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Sample records for cellular proliferation ultrastructure

  1. Lycopene modulates cellular proliferation, glycolysis and hepatic ultrastructure during hepatocellular carcinoma

    PubMed Central

    Gupta, Prachi; Bhatia, Nisha; Bansal, Mohinder Pal; Koul, Ashwani

    2016-01-01

    AIM To investigate the effect of lycopene extracted from tomatoes (LycT) on ultrastructure, glycolytic enzymes, cell proliferation markers and hypoxia during N-Nitrosodiethylamine (NDEA)-induced hepatocarcinogenesis. METHODS Female BALB/c mice were randomly divided into four groups: The Control, NDEA (200 mg NDEA/kg b.w. given i.p.), LycT (5 mg/kg b.w. given orally on alternate days) and LycT + NDEA group. The mRNA and protein expression of various cell proliferation markers (PCNA, Cyclin D1, and p21) were assessed by reverse transcription-polymerase chain reaction and enzyme linked immunosorbent assay, respectively. The ultrastructure of hepatic tissue was analyzed using scanning and transmission electron microscopy. The enzymatic activity of glycolytic enzymes was estimated using standardized protocols, while glucose-6-phosphate dehydrogenase activity level was estimated using a kit obtained from Reckon Diagnostic P. Ltd. (India). RESULTS Uncontrolled proliferation in the liver of NDEA (P ≤ 0.001) mice was evident from the high expression of cell-proliferation associated genes (PCNA, Cyclin D1, and p21) when compared to control and LycT mice. In addition, enhanced activities of hexokinase, phosphoglucoisomerase, aldolase, glucose-6-phosphate dehydrogenase and hypoxia-inducible factor-1α were observed in NDEA mice as compared to control (P ≤ 0.001) and LycT (P ≤ 0.001) mice. The alterations in hepatic ultrastructure observed in the NDEA group correlated with the changes in the above parameters. LycT pre-treatment in NDEA-challenged mice ameliorated the investigated pathways disrupted by NDEA treatment. Moreover, hepatic electron micrographs from the LycT + NDEA group showed increased macrophages, apoptotic bodies and well-differentiated hepatocellular carcinoma (HCC) in comparison to undifferentiated HCC as observed in the NDEA treated group. CONCLUSION This study demonstrates that dietary supplementation with LycT has a multidimensional role in preventing

  2. Leukocytic Promotion of Prostate Cellular Proliferation

    PubMed Central

    McDowell, Kristy L.; Begley, Lesa A.; Mor-Vaknin, Nirit; Markovitz, David M.; Macoska, Jill A.

    2011-01-01

    BACKGROUND Histological evidence of pervasive inflammatory infiltrate has been noted in both benign prostatic hyperplasia/hypertrophy (BPH) and prostate cancer (PCa). Cytokines known to attract particular leukocyte subsets are secreted from prostatic stroma consequent to aging and also from malignant prostate epithelium. Therefore, we hypothesized that leukocytes associated with either acute or chronic inflammation attracted to the prostate consequent to aging or tumorigenesis may promote the abnormal cellular proliferation associated with BPH and PCa. METHODS An in vitro system designed to mimic the human prostatic microenvironment incorporating prostatic stroma (primary and immortalized prostate stromal fibroblasts), epithelium (N15C6, BPH-1, LNCaP, and PC3 cells), and inflammatory infiltrate (HL-60 cells, HH, and Molt-3 T-lymphocytes) was developed. Modified Boyden chamber assays were used to test the ability of prostate stromal and epithelial cells to attract leukocytes and to test the effect of leukocytes on prostate cellular proliferation. Antibody arrays were used to identify leukocyte-secreted cytokines mediating prostate cellular proliferation. RESULTS Leukocytic cells migrated towards both prostate stromal and epithelial cells. CD4+ T-lymphocytes promoted the proliferation of both transformed and non-transformed prostate epithelial cell lines tested, whereas CD8+ T-lymphocytes as well as dHL-60M macrophagic and dHL-60N neutrophilic cells selectively promoted the proliferation of PCa cells. CONCLUSIONS The results of these studies show that inflammatory cells can be attracted to the prostate tissue microenvironment and can selectively promote the proliferation of non-transformed or transformed prostate epithelial cells, and are consistent with differential role(s) for inflammatory infiltrate in the etiologies of benign and malignant proliferative disease in the prostate. PMID:19866464

  3. Cell Proliferation, Reactive Oxygen and Cellular Glutathione

    PubMed Central

    Day, Regina M.; Suzuki, Yuichiro J.

    2005-01-01

    A variety of cellular activities, including metabolism, growth, and death, are regulated and modulated by the redox status of the environment. A biphasic effect has been demonstrated on cellular proliferation with reactive oxygen species (ROS)—especially hydrogen peroxide and superoxide—in which low levels (usually submicromolar concentrations) induce growth but higher concentrations (usually >10–30 micromolar) induce apoptosis or necrosis. This phenomenon has been demonstrated for primary, immortalized and transformed cell types. However, the mechanism of the proliferative response to low levels of ROS is not well understood. Much of the work examining the signal transduction by ROS, including H2O2, has been performed using doses in the lethal range. Although use of higher ROS doses have allowed the identification of important signal transduction pathways, these pathways may be activated by cells only in association with ROS-induced apoptosis and necrosis, and may not utilize the same pathways activated by lower doses of ROS associated with increased cell growth. Recent data has shown that low levels of exogenous H2O2 up-regulate intracellular glutathione and activate the DNA binding activity toward antioxidant response element. The modulation of the cellular redox environment, through the regulation of cellular glutathione levels, may be a part of the hormetic effect shown by ROS on cell growth. PMID:18648617

  4. Cellular Ultrastructure and Crystal Development in Amorphophallus (Araceae)

    PubMed Central

    Prychid, Christina J.; Jabaily, Rachel Schmidt; Rudall, Paula J.

    2008-01-01

    Background and Aims Species of Araceae accumulate calcium oxalate in the form of characteristically grooved needle-shaped raphide crystals and multi-crystal druses. This study focuses on the distribution and development of raphides and druses during leaf growth in ten species of Amorphophallus (Araceae) in order to determine the crystal macropatterns and the underlying ultrastructural features associated with formation of the unusual raphide groove. Methods Transmission electron microscopy (TEM), scanning electron microscopy (SEM) and both bright-field and polarized-light microscopy were used to study a range of developmental stages. Key Results Raphide crystals are initiated very early in plant development. They are consistently present in most species and have a fairly uniform distribution within mature tissues. Individual raphides may be formed by calcium oxalate deposition within individual crystal chambers in the vacuole of an idioblast. Druse crystals form later in the true leaves, and are absent from some species. Distribution of druses within leaves is more variable. Druses initially develop at leaf tips and then increase basipetally as the leaf ages. Druse development may also be initiated in crystal chambers. Conclusions The unusual grooved raphides in Amorphophallus species probably result from an unusual crystal chamber morphology. There are multiple systems of transport and biomineralization of calcium into the vacuole of the idioblast. Differences between raphide and druse idioblasts indicate different levels of cellular regulation. The relatively early development of raphides provides a defensive function in soft, growing tissues, and restricts build-up of dangerously high levels of calcium in tissues that lack the ability to adequately regulate calcium. The later development of druses could be primarily for calcium sequestration. PMID:18285357

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

    PubMed Central

    Eroh, Guy D.; Clayton, Fred C.; Florell, Scott R.; Cassidy, Pamela B.; Chirife, Andrea; Marón, Carina F.; Valenzuela, Luciano O.; Campbell, Michael S.; Seger, Jon; Rowntree, Victoria J.; Leachman, Sancy A.

    2017-01-01

    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. PMID:28170433

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

    PubMed

    Eroh, Guy D; Clayton, Fred C; Florell, Scott R; Cassidy, Pamela B; Chirife, Andrea; Marón, Carina F; Valenzuela, Luciano O; Campbell, Michael S; Seger, Jon; Rowntree, Victoria J; Leachman, Sancy A

    2017-01-01

    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.

  7. Effect of Cadmium on Cellular Ultrastructure in Mouse Ovary.

    PubMed

    Wang, Ying; Wang, Xuejuan; Wang, Yanwu; Fan, Rong; Qiu, Chao; Zhong, Shan; Wei, Lei; Luo, Daji

    2015-01-01

    This study aimed at analyzing the cytotoxicity and pathological effects of cadmium on the ovary. Our studies revealed that cadmium was deposited in the mouse ovary after 8 d cadmium injection in vivo. Also, the increase in the rate of body weight was slowed, while the gonadosomatic index was reduced in the CdCl2 group, compared with the control group. Meanwhile, cadmium affected the maturation of follicles, the degradation of corpus luteum, the arrangement of follicles and corpus luteum, and increased the number of atresia follicles. Besides, under the electron microscope, chromatin margination, karopyknosis, swelling of mature cisternae of Golgi apparatus, mitochondrial cristae disappearance, and swelling of the rough endoplasmic reticulum can be observed in the CdCl2 group mice. Collectively, our findings elucidated the morphological mechanism that the exposure of cadmium changed the ultrastructure of cells in ovary tissues.

  8. Ultrastructural and cellular mechanisms in myocardial deconditioning in weightlessness

    NASA Technical Reports Server (NTRS)

    Philpott, Delbert E.; Kato, Katharine; Miquel, Jaime

    1992-01-01

    The cardiovascular deconditioning that has been shown to result from immobilization on earth and in the microgravity environment during spaceflight is considered. The major interests to future long-term spaceflight are the determination of the specific factors causing myocardial deconditioning, the irreversibility/reversibility of the changes, and preventative/treatment methods for this deconditioning process. The results of earlier animal studies designed to determine the effects of immobilization on myocardial function demonstrate that both ultrastructural and functional changes occur during test periods ranging from 14 days to 6 months. Based on such results and the need for a more precise understanding of the structural and biochemical mechanisms leading to these effects, an experiment was designed for use in future studies. The results of the Cosmos 1887 and 2044 flights as well as their comparison and analysis indicate that significant differences exist between simulated and actual spaceflight subjects. Spaceflight subjects demonstrate greater changes than tail-suspended subjects. More spaceflight studies will be necessary to gain a greater understanding of the basic mechanism behind myocardial deconditioning resulting from spaceflight and the most effective methods to be utilized in its prevention and treatment.

  9. 3-D Cellular Ultrastructure Can Be Resolved by X-ray Microscopy | Center for Cancer Research

    Cancer.gov

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

  10. Cellular proliferation after experimental glaucoma filtration surgery

    SciTech Connect

    Jampel, H.D.; McGuigan, L.J.; Dunkelberger, G.R.; L'Hernault, N.L.; Quigley, H.A.

    1988-01-01

    We used light microscopic autoradiography to determine the time course of cellular incorporation of tritiated thymidine (a correlate of cell division) following glaucoma filtration surgery in seven eyes of four cynomolgus monkeys with experimental glaucoma. Incorporation of tritiated thymidine was detected as early as 24 hours postoperatively. Peak incorporation occurred five days postoperatively and had returned to baseline levels by day 11. Cells incorporating tritiated thymidine included keratocytes, episcleral cells, corneal and capillary endothelial cells, and conjunctival and corneal epithelial cells. Transmission electron microscopy was correlated with the autoradiographic results to demonstrate that fibroblasts were dividing on the corneoscleral margin. These findings have potential clinical implications for the use of antiproliferative agents after filtration surgery.

  11. [Regulation of uterine cellular proliferation with estrogens and growth factors].

    PubMed

    Alvarez-Rodríguez, C; Baiza-Guzmán, L A

    1996-09-01

    In this paper the role of estrogen and growth factors in the uterine cellular proliferation is analyzed. The evidences indicate that the estradiol-stimulate cell division is associated with the induction of expression of a variety of growth factors from the all major uterine cell types (epithelia, stroma and myometrium). These growth factors amplify the estrogen proliferation signal in autocrine and/or paracrin fashion. The best-studied growth factors in the uterine response to estradiol are epidermal growth factor (EGF) and insulin-like growth factor (IGF-1). Uterine cell proliferation is a complex process that involves interactions of several growth factors, ovarian steroids hormones action and cell to cell signaling.

  12. Electron microscopy of high pressure frozen samples: bridging the gap between cellular ultrastructure and atomic resolution.

    PubMed

    Studer, Daniel; Humbel, Bruno M; Chiquet, Matthias

    2008-11-01

    Transmission electron microscopy has provided most of what is known about the ultrastructural organization of tissues, cells, and organelles. Due to tremendous advances in crystallography and magnetic resonance imaging, almost any protein can now be modeled at atomic resolution. To fully understand the workings of biological "nanomachines" it is necessary to obtain images of intact macromolecular assemblies in situ. Although the resolution power of electron microscopes is on the atomic scale, in biological samples artifacts introduced by aldehyde fixation, dehydration and staining, but also section thickness reduces it to some nanometers. Cryofixation by high pressure freezing circumvents many of the artifacts since it allows vitrifying biological samples of about 200 mum in thickness and immobilizes complex macromolecular assemblies in their native state in situ. To exploit the perfect structural preservation of frozen hydrated sections, sophisticated instruments are needed, e.g., high voltage electron microscopes equipped with precise goniometers that work at low temperature and digital cameras of high sensitivity and pixel number. With them, it is possible to generate high resolution tomograms, i.e., 3D views of subcellular structures. This review describes theory and applications of the high pressure cryofixation methodology and compares its results with those of conventional procedures. Moreover, recent findings will be discussed showing that molecular models of proteins can be fitted into depicted organellar ultrastructure of images of frozen hydrated sections. High pressure freezing of tissue is the base which may lead to precise models of macromolecular assemblies in situ, and thus to a better understanding of the function of complex cellular structures.

  13. Inositol hexaphosphate (IP6) inhibits cellular proliferation in melanoma.

    PubMed

    Rizvi, Irfan; Riggs, Dale R; Jackson, Barbara J; Ng, Alex; Cunningham, Cynthia; McFadden, David W

    2006-06-01

    Inositol Hexaphosphate (IP6) is a naturally occurring polyphosphorylated carbohydrate found in food sources high in fiber content. We have previously reported IP6 to have significant inhibitory effects against pancreatic cancer in vitro. We hypothesized that the IP6 would significantly inhibit cell growth of cutaneous melanoma in vitro. The melanoma line HTB68 was cultured using standard techniques and treated with IP6 at doses ranging from 0.2 to 1.0 mM/well. Cell viability was measured by MTT at 72 h. VEGF production was measured in the cell supernatants by ELISA. Apoptosis was evaluated by Annexin V-FITC and results calculated using FACS analysis. Statistical analysis was performed by ANOVA. Significant reductions (P < 0.001) in cellular proliferation were observed with IP6. Overall, IP6 exhibited a mean inhibition of cell growth of 52.1 +/- 11.5% (range, 1.6-83.0%) at 72 h of incubation. VEGF production was significantly reduced (P < 0.001) by the addition of IP6 (7.5 pg/ml) compared to control (40.9 pg/ml). IP6 significantly increased (P = 0.029) late apoptosis from 5.3 to 7.0% gated events. No changes in necrosis or early apoptosis were observed. Adjuvant treatment of melanoma continues to challenge clinicians and patients. Our findings that IP6 significantly decreased cellular growth, VEGF production and increased late apoptosis in melanoma suggest its potential therapeutic value. Further in vivo studies are planned to evaluate safety and clinical utility of this agent.

  14. Local cellular neighbourhood controls proliferation in cell competition.

    PubMed

    Bove, Anna; Gradeci, Daniel; Fujita, Yasuyuki; Banerjee, Shiladitya; Charras, Guillaume; Lowe, Alan R

    2017-09-20

    Cell competition is a quality control mechanism through which tissues eliminate unfit cells. Cell competition can result from short-range biochemical inductions or long-range mechanical cues. However, little is known about how cell-scale interactions give rise to population shifts in tissues, due to the lack of experimental and computational tools to efficiently characterise interactions at the single-cell level. Here, we address these challenges by combining long-term automated microscopy with deep learning image analysis to decipher how single-cell behaviour determines tissue make-up during competition. Using our high-throughput analysis pipeline, we show that competitive interactions between MDCK wild-type cells and cells depleted of the polarity protein scribble are governed by differential sensitivity to local density and the cell-type of each cell's neighbours. We find that local density has a dramatic effect on the rate of division and apoptosis under competitive conditions. Strikingly, our analysis reveals that proliferation of the winner cells is upregulated in neighbourhoods mostly populated by loser cells. These data suggest that tissue-scale population shifts are strongly affected by cellular-scale tissue organisation. We present a quantitative mathematical model that demonstrates the effect of neighbour cell-type dependence of apoptosis and division in determining the fitness of competing cell lines. © 2017 by The American Society for Cell Biology.

  15. Angiotensin II causes cellular proliferation in infantile haemangioma via angiotensin II receptor 2 activation.

    PubMed

    Itinteang, Tinte; Marsh, Reginald; Davis, Paul Frank; Tan, Swee Thong

    2015-05-01

    To investigate the effect of the angiotensin peptides and their agonists and antagonists on cellular proliferation in proliferating infantile haemangioma (IH) in vitro explants. Proliferating IH samples from six patients were cultured in vitro in the presence of angiotensin I (ATI) alone, or AT1 and the ACE inhibitor, ramipril, or ATII alone, or ATII with the ATII receptor 1 (ATIIR1) blocker, losartan, or ATII with the ATIIR2 blocker, PD123319, or the ATIIR2 agonist, CGP42112. After 6 days in culture, the IH tissue pieces were harvested, formalin-fixed and paraffin-embedded. The effect of each treatment type on cellular proliferation was evaluated by immunohistochemical staining of these tissue pieces using the proliferation marker, Ki67. There was a significant increase in cellular proliferation in the ATI and ATII treated IH tissues compared with control samples. Their effect on cellular proliferation was reduced by adding ramipril and PD123319, respectively. CGP42112, but not losartan, significantly increased cellular proliferation. Our findings suggest a key regulatory role of ATI and ATII in promoting cellular proliferation in IH, and establish a role for ACE and ATIIR2 in the proliferation of this tumour. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

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

    PubMed Central

    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.

  17. Excessive Cellular Proliferation Negatively Impacts Reprogramming Efficiency of Human Fibroblasts

    PubMed Central

    Gupta, Manoj K.; Teo, Adrian Kee Keong; Rao, Tata Nageswara; Bhatt, Shweta; Kleinridders, Andre; Shirakawa, Jun; Takatani, Tomozumi; Hu, Jiang; De Jesus, Dario F.; Windmueller, Rebecca; Wagers, Amy J.

    2015-01-01

    The impact of somatic cell proliferation rate on induction of pluripotent stem cells remains controversial. Herein, we report that rapid proliferation of human somatic fibroblasts is detrimental to reprogramming efficiency when reprogrammed using a lentiviral vector expressing OCT4, SOX2, KLF4, and cMYC in insulin-rich defined medium. Human fibroblasts grown in this medium showed higher proliferation, enhanced expression of insulin signaling and cell cycle genes, and a switch from glycolytic to oxidative phosphorylation metabolism, but they displayed poor reprogramming efficiency compared with cells grown in normal medium. Thus, in contrast to previous studies, our work reveals an inverse correlation between the proliferation rate of somatic cells and reprogramming efficiency, and also suggests that upregulation of proteins in the growth factor signaling pathway limits the ability to induce pluripotency in human somatic fibroblasts. Significance The efficiency with which human cells can be reprogrammed is of interest to stem cell biology. In this study, human fibroblasts cultured in media containing different concentrations of growth factors such as insulin and insulin-like growth factor-1 exhibited variable abilities to proliferate, with consequences on pluripotency. This occurred in part because of changes in the expression of proteins involved in the growth factor signaling pathway, glycolysis, and oxidative phosphorylation. These findings have implications for efficient reprogramming of human cells. PMID:26253715

  18. hTR RNA component as a marker of cellular proliferation in oral lichen planus.

    PubMed

    Flatharta, Cathal O; Flint, Stephen; Toner, Mary; Mabruk, Mohamed

    2008-01-01

    Previously, we have shown that the telomerase RNA component hTR is highly expressed in the epithelium of non-dysplastic Oral Lichen Planus (OLP) lesions (11). We concluded that it is possible that this high expression might be related to the increased cellular proliferation seen in OLP rather than being an indicator of potential malignant transformation. In the present study, and in order to confirm our finding in the previous study that hTR might be a marker for cellular proliferation in OLP, we analysed OLP biopsies known to be positive for RNA component of Telomerase (hTR) for the expression of Ki-67 as a marker for cellular proliferation. Fourteen OLP tissue biopsies known to be positive for telomerase RNA component hTR, were investigated using an immunohistochemical approach to determine the rate of cellular proliferation in OLP, looking at the expression of Ki-67 protein as a marker for cellular proliferation. A statistically significant increase was found between Ki-67 expression in OLP in comparison to normal control buccal mucosa samples. The expression of hTR component in OLP might thus be a marker for cellular proliferation.

  19. ETO2 coordinates cellular proliferation and differentiation during erythropoiesis

    PubMed Central

    Goardon, Nicolas; Lambert, Julie A; Rodriguez, Patrick; Nissaire, Philippe; Herblot, Sabine; Thibault, Pierre; Dumenil, Dominique; Strouboulis, John; Romeo, Paul-Henri; Hoang, Trang

    2006-01-01

    The passage from proliferation to terminal differentiation is critical for normal development and is often perturbed in malignancies. To define the molecular mechanisms that govern this process during erythropoiesis, we have used tagging/proteomics approaches and characterized protein complexes nucleated by TAL-1/SCL, a basic helix–loop–helix transcription factor that specifies the erythrocytic lineage. In addition to known TAL-1 partners, GATA-1, E2A, HEB, LMO2 and Ldb1, we identify the ETO2 repressor as a novel component recruited to TAL-1 complexes through interaction with E2A/HEB. Ectopic expression and siRNA knockdown experiments in hematopoietic progenitor cells show that ETO2 actively represses erythroid TAL-1 target genes and governs the expansion of erythroid progenitors. At the onset of erythroid differentiation, a change in the stoichiometry of ETO2 within the TAL-1 complex activates the expression of known erythroid-specific TAL-1 target genes and of Gfi-1b and p21Cip, encoding two essential regulators of erythroid cell proliferation. These results suggest that the dynamics of ETO2 recruitment within nuclear complexes couple cell proliferation to cell differentiation and determine the onset of terminal erythroid maturation. PMID:16407974

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

    PubMed

    Domura, Ryota; Sasaki, Rie; Ishikawa, Yuma; Okamoto, Masami

    2017-06-06

    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.

  1. Cadmium suppresses the proliferation of piglet Sertoli cells and causes their DNA damage, cell apoptosis and aberrant ultrastructure

    PubMed Central

    2010-01-01

    Objective Very little information is known about the toxic effects of cadmium on somatic cells in mammalian testis. The objective of this study is to explore the toxicity of cadmium on piglet Sertoli cells. Methods Sertoli cells were isolated from piglet testes using a two-step enzyme digestion and followed by differential plating. Piglet Sertoli cells were identified by oil red O staining and Fas ligand (FasL) expression as assayed by immunocytochemistry and expression of transferrin and androgen binding protein by RT-PCR. Sertoli cells were cultured in DMEM/F12 supplemented with 10% fetal calf serum in the absence or presence of various concentrations of cadmium chloride, or treatment with p38 MAPK inhibitor SB202190 and with cadmium chloride exposure. Apoptotic cells in seminiferous tubules of piglets were also performed using TUNEL assay in vivo. Results Cadmium chloride inhibited the proliferation of Piglet Sertoli cells as shown by MTT assay, and it increased malondialdehyde (MDA) but reduced superoxide dismutase (SOD) and Glutathione peroxidase (GSH-Px) activity. Inhibitor SB202190 alleviated the proliferation inhibition of cadmium on piglet Sertoli cells. Comet assay revealed that cadmium chloride caused DNA damage of Piglet Sertoli cells and resulted in cell apoptosis as assayed by flow cytometry. The in vivo study confirmed that cadmium induced cell apoptosis in seminiferous tubules of piglets. Transmission electronic microscopy showed abnormal and apoptotic ultrastructure in Piglet Sertoli cells treated with cadmium chloride compared to the control. Conclusion cadmium has obvious adverse effects on the proliferation of piglet Sertoli cells and causes their DNA damage, cell apoptosis, and aberrant morphology. This study thus offers novel insights into the toxicology of cadmium on male reproduction. PMID:20712887

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

    PubMed

    Elmehdawi, Fatima; Wheway, Gabrielle; Szymanska, Katarzyna; Adams, Matthew; High, Alec S; Johnson, Colin A; Robinson, Philip A

    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.

  3. Interference microscopy delineates cellular proliferations on flat mounted internal limiting membrane specimens.

    PubMed

    Gandorfer, A; Scheler, R; Schumann, R; Haritoglou, C; Kampik, A

    2009-01-01

    To demonstrate that interference microscopy of flat mounted internal limiting membrane specimens clearly delineates cellular proliferations at the vitreomacular interface. ILM specimens harvested during vitrectomy were fixed in glutaraldehyde 0.05% and paraformaldehyde 2% for 24 h (pH 7.4). In addition to interference microscopy, immunocytochemistry using antibodies against glial fibrillar acidic protein (GFAP) and neurofilament (NF) was performed. After washing in phosphate-buffered saline 0.1 M, the specimens were flat-mounted on glass slides without sectioning, embedding or any other technique of conventional light microscopy. A cover slide and 4',6-diamidino-2-phenylindole (DAPI) medium were added to stain the cell nuclei. Interference microscopy clearly delineates cellular proliferations at the ILM. DAPI stained the cell nuclei. Areas of cellular proliferation can be easily distinguished from ILM areas without cells. Immunocytochemistry can be performed without changing the protocols used in conventional microscopy. Interference microscopy of flat mounted ILM specimens gives new insights into the distribution of cellular proliferations at the vitreomacular interface and allows for determination of the cell density at the ILM. Given that the entire ILM peeled is seen en face, the techniques described offer a more reliable method to investigate the vitreoretinal interface in terms of cellular distribution compared with conventional microscopy.

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

    PubMed

    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.

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

    PubMed Central

    Elkhatib, Walid F.

    2016-01-01

    The purpose of this study was to: (i) evaluate the antibacterial activities of three Egyptian honeys collected from different floral sources (namely, citrus, clover, and marjoram) against Escherichia coli; (ii) investigate the effects of these honeys on bacterial ultrastructure; and (iii) assess the anti-virulence potential of these honeys, by examining their impacts on the expression of eight selected genes (involved in biofilm formation, quorum sensing, and stress survival) in the test organism. The minimum inhibitory concentration (MIC) of the honey samples against E. coli ATCC 8739 were assessed by the broth microdilution assay in the presence and absence of catalase enzyme. Impacts of the honeys on the cellular ultrastructure and the expression profiles of the selected genes of E. coli were examined using transmission electron microscopy (TEM) and quantitative real-time polymerase chain reaction (qPCR) analysis, respectively. The susceptibility tests showed promising antibacterial activities of all the tested honeys against E. coli. This was supported by the TEM observations, which revealed “ghost” cells lacking DNA, in addition to cells with increased vacuoles, and/or with irregular shrunken cytoplasm. Among the tested honeys, marjoram exhibited the highest total antibacterial activity and the highest levels of peroxide-dependent activity. The qPCR analysis showed that all honey-treated cells share a similar overall pattern of gene expression, with a trend toward reduced expression of the virulence genes of interest. Our results indicate that some varieties of the Egyptian honey have the potential to be effective inhibitor and virulence modulator of E. coli via multiple molecular targets. PMID:26954570

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

    PubMed

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

    2014-01-01

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

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

    PubMed Central

    2009-01-01

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

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

    SciTech Connect

    Elmehdawi, Fatima; Wheway, Gabrielle; Szymanska, Katarzyna; Adams, Matthew; High, Alec S.; Johnson, Colin A.; Robinson, Philip A.

    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.

  9. Ultrastructural Analysis of the Human Lens Fiber Cell Remodeling Zone and the Initiation of Cellular Compaction

    PubMed Central

    Costello, M. Joseph; Mohamed, Ashik; Gilliland, Kurt O.; Fowler, W. Craig; Johnsen, Sönke

    2013-01-01

    The purpose is to determine the nature of the cellular rearrangements occurring through the remodeling zone (RZ) in human donor lenses, identified previously by confocal microscopy to be about 100 µm from the capsule. Human donor lenses were fixed with 10% formalin followed by 4% paraformaldehyde prior to processing for transmission electron microscopy. Of 27 fixed lenses, ages 22, 55 and 92 years were examined in detail. Overview electron micrographs confirmed the loss of cellular organization present in the outer cortex (80 µm thick) as the cells transitioned into the RZ. The transition occurred within a few cell layers and fiber cells in the RZ completely lost their classical hexagonal cross-sectional appearance. Cell interfaces became unusually interdigitated and irregular even though the radial cell columns were retained. Gap junctions appeared to be unaffected. After the RZ (40 µm thick), the cells were still irregular but more recognizable as fiber cells with typical interdigitations and the appearance of undulating membranes. Cell thickness was irregular after the RZ with some cells compacted, while others were not, up to the zone of full compaction in the adult nucleus. Similar dramatic cellular changes were observed within the RZ for each lens regardless of age. Because the cytoskeleton controls cell shape, dramatic cellular rearrangements that occur in the RZ most likely are due to alterations in the associations of crystallins to the lens-specific cytoskeletal beaded intermediate filaments. It is also likely that cytoskeletal attachments to membranes are altered to allow undulating membranes to develop. PMID:24183661

  10. Trypanosoma cruzi induces cellular proliferation in the trophoblastic cell line BeWo.

    PubMed

    Droguett, Daniel; Carrillo, Ileana; Castillo, Christian; Gómez, Fresia; Negrete, Miguel; Liempi, Ana; Muñoz, Lorena; Galanti, Norbel; Maya, Juan Diego; Kemmerling, Ulrike

    2017-02-01

    Congenital transmission of Trypanosoma cruzi (T. cruzi) is partially responsible for the progressive globalization of Chagas disease. During congenital transmission the parasite must cross the placental barrier where the trophoblast, a continuous renewing epithelium, is the first tissue in contact with the parasite. The trophoblast turnover implies cellular proliferation, differentiation and apoptotic cell death. The epithelial turnover is considered part of innate immunity. We previously demonstrated that T. cruzi induces cellular differentiation and apoptosis in this tissue. Here we demonstrate that T. cruzi induces cellular proliferation in a trophoblastic cell line. We analyzed the cellular proliferation in BeWo cells by determining DNA synthesis by BrdU incorporation assays, mitotic index, cell cycle analysis by flow cytometry, as well as quantification of nucleolus organizer regions by histochemistry and expression of the proliferation markers PCNA and Ki67 by Western blotting and/or immunofluorescence. Additionally, we determined the ERK1/2 MAPK pathway activation by the parasite by Western blotting.

  11. Variations in the cellular proliferation of prolactin cells from late pregnancy to lactation in rats.

    PubMed

    Carretero, José; Rubio, Manuel; Blanco, Enrique; Burks, Deborah J; Torres, José L; Hernández, Elena; Bodego, Pilar; Riesco, José M; Juanes, Juan A; Vázquez, Ricardo

    2003-04-01

    Lactation is a physiological process associated with hyperactivity of hypophyseal prolactin-producing cells. It is known that the percentage of these cells is increased during lactation, although there are discrepancies in the reports regarding the mechanisms responsible for increasing the number of prolactin cells. In order to analyse whether this increase is a result of previous proliferation, variations in the proliferation rate of prolactin-positive cells were determined from late pregnancy to lactation in adult female rats by means of observation of the immunohistochemical expression of PCNA as a marker of cellular proliferation. During late pregnancy, a very significant increase in the percentage of proliferating prolactin cells was observed in comparison to non-pregnant females in the proestrus phase (p < 0.01). Although the percentage of prolactin-positive cells after one week of lactation was higher than in non-lactating or in pregnant females (p < 0.01), the proliferation rate was lower than in the other groups studied. In sum, our results suggest that late pregnancy constitutes a preliminary proliferative phase preparatory to the ensuing lactation phase and that endocrine changes in late pregnancy involve the cellular proliferation of hypophyseal prolactin cells in order to prepare the gland for later demands and to prevent proliferative changes from occurring during lactation.

  12. Tetraspanin CD9 modulates human lymphoma cellular proliferation via histone deacetylase activity

    SciTech Connect

    Herr, Michael J.; Longhurst, Celia M.; Baker, Benjamin; Homayouni, Ramin; Speich, Henry E.; Kotha, Jayaprakash; Jennings, Lisa K.

    2014-05-16

    Highlights: • CD9 is differentially expressed in human Burkitt’s lymphoma cells. • We found that CD9 expression promotes these cells proliferation. • CD9 expression also increases HDAC activity. • HDAC inhibition decreased both cell proliferation and importantly CD9 expression. • CD9 may dictate HDAC efficacy and play a role in HDAC regulation. - Abstract: Non-Hodgkin Lymphoma (NHL) is a type of hematological malignancy that affects two percent of the overall population in the United States. Tetraspanin CD9 is a cell surface protein that has been thoroughly demonstrated to be a molecular facilitator of cellular phenotype. CD9 expression varies in two human lymphoma cell lines, Raji and BJAB. In this report, we investigated the functional relationship between CD9 and cell proliferation regulated by histone deacetylase (HDAC) activity in these two cell lines. Introduction of CD9 expression in Raji cells resulted in significantly increased cell proliferation and HDAC activity compared to Mock transfected Raji cells. The increase in CD9–Raji cell proliferation was significantly inhibited by HDAC inhibitor (HDACi) treatment. Pretreatment of BJAB cells with HDAC inhibitors resulted in a significant decrease in endogenous CD9 mRNA and cell surface expression. BJAB cells also displayed decreased cell proliferation after HDACi treatment. These results suggest a significant relationship between CD9 expression and cell proliferation in human lymphoma cells that may be modulated by HDAC activity.

  13. The antiproliferative effects of agmatine correlate with the rate of cellular proliferation.

    PubMed

    Isome, Masato; Lortie, Mark J; Murakami, Yasuko; Parisi, Eva; Matsufuji, Senya; Satriano, Joseph

    2007-08-01

    Polyamines are small cationic molecules required for cellular proliferation. Agmatine is a biogenic amine unique in its capacity to arrest proliferation in cell lines by depleting intracellular polyamine levels. We previously demonstrated that agmatine enters mammalian cells via the polyamine transport system. As polyamine transport is positively correlated with the rate of cellular proliferation, the current study examines the antiproliferative effects of agmatine on cells with varying proliferative kinetics. Herein, we evaluate agmatine transport, intracellular accumulation, and its effects on antizyme expression and cellular proliferation in nontransformed cell lines and their transformed variants. H-ras- and Src-transformed murine NIH/3T3 cells (Ras/3T3 and Src/3T3, respectively) that were exposed to exogenous agmatine exhibit increased uptake and intracellular accumulation relative to the parental NIH/3T3 cell line. Similar increases were obtained for human primary foreskin fibroblasts relative to a human fibrosarcoma cell line, HT1080. Agmatine increases expression of antizyme, a protein that inhibits polyamine biosynthesis and transport. Ras/3T3 and Src/3T3 cells demonstrated augmented increases in antizyme protein expression relative to NIH/3T3 in response to agmatine. All transformed cell lines were significantly more sensitive to the antiproliferative effects of agmatine than nontransformed lines. These effects were attenuated in the presence of exogenous polyamines or inhibitors of polyamine transport. In conclusion, the antiproliferative effects of agmatine preferentially target transformed cell lines due to the increased agmatine uptake exhibited by cells with short cycling times.

  14. Induction of sister chromatid exchanges and inhibition of cellular proliferation in vitro. I. Caffeine

    SciTech Connect

    Guglielmi, G.E.; Vogt, T.F.; Tice, R.R.

    1982-01-01

    While many agents have been examined for their ability to induce SCE's, complete dose-response information has often been lacking. We have reexamined the ability of one such compound - caffeine - to induce SCEs and also to inhibit cellular proliferation in human peripheral lymphocytes in vitro. An acute exposure to caffeine prior to the DNA synthetic period did not affect either SCE frequency or the rate of cellular proliferation. Chronic exposure to caffeine throughout the culture period lead to both a dose-dependent increase in SCEs (SCE/sub d/ or doubling dose = 2.4 mM; SCE/sub 10/ or the dose capable of inducing 10 SCE = 1.4 mM) and a dose-dependent inhibition of cellular proliferation (IC/sub 50/ or the 50% inhibition concentration = 2.6 mM). The relative proportion of first generation metaphase cells, an assessment of proliferative inhibiton, increased linearly with increasing caffeine concentrations. However, SCE frequency increased nonlinearly over the same range of caffeine concentrations. Examination of the ratio of nonsymmetrical to symmetrical SCEs in third generation metaphase cells indicated that caffeine induced SCEs in equal frequency in each of three successive generations. The dependency of SCE induction and cellular proliferative inhibition on caffeine's presence during the DNA synthetic period suggests that caffeine may act as an antimetabolite in normal human cells.

  15. Proliferating activity in differential diagnosis of benign phyllodes tumor and cellular fibroadenomas: is it helpful?

    PubMed

    Kaya, R; Pestereli, H E; Erdogan, G; Gülkesen, K H; Karaveli, S

    2001-01-01

    Benign phyllodes tumors and fibroadenomas are two types of fibroepithelial tumors of breast that are usually difficult to differentiate. The purpose of this study is to evaluate the proliferative activity of these tumors and to find out if it helps in differential diagnosis. Thirty-one benign phyllodes tumors and twelve cellular fibroadenomas were retrieved from the archives of Pathology Department of Akdeniz University, School of Medicine. Proliferating activity of epithelial and stromal cells were evaluated by using labeling index (LI) of proliferating cell nuclear antigen (PCNA) and Ki-67 antigen by immunohistochemistry. The results were compared with other clinicopathologic findings. There was not any significant difference between the proliferating activity of phyllodes tumor and cellular fibroadenomas. Mean LI of PCNA was 28.01 (+/-22.85) in stromal cells and 56.57 (+/-30.98) in epithelial cells of phyllodes tumor where it was 28.92 (+/-24.02) and 62.53 (+/-32.56) in fibroadenomas. Ki-67 indices were 0.05 (+/-0.19) in stromal cells, 2.65 (+/-12.53) in epithelial cells of phyllodes tumors and 0.0 (+/-0) in stromal cells, 0.43 (+/-0.63) in epithelial cells of fibroadenomas. There was no correlation between the diameter of tumors and proliferating activity in both groups. Proliferating activity, determined by immunohistochemistry with PCNA and Ki-67 antibodies did not reveal significant difference between phyllodes tumor and fibroadenoma.

  16. A regional ultrastructural analysis of the cellular and synaptic architecture in the chinchilla cristae ampullares

    NASA Technical Reports Server (NTRS)

    Lysakowski, A.; Goldberg, J. M.

    1997-01-01

    The chinchilla crista ampullaris was studied in 10 samples, each containing 32 consecutive ultrathin sections of the entire neuroepithelium. Dissector methods were used to estimate the incidence of various synaptic features, and results were confirmed in completely reconstructed hair cells. There are large regional variations in cellular and synaptic architecture. Type I and type II hair cells are shorter, broader, and less densely packed in the central zone than in the intermediate and peripheral zones. Complex calyx endings are most common centrally. On average, there are 15-20 ribbon synapses and 25-30 calyceal invaginations in each type I hair cell. Synapses and invaginations are most numerous centrally. Central type II hair cells receive considerably fewer afferent boutons than do peripheral type II hair cells, but have similar numbers of ribbon synapses. The numbers are similar because central type II hair cells make more synapses with the outer faces of calyx endings and with individual afferent boutons. Most afferent boutons get one ribbon synapse. Boutons without ribbon synapses were only found peripherally, and boutons getting multiple synapses were most frequent centrally. Throughout the neuroepithelium, there is an average of three to four efferent boutons on each type II hair cell and calyx ending. Reciprocal synapses are rare. Most synaptic ribbons in type I hair cells are spherules; those in type II hair cells can be spherical or elongated and are particularly heterogeneous centrally. Consistent with the proposal that the crista is concentrically organized, the intermediate and peripheral zones are each similar in their cellular and synaptic architecture near the base and near the planum. An especially differentiated subzone may exist in the middle of the central zone.

  17. A regional ultrastructural analysis of the cellular and synaptic architecture in the chinchilla cristae ampullares

    NASA Technical Reports Server (NTRS)

    Lysakowski, A.; Goldberg, J. M.

    1997-01-01

    The chinchilla crista ampullaris was studied in 10 samples, each containing 32 consecutive ultrathin sections of the entire neuroepithelium. Dissector methods were used to estimate the incidence of various synaptic features, and results were confirmed in completely reconstructed hair cells. There are large regional variations in cellular and synaptic architecture. Type I and type II hair cells are shorter, broader, and less densely packed in the central zone than in the intermediate and peripheral zones. Complex calyx endings are most common centrally. On average, there are 15-20 ribbon synapses and 25-30 calyceal invaginations in each type I hair cell. Synapses and invaginations are most numerous centrally. Central type II hair cells receive considerably fewer afferent boutons than do peripheral type II hair cells, but have similar numbers of ribbon synapses. The numbers are similar because central type II hair cells make more synapses with the outer faces of calyx endings and with individual afferent boutons. Most afferent boutons get one ribbon synapse. Boutons without ribbon synapses were only found peripherally, and boutons getting multiple synapses were most frequent centrally. Throughout the neuroepithelium, there is an average of three to four efferent boutons on each type II hair cell and calyx ending. Reciprocal synapses are rare. Most synaptic ribbons in type I hair cells are spherules; those in type II hair cells can be spherical or elongated and are particularly heterogeneous centrally. Consistent with the proposal that the crista is concentrically organized, the intermediate and peripheral zones are each similar in their cellular and synaptic architecture near the base and near the planum. An especially differentiated subzone may exist in the middle of the central zone.

  18. HMGB1 promotes cellular proliferation and invasion, suppresses cellular apoptosis in osteosarcoma.

    PubMed

    Meng, Qingbing; Zhao, Jie; Liu, Hongbing; Zhou, Guoyou; Zhang, Wensheng; Xu, Xingli; Zheng, Minqian

    2014-12-01

    Osteosarcoma is the most common primary malignant bone tumor in children and adolescents. Unfortunately, treatment failures are common due to the metastasis and chemoresistance, but the underlying molecular mechanism remains unclear. Accumulating evidence indicated that the deregulation of DNA-binding protein high-mobility group box 1 (HMGB1) was associated with the development of cancer. This study aimed to explore the expression of HMGB1 in osteosarcoma tissues and its correlation to the clinical pathology of osteosarcoma and to discuss the role of HMGB1 in the development of osteosarcoma. The results from RT-PCR and Western blot showed that the expression rate of HMGB1 messenger RNA (mRNA) and the expression of HMGB1 in the osteosarcoma tissues were significantly higher than those in normal bone tissue (p < 0.05), the expression rate of HMGB1 mRNA and the expression of HMGB1 in the carcinoma tissues with positive lung metastasis were significantly higher than those without lung metastasis (p < 0.05), and with increasing Enneking stage, the expression rate of HMGB1 mRNA and the expression of HMGB1 also increased (p < 0.05). In order to explore the role of HMGB1 in osteosarcoma, the expression of HMGB1 in the human osteosarcoma MG-63 cell line was downregulated by the technique of RNA interference. Western blot results showed that the protein expression of HMGB1 was significantly decreased in the MG-63 cells from HMGB1-siRNA transfection group (p < 0.05), which suggested that HMGB1 was successfully downregulated in the MG-63 cells. Then the changes in proliferation, apoptosis, and invasion of MG-63 cells were examined by MTT test, PI staining, annexin V staining, and transwell chamber assay. Results showed that the abilities of proliferation and invasion were suppressed in HMGB1 knockdown MG-63 cells, and the abilities of apoptosis were enhanced in HMGB1 knockdown MG-63 cells. The expression of cyclin D1, MMP-9 was downregulated in HMGB1 knockdown

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

    PubMed Central

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

    2017-01-01

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

  20. Regulation of cellular proliferation and intimal formation following balloon injury in atherosclerotic rabbit arteries.

    PubMed Central

    Simari, R D; San, H; Rekhter, M; Ohno, T; Gordon, D; Nabel, G J; Nabel, E G

    1996-01-01

    Injury to atherosclerotic arteries induces the expression of growth regulatory genes that stimulate cellular proliferation and intimal formation. Intimal expansion has been reduced in vivo in nonatherosclerotic balloon-injured arteries by transfer of genes that inhibit cell proliferation. It is not known, however, whether vascular cell proliferation can be inhibited after injury in more extensively diseased atherosclerotic arteries. Accordingly, the purpose of this study was to investigate whether expression of recombinant genes in atherosclerotic arteries after balloon injury could inhibit intimal cell proliferation. To test this hypothesis, we examined the response to balloon injury in atherosclerotic rabbit arteries after gene transfer of herpesvirus thymidine kinase gene (tk) and administration of ganciclovir. Smooth muscle cells from hyperlipidemic rabbit arteries infected with adenoviral vectors encoding tk were sensitive to ganciclovir, and bystander killing was observed in vitro. In atherosclerotic arteries, a human placental alkaline phosphatase reporter gene was expressed in intimal and medial smooth muscle cells and macrophages, identifying these cells as targets for gene transfer. Expression of tk in balloon-injured hyperlipidemic rabbit arteries followed by ganciclovir treatment resulted in a 64% reduction in intimal cell proliferation 7 d after gene transfer (P = 0.004), and a 35-49% reduction in internal area 21 d after gene transfer, compared with five different control groups (P < 0.05). Replication of smooth muscle cells and macrophages was inhibited by tk expression and ganciclovir treatment. These findings indicate that transfer of a gene that inhibits cellular proliferation limits the intimal area in balloon-injured atherosclerotic arteries. Molecular approaches to the inhibition of cell proliferation in atherosclerotic arteries constitute a possible treatment for vascular proliferative diseases. PMID:8690797

  1. Obesity and cancer: At the crossroads of cellular metabolism and proliferation

    PubMed Central

    O’Rourke, Robert W.

    2014-01-01

    Obesity is associated with an increased risk of cancer. The mechanisms underlying this association include but are not limited to increased systemic inflammation, an anabolic hormonal milieu, and adipocyte-cancer crosstalk, aberrant stimuli that conspire to promote neoplastic transformation. Cellular proliferation is uncoupled from nutrient availability in malignant cells, promoting tumor progression. Elucidation of the mechanisms underlying the obesity-cancer connection will lead to the development of novel metabolism-based agents for cancer prevention and treatment. PMID:25264328

  2. The Wnt signaling pathway in cellular proliferation and differentiation: A tale of two coactivators.

    PubMed

    Teo, Jia-Ling; Kahn, Michael

    2010-09-30

    Wnt signaling pathways play divergent roles during development, normal homeostasis and disease. The responses that result from the activation of the pathway control both proliferation and differentiation. Tight regulation and controlled coordination of the Wnt signaling cascade is required to maintain the balance between proliferation and differentiation. The non-redundant roles of the coactivator proteins CBP and p300, within the context of Wnt signaling are discussed. We highlight their roles as integrators of the various inputs that a cell receives to elicit the correct and coordinated response. We propose that essentially all cellular information - i.e. from other signaling pathways, nutrient levels, etc. - is funneled down into a choice of coactivators usage, either CBP or p300, by their interacting partner beta-catenin (or catenin-like molecules in the absence of beta-catenin) to make the critical decision to either remain quiescent, or once entering cycle to proliferate without differentiation or to initiate the differentiation process.

  3. Cellular automata model for human articular chondrocytes migration, proliferation and cell death: An in vitro validation.

    PubMed

    Vaca-González, J J; Gutiérrez, M L; Guevara, J M; Garzón-Alvarado, D A

    2016-01-07

    Articular cartilage is characterized by low cell density of only one cell type, chondrocytes, and has limited self-healing properties. When articular cartilage is affected by traumatic injuries, a therapeutic strategy such as autologous chondrocyte implantation is usually proposed for its treatment. This approach requires in vitro chondrocyte expansion to yield high cell number for cell transplantation. To improve the efficiency of this procedure, it is necessary to assess cell dynamics such as migration, proliferation and cell death during culture. Computational models such as cellular automata can be used to simulate cell dynamics in order to enhance the result of cell culture procedures. This methodology has been implemented for several cell types; however, an experimental validation is required for each one. For this reason, in this research a cellular automata model, based on random-walk theory, was devised in order to predict articular chondrocyte behavior in monolayer culture during cell expansion. Results demonstrated that the cellular automata model corresponded to cell dynamics and computed-accurate quantitative results. Moreover, it was possible to observe that cell dynamics depend on weighted probabilities derived from experimental data and cell behavior varies according to the cell culture period. Thus, depending on whether cells were just seeded or proliferated exponentially, culture time probabilities differed in percentages in the CA model. Furthermore, in the experimental assessment a decreased chondrocyte proliferation was observed along with increased passage number. This approach is expected to having other uses as in enhancing articular cartilage therapies based on tissue engineering and regenerative medicine.

  4. Ionizing irradiation inhibits keloid fibroblast cell proliferation and induces premature cellular senescence.

    PubMed

    Ji, Jiang; Tian, Ye; Zhu, Ya-qun; Zhang, Li-yuan; Ji, Sheng-jun; Huan, Jian; Zhou, Xiao-zhong; Cao, Jian-ping

    2015-01-01

    Keloids are one of the common refractory conditions in dermatology and aesthetic plastic surgery. The most effective treatment is superficial radiotherapy followed by surgical removal. The rate of recurrence is strongly associated with the total dose of ionizing irradiation, and the underlying mechanism remains unclear. In this study, we used primary keloid fibroblasts (KFb) isolated from patient samples to investigate the effects of X-ray radiation on cell proliferation, cell toxicity and cell cycle, as detected by CCK-8 assay kit and flow cytometer. In addition, we examined senescence-associated β-galactosidase activity and the associated gene expression using real-time polymerase chain reaction and western blot in KFb exposed to X-ray radiation. X-ray radiation inhibited cell proliferation and induced cell senescence in KFb in a dose-dependent manner. Inhibition of cell proliferation and induction of cellular senescence were mediated by interruption of the cell cycle with an extended G0/G1 phase. Furthermore, the expressions of senescence-associated genes p21, p16 and p27 were upregulated both at mRNA and protein levels in KFb exposed to X-ray radiation. Taken together, our data indicate that X-ray radiation may prevent the recurrence of keloids by controlling fibroblast proliferation, arresting the cell cycle and inducing premature cellular senescence. © 2014 Japanese Dermatological Association.

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

    SciTech Connect

    Catania, Annunziata; Iavarone, Carlo; Carlomagno, Stella M.; Chiariello, Mario . E-mail: chiariel@unina.it

    2006-05-05

    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.

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

    PubMed

    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.

  7. Knockdown of Gab1 Inhibits Cellular Proliferation, Migration, and Invasion in Human Oral Squamous Carcinoma Cells.

    PubMed

    Xu, Luyong; Li, Jie; Kuang, Zheng; Kuang, Yan; Wu, Hong

    2017-09-06

    Grb2-associated binder 1 (Gab1) is often aberrant in cancerous cells and tissues, whose alteration is to be responsiblefor aggressive phenotypes. In this study, we examined the Gab1 expression in human oral squamous cell carcinoma (OSCC) tissues and investigated the cellular and molecular effect of Gab1 on migration, invasion and cell growth of OSCC cell lines SCC15 and SCC25. We found Gab1 was over-expressed in OSCC tissues and cells, which is related to the protein levels of various molecules associated with cellular proliferation, migration, and invasion. Functional assays identified that Gab1 overexpression promoted cell proliferation and invasion of OSCC cells, and inhibited cell apoptosis in SCC15 and SCC25 cell lines. On the other hand, Gab1 silencing affected the proliferation and invasion of OSCC cells, and induced cell apoptosis. Western blot assay identified that Gab1 overexpression suppressed the expression of Cdc20 homologue-1 (Cdh1), and then promoted cell invasion in OSCC cells. Furthermore, Gab1-mediated Cdh1 down-regulation was significantly reversed when cells were subjected to the inhibitor of p-Akt. In conclusions, these results suggested that Gab1 induced malignant progression of OSCC cells probably via activating of the Akt/Cdh1 signaling pathway. Thus, Gab1 may be a potential therapeutic target in the treatment of OSCC patients.

  8. Rho-kinase inhibitor Y-27632 increases cellular proliferation and migration in human foreskin fibroblast cells.

    PubMed

    Piltti, Juha; Varjosalo, Markku; Qu, Chengjuan; Häyrinen, Jukka; Lammi, Mikko J

    2015-09-01

    The idea of direct differentiation of somatic cells into other differentiated cell types has attracted a great interest recently. Rho-kinase inhibitor Y-27632 (ROCKi) is a potential drug molecule, which has been reported to support the gene expressions typical for the chondrocytes, thus restricting their phenotypic conversion to fibroblastic cells upon the cellular expansion. In this study, we have investigated the short-term biological responses of ROCKi to human primary foreskin fibroblasts. The fibroblast cells were exposed to 1 and 10 μM ROCKi treatments. A proteomics analysis revealed expression changes of 56 proteins, and a further protein pathway analysis suggested their association with the cell morphology, the organization, and the increased cellular movement and the proliferation. These functional responses were confirmed by a Cell-IQ time-lapse imaging analysis. Rho-kinase inhibitor treatment increased the cellular proliferation up to twofold during the first 12 h, and a wound model based migration assay showed 50% faster filling of the mechanically generated wound area. Additionally, significantly less vinculin-associated focal adhesions were present in the ROCKi-treated cells. Despite the marked changes in the cell behavior, ROCKi was not able to induce the expression of the chondrocyte-specific genes, such as procollagen α1 (II) and aggrecan.

  9. Silibinin inhibits HIV-1 infection by reducing cellular activation and proliferation.

    PubMed

    McClure, Janela; Lovelace, Erica S; Elahi, Shokrollah; Maurice, Nicholas J; Wagoner, Jessica; Dragavon, Joan; Mittler, John E; Kraft, Zane; Stamatatos, Leonidas; Stamatatos, Leonidis; Horton, Helen; De Rosa, Stephen C; Coombs, Robert W; Polyak, Stephen J

    2012-01-01

    Purified silymarin-derived natural products from the milk thistle plant (Silybum marianum) block hepatitis C virus (HCV) infection and inhibit T cell proliferation in vitro. An intravenous formulation of silibinin (SIL), a major component of silymarin, displays anti-HCV effects in humans and also inhibits T-cell proliferation in vitro. We show that SIL inhibited replication of HIV-1 in TZM-bl cells, PBMCs, and CEM cells in vitro. SIL suppression of HIV-1 coincided with dose-dependent reductions in actively proliferating CD19+, CD4+, and CD8+ cells, resulting in fewer CD4+ T cells expressing the HIV-1 co-receptors CXCR4 and CCR5. SIL inhibition of T-cell growth was not due to cytotoxicity measured by cell cycle arrest, apoptosis, or necrosis. SIL also blocked induction of the activation markers CD38, HLA-DR, Ki67, and CCR5 on CD4+ T cells. The data suggest that SIL attenuated cellular functions involved in T-cell activation, proliferation, and HIV-1 infection. Silymarin-derived compounds provide cytoprotection by suppressing virus infection, immune activation, and inflammation, and as such may be relevant for both HIV mono-infected and HIV/HCV co-infected subjects.

  10. Osteopontin Stimulates Preneoplastic Cellular Proliferation Through Activation of the MAPK Pathway

    PubMed Central

    Ruhland, Megan K.; Pazolli, Ermira; Lind, Anne C.; Stewart, Sheila A.

    2013-01-01

    Alterations in the microenvironment collaborate with cell autonomous mutations during the transformation process. Indeed, cancer- associated fibroblasts (CAF) and senescent fibroblasts stimulate tumorigenesis in xenograft models. Because senescent fibroblasts accumulate with age, these findings suggest that they contribute to age-related increases in tumorigenesis. Previously we demonstrated that senescent-associated stromal derived osteopontin (OPN) contributes to preneoplastic cell growth in vitro and in xenografts, suggesting that it impacts neoplastic progression. Analysis of fibroblasts within premalignant and malignant skin lesions ranging from solar/actinic keratosis (AK) to squamous cell carcinoma (SCC) revealed they express OPN. Given the stromal expression of OPN, we investigated how OPN impacts preneoplastic cell growth. We demonstrate that OPN promotes preneoplastic keratinocyte cellular proliferation and cell survival through the CD44 cell receptor and activation of the MAPK pathway. These data suggest that stromal-derived OPN impacts tumorigenesis by stimulating preneoplastic cell proliferation thus allowing expansion of initiated cells in early lesions. PMID:21673011

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

    PubMed Central

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

    2014-01-01

    Objective(s): 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). Methods: 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. Results: 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%). Conclusion: 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. PMID:27408853

  12. [Cell signaling pathways interaction in cellular proliferation: Potential target for therapeutic interventionism].

    PubMed

    Valdespino-Gómez, Víctor Manuel; Valdespino-Castillo, Patricia Margarita; Valdespino-Castillo, Víctor Edmundo

    2015-01-01

    Nowadays, cellular physiology is best understood by analysing their interacting molecular components. Proteins are the major components of the cells. Different proteins are organised in the form of functional clusters, pathways or networks. These molecules are ordered in clusters of receptor molecules of extracellular signals, transducers, sensors and biological response effectors. The identification of these intracellular signaling pathways in different cellular types has required a long journey of experimental work. More than 300 intracellular signaling pathways have been identified in human cells. They participate in cell homeostasis processes for structural and functional maintenance. Some of them participate simultaneously or in a nearly-consecutive progression to generate a cellular phenotypic change. In this review, an analysis is performed on the main intracellular signaling pathways that take part in the cellular proliferation process, and the potential use of some components of these pathways as target for therapeutic interventionism are also underlined. Copyright © 2015 Academia Mexicana de Cirugía A.C. Published by Masson Doyma México S.A. All rights reserved.

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

    PubMed

    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

  14. Ultrastructural features of the differentiating thyroid primordium in the sand lizard (Lacerta agilis L.) from the differentiation of the cellular cords to the formation of the follicular lumen.

    PubMed

    Rupik, Weronika; Kowalska, Magdalena; Swadźba, Elwira; Maślak, Robert

    2016-04-01

    The differentiation of the thyroid primordium of lacertilian species is poorly understood. The present study reports on the ultrastructural analysis of the developing thyroid primordium in the sand lizard (Lacerta agilis) during the early stages of differentiation. The early thyroid primordium of sand lizard embryos was composed of cellular cords that contained single cells with a giant lipid droplet, which were eliminated by specific autophagy (lipophagy). The follicular lumens at the periphery of the primordium differentiated even before the division of the cellular cords. When the single cells within the cords started to die through paraptosis, the adjacent cells started to polarise and junctional complexes began to form around them. After polarisation and clearing up after the formation of the lumens, the cellular cords divided into definitive follicles. The cellular cords in the central part of the primordium started to differentiate later than those at the periphery. The cellular cords divided into presumptive follicles first and only later differentiated into definitive follicles. During this process, a population of centrally located cells was removed through apoptosis to form the lumen. Although the follicular lumen in sand lizard embryos is differentiated by cavitation similar to that in the grass snake, there were very important differences during the early stages of the differentiation of the cellular cords and the formation of the thyroid follicles. Copyright © 2016 Elsevier GmbH. All rights reserved.

  15. Merkel Cell Polyomavirus Large T Antigen Disrupts Host Genomic Integrity and Inhibits Cellular Proliferation

    PubMed Central

    Li, Jing; Wang, Xin; Diaz, Jason; Tsang, Sabrina H.; Buck, Christopher B.

    2013-01-01

    Clonal integration of Merkel cell polyomavirus (MCV) DNA into the host genome has been observed in at least 80% of Merkel cell carcinoma (MCC). The integrated viral genome typically carries mutations that truncate the C-terminal DNA binding and helicase domains of the MCV large T antigen (LT), suggesting a selective pressure to remove this MCV LT region during tumor development. In this study, we show that MCV infection leads to the activation of host DNA damage responses (DDR). This activity was mapped to the C-terminal helicase-containing region of the MCV LT. The MCV LT-activated DNA damage kinases, in turn, led to enhanced p53 phosphorylation, upregulation of p53 downstream target genes, and cell cycle arrest. Compared to the N-terminal MCV LT fragment that is usually preserved in mutants isolated from MCC tumors, full-length MCV LT shows a decreased potential to support cellular proliferation, focus formation, and anchorage-independent cell growth. These apparently antitumorigenic effects can be reversed by a dominant-negative p53 inhibitor. Our results demonstrate that MCV LT-induced DDR activates p53 pathway, leading to the inhibition of cellular proliferation. This study reveals a key difference between MCV LT and simian vacuolating virus 40 LT, which activates a DDR but inhibits p53 function. This study also explains, in part, why truncation mutations that remove the MCV LT C-terminal region are necessary for the oncogenic progression of MCV-associated cancers. PMID:23760247

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

    PubMed

    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.

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

    PubMed Central

    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 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. PMID:26544514

  18. Commonly consumed and specialty dietary mushrooms reduce cellular proliferation in MCF-7 human breast cancer cells.

    PubMed

    Martin, Keith R; Brophy, Sara K

    2010-11-01

    Worldwide, over one million women will be newly diagnosed with breast cancer in the next year. Moreover, breast cancer is the second leading cause of cancer death in the USA. An accumulating body of evidence suggests that consumption of dietary mushrooms can protect against breast cancer. In this study, we tested and compared the ability of five commonly consumed or specialty mushrooms to modulate cell number balance in the cancer process using MCF-7 human breast cancer cells. Hot water extracts (80°C for 2 h) of maitake (MT, Grifola frondosa), crimini (CRIM, Agaricus bisporus), portabella (PORT, Agaricus bisporus), oyster (OYS, Pleurotus ostreatus) and white button (WB, Agaricus bisporus) mushrooms or water alone (5% v/v) were incubated for 24 h with MCF-7 cells. Cellular proliferation determined by bromodeoxyuridine incorporation was significantly (P < 0.05) reduced up to 33% by all mushrooms, with MT and OYS being the most effective. MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) reduction, an often used mitochondrion-dependent marker of proliferation, was unchanged although decreased (P > 0.05) by 15% with OYS extract. Lactate dehydrogenase release, as a marker of necrosis, was significantly increased after incubation with MT but not with other test mushrooms. Furthermore, MT extract significantly increased apoptosis, or programmed cell death, as determined by terminal deoxynucleotidyl end labeling method, whereas other test mushrooms displayed trends of ∼15%. The total numbers of cells per flask, determined by hemacytometry, were not different from control cultures. Overall, all test mushrooms significantly suppressed cellular proliferation, with MT further significantly inducing apoptosis and cytotoxicity in human breast cancer cells. This suggests that both common and specialty mushrooms may be chemoprotective against breast cancer.

  19. Arecoline augments cellular proliferation in the prostate gland of male Wistar rats

    SciTech Connect

    Saha, Indraneel; Chatterjee, Aniruddha; Mondal, Anushree; Maiti, Bishwa Ranjan; Chatterji, Urmi

    2011-09-01

    Areca nut chewing is the fourth most popular habit in the world due to its effects as a mild stimulant, causing a feeling of euphoria and slightly heightened alertness. Areca nuts contain several alkaloids and tannins, of which arecoline is the most abundant and known to have several adverse effects in humans, specially an increased risk of oral cancer. On evaluating the effects of arecoline on the male endocrine physiology in Wistar rats, it was found that arecoline treatment led to an overall enlargement and increase in the wet weight of the prostate gland, and a two-fold increase in serum gonadotropin and testosterone levels. Since the prostate is a major target for testosterone, the consequences of arecoline consumption were studied specifically in the prostate gland. Arecoline treatment led to an increase in the number of rough endoplasmic reticulum and reduction of secretory vesicles, signifying a hyperactive state of the prostate. Increased expression of androgen receptors in response to arecoline allowed for enhanced effect of testosterone in the prostate of treated animals, which augmented cell proliferation, subsequently confirmed by an increase in the expression of Ki-67 protein. Cellular proliferation was also the outcome of concomitant over expression of the G{sub 1}-to-S cell cycle regulatory proteins, cyclin D1 and CDK4, both at the transcriptional and translational levels. Taken together, the findings provide the first evidence that regular use of arecoline may lead to prostatic hyperplasia and hypertrophy, and eventually to disorders associated with prostate enlargement. - Highlights: > Effect of arecoline was investigated on the endocrine physiology of male Wistar rats. > Increase observed in prostate size, wet weight, serum testosterone and gonadotropins. > Arecoline increased RER, expression of androgen receptor and cellular proliferation. > Upregulation of cyclin D1 and CDK4 seen at transcriptional and translational levels. > It may cause

  20. Modulation of 17β-Estradiol Signaling on Cellular Proliferation by Caveolin-2.

    PubMed

    Totta, Pierangela; Gionfra, Fabio; Busonero, Claudia; Acconcia, Filippo

    2016-06-01

    The sex hormone 17β-estradiol (E2) exerts pleiotropic effects by binding to the ligand-activated transcription factor estrogen receptor α (ERα). The E2:ERα complex regulates several physiological processes, including cell survival and proliferation, through transcriptional effects (i.e., estrogen responsive element [ERE]-based gene transcription) and non-transcriptional membrane-initiated effects (i.e., the activation of extra-nuclear signaling cascades), which derive from the activation of the pool of ERα that is localized to plasma membrane caveolae. Caveolae are ω-shaped membrane sub-domains that are composed of scaffold proteins named caveolins (i.e., caveolin-1, caveolin-2, and caveolin-3). Although caveolin-3 is exclusively expressed in muscles, caveolin-1 and caveolin-2 are co-expressed in all human tissues. From a functional point of view, caveolin-2 can operate both dependently on and independently of caveolin-1, which is the main coat component of caveolae. Interestingly, while a functional interplay between caveolin-1 and ERα has been reported in the control of E2-induced physiological effects, the role of caveolin-2 in E2:ERα signaling within the cell remains poorly understood. This study shows that siRNA-mediated caveolin-2 depletion in breast ductal carcinoma cells (MCF-7) reduces E2-induced ERα phosphorylation at serine residue 118 (S118), controls intracellular receptor levels, precludes ERα-mediated extra-nuclear activation of signaling pathways, reduces ERα transcriptional activity, and prevents cellular proliferation. Meanwhile, the impact of caveolin-1 depletion on ERα signaling in MCF-7 cells is shown to be similar to that elicited by siRNA-mediated caveolin-2 depletion. Altogether, these data demonstrate that caveolin-2 expression is necessary for the control of E2-dependent cellular proliferation.

  1. Graphene Enhances Cellular Proliferation through Activating the Epidermal Growth Factor Receptor.

    PubMed

    Liu, Wei; Sun, Cheng; Liao, Chunyang; Cui, Lin; Li, Haishan; Qu, Guangbo; Yu, Wenlian; Song, Naining; Cui, Yuan; Wang, Zheng; Xie, Wenping; Chen, Huiming; Zhou, Qunfang

    2016-07-27

    Graphene has promising applications in food packaging, water purification, and detective sensors for contamination monitoring. However, the biological effects of graphene are not fully understood. It is necessary to clarify the potential risks of graphene exposure to humans through diverse routes, such as foods. In the present study, graphene, as the model nanomaterial, was used to test its potential effects on the cell proliferation based on multiple representative cell lines, including HepG2, A549, MCF-7, and HeLa cells. Graphene was characterized by Raman spectroscopy, particle size analysis, atomic force microscopy, and transmission electron microscopy. The cellular responses to graphene exposure were evaluated using flow cytometry, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, and alamarBlue assays. Rat cerebral astrocyte cultures, as the non-cancer cells, were used to assess the potential cytotoxicity of graphene as well. The results showed that graphene stimulation enhanced cell proliferation in all tested cell cultures and the highest elevation in cell growth was up to 60%. A western blot assay showed that the expression of epidermal growth factor (EGF) was upregulated upon graphene treatment. The phosphorylation of EGF receptor (EGFR) and the downstream proteins, ShC and extracellular regulating kinase (ERK), were remarkably induced, indicating that the activation of the mitogen-activated protein kinase (MAPK)/ERK signaling pathway was triggered. The activation of PI3 kinase p85 and AKT showed that the PI3K/AKT signaling pathway was also involved in graphene-induced cell proliferation, causing the increase of cell ratios in the G2/M phase. No influences on cell apoptosis were observed in graphene-treated cells when compared to the negative controls, proving the low cytotoxicity of this emerging nanomaterial. The findings in this study revealed the potential cellular biological effect of graphene, which may give useful hints on its biosafety

  2. A Genetic and Functional Relationship between T Cells and Cellular Proliferation in the Adult Hippocampus

    PubMed Central

    Huang, Guo-Jen; Smith, Adrian L.; Gray, Daniel H.D.; Cosgrove, Cormac; Singer, Benjamin H.; Edwards, Andrew; Sim, Stuart; Parent, Jack M.; Johnsen, Alyssa; Mott, Richard; Mathis, Diane; Klenerman, Paul; Benoist, Christophe; Flint, Jonathan

    2010-01-01

    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. PMID:21179499

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

    SciTech Connect

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

    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.

  4. Differential impact of nicotine on cellular proliferation and cytokine production by LPS-stimulated murine splenocytes.

    PubMed

    Hakki, A; Hallquist, N; Friedman, H; Pross, S

    2000-06-01

    The immunoregulatory effects of nicotine have not been fully clarified and the reported data are often conflicting. The present study investigated the role of nicotine as an immunomodulator of murine splenocytes stimulated by lipopolysaccharide (LPS), the endotoxin component of gram-negative bacteria. BALB/c female mice of two different ages, young (2-3 months) and old (18-22 months), were used. The cells were incubated with nicotine at two different time points, 3 h pre-incubation and concurrent incubation relevant to LPS stimulation, before further incubation for 48 or 72 h. Treatment of murine splenocytes with nicotine showed an impact on cellular proliferation as well as on the production of the pro-inflammatory cytokines, tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6). The results indicated that nicotine significantly inhibited cellular proliferation of murine splenocytes in a concentration-related manner (32, 64 and 128 microg/ml). Timing of nicotine exposure prior to LPS stimulation was critical in terms of immunological impact on cytokine production. TNF-alpha and IL-6 production were significantly enhanced by 1 microg/ml of nicotine when cells were pre-incubated with nicotine for 3 h compared to concurrent incubation relative to LPS stimulation. The alteration in cytokine production varied with the age of the mouse. TNF-alpha production was significantly inhibited by nicotine in young mice, while IL-6 production was significantly inhibited by nicotine in old mice. Since any immunomodulation that alters the profile of these cytokines may cause an imbalance in the immune system impinging on health status, these findings may be important when dealing with the concept of nicotine as a therapeutic agent.

  5. Nerve growth factor stimulates cellular proliferation of human epithelial ovarian cancer.

    PubMed

    Urzua, U; Tapia, V; Geraldo, M P; Selman, A; Vega, M; Romero, C

    2012-09-01

    Due to its ability to induce vascular endothelial growth factor expression and proliferation, migration, and vasculogenesis of endothelial cells, nerve growth factor (NGF) has been considered as an angiogenic factor in epithelial ovarian cancer (EOC). In this work, we evaluated the angiogenic and proliferative mRNA expression profiles of EOC and addressed the responsiveness of EOC explants to NGF stimulation. Twenty EOC samples were obtained from Obstetrics and Gynecology Department, University of Chile's Clinical Hospital. Global gene expression profiles of selected poorly differentiated serous EOC samples were obtained with DNA oligonucleotide microarrays. In addition, EOC explants were subjected to NGF stimulation and levels of p-AKT, BAX, BCL2, Ki-67, c-MYC, and FOXL2 proteins were determined by immunohistochemistry. Results showed that mRNAs coding for specific transcriptional regulators and antiapoptotic components of the NGF signaling pathway were upregulated in EOC cells. At the protein level, key members of the NGF pathway including p-AKT, BCL2/BAX, Ki-67, and c-MYC were found increased, while FOXL2 was decreased in response to NGF stimulation. These findings strongly suggest that NGF stimulates cellular proliferation of human EOC. © Georg Thieme Verlag KG Stuttgart · New York.

  6. Cellular proliferation markers in peripheral and central fibromas: a comparative study

    PubMed Central

    GARCIA, Bruna Gonçalves; CALDEIRA, Patrícia Carlos; JOHANN, Aline Cristina Batista Rodrigues; de SOUSA, Suzana Cantanhede Orsini Machado; CALIARI, Marcelo Vidigal; do CARMO, Maria Auxiliadora Vieira; MESQUITA, Ricardo Alves

    2013-01-01

    Objective: To perform a comparative study of the cellular proliferation in the peripheral and central fibromas. Material and Methods: Immunohistochemistry for PCNA and the AgNOR technique were performed in 9 cases of peripheral odontogenic fibroma (POF), in 4 cases of odontogenic fibroma (OdF), in 8 cases of peripheral ossifying fibroma (PEOF) and 7 cases of ossifying fibroma (OsF). The Kruskal-Wallis and Mann-Whitney tests were used for the statistical analyses. Results: Mesenchymal component of the central lesions presented a higher mean number of AgNOR per nucleus and PCNA index than did the peripheral lesions (P≤0.05). The mean number of AgNOR per nucleus in the epithelial component proved to be higher in the OdF than in the POF (P≤0.05). The mesenchymal and epithelial components presented similar mean numbers of AgNOR per nucleus and PCNA index in the OdF, as well as a similar mean number of AgNOR per nucleus in the POF. Conclusions: The mesenchymal component may well play a role in the differences between the biological behaviour of the central lesions as compared to the peripheral lesions. Moreover, considering that the epithelial and mesenchymal components in odontogenic fibromas presented a similar proliferation index, more research is warranted to understand the true role of the epithelial components, which are believed to be inactive in nature, as well as in the development and biological behaviour of these lesions. PMID:23739858

  7. Radiation effects on cellularity, proliferation and EGFR expression in mouse bladder urothelium.

    PubMed

    Jaal, Jana; Dörr, Wolfgang

    2010-04-01

    This study was designed to determine changes in cell numbers, proliferation (using Ki-67) and EGFR expression in mouse bladder urothelium during the early and late radiation response. Groups of mice were irradiated with a single dose of 20 Gy and assayed 0-360 days later. Urothelial cells were counted. After immunohistochemistry, the absolute and relative numbers of Ki-67(+) and EGFR(+) cells were analyzed. Radiation exposure resulted in a decrease in total urothelial cell numbers to 49% by day 31, with restoration of cellularity by day 180. In contrast, at day 360, an increase in total cell number (143%) was seen. Slightly increased Ki-67 expression was found at days 120 and 180 after treatment, followed by a pronounced elevation at days 240 and 360. Compared to controls, higher EGFR expression was detected up to day 360 after irradiation. A positive correlation was found between total urothelial cells numbers and Ki-67 as well as EGFR expression. Radiation exposure results in an increased urothelial expression of EGFR that precedes urothelial restoration, indicating a contribution of the EGF/EGFR system to urothelial proliferation and differentiation. Further studies are needed to evaluate the impact of EGFR inhibition on radiation effects in the urinary bladder.

  8. Structural Development, Cellular Differentiation and Proliferation of the Respiratory Epithelium in the Bovine Fetal Lung.

    PubMed

    Drozdowska, J; Cousens, C; Finlayson, J; Collie, D; Dagleish, M P

    2016-01-01

    Fetal bovine lung samples of 11 different gestational ages were assigned to a classical developmental stage based on histological morphology. Immunohistochemistry was used to characterize the morphology of forming airways, proliferation rate of airway epithelium and the presence of epithelial cell types (i.e. ciliated cells, club cells, neuroepithelial cells (NECs) and type II pneumocytes). Typical structural organization of pseudoglandular (84-98 days gestational age [DGA]), canalicular (154-168 DGA) and alveolar (224-266 DGA) stages was recognized. In addition, transitional pseudoglandular-canalicular (112-126 DGA) and canalicular-saccular (182 DGA) morphologies were present. The embryonic stage was not observed. A significantly (P <0.05) higher proliferation rate of pulmonary epithelium, on average 5.5% and 4.4% in bronchi and bronchioles, respectively, was present in the transitional pseudoglandular-canalicular phase (112-126 DGA) compared with all other phases, while from 8 weeks before term (224-266 DGA) proliferation had almost ceased. The first epithelial cells identified by specific marker proteins in the earliest samples available for study (84 DGA) were ciliated cells and NECs. Club cells were present initially at 112 DGA and type II pneumocytes at 224 DGA. At the latest time points (224-226 DGA) these latter cell types were still present at a much lower percentage compared with adult cattle. This study characterized bovine fetal lung development by histological morphology and cellular composition of the respiratory epithelium and suggests that the apparent structural anatomical maturity of the bovine lung at term is not matched by functional maturity of the respiratory epithelium.

  9. Electron beam ionization induced oxidative enzymatic activities in pepper (Capsicum annuum L.), associated with ultrastructure cellular damages.

    PubMed

    Martínez-Solano, J R; Sánchez-Bel, P; Egea, I; Olmos, E; Hellin, E; Romojaro, F

    2005-11-02

    Mature green pepper fruits (Capsicum annuum L.) were subjected to ionizing radiation, in the range of 1-7 kGy, with accelerated electrons. Ultrastructural changes by electron microscopy, and the activity of several oxidative metabolism-related enzymes such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), guaicol peroxidase (POX), and lipoxygenase (LOX), were determined in pericarp tissue just after the ionization treatment and during postionization storage at 7 degrees C followed by 3 days at 20 degrees C. Changes in oxidative stress during the ionization treatment was assessed by the accumulation of malondyaldehide (MDA), a lipid peroxidation product. The ionization induced modifications in the cell ultrastructure, a moderate separation of the plasma membrane from the cell wall being observed for all doses. At 5 and 7 kGy, peroxisomes were not detected and the structures of the chloroplast and vacuoles were seriously damaged. Lipid peroxidation and lipoxygenase activity increased with the ionization dose, staying constant and decreasing, respectively, during the storage period. Conversely, catalase, ascorbate peroxidase, and superoxide dismutase had lower values than in nonionized fruits and, in general, their values did not change or diminished slightly from the seventh day of storage. Peroxidase exhibited an increase in activity with the ionization dose, although these was not a linear relationship, with higher values at 3kGy. Ionization of pepper, especially at doses of 5 and 7 kGy, caused a significant oxidative damage in the fruit, since it increased oxidation and decreased the antioxidant enzymatic defense systems causing ultrastructural changes at cell level.

  10. Adenovirus type 5 exerts genome-wide control over cellular programs governing proliferation, quiescence, and survival

    PubMed Central

    Miller, Daniel L; Myers, Chad L; Rickards, Brenden; Coller, Hilary A; Flint, S Jane

    2007-01-01

    Background Human adenoviruses, such as serotype 5 (Ad5), encode several proteins that can perturb cellular mechanisms that regulate cell cycle progression and apoptosis, as well as those that mediate mRNA production and translation. However, a global view of the effects of Ad5 infection on such programs in normal human cells is not available, despite widespread efforts to develop adenoviruses for therapeutic applications. Results We used two-color hybridization and oligonucleotide microarrays to monitor changes in cellular RNA concentrations as a function of time after Ad5 infection of quiescent, normal human fibroblasts. We observed that the expression of some 2,000 genes, about 10% of those examined, increased or decreased by a factor of two or greater following Ad5 infection, but were not altered in mock-infected cells. Consensus k-means clustering established that the temporal patterns of these changes were unexpectedly complex. Gene Ontology terms associated with cell proliferation were significantly over-represented in several clusters. The results of comparative analyses demonstrate that Ad5 infection induces reversal of the quiescence program and recapitulation of the core serum response, and that only a small subset of the observed changes in cellular gene expression can be ascribed to well characterized functions of the viral E1A and E1B proteins. Conclusion These findings establish that the impact of adenovirus infection on host cell programs is far greater than appreciated hitherto. Furthermore, they provide a new framework for investigating the molecular functions of viral early proteins and information relevant to the design of conditionally replicating adenoviral vectors. PMID:17430596

  11. Changes in cellular proliferation and plasma products are associated with liver failure

    PubMed Central

    Melgaço, Juliana Gil; Soriani, Frederico Marianetti; Sucupira, Pedro Henrique Ferreira; Pinheiro, Leonardo Assaf; Vieira, Yasmine Rangel; de Oliveira, Jaqueline Mendes; Lewis-Ximenez, Lia Laura; Araújo, Cristina Carvalho Vianna; Pacheco-Moreira, Lúcio Filgueiras; Menezes, Gustavo Batista; Cruz, Oswaldo Gonçalves; Vitral, Claudia Lamarca; Pinto, Marcelo Alves

    2016-01-01

    AIM To study the differences in immune response and cytokine profile between acute liver failure and self-limited acute hepatitis. METHODS Forty-six patients with self-limited acute hepatitis (AH), sixteen patients with acute liver failure (ALF), and twenty-two healthy subjects were involved in this study. The inflammatory and anti-inflammatory products in plasma samples were quantified using commercial enzyme-linked immunoassays and quantitative real-time PCR. The cellular immune responses were measured by proliferation assay using flow cytometry. The groups were divided into viral- and non-viral-induced self-limited AH and ALF. Thus, we worked with five groups: Hepatitis A virus (HAV)-induced self-limited acute hepatitis (HAV-AH), HAV-induced ALF (HAV-ALF), non-viral-induced self-limited acute hepatitis (non-viral AH), non-viral-induced acute liver failure (non-viral ALF), and healthy subjects (HC). Comparisons among HAV and non-viral-induced AH and ALF were performed. RESULTS The levels of mitochondrial DNA (mtDNA) and the cytokines investigated [interleukin (IL)-6, IL-8, IL-10, interferon gamma, and tumor necrosis factor] were significantly increased in ALF patients, independently of etiology (P < 0.05). High plasma mtDNA and IL-10 were the best markers associated with ALF [mtDNA: OR = 320.5 (95%CI: 14.42-7123.33), P < 0.0001; and IL-10: OR = 18.8 (95%CI: 1.38-257.94), P = 0.028] and death [mtDNA: OR = 12.1 (95%CI: 2.57-57.07), P = 0.002; and IL-10: OR = 8.01 (95%CI: 1.26-50.97), P = 0.027]. In the cellular proliferation assay, NKbright, NKT and regulatory T cells (TReg) predominated in virus-specific stimulation in HAV-induced ALF patients with an anergic behavior in the cellular response to mitotic stimulation. Therefore, in non-viral-induced ALF, anergic behavior of activated T cells was not observed after mitotic stimulation, as expected and as described by the literature. CONCLUSION mtDNA and IL-10 may be predictors of ALF and death. TReg cells are

  12. Effects of antibacterial mineral leachates on the cellular ultrastructure, morphology, and membrane integrity of Escherichia coli and methicillin-resistant Staphylococcus aureus

    PubMed Central

    2010-01-01

    Background We have previously identified two mineral mixtures, CB07 and BY07, and their respective aqueous leachates that exhibit in vitro antibacterial activity against a broad spectrum of pathogens. The present study assesses cellular ultrastructure and membrane integrity of methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli after exposure to CB07 and BY07 aqueous leachates. Methods We used scanning and transmission electron microscopy to evaluate E. coli and MRSA ultrastructure and morphology following exposure to antibacterial leachates. Additionally, we employed Baclight LIVE/DEAD staining and flow cytometry to investigate the cellular membrane as a possible target for antibacterial activity. Results Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) imaging of E. coli and MRSA revealed intact cells following exposure to antibacterial mineral leachates. TEM images of MRSA showed disruption of the cytoplasmic contents, distorted cell shape, irregular membranes, and distorted septa of dividing cells. TEM images of E. coli exposed to leachates exhibited different patterns of cytoplasmic condensation with respect to the controls and no apparent change in cell envelope structure. Although bactericidal activity of the leachates occurs more rapidly in E. coli than in MRSA, LIVE/DEAD staining demonstrated that the membrane of E. coli remains intact, while the MRSA membrane is permeabilized following exposure to the leachates. Conclusions These data suggest that the leachate antibacterial mechanism of action differs for Gram-positive and Gram-negative organisms. Upon antibacterial mineral leachate exposure, structural integrity is retained, however, compromised membrane integrity accounts for bactericidal activity in Gram-positive, but not in Gram-negative cells. PMID:20846374

  13. Arecoline augments cellular proliferation in the prostate gland of male Wistar rats.

    PubMed

    Saha, Indraneel; Chatterjee, Aniruddha; Mondal, Anushree; Maiti, Bishwa Ranjan; Chatterji, Urmi

    2011-09-01

    Areca nut chewing is the fourth most popular habit in the world due to its effects as a mild stimulant, causing a feeling of euphoria and slightly heightened alertness. Areca nuts contain several alkaloids and tannins, of which arecoline is the most abundant and known to have several adverse effects in humans, specially an increased risk of oral cancer. On evaluating the effects of arecoline on the male endocrine physiology in Wistar rats, it was found that arecoline treatment led to an overall enlargement and increase in the wet weight of the prostate gland, and a two-fold increase in serum gonadotropin and testosterone levels. Since the prostate is a major target for testosterone, the consequences of arecoline consumption were studied specifically in the prostate gland. Arecoline treatment led to an increase in the number of rough endoplasmic reticulum and reduction of secretory vesicles, signifying a hyperactive state of the prostate. Increased expression of androgen receptors in response to arecoline allowed for enhanced effect of testosterone in the prostate of treated animals, which augmented cell proliferation, subsequently confirmed by an increase in the expression of Ki-67 protein. Cellular proliferation was also the outcome of concomitant over expression of the G(1)-to-S cell cycle regulatory proteins, cyclin D1 and CDK4, both at the transcriptional and translational levels. Taken together, the findings provide the first evidence that regular use of arecoline may lead to prostatic hyperplasia and hypertrophy, and eventually to disorders associated with prostate enlargement. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Effects of fractionated radiation on the brain vasculature in a murine model: Blood-brain barrier permeability, astrocyte proliferation, and ultrastructural changes

    SciTech Connect

    Yuan Hong; Gaber, M. Waleed . E-mail: wgaber@utmem.edu; Boyd, Kelli; Wilson, Christy M.; Kiani, Mohammad F.; Merchant, Thomas E.

    2006-11-01

    Purpose: Radiation therapy of CNS tumors damages the blood-brain barrier (BBB) and normal brain tissue. Our aims were to characterize the short- and long-term effects of fractionated radiotherapy (FRT) on cerebral microvasculature in mice and to investigate the mechanism of change in BBB permeability in mice. Methods and Materials: Intravital microscopy and a cranial window technique were used to measure BBB permeability to fluorescein isothiocyanate (FITC)-dextran and leukocyte endothelial interactions before and after cranial irradiation. Daily doses of 2 Gy were delivered 5 days/week (total, 40 Gy). We immunostained the molecules to detect the expression of glial fibrillary acidic protein and to demonstrate astrocyte activity in brain parenchyma. To relate the permeability changes to endothelial ultrastructural changes, we used electron microscopy. Results: Blood-brain barrier permeability did not increase significantly until 90 days after FRT, at which point it increased continuously until 180 days post-FRT. The number of adherent leukocytes did not increase during the study. The number of astrocytes in the cerebral cortex increased significantly; vesicular activity in endothelial cells increased beginning 90 days after irradiation, and most tight junctions stayed intact, although some were shorter and less dense at 120 and 180 days. Conclusions: The cellular and microvasculature response of the brain to FRT is mediated through astrogliosis and ultrastructural changes, accompanied by an increase in BBB permeability. The response to FRT is delayed as compared with single-dose irradiation treatment, and does not involve leukocyte adhesion. However, FRT induces an increase in the BBB permeability, as in the case of single-dose irradiation.

  15. p53, cellular proliferation, and apoptosis-related factors in thymic neuroendocrine tumors.

    PubMed

    Gal, Anthony A; Sheppard, Mary N; Nolen, John D L; Cohen, Cynthia

    2004-01-01

    Thymic neuroendocrine tumors are biologically aggressive neoplasms with extensive local invasion and high mortality. Although various markers of cellular proliferation and apoptosis have correlated with degrees of tumor differentiation in pulmonary neuroendocrine neoplasms, they have not been systematically studied in thymic neuroendocrine tumors. We immunostained 21 cases of thymic neuroendocrine tumors for p53, MIB-1, and the apoptosis-related markers Bcl-2, Bcl-x, and Bax. By histological classification the cases were low-grade (nine cases), intermediate-grade (eight cases), and high-grade (four cases) thymic neuroendocrine tumors. p53 was expressed in five cases: 1/9 low grade, 3/8 intermediate grade, and 2/4 high grade. The mean cellular proliferation (MIB-1) was 7.1% (range 2-12%) in low-grade thymic neuroendocrine tumors, 6.1% (range 2-15%) in intermediate-grade thymic neuroendocrine tumors, and 34.2% (range 2-80%) in high-grade thymic neuroendocrine tumors. Bcl-2 was expressed in 16 cases: 7/9 low grade, 5/8 intermediate grade, and 4/4 high grade. Bcl-x was expressed in 16 cases: 7/9 low grade, 6/8 intermediate grade, and 3/4 high grade. Bax was expressed in 13 cases: 5/9 low grade, 4/8 intermediate grade, and 4/4 high grade. The presence of mutant p53 in the tumor was associated with a statistically significant decreased mean survival (P<0.05). In contrast, either by positive or negative staining or by the score technique (staining intensity x percentage of cells staining), the presence of Bcl-x was associated with an increased mean survival (P<0.05). Finally, a Bcl-x : Bax ratio >or=1 was also associated with an increased mean survival, as compared to a Bcl-x : Bax ratio >or=1 (P<0.05). Our study shows that p53 expression and certain apoptosis markers correlate with survival. The expression of these markers may account for differences in biological behavior.

  16. 9-cis-retinoic Acid and troglitazone impacts cellular adhesion, proliferation, and integrin expression in K562 cells.

    PubMed

    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.

  17. Stochastic cellular automata model of cell migration, proliferation and differentiation: validation with in vitro cultures of muscle satellite cells.

    PubMed

    Garijo, N; Manzano, R; Osta, R; Perez, M A

    2012-12-07

    Cell migration and proliferation has been modelled in the literature as a process similar to diffusion. However, using diffusion models to simulate the proliferation and migration of cells tends to create a homogeneous distribution in the cell density that does not correlate to empirical observations. In fact, the mechanism of cell dispersal is not diffusion. Cells disperse by crawling or proliferation, or are transported in a moving fluid. The use of cellular automata, particle models or cell-based models can overcome this limitation. This paper presents a stochastic cellular automata model to simulate the proliferation, migration and differentiation of cells. These processes are considered as completely stochastic as well as discrete. The model developed was applied to predict the behaviour of in vitro cell cultures performed with adult muscle satellite cells. Moreover, non homogeneous distribution of cells has been observed inside the culture well and, using the above mentioned stochastic cellular automata model, we have been able to predict this heterogeneous cell distribution and compute accurate quantitative results. Differentiation was also incorporated into the computational simulation. The results predicted the myotube formation that typically occurs with adult muscle satellite cells. In conclusion, we have shown how a stochastic cellular automata model can be implemented and is capable of reproducing the in vitro behaviour of adult muscle satellite cells.

  18. LETM1-dependent mitochondrial Ca2+ flux modulates cellular bioenergetics and proliferation

    PubMed Central

    Doonan, Patrick J.; Chandramoorthy, Harish C.; Hoffman, Nicholas E.; Zhang, Xueqian; Cárdenas, César; Shanmughapriya, Santhanam; Rajan, Sudarsan; Vallem, Sandhya; Chen, Xiongwen; Foskett, J. Kevin; Cheung, Joseph Y.; Houser, Steven R.; Madesh, Muniswamy

    2014-01-01

    Dysregulation of mitochondrial Ca2+-dependent bioenergetics has been implicated in various pathophysiological settings, including neurodegeneration and myocardial infarction. Although mitochondrial Ca2+ transport has been characterized, and several molecules, including LETM1, have been identified, the functional role of LETM1-mediated Ca2+ transport remains unresolved. This study examines LETM1-mediated mitochondrial Ca2+ transport and bioenergetics in multiple cell types, including fibroblasts derived from patients with Wolf-Hirschhorn syndrome (WHS). The results show that both mitochondrial Ca2+ influx and efflux rates are impaired in LETM1 knockdown, and similar phenotypes were observed in ΔEF hand, D676A D688KLETM1 mutant-overexpressed cells, and in cells derived from patients with WHS. Although LETM1 levels were lower in WHS-derived fibroblasts, the mitochondrial Ca2+ uniporter components MCU, MCUR1, and MICU1 remain unaltered. In addition, the MCU mitoplast patch-clamp current (IMCU) was largely unaffected in LETM1-knockdown cells. Silencing of LETM1 also impaired basal mitochondrial oxygen consumption, possibly via complex IV inactivation and ATP production. Remarkably, LETM1 knockdown also resulted in increased reactive oxygen species production. Further, LETM1 silencing promoted AMPK activation, autophagy, and cell cycle arrest. Reconstitution of LETM1 or antioxidant overexpression rescued mitochondrial Ca2+ transport and bioenergetics. These findings reveal the role of LETM1-dependent mitochondrial Ca2+ flux in shaping cellular bioenergetics.—Doonan, P J., Chandramoorthy, H. C., Hoffman, N. E., Zhang, X., Cárdenas, C., Shanmughapriya, S., Rajan, S., Vallem, S., Chen, X., Foskett, J. K., Cheung, J. Y., Houser, S. R., Madesh, M. LETM1-dependent mitochondrial Ca2+ flux modulates cellular bioenergetics and proliferation. PMID:25077561

  19. Evaluation of HO-1 expression, cellular ROS production, cellular proliferation and cellular apoptosis in human esophageal squamous cell carcinoma tumors and cell lines.

    PubMed

    Ren, Quan-Guang; Yang, Sheng-Li; Hu, Jian-Li; Li, Pin-Dong; Chen, Ye-Shan; Wang, Qiu-Shuang

    2016-04-01

    Patients with esophageal squamous cell carcinoma (ESCC) have a poor prognosis. However, the related mechanisms are unclear, thus we investigated the expression of HO-1 in ESCC tissue and explored possible mechanisms of tumor progression. Expression of HO-1 was examined by immunohistochemistry in 143 ESCC tumors. The correlation of HO-1 with clinicopathological characteristics was also examined. Two human ESCC cell lines, TE-13 and Eca109 were studied. Silencing of cell line HO-1 by specific small interfering RNA (siRNA) was evaluated using real-time quantitative PCR. Cell line viability, apoptosis and intracellular levels of reactive oxygen species (ROS) after transfection were determined using MTT and flow cytometry, respectively. HO-1, Bax, Bcl-2 and A-caspase-3/-9 expression was evaluated using western blot analyses. We found that HO-1 was expressed in 58 of 143 ESCC tumors, mainly in the cytoplasm. There was a significant association between HO-1 expression and tumor grade (P<0.001). Knockdown of HO-1 expression in cell lines was associated with significantly decreased cellular proliferation (P<0.05) and a higher rate of apoptosis (P<0.001) 48 h after treatment. Treatment of the cell lines with the ROS inhibitor N-acetylcysteine abrogated this effect. Knockdown of HO-1 was associated with increased A-caspase-3 and -9 expression, but no change in Bax or Bcl-2 expression or Bax/Bcl-2 ratio was observed. Thus, the present study identified that ESCC tumors frequently expressed HO-1. Knockdown of HO-1 promoted apoptosis through activation of a ROS-mediated caspase apoptosis pathway.

  20. HDR brachytherapy decreases proliferation rate and cellular progression of a radioresistant human squamous cell carcinoma in vitro.

    PubMed

    Geraldo, Jony M; Scalzo, Sérgio; Reis, Daniela S; Leão, Thiago L; Guatimosim, Silvia; Ladeira, Luiz O; Andrade, Lídia M

    2017-09-01

    To investigate the effects of high dose rate (HDR) brachytherapy on cellular progression of a radioresistant human squamous cell carcinoma in vitro, based on clinical parameters. An acrylic platform was designed to attach tissue culture flasks and assure source positioning during irradiation. At exponential phase, A431cells, a human squamous cell carcinoma, were irradiated twice up to 1100 cGy. Cellular proliferation was assessed by Trypan blue exclusion assay and survival fraction was calculated by clonogenic assay. DNA content analysis and cell cycle phases were assessed by flow cytometry and gel electrophoresis, respectively. Cellular death patterns were measured by HOPI double-staining method. Significant decreasing cellular proliferation rate (p < 0.05) as well as reduced survival fraction (p < 0.001) in irradiated cells were observed. Moreover, increased percentage of cells arrested in the G2/M phase (32.3 ± 1.5%) in the irradiated group as compared with untreated cells (8.22 ± 1.2%) was detected. Also, a significant (p < 0.0001) nuclei shrinking in irradiated cells without evidence of necrosis or apoptosis was found. HDR brachytherapy led to a decreased proliferation rate and cell survival and also hampered cellular progression to mitosis suggesting that tumor cell death mainly occurred due to mitotic death and G2/M cell cycle arrest.

  1. Different effects of estrogen and progesterone on experimental atherosclerosis in female versus male rabbits. Quantification of cellular proliferation by bromodeoxyuridine.

    PubMed

    Hanke, H; Hanke, S; Finking, G; Muhic-Lohrer, A; Mück, A O; Schmahl, F W; Haasis, R; Hombach, V

    1996-07-15

    The aim of the present study was to compare the effect of estrogen and progesterone on the development of experimental atherosclerosis in female versus male rabbits to assess possible sex-specific differences. A total of 32 female and 32 male New Zealand White rabbits were ovariectomized or castrated. In addition to a 0.5% cholesterol diet, the rabbits received estradiol alone (1 mg/kg body wt [BW] per week), progesterone alone (25 mg/kg BW per week), or combined estradiol-progesterone in these dosages during 12 weeks. Ovariectomized female and castrated male rabbits served as control groups without hormone treatment. Before excision of the vessels, bromodeoxyuridine labeling was performed to determine the extent of cellular proliferation in the atherosclerotic lesions. The aortic arch was analyzed immunohistologically and morphometrically. An inhibitory effect of estrogen on intimal plaque size was found in female rabbits compared with the ovariectomized control group (0.7 +/- 0.5 versus 3.7 +/- 2.5 mm2, P < .002; proliferating cells, 3.1 +/- 1.8% versus 8.5 +/- 2.6%, P < .002). In combination with progesterone, however, estrogen was not able to reduce intimal plaque size or cellular proliferation. In contrast, estradiol in castrated male rabbits was not associated with an inhibitory effect on cellular proliferation or intimal thickening compared with controls (estrogen treatment, 7.6 +/- 2.1% proliferating cells and 2.8 +/- 1.0 mm2 neointima; control group, 7.2 +/- 2.1% cellular proliferation and 2.9 +/- 1.2 mm2 intimal thickening). Our data suggest that the atheroprotective effect of estrogen is probably due to a mechanism that is present in female rabbits only.

  2. Low-dose dental irradiation decreases oxidative stress in osteoblastic MC3T3-E1 cells without any changes in cell viability, cellular proliferation and cellular apoptosis.

    PubMed

    Pramojanee, Sakarat N; Pratchayasakul, Wasana; Chattipakorn, Nipon; Chattipakorn, Siriporn C

    2012-03-01

    Cellular responses following low-dose irradiation have been widely debated. Several studies have revealed detrimental effects of low-dose irradiation; however, some studies have shown contrasting results. Moreover, the effects of periapical irradiation on osteoblastic cells have not yet been revealed. Therefore, in this study, we tested the hypothesis that low-dose dental irradiation of osteoblastic cells reduces reactive oxygen species (ROS) production and leads to increased cellular proliferation and high-dose dental irradiation of osteoblastic cells increases ROS production and leads to cellular apoptosis. We irradiated MC3T3-E1 cells with various doses of periapical irradiation (0, 1, 2, 5 and 10 doses, 1.5 mGy/dose). We evaluated cell viability using MTT assay, the expression of Bax and Bcl-2, as markers for apoptosis and the expression of cyclin D1 as a marker for cell proliferation 24h after each irradiation. We also measured ROS production 4h following each irradiation. ROS production was significantly reduced after one dose of periapical irradiation (1.5 mGy); however, after 10 doses (15 mGy), ROS production was significantly increased (p<0.05). None of the doses of dental radiation affected cell viability as determined by MTT assay, nor did they change the apoptotic marker: (the Bax/Bcl-2 ratio). However, 10 doses of dental irradiation significantly decreased the expression of cyclin D1. Our findings suggest that low-dose dental radiation may help to detoxify osteoblastic cells by reducing ROS production without any changes in cell viability, cellular apoptosis or proliferation. However, high-dose dental radiation impairs osteoblastic proliferation via increase ROS production without any changes in cell viability or apoptotic responses. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Loss of FBP function arrests cellular proliferation and extinguishes c-myc expression

    PubMed Central

    He, Liusheng; Liu, Juhong; Collins, Irene; Sanford, Suzanne; O'Connell, Brian; Benham, Craig J.; Levens, David

    2000-01-01

    The c-myc regulatory region includes binding sites for a large set of transcription factors. The present studies demonstrate that in the absence of FBP [far upstream element (FUSE)-binding protein], which binds to the single-stranded FUSE, the remainder of the set fails to sustain endogenous c-myc expression. A dominant-negative FBP DNA-binding domain lacking effector activity or an antisense FBP RNA, expressed via replication-defective adenovirus vectors, arrested cellular proliferation and extinguished native c-myc transcription from the P1 and P2 promoters. The dominant-negative FBP initially augmented the single-stranded character of FUSE; however, once c-myc expression was abolished, melting at FUSE could no longer be supported. In contrast, with antisense FBP RNA, the single-stranded character of FUSE decreased monotonically as the transcription of endogenous c-myc declined. Because transcription is the major source of super-coiling in vivo, we propose that by binding torsionally strained DNA, FBP measures promoter activity directly. We also show that FUSE is predicted to behave as a torsion-regulated switch poised to regulate c-myc and to confer a higher order regulation on a large repertoire of factors. PMID:10698944

  4. [The effects of 1,2-dichloroethane on the cellular proliferation, cellular cycle and apoptosis of SW620 cells in vitro].

    PubMed

    Li, Chen; Zhang, Wei-min; Luo, Ming-jin; Yang, Jun; Wang, Jing

    2012-03-01

    To explore the effects of 1,2-dichloroethane (1,2-DCE) on the cellular proliferation, cellular cycle and apoptosis of SW620 cells in vitro. SW620 cells were exposed to 1,2-DCE at different concentrations for 0.5 and 1 h. MTT assay was used to detect the relative number and relative viability, the low cytometry (FCM) assay was utilized to measure the cell cycle and apoptosis. The results of MTT assay showed that the cellular relative viability decreased with the 1,2-DCE's dose and exposure time. Compared with the DMSO group, the relative cellular viability of cells exposed to 1,2-DCE at the doses of 75, 100, 125, 150, 175, 200 µmol/L for 1 h decreased (P<0.05 or P<0.01). Compared with the groups exposed to 1,2-DCE for 0.5 h, the relative cellular viability of cells exposed to 175 µmol/L 1,2-DCE for 1 h decreased significantly (P<0.01). IC(50) of cellular proliferation in cells exposed to 1,2-DCE for 0.5 h was 89.41 µmol/L, and 95% confidence interval was 85.23 to 93.79 µmol/L. IC(50) of cellular proliferation in cells exposed to 1,2-DCE for 1 h was 87.68 µmol/L, and 95% confidence interval was 83.71 to 91.82 µmol/L. The results of FCM indicated that compared with the control group, the G(0)/G(1) phase in groups exposed to 1,2-DCE at the doses of 25, 50, 100, 150 and 200 µmol/L for 1 h decreased significantly (P<0.05 or P<0.01), the S phase in groups exposed to 1,2-DCE at the doses of 25, 50 and 100 µmol/L for 1 h reduced significantly (P<0.05 or P < 0.01), the G(2)/M phase in groups exposed to 1,2-DCE at the doses of 25, 50, 100, 150 and 200 µmol/L for 1 h increased significantly (P<0.05 or P<0.01). However, 1,2-DCE could not induce apoptosis of SW620 cells. 1,2-DCE could inhibit the proliferation of SW620 cells, and arrest SW620 cells at G(2)/M phase, but could not induce the apoptosis of SW620 cells in vitro.

  5. Brain tryptophan hydroxylase: purification of, production of antibodies to, and cellular and ultrastructural localization in serotonergic neurons of rat midbrain.

    PubMed Central

    Joh, T H; Shikimi, T; Pickel, V M; Reis, D J

    1975-01-01

    Tryptophan hydroxylase [EC 1.14.16.4; L-tryptophan, tetrahydropteridine:oxygen oxidoreductase (5-hydroxylating)], the enzyme catalyzing the rate-limiting step in the biosynthesis of serotonin, was purified 79-fold from the region of the raphe nucleus of rat midbrain by sequential column chromatography and disc-gel electrophoresis. In electrophoresis three bands were distinguished, A, B, and C, which, when separated and submitted individually to electrophoresis, reproduced the same three bands. Bands A and C were enzymatically active and inhibited by para-chlorohenylalanine. Antibodies produced to each of the three bands crossreacted by immuno double diffusion and electrophoresis with each other and homogenates of raphe nuclei; they completely inhibited enzyme activity only of tryptophan hydroxylase. Tryptophan hydroxylase was localized by light and electron immunohistochemistry to serotonin neutrons of the raphe. Ultrastructurally, in cell bodies, the enzyme was distributed in cytoplasm and in association with endoplasmic reticulum and Golgi apparatus. In dendrites and axons, it was associated with microtubules. Tryptophan hydroxylase in brain is only neuronal and cytoplasmic, exists in multiple forms, and is associated with microtubules, suggesting it may be transported from sites of synthesis in cell body into axons. Images PMID:1059145

  6. Cellular Uptake and Ultrastructural Localization Underlie the Pro-apoptotic Activity of a Hydrocarbon-stapled BIM BH3 Peptide.

    PubMed

    Edwards, Amanda L; Wachter, Franziska; Lammert, Margaret; Huhn, Annissa J; Luccarelli, James; Bird, Gregory H; Walensky, Loren D

    2015-09-18

    Hydrocarbon stapling has been applied to restore and stabilize the α-helical structure of bioactive peptides for biochemical, structural, cellular, and in vivo studies. The peptide sequence, in addition to the composition and location of the installed staple, can dramatically influence the properties of stapled peptides. As a result, constructs that appear similar can have distinct functions and utilities. Here, we perform a side-by-side comparison of stapled peptides modeled after the pro-apoptotic BIM BH3 helix to highlight these principles. We confirm that replacing a salt-bridge with an i, i + 4 hydrocarbon staple does not impair target binding affinity and instead can yield a biologically and pharmacologically enhanced α-helical peptide ligand. Importantly, we demonstrate by electron microscopy that the pro-apoptotic activity of a stapled BIM BH3 helix correlates with its capacity to achieve cellular uptake without membrane disruption and accumulate at the organellar site of mechanistic activity.

  7. Early-life environmental intervention may increase the number of neurons, astrocytes, and cellular proliferation in the hippocampus of rats.

    PubMed

    Winkelmann-Duarte, Elisa C; Padilha-Hoffmann, Camila B; Martins, Daniel F; Schuh, Artur F S; Fernandes, Marilda C; Santin, Ricardo; Merlo, Suelen; Sanvitto, Gilberto L; Lucion, Aldo B

    2011-11-01

    Neonatal handling reduces the stress response in adulthood due to a feedback mechanism. The present study analyzed the effects of repeated neonatal environmental intervention (daily handling during the first 10 days after birth) on neuron-, astroglial cell density, and cellular proliferation of the hippocampal (CA1, CA2, and CA3) pyramidal cell layers in female rats. Pups were divided into two groups, nonhandled and handled, which were submitted to repeated handling sessions between postnatal days 1 and 10. Histological and immunohistochemical procedures were used to determine changes in neuron density, astroglial cell density, and cellular proliferation. We found an increase in neuron density in each pyramidal cell layer of the hippocampus (CA1, CA2, and CA3) in female rats (11 and 90 day old) that were handled during the neonatal period. Furthermore, we found an increase in astroglial cell density in both hemispheres of the brain in the handled group. Finally, we observed an increase in cellular proliferation in both hippocampi (CA1, CA2, and CA3) of the brain in female pups (11 days old) handled during the neonatal period. This study demonstrates that an early-life environmental intervention may induce morphological changes in a structure involved with several functions, including the stress response. The results of the current study suggest that neonatal handling may influence the animals' responses to environmental adversities later in life.

  8. Cellular and molecular changes associated with competence acquisition during passion fruit somatic embryogenesis: ultrastructural characterization and analysis of SERK gene expression.

    PubMed

    Rocha, Diego Ismael; Pinto, Daniela Lopes Paim; Vieira, Lorena Melo; Tanaka, Francisco André Ossamu; Dornelas, Marcelo Carnier; Otoni, Wagner Campos

    2016-03-01

    The integration of cellular and molecular data is essential for understanding the mechanisms involved in the acquisition of competence by plant somatic cells and the cytological changes that underlie this process. In the present study, we investigated the dynamics and fate of Passiflora edulis Sims cotyledon explants that were committed to somatic embryogenesis by characterizing the associated ultrastructural events and analysing the expression of a putative P. edulis ortholog of the Somatic Embryogenesis Receptor-like Kinase (SERK) gene. Embryogenic calli were obtained from zygotic embryo explants cultured on Murashige and Skoog medium supplemented with 2,4-dichlorophenoxyacetic acid and 6-benzyladenine. Callus formation was initiated by the division of cells derived from the protodermal and subprotodermal cells on the abaxial side of the cotyledons. The isodiametric protodermal cells of the cotyledon explants adopted a columnar shape and became meristematic at the onset of PeSERK expression, which was not initially detected in explant cells. Therefore, we propose that these changes represent the first observable steps towards the acquisition of a competent state within this regeneration system. PeSERK expression was limited to the early stages of somatic embryogenesis; the expression of this gene was confined to proembryogenic zones and was absent in the embryos after the globular stage. Our data also demonstrated that the dynamics of the mobilization of reserve compounds correlated with the differentiation of the embryogenic callus.

  9. LED illumination effects on proliferation and survival of meningioma cellular cultures

    NASA Astrophysics Data System (ADS)

    Solarte, Efrain; Urrea, Hernan; Criollo, William; Gutierrez, Oscar

    2010-02-01

    Meningioma cell cultures were prepared from frozen cell samples in 96 wells culture plates. Semiconductor light sources (LED) in seven different wavelength ranges were used to illuminate the wells, three different irradiation doses were selected per LED. Control cultures using three different concentrations of FBS were processed for comparison. Cell proliferation, viability, and cytotoxicity were measured every 24 hours for 6 days, using the XTT colorimetric assay (RocheR). None of the irradiated cultures exhibit cytotoxicity; but some of them exhibit proliferation inhibition. The larger proliferation was detected at a 0.05J/cm2 dose, for all LEDs; but for the orange and violet LEDs generated the bigger proliferation rate was measured. Results show the improvement of meningioma cell proliferation using illumination in some given wavelength ranges.

  10. Immunohistochemical characterization of cellular proliferation in small intestinal hyperplasia of rats with hepatic Strobilocercus fasciolaris infection.

    PubMed

    Lagapa, J T; Oku, Y; Kamiya, M

    2008-07-01

    Rats infected with the larvae of Taenia taeniaeformis harbour the intermediate stage of the parasite Strobilocercus fasciolaris within the liver. Affected animals also develop gastric and intestinal hyperplasia. The pathogenesis of the gastric hyperplasia has been extensively investigated, but few studies have addressed the nature of the intestinal changes. This study characterizes the proliferation of small intestinal epithelial cells by immunohistochemical labelling for proliferating cell nuclear antigen (PCNA) and bromodeoxyuridine (BrdU) uptake. At 6 weeks post-infection (wpi) there was an increase in villous length but crypt depth was normal. At 9 wpi there was evidence of epithelial hyperplasia, increased villous length and crypt depth, and expansion of zones of epithelial proliferation. Immunohistochemical labelling indicated that an increase in the number of proliferating cells produced a greater number of progeny cells. Intestinal hyperplasia during experimental infection with T. taeniaeformis larvae is likely to be related to the associated gastropathy, although the mechanisms underlying both changes remain undefined.

  11. Role of cellular bioenergetics in smooth muscle cell proliferation induced by platelet-derived growth factor.

    PubMed

    Perez, Jessica; Hill, Bradford G; Benavides, Gloria A; Dranka, Brian P; Darley-Usmar, Victor M

    2010-05-13

    Abnormal smooth muscle cell proliferation is a hallmark of vascular disease. Although growth factors are known to contribute to cell hyperplasia, the changes in metabolism associated with this response, particularly mitochondrial respiration, remain unclear. Given the increased energy requirements for proliferation, we hypothesized that PDGF (platelet-derived growth factor) would stimulate glycolysis and mitochondrial respiration and that this elevated bioenergetic capacity is required for smooth muscle cell hyperplasia. To test this hypothesis, cell proliferation, glycolytic flux and mitochondrial oxygen consumption were measured after treatment of primary rat aortic VSMCs (vascular smooth muscle cells) with PDGF. PDGF increased basal and maximal rates of glycolytic flux and mitochondrial oxygen consumption; enhancement of these bioenergetic pathways led to a substantial increase in the mitochondrial reserve capacity. Interventions with the PI3K (phosphoinositide 3-kinase) inhibitor LY-294002 or the glycolysis inhibitor 2-deoxy-D-glucose abrogated PDGF-stimulated proliferation and prevented augmentation of glycolysis and mitochondrial reserve capacity. Similarly, when L-glucose was substituted for D-glucose, PDGF-dependent proliferation was abolished, as were changes in glycolysis and mitochondrial respiration. Interestingly, LDH (lactate dehydrogenase) protein levels and activity were significantly increased after PDGF treatment. Moreover, substitution of L-lactate for D-glucose was sufficient to increase mitochondrial reserve capacity and cell proliferation after treatment with PDGF; these effects were inhibited by the LDH inhibitor oxamate. These results suggest that glycolysis, by providing substrates that enhance the mitochondrial reserve capacity, plays an essential role in PDGF-induced cell proliferation, underscoring the integrated metabolic response required for proliferation of VSMCs in the diseased vasculature.

  12. Depolarization of Cellular Resting Membrane Potential Promotes Neonatal Cardiomyocyte Proliferation In Vitro

    PubMed Central

    Lan, Jen-Yu; Williams, Corin; Levin, Michael; Black, Lauren Deems

    2014-01-01

    Cardiomyocytes (CMs) undergo a rapid transition from hyperplastic to hypertrophic growth soon after birth, which is a major challenge to the development of engineered cardiac tissue for pediatric patients. Resting membrane potential (Vmem) has been shown to play an important role in cell differentiation and proliferation during development. We hypothesized that depolarization of neonatal CMs would stimulate or maintain CM proliferation in vitro. To test our hypothesis, we isolated postnatal day 3 neonatal rat CMs and subjected them to sustained depolarization via the addition of potassium gluconate or Ouabain to the culture medium. Cell density and CM percentage measurements demonstrated an increase in mitotic CMs along with a ~2 fold increase in CM numbers with depolarization. In addition, depolarization led to an increase in cells in G2 and S phase, indicating increased proliferation, as measured by flow cytometry. Surprisingly depolarization of Vmem with either treatment led to inhibition of proliferation in cardiac fibroblasts. This effect is abrogated when the study was carried out on postnatal day 7 neonatal CMs, which are less proliferative, indicating that the likely mechanism of depolarization is the maintenance of the proliferating CM population. In summary, our findings suggest that depolarization maintains postnatal CM proliferation and may be a novel approach to encourage growth of engineered tissue and cardiac regeneration in pediatric patients. PMID:25295125

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

    PubMed

    Pascoe, Michaela C; Howells, David W; Crewther, David P; Carey, Leeanne M; Crewther, Sheila G

    2015-01-01

    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.

  14. Comparison of cellular localization of thallium-201, proliferating cell nuclear antigen and Ki-67 in C6 gliomas

    SciTech Connect

    Krishna, L.; Katsetos, C.D.; Vender, J.

    1996-05-01

    In order to substantiate the use of thallium-201 scintigraphy as a tool to evaluate the proliferative capacity of a glioma, we compared the patterns of cellular localization of thallium-201 (Tl-201) with established proliferation markers - proliferating cell nuclear antigen (PCNA) and Ki-67 in C6 gliomas. Six Sprague-Dawley rats were stereotactically implanted with C6 glioma cells intracerebrally. On day 7 post-implantation, 50uCi of Tl-201 chloride were injected intravenously to each animal. The animals were sacrificed 60 minutes post-injection and the brain was immediately removed and frozen in dry ice to preserve cellular integrity. Ten um sections of the C6 glioma were mounted on gelatin coated slides. Consecutive slides were used to perform microautoradiographic localization of Tl-201, as well as immunohistochemical localization of PCNA and Ki-67. Localization of all markers were measured by counting and comparing either silver grain density (for Tl-201), or immunostained cells (for PCNA and Ki-67) in at least 1000 cells in glioma vs normal brain. All three markers localized primarily in the glioma as opposed to normal brain at statistically significant levels at p<0.05. Mean indices for glioma vs non-glioma regions were (i) Tl-201: 142 grains/cm{sup 2} vs 11 grains/cm; (ii) PCNA: 92% vs 4%; (iii) Ki-67: 74% vs 3%. The significant and selective localization of the proliferation markers PCNA and Ki-67 as well as Tl-201 in the glioma cells provides validation at a cellular level, that Tl-201 can be used as a proliferation marker. Existing technology ie. Tl-201 scintigraphy, can be used in the management of biopsy-proven gliomas, to measure the proliferative capacity of the tumor. The advantages of using a non-invasive, relatively inexpensive proliferation marker such as Tl-201 scintigraphy include the capacity to evaluate the proliferation potential of the entire glioma, thereby decreasing the sampling errors inherent in evaluating biopsy specimens.

  15. Enhanced cellular uptake and anti-proliferating effect of chitosan hydrochlorides modified genistein loaded NLC on human lens epithelial cells.

    PubMed

    Zhang, Wenji; Liu, Jinlu; Zhang, Qi; Li, Xuedong; Yu, Shihui; Yang, Xinggang; Kong, Jun; Pan, Weisan

    2014-08-25

    This study was attempted to increase the cellular uptake of developed genistein loaded nanostructured lipid carriers (NLC) into human lens epithelial (HLE) cells by chitosan hydrochlorides coatings when applied in post lens capsule (PCO) treatment, and to provide further understanding of the uptake and anti-proliferation mechanisms inside. NLCs were produced using melt-emulsification method and were subsequently coated with chitosan hydrochlorides by adsorption. The uptake of various particle sizes were evaluated and visualized by confocal laser scanning microscopy (CLSM), showing a size-dependent manner. The uptake of NLC was proved to be endocytosed in an energy dependent and clathrin-mediated endocytosis to HLE cells by the decrease in uptake at lower temperature, when pre-saturated by blank NLC and in the presence of NaN3 and sucrose. CH coating improved the uptake percentage of NLC irrespective of the particle size, without influencing the uptake mechanism. Cell apoptosis was tested using PI and Annexin V-FITC/PI staining, followed by flow cytometer analysis. Higher anti-proliferation effect was observed for CH-NLC in inhibiting the growth of HLE cells by causing more apoptosis. Results above indicate that GEN-NLC surface modified by chitosan hydrochlorides could enhance the trans-cellular performance and anti-proliferating effect as PCO therapy.

  16. Induction of vascular endothelial phenotype and cellular proliferation from human cord blood stem cells cultured in simulated microgravity

    NASA Astrophysics Data System (ADS)

    Chiu, Brian; Z-M Wan, Jim; Abley, Doris; Akabutu, John

    2005-05-01

    Recent studies have demonstrated that stem cells derived from adult hematopoietic tissues are capable of trans-differentiation into non-hematopoietic cells, and that the culture in microgravity ( μg) may modulate the proliferation and differentiation. We investigated the application of μg to human umbilical cord blood stem cells (CBSC) in the induction of vascular endothelial phenotype expression and cellular proliferation. CD34+ mononuclear cells were isolated from waste human umbilical cord blood samples and cultured in simulated μg for 14 days. The cells were seeded in rotary wall vessels (RWV) with or without microcarrier beads (MCB) and vascular endothelial growth factor was added during culture. Controls consisted of culture in 1 G. The cell cultures in RWV were examined by inverted microscopy. Cell counts, endothelial cell and leukocyte markers performed by flow-cytometry and FACS scan were assayed at days 1, 4, 7 and at the termination of the experiments. Culture in RWV revealed significantly increased cellular proliferation with three-dimensional (3D) tissue-like aggregates. At day 4, CD34+ cells cultured in RWV bioreactor without MCB developed vascular tubular assemblies and exhibited endothelial phenotypic markers. These data suggest that CD34+ human umbilical cord blood progenitors are capable of trans-differentiation into vascular endothelial cell phenotype and assemble into 3D tissue structures. Culture of CBSC in simulated μg may be potentially beneficial in the fields of stem cell biology and somatic cell therapy.

  17. Celecoxib pre-treatment in human colorectal adenocarcinoma patients is associated with gene expression alterations suggestive of diminished cellular proliferation.

    PubMed

    Auman, James Todd; Church, Robert; Lee, Soo-Youn; Watson, Mark A; Fleshman, James W; Mcleod, Howard L

    2008-08-01

    Cancer cells treated with the cyclooxygenase-2 inhibitor celecoxib show growth inhibition and induced apoptosis. This study was conducted to determine if the same processes are relevant to celecoxib's effects on human colorectal adenocarcinomas treated in vivo. A cohort of 23 patients with primary colorectal adenocarcinomas was randomised to receive a 7-d course of celecoxib (400mg b.i.d.) or no drug prior to surgical resection. Gene expression profiling was performed on resected adenocarcinomas from the cohort of patients. Using fold change (>1.5) and p-value (<0.05) cut-offs, 190 genes were differentially expressed between adenocarcinomas from patients receiving celecoxib and those that did not. The celecoxib pre-treated samples showed decreased expression levels in multiple genes involved in cellular lipid and glutathione metabolism; changes associated with diminished cellular proliferation. Celecoxib pre-treatment for 7 d in vivo is associated with alterations in colorectal adenocarcinoma gene expression which are suggestive of diminished cellular proliferation.

  18. Celecoxib pre-treatment in human colorectal adenocarcinoma patients is associated with gene expression alterations suggestive of diminished cellular proliferation

    PubMed Central

    Auman, James Todd; Church, Robert; Lee, Soo-Youn; Watson, Mark A.; Fleshman, James W.; Mcleod, Howard L.

    2008-01-01

    Cancer cells treated with the cyclooxygenase-2 inhibitor celecoxib show growth inhibition and induced apoptosis. This study was conducted to determine if the same processes are relevant to celecoxib’s effects on human colorectal adenocarcinomas treated in vivo. A cohort of 23 patients with primary colorectal adenocarcinomas was randomized to receive a 7-day course of celecoxib (400 mg b.i.d.) or no drug prior to surgical resection. Gene expression profiling was performed on resected adenocarcinomas from the cohort of patients. Using fold change (>1.5) and p-value (<0.05) cut-offs, 190 genes were differentially expressed between adenocarcinomas from patients receiving celecoxib and those that did not. The celecoxib pre-treated samples showed decreased expression levels in multiple genes involved in cellular lipid and glutathione metabolism; changes associated with diminished cellular proliferation. Celecoxib pre-treatment for 7 days in vivo is associated with alterations in colorectal adenocarcinoma gene expression which are suggestive of diminished cellular proliferation. PMID:18653328

  19. Feasibility of obtaining breast epithelial cells from healthy women for studies of cellular proliferation.

    PubMed

    Miller, N A; Thomas, M; Martin, L J; Hedley, D W; Michal, S; Boyd, N F

    1997-05-01

    Increased dietary fat intake and rate of breast epithelial cell proliferation have each been associated with the development of breast cancer. The goal of this study was to measure the effect of a low fat, high carbohydrate diet on the rate of breast epithelial cell proliferation in women at high risk for breast cancer. Women were recruited from the intervention and control groups of a randomized low fat dietary intervention trial, breast epithelial cells were obtained by fine needle aspiration, and cell proliferation was assessed in these samples using immunofluorescent detection of Ki-67 and PCNA. The effects of needle size and study group on cell yield and cytologic features of the cells were also examined. Fifty three women (20 in the intervention group and 33 in the control group) underwent the biopsy procedure. Slides from 38 subjects were stained for Ki-67 and from 14 subjects for PCNA. No cell proliferation (fluorescence) was detected for either Ki-67 or PCNA in any of the slides. Epithelial cell yield and number of stromal fragments were greater with a larger needle size. Numbers of stromal fragments and bipolar naked nuclei were greater in the low fat as compared to the control group but no differences in epithelial cell yield were observed between the two groups. This study confirms that fine needle aspiration biopsy is a feasible method of obtaining epithelial cells from women without discrete breast masses, but suggests that cell proliferation cannot be assessed using Ki-67 and PCNA in such samples.

  20. Cellular Retinoic Acid-Binding Protein 1 Modulates Stem Cell Proliferation to Affect Learning and Memory in Male Mice.

    PubMed

    Lin, Yu-Lung; Persaud, Shawna D; Nhieu, Jennifer; Wei, Li-Na

    2017-09-01

    Retinoic acid (RA) is the active ingredient of vitamin A. It exerts its canonical activity by binding to nuclear RA receptors (RARs) to regulate gene expression. Increasingly, RA is also known to elicit nongenomic RAR-independent activities, most widely detected in activating extracellular regulated kinase (ERK)1/2. This study validated the functional role of cellular retinoic acid-binding protein 1 (Crabp1) in mediating nongenomic activity in RA, specifically activating ERK1/2 to rapidly augment the cell cycle by expanding the growth 1 phase and slowing down embryonic stem cell and neural stem cell (NSC) proliferation. The study further uncovered the physiological activity of Crabp1 in modulating NSC proliferation and animal behavior. In the Crabp1 knockout mouse hippocampus, where Crabp1 is otherwise detected in the subgranular zone, neurogenesis and NSC proliferation increased and hippocampus-dependent brain functions such as learning and memory correspondingly improved. This study established the physiological role of Crabp1 in modulating stem cell proliferation and hippocampus-dependent brain activities such as learning and memory. Copyright © 2017 Endocrine Society.

  1. An ultrastructural analysis of cellular death in the CA1 field in the rat hippocampus after transient forebrain ischemia followed by 2, 4 and 10 days of reperfusion.

    PubMed

    Winkelmann, Eliane Roseli; Charcansky, Alexandre; Faccioni-Heuser, M Cristina; Netto, Carlos Alexandre; Achaval, Matilde

    2006-10-01

    An ultrastructural study was performed to investigate the type of cellular death that occurs in hippocampal CA1 field pyramidal neurons after 10 and 20 min of transient cerebral ischemia in the male adult Wistar rats, followed by 2, 4 and 10 days of reperfusion. The four-vessel occlusion method was used to induce ischemic insult for either 10 or 20 min, following which the animals were submitted to either 2, 4 or 10 days of reperfusion. The animals were then anaesthetised, and their brains removed, dehydrated, embedded, sectioned and examined under a transmission electron microscope. After ischemic insult, neurons from the CA1 field presented alterations, corresponding to the initial, intermediate and final stages of the degenerative process. The only difference observed between the 10 and 20 min ischemic groups was the degree of damage; the reaction was stronger in 20 min groups than in the 10 min groups. While neurons were found in the different stages of oncotic necrosis in all groups, differences were found between the groups in relation to prevalent stages. In both ischemic groups, after 2 days of reperfusion, the initial stage of oncotic necrosis was prevalent and large numbers of neurons appeared normal. In both groups, after 4 days of reperfusion, most of the neurons showed more advanced alterations, typical of an intermediate stage. In both groups, after 10 days of reperfusion, alterations corresponding to the intermediate and final stages of oncotic necrosis were also predominant. However, few intact neurons were identified and the neuropile appeared more organised, with numerous glial cells. In summary, the pyramidal neurons of the CA1 field displayed selective vulnerability and exhibited a morphological death pattern corresponding exclusively to an oncotic necrotic pathway.

  2. Evidence that thyroid hormone induces olfactory cellular proliferation in salmon during a sensitive period for imprinting.

    PubMed

    Lema, Sean C; Nevitt, Gabrielle A

    2004-09-01

    Salmon have long been known to imprint and home to natal stream odors, yet the mechanisms driving olfactory imprinting remain obscure. The timing of imprinting is associated with elevations in plasma thyroid hormone levels, with possible effects on growth and proliferation of the peripheral olfactory system. Here, we begin to test this idea by determining whether experimentally elevated plasma levels of 3,5,3'-triiodothyronine (T(3)) influence cell proliferation as detected by the 5-bromo-2'-deoxyuridine (BrdU) cell birth-dating technique in the olfactory epithelium of juvenile coho salmon (Oncorhynchus kisutch). We also explore how natural fluctuations in thyroxine (T(4)) relate to proliferation in the epithelium during the parr-smolt transformation. In both studies, we found that BrdU labeled both single and clusters of mitotic cells. The total number of BrdU-labeled cells in the olfactory epithelium was significantly greater in fish with artificially elevated T(3) compared with placebo controls. This difference in proliferation was restricted to the basal region of the olfactory epithelium, where multipotent progenitor cells differentiate into olfactory receptor neurons. The distributions of mitotic cluster sizes differed significantly from a Poisson distribution for both T(3) and placebo treatments, suggesting that proliferation tends to be non-random. Over the course of the parr-smolt transformation, changes in the density of BrdU cells showed a positive relationship with natural fluctuations in plasma T(4). This relationship suggests that even small changes in thyroid activity can stimulate the proliferation of neural progenitor cells in the salmon epithelium. Taken together, our results establish a link between the thyroid hormone axis and measurable anatomical changes in the peripheral olfactory system.

  3. Epidermal cellular proliferation and differentiation in sexually mature male Salmo salar with androgen levels depressed by oil.

    PubMed

    Burton, D; Burton, M P; Truscott, B; Idler, D R

    1985-07-22

    Sexually mature male Salmo salar exhibit epidermal thickening and an increase in goblet cell concentration during the spawning season. The ventral skin, which is likely to experience most abrasive contact during the spawning period, has the thickest epidermis and the greatest goblet cell concentration. Following exposure to crude oil there is inhibition of cellular proliferation and elongation associated with epidermal thickening, and also inhibition of mucigenesis. Data on the androgen levels in these fish, and data from earlier studies involving treatment with hormones, indicate that oil-related epidermal effects during the spawning period are most likely systemic in origin, probably arising from reduced plasmatic androgen levels.

  4. Enhancing the cellular anti-proliferation activity of pyridazinones as c-met inhibitors using docking analysis.

    PubMed

    Xing, Weiqiang; Ai, Jing; Jin, Shiyu; Shi, Zhangxing; Peng, Xia; Wang, Lang; Ji, Yinchun; Lu, Dong; Liu, Yang; Geng, Meiyu; Hu, Youhong

    2015-05-05

    A series of 2, 6-disubstituted pyridazinone derivatives were evaluated and optimized for their c-Met inhibitory activity in enzyme and cellular assay. An analysis of the SAR results arising from computer modeling analysis of members of the library led to the proposal that in order to obtain optimal inhibitory activity in cellular systems the lipophilic/hydrophilic properties of individual structural fragments in the inhibitors need to match those of corresponding binding pockets in the enzyme. Guided by this proposal, the quinoline-pyridazinone 8a, containing hydrophobic 6-indolyl pyridazinone and quinoline moieties along with a hydrophilic morpholine terminal group, was designed and synthesized. The results of studies with this substance showed that it is a selective c-Met inhibitor with both a high enzyme inhibition IC50 value of 4.2 nM and a high EBC-1 cell proliferation inhibition IC50 value of 17 nM.

  5. Inhalation of chrysotile asbestos induces rapid cellular proliferation in small pulmonary vessels of mice and rats

    SciTech Connect

    McGavran, P.D.; Moore, L.B.; Brody, A.R. )

    1990-03-01

    Asbestos inhalation in mice and rats causes a rapid proliferative response in epithelial and interstitial cells, followed by the development of an interstitial lesion at the first alveolar duct bifurcations where fiber deposition and alveolar macrophage accumulation occur. Here we report that endothelial and smooth muscle cells of arterioles and venules near the bifurcations incorporated significantly increased levels of 3H-TdR 19 to 72 hours after chrysotile exposure. As many as 28% of the vessels had labeled cells 31 hours after exposure. No labeled cells were observed in vessels from sham-exposed or iron-exposed controls. This proliferative response resulted in a doubling of both the number of smooth muscle cells and the thickness of the smooth muscle cell layer, determined by ultrastructural morphometry 1 month after exposure. The fact that a variety of cell types incorporates 3H-TdR so rapidly after asbestos inhalation leads us to speculate that the response involves the release of diffusible growth factors.

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

    PubMed

    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.

  7. Evaluation of Pharmacologic Agents to Suppress Intraocular Cellular Proliferation Following Trauma

    DTIC Science & Technology

    1986-07-01

    Treatment of intraocular proliferation with intravitreal injection of triamcinolone acetonide . Am J Ophthalmol 90:810, 1980. 9. Trese MT, Spitznas M... injected in the fashion for tractional retinal detachment model. The effects of triamcinolone seemed very comparable to dexamethasone with an...PG E 1 Prostaglandin PGE1 was injected in a 2 mg suspension into the vitreous cavity. Prostaglandin is a very unstable compound, and we assume has a

  8. Epithelial Xbp1 Is Required for Cellular Proliferation and Differentiation during Mammary Gland Development

    PubMed Central

    Hasegawa, Daisuke; Calvo, Veronica; Avivar-Valderas, Alvaro; Lade, Abigale; Chou, Hsin-I; Lee, Youngmin A.; Farias, Eduardo F.; Aguirre-Ghiso, Julio A.

    2015-01-01

    Xbp1, a key mediator of the unfolded protein response (UPR), is activated by IRE1α-mediated splicing, which results in a frameshift to encode a protein with transcriptional activity. However, the direct function of Xbp1 in epithelial cells during mammary gland development is unknown. Here we report that the loss of Xbp1 in the mammary epithelium through targeted deletion leads to poor branching morphogenesis, impaired terminal end bud formation, and spontaneous stromal fibrosis during the adult virgin period. Additionally, epithelial Xbp1 deletion induces endoplasmic reticulum (ER) stress in the epithelium and dramatically inhibits epithelial proliferation and differentiation during lactation. The synthesis of milk and its major components, α/β-casein and whey acidic protein (WAP), is significantly reduced due to decreased prolactin receptor (Prlr) and ErbB4 expression in Xbp1-deficient mammary epithelium. Reduction of Prlr and ErbB4 expression and their diminished availability at the cell surface lead to reduced phosphorylated Stat5, an essential regulator of cell proliferation and differentiation during lactation. As a result, lactating mammary glands in these mice produce less milk protein, leading to poor pup growth and postnatal death. These findings suggest that the loss of Xbp1 induces a terminal UPR which blocks proliferation and differentiation during mammary gland development. PMID:25713103

  9. Trans fatty acids affect cellular viability of human intestinal Caco-2 cells and activate peroxisome proliferator-activated receptors.

    PubMed

    Kloetzel, Marianne; Ehlers, Anke; Niemann, Birgit; Buhrke, Thorsten; Lampen, Alfonso

    2013-01-01

    Trans fatty acids (TFA) are hypothesized to have an impact not only on coronary heart diseases but also on the development of colon cancer. To analyze if TFA exhibit cellular and molecular effects which could be involved in colon tumor progression, cells of the human colorectal adenocarcinoma-derived cell line Caco-2 were treated with various TFA isomers differing in the number and position of trans double bonds. The TFA tested in this study did not increase cellular proliferation but displayed growth-inhibitory effects at concentrations higher than 500 μM. In case of the TFA isomer C18:3 t9, t11, t13, an IC50 value of 23 μM was estimated for cytotoxicity indicating a high cytotoxic potential of this compound. In addition to the cytotoxicity studies, the TFA isomers were tested for their ability to activate peroxisome proliferator-activated receptors (PPAR) by taking advantage of a PPAR-dependent reporter gene assay. In contrast to PPARγ that was not activated by the TFA isomers tested in this study, the substances were shown to moderately activate PPARα, and strong activation was observed for PPARδ. The putative impact of TFA on colon cancer development with respect to PPARδ activation is being discussed.

  10. The p44/wdr77-dependent cellular proliferation process during lung development is re-activated in lung cancer

    PubMed Central

    Gu, Zhongping; Zhang, Fahao; Wang, Zhi-Qiang; Ma, Wencai; Davis, Richard E.; Wang, Zhengxin

    2014-01-01

    During lung development, cells proliferate for a defined length of time before they begin to differentiate. Factors that control this proliferative process and how this growth process is related to lung cancer are currently unknown. Here, we found that the WD40-containing protein (p44/wdr77) was expressed in growing epithelial cells at the early stages of lung development. In contrast, p44/wdr77 expression was diminished in fully differentiated epithelial cells in the adult lung. Loss of p44/wdr77 gene expression led to cell growth arrest and differentiation. Re-expression of p44/wdr77 caused terminally differentiated cells to re-enter the cell cycle. Our findings suggest that p44/wdr77 is essential and sufficient for proliferation of lung epithelial cells. P44/Wdr77 was re-expressed in lung cancer, and silencing p44/wdr77 expression strongly inhibited growth of lung adenocarcinoma cells in tissue culture and abolished growth of lung adenocarcinoma tumor xenografts in mice. The growth arrest induced by loss of p44/wdr77 expression was partially through the p21-Rb signaling. Our results suggest that p44/wdr77 controls cellular proliferation during lung development and this growth process is re-activated during lung tumorigenesis. PMID:22665061

  11. Modulation of Estrogen Response Element-Driven Gene Expressions and Cellular Proliferation with Polar Directions by Designer Transcription Regulators

    PubMed Central

    Muyan, Mesut; Güpür, Gizem; Yaşar, Pelin; Ayaz, Gamze; User, Sırma Damla; Kazan, Hasan Hüseyin; Huang, Yanfang

    2015-01-01

    Estrogen receptor α (ERα), as a ligand-dependent transcription factor, mediates 17β-estradiol (E2) effects. ERα is a modular protein containing a DNA binding domain (DBD) and transcription activation domains (AD) located at the amino- and carboxyl-termini. The interaction of the E2-activated ERα dimer with estrogen response elements (EREs) of genes constitutes the initial step in the ERE-dependent signaling pathway necessary for alterations of cellular features. We previously constructed monomeric transcription activators, or monotransactivators, assembled from an engineered ERE-binding module (EBM) using the ERα-DBD and constitutively active ADs from other transcription factors. Monotransactivators modulated cell proliferation by activating and repressing ERE-driven gene expressions that simulate responses observed with E2-ERα. We reasoned here that integration of potent heterologous repression domains (RDs) into EBM could generate monotransrepressors that alter ERE-bearing gene expressions and cellular proliferation in directions opposite to those observed with E2-ERα or monotransactivators. Consistent with this, monotransrepressors suppressed reporter gene expressions that emulate the ERE-dependent signaling pathway. Moreover, a model monotransrepressor regulated DNA synthesis, cell cycle progression and proliferation of recombinant adenovirus infected ER-negative cells through decreasing as well as increasing gene expressions with polar directions compared with E2-ERα or monotransactivator. Our results indicate that an ‘activator’ or a ‘repressor’ possesses both transcription activating/enhancing and repressing/decreasing abilities within a chromatin context. Offering a protein engineering platform to alter signal pathway-specific gene expressions and cell growth, our approach could also be used for the development of tools for epigenetic modifications and for clinical interventions wherein multigenic de-regulations are an issue. PMID:26295471

  12. The effect of ruby laser light on cellular proliferation of epidermal cells.

    PubMed

    Liew, S H; Grobbelaar, A O; Gault, D T; Green, C J; Linge, C

    1999-11-01

    In ruby laser-assisted hair removal, microscopic damage is often seen in the basal epidermal cells, where melanosomes are concentrated. It is not known whether this treatment leads to cellular hyperproliferation. It was the aim of this study to investigate this. Ten white patients were treated with the Chromos 694-nm Depilation Ruby Laser, and biopsies taken before and after treatments to assess the presence of cell hyperproliferation, which normally accompanies epidermal damage, with immunohistochemical staining of keratin 16 and Ki67. No evidence of cell hyperproliferation was seen in all specimens examined after ruby laser irradiation. The authors conclude that despite the possible microscopic damages seen in the basal epidermis after laser hair removal, there is no evidence of cellular hyperproliferation. This is in contrast to ultraviolet-irradiated cell damage, in which increased basal cell turnover is seen.

  13. 14-3-3σ regulates keratinocyte proliferation and differentiation by modulating Yap1 cellular localization

    PubMed Central

    Sambandam, Sumitha A.T.; Kasetti, Ramesh Babu; Xue, Lei; Dean, Douglas C.; Lu, Qingxian; Li, Qiutang

    2015-01-01

    The homozygous repeated epilation (Er/Er) mouse mutant of the gene encoding 14-3-3σ displays an epidermal phenotype characterized by hyperproliferative keratinocytes and undifferentiated epidermis. Heterozygous Er/+ mice develop spontaneous skin tumors and are highly sensitive to tumor-promoting DMBA/TPA induction. The molecular mechanisms underlying 14-3-3σ regulation of epidermal proliferation, differentiation, and tumor formation have not been well elucidated. In the present study, we found that Er/Er keratinocytes failed to sequester Yap1 in the cytoplasm, leading to its nuclear localization during epidermal development in vivo and under differentiation-inducing culture conditions in vitro. In addition, enhanced Yap1 nuclear localization was also evident in DMBA/TPA-induced tumors from Er/+ skin. Furthermore, shRNA knockdown of Yap1 expression in Er/Er keratinocytes inhibited their proliferation, suggesting that YAP1 functions as a downstream effector of 14-3-3σ controlling epidermal proliferation. We then demonstrated that keratinocytes express all seven 14-3-3 protein isoforms, some of which form heterodimers with 14-3-3σ, either full-length WT or the mutant form found in Er/Er mice. However Er 14-3-3σ does not interact with Yap1, as demonstrated by co-immunoprecipitation. We conclude that Er 14-3-3σ disrupts the interaction between 14-3-3 and Yap1, thus fails to block Yap1 nuclear transcriptional function, causing continued progenitor expansion and inhibition of differentiation in Er/Er epidermis. PMID:25668240

  14. PROX1 gene is differentially expressed in oral cancer and reduces cellular proliferation.

    PubMed

    Rodrigues, Maria F S D; de Oliveira Rodini, Camila; de Aquino Xavier, Flávia C; Paiva, Katiúcia B; Severino, Patrícia; Moyses, Raquel A; López, Rossana M; DeCicco, Rafael; Rocha, Lília A; Carvalho, Marcos B; Tajara, Eloiza H; Nunes, Fabio D

    2014-12-01

    Homeobox genes are a family of transcription factors that play a pivotal role in embryogenesis. Prospero homeobox 1 (PROX1) has been shown to function as a tumor suppressor gene or oncogene in various types of cancer, including oral squamous cell carcinoma (OSCC). We have previously identified PROX1 as a downregulated gene in OSCC. The aim of this study is to clarify the underlying mechanism by which PROX1 regulates tumorigenicity of OSCC cells. PROX1 mRNA and protein expression levels were first investigated in 40 samples of OSCC and in nontumor margins. Methylation and amplification analysis was also performed to assess the epigenetic and genetic mechanisms involved in controlling PROX1 expression. OSCC cell line SCC9 was also transfected to stably express the PROX1 gene. Next, SCC9-PROX1-overexpressing cells and controls were subjected to proliferation, differentiation, apoptosis, migration, and invasion assays in vitro. OSCC samples showed reduced PROX1 expression levels compared with nontumor margins. PROX1 amplification was associated with better overall survival. PROX1 overexpression reduces cell proliferation and downregulates cyclin D1. PROX1-overexpressing cells also exhibited reduced CK18 and CK19 expression and transcriptionally altered the expression of WISP3, GATA3, NOTCH1, and E2F1. Our results suggest that PROX1 functions as a tumor suppressor gene in oral carcinogenesis.

  15. Annexin A1 sustains tumor metabolism and cellular proliferation upon stable loss of HIF1A

    PubMed Central

    Grimm, Christina; Lin, Suling J.; Wappler, Jessica; Klinger, Bertram; Blüthgen, Nils; Du Bois, Ilona; Schmeck, Bernd; Lehrach, Hans; de Graauw, Marjo; Goncalves, Emanuel; Saez-Rodriguez, Julio; Tan, Patrick; Grabsch, Heike I.; Prigione, Alessandro; Kempa, Stefan; Cramer, Thorsten

    2016-01-01

    Despite the approval of numerous molecular targeted drugs, long-term antiproliferative efficacy is rarely achieved and therapy resistance remains a central obstacle of cancer care. Combined inhibition of multiple cancer-driving pathways promises to improve antiproliferative efficacy. HIF-1 is a driver of gastric cancer and considered to be an attractive target for therapy. We noted that gastric cancer cells are able to functionally compensate the stable loss of HIF-1α. Via transcriptomics we identified a group of upregulated genes in HIF-1α-deficient cells and hypothesized that these genes confer survival upon HIF-1α loss. Strikingly, simultaneous knock-down of HIF-1α and Annexin A1 (ANXA1), one of the identified genes, resulted in complete cessation of proliferation. Using stable isotope-resolved metabolomics, oxidative and reductive glutamine metabolism was found to be significantly impaired in HIF-1α/ANXA1-deficient cells, potentially explaining the proliferation defect. In summary, we present a conceptually novel application of stable gene inactivation enabling in-depth deconstruction of resistance mechanisms. In theory, this experimental approach is applicable to any cancer-driving gene or pathway and promises to identify various new targets for combination therapies. PMID:26760764

  16. PROX1 Gene is Differentially Expressed in Oral Cancer and Reduces Cellular Proliferation

    PubMed Central

    Rodrigues, Maria F.S.D.; de Oliveira Rodini, Camila; de Aquino Xavier, Flávia C.; Paiva, Katiúcia B.; Severino, Patrícia; Moyses, Raquel A.; López, Rossana M.; DeCicco, Rafael; Rocha, Lília A.; Carvalho, Marcos B.; Tajara, Eloiza H.; Nunes, Fabio D.

    2014-01-01

    Abstract Homeobox genes are a family of transcription factors that play a pivotal role in embryogenesis. Prospero homeobox 1 (PROX1) has been shown to function as a tumor suppressor gene or oncogene in various types of cancer, including oral squamous cell carcinoma (OSCC). We have previously identified PROX1 as a downregulated gene in OSCC. The aim of this study is to clarify the underlying mechanism by which PROX1 regulates tumorigenicity of OSCC cells. PROX1 mRNA and protein expression levels were first investigated in 40 samples of OSCC and in nontumor margins. Methylation and amplification analysis was also performed to assess the epigenetic and genetic mechanisms involved in controlling PROX1 expression. OSCC cell line SCC9 was also transfected to stably express the PROX1 gene. Next, SCC9-PROX1-overexpressing cells and controls were subjected to proliferation, differentiation, apoptosis, migration, and invasion assays in vitro. OSCC samples showed reduced PROX1 expression levels compared with nontumor margins. PROX1 amplification was associated with better overall survival. PROX1 overexpression reduces cell proliferation and downregulates cyclin D1. PROX1-overexpressing cells also exhibited reduced CK18 and CK19 expression and transcriptionally altered the expression of WISP3, GATA3, NOTCH1, and E2F1. Our results suggest that PROX1 functions as a tumor suppressor gene in oral carcinogenesis. PMID:25526434

  17. New melanogenesis and photobiological processes in activation and proliferation of precursor melanocytes after UV-exposure: ultrastructural differentiation of precursor melanocytes from Langerhans cells

    SciTech Connect

    Jimbow, K.; Uesugi, T.

    1982-02-01

    Photobiological processes involving new melanogenesis after exposure to ultraviolet (UV) light were experimentally studied in C57 black adult mice by histochemistry, cytochemistry, and autoradiography. The trunk and the plantar region of the foot, where no functioning melanocytes were present before exposure, were exposed to UV-A for 14 consecutive days. Both regions revealed a basically similar pattern for new melanogenesis which involved an activation of precursor melanocytes. Essentially all of ''indeterminate'' cells appeared to be precursor melanocytes, the fine structure of which could be differentiated even from poorly developed Langerhans cells. New melanogenesis was manifested by 4 stages of cellular and subcellular reactions of these cells as indicated by histochemistry of dihydroxyphenylalanine (dopa) and autoradiography of thymidine incorporation: (a) an initial lag in the activation of precursor melanocytes with development of Golgi cisternae and rough endoplasmic reticulum followed by formation of unmelanized melanosomes (day 0 to 2); (b) synthesis of active tyrosinase accumulated in Golgi cisternae and vesicles with subsequent formation of melanized melanosomes in these cells (day 3 to 5); (c) mitotic proliferation of many of these activated cells, followed by an exponential increase of new melanocytes (day 6 to 7); and (d) melanosome transfer with differentiation of 10 nm filaments and arborization of dendrites, but without any significant change in the melanocyte population (day 8 to 14). The melanosome transfer was, however, not obvious until after 7 days of exposure. The size of newly synthesized melanosomes was similar to that of tail skin where native melanocytes were present before exposure.

  18. Cesium reversibly suppresses HeLa cell proliferation by inhibiting cellular metabolism.

    PubMed

    Kobayashi, Daisuke; Kakinouchi, Kei; Nagae, Tomoki; Nagai, Toshihiko; Shimura, Kiyohito; Hazama, Akihiro

    2017-03-01

    The aim of the present study was to investigate the influence of Cs(+) on cultured human cells. We find that HeLa cell growth is suppressed by the addition of 10 mm CsCl into the culture media. In the Cs(+) -treated cells, the intracellular Cs(+) and K(+) concentrations are increased and decreased, respectively. This leads to a decrease in activity of the glycolytic enzyme pyruvate kinase, which uses K(+) as a cofactor. Cs(+) -treated cells show an intracellular pH shift towards alkalization. Based on these results, CsCl presumably suppresses HeLa cell proliferation by inducing an intracellular cation imbalance that affects cell metabolism. Our findings may have implications for the use of Cs(+) in cancer therapy.

  19. MicroRNA-124 inhibits cellular proliferation and invasion by targeting Ets-1 in breast cancer.

    PubMed

    Li, Wentao; Zang, Wenqiao; Liu, Pei; Wang, Yuanyuan; Du, Yuwen; Chen, Xiaonan; Deng, Meng; Sun, Wencong; Wang, Lei; Zhao, Guoqiang; Zhai, Baoping

    2014-11-01

    MicroRNAs (miRNAs) are small non-coding RNAs that, by targeting certain messenger RNAs (mRNAs) for translational repression or cleavage, can regulate the expression of these genes. In addition, miRNAs may also function as oncogenes and tumor-suppressor genes, as the abnormal expression of miRNAs is associated with various human tumors. However, the effects of the expression of miR-124 in breast cancer remain unclear. The present study was conducted to study the expression of miR-124 in breast cancer, paying particular attention to miR-124's relation to the proliferation, invasion, and apoptosis in breast cancer cell MCF-7 and MDA-MB-231. Real-time quantitative RT-PCR (qRT-PCR) was performed to identify miR-124 that was down-regulated in breast cancer tissues. We also showed E26 transformation specific-1 (Ets-1) and miR-124 expression levels in breast cancer tissues that were associated with lymph node metastases. With transfected synthetic miR-124 agomir into MCF-7 and MDA-MB-231, a significant reduction (P < 0.05) in MCF-7 and MDA-MB-231 cell proliferation and colony forming potential was observed after treatment with miR-124. Apoptosis and migration rates were found to be significantly higher in two breast-derived cell lines transfected with a miR-124 agomir (P < 0.05). Luciferase reporter assay and Western blot were used to verify Ets-1 as a potential major target gene of miR-124, and the result showed that miR-124 can bind to putative binding sites within the Ets-1 mRNA 3' untranslated region (UTR) to reduce its expression. Based on these findings, we propose that miR-124 and Ets-1 may serve as a therapeutic agent in breast cancer.

  20. Amantadine inhibits cellular proliferation and induces the apoptosis of hepatocellular cancer cells in vitro.

    PubMed

    Lan, Zengmei; Chong, Zhaoyang; Liu, Cong; Feng, Danyang; Fang, Dihai; Zang, Weijin; Zhou, Jun

    2015-09-01

    Hepatocellular carcinoma (HCC) is one of the most aggressive malignancies worldwide, and its incidence associated with viral infection has increased in recent years. Amantadine is a tricyclic symmetric amine that can effectively protect against the hepatitis C virus. However, its antitumor properties remain unclear. In the present study, the effects of amantadine on tumor cell viability, cell cycle regulation and apoptosis were investigated. The growth of HepG2 and SMMC‑7721 cells (HCC cell lines) was detected by an MTT assay. Flow cytometry was used to investigate cell cycle regulation and apoptosis. Reverse transcription‑quantitative polymerase chain reaction and western blot analysis were also performed to examine the expression of cell cycle‑ and apoptosis‑related genes and proteins, including cyclin E, cyclin D1, cyclin‑dependent kinase 2 (CDK2), B‑cell lymphoma 2 (Bcl‑2) and Bax. Our results demonstrated that amantadine markedly inhibited the proliferation of HepG2 and SMMC‑7721 cells in a dose‑ and time‑dependent manner and arrested the cell cycle at the G0/G1 phase. The levels of the cell cycle‑related genes and proteins (cyclin D1, cyclin E and CDK2) were reduced by amantadine, and apoptosis was significantly induced. Amantadine treatment also reduced Bcl‑2 and increased the Bax protein and mRNA levels. Additionally, Bcl‑2/Bax ratios were lower in the two HCC cell lines following amantadine treatment. Collectively, these results emphasize the role of amantadine in suppressing proliferation and inducing apoptosis in HCC cells, advocating its use as a novel tumor-suppressive therapeutic candidate.

  1. Subcellular taxonomy: An ultrastructural classification system with diagnostic applications

    SciTech Connect

    McLay, A.L.C.; Toner, P.G.

    1985-01-01

    Contents of this work include: Ultrastructure, Nomenclature, and Disease; Numerical Listing: YX Cellular and Subcellular Structure; Alphabetical Listing; and Appendix: Proposed Revised Listing of M-6 Codes.

  2. Linkage between cellular communications, energy utilization, and proliferation in metastatic neuroendocrine cancers

    PubMed Central

    Ippolito, Joseph E.; Merritt, Matthew E.; Bäckhed, Fredrik; Moulder, Krista L.; Mennerick, Steven; Manchester, Jill K.; Gammon, Seth T.; Piwnica-Worms, David; Gordon, Jeffrey I.

    2006-01-01

    To identify metabolic features that support the aggressive behavior of human neuroendocrine (NE) cancers, we examined metastatic prostate NE tumors and derived prostate NE cancer (PNEC) cell lines from a transgenic mouse model using a combination of magic angle spinning NMR spectroscopy, in silico predictions of biotransformations that observed metabolites may undergo, biochemical tests of these predictions, and electrophysiological/calcium imaging studies. Malignant NE cells undergo excitation and increased proliferation when their GABAA, glutamate, and/or glycine receptors are stimulated, use glutamate and GABA as substrates for NADH biosynthesis, and produce propylene glycol, a precursor of pyruvate derived from glycine that increases levels of circulating free fatty acids through extra-NE cell effects. Treatment of nude mice containing PNEC tumor xenografts with (i) amiloride, a diuretic that inhibits Abp1, an enzyme involved in NE cell GABA metabolism, (ii) carbidopa, an inhibitor of dopa decarboxylase which functions upstream of Abp1, plus (iii) flumazenil, a benzodiazepine antagonist that binds to GABAA receptors, leads to significant reductions in tumor growth. These findings may be generally applicable: GeneChip data sets from 471 human neoplasms revealed that components of GABA metabolic pathways, including ABP1, exhibit statistically significant increases in their expression in NE and non-NE cancers. PMID:16895983

  3. Dietary calcium does not reduce experimental colorectal carcinogenesis after small bowel resection despite reducing cellular proliferation.

    PubMed Central

    Barsoum, G H; Thompson, H; Neoptolemos, J P; Keighley, M R

    1992-01-01

    It has been proposed that colorectal carcinogenesis is accompanied by increased mucosal cell proliferation and that the converse may also apply. To examine this thesis, the crypt cell production rate (CCPR) was measured in eight groups of rats (n = 187) that had received 1,2 dimethylhydrazine, 70% small bowel resection, supplemental dietary calcium, or a combination of these. Analysis of variance showed the following: (1) the CCPR decreased between the ileum and distal colon; (2) the CCPR decreased between 16 and 32 weeks; (3) 1,2 dimethylhydrazine and small bowel resection increased the CCPR and calcium decreased the CCPR independently of one another; (4) the CCPR interacted with 1,2 dimethylhydrazine x small bowel resection, calcium x 1,2 dimethylhydrazine and interacted between the site of bowel and calcium, 1,2 dimethylhydrazine, small bowel resection, and 1,2 dimethylhydrazine x small bowel resection (p = 0.014 to p < 0.001). The tumour yield was reduced by calcium in 1,2 dimethylhydrazine treated animals (chi 2 = 14.1, df = 3, p < 0.01) but was unaffected by calcium in 1,2 dimethylhydrazine and small bowel resection treated animals despite significant differences in the CCPR. An increase of the CCPR both preceded and accompanied colorectal carcinogenesis but reduction of the CCPR was not invariably accompanied by reduced carcinogenes. PMID:1452077

  4. In Vivo Analysis of Importin α Proteins Reveals Cellular Proliferation Inhibition and Substrate Specificity

    PubMed Central

    Quensel, Christina; Friedrich, Beate; Sommer, Thomas; Hartmann, Enno; Kohler, Matthias

    2004-01-01

    The “classical” nuclear import pathway depends on importins α and β. Humans have only one importin β, while six α importins have been described. Whether or not distinct α importins are essential for specific import pathways in living human cells is unclear. We used RNA interference technology to specifically down-regulate the expression of ubiquitously expressed human α importins in HeLa cells. Down-regulation of importins α3, α5, α7, and β strongly inhibited HeLa cell proliferation, while down-regulation of importins α1 and α4 had only a minor effect or no effect. Nucleoplasmin import was not prevented by down-regulation of any α importin, indicating that the importin α/β pathway was generally not affected. In contrast, importin α3 or α5 down-regulation specifically inhibited the nuclear import of the Ran guanine nucleotide exchange factor, RCC1. Coinjection of recombinant α importins and RCC1 into down-regulated cells demonstrated that these transport defects were specifically caused by the limited availability of importin α3 in both cases. Thus, importin α3 is the only α importin responsible for the classical nuclear import of RCC1 in living cells. PMID:15542834

  5. B-Myb protein in cellular proliferation, transcription control, and cancer: latest developments.

    PubMed

    Sala, A; Watson, R

    1999-06-01

    Since its isolation exactly a decade ago, B-Myb has intrigued a growing number of scientists interested in understanding the mechanisms of cell proliferation. In many aspects the B-Myb story resembles that of a fashionable transcription factor involved in cell cycle control: E2F-1. Similar to E2F-1, B-Myb is a transcription factor whose expression is regulated at the G1/S border of the cell cycle. Given the ubiquitous expression of B-Myb within different cell types, its link with the cell cycle, and augmented expression in transformed cells, studies are in progress to define the potential role of B-Myb in human cancer. The purpose of this review is not to provide an extensive background to the B-Myb field but rather to describe the latest developments. A comprehensive outline of B-Myb structure and function can be found in the review by Saville and Watson (1998a, Adv. Cancer Res., 72:109-140).

  6. Sphingolipid metabolism is a crucial determinant of cellular fate in nonstimulated proliferating Madin-Darby canine kidney (MDCK) cells.

    PubMed

    Nieto, Francisco Leocata; Pescio, Lucila G; Favale, Nicolás O; Adamo, Ana M; Sterin-Speziale, Norma B

    2008-09-12

    The present report was addressed to study the influence of sphingolipid metabolism in determining cellular fate. In nonstimulated proliferating Madin-Darby canine kidney (MDCK) cells, sphingolipid de novo synthesis is branched mainly to a production of sphingomyelin and ceramide, with a minor production of sphingosylphosphocholine, ceramide 1-phosphate, and sphingosine 1-phosphate. Experiments with (32)P as a radioactive precursor showed that sphingosine 1-phosphate is produced mainly by a de novo independent pathway. Enzymatic inhibition of the de novo pathway and ceramide synthesis affected cell number and viability only slightly, without changing sphingosine 1-phosphate production. By contrast, inhibition of sphingosine kinase-1 activity provoked a significant reduction in both cell number and viability in a dose-dependent manner. When sphingolipid metabolism was studied, an increase in de novo formed ceramide was found, which correlated with the concentration of enzyme inhibitor and the reduction in cell number and viability. Knockdown of sphingosine kinase-1 expression also induced an accumulation of de novo synthesized ceramide, provoking a slight reduction in cell number and viability similar to that induced by a low concentration of the sphingosine kinase inhibitor. Taken together, our results indicate that the level of de novo formed ceramide is controlled by the synthesis of sphingosine 1-phosphate, which appears to occur through a de novo synthesis-independent pathway, most probably the salvage pathway, that is responsible for the MDCK cell fate, suggesting that under proliferating conditions, a dynamic interplay exists between the de novo synthesis and the salvage pathway.

  7. Cellular proliferation and infiltration following interstitial irradiation of normal dog brain is altered by an inhibitor of polyamine synthesis

    SciTech Connect

    Fike, J.R.; Gobbel, G.T.; Chou, D.

    1995-07-15

    The objectives of this study were to quantitatively define proliferative and infiltrative cell responses after focal {sup 125}I irradiation of normal brain, and to determine the effects of an intravenous infusion of {alpha}-defluoromethylornithine (DFMO) on those responses. Adult beagle dogs were irradiated using high activity {sup 125}I sources. Cellular responses were quantified using a histomorphometric analysis. After radiation alone, cellular events included a substantial acute inflammatory response followed by increased BrdU labeling and progressive increases in numbers of capillaries and astrocytes. {alpha}-Difluoromethylornithine treatment significantly affected the measured cell responses. As in controls, an early inflammatory response was measured, but after 2 weeks there were more PMNs/unit area than in controls. The onset of measurable BrdU labeling was delayed in DFMO-treated animals, and the magnitude of labeling was significantly reduced. Increases in astrocyte and vessel numbers/mm{sup 2} were observed after a 2-week delay. At the site of implant, astrocytes from DFMO-treated dogs were significantly smaller than those from controls. There is substantial cell proliferation and infiltration in response to interstitial irradiation of normal brain, and these responses are significantly altered by DFMO treatment. Although the precise mechanisms by which DFMO exerts its effects in this model are not known, the results from this study suggest that modification of radiation injury may be possible by manipulating the response of normal cells to injury. 57 refs., 6 figs.

  8. Cellular and molecular phenotypes of proliferating stromal cells from human carcinomas

    PubMed Central

    Kopantzev, E P; Vayshlya, N A; Kopantseva, M R; Egorov, V I; Pikunov, M; Zinovyeva, M V; Vinogradova, T V; Zborovskaya, I B; Sverdlov, E D

    2010-01-01

    Background: Stromal cells are a functionally important component of human carcinomas. The aim of this study was to obtain and characterise primary cultures of stromal cells from human carcinomas and the corresponding surrounding normal tissue. Methods: Primary stromal cell cultures from tumours of lung, oesophagus and pancreas were obtained using a mild tissue dissociation method and a medium for culturing mesenchymal cells. Immunofluorescence staining and western blotting were used to analyse the expression of differentiation markers and selected known oncoproteins in the cell cultures obtained. Results: A panel of stromal primary cultures was prepared from different human tumours and from matched normal cancer-free tissues. The in vitro proliferative potential of tumour-associated fibroblasts was shown to be higher than that of matched normal stromal cells. A mutational analysis of the TP53 and KRAS2 genes in a number of stromal cultures did not reveal known mutations in most cells of the cultures studied. Western blot analysis showed that stromal cells of lung tumours were characterised by a statistically significantly lower expression level of the p16 protein as compared with that in normal lung stromal cells. An important finding of our study was that, according to immunofluorescence assay, a fraction of fibroblast-like vimentin-positive cells in some tumour and normal stromal cell cultures expressed an epithelial marker – cytokeratins. Conclusions: Proliferating stromal cells from the carcinomas studied proved to be genetically normal cells with altered expression profiles of some genes involved in carcinogenesis, as compared with normal stromal cells. Epithelial-mesenchymal transition may lead to the emergence of transdifferentiated fibroblast-like cells in tumour stroma and in the tumour-surrounding tissue. PMID:20407446

  9. Multifaceted roles of peroxisome proliferator-activated receptors (PPARs) at the cellular and whole organism levels.

    PubMed

    Yessoufou, A; Wahli, W

    2010-09-15

    Chronic disorders, such as obesity, diabetes, inflammation, non-alcoholic fatty liver disease and atherosclerosis, are related to alterations in lipid and glucose metabolism, in which peroxisome proliferator-activated receptors (PPAR)α, PPARβ/δ and PPARγ are involved. These receptors form a subgroup of ligand-activated transcription factors that belong to the nuclear hormone receptor family. This review discusses a selection of novel PPAR functions identified during the last few years. The PPARs regulate processes that are essential for the maintenance of pregnancy and embryonic development. Newly found hepatic functions of PPARα are the mediation of female-specific gene repression and the protection of the liver from oestrogen induced toxicity. PPARα also controls lipid catabolism and is the target of hypolipidaemic drugs, whereas PPARγ controls adipocyte differentiation and regulates lipid storage; it is the target for the insulin sensitising thiazolidinediones used to treat type 2 diabetes. Activation of PPARβ/δ increases lipid catabolism in skeletal muscle, the heart and adipose tissue. In addition, PPARβ/δ ligands prevent weight gain and suppress macrophage derived inflammation. In fact, therapeutic benefits of PPAR ligands have been confirmed in inflammatory and autoimmune diseases, such as encephalomyelitis and inflammatory bowel disease. Furthermore, PPARs promote skin wound repair. PPARα favours skin healing during the inflammatory phase that follows injury, whilst PPARβ/δ enhances keratinocyte survival and migration. Due to their collective functions in skin, PPARs represent a major research target for our understanding of many skin diseases. Taken altogether, these functions suggest that PPARs serve as physiological sensors in different stress situations and remain valuable targets for innovative therapies.

  10. Somatic polyploidization and cellular proliferation drive body size evolution in nematodes

    PubMed Central

    Flemming, Anthony J.; Shen, Zai-Zhong; Cunha, Ana; Emmons, Scott W.; Leroi, Armand M.

    2000-01-01

    Most of the hypodermis of a rhabditid nematode such as Caenorhabditis elegans is a single syncytium. The size of this syncytium (as measured by body size) has evolved repeatedly in the rhabditid nematodes. Two cellular mechanisms are important in the evolution of body size: changes in the numbers of cells that fuse with the syncytium, and the extent of its acellular growth. Thus nematodes differ from mammals and other invertebrates in which body size evolution is caused by changes in cell number alone. The evolution of acellular syncytial growth in nematodes is also associated with changes in the ploidy of hypodermal nuclei. These nuclei are polyploid as a consequence of iterative rounds of endoreduplication, and this endocycle has evolved repeatedly. The association between acellular growth and endoreduplication is also seen in C. elegans mutations that interrupt transforming growth factor-β signaling and that result in dwarfism and deficiencies in hypodermal ploidy. The transforming growth factor-β pathway is a candidate for being involved in nematode body size evolution. PMID:10805788

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

    PubMed

    Feilotter, Harriet E; Michel, Claire; Uy, Paolo; Bathurst, Lauren; Davey, Scott

    2014-01-01

    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.

  12. Fisetin inhibits cellular proliferation and induces mitochondria-dependent apoptosis in human gastric cancer cells.

    PubMed

    Sabarwal, Akash; Agarwal, Rajesh; Singh, Rana P

    2017-02-01

    The anticancer effects of fisetin, a dietary agent, are largely unknown against human gastric cancer. Herein, we investigated the mechanisms of fisetin-induced inhibition of growth and survival of human gastric carcinoma AGS and SNU-1 cells. Fisetin (25-100 μM) caused significant decrease in the levels of G1 phase cyclins and CDKs, and increased the levels of p53 and its S15 phosphorylation in gastric cancer cells. We also observed that growth suppression and death of non-neoplastic human intestinal FHs74int cells were minimally affected by fisetin. Fisetin strongly increased apoptotic cells and showed mitochondrial membrane depolarization in gastric cancer cells. DNA damage was observed as early as 3 h after fisetin treatment which was accompanied with gamma-H2A.X(S139) phosphorylation and cleavage of PARP. Fisetin-induced apoptosis was observed to be independent of p53. DCFDA and MitoSOX analyses showed an increase in mitochondrial ROS generation in time- and dose-dependent fashion. It also increased cellular nitrite and superoxide generation. Pre-treatment with N-acetyl cysteine (NAC) inhibited ROS generation and also caused protection from fisetin-induced DNA damage. The formation of comets were observed in only fisetin treated cells which was blocked by NAC pre-treatment. Further investigation of the source of ROS, using mitochondrial respiratory chain (MRC) complex inhibitors, suggested that fisetin caused ROS generation specifically through complex I. Collectively, these results for the first time demonstrated that fisetin possesses anticancer potential through ROS production most likely via MRC complex I leading to apoptosis in human gastric carcinoma cells. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  13. Tendon's ultrastructure.

    PubMed

    Tresoldi, Ilaria; Oliva, Francesco; Benvenuto, Monica; Fantini, Massimo; Masuelli, Laura; Bei, Roberto; Modesti, Andrea

    2013-01-01

    The structure of a tendon is an important example of complexity of ECM three-dimensional organization. The extracellular matrix (ECM) is a macromolecular network with both structural and regulatory functions. ECM components belong to four major types of macromolecules: the collagens, elastin, proteoglycans, and noncollagenous glycoproteins. Tendons are made by a fibrous, compact connective tissue that connect muscle to bone designed to transmit forces and withstand tension during muscle contraction. Here we show the ultrastructural features of tendon's components.

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

    SciTech Connect

    Sweeny, Larissa; Liu, Zhiyong; Bush, Benjamin D.; Hartman, Yolanda; Zhou, Tong; Rosenthal, Eben L.

    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.

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

    SciTech Connect

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

    1986-05-01

    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/sub 3/ at the end of which time cells were labeled with (/sup 3/H)thymidine, (/sup 3/H)uridine, (/sup 14/C)lysine and (/sup 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.

  16. Ultrastructural changes to rat hippocampus in pentylenetetrazol- and kainic acid-induced status epilepticus: A study using electron microscopy.

    PubMed

    Zhvania, Mzia G; Ksovreli, Mariam; Japaridze, Nadezhda J; Lordkipanidze, Tamar G

    2015-07-01

    A pentylenetetrazol (PTZ)-induced status epilepticus model in rats was used in the study. The brains were studied one month after treatment. Ultrastructural observations using electron microscopy performed on the neurons, glial cells, and synapses, in the hippocampal CA1 region of epileptic brains, demonstrated the following major changes over normal control brain tissue. (i) There is ultrastructural alterations in some neurons, glial cells and synapses in the hippocampal CA1 region. (ii) The destruction of cellular organelles and peripheral, partial or even total chromatolysis in some pyramidal cells and in interneurons are observed. Several astrocytes are proliferated or activated. Presynaptic terminals with granular vesicles and degenerated presynaptic profiles are rarely observed. (iii) The alterations observed are found to be dependent on the frequency of seizure activities following the PTZ treatment. It was observed that if seizure episodes are frequent and severe, the ultrastructure of hippocampal area is significantly changed. Interestingly, the ultrastructure of CA1 area is found to be only moderately altered if seizure episodes following the status epilepticus are rare and more superficial; (iv) alterations in mitochondria and dendrites are among the most common ultrastructural changes seen, suggesting cell stress and changes to cellular metabolism. These morphological changes, observed in brain neurons in status epilepticus, are a reflection of epileptic pathophysiology. Further studies at the chemical and molecular level of neurotransmitter release, such as at the level of porosomes (secretory portals) at the presynaptic membrane, will further reveal molecular details of these changes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Combined carbonate carbon isotopic and cellular ultrastructural studies of individual benthic foraminifera: 2. Toward an understanding of apparent disequilibrium in hydrocarbon seeps

    NASA Astrophysics Data System (ADS)

    Bernhard, Joan M.; Martin, Jonathan B.; Rathburn, Anthony E.

    2010-10-01

    Numerous previous studies show disequilibrium between stable carbon isotope ratios of foraminiferal calcite and pore water dissolved inorganic carbon in hydrocarbon seeps, calling into question the utility of this widely used paleoceanographic tracer as a proxy. We use a recently developed method to compare stable carbon isotope ratios of foraminiferal carbonate with cell ultrastructural observations from individual benthic foraminifera from seep (under chemosynthetic bivalves) and nonseep habitats in Monterey Bay, California, to better understand control(s) of benthic foraminiferal carbon isotope ratios. Two attributes previously proposed to cause the isotopic offsets are diet and symbionts. Ultrastructural analysis shows that positive staining with Rose Bengal indicates presence of foraminiferal cytoplasm, bacterial biomass, or a combination of both and, thus, is not an unequivocal indicator of viability. We also show for the first time that some living seep foraminifera have endobionts. Results from our unique, yet limited, data set are consistent with suggestions that, in our sites, several foraminiferal species collected from seep clam beds may not survive there, diet and symbiont presence do not appear to be major contributors to disequilibrium, little calcification of seep-tolerant foraminiferal species occurs while seep conditions prevail, and microscale variability in habitats could influence δ13C of benthic foraminiferal carbonate. Results further suggest that our knowledge of benthic foraminiferal ecology and biomineralization, especially in extreme habitats such as seeps, must be bolstered before we fully understand the fidelity of paleoenvironmental records derived from benthic foraminiferal test δ13C data.

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

    PubMed Central

    de Oliveira, Simone Santiago Carvalho; 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; dos Santos, André Luis Souza; Branquinha, Marta Helena

    2016-01-01

    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. PMID:27925020

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

    PubMed

    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.

  20. Oligodendroglial cell proliferation arising in an ovarian mature cystic teratoma. Clinicopathological, inmunohistochemical, and ultrastructural study of a case that may represent an oligodendroglioma.

    PubMed

    Serrano-Arévalo, Mónica Lizzette; Lino-Silva, Leonardo Saúl; Domínguez Malagón, Hugo Ricardo

    2017-01-01

    Ovarian mature cystic teratoma (OMCT) is an ovarian benign neoplasm with excellent prognosis presenting components of the three germinal layers. However, transformation into a malignant neoplasm is a rare event (so-called somatic transformation). In most of the cases, the malignant component expresses as epidermoid carcinoma, but occasionally central nervous system tumors occur. Some of the previously reported tumors are astrocytoma, glioblastoma, and ependymoma. Somatic transformation of OMCT into an oligodendroglioma is exceptional. We report a 19-year-old female with a left OMCT with an area of oligonedroglial cells proliferation characterized by immunohistochemical studies with positivity for GFAP and S100, with a low Ki67 index (5%). Additionally, electron microscopy revealed oligodendrocytes with parallel bundles of cytoplasmic intermediate filaments, confirming the oligodendroglial nature of the proliferation. The patient was treated only with left oophorectomy, and three and half years after surgery, there is no evidence of disease.

  1. Girdin/GIV is upregulated by cyclic tension, propagates mechanical signal transduction, and is required for the cellular proliferation and migration of MG-63 cells

    SciTech Connect

    Hu, Jiang-Tian; Li, Yan; Yu, Bing; Gao, Guo-Jie; Zhou, Ting; Li, Song

    2015-08-21

    To explore how Girdin/GIV is regulated by cyclic tension and propagates downstream signals to affect cell proliferation and migration. Human osteoblast-like MG-63 cells were exposed to cyclic tension force at 4000 μstrain and 0.5 Hz for 6 h, produced by a four-point bending system. Cyclic tension force upregulated Girdin and Akt expression and phosphorylation in cultured MG-63 cells. Girdin and Akt each promoted the phosphorylation of the other under stimulated tension. In vitro MTT and transwell assays showed that Girdin and Akt are required for cell proliferation and migration during cellular quiescence. Moreover, STAT3 was determined to be essential for Girdin expression under stimulated tension force in the physiological condition, as well as for osteoblast proliferation and migration during quiescence. These findings suggest that the STAT3/Girdin/Akt pathway activates in osteoblasts in response to mechanical stimulation and may play a significant role in triggering osteoblast proliferation and migration during orthodontic treatment. - Highlights: • Tension force upregulates Girdin and Akt expression and phosphorylation. • Girdin and Akt promotes the phosphorylation of each other under tension stimulation. • Girdin and Akt are required for MG-63 cell proliferation and migration. • STAT3 is essential for Girdin expression after application of the tension forces.

  2. Colloidal Vesicular System of Inositol Hexaphosphate to Counteract DMBA Induced Dysregulation of Markers Pertaining to Cellular Proliferation/Differentiation and Inflammation of Epidermal Layer in Mouse Model.

    PubMed

    Arya, Malti; Tiwari, Prakash; Tripathi, Chandra Bhushan; Parashar, Poonam; Singh, Mahendra; Sinha, Priyam; Yadav, Narayan P; Kaithwas, Gaurav; Gupta, Krishna P; Saraf, Shubhini A

    2017-03-06

    Cancer is a global health problem and chemoprevention is a promising approach for reducing cancer burden. Inositol hexaphosphate (IP6), a natural bioactive constituent of cereals, legumes, etc., has momentous potential as an antiangiogenic agent, that specifically affects malignant cells. The shortcoming is its quick absorption on oral/topical administration. Niosomes are flexible carriers for topical drug delivery. The central venture of current research was to optimize and characterize niosomal delivery system of IP6 for treatment of skin cancer. Thin film hydration method was utilized to prepare IP6 niosomes, and these were dispersed as a suspension in a suitable base. Developed formulations were analyzed for various physicochemical and pharmacological parameters such as particle size, encapsulation efficiency, morphology, drug release, texture analysis, irritability, cell line studies, Western blotting, RT-PCR, and histopathology. IP6 niosomal suspension and IP6 in acetone displayed IC50 value at the concentration of 0.96 mM (0.63 mg/mL) and 1.39 mM (0.92 mg/mL), respectively. IP6 niosomal suspension showed significantly higher (p < 0.05) activity and showed cytotoxic effect in SK-MEL-2 cancer cell line. Crucial events of cellular proliferation and differentiation, like expression of ornithine decarboxylase (ODC), proliferating cell nuclear antigen (PCNA), cycloxygenase-2 (COX-2) and Cyclin D1 were initiated from the fourth hour through application of 7,12-dimethylbenzanthracene (DMBA) on albino mice. The DMBA altered expression of aforesaid enzymes was significantly (P < 0.001) prevented by concomitant application of niosomal formulations. Results of cell line study, Western blotting, RT-PCR, and histopathology suggested that IP6 niosomal suspension could constitute a promising approach for prevention of cellular proliferation as well as DMBA induced dysregulation of cellular proliferation/differentiation and inflammation.

  3. Relationship between peroxisome proliferator-activated receptor alpha activity and cellular concentration of 14 perfluoroalkyl substances in HepG2 cells.

    PubMed

    Rosenmai, Anna Kjerstine; Ahrens, Lutz; le Godec, Théo; Lundqvist, Johan; Oskarsson, Agneta

    2017-08-31

    Peroxisome proliferator-activated receptor alpha (PPARα) is a molecular target for perfluoroalkyl substances (PFASs). Little is known about the cellular uptake of PFASs and how it affects the PPARα activity. We investigated the relationship between PPARα activity and cellular concentration in HepG2 cells of 14 PFASs, including perfluoroalkyl carboxylates (PFCAs), perfluoroalkyl sulfonates and perfluorooctane sulfonamide (FOSA). Cellular concentrations were determined by high-performance liquid chromatography-tandem mass spectrometry and PPARα activity was determined in transiently transfected cells by reporter gene assay. Cellular uptake of the PFASs was low (0.04-4.1%) with absolute cellular concentrations in the range 4-2500 ng mg(-1) protein. Cellular concentration of PFCAs increased with perfluorocarbon chain length up to perfluorododecanoate. PPARα activity of PFCAs increased with chain length up to perfluorooctanoate. The maximum induction of PPARα activity was similar for short-chain (perfluorobutanoate and perfluoropentanoate) and long-chain PFCAs (perfluorododecanoate and perfluorotetradecanoate) (approximately twofold). However, PPARα activities were induced at lower cellular concentrations for the short-chain homologs compared to the long-chain homologs. Perfluorohexanoate, perfluoroheptanoate, perfluorooctanoate, perfluorononanoate (PFNA) and perfluorodecanoate induced PPARα activities >2.5-fold compared to controls. The concentration-response relationships were positive for all the tested compounds, except perfluorooctane sulfonate PFOS and FOSA, and were compound-specific, as demonstrated by differences in the estimated slopes. The relationships were steeper for PFCAs with chain lengths up to and including PFNA than for the other studied PFASs. To our knowledge, this is the first report establishing relationships between PPARα activity and cellular concentration of a broad range of PFASs. Copyright © 2017 John Wiley & Sons, Ltd.

  4. The human ubiquitin-conjugating enzyme Cdc34 controls cellular proliferation through regulation of p27{sup Kip1} protein levels

    SciTech Connect

    Butz, Nicole; Ruetz, Stephan; Natt, Francois; Hall, Jonathan; Weiler, Jan; Mestan, Juergen; Ducarre, Monique; Grossenbacher, Rita; Hauser, Patrick; Kempf, Dominique; Hofmann, Francesco . E-mail: francesco.hofmann@pharma.novartis.com

    2005-02-15

    Ubiquitin-mediated degradation of the cyclin-dependent kinase inhibitor p27{sup Kip1} was shown to be required for the activation of key cyclin-dependent kinases, thereby triggering the onset of DNA replication and cell cycle progression. Although the SCF{sup Skp2} ubiquitin ligase has been reported to mediate p27{sup Kip1} degradation, the nature of the human ubiquitin-conjugating enzyme involved in this process has not yet been determined at the cellular level. Here, we show that antisense oligonucleotides targeting the human ubiquitin-conjugating enzyme Cdc34 downregulate its expression, inhibit the degradation of p27{sup Kip1}, and prevent cellular proliferation. Elevation of p27{sup Kip1} protein level is found to be the sole requirement for the inhibition of cellular proliferation induced upon downregulation of Cdc34. Indeed, reducing the expression of p27{sup Kip1} with a specific antisense oligonucleotide is sufficient to reverse the anti-proliferative phenotype elicited by the Cdc34 antisense. Furthermore, downregulation of Cdc34 is found to specifically increase the abundance of the SCF{sup Skp2} ubiquitin ligase substrate p27{sup Kip1}, but has no concomitant effect on the level of IkB{alpha} and {beta}-catenin, which are known substrates of a closely related SCF ligase.

  5. Stress-responsive JNK mitogen-activated protein kinase mediates aspirin-induced suppression of B16 melanoma cellular proliferation

    PubMed Central

    Ordan, Orly; Rotem, Ronit; Jaspers, Ilona; Flescher, Eliezer

    2003-01-01

    Available anticancer drugs do not seem to modify the prognosis of metastatic melanoma. Salicylate and acetyl salicylic acid (aspirin) were found to suppress growth in a number of transformed cells, that is, prostate and colon. Therefore, we studied the direct effects of aspirin on metastatic B16 melanoma cells. Aspirin at a plasma-attainable and nontoxic level suppressed the proliferation of B16 cells. Aspirin induced the activation of p38 and c-Jun N-terminal kinase (JNK) mitogen-activated protein kinases. Inhibition of JNK, but not p38, decreased the suppressive effect of aspirin upon the proliferation of B16 cells. The aspirin-induced reduction in B16 proliferation was cumulative over time. Aspirin and the chemotherapeutic drug 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) induced B16 cell death synergistically. In addition to the murine B16 cell line, the proliferation of SK-28 human melanoma cells was also suppressed by aspirin. In conclusion, aspirin suppresses the proliferation of metastatic B16 cells in a JNK-dependent mechanism. PMID:12684272

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

    SciTech Connect

    Rodriguez-Enriquez, Sara . E-mail: rodsar@mail.cardiologia.org.mx; Vital-Gonzalez, Paola A.; Flores-Rodriguez, Fanny L.; Marin-Hernandez, Alvaro; Ruiz-Azuara, Lena; Moreno-Sanchez, Rafael

    2006-09-01

    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{sub 5} values for HeLa cells lower than 0.5 {mu}M, whereas viability and proliferation of human lymphocytes were not affected by these drugs (IC{sub 5} > 30 {mu}M). 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.

  7. PUMILIO-2 Is Involved in the Positive Regulation of Cellular Proliferation in Human Adipose-Derived Stem Cells

    PubMed Central

    Shigunov, Patrícia; Kuligovski, Crisciele; de Aguiar, Alessandra Melo; Rebelatto, Carmen K.; Moutinho, José A.; Brofman, Paulo S.; Krieger, Marco A.; Goldenberg, Samuel; Munroe, David; Correa, Alejandro

    2012-01-01

    Stem cells can either differentiate into more specialized cells or undergo self-renewal. Several lines of evidence from different organisms suggest that these processes depend on the post-transcriptional regulation of gene expression. The presence of the PUF [Pumilio/FBF (fem-3 binding factor)] domain defines a conserved family of RNA binding proteins involved in repressing gene expression. It has been suggested that a conserved function of PUF proteins is to repress differentiation and sustain the mitotic proliferation of stem cells. In humans, Pumilio-2 (PUM2) is expressed in embryonic stem cells and adult germ cells. Here we show that PUM2 is expressed in a subpopulation of adipose-derived stem cell (ASC) cultures, with a granular pattern of staining in the cytoplasm. Protein levels of PUM2 showed no changes during the differentiation of ASCs into adipocytes. Moreover, RNAi knockdown of pum2 did not alter the rate of adipogenic differentiation compared with wild-type control cells. A ribonomic approach was used to identify PUM2-associated mRNAs. Microarray analysis showed that PUM2-bound mRNAs are part of gene networks involved in cell proliferation and gene expression control. We studied pum2 expression in cell cultures with low or very high levels of proliferation and found that changes in pum2 production were dependent on the proliferation status of the cell. Transient knockdown of pum2 expression by RNAi impaired proliferation of ASCs in vitro. Our results suggest that PUM2 does not repress differentiation of ASCs but rather is involved in the positive control of ASCs division and proliferation. PMID:21649561

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

    PubMed

    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.

  9. The expression of S100P increases and promotes cellular proliferation by increasing nuclear translocation of β-catenin in endometrial cancer.

    PubMed

    Guo, Luyan; Chen, Shuqin; Jiang, Hongye; Huang, Jiaming; Jin, Wenyan; Yao, Shuzhong

    2014-01-01

    There is increasing evidence suggesting that S100P has a significant role in cancer, and is associated with poor clinical outcomes. The expression of S100P mRNA and protein in endometrial cancer and normal endometrium tissues was detected by real-time quantitative RT-PCR and immunohistochemistry. Moreover, we reduced the expression of S100P in HEC-1A and Ishikawa endometrial cancer cell lines by siRNA transfection. Based on the reduced S100P mRNA expression, we measured the effects of S100P on cellular proliferation by the cell-counting kit-8. Nuclear β-catenin protein level was detected by western blotting. Cyclin D1 and c-myc mRNA expression regulated by β-catenin was detected by real-time quantitative RT-PCR. We found that the expression of S100P mRNA and protein increased in endometrial cancer tissues compared with the normal endometrium. Local S100P expression progressively increased from pathologic differenciation grade 1 to 3. After reducing the S100P expression, the cellular proliferation ability, nuclear β-catenin protein level, cyclin D1 and c-myc mRNA levels reduced. It indicated that S100P could promote cell proliferation by increasing nuclear translocation of β-catenin. The expression of S100P mRNA and protein in endometrial cancer significantly increased and is associated with pathologic differenciation grade. S100P may promote endometrial cell proliferation by increasing nuclear translocation of β-catenin.

  10. Relation of Internal Elastic Lamellar Layer Disruption to Neointimal Cellular Proliferation and Type III Collagen Deposition in Human Peripheral Artery Restenosis.

    PubMed

    Krishnan, Prakash; Purushothaman, K-Raman; Purushothaman, Meerarani; Baber, Usman; Tarricone, Arthur; Vasquez, Miguel; Wiley, Jose; Kini, Annapoorna; Sharma, Samin K; O'Connor, William N; Moreno, Pedro R

    2016-04-01

    Smooth muscle cell proliferation and extracellular matrix formation are responsible for disease progression in de novo and restenotic atherosclerosis. Internal elastic lamella (IEL) layer maintains the structural integrity of intima, and disruption of IEL may be associated with alterations in neointima, type III collagen deposition, and lesion progression in restenosis. Nineteen restenotic plaques (12 patients) procured during peripheral interventions were compared with 13 control plaques (12 patients) without restenosis. Hematoxylin & Eosin and elastic trichrome stains were used to measure length and percentage of IEL disruption, cellularity, and inflammation score. Type I and III collagens, smooth muscle cell (smc), fibroblast density, and nuclear proliferation (Ki67) percentage were evaluated by immunohistochemistry. IEL disruption percentage (28 ± 3.6 vs 6.1 ± 2.4; p = 0.0006), type III collagen content (0.33 ± 0.06 vs 0.17 ± 0.07; p = 0.0001), smc density (2014 ± 120 vs 923 ± 150; p = 0.0001), fibroblast density (2,282 ± 297 vs 906 ± 138; p = 0.0001), and Ki67 percentage (21.6 ± 2 vs 8.2 ± 0.65; p = 0.0001) were significantly increased in restenotic plaques compared to de novo plaques. Logistic regression analysis identified significant correlation between IEL disruption and neointimal smc density (r = 0.45; p = 0.01) and with type III collagen deposition (r = 0.61; p = 0.02) in restenosis. Increased IEL disruption may trigger cellular proliferation, altering collagen production, and enhancing restenotic neointima. In conclusion, understanding the pathologic and molecular basis of restenosis and meticulous-guided interventions oriented to minimize IEL damage may aid to reduce neointimal proliferation and the occurrence of restenosis. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Troglitazone acts on cellular pH and DNA synthesis through a peroxisome proliferator-activated receptor gamma-independent mechanism in breast cancer-derived cell lines.

    PubMed

    Turturro, Francesco; Friday, Ellen; Fowler, Rocky; Surie, Diya; Welbourne, Tomas

    2004-10-15

    The purpose of this study was to assess whether troglitazone (TRO) would induce cellular acidosis by inhibiting Na(+)/H(+) exchanger (NHE) 1 in breast carcinoma-derived cell lines and, if so, whether cellular acidosis would be associated with a reduction in proliferation. Intracellular pH (pH(i)) and acid extrusion capacity after an exogenous acid load were assayed using (2, 7)-biscarboxyethyl-5(6)-carboxyfluorescein in MCF-7 and MDA-MB-231 cells treated with TRO. Radiolabeled thymidine incorporation was used to assess DNA synthesis. Peroxisome proliferator-activated receptor (PPAR) gamma involvement was assessed using an antagonist and PPARgamma(-/-) NIH3T3 cells. TRO induced a prompt (<4 minute) and severe cellular acidosis in both MCF-7 (7.54 +/- 0.23 to 6.77 +/- 0.06; P < 0.001) and MDA-MB-231 cells (7.38 +/- 0.18 to 6.89 +/- 0.25; P < 0.05) after 12 minutes, without increasing acid production. Acid extrusion as assessed by the response to an exogenous acid load (NH(4)Cl pulse) was markedly blunted (MDA-MB-231, P < 0.01) or eliminated (MCF-7, P < 0.001). Chronic exposure to TRO resulted in NHE1 activity reduction (P < 0.05) and a dose-dependent decrease in DNA synthesis (<75% inhibition at 100 micromol/L; P < 0.001 and P < 0.01 for MCF-7 and MDA-MB-231, respectively) associated with a decreased number of viable cells. TRO-mediated inhibition of proliferation was not reversed by the presence of the PPARgamma inhibitor GW9662 and was demonstrable in PPARgamma(-/-) NIH3T3 cells, consistent with a PPARgamma-independent mechanism. TRO induces marked cellular acidosis in MCF-7 and MDA-MD-231 cells. Sustained acidosis is consonant with decreased proliferation and growth that is not reversed by a PPARgamma antagonist. Our results support a NHE-mediated action of TRO that exerts its effect independent of PPARgamma.

  12. Inhibition of mitochondrial fission prevents hypoxia-induced metabolic shift and cellular proliferation of pulmonary arterial smooth muscle cells.

    PubMed

    Parra, Valentina; Bravo-Sagua, Roberto; Norambuena-Soto, Ignacio; Hernández-Fuentes, Carolina P; Gómez-Contreras, Andrés G; Verdejo, Hugo E; Mellado, Rosemarie; Chiong, Mario; Lavandero, Sergio; Castro, Pablo F

    2017-07-22

    Chronic hypoxia exacerbates proliferation of pulmonary arterial smooth muscle cells (PASMC), thereby reducing the lumen of pulmonary arteries. This leads to poor blood oxygenation and cardiac work overload, which are the basis of diseases such as pulmonary artery hypertension (PAH). Recent studies revealed an emerging role of mitochondria in PAH pathogenesis, as key regulators of cell survival and metabolism. In this work, we assessed whether hypoxia-induced mitochondrial fragmentation contributes to the alterations of both PASMC death and proliferation. In previous work in cardiac myocytes, we showed that trimetazidine (TMZ), a partial inhibitor of lipid oxidation, stimulates mitochondrial fusion and preserves mitochondrial function. Thus, here we evaluated whether TMZ-induced mitochondrial fusion can prevent human PASMC proliferation in an in vitro hypoxic model. Using confocal fluorescence microscopy, we showed that prolonged hypoxia (48h) induces mitochondrial fragmentation along with higher levels of the mitochondrial fission protein DRP1. Concomitantly, both mitochondrial potential and respiratory rates decreased, indicative of mitochondrial dysfunction. In accordance with a metabolic shift towards non-mitochondrial ATP generation, mRNA levels of glycolytic markers HK2, PFKFB2 and GLUT1 increased during hypoxia. Incubation of PASMC with TMZ, prior to hypoxia, prevented all these changes and precluded the increase in PASMC proliferation. These findings were also observed using Mdivi-1 (a pharmacological DRP1 inhibitor) or a dominant negative DRP1 K38A as pre-treatments. Altogether, our data indicate that TMZ exerts a protective role against hypoxia-induced PASMC proliferation, by preserving mitochondrial function, thus highlighting DRP1-dependent morphology as a novel therapeutic approach for diseases such as PAH. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Expression and cellular distribution of estrogen and progesterone receptors and the real-time proliferation of porcine cumulus cells.

    PubMed

    Kempisty, Bartosz; Ziółkowska, Agnieszka; Ciesiółka, Sylwia; Piotrowska, Hanna; Antosik, Paweł; Bukowska, Dorota; Brüssow, Klaus P; Nowicki, Michał; Zabel, Maciej

    2015-12-01

    Although the expression of estrogen and progesterone receptors within porcine ovary and cumulus-oocyte complexes (COCs) is well recognized, still little information is known regarding expression of the progesterone receptor (PGR), PGR membrane component 1 (PGRMC1) and of estrogen-related receptors (ERRγ and ERRβ/γ) in separated cumulus cells in relation to real-time proliferation. In this study, a model of oocytes-separated cumulus cells was used to analyze the cell proliferation index and the expression PGR, PGRMC1 and of ERRγ and ERRβ/γ during 96-h cultivation in vitro using real-time quantitative PCR (qRT-PCR) and confocal microscopic observation. We found that PGR protein expression was increased at 0 h, compared with PGR protein expression after 96 h of culture (P < 0.001). The expression of PGRMC1, ERRγ and ERRβ/γ was unchanged. After using qRT-PCR we did not found statistical differences in expression of PGR, PGRMC1, ERRγ and ERRβ/γ during 96 h of cumulus cells in vitro culture (IVC). We supposed that the differential expression of the PGR protein at 0 h and after 96 h is related to a time-dependent down-regulation, which may activate a negative feedback. The distribution of PGR, PGRMC1 proteins may be linked with the translocation of receptors to the cytoplasm after the membrane binding of respective agonists and intra-cytoplasmic signal transduction. Furthermore, cumulus cells analyzed at 0 h were characterized by decreased proliferation index, whereas those after 96 h of culture revealed a significant increase of proliferation index, which may be associated with differentiation/luteinization of these cells during real-time proliferation.

  14. Tart cherry juice induces differential dose-dependent effects on apoptosis, but not cellular proliferation, in MCF-7 human breast cancer cells.

    PubMed

    Martin, Keith R; Wooden, Alissa

    2012-11-01

    Consumption of polyphenol-rich fruits, for example, tart cherries, is associated with a lower risk of cardiovascular disease and cancer. This is due, in large part, to the diverse myriad bioactive agents, that is, polyphenol anthocyanins, present in fruits. Anthocyanin-rich tart cherries purportedly modulate numerous cellular processes associated with oncogenesis such as apoptosis, cellular proliferation (CP), and cell cycle progression, although the effective concentrations eliciting these effects are unclear. We hypothesized that several dose-dependent effects over a large concentration range of 100% tart cherry juice (TCJ) would exist and affect these processes differentially with the potential for cellular protection and cellular death either by apoptosis or by necrosis. In this in vitro study, we tested the dose response of TCJ on CP and cell death in MCF-7 human breast cancer cells. TCJ was added at 0.03-30% (v/v) to cells and incubated overnight with the medium alone or with increasing TCJ. Bromodeoxyuridine incorporation was significantly reduced by 20% at ≥10% (v/v) TCJ and associated with necrosis, but was not different between the control and treatment groups at <10% TCJ. MTT reduction was also significantly reduced by 27% and 80% at 10% and 30% TCJ, respectively, and associated with necrosis. Apoptosis, but not necrosis, was increased ∼63% at 3% TCJ (∼307 nM monomeric anthocyanins), yet significantly decreased (P<.05) by 20% at 1% TCJ (920 nM) both of which were physiologically relevant concentrations of anthocyanins. The data support a biphasic effect on apoptosis and no effect on proliferation.

  15. Aberrant Wnt signalling and cellular over-proliferation in a novel mouse model of Meckel-Gruber syndrome.

    PubMed

    Wheway, Gabrielle; Abdelhamed, Zakia; Natarajan, Subaashini; Toomes, Carmel; Inglehearn, Chris; Johnson, Colin A

    2013-05-01

    Meckel-Gruber syndrome (MKS) is an embryonic lethal ciliopathy resulting from mutations in genes encoding proteins localising to the primary cilium. Mutations in the basal body protein MKS1 account for 7% of cases of MKS. The condition affects the development of multiple organs, including brain, kidney and skeleton. Here we present a novel Mks1(tm1a(EUCOMM)Wtsi) knockout mouse which accurately recapitulates the human condition, consistently developing pre-axial polydactyly, complex posterior fossa defects (including the Dandy-Walker malformation), and renal cystic dysplasia. TOPFlash Wnt reporter assays in mouse embryonic fibroblasts (MEFs) showed general de-regulated high levels of canonical Wnt/β-catenin signalling in Mks1(-/-) cells. In addition to these signalling defects, we also observed ectopic high proliferation in the brain and kidney of mutant animals at mid- to late-gestation. The specific role of Mks1 in regulating cell proliferation was confirmed in Mks1 siRNA knockdown experiments which showed increased levels of proliferation after knockdown, an effect not seen after knockdown of other ciliopathy genes. We suggest that this is a result of the de-regulation of multiple signalling pathways (Wnt, mTOR and Hh) in the absence of functional Mks1. This novel model system offers insights into the role of MKS1 in Wnt signalling and proliferation, and the impact of deregulation of these processes on brain and kidney development in MKS, as well as expanding our understanding of the role of Mks1 in multiple signalling pathways. Copyright © 2013 Elsevier Inc. All rights reserved.

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

    PubMed Central

    Turin, Ilaria; Potenza, Duilio Michele; Bottino, Cinzia; Glasnov, Toma N.; Ferulli, Federica; Mosca, Alessandra; Guerra, Germano; Rosti, Vittorio; Luinetti, Ombretta; Porta, Camillo; Pedrazzoli, Paolo

    2014-01-01

    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. PMID:25126575

  17. Clinical significance of telomerase activity in peritoneal lavage fluid from patients with gastric cancer and its relationship with cellular proliferation

    PubMed Central

    Da, Ming-Xu; Wu, Xiao-Ting; Guo, Tian-Kang; Zhao, Zi-Guang; Luo, Ting; Qian, Kun; Zhang, Ming-Ming; Wang, Jie

    2007-01-01

    AIM: To evaluate the efficacy of telomerase activity assay and peritoneal lavage cytology (PLC) examination in peritoneal lavage fluid for the prediction of peritoneal metastasis in gastric cancer patients, and to explore the relationship between telomerase activity and proliferating cell nuclear antigen expression. METHODS: Telomeric repeated amplification protocol (TRAP)-enzyme-linked immunosorbent assay (ELISA) was performed to measure the telomerase activity in 60 patients with gastric cancer and 50 with peptic ulcer. PLC analysis of the 60 patients with gastric cancer was used for comparison. The proliferating cell nuclear antigen (PCNA) in gastric carcinoma was immunohistochemically examined. RESULTS: The telomerase activity and PLC positive rate in peritoneal lavage fluid from patients with gastric cancer was 41.7% (25/60), and 25.0% (15/60), respectively. The positive rate of telomerase activity was significantly higher than that of PLC in the group of pT4 (15/16 vs 9/16, P < 0.05), P1-3 (13/13 vs 9/13, P < 0.05) and diffuse type (22/42 vs 13/42, P < 0.05). The patients with positive telomerase activity, peritoneal metastasis, and serosal invasion had significantly higher levels of average PCNA proliferation index (PI), (55.00 ± 6.59 vs 27.43 ± 7.72, 57.26 ± 10.18 vs 29.15 ± 8.31, and 49.82 ± 6.74 vs 24.65 ± 7.33, respectively, P < 0.05). CONCLUSION: The TRAP assay for telomerase activity is a useful adjunct for cytologic method in the diagnosis of peritoneal micrometastasis and well related to higher proliferating activity of gastric cancer. The results of this study also suggest a promising future therapeutic strategy for treating peritoneal dissemination based on telomerase inhibition. PMID:17589931

  18. In Vivo Bystander Effect: Cranial X-Irradiation Leads to Elevated DNA Damage, Altered Cellular Proliferation and Apoptosis, and Increased p53 Levels in Shielded Spleen

    SciTech Connect

    Koturbash, Igor; Loree, Jonathan; Kutanzi, Kristy; Koganow, Clayton; Pogribny, Igor; Kovalchuk, Olga

    2008-02-01

    Purpose: It is well accepted that irradiated cells may 'forward' genome instability to nonirradiated neighboring cells, giving rise to the 'bystander effect' phenomenon. Although bystander effects were well studied by using cell cultures, data for somatic bystander effects in vivo are relatively scarce. Methods and Materials: We set out to analyze the existence and molecular nature of bystander effects in a radiation target-organ spleen by using a mouse model. The animal's head was exposed to X-rays while the remainder of the body was completely protected by a medical-grade shield. Using immunohistochemistry, we addressed levels of DNA damage, cellular proliferation, apoptosis, and p53 protein in the spleen of control animals and completely exposed and head-exposed/body bystander animals. Results: We found that localized head radiation exposure led to the induction of bystander effects in the lead-shielded distant spleen tissue. Namely, cranial irradiation led to increased levels of DNA damage and p53 expression and also altered levels of cellular proliferation and apoptosis in bystander spleen tissue. The observed bystander changes were not caused by radiation scattering and were observed in two different mouse strains; C57BL/6 and BALB/c. Conclusion: Our study proves that bystander effects occur in the distant somatic organs on localized exposures. Additional studies are required to characterize the nature of an enigmatic bystander signal and analyze the long-term persistence of these effects and possible contribution of radiation-induced bystander effects to secondary radiation carcinogenesis.

  19. [Citophotometric expression of the factor of cellular proliferation ki-67 in the goiter colloid and in the papillary carcinoma of the thyroid].

    PubMed

    Souza, Gleim Dias de; Czeczko, Nicolau Gregori; Moreira, Hamilton; Ribas Filho, Jurandir Marcondes; Mafafaia, Osvaldo; Czeczko, Leticia Elizabeth Augustin; Thiele, Edilson Schwansee; Aguiar, Luiz Roberto Farion de

    2009-04-01

    To compare the cytophotometric quantitative expression of Ki-67 cellular proliferation factor in the colloid goiter with papillary carcinoma of the thyroid. The protein Ki-67 was studied with immunohistochemistry in 20 cases of papillary carcinoma of the thyroid and 12 cases of colloid goiter. The immunomarked cell nuclei were quantified through the software SAMBA 4000 and analyzed by software IMMUNO, considering variables index marker and optical density. The coefficient of the Spearman rank correlation and the non-parametric test of Mann-Whitney were estimated. There is significant difference between the goiter colloid and the papillary carcinoma of the thyroid in Ki-67 measurements, being bigger in papillary carcinomas. No difference was found in optical density. The correlation coefficient between the index marker and the optic density was 0,78. In colloid goiter, there was positive and significant association between the index marker and the optic density. For the papillary carcinoma of the thyroid the correlation between index marker and optic density was 0,18 (p = 0,572). There was no association between the index marker and the optic density in the carcinoma papillary of the thyroid. The cytophotometric expression of the Ki-67 showed higher cellular proliferation in the papillary carcinoma of the thyroid in comparison with in the colloid goiter.

  20. Inhibition of cellular proliferation by the Wilms' tumor suppressor WT1 is associated with suppression of insulin-like growth factor I receptor gene expression.

    PubMed Central

    Werner, H; Shen-Orr, Z; Rauscher, F J; Morris, J F; Roberts, C T; LeRoith, D

    1995-01-01

    We have investigated the regulation of the insulin-like growth factor I receptor (IGF-I-R) gene promoter by the Wilms' tumor suppressor WT1 in intact cells. The levels of endogenous IGF-I-R mRNA and the activity of IGF-I-R gene promoter fragments in luciferase reporter constructs were found to be significantly higher in G401 cells (a Wilms' tumor-derived cell line lacking detectable WT1 mRNA) than in 293 cells (a human embryonic kidney cell line which expresses significant levels of WT1 mRNA). To study whether WT1 could suppress the expression of the endogenous IGF-I-R gene, WT1-negative G401 cells were stably transfected with a WT1 expression vector. Expression of WT1 mRNA in G401 cells resulted in a significant decrease in the rate of cellular proliferation, which was associated with a reduction in the levels of IGF-I-R mRNA, promoter activity, and ligand binding and with a reduction in IGF-I-stimulated cellular proliferation, thymidine incorporation, and anchorage-independent growth. These data suggest that a major aspect of the action of the WT1 tumor suppressor is the repression of IGF-I-R gene expression. PMID:7791758

  1. Effects of antiinflammatory agents on mouse skin tumor promotion, epidermal DNA synthesis, phorbol ester-induced cellular proliferation, and production of plasminogen activator.

    PubMed

    Viaje, A; Slaga, T J; Wigler, M; Weinstein, I B

    1977-05-01

    The antinflammatory ateroids fluocinoine acetonide, fluocinonide, and fluclorolone acetonide were found to be very effectiveinhibitory agents of mouse skin tumor promotion. These steroids also drastically inhibited epidermal DNA synthesis and epidermal cellular proliferation induced by a phorbal ester tumor promoter. In addition, these compounds were potent inhibitors, of plasminogen activator production in tumor cell cultures. The clinically used non-steroidal antiinflammatory agents oxyphenbutazone, indomethacin, and Seclazone also inhibite tumor promotion but were much less effective. Although these agents are useful against inflammatory disorders in general when given p.o., in our studies they had little effect on inflammation and epidermal cellular proliferation induced by a phorbol ester tumor promoter when given topically. The afore mentioned nonsteroidal antiinflammatory agents also had little effect on epidermal DNA synthesis. Oxyphenbutazone and indomethacin were less potent inhibitors of plasminogen activator production in tumor cells than were the antiinflammatory steroids, and Seclazone produced a negligible inhibition. There is, therefore, a general correlation in the potencies of a series of steroidal antiinflammatory agents for inhibition of tumor promotion and their ability to inhibit plasminogen activator production by tumor cell cultures and epidermal DNA synthesis.

  2. Cellular proliferation in the skin of X-rayed newt limbs (with a note on x-ray-induced limb regression)

    SciTech Connect

    Wertz, R.L.

    1982-07-01

    Left hind limbs, including the pelvis, of adult newts (Notophthalmus viridescens) were locally irradiated with a dose of x-rays that inhibited regeneration (2,000 R). This x-ray dose and other doses (700-2,000 R) capable of inhibiting limb regeneration also cause limb regression prior to amputation. Before limb regression occurred, there was a latent period of 3 to 6 weeks. Limb regression was characterized by necrotic wasting and resorption of distal elements. The degree of loss was variable and dependent upon dosage. After this further degenerative changes were not noted. Proliferation of epidermal cells was examined 4 days after irradiation prior to limb regression or after x-ray-induced degeneration of the limbs had ended. Proliferative activity in x-rayed limbs was also compared at various stages of contralateral control limb regeneration. Limbs examined after x-ray-induced limb regression had ended showed levels of (/sup 3/H)-thymidine incorporation into DNA comparable to normal epidermis. In contrast, limbs examined 4 days after irradiation had lower levels of DNA synthesis (P much less than 0.01). Amputation of limbs in both groups caused an increase in DNA synthesis (P much less than 0.01). Histological examination showed that cellular proliferation was associated primarily with the epidermis. These results indicate that epidermal cell proliferation was not resistant to x-rays. However, levels of normal cell division were observed after amputation of after cessation of x-ray-induced limb regression.

  3. Downregulation of cellular prion protein inhibited the proliferation and invasion and induced apoptosis of Marek's disease virus-transformed avian T cells

    PubMed Central

    Wan, Xuerui; Yang, Runxia; Liu, Guilin; Zhu, Manling; Zhang, Tianliang; Liu, Lei

    2016-01-01

    Cellular prion protein (PrPC) is ubiquitously expressed in the cytomembrane of a considerable number of eukaryotic cells. Although several studies have investigated the functions of PrPC in cell proliferation, cell apoptosis, and tumorigenesis of mammals, the correlated functions of chicken PrPC (chPrPC) remain unknown. In this study, stable chPrPC-downregulated Marek's disease (MD) virus-transformed avian T cells (MSB1-SiRNA-3) were established by introducing short interfering RNA (SiRNA) targeting chicken prion protein genes. We found that downregulation of chPrPC inhibits proliferation, invasion, and migration, and induces G1 cell cycle phase arrest and apoptosis of MSB1-SiRNA-3 cells compared with Marek's disease virus-transformed avian T cells (MSB1) and negative control cells. To the best of our knowledge, the present study provides the first evidence supporting the positive correlation between the expression level of chPrPC and the proliferation, migration, and invasion ability of MSB1 cells, but appears to protect MSB1 cells from apoptosis, which suggests it functions in the formation and development of MD tumors. This evidence may contribute to future research into the specific molecular mechanisms of chPrPC in the formation and development of MD tumors. PMID:26243599

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

    PubMed Central

    Rampuria, Pragya

    2015-01-01

    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. PMID:25710490

  5. Integrin α5 Suppresses the Phosphorylation of Epidermal Growth Factor Receptor and Its Cellular Signaling of Cell Proliferation via N-Glycosylation*

    PubMed Central

    Hang, Qinglei; Isaji, Tomoya; Hou, Sicong; Im, Sanghun; Fukuda, Tomohiko; Gu, Jianguo

    2015-01-01

    Integrin α5β1-mediated cell adhesion regulates a multitude of cellular responses, including cell proliferation, survival, and cross-talk between different cellular signaling pathways. Integrin α5β1 is known to convey permissive signals enabling anchorage-dependent receptor tyrosine kinase signaling. However, the effects of integrin α5β1 on cell proliferation are controversial, and the molecular mechanisms involved in the regulation between integrin α5β1 and receptor tyrosine kinase remain largely unclear. Here we show that integrin α5 functions as a negative regulator of epidermal growth factor receptor (EGFR) signaling through its N-glycosylation. Expression of WT integrin α5 suppresses the EGFR phosphorylation and internalization upon EGF stimulation. However, expression of the N-glycosylation mutant integrin α5, S3–5, which contains fewer N-glycans, reversed the suppression of the EGFR-mediated signaling and cell proliferation. In a mechanistic manner, WT but not S3–5 integrin α5 forms a complex with EGFR and glycolipids in the low density lipid rafts, and the complex formation is disrupted upon EGF stimulation, suggesting that the N-glycosylation of integrin α5 suppresses the EGFR activation through promotion of the integrin α5-glycolipids-EGFR complex formation. Furthermore, consistent restoration of those N-glycans on the Calf-1,2 domain of integrin α5 reinstated the inhibitory effects as well as the complex formation with EGFR. Taken together, these data are the first to demonstrate that EGFR activation can be regulated by the N-glycosylation of integrin α5, which is a novel molecular paradigm for the cross-talk between integrins and growth factor receptors. PMID:26483551

  6. Integrin α5 Suppresses the Phosphorylation of Epidermal Growth Factor Receptor and Its Cellular Signaling of Cell Proliferation via N-Glycosylation.

    PubMed

    Hang, Qinglei; Isaji, Tomoya; Hou, Sicong; Im, Sanghun; Fukuda, Tomohiko; Gu, Jianguo

    2015-12-04

    Integrin α5β1-mediated cell adhesion regulates a multitude of cellular responses, including cell proliferation, survival, and cross-talk between different cellular signaling pathways. Integrin α5β1 is known to convey permissive signals enabling anchorage-dependent receptor tyrosine kinase signaling. However, the effects of integrin α5β1 on cell proliferation are controversial, and the molecular mechanisms involved in the regulation between integrin α5β1 and receptor tyrosine kinase remain largely unclear. Here we show that integrin α5 functions as a negative regulator of epidermal growth factor receptor (EGFR) signaling through its N-glycosylation. Expression of WT integrin α5 suppresses the EGFR phosphorylation and internalization upon EGF stimulation. However, expression of the N-glycosylation mutant integrin α5, S3-5, which contains fewer N-glycans, reversed the suppression of the EGFR-mediated signaling and cell proliferation. In a mechanistic manner, WT but not S3-5 integrin α5 forms a complex with EGFR and glycolipids in the low density lipid rafts, and the complex formation is disrupted upon EGF stimulation, suggesting that the N-glycosylation of integrin α5 suppresses the EGFR activation through promotion of the integrin α5-glycolipids-EGFR complex formation. Furthermore, consistent restoration of those N-glycans on the Calf-1,2 domain of integrin α5 reinstated the inhibitory effects as well as the complex formation with EGFR. Taken together, these data are the first to demonstrate that EGFR activation can be regulated by the N-glycosylation of integrin α5, which is a novel molecular paradigm for the cross-talk between integrins and growth factor receptors.

  7. Effects of 5-fluorouracil in nuclear and cellular morphology, proliferation, cell cycle, apoptosis, cytoskeletal and caveolar distribution in primary cultures of smooth muscle cells.

    PubMed

    Filgueiras, Marcelo de Carvalho; Morrot, Alexandre; Soares, Pedro Marcos Gomes; Costa, Manoel Luis; Mermelstein, Cláudia

    2013-01-01

    Colon cancer is one of the most prevalent types of cancer in the world and is one of the leading causes of cancer death. The anti-metabolite 5- fluorouracil (5-FU) is widely used in the treatment of patients with colon cancer and other cancer types. 5-FU-based chemotherapy has been shown to be very efficient in the improvement of overall survival of the patients and for the eradication of the disease. Unfortunately, common side effects of 5-FU include severe alterations in the motility of the gastrointestinal tissues. Nevertheless, the molecular and cellular effects of 5-FU in smooth muscle cells are poorly understood. Primary smooth muscle cell cultures are an important tool for studies of the biological consequences of 5-FU at the cellular level. The avian gizzard is one of the most robust organs of smooth muscle cells. Here we studied the molecular and cellular effects of the chemotherapic drug 5-FU in a primary culture of chick gizzard smooth muscle cells. We found that treatment of smooth muscle cells with 5-FU inhibits cell proliferation by the arrest of cells in the G1 phase of cell cycle and induce apoptosis. 5-FU induced a decrease in the percentage of histone H3-positive cells. Treatment of cells with 5-FU induced changes in cellular and nuclear morphology, a decrease in the number of stress fibers and a major decrease in the number of caveolin-3 positive cells. Our results suggest that the disorganization of the actin cytoskeleton and the reduction of caveolin-3 expression could explain the alterations in contractility observed in patients treated with 5-FU. These findings might have an impact in the understanding of the cellular effects of 5-FU in smooth muscle tissues and might help the improvement of new therapeutic protocols for the treatment of colon cancer.

  8. Inhibition of cellular proliferation and enhancement of hydrogen peroxide production in fibrosarcoma cell line by weak radio frequency magnetic fields.

    PubMed

    Castello, Pablo R; Hill, Iain; Sivo, Frank; Portelli, Lucas; Barnes, Frank; Usselman, Robert; Martino, Carlos F

    2014-12-01

    This study presents experimental data for the effects of weak radio frequency (RF) magnetic fields on hydrogen peroxide (H2O2) production and cellular growth rates of fibrosarcoma HT1080 cells in vitro. Cells were exposed either to 45 µT static magnetic fields (SMFs)-oriented vertical to the plane of growth or to SMFs combined with weak 5 and 10 MHz RF magnetic fields of 10 µTRMS intensity perpendicular to the static field. Cell numbers were reduced up to 30% on Day 2 for the cells exposed to the combination of SMF and a 10 MHz RF magnetic field compared with the SMF control cells. In addition, cells exposed to 10 MHz RF magnetic fields for 8 h increased H2O2 production by 55%. The results demonstrate an overall magnetic field-induced biological effect that shows elevated H2O2 levels with accompanying decrease in cellular growth rates.

  9. Ki-1/57 and CGI-55 ectopic expression impact cellular pathways involved in proliferation and stress response regulation.

    PubMed

    Costa, Fernanda C; Saito, Angela; Gonçalves, Kaliandra A; Vidigal, Pedro M; Meirelles, Gabriela V; Bressan, Gustavo C; Kobarg, Jörg

    2014-12-01

    Ki-1/57 (HABP4) and CGI-55 (SERBP1) are regulatory proteins and paralogs with 40.7% amino acid sequence identity and 67.4% similarity. Functionally, they have been implicated in the regulation of gene expression on both the transcriptional and mRNA metabolism levels. A link with tumorigenesis is suggested, since both paralogs show altered expression levels in tumor cells and the Ki-1/57 gene is found in a region of chromosome 9q that represents a haplotype for familiar colon cancer. However, the target genes regulated by Ki-1/57 and CGI-55 are unknown. Here, we analyzed the alterations of the global transcriptome profile after Ki-1/57 or CGI-55 overexpression in HEK293T cells by DNA microchip technology. We were able to identify 363 or 190 down-regulated and 50 or 27 up-regulated genes for Ki-1/57 and CGI-55, respectively, of which 20 were shared between both proteins. Expression levels of selected genes were confirmed by qRT-PCR both after protein overexpression and siRNA knockdown. The majority of the genes with altered expression were associated to proliferation, apoptosis and cell cycle control processes, prompting us to further explore these contexts experimentally. We observed that overexpression of Ki-1/57 or CGI-55 results in reduced cell proliferation, mainly due to a G1 phase arrest, whereas siRNA knockdown of CGI-55 caused an increase in proliferation. In the case of Ki-1/57 overexpression, we found protection from apoptosis after treatment with the ER-stress inducer thapsigargin. Together, our data give important new insights that may help to explain these proteins putative involvement in tumorigenic events. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Long non-coding RNA CCAT2 functions as an oncogene in hepatocellular carcinoma, regulating cellular proliferation, migration and apoptosis

    PubMed Central

    ZHOU, NING; SI, ZHONGZHOU; LI, TING; CHEN, GUANGSHUN; ZHANG, ZHONGQIANG; QI, HAIZHI

    2016-01-01

    An increasing number of studies have demonstrated that the dysregulation of long non-coding RNAs (lncRNAs) may serve an important role in tumor progression. Previous studies have reported that the lncRNA, colon cancer associated transcript 2 (CCAT2), was highly expressed in various tumors. However, the function of CCAT2 in hepatocellular carcinoma (HCC) has not yet been elucidated. The aim of the present study was to identify novel oncogene lncRNAs and investigate their physiological function and mechanism in HCC. Using reverse transcription-quantitative polymerase chain reaction, it was observed that CCAT2 was upregulated in HCC tissues and human HCC cell lines. Furthermore, the impacts of CCAT2 on cell proliferation, migration and apoptosis were analyzed using cell migration, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and enzyme-linked immunosorbent assay analysis respectively. The overexpression of CCAT2 using a synthesized vector significantly promoted cell migration and proliferation, and inhibited apoptosis of HCC cells in vitro. The suppression of CCAT2 expression resulted in opposing effects. To the best of our knowledge, the present study is the first to demonstrate that CCAT2 functions as a oncogene in HCC. Further investigation is required to clarify the molecular mechanisms of this lncRNA in HCC development. PMID:27347113

  11. Effect of artemisia species on cellular proliferation and apoptosis in human breast cancer cells via estrogen receptor-related pathway.

    PubMed

    Choi, Eunjeong; Kim, Gunhee

    2013-10-01

    To investigate the mechanism underlying the anticancer effect of Artemisia species through the inhibition of cell growth and induction of apoptosis in breast carcinoma cells. To evaluate the anticancer activity of methanol extracts of eight Artemisia species (Artemisia stolonifera, Artemisia selengensis, Artemisia japonica, Artemisia Montana, Artemisia capillaris, Artemisia sylvatica, Artemisia keiskeana, and Artemisia scoparia), we first investigated the proliferation of estrogen receptor (ER)-positive MCF-7 breast carcinoma cells exposed to 5 or 200 g/mL for 72 h. Apoptosis induction was assessed by an Annexin V binding assay in cells exposed to extracts at a high concentration (200 g/mL). To verify the mechanism of apoptosis, ER expression and its related signaling was investigated using an immunoblot assay under the same conditions. MCF-7 cells showed the strongest antiproliferative response to the tested extracts. However, a biphasic effect was observed: the extracts inhibited proliferation at high concentrations whereas they stimulated it at low ones. ER expression was similarly modulated by the extracts. However, all of the extracts induced apoptosis at a high concentration (200 g/mL). Compared to the control level, exposure to the extracts resulted in a remarkable increase in the shift of cell populations. The present study suggests that the tested Artemisia species exerted their anticancer effects through the induction of apoptosis via an ER-related pathway.

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

    PubMed

    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.

  13. Fatty Acid Synthase as a Factor Required for Exercise-Induced Cognitive Enhancement and Dentate Gyrus Cellular Proliferation

    PubMed Central

    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. PMID:24223732

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

    PubMed

    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

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

    SciTech Connect

    Ondovcik, Stephanie L.; Tamblyn, Laura; McPherson, John Peter; Wells, Peter G.

    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

  16. Study on connexin gene and protein expression and cellular distribution in relation to real-time proliferation of porcine granulosa cells.

    PubMed

    Kempisty, B; Ziółkowska, A; Ciesiółka, S; Piotrowska, H; Antosik, P; Bukowska, D; Nowicki, M; Brüssow, K P; Zabel, M

    2014-01-01

    Granulosa cells (GCs) play an important role during follicle growth and development in preovulatory stage. Moreover, the proteins such as connexins are responsible for formation of protein channel between follicular-cumulus cells and oocyte. This study was aimed to investigate the role of connexin expression in porcine GCs in relation to their cellular distribution and real-time cell proliferation. In the present study, porcine GCs were isolated from the follicles of puberal gilts and then cultured in a real-time cellular analyzer (RTCA) system for 168 h. The expression levels of connexins (Cxs) Cx36, Cx37, Cx40 and Cx43 mRNA were measured by RQ-PCR analysis, and differences in the expression and distribution of Cx30, Cx31, Cx37, Cx43 and Cx45 proteins were analyzed by confocal microscopic visualization. We found higher level of Cx36, Cx37, and Cx43 mRNA expression in GCs at recovery (at 0 h of in vitro culture, IVC) compared to all analyzed time periods of IVC (24, 48, 72, 96, 120, 144 and 168 h; P<0.001). On the other hand, the expression level of Cx40 transcripts was higher after 24 h of IVC compared to 0 h and the other times of IVC (P<0.001). Similarly to mRNAs, the expression levels of Cx31, Cx37 and Cx45 proteins were higher before (0 h) compared to after 168 h of IVC. The expression of Cx30 and Cx43, however, did not vary between the groups. In all, the proteins were distributed throughout the cell membrane rather than in the cytoplasm both before and after IVC. After 24 h of IVC, we observed a significant increase in the proliferation of GCs (log phase). We found differences in the proliferation index between 72-96 and 96- 140 h within the same population of GCs. In conclusion, the decrease in the expression of Cx mRNAs and proteins following IVC could be associated with a breakdown in gap-junction connections (GJCs), and leads to the decreased of their activity, which may be a reason of non-functional existence of connexon in follicular granulosa cells

  17. Induction of experimental allergic encephalomyelitis in Lewis rats with purified synthetic peptides: delineation of antigenic determinants for encephalitogenicity, in vitro activation of cellular transfer, and proliferation of lymphocytes.

    PubMed Central

    Mannie, M D; Paterson, P Y; U'Prichard, D C; Flouret, G

    1985-01-01

    Four highly purified synthetic peptides encompassing segments of the 68-86 region [for the numbering system used, see Eylar, E.H., Brostoff, S., Hashim, G., Caccam, J. & Burnett, P. (1971) J. Biol. Chem. 246, 5770-5784] of myelin basic protein (MBP), a region known to induce experimental allergic encephalomyelitis (EAE) in Lewis rats, were used to define and compare structure-function relationships between the primary structure of the 68-86 sequence and the three following biological activities: induction of EAE in Lewis rats, stimulation of T lymphocytes in vitro as measured by augmented cellular transfer of EAE to syngeneic recipients, and lymphocyte proliferation, as measured by [3]thymidine incorporation. Guinea pig (GP) MBP was approximately 60 or 1500 times more active than the GP68-84 (Y G S L P Q K S Q R S Q D E N; single-letter amino acid abbreviations) or the modified bovine (MB) 68-84 (Y G S L P Q K A Q R P Q D E N) peptides for induction of EAE, respectively. Furthermore, lymphocytes primed with either GPMBP, GP68-84, or MB68-84 crossreacted in vitro with either GPMBP, GP68-84, or MB68-84 for activation of lymphocyte transfer activity. In contrast, lymphocytes primed with either GP68-84 or MB68-84 exhibited antigen-specific proliferation in vitro exclusively in response to either GP or MB sequences, respectively. Neither GP75-84 (S Q R S Q D E N) nor GP75-86 (S Q R S Q D E N P V) induced EAE, activated lymphocytes for EAE transfer, or stimulated lymphocyte proliferation under conditions and doses tested. We conclude that (i) structurally distinct determinants, reflecting existence of functionally independent classes of antigen receptors, specify encephalitogenic and proliferative responses of primed lymphocytes and (ii) determinants for EAE induction, cellular transfer of EAE, and lymphocyte proliferation include amino acid residues in the 68-74 (Y G S L P Q K) sequence of GPMBP. PMID:3875098

  18. MicroRNA-181b inhibits cellular proliferation and invasion of glioma cells via targeting Sal-like protein 4.

    PubMed

    Zhou, Yu; Peng, Yong; Liu, Min; Jiang, Yugang

    2016-11-17

    MicroRNAs (miRs), a class of 18-25 nucleotides in length non-coding RNAs, are able to suppress gene expression by targeting complementary regions of mRNAs and inhibiting protein translation Recently, miR-181b was found to playa suppressive role in glioma, but the regulatory mechanism of miR-181b in the malignant phenotypes of glioma cells remains largely unclear. Here we found that miR-181b was significantly downregulated in glioma tissues when compared with normal brain tissues, and decreased miR-181b levels were significantly associated with high pathology grade and poor prognosis of patients with glioma. Moreover, miR-181b was also downregulated in glioma cell lines (U87, SHG44, U373, and U251) compared to normal astrocytes. Overexpression of miR-181b significantly decreased the proliferation, migration, and invasion of glioma U251 cells. Sal-like protein 4 (SALL4) was identified as a novel target gene of miR-181b in U251 cells. The expression of SALL4 was significantly upregulated in glioma tissues and cell lines, and an inverse correlation was observed between the miR-181b and SALL4 expression levels in glioma. Further investigation showed that the protein expression of SALL4 was negatively regulated by miR-181b in U251 cells. Knockdown of SALL4 significantly inhibited the proliferation, migration and invasion of U251 cells, while overexpression of SALL4 effectively reversed the suppressive effects of miR-181b on these malignant phenotypes of U251 cells. In conclusion, our study demonstrates that miR-181b has suppressive effects on the malignant phenotypes of glioma cells, partly at least, via directly targeting SALL4. Therefore, the miR-181b/SALL4 axis may become a potential therapeutic target for glioma.

  19. Grape seed and red wine polyphenol extracts inhibit cellular cholesterol uptake, cell proliferation, and 5-lipoxygenase activity.

    PubMed

    Leifert, Wayne R; Abeywardena, Mahinda Y

    2008-12-01

    Accumulating evidence suggests that grape seed and wine polyphenol extracts possess a diverse array of actions and may be beneficial in the prevention of inflammatory-mediated disease such as cardiovascular disease and cancer. This study aimed to determine whether the reported pleiotropic effects of several polyphenolic extracts from grape seed products or red wine would also include inhibition of cholesterol uptake and cell proliferation, and inhibit a known specific target of the inflammatory process, that is, 5-lipoxygenase (5-LOX). Incubation of HT29, Caco2, HepG2, or HuTu80 cells in a medium containing [(3)H]cholesterol in the presence of a grape seed extract (GSE) or red wine polyphenolic compounds (RWPCs) inhibited [(3)H]cholesterol uptake by up to 66% (which appeared maximal). The estimated IC(50) values were 60 and 83 microg/mL for RWPC and GSE, respectively. Similar cholesterol uptake inhibitory effects were observed using the fluorescent cholesterol analogue NBD cholesterol. The inhibition of cholesterol uptake was independent of the sample's (GSE and RWPC) potent antioxidative capacity. Red wine polyphenolic compound and GSE dose dependently inhibited HT29 colon adenocarcinoma cell proliferation, which was accompanied by an increase in apoptosis. In addition, RWPC and GSE inhibited 5-LOX activity with the IC(50) values being 35 and 13 microg/mL, respectively. Two of 3 other GSEs tested also significantly inhibited 5-LOX activity. Inhibition of cholesterol uptake and proinflammatory 5-LOX activity may be beneficial in preventing the development of chronic degenerative diseases such as cardiovascular disease and cancer.

  20. Imaging of cellular proliferation in liver metastasis by [18F]fluorothymidine positron emission tomography: effect of therapy.

    PubMed

    Contractor, Kaiyumars; Challapalli, Amarnath; Tomasi, Giampaolo; Rosso, Lula; Wasan, Harpreet; Stebbing, Justin; Kenny, Laura; Mangar, Stephen; Riddle, Pippa; Palmieri, Carlo; Al-Nahhas, Adil; Sharma, Rohini; Turkheimer, Federico; Coombes, R Charles; Aboagye, Eric

    2012-06-07

    Although [(18)F]fluorothymidine positron emission tomography (FLT-PET) permits estimation of tumor thymidine kinase-1 expression, and thus, cell proliferation, high physiological uptake of tracer in liver tissue can limit its utility. We evaluated FLT-PET combined with a temporal-intensity information-based voxel-clustering approach termed kinetic spatial filtering (FLT-PET(KSF)) for detecting drug response in liver metastases. FLT-PET and computed tomography data were collected from patients with confirmed breast or colorectal liver metastases before, and two weeks after the first cycle of chemotherapy. Changes in tumor FLT-PET and FLT-PET(KSF) variables were determined. Visual distinction between tumor and normal liver was seen in FLT-PET(KSF) images. Of the 33 metastases from 20 patients studied, 26 were visible after kinetic filtering. The net irreversible retention of the tracer (Ki; from unfiltered data) in the tumor, correlated strongly with tracer uptake when the imaging variable was an unfiltered average or maximal standardized uptake value, 60 min post-injection (SUV(60,av): r = 0.9, SUV(60,max): r = 0.7; p < 0.0001 for both) and occurrence of high intensity voxels derived from FLT-PET(KSF) (r = 0.7, p < 0.0001). Overall, a significant reduction in the imaging variables was seen in responders compared to non-responders; however, the two week time point selected for imaging was too early to allow prediction of long term clinical benefit from chemotherapy. FLT-PET and FLT-PET(KSF) detected changes in proliferation in liver metastases.

  1. Imaging of cellular proliferation in liver metastasis by [18F]fluorothymidine positron emission tomography: effect of therapy

    NASA Astrophysics Data System (ADS)

    Contractor, Kaiyumars; Challapalli, Amarnath; Tomasi, Giampaolo; Rosso, Lula; Wasan, Harpreet; Stebbing, Justin; Kenny, Laura; Mangar, Stephen; Riddle, Pippa; Palmieri, Carlo; Al-Nahhas, Adil; Sharma, Rohini; Turkheimer, Federico; Coombes, R. Charles; Aboagye, Eric

    2012-06-01

    Although [18F]fluorothymidine positron emission tomography (FLT-PET) permits estimation of tumor thymidine kinase-1 expression, and thus, cell proliferation, high physiological uptake of tracer in liver tissue can limit its utility. We evaluated FLT-PET combined with a temporal-intensity information-based voxel-clustering approach termed kinetic spatial filtering (FLT-PETKSF) for detecting drug response in liver metastases. FLT-PET and computed tomography data were collected from patients with confirmed breast or colorectal liver metastases before, and two weeks after the first cycle of chemotherapy. Changes in tumor FLT-PET and FLT-PETKSF variables were determined. Visual distinction between tumor and normal liver was seen in FLT-PETKSF images. Of the 33 metastases from 20 patients studied, 26 were visible after kinetic filtering. The net irreversible retention of the tracer (Ki; from unfiltered data) in the tumor, correlated strongly with tracer uptake when the imaging variable was an unfiltered average or maximal standardized uptake value, 60 min post-injection (SUV60,av: r = 0.9, SUV60,max: r = 0.7; p < 0.0001 for both) and occurrence of high intensity voxels derived from FLT-PETKSF (r = 0.7, p < 0.0001). Overall, a significant reduction in the imaging variables was seen in responders compared to non-responders; however, the two week time point selected for imaging was too early to allow prediction of long term clinical benefit from chemotherapy. FLT-PET and FLT-PETKSF detected changes in proliferation in liver metastases.

  2. Nutrient-Dependent Efficacy of the Antifungal Protein YvgO Correlates to Cellular Proliferation Rate in Candida albicans 3153A and Byssochlamys fulva H25.

    PubMed

    Manns, David C; Churey, John J; Worobo, Randy W

    2014-12-01

    YvgO is a recently characterized antifungal protein isolated from Bacillus thuringiensis SF361 that exhibits a broad spectrum of activity and pH stability. Customized colorimetric metabolic assays based on standard broth microdilution techniques were used to determine the variable tolerance of Byssochlamys fulva H25 and Candida albicans 3153A to YvgO exposure under select matrix conditions impacting cellular proliferation. Normalization of the solution pH after antifungal challenge expanded the available pH range under consideration allowing for a comprehensive in vitro assessment of YvgO efficacy. Indicator susceptibility was examined across an array of elementary growth-modifying conditions, including media pH, incubation temperature, ionic strength, and carbohydrate supplementation. Under suboptimal temperature and pH conditions, the indicator growth rate reduced, and YvgO-mediated susceptibility was attenuated. While YvgO association but not efficacy was somewhat influenced by solution ionic strength, carbohydrate supplementation was shown to be the most influential susceptibility factor, particularly for C. albicans. Although the specific choice of carbohydrate/nutrient supplement dictated the extent of enhanced YvgO efficacy, D-glucose additionally improved the association between antifungal and target. Indeed, when exposed to YvgO under conditions that lead to increased cellular proliferation, both indicators displayed a stronger association and susceptibility to YvgO when compared to carbohydrate-deprived media or suboptimal incubation environments. With further study, YvgO may have the capacity to function as a prophylaxis for food safety and preservation, as well as a pharmaceutical agent against opportunistic fungal pathogens either independently or in combination with other established treatments applied to both livestock and human health concerns.

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

    PubMed

    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.

  4. Reptilian spermatogenesis: A histological and ultrastructural perspective.

    PubMed

    Gribbins, Kevin M

    2011-07-01

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

  5. Flame synthesis and in vitro biocompatibility assessment of superparamagnetic iron oxide nanoparticles: cellular uptake, toxicity and proliferation studies.

    PubMed

    Buyukhatipoglu, K; Miller, T A; Clyne, A Morss

    2009-12-01

    Superparamagnetic iron oxide nanoparticles are used in diverse applications, such as targeted drug delivery, magnetic resonance imaging and hyperthermic malignant cell therapy. In the current work, superparamagnetic iron oxide nanoparticles were produced by flame synthesis, which has improved nanoparticle property control and is capable of commercial production rates with minimal post-processing. The iron oxide nanoparticle material characteristics were analyzed by electron microscopy and Raman spectroscopy. Finally, flame synthesized iron oxide nanoparticle interaction with endothelial cells was compared to commercially available iron oxide nanoparticles. Flame synthesis produced a heterogeneous mixture of 6-12 nm diameter hematite and magnetite nanoparticles with superparamagnetic properties. Endothelial cell scanning electron microscopy, confirmed by energy dispersive spectroscopy, demonstrated that flame synthesized nanoparticles are ingested into cells in a similar manner to commercially available nanoparticles. The flame synthesized particles showed no statistically significant toxicity difference from commercially available nanoparticles, as measured by Live/Dead assay, Alamar blue, and lactase dehydrogenase release. Neither type of nanoparticle affected cell proliferation induced by fibroblast growth factor-2. These data suggest that combustion synthesized iron oxide nanoparticles are comparable to commercially available nanoparticles for biological applications, yet flame synthesis is a simpler process with higher purity products and lower manufacturing costs. Future work will include functionalizing nanoparticles for specific cell targeting and bioactive factor delivery.

  6. FGF-10 and specific structural elements of dermatan sulfate size and sulfation promote maximal keratinocyte migration and cellular proliferation

    PubMed Central

    Radek, Katherine A.; Taylor, Kristen R.; Gallo, Richard L.

    2009-01-01

    Fibroblast growth factor-10 (FGF-10) is essential for epithelial development, while other members of this family, such as FGF-7, are not. FGF-10 is abundantly released into wounds following injury, and likely an essential growth factor required for this process. To evaluate how activation of this growth factor is controlled, multiple glycosaminoglycans were combined with FGF-10 assayed by measurement of the proliferation of cell lines expressing FGF receptor-2-IIIb, or keratinocyte migration in an in vitro wound repair assay. Dermatan sulfate (DS) exhibited greater potency than heparan sulfate or other chondroitin sulfates found in wounds. Structural variants of DS between 10 and 20 disaccharides containing iduronic acid showed maximal capacity to enable FGF-10 receptor stimulation. Furthermore, FGF-10 and DS markedly enhanced migration of keratinocytes in an in vitro wound scratch assay, while FGF-7 or other glycosaminoglycans did not. These data strongly suggest that FGF-10 activity is uniquely important in wound repair and that specific DS structural properties are necessary to promote FGF-10 function. These observations identify a novel interplay between DS and FGF-10 in mediating wound repair. PMID:19152659

  7. Proteomic analysis of lithium-induced nephrogenic diabetes insipidus: Mechanisms for aquaporin 2 down-regulation and cellular proliferation

    PubMed Central

    Nielsen, Jakob; Hoffert, Jason D.; Knepper, Mark A.; Agre, Peter; Nielsen, Søren; Fenton, Robert A.

    2008-01-01

    Lithium is a commonly prescribed mood-stabilizing drug. However, chronic treatment with lithium induces numerous kidney-related side effects, such as dramatically reduced aquaporin 2 (AQP2) abundance, altered renal function, and structural changes. As a model system, inner medullary collecting ducts (IMCD) isolated from rats treated with lithium for either 1 or 2 weeks were subjected to differential 2D gel electrophoresis combined with mass spectrometry and bioinformatics analysis to identify (i) signaling pathways affected by lithium and (ii) unique candidate proteins for AQP2 regulation. After 1 or 2 weeks of lithium treatment, we identified 6 and 74 proteins with altered abundance compared with controls, respectively. We randomly selected 17 proteins with altered abundance caused by lithium treatment for validation by immunoblotting. Bioinformatics analysis of the data indicated that proteins involved in cell death, apoptosis, cell proliferation, and morphology are highly affected by lithium. We demonstrate that members of several signaling pathways are activated by lithium treatment, including the PKB/Akt-kinase and the mitogen-activated protein kinases (MAPK), such as extracellular regulated kinase (ERK), c-Jun NH2-terminal kinase (JNK), and p38. Lithium treatment increased the intracellular accumulation of β-catenin in association with increased levels of phosphorylated glycogen synthase kinase type 3β (GSK3β). This study provides a comprehensive analysis of the proteins affected by lithium treatment in the IMCD and, as such, provides clues to potential lithium targets in the brain. PMID:18296634

  8. Short-term administration of rhGH increases markers of cellular proliferation but not milk protein gene expression in normal lactating women

    PubMed Central

    Maningat, Patricia D.; Sen, Partha; Rijnkels, Monique; Hadsell, Darryl L.; Bray, Molly S.

    2011-01-01

    Growth hormone is one of few pharmacologic agents known to augment milk production in humans. We hypothesized that recombinant human GH (rhGH) increases the expression of cell proliferation and milk protein synthesis genes. Sequential milk and blood samples collected over four days were obtained from five normal lactating women. Following 24 h of baseline milk and blood sampling, rhGH (0.1 mg/kg/day) was administered subcutaneously once daily for 3 days. Gene expression changes were determined by microarray studies utilizing milk fat globule RNA isolated from each milk sample. Following rhGH administration, DNA synthesis and cell cycle genes were induced, while no significant changes were observed in the expression of milk synthesis genes. Expression of glycolysis and citric acid cycle genes were increased by day 4 compared with day 1, while lipid synthesis genes displayed a circadian-like pattern. Cell cycle gene upregulation occurred after a lag of ∼2 days, likely explaining the failure to increase milk production after only 3 days of rhGH treatment. We conclude that rhGH induces expression of cellular proliferation and metabolism genes but does not induce milk protein gene expression, as potential mechanisms for increasing milk production and could account for the known effect of rhGH to increase milk production following 7–10 days. PMID:21205870

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

    PubMed

    Almeida, Luciana O; Garcia, Cristiana B; Matos-Silva, Flavia A; Curti, Carlos; Leopoldino, Andréia M

    2014-02-28

    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.

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

    SciTech Connect

    Almeida, Luciana O.; Garcia, Cristiana B.; Matos-Silva, Flavia A.; Curti, Carlos; Leopoldino, Andréia M.

    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.

  11. Hominis Placenta facilitates hair re-growth by upregulating cellular proliferation and expression of fibroblast growth factor-7.

    PubMed

    Seo, Hyung-Sik; Lee, Dong-Jin; Chung, Jae-Ho; Lee, Chang-Hyun; Kim, Ha Rim; Kim, Jae Eun; Kim, Byung Joo; Jung, Myeong Ho; Ha, Ki-Tae; Jeong, Han-Sol

    2016-07-07

    Hominis Placenta (HP) known as a restorative medicine in Traditional Chinese Medicine (TCM), has been widely applied in the clinics of Korea and China as an anti-aging agent to enhance the regeneration of tissue. This study was conducted to investigate whether topical treatment of HP promotes hair regrowth in the animal model. The dorsal hairs of 8-week-old C57BL/6 mice were depilated to synchronize hair follicles to the anagen phase. HP was applied topically once a day for 15 days. Hair growth was evaluated visually and microscopically. The incorporation of bromodeoxyuridine (BrdU) and expression of proliferating cell nuclear antigen (PCNA), fibroblast growth factor-7 (FGF-7) in dorsal skin tissue was examined by immunohistochemical analysis. Reverse transcription polymerase chain reaction (RT-PCR) was used to measure the mRNA expression of FGF-7. HP exhibited potent hair growth-promoting activity in C57BL/6 mice. Gross examination indicated that HP markedly increased hair regrowth as well as hair density and diameter. Histologic analysis showed that HP treatment enhanced the anagen induction of hair follicles. Immunohistochemical analysis revealed that BrdU incorporation and the expressions of PCNA were increased by treatment of HP. HP treatment significantly increased the expression of FGF-7, which plays pivotal roles to maintain anagen phase both protein and mRNA levels. Taken together, our results indicate that HP has a potent hair growth-promoting activity; therefore, it may be a good candidate for the treatment of alopecia.

  12. Pyruvate Dehydrogenase Kinase 4 Deficiency Results in Expedited Cellular Proliferation through E2F1-Mediated Increase of Cyclins.

    PubMed

    Choiniere, Jonathan; Wu, Jianguo; Wang, Li

    2017-03-01

    Hepatocellular carcinoma (HCC) is a common form of cancer with prevalence worldwide. There are many factors that lead to the development and progression of HCC. This study aimed to identify potential new tumor suppressors, examine their function as cell cycle modulators, and investigate their impact on the cyclin family of proteins and cyclin-dependent kinases (CDKs). In this study, the pyruvate dehydrogenase kinase (PDK)4 gene was shown to have potential tumor suppressor characteristics. PDK4 expression was significantly downregulated in human HCC. Pdk4(-/-) mouse liver exhibited a consistent increase in cell cycle regulator proteins, including cyclin D1, cyclin E1, cyclin A2, some associated CDKs, and transcription factor E2F1. PDK4-knockdown HCC cells also progressed faster through the cell cycle, which concurrently expressed high levels of cyclins and E2F1 as seen in the Pdk4(-/-) mice. Interestingly, the induced cyclin E1 and cyclin A2 caused by Pdk4 deficiency was repressed by arsenic treatment in mouse liver and in HCC cells. E2f1 deficiency in E2f1(-/-) mouse liver or knockdown E2F1 using small hairpin RNAs in HCC cells significantly decreased cyclin E1, cyclin A2, and E2F1 proteins. In contrast, inhibition of PDK4 activity in HCC cells increased cyclin E1, cyclin A2, and E2F1 proteins. These findings demonstrate that PDK4 is a critical regulator of hepatocyte proliferation via E2F1-mediated regulation of cyclins. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

  13. Tenocytic extract and mechanical stimulation in a tissue-engineered tendon construct increases cellular proliferation and ECM deposition.

    PubMed

    Engebretson, Brandon; Mussett, Zachary R; Sikavitsas, Vassilios I

    2017-03-01

    Chemical and mechanical stimulation, when properly utilized, positively influence both the differentiation of in vitro cultured stem cells and the quality of the deposited extracellular matrix (ECM). This study aimed to find if cell-free extract from primary tenocytes can positively affect the development of a tissue-engineered tendon construct, consisting of a human umbilical vein (HUV) seeded with mesenchymal stem cells (MSCs) subjected to cyclical mechanical stimulation. The tenocytic cell-free extract possesses biological material from tendon cells that could potentially influence MSC tenocytic differentiation and construct development. We demonstrate that the addition of tenocytic extract in statically cultured tendon constructs increases ECM deposition and tendon-related gene expression of MSCs. The incorporation of mechanical stimulation (2% strain for 30 min/day at 0.5 cycles/min) with tenocytic extract further improved the MSC seeded HUV constructs by increasing cellularity of the construct by 37% and the ultimate tensile strength by 33% compared to the constructs with only mechanical stimulation after 14 days. Furthermore, the addition of mechanical stimulation to the extract supplementation produced longitudinal ECM fibril alignment along with dense connective tissue, reminiscent of natural tendon. Copyright © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. A chimera embryo assay reveals a decrease in embryonic cellular proliferation induced by sperm from X-irradiated male mice

    SciTech Connect

    Obasaju, M.F.; Wiley, L.M.; Oudiz, D.J.; Raabe, O.; Overstreet, J.W.

    1989-05-01

    Male mice were divided into three experimental groups and a control group. Mice in the experimental groups received one of three doses of acute X irradiation (1.73, 0.29, and 0.05 Gy) and together with the control unirradiated mice were then mated weekly to unirradiated female mice for a 9-week experimental period. Embryos were recovered from the weekly matings at the four-cell stage and examined by the chimera assay for proliferative disadvantage. Aggregation chimeras were constructed of embryos from female mice mated to irradiated males (experimental embryos) and embryos from females mated to unexposed males (control embryos) and contained either one experimental embryo and one control embryo (heterologous chimera) or two control embryos (control chimera). The control embryo in heterologous chimeras and either embryo in control chimeras were prelabeled with the vital dye fluorescein isothiocyanate (FITC), and the chimeras were cultured for 40 h and viewed under phase-contrast and epifluorescence microscopy to obtain total embryo cell number and the cellular contribution from the FITC-labeled embryo. Experimental and control embryos that were cultured singly were also examined for embryo cell number at the end of the 40-h culture period. In control chimeras, the mean ratio of the unlabeled cells:total chimera cell number (henceforth referred to as ''mean ratio'') was 0.50 with little or no weekly variation over the 9-week experimental period. During Weeks 4-7, the mean ratios of heterologous chimeras differed significantly from the mean ratio of control chimeras with the greatest differences occurring during Week 7 (0.41 for chimeras of 0.05 Gy dose group, 0.40 for chimeras of the 0.29 Gy dose group, and 0.17 for chimeras of the 1.73 Gy dose group).

  15. Recurrence rate, clinical outcome, and cellular proliferation indices as prognostic indicators after incomplete surgical excision of cutaneous grade II mast cell tumors: 28 dogs (1994-2002).

    PubMed

    Séguin, Bernard; Besancon, M Faulkner; McCallan, Jennifer L; Dewe, Loralei L; Tenwolde, Matthew C; Wong, Emily K; Kent, Michael S

    2006-01-01

    The objectives of this study were to determine local recurrence rate, clinical outcome, and prognostic value of the number of argyrophylic nucleolar organizer regions (AgNORs), presence of proliferating cell nuclear antigen (PCNA), and number of Ki-67-positive nuclei after incomplete surgical excision of canine cutaneous grade II mast cell tumors (MCTs). This retrospective study included 30 MCTs in 28 dogs. Medical records were examined and follow-up information was obtained from owners and referring veterinarians. Only cases in which excision was incomplete and no anvcillary therapy (other than prednisone) for MCT was given were included. Paraffin-embedded tumor tissues were retrieved for AgNORs, PCNA, and Ki-67 staining. Median follow-up time was 811.5 days. Seven (23.3%) tumors recurred locally. Median time to local recurrence was not reached with a mean of 1,713 days. The estimated proportions of tumors that recurred locally at 1, 2, and 5 years were 17.3, 22.1, and 33.3%, respectively. Eleven (39.3%) dogs developed MCTs at other cutaneous locations. Median progression-free survival was 1,044 days. Median overall survival was 1,426 days. The combination of Ki-67 and PCNA scores was prognostic for local recurrence (P = .03) and development of local recurrence was prognostic for decreased overall survival (P = .04). Results suggest that a minority of incompletely excised MCTs recur. Therefore, ancillary local therapies may not always be necessary. However, local recurrence can negatively affect survival of the affected dogs. Cellular proliferation indices may indicate the likelihood of MCT recurrence after incomplete excision.

  16. Recovery of cellular E-cadherin precedes replenishment of estrogen receptor and estrogen-dependent proliferation of breast cancer cells rescued from a death stimulus.

    PubMed

    Malaguti, Claudia; Rossini, Gian Paolo

    2002-08-01

    Loss of estrogen-responsiveness and impaired E-cadherin expression/function has been linked to increased metastatic potential of breast cancer cells. In this study, we report that proliferation of breast cancer cells can resume following removal of a toxic stimulus causing severe impairment of cell adhesion and estrogen responsiveness. This type of response was induced by okadaic acid (OA) in MCF-7 cells, and was accompanied by an almost complete block of DNA synthesis, loss of cell-cell contact and cell detachment from culture dishes, loss of estrogen receptor (ER), progesterone receptor (PR) and E-cadherin, whereas only a weak, if any, inhibition of protein synthesis could be observed. These responses were detected in MCF-7 cells after a 1-day treatment with 50 nM OA, and could be reversed if OA-treated cells were recovered in a culture medium devoid of the toxin, so that rescued cells resumed growth 8-12 days after replating. By pulse-chase experiments, we found that protein synthesis was not significantly affected in rescued cells, whose DNA synthesis, instead, was almost completely blocked during the first days of MCF-7 cell rescue from OA treatment. We also analyzed E-cadherin, mitogen activated protein kinase isoforms ERK1 and ERK2, Bcl-2 and BAX proteins during the rescue of MCF-7 cells from OA-induced cell death, and found that their expression followed temporally defined patterns. Cellular levels of E-cadherin returned to control levels within the first days of the rescue, followed by ER, ERK1, and ERK2, and finally by Bcl-2 and BAX proteins. Under our experimental conditions, restoration of cell adhesion did not require a functional ER system, but recovery of a normal ER pool accompanied resumption of estrogen-dependent proliferation of OA-treated MCF-7 cells.

  17. Effects of iron and copper overload on the human liver: an ultrastructural study.

    PubMed

    Fanni, D; Fanos, V; Gerosa, C; Piras, M; Dessi, A; Atzei, A; Van, Eyken P; Gibo, Y; Faa, G

    2014-01-01

    Iron and copper ions play important roles in many physiological functions of our body, even though the exact mechanisms regulating their absorption, distribution and excretion are not fully understood. Metal-related human pathology may be observed in two different clinical settings: deficiency or overload. The overload in liver cells of both trace elements leads to multiple cellular lesions. Here we report the main pathological changes observed at transmission electron microscopy in the liver of subjects affected by Beta-thalassemia and by Wilson's disease. The hepatic iron overload in beta-thalassemia patients is associated with haemosiderin storage both in Kupffer cells and in the cytoplasm of hepatocytes. Haemosiderin granules are grouped inside voluminous lysosomes, also called siderosomes. Other ultrastructural changes are fat droplets, proliferation of the smooth endoplasmic reticulum and fibrosis. Apoptosis of hepatocytes and infiltration of sinusoids by polymorphonucleates is also detected in beta-thalassemia. Ultrastructural changes in liver biopsies from Wilson's disease patients are characterized by severe mitochondrial changes, associated with an increased number of perossisomes, cytoplasmic lipid droplets and the presence of lipolysosomes, characteristic cytoplasmic bodies formed by lipid vacuoles surrounded by electron-dense lysosomes. In patients affected by Wilson's disease, nuclei are frequently involved, with disorganization of the nucleoplasm and with glycogen inclusions. On the contrary, no significant changes are detected in Kupffer cells. Our data show that iron and copper, even though are both transition metals, are responsible of different pathological changes at ultrastructural level. In particular, copper overload is associated with mitochondrial damage, whereas iron overload only rarely may cause severe mitochondrial changes. These differences underlay the need for further studies in which biochemical analyses should be associated with

  18. Epstein-Barr virus nuclear antigen 3A promotes cellular proliferation by repression of the cyclin-dependent kinase inhibitor p21WAF1/CIP1.

    PubMed

    Tursiella, Melissa L; Bowman, Emily R; Wanzeck, Keith C; Throm, Robert E; Liao, Jason; Zhu, Junjia; Sample, Clare E

    2014-10-01

    Latent infection by Epstein-Barr virus (EBV) is highly associated with the endemic form of Burkitt lymphoma (eBL), which typically limits expression of EBV proteins to EBNA-1 (Latency I). Interestingly, a subset of eBLs maintain a variant program of EBV latency - Wp-restricted latency (Wp-R) - that includes expression of the EBNA-3 proteins (3A, 3B and 3C), in addition to EBNA-1. In xenograft assays, Wp-R BL cell lines were notably more tumorigenic than their counterparts that maintain Latency I, suggesting that the additional latency-associated proteins expressed in Wp-R influence cell proliferation and/or survival. Here, we evaluated the contribution of EBNA-3A. Consistent with the enhanced tumorigenic potential of Wp-R BLs, knockdown of EBNA-3A expression resulted in abrupt cell-cycle arrest in G0/G1 that was concomitant with conversion of retinoblastoma protein (Rb) to its hypophosphorylated state, followed by a loss of Rb protein. Comparable results were seen in EBV-immortalized B lymphoblastoid cell lines (LCLs), consistent with the previous observation that EBNA-3A is essential for sustained growth of these cells. In agreement with the known ability of EBNA-3A and EBNA-3C to cooperatively repress p14(ARF) and p16(INK4a) expression, knockdown of EBNA-3A in LCLs resulted in rapid elevation of p14(ARF) and p16I(NK4a). By contrast, p16(INK4a) was not detectably expressed in Wp-R BL and the low-level expression of p14(ARF) was unchanged by EBNA-3A knockdown. Amongst other G1/S regulatory proteins, only p21(WAF1/CIP1), a potent inducer of G1 arrest, was upregulated following knockdown of EBNA-3A in Wp-R BL Sal cells and LCLs, coincident with hypophosphorylation and destabilization of Rb and growth arrest. Furthermore, knockdown of p21(WAF1/CIP1) expression in Wp-R BL correlated with an increase in cellular proliferation. This novel function of EBNA-3A is distinct from the functions previously described that are shared with EBNA-3C, and likely contributes to the

  19. Epstein-Barr Virus Nuclear Antigen 3A Promotes Cellular Proliferation by Repression of the Cyclin-Dependent Kinase Inhibitor p21WAF1/CIP1

    PubMed Central

    Tursiella, Melissa L.; Bowman, Emily R.; Wanzeck, Keith C.; Throm, Robert E.; Liao, Jason; Zhu, Junjia; Sample, Clare E.

    2014-01-01

    Latent infection by Epstein-Barr virus (EBV) is highly associated with the endemic form of Burkitt lymphoma (eBL), which typically limits expression of EBV proteins to EBNA-1 (Latency I). Interestingly, a subset of eBLs maintain a variant program of EBV latency - Wp-restricted latency (Wp-R) - that includes expression of the EBNA-3 proteins (3A, 3B and 3C), in addition to EBNA-1. In xenograft assays, Wp-R BL cell lines were notably more tumorigenic than their counterparts that maintain Latency I, suggesting that the additional latency-associated proteins expressed in Wp-R influence cell proliferation and/or survival. Here, we evaluated the contribution of EBNA-3A. Consistent with the enhanced tumorigenic potential of Wp-R BLs, knockdown of EBNA-3A expression resulted in abrupt cell-cycle arrest in G0/G1 that was concomitant with conversion of retinoblastoma protein (Rb) to its hypophosphorylated state, followed by a loss of Rb protein. Comparable results were seen in EBV-immortalized B lymphoblastoid cell lines (LCLs), consistent with the previous observation that EBNA-3A is essential for sustained growth of these cells. In agreement with the known ability of EBNA-3A and EBNA-3C to cooperatively repress p14ARF and p16INK4a expression, knockdown of EBNA-3A in LCLs resulted in rapid elevation of p14ARF and p16INK4a. By contrast, p16INK4a was not detectably expressed in Wp-R BL and the low-level expression of p14ARF was unchanged by EBNA-3A knockdown. Amongst other G1/S regulatory proteins, only p21WAF1/CIP1, a potent inducer of G1 arrest, was upregulated following knockdown of EBNA-3A in Wp-R BL Sal cells and LCLs, coincident with hypophosphorylation and destabilization of Rb and growth arrest. Furthermore, knockdown of p21WAF1/CIP1 expression in Wp-R BL correlated with an increase in cellular proliferation. This novel function of EBNA-3A is distinct from the functions previously described that are shared with EBNA-3C, and likely contributes to the proliferation of

  20. A Novel Interaction between FLICE-Associated Huge Protein (FLASH) and E2A Regulates Cell Proliferation and Cellular Senescence via Tumor Necrosis Factor (TNF)-Alpha-p21WAF1/CIP1 Axis

    PubMed Central

    Hirano, Takahiro; Murakami, Taichi; Ono, Hiroyuki; Sakurai, Akiko; Tominaga, Tatsuya; Takahashi, Toshikazu; Nagai, Kojiro; Doi, Toshio; Abe, Hideharu

    2015-01-01

    Dysregulation of the cell proliferation has been implicated in the pathophysiology of a number of diseases. Cellular senescence limits proliferation of cancer cells, preventing tumorigenesis and restricting tissue damage. However, the role of cellular senescence in proliferative nephritis has not been determined. The proliferative peak in experimental rat nephritis coincided with a peak in E2A expression in the glomeruli. Meanwhile, E12 (an E2A-encoded transcription factor) did not promote proliferation of Mesangial cells (MCs) by itself. We identified caspase-8-binding protein FLICE-associated huge protein (FLASH) as a novel E2A-binding partner by using a yeast two-hybrid screening. Knockdown of FLASH suppressed proliferation of MCs. This inhibitory effect was partially reversed by the knockdown of E2A. In addition, the knockdown of FLASH induced cyclin-dependent kinase inhibitor p21WAF1/CIP1 (p21) expression, but did not affect p53 expression. Furthermore, overexpression of E12 and E47 induced p21, but not p53 in MCs, in the absence of FLASH. We also demonstrated that E2A and p21 expression at the peak of proliferation was followed by significant induction of FLASH in mesangial areas in rat proliferative glomerulonephritis. Moreover, we revealed that FLASH negatively regulates cellular senescence via the interaction with E12. We also demonstrated that FLASH is involved in the TNF-α-induced p21 expressions. These results suggest that the functional interaction of E2A and FLASH play an important role in cell proliferation and cellular senescence via regulation of p21 expression in experimental glomerulonephritis. PMID:26208142

  1. A Novel Interaction between FLICE-Associated Huge Protein (FLASH) and E2A Regulates Cell Proliferation and Cellular Senescence via Tumor Necrosis Factor (TNF)-Alpha-p21WAF1/CIP1 Axis.

    PubMed

    Hirano, Takahiro; Murakami, Taichi; Ono, Hiroyuki; Sakurai, Akiko; Tominaga, Tatsuya; Takahashi, Toshikazu; Nagai, Kojiro; Doi, Toshio; Abe, Hideharu

    2015-01-01

    Dysregulation of the cell proliferation has been implicated in the pathophysiology of a number of diseases. Cellular senescence limits proliferation of cancer cells, preventing tumorigenesis and restricting tissue damage. However, the role of cellular senescence in proliferative nephritis has not been determined. The proliferative peak in experimental rat nephritis coincided with a peak in E2A expression in the glomeruli. Meanwhile, E12 (an E2A-encoded transcription factor) did not promote proliferation of Mesangial cells (MCs) by itself. We identified caspase-8-binding protein FLICE-associated huge protein (FLASH) as a novel E2A-binding partner by using a yeast two-hybrid screening. Knockdown of FLASH suppressed proliferation of MCs. This inhibitory effect was partially reversed by the knockdown of E2A. In addition, the knockdown of FLASH induced cyclin-dependent kinase inhibitor p21WAF1/CIP1 (p21) expression, but did not affect p53 expression. Furthermore, overexpression of E12 and E47 induced p21, but not p53 in MCs, in the absence of FLASH. We also demonstrated that E2A and p21 expression at the peak of proliferation was followed by significant induction of FLASH in mesangial areas in rat proliferative glomerulonephritis. Moreover, we revealed that FLASH negatively regulates cellular senescence via the interaction with E12. We also demonstrated that FLASH is involved in the TNF-α-induced p21 expressions. These results suggest that the functional interaction of E2A and FLASH play an important role in cell proliferation and cellular senescence via regulation of p21 expression in experimental glomerulonephritis.

  2. Cellular proliferation and cytokine responses of murine macrophage cell line J774A.1 to polymethylmethacrylate and cobalt-chrome alloy particles.

    PubMed

    Prabhu, A; Shelburne, C E; Gibbons, D F

    1998-12-15

    Wear debris from orthopedic joint implants have been postulated to initiate a cascade of complex cellular events that results in aseptic loosening of the prosthesis and eventually in loss of function of the device. The impact of biomaterials used in these devices on host inflammatory response has not been examined extensively. Polymethylmethacrylate (PMMA) and cobalt-chrome alloy (CoCr) are biomaterials widely used in orthopedic implant devices. Macrophages are an important component of the host inflammatory response, and we have examined the effect of PMMA and CoCr particles on the murine macrophage cell line J774A.1. Our objective was to obtain a comprehensive analysis of the particle-macrophage interaction, and we examined a number of basic biological responses of the J774A.1 cell line, including cell proliferation, apoptosis, cytokines secreted into the culture supernatant (TNFalpha, IL-1alpha, IL-6, and IL-12) and mRNA expression of the cytokines (TNFalpha, IL-1alpha, IL-6, IFN-alpha, M-CSF, and TGF-beta) in response to PMMA and CoCr particles. Our results indicate that the relative contribution of PMMA and CoCr particles in J774A.1 activation is negligible, and we observed a change in metabolic activity of J774A.1 cells only at higher concentrations of CoCr particles.

  3. Real-time proliferation of porcine cumulus cells is related to the protein levels and cellular distribution of Cdk4 and Cx43.

    PubMed

    Kempisty, Bartosz; Ziółkowska, Agnieszka; Piotrowska, Hanna; Zawierucha, Piotr; Antosik, Paweł; Bukowska, Dorota; Ciesiółka, Sylwia; Jaśkowski, Jędrzej M; Brüssow, Klaus P; Nowicki, Michał; Zabel, Maciej

    2013-09-01

    The proper maturation of cumulus somatic cells depends on bidirectional communication between the oocyte and the surrounding cumulus cells (CCs). The aim of this study was (i) to investigate maturation markers, such as Cx43 and Cdk4 protein levels, and (ii) to analyze the distribution of these two proteins in CCs cultured for 44, 88, 132, and 164 hours in both separated and cumulus-enclosed oocyte cultures. CCs were isolated from porcine ovarian follicles after the treatment of the recovered COCs with collagenase. Then, the separated CCs were cultured in TCM-199 for 0 to 164 hours, using a real-time cellular analyzer; however, the immunostaining was performed only after 44, 88, and 132 hours. The protein levels and distribution were analyzed using confocal microscopy. After the CCs underwent in vitro cultivation (IVC) for 25 hours, a logarithmically increasing normalized proliferation index was found throughout the entire 164 hours cultivation time. The Cx43 and Cdk4 proteins were observed at higher levels after 44 hours of culture than before IVC. After 88 and 132 hours of IVC, no significant alterations in either mRNA or protein levels of Cx43 and Cdk4 were found. Cx43 and Cdk4 were localized in the cell nucleus before IVC, whereas after 44, 88, and 132 hours of IVC, both proteins translocated to the cytoplasm. In cumulus-enclosed oocyte cultures, Cdk4 was localized both in the nucleus and cytoplasm, whereas Cx43 was only in the cytoplasm. Additionally, only low levels of the cumulus expansion markers MIS and SNAT3 were observed. In summary, we could demonstrate that the in vitro cultivation of CCs was associated with cell proliferation and that Cx43 and Cdk4 gene expression was upregulated after IVC, resulting in significantly higher protein levels. Moreover, the two proteins translocated from the nucleus to the cytoplasm of the CCs during IVC. The protein distribution is presumably related to different protein functions during bidirectional communication via

  4. Species-specific control of cellular proliferation and the impact of large animal models for the use of olfactory ensheathing cells and Schwann cells in spinal cord repair.

    PubMed

    Wewetzer, Konstantin; Radtke, Christine; Kocsis, Jeffery; Baumgärtner, Wolfgang

    2011-05-01

    Autologous transplantation of olfactory ensheathing cells (OECs) and Schwann cells (SCs) is considered a promising option to promote axonal regrowth and remyelination after spinal cord injury in humans. However, if the experimental data from the rodent model can be directly extrapolated to humans, as widely believed, remains to be established. While limitations of the rodent system have recently been discussed with regard to the distinct organization of the motor systems, the question whether OECs and SCs may display species-specific properties has not been fully addressed. Prompted by recent studies on canine and porcine glia, we performed a detailed analysis of the in vitro and in vivo properties of OECs and SCs and show that rodent but not human, monkey, porcine, and canine glia require mitogens for in vitro expansion, display a complex response to elevated intracellular cAMP, and undergo spontaneous immortalization upon prolonged mitogen stimulation. These data indicate fundamental inter-species differences of the control of cellular proliferation. Whether OECs and SCs from large animals and humans share growth-promoting in vivo properties with their rodent counterpart is not yet clear. Autologous implantation studies in humans did not reveal adverse effects of cell transplantation so far. However, in vivo studies of large animal or human glia and rodent recipients mainly focused on the remyelinating potential of the transplanted cells. Thus, further experimental in vivo studies in large animals are essential to fully define the axonal growth-promoting potential of OECs and SCs. Based on the homology of the in vitro growth control between porcine, canine and human glia, it is concluded that these species may serve as valuable translational models for scaling up human procedures. This article is part of a Special Issue entitled: Understanding olfactory ensheathing glia and their prospect for nervous system repair. Copyright © 2010 Elsevier Inc. All rights

  5. Effect of prolotherapy on cellular proliferation and collagen deposition in MC3T3-E1 and patellar tendon fibroblast populations.

    PubMed

    Freeman, Joseph W; Empson, Yvonne M; Ekwueme, Emmanuel C; Paynter, Danielle M; Brolinson, P Gunnar

    2011-09-01

    Proliferative therapy, or prolotherapy, is a treatment for damaged connective tissues involving the injection of a solution (proliferant) which causes local cell death and triggers the body's wound healing cascade. Physicians vary in their use of this technique; it is employed for ligaments but has also been investigated for tissues such as cartilage. Physicians also vary in treatment regiments using different dosses of the proliferant. This study evaluates several proliferant dosages develop an optimal dosage that maximizes cell and collagen regeneration. This study also looks at cell and collagen regeneration in response to proliferant exposure outside of the healing cascade. MC3T3-E1 cells and patellar tendon fibroblasts were exposed to various amounts of the proliferant P2G and monitored over several weeks. The results showed an inverse relationship between proliferant concentration and cell viability and collagen production in MC3T3-E1 cells. Following exposure, cell populations experienced an initial decrease in cell number followed by increased proliferation. Trichrome staining over 4 weeks showed an increase in collagen production after proliferant exposure. However the cell numbers and amounts of collagen from the treated groups never surpassed those of the untreated groups, although collagen production was comparable in fibroblasts. The results of this basic study show that there is an effective proliferant dosage and point to a local response to the proliferant that increases cell proliferation and collagen production separate from the wound healing cascade. This local response may not be adequate for complete healing and assistance from the body's healing cascade may be required. Published by Mosby, Inc.

  6. Pediatric non-alcoholic steatohepatitis: the first report on the ultrastructure of hepatocyte mitochondria.

    PubMed

    Lotowska, Joanna M; Sobaniec-Lotowska, Maria E; Bockowska, Sylwia B; Lebensztejn, Dariusz M

    2014-04-21

    To investigate the ultrastructure of abnormal hepatocyte mitochondria, including their cellular and hepatic zonal distribution, in bioptates in pediatric non-alcoholic steatohepatitis (NASH). Ultrastructural investigations were conducted on biopsy liver specimens obtained from 10 children (6 boys and 4 girls) aged 2-14 years with previously clinicopathologically diagnosed NASH. The disease was diagnosed if liver biopsy revealed steatosis, inflammation, ballooned hepatocytes, Mallory hyaline, or focal necrosis, varying degrees of fibrosis in the absence of clinical, serological, or histological findings of infectious liver diseases, autoimmune hepatitis, metabolic liver diseases, or celiac disease. For ultrastructural analysis, fresh small liver blocks (1 mm(3) volume) were fixed in a solution containing 2% paraformaldehyde and 2.5% glutaraldehyde in 0.1 mol/L cacodylate buffer. The specimens were postfixed in osmium tetroxide, subsequently dehydrated through a graded series of ethanols and propylene oxide, and embedded in Epon 812. The material was sectioned on a Reichert ultramicrotome to obtain semithin sections, which were stained with methylene blue in sodium borate. Ultrathin sections were contrasted with uranyl acetate and lead citrate, and examined using an Opton EM 900 transmission electron microscope. Ultrastructural analysis of bioptates obtained from children with non-alcoholic steatohepatitis revealed characteristic repetitive mitochondrial abnormalities within hepatocytes; mainly mitochondrial polymorphisms such as megamitochondria, loss of mitochondrial cristae, and the presence of linear crystalline inclusions within the mitochondrial matrix of an increased electron density. The crystalline inclusions were particularly evident within megamitochondria (MMC), which seemed to be distributed randomly both within the hepatic parenchymal cell and the zones of hepatic lobule, without special variations in abundance. The inclusions appeared as bundles viewed

  7. Pediatric non-alcoholic steatohepatitis: The first report on the ultrastructure of hepatocyte mitochondria

    PubMed Central

    Lotowska, Joanna M; Sobaniec-Lotowska, Maria E; Bockowska, Sylwia B; Lebensztejn, Dariusz M

    2014-01-01

    AIM: To investigate the ultrastructure of abnormal hepatocyte mitochondria, including their cellular and hepatic zonal distribution, in bioptates in pediatric non-alcoholic steatohepatitis (NASH). METHODS: Ultrastructural investigations were conducted on biopsy liver specimens obtained from 10 children (6 boys and 4 girls) aged 2-14 years with previously clinicopathologically diagnosed NASH. The disease was diagnosed if liver biopsy revealed steatosis, inflammation, ballooned hepatocytes, Mallory hyaline, or focal necrosis, varying degrees of fibrosis in the absence of clinical, serological, or histological findings of infectious liver diseases, autoimmune hepatitis, metabolic liver diseases, or celiac disease. For ultrastructural analysis, fresh small liver blocks (1 mm3 volume) were fixed in a solution containing 2% paraformaldehyde and 2.5% glutaraldehyde in 0.1 mol/L cacodylate buffer. The specimens were postfixed in osmium tetroxide, subsequently dehydrated through a graded series of ethanols and propylene oxide, and embedded in Epon 812. The material was sectioned on a Reichert ultramicrotome to obtain semithin sections, which were stained with methylene blue in sodium borate. Ultrathin sections were contrasted with uranyl acetate and lead citrate, and examined using an Opton EM 900 transmission electron microscope. RESULTS: Ultrastructural analysis of bioptates obtained from children with non-alcoholic steatohepatitis revealed characteristic repetitive mitochondrial abnormalities within hepatocytes; mainly mitochondrial polymorphisms such as megamitochondria, loss of mitochondrial cristae, and the presence of linear crystalline inclusions within the mitochondrial matrix of an increased electron density. The crystalline inclusions were particularly evident within megamitochondria (MMC), which seemed to be distributed randomly both within the hepatic parenchymal cell and the zones of hepatic lobule, without special variations in abundance. The inclusions

  8. Cellular changes in the hamster testicular interstitium with ageing and after exposure to short photoperiod.

    PubMed

    Beltrán-Frutos, E; Seco-Rovira, V; Ferrer, C; Madrid, J F; Sáez, F J; Canteras, M; Pastor, L M

    2016-04-01

    The aim of this study was to evaluate the cellular changes that occur in the hamster testicular interstitium in two very different physiological situations involving testicular involution: ageing and exposure to a short photoperiod. The animals were divided into an 'age group' with three subgroups - young, adult and old animals - and a 'regressed group' with animals subjected to a short photoperiod. The testicular interstitium was characterised by light and electron microscopy. Interstitial cells were studied histochemically with regard to their proliferation, terminal deoxynucleotidyl transferase (TdT)-mediated dUTP in situ nick end labelling (TUNEL+) and testosterone synthetic activity. We identified two types of Leydig cell: Type A cells showed a normal morphology, while Type B cells appeared necrotic. With ageing, pericyte proliferation decreased but there was no variation in the index of TUNEL-positive Leydig cells. In the regressed group, pericyte proliferation was greater and TUNEL-positive cells were not observed in the interstitium. The testicular interstitium suffered few ultrastructural changes during ageing and necrotic Leydig cells were observed. In contrast, an ultrastructural involution of Leydig cells with no necrosis was observed in the regressed group. In conclusion, the testicular interstitium of Mesocricetus auratus showed different cellular changes in the two groups (age and regressed), probably due to the irreversible nature of ageing and the reversible character of changes induced by short photoperiod.

  9. Ultrastructural study of thyroid capillaries after IR laser radiation

    NASA Astrophysics Data System (ADS)

    Vidal, Lourdes; Perez de Vargas, I.; Carrillo, F.; Parrado, C.; Pelaez, A.

    1994-02-01

    Laser radiation causes microscopical changes in the follicular cells relative to dose intensity. So, we have observed focal degenerative phenomena, at maximal doses, and activation of cellular function similar to the ones observed after stimulation with TSH, at minimal doses. In order to evaluate the evolution of these changes we have planned an ultrastructural study of rats thyroid capillaries treated with IR laser radiation.

  10. Antenatal taurine supplementation for improving brain ultrastructure in fetal rats with intrauterine growth restriction.

    PubMed

    Liu, J; Liu, L; Chen, H

    2011-05-05

    Changes in brain ultrastructure of fetal rats with intrauterine growth restriction (IUGR) were explored and the effects of antenatal taurine supplementation on their brain ultrastructure were determined. Fifteen pregnant rats were randomly divided into three groups: control group, IUGR model group and IUGR group given antenatal taurine supplements. Taurine was added to the diet of the taurine group at a dose of 300 mg/kg/d from 12 days after conception until natural delivery. Transmission electron microscopy was used to observe ultrastructural changes in the brains of the newborn rats. At the same time, brain cellular apoptosis was detected using TUNEL, and the changes in protein expression of neuron specific enolase and glial fibrillary acidic protein were analyzed using immunohistochemistry. The results showed that: 1) The average body weight and cerebral weight were significantly lower in the IUGR group than in the control group (p<0.01) and both of them were less so after taurine was supplemented (p<0.01). 2) Transmission electron microscopy revealed that brain cortex structures were sparse IUGR rats, showing many scattered apoptotic cells, decreased numbers of synapses, lower glial cell proliferation, and fewer neurons, more sparsely arranged, while these factors were significantly improved with taurine supplementation. 3) The results of TUNEL showed that the counts of apoptotic brain cells in IUGR groups were significantly increased from those in control groups and that taurine could significantly decrease brain cell apoptosis (p<0.001). 4) The results of immunohistochemistry showed that antenatal taurine-supplementation could significantly increase the counts of neuron specific enolase and glial fibrillary acidic protein immunoreactive cells in fetal rats with IUGR (p<0.001). It can be concluded that it IUGR has a significant detrimental influence on the development of fetal rat brains, and antenatal supplement of taurine can significantly improve the IUGR

  11. Relationship of carcinogenicity and cellular proliferation induced by mutagenic noncarcinogens vs carcinogens. III. Organophosphate pesticides vs tris(2,3-dibromopropyl)phosphate.

    PubMed

    Cunningham, M L; Elwell, M R; Matthews, H B

    1994-10-01

    Our laboratory has been examining the mechanisms whereby chemicals produce mutagenicity in short-term in vitro assays yet fail to produce carcinogenesis in 2-year rodent bioassays. Previous studies indicated that some mutagenic hepatocarcinogens increased cell proliferation in the target organ, the liver, while other structurally related mutagens that were noncarcinogenic failed to do so. We demonstrate in this report that another mutagenic carcinogen, tris(2,3-dibromopropyl phosphate), increased cell proliferation that was localized in the outer medulla of the kidney. This was also the target site for carcinogenesis in a 2-year bioassay and is another example of the association between chemically induced cell proliferation and carcinogenesis. This study also reports the absence of increased cell proliferation in the liver or kidney after exposure in the diet to the mutagenic organophosphate insecticides dimethoate, dioxathion, and dichlorvos following dietary exposure for 2 weeks at the same dose levels and routes of exposure that did not increase the tumor incidence in either organ in 2-year carcinogenesis assays. The present studies support the tenet that chemically induced cell proliferation may be a necessary prerequisite for chemical carcinogenesis, since in rat liver and kidney there was neither cell proliferation after 2 weeks nor tumor development after 2 years dietary exposure to the mutagenic organophosphate insecticides dimethoate, dioxathion, and dichlorvos.

  12. Structural differentiation of human uterine luminal and glandular epithelium during early pregnancy: an ultrastructural and immunohistochemical study.

    PubMed

    Demir, R; Kayisli, U A; Celik-Ozenci, C; Korgun, E T; Demir-Weusten, A Y; Arici, A

    2002-01-01

    The differentiation of human endometrial epithelium is a dynamic event that occurs throughout the menstrual cycle and early pregnancy. The structural transformation and differentiation of human uterine luminal and glandular epithelium of early human pregnancy (n=14) was investigated ultrastructurally and immunohistochemically using antibodies against cytokeratin (CT), endothelial marker CD31, Fas, and proliferating cell nuclear antigen (PCNA). Ultrastructurally, luminal epithelial cells showed distinctive euchromatic nuclei with prominent nucleoli and relatively loose cell membranes in all poles (apical to basal). Subcellular components were easily recognized in luminal epithelium except in degenerating cells. Mainly two cell types, dark and clear cells, formed the glandular epithelium. In the early gestation period, microvilli were abundant on the apical and apico-lateral poles of these cells. Only a few cytoplasmic projections were observed in dark cells. Numerous cilia were observed on the apical pole of some clear cells, located at the adluminal segment. In contrast, dark cells lacked cilia, nuclear channels, or giant mitochondrial profiles. Glycogen synthesis and apocrine secretion were recognizable for several days during early gestation. The apocrine secretory activity differed among dark cells of the glandular epithelium. The immunoreactivity of PCNA and Fas, and ultrastructural observations in the glandular epithelium suggest that, even in different segments of the same gland, epithelial cells do not regress during early gestation, but proliferate, perhaps representing a resistance against trophoblastic invasion. These morphological and molecular changes suggest that both luminal and glandular epithelium may play an important role in cellular defense and limitation for trophoblastic invasion during early pregnancy since plasma membrane alterations of the surface epithelium take place at the apical, basal and lateral poles compared to early secretory phase

  13. The ultrastructure of conjunctival melanocytic tumors.

    PubMed Central

    Jakobiec, F A

    1984-01-01

    The ultrastructure of conjunctival melanocytic lesions in 49 patients was evaluated to find significant differences between benign and malignant cells. The patients studied included 9 with benign epithelial (racial) melanosis, 2 with pigmented squamous cell papillomas, 16 with conjunctival nevi, 18 with primary acquired melanosis, and 11 with invasive nodules of malignant melanoma. In benign epithelial melanosis, dendritic melanocytes were situated along the basement membrane region of the conjunctival epithelium, with one basilar dendritic melanocyte lodged among every five or six basilar keratinocytes. The dendritic melanocytes extended arborizing cellular processes between the basilar and among the suprabasilar keratinocytes, which manifested considerable uptake of melanin granules into their cytoplasm. The benign dendritic melanocytes possessed nuclei with clumped heterochromatin at the nuclear membrane, small, tightly wound nucleoli, and large, elongated, fully melaninized melanin granules. In two patients with benign hyperplasia of the dendritic melanocytes, occasional dendritic melanocytes were located in a suprabasilar position, but were always separated from each other by keratinocytes or their processes. In the two black patients with benign pigmented squamous papillomas, the benign dendritic melanocytes were located hapharzardly at all levels of the acanthotic epithelium and not just along the basement membrane region. Melanin uptake by the proliferating keratinocytes was minimal. In benign melanocytic nevi of the conjunctiva, nevus cells within the intraepithelial junctional nests displayed a more rounded cellular configuration; short villi and broader cellular processes suggestive of abortive dendrites were found. The nuclear chromatin pattern was clumped at the nuclear membrane, but the nucleoli were somewhat larger than those of benign dendritic melanocytes in epithelial melanosis. The melanosomes were smaller and rounder than those in dendritic

  14. Nerve Regeneration Potential of Protocatechuic Acid in RSC96 Schwann Cells by Induction of Cellular Proliferation and Migration through IGF-IR-PI3K-Akt Signaling.

    PubMed

    Ju, Da-Tong; Liao, Hung-En; Shibu, Marthandam Asokan; Ho, Tsung-Jung; Padma, Viswanadha Vijaya; Tsai, Fuu-Jen; Chung, Li-Chin; Day, Cecilia Hsuan; Lin, Chien-Chung; Huang, Chih-Yang

    2015-12-31

    Peripheral nerve injuries, caused by accidental trauma, acute compression or surgery, often result in temporary or life-long neuronal dysfunctions and inflict great economic or social burdens on the patients. Nerve cell proliferation is an essential process to restore injured nerves of adults. Schwann cells play a crucial role in endogenous repair of peripheral nerves due to their ability to proliferate, migrate and provide trophic support to axons via expression of various neurotrophic factors, such as the nerve growth factor (NGF), especially after nerve injury. Protocatechuic acid (PCA) is a dihydroxybenzoic acid, a type of phenolic acid, isolated from the kernels of Alpinia oxyphylla Miq (AOF), a traditional Chinese herbal medicine the fruits of which are widely used as a tonic, aphrodisiac, anti-salivation and anti-diarrheatic. This study investigated the molecular mechanisms by which PCA induces Schwann cell proliferation by activating IGF-IR-PI3K-Akt pathway. Treatment with PCA induces phosphorylation of the insulin-like growth factor-I (IGF-I)-mediated phosphatidylinositol 3 kinase/serine - threonine kinase (PI3K/Akt) pathway, and activates expression of cell nuclear antigen (PCNA) in a dose-dependent manner. Cell cycle analysis after 18 h of treatment showed that proliferation of the RSC96 cells was enhanced by PCA treatment. The PCA induced proliferation was accompanied by modulation in the expressions of cell cycle proteins cyclin D1, cyclin E and cyclin A. Knockdown of PI3K using small interfering RNA (siRNA) and inhibition of IGF-IR receptor resulted in the reduction in cell survival proteins. The results collectively showed that PCA treatment promoted cell proliferation and cell survival via IGF-I signaling.

  15. Exposure of primary rat hepatocytes in long-term DMSO culture to selected transition metals induces hepatocyte proliferation and formation of duct-like structures.

    PubMed

    Cable, E E; Isom, H C

    1997-12-01

    We previously showed that primary rat hepatocytes plated on a rat-tail collagen coated dish and fed a chemically-defined medium supplemented with 2% dimethylsulfoxide (DMSO) can be maintained in a well-differentiated, non-replicating state for periods of several months. In this study, we show that the addition of copper, iron, and zinc to the DMSO-containing chemically defined medium induced DNA synthesis and cell replication during the first two months in culture without loss of hepatic differentiation. DNA synthesis occurred throughout the hepatocyte population without regard to cellular size. No changes were observed in properties indicative of well-differentiated hepatocytes, including cellular morphology, ultrastructure, albumin, or cytokeratin-8 expression. During the third month in culture, after the hepatocytes had become confluent, pseudoduct structures became apparent. Examination of cells lining the ducts by immunohistochemistry showed that these cells lost the ability to express albumin and stained more intensely for cytokeratin 19 and laminin. The ultrastructure of the cells lining the ducts was altered and became more characteristic of bile duct cells. Immunoelectron microscopy revealed that connexin 43, a marker of bile-duct proliferation, was expressed in the duct-like cells. We conclude that under these specific nutritive conditions, primary rat hepatocytes proliferate and, with time, begin to form duct-like structures with altered gene expression and ultrastructural properties.

  16. Short-term administration of rhGH increases markers of cellular proliferation, but not milk protein gene expression in normal lactating women.

    USDA-ARS?s Scientific Manuscript database

    Growth hormone is one of few pharmacologic agents known to augment milk production in humans. We hypothesized that recombinant human GH (rhGH) increases the expression of cell proliferation and milk protein synthesis genes. Sequential milk and blood samples collected over four days were obtained fro...

  17. Ectopic Expression of a Maize Hybrid Down-Regulated Gene ZmARF25 Decreases Organ Size by Affecting Cellular Proliferation in Arabidopsis

    PubMed Central

    Meng, Lingxue; Xing, Jiewen; Wang, Tianya; Yang, Hua; Yao, Yingyin; Peng, Huiru; Hu, Zhaorong; Sun, Qixin; Ni, Zhongfu

    2014-01-01

    Heterosis is associated with differential gene expression between hybrids and their parental lines, and the genes involved in cell proliferation played important roles. AtARF2 is a general cell proliferation repressor in Arabidopsis. In our previous study, two homologues (ZmARF10 and ZmARF25) of AtARF2 were identified in maize, but their relationship with heterosis was not elucidated. Here, the expression patterns of ZmARF10 and ZmARF25 in seedling leaves of maize hybrids and their parental lines were analyzed. The results of qRT-PCR exhibited that ZmARF25 was down-regulated in leaf basal region of hybrids. Moreover, overexpression of ZmARF25 led to reduced organ size in Arabidopsis, which was mainly due to the decrease in cell number, not cell size. In addition, the cell proliferation related genes AtANT, AtGIF1 and AtGRF5 were down-regulated in 35S::ZmARF25 transgenic lines. Collectively, we proposed that the down-regulation of ZmARF25 in maize hybrid may accelerate cell proliferation and promote leaf development, which, in turn, contributes to the observed leaf size heterosis in maize. PMID:24756087

  18. 3D Morphology, Ultrastructure and Development of Ceratomyxa puntazzi Stages: First Insights into the Mechanisms of Motility and Budding in the Myxozoa

    PubMed Central

    Alama-Bermejo, Gema; Bron, James Emmanuel; Raga, Juan Antonio; Holzer, Astrid Sibylle

    2012-01-01

    Free, amoeboid movement of organisms within media as well as substrate-dependent cellular crawling processes of cells and organisms require an actin cytoskeleton. This system is also involved in the cytokinetic processes of all eukaryotic cells. Myxozoan parasites are known for the disease they cause in economical important fishes. Usually, their pathology is related to rapid proliferation in the host. However, the sequences of their development are still poorly understood, especially with regard to pre-sporogonic proliferation mechanisms. The present work employs light microscopy (LM), electron microscopy (SEM, TEM) and confocal laser scanning microscopy (CLSM) in combination with specific stains (Nile Red, DAPI, Phalloidin), to study the three-dimensional morphology, motility, ultrastructure and cellular composition of Ceratomyxa puntazzi, a myxozoan inhabiting the bile of the sharpsnout seabream. Our results demonstrate the occurrence of two C. puntazzi developmental cycles in the bile, i.e. pre-sporogonic proliferation including frequent budding as well as sporogony, resulting in the formation of durable spore stages and we provide unique details on the ultrastructure and the developmental sequence of bile inhabiting myxozoans. The present study describes, for the first time, the cellular components and mechanisms involved in the motility of myxozoan proliferative stages, and reveals how the same elements are implicated in the processes of budding and cytokinesis in the Myxozoa. We demonstrate that F-actin rich cytoskeletal elements polarize at one end of the parasites and in the filopodia which are rapidly de novo created and re-absorbed, thus facilitating unidirectional parasite motility in the bile. We furthermore discover the myxozoan mechanism of budding as an active, polarization process of cytokinesis, which is independent from a contractile ring and thus differs from the mechanism, generally observed in eurkaryotic cells. We hereby demonstrate that CLSM

  19. Tendon’s ultrastructure

    PubMed Central

    Tresoldi, Ilaria; Oliva, Francesco; Benvenuto, Monica; Fantini, Massimo; Masuelli, Laura; Bei, Roberto; Modesti, Andrea

    2013-01-01

    Summary The structure of a tendon is an important example of complexity of ECM three-dimensional organization. The extracellular matrix (ECM) is a macromolecular network with both structural and regulatory functions. ECM components belong to four major types of macromolecules: the collagens, elastin, proteoglycans, and noncollagenous glycoproteins. Tendons are made by a fibrous, compact connective tissue that connect muscle to bone designed to transmit forces and withstand tension during muscle contraction. Here we show the ultrastructural features of tendon’s components. PMID:23885339

  20. Gremlin induces cell proliferation and extra cellular matrix accumulation in mouse mesangial cells exposed to high glucose via the ERK1/2 pathway

    PubMed Central

    2013-01-01

    Background Gremlin, a bone morphogenetic protein antagonist, plays an important role in the pathogenesis of diabetic nephropathy (DN). However, the specific molecular mechanism underlying Gremlin’s involvement in DN has not been fully elucidated. In the present study, we investigated the role of Gremlin on cell proliferation and accumulation of extracellular matrix (ECM) in mouse mesangial cells (MMCs), and explored the relationship between Gremlin and the ERK1/2 pathway. Methods To determine expression of Gremlin in MMCs after high glucose (HG) exposure, Gremlin mRNA and protein expression were evaluated using real-time polymerase chain reaction and western blot analysis, respectively. To determine the role of Gremlin on cell proliferation and accumulation of ECM, western blot analysis was used to assess expression of pERK1/2, transforming growth factor-β1 (TGF-β1) and connective tissue growth factor (CTGF). Cell proliferation was examined by bromodeoxyuridine (BrdU) ELISA, and accumulation of collagen IV was measured using a radioimmunoassay. This enabled the relationship between Gremlin and ERK1/2 pathway activation to be investigated. Results HG exposure induced expression of Gremlin, which peaked 12 h after HG exposure. HG exposure alone or transfection of normal-glucose (NG) exposed MMCs with Gremlin plasmid (NG + P) increased cell proliferation. Transfection with Gremlin plasmid into MMCs previously exposed to HG (HG + P) significantly increased this HG-induced phenomenon. HG and NG + P conditions up-regulated protein levels of TGF-β1, CTGF and collagen IV accumulation, while HG + P significantly increased levels of these further. Inhibition of Gremlin with Gremlin siRNA plasmid reversed the HG-induced phenomena. These data indicate that Gremlin can induce cell proliferation and accumulation of ECM in MMCs. HG also induced the activation of the ERK1/2 pathway, which peaked 24 h after HG exposure. HG and NG + P conditions induced

  1. Ultrastructural hepatocytic alterations induced by silver nanoparticle toxicity.

    PubMed

    Almansour, Mansour; Sajti, Laszlo; Melhim, Walid; Jarrar, Bashir M

    2016-01-01

    Silver nanoparticles (SNPs) are widely used in nanomedicine and consuming products with potential risk to human health. While considerable work was carried out on the molecular, biochemical, and physiological alterations induced by these particles, little is known of the ultrastructural pathological alterations that might be induced by nanosilver materials. The aim of the present work is to investigate the hepatocyte ultrastructural alterations that might be induced by SNP exposure. Male rats were subjected to a daily single dose (2 mg/kg) of SNPs (15-35 nm diameter) for 21 days. Liver biopsies from all rats under study were processed for transmission electron microscopy examination. The following hepatic ultrastructural alterations were demonstrated: mitochondria swelling and crystolysis, endoplasmic reticulum disruption, cytoplasmic vacuolization, lipid droplets accumulation, glycogen depletion, karyopyknosis, apoptosis, sinusoidal dilatation, Kupffer cells activation, and myelin figures formation. The current findings may indicate that SNPs can induce hepatocyte organelles alteration, leading to cellular damage that may affect the function of the liver. These findings might indicate that SNPs potentially trigger heptocyte ultrastructural alterations that may affect the function of the liver with potential risk on human health in relation to numerous applications of these particles. More work is needed to elucidate probable ultrastructural alterations in the vital organs that might result from nanosilver toxicity.

  2. Ultrastructural Characteristics of Rat Hepatic Oval Cells and Their Intercellular Contacts in the Model of Biliary Fibrosis: New Insights into Experimental Liver Fibrogenesis.

    PubMed

    Lotowska, Joanna Maria; Sobaniec-Lotowska, Maria Elzbieta; Lebensztejn, Dariusz Marek; Daniluk, Urszula; Sobaniec, Piotr; Sendrowski, Krzysztof; Daniluk, Jaroslaw; Reszec, Joanna; Debek, Wojciech

    2017-01-01

    Recently, it has been emphasized that hepatic progenitor/oval cells (HPCs) are significantly involved in liver fibrogenesis. We evaluated the multipotential population of HPCs by transmission electron microscope (TEM), including relations with adherent hepatic nonparenchymal cells (NPCs) in rats with biliary fibrosis induced by bile duct ligation (BDL). The study used 6-week-old Wistar Crl: WI(Han) rats after BDL for 1, 6, and 8 weeks. Current ultrastructural analysis showed considerable proliferation of HPCs in experimental intensive biliary fibrosis. HPCs formed proliferating bile ductules and were scattered in periportal connective tissue. We distinguished 4 main types of HPCs: 0, I, II (bile duct-like cells; most common), and III (hepatocyte-like cells). We observed, very seldom presented in literature, cellular interactions between HPCs and adjacent NPCs, especially commonly found transitional hepatic stellate cells (T-HSCs) and Kupffer cells/macrophages. We showed the phenomenon of penetration of the basement membrane of proliferating bile ductules by cytoplasmic processes sent by T-HSCs and the formation of direct cell-cell contact with ductular epithelial cells related to HPCs. HPC proliferation induced by BDL evidently promotes portal fibrogenesis. Better understanding of the complex cellular interactions between HPCs and adjacent NPCs, especially T-HSCs, may help develop antifibrotic therapies in the future.

  3. Ultrastructural Characteristics of Rat Hepatic Oval Cells and Their Intercellular Contacts in the Model of Biliary Fibrosis: New Insights into Experimental Liver Fibrogenesis

    PubMed Central

    Lebensztejn, Dariusz Marek; Daniluk, Urszula; Sobaniec, Piotr; Sendrowski, Krzysztof; Daniluk, Jaroslaw; Debek, Wojciech

    2017-01-01

    Purpose Recently, it has been emphasized that hepatic progenitor/oval cells (HPCs) are significantly involved in liver fibrogenesis. We evaluated the multipotential population of HPCs by transmission electron microscope (TEM), including relations with adherent hepatic nonparenchymal cells (NPCs) in rats with biliary fibrosis induced by bile duct ligation (BDL). Methods The study used 6-week-old Wistar Crl: WI(Han) rats after BDL for 1, 6, and 8 weeks. Results Current ultrastructural analysis showed considerable proliferation of HPCs in experimental intensive biliary fibrosis. HPCs formed proliferating bile ductules and were scattered in periportal connective tissue. We distinguished 4 main types of HPCs: 0, I, II (bile duct-like cells; most common), and III (hepatocyte-like cells). We observed, very seldom presented in literature, cellular interactions between HPCs and adjacent NPCs, especially commonly found transitional hepatic stellate cells (T-HSCs) and Kupffer cells/macrophages. We showed the phenomenon of penetration of the basement membrane of proliferating bile ductules by cytoplasmic processes sent by T-HSCs and the formation of direct cell-cell contact with ductular epithelial cells related to HPCs. Conclusions HPC proliferation induced by BDL evidently promotes portal fibrogenesis. Better understanding of the complex cellular interactions between HPCs and adjacent NPCs, especially T-HSCs, may help develop antifibrotic therapies in the future. PMID:28769978

  4. Depletion of tumour glutathione in vivo by buthionine sulphoximine: modulation by the rate of cellular proliferation and inhibition of cancer growth.

    PubMed Central

    Terradez, P; Asensi, M; Lasso de la Vega, M C; Puertes, I R; Viña, J; Estrela, J M

    1993-01-01

    We have investigated in Ehrlich-ascites-tumour-bearing mice the effect of buthionine sulphoximine (BSO), a selective inhibitor of GSH synthesis, on the rate of GSH depletion of tumour versus normal tissues and its relation to tumour cell proliferation. In normal tissues, GSH and GSSG remain unchanged or close to normal values during tumour growth, even at the last stage of growth when the animal is close to death. After administration of a single dose of BSO (4 mmol/kg), the rates of GSH depletion and recovery in the tumour and in several normal tissues are very different. BSO depletes GSH in cancer cells to a level of 0.3-0.4 mumol/g. The fall in GSH levels is faster when tumour cells do not proliferate actively. Four treatments of 4 mmol of BSO/kg at 48 h intervals induce a significant decrease (about 44%) in tumour growth. Our data show that the rate of BSO-induced GSH depletion in cancer cells depends on the stage of tumour growth, and that BSO administration also inhibits cancer-cell proliferation. A mechanism involving changes in protein kinase C activity and intracellular pH is proposed to explain the inhibition of cancer growth elicited by BSO. PMID:8503882

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

    SciTech Connect

    Zhao Lanjuan; Wang Lu; Ren Hao; Cao Jie; Li Li; Ke Jinshan; Qi Zhongtian . E-mail: qizt53@hotmail.com

    2005-04-15

    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. Cell membrane CD44v6 levels in squamous cell carcinoma of the lung: association with high cellular proliferation and high concentrations of EGFR and CD44v5.

    PubMed

    Ruibal, Álvaro; Aguiar, Pablo; Del Río, María Carmen; Nuñez, Matilde Isabel; Pubul, Virginia; Herranz, Michel

    2015-02-18

    Membranous CD44v6 levels in tumors and surrounding samples obtained from 94 patients with squamous cell lung carcinomas were studied and compared to clinical stage, cellular proliferation, membranous CD44v5 levels, epidermal growth factor receptor EGFR and cytoplasmatic concentrations of CYFRA 21.1. CD44v6 positive values were observed in 33/38 non-tumor samples and in 76/94 tumor samples, but there were not statistically significant differences between both subgroups. In CD44v6 positive tumor samples, CD44v6 was not associated with clinical stage, histological grade, ploidy and lymph node involvement, but significant association was found with high cellular proliferation. Likewise, CD44v6 positive tumors had significantly higher levels of EGFR and CD44v5. In patients with squamous cell lung carcinomas and clinical stage I, positive CD44v6 cases were associated with the same parameters. Furthermore, positive CD44v5 squamous tumors were associated significantly with histological grade III and lower levels of CYFRA21.1. Our findings support the value of CD44v6 as a possible indicator of poor outcome in patients with squamous lung carcinomas.

  7. Ultrastructural alterations in allylamine cardiovascular toxicity. Late myocardial and vascular lesions.

    PubMed Central

    Boor, P. J.; Ferrans, V. J.

    1985-01-01

    The late myocardial and vascular ultrastructural changes in rat hearts following consumption of the cardiovascular toxin allylamine were studied. Rats were given 0.1% allylamine HCl in drinking water for 10-104 days. From 10 to 21 days, there was organization of acute myocardial necrosis by macrophages and scattered polymorphonuclear leukocytes with prominent interstitial-cell proliferation. Alterations at 21-104 days included extensive scarring with formation of dense mature collagen with scattered fibroblasts present, grossly evident left-ventricular aneurysm, and gross and microscopic changes similar to those observed in the secondary form of endocardial fibroelastosis. Areas of scar contained highly cellular foci of smooth-muscle cells, myofibroblasts, and abundant extracellular elastin. Cardiac myocytes frequently showed markedly disorganized myofilaments, bizarrely distorted mitochondria with condensed cristae, and other severe degenerative changes. Small vessels within and adjacent to scar showed proliferation of intimal smooth-muscle cells. Endothelial lesions or recent or organized thrombi were not seen. Focal endocardial metaplasia, consisting of both chondroid and osseous tissue, was found in areas of transmural scarring, or ventricular aneurysm. Chondrocytes had the overall nuclear and cellular morphology, abundant rough endoplasmic reticulum, and surrounding lacunae typical of mature fibrocartilage. In some areas, the collagen matrix was undergoing calcification with the typical cross-banded pattern of calcifying connective tissue. Osteocytes were located in a densely calcified bone matrix and displayed characteristic cellular extensions into surrounding canaliculi. These findings indicate a severe myocardial, small-vessel, and endocardial injury during the course of chronic allylamine intoxication. Images Figure 13 Figure 14 Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 15 Figure

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

    SciTech Connect

    Jiang, Chen-Yi; Gao, Yuan; Wang, Xing-Jie; Ruan, Yuan; Bei, Xiao-Yu; Wang, Xiao-Hai; Jing, Yi-Feng; Zhao, Wei; Jiang, Qi; Li, Jia; Han, Bang-Min; Xia, Shu-Jie; Zhao, Fu-Jun

    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. Ultrastructural evidence for differentiation in a human glioblastoma cell line treated with inhibitors of eicosanoid metabolism

    SciTech Connect

    Wilson, D.E.; Anderson, K.M. ); Seed, T.M. )

    1990-01-01

    Human glioblastoma cells incubated in the presence of inhibitors of eicosanoid biosynthesis show decreased cellular proliferation without cytotoxicity. The authors studied the ultrastructural morphology of a human glioblastoma cell line cultured with nordihydroguaiaretic acid (NDGA), a lipoxygenase inhibitor, or 5,8,11,14-eicosatetraynoic acid, a cyclooxygenase and lipoxygenase inhibitor. When glioblastoma cells were treated for 3 days with antiproliferative concentrations of either agent, they shared many morphological characteristics, including evidence for increased astrocytic differentiation with only limited signs of toxicity. The inhibited glioma cells demonstrated an increase in the number and length of astrocytic processes containing greater numbers of glial filaments, and the NDGA-treated cells also demonstrated extensive lateral pseudopod formation along the processes. The glioblastoma cell shape also become more elongated, losing the usual nuclear lobularity and nuclear inclusions, especially in NDGA-treated cells. Many cytoplasmic organelles packed the cytosol of the inhibited glioma cells, including prominent Golgi apparatus, dilated smooth endoplasmic reticulum evolving into dilated vesicles, cytoplasmic vacuoles, and numerous concentric laminations. There was limited evidence for toxicity, however, as the mitochondria were more pleomorphic with some mitochondrial distension and disruption of the cristae along with an increase in cytoplasmic vacuolization. The authors conclude that the inhibitors of eicosanoid biosynthesis. NDGA and 5,8,11,14-eicosatetraynoic acid, not only suppress glioblastoma cell proliferation, but also include increased astrocytic differentiation.

  10. Laser photobiomodulation of proliferation of cells in culture: a review of human and animal studies.

    PubMed

    Peplow, Philip V; Chung, Tzu-Yun; Baxter, G David

    2010-08-01

    The aim of this article was to review experimental studies of laser irradiation of human and animal cells in culture to assess the photobiomodulatory effects of such irradiation. Previous studies have shown that various types of cells respond differently to laser irradiation, depending on irradiation parameters. Cellular outcomes measured or examined include cell numbers, cell viability, and ultrastructural features. A review of these studies may provide a further insight into the clinical effects brought about by laser light on cells and tissues, including laser effects in wound healing and repair of nerves and skeletal muscle after injury. A systematic review was completed of original research articles investigating the effects of laser therapy on human and animal cells in culture (January 2002 to September 2009). Relevant articles were primarily sourced from PubMed and Medline by using EndNote X1, and from secondary searches. Search terms were "cell proliferation," "laser therapy," "laser irradiation," "laser phototherapy," and "phototherapy." In total, 46 relevant articles were included in the review, comprising work completed on a variety of cell types. Although results consistently demonstrated the potential of laser irradiation to affect cellular proliferation in a wavelength- and dosage-dependent manner, the relevance of other key irradiation parameters, such as irradiance, to such effects remained unclear. Findings from studies of cells in culture clearly demonstrate the ability of laser irradiation to modulate (typically stimulate) cellular proliferation. The relevance of some irradiation parameters remains occult and represents an important area for further research.

  11. NaBC1 is a ubiquitous electrogenic Na+ -coupled borate transporter essential for cellular boron homeostasis and cell growth and proliferation.

    PubMed

    Park, Meeyoung; Li, Qin; Shcheynikov, Nikolay; Zeng, Weizong; Muallem, Shmuel

    2004-11-05

    Boron is a vital micronutrient in plants and may be essential for animal growth and development. Whereas the role of boron in the life cycle of plants is well documented, nothing is known about boron homeostasis and function in animal cells. NaBC1, the mammalian homolog of AtBor1, is a borate transporter. In the absence of borate, NaBC1 conducts Na(+) and OH(-) (H(+)), while in the presence of borate, NaBC1 functions as an electrogenic, voltage-regulated, Na(+)-coupled B(OH)(4)(-) transporter. At low concentrations, borate activated the MAPK pathway to stimulate cell growth and proliferation, and at high concentrations, it was toxic. Accordingly, overexpression of NaBC1 shifted both effects of borate to the left, whereas knockdown of NaBC1 halted cell growth and proliferation. These findings may reveal a previously unrecognized role for NaBC1 in borate homeostasis and open the way to better understanding of the many presumed physiological roles of borate in animals.

  12. Potent and Selective KDM5 Inhibitor Stops Cellular Demethylation of H3K4me3 at Transcription Start Sites and Proliferation of MM1S Myeloma Cells.

    PubMed

    Tumber, Anthony; Nuzzi, Andrea; Hookway, Edward S; Hatch, Stephanie B; Velupillai, Srikannathasan; Johansson, Catrine; Kawamura, Akane; Savitsky, Pavel; Yapp, Clarence; Szykowska, Aleksandra; Wu, Na; Bountra, Chas; Strain-Damerell, Claire; Burgess-Brown, Nicola A; Ruda, Gian Filippo; Fedorov, Oleg; Munro, Shonagh; England, Katherine S; Nowak, Radoslaw P; Schofield, Christopher J; La Thangue, Nicholas B; Pawlyn, Charlotte; Davies, Faith; Morgan, Gareth; Athanasou, Nick; Müller, Susanne; Oppermann, Udo; Brennan, Paul E

    2017-03-16

    Methylation of lysine residues on histone tail is a dynamic epigenetic modification that plays a key role in chromatin structure and gene regulation. Members of the KDM5 (also known as JARID1) sub-family are 2-oxoglutarate (2-OG) and Fe(2+)-dependent oxygenases acting as histone 3 lysine 4 trimethyl (H3K4me3) demethylases, regulating proliferation, stem cell self-renewal, and differentiation. Here we present the characterization of KDOAM-25, an inhibitor of KDM5 enzymes. KDOAM-25 shows biochemical half maximal inhibitory concentration values of <100 nM for KDM5A-D in vitro, high selectivity toward other 2-OG oxygenases sub-families, and no off-target activity on a panel of 55 receptors and enzymes. In human cell assay systems, KDOAM-25 has a half maximal effective concentration of ∼50 μM and good selectivity toward other demethylases. KDM5B is overexpressed in multiple myeloma and negatively correlated with the overall survival. Multiple myeloma MM1S cells treated with KDOAM-25 show increased global H3K4 methylation at transcriptional start sites and impaired proliferation. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Loss of the Histone Pre-mRNA Processing Factor Stem-Loop Binding Protein in Drosophila Causes Genomic Instability and Impaired Cellular Proliferation

    PubMed Central

    Salzler, Harmony R.; Davidson, Jean M.; Montgomery, Nathan D.; Duronio, Robert J.

    2009-01-01

    Background Metazoan replication-dependent histone mRNAs terminate in a conserved stem-loop structure rather than a polyA tail. Formation of this unique mRNA 3′ end requires Stem-loop Binding Protein (SLBP), which directly binds histone pre-mRNA and stimulates 3′ end processing. The 3′ end stem-loop is necessary for all aspects of histone mRNA metabolism, including replication coupling, but its importance to organism fitness and genome maintenance in vivo have not been characterized. Methodology/Principal Findings In Drosophila, disruption of the Slbp gene prevents normal histone pre-mRNA processing and causes histone pre-mRNAs to utilize the canonical 3′ end processing pathway, resulting in polyadenylated histone mRNAs that are no longer properly regulated. Here we show that Slbp mutants display genomic instability, including loss of heterozygosity (LOH), increased presence of chromosome breaks, tetraploidy, and changes in position effect variegation (PEV). During imaginal disc growth, Slbp mutant cells show defects in S phase and proliferate more slowly than control cells. Conclusions/Significance These data are consistent with a model in which changing the 3′ end of histone mRNA disrupts normal replication-coupled histone mRNA biosynthesis and alters chromatin assembly, resulting in genomic instability, inhibition of cell proliferation, and impaired development. PMID:19997601

  14. Exposure to global system for mobile communication (GSM) cellular phone radiofrequency alters gene expression, proliferation, and morphology of human skin fibroblasts.

    PubMed

    Pacini, Stefania; Ruggiero, Marco; Sardi, Iacopo; Aterini, Stefano; Gulisano, Franca; Gulisano, Massimo

    2002-01-01

    Human skin fibroblasts were exposed to global system for mobile communication (GSM) cellular phone radiofrequency for 1 h. GSM exposure induced alterations in cell morphology and increased the expression of mitogenic signal transduction genes (e.g., MAP kinase kinase 3, G2/mitotic-specific cyclin G1), cell growth inhibitors (e.g., transforming growth factor-beta), and genes controlling apoptosis (e.g., bax). A significant increase in DNA synthesis and intracellular mitogenic second messenger formation matched the high expression of MAP kinase family genes. These findings show that these electromagnetic fields have significant biological effects on human skin fibroblasts.

  15. Binding of sFRP-3 to EGF in the Extra-Cellular Space Affects Proliferation, Differentiation and Morphogenetic Events Regulated by the Two Molecules

    PubMed Central

    Tosoni, Daniela; Borello, Ugo; Sampaolesi, Maurilio; Sciorati, Clara; Cannata, Stefano; Clementi, Emilio; Brunelli, Silvia; Cossu, Giulio

    2008-01-01

    Background sFRP-3 is a soluble antagonist of Wnts, widely expressed in developing embryos. The Wnt gene family comprises cysteine-rich secreted ligands that regulate cell proliferation, differentiation, organogenesis and oncogenesis of different organisms ranging from worms to mammals. In the canonical signal transduction pathway Wnt proteins bind to the extracellular domain of Frizzled receptors and consequently recruit Dishevelled (Dsh) to the cell membrane. In addition to Wnt membrane receptors belonging to the Frizzled family, several other molecules have been described which share homology in the CRD domain and lack the putative trans-membrane domain, such as sFRP molecules (soluble Frizzled Related Protein). Among them, sFRP-3 was originally isolated from bovine articular cartilage and also as a component of the Spemann organizer. sFRP-3 blocks Wnt-8 induced axis duplication in Xenopus embryos and binds to the surface of cells expressing a membrane-anchored form of Wnt-1. Injection of sFRP-3 mRNA blocks expression of XMyoD mRNA and leads to embryos with enlarged heads and shortened trunks. Methodology/Principal Findings Here we report that sFRP-3 specifically blocks EGF-induced fibroblast proliferation and foci formation. Over-expression of sFRP-3 reverts EGF-mediated inhibition of hair follicle development in the mouse ectoderm while its ablation in Xenopus maintains EGF-mediated inhibition of ectoderm differentiation. Conversely, over-expression of EGF reverts the inhibition of somitic myogenesis and axis truncation in Xenopus and mouse embryos caused by sFRP-3. In vitro experiments demonstrated a direct binding of EGF to sFRP-3 both on heparin and on the surface of CHO cells where the molecule had been membrane anchored. Conclusions/Significance sFRP-3 and EGF reciprocally inhibit their effects on cell proliferation, differentiation and morphogenesis and indeed are expressed in contiguous domains of the embryo, suggesting that in addition to their

  16. Altered RECQL5 expression in urothelial bladder carcinoma increases cellular proliferation and makes RECQL5 helicase activity a novel target for chemotherapy

    PubMed Central

    Patterson, Karl; Arya, Lovleen; Bottomley, Sarah; Morgan, Susan; Cox, Angela; Catto, James; Bryant, Helen E.

    2016-01-01

    RECQ helicases are a family of enzymes with both over lapping and unique functions. Functional autosomal recessive loss of three members of the family BLM, WRN and RECQL4, results in hereditary human syndromes characterized by cancer predisposition and premature aging, but despite the finding that RECQL5 deficient mice are cancer prone, no such link has been made to human RECQL5. Here we demonstrate that human urothelial carcinoma of the bladder (UCC) has increased expression of RECQL5 compared to normal bladder tissue and that increasing RECQL5 expression can drive proliferation of normal bladder cells and is associated with poor prognosis. Further, by expressing a helicase dead RECQL5 and by depleting bladder cancer cells of RECQL5 we show that inhibition of RECQL5 activity has potential as a new target for treatment of UCC. PMID:27764811

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

    PubMed

    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.

  18. Cytoskeletal protein Flightless (Flii) is elevated in chronic and acute human wounds and wound fluid: neutralizing its activity in chronic but not acute wound fluid improves cellular proliferation.

    PubMed

    Ruzehaji, Nadira; Grose, Randall; Krumbiegel, Doreen; Zola, Heddy; Dasari, Pallave; Wallace, Hilary; Stacey, Michael; Fitridge, Robert; Cowin, Allison J

    2012-01-01

    Chronic non-healing wounds form a medical need which will expand as the population ages and the obesity epidemic grows. Whilst the complex mechanisms underlying wound repair are not fully understood, remodelling of the actin cytoskeleton plays a critical role. Elevated expression of the actin cytoskeletal protein Flightless I (Flii) is known to impair wound outcomes. To determine if Flii is involved in the impaired healing observed in chronic wounds, its expression in non-healing human wounds from patients with venous leg ulcers was determined and compared to its expression in acute wounds and unwounded skin. Increased expression of Flii was observed in both chronic and acute wounds with wound fluid and plasma also containing secreted Flii protein. Inflammation is a key aspect of wound repair and fluorescence-activated cell sorting (FACS) analysis revealed Flii was located in neutrophils within the blood and that it co-localised with CD16+ neutrophils in chronic wounds. The function of secreted Flii was investigated as both chronic wound fluid and Flii have previously been shown to inhibit fibroblast proliferation. To determine if the inhibitory effect of wound fluid was due in part to the presence of Flii, wound fluids were depleted of Flii using Flii-specific neutralizing antibodies (FnAb). Flii depleted chronic wound fluid no longer inhibited fibroblast proliferation, suggesting that Flii may contribute to the inhibitory effect of chronic wound fluid on fibroblast function. Application of FnAbs to chronic wounds may therefore be a novel approach used to improve the local environment of non-healing wounds and potentially improve healing outcomes.

  19. Diagnostic and prognostic value of cellular proliferation assessment with Ki-67 protein in dogs suffering from benign and malignant perianal tumors.

    PubMed

    Brodzki, Adam; Łopuszyński, Wojciech; Brodzki, Piotr; Tatara, Marcin R

    2014-01-01

    In the perianal region of carnivores, skin consists of modified sebaceous glands called perianal glands. Tumors originating from perianal glands are the third most frequent type of neoplasm in male dogs after neoplastic diseases of testes and skin. Ki-67 is a nuclear non-histone protein considered a proliferation marker in normal and neoplastic proliferating cells. Previous investigations revealed that Ki-67 expression may be used as a prognostic factor for breast cancer in humans. Thus, the aim of this study was to estimate the diagnostic and prognostic value of Ki-67 evaluation in dogs suffering from benign and malignant perianal tumors. The highest value of the Ki-67 index was obtained in the carcinoma group (18.50% ± 2.68), significantly higher compared to the values obtained in the control tissue (7.63% ± 2.12) and adenoma (7.33% ± 1.06; all P < 0.05). Statistically significant differences in the Ki-67 index were not found between the epithelioma group (11.95% ± 1.96) and all other groups (P < 0.05). This investigation on dogs with perianal gland tumors has shown significantly increased expression of Ki-67 antigen in carcinoma cells, while the expression of this protein was similar in the case of control tissues, adenoma and epithelioma. Thus, it may be postulated that Ki-67 evaluation in perianal gland tumors in dogs may serve as a useful marker possessing high diagnostic and prognostic value and enabling differentiation of malignant and benign tumors.

  20. Basic Fibroblast Growth Factor Inhibits Apoptosis and Promotes Proliferation of Adipose-Derived Mesenchymal Stromal Cells Isolated from Patients with Type 2 Diabetes by Reducing Cellular Oxidative Stress

    PubMed Central

    2017-01-01

    Type 2 diabetes (T2D) is a chronic metabolic disorder affecting increasing number of people in developed countries. Therefore new strategies for treatment of T2D and its complications are of special interest. Nowadays, cellular therapies involving mesenchymal stromal cells that reside in adipose tissue (ASCs) constitute a promising approach; however, there are still many obstacles concerning safety and effectiveness that need to be overcome before ASCs could be engaged for the treatment of diabetes mellitus. One of the challenges is preventing ASCs from deterioration caused by elevated oxidative stress present in diabetes milieu. In the current study we investigated the effect of basic fibroblast growth factor (bFGF) treatment on ASCs isolated from patients with diagnosed T2D. We demonstrate here that cell exposition to bFGF in 5 and 10 ng/mL dosages results in improved morphology, increased proliferative activity, reduced cellular senescence and apoptosis, and decreased oxidative stress, indicating recovery of ASCs' function impaired by T2D. Therefore our results provide a support for bFGF as a potential therapeutic agent for improving stem cell-based approaches for the treatment of diabetes mellitus and its complications. PMID:28168007

  1. Post-embryonic development of the Malpighian tubules in Apis mellifera (Hymenoptera) workers: morphology, remodeling, apoptosis, and cell proliferation.

    PubMed

    Gonçalves, Wagner Gonzaga; Fernandes, Kenner Morais; Santana, Weyder Cristiano; Martins, Gustavo Ferreira; Zanuncio, José Cola; Serrão, José Eduardo

    2017-10-07

    The honeybee Apis mellifera has ecological and economic importance; however, it experiences a population decline, perhaps due to exposure to toxic compounds, which are excreted by Malpighian tubules. During metamorphosis of A. mellifera, the Malpighian tubules degenerate and are formed de novo. The objective of this work was to verify the cellular events of the Malpighian tubule renewal in the metamorphosis, which are the gradual steps of cell remodeling, determining different cell types and their roles in the excretory activity in A. mellifera. Immunofluorescence and ultrastructural analyses showed that the cells of the larval Malpighian tubules degenerate by apoptosis and autophagy, and the new Malpighian tubules are formed by cell proliferation. The ultrastructure of the cells in the Malpighian tubules suggest that cellular remodeling only occurs from dark-brown-eyed pupae, indicating the onset of excretion activity in pupal Malpighian tubules. In adult forager workers, two cell types occur in the Malpighian tubules, one with ultrastructural features (abundance of mitochondria, vacuoles, microvilli, and narrow basal labyrinth) for primary urine production and another cell type with dilated basal labyrinth, long microvilli, and absence of spherocrystals, which suggest a role in primary urine re-absorpotion. This study suggests that during the metamorphosis, Malpighian tubules are non-functional until the light-brown-eyed pupae, indicating that A. mellifera may be more vulnerable to toxic compounds at early pupal stages. In addition, cell ultrastructure suggests that the Malpighian tubules may be functional from dark-brown-eyed pupae and acquire greater complexity in the forager worker bee.

  2. Poly (C)-binding protein 2 (PCBP2) promotes the progression of esophageal squamous cell carcinoma (ESCC) through regulating cellular proliferation and apoptosis.

    PubMed

    Ye, Jinjun; Zhou, Guoren; Zhang, Zhi; Sun, Lei; He, Xia; Zhou, Jianwei

    2016-08-01

    PCBP2 (Poly(C)-binding protein 2) is a member of PCBP family, which has many functions including mRNA stabilization, translational silence and translational enhancement performed by their poly(C)-binding ability. The abnormal expression of PCBP2 was correlated with various carcinomas. However, the significance and mechanism of PCBP2 in esophageal squamous cell carcinoma (ESCC) progression remain unclear. In this study, Western Blot and immunohistochemistry (IHC) analysis revealed that PCBP2 was overexpressed in ESCC tissues and cell lines. Statistical results also indicated that PCBP2 expression level was significantly positively correlated with ESCC clinicopathological parameters such as tumor grade and tumor size. Furthermore, PCBP2 expression level could also be recognized as an independent prognostic factor for ESCC patients' overall survival. Serum starvation and refeeding assay along with PCBP2-shRNA transfection demonstrated that PCBP2 expression promoted proliferation of ESCC cells. The results above are partly due to growth arrest of cell cycle at G1/S phase. We also found that reduced PCBP2 expression might induce ESCC cell apoptosis with increased cleaved caspase3 expression. Overall, our findings indicated that PCBP2 might be involved in the ESCC progression and be considered as a new treatment target in ESCC.

  3. Effect of Mycobacterium bovis BCG Vaccination on Mycobacterium-Specific Cellular Proliferation and Tumor Necrosis Factor Alpha Production from Distinct Guinea Pig Leukocyte Populations

    PubMed Central

    Lasco, Todd M.; Yamamoto, Toshiko; Yoshimura, Teizo; Allen, Shannon Sedberry; Cassone, Lynne; McMurray, David N.

    2003-01-01

    In this study, we focused on three leukocyte-rich guinea pig cell populations, bronchoalveolar lavage (BAL) cells, resident peritoneal cells (PC), and splenocytes (SPC). BAL cells, SPC, and PC were stimulated either with live attenuated Mycobacterium tuberculosis H37Ra or with live or heat-killed virulent M. tuberculosis H37Rv (multiplicity of infection of 1:100). Each cell population was determined to proliferate in response to heat-killed virulent H37Rv, whereas no measurable proliferative response could be detected upon stimulation with live mycobacteria. Additionally, this proliferative capacity (in SPC and PC populations) was significantly enhanced upon prior vaccination with Mycobacterium bovis BCG. Accordingly, in a parallel set of experiments we found a strong positive correlation between production of antigen-specific bioactive tumor necrosis factor alpha (TNF-α) and prior vaccination with BCG. A nonspecific stimulus, lipopolysaccharide, failed to induce this effect on BAL cells, SPC, and PC. These results showed that production of bioactive TNF-α from mycobacterium-stimulated guinea pig cell cultures positively correlates with the vaccination status of the host and with the virulence of the mycobacterial strain. PMID:14638793

  4. HTLV-I Tax regulates the cellular proliferation through the down-regulation of PIP3-phosphatase expressions via the NF-κB pathway

    PubMed Central

    Fukuda, Ryu-ich; Tsuchiya, Kiyohito; Suzuki, Koji; Itoh, Katsuhiko; Fujita, Jun; Utsunomiya, Atae; Tsuji, Takashi

    2012-01-01

    An oncogenic retrovirus, human T-cell leukemia virus type I (HTLV-I), encodes an oncoprotein, Tax, which plays critical roles in leukemogenesis of adult T-cell leukemia/lymphoma (ATLL) through the pleiotropic actions such as transcriptional regulation, cell cycle control, and transformation. We have previously reported that PTEN and SHIP- 1, PIP3 inositol phosphatases that negatively regulate the PI3-kinase signaling cascade, are disrupted in ATLL neoplasias. Overactivation of PI3-kinase signaling has an essential role in onset of ATLL. We report here that both PTEN and SHIP-1 are downregulated by Tax through the NF-κB signaling pathway. Tax expression upregulated phosphorylated Akt, a downstream serine/threonine kinase in the PI3-kinase signaling cascade. Activation of NF-κB pathway also suppressed these phosphatases. An IκBΔN mutant which inhibits the activation of NF-κB prevented PIP3 phosphatase downregulation by Tax. The underlying mechanism of NF-κB mediated suppression of PIP3 phosphatases involved sequestration of the coactivator p300 by p65. These down-regulations of PIP3 phosphatases were found to be essential for the Tax-induced cell proliferation. Thus, our results suggest that HTLV-I Tax downregulates PIP3 phosphatases through the NF-κB pathway, resulting in increased activation of the PI3-kinase signaling cascade in human T-cells and contributing to leukemogenesis. PMID:22509484

  5. Ultrastructural Analysis of Myoblast Fusion in Drosophila

    PubMed Central

    Zhang, Shiliang; Chen, Elizabeth H.

    2015-01-01

    Summary 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 indispensable tool to reveal fusion intermediates and specific membrane events at sites of fusion. In this chapter, we describe conventional chemical fixation and high-pressure freezing/freeze substitution methods for visualizing fusion intermediates during Drosophila myoblast fusion. Furthermore, we describe an immunoelectron microscopic method for localizing specific proteins relative to the fusion apparatus. PMID:18979250

  6. Over-Expression of 60s Ribosomal L23a Is Associated with Cellular Proliferation in SAG Resistant Clinical Isolates of Leishmania donovani

    PubMed Central

    Das, Sanchita; Shah, Priyanka; Baharia, Rajendra K.; Tandon, Rati; Khare, Prashant; Sundar, Shyam; Sahasrabuddhe, Amogh A.; Siddiqi, M. I.; Dube, Anuradha

    2013-01-01

    Background 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. Methodology and principal findings 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. Conclusion/Significance 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. PMID:24340105

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

    PubMed

    Das, Sanchita; Shah, Priyanka; Baharia, Rajendra K; Tandon, Rati; Khare, Prashant; Sundar, Shyam; Sahasrabuddhe, Amogh A; Siddiqi, M I; Dube, Anuradha

    2013-01-01

    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.

  8. Studies on Ultrastructure and Purification of Isolated Plant Mitochondria 1

    PubMed Central

    Baker, James E.; Elfvin, Lars-G.; Biale, Jacob B.; Honda, S. I.

    1968-01-01

    Sweetpotato mitochondria, that showed respiratory control, were studied with respect to ultrastructure. If fixed in media containing sucrose at 0.4 M, the cristae were dilated and the matrix was highly condensed. A more orthodox ultrastructural form was observed when the mitochondria were fixed in a medium containing sucrose at 0.25 M, i.e., the matrix was more expanded, the cristae were less dilated, and peripherally, the inner membrane element lay adjacent to the outer membrane element. These results are discussed in terms of a sucrose-accessible space (space between outer and inner membrane elements including intracristal space), and a space relatively inaccessible to sucrose (matrix). Ultrastructural shifts were not observed with change in metabolic steady state of the mitochondria. High resolution electron micrographs showed that the ultrastructure of sweetpotato mitochondria is very similar to that of animal mitochondria. Purity and homogeneity of mitochondrial fractions were followed both by phase-contrast and electron microscopy. Preparations from sweetpotato, using older methods, were relatively homogeneous with respect to particle type and size, whereas avocado preparations contained a high proportion of chloroplasts and cellular debris. A method of purification involving sucrose-density-gradient centrifugation was developed. Purified mitochondria exhibited respiratory control and appeared similar to unpurified mitochondria under the electron microscope. Images PMID:16657002

  9. Aerobic glycolysis: beyond proliferation.

    PubMed

    Jones, William; Bianchi, Katiuscia

    2015-01-01

    Aerobic glycolysis has been generally associated with cancer cell proliferation, but fascinating and novel data show that it is also coupled to a series of further cellular functions. In this Mini Review, we will discuss some recent findings to illustrate newly defined roles for this process, in particular in non-malignant cells, supporting the idea that metabolism can be considered as an integral part of cellular signaling. Consequently, metabolism should be regarded as a plastic and highly dynamic determinant of a wide range of cellular specific functions.

  10. Motility, Survival and Proliferation

    PubMed Central

    Gerthoffer, William T.; Schaafsma, Dedmer; Sharma, Pawan; Ghavami, Saeid; Halayko, Andrew J

    2014-01-01

    Airway smooth muscle has classically been of interest for its contractile response linked to bronchoconstriction. However, terminally differentiated smooth muscle cells are phenotypically plastic and have multifunctional capacity for proliferation, cellular hypertrophy, migration, and the synthesis of extracellular matrix and inflammatory mediators. These latter properties of airway smooth muscle are important in airway remodeling which is a structural alteration that compounds the impact of contractile responses on limiting airway conductance. In this overview we describe the important signaling components and the functional evidence supporting a view of smooth muscle cells at the core of fibroproliferative remodeling of hollow organs. Signal transduction components and events are summarized that control the basic cellular processes of proliferation, cell survival, apoptosis and cellular migration. We delineate known intracellular control mechanisms and suggest future areas of interest to pursue to more fully understand factors that regulate normal myocyte function and airway remodeling in obstructive lung diseases. PMID:23728975

  11. Ultrastructural lesions induced by neptunium-237: apoptosis or necrosis?

    PubMed

    Pusset, D; Fromm, M; Poncy, J L; Kantelip, B; Galle, P; Chambaudet, A; Baud, M; Boulahdour, H

    2002-07-01

    In this study, we are concerned with the 237 isotope of neptunium (237Np), which is a by-product of uranium in nuclear reactors. To study ultrastructural lesions induced by this element, a group of rats were injected with a solution of 237Np-nitrate once a day for 14 weeks. Lesions observed in liver and kidney are described using electron microscopy. Ultrastructural alterations of cellular membranes and intracellular organelles demonstrated the existence of neptunium toxicity. This toxicity was characterized by various lesions, such as cytoplasmic clarification, disappearance of mitochondrial cristae, swollen mitochondria, abnormal condensation of nuclear chromatin, and nuclear fragmentations. This study demonstrated the probable induction of apoptosis by neptunium both in liver and kidneys.

  12. Comparative sperm ultrastructure in Nemertea.

    PubMed

    von Döhren, J; Beckers, P; Vogeler, R; Bartolomaeus, T

    2010-07-01

    Although the monophyly of Nemertea is strongly supported by unique morphological characters and results of molecular phylogenetic studies, their ingroup relationships are largely unresolved. To contribute solving this problem we studied sperm ultrastructure of 12 nemertean species that belong to different subtaxa representing the commonly recognized major monophyletic groups. The study yielded a set of 26 characters with an unexpected variation among species of the same genus (Tubulanus and Procephalothrix species), whereas other species varied in metric values or only one character state (Ramphogordius). In some species, the sperm nucleus has grooves (Zygonemertes virescens, Amphiporus imparispinosus) that may be twisted and give a spiral shape to the sperm head (Paranemertes peregrina, Emplectonema gracile). To make the characters from sperm ultrastructure accessible for further phylogenetic analyses, they were coded in a character matrix. Published data for eight species turned out to be sufficiently detailed to be included. Comparative evaluation of available information on the sperm ultrastructure suggests that subtaxa of Heteronemertea and Hoplonemertea are supported as monophyletic by sperm morphology. However, the data do not provide information on the existing contradictions regarding the internal relationships of "Palaeonemertea." Nevertheless, our study provides evidence that sperm ultrastructure yields numerous potentially informative characters that will be included in upcoming phylogenetic analyses.

  13. Biochemical and Ultrastructural Changes in the Hepatopancreas of Bellamya aeruginosa (Gastropoda) Fed with Toxic Cyanobacteria

    PubMed Central

    Zhu, Jinyong; Lu, Kaihong; Zhang, Chunjing; Liang, Jingjing; Hu, Zhiyong

    2011-01-01

    This study was conducted to investigate ultrastructural alterations and biochemical responses in the hepatopancreas of the freshwater snail Bellamya aeruginosa after exposure to two treatments: toxic cyanobacterium (Microcystis aeruginosa) and toxic cyanobacterial cells mixed with a non-toxic green alga (Scendesmus quadricauda) for a period of 15 days of intoxication, followed by a 15-day detoxification period. The toxic algal suspension induced a very pronounced increase of the activities of acid phosphatases, alkaline phosphatases and glutathione S-transferases (ACP, ALP and GST) in the liver at the later stage of intoxication. During the depuration, enzymatic activity tended to return to the levels close to those in the control. The activity of GST displayed the most pronounced response among different algal suspensions. Severe cytoplasmic vacuolization, condensation and deformation of nucleus, dilation and myeloid-like in mitochondria, disruption of rough endoplasmic reticulum, proliferation of lysosome, telolysosomes and apoptotic body were observed in the tissues. All cellular organelles began recovery after the snails were transferred to the S. quadricauda. The occurrence of a large amount of activated lysosomes and heterolysosomes and augment in activity of detoxification enzyme GST might be an adaptive mechanism to eliminate or lessen cell damage caused by hepatotoxicity to B. aeruginosa. PMID:22125458

  14. A critical role for the peroxisome proliferator-activated receptor alpha (PPARalpha) in the cellular fasting response: the PPARalpha-null mouse as a model of fatty acid oxidation disorders.

    PubMed

    Leone, T C; Weinheimer, C J; Kelly, D P

    1999-06-22

    We hypothesized that the lipid-activated transcription factor, the peroxisome proliferator-activated receptor alpha (PPARalpha), plays a pivotal role in the cellular metabolic response to fasting. Short-term starvation caused hepatic steatosis, myocardial lipid accumulation, and hypoglycemia, with an inadequate ketogenic response in adult mice lacking PPARalpha (PPARalpha-/-), a phenotype that bears remarkable similarity to that of humans with genetic defects in mitochondrial fatty acid oxidation enzymes. In PPARalpha+/+ mice, fasting induced the hepatic and cardiac expression of PPARalpha target genes encoding key mitochondrial (medium-chain acyl-CoA dehydrogenase, carnitine palmitoyltransferase I) and extramitochondrial (acyl-CoA oxidase, cytochrome P450 4A3) enzymes. In striking contrast, the hepatic and cardiac expression of most PPARalpha target genes was not induced by fasting in PPARalpha-/- mice. These results define a critical role for PPARalpha in a transcriptional regulatory response to fasting and identify the PPARalpha-/- mouse as a potentially useful murine model of inborn and acquired abnormalities of human fatty acid utilization.

  15. Inhibition of Lon blocks cell proliferation, enhances chemosensitivity by promoting apoptosis and decreases cellular bioenergetics of bladder cancer: potential roles of Lon as a prognostic marker and therapeutic target in baldder cancer

    PubMed Central

    Wang, Rongrong; Xu, Cuicui; Shi, Yang; Wu, Xiaoyi; Wu, Zhi; Zhang, Jiliang; Chen, Lin; Wang, Lu; Yu, Xiaomin; Zhu, Haibo; Lu, Bin

    2014-01-01

    ATP-dependent Lon protease within mitochondrial matrix contributes to the degradation of abnormal proteins. The oxidative or hypoxic stress which represents the stress phenotype of cancer leads to up-regulation of Lon. However, the role of Lon in bladder cancer remains undefined. Here, we found that Lon expression in bladder cancer tissues was significantly higher than those in noncancerous tissues; down-regulation of Lon in bladder cancer cells significantly blocked cancer cell proliferation via suppression c-Jun N-terminal kinase (JNK) phosphorylation due to decreased reactive oxygen species (ROS) production and enhanced the sensitivity of bladder cancer cells to chemotherapeutic agents by promoting apoptosis. We further found that Lon down-regulation in bladder cancer cells decreased cellular bioenergetics as determined by measuring aerobic respiration and glycolysis using extracellular flux analyzer. The tissue microarray (TMA) results showed that high expression of Lon was related to the T and TNM stage, as well as histological grade of bladder cancer patients. We also demonstrated that Lon was an independent prognostic factor for overall survival of bladder cancer. Taken together, our data suggest that Lon could serve as a potential diagnostic biomarker and therapeutic target for treatment of bladder cancer, as well as for prediction of the effectiveness of chemotherapy. PMID:25526030

  16. [Two cases of sellar chordomas. Ultrastructural and histochemical study (author's transl)].

    PubMed

    Pluot, M; Bernard, M H; Rousseaux, P; Scherpereel, B; Roth, A; Caulet, T

    Two cases of sellar chordomas are reported, with ultrastructural and histochemical study. The embryological origin and the histochemical data are discussed. The question of chondroid chordomas is evoked and the results of the ultrastructural study are interpreted on the basis of the cases hitherto reported. Special attention is called to the methods for the detection of polysaccharides by electron microscopy in such proliferations. Tissue culture seems to be able of providing a good information as to the secretory activity of the chordomas located at the skull base.

  17. Ultrastructure of a magnetotactic spirillum.

    PubMed Central

    Balkwill, D L; Maratea, D; Blakemore, R P

    1980-01-01

    The ultrastructure of a magnetotactic bacterium (strain MS-1) was examined by transmission, scanning, and scanning-transmission electron microscopy. The organism resembled other spirilla in general cell morphology, although some differences were detected at the ultrastructural level. Electron-dense particles within magnetotactic cells were shown by energy-dispersive X-ray analysis to be localizations containing iron. A non-magnetotactic variant of strain MS-1 lacked these novel bacterial inclusion bodies. A chain of these particles traversed each magnetotactic cell in a specific arrangement that was consistent from cell to cell, seemingly associated with the inner surface of the cytoplasmic membrane. Each particle was surrounded by an electron-dense layer separated from the particle surface by an electron-transparent region. The term "magnetosome" is proposed for the electron-dense particles with their enveloping layer(s) as found in this and other magnetotactic bacteria. Images PMID:6245069

  18. Imaging Cellular Proliferation During Chemo-Radiotherapy: A Pilot Study of Serial {sup 18}F-FLT Positron Emission Tomography/Computed Tomography Imaging for Non-Small-Cell Lung Cancer

    SciTech Connect

    Everitt, Sarah; Hicks, Rodney J.; Ball, David; Kron, Tomas; Schneider-Kolsky, Michal; Walter, Tania; Binns, David; Mac Manus, Michael

    2009-11-15

    Purpose: To establish whether {sup 18}F-3'-deoxy-3'-fluoro-L-thymidine ({sup 18}F-FLT) can monitor changes in cellular proliferation of non-small-cell lung cancer (NSCLC) during radical chemo-radiotherapy (chemo-RT). Methods and Materials: As part of a prospective pilot study, 5 patients with locally advanced NSCLC underwent serial {sup 18}F-FLT positron emission tomography (PET)/computed tomography (CT) scans during treatment. Baseline {sup 18}F-FLT PET/CT scans were compared with routine staging {sup 18}F-FDG PET/CT scans. Two on-treatment {sup 18}F-FLT scans were performed for each patient on Days 2, 8, 15 or 29, providing a range of time points for response assessment. Results: In all 5 patients, baseline lesional uptake of {sup 18}F-FLT on PET/CT corresponded to staging {sup 18}F-FDG PET/CT abnormalities. {sup 18}F-FLT uptake in tumor was observed on five of nine (55%) on-treatment scans, on Days 2, 8 and 29, but not Day 15. A 'flare' of {sup 18}F-FLT uptake in the primary tumor of one case was observed after 2 Gy of radiation (1.22 x baseline). The remaining eight on-treatment scans demonstrated a mean reduction in {sup 18}F-FLT tumor uptake of 0.58 x baseline. A marked reduction of {sup 18}F-FLT uptake in irradiated bone marrow was observed for all cases. This reduction was observed even after only 2 Gy, and all patients demonstrated a complete absence of proliferating marrow after 10 Gy. Conclusions: This proof of concept study indicates that {sup 18}F-FLT uptake can monitor the distinctive biologic responses of epithelial cancers and highly radiosensitive normal tissue changes during radical chemo-RT. Further studies of {sup 18}F-FLT PET/CT imaging during therapy may suggest that this tracer is useful in developing response-adapted RT for NSCLC.

  19. Ultrastructure Processing of Macromolecular Materials

    DTIC Science & Technology

    1993-06-25

    Amherst, MA 01003 I U 93 12 6032 n FINAL TECHNICAL REPORT ULTRASTRUCTURE PROCESSING OF MACROMOLECULARI MATERIALS MIRP GRANT AFOSR 90-C-0019 10 February...members of the Directorate, for their unfailing cooperation, help and courtesy extended to him during the period of this grant.I U I I i DTIC qu1...I. TITLE II. PRINCIPAL INVESTIGATOR III. GRANT NUMBERS/DATES I IV. SENIOR RESEARCH PERSONNEL V. JUNIOR RESEARCH PERSONNEL VI . ABSTRACT OF

  20. Characterization of Septin Ultrastructure in Budding Yeast Using Electron Tomography

    PubMed Central

    Bertin, Aurélie; Nogales, Eva

    2015-01-01

    Summary Septins are essential for the completion of cytokinesis. In budding yeast, Saccharomyces cerevisiae, septins are located at the bud neck during mitosis and are closely connected to the inner plasma membrane. In vitro, yeast septins have been shown to self-assemble into a variety of filamentous structures, including rods, paired filaments, bundles and rings [1–3]. Using electron tomography of freeze-substituted section and cryo-electron tomography of frozen sections, we determined the three dimensional organization of the septin cytoskeleton in dividing budding yeast with molecular resolution [4,5]. Here we describe the detailed procedures used for our characterization of the septin cellular ultrastructure. PMID:26519309

  1. Seed Germination and Seedling Growth under Simulated Microgravity Causes Alterations in Plant Cell Proliferation and Ribosome Biogenesis

    NASA Astrophysics Data System (ADS)

    Matía, Isabel; van Loon, Jack W. A.; Carnero-Díaz, Eugénie; Marco, Roberto; Medina, Francisco Javier

    2009-01-01

    The study of the modifications induced by altered gravity in functions of plant cells is a valuable tool for the objective of the survival of terrestrial organisms in conditions different from those of the Earth. We have used the system "cell proliferation-ribosome biogenesis", two inter-related essential cellular processes, with the purpose of studying these modifications. Arabidopsis seedlings belonging to a transformed line containing the reporter gene GUS under the control of the promoter of the cyclin gene CYCB1, a cell cycle regulator, were grown in a Random Positioning Machine, a device known to accurately simulate microgravity. Samples were taken at 2, 4 and 8 days after germination and subjected to biometrical analysis and cellular morphometrical, ultrastructural and immunocytochemical studies in order to know the rates of cell proliferation and ribosome biogenesis, plus the estimation of the expression of the cyclin gene, as an indication of the state of cell cycle regulation. Our results show that cells divide more in simulated microgravity in a Random Positioning Machine than in control gravity, but the cell cycle appears significantly altered as early as 2 days after germination. Furthermore, higher proliferation is not accompanied by an increase in ribosome synthesis, as is the rule on Earth, but the functional markers of this process appear depleted in simulated microgravity-grown samples. Therefore, the alteration of the gravitational environmental conditions results in a considerable stress for plant cells, including those not specialized in gravity perception.

  2. Ultrastructural apoptotic lesions induced in bone marrow after neptunium-237 contamination.

    PubMed

    Pusset, D; Boulahdour, H; Fromm, M; Poncy, J L; Kantelip, B; Griffond, B; Baud, M; Galle, P

    2003-01-01

    This study describes the ultrastructure of lesions induced by neptunium-237 (237Np), a by-product of uranium in nuclear reactors, in the bone marrow. A group of rats were given a single injection of 237Np-nitrate solution in order to observe the acute toxicity effects of this actinide. Electron microscopy was used to describe the different lesions. Observations included the swelling of the cell membrane, nuclear membrane lyses, abnormal chromatin condensation or nucleus convolution. These ultrastructural alterations of the nucleus and the cellular membrane appeared shortly after treatment. This study demonstrates the toxic effects of neptunium and its implication in the induction of apoptosis in bone marrow.

  3. Functional ultrastructure of the plant nucleolus.

    PubMed

    Stępiński, Dariusz

    2014-11-01

    Nucleoli are nuclear domains present in almost all eukaryotic cells. They not only specialize in the production of ribosomal subunits but also play roles in many fundamental cellular activities. Concerning ribosome biosynthesis, particular stages of this process, i.e., ribosomal DNA transcription, primary RNA transcript processing, and ribosome assembly proceed in precisely defined nucleolar subdomains. Although eukaryotic nucleoli are conservative in respect of their main function, clear morphological differences between these structures can be noticed between individual kingdoms. In most cases, a plant nucleolus shows well-ordered structure in which four main ultrastructural components can be distinguished: fibrillar centers, dense fibrillar component, granular component, and nucleolar vacuoles. Nucleolar chromatin is an additional crucial structural component of this organelle. Nucleolonema, although it is not always an unequivocally distinguished nucleolar domain, has often been described as a well-grounded morphological element, especially of plant nucleoli. The ratios and morphology of particular subcompartments of a nucleolus can change depending on its metabolic activity which in turn is correlated with the physiological state of a cell, cell type, cell cycle phase, as well as with environmental influence. Precise attribution of functions to particular nucleolar subregions in the process of ribosome biosynthesis is now possible using various approaches. The presented description of plant nucleolar morphology summarizes previous knowledge regarding the function of nucleoli as well as of their particular subdomains not only in the course of ribosome biosynthesis.

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

    PubMed Central

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

    2016-01-01

    Study Objective: The adolescent brain may be uniquely affected by acute sleep deprivation (ASD) and chronic sleep restriction (CSR), but direct evidence is lacking. We used electron microscopy to examine how ASD and CSR affect pyramidal neurons in the frontal cortex of adolescent mice, focusing on mitochondria, endosomes, and lysosomes that together perform most basic cellular functions, from nutrient intake to prevention of cellular stress. Methods: Adolescent (1-mo-old) mice slept (S) or were sleep deprived (ASD, with novel objects and running wheels) during the first 6–8 h of the light period, chronically sleep restricted (CSR) for > 4 days (using novel objects, running wheels, social interaction, forced locomotion, caffeinated water), or allowed to recover sleep (RS) for ∼32 h after CSR. Ultrastructural analysis of 350 pyramidal neurons was performed (S = 82; ASD = 86; CSR = 103; RS = 79; 4 to 5 mice/group). Results: Several ultrastructural parameters differed in S versus ASD, S versus CSR, CSR versus RS, and S versus RS, although the different methods used to enforce wake may have contributed to some of the differences between short and long sleep loss. Differences included larger cytoplasmic area occupied by mitochondria in CSR versus S, and higher number of secondary lysosomes in CSR versus S and RS. We also found that sleep loss may unmask interindividual differences not obvious during baseline sleep. Moreover, using a combination of 11 ultrastructural parameters, we could predict in up to 80% of cases whether sleep or wake occurred at the single cell level. Conclusions: Ultrastructural analysis may be a powerful tool to identify which cellular organelles, and thus which cellular functions, are most affected by sleep and sleep loss. Citation: de Vivo L, Nelson AB, Bellesi M, Noguti J, Tononi G, Cirelli C. Loss of sleep affects the ultrastructure of pyramidal neurons in the adolescent mouse frontal cortex. SLEEP 2016;39(4):861–874. PMID:26715225

  5. Non-cross-linked collagen type I/III materials enhance cell proliferation: in vitro and in vivo evidence

    PubMed Central

    WILLERSHAUSEN, Ines; BARBECK, Mike; BOEHM, Nicole; SADER, Robert; WILLERSHAUSEN, Brita; KIRKPATRICK, Charles James; GHANAATI, Shahram

    2014-01-01

    Objective To analyze Mucograft®(MG), a recently introduced collagen matrix, in vitro and in vivo, and compare it with BioGide®(BG), a well-established collagen membrane, as control. Material and Methods A detailed analysis of the materials surface and ultra-structure was performed. Cellular growth patterns and proliferation rates of human fibroblasts on MG and BG were analyzed in vitro. In addition, the early tissue reaction of CD-1 mouse to these materials was analyzed by means of histological and histomorphometrical analysis. Results MG showed a three-fold higher thickness both in dry and wet conditions, when compared to BG. The spongy surface of BG significantly differed from that of MG. Cells showed a characteristic proliferation pattern on the different materials in vitro. Fibroblasts tended to proliferate on the compact layers of both collagens, with the highest values on the compact side of BG. In vivo, at day three both materials demonstrated good tissue integration, with a mononuclear cell sheet of fibroblasts on all surfaces, however, without penetrating into the materials. Conclusions The findings of this study showed that MG and BG facilitate cell proliferation on both of their surfaces in vitro. In vivo, these two materials induce a comparable early tissue reaction, while serving as cell occlusive barriers. PMID:24626246

  6. Electron microscopy for ultrastructural analysis and protein localization in Saccharomyces cerevisiae

    PubMed Central

    Frankl, Andri; Mari, Muriel; Reggiori, Fulvio

    2015-01-01

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

  7. Ultrastructural researches on rabbit myxomatosis. Lymphnodal lesions.

    PubMed

    Marcato, P S; Simoni, P

    1977-07-01

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

  8. Histologic and ultrastructural characterization of corneal femtosecond laser trephination.

    PubMed

    Nuzzo, Valeria; Aptel, Florent; Savoldelli, Michèle; Plamann, Karsten; Peyrot, Donald; Deloison, Florent; Donate, David; Legeais, Jean-Marc

    2009-09-01

    The purpose of this study was to evaluate the quality of femtosecond laser corneal trephination in eye bank eyes by histologic and ultrastructural investigation. We performed Z-shaped, tophat-shaped, and mushroom-shaped trephinations of swelled corneas from eye bank eyes using an Intralase FS60 system. The corneoscleral discs were fixed immediately after the laser procedure without removing the buttons. Thin and ultrathin tissue sections were examined by light and transmission electron microscopy. Optical micrographs of the corneal tissue revealed that the femtosecond laser was efficient in producing Z-shaped, tophat-shaped, and mushroom-shaped dissections with reproducible high cut regularity. Investigations by transmission electron microscopy demonstrated that cut edges were of good quality devoid of thermal or mechanical damage of the adjacent tissues. However, cellular and collagenous nanometric debris was created by the laser. In the anterior stroma, they formed a layer of several microns in thickness residing on the terminated disrupted collagen fibers, whereas in the posterior stroma, they formed a thinner pseudomembrane running along the edges of the incision. Corneal trephination performed by the femtosecond laser preserves the ultrastructure of the disrupted collagen fibers. In edematous corneas, a layer of cellular and collagenic debris thicker in the anterior stroma and thinner in the posterior stroma runs along the edges of the incision obtained at a constant laser energy density.

  9. So-called embryonal hyperplasia of Bowman's capsular epithelium: an immunohistochemical and ultrastructural study.

    PubMed

    Ogata, K; Hajikano, H; Sakaguchi, H

    1991-01-01

    The so-called embryonal hyperplasia of Bowman's capsular epithelium (EHBCE) is a rather specific lesion occurring in kidneys of patients maintained on chronic dialysis. It consists of poorly differentiated cells proliferating around sclerosed or obsolescent glomeruli. In this study, immunohistochemical and ultrastructural characterization of EHBCE was performed. The poorly differentiated cells in the lesion exhibited a positive reaction for vimentin and a negative one for cytokeratin (PKK 1) and epithelial membrane antigen. On ultrastructural examination, specialized junctions between adjoining cells, microvilli-like structures on their surfaces, and immature basal folds were observed. These observations suggest that the cells of EHBCE may be associated with the anlage of glomerular epithelium. The background in which neoplasms like renal cell carcinoma or atypical epithelium of cyst wall develop in end-stage kidneys of adult patients on long-term dialysis may cause such a proliferation of poorly differentiated cells in young or paediatric age group patients.

  10. Platelet satellitism: an ultrastructural study.

    PubMed Central

    Payne, C. M.

    1981-01-01

    The ultrastructural morphology of platelet-polymorph (platelet-polymorphonuclear leukocyte) rosettes was investigated in EDTA-anticoagulated blood obtained from two patients who exhibited the phenomenon of platelet satellitism. Most of the platelet profiles were attached to the polymorph surface by broad areas of contact. Examination of these broad areas of contact at high magnification revealed an intercellular material of low electron density. This material appeared to form strands, which bridged the intercellular space and spanned the entire area formed by the apposing plasma membranes. Phagocytosis of entire platelets was only observed in 1 case. The platelet profiles that participated in rosette formation revealed a large number of glycogen particles, compared with unattached platelets. Ultrastructural examination of "stress" platelets obtained from five normal subjects treated with steroids similarly showed a large number of glycogen particles, although no rosette formation or phagocytosis of platelets was observed. The etiology of platelet satellitism is discussed. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:7223859

  11. Lymphocytic Oesophagitis Preliminary Ultrastructural Observations.

    PubMed

    Rubio, Carlos A; Villnow, Elisabeth; Schmidt, Peter T

    2016-05-01

    Lymphocytic oesophagitis (LyE) is a newly described entity characterized by a high number of intraepithelial lymphocytes/ high power field (≥40 CD3+IELs/HPF) in the oesophageal epithelium. The aim of the study was to investigate possible ultrastructural changes taking place in LyE at the transmission electron microscopic (TEM) level. Oesopageal biopsies from seven patients were investigated: four were consecutive patients with LyE, one with reflux oesopagitis, one with eosinophilic oesopagitis (EoE) and one with histologically normal squamous epithelium. In LyE, marked intercellular oedema (spongiosis) and a gamut of regressive changes were found in squamous cells, ranging from cytoplasmic oedema and vacuolization, to total cell disintegration. IELs also showed regressive changes ranging from ballooned, oedematous cytoplasm to signs of intracytoplasmatic disintegration. Besides hampered cell nutrition conveyed by spongiosis, putative noxious molecules contained in the intercellular spongiotic oedema might account for the dramatic TEM alterations found in LyE. The present findings provide, for the first time, "inside information" on the ultrastructural alterations taking place in LyE, both in squamous cells and in IELs. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

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

    PubMed

    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.

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

    PubMed Central

    Omi, Tokuya; Sato, Shigeru; Kawana, Seiji

    2013-01-01

    Introduction and Aims: 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. Subjects and Methods: 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. Results: 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. Conclusions: 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. PMID:24155558

  14. Salivary gland monomorphic adenoma. Ultrastructural, immunoperoxidase, and histogenetic aspects.

    PubMed Central

    Dardick, I.; Kahn, H. J.; Van Nostrand, A. W.; Baumal, R.

    1984-01-01

    Monomorphic adenoma of basal cell type is a salivary gland tumor believed to result from a proliferation of a single type of cell. However, ultrastructural and immunocytochemical investigations of 6 monomorphic adenomas (5 from parotid and 1 from intraoral minor salivary gland) indicate that there are two classes of these lesions, one composed of two types of tumor cells and the other wholly or predominantly made up of one type of cell (isomorphic). In the former group, the organization of the tumor cells closely mimicked that of normal and hyperplastic salivary gland intercalated ducts. Aggregates of tumor cells were arranged as an inner layer of luminal epithelial cells which were surrounded by an outer layer of cells that, in some cases, had ultrastructural and immunohistochemical features indicating myoepithelial cell differentiation. In some adenomas formed by two types of tumor cells, basal-lamina-lined extracellular spaces were identified ultrastructurally in relation to modified myoepithelial cells; such spaces had the same fine-structural features as those reported in pleomorphic adenoma and adenoid cystic carcinoma. Predominantly isomorphic adenomas were composed exclusively of luminal epithelial cells. These results indicate that despite the varied histologic patterns in the numerous subtypes of monomorphic adenoma, there is a central theme of differentiation and organization in this type of neoplasm which recapitulates the ductoacinar unit of normal salivary gland parenchyma. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 PMID:6375388

  15. 18F-FDG labeling of mesenchymal stem cells and multipotent adult progenitor cells for PET imaging: effects on ultrastructure and differentiation capacity.

    PubMed

    Wolfs, Esther; Struys, Tom; Notelaers, Tineke; Roberts, Scott J; Sohni, Abhishek; Bormans, Guy; Van Laere, Koen; Luyten, Frank P; Gheysens, Olivier; Lambrichts, Ivo; Verfaillie, Catherine M; Deroose, Christophe M

    2013-03-01

    Because of their extended differentiation capacity, stem cells have gained great interest in the field of regenerative medicine. For the development of therapeutic strategies, more knowledge on the in vivo fate of these cells has to be acquired. Therefore, stem cells can be labeled with radioactive tracer molecules such as (18)F-FDG, a positron-emitting glucose analog that is taken up and metabolically trapped by the cells. The aim of this study was to optimize the radioactive labeling of mesenchymal stem cells (MSCs) and multipotent adult progenitor cells (MAPCs) in vitro with (18)F-FDG and to investigate the potential radiotoxic effects of this labeling procedure with a range of techniques, including transmission electron microscopy (TEM). Mouse MSCs and rat MAPCs were used for (18)F-FDG uptake kinetics and tracer retention studies. Cell metabolic activity, proliferation, differentiation and ultrastructural changes after labeling were evaluated using an Alamar Blue reagent, doubling time calculations and quantitative TEM, respectively. Additionally, mice were injected with MSCs and MAPCs prelabeled with (18)F-FDG, and stem cell biodistribution was investigated using small-animal PET. The optimal incubation period for (18)F-FDG uptake was 60 min. Significant early tracer washout was observed, with approximately 30%-40% of the tracer being retained inside the cells 3 h after labeling. Cell viability, proliferation, and differentiation capacity were not severely affected by (18)F-FDG labeling. No major changes at the ultrastructural level, considering mitochondrial length, lysosome size, the number of lysosomes, the number of vacuoles, and the average rough endoplasmic reticulum width, were observed with TEM. Small-animal PET experiments with radiolabeled MAPCs and MSCs injected intravenously in mice showed a predominant accumulation in the lungs and a substantial elution of (18)F-FDG from the cells. MSCs and MAPCs can be successfully labeled with (18)F-FDG for

  16. Effects of long-term administration of the antiepileptic drug--sodium valproate upon the ultrastructure of hepatocytes in rats.

    PubMed

    Sobaniec-Lotowska, M E

    1997-08-01

    Chronic intragastric application (1, 3, 6, 9 and 12 months) of the antiepileptic drug--sodium valproate (VPA; Vupral "Polfa") to rats in the effective dose of 200 mg/kg b.w./day exerts hepatotoxic effect after 9 and 12 months of the experiment. The first ultrastructural changes in hepatocytes were observed after 3 months of the drug administration. These became more intense in the subsequent stages of the experiment, to be most pronounced after 12 months. The most striking changes were in the mitochondria (significant swelling, an increase in their number, degeneration of matrix and cristae, disruption of the outer mitochondrial membrane) and in peroxisomes (proliferation, enlargement and the presence of distinct nucleoids). Further alterations in hepatocytes manifested themselves in: microvesicular fatty change with cholesterolosis (cholesterol clefts), damage to the cellular membrane of the sinusoidal pole with dilation of the perisinusoidal space of Disse, presence of cystern-like cytoplasmic vacuoles in the sinusoidal region, filled with plasma-like material and focal cytoplasmic necrosis. The changes in hepatocytes coexisted with the swelling and activation of sinusoidal cells, endothelial cells and Kupffer cells. The author suggests that mitochondria and peroxisomes considerably contribute to the morphogenesis of hepatocyte damage by VPA in the chronic experimental model.

  17. Ultrastructure of intestinal cells of Heterakis gallinarum.

    PubMed

    Zmoray, I; Gutteková, A

    1978-06-01

    Ultrastructure of intestinal cells of Heterakis gallinarum is described and compared with that of Ascaridia galli from ecomorphological point of view. The great analogy in bionomy and ecology of both worms is reflected in the great analogy of ultrastructural construction. A new organoid in the intestinal cells of H. gallinarum, hitherto unknown among nematodes, is also described. It is of a vacuole-like shape running in stripes close under the terminal bar. The paper is also meant to be a supplement to the authors' previous paper (1975) dealing with ultrastructure of muscle cells of Heterakis gallinarum.

  18. Ultrastructural analysis of Candida albicans when exposed to silver nanoparticles.

    PubMed

    Vazquez-Muñoz, Roberto; Avalos-Borja, Miguel; Castro-Longoria, Ernestina

    2014-01-01

    Candida albicans is the most common fungal pathogen in humans, and recently some studies have reported the antifungal activity of silver nanoparticles (AgNPs) against some Candida species. However, ultrastructural analyses on the interaction of AgNPs with these microorganisms have not been reported. In this work we evaluated the effect of AgNPs on C. albicans, and the minimum inhibitory concentration (MIC) was found to have a fungicidal effect. The IC50 was also determined, and the use of AgNPs with fluconazole (FLC), a fungistatic drug, reduced cell proliferation. In order to understand how AgNPs interact with living cells, the ultrastructural distribution of AgNPs in this fungus was determined. Transmission electron microscopy (TEM) analysis revealed a high accumulation of AgNPs outside the cells but also smaller nanoparticles (NPs) localized throughout the cytoplasm. Energy dispersive spectroscopy (EDS) analysis confirmed the presence of intracellular silver. From our results it is assumed that AgNPs used in this study do not penetrate the cell, but instead release silver ions that infiltrate into the cell leading to the formation of NPs through reduction by organic compounds present in the cell wall and cytoplasm.

  19. Ultrastructural Analysis of Candida albicans When Exposed to Silver Nanoparticles

    PubMed Central

    Vazquez-Muñoz, Roberto; Avalos-Borja, Miguel; Castro-Longoria, Ernestina

    2014-01-01

    Candida albicans is the most common fungal pathogen in humans, and recently some studies have reported the antifungal activity of silver nanoparticles (AgNPs) against some Candida species. However, ultrastructural analyses on the interaction of AgNPs with these microorganisms have not been reported. In this work we evaluated the effect of AgNPs on C. albicans, and the minimum inhibitory concentration (MIC) was found to have a fungicidal effect. The IC50 was also determined, and the use of AgNPs with fluconazole (FLC), a fungistatic drug, reduced cell proliferation. In order to understand how AgNPs interact with living cells, the ultrastructural distribution of AgNPs in this fungus was determined. Transmission electron microscopy (TEM) analysis revealed a high accumulation of AgNPs outside the cells but also smaller nanoparticles (NPs) localized throughout the cytoplasm. Energy dispersive spectroscopy (EDS) analysis confirmed the presence of intracellular silver. From our results it is assumed that AgNPs used in this study do not penetrate the cell, but instead release silver ions that infiltrate into the cell leading to the formation of NPs through reduction by organic compounds present in the cell wall and cytoplasm. PMID:25290909

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

    PubMed

    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.

  1. [Asteroid hyalopathy. Ultrastructural study of 3 cases].

    PubMed

    Adenis, J P; Leboutet, M J; Loubet, R

    1984-01-01

    The vitreous of three patients with asteroïd hyalosis (average age: 57 years) was obtained by a two-hand closed pars plana vitrectomy. Asteroïd hyalosis was associated with alcoholic neuropathy in the first case, long standing retinal detachment in the second case, and diabetes mellitus in the third case. The visual acuity before and after the surgical procedure improved from 1.2/6 to 6/6 in the first case, from light perception to 0.3/6 in the second case, from 0.6/6 to 4.8/6 in the third case. The vitreous was studied by different ultrastructural technics : transmission electron microscopy (T.E.M.) scanning electron microscopy (S.E.M.) and electron diffraction X ray analysis (E.D.A.X.). By S.E.M. the asteroïd bodies appeared as rounded structures with an irregular surface connected to each other by fibrous strands among sodium chloride crystals. No cellular remnants were observed. By T.E.M. the asteroïd bodies were composed of interwinned ribbons of multilaminar membranes with a periodicity (10 to 60 A) characteristic of complex lipids, especially phospholipids. At the edge of the ribbons there were dots and sometimes clumps of opaque material that tended to crack out of the specimen with the heat of the electron beam. T.E.M. study disclosed the irregular disposition of the calcific bodies. By E.D.A.X. the calcific composition of the rounded structures could be determined : calcium and phosphorus were the main elements detectable in asteroïd bodies of all sizes for all three patients. The average calcium counts for the three successive cases were : 18, 30, 43 and for phosphorus : 9, 14, 26. Potassium was found in the first case, and sulfur in the third case.(ABSTRACT TRUNCATED AT 250 WORDS)

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

    PubMed

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

    2017-01-01

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

  3. Ultrastructural characteristics of type A epithelioid cells during BCG-granulomatosis and treatment with lysosomotropic isoniazid.

    PubMed

    Shkurupii, V A; Kozyaev, M A; Nadeev, A P

    2006-04-01

    We studied BCG-granulomas, their cellular composition, and ultrastructure of type A epithelioid cells in the liver of male BALB/c mice with spontaneous granulomatous inflammation. The animals received free isoniazid or isoniazid conjugated with lysosomotropic intracellularly prolonged matrix (dialdehyde dextran, molecular weight 65-75 kDa). Lysosomotropic isoniazid was accumulated in the vacuolar apparatus of epithelioid cells and produced a stimulatory effect on plastic processes in these cells.

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

    PubMed

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

    2016-04-01

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

  5. Ultrastructural characterization of normal and abnormal chondrogenesis in micromass rat embryo limb bud cell cultures.

    PubMed

    Renault, J Y; Caillaud, J M; Chevalier, J

    1995-02-01

    Inhibition of chondrogenesis in limb bud cell micromass cultures has been proposed as a short-term teratogen detection test. Validation studies were performed by testing large series of reference compounds and comparing their teratogenic potential with their ability to inhibit chondrogenesis; however, there are few reports describing the histological and ultrastructural changes associated with inhibition of chondrogenesis in vitro. The objective of this study was to provide a qualitative description of the histological and ultrastructural alterations induced by three chondrogenesis inhibitors: retinoic acid (RA) and 6-aminonicotinamide (6AN), two teratogens, and doxylamine succinate (DS), a nonteratogen compound. In addition, in order to have a basis for the interpretation of the morphological alterations induced by the test compounds, the histological and ultrastructural changes which occur during the time course of chondrogenesis in control cultures were described and compared with those in rat embryo limb buds. We found that RA at 0.5 micrograms/ml led to a marked decrease in the number and size of cartilaginous foci; most cells lacked morphological signs of differentiation but their ability to proliferate was unaffected. At concentrations of 2 micrograms/ml and more, 6AN delayed cell proliferation, reduced staining of the extracellular matrix, and induced the formation of endoplasmic cisternae. DS at 50 micrograms/ml affected both differentiation and proliferation; pigment deposits were observed in chondrocytes, suggesting phospholipid metabolism disorders. In conclusion, this study showed that inhibition of chondrogenesis in this simple cell culture system can be associated with different types of histological and ultrastructural alterations. Examination of these alterations can provide useful information about the teratogenic potential of tested compounds and their mechanism of action.

  6. Effect of Hydrofiber wound dressings on bacterial ultrastructure.

    PubMed

    Hobot, Jan; Walker, Michael; Newman, Geoffrey; Bowler, Philip

    2008-04-01

    Ionic silver has well-proven bactericidal properties, and silver-containing wound dressings are now widely used to aid in the creation of an antimicrobial environment in wounds. The effect of silver ions on bacterial ultrastructure can best be studied by viewing bacterial cells under a transmission electron microscope (TEM). Bacterial cells of Pseudomonas aeruginosa were incubated within a control dressing (e.g. a non-antimicrobial Hydrofiber dressing) (Hydrofiber is a registered trademark of E.R. Squibb and Sons, L.L.C.) and a silver-containing Hydrofiber dressing, followed by processing for TEM. Liquid cultures, with and without silver, were prepared for comparison. The addition of silver to growing bacterial cultures stopped growth of the cells very quickly. Ultrastructurally, the presence of silver was found to affect both the shape of the bacterial nucleoid and the organization of bacterial DNA. X-ray microanalysis of bacteria from liquid cultures showed the presence of silver within silver-treated cells and the absence of calcium. It is suggested that the presence of available silver ions within the Hydrofiber dressing could lead to the loss of cellular ions, vital for maintaining the structural integrity of the nuclear area.

  7. Ultrastructural changes of goat corpus luteum during the estrous cycle.

    PubMed

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

    2016-07-01

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

  8. Platelet-derived growth factor activity and mRNA expression in healing vascular grafts in baboons. Association in vivo of platelet-derived growth factor mRNA and protein with cellular proliferation.

    PubMed Central

    Golden, M A; Au, Y P; Kirkman, T R; Wilcox, J N; Raines, E W; Ross, R; Clowes, A W

    1991-01-01

    In a baboon graft model of arterial intimal thickening, smooth muscle cells (SMC) have been observed to proliferate underneath an intact monolayer of endothelium and in the absence of platelet adherence. Because platelets are not present and therefore cannot be a major source of growth stimulus, we have proposed that the vascular wall cells in the graft intima express mitogens and regulate SMC proliferation. To test this hypothesis, we assayed the grafts for mitogenic activity and expression of growth factor genes. Segments of healing graft and of normal artery, when perfused ex vivo, released mitogenic activity into the perfusate. The graft released more mitogen than the normal arterial segment, and some of the activity was inhibitable with an antibody to human platelet-derived growth factor (PDGF). In addition, Northern analysis of total RNA demonstrated higher expression of PDGF-A chain mRNA in the graft intima compared to normal artery. PDGF-B chain mRNA was barely detectable in both tissues. PDGF mRNA levels within the graft interstices were not measured. In situ hybridization of 7.5- or 12-wk grafts indicated that some luminal endothelial cells and adjacent intimal SMC contained PDGF-A chain mRNA. By thymidine autoradiography, intimal SMC were observed to be proliferating in the inner third of the intima. These data demonstrate a difference in the pattern of PDGF transcript expression and luminal perfusate activity in graft as compared with control arteries. The association of intimal smooth muscle cell proliferation with intimal PDGF mRNA expression and release of PDGF-like protein supports the hypothesis that factors from cells that have grown into the graft or populated its surface rather than platelets may regulate intimal smooth muscle cell proliferation in this model. Images PMID:1825089

  9. Ultrastructure of autophagy in plant cells: a review.

    PubMed

    van Doorn, Wouter G; Papini, Alessio

    2013-12-01

    Just as with yeasts and animal cells, plant cells show several types of autophagy. Microautophagy is the uptake of cellular constituents by the vacuolar membrane. Although microautophagy seems frequent in plants it is not yet fully proven to occur. Macroautophagy occurs farther away from the vacuole. In plants it is performed by autolysosomes, which are considerably different from the autophagosomes found in yeasts and animal cells, as in plants these organelles contain hydrolases from the onset of their formation. Another type of autophagy in plant cells (called mega-autophagy or mega-autolysis) is the massive degradation of the cell at the end of one type of programmed cell death (PCD). Furthermore, evidence has been found for autophagy during degradation of specific proteins, and during the internal degeneration of chloroplasts. This paper gives a brief overview of the present knowledge on the ultrastructure of autophagic processes in plants.

  10. Platelets: production, morphology and ultrastructure.

    PubMed

    Thon, Jonathan N; Italiano, Joseph E

    2012-01-01

    Platelets are anucleate, discoid cells, roughly 2-3 μm in diameter that function primarily as regulators of hemostasis, but also play secondary roles in angiogensis and innate immunity. Although human adults contain nearly one trillion platelets in circulation that are turned over every 8-10 days, our understanding of the mechanisms involved in platelet production is still incomplete. Platelets stem from large (30-100 μm) nucleated cells called megakaryocytes that reside primarily in the bone marrow. During maturation megakaryocytes extend long proplatelet elongations into sinusoidal blood vessels from which platelets ultimately release. During this process, platelets develop a number of distinguishable structural elements including: a delimited plasma membrane; invaginations of the surface membrane that form the open canalicular system (OCS); a closed-channel network of residual endoplasmic reticulum that form the dense tubular system (DTS); a spectrin-based membrane skeleton; an actin-based cytoskeletal network; a peripheral band of microtubules; and numerous organelles including α-granules, dense-granules, peroxisomes, lysosomes, and mitochondria. Proplatelet elongation and platelet production is an elaborate and complex process that defines the morphology and ultrastructure of circulating platelets, and is critical in understanding their increasingly numerous and varied biological functions.

  11. Four faces of cellular senescence

    PubMed Central

    Rodier, Francis

    2011-01-01

    Cellular senescence is an important mechanism for preventing the proliferation of potential cancer cells. Recently, however, it has become apparent that this process entails more than a simple cessation of cell growth. In addition to suppressing tumorigenesis, cellular senescence might also promote tissue repair and fuel inflammation associated with aging and cancer progression. Thus, cellular senescence might participate in four complex biological processes (tumor suppression, tumor promotion, aging, and tissue repair), some of which have apparently opposing effects. The challenge now is to understand the senescence response well enough to harness its benefits while suppressing its drawbacks. PMID:21321098

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

    NASA Technical Reports Server (NTRS)

    Moore, R.

    1985-01-01

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

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

    NASA Technical Reports Server (NTRS)

    Moore, R.

    1985-01-01

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

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

    PubMed

    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.

  15. Ultrastructure of preimplantation genetic diagnosis-derived human blastocysts grown in a coculture system after vitrification.

    PubMed

    Escribá, María-José; Escobedo-Lucea, Carmen; Mercader, Amparo; de los Santos, María-José; Pellicer, Antonio; Remohí, José

    2006-09-01

    To evaluate ultrastructural features of preimplantation genetic diagnosis (PGD) blastocysts before and after vitrification. Descriptive study of both vitrified and fresh hatching blastocysts. PGD program at the Instituto Universitario, Instituto Valenciano de Infertilidad. Patients undergoing PGD donated their abnormal embryos for research (n = 26). Biopsied embryos were cultured in the presence of human endometrial cells until day 6. Sixteen blastocysts were vitrified. A total of 11 high-scored hatching blastocysts, 6 warmed and 5 fresh, were fixed for ultrastructure. The cytoskeleton structure, type of intercellular junctions, and basic intracellular organelles in trophoectoderm cells and the inner cell mass were analyzed. Ten of 16 blastocysts (62%) survived the warming process. Six of these showed no signs of cell degeneration and light microscopy revealed similar ultrastructural characteristics to those of controls. However, in trophoectoderm cells from both fresh and cryopreserved blastocysts, a reduced number of tight junctions and the presence of degradation bodies were detected. The particular ultrastructural features observed in PGD-derived blastocysts could be related to embryo manipulation and culture conditions. Vitrification does not seem to alter blastocysts, as those that survive hatching do not display detectable cellular alterations when observed through electron microscopy.

  16. Electron Microscopy Observation of Human Pulmonary Ultrastructure in Two Patients with High-Altitude Pulmonary Edema.

    PubMed

    Droma, Yunden; Kato, Akane; Ichiyama, Takashi; Kobayashi, Nobumitsu; Honda, Takayuki; Uehara, Takeshi; Hanaoka, Masayuki

    2017-09-01

    We examined the pulmonary ultrastructure in tissue from two patients with high-altitude pulmonary edema (HAPE) by electron microscopy. In one case, we found that neutrophils were trapped in pulmonary capillary lumen of alveolar-capillary wall and part of the cytoplasm of a neutrophil protruded and adhered to the capillary endothelium. There were several degranulated vacuoles in the cytoplasm of the neutrophil. The pulmonary capillary wall was deformed, thickened, and swollen and there was evidence of degeneration. In another case, infiltration of neutrophils and macrophages, proliferation of type II pneumocytes, and numerous red blood cells were also observed in alveolar air space. These electron microscopic ultrastructural observations illustrate for the first time damage to the pulmonary alveolar-capillary barrier in lung tissue of humans with advanced HAPE.

  17. Cilia ultrastructure in children with Down syndrome.

    PubMed

    McLean, Laurie; MacCormick, Johnna; Robb, Ian; Carpenter, Blair; Pothos, Mary

    2003-12-01

    Chronic sinusitis, otitis media with effusion, and upper respiratory tract infections are commonly found in patients with Down syndrome. These diseases are generally felt to be secondary to depressed immune function and altered craniofacial dimensions. Recently, a cilia ultrastructure abnormality was found in a child with Down syndrome. This study is the first to be carried out to determine if cilia ultrastructure abnormalities are prevalent in the population with Down syndrome. Four of 10 patients had documented cilia abnormalities, but these were present in the background of normal cilia, suggesting that they were the result rather than the cause of chronic sinusitis. Similarly, nasal epithelium metaplasia was detected in 50% of the patients. Chronic sinusitis, otitis media with effusion, and recurrent upper respiratory tract infections in children with Down syndrome cannot generally be attributed to primary cilia ultrastructure abnormalities.

  18. [Ultrastructural characteristics of glaucomatous trabecular meshwork].

    PubMed

    Potau, J M; Canals, M; Costa, J; Merindano, M D; Ruano, D

    2000-01-01

    To compare the normal and glaucomatous trabecular meshwork ultrastructure and to relate the observed changes with the intraocular pressure increase characteristic of the primary open angle glaucoma. 21 non glaucomatous trabecular meshworks, aged 23 to 99 years, and 5 from patients diagnosed of primary open angle glaucoma, aged 40 to 65 years, were fixed by Karnovsky's solution and processed and observed by transmission electron microscopy and their morphological characteristics were qualitatively compared. Ultrastructural changes of glaucomatous trabecular meshworks are similar, but much more intense, than those observed in the aged normal trabecular meshworks. These changes are loss of endothelial cells, thickening of basal membranes and trabecular beam central nucleus changes such as an increase of electrodense plaques and collagen degenerative processes. Ultrastructural changes observed in glaucomatous trabecular meshworks are comparable to an early aging of them. These changes can be related with the mechanisms that increase the intraocular pressure in primary open-angle glaucoma.

  19. Ultrastructural changes caused by polymyxin B and meropenem in multiresistant Klebsiella pneumoniae carrying blaKPC-2 gene.

    PubMed

    Scavuzzi, Alexsandra Maria Lima; Alves, Luiz Carlos; Veras, Dyana Leal; Brayner, Fábio André; Lopes, Ana Catarina Souza

    2016-12-01

    The ultrastructural alterations caused by polymyxin B and meropenem and by the association between polymyxin B and meropenem were investigated in two multiresistant isolates of Klebsiella pneumoniae (K3-A2 and K12-A2) carriers of blaKPC-2, coming from infection and colonization in patients in a public hospital in Recife, Brazil. The ultrastructural changes were detected by transmission electron microscopy and scanning. The susceptibility of the isolates to antimicrobials was tested by the disc diffusion method and microdilution in broth. The analysis by electron microscopy showed that the isolates presented morphological and ultrastructural cellular changes when subjected to a clinically relevant concentration of antimicrobials alone or in combination. When subjected to meropenem, they presented retraction of the cytoplasmic material, rupture of the cell wall and extravasation of the cytoplasmic content. When submitted to polymyxin B, the isolates showed condensation of the ribosomes, DNA clotting, cell wall thickening and the presence of membrane compartment. When subjected to polymyxin B and meropenem in combination, the isolates showed a higher intensity of the ultrastructural changes visualized. This is the first report of the ultrastructural changes caused by polymyxin B and meropenem in multiresistant isolates of K. pneumoniae carriers of the blaKPC-2 gene. It should be noted that even when the K. pneumoniae isolates were multiresistant carriers of the blaKPC-2 gene, they underwent important structural change owing to the action of polymyxin B and meropenem.

  20. Ultrastructural analysis of the decellularized cornea after interlamellar keratoplasty and microkeratome-assisted anterior lamellar keratoplasty in a rabbit model

    PubMed Central

    Hashimoto, Yoshihide; Hattori, Shinya; Sasaki, Shuji; Honda, Takako; Kimura, Tsuyoshi; Funamoto, Seiichi; Kobayashi, Hisatoshi; Kishida, Akio

    2016-01-01

    The decellularized cornea has received considerable attention for use as an artificial cornea. The decellularized cornea is free from cellular components and other immunogens, but maintains the integrity of the extracellular matrix. However, the ultrastructure of the decellularized cornea has yet to be demonstrated in detail. We investigated the influence of high hydrostatic pressure (HHP) on the decellularization of the corneal ultrastructure and its involvement in transparency, and assessed the in vivo behaviour of the decellularized cornea using two animal transplantation models, in relation to remodelling of collagen fibrils. Decellularized corneas were prepared by the HHP method. The decellularized corneas were executed by haematoxylin and eosin and Masson’s trichrome staining to demonstrate the complete removal of corneal cells. Transmission electron microscopy revealed that the ultrastructure of the decellularized cornea prepared by the HHP method was better maintained than that of the decellularized cornea prepared by the detergent method. The decellularized cornea after interlamellar keratoplasty and microkeratome-assisted anterior lamellar keratoplasty using a rabbit model was stable and remained transparent without ultrastructural alterations. We conclude that the superior properties of the decellularized cornea prepared by the HHP method were attributed to the preservation of the corneal ultrastructure. PMID:27291975

  1. Garlic prevents ultrastructural alterations caused by dehydration in mouse cerebral microvessels.

    PubMed

    Fahim, M A; El-Sabban, F F

    2001-05-01

    Dehydration is known to significantly reduce both the time required for the first platelet aggregate and the time to full occlusion in photochemically-induced thrombosis, in vivo. Ultrastructural changes that contribute to such events remain unknown. Therefore, the effect of water deprivation for 24 hr, (as a model for dehydration) on the ultrastructure of mouse pial microvessels was investigated. The possible beneficial effect of garlic in preventing such ultrastructural changes was also investigated. Four groups of TO strain: control, control-garlic treated, dehydrated, and dehydrated-garlic treated male mice, 10/group, were used. Dehydration was induced by water deprivation for 24 hr. Garlic solution was i.p. injected at 0.1 ml/10g body weight. In urethane-anesthetized (2 mg/g, i.p.) mice, topical and transvessel bimodal fixation of pial microvessels was done with a phosphate buffered mixture of glutaraldehyde and paraformaldehyde, followed by a conventional electron microscopy procedure. Examination of control cerebral pial microvessels showed no evidence of cellular damage. Membranes of endothelial cells were intact. Within pial microvessels there was no evidence of platelet aggregation. Garlic treatments did not cause any ultrastructure abnormalities in control mice. Compared with control, dehydration caused the appearance of thrombi that consisted of platelet aggregates. Discoid platelets containing granules, spheroid degranulated platelets, and those with large pseudopodia were present in 80% of dehydrated mice. The venular endothelial surface of dehydrated mice revealed dilated profiles of endoplasmic reticulum and variously shaped vacuoles. Swelling of nuclear envelopes and mitochondrial distension were also present in dehydrated mice. Concomitant garlic treatment prevented most of these ultrastructural changes. These findings demonstrated the extent of damage to the pial microvessels in response to water deprivation and demonstrated the beneficial effect

  2. Characterisation of Growth and Ultrastructural Effects of the Xanthoria elegans Photobiont After 1.5 Years of Space Exposure on the International Space Station

    NASA Astrophysics Data System (ADS)

    Brandt, Annette; Posthoff, Eva; de Vera, Jean-Pierre; Onofri, Silvano; Ott, Sieglinde

    2016-06-01

    The lichen Xanthoria elegans has been exposed to space and simulated Mars-analogue environment in the Lichen and Fungi Experiment (LIFE) on the EXPOSE-E facility at the International Space Station (ISS). This long-term exposure of 559 days tested the ability of various organisms to cope with either low earth orbit (LEO) or Mars-analogue conditions, such as vacuum, Mars-analogue atmosphere, rapid temperature cycling, cosmic radiation of up to 215 ± 16 mGy, and insolation of accumulated doses up to 4.87 GJm-2, including up to 0.314 GJm-2 of UV irradiation. In a previous study, X. elegans demonstrated considerable resistance towards these conditions by means of photosynthetic activity as well as by post-exposure metabolic activity of 50-80 % in the algal and 60-90 % in the fungal symbiont (Brandt et al. Int J Astrobiol 14(3):411-425, 2015). The two objectives of the present study were complementary: First, to verify the high post-exposure viability by using a qualitative cultivation assay. Second, to characterise the cellular damages by transmission electron microscopy (TEM) which were caused by the space and Mars-analogue exposure conditions of LIFE. Since the algal symbiont of lichens is considered as the more susceptible partner (de Vera and Ott 2010), the analyses focused on the photobiont. The study demonstrated growth and proliferation of the isolated photobiont after all exposure conditions of LIFE. The ultrastructural analysis of the algal cells provided an insight to cellular damages caused by long-term exposure and highlighted that desiccation-induced breakdown of cellular integrity is more pronounced under the more severe space vacuum than under Mars-analogue atmospheric conditions. In conclusion, desiccation-induced damages were identified as a major threat to the photobiont of X. elegans. Nonetheless, a fraction of the photobiont cells remained cultivable after all exposure conditions tested in LIFE.

  3. Characterisation of Growth and Ultrastructural Effects of the Xanthoria elegans Photobiont After 1.5 Years of Space Exposure on the International Space Station.

    PubMed

    Brandt, Annette; Posthoff, Eva; de Vera, Jean-Pierre; Onofri, Silvano; Ott, Sieglinde

    2016-06-01

    The lichen Xanthoria elegans has been exposed to space and simulated Mars-analogue environment in the Lichen and Fungi Experiment (LIFE) on the EXPOSE-E facility at the International Space Station (ISS). This long-term exposure of 559 days tested the ability of various organisms to cope with either low earth orbit (LEO) or Mars-analogue conditions, such as vacuum, Mars-analogue atmosphere, rapid temperature cycling, cosmic radiation of up to 215 ± 16 mGy, and insolation of accumulated doses up to 4.87 GJm(-2), including up to 0.314 GJm(-2) of UV irradiation. In a previous study, X. elegans demonstrated considerable resistance towards these conditions by means of photosynthetic activity as well as by post-exposure metabolic activity of 50-80% in the algal and 60-90% in the fungal symbiont (Brandt et al. Int J Astrobiol 14(3):411-425, 2015). The two objectives of the present study were complementary: First, to verify the high post-exposure viability by using a qualitative cultivation assay. Second, to characterise the cellular damages by transmission electron microscopy (TEM) which were caused by the space and Mars-analogue exposure conditions of LIFE. Since the algal symbiont of lichens is considered as the more susceptible partner (de Vera and Ott 2010), the analyses focused on the photobiont. The study demonstrated growth and proliferation of the isolated photobiont after all exposure conditions of LIFE. The ultrastructural analysis of the algal cells provided an insight to cellular damages caused by long-term exposure and highlighted that desiccation-induced breakdown of cellular integrity is more pronounced under the more severe space vacuum than under Mars-analogue atmospheric conditions. In conclusion, desiccation-induced damages were identified as a major threat to the photobiont of X. elegans. Nonetheless, a fraction of the photobiont cells remained cultivable after all exposure conditions tested in LIFE.

  4. Zika Virus Induced Cellular Remodeling.

    PubMed

    Rossignol, Evan D; Peters, Kristen N; Connor, John H; Bullitt, Esther

    2017-03-20

    Zika virus (ZIKV) has been associated with morbidities such as Guillain-Barré, infant microcephaly, and ocular disease. The spread of this positive-sense, single-stranded RNA virus and its growing public health threat underscore gaps in our understanding of basic ZIKV virology. To advance knowledge of the virus replication cycle within mammalian cells, we use serial section three-dimensional electron tomography to demonstrate the widespread remodeling of intracellular membranes upon infection with ZIKV. We report extensive structural rearrangements of the endoplasmic reticulum and reveal stages of the ZIKV viral replication cycle. Structures associated with RNA genome replication and virus assembly are observed integrated within the endoplasmic reticulum, and we show viruses in transit through the Golgi apparatus for viral maturation, and subsequent cellular egress. This study characterizes in detail the three-dimensional ultrastructural organization of the ZIKV replication cycle stages. Our results show close adherence of the ZIKV replication cycle to the existing flavivirus replication paradigm.

  5. The dual specificity phosphatase Cdc25B, but not the closely related Cdc25C, is capable of inhibiting cellular proliferation in a manner dependent upon its catalytic activity.

    PubMed

    Varmeh-Ziaie, Shohreh; Manfredi, James J

    2007-08-24

    Cdc25B and Cdc25C are closely related dual specificity phosphatases that activate cyclin-dependent kinases by removal of inhibitory phosphorylations, thereby triggering entry into mitosis. Cdc25B, but not Cdc25C, has been implicated as an oncogene and been shown to be overexpressed in a variety of human tumors. Surprisingly, ectopic expression of Cdc25B, but not Cdc25C, inhibits cell proliferation in long term assays. Chimeric proteins generated from the two phosphatases show that the anti-proliferative activity is associated with the C-terminal end of Cdc25B. Indeed, the catalytic domain of Cdc25B is sufficient to suppress cell viability in a manner partially dependent upon its C-terminal 26 amino acids that is shown to influence substrate binding. Mutation analysis demonstrates that both the phosphatase activity of Cdc25B as well as its ability to interact with its substrates contribute to the inhibition of cell proliferation. These results demonstrate key differences in the biological activities of Cdc25B and Cdc25C caused by differential substrate affinity and recognition. This also argues that the antiproliferative activity of Cdc25B needs to be overcome for it to act as an oncogene during tumorigenesis.

  6. DNA damage associated with ultrastructural alterations in rat myocardium after loud noise exposure.

    PubMed Central

    Lenzi, Paola; Frenzilli, Giada; Gesi, Marco; Ferrucci, Michela; Lazzeri, Gloria; Fornai, Francesco; Nigro, Marco

    2003-01-01

    Noise exposure causes changes at different levels in human organs, particularly the cardiovascular system, where it is responsible for increasing heart rate, peripheral vascular resistance, and blood pressure. In this study, we evaluated the effect of noise exposure on DNA integrity and ultrastructure of rat cardiomyocytes. The exposure to loud noise (100 dBA) for 12 hr caused a significant increase of DNA damage, accompanied by swelling of mitochondrial membranes, dilution of the matrix, and cristolysis. These alterations were concomitant with increased in situ noradrenaline levels and utilization. Genetic and ultrastructural alterations did not decrease 24 hr after the cessation of the stimulus. An elevated oxyradical generation, possibly related to altered sympathetic innervation, is hypothesized as responsible for the induction and persistence of noise-induced cellular damage. PMID:12676600

  7. Ultrastructural analysis of adult mouse neocortex comparing aldehyde perfusion with cryo fixation

    PubMed Central

    Korogod, Natalya; Petersen, Carl CH; Knott, Graham W

    2015-01-01

    Analysis of brain ultrastructure using electron microscopy typically relies on chemical fixation. However, this is known to cause significant tissue distortion including a reduction in the extracellular space. Cryo fixation is thought to give a truer representation of biological structures, and here we use rapid, high-pressure freezing on adult mouse neocortex to quantify the extent to which these two fixation methods differ in terms of their preservation of the different cellular compartments, and the arrangement of membranes at the synapse and around blood vessels. As well as preserving a physiological extracellular space, cryo fixation reveals larger numbers of docked synaptic vesicles, a smaller glial volume, and a less intimate glial coverage of synapses and blood vessels compared to chemical fixation. The ultrastructure of mouse neocortex therefore differs significantly comparing cryo and chemical fixation conditions. DOI: http://dx.doi.org/10.7554/eLife.05793.001 PMID:26259873

  8. [Ultrastructure of the retina in flunitrazepam anesthesia].

    PubMed

    Antal, M

    1980-10-01

    Ultrastructure of the retina under experimental flunitrazepam anaesthesia of 1 hour duration was studied. Alterations of neurons and glial cells were not revealed neither after cessation of anaesthesia, nor following 24 or 48 hours after it. These findings seem to indicate that flunitrazepam has no effect on the metabolism of the retina, thus its application in the ophtalmology is free of side effects.

  9. Effects of camptothecin derivatives and topoisomerase dual inhibitors on Trypanosoma cruzi growth and ultrastructure

    PubMed Central

    2014-01-01

    Background Trypanosoma cruzi is the etiological agent of Chagas’ disease that is an endemic disease in Latin America and affects about 8 million people. This parasite belongs to the Trypanosomatidae family which contains a single mitochondrion with an enlarged region, named kinetoplast that harbors the mitochondrial DNA (kDNA). The kinetoplast and the nucleus present a great variety of essential enzymes involved in DNA replication and topology, including DNA topoisomerases. Such enzymes are considered to be promising molecular targets for cancer treatment and for antiparasitic chemotherapy. In this work, the proliferation and ultrastructure of T. cruzi epimastigotes were evaluated after treatment with eukaryotic topoisomerase I inhibitors, such as topotecan and irinotecan, as well as with dual inhibitors (compounds that block eukaryotic topoisomerase I and topoisomerase II activities), such as baicalein, luteolin and evodiamine. Previous studies have shown that such inhibitors were able to block the growth of tumor cells, however most of them have never been tested on trypanosomatids. Results Considering the effects of topoisomerase I inhibitors, our results showed that topotecan decreased cell proliferation and caused unpacking of nuclear heterochromatin, however none of these alterations were observed after treatment with irinotecan. The dual inhibitors baicalein and evodiamine decreased cell growth; however the nuclear and kinetoplast ultrastructures were not affected. Conclusions Taken together, our data showed that camptothecin is more efficient than its derivatives in decreasing T. cruzi proliferation. Furthermore, we conclude that drugs pertaining to a certain class of topoisomerase inhibitors may present different efficiencies as chemotherapeutical agents. PMID:24917086

  10. [Clinical significance of histopathologic and ultrastructural pathologic examination in etiological diagnosis of infantile cholestatic diseases].

    PubMed

    Zhao, Rui-qiu; Guan, Xiao-qin; Luo, Zi-guo; Xu, Hong-mei

    2010-09-01

    To study the features of histopathologic and ultrastructural pathologic changes of liver biopsy in patients with infantile cholestatic disease, and to investigate its diagnostic significance combining with the clinical data. Thirty-six children diagnosed as infantile cholestatic disease and received liver biopsy in Chongqing Medical University Children's Hospital from Jun 2007 to Oct 2008 were enrolled and the pathologic and ultrastructural pathologic changes of liver were analyzed. Morphologic changes under light microscope in liver tissues included hepatocyte swelling, hepatocyte denaturation, hepatocyte necrosis, multinucleated giant cell formation, bile duct proliferation, fiber tissues proliferation and inflammatory cells infiltration in liver lobules and portal regions. The characteristics of cholestasis including intralobular cholestasis, acinus formation, feather-like cytoplasmic filaments and bile stasis in bile canaliculi were observed. The morphologic changes of biliary atresia were observed in 7 cases whose image investigations showed no obstruction of biliary tract. Nuclear changes, resolution of cytoplasm, inflammatory cell infiltration, collagen fiber proliferation and increased number of lysosomes were observed under electromicroscope. Two cases of glycogen storage disease, 1 case of Niemann-Pick disease and 1 case of lipid storage disease with unknown cause were confirmed by the combination of histological changes and clinical manifestations. Common pathologic changes of liver tissues existed under light microscope or electroscope. The diagnosis of hereditary metabolic disorders could be made increasingly by application of these two technologies in clinical practice. It is difficult to diagnose biliary atresia in early childhood by image investigations and the pathological changes of liver tissues are helpful.

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

    PubMed Central

    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

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

    PubMed Central

    Succar, Lena; Boadle, Ross A; Harris, David C; Rangan, Gopala K

    2016-01-01

    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 junctions between podocytes is an early ultrastructural abnormality in CGN, preceding FPE and podocyte bridge formation and occurring in response to inflammatory injury. Podocyte-to-podocyte tight junction formation may be a compensatory mechanism to maintain the integrity of the glomerular filtration barrier following severe endocapillary injury. PMID:27920570

  13. Aerodynamics and pollen ultrastructure in Ephedra.

    PubMed

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

    2015-03-01

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

  14. Cellular mechanism through which parathyroid hormone-related protein induces proliferation in arterial smooth muscle cells: definition of an arterial smooth muscle PTHrP/p27kip1 pathway.

    PubMed

    Fiaschi-Taesch, Nathalie; Sicari, Brian M; Ubriani, Kiran; Bigatel, Todd; Takane, Karen K; Cozar-Castellano, Irene; Bisello, Alessandro; Law, Brian; Stewart, Andrew F

    2006-10-27

    Parathyroid hormone-related protein (PTHrP) is present in vascular smooth muscle (VSM), is markedly upregulated in response to arterial injury, is essential for normal VSM proliferation, and also markedly accentuates neointima formation following rat carotid angioplasty. PTHrP contains a nuclear localization signal (NLS) through which it enters the nucleus and leads to marked increases in retinoblastoma protein (pRb) phosphorylation and cell cycle progression. Our goal was to define key cell cycle molecules upstream of pRb that mediate cell cycle acceleration induced by PTHrP. The cyclin D/cdk-4,-6 system and its upstream regulators, the inhibitory kinases (INKs), are not appreciably influenced by PTHrP. In striking contrast, cyclin E/cdk-2 kinase activity is markedly increased by PTHrP, and this is a result of a specific, marked, PTHrP-induced proteasomal degradation of p27(kip1). Adenoviral restoration of p27(kip1) fully reverses PTHrP-induced cell cycle progression, indicating that PTHrP mediates its cell cycle acceleration in VSM via p27(kip1). In confirmation, adenoviral delivery of PTHrP to murine primary vascular smooth muscle cells (VSMCs) significantly decreases p27(kip1) expression and accelerates cell cycle progression. p27(kip1) is well known to be a central cell cycle regulatory molecule involved in both normal and pathological VSM proliferation and is a target of widely used drug-eluting stents. The current observations define a novel "PTHrP/p27(kip1) pathway" in the arterial wall and suggest that this pathway is important in normal arterial biology and a potential target for therapeutic manipulation of the arterial response to injury.

  15. Effect of low-power laser irradiation on protein synthesis and ultrastructure of human gingival fibroblasts.

    PubMed

    Marques, Márcia M; Pereira, Aymann N; Fujihara, Neusa A; Nogueira, Fernando N; Eduardo, Carlos P

    2004-01-01

    Low-power lasers improve wound healing. Cell proliferation and protein secretion are important steps of this process. The aim of this study was to analyze both protein synthesis and ultrastructural morphology of human gingival fibroblasts irradiated by a low-power laser. The cell line FMM1 was grown in nutritional deficit. Laser irradiation was carried out with a gallium-aluminum-arsenate (Ga-Al-As) diode laser (904 nm, 120 mW, energy density of 3 J/cm(2)). The protein synthesis analysis and ultrastructural morphology of control (non-irradiated) and irradiated cultures were obtained. There were changes in the structure of cytoplasm organelles of treated cells. The procollagen was not altered by the laser irradiation; however, there were a significant reduction of the amount of protein in the DMEM conditioned by irradiated cells. Low-power laser irradiation causes ultrastructural changes in cultured fibroblasts. We suggest that these alterations may lead to disturbances in the collagen metabolism. Copyright 2004 Wiley-Liss, Inc.

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

    PubMed

    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.

  17. Targeting genes in insulin-associated signalling pathway, DNA damage, cell proliferation and cell differentiation pathways by tocotrienol-rich fraction in preventing cellular senescence of human diploid fibroblasts.

    PubMed

    Durani, L W; Jaafar, F; Tan, J K; Tajul Arifin, K; Mohd Yusof, Y A; Wan Ngah, W Z; Makpol, S

    2015-01-01

    Tocotrienols have been known for their antioxidant properties besides their roles in cellular signalling, gene expression, immune response and apoptosis. This study aimed to determine the molecular mechanism of tocotrienol-rich fraction (TRF) in preventing cellular senescence of human diploid fibroblasts (HDFs) by targeting the genes in senescence-associated signalling pathways. Real time quantitative PCR (qRT-PCR) was utilized to evaluate the expression of genes involved in these pathways. Our findings showed that SOD1 and CCS-1 were significantly down-regulated in pre-senescent cells while CCS-1 and PRDX6 were up-regulated in senescent cells (p<0.05). Treatment with TRF significantly down-regulated SOD1 in pre-senescent and senescent HDFs, up-regulated SOD2 in senescent cells, CAT in young HDFs, GPX1 in young and pre-senescent HDFs, and CCS-1 in young, pre-senescent and senescent HDFs (p<0.05). TRF treatment also caused up-regulation of FOXO3A in all age groups of cells (p<0.05). The expression of TP53, PAK2 and CDKN2A was significantly increased in senescent HDFs and treatment with TRF significantly down-regulated TP53 in senescent cells (p<0.05). MAPK14 was significantly up-regulated (p<0.05) in senescent HDFs while no changes was observed on the expression of JUN. TRF treatment, however, down-regulated MAPK14 in young and senescent cells and up-regulated JUN in young and pre-senescent HDFs (p<0.05). TRF modulated the expression of genes involved in senescence-associated signalling pathways during replicative senescence of HDFs.

  18. The Effect of Spaceflight on the Ultrastructure of the Cerebellum

    NASA Technical Reports Server (NTRS)

    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

  19. Plantar fibromatosis: an immunohistochemical and ultrastructural study.

    PubMed

    de Palma, L; Santucci, A; Gigante, A; Di Giulio, A; Carloni, S

    1999-04-01

    The analogies between plantar fibromatosis and Dupuytren's disease (palmar fibromatosis) are well known. The latter is clinically more frequent and has been the object of extensive immunohistochemical and ultrastructural studies, with a view to investigating its pathogenesis. By contrast, such data on plantar fibromatosis are quite scarce. A histochemical, immunohistochemical, and ultrastructural study was performed on nodule tissue from six patients who were subjected to total fasciectomy for plantar fibromatosis. The study of myofibroblasts revealed features suggestive of their fibroblastic origin and evidenced a cytoskeleton and an extracellular filamentous system that could enable myofibroblasts to generate and exert the intracellular forces that contribute to the contraction of the aponeurosis. These aspects are similar to those observed in Dupuytren's disease and seem to lend support to the theory that the two diseases are expressions of the same disorder.

  20. Ciliary ultrastructure of polyplacophorans (Mollusca, Amphineura, Polyplacophora).

    PubMed

    Lundin, K; Schander, C

    2001-01-01

    This study is part of a series of papers aiming to investigate the phylogenetic significance of ciliary ultrastructure among molluscs and to test the hypothesis of a relationship between Xenoturbella and the molluscs. The ultrastructure of the ciliary apparatus on the gills of the polyplacophorans Leptochiton asellus and Tonicella rubra was studied. The gill cilia of the two species are similar in shape. The free part of the cilium is long with a slender distal part. There are two ciliary rootlets. One of them is short, broad and placed on the anterior face of the basal body. The other rootlet is conical and has a vertical orientation. Among the mollusca, two ciliary rootlets in the ciliary apparatus of multiciliate ectodermal cells have only been reported from the Chaetodermomorpha and Neomeniomorpha. This character state is likely plesiomorphic for the Mollusca and indicates a basal (nonderived) position of these taxa among the molluscs. No possible synapomorphic character with Xenoturbella bocki was found.

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

    PubMed Central

    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. PMID:26805432

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

    PubMed

    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.

  3. 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.

    PubMed

    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.

  4. Cytochemical characterization and ultrastructural organization in calluses of the agarophyte Gracilariopsis tenuifrons (Gracilariales, Rhodophyta).

    PubMed

    Bouzon, Zenilda Laurita; Schmidt, Eder Carlos; Almeida, Ana Carolina de; Yokoya, Nair S; Oliveira, Mariana Cabral de; Chow, Fungyi

    2011-01-01

    The culture and physiology of red macroalgae calluses are well documented. To date, however, no report has either performed a cytochemical analysis or characterized the ultrastructural organization of calluses at different stages of development and under the effect of plant growth regulators. Therefore, to undertake such analyses, this work studied the red seaweed Gracilariopsis tenuifrons (Bird et Oliveira) Fredericq et Hommersand. Morphology studies suggested three types of calluses: a) terminal callus having an irregular amorphous shape and filamentous projections originating from the cortical region of the thallus; b) apical callus growing on apical branches and having an elongated semispherical shape; and c) intercalary callus developing along the intermediary region of the thallus and having the appearance of small declivities with irregular edges. The abundance of intercalary calluses over terminal and apical calluses is most likely a result of a major cortical surface that would support the cellular growth required to generate calluses. Callus development was initially observed as a matrix of cellular disorganization with filamentous projections; then, the cellular mass seemed to become more compact with spherical uncolored aspect. The presence of starch grains in the inner part of the explant could be explained by absorption from the culture medium and by proper biosynthesis during callus development. Cell wall reaction to staining suggested cellulose and agar composition with acidic polysaccharides. Results suggest that none of the three morphological types of calluses showed any significant differences on the basis of either cytochemistry or ultrastructural organization.

  5. Ultrastructural differences between diabetic and idiopathic gastroparesis

    PubMed Central

    Faussone-Pellegrini, Maria Simonetta; Grover, Madhusudan; Pasricha, Pankaj J; Bernard, Cheryl E; Lurken, Matthew S; Smyrk, Thomas C; Parkman, Henry P; Abell, Thomas L; Snape, William J; Hasler, William L; Ünalp-Arida, Aynur; Nguyen, Linda; Koch, Kenneth L; Calles, Jorges; Lee, Linda; Tonascia, James; Hamilton, Frank A; Farrugia, Gianrico

    2012-01-01

    Abstract The ultrastructural changes in diabetic and idiopathic gastroparesis are not well studied and it is not known whether there are different defects in the two disorders. As part of the Gastroparesis Clinical Research Consortium, full thickness gastric body biopsies from 20 diabetic and 20 idiopathic gastroparetics were studied by light microscopy. Abnormalities were found in many (83%) but not all patients. Among the common defects were loss of interstitial cells of Cajal (ICC) and neural abnormalities. No distinguishing features were seen between diabetic and idiopathic gastroparesis. Our aim was to provide a detailed description of the ultrastructural abnormalities, compare findings between diabetic and idiopathic gastroparesis and determine if patients with apparently normal immunohistological features have ultrastructural abnormalities. Tissues from 40 gastroparetic patients and 24 age- and sex-matched controls were examined by transmission electron microscopy (TEM). Interstitial cells of Cajal showing changes suggestive of injury, large and empty nerve endings, presence of lipofuscin and lamellar bodies in the smooth muscle cells were found in all patients. However, the ultrastructural changes in ICC and nerves differed between diabetic and idiopathic gastroparesis and were more severe in idiopathic gastroparesis. A thickened basal lamina around smooth muscle cells and nerves was characteristic of diabetic gastroparesis whereas idiopathic gastroparetics had fibrosis, especially around the nerves. In conclusion, in all the patients TEM showed abnormalities in ICC, nerves and smooth muscle consistent with the delay in gastric emptying. The significant differences found between diabetic and idiopathic gastroparesis offers insight into pathophysiology as well as into potential targeted therapies. PMID:21914127

  6. Ultrastructural Correlates of Sulfur Mustard Toxicity

    DTIC Science & Technology

    1989-10-01

    number) FIELD GROUP SUBGROUP -)Sulfur mustard (HD), toxicity, lymphocytes in vitro, keratinocytes in culture, skin , ultrastructure, pathology. 19...sulfur mustard (HD) on 1) human lymphocytes in vitro, 2) human keratinocytes in culture, and 3) the skin of the hairless guiiea pig. While doses of...germinativum and the generation of microblisters at the dermal-epidermal junction were une ivocal to that reported for human- skin grafted to congenitally

  7. Observations on house fly larvae midgut ultrastructure after Brevibacillus laterosporus ingestion.

    PubMed

    Ruiu, Luca; Satta, Alberto; Floris, Ignazio

    2012-11-01

    The pathological and histopathological course caused by Brevibacillus laterosporus on house fly larvae has been investigated conducting observations on insect behavior and midgut ultrastructure. After dissection and fixation, gut tissues were analyzed under transmission electron microscopy (TEM) in order to compare in vivo-treated and non-treated (control) fly specimens. Treated larvae showed extensively reduced feeding and growth rate, then became sluggish and died within 72 h. A progressive midgut epithelium deterioration was observed in treated larvae, compared to the control. Ultrastructural changes consisted of microvilli disruption, cytoplasm vacuolization and general disorganization, endoplasmic reticulum deformation, mitochondria alteration. Deterioration became progressively more dramatic until the infected cells released their content into the gut lumen. Disruption was associated also with midgut muscular sheath and connective tissue. These ultrastructural changes are similar to those widely described for other entomopathogenic bacteria, such as Bacillus thuringiensis, against different insect species. The rapid disruption of cellular fine structure supports a hypothesis based on an interaction of toxins with the epithelial cell membranes reminiscent of the specific B. thuringiensis δ-endotoxins mechanism of action on other insect targets.

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

    PubMed

    Chemes, Hector E

    2013-01-01

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

  9. Effects of excess vitamin B6 intake on cerebral cortex neurons in rat: an ultrastructural study.

    PubMed

    Demir, Ramazan; Acar, Goksemin; Tanriover, Gamze; Seval, Yasemin; Kayisli, Umit Ali; Agar, Aysel

    2005-01-01

    The aim of this study was to investigate whether excess of vitamin B6 leads to ultrastructural changes in cerebral cortex of forty-eight healthy albino rats which were included in the study. Saline solution was injected to to the control groups (CG-10, n = 12 for 10 days; CG-15, n = 12 for 15 days; CG-20, n=12 for 20 days). The three experimental groups (EG-10, n = 12; EG-15, n = 12; EG-20, n = 12) were treated with 5 mg/kg vitamin B6 daily for 10 days (EG-10), 15 days (EG-15) and 20 days (EG-20). Brain tissues were prepared by glutaraldehyde-osmium tetroxide double fixation for ultrastructural analysis. No significant changes were observed in the control groups. The ultrastructural analysis revealed that the numbers of damaged mitochondria, lipofuscin granules and vacuoles were significantly higher in all the experimental groups than in the control groups (p < 0.05). However, synaptic density was significantly decreased in the experimental groups as compared to the control groups (p < 0.05). The results suggest that the excess of vitamin B6 intake causes damage to the cerebral cortex due to cellular intoxication and decreased synaptic density. Thus, careful attention should be paid to the time and dose of vitamin B6 recommended for patients who are supplemented with this vitamin.

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

    PubMed

    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.

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

    PubMed Central

    da Luz, João S. B.; de Oliveira, Erwelly B.; Martins, Monica C. B.; da Silva, Nicácio H.; Alves, Luiz C.; dos Santos, Fábio A. B.; da Silva, Luiz L. S.; Silva, Eliete C.; de Medeiros, Paloma L.

    2015-01-01

    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. PMID:25767824

  12. Clinical and ultrastructural spectrum of diffuse lung disease associated with surfactant protein C mutations.

    PubMed

    Peca, Donatella; Boldrini, Renata; Johannson, Jan; Shieh, Joseph T; Citti, Arianna; Petrini, Stefania; Salerno, Teresa; Cazzato, Salvatore; Testa, Raffaele; Messina, Francesco; Onofri, Alfredo; Cenacchi, Giovanna; Westermark, Per; Ullmann, Nicola; Ullman, Nicola; Cogo, Paola; Cutrera, Renato; Danhaive, Olivier

    2015-08-01

    Genetic defects of surfactant metabolism are associated with a broad range of clinical manifestations, from neonatal respiratory distress syndrome to adult interstitial lung disease. Early therapies may improve symptoms but diagnosis is often delayed owing to phenotype and genotype variability. Our objective was to characterize the cellular/ultrastructural correlates of surfactant protein C (SP-C) mutations in children with idiopathic diffuse lung diseases. We sequenced SFTPC - the gene encoding SP-C - SFTPB and ABCA3, and analyzed morphology, ultrastructure and SP expression in lung tissue when available. We identified eight subjects who were heterozygous for SP-C mutations. Median age at onset and clinical course were variable. None of the mutations were located in the mature peptide-encoding region, but were either in the pro-protein BRICHOS or linker C-terminal domains. Although lung morphology was similar to other genetic surfactant metabolism disorders, electron microscopy studies showed specific anomalies, suggesting surfactant homeostasis disruption, plus trafficking defects in the four subjects with linker domain mutation and protein misfolding in the single BRICHOS mutation carrier in whom material was available. Immunolabeling studies showed increased proSP-C staining in all cases. In two cases, amyloid deposits could be identified. Immunochemistry and ultrastructural studies may be useful for diagnostic purposes and for genotype interpretation.

  13. Ultrastructural characterization of macrophage-like mononuclear leukocytes in human astrocytic tumors.

    PubMed

    Arismendi-Morillo, Gabriel; Castellano-Ramírez, Alan; Medina, Zulamita

    2010-12-01

    The aim of this study was to describe the ultrastructural features of macrophage-like mononuclear leukocytes associated with human astrocytic tumors. Tumoral biopsies of 10 patients with a pathological diagnosis of astrocytic tumor by means of transmission electron microscopy were examined. The macrophage-like mononuclear leukocyte shows ultrastructural characteristics related with the physiologic phenotype of the alternatively activated macrophage (M2), localized principally around of tumoral vasculature and tumor milieu; classically activated macrophages (M1) in surrounding necrosis areas were observed. The presence of these two ultrastructural kinds of macrophage-like mononuclear leukocytes into different areas of the tumor denotes that cellular response of TAMs is dependent of microenvironment stimuli in different parts of a tumor. The process of transvascular emigration of monocyte/macrophage-like mononuclear leukocytes into tumor is presented. The preponderance of alternatively activated macrophage-like mononuclear leukocytes suggests disequilibrium between pro-tumoral leukocytes and anti-tumoral leukocytes. Therefore, macrophage polarization toward anti-tumoral macrophage-like mononuclear leukocytes would be a potential target for therapeutic manipulation in human astrocytic tumors.

  14. The ultrastructure of radiation injury in rat lung: modification by D-penicillamine. [/sup 60/Co

    SciTech Connect

    Port, C.D.; Ward, W.F.

    1982-10-01

    The present study compared the ultrastructure of radiation injury in the lungs of penicillamine-treated and untreated male rats sacrificed 3, 6, 9, or 12 months after a single exposure of 25 Gy of /sup 60/Co ..gamma..-rays to the right hemithorax. All morphological components of the irradiated lungs exhibited injury typical of pneumonitis progressing to interstitial fibrosis. In addition to these well-documented responses, several less common ultrastructural changes were noted, including capillary recanalization; focal disappearance of interstitial collagen fibers, initially perivascularly, then throughout some septa; and a low-grade but significant cellular reaction in the shielded left lung. Radiation reactions in the lungs of penicillamine-treated rats were qualitatively similar to those of untreated animals, but differed in the degree of change: collagen deposition was less extensive and less highly organized into fibers, capillary recanalization and disappearance of interstitial collagen were more common, and arterial wall thickening was reduced in the drug-treated rats. Thus the beneficial effect of penicillamine on the histopathology of irradiated rat lung does not appear to be attributable to unique ultrastructural phenomena. Rather, penicillamine treatment produces a generalized inhibition of pathologic events such as collagen accumulation and arterial wall thickening, and acceleration of restorative processes such as revascularization and collagen degradation.

  15. The Ultrastructural Changes of the Sertoli and Leydig Cells Following Streptozotocin Induced Diabetes

    PubMed Central

    Kianifard, Davoud; Sadrkhanlou, Rajab Ali; Hasanzadeh, Shapour

    2012-01-01

    Objective(s) This investigation was conducted to evaluate the effects of diabetes on the structure and function of testicular tissue. Materials and Methods Diabetes was induced in male adult rats by a single intraperitoneal injection of streptozotocin. Body and testicular weight, hormonal analyses, histological and ultrastructural analyses were measured. Results The body and testicular weights were dropped significantly (P< 0.05) in diabetic rats in comparison with control rats. On the other hand, in diabetic rats, the blood glucose level increased significantly (P< 0.05). The blood plasma levels of testosterone, 17-β estradiol, progesterone, FSH and LH were reduced in diabetic rats. Histomorphological studies were revealed reduction in diameter of seminiferous tubules and germinal epithelium height, edema in interstitial tissue, germ cell depletion, decrease in cellular population and activity with disruption of spermatogenesis in diabetic rats. Ultrastructural study showed the mitochondrial change and reduction of smooth endoplasmic reticulum in Sertoli and presence of lipid droplets in Leydig cells of diabetic rat’s testes. Conclusion The results of the present study confirmed that, the ultrastructural changes of Sertoli and Leydig cells, brought about by streptozotocin induced diabetes, because of the alterations in pituitary gonadotropins, and these changes influence the normal spermatogenesis in rats. PMID:23493249

  16. Pulsed electromagnetic wave exposure induces ultrastructural damage and upregulated expression of heat shock protein 70 in the rat adenohypophysis.

    PubMed

    Cheng, Kang; Ren, Dong-Qing; Yi, Jun; Zhou, Xiao-Guang; Yang, Wen-Qing; Chen, Yong-Bin; Li, Yong-Qiang; Huang, Xiao-Feng; Zeng, Gui-Ying

    2015-08-01

    The aim of the present study was to investigate the ultrastructural damage and the expression of heat shock protein 70 (HSP70) in the rat adenohypophysis following pulsed electromagnetic wave (PEMW) exposure. The rats were randomly divided into four groups: Sham PEMW exposure, 1 x 10(4) pulses of PEMW exposure, 1 x 10(5) pulses of PEMW exposure and 3 x 10(5) pulses of PEMW exposure. Whole body radiation of 1 x 10(4) pulses, 1 x 10(5) pulses and 3 x 10(5) pulses of PEMW were delivered with a field strength of 100 kV/m. The rats in each group (n=6 in each) were sacrificed 12, 24, 48 and 96 h after PEMW exposure. Transmission electron microscopy was then used to detect the ultrastructural changes and immunocytochemistry was used to examine the expression of HSP70. Cellular damage, including mitochondrial vacuolation occurred as early as 12 h after PEMW exposure.More severe cellular damages, including cell degeneration and necrosis, occurred 24 and 48 h after PEMW exposure. The PEMW-induced cellular damage increased as the number of PEMW pulses increased. In addition, the expression of HSP70 significantly increased following PEMW exposure and peaked after 12 h. These findings suggested that PEMW induced ultrastructural damages in the rat adenohypophysis and that HSP70 may have contributed to the PEMW-induced adenohypophyseal damage.

  17. [Senescence and cellular immortality].

    PubMed

    Trentesaux, C; Riou, J-F

    2010-11-01

    Senescence was originally described from the observation of the limited ability of normal cells to grow in culture, and may be generated by telomere erosion, accumulation of DNA damages, oxidative stress and modulation of oncogenes or tumor suppressor genes. Senescence corresponds to a cellular response aiming to control tumor progression by limiting cell proliferation and thus constitutes an anticancer barrier. Senescence is observed in pre-malignant tumor stages and disappears from malignant tumors. Agents used in standard chemotherapy also have the potential to induce senescence, which may partly explain their therapeutic activities. It is possible to restore senescence in tumors using targeted therapies that triggers telomere dysfunction or reactivates suppressor genes functions, which are essential for the onset of senescence.

  18. Ultrastructure of in vitro Matured Human Oocytes.

    PubMed

    Shahedi, Abbas; Khalili, Mohammad Ali; Soleimani, Mehrdad; Morshedizad, Shekoufeh

    2013-12-01

    Approximately 20% of recovered oocytes are immature and discarded in intracytoplasmic sperm injection (ICSI) procedures. These oocytes represent a potential resource for both clinical and basic science application. The aim of this study was to evaluate the ultrastructure architecture of in vitro matured human oocytes using transmission electron microscopy (TEM). A total of 204 immature oocytes from infertile patients who underwent ICSI cycles were included in this prospective study. Immature oocytes were divided into two groups: (i) GV oocytes (n = 101); and (ii) MI oocytes (n = 103). Supernumerary fresh in vivo matured oocytes (n = 10) were used as control. The rates of maturations were 61.38% for GV and 73.78% for MI oocytes in IVM medium (P = 0.07). However, the rate of oocyte arrest was significant between groups (P <0 .05). Ultrastructurally; in vitro and in vivo matured oocytes appeared round, with a homogeneous cytoplasm, an intact oolemma and an intact zona pellucida. However, immature oocytes indicated numerous large mitochondria-vesicle complexes (M-VC). Ultrastructural changes of M-VC in IVM groups emphasize the need for further research in order to refine culture conditions and improve the implantation rate of in-vitro matured oocytes.

  19. Nematodes ultrastructure: complex systems and processes.

    PubMed

    Basyoni, Maha M A; Rizk, Enas M A

    2016-12-01

    Nematode worms are among the most ubiquitous organisms on earth. They include free-living forms as well as parasites of plants, insects, humans and other animals. Recently, there has been an explosion of interest in nematode biology, including the area of nematode ultrastructure. Nematodes are round with a body cavity. They have one way guts with a mouth at one end and an anus at the other. They have a pseudocoelom that is lined on one side with mesoderm and on the other side with endoderm. It appears that the cuticle is a very complex and evolutionarily plastic feature with important functions involving protection, body movement and maintaining shape. They only have longitudinal muscles so; they seem to thrash back and forth. While nematodes have digestive, reproductive, nervous and excretory systems, they do not have discrete circulatory or respiratory systems. Nematodes use chemosensory and mechanosensory neurons embedded in the cuticle to orient and respond to a wide range of environmental stimuli. Adults are made up of roughly 1000 somatic cells and hundreds of those cells are typically associated with the reproductive systems. Nematodes ultrastructure seeks to provide studies which enable their use as models for diverse biological processes including; human diseases, immunity, host-parasitic interactions and the expression of phylogenomics. The latter has, however, not been brought into a single inclusive entity. Consequently, in the current review we tried to provide a comprehensive approach to the current knowledge available for nematodes ultrastructures.

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

    PubMed

    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.

  1. Ultrastructure of medial rectus muscles in patients with intermittent exotropia

    PubMed Central

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

    2016-01-01

    Purpose To study the ultrastructure of the medial rectus in patients with intermittent exotropia at different ages. Patients and methods The medial recti were harvested surgically from 20 patients with intermittent exotropia. Patients were divided into adolescent (age<18 years, n=10) and adult groups (age >18 years, n=10). The normal control group included five patients without strabismus and undergoing eye enucleation. Hematoxylin and eosin staining and transmission electron microscopy were used to visualize the medial recti. Western blot was used to determine the levels of myosin and actin. Results Varying fiber thickness, atrophy, and misalignment of the medial recti were visualized under optical microscope in patients with exotropia. Electron microscopy revealed sarcomere destruction, myofilament disintegration, unclear dark and light bands, collagen proliferation, and fibrosis. The adolescent group manifested significantly higher levels of myosin and actin than the adult group (P<0.05). Conclusion Younger patients with intermittent exotropia show stronger contraction of the medial recti compared with older patients. Our findings suggest that childhood was the appropriate time for surgery as the benefit of the intervention was better than in adulthood. PMID:26514242

  2. Dexamethasone induced ultrastructural changes in cultured human trabecular meshwork cells.

    PubMed

    Wilson, K; McCartney, M D; Miggans, S T; Clark, A F

    1993-09-01

    Glucocorticoid-induced ocular hypertension has been demonstrated in both animals and humans. It is possible that glucocorticoid-induced changes in trabecular meshwork (TM) cells are responsible for this hypertension. In order to elaborate further the effect of glucocorticoids on the trabecular meshwork, the ultrastructural consequences of dexamethasone (DEX) treatment were examined in three different human TM cell lines. Confluent TM cells were treated with 0.1 microM of DEX for 14 days, and then processed for light, epifluorescent microscopy or transmission electron microscopy (TEM). The effect of DEX treatment on TM cell and nuclear size was quantified using computer assisted morphometrics. Morphometric analysis showed a significant increase in both TM cell and nuclear size after 14 days of DEX treatment. Epifluorescent microscopy of rhodamine-phalloidin stained, control TM cells showed the normal arrangement of stress fibers. In contrast, DEX-treated TM cells showed unusual geodesic dome-like cross-linked actin networks. Control TM cells had the normal complement and arrangement of organelles as well as electron dense inclusions and large vacuoles. DEX-treated TM cells showed stacked arrangements of smooth and rough endoplasmic reticulum, proliferation of the Golgi apparatus, pleomorphic nuclei and increased amounts of extracellular matrix material. The DEX-induced alterations observed in the present study may be an indication of the processes that are occurring in the in vivo disease process.

  3. Ultrastructural findings in lymph nodes from pigs suffering from naturally occurring postweaning multisystemic wasting syndrome.

    PubMed

    Rodriguez-Cariño, C; Segalés, J

    2009-07-01

    The aims of this study were to evaluate ultrastructural lesions in lymph nodes from postweaning multisystemic wasting syndrome (PMWS)-affected pigs and to correlate these alterations with detection of viral-like particles (VLPs). Samples of lymph nodes were taken from 4 PMWS-affected pigs and 2 healthy animals and processed by transmission electron microscopy. Significant ultrastructural alterations were only noted in PMWS-affected pigs, mainly in histiocytes and rarely in other cell types. Histiocytes showed severe swelling and proliferation of mitochondria, and proliferation and dilation of rough endoplasmic reticulum and Golgi complex. Infected histiocytes contained large numbers of intracytoplasmic inclusion (ICI) bodies with VLPs; some histiocytes also had intranuclear inclusions (INIs). Small inclusions were surrounded by double membrane, with a granular appearance or containing paracrystalline arrays; icosahedral VLPs were 8-17 nm in diameter. Large ICIs were double-membrane bounded or not and contained VLPs usually forming paracrystalline arrays. ICIs were often found next to mitochondria with severe swelling, and also inside them. INIs were not surrounded by membranes and contained virions of 10-13 nm diameter. Lymphocyte depletion was a striking finding of lymph nodes from PMWS-affected pigs. The inclusion bodies containing VLPs referred to in the present study should be classified as viral factories, suggesting that viral replication is probably a frequent event in macrophages, in which mitochondria might play a role.

  4. Three-Dimensional Reconstruction, by TEM Tomography, of the Ultrastructural Modifications Occurring in Cucumis sativus L. Mitochondria under Fe Deficiency

    PubMed Central

    Vigani, Gianpiero; Faoro, Franco; Ferretti, Anna Maria; Cantele, Francesca; Maffi, Dario; Marelli, Marcello; Maver, Mauro; Murgia, Irene; Zocchi, Graziano

    2015-01-01

    Background Mitochondria, as recently suggested, might be involved in iron sensing and signalling pathways in plant cells. For a better understanding of the role of these organelles in mediating the Fe deficiency responses in plant cells, it is crucial to provide a full overview of their modifications occurring under Fe-limited conditions. The aim of this work is to characterize the ultrastructural as well as the biochemical changes occurring in leaf mitochondria of cucumber (Cucumis sativus L.) plants grown under Fe deficiency. Methodology/Results Mitochondrial ultrastructure was investigated by transmission electron microscopy (TEM) and electron tomography techniques, which allowed a three-dimensional (3D) reconstruction of cellular structures. These analyses reveal that mitochondria isolated from cucumber leaves appear in the cristae junction model conformation and that Fe deficiency strongly alters both the number and the volume of cristae. The ultrastructural changes observed in mitochondria isolated from Fe-deficient leaves reflect a metabolic status characterized by a respiratory chain operating at a lower rate (orthodox-like conformation) with respect to mitochondria from control leaves. Conclusions To our knowledge, this is the first report showing a 3D reconstruction of plant mitochondria. Furthermore, these results suggest that a detailed characterization of the link between changes in the ultrastructure and functionality of mitochondria during different nutritional conditions, can provide a successful approach to understand the role of these organelles in the plant response to Fe deficiency. PMID:26107946

  5. Three-Dimensional Reconstruction, by TEM Tomography, of the Ultrastructural Modifications Occurring in Cucumis sativus L. Mitochondria under Fe Deficiency.

    PubMed

    Vigani, Gianpiero; Faoro, Franco; Ferretti, Anna Maria; Cantele, Francesca; Maffi, Dario; Marelli, Marcello; Maver, Mauro; Murgia, Irene; Zocchi, Graziano

    2015-01-01

    Mitochondria, as recently suggested, might be involved in iron sensing and signalling pathways in plant cells. For a better understanding of the role of these organelles in mediating the Fe deficiency responses in plant cells, it is crucial to provide a full overview of their modifications occurring under Fe-limited conditions. The aim of this work is to characterize the ultrastructural as well as the biochemical changes occurring in leaf mitochondria of cucumber (Cucumis sativus L.) plants grown under Fe deficiency. Mitochondrial ultrastructure was investigated by transmission electron microscopy (TEM) and electron tomography techniques, which allowed a three-dimensional (3D) reconstruction of cellular structures. These analyses reveal that mitochondria isolated from cucumber leaves appear in the cristae junction model conformation and that Fe deficiency strongly alters both the number and the volume of cristae. The ultrastructural changes observed in mitochondria isolated from Fe-deficient leaves reflect a metabolic status characterized by a respiratory chain operating at a lower rate (orthodox-like conformation) with respect to mitochondria from control leaves. To our knowledge, this is the first report showing a 3D reconstruction of plant mitochondria. Furthermore, these results suggest that a detailed characterization of the link between changes in the ultrastructure and functionality of mitochondria during different nutritional conditions, can provide a successful approach to understand the role of these organelles in the plant response to Fe deficiency.

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

    PubMed

    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.

  7. Hyperbaric oxygenation alters carotid body ultrastructure and function.

    PubMed

    Torbati, D; Sherpa, A K; Lahiri, S; Mokashi, A; Albertine, K H; DiGiulio, C

    1993-05-01

    We previously demonstrated that chronic normobaric hyperoxia (NH) for 60-67 h attenuated the carotid chemosensory response to hypoxia, probably initiated by the generation of reactive oxygen species (ROS). Since biological systems are affected by oxygen in a dose-dependent manner, we hypothesized that hyperbaric oxygenation (HBO) would affect the cellular mechanisms of oxygen chemoreception in a shorter time. To test the hypothesis, we studied the effects of oxygen at 5 atmospheres absolute (ATA) on cats (n = 7) carotid body ultrastructure and chemosensory responses to hypoxia, hypercapnia, and to bolus injections of cyanide, nicotine and dopamine. Four control cats breathed room air at 1 ATA. At the termination of the experiments, carotid bodies from 4 cats in each group were fixed and prepared for electron microscopy and morphometry. On the average, HBO diminished the chemosensory responsiveness to hypoxia (P < 0.01, unpaired t-test) within about 2 h, supporting the hypothesis. The responses to hypercapnia or bolus injections of cyanide, nicotine and dopamine were normal. HBO did not diminish the distribution of the dense-cored vesicles but significantly increased the mean volume-density of mitochondria and decreased the cristated area per mitochondrion in the glomus cells. The latter suggests a link between oxidative metabolism and chemosensing, and the former excludes availability of neurotransmitters being the cause of the blunted chemosensory response to hypoxia.

  8. Ultrastructure of Mycobacterium marinum granuloma in striped bass Morone saxatilis

    USGS Publications Warehouse

    Gauthier, David T.; Vogelbein, W.K.; Ottinger, C.A.

    2004-01-01

    An emerging epizootic of mycobacteriosis currently threatens striped bass Morone saxatilis populations in Chesapeake Bay, USA. Several species of mycobacteria, including Mycobacterium marinum, species resembling M. avium, M. gordonae, M. peregrinum, M. scrofulaceum and M. terrae, and the new species M. shottsii have been isolated from diseased and healthy bass. In this study, we describe the ultrastructure of developing M. marinum granulomas in experimentally infected bass over a period of 45 wk. The primary host response to injected mycobacteria was formation of large macrophage aggregations containing phagocytosed bacilli, M. marinum were always contained within phagosomes. Close association of lysosomes with mycobacterial phagosomes, as well as the presence of electron-opaque material within phagosomes, suggested phagolysosomal fusion. Development of granulomas involved epithelioid transformation of macrophages, followed by appearance of central necrosis. Desmosomes were present between mature epithelioid cells. The necrotic core region of M. marinum granulomas was separated from overlying epithelioid cells by several layers of flattened, electron-opaque spindle-shaped cells. These cells appeared to be formed by compression of epithelioid cells and, aside from a flattened nucleus, did not possess recognizable organelles. Following the development of well-defined, paucibacillary granulomas, secondary disease was observed. Recrudescence was marked by bacterial replication followed by disruption of granuloma architecture, including loss of epithelioid and spindle cell layers. In advanced recrudescent lesions, normal tissue was replaced by macrophages, fibroblasts, and other inflammatory leukocytes. Large numbers of mycobacteria were observed, both intracellular and suspended in cellular debris.

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

    PubMed

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

    2015-11-01

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

  10. SIRT1 inhibits the mouse intestinal motility and epithelial proliferation

    USDA-ARS?s Scientific Manuscript database

    SIRT1 inhibits the mouse intestinal motility and epithelial proliferation. Sirtuin 1 (SIRT1), a NAD+-dependent histone deacetylase, is involved in a wide array of cellular processes, including glucose homeostasis, energy metabolism, proliferation and apoptosis, and immune response. However, it is un...

  11. Highlights on ultrastructural pathology of human sperm.

    PubMed

    Joshi, Narahari V; Cruz, Ibis; Osuna, Jesus A

    2011-01-01

    Applications of atomic force microscopy to ultrastructural investigation of human spermatozoa are -discussed, with particular emphasis to their most common pathological alterations, which are recognized to be associated with male infertility. Morphological alterations can be located in the head, neck piece, and/or in the flagellum. The consequences of these defects on infertility-related topics are examined in the light of aberrations caused in varicocele and in other spermatozoa morphological alterations like globozoospermia, oligoasthenospermia, and in semen from patients with HIV syndrome. Special attention is given to the temperature effects on sperm abnormalities. The application of the present approach to pharmacology, namely, the development of male contraceptive methods, is also referred.

  12. Ultrastructure of cyst differentiation in parasitic protozoa.

    PubMed

    Chávez-Munguía, Bibiana; Omaña-Molina, Maritza; González-Lázaro, Mónica; González-Robles, Arturo; Cedillo-Rivera, Roberto; Bonilla, Patricia; Martínez-Palomo, Adolfo

    2007-05-01

    Cysts represent a phase in the life cycle of biphasic parasitic protozoa that allow them to survive under adverse environmental conditions. Two events are required for the morphological differentiation from trophozoite to cyst and from cyst to trophozoite: the encystation and excystation processes. In this paper, we present a review of the ultrastructure of the encystation and excystation processes in Entamoeba invadens, Acanthamoeba castellanii, and Giardia lamblia. The comparative electron microscopical observations of these events here reported provide a morphological background to better understand recent advances in the biochemistry and molecular biology of the differentiation phenomena in these microorganisms.

  13. Ultrastructural findings in natural canine hepatozoonosis.

    PubMed

    Hervás, J; Carrasco, L; Sierra, M A; Méndez, A; Gómez-Villamandos, J C

    1997-04-01

    The ultrastructure of several stages of Hepatozoon canis found in dogs with clinically and histologically diagnosed infections was determined using transmission electron microscopy. Merozoites, macro- and microschizonts and gamonts were found in spleen, liver, kidneys and lungs. Macro- and micromeronts were characterized by their size and by the presence of intracytoplasmic amylopectin granules. Gamonts, which provide the basis for clinical diagnosis of the disease, were observed within mononuclear cells (monocytes/macrophages); they were butterfly-shaped and exhibited varying electron densities. On the basis of the microscopic observations reported here, it is clear that the life cycle of H. canis is a complex one.

  14. Ultrastructure of eccrine cystadenoma. A case report.

    PubMed

    Hassan, M O; Khan, M A

    1979-10-01

    A case of eccrine cystadenoma was studied by electron microscopy. The tumor showed two types of cells, luminal and basal cells. The cells lacked the characteristics of the secretory segment of the sweat glands. The features of the luminal cells are similar to those of the intradermal portion of the eccrine sweat duct. In some areas, the lesion showed features characteristic of apocrine gland structure. Nuclear bodies were very frequent. The ultrastructural findings of eccrine cystadenoma support an origin from the ductal portion of eccrine sweat glands.

  15. Ultrastructural detection of kinetochores by silver impregnation.

    PubMed

    Rufas, J S; Mazzella, C; García de la Vega, C; Suja, J A

    1994-09-01

    We describe a simple silver impregnation method for the ultrastructural detection of kinetochores on meiotic chromosomes of the grasshopper Eyprepocnemis plorans. Testes were fixed with glutaraldehyde and silver-impregnated. After Epon 812 embedding, ultrathin cutting and counterstaining with uranyl acetate, sections were studied by transmission electron microscopy. The meiotic chromosomes showed differentially silver-impregnated 'ball and cup' kinetochores. Some pericentriolar material also showed silver deposits. These observations are discussed in the light of previous results obtained by light microscopy of silver-stained spermatocytes in which both kinetochores and pericentriolar material were also preferentially stained. These results suggest a role for acidic proteins in the composition of these structures.

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

    PubMed

    Shapiro, Adam J; Leigh, Margaret W

    2017-09-15

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

  17. The Spectrum of Mitochondrial Ultrastructural Defects in Mitochondrial Myopathy

    PubMed Central

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

    2016-01-01

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

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

    NASA Astrophysics Data System (ADS)

    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

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

    PubMed Central

    Al-Adawi, Kawther; Al-Nabhani, Abdurahman; Al-Kindi, Mohamed

    2017-01-01

    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. PMID:28377926

  20. Ultrastructural findings in human spinal pia mater in relation to subarachnoid anesthesia.

    PubMed

    Reina, Miguel Angel; De León Casasola, Oscar De León; Villanueva, M C; López, Andrés; Machés, Fabiola; De Andrés, José Antonio

    2004-05-01

    We examined ultrastructural details such as the cellular component and membrane thickness of human spinal pia mater with the aim of determining whether fenestrations are present. We hypothesized that pia mater is not a continuous membrane but, instead, that there are fenestrations across the pial cellular membrane. The lumbar dural sac from 7 fresh human cadavers was removed, and samples from lumbar spinal pia mater were studied by special staining techniques, immunohistochemistry, and transmission and scanning electron microscopy. A pial layer made by flat overlapping cells and subpial tissue was identified. We found fenestrations in samples from human spinal pia mater at the thoracic-lumbar junction, conus medullaris, and nerve root levels, but these fenestrations did not appear at the thoracic level. We speculate whether the presence of fenestrations in human spinal pia mater at the level of the lumbar spinal cord and at the nerve root levels has any influence on the transfer of local anesthetics across this membrane. The ultrastructural anatomy of the human pia mater, such as pial cells, membrane thickness, and subpial tissue at different levels of the thoracic and lumbar spinal cord and nerve roots, was studied by special staining techniques, immunohistochemistry, and transmission and scanning electron microscopy. Fenestrations were found in samples at the thoracic-lumbar junction, conus medullaris, and nerve root levels. No fenestrations were found in samples at the thoracic level. At present, we cannot determine the significance of these findings.

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

    NASA Astrophysics Data System (ADS)

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

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

  2. Ultrastructural changes in cerebral capillary pericytes in aged Notch3 mutant transgenic mice.

    PubMed

    Gu, Xin; Liu, Xiao-Yun; Fagan, Austin; Gonzalez-Toledo, Maria E; Zhao, Li-Ru

    2012-02-01

    Pericytes, the specialized vascular smooth muscle cells (VSMCs), play an important role in supporting and maintaining the structure of capillaries. Pericytes show biochemical and physiologic features similar to VSMC, usually containing smooth muscle actin fibers and rich endoplasm reticulum. Studies have indicated that degeneration of VSMCs due to Notch3 mutations is the cause of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). However, it remains unclear whether the Notch3 mutation also affects cerebral cortex capillary pericytes. In this ultrastructural morphologic study, the authors have observed pathological changes in the cerebral cortex capillary pericytes in aged mice that carry human mutant Notch3 genes. The number of abnormal pericytes in the cerebral cortex in Notch3 gene mutant mice was slightly increased when compared to an age-matched control group. Morphologically, the pericytes in the brains of Notch3 gene mutant mice showed more severe cellular injury, such as the presence of damaged mitochondria, secondary lysosomes, and large cytoplasmic vesicles. In addition, morphologic structures related to autophagy were also present in the pericytes of Notch3 gene mutant group. These ultrastructural morphologic alterations suggest that Notch3 mutation precipitates age-related pericytic degeneration that might result in cellular injury and trigger autophagic apoptosis. Microvascular dysfunction due to pericyte degeneration could initiate secondary neurodegenerative changes in brain parenchyma. These findings provide new insight into understanding the role of pericyte degeneration in the phathogenesis of CADASIL disease.

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

    PubMed

    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.

  4. Ultrastructural studies on dengue virus type 2 infection of cultured human monocytes.

    PubMed

    Mosquera, Jesus A; Hernandez, Juan Pablo; Valero, Nereida; Espina, Luz Marina; Añez, German J

    2005-03-31

    Early interaction of dengue virus and monocyte/macrophages could be an important feature for virus dissemination after its initial entry via the mosquito vector. Since ultrastructural analysis of this interaction has not been reported, dengue type 2 (DEN2) virus-infected human monocyte cultures were studied at 1, 2, 4 and 6 hours after infection. Typical dengue particles and fuzzy coated viral particles were 35 to 42 nm and 74 to 85 nm respectively. Viruses were engulfed by phagocytosis and macropicnocytosis leading to huge vacuoles and phagosomes inside the monocytes. Interaction of monocytes with DEN2 virus induced apoptosis, characterized by nuclear condensation and fragmentation, cellular shrinkage, blebbing and budding phenomena and phagocytosis of apoptotic cells by neighboring monocytes. This finding was confirmed by TUNEL. Ultrastructural features associated to DEN2 virus replication were not observed. These data suggest that clearance of the virus by monocytes and cellular death are the main features during the initial interaction of DEN2 virus and monocytes and this could be important in the rapid elimination of the virus after infection by mosquito vector.

  5. Ultrastructural studies on dengue virus type 2 infection of cultured human monocytes

    PubMed Central

    Mosquera, Jesus A; Hernandez, Juan Pablo; Valero, Nereida; Espina, Luz Marina; Añez, German J

    2005-01-01

    Background Early interaction of dengue virus and monocyte/macrophages could be an important feature for virus dissemination after its initial entry via the mosquito vector. Since ultrastructural analysis of this interaction has not been reported, dengue type 2 (DEN2) virus-infected human monocyte cultures were studied at 1, 2, 4 and 6 hours after infection. Results Typical dengue particles and fuzzy coated viral particles were 35 to 42 nm and 74 to 85 nm respectively. Viruses were engulfed by phagocytosis and macropicnocytosis leading to huge vacuoles and phagosomes inside the monocytes. Interaction of monocytes with DEN2 virus induced apoptosis, characterized by nuclear condensation and fragmentation, cellular shrinkage, blebbing and budding phenomena and phagocytosis of apoptotic cells by neighboring monocytes. This finding was confirmed by TUNEL. Ultrastructural features associated to DEN2 virus replication were not observed. Conclusion These data suggest that clearance of the virus by monocytes and cellular death are the main features during the initial interaction of DEN2 virus and monocytes and this could be important in the rapid elimination of the virus after infection by mosquito vector. PMID:15801983

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

    PubMed

    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.

  7. A recombined fusion protein PTD-Grb2-SH2 inhibits the proliferation of breast cancer cells in vitro.

    PubMed

    Yin, Jikai; Cai, Zhongliang; Zhang, Li; Zhang, Jian; He, Xianli; Du, Xilin; Wang, Qing; Lu, Jianguo

    2013-03-01

    The growth factor receptor bound protein 2 (Grb2) is one of the affirmative targets for cancer therapy, especially for breast cancer. In this study, we hypothesized the Src-homology 2 (SH2) domain in Grb2 may serve as a competitive protein-binding agent to interfere with the proliferation of breast cancer cells in vitro. We designed, constructed, expressed and purified a novel fusion protein containing the protein transduction domain (PTD) and Grb2-SH2 domain (we named it after PTD-Grb2-SH2). An immunofluorescence assay was used to investigate the location of PTD-Grb2-SH2 in cells. MTT assay and EdU experiments were applied to detect the proliferation of breast cancer cells. The ultra-structure was observed using transmission electron microscopy. Flow cytometry was used to determine the cytotoxicity of PTD-Grb2-SH2 on cell proliferation. We successfully obtained the PTD-Grb2-SH2 fusion protein in soluble form using a prokaryotic expression system. The new fusion protein successfully passed through both the cellular and nuclear membranes of breast cancer cells. The MTT assay showed that PTD-Grb2-SH2 exhibited significant toxicity to breast cancer cells in a dose- and time-dependent manner in vitro. EdU identified the decreased proliferation rates in treated MDA-MB-231 and SK-BR-3 cells. Observation by transmission electron microscopy and flow cytometry further confirmed the cytotoxicity as apoptosis. Our results show that the HIV1-TAT domain is a useful tool for transporting a low molecular weight protein across the cell membrane in vitro. The PTD-Grb2-SH2 may be a novel agent for breast cancer therapy.

  8. Ultrastructure of Cosmarium strains (Zygnematophyceae, Streptophyta) collected from various geographic locations shows species-specific differences both at optimal and stress temperatures.

    PubMed

    Stamenković, Marija; Woelken, Elke; Hanelt, Dieter

    2014-11-01

    Plant species collected from various climatic zones and stressed in vitro at various temperatures reveal changes in cellular ultrastructure which are in accordance with the climate at their sampling sites. This observation initiated the investigation to establish if stress at different temperatures may cause diverse extents of changes in the ultrastructure of microalgal strains originating from different geographic zones. The study revealed that the six Cosmarium strains demonstrated ultrastructural characteristics that were consistent with their source location under optimal, low and high temperature conditions, pointing to their preference to specific climatic niches. Interestingly, chloroplasts of all of the Cosmarium strains correspond to a sun-adapted type, which is concomitant with earlier statements that these strains are rendered as high-light adapted algae. The Cosmarium strains developed multiple ultrastructural responses which enabled them to cope with excessive temperatures, occasionally occurring in desmid natural habitats. The appearance of cubic membranes and increased number of plastoglobules may represent the first line in protection against high-temperature stress, which is accompanied by the alteration of protein synthesis and the appearance of stress granules in order to preserve cell homeostasis. However, the prolonged warm- or cold-temperature stress obviously initiated the programmed cell death, as concluded from the appearance of several ultrastructural features observed in all of the Cosmarium strains. The fair acclimation possibilities and the ability to undergo programmed cell death in order to save the population, certainly favor the cosmopolitan distribution of the genus Cosmarium.

  9. Nuclear Proliferation Challenges

    SciTech Connect

    Professor William Potter

    2005-11-28

    William C. Potter, Director of the Center for Non Proliferation Studies and the Center for Russian and Eurasian Studies at the Monterey Institute of International Studies, will present nuclear proliferation challenges following the 2005 Nuclear Non-Proliferation Treaty (NPT) Review Conference. In addition to elucidating reasons for, and implications of, the conference’s failure, Dr. Potter will discuss common ground between nuclear proliferation and terrorism issues and whether corrective action can be taken.

  10. Ultrastructure, biology, and phylogenetic relationships of kinorhyncha.

    PubMed

    Neuhaus, Birger; Higgins, Robert P

    2002-07-01

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

  11. Cytological and ultrastructural studies on root tissues

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

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

  12. Cytological and ultrastructural studies on root tissues

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

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

  13. How methylglyoxal kills bacteria: An ultrastructural study.

    PubMed

    Rabie, Erika; Serem, June Cheptoo; Oberholzer, Hester Magdalena; Gaspar, Anabella Regina Marques; Bester, Megan Jean

    2016-01-01

    Antibacterial activity of honey is due to the presence of methylglyoxal (MGO), H2O2, bee defensin as well as polyphenols. High MGO levels in manuka honey are the main source of antibacterial activity. Manuka honey has been reported to reduce the swarming and swimming motility of Pseudomonas aeruginosa due to de-flagellation. Due to the complexity of honey it is unknown if this effect is directly due to MGO. In this ultrastructural investigation the effects of MGO on the morphology of bacteria and specifically the structure of fimbriae and flagella were investigated. MGO effectively inhibited Gram positive (Bacillus subtilis; MIC 0.8 mM and Staphylococcus aureus; MIC 1.2 mM) and Gram negative (P. aeruginosa; MIC 1.0 mM and Escherichia coli; MIC 1.2 mM) bacteria growth. The ultrastructural effects of 0.5, 1.0 and 2 mM MGO on B. substilis and E. coli morphology was then evaluated. At 0.5 mM MGO, bacteria structure was unaltered. For both bacteria at 1 mM MGO fewer fimbriae were present and the flagella were less or absent. Identified structures appeared stunted and fragile. At 2 mM MGO fimbriae and flagella were absent while the bacteria were rounded with shrinkage and loss of membrane integrity. Antibacterial MGO causes alterations in the structure of bacterial fimbriae and flagella which would limit bacteria adherence and motility.

  14. Ultrastructure of quiescent oocytes of Cebus albifrons.

    PubMed Central

    Barton, B R; Hertig, A T

    1975-01-01

    Quiescent oocytes of the monkey Cebus albifrons were examined with the electron microscope. In many respects the ultrastructure of these cells was similar to that of other mammalian species. Elongate and oval mitochondria, lamellar Golgi complexes, small profiles of smooth endoplasmic reticulum, and vacuolar organelles were randomly distributed around a round nucleus which usually contained a nucleolus and clumps of heterochromatin. Among the unusual morphological characteristics of these oocytes are 'membranous aggregates', membrane-bound organelles containing a complex of convoluted membranes, some very dense rod-like structures and a droplet of moderate density which resembles lipid. A similar droplet is frequently found in mitochondria. Rough endoplasmic reticulum is abundant in many of these oocytes, forming parallel arrays and concentric rings around the nucleus. Folded membrane complexes, apparent elaborations of smooth endoplasmic reticulum, are frequently found in the cytoplasm in continuity with cisternae of smooth and rough endoplasmic reticulum and associated with vesicles which often contain flocculent material. The morphology of Cebus oocytes suggests a greater rate of steroid and protein synthesis, transport, and storage than is usually indicated by the ultrastructure of other mammalian oocytes. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 PMID:811634

  15. Ultrastructure of quiescent oocytes of Cebus albifrons.

    PubMed

    Barton, B R; Hertig, A T

    1975-11-01

    Quiescent oocytes of the monkey Cebus albifrons were examined with the electron microscope. In many respects the ultrastructure of these cells was similar to that of other mammalian species. Elongate and oval mitochondria, lamellar Golgi complexes, small profiles of smooth endoplasmic reticulum, and vacuolar organelles were randomly distributed around a round nucleus which usually contained a nucleolus and clumps of heterochromatin. Among the unusual morphological characteristics of these oocytes are 'membranous aggregates', membrane-bound organelles containing a complex of convoluted membranes, some very dense rod-like structures and a droplet of moderate density which resembles lipid. A similar droplet is frequently found in mitochondria. Rough endoplasmic reticulum is abundant in many of these oocytes, forming parallel arrays and concentric rings around the nucleus. Folded membrane complexes, apparent elaborations of smooth endoplasmic reticulum, are frequently found in the cytoplasm in continuity with cisternae of smooth and rough endoplasmic reticulum and associated with vesicles which often contain flocculent material. The morphology of Cebus oocytes suggests a greater rate of steroid and protein synthesis, transport, and storage than is usually indicated by the ultrastructure of other mammalian oocytes.

  16. Ultrastructural Morphology of Sperm from Human Globozoospermia.

    PubMed

    Ricci, Giuseppe; Andolfi, Laura; Zabucchi, Giuliano; Luppi, Stefania; Boscolo, Rita; Martinelli, Monica; Zweyer, Marina; Trevisan, Elisa

    2015-01-01

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

  17. Ultrastructural Morphology of Sperm from Human Globozoospermia

    PubMed Central

    Ricci, Giuseppe; Andolfi, Laura; Zabucchi, Giuliano; Luppi, Stefania; Boscolo, Rita; Martinelli, Monica; Zweyer, Marina; Trevisan, Elisa

    2015-01-01

    Globozoospermia is a rare disorder characterized by the presence of sperm with round head, lacking acrosome. Coiling tail around the nucleus has been reported since early human studies, but no specific significance has conferred it. By contrast, studies on animal models suggest that coiling tail around the nucleus could represent a crucial step of defective spermatogenesis, resulting in round-headed sperm. No observations, so far, support the transfer of this hypothesis to human globozoospermia. The purpose of this work was to compare ultrastructural morphology of human and mouse model globozoospermic sperm. Sperm have been investigated by using scanning and transmission electron microscopy. The images that we obtained show significant similarities to those described in GOPC knockout mice, an animal model of globozoospermia. By using this model as reference, we were able to identify the probable steps of the tail coiling process in human globozoospermia. Although we have no evidence that there is the same pathophysiology in man and knocked-out mouse, the similarities between these ultrastructural observations in human and those in the experimental model are very suggestive. This is the first demonstration of the existence of relevant morphological homologies between the tail coiling in animal model and human globozoospermia. PMID:26436098

  18. Spermatogenesis and sperm ultrastructure in the polychaete genus Ophryotrocha (Dorvilleidae)

    NASA Astrophysics Data System (ADS)

    Pfannenstiel, Hans-Dieter; Grünig, Charlotte

    1990-06-01

    The details of spermatogenesis and spermiogenesis are described for Ophryotrocha puerilis. The ultrastructure of mature sperm is shown for O. puerilis, O. hartmanni, O. gracilis, O. diadema, O. labronica, and O. notoglandulata. Clusters of sixteen cells each are proliferated by two stem cells in each setigerous segment of O. puerilis representing the very early stages of both oogenesis and spermatogenesis. In each spermatocyte-I cluster, the cells are interconnected by cytoplasmic bridges. Early, clusters are enveloped by peritoneal sheath cells. These transient gonad walls break down prior to meiosis. The meiotic processes may start in the clusters with the cells still interconnected, or during breakdown of the original cluster, giving rise to smaller subclusters of both spermatocytes I and spermatocytes II with various numbers of cells. Finally, spermatid tetrads are present. As spermiogenesis progresses, the tetrads disintegrate. Golgi vesicles in both spermatocytes and spermatids contain electron-dense material, presumably preacrosomal. The acrosome is formed by such vesicles. In the six species studied here, the acrosomes appear to be of a similar overall structure but are of different shape. Centrioles are usually located beneath the acrosome. The distal centriole forms the basal body of a flagellum-like cytoplasmic process. The microtubules of these flagellar equivalents do not show a normal ciliar arrangement. The flagellar equivalent appears to be non-motile. In O. hartmanni and in O. notoglandulata, a flagellar equivalent is missing. Microtubules originating from the proximal end of the distal centriole stretch to the nuclear envelope. This feature appears to be especially conspicuous in O. puerilis and in O. labronica. In O. labronica and in O. notoglandulata, bundles of microtubules paralleling the cell perimeter appear to stabilise the sperm. Various numbers of mitochondria are either randomly distributed around the nucleus or accumulate on one side

  19. [Stimulation of proliferation by carnosine: cellular and transcriptome approaches].

    PubMed

    Vishniakova, Kh S; Babizhaev, M A; Aliper, A M; Buzdin, A A; Kudriavtseva, A V; Egorov, E E

    2014-01-01

    Concentration of endogenous dipeptide carnosine in human muscle tissue reaches tens of millimoles. For more than 100 years of research, a lot of data concerning carnosine functions were accumulated, among which anti-aging effects are regarded most important. Heire, effect of carnosine in cell cultures was studied. It has been found that apart from the known action--an increase of the Hayflick limit and morphological rejuvenation--carnosine stimulates cell division in colony-forming assays and in the course of transition of cells to the quiescent state. The analysis of the transcriptome showed that carnosine-induced changes are mainly related to positive regulation of the cell cycle at all levels, from the onset of the DNA synthesis to chromosome condensation. One can suppose that the revealed stimulation of the cell cycle account for the carnosine-induced rejuvenation processes and a high concentration ofcarnosine in muscle tissue is required for the muscle recovery (regeneration) after excess loads.

  20. [Influence of polysaccharide from Aloe vera on the proliferation of the human epithelial cells cultured in vitro].

    PubMed

    Chen, Xiao-dong; Wu, Bo-yu; Jiang, Qiong; Wang, Shun-bin; Huang, Li-ying; Wang, Zhong-cheng

    2005-12-01

    To investigate the influence of polysaccharide from Aloe Vera (AP) on the proliferation of the human epithelial cells cultured in vitro. The human epithelial cells undergoing 3 to 4 passages of confluence culture were randomly divided into control and 25, 50, 100, 200 and 400 mg/L AP groups according to different dosage of the polysaccharide (AP) added into the culture medium. In the control group (C), equal volume of DK-SFM medium was added to the culturing cells. The conjugation time of epithelial cells, the changes in the cell morphology and ultrastructure were observed under inverted phase contrast microscope and transmission electron microscope, respectively. The cell proliferation was measured by MTT, cell count analysis and [(3)H]-TdR incorporation. Flow cytometry analysis was employed to detect the cell cycle. The leakage rate of lactate dehydrogenase (LDH) was assayed for the evaluation of the epithelial cell injury. There was no significant difference in the morphology of the epithelial cells among the groups under inverted phase contrast microscope. But under the transmission electron microscope (TEM), the cells in 100 to 400 mg/L AP groups were seen to have proliferated actively, with euchromatin dominant in the nuclei, while heterochromatin was dominant in the cellular nucleus in control and 25 mg/L AP groups. The confluence time of epithelial cells in 50, 100, 200, 400 mg/L AP groups (154 +/- 12, 141 +/- 20, 130 +/- 19, 124 +/- 13) h preceded noticeably than that in control group (182 +/- 8) h, (P < 0.01). The cell proliferation in 100, 200, 400 mg/L groups reached the peak on the 5th day after AP treatment, while that in control and other groups was delayed by 1 to 2 days. The survival rate of the cells in 25 to 400 mg/L AP groups increased dramatically compared with that in control group, with its [(3)H]-TdR incorporation levels significantly increased in a dose dependent manner. The leakage rate of LDH in 200 and 400 mg/L AP groups was lower than

  1. Ultrastructure and phylogeny of Ustilago coicis *

    PubMed Central

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

    2013-01-01

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

  2. Ultrastructure and properties of Paecilomyces lilacinus spores.

    PubMed

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

    2002-10-01

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

  3. The effect of age on mitochondrial ultrastructure.

    PubMed

    Wilson, P D; Franks, L M

    1975-01-01

    The ultrastructure of perfused livers and of mitochondrial fractions from 6-month-old and 30-month-old C57/BL mice were studied. In old mice the liver cell mitochondria were enlarged and rounded with a light 'foamy', vacuolated matrix, short cristae and a loss of dense granules. Quantitative studies showed a 60% increase in the mean size and an increased proportion of larger mitochondria in intact 30-month-old perfused livers. Endothelial and Kupffer cell mitochondria were smaller than those of the parenchymal cells. Mitochondria in pellets prepared from 6- and 30-month-old livers were rounded and condensed, although there were a few larger and 'foamy' mitochondria in the preparations from old mice. Up to 47% of large mitochondria in the old livers were lost during cell fractionation.

  4. Ultrastructural immunochemistry of J chains in chickens.

    PubMed

    Moriya, O; Ichikawa, Y

    1990-01-01

    Using ultrastructural immunochemistry, we have determined subcellular localization of J chain molecules in chicken splenic cells. The majority of J chain positive cells (JPC) were lymphoblast-like cells. The data show that J chains predominantly are localized in cytoplasm with a considerable amount distributed on the cell surface. In the cytoplasm, J chains were diffusely expressed. Furthermore, these J chain molecules were clearly seen as cluster type. In addition to the J chain localization of subcellular organelles as described above, J chains were partly found on perinuclear spaces. As J chains are key protein in B cell differentiation into immunoglobulin (Ig) producing cells, these findings might help for studying regulation of B cell differentiation in addition to revealing the molecular assembly of polymeric Ig.

  5. Control of morphogenesis in Geodermatophilus: ultrastructural studies.

    PubMed

    Ishiguro, E E; Wolfe, R S

    1970-10-01

    Geodermatophilus grows in two major forms, a nonmotile irregularly shaped aggregate of coccoid cells (C-form) and a motile budding rod (R-form). Morphogenesis can be controlled by an unidentified factor in Tryptose which is required for maintenance of the organism in the C-form and for differentiation of the R-form to the C-form. Morphogenetic events occur synchronously in the described system. Ultrastructural studies show that the major difference between C- and R-forms is in cells envelope structure. R-form cell walls consist of two layers, an inner transparent membranous layer (10 to 12.5 nm thick) and an outer dense diffuse layer (7.5 to 10 nm). In addition to these layers, the C-form has a thick fibrous layer (30 nm) over the dense layer. This layer appears to be a cementing substance which holds the coccoid cells together.

  6. Control of Morphogenesis in Geodermatophilus: Ultrastructural Studies

    PubMed Central

    Ishiguro, Edward E.; Wolfe, R. S.

    1970-01-01

    Geodermatophilus grows in two major forms, a nonmotile irregularly shaped aggregate of coccoid cells (C-form) and a motile budding rod (R-form). Morphogenesis can be controlled by an unidentified factor in Tryptose which is required for maintenance of the organism in the C-form and for differentiation of the R-form to the C-form. Morphogenetic events occur synchronously in the described system. Ultrastructural studies show that the major difference between C- and R-forms is in cells envelope structure. R-form cell walls consist of two layers, an inner transparent membranous layer (10 to 12.5 nm thick) and an outer dense diffuse layer (7.5 to 10 nm). In addition to these layers, the C-form has a thick fibrous layer (30 nm) over the dense layer. This layer appears to be a cementing substance which holds the coccoid cells together. Images PMID:5473909

  7. The mammalian tubuli recti: ultrastructural study.

    PubMed

    Osman, D I; Plöen, L

    1978-09-01

    The ultrastructure of the tubuli recti was studied in the testes of sexually mature bulls, boars, rams, goats, rabbits and rats fixed by vascular perfusion. The tubuli recti are lined with a simple epithelium that varies in height, from squamous to tall columnar according to the species and the region. The cells are characterized by extensive lateral and tortuous basal plasma membranes and a luminal border with microvilli. Tight junctions and desmosomes are found in the upper half of the lateral borders. The Golgi apparatus is sizable and associated with it are coated vesicles and many smooth vesicles concentrated towards the luminal border. A distal segment of the tubuli recti is found in bulls only and is characterized by a high epithelium which is thrown into folds giving the lumen a festooned appearance. It is suggested that the epithelial cells of the tubuli recti are involved in fluid exchange and in the removal of unwanted spermatozoa.

  8. Effects of ultrasound upon endothelial cell ultrastructure

    NASA Astrophysics Data System (ADS)

    Rodemer, Claus; Jenne, Jürgen; Fatar, Marc; Hennerici, Michael G.; Meairs, Stephen

    2012-11-01

    A number of new brain applications for therapeutic ultrasound are emerging including drug delivery through BBB opening, enhancement of angiogenesis, sonothrombolysis and neuromodulation. Safety remains important as alterations in the cytoskeleton and tight junctions of endothelial cells have been described. In this study we characterize the in vitro effects of ultrasound on cell morphology using a new human brain cell line (hCMEC/D3). Changes in ultrastructure were analyzed with antibodies against tubulin, actin and catenin. Transport was analyzed by measuring transferrin uptake. No significant changes were seen after continuous wave ultrasound treatment of hCMEC/D3 cells grown in Opticell{trade mark, serif} chambers. We could not observe disassembled actin stress fibers or variations in the microtubule network. However, severe damage occurred in cells cultured in petri dishes.

  9. Ultrastructure of developing ascospores in Sordaria brevicollis.

    PubMed

    Hackett, C J; Chen, K C

    1976-05-01

    The ultrastructure of ascospore wall formation in the pyrenomycete Sordaria brevicollis was studied in developing asci at progressive time intervals. From early spore delimitation through final stage of maturation, the wall of the ascospore differentiated into four composite layers, the periascosporium the delineation ascosporium, the subascosproium, and the endoascosproium, While ascospores were at the hyaline stage of development,they possessed only the periascosporium and delineation ascosporium as their wall components. At about 7 to 8 days from the initiation of the cross, the spores developed a yellow color, and this coloration was always associated with the elaboration of the subascorsporium just internal to the ascosporium. Asthe spores continued to progressively darken in color, the subascosporium was seen to increase in complexity, electron density, and thickness. Soon after the formation of the subascosporium, the endoascosporium began to develop de novo and was, therefore, the last wall layer formed as the spore approached maturity.

  10. Ultrastructure of developing ascospores in Sordaria brevicollis.

    PubMed Central

    Hackett, C J; Chen, K C

    1976-01-01

    The ultrastructure of ascospore wall formation in the pyrenomycete Sordaria brevicollis was studied in developing asci at progressive time intervals. From early spore delimitation through final stage of maturation, the wall of the ascospore differentiated into four composite layers, the periascosporium the delineation ascosporium, the subascosproium, and the endoascosproium, While ascospores were at the hyaline stage of development,they possessed only the periascosporium and delineation ascosporium as their wall components. At about 7 to 8 days from the initiation of the cross, the spores developed a yellow color, and this coloration was always associated with the elaboration of the subascorsporium just internal to the ascosporium. Asthe spores continued to progressively darken in color, the subascosporium was seen to increase in complexity, electron density, and thickness. Soon after the formation of the subascosporium, the endoascosporium began to develop de novo and was, therefore, the last wall layer formed as the spore approached maturity. Images PMID:1262318

  11. Metabolic and Ultrastructural Changes in Winter Wheat during Ice Encasement Under Field Conditions 1

    PubMed Central

    Pomeroy, M. Keith; Andrews, Christopher J.

    1978-01-01

    The effect of ice encasement on the physiological, metabolic, and ultrastructural properties of winter wheat (Triticum aestivum L.) grown under field conditions was examined by artificially encasing winter wheat in ice during early winter. Cold hardiness and survival of ice-encased seedlings declined less rapidly in Kharkov, a cold-hardy cultivar than in Fredrick, a less hardy cultivar. Ethanol did not accumulate in non-iced seedlings, but increased rapidly upon application of an ice sheet. Lactic acid accumulated in both cultivars during late autumn, prior to ice encasement, and elevated levels of lactic acid were maintained throughout the winter in seedlings from both iced and non-iced plots. The rate of O2 consumption of shoot tissue of seedlings from non-iced plots remained relatively constant throughout the winter, but declined rapidly in seedlings from ice encased plots. Major ultrastructural changes did not occur in shoot apex cells of non-iced winter wheat seedlings during cold hardening under field conditions. However, the imposition of an ice cover in early January resulted in a proliferation of the endoplasmic reticulum membrane system of the cells, frequently resulting in the formation of concentric whorls of membranes, often enclosing cytoplasmic organelles. Electrondense areas within the cytoplasm which appeared to be associated with the expanded endoplasmic reticulum were also frequently observed. ImagesFIG. 3FIG. 4FIG. 5FIG. 6FIG. 7FIG. 8 PMID:16660390

  12. Ultrastructural and molecular changes in the developing small intestine of the toad Bufo regularis.

    PubMed

    Sakr, S A; Badawy, G M; El-Borm, H T

    2014-01-01

    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.

  13. Metabolic and Ultrastructural Changes Associated with Flooding at Low Temperature in Winter Wheat and Barley 1

    PubMed Central

    Pomeroy, M. Keith; Andrews, Christopher J.

    1979-01-01

    Cold-hardened winter wheat (Triticum aestivum L. cv. Fredrick) and winter barley (Hordeum vulgare L. cv. Dover) were exposed to total flooding at 2 C. Dover seedlings were damaged more quickly than Fredrick, and after 3 weeks of flooding the survival of Dover was reduced to 10% and Fredrick to about 50%. Tissue moisture was slightly greater in Dover than Fredrick throughout the 4-week flooding period. Carbon dioxide and ethanol accumulated throughout the 4-week flooding period in both cultivars. Lactic acid increased rapidly during the 1st week of flooding, and remained relatively constant during the remainder of the flooding period. Oxygen consumption of seedling shoot tissue after exposure to flooding declined abruptly after only 1 day of flooding, but recovered somewhat during the subsequent 2 weeks. The effect of flooding was more pronounced on the ultrastructure of Dover than Fredrick. Although proliferation of endoplasmic reticulum was observed in the early stages of flooding in both cultivars, the occurrence of distinct parallel arrays and concentric whorls of membranes was prevalent in the flooded barley. Severe ultrastructural damage to a large proportion of apical cells in both cultivars was observed after 2 to 3 weeks of flooding. Images PMID:16661023

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

    PubMed Central

    Sakr, S. A.; Badawy, G. M.; El-Borm, H. T.

    2014-01-01

    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. PMID:24715821

  15. Ultrastructure of spore development in Scutellospora heterogama.

    PubMed

    Jeffries, Peter; Robinson-Boyer, Louisa; Rice, Paul; Newsam, Ray J; Dodd, John C

    2007-07-01

    The ultrastructural detail of spore development in Scutellospora heterogama is described. Although the main ontogenetic events are similar to those described from light microscopy, the complexity of wall layering is greater when examined at an ultrastructural level. The basic concept of a rigid spore wall enclosing two inner, flexible walls still holds true, but there are additional zones within these three walls distinguishable using electron microscopy, including an inner layer that is involved in the formation of the germination shield. The spore wall has three layers rather than the two reported previously. An outer, thin ornamented layer and an inner, thicker layer are both derived from the hyphal wall and present at all stages of development. These layers differentiate into the outer spore layer visible at the light microscope level. A third inner layer unique to the spore develops during spore swelling and rapidly expands before contracting back to form the second wall layer visible by light microscopy. The two inner flexible walls also are more complex than light microscopy suggests. The close association with the inner flexible walls with germination shield formation consolidates the preferred use of the term 'germinal walls' for these structures. A thin electron-dense layer separates the two germinal walls and is the region in which the germination shield forms. The inner germinal wall develops at least two sub-layers, one of which has an appearance similar to that of the expanding layer of the outer spore wall. An electron-dense layer is formed on the inner surface of the inner germinal wall as the germination shield develops, and this forms the wall surrounding the germination shield as well as the germination tube. At maturity, the outer germinal wall develops a thin, striate layer within its substructure.

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

    SciTech Connect

    Han, Yu; Zhong, Cuiping; Hong, Liu; Wang, Ye; Qiao, Li; Qiu, Jianhua

    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.

  17. Ultrastructural features of the early secretory pathway in Trichoderma reesei.

    PubMed

    Nykänen, Marko; Birch, Debra; Peterson, Robyn; Yu, Hong; Kautto, Liisa; Gryshyna, Anna; Te'o, Junior; Nevalainen, Helena

    2016-05-01

    We have systematically analysed the ultrastructure of the early secretory pathway in the Trichoderma reesei hyphae in the wild-type QM6a, cellulase-overexpressing Rut-C30 strain and a Rut-C30 transformant BV47 overexpressing a recombinant BiP1-VenusYFP fusion protein with an endoplasmic reticulum (ER) retention signal. The hyphae were studied after 24 h of growth using transmission electron microscopy, confocal microscopy and quantitative stereological techniques. All three strains exhibited different spatial organisation of the ER at 24 h in both a cellulase-inducing medium and a minimal medium containing glycerol as a carbon source (non-cellulase-inducing medium). The wild-type displayed a number of ER subdomains including parallel tubular/cisternal ER, ER whorls, ER-isolation membrane complexes with abundant autophagy vacuoles and dense bodies. Rut-C30 and its transformant BV47 overexpressing the BiP1-VenusYFP fusion protein also contained parallel tubular/cisternal ER, but no ER whorls; also, there were very few autophagy vacuoles and an increasing amount of punctate bodies where particularly the recombinant BiP1-VenusYFP fusion protein was localised. The early presence of distinct strain-specific features such as the dominance of ER whorls in the wild type and tub/cis ER in Rut-C30 suggests that these are inherent traits and not solely a result of cellular response mechanisms by the high secreting mutant to protein overload.

  18. Inflammatory reaction in experimental hepatic amebiasis. An ultrastructural study.

    PubMed Central

    Tsutsumi, V.; Martinez-Palomo, A.

    1988-01-01

    One of the hallmarks of tissue necrosis produced by the human protozoan parasite Entamoeba histolytica, the causative agent of human amebiasis, appeared to be the lack of inflammatory reaction to the invading trophozoites. Recent evidence suggests, however, that inflammatory cells do appear during early stages of amebic destructive lesions and that they contribute to the establishment of foci of tissue necrosis in intestinal and liver lesions. The present analysis of the fine-structural changes that take place during early stages of amebic liver abscesses induced in hamsters after the intraportal inoculation of axenic amebas has shown that large numbers of polymorphonuclear leukocytes (PMNs) are recruited around invading amebas. These leukocytes lyse as a consequence of contact-mediated damage induced by the trophozoites. Amebas were also capable of ingesting apparently intact PMNs. Macrophages and eosinophils were also recruited at the foci of inflammation. At all times examined, trophozoites of Entamoeba histolytica survived in spite of being in close contact with PMNs or degranulating eosinophils. The ultrastructural observations have also shown the lack of direct contact between amebas and liver parenchymal cells during the initial stages of the focal liver necrosis induced by the parasite, therefore supporting the view that hepatic damage may be effected indirectly through lysis of inflammatory cells. The results also provide a basis for the understanding of the induction of experimental protective immunity against invasive amebiasis, a process which seems to be mostly dependent on cellular mechanisms. Images Figure 1 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 PMID:3337207

  19. Fat body of the frog Rana esculenta: an ultrastructural study.

    PubMed

    Zancanaro, C; Merigo, F; Digito, M; Pelosi, G

    1996-03-01

    In the frog, the fat body is the largest body lipid deposit and is associated with the gonad. The aim of the present work was to investigate the fine structure of the fat body at different periods of the annual cycle and during prolonged starvation. Results indicate that fat body cells of Rana esculenta caught in autumn and after winter hibernation resemble mammalian adipocytes of white adipose tissue and contain markers of adipose tissue, such as S-100 protein and lipoproteinlipase. However, unlike mammalian adipocytes, fat body adipocytes consistently show small lipid droplets associated with their single, large lipid deposits, a lack of a definite external lamina, and the presence of cellular prolongations and spicula at their surfaces. Transmission and scanning electron microscopy in association with lanthanum tracer experiments suggest that in fat body adipocytes a vesicular-tubular system connects the cytoplasm and the interstitial space. In June (i.e., during the reproductive period), fat body adipocytes appear to have lost much of their lipid deposit and adjacent adipocytes show interdigitation of their plasma membranes and prominent Golgi complexes. In starved frogs, fat body cells can be almost devoid of lipid and in regression to a near-mesenchymal state. Nevertheless, these fat bodies still contain lipoproteinlipase activity (approximately 45% of that found in lipid-filled ones), indicating persistent adipose differentiation of the cells therein. Results presented here show that the R. esculenta fat body is an adipose organ undergoing reversible extreme changes in adipocyte fat content, which are associated with definite ultrastructural features. The fat body represents a suitable model for studying adipose tissue under different and extreme physiological conditions.

  20. Alteration in ultrastructural morphology of bovine embryos following subzonal microinjection of bovine viral diarrhea virus (BVDV).

    PubMed

    Kubovicová, E; Makarevich, A V; Pivko, J; Chrenek, P; Grafenau, P; Ríha, L'; Sirotkin, A V; Louda, F

    2008-08-01

    The aim of the present study was to evaluate the development and ultrastructure of preimplantation bovine embryos that were exposed to bovine viral diarrhea virus (BVDV) in vitro. The embryos were recovered from superovulated and fertilized Holstein-Friesian donor cows on day 6 of the estrous cycle. Compact morulae were microinjected with 20 pl of BVDV suspension (10(5.16) TCID(50)/ml viral stock diluted 1:4) under the zona pellucida (ZP), then washed in SOF medium and cultured for 24-48 h. Embryos were evaluated for developmental stages and then processed immunocytochemically for the presence of viral particles, using fluorescent anti-BVDV-FITC conjugate. Ultrastructure of cellular organelles was analysed by transmission electron microscopy (TEM).After microinjection of BVDV under the ZP, significantly more (p<0.001) embryos (83.33%) were arrested at the morula stage compared with the intact control (30.33%). Immunocytochemical analysis localized the BVDV-FITC signal inside the microinjected embryos. TEM revealed: (i) the presence of virus-like particles in the dilated endoplasmic reticulum and in cytoplasmic vacuoles of the trophoblast and embryoblast cells; (ii) the loss of microarchitecture: and (iii) abnormal disintegrated nuclei, which lacked reticular structure and the heterochromatin area. In all, the embryo nuclear structure was altered and the microarchitecture of the nucleolus had disappeared when compared with the nuclei from control embryos. Dilatation of the intercellular space and the loss of the intercellular gap junctions were often observed in bovine BVDV-exposed embryos. These findings provide evidence for the adverse effect of BVDV virus on the development of bovine embryos, which is related to irreversible changes in the ultrastructure of cell organelles.

  1. Effect of low temperature on growth and ultra-structure of Staphylococcus spp.

    PubMed

    Onyango, Laura A; Dunstan, R Hugh; Gottfries, Johan; von Eiff, Christof; Roberts, Timothy K

    2012-01-01

    The effect of temperature fluctuation is an important factor in bacterial growth especially for pathogens such as the staphylococci that have to remain viable during potentially harsh and prolonged transfer conditions between hosts. The aim of this study was to investigate the response of S. aureus, S. epidermidis, and S. lugdunensis when exposed to low temperature (4°C) for prolonged periods, and how this factor affected their subsequent growth, colony morphology, cellular ultra-structure, and amino acid composition in the non-cytoplasmic hydrolysate fraction. Clinical isolates were grown under optimal conditions and then subjected to 4°C conditions for a period of 8 wks. Cold-stressed and reference control samples were assessed under transmission electron microscopy (TEM) to identify potential ultra-structural changes. To determine changes in amino acid composition, cells were fractured to remove the lipid and cytoplasmic components and the remaining structural components were hydrolysed. Amino acid profiles for the hydrolysis fraction were then analysed for changes by using principal component analysis (PCA). Exposure of the three staphylococci to prolonged low temperature stress resulted in the formation of increasing proportions of small colony variant (SCV) phenotypes. TEM revealed that SCV cells had significantly thicker and more diffuse cell-walls than their corresponding WT samples for both S. aureus and S. epidermidis, but the changes were not significant for S. lugdunensis. Substantial species-specific alterations in the amino acid composition of the structural hydrolysate fraction were also observed in the cold-treated cells. The data indicated that the staphylococci responded over prolonged periods of cold-stress treatment by transforming into SCV populations. The observed ultra-structural and amino acid changes were proposed to represent response mechanisms for staphylococcal survival amidst hostile conditions, thus maintaining the viability of the

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

    PubMed

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

    2006-01-01

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

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

    SciTech Connect

    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.

  4. Effects of chlorpyrifos on the growth and ultrastructure of green algae, Ankistrodesmus gracilis.

    PubMed

    Asselborn, Viviana; Fernández, Carolina; Zalocar, Yolanda; Parodi, Elisa R

    2015-10-01

    The effect of the organophosphorus insecticide chlorpyrifos on the growth, biovolume, and ultrastructure of the green microalga Ankistrodesmus gracilis was evaluated. Concentrations of 9.37, 18.75, 37.5, 75 and 150mgL(-1) of chlorpyrifos were assayed along with a control culture. At the end of the bioassay the ultrastructure of algal cells from control culture and from cultures exposed to 37.5 and 150mgL(-1) was observed under transmission (TEM) and scanning electron microscopy (SEM). After 24 and 48h, treatments with 75 and 150mgL(-1) inhibited the growth of A. gracilis; whereas after 72 and 96h, all the treatments except at 9.37mgL(-1) significantly affected the algae growth. The effective concentration 50 (EC50) after 96h was 22.44mgL(-1) of chlorpyrifos. After the exposure to the insecticide, an increase in the biovolume was observed, with a larger increase in cells exposed to 75 and 150mgL(-1). Radical changes were observed in the ultrastructure of cells exposed to chlorpyrifos. The insecticide affected the cell shape and the distribution of the crests in the wall. At 37.5mgL(-1) electodense bodies were observed along with an increase in the size and number of starch granules. At 150mgL(-1) such bodies occupied almost the whole cytoplasm together with lipids and remains of thylakoids. Autospores formation occurred normally at 37.5mgL(-1) while at 150mgL(-1) karyokinesis occurred, but cell-separation-phase was inhibited. The present study demonstrates that the exposure of phytoplankton to the insecticide chlorpyrifos leads to effects observed at both cellular and population level.

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

    PubMed Central

    Paul, Mayura; Shetty, Devi Charan

    2013-01-01

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

  6. Effect of Low Temperature on Growth and Ultra-Structure of Staphylococcus spp

    PubMed Central

    Onyango, Laura A.; Dunstan, R. Hugh; Gottfries, Johan; von Eiff, Christof; Roberts, Timothy K.

    2012-01-01

    The effect of temperature fluctuation is an important factor in bacterial growth especially for pathogens such as the staphylococci that have to remain viable during potentially harsh and prolonged transfer conditions between hosts. The aim of this study was to investigate the response of S. aureus, S. epidermidis, and S. lugdunensis when exposed to low temperature (4°C) for prolonged periods, and how this factor affected their subsequent growth, colony morphology, cellular ultra-structure, and amino acid composition in the non-cytoplasmic hydrolysate fraction. Clinical isolates were grown under optimal conditions and then subjected to 4°C conditions for a period of 8 wks. Cold-stressed and reference control samples were assessed under transmission electron microscopy (TEM) to identify potential ultra-structural changes. To determine changes in amino acid composition, cells were fractured to remove the lipid and cytoplasmic components and the remaining structural components were hydrolysed. Amino acid profiles for the hydrolysis fraction were then analysed for changes by using principal component analysis (PCA). Exposure of the three staphylococci to prolonged low temperature stress resulted in the formation of increasing proportions of small colony variant (SCV) phenotypes. TEM revealed that SCV cells had significantly thicker and more diffuse cell-walls than their corresponding WT samples for both S. aureus and S. epidermidis, but the changes were not significant for S. lugdunensis. Substantial species-specific alterations in the amino acid composition of the structural hydrolysate fraction were also observed in the cold-treated cells. The data indicated that the staphylococci responded over prolonged periods of cold-stress treatment by transforming into SCV populations. The observed ultra-structural and amino acid changes were proposed to represent response mechanisms for staphylococcal survival amidst hostile conditions, thus maintaining the viability of the

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

    SciTech Connect

    Terrier, Olivier; Moules, Vincent; Carron, Coralie; Cartet, Gaeelle; Frobert, Emilie; Yver, Matthieu; Traversier, Aurelien; Wolff, Thorsten; Naffakh, Nadia; 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.

  8. Clinorotation Affects the Ultrastructure of Pea Root Mitochondria

    NASA Astrophysics Data System (ADS)

    Brykov, Vasyl

    2011-02-01

    Effects of clinorotation on the mitochondrial ultrastructure in cells of meristem, distal and central elongation zones of 3- and 5-day-old etiolated roots of pea seedling roots were studied. It was shown that mitochondria in cells of examined root growth zones revealed a different sensitivity to clinorotation. The ultrastructure of mitochondria in the meristem and central elongation zone cells did not substantially change in comparison with stationary control. At the same time, changes in the mitochondrial ultrastructure in cells of the distal elongation zone under clinorotation were observed, namely: decrease in the size of mitochondria, as well as increase in both matrix electron density and crista volume. Such changes in the mitochondrial ultrastructure under clinorotation are supposed to display the rearrangements of energy metabolism in cells of the distal elongation zone in these conditions.

  9. Observation on the ultrastructure morphology of HeLa cells treated with ethanol: Statistical analysis.

    PubMed

    Al-Bagdadi, Fakhri; Young, Matthew J; Geaghan, James P; Yao, Shaomian; Barona, Humberto M; Martinez-Ceballos, Eduardo; Yoshimura, Masami

    2016-01-01

    It is estimated that 5.9% of all human deaths are attributable to alcohol consumption and that the harmful use of ethanol ranks among the top five risk factors for causing disease, disability, and death worldwide. Ethanol is known to disrupt phospholipid packing and promote membrane hemifusion at lipid bilayers. With the exception of mitochondria involved in hormone synthesis, the sterol content of mitochondrial membranes is low. As membranes that are low in cholesterol have increased membrane fluidity and are the most easily disordered by ethanol, we hypothesize that mitochondria are sensitive targets for ethanol damage. HeLa cells were exposed to 50 mM ethanol and the direct effects of ethanol on cellular ultrastructure were examined utilizing transmission electron microscopy. Our ultramicroscopic analysis revealed that cells exposed to ethanol harbor fewer incidence of apoptotic morphology; however, significant alterations to mitochondria and to nuclei occurred. We observed statistical increases in the amount of irregular cells and cells with multiple nuclei, nuclei harboring indentations, and nuclei with multiple nucleolus-like bodies. Indeed, our analysis revealed that mitochondrial damage is the most extensive type of cellular damage. Rupturing of cristae was the most prominent damage followed by mitochondrial swelling. Ethanol exposure also resulted in increased amounts of mitochondrial rupturing, organelles with linked membranes, and mitochondria localizing to indentations of nuclear membranes. We theorize that these alterations could contribute to cellular defects in oxidative phosphorylation and, by extension, the inability to generate regular levels of cellular adenosine triphosphate.

  10. Correlation between shell colour and ultrastructure in pheasant eggs.

    PubMed

    Richards, P D; Deeming, D C

    2001-07-01

    1. The histochemistry and ultrastructure of pheasant eggs were compared on the basis of blue or brown shell colour. 2. Differences in lectin histochemistry of the outer shell membrane calcification surface indicate a biochemical disruption of the calcification sites in blue eggs. 3. Significant differences were observed in all aspects of eggshell ultrastructure with blue eggs having thinner shells with structural defects. 4. Poor hatchability of blue eggs may reflect high rates of weight loss associated with a defective eggshell.

  11. Epithelial Proliferation on Curved Toroidal Surfaces

    NASA Astrophysics Data System (ADS)

    Chang, Ya-Wen; Cruz, Ricardo; Fragkopoulos, Alexandros; Marquez, Samantha; Garcia, Andres; Fernandez-Nieves, Alberto

    Cellular environment influences a multitude of cellular functions by providing chemical and physical signals that modulate cell behavior, dynamics, development, and eventually survival. In strongly interacting epithelial cells, cells coordinate their behavior to respond to mechanical constraints in 2D. Local differences in tissue tension has also been shown to impact cell reproduction within an epithelial-cell sheet. Much less is known about how cells respond to out-of-plane curvatures. Here, we describe the proliferation of MDCK on toroidal hydrogel substrates, which unlike spheres or planes, have regions of both positive and negative Gaussian curvature. Additionally, the range of curvatures can be controlled by varying the size and aspect ratio of the torus, allowing us to quantify the relation between substrate curvature and cell proliferation.

  12. [Effects of zhibal dihuang decoction on the pathological changes and the ultrastructure of the testicular tissue in the ureaplasma urealyticum-infected rats].

    PubMed

    Lu, Fang-Guo; He, Qing-Hu; Liu, Chao-Sheng

    2012-03-01

    To study the effects of Zhibai Dihuang Decocion (ZDD) on the pathological changes and the ultrastructure of the testicular tissue in the ureaplasma urealyticum (UU)-infected rats. The UU infected animal models were established by the bladder inoculation. The 45 UU infected SD rats were randomly divided into four groups, i.e., the ZDD treatment group (at the daily dose of 2 g/100 g), the Minocycline group (at the daily dose of 10 mg/100 g), the model group, 15 in each group. Besides, another 15 rats were recruited as the sham-operation group. The medication was started 10 days after vaccination. Equal volume of normal saline was given to rats in the model group and the sham-operation group by gastrogavage for 22 successive days. Rats were sacrificed on the 2nd day of medication discontinuation. The testicle mass index was detected. The ultra-structure and the pathological changes of the testicular tissue were observed by optical microscope and transmission electron microscope. There was no significant difference in the rat testicular mass index (P>0.05). UU infection can lead to the pathological changes such as atrophy of seminiferous tubules, germ cell loss, and reduction of sperm cells in lumen, and to the ultrastructural changes such as spermatogenic cell nuclear membrane shrinkage, nuclear breakdown, and obvious edema of mitochondria. The pathological changes and the ultrastructures were improved in the medication groups. Rm and Rs the were not overlapping, and the difference was statistically significant (P<0.05). Rm, Rzh, and Rx were not overlapping, and the difference was statistically significant (P<0.05). Rzh and Rx were overlapping in 95% Cl with no statistical difference (P>0.05). UU infection can cause the pathological changes and the ultrastructural changes of the testicular tissue at the organic level and the cellular level. ZDD played therapeutic effects through ameliorating its pathological changes and the ultrastructural changes of spermatogenic

  13. Cellular senescence: when bad things happen to good cells.

    PubMed

    Campisi, Judith; d'Adda di Fagagna, Fabrizio

    2007-09-01

    Cells continually experience stress and damage from exogenous and endogenous sources, and their responses range from complete recovery to cell death. Proliferating cells can initiate an additional response by adopting a state of permanent cell-cycle arrest that is termed cellular senescence. Understanding the causes and consequences of cellular senescence has provided novel insights into how cells react to stress, especially genotoxic stress, and how this cellular response can affect complex organismal processes such as the development of cancer and ageing.

  14. Endoscopic appearance of GERD: putative role of cell proliferation.

    PubMed

    Calabrese, C; Trerè, D; Fabbri, A; Cenacchi, G; Vici, M; Derenzini, M; Di Febo, G

    2007-08-01

    Erosive esophagitis is a frequent endoscopic feature in patients with gastro-oesophageal reflux disease. However, most of patients with heartburn/regurgitation have a non-erosive reflux disease. The reason for this heterogeneous impact of gastro-oesophageal reflux disease on oesophageal mucosa is unknown to date. To evaluate the cell proliferation status of oesophageal epithelium in both healthy normal subjects and patients with gastro-oesophageal reflux disease with or without erosions. All the subjects underwent endoscopy and biopsies were taken at 5 cm from the squamo-columnar junction. Specimens were analysed both at histology and at transmission electron microscopy. Cell proliferation was evaluated by MIB1 immunostaining. Of the 85 subjects were studied, 10 were healthy controls with normal pH-testing and macroscopical, histological and ultrastructural patterns; 37 were patients with erosive esophagitis, and 38 patients with non-erosive reflux disease. At histology, of the 37 patients affected by erosive esophagitis, 30 had normal mucosa and 7 showed mild oesophagitis. One patient with non-erosive reflux disease showed signs of oesophagitis at histology. At TEM, all patients with gastro-oesophageal reflux disease had ultrastructural patterns of damage i.e. dilations of intercellular spaces (DIS), and all controls had a normal ultrastructural pattern. The mean (+/-SD) MIB1-LI values of normal subjects and non-erosive reflux disease and erosive oesophagitis patients were 62.2% (+/-9.1), 29.7% (+/-7.2) and 16.2% (+/-5.2), respectively; there were significant differences among the three groups (p<0.001). Oesophageal mucosa of patients with reflux symptoms presents a decrease in MIB1 immunostaining of 50% and 25% in non-erosive reflux disease and erosive esophagitis patients with respect to normal subjects.

  15. Fractal Dimensions of In Vitro Tumor Cell Proliferation

    PubMed Central

    Lambrou, George I.

    2015-01-01

    Biological systems are characterized by their potential for dynamic adaptation. One of the challenges for systems biology approaches is their contribution towards the understanding of the dynamics of a growing cell population. Conceptualizing these dynamics in tumor models could help us understand the steps leading to the initiation of the disease and its progression. In vitro models are useful in answering this question by providing information over the spatiotemporal nature of such dynamics. In the present work, we used physical quantities such as growth rate, velocity, and acceleration for the cellular proliferation and identified the fractal structures in tumor cell proliferation dynamics. We provide evidence that the rate of cellular proliferation is of nonlinear nature and exhibits oscillatory behavior. We also calculated the fractal dimensions of our cellular system. Our results show that the temporal transitions from one state to the other also follow nonlinear dynamics. Furthermore, we calculated self-similarity in cellular proliferation, providing the basis for further investigation in this topic. Such systems biology approaches are very useful in understanding the nature of cellular proliferation and growth. From a clinical point of view, our results may be applicable not only to primary tumors but also to tumor metastases. PMID:25883653

  16. Effects of ozone on membrane permeability and ultrastructure in Pseudomonas aeruginosa.

    PubMed

    Zhang, Y Q; Wu, Q P; Zhang, J M; Yang, X H

    2011-10-01

    To examine the mechanism of ozone-induced damage to cytoplasmic membrane and cell ultrastructure of Pseudomonas aeruginosa ATCC27853. Cell suspensions of Ps. aeruginosa ATCC27853 were treated with ozonated water. The leakages of cellular potassium (K⁺), magnesium (Mg²⁺) and adenosine triphosphate (ATP), determined by inductively coupled plasma/mass spectrometry (ICP/MS) and a commercial bioluminescence assay kit, were to assess ozone-induced damage to the cytoplasmic membrane. Maximum leakages of K⁺ and Mg²⁺ were attained, respectively, at 0·53 mg l⁻¹ ozone after 0·5 and 2 min with > 99% inactivation of culturable bacteria, while that of ATP was achieved at 0·67 mg l⁻¹ ozone after 1 min. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) revealed that treated cells retained intact shapes and cytoplasm agglutinations and vacuoles occurred. Ozone inactivates Ps. aeruginosa ATCC27853 by the combined results of increased cytoplasmic membrane permeability and cytoplasm coagulation, rather than by severe membrane disruption and cell lysis. Pseudomonas aeruginosa is a common water-related pathogen. These insights into the leakage of cytoplasmic components and ultrastructural changes provide evidence for the mechanisms of ozone-mediated inactivation. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

  17. Ultrastructure of spermiogenesis in the Cottonmouth, Agkistrodon piscivorus (Squamata: Viperidae: Crotalinae).

    PubMed

    Gribbins, Kevin M; Rheubert, Justin L; Anzalone, Marla L; Siegel, Dustin S; Sever, David M

    2010-03-01

    To date multiple studies exist that examine the morphology of spermatozoa. However, there are limited numbers of data detailing the ontogenic characters of spermiogenesis within squamates. Testicular tissues were collected from Cottonmouths (Agkistrodon piscivorus) and tissues from spermiogenically active months were analyzed ultrastructurally to detail the cellular changes that occur during spermiogenesis. The major events of spermiogenesis (acrosome formation, nuclear elongation/DNA condensation, and flagellar development) resemble that of other squamates; however, specific ultrastructural differences can be observed between Cottonmouths and other squamates studied to date. During acrosome formation vesicles from the Golgi apparatus fuse at the apical surface of the nuclear membrane prior to making nuclear contact. At this stage, the acrosome granule can be observed in a centralized location within the vesicle. As elongation commences the acrosome complex becomes highly compartmentalized and migrates laterally along the nucleus. Parallel and circum-cylindrical microtubules (components of the manchette) are observed with parallel microtubules outnumbering the circum-cylindrical microtubules. Flagella, displaying the conserved 9 + 2 microtubule arrangement, sit in nuclear fossae that have electron lucent shoulders juxtaposed on either side of the spermatids basal plates. This study aims to provide developmental characters for squamates in the subfamily Crotalinae, family Viperidae, which may be useful for histopathological studies on spermatogenesis in semi-aquatic species exposed to pesticides. Furthermore, these data in the near future may provide morphological characters for spermiogenesis that can be added to morphological data matrices that may be used in phylogenetic analyses.

  18. [Effect of simulating static magnetic field of magnetic attachment on osteoblastic morphology and surface ultrastructure].

    PubMed

    Yao, Wei; Zhao, Yu; Li, Bing-yan; Chao, Yong-lie; DU, Li

    2008-01-01

    To investigate effects of the static magnetic field (SMF) generated by dental magnetic attachment on osteoblastic morphology and surface ultrastructure. The in vitro cultured rat osteoblasts were exposed continuously to 12.5 mT, 125 mT, and 250 mT static magnetic fields for 1, 3, 5, and 7 days. After exposed in SMF, osteoblasts were observed under a phase contrast microscope, and then HE stained and observed under a light microscope. In addition, the cells were observed under a scanning electron microscope (SEM). By continuous exposure, the different intensities of SMF exposure did not change the vital osteoblast growth pattern or distribution. The SEM photos showed that there were certain changes in cellular microstructures for osteoblasts after exposed to 12.5 mT for 5 to 7 days, as well as 125 mT and 250 mT for 3 to 7 days. The more exposure time increased, the more microvesicles on the surfaces of cells were observed. Continuous SMF-stimulation could not affect the shape, distribution, and growth pattern of osteoblasts. The SMF of magnetic attachments could lead to certain changes in surface ultrastructures of osteoblasts in this study.

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

    PubMed

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

    2016-11-01

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

  20. Hepatoblastoma. Report of a case with cytologic, histologic and ultrastructural findings.

    PubMed

    Cangiarella, J; Greco, M A; Waisman, J

    1994-01-01

    Hepatoblastoma, although rare, is the most common primary malignant neoplasm of the liver in children. In this paper we describe a case of hepatoblastoma with unusual cytologic features and present the histologic, immunocytochemical and ultrastructural features of this neoplasm. A 7-month-old girl presented with a large hepatic mass and metastatic nodules in both lungs. Intraoperative biopsy revealed a hepatoblastoma. Aspiration biopsy yielded a highly cellular aspirate with cords of pleomorphic cells embedded in a mucoid matrix. Histologic sections showed a diffusely infiltrative neoplasm composed of sheets and cords of highly pleomorphic cells. The neoplastic cells stained strongly positive for cytokeratin CAM 5.2 and AE1 and focally positive for alpha-fetoprotein, ferritin, carcinoembryonic antigen and vimentin. Ultrastructurally, the neoplastic cells had abundant intercellular junctions and intracytoplasmic aggregates of intermediate filaments. A mucoid matrix, to our knowledge, has not been reported as a finding on aspiration biopsy. This patient presented with pulmonary metastases, and thus we think the mucoid matrix may be a marker of a more aggressive variant of hepatoblastoma. This case illustrates additional cytologic features of hepatoblastoma and the usefulness of aspiration biopsy in the rapid diagnosis of this rare tumor.

  1. Ecophysiological and ultrastructural effects of dust pollution in lichens exposed around a cement plant (SW Slovakia).

    PubMed

    Paoli, Luca; Guttová, Anna; Grassi, Alice; Lackovičová, Anna; Senko, Dušan; Sorbo, Sergio; Basile, Adriana; Loppi, Stefano

    2015-10-01

    The study investigated the ecophysiological and ultrastructural effects of dust pollution from a cement industry in the lichen species Evernia prunastri and Xanthoria parietina, which were exposed for 30, 90 and 180 days around a cement mill, two quarries, and inhabited and agricultural sites in SW Slovakia. The results showed that dust deposition from quarrying activities and cement works at the cement mill (mainly enriched in Ca, Fe and Ti) significantly affected the photosynthetic apparatus of E. prunastri (sensitive to dust and habitat eutrophication), while X. parietina (tolerant to dust and habitat eutrophication) adapted to the new environment. The length of the exposure strongly affected the vitality of the mycobiont (measured as dehydrogenase activity) in transplanted lichens. Dust deposition led to ultrastructural alterations, including lipid droplets increase, swelling of cellular components, thylakoid degeneration and sometimes plasmolysis, which, on the whole, gave the cells an aged appearance. Photosynthetic parameters deserve further attention as potential indicators for monitoring early biological symptoms of the air pollution caused during cement production.

  2. Ultrastructural and biochemical changes in alveolar macrophages exposed to nickel hydroxy carbonate.

    PubMed

    Arsalane, K; Hildebrand, H F; Martinez, R; Wallaert, B; Voisin, C

    1994-06-06

    The aim of this investigation was to assess the cytotoxic effect of nickel hydroxy carbonate (NiHC) on guinea pig alveolar macrophages (AMs) by studying ultrastructural modifications and by determining beta-glucuronidase (BG) and lactate dehydrogenase (LDH) activities, as well as cellular ATP content. The ultrastructural studies revealed phagocytosis of NiHC particles and a general vacuolisation of the cells, especially at high concentrations. X-ray microprobe analyses of these particles demonstrated the presence of Ni, P and Ca which suggests the formation of Ni-P-Ca complexes. In exposed cells, a biphasic change in intracellular ATP concentrations was observed which could indicate 'activation' of AMs at low concentrations and inhibition of energy generation at higher concentrations. As for enzymatic activities, a dose-dependent increase in LDH release was observed except at low doses which increased ATP. There was a good correlation between ATP decrease and LDH release, consistent with a dose-dependent cytotoxic effect of NiHC. However beta-glucuronidase activity remained unchanged at all NiHC concentrations. It has been concluded that NiHC undergoes an intracellular, biological transformation to form Ni-P-Ca. Further investigations are needed to determine the precise nature and importance of these complexes.

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

    PubMed

    Omar, Nesreen Moustafa; Mohammed, Mohammed Amin

    2017-06-01

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

  4. Nanoparticles as Alternative Strategies for Drug Delivery to the Alzheimer Brain: Electron Microscopy Ultrastructural Analysis.

    PubMed

    Aliev, Gjumrakch; Daza, Jesús; Herrera, Arturo Solís; del Carmen Arias Esparza, María; Morales, Ludis; Echeverria, Valentina; Bachurin, Sergey Olegovich; Barreto, George Emilio

    2015-01-01

    One of the biggest problems and challenges for the development of new drugs and treatment strategies against Alzheimer Disease (AD) is the crossing of target drugs into the blood brain barrier. The use of nanoparticles in drug delivery therapy holds much promise in targeting remote tissues, and as a result many studies have attempted to study the ultrastructural localization of nanoparticles in various tissues. However, there are currently no in vivo studies demonstrating the ultrastructural distribution of nanoparticles in the brain. The aim of this study was to address how intraperitoneal injection of silver nanoparticles in the brain leads to leaking on the inter-endothelial contact and luminal plasma membrane, thus elucidating the possibility of penetrating into the most affected areas in the Alzheimer brain (vascular endothelium, perivascular, neuronal and glial cells). Our results show that the silver nanoparticles reached the brain and were found in hippocampal areas, indicating that they can be conjugated and used to deliver the drugs into the cell cytoplasm of the damaged brain cells. The present study can be useful for the development of novel drug delivering therapy and useful in understanding the delivery, distribution and effects of silver nanoparticles in AD brain tissue at cellular and subcellular level.

  5. Ultrastructural analysis of rat articular cartilage following treatment with dexamethasone and glycosaminoglycan-peptide complex.

    PubMed

    Annefeld, M; Erne, B; Rasser, Y

    1990-01-01

    This ultrastructural study describes a stereological analysis of rat articular cartilage, with and without exposure to dexamethasone and a chondroprotective drug used in the treatment of osteoarthritis. Normal rat cartilage was found to contain 27.6 x 10(4) chondrocytes/mm3 which occupied approximately 10% of the cartilage tissue, and the organelle content of each chondrocyte was calculated to be about 20% of the cytoplasmic volume. After 3 weeks of treatment with dexamethasone the chondrocytic volume was increased by 23% with a proportionate increase in the cellular volume of the whole cartilage, and in addition the organelle content was significantly reduced to about half that of the control chondrocytes. By contrast the administration of GP-C (RUMALON) to dexamethasone-treated animals reduced these steroid effects. No significant change was seen in the total chondrocyte numbers with either of the treatments. Whereas dexamethasone inhibits chondrocyte metabolism and produces concomitant ultrastructural changes, GP-C was found to counteract these effects, a result which supports the contention that GP-C helps to preserve chondrocyte function.

  6. Synaptic plasticity and gravity: Ultrastructural, biochemical and physico-chemical fundamentals

    NASA Astrophysics Data System (ADS)

    Rahmann, H.; Slenzka, K.; Körtje, K. H.; Hilbig, R.

    On the basis of quantitative disturbances of the swimming behaviour of aquatic vertebrates (``loop-swimming'' in fish and frog larvae) following long-term hyper-g-exposure the question was raised whether or not and to what extent changes in the gravitational vector might influence the CNS at the cellular level. Therefore, by means of histological, histochemical and biochemical analyses the effect of 2-4 x g for 9 days on the gross morphology of the fish brain, and on different neuronal enzymes was investigated. In order to enable a more precise analysis in future-μg-experiments of any gravity-related effects on the neuronal synapses within the gravity-perceptive integration centers differentiated electron-microscopical and electronspectroscopical techniques have been developed to accomplish an ultrastructural localization of calcium, a high-affinity Ca2+-ATPase, creatine kinase and cytochrome oxidase. In hyper-g animals vs. 1-g controls, a reduction of total brain volume (15 %), a decrease in creatine kinase activity (20 %), a local increase in cytochrome oxidase activity, but no differences in Ca2+/Mg2+-ATPase activities were observed. Ultrastructural peculiarities of synaptic contact formation in gravity-related integration centers (Nucleus magnocellularis) were found. These results are discussed on the basis of a direct effect of hyper-gravity not only on the gravity-sensitive neuronal integration centers but possibly also on the physico-chemical properties of the lipid bilayer of neuronal membranes in general.

  7. Ultrastructural changes during lung carcinogenesis-modulation by curcumin and quercetin

    PubMed Central

    Wang, Xin; Wang, Lei; Zhang, Hao; Li, Ke; You, Jiqin

    2016-01-01

    The aim of the present study was to examine the effectiveness of curcumin and quercetin in modulating ultrastructural changes during lung carcinogenesis. A total of 24 male laka mice were divided into the normal control, benzo[a]pyrene (BP)-treated, BP+curcumin-treated, BP+quercetin- treated, and BP+curcumin+quercetin-treated groups (n=6 per group). Lung carcinogenesis was induced by a single intraperitoneal injection of BP [100 mg/kg of body weight (b.wt.)]. Curcumin was supplemented to mice at a dose level of 60 mg/kg of b.wt. in drinking water and quercetin was given at a dose level of 40 mg/kg of b.wt. in drinking water. The ultrastructure of BP-treated mice revealed disruptions in cellular integrity together with nuclear deformation and premature mitochondrial aging. Notably, supplementation with phytochemicals individually resulted in improvement of the ultra-histoarchitecture of BP-treated mice although the improvement was much greater with combined supplementation of phytochemicals. Furthermore, BP treatment revealed alterations in lung histoarchitecture, which, however, were improved appreciably following combined supplementation with curcumin and quercetin. The results of the present study show that, combined supplementation with curcumin and quercetin effectively preserved the histoarchitecture as well as ultra-histoarchitecture during BP-induced lung carcinogenesis in mice. PMID:28101199

  8. Molecular and ultrastructural studies of a fibrillar collagen from octocoral (Cnidaria).

    PubMed

    Orgel, Joseph P R O; Sella, Ido; Madhurapantula, Rama S; Antipova, Olga; Mandelberg, Yael; Kashman, Yoel; Benayahu, Dafna; Benayahu, Yehuda

    2017-07-13

    We report here the biochemical, molecular and ultrastructural features of a unique organization of fibrillar collagen extracted from the octocoral Sarcophyton ehrenbergi Collagen, the most abundant protein in the animal kingdom, is often defined as a structural component of extra-cellular matrices in metazoans. In the present study, collagen fibers were extracted from the mesenteries of S. ehrenbergi polyps. These fibers are organized as filaments and further compacted as coiled fibers. The fibers are uniquely long, reaching an unprecedented length of tens of centimeters. The diameter of these fibers is 9 ±0.37 µm.The amino acid content of these fibers was identified using chromatography and revealed close similarity in content to mammalian type I and II collagens. The ultrastructural organization of the fibers was characterized by means of high resolution microscopy and X-ray diffraction. The fibers are composed of fibrils and fibril bundles in the range of 15 to 35 nm. These data indicate a fibrillar collagen possessing structural aspects of both types I and II, a highly interesting and newly described form of fibrillar collagen organization. © 2017. Published by The Company of Biologists Ltd.

  9. Ultrastructural changes during lung carcinogenesis-modulation by curcumin and quercetin.

    PubMed

    Wang, Xin; Wang, Lei; Zhang, Hao; Li, Ke; You, Jiqin

    2016-12-01

    The aim of the present study was to examine the effectiveness of curcumin and quercetin in modulating ultrastructural changes during lung carcinogenesis. A total of 24 male laka mice were divided into the normal control, benzo[a]pyrene (BP)-treated, BP+curcumin-treated, BP+quercetin- treated, and BP+curcumin+quercetin-treated groups (n=6 per group). Lung carcinogenesis was induced by a single intraperitoneal injection of BP [100 mg/kg of body weight (b.wt.)]. Curcumin was supplemented to mice at a dose level of 60 mg/kg of b.wt. in drinking water and quercetin was given at a dose level of 40 mg/kg of b.wt. in drinking water. The ultrastructure of BP-treated mice revealed disruptions in cellular integrity together with nuclear deformation and premature mitochondrial aging. Notably, supplementation with phytochemicals individually resulted in improvement of the ultra-histoarchitecture of BP-treated mice although the improvement was much greater with combined supplementation of phytochemicals. Furthermore, BP treatment revealed alterations in lung histoarchitecture, which, however, were improved appreciably following combined supplementation with curcumin and quercetin. The results of the present study show that, combined supplementation with curcumin and quercetin effectively preserved the histoarchitecture as well as ultra-histoarchitecture during BP-induced lung carcinogenesis in mice.

  10. Granulocytes of reptilian sauropsids contain beta-defensin-like peptides: a comparative ultrastructural survey.

    PubMed

    Alibardi, Lorenzo

    2013-08-01

    The ability of lizards to withstand infections after wounding or amputation of the tail or limbs has suggested the presence of antimicrobial peptides in their tissues. Previous studies on the lizard Anolis carolinensis have identified several beta-defensin-like peptides that may potentially be involved in protection from infections. The present ultrastructural immunocytochemical study has analyzed tissues in different reptilian species in order to localize the cellular source of one of the more expressed beta-defensins previously sequenced in lizard indicated as AcBD15. Beta-defensin-like immunoreactivity is present in some of the larger, nonspecific granules of granulocytes in two lizard species, a snake, the tuatara, and a turtle. The ultrastructural study indicates that only heterophilic and basophilic granulocytes contain this defensin while other cell types from the epidermis, mesenchyme, and dermis, muscles, nerves, cartilage or bone are immunonegative. The study further indicates that not all granules in reptilian granulocytes contain the beta-defensin peptide, suggesting the presence of granules with different content as previously indicated for mammalian neutrophilic leucocytes. No immunolabeling was instead observed in granulocytes of the alligator and chick using this antibody. The present immunocytochemical observations suggest a broad cross-reactivity and conservation of beta-defensin-like sequence or steric motif across lepidosaurians and likely in turtles while archosaurian granulocytes may contain different beta-defensin-like or other peptides. Copyright © 2013 Wiley Periodicals, Inc.

  11. Histomorphometric and ultrastructural analysis of the tendon-bone interface after rotator cuff repair in a rat model

    PubMed Central

    Kanazawa, Tomonoshin; Gotoh, Masafumi; Ohta, Keisuke; Honda, Hirokazu; Ohzono, Hiroki; Shimokobe, Hisao; Shiba, Naoto; Nakamura, Kei-ichiro

    2016-01-01

    Successful rotator cuff repair requires biological anchoring of the repaired tendon to the bone. However, the histological structure of the repaired tendon-bone interface differs from that of a normal tendon insertion. We analysed differences between the normal tendon insertion and the repaired tendon-bone interface after surgery in the mechanical properties, histomorphometric analysis, and 3-dimensional ultrastructure of the cells using a rat rotator cuff repair model. Twenty-four adult Sprague-Dawley (SD) rats underwent complete cuff tear and subsequent repair of the supraspinatus tendon. The repaired tendon-bone interface was evaluated at 4, 8, and 12 weeks after surgery. At each time point, shoulders underwent micro-computed tomography scanning and biomechanical testing (N = 6), conventional histology and histomorphometric analysis (N = 6), and ultrastructural analysis with focused ion beam/scanning electron microscope (FIB/SEM) tomography (N = 4). We demonstrated that the cellular distribution between the repaired tendon and bone at 12 weeks after surgery bore similarities to the normal tendon insertion. However, the ultrastructure of the cells at any time point had a different morphology than those of the normal tendon insertion. These morphological differences affect the healing process, partly contributing to re-tearing at the repair site. These results may facilitate future studies of the regeneration of a normal tendon insertion. PMID:27647121

  12. Spent metal working fluids produced alterations on photosynthetic parameters and cell-ultrastructure of leaves and roots of maize plants.

    PubMed

    Grijalbo, Lucía; Fernandez-Pascual, Mercedes; García-Seco, Daniel; Gutierrez-Mañero, Francisco Javier; Lucas, Jose Antonio

    2013-09-15

    In this work we assess the capacity of maize (Zea mays) plants to phytoremediate spent metal working fluids (MWFs) and its effects on photosynthesis and ultrastructure of mesophyll and root cells. A corn-esparto fibre system patented by us has been used to phytoremediate MWFs in hydroponic culture. Furthermore, a plant growth promoting rhizobacteria (PGPR) has been used to improve the process. The results show that this system is capable of significantly reducing the chemical oxygen demand, under local legislation limits. However, plant systems are really damaged, mainly its photosynthetic system, as shown by the photosynthetical parameters. Nevertheless, strain inoculated improves these parameters, especially Hill reaction. The ultrastructure of photosynthetic apparatus was also affected. Chloroplast number decreased and becomes degraded in the mesophyll of MWFs treated plants. In some cases even plasmolysis of chloroplast membrane was detected. Early senescence symptoms were detected in root ultrastructural study. Severe cellular damage was observed in the parenchymal root cells of plants grown with MWFs, while vascular bundles cell remained unchanged. It seems that the inoculation minimises the damage originated by the MWFs pollutants, appearing as less degenerative organelles and higher chloroplast number than in non-inoculated ones. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Effect of the photoperiod and administration of melatonin on the pars tuberalis of viscacha (Lagostomus maximus maximus): an ultrastructural study.

    PubMed

    Romera, Edith Perez; Mohamed, Fabian; Fogal, Teresa; Dominguez, Susana; Piezzi, Ramón; Scardapane, Luis

    2010-05-01

    The pituitary pars tuberalis (PT) is a glandular zone exhibiting well-defined structural characteristics. Morphologically, it is formed by specific secretory cells, folliculostellate cells, and migratory cells coming from the pars distalis. The purpose of this work was to investigate differences in specific cellular characteristics in the PT of viscachas captured in summer (long photoperiod) and winter (short photoperiod), as well as the effects of chronic melatonin administration in viscachas captured in summer and kept under long photoperiod. In summer, the PT-specific cells exhibited cell-like characteristics with an important secretory activity and a moderate amount of glycogen. In winter, the PT-specific granulated cells showed ultrastructural variations with signs of a reduced synthesis activity. Also, PT showed a high amount of glycogen and a great number of cells in degeneration. After melatonin administration, the ultrastructural characteristics were similar to those observed in winter, but the amount of glycogen was higher. These results suggest possible functional implications as a result of morphological differences between long and short photoperiods, and are in agreement with the variations of the pituitary-gonadal axis, probably in response to the natural photoperiod changes through the pineal melatonin. The ultrastructural differences observed in PT, after melatonin administration, were similar to those observed in the short photoperiod, thus supporting the hypothesis that these cytological changes are induced by melatonin.

  14. Cytological, immunocytochemical and ultrastructural study of the adenohypophyseal pars distalis of the kid (Capra hircus): the TSH cell.

    PubMed

    Gomez, M A; Navarro, J A; Gomez, S; Camara, P; Gomez, J C; Bernabé, A

    1989-12-01

    The structure and ultrastructure of the adenohypophyseal pars distalis in kids of the Murciano-granadiana breed (18 males and 12 females), aged 2-3 months and with an average carcass weight of 8 kg has been studied. Techniques of staining (Tetrachrome Herlant's, and Cleveland-Wolfe) and histochemistry (PAS, PAS-OG and BA-PAS-OG) contrasted with immunolabelling (PAP) have been used. In addition an ultrastructural study has been made and nucleus and cytoplasm, secretory granules, mitochondria and lysosomes have been measured with a semiautomatic image analyzer (IBAS-1). TSH cells are found in sagittal section in the anterior area and in an antero-caudodorsal band, and transversally in the ventral and medial region; they are 6% and their average size is 14.15 microns. Ultrastructurally they are a single cellular type with spherical granules whose size is 195 nm in males and 149 in females; these granules are characterized by a clear halo and a variable electronic density. The rough endoplasmic reticulum is found as slightly enlarged vesicles with a homogeneous and moderately electro-dense content or in concentric stratifications.

  15. Immunocytochemical and ultrastructural characterization of endocrine cells in the larval stomach of the frog Rana temporaria tadpoles: a comparison with adult specimens.

    PubMed

    Villaro, A C; Rovira, J; Bodegas, M E; Burrell, M A; García-Ros, D; Sesma, P

    2001-10-01

    According to immunostaining and ultrastructural patterns, Rana temporaria tadpole stomach displays a well-differentiated endocrine population comprising, at least, six cellular types: ECL, EC [serotonin], D [somatostatin] - all three of them abundant -, P [bombesin] - less numerous -, CCK-8 [cholecystokinin/gastrin] and A [glucagon/glicentin] - both very scarce. Larval endocrine cells are mainly located in the surface epithelium and show open or closed morphologies. Cellular diversity is similar in tadpoles and frogs, with the exception of immunoreactivity for gastrin-17, found in adults in numerous cells. Larval cells display mature ultrastructural traits, although with smaller secretory granules. The different distribution of endocrine cells, which in adults are preferentially located in the glands, probably refers to different functional requirements. However, the rich vascular plexus present in larval mucosa may be an efficient transport medium of surface hormones to-gastric targets. The enhancement in adults of endocrine population and correlative increase in hormonal secretion indicates a more active functional role, probably related to the shift from herbivorous to carnivorous habits. In summary, the tadpole gastric endocrine population, although not as numerous as that of adult frogs, displays histological traits that indicate a relevant (immunoreactive and ultrastructural properties, cellular diversity) and specific (surface location, relative abundance of open-type cells) role of local regulatory factors in amphibian larval gastric function.

  16. Ultrastructural modification of the ciliate protozoan, Colpidium colpoda following chronic exposure to partially degraded crude oil

    SciTech Connect

    Rogerson, A.; Berger, J.

    1982-06-01

    Protozoa are important consumers of the microflora that biodegrade oil spills. In the study presented, the ultrastructural effects induced by chronic oil stress in the ciliate protozoan, Colpidium colpoda are discussed. Colpidia were grown in control cultures containing a dilute organic medium and a dense suspension of prey bacteria. After 20 days' oil exposure, C. colpoda contained more stained cytoplasmic inclusions than ciliates grown in the control media. Although the extent of Sudan Black staining in the oil-stressed cells indicates the presence of lipids, these droplets are better termed lipid-hydrocarbon (LH) inclusions until their definitive composition is known. C. colpoda accumulated significant quantities of lipid-hydrocarbons accounting for up to 20% of their cellular volume. Studies are currently being conducted to characterized these inclusions and to evaluate the effects of feeding these ''oil-labeled'' prey to predators, an important issue with the increasing concern about the biomagnification of environmental pollutants. (JMT)

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

    PubMed

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

    2011-01-01

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

  18. Macrophage Autophagy and Oxidative Stress: An Ultrastructural and Immunoelectron Microscopical Study

    PubMed Central

    Perrotta, Ida; Carito, Valentina; Russo, Emilio; Tripepi, Sandro; Aquila, Saveria; Donato, Giuseppe

    2011-01-01

    The word autophagy broadly refers to the cellular catabolic processes that lead to the removal of damaged cytosolic proteins or cell organelles through lysosomes. Although autophagy is often observed during programmed cell death, it may also serve as a cell survival mechanism. Accumulation of reactive oxygen species within tissues and cells induces various defense mechanisms or programmed cell death. It has been shown that, besides inducing apoptosis, oxidative stress can also induce autophagy. To date, however, the regulation of autophagy in response to oxidative stress remains largely elusive and poorly understood. Therefore, the present study was designed to examine the ratio between oxidative stress and autophagy in macrophages after oxidant exposure (AAPH) and to investigate the ultrastructural localization of beclin-1, a protein essential for autophagy, under basal and stressful conditions. Our data provide evidence that oxidative stress induces autophagy in macrophages. We demonstrate, for the first time by immunoelectron microscopy, the subcellular localization of beclin-1 in autophagic cells. PMID:21922037

  19. Ultrastructural analyses support different morphological lineages in the phylum Placozoa Grell, 1971.

    PubMed

    Guidi, Loretta; Eitel, Michael; Cesarini, Erica; Schierwater, Bernd; Balsamo, Maria

    2011-03-01

    The morphology and ultrastructure of 10 clonal placozoan lineages were studied. We scored several morphological characters at a cellular and intracellular level and identified a number of morphological differences among clones. Some differences appear clone specific and allow recognizing five distinct lineages based on morphological criteria only. These data will be crucial for a yet to be established placozoan systematics. Furthermore, we here describe three new diagnostic morphological characters for Placozoa: a new structure in the upper epithelium, called "concave disc," two distinct subpopulations of fiber cells, and especially small cells in the body margin. Besides the fiber cells appear to be arranged in several layers forming a complex, three-dimensional net not previously described. We also describe the marginal cells as the formerly suggested potential stem-cell type. The basic morphology is revised. Copyright © 2011 Wiley-Liss, Inc.

  20. Resolving new ultrastructural features of cytokinetic abscission with soft-X-ray cryo-tomography

    PubMed Central

    Sherman, Shachar; Kirchenbuechler, David; Nachmias, Dikla; Tamir, Adi; Werner, Stephan; Elbaum, Michael; Elia, Natalie

    2016-01-01

    Mammalian cytokinetic abscission is mediated by the ESCRT membrane fission machinery. While much has been clarified on the topology and kinetics of abscission through high-resolution microscopy, key questions regarding the mechanism of abscission remain open. Here we apply cryogenic soft-X-ray tomography to elucidate new ultrastructural details in the intercellular membrane bridge connecting cells undergoing abscission. In particular, we resolve defined ring-like structures inside the midbody dark zone that have been inaccessible to EM, and identify membrane extrusions at the abscission sites. In cells at late stages of abscission we resolve a complex array of helical spirals, extending the structural information obtained by EM. Our results highlight the advantages of soft-X-ray tomography and emphasize the importance of using complementary approaches for characterizing cellular structures. Notably, by providing new structural data from intact cells we present a realistic view on the topology of abscission and suggest new mechanistic models for ESCRT mediated abscission. PMID:27282220

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

    PubMed Central

    Hernández-Fonseca, Juan P.; Rincón, Jaimar; Pedreañez, Adriana; Viera, Ninoska; Arcaya, José L.; Carrizo, Edgardo; Mosquera, Jesús

    2009-01-01

    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. PMID:19812703

  2. Preparation of cells for assessing ultrastructural localization of nanoparticles with transmission electron microscopy.

    PubMed

    Schrand, Amanda M; Schlager, John J; Dai, Liming; Hussain, Saber M

    2010-04-01

    We describe the use of transmission electron microscopy (TEM) for cellular ultrastructural examination of nanoparticle (NP)-exposed biomaterials. Preparation and imaging of electron-transparent thin cell sections with TEM provides excellent spatial resolution (approximately 1 nm), which is required to track these elusive materials. This protocol provides a step-by-step method for the mass-basis dosing of cultured cells with NPs, and the process of fixing, dehydrating, staining, resin embedding, ultramicrotome sectioning and subsequently visualizing NP uptake and translocation to specific intracellular locations with TEM. In order to avoid potential artifacts, some technical challenges are addressed. Based on our results, this procedure can be used to elucidate the intracellular fate of NPs, facilitating the development of biosensors and therapeutics, and provide a critical component for understanding NP toxicity. This protocol takes approximately 1 week.

  3. Ultrastructural Complexity of Nuclear Components During Early Apoptotic Phases in Breast Cancer Cells

    PubMed Central

    Castelli, Christian; Losa, Gabriele A.

    2001-01-01

    Fractal morphometry was used to investigate the ultrastructural features of the plasma membrane, perinuclear membrane and nuclear chromatin in SK‐BR‐3 human breast cancer cells undergoing apoptosis. Cells were incubated with 1 μM calcimycin (A23187) for 24 h. Cells in the early stage of apoptosis had fractal dimension (FD) values indicating that their plasma membranes were less rough (lower FD) than those of control cells, while their perinuclear membranes were unaffected. Changes of the chromatin texture within the entire nucleus and in selected nuclear domains were more pronounced in treated cells. This confirms that the morphological reorganization imputable to a loss of structural complexity (reduced FD) occurs in the early stage of apoptosis, is accompanied by the inhibition of distinct enzymatic events and precedes the onset of conventional cellular markers, which can only be detected during the active phases of the apoptotic process. PMID:11790854

  4. Pyrazole prevention of CC14-induced ultrastructural changes in rat liver.

    PubMed Central

    Bernacchi, A. S.; de Castro, C. R.; de Toranzo, E. G.; Marzi, A.; de Ferreyra, E. C.; de Fenos, O. M.; Castro, J. A.

    1980-01-01

    Carbon tetrachloride (CC14) administration to rats leads to an early dilatation, vesiculation and disorganization of the liver endoplasmic reticulum (ER). This hepatotoxin also causes detachment of ribosomes from ER membranes, dilatation of the Golgi cisternae and occasionally dilatation of the perinuclear membrane. Prior treatment of the rats with pyrazole completely prevents CC14- induced ultrastructural alterations observed in liver at 3 h. This drug is known to decrease the intensity of the irreversible binding of CC14 reactive metabolites to cellular constituents without modifying the intensity of the CC14- induced lipid peroxidation, either in vitro or in vivo, as measured by the diene conjugation procedure or by decreases inthe arachidonic acid content of microsomal phospholipids. Results suggest that interaction of reactive metabolites rather than lipid peroxidation mediates deleterious effects of CCl4 on the liver ER. Images Fig. 1 Fig. 2 Fig. 3 PMID:7448119

  5. New, improved lanthanide-based methods for the ultrastructural localization of acid and alkaline phosphatase activity.

    PubMed

    Halbhuber, K J; Zimmermann, N; Linss, W

    1988-01-01

    New, improved techniques for the ultrastructural localization of acid and alkaline phosphatase activity using lanthanide cations as the trapping agent were developed. Delayed penetration of the capture ions and the incubation constituents into cellular compartments was prevented by pretreating specimens with borohydride/saponin. Both the concentration of the capture agent in the incubation medium and the incubation time of the tissue specimens were optimized to achieve a satisfactory cytochemical reaction and to avoid precipitation artefacts caused by local matrix effects. The conversion of cerium phosphate into the almost insoluble cerium fluoride minimized losses of the reaction product during postincubation processing. Moreover, lanthanum itself as well as lanthanides other than cerium, e.g., gadolinium and didymium (praseodymium, neodymium), were successfully applied and can be recommended as capture agents for phosphatase cytochemistry.

  6. Spermatozoon ultrastructure in two monorchiid digeneans.

    PubMed

    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. T