processes and signal pathways affected by ADR in MV4-11 cell were predicted with proteomic analysis and validated with in vitro assays. Results: ADR inhibits MV4-11 cell proliferation in a dose- and time-dependent manner. With a proteomic approach, we discovered that ADR inhibited fatty acid synthesis, cellular iron uptake and FLT3 signaling pathway in MV4-11 cells. Conclusions: ADR inhibits MV4-11 cell proliferation through inhibition of fatty acid synthesis, iron uptake and protein synthesis. Furthermore, ADR reduces drug resistance by blocking FLT3 signaling.

  17. Control of cellular proliferation by modulation of oxidative phosphorylation in human and rodent fast-growing tumor cells

    International Nuclear Information System (INIS)

    Rodriguez-Enriquez, Sara; Vital-Gonzalez, Paola A.; Flores-Rodriguez, Fanny L.; Marin-Hernandez, Alvaro; Ruiz-Azuara, Lena; Moreno-Sanchez, Rafael

    2006-01-01

    The relationship between cell proliferation and the rates of glycolysis and oxidative phosphorylation in HeLa (human) and AS-30D (rodent) tumor cells was evaluated. In glutamine plus glucose medium, both tumor lines grew optimally. Mitochondria were the predominant source of ATP in both cell types (66-75%), despite an active glycolysis. In glucose-free medium with glutamine, proliferation of both lines diminished by 30% but oxidative phosphorylation and the cytosolic ATP level increased by 50%. In glutamine-free medium with glucose, proliferation, oxidative phosphorylation and ATP concentration diminished drastically, although the cells were viable. Oligomycin, in medium with glutamine plus glucose, abolished growth of both tumor lines, indicating an essential role of mitochondrial ATP for tumor progression. The presumed mitochondrial inhibitors rhodamines 123 and 6G, and casiopeina II-gly, inhibited tumor cell proliferation and oxidative phosphorylation, but also glycolysis. In contrast, gossypol, iodoacetate and arsenite strongly blocked glycolysis; however, they did not affect tumor proliferation or mitochondrial metabolism. Growth of both tumor lines was highly sensitive to rhodamines and casiopeina II-gly, with IC 5 values for HeLa cells lower than 0.5 μM, whereas viability and proliferation of human lymphocytes were not affected by these drugs (IC 5 > 30 μM). Moreover, rhodamine 6G and casiopeina II-gly, at micromolar doses, prolonged the survival of animals bearing i.p. implanted AS-30D hepatoma. It is concluded that fast-growing tumor cells have a predominantly oxidative type of metabolism, which might be a potential therapeutic target

  18. Identification of irradiated food. III. Identification of irradiated potato tubers by means of a test based on the cellular proliferation

    International Nuclear Information System (INIS)

    Fernandez Gonzalez, J.; Mazon Matanzo, M.P.

    1976-01-01

    The effect of gamma radiation on the formation of the wound periderm in potato tubers cut in halves and on the proliferation of the potato parenchyma cultivated ''in vitro'' is studied. Doses of 3 Krad and higher ones completely inhibit the formation of the wound periderm and the growth of protuberances in the fragments of the parenchyma cultivated ''in vitro''. In the control and IPC treated tubers the proliferation was normal and abundant, in the tubers as well as in the potato parenchyma tissues cultivated ''in vitro''.(author) [es

  19. Mapping cellular processes in the mesenchyme during palatal development in the absence of Tbx1 reveals complex proliferation changes and perturbed cell packing and polarity.

    Science.gov (United States)

    Brock, Lara J; Economou, Andrew D; Cobourne, Martyn T; Green, Jeremy B A

    2016-03-01

    The 22q11 deletion syndromes represent a spectrum of overlapping conditions including cardiac defects and craniofacial malformations. Amongst the craniofacial anomalies that are seen, cleft of the secondary palate is a common feature. Haploinsufficiency of TBX1 is believed to be a major contributor toward many of the developmental structural anomalies that occur in these syndromes, and targeted deletion of Tbx1 in the mouse reproduces many of these malformations, including cleft palate. However, the cellular basis of this defect is only poorly understood. Here, palatal development in the absence of Tbx1 has been analysed, focusing on cellular properties within the whole mesenchymal volume of the palatal shelves. Novel image analyses and data presentation tools were applied to quantify cell proliferation rates, including regions of elevated as well as reduced proliferation, and cell packing in the mesenchyme. Also, cell orientations (nucleus-Golgi axis) were mapped as a potential marker of directional cell movement. Proliferation differed only subtly between wild-type and mutant until embryonic day (E)15.5 when proliferation in the mutant was significantly lower. Tbx1(-/-) palatal shelves had slightly different cell packing than wild-type, somewhat lower before elevation and higher at E15.5 when the wild-type palate has elevated and fused. Cell orientation is biased towards the shelf distal edge in the mid-palate of wild-type embryos but is essentially random in the Tbx1(-/-) mutant shelves, suggesting that polarised processes such as directed cell rearrangement might be causal for the cleft phenotype. The implications of these findings in the context of further understanding Tbx1 function during palatogenesis and of these methods for the more general analysis of genotype-phenotype functional relationships are discussed. © 2015 The Authors. Journal of Anatomy published by John Wiley & Sons Ltd on behalf of Anatomical Society.

  20. Pivotal Roles of Peroxisome Proliferator-Activated Receptors (PPARs) and Their Signal Cascade for Cellular and Whole-Body Energy Homeostasis.

    Science.gov (United States)

    Lamichane, Shreekrishna; Dahal Lamichane, Babita; Kwon, Sang-Mo

    2018-03-22

    Peroxisome proliferator-activated receptors (PPARs), members of the nuclear receptor superfamily, are important in whole-body energy metabolism. PPARs are classified into three isoforms, namely, PPARα, β/δ, and γ. They are collectively involved in fatty acid oxidation, as well as glucose and lipid metabolism throughout the body. Importantly, the three isoforms of PPARs have complementary and distinct metabolic activities for energy balance at a cellular and whole-body level. PPARs also act with other co-regulators to maintain energy homeostasis. When endogenous ligands bind with these receptors, they regulate the transcription of genes involved in energy homeostasis. However, the exact molecular mechanism of PPARs in energy metabolism remains unclear. In this review, we summarize the importance of PPAR signals in multiple organs and focus on the pivotal roles of PPAR signals in cellular and whole-body energy homeostasis.

  1. Store-Operated Ca2+ Entry Does Not Control Proliferation in Primary Cultures of Human Metastatic Renal Cellular Carcinoma

    Directory of Open Access Journals (Sweden)

    Silvia Dragoni

    2014-01-01

    Full Text Available Store-operated Ca2+ entry (SOCE is activated following depletion of the inositol-1,4,5-trisphosphate (InsP3-sensitive Ca2+ pool to regulate proliferation in immortalized cell lines established from either primary or metastatic lesions. The molecular nature of SOCE may involve both Stim1, which senses Ca2+ levels within the endoplasmic reticulum (ER Ca2+ reservoir, and a number of a Ca2+-permeable channels on the plasma membrane, including Orai1, Orai3, and members of the canonical transient receptor (TRPC1–7 family of ion channels. The present study was undertaken to assess whether SOCE is expressed and controls proliferation in primary cultures isolated from secondary lesions of heavily pretreated metastatic renal cell carcinoma (mRCC patients. SOCE was induced following pharmacological depletion of the ER Ca2+ store, but not by InsP3-dependent Ca2+ release. Metastatic RCC cells express Stim1-2, Orai1–3, and TRPC1–7 transcripts and proteins. In these cells, SOCE was insensitive to BTP-2, 10 µM Gd3+ and Pyr6, while it was inhibited by 100 µM Gd3+, 2-APB, and carboxyamidotriazole (CAI. Neither Gd3+ nor 2-APB or CAI impaired mRCC cell proliferation. Consistently, no detectable Ca2+ signal was elicited by growth factor stimulation. Therefore, a functional SOCE is expressed but does not control proliferation of mRCC cells isolated from patients resistant to multikinase inhibitors.

  2. A rapid fluorometric method for semiautomated determination of cytotoxicity and cellular proliferation of human tumor cell lines in microculture.

    Science.gov (United States)

    Larsson, R; Nygren, P

    1989-01-01

    A fluorometric method for the determination of cellular growth and cytotoxicity of human tumor cell lines in 96-well microculture plates is described. The assay is based on the combined use of the DNA-binding dye Hoechst 33342 and the fluorogenic substrate fluorescein diacetate (FDA). Hoechst 33342 undergoes a dramatic enhancement of fluorescence when specifically intercalated with cellular DNA, whereas the FDA fluorescence is dependent on cellular hydrolysis of the non-fluorescent substrate into its fluorescent product. Fluorescence from both dyes was linearly related to the density of freshly seeded cells (6 x 10(3)-1 x 10(5)/well) and correlated well with physical cell count of cells under normal culture conditions as well as in response to the vinca alkaloid vincristine. However, the amount of FDA fluorescence produces and retained by the cultures was clearly dependent on the fraction of intact and viable cells, whereas the fluorescence reported by Hoechst 33342 was not. The assay was found to be simple, reliable and many samples could be analysed in a short period of time with minimal waste of cells and biological reagents. Apart from giving an estimate of cell density, the protocol described also provides a separate index of viability which in certain situations may be of importance for distinguishing between cytocidal and cytostatic drug actions. The method may be well suited for several applications, including the large scale screening for antitumor activity of compounds with potential cytocidal or cytostatic actions.

  3. Engagement of cellular prion protein with the co-chaperone Hsp70/90 organizing protein regulates the proliferation of glioblastoma stem-like cells.

    Science.gov (United States)

    Iglesia, Rebeca Piatniczka; Prado, Mariana Brandão; Cruz, Lilian; Martins, Vilma Regina; Santos, Tiago Góss; Lopes, Marilene Hohmuth

    2017-04-17

    Glioblastoma (GBM), a highly aggressive brain tumor, contains a subpopulation of glioblastoma stem-like cells (GSCs) that play roles in tumor maintenance, invasion, and therapeutic resistance. GSCs are therefore a promising target for GBM treatment. Our group identified the cellular prion protein (PrP C ) and its partner, the co-chaperone Hsp70/90 organizing protein (HOP), as potential target candidates due to their role in GBM tumorigenesis and in neural stem cell maintenance. GSCs expressing different levels of PrP C were cultured as neurospheres with growth factors, and characterized with stem cells markers and adhesion molecules markers through immunofluorescence and flow cytometry. We than evaluated GSC self-renewal and proliferation by clonal density assays and BrdU incorporation, respectively, in front of recombinant HOP treatment, combined or not with a HOP peptide which mimics the PrP C binding site. Stable silencing of HOP was also performed in parental and/or PrP C -depleted cell populations, and proliferation in vitro and tumor growth in vivo were evaluated. Migration assays were performed on laminin-1 pre-coated glass. We observed that, when GBM cells are cultured as neurospheres, they express specific stemness markers such as CD133, CD15, Oct4, and SOX2; PrP C is upregulated compared to monolayer culture and co-localizes with CD133. PrP C silencing downregulates the expression of molecules associated with cancer stem cells, upregulates markers of cell differentiation and affects GSC self-renewal, pointing to a pivotal role for PrP C in the maintenance of GSCs. Exogenous HOP treatment increases proliferation and self-renewal of GSCs in a PrP C -dependent manner while HOP knockdown disturbs the proliferation process. In vivo, PrP C and/or HOP knockdown potently inhibits the growth of subcutaneously implanted glioblastoma cells. In addition, disruption of the PrP C -HOP complex by a HOP peptide, which mimics the PrP C binding site, affects GSC self

  4. Fatty acid synthase as a factor required for exercise-induced cognitive enhancement and dentate gyrus cellular proliferation.

    Directory of Open Access Journals (Sweden)

    Nataliya E Chorna

    Full Text Available Voluntary running is a robust inducer of adult hippocampal neurogenesis. Given that fatty acid synthase (FASN, the key enzyme for de novo fatty acid biosynthesis, is critically involved in proliferation of embryonic and adult neural stem cells, we hypothesized that FASN could mediate both exercise-induced cell proliferation in the subgranular zone (SGZ of the dentate gyrus (DG and enhancement of spatial learning and memory. In 20 week-old male mice, voluntary running-induced hippocampal-specific upregulation of FASN was accompanied also by hippocampal-specific accumulation of palmitate and stearate saturated fatty acids. In experiments addressing the functional role of FASN in our experimental model, chronic intracerebroventricular (i.c.v. microinfusions of C75, an irreversible FASN inhibitor, and significantly impaired exercise-mediated improvements in spatial learning and memory in the Barnes maze. Unlike the vehicle-injected mice, the C75 group adopted a non-spatial serial escape strategy and displayed delayed escape latencies during acquisition and memory tests. Furthermore, pharmacologic blockade of FASN function with C75 resulted in a significant reduction, compared to vehicle treated controls, of the number of proliferative cells in the DG of running mice as measured by immunoreactive to Ki-67 in the SGZ. Taken together, our data suggest that FASN plays an important role in exercise-mediated cognitive enhancement, which might be associated to its role in modulating exercise-induced stimulation of neurogenesis.

  5. Fatty acid synthase as a factor required for exercise-induced cognitive enhancement and dentate gyrus cellular proliferation.

    Science.gov (United States)

    Chorna, Nataliya E; Santos-Soto, Iván J; Carballeira, Nestor M; Morales, Joan L; de la Nuez, Janneliz; Cátala-Valentin, Alma; Chornyy, Anatoliy P; Vázquez-Montes, Adrinel; De Ortiz, Sandra Peña

    2013-01-01

    Voluntary running is a robust inducer of adult hippocampal neurogenesis. Given that fatty acid synthase (FASN), the key enzyme for de novo fatty acid biosynthesis, is critically involved in proliferation of embryonic and adult neural stem cells, we hypothesized that FASN could mediate both exercise-induced cell proliferation in the subgranular zone (SGZ) of the dentate gyrus (DG) and enhancement of spatial learning and memory. In 20 week-old male mice, voluntary running-induced hippocampal-specific upregulation of FASN was accompanied also by hippocampal-specific accumulation of palmitate and stearate saturated fatty acids. In experiments addressing the functional role of FASN in our experimental model, chronic intracerebroventricular (i.c.v.) microinfusions of C75, an irreversible FASN inhibitor, and significantly impaired exercise-mediated improvements in spatial learning and memory in the Barnes maze. Unlike the vehicle-injected mice, the C75 group adopted a non-spatial serial escape strategy and displayed delayed escape latencies during acquisition and memory tests. Furthermore, pharmacologic blockade of FASN function with C75 resulted in a significant reduction, compared to vehicle treated controls, of the number of proliferative cells in the DG of running mice as measured by immunoreactive to Ki-67 in the SGZ. Taken together, our data suggest that FASN plays an important role in exercise-mediated cognitive enhancement, which might be associated to its role in modulating exercise-induced stimulation of neurogenesis.

  6. Expression of p21/waf1 in oral squamous cell carcinomas--correlation with p53 and mdm2 and cellular proliferation index.

    Science.gov (United States)

    Ng, I O; Lam, K Y; Ng, M; Regezi, J A

    1999-01-01

    The cyclin-dependent kinase inhibitor p21/waf1 is regulated by p53-dependent and p53-independent pathways. In addition, mdm2 is an oncogene which forms an auto-regulatory loop with the normal p53 protein and its role has been implicated in oncogenesis. To determine whether a correlation exists between the expression of these gene products, tumor differentiation, tumor staging and radiation therapy, we investigated the expression of p21, p53 and mdm2, and cellular proliferation by Ki-67 (MIB1) labeling index using immunohistochemistry in 88 human oral squamous cell carcinoma (SCC) samples from 56 patients. Tumor expression of all nuclear proteins was scored according to the percentage of positive cancer nuclei, both with the cancer tissue as a whole as well as in different epithelial compartments of differentiation. Positive p21, p53, mdm2 and MIB1 staining was present in 82.4, 67.8, 25.9 and 98.8% of the SCC samples. The staining in different epithelial compartments of differentiation varied: those of p21 and mdm2 present predominantly in suprabasal and upper regions of the tumors: those of p53 and MIB1 in basal and suprabasal regions. Higher levels of p21 expression were seen in actively proliferating tumors (P = 0.025). p21 expression positively correlated with mdm2 expression but not with p53 expression. Moreover, the level of p21 expression was higher in older patients (P = 0.024) and female patients (P = 0.008). There was no significant association among p53, mdm2 and MIB1. Expression of p53 was higher in tumors with poorer cellular differentiation and in younger patients (P = 0.038 and 0.028). There was no association between tumor stage by TNM classification and the expression of any of these gene products or proliferation index. Radiation therapy did not alter the expression of any of these. To conclude, p21 protein was overexpressed in oral SCCs, and this overexpression was related to cell proliferation index and mdm2 expression but independent of p53

  7. Sensitivity to methylmercury toxicity is enhanced in oxoguanine glycosylase 1 knockout murine embryonic fibroblasts and is dependent on cellular proliferation capacity

    Energy Technology Data Exchange (ETDEWEB)

    Ondovcik, Stephanie L. [Department of Pharmaceutical Sciences, University of Toronto, Toronto, Ontario M5S 3M2 (Canada); Tamblyn, Laura; McPherson, John Peter [Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario M5S 1A8 (Canada); Wells, Peter G., E-mail: pg.wells@utoronto.ca [Department of Pharmaceutical Sciences, University of Toronto, Toronto, Ontario M5S 3M2 (Canada); Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario M5S 1A8 (Canada)

    2013-07-01

    Methylmercury (MeHg) is a persistent environmental contaminant with potent neurotoxic action for which the underlying molecular mechanisms remain to be conclusively delineated. Our objectives herein were twofold: first, to corroborate our previous findings of an increased sensitivity of spontaneously-immortalized oxoguanine glycosylase 1-null (Ogg1{sup −/−}) murine embryonic fibroblasts (MEFs) to MeHg through generation of Simian virus 40 (SV40) large T antigen-immortalized wild-type and Ogg1{sup −/−} MEFs; and second, to determine whether MeHg toxicity is proliferation-dependent. As with the spontaneously-immortalized cells used previously, the SV40 large T antigen-immortalized cells exhibited similar tendencies to undergo MeHg-initiated cell cycle arrest, with increased sensitivity in the Ogg1{sup −/−} MEFs as measured by clonogenic survival and DNA damage. Compared to exponentially growing cells, those seeded at a higher density exhibited compromised proliferation, which proved protective against MeHg-mediated cell cycle arrest and induction of DNA double strand breaks (DSBs), measured by phosphorylation of the core histone H2A variant (H2AX) on serine 139 (γH2AX), and by its functional confirmation by micronucleus assessment. This enhanced sensitivity of Ogg1{sup −/−} MEFs to MeHg toxicity using discrete SV40 immortalization corroborates our previous studies, and suggests a novel role for OGG1 in minimizing MeHg-initiated DNA lesions that trigger replication-associated DSBs. Furthermore, proliferative capacity may determine MeHg toxicity in vivo and in utero. Accordingly, variations in cellular proliferative capacity and interindividual variability in repair activity may modulate the risk of toxicological consequences following MeHg exposure. - Highlights: • SV40 large T antigen-immortalized Ogg1{sup −/−} cells are more sensitive to MeHg. • Sensitivity to MeHg is dependent on cellular proliferation capacity. • OGG1 maintains genomic

  8. Expression of R132H mutational IDH1 in human U87 glioblastoma cells affects the SREBP1a pathway and induces cellular proliferation.

    Science.gov (United States)

    Zhu, Jian; Cui, Gang; Chen, Ming; Xu, Qinian; Wang, Xiuyun; Zhou, Dai; Lv, Shengxiang; Fu, Linshan; Wang, Zhong; Zuo, Jianling

    2013-05-01

    Sterol regulatory element-binding protein-1a (SREBP1a) is a member of the SREBP family of transcription factors, which mainly controls homeostasis of lipids. SREBP1a can also activate the transcription of isocitrate dehydrogenase 1 (IDH1) by binding to its promoter region. IDH1 mutations, especially R132H mutation of IDH1, are a common feature of a major subset of human gliomas. There are few data available on the relationship between mutational IDH1 expression and SREBP1a pathway. In this study, we investigated cellular effects and SREBP1a pathway alterations caused by R132H mutational IDH1 expression in U87 cells. Two glioma cell lines, stably expressing mutational (U87/R132H) or wild type (U87/wt) IDH1, were established. A cell line, stably transfected with pcDNA3.1(+) (U87/vector), was generated as a control. Click-iT EdU assay, sulforhodamine B assay, and wound healing assay respectively showed that the expression of R132H induced cellular proliferation, cell growth, and cell migration. Western blot revealed that SREBP1 was increased in U87/R132H compared with that in U87/wt. Elevated SREBP1a and several its target genes, but not SREBP1c, were detected by real-time polymerase chain reaction in U87/R132H. All these findings indicated that R132H mutational IDH1 is involved in the regulation of proliferation, growth, and migration of glioma cells. These effects may partially be mediated by SREBP1a pathway.

  9. Gene Expression of Glucose Transporter 1 (GLUT1), Hexokinase 1 and Hexokinase 2 in Gastroenteropancreatic Neuroendocrine Tumors: Correlation with F-18-fluorodeoxyglucose Positron Emission Tomography and Cellular Proliferation.

    Science.gov (United States)

    Binderup, Tina; Knigge, Ulrich Peter; Federspiel, Birgitte; Sommer, Peter; Hasselby, Jane Preuss; Loft, Annika; Kjaer, Andreas

    2013-10-29

    Neoplastic tissue exhibits high glucose utilization and over-expression of glucose transporters (GLUTs) and hexokinases (HKs), which can be imaged by (18)F-Fluorodeoxyglucose-positron emission tomography (FDG-PET). The aim of the present study was to investigate the expression of glycolysis-associated genes and to compare this with FDG-PET imaging as well as with the cellular proliferation index in two cancer entities with different malignant potential. Using real-time PCR, gene expression of GLUT1, HK1 and HK2 were studied in 34 neuroendocrine tumors (NETs) in comparison with 14 colorectal adenocarcinomas (CRAs). The Ki67 proliferation index and, when available, FDG-PET imaging was compared with gene expression. Overexpression of GLUT1 gene expression was less frequent in NETs (38%) compared to CRAs (86%), P = 0.004. HK1 was overexpressed in 41% and 71% of NETs and CRAs, respectively (P = 0.111) and HK2 was overexpressed in 50% and 64% of NETs and CRAs, respectively (P = 0.53). There was a significant correlation between the Ki67 proliferation index and GLUT1 gene expression for the NETs (R = 0.34, P = 0.047), but no correlation with the hexokinases. FDG-PET identified foci in significantly fewer NETs (36%) than CRAs (86%), (P = 0.04). The gene expression results, with less frequent GLUT1 and HK1 upregulation in NETs, confirmed the lower metabolic activity of NETs compared to the more aggressive CRAs. In accordance with this, fewer NETs were FDG-PET positive compared to CRA tumors and FDG uptake correlated with GLUT1 gene expression.

  10. Gene Expression of Glucose Transporter 1 (GLUT1, Hexokinase 1 and Hexokinase 2 in Gastroenteropancreatic Neuroendocrine Tumors: Correlation with F-18-fluorodeoxyglucose Positron Emission Tomography and Cellular Proliferation

    Directory of Open Access Journals (Sweden)

    Andreas Kjaer

    2013-10-01

    Full Text Available Neoplastic tissue exhibits high glucose utilization and over-expression of glucose transporters (GLUTs and hexokinases (HKs, which can be imaged by 18F-Fluorodeoxyglucose-positron emission tomography (FDG-PET. The aim of the present study was to investigate the expression of glycolysis-associated genes and to compare this with FDG-PET imaging as well as with the cellular proliferation index in two cancer entities with different malignant potential. Using real-time PCR, gene expression of GLUT1, HK1 and HK2 were studied in 34 neuroendocrine tumors (NETs in comparison with 14 colorectal adenocarcinomas (CRAs. The Ki67 proliferation index and, when available, FDG-PET imaging was compared with gene expression. Overexpression of GLUT1 gene expression was less frequent in NETs (38% compared to CRAs (86%, P = 0.004. HK1 was overexpressed in 41% and 71% of NETs and CRAs, respectively (P = 0.111 and HK2 was overexpressed in 50% and 64% of NETs and CRAs, respectively (P = 0.53. There was a significant correlation between the Ki67 proliferation index and GLUT1 gene expression for the NETs (R = 0.34, P = 0.047, but no correlation with the hexokinases. FDG-PET identified foci in significantly fewer NETs (36% than CRAs (86%, (P = 0.04. The gene expression results, with less frequent GLUT1 and HK1 upregulation in NETs, confirmed the lower metabolic activity of NETs compared to the more aggressive CRAs. In accordance with this, fewer NETs were FDG-PET positive compared to CRA tumors and FDG uptake correlated with GLUT1 gene expression.

  11. CD1d-dependent expansion of NKT follicular helper cells in vivo and in vitro is a product of cellular proliferation and differentiation.

    Science.gov (United States)

    Rampuria, Pragya; Lang, Mark L

    2015-05-01

    NKT follicular helper cells (NKTfh cells) are a recently discovered functional subset of CD1d-restricted NKT cells. Given the potential for NKTfh cells to promote specific antibody responses and germinal center reactions, there is much interest in determining the conditions under which NKTfh cells proliferate and/or differentiate in vivo and in vitro. We confirm that NKTfh cells expressing the canonical semi-invariant Vα14 TCR were CXCR5(+)/ICOS(+)/PD-1(+)/Bcl6(+) and increased in number following administration of the CD1d-binding glycolipid α-galactosylceramide (α-GC) to C57Bl/6 mice. We show that the α-GC-stimulated increase in NKTfh cells was CD1d-dependent since the effect was diminished by reduced CD1d expression. In vivo and in vitro treatment with α-GC, singly or in combination with IL-2, showed that NKTfh cells increased in number to a greater extent than total NKT cells, but proliferation was near-identical in both populations. Acquisition of the NKTfh phenotype from an adoptively transferred PD-1-depleted cell population was also evident, showing that peripheral NKT cells differentiated into NKTfh cells. Therefore, the α-GC-stimulated, CD1d-dependent increase in peripheral NKTfh cells is a result of cellular proliferation and differentiation. These findings advance our understanding of the immune response following immunization with CD1d-binding glycolipids. © The Japanese Society for Immunology. 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  12. Synthesis of 2'-fluoro-5-[11C]-methyl-1-β-d-arabinofuranosyluracil ([11C]-FMAU): A potential nucleoside analog for in vivo study of cellular proliferation with PET

    International Nuclear Information System (INIS)

    Conti, Peter S.; Alauddin, Mian M.; Fissekis, John R.; Schmall, Bernard; Watanabe, Kyochi A.

    1995-01-01

    Rapid in vivo catabolism limits the use of currently available radiotracers used in tumor proliferation studies with PET. This is manifested by the need to develop complex mathematical models to interpret kinetic and metabolite data obtained from imaging studies with agents such as carbon-11 labeled thymidine. A potential carbon-11 labeled radiotracer for cellular proliferation, 2'-fluoro-5-([ 11 C]-methyl)-1-β-d-arabinofuranosyluracil (FMAU), has been prepared using a previously described method for preparation of [ 11 C]methyl-thymidine where selective alkylation of a pyrimidyl dianion is accomplished with [ 11 C]methyl iodide at the 5-position of the pyrimidine ring. FMAU shares many in vivo characteristics of thymidine, including cellular transport, phosphorylation by mammalian kinase, and incorporation into DNA. Most importantly, in vivo catabolism of FMAU is limited, potentially yielding simplified kinetic models for determination of cellular proliferation with positron emission tomography

  13. Accumulated SET protein up-regulates and interacts with hnRNPK, increasing its binding to nucleic acids, the Bcl-xS repression, and cellular proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Luciana O.; Garcia, Cristiana B.; Matos-Silva, Flavia A. [Department of Clinical Analyses, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP (Brazil); Curti, Carlos [Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP (Brazil); Leopoldino, Andréia M., E-mail: andreiaml@usp.br [Department of Clinical Analyses, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP (Brazil)

    2014-02-28

    Highlights: • hnRNPK is a new target of SET. • SET regulates hnRNPK. • SET and hnRNPK accumulation promotes tumorigenesis. • SET accumulation is a potential model to study genes regulated by SET-hnRNPK. - Abstract: SET and hnRNPK are proteins involved in gene expression and regulation of cellular signaling. We previously demonstrated that SET accumulates in head and neck squamous cell carcinoma (HNSCC); hnRNPK is a prognostic marker in cancer. Here, we postulate that SET and hnRNPK proteins interact to promote tumorigenesis. We performed studies in HEK293 and HNSCC (HN6, HN12, and HN13) cell lines with SET/hnRNPK overexpression and knockdown, respectively. We found that SET and/or hnRNPK protein accumulation increased cellular proliferation. SET accumulation up-regulated hnRNPK mRNA and total/phosphorylated protein, promoted hnRNPK nuclear location, and reduced Bcl-x mRNA levels. SET protein directly interacted with hnRNPK, increasing both its binding to nucleic acids and Bcl-xS repression. We propose that hnRNPK should be a new target of SET and that SET–hnRNPK interaction, in turn, has potential implications in cell survival and malignant transformation.

  14. Ultrastructural Analysis of Myoblast Fusion in Drosophila

    OpenAIRE

    Zhang, Shiliang; Chen, Elizabeth H.

    2008-01-01

    Myoblast fusion in Drosophila has become a powerful genetic system with which to unravel the mechanisms underlying cell fusion. The identification of important components of myoblast fusion by genetic analysis has led to a molecular pathway toward our understanding of this cellular process. In addition to the application of immunohistochemistry and live imaging techniques to visualize myoblast fusion at the light microscopic level, ultrastructural analysis using electron microscopy remains an...

  15. The MRC-5 human embryonal lung fibroblast two-dimensional gel cellular protein database: quantitative identification of polypeptides whose relative abundance differs between quiescent, proliferating and SV40 transformed cells

    DEFF Research Database (Denmark)

    Celis, J E; Dejgaard, K; Madsen, Peder

    1990-01-01

    A new version of the MRC-5 two-dimensional gel cellular protein database (Celis et al., Electrophoresis 1989, 10, 76-115) is presented. Gels were scanned with a Molecular Dynamics laser scanner and processed by the PDQUEST II software. A total of 1895 [35S]methionine-labeled cellular polypeptides...... (1323 with isoelectric focusing and 572 with nonequilibrium pH gradient electrophoresis) are recorded in this database, containing quantitative and qualitative data on the relative abundance of cellular proteins synthesized by quiescent, proliferating and SV40 transformed MRC-5 fibroblasts. Of the 592...... proteins quantitated so far, the levels of 138 were up- or down-regulated (51 and 87, respectively) by two times or more in the transformed cells as compared to their normal proliferating counterparts, while only 14 behaved similarly in quiescent cells. Seven MRC-5 SV40 proteins, including plastin and two...

  16. Cellular prion protein and γ-synuclein overexpression in LS 174T colorectal cancer cell drives endothelial proliferation-to-differentiation switch.

    Science.gov (United States)

    Ong, Sing-Hui; Goh, Kai-Wey; Chieng, Cornelius Kwang-Lee; Say, Yee-How

    2018-01-01

    Tumor-induced angiogenesis is an imperative event in pledging new vasculature for tumor metastasis. Since overexpression of neuronal proteins gamma-synuclein (γ-Syn) and cellular prion protein (PrP C ) is always detected in advanced stages of cancer diseases which involve metastasis, this study aimed to investigate whether γ-Syn or PrP C overexpression in colorectal adenocarcinoma, LS 174T cells affects angiogenesis of endothelial cells, EA.hy 926 (EA). EA cells were treated with conditioned media (CM) of LS 174T-γ-Syn or LS 174T-PrP, and their proliferation, invasion, migration, adhesion and ability to form angiogenic tubes were assessed using a range of biological assays. To investigate plausible background mechanisms in conferring the properties of EA cells above, nitrite oxide (NO) levels were measured and the expression of angiogenesis-related factors was assessed using a human angiogenesis antibody array. EA proliferation was significantly inhibited by LS 174T-PrP CM whereas its telomerase activity was reduced by CM of LS 174T-γ-Syn or LS 174T-PrP, as compared to EA incubated with LS 174T CM. Besides, LS 174T-γ-Syn CM or LS 174T-PrP CM inhibited EA invasion and migration in Boyden chamber assay. Furthermore, LS 174T-γ-Syn CM significantly inhibited EA migration in scratch wound assay. Gelatin zymography revealed reduced secretion of MMP-2 and MMP-9 by EA treated with LS 174T-γ-Syn CM or LS 174T-PrP CM. In addition, cell adhesion assay showed lesser LS 174T-γ-Syn or LS 174T-PrP cells adhered onto EA, as compared to LS 174T. In tube formation assay, LS 174T-γ-Syn CM or LS 174T-PrP CM induced EA tube formation. Increased NO secretion by EA treated with LS 174T-γ-Syn CM or LS 174T-PrP CM was also detected. Lastly, decreased expression of pro-angiogenic factors like CXCL16, IGFBP-2 and amphiregulin in LS 174T-γ-Syn CM or LS 174T-PrP CM was detected using the angiogenesis antibody array. These results suggest that overexpression of γ-Syn or PrP C could

  17. III. Cellular ultrastructures in situ as key to understanding tumor energy metabolism: biological significance of the Warburg effect [v1; ref status: indexed, http://f1000r.es/a0

    Directory of Open Access Journals (Sweden)

    Halina Witkiewicz

    2013-01-01

    Full Text Available 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

  18. Lamellar Hole-Associated Epiretinal Proliferation in Comparison to Epiretinal Membranes of Macular Pseudoholes.

    Science.gov (United States)

    Compera, Denise; Entchev, Enrico; Haritoglou, Christos; Scheler, Renate; Mayer, Wolfgang J; Wolf, Armin; Kampik, Anselm; Schumann, Ricarda G

    2015-08-01

    To compare immunocytochemical and ultrastructural characteristics of "lamellar hole-associated epiretinal proliferation" in lamellar macular holes with "conventional epiretinal membrane" in macular pseudoholes. A consecutive observational case series, laboratory investigation. We analyzed surgically excised flat-mounted internal limiting membrane specimens and epiretinal membrane specimens removed from 25 eyes of 25 patients with lamellar macular holes (11 eyes) and macular pseudoholes (14 eyes) using interference and phase-contrast microscopy, immunocytochemistry, and transmission electron microscopy. By spectral-domain optical coherence tomography, epiretinal material of homogenous reflectivity without contractive properties was categorized as lamellar hole-associated epiretinal proliferation, whereas tractional epiretinal membranes presenting contractive properties were termed conventional epiretinal membrane. Lamellar hole-associated epiretinal proliferation was seen in 73% of eyes with lamellar macular hole. Eyes with macular pseudohole presented with conventional epiretinal membrane. In lamellar hole-associated epiretinal proliferation, positive immunoreactivity for anti-glial fibrillary acidic protein, hyalocyte markers, and anti-collagen type I and III was seen. In contrast, specimens of macular pseudoholes were positive for α-smooth muscle actin and anti-glial fibrillary acidic protein, predominantly. Cellular ultrastructure showed that lamellar hole-associated epiretinal proliferation of lamellar macular holes mainly consisted of fibroblasts and hyalocytes, whereas myofibroblasts dominated in conventional epiretinal membranes of macular pseudoholes. Cells within lamellar hole-associated epiretinal proliferation appear to originate from vitreous and possess less contractive properties than cells of conventional epiretinal membranes. Our findings point to differences in pathogenesis in a subgroup of lamellar macular holes presenting lamellar hole

  19. Increased cellular immune responses and CD4+ T-cell proliferation correlate with reduced plasma viral load in SIV challenged recombinant simian varicella virus - simian immunodeficiency virus (rSVV-SIV vaccinated rhesus macaques

    Directory of Open Access Journals (Sweden)

    Pahar Bapi

    2012-08-01

    Full Text Available Abstract Background An effective AIDS vaccine remains one of the highest priorities in HIV-research. Our recent study showed that vaccination of rhesus macaques with recombinant simian varicella virus (rSVV vector – simian immunodeficiency virus (SIV envelope and gag genes, induced neutralizing antibodies and cellular immune responses to SIV and also significantly reduced plasma viral loads following intravenous pathogenic challenge with SIVMAC251/CX1. Findings The purpose of this study was to define cellular immunological correlates of protection in rSVV-SIV vaccinated and SIV challenged animals. Immunofluorescent staining and multifunctional assessment of SIV-specific T-cell responses were evaluated in both Experimental and Control vaccinated animal groups. Significant increases in the proliferating CD4+ T-cell population and polyfunctional T-cell responses were observed in all Experimental-vaccinated animals compared with the Control-vaccinated animals. Conclusions Increased CD4+ T-cell proliferation was significantly and inversely correlated with plasma viral load. Increased SIV-specific polyfunctional cytokine responses and increased proliferation of CD4+ T-cell may be crucial to control plasma viral loads in vaccinated and SIVMAC251/CX1 challenged macaques.

  20. Assessment of glucose metabolism and cellular proliferation in multiple myeloma: a first report on combined 18F-FDG and 18F-FLT PET/CT imaging.

    Science.gov (United States)

    Sachpekidis, C; Goldschmidt, H; Kopka, K; Kopp-Schneider, A; Dimitrakopoulou-Strauss, A

    2018-04-10

    Despite the significant upgrading in recent years of the role of 18 F-FDG PET/CT in multiple myeloma (MM) diagnostics, there is a still unmet need for myeloma-specific radiotracers. 3'-Deoxy-3'-[ 18 F]fluorothymidine ( 18 F-FLT) is the most studied cellular proliferation PET agent, considered a potentially new myeloma functional imaging tracer. The aim of this pilot study was to evaluate 18 F-FLT PET/CT in imaging of MM patients, in the context of its combined use with 18 F-FDG PET/CT. Eight patients, four suffering from symptomatic MM and four suffering from smoldering MM (SMM), were enrolled in the study. All patients underwent 18 F-FDG PET/CT and 18 F-FLT PET/CT imaging by means of static (whole body) and dynamic PET/CT of the lower abdomen and pelvis (dPET/CT) in two consecutive days. The evaluation of PET/CT studies was based on qualitative evaluation, semi-quantitative (SUV) calculation, and quantitative analysis based on two-tissue compartment modeling. 18 F-FDG PET/CT demonstrated focal, 18 F-FDG avid, MM-indicative bone marrow lesions in five patients. In contrary, 18 F-FLT PET/CT showed focal, 18 F-FLT avid, myeloma-indicative lesions in only two patients. In total, 48 18 F-FDG avid, focal, MM-indicative lesions were detected with 18 F-FDG PET/CT, while 17 18 F-FLT avid, focal, MM-indicative lesions were detected with 18 F-FLT PET/CT. The number of myeloma-indicative lesions was significantly higher for 18 F-FDG PET/CT than for 18 F-FLT PET/CT. A common finding was a mismatch of focally increased 18 F-FDG uptake and reduced 18 F-FLT uptake (lower than the surrounding bone marrow). Moreover, 18 F-FLT PET/CT was characterized by high background activity in the bone marrow compartment, further complicating the evaluation of bone marrow lesions. Semi-quantitative evaluation revealed that both SUV mean and SUV max were significantly higher for 18 F-FLT than for 18 F-FDG in both MM lesions and reference tissue. SUV values were higher in MM lesions than in

  1. Influence of Irradiated Peripheral Blood Mononuclear Cells on Both Ex Vivo Proliferation of Human Natural Killer Cells and Change in Cellular Property

    Directory of Open Access Journals (Sweden)

    María Delso-Vallejo

    2017-07-01

    Full Text Available Clinical studies with adoptive immunotherapy using allogeneic natural killer (NK cells showed feasibility, but also limitation regarding the transfused absolute cell numbers. First promising results with peripheral blood mononuclear cells (PBMCs as feeder cells to improve the final cell number need further optimization and investigation of the unknown controlling mechanism in the cross-talk to NK cells. We investigated the influence of irradiated autologous PBMCs to boost NK cell proliferation in the presence of OKT3 and IL-2. Our findings demonstrate a requirement for receptor–ligand interactions between feeders and NK cells to produce soluble factors that can sustain NK cell proliferation. Thus, both physical contact between feeder and NK cells, and soluble factors produced in consequence, are required to fully enhance NK cell ex vivo proliferation. This occurred with an indispensable role of the cross-talk between T cells, monocytes, and NK cells, while B cells had no further influence in supporting NK cell proliferation under these co-culture conditions. Moreover, gene expression analysis of highly proliferating and non-proliferating NK cells revealed important phenotypic changes on 5-day cultured NK cells. Actively proliferating NK cells have reduced Siglec-7 and -9 expression compared with non-proliferating and resting NK cells (day 0, independently of the presence of feeder cells. Interestingly, proliferating NK cells cultured with feeder cells contained increased frequencies of cells expressing RANKL, B7-H3, and HLA class II molecules, particularly HLA-DR, compared with resting NK cells or expanded with IL-2 only. A subset of HLA-DR expressing NK cells, co-expressing RANKL, and B7-H3 corresponded to the most proliferative population under the established co-culture conditions. Our results highlight the importance of the crosstalk between T cells, monocytes, and NK cells in autologous feeder cell-based ex vivo NK cell expansion

  2. Preparation, characterization and in vitro testing of poly(lactic-co-glycolic) acid/barium titanate nanoparticle composites for enhanced cellular proliferation.

    Science.gov (United States)

    Ciofani, Gianni; Ricotti, Leonardo; Mattoli, Virgilio

    2011-04-01

    The recent advancements in tissue engineering and, more in general, in cell-based applications, has led to an ever increasing interest toward new materials for sustained cell proliferation and differentiation. Here, the preparation and the characterization of scaffolds based on poly(lactic-co-glycolic) acid / barium titanate nanoparticle composites are presented. In vitro testing on H9C2 cell line demonstrates how the presence of the nanoparticles positively affects both the proliferation and the differentiation of this muscle-like cell line. Finally, the possibility to obtain porous scaffold and, therefore, an actual 3D culture system, is introduced.

  3. Effects of four Fusarium toxins (fumonisin B(1), alpha-zearalenol, nivalenol and deoxynivalenol) on porcine whole-blood cellular proliferation.

    Science.gov (United States)

    Luongo, D; De Luna, R; Russo, R; Severino, L

    2008-07-01

    The in vitro effects of four Fusarium toxins, fumonisin B(1) (FB(1)), alpha-zearalenol (alpha-ZEA), nivalenol (NIV) and deoxynivalenol (DON), on mitogen-induced cell proliferation were determined in swine whole-blood cultures. Considering the lack of sufficient toxicological data both on single and in combination effects, in vitro studies may contribute to risk assessment of these toxins. Incubation with increasing concentrations of FB(1) did not produce any consequence on proliferation; in contrast alpha-ZEA, NIV and DON showed an inhibitory effect. Dose-response curves for each mycotoxin were generated. NIV was found to be the most potent toxin followed by DON and alpha-ZEA. The effects of both FB(1)+alpha-ZEA and NIV+DON mixtures were also analysed to investigate possible interactions. The results indicated that combination of FB(1)+alpha-ZEA produces a synergistic inhibition of porcine cell proliferation; whereas there is no interaction between DON and NIV on porcine whole-blood proliferation, at tested concentrations.

  4. Influence of cellular ER alpha/ER beta ratio on the ER alpha-agonist induced proliferation of human T47D breast cancer cells

    NARCIS (Netherlands)

    Sotoca Covaleda, A.M.; Berg, van den H.; Vervoort, J.J.M.; Saag, van der P.; Strom, A.; Gustafsson, J.A.; Rietjens, I.M.C.M.; Murk, A.J.

    2008-01-01

    Breast cancer cells show overexpression of estrogen receptor (ER) relative to ERß compared to normal breast tissues. This observation has lead to the hypothesis that ERß may modulate the proliferative effect of ER. This study investigated how variable cellular expression ratios of the ER and ERß

  5. Hepatitis C virus E2 protein promotes human hepatoma cell proliferation through the MAPK/ERK signaling pathway via cellular receptors

    International Nuclear Information System (INIS)

    Zhao Lanjuan; Wang Lu; Ren Hao; Cao Jie; Li Li; Ke Jinshan; Qi Zhongtian

    2005-01-01

    Dysregulation of mitogen-activated protein kinase (MAPK) signaling pathways by various viruses has been shown to be responsible for viral pathogenicity. The molecular mechanism by which hepatitis C virus (HCV) infection caused human liver diseases has been investigated on the basis of abnormal intracellular signal events. Current data are very limited involved in transmembrane signal transduction triggered by HCV E2 protein. Here we explored regulation of the MAPK/extracellular signal-regulated kinase (MAPK/ERK) signaling pathway by E2 expressed in Chinese hamster oval cells. In human hepatoma Huh-7 cells, E2 specifically activated the MAPK/ERK pathway including downstream transcription factor ATF-2 and greatly promoted cell proliferation. CD81 and low density lipoprotein receptor (LDLR) on the cell surface mediated binding of E2 to Huh-7 cells. The MAPK/ERK activation and cell proliferation driven by E2 were suppressed by blockage of CD81 as well as LDLR. Furthermore, pretreatment with an upstream kinase MEK1/2 inhibitor U0126 also impaired the MAPK/ERK activation and cell proliferation induced by E2. Our results suggest that the MAPK/ERK signaling pathway triggered by HCV E2 via its receptors maintains survival and growth of target cells

  6. 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.

  7. ULTRASTRUCTURAL CHANGES OF THE NEURONAL ...

    African Journals Online (AJOL)

    ULTRASTRUCTURAL CHANGES OF THE NEURONAL COMPONENT IN THE DETRUSOR MUSCLE FOLLOWING SACRAL ROOT STIMULATION OF DECENTRALIZED ... Early sacral root electric stimulation decreased the incidence of neuronal degeneration in decentralized detrusor muscle, together with improving the ...

  8. Long non-coding RNA lnc-MX1-1 is associated with poor clinical features and promotes cellular proliferation and invasiveness in prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Chen-Yi; Gao, Yuan; Wang, Xing-Jie [Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080 (China); Ruan, Yuan [Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080 (China); Department of Urology, Shanghai General Hospital Affiliated to Nanjing Medical University, Shanghai 200080 (China); Bei, Xiao-Yu; Wang, Xiao-Hai; Jing, Yi-Feng; Zhao, Wei; Jiang, Qi [Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080 (China); Li, Jia; Han, Bang-Min [Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080 (China); Institute of Urology, Shanghai Jiao Tong University, Shanghai 200080 (China); Xia, Shu-Jie [Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080 (China); Department of Urology, Shanghai General Hospital Affiliated to Nanjing Medical University, Shanghai 200080 (China); Institute of Urology, Shanghai Jiao Tong University, Shanghai 200080 (China); Zhao, Fu-Jun, E-mail: drzhaofujun@yahoo.com [Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080 (China); Institute of Urology, Shanghai Jiao Tong University, Shanghai 200080 (China)

    2016-02-12

    Long non-coding RNAs (lncRNAs) are emerging as key molecules in human cancer genesis and progression, including prostate cancer. Large amount of lncRNAs have been found that differentially expressed between prostate cancer tissues and normal prostate tissues. Whether these lncRNAs could serve as a novel biomarker for prostate cancer diagnosis or prognosis, and their biological functions in prostate cancer need further investigation. In the present study, we identified that lncRNA lnc-MX1-1 is over-expressed in prostate cancer tissues compared with their adjacent normal prostate tissues by gene expression array profiling. The expression of lnc-MX1-1 in 60 prostate cancer cases was determined by real-time quantitative PCR and the correlations between lnc-MX1-1 expression and patients' clinical features were further analyzed. Next, we impaired lnc-MX1-1 expression using RNAi in LNCaP and 22Rv1 prostate cancer cells to explore the effects of lnc-MX1-1 on proliferation and invasiveness of the cells. Our results showed that there was a significant association between over-expression of lnc-MX1-1 and patients' clinical features such as PSA, Gleason score, metastasis, and recurrence free survival. Moreover, knockdown of lnc-MX1-1 reduced both proliferation and invasiveness of LNCaP and 22Rv1 cells. In conclusion, the results suggest that lnc-MX1-1 may serve as a potential biomarker and therapeutic target for prostate cancer. - Highlights: • LncRNA lnc-MX1-1 is up-regulated in prostate cancer. • Overexpression of lnc-MX1-1 is correlated with poor prostate cancer clinical features. • Knockdown of lnc-MX1-1 reduces proliferation and invasiveness of prostate cancer cells.

  9. Effects of insulin analogs and glucagon-like peptide-1 receptor agonists on proliferation and cellular energy metabolism in papillary thyroid cancer

    Directory of Open Access Journals (Sweden)

    He L

    2017-11-01

    Full Text Available Liang He,1,* Siliang Zhang,2,* Xiaowen Zhang,3 Rui Liu,2 Haixia Guan,2 Hao Zhang1 1Department of Thyroid Surgery, The First Hospital of China Medical University, Shenyang, Liaoning, 2Department of Endocrinology and Metabolism, The Endocrine Institute and The Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Hospital of China Medical University, Shenyang, Liaoning, 3Department of Endocrinology and Metabolism, Drum Tower Hospital Affiliated to Nanjing University Medical School, Nanjing, People’s Republic of China *These authors contributed equally to this work Purpose: This study was aimed to investigate the expressions of the insulin receptor (IR, insulin-like growth factor receptor (IGF-1R, and glucagon-like peptide-1 receptor (GLP-1R in normal thyroid tissue, papillary thyroid cancer (PTC tissues, and PTC cells, and to examine the possible role of insulin analogs and GLP-1R agonists in cell proliferation and energy metabolism in PTC cells.Methods: The expressions of IR, IGF-1R, and GLP-1R in PTC tissues and PTC cell lines were detected by immunohistochemistry and western blotting, respectively. Cell proliferation was evaluated by the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide assay. Levels of members of the phosphoinositol-3 kinase/AKT serine/threonine kinase (Akt and mitogen-activated protein kinase/extracellular signal-regulated kinase (Erk signaling pathways were measured by western blotting. Energy metabolism of PTC cell lines was analyzed using a Seahorse Extracellular Flux analyzer.Results: Three receptors could be detected in both PTC tissues and PTC cell lines. Expressions of IGF-1R and GLP-1R were more obvious in PTC than in normal thyroid cells. Neither insulin, four insulin analogs, and two GLP-1R agonists showed significant effects on the proliferation of PTC cells, nor did they influence the levels of Akt/p-Akt and Erk/p-Erk. None of these antidiabetic agents could change the mitochondrial

  10. Ultrastructure Processing of Macromolecular Materials.

    Science.gov (United States)

    1983-09-01

    polymers and other areas. The ultrastructure portion consists of a coordinated research effort with Profs. R. Lenz and H. Winter into the synthesis of...polymers and other areas. The ultrastructure portion consists of a coordinated research effort with Profs. R. Lenz and H. Winter into the synthesis ...further to characterize asymetric solutes and suspensoids. High pressure stu- dies of polymer liquid crystals were initiated to elucidate the

  11. Knockdown of Long Noncoding RNA TUG1 Inhibits the Proliferation and Cellular Invasion of Osteosarcoma Cells By Sponging MiR-153.

    Science.gov (United States)

    Wang, Heping; Yu, Yanzhang; Fan, Shuxin; Luo, Leifeng

    2017-04-12

    Long noncoding RNA (lncRNA) Taurine-upregulated gene 1 (TUG1) has been confirmed to be involved in the progression of various cancers, however, its mechanism of action in osteosarcoma has not been well addressed. In our study, TUG1 was overexpressed and miR-153 was downregulated in osteosarcoma tissues and cell lines. Loss-of-function assay showed that TUG1 knockdown suppressed the viability, colony formation, and invasion of osteosarcoma cells in vitro. Moreover, TUG1 was confirmed to be a miR-153 sponge. Ectopic expression of TUG1 reversed the inhibitory effect of miR-153 on the proliferation and invasion of osteosarcoma cells. Further transplantation experiment proved the carcinogenesis of TUG1 in osteosarcoma in vivo. Collectively, our study elucidated that TUG1 contributed to the osteosarcoma development by sponging miR-153. These findings may provide a novel lncRNA-targeted therapy for patients with osteosarcoma.

  12. E2F1-mediated upregulation of p19INK4d determines its periodic expression during cell cycle and regulates cellular proliferation.

    Directory of Open Access Journals (Sweden)

    Abel L Carcagno

    Full Text Available BACKGROUND: A central aspect of development and disease is the control of cell proliferation through regulation of the mitotic cycle. Cell cycle progression and directionality requires an appropriate balance of positive and negative regulators whose expression must fluctuate in a coordinated manner. p19INK4d, a member of the INK4 family of CDK inhibitors, has a unique feature that distinguishes it from the remaining INK4 and makes it a likely candidate for contributing to the directionality of the cell cycle. p19INK4d mRNA and protein levels accumulate periodically during the cell cycle under normal conditions, a feature reminiscent of cyclins. METHODOLOGY/PRINCIPAL FINDINGS: In this paper, we demonstrate that p19INK4d is transcriptionally regulated by E2F1 through two response elements present in the p19INK4d promoter. Ablation of this regulation reduced p19 levels and restricted its expression during the cell cycle, reflecting the contribution of a transcriptional effect of E2F1 on p19 periodicity. The induction of p19INK4d is delayed during the cell cycle compared to that of cyclin E, temporally separating the induction of these proliferative and antiproliferative target genes. Specific inhibition of the E2F1-p19INK4d pathway using triplex-forming oligonucleotides that block E2F1 binding on p19 promoter, stimulated cell proliferation and increased the fraction of cells in S phase. CONCLUSIONS/SIGNIFICANCE: The results described here support a model of normal cell cycle progression in which, following phosphorylation of pRb, free E2F induces cyclin E, among other target genes. Once cyclinE/CDK2 takes over as the cell cycle driving kinase activity, the induction of p19 mediated by E2F1 leads to inhibition of the CDK4,6-containing complexes, bringing the G1 phase to an end. This regulatory mechanism constitutes a new negative feedback loop that terminates the G1 phase proliferative signal, contributing to the proper coordination of the cell

  13. Over-expression of 60s ribosomal L23a is associated with cellular proliferation in SAG resistant clinical isolates of Leishmania donovani.

    Directory of Open Access Journals (Sweden)

    Sanchita Das

    Full Text Available Sodium antimony gluconate (SAG unresponsiveness of Leishmania donovani (Ld had effectively compromised the chemotherapeutic potential of SAG. 60s ribosomal L23a (60sRL23a, identified as one of the over-expressed protein in different resistant strains of L.donovani as observed with differential proteomics studies indicates towards its possible involvement in SAG resistance in L.donovani. In the present study 60sRL23a has been characterized for its probable association with SAG resistance mechanism.The expression profile of 60s ribosomal L23a (60sRL23a was checked in different SAG resistant as well as sensitive strains of L.donovani clinical isolates by real-time PCR and western blotting and was found to be up-regulated in resistant strains. Ld60sRL23a was cloned, expressed in E.coli system and purified for raising antibody in swiss mice and was observed to have cytosolic localization in L.donovani. 60sRL23a was further over-expressed in sensitive strain of L.donovani to check its sensitivity profile against SAG (Sb V and III and was found to be altered towards the resistant mode.This study reports for the first time that the over expression of 60sRL23a in SAG sensitive parasite decreases the sensitivity of the parasite towards SAG, miltefosine and paramomycin. Growth curve of the tranfectants further indicated the proliferative potential of 60sRL23a assisting the parasite survival and reaffirming the extra ribosomal role of 60sRL23a. The study thus indicates towards the role of the protein in lowering and redistributing the drug pressure by increased proliferation of parasites and warrants further longitudinal study to understand the underlying mechanism.

  14. miRNA array analysis determines miR-205 is overexpressed in head and neck squamous cell carcinoma and enhances cellular proliferation

    Directory of Open Access Journals (Sweden)

    Howard JD

    2013-08-01

    Full Text Available MicroRNAs (miRNAs play a critical role in cell cycle and pro-survival signal regulation. Consequently, their deregulation can enhance tumorigenesis and cancer progression. In the current investigation, we determined whether cancer- or human papillomavirus (HPV-specific miRNA deregulation could further elucidate signal transduction events unique to head and neck squamous cell carcinoma (HNSCC. Twenty-nine newly diagnosed HNSCC tumors (HPV-positive: 14, HPV-negative: 15 and four normal mucosa samples were analyzed for global miRNA expression. Differential miRNA expression analysis concluded HNSCC is characterized by a general upregulation of miRNAs compared to normal mucosa. Additionally, miR-449a and miR-129-3p were statistically significant miRNAs differentially expressed between HPV-positive and HPV-negative HNSCC. The upregulation of miR-449a was also validated within an independent dataset obtained from TCGA containing 279 HNSCCs and 39 normal adjacent mucosa samples. To gain a better understanding of miRNA-mediated cell cycle deregulation in HNSCC, we functionally evaluated miR-205, a transcript upregulated in our cancer-specific analysis and a putative regulator of E2F1. Modulation of miR-205 with a miRNA mimic and inhibitor revealed miR-205 is capable of regulating E2F1 expression in HNSCC and overexpression of this transcript enhances proliferation. This study demonstrates miRNA expression is highly deregulated in HNSCC and functional evaluations of these miRNAs may reveal novel HPV context dependent mechanisms in this disease.

  15. Ultrastructure of right ventricular myocardium subjected to acute pressure load.

    Science.gov (United States)

    Mühlfeld, C; Coulibaly, M; Dörge, H; Sellin, C; Liakopoulos, O; Ballat, C; Richter, J; Schoendube, F

    2004-12-01

    Ultrastructural data on acute right ventricular pressure load in pigs are rare. In control (n = 7) and banding groups (n = 6), right ventricular pressure (micromanometry) and function (sonomicrometry) were measured. Right ventricular pressure was increased 2.5-fold in the banding group by pulmonary artery constriction. Right ventricular biopsies were taken at baseline and after 6 h and processed for electron microscopy. Parameters of cellular injury were determined stereologically. Three perfusion -fixed hearts were investigated qualitatively in each group. Stereology revealed an increase in the sarcoplasmic volume fraction and the cellular edema index in the banding group ( p < 0.05). Mitochondrial surface-to-volume ratio and volume fraction did not show significant alterations. Subendocardial edema and small amounts of severely injured myocytes were observed in the perfusion-fixed hearts after banding. Ultrastructure was normal in controls. After an initial increase, the right ventricular work index declined progressively in the banding group but remained unchanged in controls. Ultrastructural alterations resulting from acute right ventricular pressure load were characterized by edema of subendocardial myocytes and single cell necrosis. Focal adrenergic overstimulation and mechanical stress are probably more relevant in the pathogenesis of these lesions than ischemia.

  16. Ultrastructural patterns of Helicobacter pylori.

    OpenAIRE

    Caselli, M; Aleotti, A; Boldrini, P; Ruina, M; Alvisi, V

    1993-01-01

    Ultrastructural morphology of the bacterial bodies was studied in 40 Helicobacter pylori positive cases. Two bacterial patterns were identified, which were associated with different modes of contact with the epithelial cells and possibly with different stages of the natural history of the infection.

  17. Ultrastructure, macromolecules, and evolution

    CERN Document Server

    Dillon, Lawrence S

    1981-01-01

    Thus far in the history of biology, two, and only two, fundamental principles have come to light that pervade and unify the entire science-the cell theory and the concept of evolution. While it is true that recently opened fields of inves­ tigation have given rise to several generalizations of wide impact, such as the universality of DNA and the energetic dynamics of ecology, closer inspection reveals them to be part and parcel of either of the first two mentioned. Because in the final analysis energy can act upon an organism solely at the cellular level, its effects may be perceived basically to represent one facet of cell me­ tabolism. Similarly, because the DNA theory centers upon the means by which cells build proteins and reproduce themselves, it too proves to be only one more, even though an exciting, aspect of the cell theory. In fact, if the matter is given closer scrutiny, evolution itself can be viewed as being a fundamental portion of the cell concept, for its effects arise only as a consequence ...

  18. Ultrastructural Characterization of Zika Virus Replication Factories

    Directory of Open Access Journals (Sweden)

    Mirko Cortese

    2017-02-01

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

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

    African Journals Online (AJOL)

    AJB SERVER

    2006-12-29

    Dec 29, 2006 ... cardiocytes: an immunocytochemical and ultrastructural morphometric comparative study. Ann Anat (in press). Gilloteaux J, Jennes L, Menu R, Vanderhaeghen JJ (1991). Ultrastructural immunolocalization of the atrial natriuretic factor pathways in fetal, neonatal, and adult Syrian hamsters: from the atrial.

  20. 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.

  1. 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)

  2. Ultrastructural assessment of cellulite morphology: clues to a therapeutic strategy?

    Science.gov (United States)

    Omi, Tokuya; Sato, Shigeru; Kawana, Seiji

    2013-01-01

    Cellulite is a problematic condition affecting mostly women, characterized by a bumpy or nodular skin surface. Recent approaches with laser treatment have offered some promise. The present study sought to identify possible targets for laser treatment or light therapy through an ultrastructural investigation of the condition. Study subjects comprised 7 healthy Japanese female volunteers (Age range 37-46 yr, average 38.4) with cellulite, graded on the 4-point Nurnberger-Muller cellulite severity scale. Four patients were at grade 2 and 3 at grade 3. Three millimeter punch biopsies were obtained and routinely processed for light and transmission electron microscopy. Microphotography of specimens from cellulite patients demonstrated the presence of fibrotic septa which divided up larger clusters of adipose tissue into smaller packets, with the septa acting as a tethering system, thus producing the typical dimpling pattern. Ultrastructural findings showed proliferation of collagen and elastic fibers down into the cellulite tissue with compression of capillaries and congestion of arterioles, resulting in poor blood flow. The histological and ultrastructural findings of cellulite clearly distinguish the condition from simple fat deposition. The remodeling of the fat layer into lobulated packets of lipocytes sequestered by fibrotic septa with a high proportion of elastic fibers would suggest the use of a fiber-based interstitial laser-assisted lipolysis system at an appropriate wavelength which might offer benefits through disruption of the septae through a photomechanical effect and lipolysis of the sequestered lipocytes. This could be followed by a course of near-infrared phototherapy to accelerate clearance of freed lipid and debris and reestablish the vascular system.

  3. Ultrastructural Localization and Molecular Associations of HCV Capsid Protein in Jurkat T Cells.

    Science.gov (United States)

    Fernández-Ponce, Cecilia; Durán-Ruiz, Maria C; Narbona-Sánchez, Isaac; Muñoz-Miranda, Juan P; Arbulo-Echevarria, Mikel M; Serna-Sanz, Antonio; Baumann, Christian; Litrán, Rocío; Aguado, Enrique; Bloch, Wilhelm; García-Cozar, Francisco

    2017-01-01

    Hepatitis C virus core protein is a highly basic viral protein that multimerizes with itself to form the viral capsid. When expressed in CD4 + T lymphocytes, it can induce modifications in several essential cellular and biological networks. To shed light on the mechanisms underlying the alterations caused by the viral protein, we have analyzed HCV-core subcellular localization and its associations with host proteins in Jurkat T cells. In order to investigate the intracellular localization of Hepatitis C virus core protein, we have used a lentiviral system to transduce Jurkat T cells and subsequently localize the protein using immunoelectron microscopy techniques. We found that in Jurkat T cells, Hepatitis C virus core protein mostly localizes in the nucleus and specifically in the nucleolus. In addition, we performed pull-down assays combined with Mass Spectrometry Analysis, to identify proteins that associate with Hepatitis C virus core in Jurkat T cells. We found proteins such as NOLC1, PP1γ, ILF3, and C1QBP implicated in localization and/or traffic to the nucleolus. HCV-core associated proteins are implicated in RNA processing and RNA virus infection as well as in functions previously shown to be altered in Hepatitis C virus core expressing CD4 + T cells, such as cell cycle delay, decreased proliferation, and induction of a regulatory phenotype. Thus, in the current work, we show the ultrastructural localization of Hepatitis C virus core and the first profile of HCV core associated proteins in T cells, and we discuss the functions and interconnections of these proteins in molecular networks where relevant biological modifications have been described upon the expression of Hepatitis C virus core protein. Thereby, the current work constitutes a necessary step toward understanding the mechanisms underlying HCV core mediated alterations that had been described in relevant biological processes in CD4 + T cells.

  4. Ultrastructural Localization and Molecular Associations of HCV Capsid Protein in Jurkat T Cells

    Directory of Open Access Journals (Sweden)

    Cecilia Fernández-Ponce

    2018-01-01

    Full Text Available Hepatitis C virus core protein is a highly basic viral protein that multimerizes with itself to form the viral capsid. When expressed in CD4+ T lymphocytes, it can induce modifications in several essential cellular and biological networks. To shed light on the mechanisms underlying the alterations caused by the viral protein, we have analyzed HCV-core subcellular localization and its associations with host proteins in Jurkat T cells. In order to investigate the intracellular localization of Hepatitis C virus core protein, we have used a lentiviral system to transduce Jurkat T cells and subsequently localize the protein using immunoelectron microscopy techniques. We found that in Jurkat T cells, Hepatitis C virus core protein mostly localizes in the nucleus and specifically in the nucleolus. In addition, we performed pull-down assays combined with Mass Spectrometry Analysis, to identify proteins that associate with Hepatitis C virus core in Jurkat T cells. We found proteins such as NOLC1, PP1γ, ILF3, and C1QBP implicated in localization and/or traffic to the nucleolus. HCV-core associated proteins are implicated in RNA processing and RNA virus infection as well as in functions previously shown to be altered in Hepatitis C virus core expressing CD4+ T cells, such as cell cycle delay, decreased proliferation, and induction of a regulatory phenotype. Thus, in the current work, we show the ultrastructural localization of Hepatitis C virus core and the first profile of HCV core associated proteins in T cells, and we discuss the functions and interconnections of these proteins in molecular networks where relevant biological modifications have been described upon the expression of Hepatitis C virus core protein. Thereby, the current work constitutes a necessary step toward understanding the mechanisms underlying HCV core mediated alterations that had been described in relevant biological processes in CD4+ T cells.

  5. 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...

  6. Study on the effects of gradient mechanical pressures on the proliferation, apoptosis, chondrogenesis and hypertrophy of mandibular condylar chondrocytes in vitro.

    Science.gov (United States)

    Li, Hui; Huang, Linjian; Xie, Qianyang; Cai, Xieyi; Yang, Chi; Wang, Shaoyi; Zhang, Min

    2017-01-01

    To investigate the effects of gradient mechanical pressure on chondrocyte proliferation, apoptosis, and the expression of markers of chondrogenesis and chondrocyte hypertrophy. Mandibular condylar chondrocytes from 5 rabbits were cultured in vitro, and pressed with static pressures of 50kPa, 100kPa, 150kPa and 200kPa for 3h, respectively. The chondrocytes cultured without pressure (0kPa) were used as control. Cell proliferation, apoptosis, and the expression of aggrecan (AGG), collagen II (COL2), collagen X (COL10), alkaline phosphatase (ALP) were investigated. Ultrastructures of the pressurized chondrocytes under transmission electron microscopy (TEM) were observed. Chondrocyte proliferation increased at 100kPa and decreased at 200kPa. Chondrocyte apoptosis increased with peak pressure at 200kPa in a dose-dependent manner. Chondrocyte necrosis increased at 200kPa. The expression of AGG increased at 200kPa. The expression of COL2 decreased at 50kPa and increased at 150kPa. The expression of COL10 and ALP increased at 150kPa. Ultrastructure of the pressurized chondrocytes under TEM showed: at 100kPa, cells were enlarged with less cellular microvillus and a bigger nucleus; at 200kPa, cells shrank with the sign of apoptosis, and apoptosis cells were found. The mechanical loading of 150kPa is the moderate pressure for chondrocyte: cell proliferation and apoptosis is balanced, necrosis is reduced, and chondrogenesis and chondrocyte hypertrophy are promoted. When the pressure is lower, chondrogenesis and chondrocyte hypertrophy are inhibited. At 200kPa, degeneration of cartilage is implied. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Nuclear proliferation

    International Nuclear Information System (INIS)

    Stencel, S.

    1978-01-01

    The terms and reactions to President Carter's nuclear policy, culminating in the 1978 Nuclear Non-Proliferation Act, are reviewed and analyzed. The new law increases restrictions on nuclear exports, encourages continued use of light water reactors in preference to plutonium-fueled reactors, and emphasizes technical solutions to proliferation problems. Critics of the law point out that it will hurt U.S. trade unfairly, that other countries do not have as many fuel options as the U.S. has, and that nuclear sales have as many political and economic as technical solutions. Compromise areas include new international safety guidelines, the possibility of an international nuclear fuel bank, and a willingness to consider each case on its merits. 21 references

  8. Cellular automata

    CERN Document Server

    Codd, E F

    1968-01-01

    Cellular Automata presents the fundamental principles of homogeneous cellular systems. This book discusses the possibility of biochemical computers with self-reproducing capability.Organized into eight chapters, this book begins with an overview of some theorems dealing with conditions under which universal computation and construction can be exhibited in cellular spaces. This text then presents a design for a machine embedded in a cellular space or a machine that can compute all computable functions and construct a replica of itself in any accessible and sufficiently large region of t

  9. The influence of silicon on barley growth, photosynthesis and ultra-structure under chromium stress.

    Science.gov (United States)

    Ali, Shafaqat; Farooq, Muhammad Ahsan; Yasmeen, Tahira; Hussain, Sabir; Arif, Muhammad Saleem; Abbas, Farhat; Bharwana, Saima Aslam; Zhang, Guoping

    2013-03-01

    Silicon (Si) is generally considered as a benefic element for higher plants, especially for those grown under abiotic stressed environments. Current study is carried out in a hydroponic experiment to analyze the effect of Si application on barley growth, photosynthesis and ultra-structure under chromium (Cr) stress. The treatments consisted of three Si (0, 1 and 2mM) and two Cr (0 and 100 μM) levels. The results showed that Si application at both levels enhanced plant growth relative to the control, and alleviated Cr toxicity, reflected by significant increase in growth and photosynthetic parameters, such as SPAD value, net photosynthetic rate (P(n)), cellular CO(2) concentration (C(i)), stomatal conductance (G(s)) and transpiration rate (T(r)), and chlorophyll fluorescence efficiency (Fv/Fm), with 2mM Si having greater effect than 1mM Si. Cr stress caused ultra-structural disorders in leaves, such as uneven swelling of chloroplast, increased amount of plastoglobuli, disintegrated and disappeared thylakoid membranes, increased size and number of starch granules in leaves, and root ultra-structural modification, including increased vacuolar size, presence of Cr metal in cell walls and vacuoles, disruption and disappearance of nucleus. Exogenous Si alleviated these ultra-structural disorders both in roots and leaves. Apparently, Si and Cr behaved antagonistically, indicating that Si could be a candidate for Cr detoxification in crops under Cr-contaminated soil. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Ultrastructure of Reissner's membrane in the rabbit

    DEFF Research Database (Denmark)

    Qvortrup, K; Rostgaard, J; Bretlau, P

    1994-01-01

    The ultrastructure of Reissner's membrane in the rabbit is described following vascular perfusion-fixation of live, anesthetized and artificially respirated healthy animals. A new and improved technique of fixation is employed that includes a pressure feedback controlled peristaltic pump and an o......The ultrastructure of Reissner's membrane in the rabbit is described following vascular perfusion-fixation of live, anesthetized and artificially respirated healthy animals. A new and improved technique of fixation is employed that includes a pressure feedback controlled peristaltic pump...

  11. Oxidative stress induced pulmonary endothelial cell proliferation is ...

    African Journals Online (AJOL)

    Cellular hyper-proliferation, endothelial dysfunction and oxidative stress are hallmarks of the pathobiology of pulmonary hypertension. Indeed, pulmonary endothelial cells proliferation is susceptible to redox state modulation. Some studies suggest that superoxide stimulates endothelial cell proliferation while others have ...

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

    Directory of Open Access Journals (Sweden)

    Visitación T. Conforti

    2017-11-01

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

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

    African Journals Online (AJOL)

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

  14. Calcium signaling and cell proliferation.

    Science.gov (United States)

    Pinto, Mauro Cunha Xavier; Kihara, Alexandre Hiroaki; Goulart, Vânia A M; Tonelli, Fernanda M P; Gomes, Katia N; Ulrich, Henning; Resende, Rodrigo R

    2015-11-01

    Cell proliferation is orchestrated through diverse proteins related to calcium (Ca(2+)) signaling inside the cell. Cellular Ca(2+) influx that occurs first by various mechanisms at the plasma membrane, is then followed by absorption of Ca(2+) ions by mitochondria and endoplasmic reticulum, and, finally, there is a connection of calcium stores to the nucleus. Experimental evidence indicates that the fluctuation of Ca(2+) from the endoplasmic reticulum provides a pivotal and physiological role for cell proliferation. Ca(2+) depletion in the endoplasmatic reticulum triggers Ca(2+) influx across the plasma membrane in an phenomenon called store-operated calcium entries (SOCEs). SOCE is activated through a complex interplay between a Ca(2+) sensor, denominated STIM, localized in the endoplasmic reticulum and a Ca(2+) channel at the cell membrane, denominated Orai. The interplay between STIM and Orai proteins with cell membrane receptors and their role in cell proliferation is discussed in this review. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Ultrastructure of book gill development in embryos and first instars of the horseshoe crab Limulus polyphemus L. (Chelicerata, Xiphosura)

    Science.gov (United States)

    2012-01-01

    Background The transmission electron microscope (TEM) is used for the first time to study the development of book gills in the horseshoe crab. Near the end of the nineteenth century the hypothesis was presented for homology and a common ancestry for horseshoe crab book gills and arachnid book lungs. The present developmental study and the author's recent ones of book gills (SEM) and scorpion book lungs (TEM) are intended to clarify early histological work and provide new ultrastructural details for further research and for hypotheses about evolutionary history and relationships. Results The observations herein are in agreement with earlier reports that the book gill lamellae are formed by proliferation and evagination of epithelial cells posterior to opisthosomal branchial appendages. A cartilage-like endoskeleton is produced in the base of the opisthosomal appendages. The lamellar precursor cells in the appendage base proliferate, migrate outward and secrete the lamellar cuticle from their apical surface. A series of external, posteriorly-directed lamellae is formed, with each lamella having a central channel for hemolymph and pillar-type space holders formed from cells of the opposed walls. This repeated, page-like pattern results also in water channels (without space holders) between the sac-like hemolymph lamellae. Conclusions The developmental observations herein and in an earlier study (TEM) of scorpion book lungs show that the lamellae in book gills and book lungs result from some similar activities and features of the precursor epithelial cells: proliferation, migration, alignment and apical/basal polarity with secretion of cuticle from the apical surface and the basal surface in contact with hemolymph. These cellular similarities and the resulting book-like structure suggest a common ancestry, but there are also substantial developmental differences in producing these organs for gas exchange in the different environments, aqueous and terrestrial. For

  16. Ultrastructure of book gill development in embryos and first instars of the horseshoe crab Limulus polyphemus L. (Chelicerata, Xiphosura

    Directory of Open Access Journals (Sweden)

    Farley Roger D

    2012-03-01

    Full Text Available Abstract Background The transmission electron microscope (TEM is used for the first time to study the development of book gills in the horseshoe crab. Near the end of the nineteenth century the hypothesis was presented for homology and a common ancestry for horseshoe crab book gills and arachnid book lungs. The present developmental study and the author's recent ones of book gills (SEM and scorpion book lungs (TEM are intended to clarify early histological work and provide new ultrastructural details for further research and for hypotheses about evolutionary history and relationships. Results The observations herein are in agreement with earlier reports that the book gill lamellae are formed by proliferation and evagination of epithelial cells posterior to opisthosomal branchial appendages. A cartilage-like endoskeleton is produced in the base of the opisthosomal appendages. The lamellar precursor cells in the appendage base proliferate, migrate outward and secrete the lamellar cuticle from their apical surface. A series of external, posteriorly-directed lamellae is formed, with each lamella having a central channel for hemolymph and pillar-type space holders formed from cells of the opposed walls. This repeated, page-like pattern results also in water channels (without space holders between the sac-like hemolymph lamellae. Conclusions The developmental observations herein and in an earlier study (TEM of scorpion book lungs show that the lamellae in book gills and book lungs result from some similar activities and features of the precursor epithelial cells: proliferation, migration, alignment and apical/basal polarity with secretion of cuticle from the apical surface and the basal surface in contact with hemolymph. These cellular similarities and the resulting book-like structure suggest a common ancestry, but there are also substantial developmental differences in producing these organs for gas exchange in the different environments, aqueous

  17. Aerodynamics and pollen ultrastructure in Ephedra.

    Science.gov (United States)

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

    2015-03-01

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

  18. Ultrastructural changes in porcine mammary tissue during lactogenesis.

    Science.gov (United States)

    Kensinger, R S; Collier, R J; Bazer, F W

    1986-01-01

    Ultrastructural changes occurring in porcine mammary tissue were characterised between Day 90 of pregnancy and Day 4 of lactation. Porcine mammary tissue on Day 90 of pregnancy was composed of alveoli which contained negligible to moderate amounts of secretion. Epithelial cells of these alveoli were relatively undifferentiated. The appearance and distribution of cellular organelles suggested that mammary epithelial differentiation had been initiated by Day 105 of pregnancy in the pig. A further increase in intracellular lipid droplets and granular endoplasmic reticulum suggested that differentiation had progressed by Day 112. On the day of parturition, secretions within the alveolar lumina assumed the appearance of normal milk (as opposed to colostrum) and the epithelia displayed a distinct cellular polarity characteristic of lactating mammary tissue. By Day 4 of lactation, differentiation of epithelial cells appeared to be complete, with dilated cisternae of the granular endoplasmic reticulum and with numerous secretory vesicles. Elongated microvilli were present and numerous cells contained lipid droplets which were being extruded into the lumina. Data from this and previous studies indicate that lactogenesis in the pig occurs in two stages. Stage 1 occurs between Days 90 and 105 of pregnancy, and Stage 2 between Days 112 of pregnancy and early lactation when the predominant feature is active milk secretion. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:3429308

  19. 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)

  20. Ultrastructural damage of Trypanosoma cruzi epimastigotes exposed to decomplemented immune sera.

    Science.gov (United States)

    Fernández-Presas, A M; Zavala, J T; Fauser, I B; Merchant, M T; Guerrero, L R; Willms, K

    2001-08-01

    The susceptibility of Trypanosoma cruzi epimastigotes to lysis by normal or immune sera in a complement-dependent reaction has been reported, but the effects induced directly by immune serum depleted of complement remain unstudied. The aim of this work was to study the ultrastructural alterations induced in T. cruzi epimastigotes by immune mouse or rabbit sera with or without complement. A local isolate of T. cruzi (Queretaro) was used in all experiments. Immune sera were raised in both mouse and rabbit by immunization with T. cruzi epimastigote antigens. Light microscopy showed intense agglutination of epimastigotes when incubated with decomplemented mouse or rabbit immune sera. A distinctive ultrastructural feature of this agglutination pattern was the fusion of plasma membranes and a pattern of intercrossing between subpellicular microtubules. Agglutination was associated with fragmentation of nuclear membranes and swelling of cytoplasm, Golgi cisternae, endoplasmic reticulum, mitochondria and kinetoplast membranes. Agglutinated parasites also incorporated trypan blue stain. Results of [3H]-thymidine incorporation confirmed that epimastigotes exposed to specific antibodies in the absence of complement were incapable of proliferating. Ultrastructural changes observed in epimastigote micrographs incubated with decomplemented immune mouse sera were statistically significant (P<0.001) when compared with results obtained from images after incubation with decomplemented normal mouse sera.

  1. 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

  2. Malignant mesothelioma: ultrastructural distinction from adenocarcinoma.

    Science.gov (United States)

    Warhol, M J; Hickey, W F; Corson, J M

    1982-06-01

    Mesotheliomas and metastatic adenocarcinomas involving the pleura are frequently difficult to distinguish by light-microscopic and histochemical methods. In a double-blind study, we have compared ultrastructural features of 10 mesotheliomas of epithelial type and 10 adenocarcinomas from the lung, breast, and upper GI tract, i.e., sites known to give rise to metastases which mimic mesothelioma. Mesotheliomas were observed to have a significantly greater microvillus length/diameter ratio (LDR) than adenocarcinomas (p less than 0.01) and more abundant intermediate filaments (p less than 0.001). Mesotheliomas had more complex microvilli than adenocarcinomas, whereas adenocarcinomas had rootlets (2/10 cases) and lamellar inclusion bodies (2/10 cases), both of which were absent in the mesotheliomas. This study provides quantitative and qualitative ultrastructural features of potential utility in the differential diagnosis of pleural mesotheliomas and adenocarcinomas.

  3. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  5. Real space flight travel is associated with ultrastructural changes, cytoskeletal disruption and premature senescence of HUVEC.

    Science.gov (United States)

    Kapitonova, M Y; Muid, S; Froemming, G R A; Yusoff, W N W; Othman, S; Ali, A M; Nawawi, H M

    2012-12-01

    Microgravity, hypergravity, vibration, ionizing radiation and temperature fluctuations are major factors of outer space flight affecting human organs and tissues. There are several reports on the effect of space flight on different human cell types of mesenchymal origin while information regarding changes to vascular endothelial cells is scarce. Ultrastructural and cytophysiological features of macrovascular endothelial cells in outer space flight and their persistence during subsequent culturing were demonstrated in the present investigation. At the end of the space flight, endothelial cells displayed profound changes indicating cytoskeletal lesions and increased cell membrane permeability. Readapted cells of subsequent passages exhibited persisting cytoskeletal changes, decreased metabolism and cell growth indicating cellular senescence.

  6. Comparative ultrastructural analyses of platelets and fibrin networks using the murine model of asthma.

    Science.gov (United States)

    Pretorius, E; Ekpo, O E; Smit, E

    2007-10-01

    The murine Balb/c asthma model has been used successfully for a number of in vivo immunological applications and for testing novel therapeutics, and it is a reliable, clinically relevant facsimile of the human disease. Here we investigate whether this model can be used to study other components of the human body, e.g. ultrastructure. In particular, we investigate the effect of the phytomedicine Euphorbia hirta (used to treat asthma), on the ultrastructure of fibrin as well as platelets, cellular structures that both play an important role in the coagulation process. Hydrocortisone is used as positive control. Ultrastructure of the fibrin networks and platelets of control mice were compared to mice that were asthmatic, treated with two concentrations of hydrocortisone and one concentration of the plant material. Results indicate control mice possess major, thick fibers and minor thin fibers as well as tight round platelet aggregates with typical pseudopodia formation. Minor fibers of asthmatic mice have a netlike appearance covering the major fibers, while the platelets seem to form loosely connected, granular aggregates. Both concentrations of hydrocortisone make the fibrin more fragile and that platelet morphology changes form a tight platelet aggregate to a more granular aggregate not closely fused to each other. We conclude that E. hirta does not impact on the fragility of the fibrin and that it prevents the minor fibers to form the dense netlike layer over the major fibers, as is seen in untreated asthmatic mice. This ultrastructural morphology might give us better insight into asthma and the possible new treatment regimes.

  7. Cellular proliferation rate and insulin-like growth factor binding protein (IGFBP)-2 and IGFBP-3 and estradiol receptor alpha expression in the mammary gland of dairy heifers naturally infected with gastrointestinal nematodes during development.

    Science.gov (United States)

    Perri, A F; Dallard, B E; Baravalle, C; Licoff, N; Formía, N; Ortega, H H; Becú-Villalobos, D; Mejia, M E; Lacau-Mengido, I M

    2014-01-01

    Mammary ductal morphogenesis during prepuberty occurs mainly in response to insulin-like growth factor-1 (IGF-1) and estradiol stimulation. Dairy heifers infected with gastrointestinal nematodes have reduced IGF-1 levels, accompanied by reduced growth rate, delayed puberty onset, and lower parenchyma-stroma relationship in their mammary glands. Immunohistochemical studies were undertaken to determine variations in cell division rate, IGF-1 system components, and estradiol receptors (ESR) during peripubertal development in the mammary glands of antiparasitic-treated and untreated Holstein heifers naturally infected with gastrointestinal nematodes. Mammary biopsies were taken at 20, 30, 40, and 70 wk of age. Proliferating cell nuclear antigen immunolabeling, evident in nuclei, tended to be higher in the parenchyma of the glands from treated heifers than in those from untreated. Insulin-like growth factor binding proteins (IGFBP) type 2 and type 3 immunolabeling was cytoplasmic and was evident in stroma and parenchyma. The IGFBP2-labeled area was lower in treated than in untreated heifers. In the treated group, a maximal expression of this protein was seen at 40 wk of age, whereas in the untreated group the labeling remained constant. No differences were observed for IGFBP3 between treatment groups or during development. Immunolabeling for α ESR (ESR1) was evident in parenchymal nuclei and was higher in treated than in untreated heifers. In the treated group, ESR1 peaked at 30 wk of age and then decreased. These results demonstrate that the parasite burden in young heifers negatively influence mammary gland development, affecting cell division rate and parameters related to estradiol and IGF-1 signaling in the gland. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  8. Markers of cellular senescence. Telomere shortening as a marker of cellular senescence.

    Science.gov (United States)

    Bernadotte, Alexandra; Mikhelson, Victor M; Spivak, Irina M

    2016-01-01

    The cellular senescence definition comes to the fact of cells irreversible proliferation disability. Besides the cell cycle arrest, senescent cells go through some morphological, biochemical, and functional changes which are the signs of cellular senescence. The senescent cells (including replicative senescence and stress-induced premature senescence) of all the tissues look alike. They are metabolically active and possess the set of characteristics in vitro and in vivo, which are known as biomarkers of aging and cellular senescence. Among biomarkers of cellular senescence telomere shortening is a rather elegant frequently used biomarker. Validity of telomere shortening as a marker for cellular senescence is based on theoretical and experimental data.

  9. Form follows function: ultrastructure of different morphotypes of Physarum polycephalum

    Science.gov (United States)

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

    2018-04-01

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

  10. Tridimensional ultrastructure and glycolipid pattern studies of Trypanosoma dionisii.

    Science.gov (United States)

    Oliveira, Miriam Pires de Castro; Ramos, Thiago Cesar Prata; Pinheiro, Adriana Maria V N; Bertini, Silvio; Takahashi, Helio Kiyoshi; Straus, Anita Hilda; Haapalainen, Edna Freymuller

    2013-12-01

    Trypanosoma (Schizotrypanum) dionisii is a non-pathogenic bat trypanosome closely related to Trypanosoma cruzi, the etiological agent of Chaga's disease. Both kinetoplastids present similar morphological stages and are able to infect mammalian cells in culture. In the present study we examined 3D ultrastructure aspects of the two species by serial sectioning epimastigote and trypomastigote forms, and identified common carbohydrate epitopes expressed in T. dionisii, T. cruzi and Leishmania major. A major difference in 3D morphology was that T. dionisii epimastigote forms present larger multivesicular structures, restricted to the parasite posterior region. These structures could be related to T. cruzi reservosomes and are also rich in cruzipain, the major cysteine-proteinase of T. cruzi. We analyzed the reactivity of two monoclonal antibodies: MEST-1 directed to galactofuranose residues of glycolipids purified from Paracoccidioides brasiliensis, and BST-1 directed to glycolipids purified from T. cruzi epimastigotes. Both antibodies were reactive with T. dionisii epimastigotes by indirect immunofluorescense, but we noted differences in the location and intensity of the epitopes, when compared to T. cruzi. In summary, despite similar features in cellular structure and life cycle of T. dionisii and T. cruzi, we observed a unique morphological characteristic in T. dionisii that deserves to be explored. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Ultrastructural changes of Saccharomyces cerevisiae in response to ethanol stress.

    Science.gov (United States)

    Ma, Manli; Han, Pei; Zhang, Ruimin; Li, Hao

    2013-09-01

    In the fermentative process using Saccharomyces cerevisiae to produce bioethanol, the performance of cells is often compromised by the accumulation of ethanol. However, the mechanism of how S. cerevisiae responds against ethanol stress remains elusive. In the current study, S. cerevisiae cells were cultured in YPD (yeast extract - peptone - dextrose) medium containing various concentrations of ethanol (0%, 2.5%, 5%, 7.5%, 10%, and 15% (v/v)). Compared with the control group without ethanol, the mean cell volume of S. cerevisiae decreased significantly in the presence of 7.5% and 10% ethanol after incubation for 16 h (P < 0.05), and in the presence of 15% ethanol at all 3 sampling time points (1, 8, and 16 h) (P < 0.05). The exposure of S. cerevisiae cells to ethanol also led to an increase in malonyldialdehyde content (P < 0.05) and a decrease in sulfhydryl group content (P < 0.05). Moreover, the observations through transmission electron microscopy enabled us to relate ultrastructural changes elicited by ethanol with the cellular stress physiology. Under ethanol stress, the integrity of the cell membrane was compromised. The swelling or distortion of mitochondria together with the occurrence of a single and large vacuole was correlated with the addition of ethanol. These results suggested that the cell membrane is one of the targets of ethanol, and the degeneration of mitochondria promoted the accumulation of intracellular reactive oxygen species.

  12. Gemcitabine resistance in breast cancer cells regulated by PI3K/AKT-mediated cellular proliferation exerts negative feedback via the MEK/MAPK and mTOR pathways

    Directory of Open Access Journals (Sweden)

    Yang XL

    2014-06-01

    ability of 231/Gem cells. Western blot analysis showed that treatment with a PI3K/AKT inhibitor decreased the expression levels of p-AKT, p-MEK, p-mTOR, and p-P70S6K; however, treatments with either MEK/MAPK or mTOR inhibitor significantly increased p-AKT expression. Thus, our data suggest that gemcitabine resistance in breast cancer cells is mainly mediated by activation of the PI3K/AKT signaling pathway. This occurs through elevated expression of p-AKT protein to promote cell proliferation and is negatively regulated by the MEK/MAPK and mTOR pathways. Keywords: chemoresistance, gemcitabine, breast cancer

  13. Ultrastructural changes in goat interspecies and intraspecies reconstructed early embryos

    DEFF Research Database (Denmark)

    Tao, Yong; Gheng, Lizi; Zhang, Meiling

    2008-01-01

    The low efficiency of somatic cell nuclear transfer may be related to the ultrastructural deviations of reconstructed embryos. The present study investigated ultrastructural differences between in vivo-produced and cloned goat embryos, including intra- and interspecies embryos. Goat ear fibroblas...

  14. Ultrastructural liver changes in the experimental thyrotoxicosis

    Directory of Open Access Journals (Sweden)

    Nadiya Vasylivna Pasyechko

    2017-09-01

    Full Text Available Aim of the study is to evaluate ultrastructural changes of rat liver in experimental thyrotoxicosis. For the study, 36 male rats have been utilized, weighing approximately 150-190 g, which were divided into three groups: the first, control group (12 animals was composed of healthy rats that received intragastric sodium chloride 0.9% solution, the second group (12 animals – animals with experimental thyrotoxicosis, which received intragastric solution of L-thyroxine at the rate of 200 μg/kg for 2 weeks, and the third group (12 animals – rats with experimental thyrotoxicosis, which received intragastric solution of L-thyroxine at the rate of 200 μg/kg for 4 weeks. For electron-microscopic studies small pieces of liver tissue were taken at the end of the 2nd and 4th weeks of the experiment. The material was studied and documented in electron micrographs by using a TEM-125K electron microscope. In experiment in white male rats the electron-microscopic state of the liver in thyrotoxicosis has been studied. It has been established that thyrotoxicosis is accompanied by the significant changes of the hepatocytes ultrastructure, blood and bile capillaries. Experimental thyrotoxicosis causes significant damage of the liver plasma membranes and intracellular structural components of hepatocytes and endothelial cells. In experimental thyrotoxicosis, on the background of microcirculatory disorders, significant damage of plasmatic and intracellular organoid membranes of hepatocytes in the liver develops, which has an adverse effect on the functionality of the organ. The found ultrastructural changes are aggravated depending on the duration of thyrotoxicosis.

  15. 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

    2015-01-01

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

  16. Mitochondrial ultrastructure and tissue respiration of pea leaves under clinorotation

    Science.gov (United States)

    Brykov, Vasyl

    2016-07-01

    Respiration is essential for growth, maintenance, and carbon balance of all plant cells. Mitochondrial respiration in plants provides energy for biosynthesis, and its balance with photosynthesis determines the rate of plant biomass accumulation (production). Mitochondria are not only the energetic organelles in a cell but they play an essential regulatory role in many basic cellular processes. As plants adapt to real and simulated microgravity, it is very important to understand the state of mitochondria in these conditions. Disturbance of respiratory metabolism can significantly affect the productivity of plants in long-term space flights. We have established earlier that the rate of respiration in root apices of pea etiolated seedlings rose after 7 days of clinorotation. These data indicate the oxygen increased requirement by root apices under clinorotation, that confirms the necessity of sufficient substrate aeration in space greenhouses to provide normal respiratory metabolism and supply of energy for root growth. In etiolated seedlings, substrate supply of mitochondria occurs at the expense of the mobilization of cotyledon nutrients. A goal of our work was to study the ultrastructure and respiration of mitochondria in pea leaves after 12 days of clinorotation during (2 rpm/min). Plants grew at a light level of 180 μµmol m ^{-2} s ^{-1} PAR and a photoperiod of 16 h light/4 h dark. It was showed an essential increase in the mitochondrion area on 53% in palisade parenchyma cells at the sections. Such phenomenon can not be described as swelling of mitochondria, since enlarged mitochondria contained a more quantity of crista 1.76 times. In addition, the cristae total area per organelle also increased in comparison with that in control. An increase in a size of mitochondria in the experimental conditions is supposed to occur by a partial alteration of the chondriom. Thus, a size of 49% mitochondria in control was 0.1 - 0.3 μµm ^{2}, whereas only 26

  17. Ultrastructural and physiological changes induced by different stress conditions on the human parasite Trypanosoma cruzi.

    Science.gov (United States)

    Pérez-Morales, Deyanira; Hernández, Karla Daniela Rodríguez; Martínez, Ignacio; Agredano-Moreno, Lourdes Teresa; Jiménez-García, Luis Felipe; Espinoza, Bertha

    2017-01-01

    Trypanosoma cruzi is the etiological agent of Chagas disease. The life cycle of this protozoan parasite is digenetic because it alternates its different developmental forms through two hosts, a vector insect and a vertebrate host. As a result, the parasites are exposed to sudden and drastic environmental changes causing cellular stress. The stress response to some types of stress has been studied in T. cruzi, mainly at the molecular level; however, data about ultrastructure and physiological state of the cells in stress conditions are scarce or null. In this work, we analyzed the morphological, ultrastructural, and physiological changes produced on T. cruzi epimastigotes when they were exposed to acid, nutritional, heat, and oxidative stress. Clear morphological changes were observed, but the physiological conditions varied depending on the type of stress. The maintenance of the physiological state was severely affected by heat shock, acidic, nutritional, and oxidative stress. According to the surprising observed growth recovery after damage by stress alterations, different adaptations from the parasite to these harsh conditions were suggested. Particular cellular death pathways are discussed.

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

    Science.gov (United States)

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

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

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

    Directory of Open Access Journals (Sweden)

    Shadia Al-Bahlani

    2017-01-01

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

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

    Science.gov (United States)

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

    2015-09-01

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

  1. Ultrastructure of human mature oocytes after vitrification

    Directory of Open Access Journals (Sweden)

    M.A. Khalili

    2012-08-01

    Full Text Available Since the introduction of human assisted reproduction, oocyte cryopreservation has been regarded as an attractive option to capitalize the reproductive potential of surplus oocytes and preserve female fertility. However, for two decades the endeavor to store oocytes has been limited by the not yet optimized methodologies, with the consequence of poor clinical outcome or of uncertain reproducibility. Vitrification has been developed as the promising technology of cryopreservation even if slow freezing remains a suitable choice. Nevertheless, the insufficiency of clinical and correlated multidisciplinary data is still stirring controversy on the impact of this technique on oocyte integrity. Morphological studies may actually provide a great insight in this debate. Phase contrast microscopy and other light microscopy techniques, including cytochemistry, provided substantial morphofunctional data on cryopreserved oocyte, but are unable to unraveling fine structural changes. The ultrastructural damage is one of the most adverse events associated with cryopreservation, as an effect of cryo-protectant toxicity, ice crystal formation and osmotic stress. Surprisingly, transmission electron microscopy has attracted only limited attention in the field of cryopreservation. In this review, the subcellular structure of human mature oocytes following vitrification is discussed at the light of most relevant ultrastructural studies.

  2. Eccrine syringofibroadenoma (Mascaro): an ultrastructural study.

    Science.gov (United States)

    Sueki, H; Miller, S J; Dzubow, L M; Murphy, G F

    1992-06-01

    To confirm the eccrine acrosyringeal differentiation of eccrine syringofibroadenoma (ESFA) and to elucidate the histogenesis of its angiofibrotic stroma, a case of ESFA from a 45-year-old man was examined by light and electron microscopy. Histologically, the parenchyma featured anastomosing, slender epithelial cords containing small cuboidal cells and occasional duct-like structures. The stroma had increased numbers of mast cells, increased capillaries with swollen endothelial cells, and prominent fibrosis. Ultrastructurally, the following findings were characteristic of ESFA: a) abundant glycogen particles in epithelial cells, b) numerous intracytoplasmic and extracellular spaces lined with microvilli, c) intraepithelial duct formation, consisting of microvilli, vesicles, rod-shaped dense bodies, multivesicular dense bodies, and peripheral network of tonofilaments, and d) large numbers of mast cells, closely associated with fibroblasts, surrounding increased numbers of capillaries containing swollen endothelial cells. These ultrastructural features support the acrosyringeal differentiation of ESFA. We hypothesize that mast cell hyperplasia and degranulation may play an important role in the formation of the angiofibrotic stroma.

  3. Cellular dosimetry

    International Nuclear Information System (INIS)

    Humm, J.L.; Chin, L.M.

    1989-01-01

    Radiation dose is a useful predictive parameter for describing radiation toxicity in conventional radiotherapy. Traditionally, in vitro radiation biology dose-effect relations are expressed in the form of cell survival curves, a semilog plot of cell survival versus dose. However, the characteristic linear or linear quadratic survival curve shape, for high- and low-LET radiations respectively, is only strictly valid when the radiation dose is uniform across the entire target population. With an external beam of 60 Co gamma rays or x-rays, a uniform field may be readily achievable. When radionuclides are incorporated into a cell milieu, several new problems emerge which can result in a departure from uniformity in energy deposition throughout a cell population. This nonuniformity can have very important consequences for the shape of the survival curve. Cases in which perturbations of source uniformity may arise include: 1. Elemental sources may equilibrate in the cell medium with partition coefficients between the extracellular, cytosol, and nuclear compartments. The effect of preferential cell internalization or binding to cell membrane of some radionuclides can increase or decrease the slope of the survival curve. 2. Radionuclides bound to antibodies, hormones, metabolite precursors, etc., may result in a source localization pattern characteristic of the carrier agent, i.e., the sources may bind to cell surface receptors or antigens, be internalized, bind to secreted antigen concentrated around a fraction of the cell population, or become directly incorporated into the cell DNA. We propose to relate the distribution of energy deposition in cell nuclei to biological correlates of cellular inactivation. The probability of each cell's survival is weighted by its individual radiation burden, and the summation of these probabilities for the cell population can be used to predict the number or fraction of cell survivors

  4. The threat of proliferation

    International Nuclear Information System (INIS)

    Palme, Olof.

    1986-01-01

    The paper on the threat of proliferation, is a keynote speech delivered to the Colloquium on Nuclear War, Nuclear Proliferation and their Consequences, Geneva, 1985. Topics discussed in the address include: nuclear weapons, nuclear war, terrorists, Non-Proliferation Treaty, nuclear disarmament, and leadership in world affairs. (UK)

  5. Ultrastructural morphometry using dual axes tangential scale: a technical revelation.

    Science.gov (United States)

    Rayat, C S

    2005-04-01

    While performing ultrastructural morphometry, under or over estimation of ultrastructural size could be avoided by using accurate measuring devices. Biological investigators have always relied on conventional linear scale for the baseline measurement of ultrastructural size parameters on electron micrographs to project the dimensions of intracellular organelles or tissue components. Since it was not possible to measure decimal fractions of mm with linear scale, a 'dual axes tangential scale' has been designed for measuring ultrastructural image parameters on electron micrographs with an accuracy of 0.1 mm to minimize the error in finally computed size of ultrastructural component. In an exercise using 'dual axes tangential scale' and 'conventional linear scale', measurement of glomerular basement membrane thickness (GBMT) as orthogonal intercepts across the GBM revealed a 'coefficient of variation' at 4.4% with dual axes tangential scale as compared to 'coefficient of variation' at 10.9% with linear scale, expressing superiority of dual axes tangential scale over linear scale. Use of mathematical formula rather than nomogram has been preferred. However, 'slide guide, ultrastructure size calculator' could also be used for discerning ultrastructural size after measurement with dual axes tangential scale.

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

    Directory of Open Access Journals (Sweden)

    Succar L

    2016-11-01

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

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

    Directory of Open Access Journals (Sweden)

    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

  8. 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.

  9. 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

  10. Ultrastructure of epidermis of Salamandra salamandra followed throughout ontogenesis.

    Science.gov (United States)

    Warburg, M R; Lewinson, D

    1977-07-15

    Ventral epidermal ultrastructure of the amphibian urodele Salamandra salamandra is described and followed throughout its life cycle. Tadpoles were divided into five categories on the basis of the organization of their epidermis and the ultrastructure of its cells. In newly hatched tadpoles the epidermis is arranged in two layers and four types of cells were recognized. The number of epidermal layers increases in the metamorphosing tadpole. At this stage the layers become organized in four strata. Metamorphosis involves the disappearance of some cell types and the appearance of others, typical of the adult epidermis. The significance of these ontogenetic changes in epidermal ultrastructure is discussed in respect to aquatic and terrestrial life habits.

  11. Fissile material proliferation risk

    International Nuclear Information System (INIS)

    Dreicer, J.S.; Rutherford, D.A.

    1996-01-01

    The proliferation risk of a facility depends on the material attractiveness, level of safeguards, and physical protection applied to the material in conjunction with an assessment of the impact of the socioeconomic circumstances and threat environment. Proliferation risk is a complementary extension of proliferation resistance. The authors believe a better determination of nuclear proliferation can be achieved by establishing the proliferation risk for facilities that contain nuclear material. Developing a method that incorporates the socioeconomic circumstances and threat environment inherent to each country enables a global proliferation assessment. To effectively reduce the nuclear danger, a broadly based set of criteria is needed that provides the capability to relatively assess a wide range of nuclear related sites and facilities in different countries and still ensure a global decrease in proliferation risk for fissile material (plutonium and highly enriched uranium)

  12. Successive interference cancellation in uplink cellular networks

    NARCIS (Netherlands)

    Wildemeersch, Matthias; Wildemeersch, Matthias; Quek, Tony Q.S.; Kountouris, Marios; Slump, Cornelis H.

    2013-01-01

    In recent years, operators addressed the explosive growth of mobile data demand by densifying the cellular network so as to achieve a higher spectral efficiency and increase their capacity. The intense proliferation of wireless devices resulted in interference limited networks, which suggests the

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

    Directory of Open Access Journals (Sweden)

    S. A. Sakr

    2014-01-01

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

  14. Ultrastructural evidence that ependymal cells are infected in experimental scrapie.

    Science.gov (United States)

    Fournier, Jean-Guy; Adjou, Karim; Grigoriev, Vladimir; Deslys, Jean-Philippe

    2008-06-01

    During the last stage of infection in the experimental scrapie-infected hamster model, light microscopy reveals typical immunostaining of PrPsc in the subependymal region and at the apical ependymal cell borders. Whereas the subependymal immuno-staining is known to originate from extracellular amyloid filaments and residual membranes of astrocytes as constituents of plaque-like structures, the ultrastructural correlate of the supraependymal PrPsc staining remains uncertain. To decipher this apical PrPsc immunopositivity and subsequently the ependymocyte-scrapie agent interaction, we employed highly sensitive immuno-electron microscopy for detecting PrPsc in 263K scrapie-infected hamster brains. The results revealed the supraependymal PrPsc signal to be correlated not only with extracellular accumulation of amyloid filaments, but also with three distinct ependymal cell structures: (1) morphologically intact or altered microvilli associated with filaments, (2) the ependymal cell cytoplasm in proximity of apical cell membrane, and (3) intracytoplasmic organelles such as endosomes and lysosomal-like structures. These findings suggest a strong ependymotrope feature of the scrapie agent and recapitulate several aspects of the cell-prion interaction leading to the formation and production of PrPsc amyloid filaments. Our data demonstrate that in addition to neurons and astrocytes, ependymocytes constitute a new cellular target for the scrapie agent. In contrast, the absence of PrPsc labeling in choroid plexus and brain vascular endothelial cells indicates that these cells are not susceptible to the infection and may inhibit passage of the infectious agent across the blood-brain barrier.

  15. Effect of c-myc on the ultrastructural structure of cochleae in guinea pigs with noise induced hearing loss

    Energy Technology Data Exchange (ETDEWEB)

    Han, Yu; Zhong, Cuiping [Department of Otolaryngology, Xijing Hospital, Fourth Military Medical University, Xi' an, 710032 Shaanxi Province (China); Hong, Liu [First Division of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi' an, 710032 Shaanxi Province (China); Wang, Ye; Qiao, Li [Department of Otolaryngology, Xijing Hospital, Fourth Military Medical University, Xi' an, 710032 Shaanxi Province (China); Qiu, Jianhua, E-mail: qiujh@fmmu.edu.cn [Department of Otolaryngology, Xijing Hospital, Fourth Military Medical University, Xi' an, 710032 Shaanxi Province (China)

    2009-12-18

    Noise over-stimulation may induce hair cells loss and hearing deficit. The c-myc oncogene is a major regulator for cell proliferation, growth, and apoptosis. However, the role of this gene in the mammalian cochlea is still unclear. The study was designed to firstly investigate its function under noise condition, from the aspect of cochlear ultrastructural changes. We had established the adenoviral vector of c-myc gene and delivered the adenovirus suspension into the scala tympani of guinea pigs 4 days before noise exposure. The empty adenoviral vectors were injected as control. Then, all subjects were exposed to 4-kHz octave-band noise at 110 dB SPL for 8 h/day, 3 days consecutively. Auditory thresholds were assessed by auditory brainstem response, prior to and 7 days following noise exposure. On the seventh days after noise exposure, the cochlear sensory epithelia surface was observed microscopically and the cochleae were taken to study the ultrastructural changes. The results indicated that auditory threshold shift after noise exposure was higher in the ears treated with Ad.EGFP than that treated with Ad.c-myc-EGFP. Stereocilia loss and the disarrangement of outer hair cells were observed, with greater changes found in the Ad.EGFP group. Also, the ultrastructure changes were severe in the Ad.EGFP group, but not obvious in the Ad.c-myc-EGFP group. Therefore, c-myc gene might play an unexpected role in hearing functional and morphological protection from acoustic trauma.

  16. Cellular proliferation and regeneration following tissue damage. Progress report. [Eyes

    Energy Technology Data Exchange (ETDEWEB)

    Harding, C.V.

    1976-10-01

    Results are reported from a study of wound healing in tissues of the eye, particularly lens, cornea, and surrounding tissues. The reactions of these tissues to mechanical injuries, as well as injuries induced by chemotoxic agents were studied. It is postulated that a better understanding of the basic reactions of the eye to injurious agents may be of importance in the evaluation of potential environmental hazards.

  17. Amine functionalized nanodiamond promotes cellular adhesion, proliferation and neurite outgrowth

    International Nuclear Information System (INIS)

    Hopper, A P; Dugan, J M; Gill, A A; Haycock, J W; Claeyssens, F; Fox, O J L; May, P W

    2014-01-01

    In this study, we report the production of amine functionalized nanodiamond. The amine functionalized nanodiamond forms a conformal monolayer on a negatively charged surface produced via plasma polymerization of acrylic acid. Nanodiamond terminated surfaces were studied as substrates for neuronal cell culture. NG108-15 neuroblastoma-glyoma hybrid cells were successfully cultured upon amine functionalized nanodiamond coated surfaces for between 1 and 7 d. Additionally, primary dorsal root ganglion (DRG) neurons and Schwann cells isolated from Wistar rats were also successfully cultured over a period of 21 d illustrating the potential of the coating for applications in the treatment of peripheral nerve injury. (paper)

  18. Ultrastructure of spermatogenesis, spermatozoon and processes of testicular regression and recrudescence in Eptesicus furinalis (Chiroptera: Vespertilionidae).

    Science.gov (United States)

    Bueno, Larissa M; Beguelini, Mateus R; Comelis, Manuela T; Taboga, Sebastião R; Morielle-Versute, Eliana

    2014-08-01

    Studies have shown that the annual reproductive cycle of Eptesicus furinalis includes at least one period of total testicular regression. Thus, this study aimed to evaluate their reproductive cycle ultrastructurally. The annual reproductive cycle was divided into four periods: active, regressing, regressed and recrudescence. The active period was similar to that of other bats, including the completion of spermatogenesis with three main types of spermatogonia (Ad, Ap and B) and 12 steps in the process of spermatid differentiation. However, its spermatozoa differed in that outer dense fibers 1, 5, 6 and 9 are larger than the others and due to the presence of what is likely a probably genera-specific bulging in the anterior portion. In the regressing period, Sertoli cell nuclei migrate to the basal compartment with the nuclei close to the basal lamina. The basal compartment had a more compact appearance than the adluminal compartment, with relaxed cellular connections. In the regressed period, spermatogenesis ceased; the seminiferous epithelium was composed only of Sertoli cells and three types of spermatogonia: types Ad, 1 and 2. In the recrudescence period, spermatogenesis restarted, with the process of reactivation divided into three phases: early, medial and late recrudescence. In conclusion, our study described the process of spermatogenesis and the ultrastructure of the spermatozoa and confirmed the presence of a process of total testicular regression in the annual cycle of E. furinalis. We characterize distinct morphologic variations in the ultrastructure of the testicular cells during the four different periods of the annual reproductive cycle. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Ultrastructure: effects of melanin pigment on target specificity using a pulsed dye laser (577 nm)

    Energy Technology Data Exchange (ETDEWEB)

    Tong, A.K.; Tan, O.T.; Boll, J.; Parrish, J.A.; Murphy, G.F.

    1987-06-01

    It has been shown recently that brief pulses of 577 nm radiation from the tunable dye laser are absorbed selectively by oxyhemoglobin. This absorption is associated with highly specific damage to superficial vascular plexus blood vessels in those with lightly pigmented (type I-II) skin. To determine whether pigmentary differences in the overlying epidermis influence this target specificity, we exposed both type I (fair) and type V (dark) normal human skin to varying radiant exposure doses over 1.5-microsecond pulse durations from the tunable dye laser at a wavelength of 577 nm. Using ultrastructural techniques, we found in type I skin that even clinical subthreshold laser exposures caused reproducible alterations of erythrocytes and adjacent dermal vascular endothelium without comparable damage to the overlying epidermis. In contrast, degenerated epidermal basal cells represented the predominant form of cellular damage after laser exposure of type V skin at comparable doses. We conclude that epidermal melanin and vascular hemoglobin are competing sites for 577 nm laser absorption and damage, and that the target specificity of the 577 nm tunable dye laser is therefore influenced by variations in epidermal pigmentation. This finding is relevant to the clinical application of the tunable dye laser in the ablative treatment of vascular lesions. We also found on ultrastructure that the presence of electron-lucent circular structures of approximately 800 A in diameter were observed only at and above clinical threshold doses in those with type I skin and at the highest dose of 2.75 J/cm2 in type V skin. It has been proposed that these structures might be heat-fixed molds of water vapor. Both this and ultrastructural changes of epidermal basal cells demonstrate mechanisms responsible for alteration of tissue after exposure to 577 nm, which are discussed.

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

    Science.gov (United States)

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

    2006-01-01

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

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

    Science.gov (United States)

    Paul, Mayura; Shetty, Devi Charan

    2013-01-01

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

  2. 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.

  3. Ação inibitória da Interleucina - 1ß sobre a proliferação de células musculares lisas cultivadas a partir de veias safenas humanas Inhibitory action of the Interleukin 1ß over the cellular proliferation of smooth muscle cells cultivated from human saphenous veins

    Directory of Open Access Journals (Sweden)

    Luís A.O. Dallan

    2005-06-01

    conditions (AHC. The Interleukin - 1ß expression was also elevated in these veins slices. The aim of this study is to evaluate the influence of the interleukin - 1ß in the precocious proliferation of the cultures of primary smooth muscle cells (PSMC. METHOD: PSMC of six different human SVs were cultivated in Dulbecco's Modified Eagle Method associated with bovine fetal serum. The control group was not treated with Interleukin - 1ß but treated groups were. Cellular proliferation (CP was evaluated by measuring triple thymidine [³H], incorporated into the proliferated cells. RESULTS: The treatment with Interleukin - 1ß decreases cellular proliferation. The control group presented 100 ± 4.5% of CP. In the treated groups the quantity of Interleukin - 1ß administered and the respective levels of CP observed were: 0.1 ng/ml - 112 ± 0.7%; 1 ng/mL - 83 ± 4.7%; 10 ng/mL - 69.1 ± 3.8% and 100 ng/mL - 76.3 ± 10.9% (p < 0.01. CONCLUSION: We can conclude that the administration of increasing quantities of Interleukin - 1ß inhibits the proliferation of PSMC cultivated from human SVs. This suggests that the precocious process of apoptosis observed in the SV grafts exposed to AHC can be related to the action of this interleukin.

  4. [Primary synovial sarcoma of the mediastinum. A case report with immunohistochemistry, ultrastructural and cytogenetic study].

    Science.gov (United States)

    Peoc'h, M; Le Marc'hardour, F; Bost, F; Pasquier, D; Roux, J J; Pinel, N; Leroux, D; Pasquier, B

    1995-01-01

    A biphasic synovial sarcoma occurring in the anterior and inferior mediastinum in a 19-year-old woman is reported. A biopsy showed a mesenchymal proliferation and the tumor was first misdiagnosed as a hemangiopericytoma. Inefficacy of chemotherapy led to a tumorectomy. Histologic and immunohistochemical studies on multiple samples showed a biphasic tumor. Ultrastructural study confirmed the presence of epithelial elements and cytogenetic analysis disclosed a translocation t(X;18) (p11;q11), leading to a diagnosis of synovial sarcoma. Synovial sarcoma of the mediastinum is very rare and to our knowledge has not been previously studied with the help of cytogenetics. Given the biphasic pattern of the tumor and its mediastinal location, it can be confused with mesothelioma. This stresses the interest of chromosome analysis in the study of tumors histologically difficult to classify.

  5. France and nuclear proliferation

    International Nuclear Information System (INIS)

    Barrillot, B.

    2001-05-01

    The Observatory of French nuclear weapons looks forwards to the elimination of nuclear weapons in conformity with the aims of the nuclear non-proliferation Treaty. This file tackles the breakdown of disarmament, the missile-launching nuclear submarines ( new generation) program counter to non-proliferation, nuclear submarines, security and health, nuclear submarines and the environment, the program itself and the requirements of the non proliferation treaty. (N.C.)

  6. Globalization and Proliferation

    Science.gov (United States)

    2005-08-01

    growing with each other? Is the process of globalization as it makes technology , education, etc., available to more and more coun- tries—and even...So to conclude, I ask, does globalization make the world go to hell because of rampant proliferation of technology , falling into the 23. And their...CIM D0012837.A1/Final August 2005 Globalization and Proliferation A presentation to a Workshop on Proliferation Networks at the Naval

  7. Proliferation: myth or reality?

    International Nuclear Information System (INIS)

    2005-01-01

    This article analyzes the proliferation approach, its technical condition and political motivation, and the share between the myth (political deception, assumptions and extrapolations) and the reality of proliferation. Its appreciation is complicated by the irrational behaviour of some political actors and by the significant loss of the non-use taboo. The control of technologies is an important element for proliferation slowing down but an efficient and autonomous intelligence system remains indispensable. (J.S.)

  8. Ultrastructural Changes and Bacterial Localization in Buffalo Calves Following Oral Exposure to Pasteurella multocida B:2

    Directory of Open Access Journals (Sweden)

    M.S. Abubakar, M. Zamri-Saad* and S. Jasni

    2013-01-01

    Full Text Available This study describes the ultrastructural changes and distribution of P. multocida B:2 in the respiratory and gastrointestinal tracts of buffalo calves following oral exposure and compared with intratracheal exposure. Nine 8-month old buffalo calves were divided into 3 groups. At the start of the experiment, dexamethasone (1mg/kg was injected intramuscularly into buffaloes of all groups for three consecutive days. Then, calves of Group 1 were exposed orally to 50ml of the inoculum containing 109 colony-forming unit (CFU/mL of live P. multocida B:2. Calves of Group 2 were exposed intra-tracheal to the same inoculum while calves of Group 3 were exposed orally to PBS. Transient and mild clinical signs were observed in calves of Groups 1 and 2. Pasteurella multocida B:2 was isolated from the nasal mucosa for up to 5 days post-infection. Only calf that was killed at 48 h post-infection had P. multocida B:2 in both respiratory and gastro-intestinal tracts showing ultrastructural changes typical of acute cellular injury, with degeneration of endothelium and vascular walls. There were deciliation in the respiratory and microvilli degeneration in the gastrointestinal tracts. The study concludes that oral exposure may not play major role in the development of hemorrhagic septicemia. Nevertheless, the buffalo calf that succumbed to hemorrhagic septicemia carried P. multocida B:2 in the gastro-intestinal organs.

  9. Fate and ultra-structural features of chicken skin mucosa around juvenile polyps.

    Science.gov (United States)

    El-Hodhod, M A; Soliman, A A; Hamdy, A M; Abdel-Rahim, A A; Abdel-Hamid, F K

    2011-03-01

    Chicken skin mucosa (CSM) is a common finding around juvenile polyps in children. Its ultrastructural features and fate after polypectomy are not yet clear. The aim was to study ultra-structural features and outcome of this CSM compared to that of the polyps and distant endoscopically normal mucosa. From 240 children with juvenile polyps, 45 needed a second colonoscopy. Thirty six patients showing CSM represented the cohort of this study. One polyp only was studied in each patient. The histologic features of the CSM were compared to normal and polyp mucosa. The fate of CSM was evaluated in the second colonoscopy. The mean numbers of intraepithelial lymphocytes, as well as lamina propria inflammatory cellular infiltrates were significantly higher in polyp mucosa than in CSM. Goblet cells were significantly higher in CSM compared to normal mucosa with marked depletion in the polyp mucosa. The muscularis mucosae thickness was significantly higher in CSM compared to polyps (ppolyp showed the most intense mucosal inflammatory reaction. CSM with the unique thickening of muscularis mucosae especially around larger polyps almost disappeared after polypectomy. So these results suggest that CSM is a benign compensatory reaction induced by the mechanical effect of the polyp.

  10. 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)

  11. Induction and Morpho-Ultrastructural Analysis of Organogenic Calli of a Wild Passionfruit

    Directory of Open Access Journals (Sweden)

    Milene Alves de Figueiredo Carvalho

    2014-12-01

    Full Text Available This work studied a new protocol for organogenic calli induction and characterization of the morphology and ultrastructure of callogenesis in leaf explants of Passiflora gibertii N. E. Brown, a native passion fruit species from Brazil. Calli induction was performed in different growth conditions (light and dark, different MS medium salt concentrations (MS and MS half strength and the presence or absence of coconut water. The leaf explants maintained in the dark were more responsive to bud formation. In order to reduce spending on in vitro culture, the most suitable induction medium for P. gibertii organogenesis could, therefore be the MS half strength salt concentration medium maintained in the dark. The addition of coconut water to the culture medium was essential for both calli induction and bud formation. The morphological and ultrastructural features of the organogenic calli were isodiametric cells, characterized by an organized cellular system, nucleus with prominent nucleoli, presence of starch grains and dense cytoplasm rich in endoplasmic reticulum. The scanning electron microscopy demonstrated that buds were present on these calli.

  12. New Portland cement-based materials for endodontics mixed with articaine solution: a study of cellular response.

    Science.gov (United States)

    Gandolfi, Maria Giovanna; Perut, Francesca; Ciapetti, Gabriela; Mongiorgi, Romano; Prati, Carlo

    2008-01-01

    The biocompatibility of innovative tetrasilicate cements proposed for root-end filling restorations was tested. White ProRoot-MTA and AH Plus were used as control. The new cements were mixed with a local anesthetic solution (4% articaine) to form a paste. Human osteoblast-like cells Saos-2 were challenged in short-term cultures (72 hours) with solid materials and with material extracts prepared in culture medium. Cell growth and viability, cellular attachment, and morphologic features were assessed to verify cell/material interactions. No acute toxicity was exerted by the experimental cements in the assay systems. On solid samples Saos-2 adhered and proliferated on all the experimental cements and on MTA. The ultrastructural findings revealed that Saos-2 were able to adhere and to spread. The maintenance of the osteoblastic phenotype on the innovative cements was confirmed by the alkaline phosphatase assay. All experimental cements prepared with articaine supported the growth of bone-like cells, showing suitable properties to be used as canal sealers and root-end filling materials.

  13. Director's series on proliferation

    International Nuclear Information System (INIS)

    Bailey, K.C.; Price, M.E.

    1995-01-01

    This is an occasional publication of essays on the topics of nuclear, chemical, biological, and missile proliferation. The views represented are those of the author's. Essay topics include: Nuclear Proliferation: Myth and Reality; Problems of Enforcing Compliance with Arms Control Agreements; The Unreliability of the Russian Officer Corps: Reluctant Domestic Warriors; and Russia's Nuclear Legacy

  14. More histologic and ultrastructural degenerative signs in the subscapularis tendon and the joint capsule in male patients with shoulder impingement.

    Science.gov (United States)

    Farfaras, Stefanos; Ejerhed, Lars Erik; Hallström, Erling K; Hultenby, Kjell; Meknas, Khaled; Movin, Tomas; Papadogiannakis, Nikos; Kartus, Jüri-Toomas

    2018-01-01

    The purpose of the present study was to analyze biopsy samples from the subscapularis tendon and from the joint capsule from male patients with shoulder impingement syndrome (SAIS) and compare them with samples from male patients with post-traumatic recurrent shoulder instability. The hypothesis of the study was that patients with SAIS would have more histologic and ultrastructural degenerative changes in their subscapularis tendon and joint capsule than patients with post-traumatic recurrent shoulder instability. Male patients scheduled for surgery, with either subacromial decompression or Bankart reconstruction, were included. Four biopsies from each patient were obtained from the capsule and four from the subscapularis tendon during arthroscopic surgery. The histologic characteristics and the presence of glycosaminoglycans were assessed using the light microscope, and the ultrastructure was assessed using a transmission electron microscope. Eight patients, median age 53 (45-74) years (p impingement group, and 12 patients, median age 27 (22-48) years, were included in the instability group. The histologic assessment revealed significantly higher cellularity and total degeneration score in the capsule (p = 0.016 and p = 0.014 respectively) in patients with subacromial impingement compared with the instability patients. The corresponding finding was not made for the subscapularis tendon. The ultrastructural evaluation revealed that the instability patients had more fibrils with a large diameter (indicating less degeneration) in both the subscapularis tendon and the capsule compared with the impingement patients (p impingement have more histologic and ultrastructural degenerative changes in their shoulder compared with patients with post-traumatic recurrent shoulder instability. It appears that in patients with subacromial impingement, the whole shoulder joint is affected and not only the subacromial space. It is the opinion of the authors that intra

  15. Proliferation Networks and Financing

    International Nuclear Information System (INIS)

    Gruselle, Bruno

    2007-01-01

    The objective of this study is to propose practical solutions aimed at completing and strengthening the existing arrangement for the control of nuclear proliferation through a control of financial as well as material or immaterial flows. In a first part, the author proposes a systemic analysis of networks of suppliers and demanders. He notably evokes the Khan's network and the Iraqi acquisition network during the 1993-2001 period. He also proposes a modelling of proliferation networks (supplier networks and acquisition networks) and of their interactions. In a second part, the author examines possible means and policies aimed at neutralising proliferation networks: organisation, adaptation and improvement of intelligence tools in front of proliferation networks, and means, limitations and perspectives of network neutralisation. He also briefly addresses the possibility of military action to contain proliferation flows

  16. Enamel ultrastructure in pigmented hypomaturation amelogenesis imperfecta.

    Science.gov (United States)

    Wright, J T; Lord, V; Robinson, C; Shore, R

    1992-10-01

    Hypomaturation amelogenesis imperfecta (AI) is a hereditary condition of enamel that is presumed to result from defects during the maturation stage of enamel development. This study characterized the enamel ultrastructure and enamel crystallite morphology, as well as the distribution of organic material in enamel affected with pigmented hypomaturation AI. Enamel exhibiting autosomal recessive pigmented hypomaturation AI was sectioned or fractured and examined using light microscopy, scanning electron microscopy and transmission electron microscopy. Enamel samples were treated with 30% NaOCl or 8 M urea to remove organic components and determine the effect of deproteinization on crystallite morphology. These were compared with untreated normal enamel samples. The enamel crystallites in hypomaturation AI exhibited considerable variability in size and morphology. Examination of deproteinized tissue indicated that the AI crystallites had a thick coating, presumably of organic or partially mineralized material, which was not visible in normal enamel. The results of this investigation provide further evidence that hypomaturation AI is associated with the retention of organic material that is most probably enamel protein. Enamel protein retention is likely to be involved in the inhibition of normal crystallite growth resulting in the morphological crystallite abnormalities associated with this disorder.

  17. Spermatozoon ultrastructure in two monorchiid digeneans.

    Science.gov (United States)

    Quilichini, Yann; Bakhoum, Abdoulaye J S; Justine, Jean-Lou; Bray, Rodney A; Bâ, Cheikh T; Marchand, Bernard

    2016-01-01

    Spermatological characteristics of species from two monorchiid genera, Opisthomonorchis and Paramonorcheides, have been investigated, for the first time, by means of transmission electron microscopy. The ultrastructural study reveals that the mature spermatozoon of Opisthomonorchis dinema and Paramonorcheides selaris share several characters such as the presence of two axonemes of different lengths showing the 9+"1" pattern of the Trepaxonemata, a nucleus, two mitochondria, two bundles of parallel cortical microtubules, external ornamentation of the plasma membrane, spine-like bodies, granules of glycogen and similar morphologies of the anterior and posterior extremities. The slight differences between the male gamete of O. dinema and P. selaris are the length of the first axoneme and the position of the second mitochondrion. This study also elucidates the general morphology of the spermatozoon in all monorchiid species described so far, which corresponds to a unique spermatozoon type. Other interesting finds concern the spermatological similarities between monorchiid spermatozoa and the mature spermatozoon reported in the apocreadiid Neoapocreadium chabaudi. These similarities allow us to suggest a close phylogenetical relationship between the Monorchiidae and the Apocreadiidae, although more studies are needed, especially in the unexplored taxa.

  18. Ultrastructural cytochemical analysis of intranuclear arsenic inclusions

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, E.M.B.

    1987-01-01

    To establish the chemical composition of the arsenic inclusion, freshly isolated preparations of inclusions and epon-embedded thin sections of inclusions were subjected to ultrastructural cytochemical analysis. Intranuclear inclusions are composed of amorphous, arsenic-containing subunits aligned linearly to form a coiled complex. Lipase, ribonuclease, deoxyribonuclease, trypsin, pepsin, protease, amylase, or ethylenediaminetetraacetic acid (EDTA) was used to digest or chelate these inclusions. Following enzymatic digestion or chelation, the electron opacity of inclusions was compared with that of control sections exposed for equal times to equivalent solutions lacking the enzymes. Exposure to amylase caused a consistent reduction in the electron opacity of thin sections of inclusions and almost complete digestion of the freshly isolated preparations of inclusions. This was indicative of the presence of a carbohydrate moiety within arsenic inclusions. Incubation of inclusions with EDTA resulted in solubilization of freshly isolated and thin-sectioned embedded material. These data indicated that the intranuclear arsenic inclusion is composed of both metallic and carbohydrate moieties, confirming earlier studies which identified arsenic within inclusions using instrumental neutron activation analysis and x-ray microprobe analysis.

  19. Ultrastructural Characterization of Zika Virus Replication Factories.

    Science.gov (United States)

    Cortese, Mirko; Goellner, Sarah; Acosta, Eliana Gisela; Neufeldt, Christopher John; Oleksiuk, Olga; Lampe, Marko; Haselmann, Uta; Funaya, Charlotta; Schieber, Nicole; Ronchi, Paolo; Schorb, Martin; Pruunsild, Priit; Schwab, Yannick; Chatel-Chaix, Laurent; Ruggieri, Alessia; Bartenschlager, Ralf

    2017-02-28

    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. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  20. Spermatozoon ultrastructure in two monorchiid digeneans

    Directory of Open Access Journals (Sweden)

    Yann Quilichini

    2016-09-01

    Full Text Available Spermatological characteristics of species from two monorchiid genera, Opisthomonorchis and Paramonorcheides, have been investigated, for the first time, by means of transmission electron microscopy. The ultrastructural study reveals that the mature spermatozoon of Opisthomonorchis dinema and Paramonorcheides selaris share several characters such as the presence of two axonemes of different lengths showing the 9+“1” pattern of the Trepaxonemata, a nucleus, two mitochondria, two bundles of parallel cortical microtubules, external ornamentation of the plasma membrane, spine-like bodies, granules of glycogen and similar morphologies of the anterior and posterior extremities. The slight differences between the male gamete of O. dinema and P. selaris are the length of the first axoneme and the position of the second mitochondrion. This study also elucidates the general morphology of the spermatozoon in all monorchiid species described so far, which corresponds to a unique spermatozoon type. Other interesting finds concern the spermatological similarities between monorchiid spermatozoa and the mature spermatozoon reported in the apocreadiid Neoapocreadium chabaudi. These similarities allow us to suggest a close phylogenetical relationship between the Monorchiidae and the Apocreadiidae, although more studies are needed, especially in the unexplored taxa.

  1. The secondary tongue of Salamandra salamandra: histochemical and ultrastructural aspects of the developing lingual epithelium.

    Science.gov (United States)

    Opolka, A; Wistuba, J; Clemen, G

    2001-01-01

    The development of the lingual epithelium of Salamandra salamandra was investigated with emphasis on histochemical and ultrastructural aspects. The temporal and spatial occurrence and the typical appearance of various cell types; i.e. pavement cells, replacement pavement cells, basal cells, mitochondria rich cells, goblet cells and glandular cells have been analysed and documented in detail from the young larval stage up to the metamorphosed animal (2 months after metamorphosis). It is shown that anatomical re- and de novo-constructions related to the formation of the secretory tongue led to distinct changes in the cellular equipment of the epithelium of the tongue, including various histochemical properties. Finally, functional aspects of the morphological characteristics are discussed in detail and compared with respective findings in other species.

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

    Directory of Open Access Journals (Sweden)

    Juan P. Hernández-Fonseca

    2009-01-01

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

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

    Science.gov (United States)

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

    2011-01-01

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

  4. The venom gland of the scorpion species Euscorpius mingrelicus (Scorpiones: Euscorpiidae: morphological and ultrastructural characterization

    Directory of Open Access Journals (Sweden)

    N Yigit

    2008-01-01

    Full Text Available The histology and ultrastructure of venom glands in the scorpion Euscorpius mingrelicus (Kessler, 1874 are described and illustrated in the current study for the first time by employing light microscopy and transmission electron microscopy (TEM. The venom apparatus is composed of a pair of venom glands and a stinger, both situated in the last segment of the metasoma. The venom glands are completely separate but similar. The two glands are segregated within the telson by striated muscle bundles, and their outer surfaces are surrounded by a cuticle. An internal layer constitutes the secretory epithelium. This epithelium is made up of simple columnar cells. The nucleus and organelles involved in cellular synthetic activity are situated basally. In the apical portion, near the gland lumen, there are many secretory granules of different sizes, shapes and electron densities.

  5. Ultrastructure of the corpus cardiacum and corpus allatum of the house cricket Acheta domesticus.

    Science.gov (United States)

    Bradley, J T; Edwards, J S

    1979-05-18

    The ultrastructure of the corpus cardiacum (CC) and corpus allatum (CA) of the house cricket, Acheta domesticus, is described. Axon profiles within the CC contain neurosecretory granules 160-350 nm in diameter which are indistinguishable from those found in type I neurosecretory cells of the pars intercerebralis and in the nervus corporis cardiaci I. The CC itself contains two cell types: intrinsic neurosecretory cells and glial cells. Intrinsic NSC cytoplasm contains Golgi bodies and electron dense neurosecretory granules 160-350 nm in diameter. Synaptoid configurations with 20-50 nm diameter electron lucent vesicles were observed within axon profiles of the CC. The structure of the CA is relatively uniform with one cell type predominating. Typical CA cells possess large nucleoli, active Golgi complexes, numerous mitochondria, and occassional microtubules. Groups of dark staining cells scattered throughout the CA of some animals were interpreted as evidence of cellular death.

  6. Cellular: Toward personal communications

    Science.gov (United States)

    Heffernan, Stuart

    1991-09-01

    The cellular industry is one of the fastest growing segment of the telecommunications industry. With an estimated penetration rate of 20 percent in the near future, cellular is becoming an ubiquitous telecommunications service in the U.S. In this paper we will examine the major advancements in the cellular industry: customer equipment, cellular networks, engineering tools, customer support, and nationwide seamless service.

  7. An ultrastructural and a cytochemical study of candidal invasion of reconstituted human oral epithelium.

    Science.gov (United States)

    Jayatilake, J A M S; Samaranayake, Y H; Samaranayake, L P

    2005-04-01

    Opportunistic yeast, Candida albicans causes superficial and systemic mycoses in compromised patients. Adhesion to host tissues, morphogenesis and extracellular phospholipases (PL) are thought to contribute to its virulence. The nature of numerous host-parasite interactions at the invasive phase of oral candidiasis is not fully understood. Hence in this study, we explore the ultrastructural features of oral candidiasis using a tissue culture model based on reconstituted human oral epithelium (RHOE). Reconstituted human oral epithelium (Skinethic Laboratory, Nice, France) was inoculated with C. albicans SC5314 and incubated up to 48 h. The infected tissue was harvested at 12, 24 and 48 h and examined using light, scanning (SEM) and transmission electron microscopy (TEM). Localized activity of PLs of C. albicans during tissue invasion was also examined using a cytochemical method. Over a period of 48 h C. albicans invaded the RHOE, and histological examination revealed characteristic hallmarks of pathological tissue invasion. Hyphal penetration into the superficial epithelium, particularly at cell junctions, together with features of cellular internalization of yeasts was noted. Phospholipase activity was visible at the tips of hyphae and initial sites of bud formation. Further, SEM studies revealed cavitations on the surface epithelial cells particularly pronounced at the sites of hyphal invasion. Hyphal invasion was seen both at cell surfaces and intercellular cell junctions of the epithelium, the latter resembling thigmotropic behaviour. Our findings confirm that multiple cellular interactions such as internalization, thigmotropism and extracellular PLs contribute to invasive candidiasis. The RHOE model, described here, appears to be a satisfactory model for the investigation of ultrastructural and histochemical features of invasive candidiasis in humans.

  8. Ultrastructural studies of time-course and cellular specificity of interleukin-1 mediated islet cytotoxicity

    DEFF Research Database (Denmark)

    Mandrup-Poulsen, T; Egeberg, J; Nerup, J

    1987-01-01

    of incubation and examined by electron microscopy in a blinded fashion. Already after 30 min, accumulation of opaque intracytoplasmic bodies without apparent surrounding membranes, and autophagic vacuoles were seen in about 20% of the beta cells examined in rat islets exposed to interleukin-1. After 16 h...

  9. Non-proliferation

    International Nuclear Information System (INIS)

    Manley, I.T.

    1981-01-01

    Proliferation is a problem that can only be solved when the political problems which lead countries to contemplate, the possession of nuclear weapons are solved; in the meantime it can only be managed. Non-proliferation policy has to deal both with the political and the technical aspects of proliferation. It must seek to buy time by addressing the reasons why nations feel the political need to construct nuclear weapons, as well as delaying the moment when such nations feel capable of doing so. The subject is examined and proposals made. (author)

  10. Getting serious about proliferation

    International Nuclear Information System (INIS)

    Leventhal, P.

    1984-01-01

    The US needs to give a higher priority to nuclear non-proliferation, but Reagan's policies assume that proliferation is inevitable and that it is more important to be a reliable supplier than to cause trade frictions by trading only with those nations which sign the non-proliferation treaty (NPT). This undercuts US leadership and the intent of the agreement. Several bills now before Congress could help to restore US leadership by tightening export restrictions and the use of plutonium from the US

  11. Cruise Missile Proliferation

    National Research Council Canada - National Science Library

    Feickert, Andrew

    2005-01-01

    About 75 countries currently possess cruise missiles.1 Many experts predict that anti- ship and land attack cruise missile proliferation will increase in terms of both scope and technological sophistication...

  12. Countering Chinese Proliferation Activity

    National Research Council Canada - National Science Library

    Tomchik, Stephen J

    1994-01-01

    Control of the proliferation of nuclear technology (including fissile material), chemical and biological weapons and their precursors, and ballistic missile delivery systems continues to be a priority for the United States Government...

  13. The ultrastructure of separated and cultured cell of Porphyra yezoensis

    Science.gov (United States)

    Mei, Jun-Xue; Fei, Xiu-Geng

    2001-03-01

    There are many reports that cells (protoplasts) separated from the thallus of Porphyra by enzyme can develop to normal leafy thalli in the same way as monospores. But there are few investigations on the subcellular structure of the isolated vegetative cell for comparison with the subcellular structure of monospores. To clarify whether the separated and cultured cells undergo the same or similar ultrastructure changes during culture and germination as monospores undergo in their formation and germination, we observed their ultrastructure, compared them with those of the monospore and found that the ultrastructure of separated and cultured cells did not have the characteristic feature as that of monospore formation, such as production of small and large fibrous vesicles, but was accompanied by vacuolation and starch mobilization like that in monospore germination. The paper also discusses the relations between monospores and separated and cultured cells.

  14. Early studies of placental ultrastructure by electron microscopy

    DEFF Research Database (Denmark)

    Carter, A M; Enders, A C

    2016-01-01

    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...... 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...

  15. 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

  16. Enhancing Therapeutic Cellular Prostate Cancer Vaccines

    Science.gov (United States)

    2012-06-01

    a cystatin -like molecule, inhibits ERK-dependent lymphocyte proliferation. Mech Ageing Dev 126:1284-91 7. Gomez, C.R., Acuña-Castillo, C ., Nishimura...the development of better prostate cancer cell vaccines 2. Gomez, C.R., Kosari, F., Munz, J.M., Schreiber, C ., Knutson, G., Charlesworth, C ., Karnes...TITLE: Enhancing Therapeutic Cellular Prostate Cancer Vaccines PRINCIPAL INVESTIGATOR: Christian R. Gomez, Ph.D

  17. Scaffold architecture and fibrin gels promote meniscal cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Pawelec, K. M., E-mail: pawelec.km@gmail.com, E-mail: jw626@cam.ac.uk; Best, S. M.; Cameron, R. E. [Cambridge Centre for Medical Materials, Materials Science and Metallurgy Department, University of Cambridge, Cambridge CB3 0FS (United Kingdom); Wardale, R. J., E-mail: pawelec.km@gmail.com, E-mail: jw626@cam.ac.uk [Division of Trauma and Orthopaedic Surgery, Department of Surgery, University of Cambridge, Cambridge CB2 2QQ (United Kingdom)

    2015-01-01

    Stability of the knee relies on the meniscus, a complex connective tissue with poor healing ability. Current meniscal tissue engineering is inadequate, as the signals for increasing meniscal cell proliferation have not been established. In this study, collagen scaffold structure, isotropic or aligned, and fibrin gel addition were tested. Metabolic activity was promoted by fibrin addition. Cellular proliferation, however, was significantly increased by both aligned architectures and fibrin addition. None of the constructs impaired collagen type I production or triggered adverse inflammatory responses. It was demonstrated that both fibrin gel addition and optimized scaffold architecture effectively promote meniscal cell proliferation.

  18. Flat Cellular (UMTS) Networks

    NARCIS (Netherlands)

    Bosch, H.G.P.; Samuel, L.G.; Mullender, Sape J.; Polakos, P.; Rittenhouse, G.

    Traditionally, cellular systems have been built in a hierarchical manner: many specialized cellular access network elements that collectively form a hierarchical cellular system. When 2G and later 3G systems were designed there was a good reason to make system hierarchical: from a cost-perspective

  19. Ultrastructure and elemental analysis of Hypoxis hemerocallidea : A ...

    African Journals Online (AJOL)

    The ultrastructure and crystal deposits of the plant were assessed using scanning electron microscopy (SEM), and energy dispersive x-ray (EDX). Results: It was observed that the leaves were characterised by multicelullar glandular and non glandular trichomes which are sparsely distributed over the entire surfaces.

  20. Ultrastructure of the lingual epithelium of adult scincine lizard ...

    African Journals Online (AJOL)

    In the present investigation, the histological and histochemical characteristics, as well as the ultrastructure of the lingual epithelium of the adult lizard Chalcides ocellatus, were investigated by light microscopy (LM) and scanning electron microscopy (SEM). Histological examination revealed taste buds and sensory papillae ...

  1. 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.

  2. Ultrastructural description of the corpora allata of Pimpla turionellae ...

    African Journals Online (AJOL)

    The corpora allata, are endocrine glands which produced juvenile hormone. In this study, corpora allata of adult females of Pimpla turionellae were examined ultrastructurally by using the transmission electron microscopy. The gland is surrounded with thick fibrous capsule that penetrates into the gland as a stromatal ...

  3. Investigations of ultrastructure of damaged and regenerated skeletal muscle fibers.

    Science.gov (United States)

    Lańcut, Mirosław; Godlewski, Piotr; Lis-Sochocka, Marta; Visconti, Józef; Czerny, Krystyna

    2004-01-01

    Our investigations concerned the head of the parietal part of quadriceps femoris, and we based our investigation on observations of the ultrastructure of muscle fibers using an electron microscope. We observed tissue samples taken from patients (10 men) 25-35 years old, who had old damage of knee joint ligament (after about 6 week's immobilization). In the first group, segments of tissue of parietal head of quadriceps femoris were taken inter-operationally from patients in whom there was found old damage of knee joint ligament. The second group was of tissue segments of this muscle after surgical repair of knee and rehabilitation, which consisted in power training using resistance machines. The muscle fiber samples of quadriceps femoris which were taken from patients during the first operation, showed big changes in their ultrastructure. These changes included: myofibrils disintegration; disturbance of regularly arranged striation in sarcomers; dissappearance of Z line. In the sarcoplasm, we observed large vacuolisation, and in the interfibrillar spaces--an accumulation of exudate and morphotic elements of blood outside the capillary vessels. Observations of muscle tissue after regeneration, showed a big improvement in the muscle cell's ultrastructure--the myofibrils were regularly arranged, and the sarcomers striations showed no deviations from normal structure. We also observed a considerable increase in the number of properly formed ultrastructure mitochondria when compared with the first group.

  4. 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.

  5. 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

  6. Ultrastructure comparison of the sensory morphology of the first- and ...

    African Journals Online (AJOL)

    Ultrastructure comparison of the sensory morphology of the first- and third-instar larvae of Parasarcophaga argyrostoma (Robineau-Desvoidy) (Diptera: Sarcophagidae). Azza Awad, Salah Abdel-Salam, Refat Abou El-Ela, Abdel-Aal Abdel-Aal, Doaa Mohamed ...

  7. Nuclear non-proliferation

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    DOE's nuclear non-proliferation responsibilities are defined by the provisions of the Atomic Energy Act of 1954, as amended, and of the Nuclear Non-Proliferation Act of 1978 (NNPA). The Department's major responsibilities in this area are to: (1) provide technical assistance to the Department of State in negotiating agreements for civil cooperation in the peaceful uses of nuclear energy with other countries and international organizations; (2) join with other agencies to reach executive branch judgments with respect to the issuance of export licenses by the Nuclear Regulatory Commission; (3) be responsible for processing subsequent arrangements with other agencies as required by the Nuclear Non-Proliferation Act; (4) control the distribution of special nuclear materials, components, equipment, and nuclear technology exports; (5) participate in bilateral and multilateral cooperation with foreign governments and organizations to promote the peaceful uses of nuclear energy; and (6) act as a primary technical resource with respect to US participation in the International Atomic Energy Agency

  8. Dynamics of nuclear proliferation

    International Nuclear Information System (INIS)

    Meyer, S.M.

    1984-01-01

    This book looks beyond policy disputes to make a systematic examination of the assumptions and contending hypotheses that constitute contemporary thinking on nuclear proliferation. Rather than determine who is right or wrong, the intent is to develop a better picture by using the various schools of thought as analytic windows. A better understanding of how the process operates should offer better guidance for predicting future nuclear proliferation and, ultimately, for controlling it. Separate chapters deal with the contending views, the technological and motivational bases of nuclear proliferation, the presence of a technological imperative, testing the motivational hypothesis, the dynamics of the process, and forecasting. Four appendices present historical decisions, the technical model, cost-estimating procedures, and procedures for estimating nuclear propensities. 288 references, 17 figures, 26 tables

  9. Cell proliferation in carcinogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, S.M.; Ellwein, L.B. (Univ. of Nebraska Medical Center, Omaha (USA))

    1990-08-31

    Chemicals that induce cancer at high doses in animal bioassays often fail to fit the traditional characterization of genotoxins. Many of these nongenotoxic compounds (such as sodium saccharin) have in common the property that they increase cell proliferation in the target organ. A biologically based, computerized description of carcinogenesis was used to show that the increase in cell proliferation can account for the carcinogenicity of nongenotoxic compounds. The carcinogenic dose-response relationship for genotoxic chemicals (such as 2-acetylaminofluorene) was also due in part to increased cell proliferation. Mechanistic information is required for determination of the existence of a threshold for the proliferative (and carcinogenic) response of nongenotoxic chemicals and the estimation of risk for human exposure.

  10. Thalidomide increases human keratinocyte migration and proliferation.

    Science.gov (United States)

    Nasca, M R; O'Toole, E A; Palicharla, P; West, D P; Woodley, D T

    1999-11-01

    Thalidomide is reported to have therapeutic utility in the treatment of pyoderma gangrenosum, Behçet's disease, aphthous ulcers, and skin wounds. We investigated the effect of thalidomide on human keratinocyte proliferation and migration, two early and critical events in the re-epithelialization of skin wounds. Thalidomide at concentrations less than 1 microM did not affect keratinocyte viability. Using a thymidine incorporation assay, we found that thalidomide, at therapeutic concentrations, induced more than a 2. 5-fold increase in the proliferative potential of the cells. Keratinocyte migration was assessed by two independent motility assays: a colloidal gold assay and an in vitro scratch assay. At optimal concentrations, thalidomide increased keratinocyte migration on a collagen matrix more than 2-fold in the colloidal gold assay and more than 3-fold in the scratch assay over control. Although pro-migratory, thalidomide did not alter the level of metalloproteinase-9 secreted into culture medium. Thalidomide did, however, induce a 2-4-fold increase in keratinocyte-derived interleukin-8, a pro-migratory cellular autocrine factor. Human keratinocyte migration and proliferation are essential for re-epithelialization of skin wounds. Interleukin-8 increases human keratinocyte migration and proliferation and is chemotactic for keratinocytes. Therefore, thalidomide may modulate keratinocyte proliferation and motility by a chemokine-dependent pathway.

  11. Effects of a 2X gravity environment on the ultrastructure of the gerbil parathyroid gland

    Science.gov (United States)

    Sannes, P. L.; Hayes, T. G.

    1975-01-01

    A number of studies concerning the effects of hypergravity on bone have shown increases in bone mass or bone dimensions. Correlative studies, which could provide clues to the mechanism for such a response, have been lacking. The purpose of the present study was to evaluate the ultrastructure of parathyroid glands of Mongolian gerbils exposed to a continuous 2 X gravity force for 60 d. It was found that the experimental animals had parathyroid glands which had a greater percentage of chief cells in the active stage of their secretory cycle when compared with control animals. This result was interpreted to indicate an increase in parathyroid gland secretory activity and, hence, an increase in parathyroid hormone release. It was suggested that increased parathyroid secretory activity was necessary to maintain serum calcium levels of hypergravity animals within normal limits. Cellular forms resembling water clear cells and highly compact, degenerating cells were described in experimental animals but not in controls. Areas suggestive of cellular dissolution and disorganization were also reported in experimental parathyroids.

  12. Ultra-structural morphology of long-term cultivated white adipose tissue-derived stem cells.

    Science.gov (United States)

    Varga, Ivan; Miko, Michal; Oravcová, Lenka; Bačkayová, Tatiana; Koller, Ján; Danišovič, Ľuboš

    2015-12-01

    White adipose tissue was long perceived as a passive lipid storage depot but it is now considered as an active and important endocrine organ. It also harbours not only adipocytes and vascular cells but also a wide array of immunologically active cells, including macrophages and lymphocytes, which may induce obesity-related inflammation. Recently, adipose tissue has been reported as a source of adult mesenchymal stem cells with wide use in regenerative medicine and tissue engineering. Their relatively non-complicated procurement and collection (often performed as liposuction during aesthetic surgery) and grand plasticity support this idea even more. We focused our research on exploring the issues of isolation and long-term cultivation of mesenchymal stem cells obtained from adipose tissue. Ultra-structural morphology of the cells cultivated in vitro has been studied and analysed in several cultivation time periods and following serial passages--up to 30 passages. In the first passages they had ultra-structural characteristics of cells with high proteosynthetic activity. Within the cytoplasm, big number of small lipid droplets and between them, sparsely placed, small and inconspicuous, electron-dense, lamellar bodies, which resembled myelin figures were observed. The cells from the later passages contained high number of lamellar electron-dense structures, which filled out almost the entire cytoplasm. In between, mitochondria were often found. These bodies were sometimes small and resembled myelin figures, but several of them reached huge dimensions (more than 1 µm) and their lamellar structure was not distinguishable. We did not have an answer to the question about their function, but they probably represented the evidence of active metabolism of lipids present in the cytoplasm of these cells or represented residual bodies, which arise after the breakdown of cellular organelles, notably mitochondria during long-term cultivation.

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

    KAUST Repository

    AlAbbadi, Shatha H.

    2016-12-01

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

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

    Directory of Open Access Journals (Sweden)

    Vítor Ennes-Vidal

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

  15. [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.

  16. Cell Proliferation in Neuroblastoma

    Science.gov (United States)

    Stafman, Laura L.; Beierle, Elizabeth A.

    2016-01-01

    Neuroblastoma, the most common extracranial solid tumor of childhood, continues to carry a dismal prognosis for children diagnosed with advanced stage or relapsed disease. This review focuses upon factors responsible for cell proliferation in neuroblastoma including transcription factors, kinases, and regulators of the cell cycle. Novel therapeutic strategies directed toward these targets in neuroblastoma are discussed. PMID:26771642

  17. anterior hyaloidal fibrovascular proliferation

    African Journals Online (AJOL)

    Okonkwo

    It most commonly occurs after phakic vitrectomy and scleral buckling for diabetic traction retinal detachment. It usually manifests with haemorrhage into the vitreous cavity or anterior hyaloid 3 to 12 weeks after vitrectomy and is the result of fibrovascular proliferation from the peripheral retina extending toward the equator of ...

  18. Particular molecular and ultrastructural aspects in invasive mammary carcinoma.

    Science.gov (United States)

    Mihalcea, Corina Elena; Moroşanu, Ana Maria; Murăraşu, Daniela; Puiu, Liliana; Cinca, Sabin; Voinea, Silviu Cristian; Mirancea, Nicolae

    2015-01-01

    Electron microscopic investigations of invasive mammary carcinoma tumors revealed that intercellular junctions, namely desmosomes are severely altered; some desmosomes became internalized. Tumor cells, especially by their invadopodia, generate and disseminate membrane vesicles, including exosomes, inside of peritumoral stroma. Telocytes, a new described interstitial/stromal cell phenotype, considered to play important roles in cell signaling, exhibited a reduced number of hetero-cellular contacts, which suggests a possible perturbation of tissular homeostasis modulation. Signaling PIK3/Akt pathway plays an important role both in carcinogenesis and in proliferation, differentiation, and cell survival. Alteration of this pathway has been observed in many human cancers, often involving an increase in the activity of PIK3CA, p110α catalytic subunit of PI3K. Our study confirms the high prevalence of PIK3CA mutations in breast cancer. In accordance with the results of the largest previous studies, 87.5% of mutations detected by DNA direct sequencing were hot spot mutations, most of them located in the kinase domain. High percentage of mutations detected by high-resolution melting makes the assay an attractive choice for mutation scanning, especially, in samples with low percentage of tumor cell.

  19. Peroxisome proliferator-activated receptor α-independent peroxisome proliferation

    International Nuclear Information System (INIS)

    Zhang Xiuguo; Tanaka, Naoki; Nakajima, Takero; Kamijo, Yuji; Gonzalez, Frank J.; Aoyama, Toshifumi

    2006-01-01

    Hepatic peroxisome proliferation, increases in the numerical and volume density of peroxisomes, is believed to be closely related to peroxisome proliferator-activated receptor α (PPARα) activation; however, it remains unknown whether peroxisome proliferation depends absolutely on this activation. To verify occurrence of PPARα-independent peroxisome proliferation, fenofibrate treatment was used, which was expected to significantly enhance PPARα dependence in the assay system. Surprisingly, a novel type of PPARα-independent peroxisome proliferation and enlargement was uncovered in PPARα-null mice. The increased expression of dynamin-like protein 1, but not peroxisome biogenesis factor 11α, might be associated with the PPARα-independent peroxisome proliferation at least in part

  20. Discoidin domain receptor 2 (DDR2) regulates proliferation of endochondral cells in mice

    International Nuclear Information System (INIS)

    Kawai, Ikuma; Hisaki, Tomoka; Sugiura, Koji; Naito, Kunihiko; Kano, Kiyoshi

    2012-01-01

    Highlights: ► Discoidin domain receptor 2 (DDR2) is a receptor tyrosine kinase. ► DDR2 regulates cell proliferation, cell adhesion, migration, and extracellular matrix remodeling. ► We produced in vitro and in vivo model to better understand the role of DDR2. ► DDR2 might play an inhibitory role in the proliferation of chondrocyte. -- Abstract: Discoidin domain receptor 2 (DDR2) is a receptor tyrosine kinase that is activated by fibrillar collagens. DDR2 regulates cell proliferation, cell adhesion, migration, and extracellular matrix remodeling. The decrement of endogenous DDR2 represses osteoblastic marker gene expression and osteogenic differentiation in murine preosteoblastic cells, but the functions of DDR2 in chondrogenic cellular proliferation remain unclear. To better understand the role of DDR2 signaling in cellular proliferation in endochondral ossification, we inhibited Ddr2 expression via the inhibitory effect of miRNA on Ddr2 mRNA (miDdr2) and analyzed the cellular proliferation and differentiation in the prechondrocyte ATDC5 cell lines. To investigate DDR2’s molecular role in endochondral cellular proliferation in vivo, we also produced transgenic mice in which the expression of truncated, kinase dead (KD) DDR2 protein is induced, and evaluated the DDR2 function in cellular proliferation in chondrocytes. Although the miDdr2-transfected ATDC5 cell lines retained normal differentiation ability, DDR2 reduction finally promoted cellular proliferation in proportion to the decreasing ratio of Ddr2 expression, and it also promoted earlier differentiation to cartilage cells by insulin induction. The layer of hypertrophic chondrocytes in KD Ddr2 transgenic mice was not significantly thicker than that of normal littermates, but the layer of proliferative chondrocytes in KD-Ddr2 transgenic mice was significantly thicker than that of normal littermates. Taken together, our data demonstrated that DDR2 might play a local and essential role in the

  1. Ultrastructural features of supraspinal muscles in rabbits after long-term transcutaneous lateral electrical surface stimulation (LESS

    Directory of Open Access Journals (Sweden)

    Mariusz Majewski

    2005-12-01

    Full Text Available Lateral electrical surface stimulation is one of methods used in the therapy of the progressive form of idiopathic scoliosis (IS in children and youth. However, there are data suggesting that this method may lead to serious adverse side effects, when used for a too long period of time per day. To clarify this issue, the present study was aimed at disclosing possible changes in the ultrastructural appearance of rabbit supraspinal muscles undergoing long-term stimulation (9 h per day, 3 months, an animal model successfully used to mimic the situation in humans. In comparison to the control animals, muscles of "overstimulated" rabbits exhibited clear signs of microscopical lesions, including depletion and disintegration of myofilaments, proliferation, dilatation and, sometimes, swelling of sarcoplasmic reticulum and/or mitochondria, as well as signs of destruction of the Z line. The above-mentioned abnormalities, especially the signs of degenerative processes associated with the Z line and the observed microlesions strongly suggest that the failure of the long-term LESS therapy of the IS may be attributable to these ultrastructural lesions.

  2. Odd-skipped related 2 regulates genes related to proliferation and development

    International Nuclear Information System (INIS)

    Kawai, Shinji; Abiko, Yoshimitsu; Amano, Atsuo

    2010-01-01

    Cell proliferation is a biological process in which chromosomes replicate in one cell and equally divide into two daughter cells. Our previous findings suggested that Odd-skipped related 2 (Osr2) plays an important role in cellular quiescence and proliferation under epigenetic regulation. However, the mechanism used by Osr2 to establish and maintain proliferation is unknown. To examine the functional role of Osr2 in cell proliferation, we analyzed its downstream target genes using microarray analysis following adenovirus-induced overexpression of Osr2 as well as knockdown with Osr2 siRNA, which showed that Osr2 regulates a multitude of genes involved in proliferation and the cell cycle, as well as development. Additional proliferation assays also indicated that Osr2 likely functions to elicit cell proliferation. Together, these results suggest that Osr2 plays important roles in proliferation and development.

  3. Ultrastructural Characterization of Fresh and Vitrified In Vitro- and In Vivo-Produced Sheep Embryos.

    Science.gov (United States)

    Romão, R; Bettencourt, E; Pereira, R M L N; Marques, C C; Baptista, M C; Barbas, J P; Oliveira, E; Bettencourt, C; Sousa, M

    2016-06-01

    The lower results in cryopreservation of in vitro-produced (IVP) sheep embryos, when compared to the in vivo derived, limits its use. Four groups of blastocyst (BL) were evaluated: fresh IVP (n = 3), fresh in vivo derived (n = 3), warmed IVP cryopreserved in open pulled straws (OPS, n = 3) and warmed in vivo derived cryopreserved in OPS (n = 3). Ultrastructural observation of processed fresh embryos showed a reduced number of microvilli and mitochondria in the IVP ones, as well as a lower number of mature mitochondria, that can be associated with deficient metabolism in IVP embryos, possibly involved in the lower resistance to cryopreservation. Both in vivo-derived and IVP embryos had a large number of vesicles, with light and dense content. In embryos vitrified by OPS, major changes were observed mainly in IVP embryos with small changes in grade 2 (fair) and high changes in grade 3 (bad) semithin scoring. The main changes associated with cryopreservation included disruption of cellular membranes and poor intracellular preservation, with loss of microvilli and the presence of cellular debris. In conclusion, ultrastructural evaluation of IVP blastocysts cryopreserved in OPS was herein described for the first time, reporting more severe cellular damage in these embryos when compared to those produced in vivo. This is probably associated with a lower cryotolerance that can be related to their lipid content and metabolism. © 2015 Blackwell Verlag GmbH.

  4. Cellular Adhesion Promotes Prostate Cancer Cells Escape from Dormancy.

    Science.gov (United States)

    Ruppender, Nazanin; Larson, Sandy; Lakely, Bryce; Kollath, Lori; Brown, Lisha; Coleman, Ilsa; Coleman, Roger; Nguyen, Holly; Nelson, Peter S; Corey, Eva; Snyder, Linda A; Vessella, Robert L; Morrissey, Colm; Lam, Hung-Ming

    2015-01-01

    Dissemination of prostate cancer (PCa) cells to the bone marrow is an early event in the disease process. In some patients, disseminated tumor cells (DTC) proliferate to form active metastases after a prolonged period of undetectable disease known as tumor dormancy. Identifying mechanisms of PCa dormancy and reactivation remain a challenge partly due to the lack of in vitro models. Here, we characterized in vitro PCa dormancy-reactivation by inducing cells from three patient-derived xenograft (PDX) lines to proliferate through tumor cell contact with each other and with bone marrow stroma. Proliferating PCa cells demonstrated tumor cell-cell contact and integrin clustering by immunofluorescence. Global gene expression analyses on proliferating cells cultured on bone marrow stroma revealed a downregulation of TGFB2 in all of the three proliferating PCa PDX lines when compared to their non-proliferating counterparts. Furthermore, constitutive activation of myosin light chain kinase (MLCK), a downstream effector of integrin-beta1 and TGF-beta2, in non-proliferating cells promoted cell proliferation. This cell proliferation was associated with an upregulation of CDK6 and a downregulation of E2F4. Taken together, our data provide the first clinically relevant in vitro model to support cellular adhesion and downregulation of TGFB2 as a potential mechanism by which PCa cells may escape from dormancy. Targeting the TGF-beta2-associated mechanism could provide novel opportunities to prevent lethal PCa metastasis.

  5. Proliferation in cycle

    Energy Technology Data Exchange (ETDEWEB)

    Piao Yunsong [College of Physical Sciences, Graduate School of Chinese Academy of Sciences, Beijing 100049 (China)], E-mail: yspiao@gucas.ac.cn

    2009-06-15

    In the contracting phase with w{approx_equal}0, the scale invariant spectrum of curvature perturbation is given by the increasing mode of metric perturbation. In this Letter, it is found that if the contracting phase with w{approx_equal}0 is included in each cycle of a cycle universe, since the metric perturbation is amplified on super horizon scale cycle by cycle, after each cycle the universe will be inevitably separated into many parts independent of one another, each of which corresponds to a new universe and evolves up to next cycle, and then is separated again. In this sense, a cyclic multiverse scenario is actually presented, in which the universe proliferates cycle by cycle. We estimate the number of new universes proliferated in each cycle, and discuss the implications of this result.

  6. JPRS Report, Proliferation Issues

    Science.gov (United States)

    1992-10-21

    Plutonium Cargo Rejected [LA TERCERA DE LA HORA 8 Oct] .................. 7 URUGUAY Nuclear Energy Agreement With Canada Shelved [BUSQUEDA 2 Oct...will monitor the shipment via there is concern over proliferation, such as South Africa, satellite, the Middle East and the Korean peninsula. As to the...Santiago IA TERCERA DE LA HORA national Affairs Commissions with the only opposition in Spanish 8 Oct 92 p 16 coming from the Herreraist faction congressmen

  7. Cyclooxygenases; Proliferation and differentiation

    African Journals Online (AJOL)

    sayeh

    2012-11-08

    Nov 8, 2012 ... Cyclooxygenase-1 (cox-1) is a constitutively expressed enzyme in most mammalian tissues and maintains normal cellular physiological. *Corresponding author. E-mail: hamidr.ahmadi@yahoo.com. Tel: +98(912) 8055498. functions, such as platelet aggregation and gastric cytoprotection (Mehmet et al., ...

  8. Linearizable cellular automata

    International Nuclear Information System (INIS)

    Nobe, Atsushi; Yura, Fumitaka

    2007-01-01

    The initial value problem for a class of reversible elementary cellular automata with periodic boundaries is reduced to an initial-boundary value problem for a class of linear systems on a finite commutative ring Z 2 . Moreover, a family of such linearizable cellular automata is given

  9. Ultrastructure of spermatogenesis in the testis of Paragonimus heterotremus.

    Science.gov (United States)

    Uabundit, Nongnut; Kanla, Pipatphong; Puthiwat, Phongphithak; Arunyanart, Channarong; Chaiciwamongkol, Kowit; Maleewong, Wanchai; Intapan, Pewpan M; Iamsaard, Sitthichai; Hipkaeo, Wiphawi

    2013-12-01

    Lung fluke, Paragonimus heterotremus, is a flatworm causing pulmonary paragonimiasis in cats, dogs, and humans in Southeast Asia. We examined the ultrastructure of the testis of adult P. heterotremus with special attention to spermatogenesis and spermiogenesis using scanning and transmission electron microscopy. The full sequence of spermatogenesis and spermiogenesis, from the capsular basal lamina to the luminal surface, was demonstrated. The sequence comprises spermatogonia, spermatocytes with obvious nuclear synaptonemal complexes, spermatids, and eventual spermatozoa. Moreover, full steps of spermatid differentiation were shown which consisted of 1) early stage, 2) differentiation stage representing the flagella, intercentriolar body, basal body, striated rootlets, and electron dense nucleus of thread-like lamellar configuration, and 3) growing spermatid flagella. Detailed ultrastructure of 2 different types of spermatozoa was also shown in this study.

  10. Crohn's disease: ultrastructure of interstitial cells in colonic myenteric plexus

    DEFF Research Database (Denmark)

    Rumessen, Jüri Johs.; Vanderwinden, Jean-Marie; Horn, Thomas

    2011-01-01

    -MP and other interstitial cells in the myenteric region of the colon are lacking for CD. In the present study, we characterized the ultrastructure of interstitial cells, nerves, and glial cells in the myenteric region in Crohn's colitis (CC). In comparison with controls, varicosities of the myenteric bundles...... were dilated and appeared to be empty. Lipid droplets and lipofuscin-bodies were prominent in glial cells and neurons. ICC-MP were scanty but, as in controls, had caveolae, prominent intermediate filaments, cytoplasmic dense bodies, and membrane-associated dense bands with a patchy basal lamina. ICC......The role of the interstitial cells of Cajal (ICC) in chronic inflammatory bowel disease, i.e., ulcerative colitis (UC) and Crohn's disease (CD), remains unclear. Ultrastructural alterations in ICC in the colonic myenteric plexus (ICC-MP) have been reported previously in UC, but descriptions of ICC...

  11. Morphological and ultrastructural characterization of sea urchin immune cells.

    Science.gov (United States)

    Deveci, Remziye; Şener, Ecem; İzzetoğlu, Savaş

    2015-05-01

    The free circulating coelomocytes in the coelomic cavity of echinoderms are considered to be immune effectors by phagocytosis, encapsulation, cytotoxicity, and by the production of antimicrobial agents. Although echinoderms (especially sea urchin embryo) have been used as a model organisms in biology, no uniform criteria exist for classification of coelomocytes in echinoderms, and few studies have reported about the biological functions of their coelomocytes. Hence, we study the coelomocytes in the echinoid sea urchin, Paracentrotus lividus, and describe their morphological and ultrastructural features using light and transmission electron microscopes. We classify the coelomocytes of P. lividus into red spherule and colorless spherule cells, small cells, vibratile cells, and phagocytic cells; petaloid and filopodial cells. To our knowledge, this is the first report describing ultrastructural details of the coelomocytes of P. lividus. © 2015 Wiley Periodicals, Inc.

  12. Ultrastructure of Withania Somnifera (L.) Dunal pollen grains

    International Nuclear Information System (INIS)

    Alwadie, H.M.

    2002-01-01

    Light, scanning and transmission electron microscopy were used to study the morphology and ultrastructure of Withania Somnifera (L.) Dunall pollen grains. Light microscopic examination revealed that the pollen grains are tri- or tetrazonocoplate grains, approximately as long as broad, measuring 29-um. Scanning electron microscopic observation showed that surface sculpturing of the pollen is scarbate-granulate. Ultrathin sections as examined by transmission electron microscope showed that the pollen contained numerous starch grains, lipid droplets, endoplasmic reticulum and vesicles of dictyosomes. Two layers of the pollen wall were also distinguished, the outer wall (exine) divided into ektexine and endexine as well as the inner layer (intine). The nutritive values of Withania pollen are discussed. The importance of studying the ultrastructure of pollen grains as a new tool in palynology is also discussed. (author)

  13. Ultrastructural localization of 5-methylcytosine on DNA and RNA.

    Science.gov (United States)

    Masiello, Irene; Biggiogera, Marco

    2017-08-01

    DNA methylation is the major epigenetic modification and it is involved in the negative regulation of gene expression. Its alteration can lead to neoplastic transformation. Several biomolecular approaches are nowadays used to study this modification on DNA, but also on RNA molecules, which are known to play a role in different biological processes. RNA methylation is one of the most common RNA modifications and 5-methylcytosine presence has recently been suggested in mRNA. However, an analysis of nucleic acid methylation at electron microscope is still lacking. Therefore, we visualized DNA methylation status and RNA methylation sites in the interphase nucleus of HeLa cells and rat hepatocytes by ultrastructural immunocytochemistry and cytochemical staining. This approach represents an efficient alternative to study nucleic acid methylation. In particular, this ultrastructural method makes the visualization of this epigenetic modification on a single RNA molecule possible, thus overcoming the technical limitations for a (pre-)mRNA methylation analysis.

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

    Science.gov (United States)

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

    2013-10-01

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

  15. Effects of the presence of indium on the mammary gland ultrastructure, body weight, food intake and plasmatic prolactin concentration.

    Science.gov (United States)

    Ayadi, Ahlem; Maghraoui, Samira; Kammoun, Sayda; Tekaya, Leila

    2014-10-01

    Several studies have demonstrated the toxic effect of indium. This element induces impairments in many organs such as spleen, lungs and testicles after its systemic administration. Teratogenic and embryotoxic effects of this element have also been established. In the present study, we attempt to investigate the histological and the ultrastructural consequences of the presence of this element in mammary gland tissue using conventional transmission electron microscopy and to evaluate the incidences of its presence on the food intake, body weight and prolactin plasmatic concentration of lactating female rats. Our study showed that this element induced a significant decrease in food intake and body weight, and caused some cellular damage in the glandular epithelial cell such as cytoplasmic vacuolization and expansion of the ergastoplasm. The ultrastructural observations also showed many electron-dense surcharges in the lysosomes of the glandular epithelial cells. The electron probe microanalysis showed that these deposits are composed of indium and phosphorus. The lysosomes, known for their protective role of sequestrating foreign elements to avoid their diffusion in the blood, failed to stop the toxic effect of indium. © The Author 2014. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

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

    Science.gov (United States)

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

    2011-08-01

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

  17. High resolution imaging of the ultrastructure of living algal cells using soft x-ray contact microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ford, T.W.; Cotton, R.A.; Page, A.M. [Univ. of London, Egham (United Kingdom). School of Biological Sciences; Tomie, T.; Majima, T.; Stead, A.D. [Electrotechnical Lab., Tsukuba, Ibaraki (Japan)

    1995-12-31

    Soft x-ray contact microscopy provides the biologist with a technique for examining the ultrastructure of living cells at a much higher resolution than that possible by various forms of light microscopy. Readout of the developed photoresist using atomic force microscopy (AFM) produces a detailed map of the carbon densities generated in the resist following exposure of the specimen to water-window soft x-rays (2--4nm) produced by impact of a high energy laser onto a suitable target. The established high resolution imaging method of transmission electron microscopy (TEM) has inherent problems in the chemical pre-treatment required for producing the ultrathin sections necessary for this technique. Using the unicellular green alga Chlamydomonas the ultrastructural appearance of the cells following SXCM and TEM has been compared. While SXCM confirms the basic structural organization of the cell as seen by TEM (e.g., the organization of the thylakoid membranes within the chloroplast; flagellar insertion into the cytoplasm), there are important differences. These are in the appearance of the cell covering and the presence of carbon-dense spherical cellular inclusions.

  18. Histochemical and ultrastructural study of adult human tendon.

    Science.gov (United States)

    Józsa, L; Bálint, J B; Réffy, A; Demel, Z

    1979-01-01

    The authors have studied the enzymhistochemical and ultrastructural pictures of tenocytes of adult human tendons. High succinate dehydrogenase, cytochrome oxidase, TPN-diaphorase, lactate dehydrogenase and glucose-6-phosphate dehydrogenase activity were found, as indicated both oxidativ, anaerobic and pentose-phosphate shung activity. Phosphorylase and glutamate dehydrogenase activity was medial, lipase and alcaline phosphatase activity was slight. In tenocytes well developed rough endoplasmic reticulum and GOLGI apparatus, large amount of free ribosomes were found.

  19. Behavioural and ultrastructural activity relationship as early warning ...

    African Journals Online (AJOL)

    Heterogeneous sexes of fish consisting of 18 females (gravid and non-gravid), and 9 males, in three replicates, were separately exposed to spinosad (49 and 110 μgL-1) and chlorpyrifos (0.4 and 0.8 μgL-1) at dosages that did not cause physical death for 28-days under static renewal bioassay with control. Ultrastructural ...

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

    Science.gov (United States)

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

    2018-01-23

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

  1. Proliferation after the Iraq war

    International Nuclear Information System (INIS)

    Daguzan, J.F.

    2004-09-01

    This article uses the Iraq war major event to analyze the approach used by the US to fight against proliferation. It questions the decision and analysis process which has led to the US-British intervention and analyzes the consequences of the war on the proliferation of other countries and on the expected perspectives. Finally, the future of proliferation itself is questioned: do we have to fear more threat or is the virtuous circle of non-proliferation well started? (J.S.)

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

    Directory of Open Access Journals (Sweden)

    Heinz Horstmann

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

  3. Ultrastructural Changes in the Liver of Intravenous Heroin Addicts

    Directory of Open Access Journals (Sweden)

    Goran Ilić

    2010-02-01

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

  4. A review of the ultrastructural features of superficial candidiasis.

    Science.gov (United States)

    Jayatilake, J A M S

    2011-04-01

    Commensal yeast Candida causes opportunistic infections ranging from superficial lesions to disseminated mycoses in compromised patients. Superficial candidiasis, the commonest form of candidal infections, primarily affects the mucosa and the skin where Candida lives as a commensal. Conversion of candidal commensalism into opportunism at the fungal-epithelial interface is still ill-defined. Nevertheless, fungal virulence mechanisms such as adhesion to epithelia, morphogenesis, production of secretory hydrolytic enzymes, and phenotypic switching are thought to contribute in the process of pathogenesis. On the other hand, host responses in terms of immunity and local epithelial responses are actively involved in resisting the fungal challenge at the advancing front of the infection. Ultrastructural investigations using electron microscopy along with immunohistochemistry, cytochemistry, etc. have helped better viewing of Candida-host interactions. Thus, studies on the ultrastructure of superficial candidiasis have revealed a number of fungal behaviors and associated host responses such as adhesion, morphogenesis (hyphae and appresoria formation), thigmotropism, production and distribution of extracellular enzymes, phagocytosis, and epithelial changes. The purpose of this review is to sum up most of the ultrastructural findings of Candida-host interactions and to delineate the important pathological processes underlying superficial candidiasis.

  5. 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)

  6. Ultrastructural mitochondrial alterations in equine myopathies of unknown origin.

    Science.gov (United States)

    Van Driessche, K; Ducatelle, R; Chiers, K; Van Coster, R; van der Kolk, J H; van der Kolk, H

    2015-03-01

    Very few mitochondrial myopathies have been described in horses. To examine the ultrastructure of muscle mitochondria in equine cases of myopathy of unknown origin. Biopsies of vastus lateralis of the Musculus quadriceps femoris were taken predominantly immediately post mortem and processed for transmission electron microscopy. As a result, electron micrographs of 90 horses in total were available for analysis comprising 4 control horses, 16 horses suffering from myopathy and 70 otherwise diseased horses. Following a thorough clinical and laboratory work-up, four out of five patients that did not fit into the usual algorithm to detect known causes of myopathy showed ultrastructural mitochondrial alterations. Small mitochondria with zones with complete disruption of cristae associated with lactic acidemia were detected in a 17-year-old pony mare, extremely long and slender mitochondria with longitudinal cristae in a 5-year-old Quarter horse stallion, a mixture of irregular extremely large mitochondria (measuring 2500 by 800 nm) next to smaller ones in an 8-year-old Hanoverian mare and round mitochondria with only few cristae in a 11-year-old pony gelding. It remains uncertain whether the subsarcolemmal mitochondrial accumulations observed in the fifth patient have any pathological significance. Ultrastructural alterations in mitochondria were detected in at least four horses. To conclude that these are due to mitochondrial dysfuntions, biochemical tests should be performed. The possibility of a mitochondrial myopathy should be included in the differential diagnosis of muscle weakness.

  7. Morphology, proliferation, and osteogenic differentiation of mesenchymal stem cells cultured on titanium, tantalum, and chromium surfaces

    DEFF Research Database (Denmark)

    Stiehler, Maik; Lind, M.; Mygind, Tina

    2007-01-01

    the interactions between human mesenchymal stem cells (MSCs) and smooth surfaces of titanium (Ti), tantalum (Ta), and chromium (Cr). Mean cellular area was quantified using fluorescence microscopy (4 h). Cellular proliferation was assessed by (3)H-thymidine incorporation and methylene blue cell counting assays (4...

  8. The immunological phenotype and ultrastructure of blood lymphocytes of children with the diagnosis of thyroid cancer who lived near the Chernobyl NPS

    International Nuclear Information System (INIS)

    Tron'ko, N.D.; Zak, K.P.; Gruzov, M.A.; Afanas'eva, V.V.; Bol'shova, E.V.; Vishnevskaya, O.A.

    1999-01-01

    On the flow cytometric and electron microscopic study of blood cells in children with papillary thyroid cancer, who lived near the Chernobyl Nuclear Power Station, we revealed a decrease in the number and changes in the ultrastructure of T-lymphocytes (CD3+ cells), T-helpers (CD4+ cells), and NK cells (CD56+cells) as well as eosinophilia. We suggest that the impairment of T-cellular and natural immunity may be a promoting factor of the malignant transformation of thyrocytes induced by radioiodine

  9. Establishment of four new mesothelioma cell lines: characterization by ultrastructural and immunophenotypic analysis.

    Science.gov (United States)

    Orengo, A M; Spoletini, L; Procopio, A; Favoni, R E; De Cupis, A; Ardizzoni, A; Castagneto, B; Ribotta, M; Betta, P G; Ferrini, S; Mutti, L

    1999-03-01

    The aim of this study was to assess the biological characteristics of four new malignant mesothelioma (MM) cell lines. Since simian virus (SV)40 sequences have been recently detected in MM, SV40 large T antigen (Tag) expression was also analysed. MM cell lines were characterized by morphological, ultrastructural and cytogenetic analysis. Expression of Tag and of relevant MM markers was studied by immunocytochemistry, surface antigens by indirect immunofluorescence and immunomodulating cytokines by enzyme-linked immunosorbent assay (ELISA). The four MM cell lines, established from pleural effusions, showed a slow proliferation rate and pleomorphic changes during culture. Cell lines expressed vimentin, cytokeratins 8 and 18, and the mesothelial antigen recognized by HBME-1 monoclonal antibody, but not carcinoembryonic antigen. Surface human leukocyte antigen (HLA)-class I and intercellular adhesion molecule (ICAM)-1 molecules were present on all the cell lines. While HLA class II and CD86 were constitutively undetectable, HLA-class II was present after interferon (IFN)-gamma stimulation. All cell lines displayed abnormal karyotypes with chromosome 6 abnormalities. Transforming growth factor (TGF)-beta2 and interleukin (IL)-6 were constitutively secreted, while tumour necrosis factor (TNF)-alpha was secreted only in response to lipopolysaccharide. Intranuclear Tag was expressed in two cell lines. The persistence of large T antigen with human leukocyte antigen class I and intercellular adhesion molecule-1 positivity may point to large T antigen as a target for cytotoxic T-lymphocyte-based immunotherapy in some malignant mesothelioma patients.

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

    Directory of Open Access Journals (Sweden)

    Harumi Mizuki

    2017-09-01

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

  11. Ultrastructural Changes during the Life Cycle ofMycoplasma salivariumin Oral Biopsies from Patients with Oral Leukoplakia.

    Science.gov (United States)

    Mizuki, Harumi; Abe, Ryosuke; Mikami, Toshinari

    2017-01-01

    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. salivarium

  12. [Neuroendocrine tumors of digestive system: morphologic spectrum and cell proliferation (Ki67 index)].

    Science.gov (United States)

    Delektorskaia, V V; Kushliskiĭ, N E

    2013-01-01

    This review deals with the analysis of up-to-date concepts ofdiferent types of human neuroendocrine tumors of the digestive system. It summarizes the information on the specifics of recent histological classifications and criteria of morphological diagnosis accounting histological, ultrastructural and immunohistochemical parameters. Current issues of the nomenclature as well as various systems of grading and staging are discussed. In the light of these criteria the results of the own research clinical value of the determination of cell proliferation in primary and metastatic gastroenteropancreatic neuroendocrine neoplasms on the basis of evaluation of the Ki67 antigen expression are also presented.

  13. Plasmonic Nanostructured Cellular Automata

    Science.gov (United States)

    Alkhazraji, Emad; Ghalib, A.; Manzoor, K.; Alsunaidi, M. A.

    2017-03-01

    In this work, we have investigated the scattering plasmonic resonance characteristics of silver nanospheres with a geometrical distribution that is modelled by Cellular Automata using time-domain numerical analysis. Cellular Automata are discrete mathematical structures that model different natural phenomena. Two binary one-dimensional Cellular Automata rules are considered to model the nanostructure, namely rule 30 and rule 33. The analysis produces three-dimensional scattering profiles of the entire plasmonic nanostructure. For the Cellular Automaton rule 33, the introduction of more Cellular Automata generations resulted only in slight red and blue shifts in the plasmonic modes with respect to the first generation. On the other hand, while rule 30 introduced significant red shifts in the resonance peaks at early generations, at later generations however, a peculiar effect is witnessed in the scattering profile as new peaks emerge as a feature of the overall Cellular Automata structure rather than the sum of the smaller parts that compose it. We strongly believe that these features that emerge as a result adopting the different 256 Cellular Automata rules as configuration models of nanostructures in different applications and systems might possess a great potential in enhancing their capability, sensitivity, efficiency, and power utilization.

  14. The microspores of Pleuromeia rossica Neuburg (Lycopsida; Triassic): Comparative ultrastructure and phylogenetic implications

    Science.gov (United States)

    Lugardon, Bernard; Grauvogel-Stamm, Léa; Dobruskina, Inna

    1999-09-01

    The ultrastructural features of the microspores of the Triassic lycopsid Pleuromeia rossica are similar to those of the microspores of the living Isoetes, except that the latter have an additional outermost wall. These features differ greatly from those of the spores of all the other extant Pteridophyta. Likewise, the megaspores of P. rossica, of which the comparative analysis will be presented later, are also ultrastructurally analogous to the megaspores of Isoetes. These ultrastructural similarities very likely imply close relationships between Pleuromeia and Isoetes. Moreover they suggest that these genera belong to a distinct group among the heterosporous lycopsids, in which the ultrastructural features of the microspores remained outstandingly steady.

  15. Dual effect of LPS on murine myeloid leukemia cells: Pro-proliferation and anti-proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Lingling [Department of Pediatrics, Jingjiang People' s Hospital, Yangzhou University, Jingjiang 214500 (China); Noncoding RNA Center, Yangzhou University, Yangzhou 225001 (China); Zhao, Yingmin [Department of Pediatrics, Jingjiang People' s Hospital, Yangzhou University, Jingjiang 214500 (China); Gu, Xin; Wang, Jijun; Pang, Lei; Zhang, Yanqing; Li, Yaoyao; Jia, Xiaoqin; Wang, Xin [Noncoding RNA Center, Yangzhou University, Yangzhou 225001 (China); Gu, Jian [Department of Hematology, Yangzhou University School of Clinical Medicine, Yangzhou 225001 (China); Yu, Duonan, E-mail: duonan@yahoo.com [Department of Pediatrics, Jingjiang People' s Hospital, Yangzhou University, Jingjiang 214500 (China); Noncoding RNA Center, Yangzhou University, Yangzhou 225001 (China); Jiangsu Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment of Senile Disease, Yangzhou 225001 (China); Institute of Comparative Medicine, Yangzhou University, Yangzhou 225001 (China); Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Disease and Zoonosis, Yangzhou 225001 (China)

    2016-06-10

    Modification of the bone marrow microenvironment is considered as a promising strategy to control leukemic cell proliferation, diseases progression and relapse after treatment. However, due to the diversity and complexity of the cellular and molecular compartments in the leukemic microenvironment, it is extremely difficult to dissect the role of each individual molecule or cell type in vivo. Here we established an in vitro system to dissect the role of lipopolysaccharide (LPS), stromal cells and endothelial cells in the growth of mouse myeloid tumor cells and B-lymphoma cells. We found that either LPS or bone marrow stromal cells as a feeder layer in culture is required for the proliferation of myeloid tumor cells. Surprisingly, the growth of myeloid leukemic cells on stromal cells is strongly inhibited when coupled with LPS in culture. This opposing effect of LPS, a complete switch from pro-proliferation to antitumor growth is due, at least in part, to the rapidly increased production of interleukin 12, Fas ligand and tissue inhibitor of metalloproteinases-2 from stromal cells stimulated by LPS. These results demonstrate that LPS can either facilitate or attenuate tumor cell proliferation, thus changing the disease course of myeloid leukemias through its direct effect or modulation of the tumor microenvironment. - Highlights: • LPS alone in culture is required for the proliferation of murine myeloid tumor cells. • Bone marrow stromal cells as a feeder layer is also required for the proliferation of myeloid tumor cells. • However, the growth of myeloid tumor cells is inhibited when LPS and stromal cells are both available in culture. • Thus LPS can either facilitate or attenuate tumor growth through its direct effect or modulation of tumor microenvironment.

  16. Dual effect of LPS on murine myeloid leukemia cells: Pro-proliferation and anti-proliferation

    International Nuclear Information System (INIS)

    Yu, Lingling; Zhao, Yingmin; Gu, Xin; Wang, Jijun; Pang, Lei; Zhang, Yanqing; Li, Yaoyao; Jia, Xiaoqin; Wang, Xin; Gu, Jian; Yu, Duonan

    2016-01-01

    Modification of the bone marrow microenvironment is considered as a promising strategy to control leukemic cell proliferation, diseases progression and relapse after treatment. However, due to the diversity and complexity of the cellular and molecular compartments in the leukemic microenvironment, it is extremely difficult to dissect the role of each individual molecule or cell type in vivo. Here we established an in vitro system to dissect the role of lipopolysaccharide (LPS), stromal cells and endothelial cells in the growth of mouse myeloid tumor cells and B-lymphoma cells. We found that either LPS or bone marrow stromal cells as a feeder layer in culture is required for the proliferation of myeloid tumor cells. Surprisingly, the growth of myeloid leukemic cells on stromal cells is strongly inhibited when coupled with LPS in culture. This opposing effect of LPS, a complete switch from pro-proliferation to antitumor growth is due, at least in part, to the rapidly increased production of interleukin 12, Fas ligand and tissue inhibitor of metalloproteinases-2 from stromal cells stimulated by LPS. These results demonstrate that LPS can either facilitate or attenuate tumor cell proliferation, thus changing the disease course of myeloid leukemias through its direct effect or modulation of the tumor microenvironment. - Highlights: • LPS alone in culture is required for the proliferation of murine myeloid tumor cells. • Bone marrow stromal cells as a feeder layer is also required for the proliferation of myeloid tumor cells. • However, the growth of myeloid tumor cells is inhibited when LPS and stromal cells are both available in culture. • Thus LPS can either facilitate or attenuate tumor growth through its direct effect or modulation of tumor microenvironment.

  17. Heterogeneous cellular networks

    CERN Document Server

    Hu, Rose Qingyang

    2013-01-01

    A timely publication providing coverage of radio resource management, mobility management and standardization in heterogeneous cellular networks The topic of heterogeneous cellular networks has gained momentum in industry and the research community, attracting the attention of standardization bodies such as 3GPP LTE and IEEE 802.16j, whose objectives are looking into increasing the capacity and coverage of the cellular networks. This book focuses on recent progresses,  covering the related topics including scenarios of heterogeneous network deployment, interference management i

  18. Can we predict nuclear proliferation

    International Nuclear Information System (INIS)

    Tertrais, Bruno

    2011-01-01

    The author aims at improving nuclear proliferation prediction capacities, i.e. the capacities to identify countries susceptible to acquire nuclear weapons, to interpret sensitive activities, and to assess nuclear program modalities. He first proposes a retrospective assessment of counter-proliferation actions since 1945. Then, based on academic studies, he analyzes what causes and motivates proliferation, with notably the possibility of existence of a chain phenomenon (mechanisms driving from one program to another). He makes recommendations for a global approach to proliferation prediction, and proposes proliferation indices and indicators

  19. JPRS Report, Proliferation Issues

    Science.gov (United States)

    1992-05-27

    JPRS-TND-92-016 27 MAY 1992 JPRS Repor Proliferation Issues ÄBpxovea tcz pursue ieiaaM| Ipfe. fötmbuasa OsüoaÜBd .^L ■ — —— au »** 19980112...6 MOROCCO Berrada on Proposed Nuclear Power Plant [ MAROC SOIR 22 Apr] 6 JPRS-TND-92-016 27 May 1992 2 CENTRAL EURASIA Proposals on...three days of talks here on normalizing relations with Japan, which were largely stalemated over Tokyo’s demand for Pyongyang’s assurance that it did

  20. Ultrastructure of single cells, callus-like and monospore-like cells in Porphyra yezoensis ueda on semisolid culture medium

    Science.gov (United States)

    Mei, Junxue; Shen, Songdong; Jiang, Ming; Fei, Xiugeng

    2003-06-01

    It had been demonstrated that individual cells or protoplasts isolated from Porphyra thallus by enzyme could develop into normal leafy thalli in the same way as monospores, and that isolated cells develop in different way in liquid and on semi-solid media. The authors observed the ultrastructure of isolated vegetative cells cultured on semi-solid media and compared them with those of monospores and isolated cells cultured in liquid media. The results showed that subcellular structures were quite different among cells in different conditions. In their development, isolated cells on semi-solid media did not show the characteristic subcellular feature of monospore formation, such as production of fibrous vesicles. Callus-like cells formed on semi-solid media underwent a distinctive modification in cellular organization. They developed characteristic cell inclusions and a special 2-layer cell covering. Golgi bodies, ER, starch grains, mitochondria. Vacuoles were not commonly found in them.

  1. Sphingosine-1-phosphate stimulates rat primary chondrocyte proliferation

    International Nuclear Information System (INIS)

    Kim, Mi-Kyoung; Lee, Ha Young; Kwak, Jong-Young; Park, Joo-In; Yun, Jeanho; Bae, Yoe-Sik

    2006-01-01

    Rat primary chondrocytes express the sphingosine-1-phosphate (S1P) receptor, S1P 2 , S1P 3 , S1P 4 , but not S1P 1 . When chondrocytes were stimulated with S1P or phytosphingosine-1-phosphate (PhS1P, an S1P 1 - and S1P 4 -selective agonist), phospholipase C-mediated cytosolic calcium increase was dramatically induced. S1P and PhS1P also stimulated two kinds of mitogen-activated protein kinases, extracellular signal-regulated kinase (ERK) and p38 kinase in chondrocytes. In terms of the two phospholipids-mediated functional modulation of chondrocytes, S1P and PhS1P stimulated cellular proliferation. The two phospholipids-induced chondrocyte proliferations were almost completely blocked by PD98059 but not by SB203580, suggesting that ERK but not p38 kinase is essentially required for the proliferation. Pertussis toxin almost completely inhibited the two phospholipids-induced cellular proliferation and ERK activation, indicating the crucial role of G i protein. This study demonstrates the physiological role of two important phospholipids (S1P and PhS1P) on the modulation of rat primary chondrocyte proliferation, and the crucial role played by ERK in the process

  2. Modeling cellular systems

    CERN Document Server

    Matthäus, Franziska; Pahle, Jürgen

    2017-01-01

    This contributed volume comprises research articles and reviews on topics connected to the mathematical modeling of cellular systems. These contributions cover signaling pathways, stochastic effects, cell motility and mechanics, pattern formation processes, as well as multi-scale approaches. All authors attended the workshop on "Modeling Cellular Systems" which took place in Heidelberg in October 2014. The target audience primarily comprises researchers and experts in the field, but the book may also be beneficial for graduate students.

  3. Cellular MR Imaging

    OpenAIRE

    Michel Modo; Mathias Hoehn; Jeff W.M. Bulte

    2005-01-01

    Cellular MR imaging is a young field that aims to visualize targeted cells in living organisms. In order to provide a different signal intensity of the targeted cell, they are either labeled with MR contrast agents in vivo or prelabeled in vitro. Either (ultrasmall) superparamagnetic iron oxide [(U)SPIO] particles or (polymeric) paramagnetic chelates can be used for this purpose. For in vivo cellular labeling, Gd3+- and Mn2+- chelates have mainly been used for targeted hepatobiliary imaging, ...

  4. Magnetohydrodynamic cellular automata

    International Nuclear Information System (INIS)

    Hatori, Tadatsugu

    1990-01-01

    There has been a renewal of interest in cellular automata, partly because they give an architecture for a special purpose computer with parallel processing optimized to solve a particular problem. The lattice gas cellular automata are briefly surveyed, which are recently developed to solve partial differential equations such as hydrodynamics or magnetohydrodynamics. A new model is given in the present paper to implement the magnetic Lorentz force in a more deterministic and local procedure than the previous one. (author)

  5. Initiatives for proliferation prevention

    International Nuclear Information System (INIS)

    1997-04-01

    Preventing the proliferation of weapons of mass destruction is a central part of US national security policy. A principal instrument of the Department of Energy's (DOE's) program for securing weapons of mass destruction technology and expertise and removing incentives for scientists, engineers and technicians in the newly independent states (NIS) of the former Soviet Union to go to rogue countries or assist terrorist groups is the Initiatives for Proliferation Prevention (IPP). IPP was initiated pursuant to the 1994 Foreign Operations Appropriations Act. IPP is a nonproliferation program with a commercialization strategy. IPP seeks to enhance US national security and to achieve nonproliferation objectives by engaging scientists, engineers and technicians from former NIS weapons institutes; redirecting their activities in cooperatively-developed, commercially viable non-weapons related projects. These projects lead to commercial and economic benefits for both the NIS and the US IPP projects are funded in Russian, Ukraine, Kazakhstan and Belarus. This booklet offers an overview of the IPP program as well as a sampling of some of the projects which are currently underway

  6. Non Proliferation of Nuclear

    International Nuclear Information System (INIS)

    Bambang S Irawan

    2004-01-01

    Non-Proliferation Treaty of Nuclear Weapons is the international community's efforts to maintain the security of the world, in order to prevent the spread of nuclear technology and the use of nuclear weapons, promoting cooperation for the use of nuclear peaceful purposes, build mutual trust (Confidence Building Measures) as well as to achieve the ultimate goal of disarmament overall (General and Complete Disarmament). Addressing the post-WTC tragedy, 11 September 2001, the Indonesian government should set up a National Measures (National Action Plan), among others formed the National Security Council and NBC Counter Proliferation Unit, or the National Authority for Nuclear Treaty, preparing national legislation, to prevent the abuse nuclear materials for terrorist acts, prevent Illicit Trafficking of Nuclear materials, developed a National Preparedness and Emergency Response Management in the event of a nuclear accident or attack by the use of nuclear terrorism. Importance of a National Action Plan meant the existence of a national commitment in the context of compliance with treaties and conventions which have been ratified relating to safety, security, safeguards towards a general and complete disarmament, to safeguard national security and maintain peace (safeguards) international

  7. Prodrug Approach for Increasing Cellular Glutathione Levels

    Directory of Open Access Journals (Sweden)

    Ivana Cacciatore

    2010-03-01

    Full Text Available Reduced glutathione (GSH is the most abundant non-protein thiol in mammalian cells and the preferred substrate for several enzymes in xenobiotic metabolism and antioxidant defense. It plays an important role in many cellular processes, such as cell differentiation, proliferation and apoptosis. GSH deficiency has been observed in aging and in a wide range of pathologies, including neurodegenerative disorders and cystic fibrosis (CF, as well as in several viral infections. Use of GSH as a therapeutic agent is limited because of its unfavorable biochemical and pharmacokinetic properties. Several reports have provided evidence for the use of GSH prodrugs able to replenish intracellular GSH levels. This review discusses different strategies for increasing GSH levels by supplying reversible bioconjugates able to cross the cellular membrane more easily than GSH and to provide a source of thiols for GSH synthesis.

  8. Emerging roles of extracellular vesicles in cellular senescence and aging.

    Science.gov (United States)

    Takasugi, Masaki

    2018-02-01

    Cellular senescence is a cellular program that prevents the proliferation of cells at risk of neoplastic transformation. On the other hand, age-related accumulation of senescent cells promotes aging at least partially due to the senescence-associated secretory phenotype, whereby cells secrete high levels of inflammatory cytokines, chemokines, and matrix metalloproteinases. Emerging evidence, however, indicates that extracellular vesicles (EVs) are important mediators of the effects of senescent cells on their microenvironment. Senescent cells secrete more EphA2 and DNA via EVs, which can promote cancer cell proliferation and inflammation, respectively. Extracellular vesicles secreted from DNA-damaged cells can also affect telomere regulation. Furthermore, it has now become clear that EVs actually play important roles in many aspects of aging. This review is intended to summarize these recent progresses, with emphasis on relationships between cellular senescence and EVs. © 2018 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  9. Changes in ultrastructure, protease and caspase-like activities during flower senescence in Lilium longiflorum.

    Science.gov (United States)

    Battelli, Riccardo; Lombardi, Lara; Rogers, Hilary J; Picciarelli, Piero; Lorenzi, Roberto; Ceccarelli, Nello

    2011-05-01

    The last phase of flower development is senescence during which nutrients are recycled to developing tissues. The ultimate fate of petal cells is cell death. In this study we used the ethylene-insensitive Lilium longiflorum as a model system to characterize Lily flower senescence from the physiological, biochemical and ultrastructural point of view. Lily flower senescence is highly predictable: it starts three days after flower opening, before visible signs of wilting, and ends with the complete wilting of the corolla within 10 days. The earliest events in L. longiflorum senescence include a fall in fresh and dry weight, fragmentation of nuclear DNA and cellular disruption. Mesophyll cell degradation is associated with vacuole permeabilization and rupture. Protein degradation starts later, coincident with the first visible signs of tepal senescence. A fall in total protein is accompanied by a rise in total proteases, and also by a rise of three classes of caspase-like activity with activities against YVAD, DEVD and VEID. The timing of the appearance of these caspase-like activities argues against their involvement in the regulation of the early stages of senescence, but their possible role in the regulation of the final stages of senescence and cell death is discussed. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  10. Amifostine is a potent radioprotector of salivary glands in radioiodine therapy. Structural and ultrastructural findings

    International Nuclear Information System (INIS)

    Kutta, H.; Kampen, U.; Sagowski, C.; Brenner, W.; Bohuslavizki, K.H.; Paulsen, F.

    2005-01-01

    Background and purpose: salivary gland impairment following high-dose radioiodine treatment is well recognized. Since differentiated thyroid cancer has a good prognosis, reduction of long-term side effects is important. This study investigates the radioprotective effects of amifostine in salivary glands of rabbits receiving high-dose radioiodine therapy so as to obtain deeper insight in changes on the cellular and ultrastructural level. Material and methods: a total of 20 rabbits were investigated. High-dose radioiodine therapy applying 1 GBq 131 I was performed in 16 animals. Eight of these 16 animals received 200 mg/m 2 body surface amifostine prior to high-dose radioiodine therapy. Four additional rabbits served as controls, two receiving amifostine, the other two no treatment at all. Subsequently, salivary glands (submandibular and parotid glands, respectively) of all animals were examined by light and transmission electron microscopy. Results: parenchymal damage of both parotid and submandibular glands, specially acinar structures comprising cell organelles and nuclei, of animals pretreated with amifostine was much less pronounced than in animals without amifostine pretreatment. Conclusion: the results indicate that parenchymal damage in salivary glands induced by high-dose radioiodine therapy can significantly be reduced by amifostine. Therefore, amifostine therapy may increase quality of life in patients with differentiated thyroid cancer after radioiodine treatment. (orig.)

  11. [Effects of silicon on the ultrastructures of wheat radical cells under copper stress].

    Science.gov (United States)

    Zhang, Dai-Jing; Ma, Jian-Hui; Yang, Shu-Fang; Chen, Hui-Ting; Liu, Pei; Wang, Wen-Fei; Li, Chun-Xi

    2014-08-01

    To explore the alleviation effect of silicon on wheat growth under copper stress, cultivar Aikang 58 was chosen as the experimental material. The growth, root activities and root tip ultrastructures of wheat seedlings, which were cultured in Hoagland nutrient solution with five different treatments (control, 15 mg x L(-1) Cu2+, 30 mg x L(-1) Cu2+, 15 mg x L(-1) Cu2+ and 50 mg x L(-1) silicon, 30 mg x L(-1) Cu2+ and 50 mg x L(-1) silicon), were fully analyzed. The results showed that root length, plant height and root activities of wheat seedlings were significantly restrained under the copper treatments compared with the control (P effects were alleviated after adding silicon to copper-stress Hoagland nutrient solution. Under copper stress, the cell wall and cell membrane of wheat seedling root tips suffered to varying degrees of destruction, which caused the increase of intercellular space and the disappearance of some organelles. After adding silicon, the cell structure was maintained intact, although some cells and organelles were still slightly deformed compared with the control. In conclusion, exogenous silicon could alleviate the copper stress damages on wheat seedlings and cellular components to some extent.

  12. Ecophysiological, anatomical and ultrastructural characteristics of Vitex polygama Cham. (Verbenaceae submitted to different concentrations of fluoride

    Directory of Open Access Journals (Sweden)

    Zélia Terezinha Teixeira Rossi

    2016-12-01

    Full Text Available Fluorides released during the manufacture of aluminum, fertilizers, glass and ceramics are considered to be highly toxic to plants, causing damages in relatively small concentrations. This study aimed to evaluate fluoride (F accumulation and its effects on Vitex polygama Cham. (Verbenaceae exposed to simulated rain containing potassium fluoride in concentrations of 5, 10, 15 and 20 mg L-1. Vitex polygama presented no visual symptoms of foliar injury and accumulated a relatively small amount of F-, significant only for the treatments with higher concentrations of the pollutant.  F- promoted an increase in non-photochemical quenching (qN and in the coefficient due to non-photochemical extinction (NPQ, which indicates higher dissipation of radiant energy in the heat form. Damages in the chloroplast structure, in cellular membranes and in epicuticular waxes, besides cytoplasm granulation and irregularities in the epidermal cell walls were also detected in plants exposed to the pollutant. The results show a considerable resistance of Vitex polygama to F and reinforce the prognostic value of physiological, anatomical and ultrastructural analysis in the detection of damages caused by the pollutant in the leaf structure of this species.

  13. Morphogenesis of Pestiviruses: New Insights from Ultrastructural Studies of Strain Giraffe-1

    Science.gov (United States)

    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

  14. Morphological and ultrastructural analysis of Turritopsis nutricula during life cycle reversal.

    Science.gov (United States)

    Carla', E C; Pagliara, P; Piraino, S; Boero, F; Dini, L

    2003-06-01

    The hydrozoa life cycle is characterized, in normal conditions, by the alternation of a post-larval benthic polyp and an adult pelagic medusa; however, some species of Hydrozoa react to environmental stress by reverting their life cycle: i.e. an adult medusa goes back to the juvenile stage of polyp. This very uncommon life cycle could be considered as some sort of inverted metamorphosis. A morphological study of different stages during the reverted life cycle of Turritopsis nutricula led to the characterization of four different stages: healthy medusa, unhealthy medusa, four-leaf clover and cyst. The ultrastructural study of the cellular modifications (during the life cycle reversion of T. nutricula) showed the presence of both degenerative and apoptotic processes. Degeneration was prevalent during the unhealthy medusa and four-leaf clover stages, while the apoptotic rate was higher during the healthy medusa and cyst stages. The significant presence of degenerative and apoptotic processes could be related to the occurrence of a sort of metamorphosis when an adult medusa transforms itself into a polyp.

  15. Amifostine is a potent radioprotector of salivary glands in radioiodine therapy. Structural and ultrastructural findings

    Energy Technology Data Exchange (ETDEWEB)

    Kutta, H. [Dept. of Anatomy, Christian Albrecht Univ. of Kiel (Germany); Dept. of Oto-Rhino-Laryngology, Head and Neck Surgery, Univ. Hospital Hamburg-Eppendorf, Hamburg (Germany); Kampen, U. [Clinic of Nuclear Medicine, Christian Albrecht Univ. of Kiel (Germany); Sagowski, C. [Dept. of Oto-Rhino-Laryngology, Head and Neck Surgery, Univ. Hospital Hamburg-Eppendorf, Hamburg (Germany); Brenner, W. [Clinic of Nuclear Medicine, Christian Albrecht Univ. of Kiel (Germany); Dept. of Nuclear Medicine, Univ. Hospital Hamburg-Eppendorf, Hamburg (Germany); Bohuslavizki, K.H. [Nuclear Medicine, Hamburg (Germany); Paulsen, F. [Dept. of Anatomy, Christian Albrecht Univ. of Kiel (Germany); Dept. of Anatomy and Cell Biology, Martin-Luther-Univ. of Halle-Wittenberg, Halle/Saale (Germany)

    2005-04-01

    Background and purpose: salivary gland impairment following high-dose radioiodine treatment is well recognized. Since differentiated thyroid cancer has a good prognosis, reduction of long-term side effects is important. This study investigates the radioprotective effects of amifostine in salivary glands of rabbits receiving high-dose radioiodine therapy so as to obtain deeper insight in changes on the cellular and ultrastructural level. Material and methods: a total of 20 rabbits were investigated. High-dose radioiodine therapy applying 1 GBq {sup 131}I was performed in 16 animals. Eight of these 16 animals received 200 mg/m{sup 2} body surface amifostine prior to high-dose radioiodine therapy. Four additional rabbits served as controls, two receiving amifostine, the other two no treatment at all. Subsequently, salivary glands (submandibular and parotid glands, respectively) of all animals were examined by light and transmission electron microscopy. Results: parenchymal damage of both parotid and submandibular glands, specially acinar structures comprising cell organelles and nuclei, of animals pretreated with amifostine was much less pronounced than in animals without amifostine pretreatment. Conclusion: the results indicate that parenchymal damage in salivary glands induced by high-dose radioiodine therapy can significantly be reduced by amifostine. Therefore, amifostine therapy may increase quality of life in patients with differentiated thyroid cancer after radioiodine treatment. (orig.)

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

    Science.gov (United States)

    Tilinca, Mariana; Florea, Adrian

    2018-01-01

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

  17. Proliferation: myth or reality?; La proliferation: mythe ou realite?

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This article analyzes the proliferation approach, its technical condition and political motivation, and the share between the myth (political deception, assumptions and extrapolations) and the reality of proliferation. Its appreciation is complicated by the irrational behaviour of some political actors and by the significant loss of the non-use taboo. The control of technologies is an important element for proliferation slowing down but an efficient and autonomous intelligence system remains indispensable. (J.S.)

  18. The changing proliferation threat

    Energy Technology Data Exchange (ETDEWEB)

    Sopko, J.F.

    1996-12-31

    Technological advances and new adversaries with new motives have reduced the relevancy and effectiveness of the American nonproliferation strategy that was developed during the Cold War. The Cold War`s end and the breakup of the Soviet Union have created new proliferation dangers even as they have reduced others. The familiar balance of nuclear terror that linked the superpowers and their client states for nearly 50 years in a choreographed series of confrontations has given way to a much less predictable situation, where weapons of unthinkable power appear within the grasp of those more willing to use them. Rogue nations and {open_quotes}clientless{close_quotes} states, terrorist groups, religious cults, ethnic minorities, disaffected political groups, and even individuals appear to have jointed a new arms race toward mass destruction. The author describes recent events that suggest the new trends and a serious challenge to US national security.

  19. The nuclear proliferation

    International Nuclear Information System (INIS)

    Gere, F.

    1995-04-01

    In this book is detailed the beginning of nuclear military power, with the first bomb of Hiroshima, the different ways of getting uranium 235 and plutonium 239, and how the first countries (Usa, Ussr, China, United kingdom, France) got nuclear weapons. Then the most important part is reviewed with the details of non-proliferation treaty and the creation of IAEA to promote civilian nuclear power in the world and to control the use of plutonium and uranium in nuclear power plants. The cases of countries who reached the atom mastery, such Israel, South Africa, Pakistan, Iraq, North Korea, Argentina, Brazil, Iran, Algeria, Taiwan and the reasons which they wanted nuclear weapon for or why they gave up, are exposed

  20. An ultrastructural comparison of mesotheliomas and adenocarcinomas of the ovary and endometrium.

    Science.gov (United States)

    Warhol, M J; Hunter, N J; Corson, J M

    1982-01-01

    The ultrastructural features of 16 malignant mesotheliomas were compared qualitatively and quantitatively with nine ovarian adenocarcinomas and 11 endometrial adenocarcinomas. The mesotheliomas could be distinguished ultrastructurally by their significantly greater content of tonofilaments (p less than 0.001) and their lack of structures found in both ovarian and endometrial adenocarcinomas, specifically abundant mucin, numerous cilia, and dense core granules of the neurosecretory type.

  1. Ultrastructural localization of nonheme celluar iron with ferrocyanide.

    Science.gov (United States)

    Parmley, R T; Spicer, S S; Alvarez, C J

    1978-09-01

    The Prussian blue reaction was evaluated at the ultrastructural level as a cytochemical method to identify ferric and ferrous iron in rat bone marrow and splenic macrophages. Satisfactory tissue preservation and staining were achieved after fixation for 1 hr in 3% glutaraldehyde and exposure for 30 min to Perls's ferrocyanide solution before routine osmication and embedding. The acid ferrocyanide solution formed cuboidal and irregular electron-opaque deposits which localized ferric iron in the macrophage siderosomes and hyaloplasm. When thin sections were directly stained with the acid ferrocyanide, the stain deposits were much less distinct. The size and number of cytes exhibited sparse evenly distributed stain deposits. Several cells displayed abundant precipitates on the inner surface of the plasmalemma. Prussian blue precipitates were occasionally seen in mitochondria and nuclear euchromatin. Although osmium tetroxide post-fixation improved tissue preservation, it did not enhance the density of the ferri-ferrocyanide precipitate. The ferrocyanide solution yielded cuboidal deposits also in clots impregnated with ferritin, and electron diffraction analysis confirmed the symmetrical crystal structure of these stain precipitates. Smaller irregular precipitates were formed in clots impregnated with FeCl3, or Fe2 (SO4)3 solutions, despite the equally interpreted as indicating that the iron hydroxide core or protein structure of ferritin and hemosiderin contributed to the formation of the ultrastructurally evident cuboidal precipitates, but were not necessary for the formation of a colored reaction product. The acid ferrocyanide solution failed to stain clots formed in FeCI2, CuCI2 or CuCI solutions. Staining with a ferricyanide solution identified only sparse foci of ferrous iron in some siderosomes. This study demonstrates that the Prussian blue reaction can be used ultrastructurally to localize iron cations bound to some nonheme iron binding proteins.

  2. 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

  3. 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

  4. Ultrastructural modifications in Common ash tissues colonised by Chalara fraxinea

    Directory of Open Access Journals (Sweden)

    Elisa DAL MASO

    2013-01-01

    Full Text Available Chalara fraxinea, the cause of ash dieback, is present in many European countries and constitutes a severe threat to Fraxinus spp. in forests, urban areas and nurseries. This study investigated tissue colonisation strategies of the parasite in Common ash at ultrastructural level and demonstrated that C. fraxinea develops intracellularly, moving through the cells and easily colonising the phloem, paratracheal parenchyma and parenchymatic rays. However, damage to either the plasmalemma or cell walls was not observed under our experimental conditions. Furthermore, the presence of intrahyphal hyphae was frequently detected, which are likely associated with a regeneration mechanism.

  5. Anatomy and ultrastructure of root nodules of Lupinus luteus

    Directory of Open Access Journals (Sweden)

    A. Woźny

    2015-01-01

    Full Text Available The paper presents anatomic structure of root nodules of lupine (Lupinus luteus L. cv. Express and ultrastructure of cells infected by Rhizobium, The inside of cells from the infected nodule region was filled with numerous bacteria; only centrally located cell nucleus was free of bacteria. Rhizobium was present mostly in the form of "transforming bacteria" (according to the terminology by Ching et al. 1977, characterized by visible nucleoid areas, numerous ribosomes, and polyphosphate granules, although typical bacterioids with poly-β-hydroxybutyrate were also found.

  6. Autofluorescence and ultrastructure in the Myxomycete Diachea leucopodia (Physarales).

    Science.gov (United States)

    Carmarán, Cecilia C; Rosenfeldt, Sonia; Skigin, Diana; Inchaussandague, Marina; Keller, Harold W

    2013-12-01

    Autofluorescence is reported for the first time in Myxomycete fruiting bodies. Ultrastructure of stalked sporangia of Diachea leucopodia (Didymiaceae, Physarales) was studied using scanning and transmission electron microscopy, energy-dispersive X-ray microanalysis, and fluorescence microscopy. External and internal properties of the peridium that surround the spores and capillitium exhibit autofluorescence. The stalk is composed of calcareous granules and energy-dispersive X-ray microanalysis demonstrates that the elemental composition of the peridium, capillitium, and stalk has varying concentrations of calcium.

  7. YAP/TEAD-mediated transcription controls cellular senescence.

    Science.gov (United States)

    Xie, Qi; Chen, Jing; Feng, Han; Peng, Shengyi; Adams, Ursula; Bai, Yujie; Huang, Li; Li, Ji; Huang, Junjian; Meng, Songshu; Yuan, Zengqiang

    2013-06-15

    Transcription coactivator Yes-associated protein (YAP) plays an important role in the regulation of cell proliferation and apoptosis. Here, we identify a new role of YAP in the regulation of cellular senescence. We find that the expression levels of YAP proteins decrease following the replication-induced cellular senescence in IMR90 cells. Silencing of YAP inhibits cell proliferation and induces premature senescence. In additional experiments, we observe that cellular senescence induced by YAP deficiency is TEAD- and Rb/p16/p53-dependent. Furthermore, we show that Cdk6 is a direct downstream target gene of YAP in the regulation of cellular senescence, and the expression of Cdk6 is through the YAP-TEAD complex. Ectopic expression of Cdk6 rescued YAP knockdown-induced senescence. Finally, we find that downregulation of YAP in tumor cells increases senescence in response to chemotherapeutic agents, and YAP or Cdk6 expression rescues cellular senescence. Taken together, our findings define the critical role of YAP in the regulation of cellular senescence and provide a novel insight into a potential chemotherapeutic avenue for tumor suppression. ©2013 AACR.

  8. Epigenetics and Cellular Metabolism

    Directory of Open Access Journals (Sweden)

    Wenyi Xu

    2016-01-01

    Full Text Available Living eukaryotic systems evolve delicate cellular mechanisms for responding to various environmental signals. Among them, epigenetic machinery (DNA methylation, histone modifications, microRNAs, etc. is the hub in transducing external stimuli into transcriptional response. Emerging evidence reveals the concept that epigenetic signatures are essential for the proper maintenance of cellular metabolism. On the other hand, the metabolite, a main environmental input, can also influence the processing of epigenetic memory. Here, we summarize the recent research progress in the epigenetic regulation of cellular metabolism and discuss how the dysfunction of epigenetic machineries influences the development of metabolic disorders such as diabetes and obesity; then, we focus on discussing the notion that manipulating metabolites, the fuel of cell metabolism, can function as a strategy for interfering epigenetic machinery and its related disease progression as well.

  9. Architected Cellular Materials

    Science.gov (United States)

    Schaedler, Tobias A.; Carter, William B.

    2016-07-01

    Additive manufacturing enables fabrication of materials with intricate cellular architecture, whereby progress in 3D printing techniques is increasing the possible configurations of voids and solids ad infinitum. Examples are microlattices with graded porosity and truss structures optimized for specific loading conditions. The cellular architecture determines the mechanical properties and density of these materials and can influence a wide range of other properties, e.g., acoustic, thermal, and biological properties. By combining optimized cellular architectures with high-performance metals and ceramics, several lightweight materials that exhibit strength and stiffness previously unachievable at low densities were recently demonstrated. This review introduces the field of architected materials; summarizes the most common fabrication methods, with an emphasis on additive manufacturing; and discusses recent progress in the development of architected materials. The review also discusses important applications, including lightweight structures, energy absorption, metamaterials, thermal management, and bioscaffolds.

  10. Ultrastructural investigations about the effect of X-rays and quinacrine (Atebrin) - alone or in combination - upon Ehrlich ascitic carcinoma cells in monolayer culture

    Energy Technology Data Exchange (ETDEWEB)

    Pfab, R.; Biller, H.; Hess, F.; Schachtschabel, D.O.; Paul, N.

    1983-08-01

    Already two days after an X-ray irradiation with 8 Gy performed during the phase of exponential growth, the cells of an Ehrlich ascitic carcinoma in monolayer culture showed remarkable ultrastructural modifications, e.g. a markedly vacuolized endoplasmic reticulum, swollen mitochondria, increase of lysosome-like structures, and a decrease of microvilli in number and size. Ehrlich ascitic carcinoma cells submitted to an X-ray irradiation with 8 Gy and subsequently incubated with quinacrine (Atebrin) in a concentration of 4x10/sup -6/ M, which alone had no significant effects on growth or ultrastructure, showed severe cellular lesions. The endoplasmic reticulum was still more vacuolized, the mitochondria were severely damaged, lysosome-like structures and residual bodies were increased, and the cellular surfaces had still less microvilli. Microtubules and microfilaments, however, seemed rather increased. The effects of quinacrine (Atebrin) on cells exposed to X-rays were discussed with respect to the known inhibiting action of this substance on DNA synthesis, especially with regard to DNA reparation. The modifications of the microtubule-microfilament system could be correlated to increased intracellular digestive processes involved in the catabolism of radiodamaged structures.

  11. Cellular redox, cancer and human papillomavirus.

    Science.gov (United States)

    Cruz-Gregorio, Alfredo; Manzo-Merino, Joaquín; Lizano, Marcela

    2018-02-15

    High-risk Human Papillomavirus (HR-HPV) is the causative agent of different human cancers. A persistent HR-HPV infection alters several cellular processes involved in cell proliferation, apoptosis, immune evasion, genomic instability and transformation. Cumulative evidence from past studies indicates that HR-HPV proteins are associated with oxidative stress (OS) and has been proposed as a risk factor for cancer development. Reactive oxygen and nitrogen species (RONS) regulate a plethora of processes inducing cellular proliferation, differentiation and death. Oxidative stress (OS) is generated when an imbalance in the redox state occurs due to deregulation of the oxidant and antioxidant systems, which, in turn, promotes the damage of DNA, proteins and lipids, allowing the accumulation of mutations and genome instability. OS has been associated with the establishment and development of different cancers, and it has recently been proposed as a co-factor in cervical cancer development. This review is focused on evidence regarding the association of OS with HR-HPV proteins, and the interplay of the viral proteins with different elements of the antioxidant and DNA damage response (DDR) systems, emphasizing the processes that might be required for the viral life cycle and viral DNA integration into the host genome, which is a key element in the carcinogenic process induced by HR-HPV. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Chemical Methods to Induce Beta-Cell Proliferation

    Directory of Open Access Journals (Sweden)

    Amedeo Vetere

    2012-01-01

    Full Text Available Pancreatic beta-cell regeneration, for example, by inducing proliferation, remains an important goal in developing effective treatments for diabetes. However, beta cells have mainly been considered quiescent. This “static” view has recently been challenged by observations of relevant physiological conditions in which metabolic stress is compensated by an increase in beta-cell mass. Understanding the molecular mechanisms underlining these process could open the possibility of developing novel small molecules to increase beta-cell mass. Several cellular cell-cycle and signaling proteins provide attractive targets for high throughput screening, and recent advances in cell culture have enabled phenotypic screening for small molecule-induced beta-cell proliferation. We present here an overview of the current trends involving small-molecule approaches to induce beta-cell regeneration by proliferation.

  13. Cell proliferation inhibition in reduced gravity

    Science.gov (United States)

    Moos, P. J.; Fattaey, H. K.; Johnson, T. C.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Extended durations of spaceflight have been shown to be deleterious on an organismic level; however, mechanisms underlying cellular sensitivity to the gravitational environment remain to be elucidated. The majority of the gravitational studies to date indicates that cell regulatory pathways may be influenced by their gravitational environment. Still, few cell biology experiments have been performed in space flight and even fewer experiments have been repeated on subsequent flights. With flight opportunities on STS-50, 54, and 57, Sf9 cells were flown in the BioServe Fluids Processing Apparatus and cell proliferation was measured with and without exposure to a cell regulatory sialoglycopeptide (CeReS) inhibitor. Results from these flights indicate that the Sf9 cells grew comparable to ground controls, that the CeReS inhibitor bound to its specific receptor, and that its signal transduction cascade was not gravity sensitive.

  14. Ultrastructure of the thymus in diabetes mellitus and starvation.

    Science.gov (United States)

    Elmas, Cigdem; Erdogan, Deniz; Take, Gulnur; Ozogul, Candan; Nacar, Ahmet; Koksal, Mete

    2008-01-01

    The purpose of this study was to investigate the ultrastructural change of the thymus under stress conditions created by diabetes accompanied by fasting, and also the effects of insulin therapy. Forty-eight Sprague-Dawley type rats were used in this experiment. Type 1 diabetes symptoms were induced in 24 of the rats by the application of a single dose of intravenous streptozotocin in sodium citrate buffer through the tail vein. A single dose of sodium citrate buffer was given to rats to create a control group. Following the infusions, rats were divided into control, control and fasting, diabetes, diabetes and fasting, and insulin treatment groups. At the end of the experiment tissues from the thymus of the rats were extracted and examined using electron microscopy. Severe degeneration was observed in the prolonged fasting (stress) and diabetes groups without insulin treatment. Insulin treatment was found to mostly reverse this degeneration. This study demonstrates that the thymus was affected ultrastructurally by diabetes and concomitant fasting, and insulin treatment can reverse these changes.

  15. Pseudomembranous oral candidiasis in HIV infection: ultrastructural findings.

    Science.gov (United States)

    Reichart, P A; Philipsen, H P; Schmidt-Westhausen, A; Samaranayake, L P

    1995-07-01

    A light and electron microscopic investigation of pseudomembranous candidiasis in HIV infection was undertaken as there is little data available on the ultrastructural features of the invasive phase of Candida in this disease. On examination of biopsy specimens of four patients, histopathology revealed the classic features of superficial candidiasis, including hyphal penetration down to the spinous cell layer, parakeratosis, acanthosis and spongiosis of the infected, superficial epithelium. However, in one case, hyphae traversed the entire epithelium and crossed the basal membrane, invading the adjacent connective tissue. Ultrastructural investigations revealed initial hyphal penetration through the intercellular spaces, possibly demonstrating thigmotropism. However, hyphal penetration was not solely confined to intercellular spaces, as some specimens demonstrated hyphal elements traversing both the cytoplasm and the nuclei of the spinous cells. In these areas of the epithelium appressoria-like appendages were often found at the hyphal tip. These phenomena, commonly described in plant fungi, have rarely been described in human material. Pools of desmosomes were seen in the vicinity of the hyphal pathways, implying that the penetration procedure is associated with detachment and congregation of desmosomes, possibly by enzymatic means. Interestingly, the host immune response to fungal invasion appeared to be minimal, as no immune-effector cells were seen closely associated with either the blastospores or the hyphae in any of the tissues examined. Whether the foregoing events are exaggerated by the abortive immune response seen in HIV-infected patients, or common in immunocompetent individuals during candidal invasion of epithelia, needs to be ascertained by further studies.

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

    Science.gov (United States)

    Bakhoum, Abdoulaye Jacque; Quilichini, Yann; Miquel, Jordi; Feliu, Carlos; Bâ, Cheikh Tidiane; Marchand, Bernard

    2014-01-01

    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. © A.J. Bakhoum et al., published by EDP Sciences, 2014.

  17. Spermatozoon ultrastructure of Thysanotaenia congolensis (Cyclophyllidea, Anoplocephalidae, Inermicapsiferinae): phylogenetic implications.

    Science.gov (United States)

    Miquel, Jordi; Świderski, Zdzisław; Feliu, Carlos

    2016-08-01

    The mature spermatozoon of Thysanotaenia congolensis, an intestinal parasite of black rat Rattus rattus from Cape Verde, is described by means of transmission electron microscopy. The ultrastructural organization of the sperm cell of T. congolensis follows Levron et al.'s type VII of the Eucestoda. It corresponds to a uniflagellate spermatozoon that presents crested bodies, periaxonemal sheath and intracytoplasmic walls, spiralled cortical microtubules and nucleus spiralled around the axoneme. These characteristics are also present in the spermatozoa of other inermicapsiferines and differ from the characters found in species belonging to the remaining subfamilies of anoplocephalids, namely Anoplocephalinae, Linstowiinae and Thysanosomatinae. Several authors consider the family Anoplocephalidae as a polyphyletic group, and its relationships with the Davaineidae are a matter of controversy. The phylogenetic implications of spermatological ultrastructural features present in inermicapsiferines and in the remaining anoplocephalids are discussed, and the available data on anoplocephalids are compared to similar results in davaineids in order to contribute to a better knowledge of relationships between these cyclophyllidean families.

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

    Directory of Open Access Journals (Sweden)

    Bakhoum Abdoulaye Jacque

    2014-01-01

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

  19. Dietary adaptions in the ultrastructure of dinosaur dentine.

    Science.gov (United States)

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

    2016-12-01

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

  20. Ultrastructural, autoradiographic and electrophoretic examinations of Chara tomentosa spermiogenesis

    Directory of Open Access Journals (Sweden)

    Maria Kwiatkowska

    2014-01-01

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

  1. Ultrastructural study of tissues surrounding replanted teeth and dental implants.

    Science.gov (United States)

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

    2009-03-01

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

  2. 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.

  3. The Ultrastructural Effects of Sulfachloropyrazine on Toxoplasma Gondii Tachyzoites

    Directory of Open Access Journals (Sweden)

    YB Zeng

    2013-03-01

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

  4. The Ultrastructural Effects of Sulfachloropyrazine on Toxoplasma gondii Tachyzoites.

    Science.gov (United States)

    Zeng, Yb; Dong, H; Han, Hy; Jiang, Ll; Zhao, Qp; Zhu, Sh; Ma, Wj; Cheng, J; Huang, B

    2013-01-01

    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. 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). 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. 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.

  5. The New Cellular Immunology

    Science.gov (United States)

    Claman, Henry N.

    1973-01-01

    Discusses the nature of the immune response and traces many of the discoveries that have led to the present state of knowledge in immunology. The new cellular immunology is directing its efforts toward improving health by proper manipulation of the immune mechanisms of the body. (JR)

  6. Electromagnetic cellular interactions.

    Science.gov (United States)

    Cifra, Michal; Fields, Jeremy Z; Farhadi, Ashkan

    2011-05-01

    Chemical and electrical interaction within and between cells is well established. Just the opposite is true about cellular interactions via other physical fields. The most probable candidate for an other form of cellular interaction is the electromagnetic field. We review theories and experiments on how cells can generate and detect electromagnetic fields generally, and if the cell-generated electromagnetic field can mediate cellular interactions. We do not limit here ourselves to specialized electro-excitable cells. Rather we describe physical processes that are of a more general nature and probably present in almost every type of living cell. The spectral range included is broad; from kHz to the visible part of the electromagnetic spectrum. We show that there is a rather large number of theories on how cells can generate and detect electromagnetic fields and discuss experimental evidence on electromagnetic cellular interactions in the modern scientific literature. Although small, it is continuously accumulating. Copyright © 2010 Elsevier Ltd. All rights reserved.

  7. Cyclooxygenases: Proliferation and differentiation | Rastegar ...

    African Journals Online (AJOL)

    ... tissues and is highly inducible by growth factors, cytokines, and tumour promoters. In several studies, the effect of cyclooxygenases on different cell types has been investigated. This review focuses on cyclooxygenases function, cell proliferation and differentiation. Key words: Cyclooxygenases, proliferation, differentiation, ...

  8. Nuclear proliferation: linkages and solutions

    International Nuclear Information System (INIS)

    Quester, G.H.

    1979-01-01

    Nuclear proliferation must be periodically re-examined as a moral as well as a practical foreign policy dilemma. The question is asked whether proliferation precludes a safe and peaceful world, or if a halt to proliferation is adequate without other arms control. The moral dilemma in foreign policy arises over the need to make practical choices which often serve one goal while sacrificing another. The ramifications of nuclear proliferation are examined and the conclusions reached that it is not an acceptable option. It is also decided that, because general disarmament steps will be more difficult to achieve, the world may have to accept a small number of nuclear arsenals as the price of state sovereignties. A high priority for making the effort to prevent proliferation is advised. 8 references

  9. Identification of Predictive Gene Markers for Multipotent Stromal Cell Proliferation.

    Science.gov (United States)

    Bellayr, Ian H; Marklein, Ross A; Lo Surdo, Jessica L; Bauer, Steven R; Puri, Raj K

    2016-06-01

    Multipotent stromal cells (MSCs) are known for their distinctive ability to differentiate into different cell lineages, such as adipocytes, chondrocytes, and osteocytes. They can be isolated from numerous tissue sources, including bone marrow, adipose tissue, skeletal muscle, and others. Because of their differentiation potential and secretion of growth factors, MSCs are believed to have an inherent quality of regeneration and immune suppression. Cellular expansion is necessary to obtain sufficient numbers for use; however, MSCs exhibit a reduced capacity for proliferation and differentiation after several rounds of passaging. In this study, gene markers of MSC proliferation were identified and evaluated for their ability to predict proliferative quality. Microarray data of human bone marrow-derived MSCs were correlated with two proliferation assays. A collection of 24 genes were observed to significantly correlate with both proliferation assays (|r| >0.70) for eight MSC lines at multiple passages. These 24 identified genes were then confirmed using an additional set of MSCs from eight new donors using reverse transcription quantitative polymerase chain reaction (RT-qPCR). The proliferative potential of the second set of MSCs was measured for each donor/passage for confluency fraction, fraction of EdU+ cells, and population doubling time. The second set of MSCs exhibited a greater proliferative potential at passage 4 in comparison to passage 8, which was distinguishable by 15 genes; however, only seven of the genes (BIRC5, CCNA2, CDC20, CDK1, PBK, PLK1, and SPC25) demonstrated significant correlation with MSC proliferation regardless of passage. Our analyses revealed that correlation between gene expression and proliferation was consistently reduced with the inclusion of non-MSC cell lines; therefore, this set of seven genes may be more strongly associated with MSC proliferative quality. Our results pave the way to determine the quality of an MSC population for a

  10. Polyamines and post-irradiation cell proliferation

    International Nuclear Information System (INIS)

    Rosiek, O.; Wronowski, T.; Lerozak, K.; Kopec, M.

    1978-01-01

    The results of three sets of experiments will be presented. Firstly polyamines and DNA content was determined in bone marrow, mesenteric lymph nodes, spleen, liver and kidney of rabbits at the 1, 5, 10 and 20th day after exposure to 600 R of X-irradiation. Polyamine concentration in bone marrow, spleen and lymph nodes was found to be markedly increased during the period of postirradiation recovery. Secondly, effect of 10 -5 M methyl glyoxalbis, guanylhydrazone (MGBG), an inhibitor of spermidine and spermine synthesis, on multiplication of X-irradiated cultures of murine lymphoblaste L5178Y-S was assessed. MGBG-induced inhibition of cell proliferation could be prevented by concurrent administration of 10 -4 M spermidine. Thirdly the influence of putrescine on bone marrow cellularity and 3 H-thymidine incorporation into bone marrow cells was investigated in X-irradiated mice. The results obtained indicate close relation of polyamines to cell proliferation processes after irradiation. (orig./AJ) [de

  11. Intraretinal proliferation induced by retinal detachment

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, S.K.; Erickson, P.A.; Lewis, G.P.; Anderson, D.H. (Univ. of California, Santa Barbara (USA))

    1991-05-01

    Cellular proliferation after retinal detachment was studied by {sup 3}H-thymidine light microscopic autoradiography in cats that had experimental detachments of 0.5-180 days duration. The animals underwent labeling 2 hr before death with an intraocular injection of 200 microCi of {sup 3}H-thymidine. The number of labeled nuclei were counted in 1-micron thick tissue sections in regions of detachment, in regions of the experimental eyes that remained attached, and in control eyes that had no detachments. In the normal eye, in one that had only the lens and vitreous removed, and in the eyes with 0.5- and 1-day detachments, the number of labeled nuclei ranged from 0/mm (0.5-day detachment) to 0.38/mm (lens and vitreous removed only). By 2 days postdetachment, the number of labeled nuclei increased to 2.09/mm. The highest levels of labeling occurred in two animals with detachments of 3 (7.86/mm) and 4 (7.09/mm) days. Thereafter, the numbers declined steadily until near-baseline counts were obtained at 14 days. The number of labeled nuclei was slightly elevated in the attached regions of two animals with 3-day detachments. Labeled cell types included: Mueller cells, astrocytes, pericytes, and endothelial cells of the retinal vasculature, and both resident (microglial cells) and invading macrophages. In an earlier study RPE cells were also shown to proliferate in response to detachment. Thus, these data show that proliferation is a rapid response to detachment, reaching a maximum within 4 days, and that virtually every nonneuronal cell type in the retina can participate in this response. The data suggest that events leading to such clinical manifestations as proliferative vitreoretinopathy and subretinal fibrosis may have their beginnings in this very early proliferative response.

  12. Intraretinal proliferation induced by retinal detachment

    International Nuclear Information System (INIS)

    Fisher, S.K.; Erickson, P.A.; Lewis, G.P.; Anderson, D.H.

    1991-01-01

    Cellular proliferation after retinal detachment was studied by 3 H-thymidine light microscopic autoradiography in cats that had experimental detachments of 0.5-180 days duration. The animals underwent labeling 2 hr before death with an intraocular injection of 200 microCi of 3 H-thymidine. The number of labeled nuclei were counted in 1-micron thick tissue sections in regions of detachment, in regions of the experimental eyes that remained attached, and in control eyes that had no detachments. In the normal eye, in one that had only the lens and vitreous removed, and in the eyes with 0.5- and 1-day detachments, the number of labeled nuclei ranged from 0/mm (0.5-day detachment) to 0.38/mm (lens and vitreous removed only). By 2 days postdetachment, the number of labeled nuclei increased to 2.09/mm. The highest levels of labeling occurred in two animals with detachments of 3 (7.86/mm) and 4 (7.09/mm) days. Thereafter, the numbers declined steadily until near-baseline counts were obtained at 14 days. The number of labeled nuclei was slightly elevated in the attached regions of two animals with 3-day detachments. Labeled cell types included: Mueller cells, astrocytes, pericytes, and endothelial cells of the retinal vasculature, and both resident (microglial cells) and invading macrophages. In an earlier study RPE cells were also shown to proliferate in response to detachment. Thus, these data show that proliferation is a rapid response to detachment, reaching a maximum within 4 days, and that virtually every nonneuronal cell type in the retina can participate in this response. The data suggest that events leading to such clinical manifestations as proliferative vitreoretinopathy and subretinal fibrosis may have their beginnings in this very early proliferative response

  13. Estradiol and corticosterone stimulate the proliferation of a GH cell line, MtT/S: Proliferation of growth hormone cells.

    Science.gov (United States)

    Nogami, Haruo; Hiraoka, Yoshiki; Aiso, Sadakazu

    2016-08-01

    Estrogens are known as a potent growth-stimulator of the anterior pituitary cells such as prolactin cells and somatomammotroph cell lines, while glucocorticoids often inhibit cellular proliferation in the pituitary gland as well as in the extra-pituitary tissues. In this study, the involvement of these steroid hormones in the regulation of proliferation was examined in the MtT/S cells, secreting growth hormone (GH). Effects of estrogens and glucocorticoids were examined in MtT/S cells grown in the medium containing dextran-coated charcoal treated serum. The relative cell density after culture was estimated by the Cell Titer-Glo Luminescent Cell Viability Assay System, and the proliferation rate was determined by the BrdU incorporation method. The mRNA levels were determined by real-time PCR. Estradiol and the specific agonist for both estrogen receptor (ER) α and ERβ stimulated MtT/S growth at a dose dependent manner. The membrane impermeable estrogen, 17β-estradiol-bovine serum albumin conjugate also stimulated the MtT/S proliferation. The effects of all estrogens were inhibited by an estrogen receptor antagonist, ICI182780. Corticosterone stimulated the proliferation of MtT/S cells at doses lower than 10nM without stimulating GH gene transcription, whereas it did not change the proliferation rate at 1μM. The effects of corticosterone were inhibited by glucocorticoid receptor inhibitor, RU486, but not by the mineralocorticoid receptor antagonist, spironolactone. Both estrogens and glucocorticoids were found to stimulate the proliferation of MtT/S, increasing the mRNA expression of cyclins D1, D3, and E. The results suggest that estrogens and glucocorticoids may be involved in the mechanisms responsible for the proliferation of GH cells in the course of pituitary development, to maintain the population of GH cells in the adult pituitary gland, and also in the promotion of GH cell tumors. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Cellularized Bilayer Pullulan-Gelatin Hydrogel for Skin Regeneration.

    Science.gov (United States)

    Nicholas, Mathew N; Jeschke, Marc G; Amini-Nik, Saeid

    2016-05-01

    Skin substitutes significantly reduce the morbidity and mortality of patients with burn injuries and chronic wounds. However, current skin substitutes have disadvantages related to high costs and inadequate skin regeneration due to highly inflammatory wounds. Thus, new skin substitutes are needed. By combining two polymers, pullulan, an inexpensive polysaccharide with antioxidant properties, and gelatin, a derivative of collagen with high water absorbency, we created a novel inexpensive hydrogel-named PG-1 for "pullulan-gelatin first generation hydrogel"-suitable for skin substitutes. After incorporating human fibroblasts and keratinocytes onto PG-1 using centrifugation over 5 days, we created a cellularized bilayer skin substitute. Cellularized PG-1 was compared to acellular PG-1 and no hydrogel (control) in vivo in a mouse excisional skin biopsy model using newly developed dome inserts to house the skin substitutes and prevent mouse skin contraction during wound healing. PG-1 had an average pore size of 61.69 μm with an ideal elastic modulus, swelling behavior, and biodegradability for use as a hydrogel for skin substitutes. Excellent skin cell viability, proliferation, differentiation, and morphology were visualized through live/dead assays, 5-bromo-2'-deoxyuridine proliferation assays, and confocal microscopy. Trichrome and immunohistochemical staining of excisional wounds treated with the cellularized skin substitute revealed thicker newly formed skin with a higher proportion of actively proliferating cells and incorporation of human cells compared to acellular PG-1 or control. Excisional wounds treated with acellular or cellularized hydrogels showed significantly less macrophage infiltration and increased angiogenesis 14 days post skin biopsy compared to control. These results show that PG-1 has ideal mechanical characteristics and allows ideal cellular characteristics. In vivo evidence suggests that cellularized PG-1 promotes skin regeneration and may

  15. HDACi: cellular effects, opportunities for restorative dentistry.

    LENUS (Irish Health Repository)

    Duncan, H F

    2011-12-01

    Acetylation of histone and non-histone proteins alters gene expression and induces a host of cellular effects. The acetylation process is homeostatically balanced by two groups of cellular enzymes, histone acetyltransferases (HATs) and histone deacetylases (HDACs). HAT activity relaxes the structure of the human chromatin, rendering it transcriptionally active, thereby increasing gene expression. In contrast, HDAC activity leads to gene silencing. The enzymatic balance can be \\'tipped\\' by histone deacetylase inhibitors (HDACi), leading to an accumulation of acetylated proteins, which subsequently modify cellular processes including stem cell differentiation, cell cycle, apoptosis, gene expression, and angiogenesis. There is a variety of natural and synthetic HDACi available, and their pleiotropic effects have contributed to diverse clinical applications, not only in cancer but also in non-cancer areas, such as chronic inflammatory disease, bone engineering, and neurodegenerative disease. Indeed, it appears that HDACi-modulated effects may differ between \\'normal\\' and transformed cells, particularly with regard to reactive oxygen species accumulation, apoptosis, proliferation, and cell cycle arrest. The potential beneficial effects of HDACi for health, resulting from their ability to regulate global gene expression by epigenetic modification of DNA-associated proteins, also offer potential for application within restorative dentistry, where they may promote dental tissue regeneration following pulpal damage.

  16. Radiopharmaceutical cellular uptake mechanisms

    International Nuclear Information System (INIS)

    Stefanescu, Cipriana; Rusu, V.

    1996-01-01

    Cellular radiopharmaceutical specificity depends mainly of the uptake mechanisms. Usually, this can be one of the classical membrane transport type (a passive or active transport, a receptor mediated one or a combination of them). It can also be an electrochemical gradient dependent membrane transport in relation with Nernst equation, as in case of 99m Tc MIBI, the representative molecule of a widely studied family tracers, with applications in cardiac and oncological scintigraphy. Another mechanism can be an ATP dependent active transport, that results in the most important 201 Tl inflow. 201 Tl inflow is also an example of multiple mechanisms involved in cellular ionic inflow. Over 30% of 201 Tl transport imply other ways, like Na + - K + - Cl - co-transport. For a given tracer, the mechanism may depend also on the cell type. In conclusion, knowledge of the radiotracer uptake mechanisms allows finding the 'ideal' radiotracer with high specificity for the tissue to be visualized. (authors)

  17. Molecular and Cellular Signaling

    CERN Document Server

    Beckerman, Martin

    2005-01-01

    A small number of signaling pathways, no more than a dozen or so, form a control layer that is responsible for all signaling in and between cells of the human body. The signaling proteins belonging to the control layer determine what kinds of cells are made during development and how they function during adult life. Malfunctions in the proteins belonging to the control layer are responsible for a host of human diseases ranging from neurological disorders to cancers. Most drugs target components in the control layer, and difficulties in drug design are intimately related to the architecture of the control layer. Molecular and Cellular Signaling provides an introduction to molecular and cellular signaling in biological systems with an emphasis on the underlying physical principles. The text is aimed at upper-level undergraduates, graduate students and individuals in medicine and pharmacology interested in broadening their understanding of how cells regulate and coordinate their core activities and how diseases ...

  18. Nested cellular automata

    International Nuclear Information System (INIS)

    Quasthoff, U.

    1985-07-01

    Cellular automata by definition consist of a finite or infinite number of cells, say of unit length, with each cell having the same transition function. These cells are usually considered as the smallest elements and so the space filled with these cells becomes discrete. Nevertheless, large pictures created by such cellular automata look very fractal. So we try to replace each cell by a couple of smaller cells, which have the same transition functions as the large ones. There are automata where this replacement does not destroy the macroscopic structure. In these cases this nesting process can be iterated. The paper contains large classes of automata with the above properties. In the case of one dimensional automata with two states and next neighbour interaction and a nesting function of the same type a complete classification is given. (author)

  19. Pulsed feedback defers cellular differentiation.

    Directory of Open Access Journals (Sweden)

    Joe H Levine

    2012-01-01

    Full Text Available Environmental signals induce diverse cellular differentiation programs. In certain systems, cells defer differentiation for extended time periods after the signal appears, proliferating through multiple rounds of cell division before committing to a new fate. How can cells set a deferral time much longer than the cell cycle? Here we study Bacillus subtilis cells that respond to sudden nutrient limitation with multiple rounds of growth and division before differentiating into spores. A well-characterized genetic circuit controls the concentration and phosphorylation of the master regulator Spo0A, which rises to a critical concentration to initiate sporulation. However, it remains unclear how this circuit enables cells to defer sporulation for multiple cell cycles. Using quantitative time-lapse fluorescence microscopy of Spo0A dynamics in individual cells, we observed pulses of Spo0A phosphorylation at a characteristic cell cycle phase. Pulse amplitudes grew systematically and cell-autonomously over multiple cell cycles leading up to sporulation. This pulse growth required a key positive feedback loop involving the sporulation kinases, without which the deferral of sporulation became ultrasensitive to kinase expression. Thus, deferral is controlled by a pulsed positive feedback loop in which kinase expression is activated by pulses of Spo0A phosphorylation. This pulsed positive feedback architecture provides a more robust mechanism for setting deferral times than constitutive kinase expression. Finally, using mathematical modeling, we show how pulsing and time delays together enable "polyphasic" positive feedback, in which different parts of a feedback loop are active at different times. Polyphasic feedback can enable more accurate tuning of long deferral times. Together, these results suggest that Bacillus subtilis uses a pulsed positive feedback loop to implement a "timer" that operates over timescales much longer than a cell cycle.

  20. Ultrastructure of human oocytes after in vitro maturation.

    Science.gov (United States)

    Coticchio, Giovanni; Dal Canto, Mariabeatrice; Fadini, Rubens; Mignini Renzini, Mario; Guglielmo, Maria Cristina; Miglietta, Selenia; Palmerini, Maria Grazia; Macchiarelli, Guido; Nottola, Stefania Annarita

    2016-02-01

    How does the ultrastructure of human oocytes matured in vitro compare with oocytes collected from women after full hormonal stimulation? The ultrastructure of human oocytes matured in vitro is largely, but not entirely, similar to those matured in vivo. Embryos derived from in vitro-matured oocytes often have limited developmental potential, possibly as an effect of inappropriate in vitro maturation (IVM) conditions. Transmission electron microscopy (TEM) is a valuable research tool to compare in vivo and in vitro matured oocytes. However, previous studies on the ultrastructure of human IVM oocytes were done with inadequate material or inappropriate IVM conditions, and have limited significance. Immature cumulus cell-enclosed oocytes, retrieved from mid-sized antral follicles of women requiring IVM treatment, were matured in vitro for 30 h. No leftover germinal vesicle-stage oocytes collected from fully stimulated cycles were used. Control in vivo matured oocytes were obtained from age-matched women undergoing full ovarian stimulation. In vitro and in vivo matured oocytes were analysed by TEM and compared according to previously established morphometric criteria of oocyte quality. All oocytes had normal ooplasm showing uniform distribution of organelles. Mitochondrial morphology appeared similar between the maturation conditions. Cortical granules were found typically stratified in a single, mostly continuous row just beneath the ooplasm in all oocytes. Microvilli were well preserved after IVM. Vacuoles were only occasionally found in all oocytes and, if present, they were frequently associated with lysosomes. Mitochondria-smooth endoplasmic reticulum (M-SER) aggregates and mitochondria-vesicles (MV) complexes were commonly found in in vivo matured oocytes. However, large MV complexes partially replaced M-SER aggregates in IVM oocytes. As a note of caution it should be noticed that, being laborious and technically demanding, TEM cannot be applied to a large number

  1. [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

  2. Radiolabeled cellular blood elements

    International Nuclear Information System (INIS)

    Thakur, M.L.; Ezikowitz, M.D.; Hardeman, M.R.

    1985-01-01

    This book contains papers delivered by guest lectures and participants at the Advanced Study Institute's colloquium on Radiolabeled Cellular Blood Elements at Maratea, Italy on August 29, to September 9, 1982. The book includes chapters on basic cell physiology and critical reviews of data and experience in the preparation and use of radiolabeled cells, as well as reports on very recent developments, from a faculty that included experts on cell physiology in health and disease and on the technology of in vivo labeling

  3. Tissue organization and cell ultrastructure in the roots of three Arabidopsis species grown at different zinc concentrations

    Directory of Open Access Journals (Sweden)

    M. Čiamporová

    2015-05-01

    Full Text Available The model plant Arabidopsis thaliana is known to be heavy metal-sensitive in contrast to its relative species A. arenosa and A. halleri classified as pseudometallophytes. Quantitative differences in primary root anatomy previously found between A. thaliana and the non-metallicolous (NM and metallicolous (M populations of the non-model Arabidopsis species necessitated further research at cellular and ultrastructural levels. Seedlings of A. thaliana, ecotype Columbia and a natural population Ratkovo, the NM and M populations of A. arenosa and A. halleri were grown on agar medium containing 10 μM (control and 1000 μM Zn2+ for 5 days. Light microscopy confirmed the higher number of cells in the endodermal, cortical and epidermal layers and a higher incidence of additional cell tiers, the so-called middle cortex (MC in the tolerant genotypes. Such differences were present in untreated plants and even more pronounced in plants exposed to excess of zinc (Zn. Electron microscopy of the root tissues at comparable distances from the root tip showed Casparian bands only in the radial cell walls of endodermis of A. halleri M population originating from severely (Cu, Cd and Pb contaminated site. Casparian bands were not differentiated yet in the roots of the other species and populations, and they were not formed in the cell walls between endodermis and MC cells. In the apical cytoplasm of trichoblast bulges, autophagic vacuoles were found only in the sensitive A. thaliana and small vacuoles in the other genotypes. The enhanced concentration of Zn confirmed the higher metal sensitivity of the model species and did not substantially disturb the root cell ultrastructure of the tolerant Arabidopsis species.

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

    Science.gov (United States)

    Moore, R.

    1990-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Lenarczyk Joanna

    2016-07-01

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

  6. Wavefront cellular learning automata

    Science.gov (United States)

    Moradabadi, Behnaz; Meybodi, Mohammad Reza

    2018-02-01

    This paper proposes a new cellular learning automaton, called a wavefront cellular learning automaton (WCLA). The proposed WCLA has a set of learning automata mapped to a connected structure and uses this structure to propagate the state changes of the learning automata over the structure using waves. In the WCLA, after one learning automaton chooses its action, if this chosen action is different from the previous action, it can send a wave to its neighbors and activate them. Each neighbor receiving the wave is activated and must choose a new action. This structure for the WCLA is necessary in many dynamic areas such as social networks, computer networks, grid computing, and web mining. In this paper, we introduce the WCLA framework as an optimization tool with diffusion capability, study its behavior over time using ordinary differential equation solutions, and present its accuracy using expediency analysis. To show the superiority of the proposed WCLA, we compare the proposed method with some other types of cellular learning automata using two benchmark problems.

  7. Nuclear non proliferation and disarmament

    International Nuclear Information System (INIS)

    2000-01-01

    In the framework of the publication of a document on the ''weapons mastership, disarmament and non proliferation: the french action'', by the ministry of Foreign Affairs and the ministry of Defense, the French Documentation organization presents a whole document. This document describes and details the following topics: the conference on the treaty of non proliferation of nuclear weapons, the France, Usa and Non Governmental Organizations position, the threats of the proliferation, the french actions towards the disarmament, the disarmament in the world, a chronology and some bibliographic resources. (A.L.B.)

  8. Induction of proliferation in vitro of resting human natural killer cells

    International Nuclear Information System (INIS)

    London, L.

    1986-01-01

    Experiments examined the cellular and humoral factors necessary to induce proliferation of purified NK cells in vitro and analyzed the phenotypic characteristics of these proliferating cells. The authors experiments demonstrated that NK cells do not proliferate in response to typical T cell mitogens or to allogeneic stimulation. However, NK cells are readily induced to proliferate in response to either natural or recombinant IL-2. The proliferative response of NK cells to IL-2 is enhanced in the presence of irradiated B lymphoblastoid ell lines. Proliferating NK cells maintain the expression of surface markers characteristic of freshly isolated NK cells which newly expressing surface activation antigens including the IL-2 and transferric receptors and the HLA-DR antigen. The majority of NK cells initiate proliferation in response to IL-2. Greater than 50 U/ml of IL-2 is necessary to induce maximal tritiated thymidine ( 3 H-TdR) incorporation by NK cells, and the interaction of IL-2 with the Tac IL-2 receptor is required for the maintenance of NK cell proliferation. NK cells do not proliferate in response to irradiated Daudi cells alone, which, in the presence of IL-2, may act by maintaining continuous proliferation of the cells originally responsive to IL-2. Unlike NK cells, the authors have shown that only a minor subset of T cells proliferate in response to IL-2 alone

  9. Environment Aware Cellular Networks

    KAUST Repository

    Ghazzai, Hakim

    2015-02-01

    The unprecedented rise of mobile user demand over the years have led to an enormous growth of the energy consumption of wireless networks as well as the greenhouse gas emissions which are estimated currently to be around 70 million tons per year. This significant growth of energy consumption impels network companies to pay huge bills which represent around half of their operating expenditures. Therefore, many service providers, including mobile operators, are looking for new and modern green solutions to help reduce their expenses as well as the level of their CO2 emissions. Base stations are the most power greedy element in cellular networks: they drain around 80% of the total network energy consumption even during low traffic periods. Thus, there is a growing need to develop more energy-efficient techniques to enhance the green performance of future 4G/5G cellular networks. Due to the problem of traffic load fluctuations in cellular networks during different periods of the day and between different areas (shopping or business districts and residential areas), the base station sleeping strategy has been one of the main popular research topics in green communications. In this presentation, we present several practical green techniques that provide significant gains for mobile operators. Indeed, combined with the base station sleeping strategy, these techniques achieve not only a minimization of the fossil fuel consumption but also an enhancement of mobile operator profits. We start with an optimized cell planning method that considers varying spatial and temporal user densities. We then use the optimal transport theory in order to define the cell boundaries such that the network total transmit power is reduced. Afterwards, we exploit the features of the modern electrical grid, the smart grid, as a new tool of power management for cellular networks and we optimize the energy procurement from multiple energy retailers characterized by different prices and pollutant

  10. Ultrastructure of extrusomes in hypotrichous ciliate Pseudourostyla nova

    Science.gov (United States)

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

    2011-01-01

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

  11. Changes in the ultrastructure of rectum cancer cells after irradiation

    International Nuclear Information System (INIS)

    Zaretskaya, A.I.; Lushnikov, E.F.

    1980-01-01

    Data on electron microscopy of the tumoral tissue of 10 patients with rectum cancer after preoperative irradiation in a total focal dose of 2O00 rad are presented. Visually cells with a certain degree of damage of the organoids prevailed in the newgrowths. No relationship between the extent of the tumour differentiation, time of investigation and the nature of radiation changes on the tumoral cells was established. Under the effect of irradiation the cell nucleus size increases and chromatin becomes condensed near the nuclear membrane. Mitocehondria swell and vacuolize. Endoplasmatic reticulum and Golgi complex widen and vacuolize. It is suggested that at the level of ultrastructures there occures the formation of the routes of the development of events: survival of the cell or its destruction by an interphasal or reproductive type

  12. Collagenous Tissues upon Lithium Treatment: A Quantitative Ultrastructural Study

    Directory of Open Access Journals (Sweden)

    Margaret Tzaphlidou

    2004-01-01

    Full Text Available In this review, the influence of lithium treatment in mouse, rat, and rabbit skin, liver, bone, and aorta, as well as arachnoid and dura mater collagen fibrils, is examined using electron microscopy and image processing. Structural changes (fibril architecture and diameter are detected at the ultrastructural level in specimens from all lithium-treated tissues. The overall collagen fibril architecture is disturbed as compared with specimens from normal species. The mean diameter values of treated collagen fibrils are significantly smaller than those from controls in all tissues examined. The banding patterns of fibrils are normal in all cases. Measurements by a computerized method of measuring axial periodicity of fibrils indicate no effect of lithium on this parameter. Computer analysis shows no differences in charged amino acid composition between lithium-treated and -untreated samples. Under the present experimental conditions, lithium can induce permanent structural collagen alterations.

  13. 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.

  14. 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......, 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...... their reduced capacity. The higher number of mitochondria in large pre- and postpubertal oocytes could have an influence on oocyte competence, by increasing the pool of mitochondria available for early embryonic development....

  15. 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.

  16. The ultrastructural localization of von Willebrand factor in endothelial cells.

    Science.gov (United States)

    Warhol, M J; Sweet, J M

    1984-11-01

    Factor VIII-related antigen was localized ultrastructurally in a variety of human tissues (smooth muscle, skeletal muscle, breast, capillary hemangioma) with the use of a low-temperature embedding protein A-gold technique with both polyclonal and monoclonal antisera directed against von Willebrand factor. All endothelial cells examined localized the anti-von Willebrand factor to Weibel-Palade bodies. Cisternae of the endoplasmic reticulum, and cytoplasmic vacuoles were also labeled. These results establish the distribution of factor VIII-related antigen at the subcellular level. The observed distribution suggests that the endothelial cells synthesize von Willebrand factor, store it in Weibel-Palade bodies, and release it by exocytosis. These observations provide in vivo confirmation for previous biochemical and immunocytochemical data obtained from studies on cultured endothelial cells.

  17. [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.

  18. Ultrastructure of Procamallanus (Spirocamallanus) halitrophus (Nematoda: Camallanidae) parasite of flounder.

    Science.gov (United States)

    Cárdenas, M Q; De Souza, W; Lanfredi, R M

    2005-12-01

    The ultrastructure of the camallanid nematode Procamallanus (Spirocamallanus) halitrophus, a parasite of flounder, is described for the first time by the use of transmission electron microscopy. The body wall is composed of an outer cuticle, a hypodermis, and a muscular layer. The cuticle comprises the epicuticle, the cortical, median, fibrous, and basal layers. The cortical layer is subdivided into an outer zone and an inner zone; the median layer is subdivided into an outer layer, rich in electrondense fibrils, and an inner layer, which does not contain these fibrils; the fibrous layer is subdivided into three regions delimited by electrondense lines; the basal layer presents electrondense sustaining structures. Underlying the basal layer is the hypodermis where many organelles are observed. The musculature is striated, and each muscle cell consists of individualized contractile and non-contractile regions. Inclusion bodies are present in the muscle fibers, hypodermis, hypodermal chord, and in the intestine.

  19. Ultrastructural and Histochemical Characterization of the Zebra Mussel Adhesive Apparatus

    Science.gov (United States)

    Farsad, Nikrooz

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

  20. 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...

  1. Soybean genotypic difference in growth, nutrient accumulation and ultrastructure in response to manganese and iron supply in solution culture.

    Science.gov (United States)

    Izaguirre-Mayoral, M L; Sinclair, T R

    2005-07-01

    The objective of this research was to characterize the physiology and cell ultrastructure of two soybean genotypes subjected to nutrient solutions with increasing concentrations of manganese (Mn) at two contrasting iron (Fe) concentrations. Genotypes 'PI227557' and 'Biloxi' were selected based on their distinctly different capacities to accumulate Mn and Fe. * Bradyrhizobium-inoculated plants were grown in hydroponic cultures in a greenhouse. Nutrient solutions were supplied with Mn concentrations ranging from 0.3 to 90 microm, at either 5 or 150 microm Fe as FeEDTA. * For both genotypes and at both Fe concentrations, Mn concentrations from 6.6 to 50 microm did not affect shoot, root and nodule mass, or leaf and nodule ureide concentration. Mn concentrations of 70 and 90 microm did not result in visible toxicity symptoms, but hindered growth and nodulation of 'Biloxi'. An Mn concentration of 0.3 microm was, however, deleterious to growth and nodulation for both genotypes, and caused an accumulation of ureides in leaves and major alterations in the ultrastructure of chloroplasts, nuclei and mitochondria, regardless of the Fe concentration. In 'PI227557', there was also a proliferation of Golgi apparatus and endoplasmic reticulum in the cytoplasm of leaf cells, and nodules showed disrupted symbiosomes lacking poly-beta-hydroxybutirate grains concomitantly with a proliferation of endoplasmic reticulum as well as arrested bacterial division. At 15 microm Fe, ferritin-like crystals were formed in the lumen of chloroplasts of 'PI227557' plants. For both genotypes, there was an antagonism between the Fe and Mn concentrations in leaves, the higher values of both microelements being detected in 'PI227557'. The absence of any detectable relationship between Fe or Mn and zinc, phosphorus and copper concentrations in leaves ruled out those micronutrients as relevant for Mn and Fe nutrition in soybeans. * The results confirmed the greater capacity of 'PI227557' for Mn and Fe

  2. Ultrastructure of oogenesis in the bluefin tuna, Thunnus thynnus.

    Science.gov (United States)

    Abascal, Francisco J; Medina, Antonio

    2005-05-01

    Ovarian ultrastructure of the Atlantic bluefin tuna (Thunnus thynnus) was investigated during the reproductive season with the aim of improving our understanding of the reproductive biology in this species. The bluefin, like the other tunas, has an asynchronous mode of ovarian development; therefore, all developmental stages of the oocyte can be found in mature ovaries. The process of oocyte development can be divided into five distinct stages (formation of oocytes from oogonia, primary growth, lipid stage, vitellogenesis, and maturation). Although histological and ultrastructural features of most these stages are similar among all studied teleosts, the transitional period between primary growth and vitellogenesis exhibits interspecific morphological differences that depend on the egg physiology. Although the most remarkable feature of this stage in many teleosts is the occurrence of cortical alveoli, in the bluefin tuna, as is common in marine fishes, the predominant cytoplasmic inclusions are lipid droplets. Nests of early meiotic oocytes derive from the germinal epithelium that borders the ovarian lumen. Each oocyte in the nest becomes surrounded by extensions of prefollicle cells derived from somatic epithelial cells and these form the follicle that is located in the stromal tissue. The primary growth stage is characterized by intense RNA synthesis and the differentiation of the vitelline envelope. Secondary growth commences 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. 2004 Wiley-Liss, Inc.

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

    Science.gov (United States)

    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.

  4. Grappling archaea: ultrastructural analyses of an uncultivated, cold-loving archaeon and its biofilm

    Directory of Open Access Journals (Sweden)

    Alexandra ePerras

    2014-08-01

    Full Text Available Similarly to Bacteria, Archaea are microorganisms that interact with their surrounding environment in a versatile manner. To date, interactions based on cellular structure and surface appendages have mainly been documented using model systems of cultivable archaea under laboratory conditions. Here, we report on the microbial interactions and ultrastructural features of the uncultivated SM1 Euryarchaeon, which is highly dominant in its biotope. Therefore, biofilm samples taken from the Sippenauer Moor, Germany, were investigated via transmission electron microscopy (TEM; negative staining, thin-sectioning and scanning electron microscopy (SEM in order to elucidate the fine structures of the microbial cells and the biofilm itself. The biofilm consisted of small archaeal cocci (0.6 µm diameter, arranged in a regular pattern (1.2-2.0 µm distance from cell to cell, whereas each archaeon was connected to 6 other archaea on average. Extracellular polymeric substances (EPS were limited to the close vicinity of the archaeal cells, and specific cell surface appendages (hami, Moissl et al., 2005 protruded beyond the EPS matrix enabling microbial interaction by cell-cell contacts among the archaea and between archaea and bacteria. All analyzed hami revealed their previously described architecture of nano-grappling hooks and barb-wire basal structures. Considering the archaeal cell walls, the SM1 Euryarchaea exhibited a double-membrane, which has rarely been reported for members of this phylogenetic domain. Based on these findings, the current generalized picture on archaeal cell walls needs to be revisited, as archaeal cell structures are more complex and sophisticated than previously assumed, particularly when looking into the uncultivated majority.

  5. LYSOSOMAL AND ULTRASTRUCTURAL CHANGES IN HUMAN "TOXIC" NEUTROPHILS DURING BACTERIAL INFECTION

    Science.gov (United States)

    McCall, Charles E.; Katayama, Isao; Cotran, Ramzi S.; Finland, Maxwell

    1969-01-01

    "Toxic" neutrophils from humans with severe bacterial infections, identified by the presence of Döhle bodies, "toxic" granules, and vacuoles were shown to differ from normal neutrophils both in ultrastructure and in lysosome activity. Döhle bodies were identified as lamellar aggregates of rough endoplasmic reticulum. Toxic granules corresponded to the azurophilic granules usually identified by Romanowsky stains only in neutrophil precursors. By electron microscopy such granules were large, electron-dense, and peroxidase positive; they could usually be distinguished from the smaller, less dense, "specific" granules also present in control neutrophils, but in the latter they became visible by light microscopy only after prolonged staining or following fixation with glutaraldehyde. These observations suggest that toxic granules represent an abnormal staining reaction of the large dense granules in the toxic cells, and not phagocytized material, newly formed abnormal granules or autophagic bodies. Alkaline phosphatase activity was significantly greater in toxic neutrophils than in normal ones; 80% of the activity of both was located in the lysosome fraction. Beta glucuronidase was normal. Total acid phosphatase was normal, but the percentage located in the nonlysosome fraction of toxic neutrophils was increased, suggesting that lysosomes were "labilized." Formation of neutral red vacuoles in supravitally stained preparations, an index of lysosome activity, occurred more rapidly in toxic neutrophils. This reaction paralleled degranulation and the formation of clear vacuoles in unstained wet mounts and could be blocked by colchicine, a lysosome stabilizer, or enhanced by procedures which activate lysosomes. "Autophagic" vacuoles were observed by electron microscopy in some toxic neutrophils. These observations are discussed in relation to the concept that the "toxic" neutrophils in severe bacterial infection reflect cellular immaturity and/or stimulation or

  6. 3D-ultrastructure, functions and stress responses of gastropod (Biomphalaria glabrata rhogocytes.

    Directory of Open Access Journals (Sweden)

    Maria Kokkinopoulou

    Full Text Available Rhogocytes are pore cells scattered among the connective tissue of different body parts of gastropods and other molluscs, with great variation in their number, shape and size. They are enveloped by a lamina of extracellular matrix. Their most characteristic feature is the "slit apparatus", local invaginations of the plasma membrane bridged by cytoplasmic bars, forming slits of ca. 20 nm width. A slit diaphragm creates a molecular sieve with permeation holes of 20×20 nm. In blue-blooded gastropods, rhogocytes synthesize and secrete the respiratory protein hemocyanin, and it has been proposed-though not proven-that in the rare red-blooded snail species they might synthesize and secrete the hemoglobin. However, the cellular secretion pathway for respiratory proteins, and the functional role(s of the enigmatic rhogocyte slit apparatus are still unclear. Additional functions for rhogocytes have been proposed, notably a role in protein uptake and degradation, and in heavy metal detoxification. Here we provide new structural and functional information on the rhogocytes of the red-blooded freshwater snail Biomphalaria glabrata. By in situ hybridization of mantle tissues, we prove that rhogocytes indeed synthesize hemoglobin. By electron tomography, the first three dimensional (3D reconstructions of the slit apparatus are provided, showing detail of highly dense material in the cytoplasmic bars close to the slits. By immunogold labelling, we collected evidence that a major component of this material is actin. By genome databank mining, the complete sequence of a B. glabrata nephrin was obtained, and localized to the rhogocytes by immunofluorescence microscopy. The presence of both proteins fit the ultrastructure-based hypothesis that rhogocytes are related to mammalian podocytes and insect nephrocytes. Reactions of the rhogocytes to deprivation of food and cadmium toxification are also documented, and a possible secretion pathway of newly synthesized

  7. 3D-ultrastructure, functions and stress responses of gastropod (Biomphalaria glabrata) rhogocytes.

    Science.gov (United States)

    Kokkinopoulou, Maria; Güler, M Alptekin; Lieb, Bernhard; Barbeck, Mike; Ghanaati, Shahram; Markl, Jürgen

    2014-01-01

    Rhogocytes are pore cells scattered among the connective tissue of different body parts of gastropods and other molluscs, with great variation in their number, shape and size. They are enveloped by a lamina of extracellular matrix. Their most characteristic feature is the "slit apparatus", local invaginations of the plasma membrane bridged by cytoplasmic bars, forming slits of ca. 20 nm width. A slit diaphragm creates a molecular sieve with permeation holes of 20×20 nm. In blue-blooded gastropods, rhogocytes synthesize and secrete the respiratory protein hemocyanin, and it has been proposed-though not proven-that in the rare red-blooded snail species they might synthesize and secrete the hemoglobin. However, the cellular secretion pathway for respiratory proteins, and the functional role(s) of the enigmatic rhogocyte slit apparatus are still unclear. Additional functions for rhogocytes have been proposed, notably a role in protein uptake and degradation, and in heavy metal detoxification. Here we provide new structural and functional information on the rhogocytes of the red-blooded freshwater snail Biomphalaria glabrata. By in situ hybridization of mantle tissues, we prove that rhogocytes indeed synthesize hemoglobin. By electron tomography, the first three dimensional (3D) reconstructions of the slit apparatus are provided, showing detail of highly dense material in the cytoplasmic bars close to the slits. By immunogold labelling, we collected evidence that a major component of this material is actin. By genome databank mining, the complete sequence of a B. glabrata nephrin was obtained, and localized to the rhogocytes by immunofluorescence microscopy. The presence of both proteins fit the ultrastructure-based hypothesis that rhogocytes are related to mammalian podocytes and insect nephrocytes. Reactions of the rhogocytes to deprivation of food and cadmium toxification are also documented, and a possible secretion pathway of newly synthesized respiratory proteins

  8. Evaluation of Structural Cellular Glass

    Science.gov (United States)

    Adams, M. A.; Zwissler, J. G.

    1984-01-01

    Preliminary design information presented. First report discusses state of structural-cellular-glass programs as of June 1979. Second report gives further details of program to develop improved cellular glasses and to characterize properties of glasses and commercially available materials.

  9. Molecular and cellular biology of small-bowel mucosa.

    Science.gov (United States)

    Kitchen, Paul A.; Walters, Julian R.F.

    2001-03-01

    Study of the molecular and cellular biology of the small-intestinal mucosa is providing insights into the remarkable properties of this unique tissue. With its structured pattern of cell proliferation, differentiation, and apoptosis, and its ability to adapt following exposure to luminal nutrients or injury from surgery or pathogens, it functions in a regulated but responsive manner. We review recent publications on factors affecting development, gene expression, cell turnover, and adaptation.

  10. Endothelial cell division in angiogenic sprouts of differing cellular architecture

    OpenAIRE

    Aydogan, Vahap; Lenard, Anna; Denes, Alexandru Stefan; Sauteur, Loic; Belting, Heinz-Georg; Affolter, Markus

    2015-01-01

    ABSTRACT The vasculature of the zebrafish trunk is composed of tubes with different cellular architectures. Unicellular tubes form their lumen through membrane invagination and transcellular cell hollowing, whereas multicellular vessels become lumenized through a chord hollowing process. Endothelial cell proliferation is essential for the subsequent growth and maturation of the blood vessels. However, how cell division, lumen formation and cell rearrangement are coordinated during angiogenic ...

  11. Empirical multiscale networks of cellular regulation.

    Directory of Open Access Journals (Sweden)

    Benjamin de Bivort

    2007-10-01

    Full Text Available Grouping genes by similarity of expression across multiple cellular conditions enables the identification of cellular modules. The known functions of genes enable the characterization of the aggregate biological functions of these modules. In this paper, we use a high-throughput approach to identify the effective mutual regulatory interactions between modules composed of mouse genes from the Alliance for Cell Signaling (AfCS murine B-lymphocyte database which tracks the response of approximately 15,000 genes following chemokine perturbation. This analysis reveals principles of cellular organization that we discuss along four conceptual axes. (1 Regulatory implications: the derived collection of influences between any two modules quantifies intuitive as well as unexpected regulatory interactions. (2 Behavior across scales: trends across global networks of varying resolution (composed of various numbers of modules reveal principles of assembly of high-level behaviors from smaller components. (3 Temporal behavior: tracking the mutual module influences over different time intervals provides features of regulation dynamics such as duration, persistence, and periodicity. (4 Gene Ontology correspondence: the association of modules to known biological roles of individual genes describes the organization of functions within coexpressed modules of various sizes. We present key specific results in each of these four areas, as well as derive general principles of cellular organization. At the coarsest scale, the entire transcriptional network contains five divisions: two divisions devoted to ATP production/biosynthesis and DNA replication that activate all other divisions, an "extracellular interaction" division that represses all other divisions, and two divisions (proliferation/differentiation and membrane infrastructure that activate and repress other divisions in specific ways consistent with cell cycle control.

  12. Empirical multiscale networks of cellular regulation.

    Science.gov (United States)

    de Bivort, Benjamin; Huang, Sui; Bar-Yam, Yaneer

    2007-10-01

    Grouping genes by similarity of expression across multiple cellular conditions enables the identification of cellular modules. The known functions of genes enable the characterization of the aggregate biological functions of these modules. In this paper, we use a high-throughput approach to identify the effective mutual regulatory interactions between modules composed of mouse genes from the Alliance for Cell Signaling (AfCS) murine B-lymphocyte database which tracks the response of approximately 15,000 genes following chemokine perturbation. This analysis reveals principles of cellular organization that we discuss along four conceptual axes. (1) Regulatory implications: the derived collection of influences between any two modules quantifies intuitive as well as unexpected regulatory interactions. (2) Behavior across scales: trends across global networks of varying resolution (composed of various numbers of modules) reveal principles of assembly of high-level behaviors from smaller components. (3) Temporal behavior: tracking the mutual module influences over different time intervals provides features of regulation dynamics such as duration, persistence, and periodicity. (4) Gene Ontology correspondence: the association of modules to known biological roles of individual genes describes the organization of functions within coexpressed modules of various sizes. We present key specific results in each of these four areas, as well as derive general principles of cellular organization. At the coarsest scale, the entire transcriptional network contains five divisions: two divisions devoted to ATP production/biosynthesis and DNA replication that activate all other divisions, an "extracellular interaction" division that represses all other divisions, and two divisions (proliferation/differentiation and membrane infrastructure) that activate and repress other divisions in specific ways consistent with cell cycle control.

  13. Inhibition of human copper trafficking by a small molecule significantly attenuates cancer cell proliferation

    Science.gov (United States)

    Wang, Jing; Luo, Cheng; Shan, Changliang; You, Qiancheng; Lu, Junyan; Elf, Shannon; Zhou, Yu; Wen, Yi; Vinkenborg, Jan L.; Fan, Jun; Kang, Heebum; Lin, Ruiting; Han, Dali; Xie, Yuxin; Karpus, Jason; Chen, Shijie; Ouyang, Shisheng; Luan, Chihao; Zhang, Naixia; Ding, Hong; Merkx, Maarten; Liu, Hong; Chen, Jing; Jiang, Hualiang; He, Chuan

    2015-12-01

    Copper is a transition metal that plays critical roles in many life processes. Controlling the cellular concentration and trafficking of copper offers a route to disrupt these processes. Here we report small molecules that inhibit the human copper-trafficking proteins Atox1 and CCS, and so provide a selective approach to disrupt cellular copper transport. The knockdown of Atox1 and CCS or their inhibition leads to a significantly reduced proliferation of cancer cells, but not of normal cells, as well as to attenuated tumour growth in mouse models. We show that blocking copper trafficking induces cellular oxidative stress and reduces levels of cellular ATP. The reduced level of ATP results in activation of the AMP-activated protein kinase that leads to reduced lipogenesis. Both effects contribute to the inhibition of cancer cell proliferation. Our results establish copper chaperones as new targets for future developments in anticancer therapies.

  14. Effects of fullerenol C60(OH)24 nanoparticles on a single-dose doxorubicin-induced cardiotoxicity in pigs: an ultrastructural study.

    Science.gov (United States)

    Borović, Milica Labudović; Ičević, Ivana; Kanački, Zdenko; Žikić, Dragan; Seke, Mariana; Injac, Rade; Djordjević, Aleksandar

    2014-04-01

    Cardioprotective effects of fullerenol C60(OH)24 nanoparticles (FNP) were investigated in pigs after a single treatment with doxorubicin (DOX). Semithin and ultrathin sections of myocardial tissue routinely prepared for transmission electron microscopy were analyzed. Extensive intracellular damage was confirmed in cardiomyocytes of DOX-treated animals. By means of ultrastructural analysis, a certain degree of parenchymal degeneration was confirmed even in animals treated with FNP alone, including both the oral and the intraperitoneal application of the substance. The cardioprotective effects of FNP in animals previously treated with DOX were recognized to a certain extent, but were not fully confirmed at the ultrastructural level. Nevertheless, the myocardial morphology of DOX-treated animals improved after the admission of FNP. Irregular orientation of myofibrils, myofibrillar disruption, intracellular edema, and vacuolization were reduced, but not completely eliminated. Reduction of these cellular alterations was achieved if FNP was applied orally 6 h prior to DOX treatment in a dose of 18 mg/kg. However, numerous defects, including the inner mitochondrial membrane and the plasma membrane disruption of certain cells persisted. In FNP/DOX-treated animals, the presence of multinuclear cells with mitosis-like figures resembling metaphase or anaphase were observed, indicating that DOX and FNP could have a complex influence on the cell cycle of cardiomyocytes. Based on this experiment, further careful increase in dosage may be advised to enhance FNP-induced cardioprotection. These investigations should, however, always be combined with ultrastructural analysis. The FNP/DOX interaction is an excellent model for the investigation of cardiomyocyte cell death and cell cycle mechanisms.

  15. Germination and ultrastructural studies of seeds produced by a fast-growing, drought-resistant tree: implications for its domestication and seed storage.

    Science.gov (United States)

    Fotouo-M, Helene; du Toit, Elsa S; Robbertse, Petrus J

    2015-02-27

    Seed ageing during storage is one of the main causes of reduction in seed quality and this results in loss of vigour and failure to thrive. Finding appropriate storage conditions to ameliorate deterioration due to ageing is, therefore, essential. Ultrastructural changes in cellular organelles during storage and seed germination rates are valuable indices of damage that occurs during seed ageing. There is increasing interest in Moringa oleifera Lam. because of its multiple uses as an agroforestry crop. Seeds of this species lose their viability within 6-12 months of harvest but no scientific information is available on the longevity of seed stored in the fruit (capsules). In most undeveloped countries, seeds are still stored inside the fruit by traditional methods in special handmade structures. In this experiment we tried to simulate these traditional storage conditions. Capsules of Moringa were stored at ambient room temperature for 12, 24 and 36 months. The ultrastructure, solute leakage and viability of seed were investigated. The ultrastructure of 1-year-old seed showed no sign of deterioration. It was evident, however, that some cells of the 3-year-old seed had deteriorated. The remnants of the outer and inner two integuments that remain tightly attached to the cotyledons probably play a role in seed dormancy. No significant difference was found between germination percentage of fresh and 1-year-old seed. The germination percentage decreased significantly from 2 years of storage onward. The decrease in seed viability during storage was associated with a loss in membrane integrity which was evidenced by an increase in electrolyte leakage. Our findings indicate that the longevity of M. oleifera seeds can be maintained if they are stored within their capsules. Published by Oxford University Press on behalf of the Annals of Botany Company.

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

    Directory of Open Access Journals (Sweden)

    Ahmed Mahmoud Halawa

    2016-06-01

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

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

    Directory of Open Access Journals (Sweden)

    Evelyn Rabelo Andrade

    2011-01-01

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

  18. 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

  19. Mitochondrial disruption and limited apoptosis of erythroblasts are associated with high risk myelodysplasia. An ultrastructural analysis

    NARCIS (Netherlands)

    van de Loosdrecht, AA; Brada, SJL; Blom, NR; Smit, JW; van den Berg, E; de Wolf, JTM; Vellenga, E

    Aims: To investigate the ultrastructural characteristics of erythroblasts in myelodysplasia (MDS) which might be of additional importance in understanding its pathogenesis. Methods and results: 22 patients were classified according to FAB (French-American-British classification), IPSS (international

  20. Cellular communication through light.

    Directory of Open Access Journals (Sweden)

    Daniel Fels

    Full Text Available Information transfer is a fundamental of life. A few studies have reported that cells use photons (from an endogenous source as information carriers. This study finds that cells can have an influence on other cells even when separated with a glass barrier, thereby disabling molecule diffusion through the cell-containing medium. As there is still very little known about the potential of photons for intercellular communication this study is designed to test for non-molecule-based triggering of two fundamental properties of life: cell division and energy uptake. The study was performed with a cellular organism, the ciliate Paramecium caudatum. Mutual exposure of cell populations occurred under conditions of darkness and separation with cuvettes (vials allowing photon but not molecule transfer. The cell populations were separated either with glass allowing photon transmission from 340 nm to longer waves, or quartz being transmittable from 150 nm, i.e. from UV-light to longer waves. Even through glass, the cells affected cell division and energy uptake in neighboring cell populations. Depending on the cuvette material and the number of cells involved, these effects were positive or negative. Also, while paired populations with lower growth rates grew uncorrelated, growth of the better growing populations was correlated. As there were significant differences when separating the populations with glass or quartz, it is suggested that the cell populations use two (or more frequencies for cellular information transfer, which influences at least energy uptake, cell division rate and growth correlation. Altogether the study strongly supports a cellular communication system, which is different from a molecule-receptor-based system and hints that photon-triggering is a fine tuning principle in cell chemistry.

  1. Cellular communication through light.

    Science.gov (United States)

    Fels, Daniel

    2009-01-01

    Information transfer is a fundamental of life. A few studies have reported that cells use photons (from an endogenous source) as information carriers. This study finds that cells can have an influence on other cells even when separated with a glass barrier, thereby disabling molecule diffusion through the cell-containing medium. As there is still very little known about the potential of photons for intercellular communication this study is designed to test for non-molecule-based triggering of two fundamental properties of life: cell division and energy uptake. The study was performed with a cellular organism, the ciliate Paramecium caudatum. Mutual exposure of cell populations occurred under conditions of darkness and separation with cuvettes (vials) allowing photon but not molecule transfer. The cell populations were separated either with glass allowing photon transmission from 340 nm to longer waves, or quartz being transmittable from 150 nm, i.e. from UV-light to longer waves. Even through glass, the cells affected cell division and energy uptake in neighboring cell populations. Depending on the cuvette material and the number of cells involved, these effects were positive or negative. Also, while paired populations with lower growth rates grew uncorrelated, growth of the better growing populations was correlated. As there were significant differences when separating the populations with glass or quartz, it is suggested that the cell populations use two (or more) frequencies for cellular information transfer, which influences at least energy uptake, cell division rate and growth correlation. Altogether the study strongly supports a cellular communication system, which is different from a molecule-receptor-based system and hints that photon-triggering is a fine tuning principle in cell chemistry.

  2. Review of cellular mechanotransduction

    Science.gov (United States)

    Wang, Ning

    2017-06-01

    Living cells and tissues experience physical forces and chemical stimuli in the human body. The process of converting mechanical forces into biochemical activities and gene expression is mechanochemical transduction or mechanotransduction. Significant advances have been made in understanding mechanotransduction at the cellular and molecular levels over the last two decades. However, major challenges remain in elucidating how a living cell integrates signals from mechanotransduction with chemical signals to regulate gene expression and to generate coherent biological responses in living tissues in physiological conditions and diseases.

  3. Engineering Cellular Metabolism

    DEFF Research Database (Denmark)

    Nielsen, Jens; Keasling, Jay

    2016-01-01

    Metabolic engineering is the science of rewiring the metabolism of cells to enhance production of native metabolites or to endow cells with the ability to produce new products. The potential applications of such efforts are wide ranging, including the generation of fuels, chemicals, foods, feeds...... of metabolic engineering and will discuss how new technologies can enable metabolic engineering to be scaled up to the industrial level, either by cutting off the lines of control for endogenous metabolism or by infiltrating the system with disruptive, heterologous pathways that overcome cellular regulation....

  4. Cellular mechanics and motility

    Science.gov (United States)

    Hénon, Sylvie; Sykes, Cécile

    2015-10-01

    The term motility defines the movement of a living organism. One widely known example is the motility of sperm cells, or the one of flagellar bacteria. The propulsive element of such organisms is a cilium(or flagellum) that beats. Although cells in our tissues do not have a flagellum in general, they are still able to move, as we will discover in this chapter. In fact, in both cases of movement, with or without a flagellum, cell motility is due to a dynamic re-arrangement of polymers inside the cell. Let us first have a closer look at the propulsion mechanism in the case of a flagellum or a cilium, which is the best known, but also the simplest, and which will help us to define the hydrodynamic general conditions of cell movement. A flagellum is sustained by cellular polymers arranged in semi-flexible bundles and flagellar beating generates cell displacement. These polymers or filaments are part of the cellular skeleton, or "cytoskeleton", which is, in this case, external to the cellular main body of the organism. In fact, bacteria move in a hydrodynamic regime in which viscosity dominates over inertia. The system is thus in a hydrodynamic regime of low Reynolds number (Box 5.1), which is nearly exclusively the case in all cell movements. Bacteria and their propulsion mode by flagella beating are our unicellular ancestors 3.5 billion years ago. Since then, we have evolved to form pluricellular organisms. However, to keep the ability of displacement, to heal our wounds for example, our cells lost their flagellum, since it was not optimal in a dense cell environment: cells are too close to each other to leave enough space for the flagella to accomplish propulsion. The cytoskeleton thus developed inside the cell body to ensure cell shape changes and movement, and also mechanical strength within a tissue. The cytoskeleton of our cells, like the polymers or filaments that sustain the flagellum, is also composed of semi-flexible filaments arranged in bundles, and also in

  5. The thorny path linking cellular senescence to organismalaging

    Energy Technology Data Exchange (ETDEWEB)

    Patil, Christopher K.; Mian, Saira; Campisi, Judith

    2005-08-09

    Half a century is fast approaching since Hayflick and colleagues formally described the limited ability of normal human cells to proliferate in culture (Hayflick and Moorhead, 1961). This finding--that normal somatic cells, in contrast to cancer cells, cannot divide indefinitely--challenged the prevailing idea that cells from mortal multicellular organisms were intrinsically ''immortal'' (Carrell, 1912). It also spawned two hypotheses, essential elements of which persist today. The first held that the restricted proliferation of normal cells, now termed cellular senescence, suppresses cancer (Hayflick, 1965; Sager, 1991; Campisi, 2001). The second hypothesis, as explained in the article by Lorenzini et al., suggested that the limited proliferation of cells in culture recapitulated aspects of organismal aging (Hayflick, 1965; Martin, 1993). How well have these hypotheses weathered the ensuing decades? Before answering this question, we first consider current insights into the causes and consequences of cellular senescence. Like Lorenzini et al., we limit our discussion to mammals. We also focus on fibroblasts, the cell type studied by Lorenzini et al., but consider other types as well. We suggest that replicative capacity in culture is not a straightforward assessment, and that it correlates poorly with both longevity and body mass. We speculate this is due to the malleable and variable nature of replicative capacity, which renders it an indirect metric of qualitative and quantitative differences among cells to undergo senescence, a response that directly alters cellular phenotype and might indirectly alter tissue structure and function.

  6. Spatial distribution and cellular composition of adult brain proliferative zones in the teleost, Gymnotus omarorum

    Directory of Open Access Journals (Sweden)

    Valentina eOlivera-Pasilio

    2014-09-01

    Full Text Available Proliferation of stem/progenitor cells during development provides for the generation of mature cell types in the CNS. While adult brain proliferation is highly restricted in the mammals, it is widespread in teleosts. The extent of adult neural proliferation in the weakly electric fish, Gymnotus omarorum has not yet been described. To address this, we used double thymidine analog pulse-chase labeling of proliferating cells to identify brain proliferation zones, characterize their cellular composition, and analyze the fate of newborn cells in adult G. omarorum. Short thymidine analog chase periods revealed the ubiquitous distribution of adult brain proliferation, similar to other teleosts, particularly Apteronotus leptorhynchus. Proliferating cells were abundant at the ventricular-subventricular lining of the ventricular-cisternal system, adjacent to the telencephalic subpallium, the diencephalic preoptic region and hypothalamus, and the mesencephalic tectum opticum and torus semicircularis. Extraventricular proliferation zones, located distant from the ventricular-cisternal system surface, were found in all divisions of the rombencephalic cerebellum. We also report a new adult proliferation zone at the caudal-lateral border of the electrosensory lateral line lobe. All proliferation zones showed a heterogeneous cellular composition. The use of short (24hs and long (30d chase periods revealed abundant fast cycling cells (potentially intermediate amplifiers, sparse slow cycling (potentially stem cells, cells that appear to have entered a quiescent state, and cells that might correspond to migrating newborn neural cells. Their abundance and migration distance differed among proliferation zones: greater numbers and longer range and/or pace of migrating cells were associated with subpallial and cerebellar proliferation zones.

  7. [Ultrastructure of endometrium during low-dose gestagenic anticonception (author's transl)].

    Science.gov (United States)

    Houdek, J; Pelák, Z; Vacek, Z

    1977-02-01

    31 women (average age, 26 years) were administered a modified low dosage gestagen contraceptive, containing .3 of norethisterone for an average period of 10.6 months. Changes in the ultrastructure of the endometrium were studied throughout this period. Changes in both parts of the ultrastructure, the fibrose and epithelial parts, were revealed in comparison to material taken before use of the preparation. Changes in the stromata cells were particularly of a gestagenic character. Epithelial cells also demonstrated a particularly gestagenic stimulation.

  8. Endothelin-1 regulates astrocyte proliferation and reactive gliosis via a JNK/c-Jun signaling pathway

    OpenAIRE

    Gadea, Ana; Schinelli, Sergio; Gallo, Vittorio

    2008-01-01

    Reactive gliosis is characterized by enhanced glial fibrillary acidic protein (GFAP) expression, cellular hypertrophy and astrocyte proliferation. The cellular and molecular mechanisms underlying this process are still largely undefined. We investigated the role of Endothelin-1 (ET-1) in reactive gliosis in corpus callosum after lysolecithin (LPC)-induced focal demyelination, and in cultured astrocytes. We show that ET-1 levels are upregulated in demyelinated lesions within five days after LP...

  9. Gain in cellular organization of inflammatory breast cancer: A 3D in vitro model that mimics the in vivo metastasis

    International Nuclear Information System (INIS)

    Morales, Jorge; Alpaugh, Mary L

    2009-01-01

    The initial step of metastasis in carcinomas, often referred to as the epithelial-mesenchymal transition (EMT), occurs via the loss of adherens junctions (e.g. cadherins) by the tumor embolus. This leads to a subsequent loss of cell polarity and cellular differentiation and organization, enabling cells of the embolus to become motile and invasive. However highly malignant inflammatory breast cancer (IBC) over-expresses E-cadherin. The human xenograft model of IBC (MARY-X), like IBC, displays the signature phenotype of an exaggerated degree of lymphovascular invasion (LVI) in situ by tumor emboli. An intact E-cadherin/α, β-catenin axis mediates the tight, compact clump of cells found both in vitro and in vivo as spheroids and tumor emboli, respectively. Using electron microscopy and focused ion beam milling to acquire in situ sections, we performed ultrastructural analysis of both an IBC and non-IBC, E-cadherin positive cell line to determine if retention of this adhesion molecule contributed to cellular organization. Here we report through ultrastructural analysis that IBC exhibits a high degree of cellular organization with polar elements such as apical/lateral positioning of E-cadherin, apical surface microvilli, and tortuous lumen-like (canalis) structures. In contrast, agarose-induced spheroids of MCF-7, a weakly invasive E-cadherin positive breast carcinoma cell line, do not exhibit ultrastructural polar features. This study has determined that the highly metastatic IBC with an exaggerated malignant phenotype challenges conventional wisdom in that instead of displaying a loss of cellular organization, IBC acquires a highly structured architecture. These findings suggest that the metastatic efficiency might be linked to the formation and maintenance of these architectural features. The comparative architectural features of both the spheroid and embolus of MARY-X provide an in vitro model with tractable in vivo applications

  10. Future non-proliferation challenges

    International Nuclear Information System (INIS)

    Yelchenko, Volodymyr

    2008-01-01

    Having chaired the Second Session of the Preparatory Committee Mr. Volodymyr Yelchenko noted that the NPT States parties reaffirmed the important role of the Treaty as the cornerstone of the global non-proliferation regime. They stressed that non-compliance with the Treaty provisions by States parties undermined non-proliferation and placed emphasis on the mutually reinforcing nature of disarmament and non-proliferation, and due respect for the right of States parties to the peaceful use of nuclear energy in conformity with the treaty. They reaffirmed the importance of promoting the peaceful uses of nuclear energy and international nuclear cooperation for peaceful purposes in ways consistent with the non-proliferation goal of the Treaty. The universality aspect was brought to the front with the lack of progress in this area. States parties called upon India, Israel and Pakistan to accede to the Treaty as non-nuclear-weapons states, promptly and without conditions and to bring into force comprehensive safeguards agreements, together with Additional Protocols, for ensuring non-proliferation. There is concern that non-States actors could gain access to weapons of mass destruction. One of the underlying themes at the Second Prepcom was the total elimination of nuclear weapons as the only absolute guarantee against their proliferation. Negative consequences to nuclear non-proliferation were also mentioned in the context of the abrogation of the Anti-Ballistic Missile Treaty and the development of missile defense systems, with the risk of a new arms race on Earth and in outer space. The importance of the immediate commencement of negotiations in the Conference of Disarmament on a treaty concerning fissile material for nuclear weapons or other nuclear explosive devices and the urgent conclusion of such a treaty as a beneficial step towards non-proliferation was stressed. The NPT states parties reaffirmed the role of the IAEA as the sole competent authority responsible for

  11. Correlative Microscopy of Lamellar Hole-Associated Epiretinal Proliferation

    Directory of Open Access Journals (Sweden)

    Denise Compera

    2015-01-01

    Full Text Available Purpose. To describe morphology of lamellar hole-associated epiretinal proliferation (LHEP removed from eyes with lamellar macular holes (LMH. Methods. Based on optical coherence tomography data, 10 specimens of LHEP were removed from 10 eyes with LMH during standard vitrectomy. Specimens were prepared for correlative light and electron microscopy (CLEM using an immunonanogold particle of 1.4 nm diameter that was combined with a fluorescein moiety, both having been attached to a single antibody fragment. As primary antibodies, we used antiglial fibrillary acidic protein (GFAP, anti-CD45, anti-CD64, anti-α-smooth muscle actin (α-SMA, and anticollagen type I and type II. Results. In LHEP, GFAP-positive cells possess ultrastructural characteristics of fibroblasts and hyalocytes. They represent the major cell types and were densely packed in cell agglomerations on vitreous collagen strands. Epiretinal cells of LHEP rarely demonstrated contractive properties as α-SMA-positive myofibroblasts were an infrequent finding. Conclusion. CLEM indicates that epiretinal cells in LHEP might originate from the vitreous and that remodelling processes of vitreous collagen may play an important role in pathogenesis of eyes with LMH.

  12. Cellular architecture mediates DivIVA ultrastructure and regulates min activity in Bacillus subtilis | Center for Cancer Research

    Science.gov (United States)

    The Min system in rod-shaped bacteria restricts improper assembly of the division septum. In Escherichia coli, the Min system localizes to the cell poles, but in Bacillus subtilis, it is recruited to nascent cell division sites at mid-cell to prevent aberrant septation events immediately adjacent to a constricting septum. How does the cell spatially and temporally restrict the inhibitory activity of the Min system so that it does not interfere with normal cell division?

  13. Regulation of proliferation of embryonic heart mesenchyme: Role of transforming growth factor-beta 1 and the interstitial matrix

    Energy Technology Data Exchange (ETDEWEB)

    Choy, M.; Armstrong, M.T.; Armstrong, P.B. (Univ. of California Davis Medical Center, Sacramento (USA))

    1990-10-01

    Proliferation of atrioventricular cushion mesenchyme of the embryonic avian heart maintained in three-dimensional aggregate culture is stimulated by interaction with the interstitial matrix. Chicken serum or transforming growth factor-beta 1, which stimulates proliferation, induces matrix deposition in regions of the aggregate showing high labeling indices with tritiated thymidine. Dispersed heart mesenchyme interstitial matrix introduced into serum-free culture is incorporated into the aggregate and stimulates cellular proliferation similar to serum or transforming growth factor-beta 1. Proliferation is reversibly inhibited by the peptide Gly-Arg-Gly-Asp-Ser-Pro. It is suggested that transforming growth factor-beta 1 stimulates the production of interstitial matrix and that a sufficient stimulus for proliferation in this system is the presence of the matrix, which acts as the adhesive support for cellular anchorage.

  14. Regulation of proliferation of embryonic heart mesenchyme: Role of transforming growth factor-beta 1 and the interstitial matrix

    International Nuclear Information System (INIS)

    Choy, M.; Armstrong, M.T.; Armstrong, P.B.

    1990-01-01

    Proliferation of atrioventricular cushion mesenchyme of the embryonic avian heart maintained in three-dimensional aggregate culture is stimulated by interaction with the interstitial matrix. Chicken serum or transforming growth factor-beta 1, which stimulates proliferation, induces matrix deposition in regions of the aggregate showing high labeling indices with tritiated thymidine. Dispersed heart mesenchyme interstitial matrix introduced into serum-free culture is incorporated into the aggregate and stimulates cellular proliferation similar to serum or transforming growth factor-beta 1. Proliferation is reversibly inhibited by the peptide Gly-Arg-Gly-Asp-Ser-Pro. It is suggested that transforming growth factor-beta 1 stimulates the production of interstitial matrix and that a sufficient stimulus for proliferation in this system is the presence of the matrix, which acts as the adhesive support for cellular anchorage

  15. Spatiotemporal distribution of proliferation, proapoptotic and antiapoptotic factors in the early human limb development.

    Science.gov (United States)

    Bečić, Tina; Bilan, Kanito; Mardešić, Snježana; Vukojević, Katarina; Saraga-Babić, Mirna

    2016-06-01

    Involvement of proliferation and apoptosis in the human limb development was analyzed electronmicroscopically and immunohistochemically in histological sections of 8 human embryos, 4(th) -10(th) week old, using apoptotic (caspase-3, AIF, BAX), anti-apoptotic (Bcl-2) and proliferation (Ki-67) markers, and TUNEL method. The data were analyzed by Mann-Whitney test, Kruskal-Wallis and Dunn's post hoc test. Initially, developing human limbs consisted of mesenchymal core and surface ectoderm with apical ectodermal ridge (AER). During progression of development, strong proliferation activity gradually decreased in the mesenchyme (from 78% to 68%) and in the epithelium (from 62% to 42%), while in the differentiating finger cartilages proliferation was constantly low (26-7%). Apoptotic caspase-3 and AIF-positive cells characterized mesenchyme and AER at earliest stages, while during digit separation they appeared in interdigital mesenchyme as well. Strong Bcl-2 expression was observed in AER, subridge mesenchyme and phalanges, while BAX expression charaterized limb areas undergoing apoptosis. Ultrastructurally, proliferating cells showed mitotic figures, while apoptotic cells were characterized by nuclear fragmentation. Macrophages were observed around the apoptotic cells. We suggest that intense proliferation enables growth and elongation of human limb primordia, and differential growth of digits. Both caspase-3 and AIF-dependant pathways of cell death control the extent of AER and numer of cells in the subridge mesenchyme at earliest developmental stages, as well as process of digit separation at later stages of limb development. Spatio-temporal co-expresson of Bcl-2 and BAX indicates their role in suppression of apoptosis and selective stimulation of growth during human limb morphogenesis. Copyright © 2016 Elsevier GmbH. All rights reserved.

  16. A morphological study of the changes in the ultrastructure of a bacterial biofilm disrupted by an ac corona discharge in air

    Energy Technology Data Exchange (ETDEWEB)

    Stepanova, Olga, E-mail: o.m.stepanova@spbu.ru; Astafiev, Alexander; Kudryavtsev, Anatoly [Physical Faculty, Saint Petersburg State University, St. Petersburg (Russian Federation); Rybalchenko, Oksana; Orlova, Olga; Kapustina, Valentina [Faculty of Medicine, Saint Petersburg State University, St. Petersburg (Russian Federation)

    2016-08-14

    The morphology of bacterial cells and biofilms subjected to a low frequency (∼10{sup 5} Hz) ac (∼10{sup −1} A) corona discharge was investigated using electron microscopy. A low-frequency ac corona discharge in air is shown to have a bactericidal and bacteriostatic effect on Escherichia coli M17 culture at both the cellular and population levels. Corona exposure inhibits the formation of a microbial community and results in the destruction of formed biofilms. This paper presents data on changes in the ultrastructure of cells and biofilms after corona treatment. Our results suggest that the E. coli M17 cells inside biofilms are affected with results similar to sub-lethal and lethal thermal exposure. Some of the biological aspects of colony and biofilm cells death are evaluated. Morphological changes in the ultrastructure of the biofilms under corona treatment are described. Our results indicate that the heating effect is the main factor responsible for the corona-induced inactivation of bacteria.

  17. 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.

  18. Cellular mechanisms in drug - radiation interaction

    International Nuclear Information System (INIS)

    Trott, K.R.

    1979-01-01

    Some cytotoxic drugs, especially those belonging to the group of antibiotics and antimetabolites, sensitize the cells having survived drug treatment to the subsequent irradiation by either increasing the slope of the radiation dose response curves or by decreasing extrapolation number. Bleomycin was found to interact with radiation in L-cells and FM3A cells, but not in HeLa-cells. The data with EMT-6 cells suggest that the interaction depends on drug dose: no interaction occurred after the exposure to bleomycin which killed only 20 - 40% of the cells; yet the exposure to bleomycin which killed 90% of the cells in addition sensitized the surviving cells by the DMF of 1.3. The sensitization found 24 hr after the exposure of HeLa cells to methotrexate was due to cell synchronization. Other cytostatic drugs were found to synchronize proliferating cells even better. Therefore, the fluctuation of radiosensitivity has been commonly observed after the termination of exposure to these drugs. Preirradiation may lead to the change in drug dose response curves. The recruitment of resting cells into cycle occurs hours or days later, in some irradiated normal and malignant tissues. Since many cytostatic drugs are far more active in proliferating cells than in resting cells, the recruitment after irradiation may lead to the sudden increase in drug sensitivity, days after the irradiation. No single, simple theory seems to exist to classify and predict the cellular response to combined modality treatment. (Yamashita, S.)

  19. CELLULAR RESPONSES TO EGG-OIL (CHARISMON©

    Directory of Open Access Journals (Sweden)

    Jürgen Bereiter-Hahn

    2014-01-01

    Full Text Available Egg-oil (Charismon© is known for its beneficial action in wound healing and other skin irritancies and its antibacterial activity. The physiological basis for these actions has been investigated using cells in culture: HaCaT-cells (immortalized human keratinocytes, human endothelial cells in culture (HUVEC, peripheral blood mononuclear lymphocytes (PBML and a full thickness human skin model (FTSM. Emphasis was on the influence of egg-oil on cell migration and IL-8 production in HaCaT cells, respiration, mitochondrial membrane potential, reactive oxygen (ROS production and proliferation in HUVEC and HaCaT cells, cytokine and interleukin production in PBML and UV-light induced damage of FTSM. IL-8 production by HaCaT cells is stimulated by egg-oil whilst in phythemagglutinin-activated PBMLs production of the interleukins IL-2, IL-6, IL-10 and IFN-γ and TFN-α is reduced. ROS-production after H2O2 stimulation first is enhanced but later on reduced. Respiration becomes activated due to partial uncoupling of the mitochondrial respiratory chain and proliferation of HaCaT and HUVEC is reduced. Recovery of human epidermis cells in FTSM after UV-irradiation is strongly supported by egg-oil. These results support the view that egg-oil acts through reduction of inflammatory processes and ROS production. Both these processes are equally important in cellular aging as in healing of chronic wounds.

  20. Cellular image classification

    CERN Document Server

    Xu, Xiang; Lin, Feng

    2017-01-01

    This book introduces new techniques for cellular image feature extraction, pattern recognition and classification. The authors use the antinuclear antibodies (ANAs) in patient serum as the subjects and the Indirect Immunofluorescence (IIF) technique as the imaging protocol to illustrate the applications of the described methods. Throughout the book, the authors provide evaluations for the proposed methods on two publicly available human epithelial (HEp-2) cell datasets: ICPR2012 dataset from the ICPR'12 HEp-2 cell classification contest and ICIP2013 training dataset from the ICIP'13 Competition on cells classification by fluorescent image analysis. First, the reading of imaging results is significantly influenced by one’s qualification and reading systems, causing high intra- and inter-laboratory variance. The authors present a low-order LP21 fiber mode for optical single cell manipulation and imaging staining patterns of HEp-2 cells. A focused four-lobed mode distribution is stable and effective in optical...

  1. Cellular-scale hydrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Abkarian, Manouk [Laboratoire des Colloides, Verres et Nanomateriaux, Universite de Montpellier, Montpellier Cedex 5 (France); Faivre, Magalie [CEA-LETI, Division of Technology for Biology and Health, 17, Avenue des Martyrs, 38054 Grenoble (France); Horton, Renita; Stone, Howard A [School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138 (United States); Smistrup, Kristian [MIC, Department of Micro and Nanotechnology, Technical University of Denmark, DK-2800, Kongens Lyngby (Denmark); Best-Popescu, Catherine A [Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, IL 61801 (United States)

    2008-09-01

    Microfluidic tools are providing many new insights into the chemical, physical and physicochemical responses of cells. Both suspension-level and single-cell measurements have been studied. We review our studies of these kinds of problems for red blood cells with particular focus on the shapes of individual cells in confined geometries, the development and use of a 'differential manometer' for evaluating the mechanical response of individual cells or other objects flowing in confined geometries, and the cross-streamline drift of cells that pass through a constriction. In particular, we show how fluid mechanical effects on suspended cells can be studied systematically in small devices, and how these features can be exploited to develop methods for characterizing physicochemical responses and possibly for the diagnosis of cellular-scale changes to environmental factors.

  2. Cellular based cancer vaccines

    DEFF Research Database (Denmark)

    Hansen, M; Met, Ö; Svane, I M

    2012-01-01

    -associated antigens introduced to dendritic cells (DCs) generated in vitro. This may in part result from suboptimal maturation of DCs leading to insufficient production of IL-12, a key driver of cellular immunity. Therefore, tremendous efforts have been put into the design of maturation cocktails that are able...... of tolerogenic molecules and activation-induced dendritic cell death should be avoided. Thus, compounds such as IFN-γ may initially induce immunity but later on tolerance. Maturation with PGE(2) obviously promotes migration via expression of CCR7 but on the down side PGE(2) limits the production of IL-12...... to transiently affect in vitro migration via autocrine receptor-mediated endocytosis of CCR7. In the current review, we discuss optimal design of DC maturation focused on pre-clinical as well as clinical results from standard and polarized dendritic cell based cancer vaccines....

  3. Nuclear proliferation and safeguards. Summary

    International Nuclear Information System (INIS)

    1982-03-01

    This comprehensive analysis of the technological, economic, and political factors affecting the potential spread of nuclear weapons proved useful in the congressional debate which culminated in the Nuclear Non-Proliferation Act of 1978. The report was subsequently published commercially and has been a frequently cited reference in the literature on proliferation and nuclear power. Despite developments since 1977, the information in the OTA report is still useful to those wishing to obtain an indepth understanding of the issues. Included is an analysis of why a nation might want nuclear weapons development program and the various sources of nuclear material are discussed. The control of proliferation is considered as well as its relation to the nuclear industry

  4. Combinatorial approaches to evaluate nanodiamond uptake and induced cellular fate

    International Nuclear Information System (INIS)

    Eldawud, Reem; Dinu, Cerasela Zoica; Reitzig, Manuela; Opitz, Jörg; Rojansakul, Yon; Jiang, Wenjuan; Nangia, Shikha

    2016-01-01

    Nanodiamonds (NDs) are an emerging class of engineered nanomaterials that hold great promise for the next generation of bionanotechnological products to be used for drug and gene delivery, or for bio-imaging and biosensing. Previous studies have shown that upon their cellular uptake, NDs exhibit high biocompatibility in various in vitro and in vivo set-ups. Herein we hypothesized that the increased NDs biocompatibility is a result of minimum membrane perturbations and their reduced ability to induce disruption or damage during cellular translocation. Using multi-scale combinatorial approaches that simulate ND-membrane interactions, we correlated NDs real-time cellular uptake and kinetics with the ND-induced membrane fluctuations to derive energy requirements for the uptake to occur. Our discrete and real-time analyses showed that the majority of NDs internalization occurs within 2 h of cellular exposure, however, with no effects on cellular viability, proliferation or cellular behavior. Furthermore, our simulation analyses using coarse-grained models identified key changes in the energy profile, membrane deformation and recovery time, all functions of the average ND or ND-based agglomerate size. Understanding the mechanisms responsible for ND-cell membrane interactions could possibly advance their implementation in various biomedical applications. (paper)

  5. Combinatorial approaches to evaluate nanodiamond uptake and induced cellular fate.

    Science.gov (United States)

    Eldawud, Reem; Reitzig, Manuela; Opitz, Jörg; Rojansakul, Yon; Jiang, Wenjuan; Nangia, Shikha; Dinu, Cerasela Zoica

    2016-02-26

    Nanodiamonds (NDs) are an emerging class of engineered nanomaterials that hold great promise for the next generation of bionanotechnological products to be used for drug and gene delivery, or for bio-imaging and biosensing. Previous studies have shown that upon their cellular uptake, NDs exhibit high biocompatibility in various in vitro and in vivo set-ups. Herein we hypothesized that the increased NDs biocompatibility is a result of minimum membrane perturbations and their reduced ability to induce disruption or damage during cellular translocation. Using multi-scale combinatorial approaches that simulate ND-membrane interactions, we correlated NDs real-time cellular uptake and kinetics with the ND-induced membrane fluctuations to derive energy requirements for the uptake to occur. Our discrete and real-time analyses showed that the majority of NDs internalization occurs within 2 h of cellular exposure, however, with no effects on cellular viability, proliferation or cellular behavior. Furthermore, our simulation analyses using coarse-grained models identified key changes in the energy profile, membrane deformation and recovery time, all functions of the average ND or ND-based agglomerate size. Understanding the mechanisms responsible for ND-cell membrane interactions could possibly advance their implementation in various biomedical applications.

  6. Straight sinus: ultrastructural analysis aimed at surgical tumor resection.

    Science.gov (United States)

    Amato, Marcelo Campos Moraes; Tirapelli, Luis Fernando; Carlotti, Carlos Gilberto; Colli, Benedicto Oscar

    2016-08-01

    OBJECTIVE Accurate knowledge of the anatomy of the straight sinus (SS) is relevant for surgical purposes. During one surgical procedure involving the removal of part of the SS wall, the authors observed that the venous blood flow was maintained in the SS, possibly through a vein-like structure within the dural sinus or dural multiple layers. This observation and its divergence from descriptions of the histological features of the SS walls motivated the present study. The authors aimed to investigate whether it is possible to dissect the SS walls while keeping the lumen intact, and to describe the histological and ultrastructural composition of the SS wall. METHODS A total of 22 cadaveric specimens were used. The SS was divided into three portions: anterior, middle, and posterior. The characteristics of the SS walls were analyzed, and the feasibility of dissecting them while keeping the SS lumen intact was assessed. The thickness and the number of collagen fibers and other tissues in the SS walls were compared with the same variables in other venous sinuses. Masson's trichrome and Verhoeff's stains were used to assess collagen and elastic fibers, respectively. The data were analyzed using Zeiss image analysis software (KS400). RESULTS A vein-like structure independent of the SS walls was found in at least one of the portions of the SS in 8 of 22 samples (36.36%). The inferior wall could be delaminated in at least one portion in 21 of 22 samples (95.45%), whereas the lateral walls could seldom be delaminated. The inferior wall of the SS was thicker (p < 0.05) and exhibited less collagen and greater amounts of other tissues-including elastic fibers, connective tissue, blood vessels, and nerve fibers (p < 0.05)-compared with the lateral walls. Transmission electron microscopy revealed the presence of muscle fibers at a level deeper than that of the subendothelial connective tissue in the inferior wall of the SS, extending from its junction with the great cerebral vein

  7. Ultrastructure and mineral composition of urinary calculi from horses.

    Science.gov (United States)

    Neumann, R D; Ruby, A L; Ling, G V; Schiffman, P; Johnson, D L

    1994-10-01

    Urinary calculi from 17 horses with urolithiasis were examined to study their mineral content and ultrastructure. Among the analytic methods used were X-ray diffractometry, scanning electron microscopy, and electron microprobe analysis. The calculi initially were observed by use of a stereoscopic dissecting microscope and generally were found to have nodular surfaces surrounding a banded or granular-to-chalky interior. Observation by scanning electron microscopy revealed an intricate pattern of irregularly concentric, fine bands and spherules. These had a round, finely banded, globular texture formed by precipitation of ultrafine-grained radiating crystals. The original pore spaces (ie, between spherules, between bands and spherules, or between crystal generations) could be observed as primary porosity. Precipitation and dissolution of these urinary calculi were observed to be spontaneous processes, which can occur simultaneously within an individual calculus. Another prominent feature of the ultrastructure was secondary porosity (spontaneous dissolution) which, in its incipient stages, appeared to be site-selective (ie, some bands appeared to be more susceptible to development of pinpoint porosity). Textures indicative of dissolution were observed not only on the calculus surface, but within the calculus interior as well. Areas that had more advanced stages of dissolution, resulting in increased secondary porosity, also were observed. All 17 samples of the study were found to be composed of calcium carbonate in the form of the mineral calcite, although minor quantities of 2 other polymorphs of calcium carbonate, minerals vaterite and aragonite, also were encountered. Vaterite was observed in 5 of the samples, whereas aragonite was found in 1 sample. Strontium and sulfur were observed as trace elements in 3 of the calculi, whereas magnesium was present in all calculi. Magnesium was observed to substitute for calcium within the calcite crystal lattice in larger

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

    Science.gov (United States)

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

    2014-01-01

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

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

    Science.gov (United States)

    Sever, David M; Freeborn, Layla R

    2012-03-01

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

  10. Ultracentrifuge and non-proliferation

    International Nuclear Information System (INIS)

    Voortman, A.J.

    1977-01-01

    The author states that there is no meaningful difference, from the point of view of proliferation between peaceful, civil, scientific application of nuclear fission, and the use of it in nuclear weapons. The proliferation of the nuclear technology for weapons appeared and appears to be closely connected with the spread of peaceful applications of nuclear technology. In connection with this, he discusses the Ultracentrifuge plant at Almelo (Netherlands) and the supply of nuclear technology by West-Germany especially to Brazil. Further the changed American policy and the possibility of an American/Russian deal to prevent the spread of the nuclear enrichment technology is discussed

  11. Lymphocyte Proliferation Response in Patients with Acute and Chronic Brucellosis

    Directory of Open Access Journals (Sweden)

    Khadijeh Khosravi

    2016-05-01

    Full Text Available Abstract Background: Brucella is an intracellular bacterium that causes chronic infection in humans and domestic animals. The underlying mechanisms that cause prolonged illness are complex and not fully understood. Immune responses may have an important role in the chronicity of infection. Here, we evaluated the lymphocyte proliferation responses in patients with chronic and acute brucellosis. Materials and Methods: This descriptive - analytical study was performed on 22 patients with acute brucellosis, 21 patients with chronic brucellosis and 21 healthy people with the similar age, sex and genetic background as control group. Peripheral lymphocytes were isolated using Ficoll and the cellular proliferation was quantified in presence of antigen and phytohemaglutinin-A by MTT method. Results: The brucella antigen-specific stimulation index in patients with chronic brucellosis was significantly lower than the acute brucellosis patients (p=0.001. Also, stimulating the lymphocytes with phytohemaglutinin-A has shown that proliferative response in patients with chronic brucellosis was lower than the other groups (p=0.04. Conclusion: The results indicated that chronic brucellosis inhibits lymphocyte proliferation. This inhibition of lymphocyte proliferation may be due to the induction of anergy.

  12. Cellular contractility requires ubiquitin mediated proteolysis.

    Directory of Open Access Journals (Sweden)

    Yuval Cinnamon

    Full Text Available BACKGROUND: Cellular contractility, essential for cell movement and proliferation, is regulated by microtubules, RhoA and actomyosin. The RhoA dependent kinase ROCK ensures the phosphorylation of the regulatory Myosin II Light Chain (MLC Ser19, thereby activating actomyosin contractions. Microtubules are upstream inhibitors of contractility and their depolymerization or depletion cause cells to contract by activating RhoA. How microtubule dynamics regulates RhoA remains, a major missing link in understanding contractility. PRINCIPAL FINDINGS: We observed that contractility is inhibited by microtubules not only, as previously reported, in adherent cells, but also in non-adhering interphase and mitotic cells. Strikingly we observed that contractility requires ubiquitin mediated proteolysis by a Cullin-RING ubiquitin ligase. Inhibition of proteolysis, ubiquitination and neddylation all led to complete cessation of contractility and considerably reduced MLC Ser19 phosphorylation. CONCLUSIONS: Our results imply that cells express a contractility inhibitor that is degraded by ubiquitin mediated proteolysis, either constitutively or in response to microtubule depolymerization. This degradation seems to depend on a Cullin-RING ubiquitin ligase and is required for cellular contractions.

  13. Cellular and molecular perspectives in rheumatoid arthritis.

    Science.gov (United States)

    Veale, Douglas J; Orr, Carl; Fearon, Ursula

    2017-06-01

    Synovial immunopathology in rheumatoid arthritis is complex involving both resident and infiltrating cells. The synovial tissue undergoes significant neovascularization, facilitating an influx of lymphocytes and monocytes that transform a typically acellular loose areolar membrane into an invasive tumour-like pannus. The microvasculature proliferates to form straight regularly-branching vessels; however, they are highly dysfunctional resulting in reduced oxygen supply and a hypoxic microenvironment. Autoantibodies such as rheumatoid factor and anti-citrullinated protein antibodies are found at an early stage, often before arthritis has developed, and they have been implicated in the pathogenesis of RA. Abnormal cellular metabolism and mitochondrial dysfunction thus ensue and, in turn, through the increased production of reactive oxygen species actively induce inflammation. Key pro-inflammatory cytokines, chemokines and growth factors and their signalling pathways, including nuclear factor κB, Janus kinase-signal transducer, are highly activated when immune cells are exposed to hypoxia in the inflamed rheumatoid joint show adaptive survival reactions by activating. This review attempts to highlight those aberrations in the innate and adaptive immune systems including the role of genetic and environmental factors, autoantibodies, cellular alterations, signalling pathways and metabolism that are implicated in the pathogenesis of RA and may therefore provide an opportunity for therapeutic intervention.

  14. Cellular senescence and the aging brain.

    Science.gov (United States)

    Chinta, Shankar J; Woods, Georgia; Rane, Anand; Demaria, Marco; Campisi, Judith; Andersen, Julie K

    2015-08-01

    Cellular senescence is a potent anti-cancer mechanism that arrests the proliferation of mitotically competent cells to prevent malignant transformation. Senescent cells accumulate with age in a variety of human and mouse tissues where they express a complex 'senescence-associated secretory phenotype' (SASP). The SASP includes many pro-inflammatory cytokines, chemokines, growth factors and proteases that have the potential to cause or exacerbate age-related pathology, both degenerative and hyperplastic. While cellular senescence in peripheral tissues has recently been linked to a number of age-related pathologies, its involvement in brain aging is just beginning to be explored. Recent data generated by several laboratories suggest that both aging and age-related neurodegenerative diseases are accompanied by an increase in SASP-expressing senescent cells of non-neuronal origin in the brain. Moreover, this increase correlates with neurodegeneration. Senescent cells in the brain could therefore constitute novel therapeutic targets for treating age-related neuropathologies. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Simulated Hypergravity Alters Vascular Smooth Muscle Cell Proliferation and Motility

    Science.gov (United States)

    Hunt, Shameka; Bettis, Barika; Harris-Hooker, Sandra; Sanford, Gary L.

    1997-01-01

    The cellular effects of gravity are poorly understood due to its constancy and nonavailability of altered gravitational models. Such an understanding is crucial for prolonged space flights. In these studies, we assessed the influence of centrifugation at 6G (HGrav) on vascular smooth muscle (SMC) mobility and proliferation. Cells were: (a) plated at low density and subjected to HGrav for 24-72 hr for proliferation studies, or (b) grown to confluency, subjected to HGrav, mechanically denuded and monitored for cell movement into the denuded area. Controls were maintained under normogravity. SMC showed a 50% inhibition of growth under HGrav and 10% serum; HGrav and low serum resulted in greater growth inhibition. The rate of movement of SMC into the denuded area was 2-3-fold higher under HGrav in low serum compared to controls, but similar in 10% serum. These studies show that HGrav has significant effects on SMC growth and mobility, which are dependent on serum levels.

  16. Ultrastructure of the mature spermatozoon of Eubothrium rugosum (Batsch, 1786) with a re-assessment of the spermatozoon ultrastructure of Eubothrium crassum (Bloch, 1779) (Cestoda: Bothriocephalidea)

    Czech Academy of Sciences Publication Activity Database

    Bruňanská, M.; Fagerholm, H. P.; Nebesářová, Jana; Kostič, B.

    2010-01-01

    Roč. 47, č. 4 (2010), s. 257-263 ISSN 0440-6605 Institutional research plan: CEZ:AV0Z60220518 Keywords : ultrastructure * spermatozoon * Eubothrium * Bothriocephalidea * Cestoda Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 0.847, year: 2010

  17. [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

  18. Histopathological and ultrastructural effects of Losartan on embryonic rat kidney.

    Science.gov (United States)

    Akil, Ipek; Inan, Sevinc; Gurcu, Beyhan; Nazikoglu, Aysegul; Ozbilgin, Kemal; Muftuoglu, Sevda

    2005-01-01

    The aim of our study was to investigate the histopathological, immunohistochemical and ultrastructural effects of Losartan (a selective angiotensin II type-1 receptor blocker) on renal development in rats. Twelve pregnant rats were divided into control and experimental groups. In the experimental group, Losartan (10 mg/kg/day) was given via nasogastric tube, between the sixth day of implantation and time of sacrifice on embryonic days 18 and 20. All formalin-fixed, paraffin wax-embedded renal tissue sections were stained with hematoxylin and eosin or labelled for binding of primary antibodies against transforming growth factor-beta (TGF-beta 1,-2,-3) using an avidin-biotin-peroxidase method. For electron microscopic examination, samples were fixed with glutaraldehyde and osmium tetroxide and embedded in araldite. Glomerular basement membrane (GBM) thickness was measured and compared using an unpaired t-test. Angiotensin II type-1 receptor antagonism by Losartan inhibited renal growth and delayed nephron maturation. Increased immunoreactivity of TGF-beta's was observed in developing nephron precursors and interstitial cells in the experimental group. Electron microscopical examination showed that thickening of the GBM was normal in the control group but an irregular thickening was seen in the experimental group (p < 0.001). It was also seen that epithelial cells of developing tubules underwent apoptosis in the experimental group. Thus, renal development in rats seems to depend on an intact renin-angiotensin system.

  19. Volume scanning electron microscopy for imaging biological ultrastructure.

    Science.gov (United States)

    Titze, Benjamin; Genoud, Christel

    2016-11-01

    Electron microscopy (EM) has been a key imaging method to investigate biological ultrastructure for over six decades. In recent years, novel volume EM techniques have significantly advanced nanometre-scale imaging of cells and tissues in three dimensions. Previously, this had depended on the slow and error-prone manual tasks of cutting and handling large numbers of sections, and imaging them one-by-one with transmission EM. Now, automated volume imaging methods mostly based on scanning EM (SEM) allow faster and more reliable acquisition of serial images through tissue volumes and achieve higher z-resolution. Various software tools have been developed to manipulate the acquired image stacks and facilitate quantitative analysis. Here, we introduce three volume SEM methods: serial block-face electron microscopy (SBEM), focused ion beam SEM (FIB-SEM) and automated tape-collecting ultramicrotome SEM (ATUM-SEM). We discuss and compare their capabilities, provide an overview of the full volume SEM workflow for obtaining 3D datasets and showcase different applications for biological research. © 2016 Société Française des Microscopies and Société de Biologie Cellulaire de France. Published by John Wiley & Sons Ltd.

  20. Gamma irradiation induced ultrastructural changes in Paracoccidioides brasiliensis yeast cells

    Energy Technology Data Exchange (ETDEWEB)

    Demicheli, Marina C.; Andrade, Antero S.R. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)]. E-mails: marinademicheli@yahoo.com.br; antero@cdtn.br; Goes, Alfredo Miranda [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Bioquimica e Imunologia]. E-mail: goes@mono.icb.ufmg.br

    2007-07-01

    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)

  1. Ultrastructural Modifications of Human Endometrium during the Window of Implantation

    Directory of Open Access Journals (Sweden)

    Maryam Kabir-Salmani

    2008-01-01

    Full Text Available The endometrium is a highly dynamic tissue empowered with the capacity to undergo cyclicdramatic changes in response to ovarian steroid hormones, ultimately aiming to create awindow of receptivity for blastocyst implantation. Intensive research has been performed tounderstand and establish morphological and molecular correlates of embryo implantation.However, it still remains a biological mystery particularly in the human, where ethical andmoral constraints prohibit in vivo testing and the establishment of an ideal in vitro modeling.Rodent models of embryo implantation are largely irrelevant because the process variessignificantly from that in humans. Even among primates, subtle differences exist amongspecies. For maternal preparation of implantation, the endometrial epithelium which issurprisingly hostile towards the embryo implantation, acquires functional status receptiveto blastocyst acceptance during a limited period of cycle days, termed as the ‘window ofimplantation (WOI. This review provides currently available information concernedprimarily with the various ultrastructural modifications of endometrium coordinated withinthe WOI that may signify endometrial receptivity. In the following sections, the dominantfeatures of endometrial differentiation during WOI, including transformations of luminalepithelium, endometrial glands, and stromal decidualization will be discussed from themorphological points of view.

  2. Compartmentalization and ultrastructural alterations induced by chromium in aquatic macrophytes.

    Science.gov (United States)

    Mangabeira, Pedro A; Ferreira, Aluane S; de Almeida, Alex-Alan F; Fernandes, Valéria F; Lucena, Emerson; Souza, Vânia L; dos Santos Júnior, Alberto J; Oliveira, Arno H; Grenier-Loustalot, Marie F; Barbier, Fréderique; Silva, Delmira C

    2011-12-01

    The aim of the present study was to identify the sites of accumulation of Cr in the species of macrophytes that are abundant in the Cachoeira river, namely, Alternanthera philoxeroides, Borreria scabiosoides, Polygonum ferrugineum and Eichhornia crassipes. Plants were grown in nutritive solution supplemented with 0.25 and 50 mg l(-1) of CrCl(3)·6H(2)O. Samples of plant tissues were digested with HNO(3)/HCl in a closed-vessel microwave system and the concentrations of Cr determined using inductively-coupled plasma mass spectrometry (ICP-MS). The ultrastructure of root, stem and leaf tissue was examined using transmission electron microscopy (TEM) and secondary ion mass spectrometry (SIMS) in order to determine the sites of accumulation of Cr and to detect possible alterations in cell organelles induced by the presence of the metal. Chromium accumulated principally in the roots of the four macrophytes (8.6-30 mg kg(-1) dw), with much lower concentrations present in the stems and leaves (3.8-8.6 and 0.01-9.0 mg kg(-1) dw, respectively). Within root tissue, Cr was present mainly in the vacuoles of parenchyma cells and cell walls of xylem and parenchyma. Alterations in the shape of the chloroplasts and nuclei were detected in A. philoxeroides and B. scabiosoides, suggesting a possible application of these aquatic plants as biomarkers from Cr contamination.

  3. Peel Ultrastructure During Developmental Stages of Citrus Sinensis (L. Osbeck.

    Directory of Open Access Journals (Sweden)

    Indira Prabasari

    2014-02-01

    Full Text Available The peel structureof Valencia orange (Citrus sinensis (L. Osbeck was examined using Scanning Electron Microscopy (SEM and showed the distinct regions of the peel: the outer-yellowish part that was called the flavedo and the inner part of the peel that was called the albedo.  The flavedo has compact cells with oil glands embedded in it whereas the albedo contains of spongy cells with vascular bundles embedded in it. The ultrastructural examination of the albedo during development revealed the changes of albedo morphology from compact tissue to the loosely arranged tissue. In addition, the distribution of polysaccharide cell walls was observed with histochemical staining and later the distribution of peptic polysaccharide was conducted using anti-pectin monoclonal antibodies (mAbs. Histochemical staining during development demonstrated the difference of abundance of polysaccharide at the tissue level.  Furthermore, the distribution of homogalacturonan (HG was studied with mAb JIM5 that recognizes low methyl-esterified HG and JJM7 which labels high methyl-esterified HG. The observation at the fruit level was conducted using tissue printing and the result showed that low and high methyl-esterified HG was distributed almost similar at the fruit level. Further experiment at the tissue level was performed using Light Microscopy (LM and revealed that HG was found more abundant in the albedo and vascular bundle followed by the flavedo and oil gland.

  4. Ultrastructural description of rabies virus infection in cultured sensory neurons

    Directory of Open Access Journals (Sweden)

    Myriam L Velandia

    2007-06-01

    Full Text Available Primary cultures were made from adult mouse spinal ganglia for depicting an ultrastructural description of rabies virus (RABV infection in adult mouse sensory neuron cultures; they were infected with rabies virus for 24, 36, and 48 h. The monolayers were processed for transmission electron microscopy and immunochemistry studies at the end of each period. As previously reported, sensory neurons showed great susceptibility to infection by RABV; however, in none of the periods evaluated were assembled virions observed in the cytoplasm or seen to be associated with the cytoplasmic membrane. Instead, fibril matrices of aggregated ribonucleoprotein were detected in the cytoplasm. When infected culture lysate were inoculated into normal animals via intra-cerebral route it was observed that these animals developed clinical symptoms characteristic of infection and transmission electron microscopy revealed assembled virions in the cerebral cortex and other areas of the brain. Sensory neurons infected in vitro by RABV produced a large amount of unassembled viral ribonucleoprotein. However, this intracellular material was able to produce infection and virions on being intra-cerebrally inoculated. It can thus be suggested that the lack of intracellular assembly in sensory neurons forms part of an efficient dissemination strategy.

  5. Ultrastructure of plasma cells in harderian gland of laying hens.

    Science.gov (United States)

    Bejdić, P; Avdić, R; Amidžić, Lj; Ćutahija, V; Tandir, F; Hadžiomerović, N; Katica, A; Mlaćo, N

    2018-02-01

    Ultrastructure of plasma cells in Harderian gland was investigated using the transmission electron microscopy. For this research, we examined the glands of 32 laying hens collected at 1, 7, 20 and 40 days and 4, 6, 8 and 12 months of the birds' ages. The research showed that the stroma of the gland contains a large number of lymphocytes and plasma cells. Most of the plasma cells are mature, but morphologically do not show productive activity. Only some individual plasma cells, situated under the secretory epithelium of primary and secondary ducts, have extremely dilated cisternae of rough endoplasmic reticulum which contain moderately dense, granular material. The morphology of these cells indicates that they are in active stage of immunoglobulin production. Also, we identified plasma cells with two types of Russell bodies. One type of these bodies was small, round or oval, while the other had irregular, angular shape. It was noted that one plasma cell never contains both type of Russell bodies at the same time. These cells were often affected by apoptosis. Among them, in deeper part of the stroma, were situated the small plasmablast cells. © 2017 Blackwell Verlag GmbH.

  6. The Ultrastructural Signature of Human Embryonic Stem Cells.

    Science.gov (United States)

    Underwood, Jean M; Becker, Klaus A; Stein, Gary S; Nickerson, Jeffrey A

    2017-04-01

    The epigenetics and molecular biology of human embryonic stem cells (hES cells) have received much more attention than their architecture. We present a more complete look at hES cells by electron microscopy, with a special emphasis on the architecture of the nucleus. We propose that there is an ultrastructural signature of pluripotent human cells. hES cell nuclei lack heterochromatin, including the peripheral heterochromatin, that is common in most somatic cell types. The absence of peripheral heterochromatin may be related to the absence of lamins A and C, proteins important for linking chromatin to the nuclear lamina and envelope. Lamins A and C expression and the development of peripheral heterochromatin were early steps in the development of embryoid bodies. While hES cell nuclei had abundant nuclear pores, they also had an abundance of nuclear pores in the cytoplasm in the form of annulate lamellae. These were not a residue of annulate lamellae from germ cells or the early embryos from which hES cells were derived. Subnuclear structures including nucleoli, interchromatin granule clusters, and Cajal bodies were observed in the nuclear interior. The architectural organization of human ES cell nuclei has important implications for cell structure-gene expression relationships and for the maintenance of pluripotency. J. Cell. Biochem. 118: 764-774, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Ultrastructure of the platypus and echidna mandibular glands.

    Science.gov (United States)

    Krause, W J

    2011-10-01

    The secretory units of the platypus and echidna mandibular glands consist of a single serous cell type. Secretory granules within the cells of the platypus mandibular gland stained intensely with the periodic acid-Schiff staining procedure but failed to stain with Alcian Blue, suggesting the granules contained neutral glycoproteins. Secretory granules within the mandibular glands of the echidna failed to stain with the methods used indicating little if any glycoprotein was associated with the secretory granules. Ultrastructurally, secretory granules of the platypus mandibular gland were electron dense with a central core of less electron-dense material and were membrane bound. In contrast, those of the echidna presented a lamellated appearance and also were limited by a membrane. These secretory granules appeared to form as a result of concentric layering of lamellae within cisternae of the Golgi membranes. The intralobular ductal system of the platypus was more extensively developed than that of the echidna. The striated ducts of both species were characterized by elaborate infoldings of the basolateral plasmalemma and an abundance of associated mitochondria. © 2011 Blackwell Verlag GmbH.

  8. 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.

  9. The Ultrastructural Relationship Between Osteocytes and Dental Implants Following Osseointegration.

    Science.gov (United States)

    Du, Zhibin; Ivanovski, Saso; Hamlet, Stephen M; Feng, Jian Q; Xiao, Yin

    2016-04-01

    Osteocytes, the most abundant cells in bone, have multiple functions, including acting as mechanosensors and regulating mineralization. It is clear that osteocytes influence bone remodeling by controlling the differentiation and activity of osteoblasts and osteoclasts. Determining the relationship between titanium implants and osteocytes may therefore benefit our understanding of the process of osseointegration. The aim of this study was to visualize the ultrastructural relationship between osteocytes and the titanium implant surface following osseointegration in vivo. Titanium implants were placed in the maxillary molar regions of eight female Sprague Dawley rats, 3 months old. The animals were sacrificed 8 weeks after implantation, and undecalcified tissue sections were prepared. Resin-cast samples were subsequently acid-etched with 37% phosphoric acid prior to examination using scanning electron microscopy. Compared with mature bone, where the osteocytes were arranged in an ordered fashion, the osteocytes appeared less organized in the newly formed bone around the titanium implant. Further, a layer of mineralization with few organic components was observed on the implant surface. This study shows for the first time that osteocytes and their dendrites are directly connected with the implant surface. This study shows the direct anchorage of osteocytes via dendritic processes to a titanium implant surface in vivo. This suggests an important regulatory role for osteocytes and their lacunar-canalicular network in maintaining long-term osseointegration. © 2014 Wiley Periodicals, Inc.

  10. The ultrastructure of bone and its relevance to mechanical properties

    Science.gov (United States)

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

    2017-09-01

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

  11. Horrifying Basal Cell Carcinoma: Cytological, Immunohistochemical, and Ultrastructural Findings

    Directory of Open Access Journals (Sweden)

    Yuichi Kinoshita

    2014-07-01

    Full Text Available Basal cell carcinoma (BCC is a slow-growing and frequently occurring tumor of the eyelids. Among BCC cases, there is a subtype of aggressive cases called horrifying BCC (HBCC. There are also rare BCC cases that show neuroendocrine differentiation. Here, we describe a case of HBCC with neuroendocrine differentiation. The patient, a 41-year-old woman, presented with abnormal left eye tearing and left cheek pain. On computed tomography imaging, a tumor that extended to the left orbit was detected in the left cheek. On cytological examination of fine-needle aspiration (FNA samples, the tumor cells were observed as sheet-like clusters and single bare nuclei with a clear background; peripheral palisading was not clearly seen. On examination of the biopsy specimen taken after FNA, the tumor was found to be composed of cancer cell nests with scattered peripheral palisading in the dermis. Immunohistochemically, the tumor cells were positive for cytokeratin (CK 7 and CD56 and were negative for CK20, synaptophysin, and chromogranin A. Membrane-bound dense-core granules were detected on ultrastructural study. A HBCC case with neuroendocrine differentiation has not been previously reported. The correlation between the presence of neuroendocrine differentiation in HBCC and patient prognosis should be further studied.

  12. Statistical mechanics of cellular automata

    International Nuclear Information System (INIS)

    Wolfram, S.

    1983-01-01

    Cellular automata are used as simple mathematical models to investigate self-organization in statistical mechanics. A detailed analysis is given of ''elementary'' cellular automata consisting of a sequence of sites with values 0 or 1 on a line, with each site evolving deterministically in discrete time steps according to p definite rules involving the values of its nearest neighbors. With simple initial configurations, the cellular automata either tend to homogeneous states, or generate self-similar patterns with fractal dimensions approx. =1.59 or approx. =1.69. With ''random'' initial configurations, the irreversible character of the cellular automaton evolution leads to several self-organization phenomena. Statistical properties of the structures generated are found to lie in two universality classes, independent of the details of the initial state or the cellular automaton rules. More complicated cellular automata are briefly considered, and connections with dynamical systems theory and the formal theory of computation are discussed

  13. Molecular and cellular mechanisms of cadmium carcinogenesis

    International Nuclear Information System (INIS)

    Waisberg, Michael; Joseph, Pius; Hale, Beverley; Beyersmann, Detmar

    2003-01-01

    Cadmium is a heavy metal, which is widely used in industry, affecting human health through occupational and environmental exposure. In mammals, it exerts multiple toxic effects and has been classified as a human carcinogen by the International Agency for Research on Cancer. Cadmium affects cell proliferation, differentiation, apoptosis and other cellular activities. Cd 2+ does not catalyze Fenton-type reactions because it does not accept or donate electrons under physiological conditions, and it is only weakly genotoxic. Hence, indirect mechanisms are implicated in the carcinogenicity of cadmium. In this review multiple mechanisms are discussed, such as modulation of gene expression and signal transduction, interference with enzymes of the cellular antioxidant system and generation of reactive oxygen species (ROS), inhibition of DNA repair and DNA methylation, role in apoptosis and disruption of E-cadherin-mediated cell-cell adhesion. Cadmium affects both gene transcription and translation. The major mechanisms of gene induction by cadmium known so far are modulation of cellular signal transduction pathways by enhancement of protein phosphorylation and activation of transcription and translation factors. Cadmium interferes with antioxidant defense mechanisms and stimulates the production of reactive oxygen species, which may act as signaling molecules in the induction of gene expression and apoptosis. The inhibition of DNA repair processes by cadmium represents a mechanism by which cadmium enhances the genotoxicity of other agents and may contribute to the tumor initiation by this metal. The disruption of E-cadherin-mediated cell-cell adhesion by cadmium probably further stimulates the development of tumors. It becomes clear that there exist multiple mechanisms which contribute to the carcinogenicity of cadmium, although the relative weights of these contributions are difficult to estimate

  14. The depletion of nuclear glutathione impairs cell proliferation in 3t3 fibroblasts.

    Directory of Open Access Journals (Sweden)

    Jelena Markovic

    2009-07-01

    Full Text Available Glutathione is considered essential for survival in mammalian cells and yeast but not in prokaryotic cells. The presence of a nuclear pool of glutathione has been demonstrated but its role in cellular proliferation and differentiation is still a matter of debate.We have studied proliferation of 3T3 fibroblasts for a period of 5 days. Cells were treated with two well known depleting agents, diethyl maleate (DEM and buthionine sulfoximine (BSO, and the cellular and nuclear glutathione levels were assessed by analytical and confocal microscopic techniques, respectively. Both agents decreased total cellular glutathione although depletion by BSO was more sustained. However, the nuclear glutathione pool resisted depletion by BSO but not with DEM. Interestingly, cell proliferation was impaired by DEM, but not by BSO. Treating the cells simultaneously with DEM and with glutathione ethyl ester to restore intracellular GSH levels completely prevented the effects of DEM on cell proliferation.Our results demonstrate the importance of nuclear glutathione in the control of cell proliferation in 3T3 fibroblasts and suggest that a reduced nuclear environment is necessary for cells to progress in the cell cycle.

  15. Nuclear Proliferation Technology Trends Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Zentner, Michael D.; Coles, Garill A.; Talbert, Robert J.

    2005-10-04

    A process is underway to develop mature, integrated methodologies to address nonproliferation issues. A variety of methodologies (both qualitative and quantitative) are being considered. All have one thing in common, a need for a consistent set of proliferation related data that can be used as a basis for application. One approach to providing a basis for predicting and evaluating future proliferation events is to understand past proliferation events, that is, the different paths that have actually been taken to acquire or attempt to acquire special nuclear material. In order to provide this information, this report describing previous material acquisition activities (obtained from open source material) has been prepared. This report describes how, based on an evaluation of historical trends in nuclear technology development, conclusions can be reached concerning: (1) The length of time it takes to acquire a technology; (2) The length of time it takes for production of special nuclear material to begin; and (3) The type of approaches taken for acquiring the technology. In addition to examining time constants, the report is intended to provide information that could be used to support the use of the different non-proliferation analysis methodologies. Accordingly, each section includes: (1) Technology description; (2) Technology origin; (3) Basic theory; (4) Important components/materials; (5) Technology development; (6) Technological difficulties involved in use; (7) Changes/improvements in technology; (8) Countries that have used/attempted to use the technology; (9) Technology Information; (10) Acquisition approaches; (11) Time constants for technology development; and (12) Required Concurrent Technologies.

  16. Salvianolic Acid A Inhibits PDGF-BB Induced Vascular Smooth Muscle Cell Migration and Proliferation While Does Not Constrain Endothelial Cell Proliferation and Nitric Oxide Biosynthesis

    Directory of Open Access Journals (Sweden)

    Chao Huang

    2012-03-01

    Full Text Available Proliferation and migration of vascular smooth muscle cells (VSMCs are critical events in the initiation and development of restenosis upon percutaneous transluminal coronary angioplasty (PTCA. Polyphenols have been suggested to ameliorate post-angioplasty restenosis. Salvianolic A (SalA is one of the most abundant polyphenols extracted from salvia. In this study, we investigated the effect of salvianolic A (SalA on the migration and proliferation of VSMCs. We found a preferential interaction of SalA with cellular systems that rely on the PDGF signal, but not on the EGF and bFGF signal. SalA inhibits PDGF-BB induced VSMC proliferation and migration in the concentration range from 0.01 to 0.1 μM. The inhibition of SalA on VSMC proliferation is associated with cell cycle arrest. We also found that SalA inhibits the PDGFRβ-ERK1/2 signaling cascade activated by PDGF-BB in VSMCs. In addition, SalA does not influence the proliferation of endothelial cells, the synthesis of NO and eNOS protein expression. Our results suggest that SalA inhibits migration and proliferation of VSMCs induced by PDGF-BB via the inhibition of the PDGFRβ-ERK1/2 cascade, but that it does not constrain endothelial cell proliferation and nitric oxide biosynthesis. Thus, the present study suggests a novel adjunct pharmacological strategy to prevent angioplasty-related restenosis.

  17. Aging and atherosclerosis: mechanisms, functional consequences, and potential therapeutics for cellular senescence.

    Science.gov (United States)

    Wang, Julie C; Bennett, Martin

    2012-07-06

    Atherosclerosis is classed as a disease of aging, such that increasing age is an independent risk factor for the development of atherosclerosis. Atherosclerosis is also associated with premature biological aging, as atherosclerotic plaques show evidence of cellular senescence characterized by reduced cell proliferation, irreversible growth arrest and apoptosis, elevated DNA damage, epigenetic modifications, and telomere shortening and dysfunction. Not only is cellular senescence associated with atherosclerosis, there is growing evidence that cellular senescence promotes atherosclerosis. This review examines the pathology of normal vascular aging, the evidence for cellular senescence in atherosclerosis, the mechanisms underlying cellular senescence including reactive oxygen species, replication exhaustion and DNA damage, the functional consequences of vascular cell senescence, and the possibility that preventing accelerated cellular senescence is a therapeutic target in atherosclerosis.

  18. Common Genetic Variation In Cellular Transport Genes and Epithelial Ovarian Cancer (EOC) Risk

    OpenAIRE

    Chornokur, Ganna; Lin, Hui-Yi; Tyrer, Jonathan P.; Lawrenson, Kate; Dennis, Joe; Amankwah, Ernest K.; Qu, Xiaotao; Tsai, Ya-Yu; Jim, Heather S. L.; Chen, Zhihua; Chen, Ann Y.; Permuth-Wey, Jennifer; Aben, Katja KH.; Anton-Culver, Hoda; Antonenkova, Natalia

    2015-01-01

    Background\\ud \\ud Defective cellular transport processes can lead to aberrant accumulation of trace elements, iron, small molecules and hormones in the cell, which in turn may promote the formation of reactive oxygen species, promoting DNA damage and aberrant expression of key regulatory cancer genes. As DNA damage and uncontrolled proliferation are hallmarks of cancer, including epithelial ovarian cancer (EOC), we hypothesized that inherited variation in the cellular transport genes contribu...

  19. The ultrastructure of book lung development in the bark scorpion Centruroides gracilis (Scorpiones: Buthidae

    Directory of Open Access Journals (Sweden)

    Farley Roger D

    2011-07-01

    Full Text Available Abstract Background Near the end of the nineteenth century the hypothesis was presented for the homology of book lungs in arachnids and book gills in the horseshoe crab. Early studies with the light microscope showed that book gill lamellae are formed by outgrowth and possibly some invagination (infolding of hypodermis (epithelium from the posterior surface of opisthosomal limb buds. Scorpion book lungs are formed near the bilateral sites of earlier limb buds. Hypodermal invaginations in the ventral opisthosoma result in spiracles and sac-like cavities (atria. In early histological sections of embryo book lungs, widening of the atrial entrance of some lamellae (air channels, air sacs, saccules was interpreted as an indication of invagination as hypothesized for book gill lamellae. The hypodermal infolding was thought to produce the many rows of lamellar precursor cells anterior to the atrium. The ultrastructure of scorpion book lung development is compared herein with earlier investigations of book gill formation. Results In scorpion embryos, there is ingression (inward migration of atrial hypodermal cells rather than invagination or infolding of the atrial hypodermal layer. The ingressing cells proliferate and align in rows anterior to the atrium. Their apical-basal polarity results in primordial air channels among double rows of cells. The cuticular walls of the air channels are produced by secretion from the apical surfaces of the aligned cells. Since the precursor cells are in rows, their secreted product is also in rows (i.e., primordial air channels, saccules. For each double row of cells, their opposed basal surfaces are gradually separated by a hemolymph channel of increasing width. Conclusions The results from this and earlier studies show there are differences and similarities in the formation of book lung and book gill lamellae. The homology hypothesis for these respiratory organs is thus supported or not supported depending on which

  20. Primary synovial sarcomas of the mediastinum: a clinicopathologic, immunohistochemical, and ultrastructural study of 15 cases.

    Science.gov (United States)

    Suster, Saul; Moran, Cesar A

    2005-05-01

    A series of 15 cases of primary mediastinal neoplasms displaying histopathologic, immunohistochemical, and ultrastructural features of synovial sarcoma is presented. The patients' ages ranged from 3 to 83 years, with a male-to-female ratio of 2:1. Nine cases presented as anterior mediastinal masses with chest pain, shortness of breath, and pleural effusion, and 6 cases were in paravertebral location in the posterior mediastinum and presented with neck or back pain and pleural effusion. The tumors measured from 5 to 20 cm in greatest diameter and showed a tan white, soft to rubbery cut surface with areas of hemorrhage and necrosis and foci of gelatinous material. Four cases showed areas of cystic degeneration. In 7 cases, the tumors were well circumscribed; in 6 cases, the tumors grossly invaded the pleura, pericardium, heart, great vessels, chest wall, rib, and vertebra. Histologically, 5 cases displayed a biphasic growth pattern, with well-formed glandular elements admixed with a monotonous spindle cell population. Ten cases were exclusively composed of a monotonous atypical spindle cell proliferation. Immunohistochemical studies showed focal positivity of the tumor cells for cytokeratin and/or epithelial membrane antigen, and strong positivity for vimentin and bcl-2 in the spindle cells in all cases studied (10 of 10). Eight cases also showed focal positivity for CD99. Electron microscopic examination in 5 cases showed oval to spindle tumor cells with closely apposed cell membranes, abundant cytoplasmic intermediate filaments and rough endoplasmic reticulum, and immature desmosome-type cell junctions. Ten patients were treated by complete surgical excision and two by partial excision followed by radiation therapy. In 4 patients, the tumors were inoperable and treated with radiation therapy only. Clinical follow-up was available in 5 patients and showed local recurrence with metastases to lung, lymph nodes, and epidural space from 1 to 3 years in 4 cases and liver

  1. Highly efficient mesenchymal stem cell proliferation on poly-ε-caprolactone nanofibers with embedded magnetic nanoparticles

    Science.gov (United States)

    Daňková, Jana; Buzgo, Matej; Vejpravová, Jana; Kubíčková, Simona; Sovková, Věra; Vysloužilová, Lucie; Mantlíková, Alice; Nečas, Alois; Amler, Evžen

    2015-01-01

    In this study, we have developed a combined approach to accelerate the proliferation of mesenchymal stem cells (MSCs) in vitro, using a new nanofibrous scaffold made by needleless electrospinning from a mixture of poly-ε-caprolactone and magnetic particles. The biological characteristics of porcine MSCs were investigated while cultured in vitro on composite scaffold enriched with magnetic nanoparticles. Our data indicate that due to the synergic effect of the poly-ε-caprolactone nanofibers and magnetic particles, cellular adhesion and proliferation of MSCs is enhanced and osteogenic differentiation is supported. The cellular and physical attributes make this new scaffold very promising for the acceleration of efficient MSC proliferation and regeneration of hard tissues. PMID:26677321

  2. Tigecycline inhibits proliferation of Acanthamoeba castellanii.

    Science.gov (United States)

    Jha, Bijay Kumar; Seo, Incheol; Kong, Hyun-Hee; Suh, Seong-Il; Suh, Min-Ho; Baek, Won-Ki

    2015-03-01

    Acanthamoeba is an opportunistic protozoan parasite responsible for different diseases in humans, such as granulomatous amoebic encephalitis and amoebic keratitis. Tigecycline, a third-generation tetracycline antibiotic, has potential activity to treat most of the antibiotic resistant bacterial infections. The effects of tigecycline in eukaryotic cells as well as parasites are less well studied. In the present study, we tested the effects of tigecycline on trophozoites of Acanthamoeba castellanii. The inhibitory effect of tigecycline on Acanthamoeba was determined by resazurin reduction and trypan blue exclusion assays. We found that tigecycline significantly inhibited the growth of Acanthamoeba (46.4 % inhibition at the concentration of 100 μM) without affecting cell viability and induction of encystation, whereas other tetracycline groups of antibiotics such as tetracycline and doxycycline showed no inhibitory effects. Furthermore, tigecycline decreased cellular adenosine triphosphate (ATP) level by 26 % than the control and increased mitochondrial mass, suggesting mitochondrial dysfunction in tigecycline-treated cells. These findings suggest that mitochondrial dysfunction with decreased ATP production might play an important mechanism of tigecycline in suppression of Acanthamoeba proliferation.

  3. Clustering nuclear receptors in liver regeneration identifies candidate modulators of hepatocyte proliferation and hepatocarcinoma.

    Directory of Open Access Journals (Sweden)

    Michele Vacca

    Full Text Available Liver regeneration (LR is a valuable model for studying mechanisms modulating hepatocyte proliferation. Nuclear receptors (NRs are key players in the control of cellular functions, being ideal modulators of hepatic proliferation and carcinogenesis.We used a previously validated RT-qPCR platform to profile modifications in the expression of all 49 members of the NR superfamily in mouse liver during LR. Twenty-nine NR transcripts were significantly modified in their expression during LR, including fatty acid (peroxisome proliferator-activated receptors, PPARs and oxysterol (liver X receptors, Lxrs sensors, circadian masters RevErbα and RevErbβ, glucocorticoid receptor (Gr and constitutive androxane receptor (Car. In order to detect the NRs that better characterize proliferative status vs. proliferating liver, we used the novel Random Forest (RF analysis to selected a trio of down-regulated NRs (thyroid receptor alpha, Trα; farsenoid X receptor beta, Fxrβ; Pparδ as best discriminators of the proliferating status. To validate our approach, we further studied PPARδ role in modulating hepatic proliferation. We first confirmed the suppression of PPARδ both in LR and human hepatocellular carcinoma at protein level, and then demonstrated that PPARδ agonist GW501516 reduces the proliferative potential of hepatoma cells.Our data suggest that NR transcriptome is modulated in proliferating liver and is a source of biomarkers and bona fide pharmacological targets for the management of liver disease affecting hepatocyte proliferation.

  4. Ultrastructure of the spermatozoon of the digenean Plagiorchis elegans (Rudolphi, 1802) (Plagiorchioidea, Plagiorchiidae).

    Science.gov (United States)

    Ndiaye, Papa Ibnou; Quilichini, Yann; Tkach, Vasyl V; Greiman, Stephen E; Bâ, Cheikh Tidiane; Marchand, Bernard

    2013-09-01

    The ultrastructure of the mature spermatozoon of the type genus of the Plagiorchiidae Plagiorchis elegans (Rudolphi, 1802), a parasite of the Golden hamster, Mesocricetus auratus is described. This study is the first ultrastructural study of the spermatozoon of a Plagiorchis, the second of a plagiorchiid species and only the third in the Plagiorchioidea. Previously data on spermatozoon ultrastructure existed only for the plagiorchiid Enodiotrema reductum and the omphalometrid Rubenstrema exasperatum. The mature spermatozoon of P. elegans exhibited the general pattern described in most digenean species, namely two axonemes of the 9 + "1" Trepaxonemata pattern, nucleus, mitochondria, external ornamentation of the plasma membrane, spine-like bodies, and glycogen granules. However, the rather typical expansion of the plasma membrane is not found in P. elegans. Another peculiarity of the spermatozoon of P. elegans is the presence of a structure called thin cytoplasm termination. Spermatozoon ultrastructure of P. elegans is compared with that of E. reductum and R. exasperatum. Spermatozoon of P. elegans conforms to the general pattern described in E. reductum. Thus, this study further expands our knowledge on the spermatozoon ultrastructure among the members of the Plagiorchioidea, one of the most phylogenetically derived groups of the digenea. Copyright © 2013 Wiley Periodicals, Inc.

  5. Sun and shade leaves? Cuticle ultrastructure of Jurassic Komlopteris nordenskioeldii (Nathorst) Barbacka.

    Science.gov (United States)

    Guignard, G; Bóka, K; Barbacka, M

    2001-04-01

    An ultrastructural transmission electron microscope (TEM) study of fossil leaf cuticles from the Jurassic pteridosperm Komlopteris nordenskioeldii (Nathorst) Barbacka from the Mecsek Mountains (South Hungary) was conducted. Remnants of cuticles of leaves originating from so-called "sun and shade" environments were sectioned with a diamond knife, transversally as well as longitudinally. Although the present study showed a simple type of cuticle in this pteridosperm, differences were observed in the occurrence of its components, such as electron lucent amorphous material and various densities of granules, which give rise to different zones. The included fibrilous elements appeared to be made of aggregated and aligned granules, equivalent in size and electron density to nearby non-fibrilous granular regions. The combinations of these ultrastructural features allow distinctions between four types of cuticle: sun upper, sun lower, shade upper and shade lower. Considering the distinction made earlier in two types of cuticle and supposed to be related to sun and shade on the basis of macroscopical and microscopical features, four types only on the basis of differences in thickness, the present study reinforces the distinctions with ultrastructural microcharacteristics. As this study shows the variations in ultrastructure of cuticle among the four types, the differences observed may reveal the great sensitivity of some plants to environment. At the same time, it points out the importance, in ultrastructural studies of cuticles, of studying a number of samples for one taxon.

  6. Ultrastructural changes in the third-stage, infective larvae of ruminant nematodes treated with sainfoin (Onobrychis viciifolia) extract.

    Science.gov (United States)

    Brunet, S; Fourquaux, I; Hoste, H

    2011-12-01

    Plants rich in condensed tannins are an alternative to chemical anthelmintics to control gastrointestinal nematodes (GINs) in ruminants. Previous functional studies have shown that sainfoin extracts affect the two forms of infective larvae (L3), ensheathed and exsheathed. However, the mechanisms of action remain unknown. The aim of this study was thus to compare ultrastructural changes in ensheathed and exsheathed L3 of two GIN species after in vitro contact with sainfoin extracts using transmission electron microscopy. The main changes identified were an alteration of the hypodermis, the presence of numerous vesicles in the cytoplasm and degeneration and/or death of muscular and intestinal cells. The changes suggested similar and nonspecies-specific lesions in the two nematode species. Comparison of the modifications found in the ensheathed vs. exsheathed L3s revealed different locations of the main cellular changes depending on the larval form. It is hypothesized that these spatial differences in lesions are mainly influenced by the presence of the sheath which favors contact between the active compounds and either the cuticle or the digestive tract. Overall, our observations suggest that the functional changes observed in the biology of GIN L3s after contact with sainfoin extracts are mediated through a direct mode of action, i.e. different interactions between the bioactive plant metabolites and the nematode structure depending on the route of contact. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  7. Ultrastructural proof of polyomavirus in Merkel cell carcinoma tumour cells and its absence in small cell carcinoma of the lung.

    Directory of Open Access Journals (Sweden)

    Charlotte T A H Wetzels

    Full Text Available BACKGROUND: A new virus called the Merkel Cell Polyomavirus (MCPyV has recently been found in Merkel Cell Carcinoma (MCC. MCC is a rare aggressive small cell neuroendocrine carcinoma primarily derived from the skin, morphologically indistinguishable from small cell lung carcinoma (SCLC. So far the actual presence of the virus in MCC tumour cells on a morphological level has not been demonstrated, and the presence of MCPyV in other small cell neuroendocrine carcinomas has not been studied yet. METHODOLOGY/PRINCIPAL FINDINGS: We investigated MCC tissue samples from five patients and SCLCs from ten patients for the presence of MCPyV-DNA by PCR and sequencing. Electron microscopy was used to search ultrastructurally for morphological presence of the virus in MCPyV-DNA positive samples. MCPyV was detected in two out of five primary MCCs. In one MCC patient MCPyV-DNA was detected in the primary tumour as well as in the metastasis, strongly suggesting integration of MCPyV in the cellular DNA of the tumour in this patient. In the primary MCC of another patient viral particles in tumour cell nuclei and cytoplasm were identified by electron microscopy, indicating active viral replication in the tumour cells. In none of the SCLCs MCPyV-DNA was detected. CONCLUSIONS/SIGNIFICANCE: Our results strongly suggest that MCPyV is an oncogenic polyomavirus in humans, and is potentially causally related to the development of MCC but not to the morphological similar SCLC.

  8. Effects of 7-hydroxycalamenene isolated from Croton cajucara essential oil on growth, lipid content and ultrastructural aspects of Rhizopus oryzae.

    Science.gov (United States)

    Azevedo, Mariana M B; Almeida, Catia A; Chaves, Francisco C M; Campos-Takaki, Galba M; Rozental, Sonia; Bizzo, Humberto R; Alviano, Celuta S; Alviano, Daniela S

    2014-05-01

    The leaves and bark of Croton cajucara, a shrub from the Amazon region, have been used in folk medicine to treat diabetes, malaria, and gastrointestinal and liver disorders. The essential oil from the leaves, rich in linalool, presented antileishmanial and antimicrobial activities. A chemotype of this species was found with an essential oil rich in 7-hydroxycalamenene. During our studies of the C. cajucara essential oil, we isolated 7-hydroxycalamenene at > 98 % purity. The minimum inhibitory concentration of 7-hydroxycalamenene against Absidia cylindrospora, Cunninghamella elegans, Mucor circinelloides, Mucor circinelloides f. circinelloides, Mucor mucedo, Mucor plumbeus, Mucor ramosissimus, Rhizopus microsporus, Rhizopus oryzae, and Syncephalastrum racemosum ranged from 19.53 to 2500 µg/mL. The reference drug used, amphotericin B, presented a minimum inhibitory concentration ranging from 0.085 µg/mL to 43.87 µg/mL. 7-Hydroxycalamenene also altered spore differentiation and total lipid content. Ultrastructural analysis by transmission electron microscopy showed significant alterations in the cellular structure of R. oryzae. Georg Thieme Verlag KG Stuttgart · New York.

  9. Pigment epithelium-derived factor up-regulation induced by memantine, an N-methyl-D-aspartate receptor antagonist, is involved in increased proliferation of hippocampal progenitor cells.

    Science.gov (United States)

    Namba, T; Yabe, T; Gonda, Y; Ichikawa, N; Sanagi, T; Arikawa-Hirasawa, E; Mochizuki, H; Kohsaka, S; Uchino, S

    2010-05-05

    Memantine is classified as an NMDA receptor antagonist. We recently reported that memantine promoted the proliferation of neural progenitor cells and the production of mature granule neurons in the adult hippocampus. However, the molecular mechanism responsible for the memantine-induced promotion of cellular proliferation remains unknown. In this study we searched for a factor that mediates memantine-induced cellular proliferation, and found that pigment epithelium-derived factor (PEDF), a broad-acting neurotrophic factor, is up-regulated in the dentate gyrus of adult mice after the injection of memantine. PEDF mRNA expression increased significantly by 3.5-fold at 1 day after the injection of memantine. In addition, the expression level of PEDF protein also increased by 1.8-fold at 2 days after the injection of memantine. Immunohistochemical study using anti-PEDF antibody showed that the majority of the PEDF-expressing cells were protoplasmic and perivascular astrocytes. Using a neurosphere assay, we confirmed that PEDF enhanced cellular proliferation under the presence of fibroblast growth factor-2 (FGF-2) and epidermal growth factor (EGF) but was not involved in the multilineage potency of hippocampal progenitor cells. Over expression of PEDF by adeno-associated virus, however, did not stimulate cellular proliferation, suggesting PEDF per se does not promote cellular proliferation in vivo. These findings suggest that the memantine induced PEDF up-regulation is involved in increased proliferation of hippocampal progenitor cells. (c) 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

  10. Septal Pore Caps in Basidiomycetes, Composition and Ultrastructure

    NARCIS (Netherlands)

    Driel, K.G.A. van

    2007-01-01

    Filamentous fungi, including Ascomycota and Basidiomycota, form mycelia that consist of a network of apical growing hyphae. These hyphae are separated into cellular compartments by septa that have pores of about 70 to 500 nm in diameter. The cytoplasm within the mycelium is thus continuous

  11. MSAT and cellular hybrid networking

    Science.gov (United States)

    Baranowsky, Patrick W., II

    Westinghouse Electric Corporation is developing both the Communications Ground Segment and the Series 1000 Mobile Phone for American Mobile Satellite Corporation's (AMSC's) Mobile Satellite (MSAT) system. The success of the voice services portion of this system depends, to some extent, upon the interoperability of the cellular network and the satellite communication circuit switched communication channels. This paper will describe the set of user-selectable cellular interoperable modes (cellular first/satellite second, etc.) provided by the Mobile Phone and described how they are implemented with the ground segment. Topics including roaming registration and cellular-to-satellite 'seamless' call handoff will be discussed, along with the relevant Interim Standard IS-41 Revision B Cellular Radiotelecommunications Intersystem Operations and IOS-553 Mobile Station - Land Station Compatibility Specification.

  12. MIMO Communication for Cellular Networks

    CERN Document Server

    Huang, Howard; Venkatesan, Sivarama

    2012-01-01

    As the theoretical foundations of multiple-antenna techniques evolve and as these multiple-input multiple-output (MIMO) techniques become essential for providing high data rates in wireless systems, there is a growing need to understand the performance limits of MIMO in practical networks. To address this need, MIMO Communication for Cellular Networks presents a systematic description of MIMO technology classes and a framework for MIMO system design that takes into account the essential physical-layer features of practical cellular networks. In contrast to works that focus on the theoretical performance of abstract MIMO channels, MIMO Communication for Cellular Networks emphasizes the practical performance of realistic MIMO systems. A unified set of system simulation results highlights relative performance gains of different MIMO techniques and provides insights into how best to use multiple antennas in cellular networks under various conditions. MIMO Communication for Cellular Networks describes single-user,...

  13. AMPK-sensitive cellular transport.

    Science.gov (United States)

    Dërmaku-Sopjani, Miribane; Abazi, Sokol; Faggio, Caterina; Kolgeci, Jehona; Sopjani, Mentor

    2014-03-01

    The energy sensing AMP-activated protein kinase (AMPK) regulates cellular and whole-body energy balance through stimulating catabolic ATP-generating and suppressing anabolic ATP-consuming pathways thereby helping cells survive during energy depletion. The kinase has previously been reported to be either directly or indirectly involved in the regulation of several carriers, channels and pumps of high significance in cellular physiology. Thus AMPK provides a necessary link between cellular energy metabolism and cellular transport activity. Better understanding of the AMPK role in cellular transport offers a potential for improved therapies in various human diseases and disorders. In this review, we discuss recent advances in understanding the role and function of AMPK in transport regulation under physiological and pathological states.

  14. Cellular automata analysis and applications

    CERN Document Server

    Hadeler, Karl-Peter

    2017-01-01

    This book focuses on a coherent representation of the main approaches to analyze the dynamics of cellular automata. Cellular automata are an inevitable tool in mathematical modeling. In contrast to classical modeling approaches as partial differential equations, cellular automata are straightforward to simulate but hard to analyze. In this book we present a review of approaches and theories that allow the reader to understand the behavior of cellular automata beyond simulations. The first part consists of an introduction of cellular automata on Cayley graphs, and their characterization via the fundamental Cutis-Hedlund-Lyndon theorems in the context of different topological concepts (Cantor, Besicovitch and Weyl topology). The second part focuses on classification results: What classification follows from topological concepts (Hurley classification), Lyapunov stability (Gilman classification), and the theory of formal languages and grammars (Kůrka classification). These classifications suggest to cluster cel...

  15. Gene expression and ultrastructure of meso- and thermophilic methanotrophic consortia.

    Science.gov (United States)

    Krukenberg, Viola; Riedel, Dietmar; Gruber-Vodicka, Harald R; Buttigieg, Pier Luigi; Tegetmeyer, Halina E; Boetius, Antje; Wegener, Gunter

    2018-02-22

    The sulfate-dependent, anaerobic oxidation of methane (AOM) is an important sink for methane in marine environments. It is carried out between anaerobic methanotrophic archaea (ANME) and sulfate-reducing bacteria (SRB) living in syntrophic partnership. In this study, we compared the genomes, gene expression patterns and ultrastructures of three phylogenetically different microbial consortia found in hydrocarbon-rich environments under different temperature regimes: ANME-1a/HotSeep-1 (60°C), ANME-1a/Seep-SRB2 (37°C) and ANME-2c/Seep-SRB2 (20°C). All three ANME encode a reverse methanogenesis pathway: ANME-2c encodes all enzymes, while ANME-1a lacks the gene for N5,N10-methylene tetrahydromethanopterin reductase (mer) and encodes a methylenetetrahydrofolate reductase (Met). The bacterial partners contain the genes encoding the canonical dissimilatory sulfate reduction pathway. During AOM, all three consortia types highly expressed genes encoding for the formation of flagella or type IV pili and/or c-type cytochromes, some predicted to be extracellular. ANME-2c expressed potentially extracellular cytochromes with up to 32 hemes, whereas ANME-1a and SRB expressed less complex cytochromes (≤8 and ≤12 heme, respectively). The intercellular space of all consortia showed nanowire-like structures and heme-rich areas. These features are proposed to enable interspecies electron exchange, hence suggesting that direct electron transfer is a common mechanism to sulfate-dependent AOM, and that both partners synthesize molecules to enable it. This article is protected by copyright. All rights reserved. © 2018 Society for Applied Microbiology and John Wiley & Sons Ltd.

  16. Spermatozoon ultrastructure and semen parameters of Brycon vermelha (Characiformes, Characidae).

    Science.gov (United States)

    Faustino, F; Silva, R C; Hilbig, C C; Makino, L C; Senhorini, J A; Ninhaus-Silveira, A; Nakaghi, L S O

    2015-06-01

    This study analyzed semen parameters and the ultrastructure of spermatozoa of Brycon vermelha. The semen was white and viscous, with a mean volume of 5.0±2.6 mL/kg body weight and mean spermatozoon concentration of 4.3±0.8×10(10) spermatozoa/mL. The estimated motility rate was 90%, with 50% of spermatozoa motile at 35.0±0.1 s and 100% immotile by 46.5±0.1 s. The spermatozoon of B. vermelha had a distinct head, midpiece, and flagellum. The ovoid head measured 1.9±0.2 μm by 1.3±0.1 μm, with its volume almost completely occupied by the nucleus, and was enveloped by an irregular nuclear membrane, with no acrosome vesicle. The nuclear fossa held the centriole complex and the initial segment of flagellum. The midpiece was symmetrical and measured 1.3±0.3μm. Mitochondria were scarce and restricted to the anterior region, while vesicles were absent. The posterior region of the midpiece was characterized by the absence of mitochondria and the presence of the cytoplasmic sheath. The flagellum, enclosed by the flagellar membrane, measured 29.6±3.4 μm, and possessed an axial filament containing a 9+2 microtubule pattern. The spermatozoa of B. vermelha appeared similar in structure to those of fish that breed through external fertilization, thus classifying them as uniflagellate anacrosomal aquasperm, or Type 1 aquasperm. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. 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.

  18. Synaptic ultrastructure changes in trigeminocervical complex posttrigeminal nerve injury.

    Science.gov (United States)

    Park, John; Trinh, Van Nancy; Sears-Kraxberger, Ilse; Li, Kang-Wu; Steward, Oswald; Luo, Z David

    2016-02-01

    Trigeminal nerves collecting sensory information from the orofacial area synapse on second-order neurons in the dorsal horn of subnucleus caudalis and cervical C1/C2 spinal cord (Vc/C2, or trigeminocervical complex), which is critical for sensory information processing. Injury to the trigeminal nerves may cause maladaptive changes in synaptic connectivity that plays an important role in chronic pain development. Here we examined whether injury to the infraorbital nerve, a branch of the trigeminal nerves, led to synaptic ultrastructural changes when the injured animals have developed neuropathic pain states. Transmission electron microscopy was used to examine synaptic profiles in Vc/C2 at 3 weeks postinjury, corresponding to the time of peak behavioral hypersensitivity following chronic constriction injury to the infraorbital nerve (CCI-ION). Using established criteria, synaptic profiles were classified as associated with excitatory (R-), inhibitory (F-), and primary afferent (C-) terminals. Each type was counted within the superficial dorsal horn of the Vc/C2 and the means from each rat were compared between sham and injured animals; synaptic contact length was also measured. The overall analysis indicates that rats with orofacial pain states had increased numbers and decreased mean synaptic length of R-profiles within the Vc/C2 superficial dorsal horn (lamina I) 3 weeks post-CCI-ION. Increases in the number of excitatory synapses in the superficial dorsal horn of Vc/C2 could lead to enhanced activation of nociceptive pathways, contributing to the development of orofacial pain states. © 2015 Wiley Periodicals, Inc.

  19. Enamel ultrastructure in fossil cetaceans (Cetacea: Archaeoceti and Odontoceti.

    Directory of Open Access Journals (Sweden)

    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

  20. 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

  1. Non proliferation of nuclear weapons?

    International Nuclear Information System (INIS)

    Le Guelte, Georges

    2015-10-01

    After having evoked the behaviour of nuclear countries regarding the development of nuclear weapons and uranium procurement, or nuclear programmes after the Second World War until nowadays, the author presents the non proliferation Treaty (NPT) as a construction at the service of super-powers. He comments and discusses the role of the IAEA control system and its evolutions: a control limited to declared installations, an export control with the spectre of plutonium, a control system thwarted by some technological innovations, information systems coming in, and an additional protocol related to the application of guarantees. He comments the evolution of the context from a bipolar world to a world without pole which raises the issue of how to have commitments respected: description of the role and practice of non proliferation during the Cold War, after the Cold War, and in a world without governance

  2. Proliferation Vulnerability Red Team report

    Energy Technology Data Exchange (ETDEWEB)

    Hinton, J.P.; Barnard, R.W.; Bennett, D.E. [and others

    1996-10-01

    This report is the product of a four-month independent technical assessment of potential proliferation vulnerabilities associated with the plutonium disposition alternatives currently under review by DOE/MD. The scope of this MD-chartered/Sandia-led study was limited to technical considerations that could reduce proliferation resistance during various stages of the disposition processes below the Stored Weapon/Spent Fuel standards. Both overt and covert threats from host nation and unauthorized parties were considered. The results of this study will be integrated with complementary work by others into an overall Nonproliferation and Arms Control Assessment in support of a Secretarial Record of Decision later this year for disposition of surplus U.S. weapons plutonium.

  3. Ultrastructural changes in biofilm forms of staphylococci cultivated in a mixed culture with lactobacilli

    Directory of Open Access Journals (Sweden)

    G. Lavryk

    2017-02-01

    Full Text Available The capacity of opportunistic bacteria for biofilm formation plays an important role in the development of chronic inflammatory processes, which are difficult to treat. To improve antimicrobial therapy methods, the influence of lactobacilli on the ultrastructure of biofilm-forming clinical strains of staphylococci when co-cultured was investigated. 5 biofilm-forming clinical strains of S. aureus from the skin of acne vulgaris patients (n = 24 were isolated. Using transmission electron microscopy (TEM the morphological changes of S. aureus cells in the mixed culture with standard strains of Lactobacillus plantarum 8P-A3 and clinical strains of L. fermentum (n = 4 were studied. It was found that in 48 hours after the inoculation on the medium of samples of mixed cultures of L. plantarum 8P-A3 and S. aureus growth of staphylococci was not revealed. Only in some cases of mixed cultures of L. fermentum and biofilm-forming staphylococci was growth of S. aureus obtained. In electron diffraction patterns of control samples of 24-hour staphylococcal monocultures and 48-hour lactobacilli monocultures, natural development of the population at the cellular level was observed. Destructive changes under the influence of lactobacilli (probiotic and clinical strains were detected in all ultrathin sections of the cells of biofilm-forming and planktonic staphylococci. Significant destructive changes in the cell wall of the staphylococci were observed: thickening, obtaining of irregular form, detachment of the cytoplasmic membrane, the complete destruction of the peptidoglycan layer and the emergence of "shadow cells". On all electron diffraction patterns fibrillar-threadlike structures of DNA could not be observed, but in some cases mesosome-like formations were poorly contrasted. It was established that the surface S-layer of lactobacilli was expressed on a significantly larger scale in the mixed culture with staphylococci. In mixed culture of clinical strains

  4. 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

    , 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...... each kidney from the surface to the inner stripe of the outer zone of medulla. All tubules were reconstructed in 3D and visualized by interactive computer graphics. A quantitative ultrastructural analysis of the mouse proximal tubule at every 300 to 400 micro m was performed. The 3D representation....... 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...

  5. 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.

  6. Spermatozoon ultrastructure of Gyliauchen sp. (Digenea: Gyliauchenidae), an intestinal parasite of Siganus fuscescens (Pisces: Teleostei).

    Science.gov (United States)

    Quilichini, Y; Foata, J; Justine, J-L; Bray, R A; Marchand, B

    2011-10-01

    The ultrastructure of the mature spermatozoon of Gyliauchen sp., a parasite of the dusky rabbitfish Siganus fuscescens, was studied by transmission electron microscopy. The spermatozoon possesses two axonemes of the 9+"1" pattern of Trepaxonemata, four attachment zones, one mitochondrion, a nucleus, cortical microtubules, external ornamentation of the plasma membrane, and spine-like bodies. The main characteristics of this spermatozoon are the presence of one mitochondrion, spine-like bodies not associated with the external ornamentation, and a posterior extremity of type 3 that is characterized by the following sequence: posterior extremity of the nucleus then posterior extremity of the second axoneme. Numerous other ultrastructural features are also discussed and compared to the digenean spermatology literature. This is the first study of a member of the Gyliauchenidae and the fourth within the Lepocreadioidea. The results show that many ultrastructural characters are variable within this superfamily and could be useful for phylogeny.

  7. Ultrastructure of the midgut in Heteroptera (Hemiptera) with different feeding habits.

    Science.gov (United States)

    Santos, Helen Pinto; Rost-Roszkowska, Magdalena; Vilimova, Jitka; Serrão, José Eduardo

    2017-07-01

    Heteroptera have diverse feeding habits with phytophagous, zoophagous, and haematophagous species. This dietary diversity associated with the monophyly of Heteroptera makes these insects a good object for comparative studies of the digestive tract. This work compares the ultrastructure of the middle midgut region in the phytophagous Coptosoma scutellatum (Plataspidae), Graphosoma lineatum (Pentatomidae), Kleidocerys resedae (Lygaeidae), and zoophagous Rhynocoris iracundus (Reduviidae), Nabis rugosus (Nabidae), and Himacerus apterus (Nabidae), to verify if diet affects midgut cells in phylogenetically related insects. The middle region of the midgut was used for comparison because it is the main site for digestion and absorption of the midgut. The digestive cell ultrastructure was similar in the six species, with features of secretory, absorptive, transport, storage, and excretory cells, suggesting a stronger correlation of middle digestive cell ultrastructure with the phylogeny of these species than with the different heteropteran feeding habits.

  8. Russia’s Proliferation Pathways

    Science.gov (United States)

    2009-01-01

    governments who suspected what was going on but looked the other way. Thus his operation confirms the necessity of foreign help for governmental ...was riddled with gangland hits as the state tried to take it over but is possibilities for corruption have not abated. Rather since government and...officials or for the government to arrange a covert and possibly corrupt sale or transfer of nuclear technologies to proliferators using the channels of

  9. Nuclear Proliferation: A Historical Overview

    Science.gov (United States)

    2008-03-01

    enrichment equipment. In 1980 the first uranium enrichment demonstration facility became operational at the Kahuta Research Laboratories ( KRL ). This...Northwest National Laboratory, PNNL-14480 (September 2005), p. 24. 1976: Kahuta Research Laboratories ( KRL ) was established and given the exclusive task...operational at KRL . See M. D. Zentner, G. L. Coles, and R. J. Talbert, “Nuclear Proliferation Technology Trends Analysis,” Pacific Northwest National

  10. Differences in proliferation rate between CADASIL and control vascular smooth muscle cells are related to increased TGFβ expression.

    Science.gov (United States)

    Panahi, Mahmod; Yousefi Mesri, Naeimeh; Samuelsson, Eva-Britt; Coupland, Kirsten G; Forsell, Charlotte; Graff, Caroline; Tikka, Saara; Winblad, Bengt; Viitanen, Matti; Karlström, Helena; Sundström, Erik; Behbahani, Homira

    2018-03-13

    Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a familial fatal progressive degenerative disorder. One of the pathological hallmarks of CADASIL is a dramatic reduction of vascular smooth muscle cells (VSMCs) in cerebral arteries. Using VSMCs from the vasculature of the human umbilical cord, placenta and cerebrum of CADASIL patients, we found that CADASIL VSMCs had a lower proliferation rate compared to control VSMCs. Exposure of control VSMCs and endothelial cells (ECs) to media derived from CADASIL VSMCs lowered the proliferation rate of all cells examined. By quantitative RT-PCR analysis, we observed increased Transforming growth factor-β (TGFβ) gene expression in CADASIL VSMCs. Adding TGFβ-neutralizing antibody restored the proliferation rate of CADASIL VSMCs. We assessed proliferation differences in the presence or absence of TGFβ-neutralizing antibody in ECs co-cultured with VSMCs. ECs co-cultured with CADASIL VSMCs exhibited a lower proliferation rate than those co-cultured with control VSMCs, and neutralization of TGFβ normalized the proliferation rate of ECs co-cultured with CADASIL VSMCs. We suggest that increased TGFβ expression in CADASIL VSMCs is involved in the reduced VSMC proliferation in CADASIL and may play a role in situ in altered proliferation of neighbouring cells in the vasculature. © 2018 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  11. Glutamate production from ammonia via glutamate dehydrogenase 2 activity supports cancer cell proliferation under glutamine depletion.

    Science.gov (United States)

    Takeuchi, Yukiko; Nakayama, Yasumune; Fukusaki, Eiichiro; Irino, Yasuhiro

    2018-01-01

    Cancer cells rapidly consume glutamine as a carbon and nitrogen source to support proliferation, but the cell number continues to increase exponentially after glutamine is nearly depleted from the medium. In contrast, cell proliferation rates are strongly depressed when cells are cultured in glutamine-free medium. How cancer cells survive in response to nutrient limitation and cellular stress remains poorly understood. In addition, rapid glutamine catabolism yields ammonia, which is a potentially toxic metabolite that is secreted into the extracellular space. Here, we show that ammonia can be utilized for glutamate production, leading to cell proliferation under glutamine-depleted conditions. This proliferation requires glutamate dehydrogenase 2, which synthesizes glutamate from ammonia and α-ketoglutarate and is expressed in MCF7 and T47D cells. Our findings provide insight into how cancer cells survive under glutamine deprivation conditions and thus contribute to elucidating the mechanisms of tumor growth. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Subcellular localization of p44/WDR77 determines proliferation and differentiation of prostate epithelial cells.

    Directory of Open Access Journals (Sweden)

    Shen Gao

    Full Text Available The molecular mechanism that controls the proliferation and differentiation of prostate epithelial cells is currently unknown. We previously identified a 44-kDa protein (p44/wdr77 as an androgen receptor-interacting protein that regulates a set of androgen receptor target genes in prostate epithelial cells and prostate cancer. In this study, we found that p44 localizes in the cytoplasm of prostate epithelial cells at the early stage of prostate development when cells are proliferating, and its nuclear translocation is associated with cellular and functional differentiation in adult prostate tissue. We further demonstrated that cytoplasmic p44 protein is essential for proliferation of prostate epithelial cells, whereas nuclear p44 is required for cell differentiation and prostate- specific protein secretion. These studies suggest a novel mechanism by which proliferation and differentiation of prostate epithelial cells are controlled by p44's location in the cell.

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

    Science.gov (United States)

    Taşcă, C; Stefăneanu, L; Vasilescu, C

    1986-01-01

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

  14. Ultrastructure of interstitial cells of Cajal in myenteric plexus of human colon

    DEFF Research Database (Denmark)

    Rumessen, Jüri Johs.; Vanderwinden, Jean-Marie; Rasmussen, Helle

    2009-01-01

    The role of the interstitial cells of Cajal (ICC) associated with the myenteric plexus (ICC-MP) as regulators of the motility of the colonic external muscle remains unclear. Ultrastructural studies of myenteric interstitial cells are lacking in human colon. We therefore characterized the distinct......The role of the interstitial cells of Cajal (ICC) associated with the myenteric plexus (ICC-MP) as regulators of the motility of the colonic external muscle remains unclear. Ultrastructural studies of myenteric interstitial cells are lacking in human colon. We therefore characterized...

  15. Postmortem ultrastructural analysis of a cornea transplanted with Descemet membrane endothelial keratoplasty.

    Science.gov (United States)

    Livny, Eitan; Parker, Jack S; van der Kaaij, Mariëlle; Haasdijk, Elize D; van der Wees, Jacqueline; Bruinsma, Marieke; Melles, Gerrit R J

    2014-08-01

    The aim of this study was to describe the ultrastructure of the host-donor interface in the eye of a recently deceased patient, who had undergone Descemet membrane endothelial keratoplasty. The eye was enucleated postmortem, and after standard decontamination, the corneoscleral button was excised, cut into 4 quadrants, and processed for light and transmission electron microscopy evaluation. Transmission electron microscopy revealed close attachment of the donor's Descemet membrane to the host's stroma and projection of stromal collagen fibers into the interfacial matrix, resembling a normal "virgin" corneal architecture. Ultrastructurally, an attached Descemet membrane endothelial keratoplasty graft closely resembles that of an unoperated, healthy eye with no appreciable adventitious or missing structures.

  16. Ultrastructural distinctions between adult pleomorphic rhabdomyosarcomas, pleomorphic liposarcomas, and pleomorphic malignant fibrous histiocytomas.

    Science.gov (United States)

    Weiss, L M; Warhol, M J

    1984-11-01

    The ultrastructural features of five pleomorphic rhabdomyosarcomas, five high-grade malignant fibrous histiocytomas, and five pleomorphic liposarcomas were studied. Electron microscopy was found to be consistently useful in distinguishing between these tumors. The rhabdomyosarcomas showed thick and thin filaments in complexes and consistently contained glycogen. The malignant fibrous histiocytomas had numerous lysosomes, often in cells with ruffled borders, and contained cells showing "myofibroblastic" differentiation. The liposarcomas showed abundant and coalescing lipid droplets, sparse stroma with condensation of amorphous granular materials surrounding plasma membranes, and prominent vascularity. Fourteen of the 15 tumors could be identified on the basis of ultrastructure; thus, electron microscopic examination is an important diagnostic tool for pleomorphic tumors.

  17. Ultra-Structural Changes of the Early Childhood Caries Starting Phases of Development

    Directory of Open Access Journals (Sweden)

    Kokoceva-Ivanovska Olga

    2014-03-01

    Full Text Available In the recent 20 years, besides dramatic reduction of caries in many countries where complex programme of prevention is carried out, prevalence of Early Childhood Caries (ECC has expressed continual growth trend. The aim of our research was to determine precisely ultra-structural changes in the enamel substance at the initial lesion of the ECC (white spot lesion, as initial change of great importance for its preventive aspect. Therefore, we directed our experiment to evaluate ultra-structural changes of the teeth enamel in primary teeth with circular caries in its opening stages of development: initial caries lesion and superficial form.

  18. Vulvar angiomyxoma, aggressive angiomyxoma, and angiomyofibroblastoma: an immunohistochemical and ultrastructural study.

    Science.gov (United States)

    Alameda, Francesc; Munné, Assumpció; Baró, Teresa; Iglesias, Mar; Condom, Enric; Lloreta-Trull, Josep; Serrano, Sergi

    2006-01-01

    To investigate the histogenetical unifying theory of a single, pluripotential primitive cell for vulvar angiomyxoma, aggresive angiomyxoma, and angiomyofibroblastoma, an optical, immunohistochemical and ultrastructural study of a superficial angiomyxoma, aggressive angiomyxoma, and angiomyofibroblastoma was performed. These three tumors showed immunohistochemical and ultrastructural overlapping features. The results of the study suggest that these three tumor entities probably arise on a common pluripotential primitive cell located around the vessels of connective tissue, which could show the capacity for modulating its penotype toward similar but distinct mature cell types.

  19. [Enzymatic and ultrastructural changes in isolated liver mitochondria from mice infected with several group A arboviruses].

    Science.gov (United States)

    Peshkova, E A; Bakhtin, E K

    1978-01-01

    Inoculation of white mice of varying body mass with pathologic strains of eastern and Venezuelan equine encephalomyelitis viruses and their attenuated variants (DNC-20/6 and No. 2621), promising as vaccine candidates, resulted in an increase of enzymatic activity and ultrastructural changes of isolated mitochondria from livers of the animals. The attenuated strains of the viruses were shown to induce temporary changes in both aspects of the study which became normal by the end of the study. There was a certain correlational dependence between the enzymatic activity and ultrastructural changes in isolated mitochondria associated with the use of energy in virus reproduction.

  20. Aldehyde dehydrogenases and cell proliferation.

    Science.gov (United States)

    Muzio, G; Maggiora, M; Paiuzzi, E; Oraldi, M; Canuto, R A

    2012-02-15

    deviation in hepatoma and lung cancer cell lines, as is the case in chemically induced hepatoma in rats. High ALDH3A1 expression and activity have been correlated with cell proliferation, resistance against aldehydes derived from lipid peroxidation, and resistance against drug toxicity, such as oxazaphosphorines. Indeed, cells with a high ALDH3A1 content are more resistant to the cytostatic and cytotoxic effects of lipidic aldehydes than are those with a low content. A reduction in cell proliferation can be observed when the enzyme is directly inhibited by the administration of synthetic specific inhibitors, antisense oligonucleotides, or siRNA or indirectly inhibited by the induction of peroxisome proliferator-activated receptor γ (PPARγ) with polyunsaturated fatty acids or PPARγ transfection. Conversely, cell proliferation is stimulated by the activation of ALDH3A1, whether by inhibiting PPARγ with a specific antagonist, antisense oligonucleotides, siRNA, or a medical device (i.e., composite polypropylene prosthesis for hernia repair) used to induce cell proliferation. To date, the mechanisms underlying the effects of ALDHs on cell proliferation are not yet fully clear. A likely hypothesis is that the regulatory effect is mediated by the catabolism of some endogenous substrates deriving from normal cell metabolism, such as 4-hydroxynonenal, which have the capacity to either stimulate or inhibit the expression of genes involved in regulating proliferation. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Cellular inhibitor of apoptosis protein 2 controls human colonic epithelial restitution, migration, and Rac1 activation

    DEFF Research Database (Denmark)

    Seidelin, Jakob Benedict; Larsen, Sylvester; Linnemann, Dorte

    2015-01-01

    Identification of pathways involved in wound healing is important for understanding the pathogenesis of various intestinal diseases. Cellular inhibitor of apoptosis protein 2 (cIAP2) regulates proliferation and migration in nonepithelial cells and is expressed in human colonocytes. The aim...

  2. The Role of Autophagy in Nanoparticles-Induced Toxicity and Its Related Cellular and Molecular Mechanisms.

    Science.gov (United States)

    Li, Yubin; Ju, Dianwen

    2018-01-01

    In the past decades, nanoparticles have been widely used in industry and pharmaceutical fields for drug delivery, anti-pathogen, and diagnostic imaging purposes because of their unique physicochemical characteristics such as special ultrastructure, dispersity, and effective cellular uptake properties. But the nanotoxicity has been raised over the extensive applications of nanoparticles. Researchers have elucidated series of mechanisms in nanoparticles-induced toxicity, including apoptosis, necrosis, oxidative stress, and autophagy. Among upon mechanisms, autophagy was recently recognized as an important cell death style in various nanoparticles-induced toxicity, but the role of autophagy and its related cellular and molecular mechanisms during nanoparticles-triggered toxicity were still confusing. In the chapter, we briefly introduced the general process of autophagy, summarized the different roles of autophagy in various nanoparticle-treated different in vitro/in vivo models, and deeply analyzed the physicochemical and biochemical (cellular and molecular) mechanisms of autophagy during nanoparticles-induced toxicity through listing and summarizing representative examples. Physicochemical mechanisms mainly include dispersity, size, charge, and surface chemistry; cellular mechanisms primarily focus on lysosome impairment, mitochondria dysfunction, mitophagy, endoplasmic reticulum stress and endoplasmic reticulum autophagy; while molecular mechanisms were mainly including autophagy related signaling pathways, hypoxia-inducible factor, and oxidative stress. This chapter highlighted the important role of autophagy as a critical mechanism in nanoparticles-induced toxicity, and the physicochemical and biochemical mechanisms of autophagy triggered by nanoparticles might be useful for establishing a guideline for the evaluation of nanotoxicology, designing and developing new biosafety nanoparticles in the future.

  3. Homeobox A7 stimulates breast cancer cell proliferation by up-regulating estrogen receptor-alpha

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada); Cheng, Jung-Chien [Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada); Huang, He-Feng, E-mail: huanghefg@hotmail.com [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Leung, Peter C.K., E-mail: peter.leung@ubc.ca [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada)

    2013-11-01

    Highlights: •HOXA7 regulates MCF7 cell proliferation. •HOXA7 up-regulates ERα expression. •HOXA7 mediates estrogen-induced MCF7 cell proliferation. -- Abstract: Breast cancer is the most common hormone-dependent malignancy in women. Homeobox (HOX) transcription factors regulate many cellular functions, including cell migration, proliferation and differentiation. The aberrant expression of HOX genes has been reported to be associated with human reproductive cancers. Estradiol (E2) and its nuclear receptors, estrogen receptor (ER)-alpha and ER-beta, are known to play critical roles in the regulation of breast cancer cell growth. However, an understanding of the potential relationship between HOXA7 and ER in breast cancer cells is limited. In this study, our results demonstrate that knockdown of HOXA7 in MCF7 cells significantly decreased cell proliferation and ERα expression. In addition, HOXA7 knockdown attenuated E2-induced cell proliferation as well as progesterone receptor (PR) expression. The stimulatory effects of E2 on cell proliferation and PR expression were abolished by co-treatment with ICI 182780, a selective ERα antagonist. In contrast, overexpression of HOXA7 significantly stimulated cell proliferation and ERα expression. Moreover, E2-induced cell proliferation, as well as PR expression, was enhanced by the overexpression of HOXA7. Neither knockdown nor overexpression of HOXA7 affected the ER-beta levels. Our results demonstrate a novel mechanistic role for HOXA7 in modulating breast cancer cell proliferation via regulation of ERα expression. This finding contributes to our understanding of the role HOXA7 plays in regulating the proliferation of ER-positive cancer cells.

  4. Homeobox A7 stimulates breast cancer cell proliferation by up-regulating estrogen receptor-alpha

    International Nuclear Information System (INIS)

    Zhang, Yu; Cheng, Jung-Chien; Huang, He-Feng; Leung, Peter C.K.

    2013-01-01

    Highlights: •HOXA7 regulates MCF7 cell proliferation. •HOXA7 up-regulates ERα expression. •HOXA7 mediates estrogen-induced MCF7 cell proliferation. -- Abstract: Breast cancer is the most common hormone-dependent malignancy in women. Homeobox (HOX) transcription factors regulate many cellular functions, including cell migration, proliferation and differentiation. The aberrant expression of HOX genes has been reported to be associated with human reproductive cancers. Estradiol (E2) and its nuclear receptors, estrogen receptor (ER)-alpha and ER-beta, are known to play critical roles in the regulation of breast cancer cell growth. However, an understanding of the potential relationship between HOXA7 and ER in breast cancer cells is limited. In this study, our results demonstrate that knockdown of HOXA7 in MCF7 cells significantly decreased cell proliferation and ERα expression. In addition, HOXA7 knockdown attenuated E2-induced cell proliferation as well as progesterone receptor (PR) expression. The stimulatory effects of E2 on cell proliferation and PR expression were abolished by co-treatment with ICI 182780, a selective ERα antagonist. In contrast, overexpression of HOXA7 significantly stimulated cell proliferation and ERα expression. Moreover, E2-induced cell proliferation, as well as PR expression, was enhanced by the overexpression of HOXA7. Neither knockdown nor overexpression of HOXA7 affected the ER-beta levels. Our results demonstrate a novel mechanistic role for HOXA7 in modulating breast cancer cell proliferation via regulation of ERα expression. This finding contributes to our understanding of the role HOXA7 plays in regulating the proliferation of ER-positive cancer cells

  5. Peroxisome proliferator-activated receptor gamma coactivator-1 alpha acts as a tumor suppressor in hepatocellular carcinoma.

    Science.gov (United States)

    Liu, Rui; Zhang, Haiyang; Zhang, Yan; Li, Shuang; Wang, Xinyi; Wang, Xia; Wang, Cheng; Liu, Bin; Zen, Ke; Zhang, Chen-Yu; Zhang, Chunni; Ba, Yi

    2017-04-01

    Peroxisome proliferator-activated receptor gamma coactivator-1 alpha plays a crucial role in regulating the biosynthesis of mitochondria, which is closely linked to the energy metabolism in various tumors. This study investigated the regulatory role of peroxisome proliferator-activated receptor gamma coactivator-1 alpha in the pathogenesis of hepatocellular carcinoma. In this study, the changes of peroxisome proliferator-activated receptor gamma coactivator-1 alpha messenger RNA levels between normal human liver and hepatocellular carcinoma tissue were examined by quantitative reverse transcription polymerase chain reaction. Knockdown of peroxisome proliferator-activated receptor gamma coactivator-1 alpha was conducted by RNA interference in the human liver cell line L02, while overexpression of peroxisome proliferator-activated receptor gamma coactivator-1 alpha was conducted by adenovirus encoding peroxisome proliferator-activated receptor gamma coactivator-1 alpha complementary DNA in the human hepatocarcinoma cell line HepG2. Cellular morphological changes were observed via optical and electron microscopy. Cellular apoptosis was determined by Hoechst 33258 staining. In addition, the expression levels of 21,400 genes in tissues and cells were detected by microarray. It was shown that peroxisome proliferator-activated receptor gamma coactivator-1 alpha expression was significantly downregulated in hepatocellular carcinoma compared with normal liver tissues. After knockdown of peroxisome proliferator-activated receptor gamma coactivator-1 alpha expression in L02 cells, cells reverted to immature and dedifferentiated morphology exhibiting cancerous tendency. Apoptosis occurred in the HepG2 cells after transfection by adenovirus encoding peroxisome proliferator-activated receptor gamma coactivator-1 alpha. Microarray analysis showed consistent results. The results suggest that peroxisome proliferator-activated receptor gamma coactivator-1 alpha acts as a tumor

  6. Leading research on artificial techniques controlling cellular function; Saibo zoshoku seigyo gijutsu no sendo kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    Advanced research and its applicability were surveyed to apply the advanced functional cells to industry. The basic target was set to develop, produce, control and utilize the functional cells, such as intelligent materials and self-regulation bioreactors. The regulation factors regarding apotosis, which is a process of cell suicide programmed within the cell itself of multicellular organisms, cell cycle and aging/ageless were investigated. Furthermore, the function of regulatory factors was investigated at the protein level. Injection of factors regulating cellular function and tissue engineering required for the regulation of cell proliferation were investigated. Tissue engineering is considered to be the intracellular regulation by gene transduction and the extracellular regulation by culture methods, such as coculture. Analysis methods for cell proliferation and function of living cells were investigated using the probes recognizing molecular structure. Novel biomaterials, artificial organ systems, cellular therapy and useful materials were investigated for utilizing the regulation techniques of cell proliferation. 425 refs., 85 figs., 9 tabs.

  7. Chronic murine myocarditis due to Trypanosoma cruzi: an ultrastructural study and immunochemical characterization of cardiac interstitial matrix

    Directory of Open Access Journals (Sweden)

    Sonia G. Andrade

    1986-03-01

    Full Text Available In an attempt to define the mouse-model for chronic Chagas' disease, a serological, histopathological and ultrastructural study as well as immunotyping of myocardium collagenic matrix were performed on Swiss mice, chronically infected with Trypanosoma cruzi strains: 21 SF and mambaí (Type II; PMN and Bolivia (Type III, spontaneously surviving after 154 to 468 days of infection. Haemagglutination and indirect immunofluorescence tests showed high titres of specific antibodies. The ultrastructural study disclosed the cellular constitution of the inflammatory infiltrate showing the predominance of monocytes, macrophages with intense phagocytic activity, fibroblasts, myofibroblasts and abundant collagen matrix suggesting the association of the inflammatory process with fibrogenesis in chronic chagasic cardiomyopathy. Artertolar and blood capillary alterations together with dissociation of cardiac cells from the capillary wall by edema and inflammation were related to ultrastructural lesions of myocardial cells. Rupture of parasitized cardiac myocells contribute to intensify the inflammatory process in focal areas. Collagen immunotyping showed the predominance of Types III and IV collagen. Collagen degradation and phagocytosis were present suggesting a reversibility of the fibrous process. The mouse model seems to be valuable in the study of the pathogenetic mechanisms in Chagas cardiomyopathy, providing that T. cruzi strains of low virulence and high pathogenecity are used.Utilizando o modelo experimental do camundongo, foi realizado um estudo sorológico, histopatológico e ultraestrutural bem como a imunotipagem do colágeno na matriz conjuntiva do miocárdio em camundongos suiços cronicamente infectados com as cepas 21 SF e Mambaí (Tipo II PMN e Bolívia (Tipo III por períodos de 154 a 468 dias. Os testes sorológicos e de imunofluorescência indireta mostraram altos títulos de anticorpos específicos. O estudo estrutural definiu melhor a

  8. Arabidopsis and Tobacco superman regulate hormone signalling and mediate cell proliferation and differentiation.

    Science.gov (United States)

    Nibau, Candida; Di Stilio, Verónica S; Wu, Hen-Ming; Cheung, Alice Y

    2011-01-01

    Arabidopsis thaliana superman (SUP) plays an important role during flower development by maintaining the boundary between stamens and carpels in the inner two whorls. It was proposed that SUP maintains this boundary by regulating cell proliferation in both whorls, as loss-of-function superman mutants produce more stamens at the expense of carpels. However, the cellular mechanism that underlies SUP function remains unknown. Here Arabidopsis or tobacco (Nicotiana tabacum) SUP was overexpressed in tobacco plants to substantiate SUP's role as a regulator of cell proliferation and boundary definition and provide evidence that its biological role may be mediated via hormonal changes. It was found that moderate levels of SUP stimulated cell growth and proliferation, whereas high levels were inhibitory. SUP stimulated auxin- and cytokinin-regulated processes, and cells overexpressing SUP displayed reduced hormone dependency for proliferation and regeneration into plants. SUP also induced proliferation of female traits in the second and third flower whorls and promoted differentiation of petaloid properties in sepals, further supporting a role for SUP as a boundary regulator. Moreover, cytokinin suppressed stamen development and promoted differentiation of carpeloid tissues, suggesting that SUP may regulate male and female development via its effect on cytokinin signalling. Taken together, these observations suggest a model whereby the effect of SUP on cell growth and proliferation involves the modulation of auxin- and cytokinin-regulated processes. Furthermore, differential SUP expression or different sensitivities of different cell types to SUP may determine whether SUP stimulates or suppresses their proliferation.

  9. Homeostatic proliferation fails to efficiently reactivate HIV-1 latently infected central memory CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Alberto Bosque

    2011-10-01

    Full Text Available Homeostatic proliferation ensures the longevity of central memory T-cells by inducing cell proliferation in the absence of cellular differentiation or activation. This process is governed mainly by IL-7. Central memory T-cells can also be stimulated via engagement of the T-cell receptor, leading to cell proliferation but also activation and differentiation. Using an in vitro model of HIV-1 latency, we have examined in detail the effects of homeostatic proliferation on latently infected central memory T cells. We have also used antigenic stimulation via anti-CD3/anti-CD28 antibodies and established a comparison with a homeostatic proliferation stimulus, to evaluate potential differences in how either treatment affects the dynamics of latent virus populations. First, we show that homeostatic proliferation, as induced by a combination of IL-2 plus IL-7, leads to partial reactivation of latent HIV-1 but is unable to reduce the size of the reservoir in vitro. Second, latently infected cells are able to homeostatically proliferate in the absence of viral reactivation or cell differentiation. These results indicate that IL-2 plus IL-7 may induce a detrimental effect by favoring the maintenance of the latent HIV-1 reservoir. On the other hand, antigenic stimulation efficiently reactivated latent HIV-1 in cultured central memory cells and led to depletion of the latently infected cells via virus-induced cell death.

  10. Effect of borax on immune cell proliferation and sister chromatid exchange in human chromosomes.

    Science.gov (United States)

    Pongsavee, Malinee

    2009-10-30

    Borax is used as a food additive. It becomes toxic when accumulated in the body. It causes vomiting, fatigue and renal failure. The heparinized blood samples from 40 healthy men were studied for the impact of borax toxicity on immune cell proliferation (lymphocyte proliferation) and sister chromatid exchange in human chromosomes. The MTT assay and Sister Chromatid Exchange (SCE) technic were used in this experiment with the borax concentrations of 0.1, 0.15, 0.2, 0.3 and 0.6 mg/ml. It showed that the immune cell proliferation (lymphocyte proliferation) was decreased when the concentrations of borax increased. The borax concentration of 0.6 mg/ml had the most effectiveness to the lymphocyte proliferation and had the highest cytotoxicity index (CI). The borax concentrations of 0.15, 0.2, 0.3 and 0.6 mg/ml significantly induced sister chromatid exchange in human chromosomes (P Borax had effects on immune cell proliferation (lymphocyte proliferation) and induced sister chromatid exchange in human chromosomes. Toxicity of borax may lead to cellular toxicity and genetic defect in human.

  11. Effect of borax on immune cell proliferation and sister chromatid exchange in human chromosomes

    Directory of Open Access Journals (Sweden)

    Pongsavee Malinee

    2009-10-01

    Full Text Available Abstract Background Borax is used as a food additive. It becomes toxic when accumulated in the body. It causes vomiting, fatigue and renal failure. Methods The heparinized blood samples from 40 healthy men were studied for the impact of borax toxicity on immune cell proliferation (lymphocyte proliferation and sister chromatid exchange in human chromosomes. The MTT assay and Sister Chromatid Exchange (SCE technic were used in this experiment with the borax concentrations of 0.1, 0.15, 0.2, 0.3 and 0.6 mg/ml. Results It showed that the immune cell proliferation (lymphocyte proliferation was decreased when the concentrations of borax increased. The borax concentration of 0.6 mg/ml had the most effectiveness to the lymphocyte proliferation and had the highest cytotoxicity index (CI. The borax concentrations of 0.15, 0.2, 0.3 and 0.6 mg/ml significantly induced sister chromatid exchange in human chromosomes (P Conclusion Borax had effects on immune cell proliferation (lymphocyte proliferation and induced sister chromatid exchange in human chromosomes. Toxicity of borax may lead to cellular toxicity and genetic defect in human.

  12. Imbalance between apoptosis and cell proliferation during early stages of mammary gland carcinogenesis in ACI rats

    International Nuclear Information System (INIS)

    Kutanzi, Kristy R.; Koturbash, Igor; Bronson, Roderick T.; Pogribny, Igor P.; Kovalchuk, Olga

    2010-01-01

    Estrogen and ionizing radiation are well-documented human breast carcinogens, yet the exact mechanisms of their deleterious effects on mammary gland remain to be discerned. Here we analyze the balance between cellular proliferation and apoptosis in the mammary glands of rats exposed to estrogen and X-ray radiation and the combined action of these carcinogenic agents. For the first time, we show that combined exposure to estrogen and radiation has a synergistic effect on cell proliferation in the mammary glands of ACI rats, as evidenced by a substantially greater magnitude of cell proliferation, especially after 12 and 18 weeks of treatment, when compared to mammary glands of rats exposed to estrogen or radiation alone. We also demonstrate that an imbalance between cell proliferation and apoptosis, rather than enhanced cell proliferation or apoptosis suppression alone, may be a driving force for carcinogenesis. Our studies further suggest that compromised functional activity of p53 may be one of the mechanisms responsible for the proliferation/apoptosis imbalance. In sum, the results of our study indicate that evaluation of the extent of cell proliferation and apoptosis before the onset of preneoplastic lesions may be a potential biomarker of breast cancer risk after exposure to breast carcinogens.

  13. COMPARATIVE SPERM ULTRASTRUCTURE OF BAIKALIAN ENDEMIC PROSOBRANCH GASTROPODS.

    Science.gov (United States)

    Ropstorf, PETER; Healy, JOHN M.; Riedel, FRANK; Sitnikova, TATIANA Y.

    2002-05-01

    Mature euspermatozoan ultrastructure is described for seven species of the rissooidean family Baicaliidae (endemic to Lake Baikal, Russia)-Liobaicalia stiedae, Teratobaikalia ciliata, T. macrostoma, Baicalia carinata, Pseudobaikalia pulla, Maackia bythiniopsis, M. variesculpta, and M. herderiana. For comparison with these species and previously investigated Rissooidea, two species of the Lake Baikal endemic genus Benedictia (B. cf. fragilis and B. baicalensis; Hydrobiidae: Benedictiinae of some authors, Benedictiidae of other authors) in addition to Lithoglyphus naticoides (Hydrobiidae: Lithoglyphinae) and Bythinella austriaca (Hydrobiidae: Bythinellinae) were also investigated. Paraspermatozoa were not observed in any of the species examined, supporting the view that these cells are probably absent in the Rissooidea. In general, the euspermatozoa of all species examined resemble those of many other caenogastropods (basally invaginated acrosomal vesicle, mid-piece with 7-13 helical mitochondria, an annulus, glycogen piece with nine peri-axonemal tracts of granules). However, the presence of a completely flattened acrosomal vesicle and a specialized peri-axonemal membranous sheath (a scroll-like arrangement of 4-6 double membranes) at the termination of the mid-piece, clearly indicates a close relationship between the Baicaliidae and other rissooidean families possessing these features (Bithyniidae, Hydrobiidae, Pyrgulidae, and Stenothyridae). Euspermatozoa of Benedictia, Lithoglyphus, Bythinella, and Pyrgula all have a solid nucleus, which exhibits a short, posterior invagination (housing the centriolar complex and proximal portion of the axoneme). Among the Rissooidea, this form of nucleus is known to occur in the Bithyniidae, Hydrobiidae, Truncatellidae, Pyrgulidae, Iravadiidae, Pomatiopsidae, and Stenothyridae. In contrast, the euspermatozoa of the Baicaliidae all have a long, tubular nucleus, housing not only the centriolar derivative, but also a substantial

  14. A computational framework for ultrastructural mapping of neural circuitry.

    Directory of Open Access Journals (Sweden)

    James R Anderson

    2009-03-01

    Full Text Available Circuitry mapping of metazoan neural systems is difficult because canonical neural regions (regions containing one or more copies of all components are large, regional borders are uncertain, neuronal diversity is high, and potential network topologies so numerous that only anatomical ground truth can resolve them. Complete mapping of a specific network requires synaptic resolution, canonical region coverage, and robust neuronal classification. Though transmission electron microscopy (TEM remains the optimal tool for network mapping, the process of building large serial section TEM (ssTEM image volumes is rendered difficult by the need to precisely mosaic distorted image tiles and register distorted mosaics. Moreover, most molecular neuronal class markers are poorly compatible with optimal TEM imaging. Our objective was to build a complete framework for ultrastructural circuitry mapping. This framework combines strong TEM-compliant small molecule profiling with automated image tile mosaicking, automated slice-to-slice image registration, and gigabyte-scale image browsing for volume annotation. Specifically we show how ultrathin molecular profiling datasets and their resultant classification maps can be embedded into ssTEM datasets and how scripted acquisition tools (SerialEM, mosaicking and registration (ir-tools, and large slice viewers (MosaicBuilder, Viking can be used to manage terabyte-scale volumes. These methods enable large-scale connectivity analyses of new and legacy data. In well-posed tasks (e.g., complete network mapping in retina, terabyte-scale image volumes that previously would require decades of assembly can now be completed in months. Perhaps more importantly, the fusion of molecular profiling, image acquisition by SerialEM, ir-tools volume assembly, and data viewers/annotators also allow ssTEM to be used as a prospective tool for discovery in nonneural systems and a practical screening methodology for neurogenetics. Finally

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

    Directory of Open Access Journals (Sweden)

    Nuran Ekici

    2009-03-01

    Full Text Available 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.O objetivo deste estudo é informar sobre a ultraestrutura de tubos de pólen de Mimulus aurantiacus in vivo coletados no "Botanical Garden" da Universidade da Califórnia em Berkeley. O material foi preparado de acordo com os métodos de microscopia eletrônica e examinado em microscópio eletrônico Zeiss. Quatro zonas dos tubos de pólen de Mimulus aurantiacus foram examinadas. ZONA APICAL: foram observados mitocôndrias, retículo endoplasmático liso; retículo endoplasmático rugoso, dictiossomos e vesículas secretoras. ZONA SUBAPICAL: esta área continha retículo endoplasmático rugoso em abundância e, ocasionalmente, algum retículo endoplasmático liso. Foram detectados polissomos, mitocôndrias, proplastídeos que contêm amido, pequenos vacúolos e

  16. Novel Materials for Cellular Nanosensors

    DEFF Research Database (Denmark)

    Sasso, Luigi

    The monitoring of cellular behavior is useful for the advancement of biomedical diagnostics, drug development and the understanding of a cell as the main unit of the human body. Micro- and nanotechnology allow for the creation of functional devices that enhance the study of cellular dynamics...... by providing platforms that offer biocompatible surfaces for the cell culturing in lab-on-chip devices integrated with optimized nanosensors with high specificities and sensitivities towards cellular analytes. In this project, novel materials were investigated with a focus on providing suitable surface...... modifications for electrochemical nanosensors for the detection of analytes released from cells. Two type of materials were investigated, each pertaining to the two different aspects of such devices: peptide nanostructures were studied for the creation of cellular sensing substrates that mimic in vivo surfaces...

  17. Systems biology of cellular rhythms.

    Science.gov (United States)

    Goldbeter, A; Gérard, C; Gonze, D; Leloup, J-C; Dupont, G

    2012-08-31

    Rhythms abound in biological systems, particularly at the cellular level where they originate from the feedback loops present in regulatory networks. Cellular rhythms can be investigated both by experimental and modeling approaches, and thus represent a prototypic field of research for systems biology. They have also become a major topic in synthetic biology. We review advances in the study of cellular rhythms of biochemical rather than electrical origin by considering a variety of oscillatory processes such as Ca++ oscillations, circadian rhythms, the segmentation clock, oscillations in p53 and NF-κB, synthetic oscillators, and the oscillatory dynamics of cyclin-dependent kinases driving the cell cycle. Finally we discuss the coupling between cellular rhythms and their robustness with respect to molecular noise.

  18. A Course in Cellular Bioengineering.

    Science.gov (United States)

    Lauffenburger, Douglas A.

    1989-01-01

    Gives an overview of a course in chemical engineering entitled "Cellular Bioengineering," dealing with how chemical engine