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1

Electron Microscope Studies of Experimental Entamoeba Histolytica Infection in the Guinea Pig. II. Early Cellular and Vascular Changes Accompanying Invasion of the Lamina Propria.  

National Technical Information Service (NTIS)

Early cellular and vascular changes in response to invasion of the lamina propria by E. histolytica were studied ultrastructurally in the guinea pig innoculated with amebae and enteric flora from patients with acute colitis. Approximately one week post in...

A. Takeuchi B. P. Phillips

1975-01-01

2

Morphological properties of collagen fibers in porcine lamina propria  

PubMed Central

Objectives Collagen influences the biomechanical properties of vocal folds. Altered collagen morphology has been implicated in dysphonia associated with aging and scarring. Documenting the morphological properties of native collagen in healthy vocal folds is essential to understand the structural and functional alterations to collagen with aging and disease. Our primary objective was to quantify the morphological properties of collagen in the vocal fold lamina propria. Our secondary exploratory objective was to investigate the effects of pepsin exposure on the morphological properties of collagen in the lamina propria. Design Experimental, in vitro study with porcine model. Methods Lamina propria was dissected from 26 vocal folds and imaged with Atomic Force Microscopy (AFM). Morphological data on d-periodicity, diameter, and roughness of collagen fibers were obtained. To investigate the effects of pepsin exposure on collagen morphology, vocal fold surface was exposed to pepsin or sham challenge prior to lamina propria dissection and AFM imaging. Results The d-periodicity, diameter, and roughness values for native vocal fold collagen are consistent with literature reports for collagen fibers in other body tissue. Pepsin exposure on vocal fold surface did not appear to change the morphological properties of collagen fibers in the lamina propria. Conclusions Quantitative data on collagen morphology were obtained at nanoscale resolution. Documenting collagen morphology in healthy vocal folds is critical for understanding the physiological changes to collagen with aging and scarring, and for designing biomaterials that match the native topography of lamina propria.

Johanes, Iecun; Mihelc, Elaine; Sivasankar, Mahalakshmi; Ivanisevic, Albena

2009-01-01

3

Cellular architecture of the lamina propria of human seminiferous tubules  

Microsoft Academic Search

The lamina propria of human seminiferous tubules is composed of 5 to 7 cellular layers separated by laminae of extracellular connective-tissue components. By means of immunocytochemical methods the different nature of the cellular layers could be defined for the first time. Based on the light-microscopic demonstration of both desmin-like and vimentin-like immunoreactivity in the inner 3 to 4 layers of

M. S. Davidoff; H. Breucker; A. F. Holstein; K. Seidl

1990-01-01

4

Characterizing lamina propria of human gastric mucosa by multiphoton microscopy  

NASA Astrophysics Data System (ADS)

Lamina propria (LP) of gastric mucosa plays an important role in progression of gastric cancer because of the site at where inflammatory reactions occur. Multiphoton imaging has been recently employed for microscopic examination of intact tissue. In this paper, using multiphoton microscopy (MPM) based on two-photon excited fluorescence (TPEF) and second harmonic generation (SHG), high resolution multiphoton microscopic images of lamina propria (LP) are obtained in normal human gastric mucosa at excitation wavelength ?ex = 800 nm. The main source of tissue TPEF originated from the cells of gastric glands, and loose connective tissue, collagen, produced SHG signals. Our results demonstrated that MPM can be effective for characterizing the microstructure of LP in human gastric mucosa. The findings will be helpful for diagnosing and staging early gastric cancer in the clinics.

Liu, Y. C.; Yang, H. Q.; Chen, G.; Zhuo, S. M.; Chen, J. X.; Yan, J.

2011-01-01

5

Dinitrochlorobenzene-induced colitis in the guinea-pig: studies of colonic lamina propria lymphocytes.  

PubMed Central

Dinitrochlorobenzene-induced colitis in guinea-pigs may be immunologically mediated: animals must be presensitised to dinitrochlorobenzene to develop colitis, sensitivity can be passively transferred by lymphocytes and the injury can be mitigated by immunosuppression. In this study, we examined lamina propria lymphocytes isolated from colons of animals with dinitrochlorobenzene-induced colitis, and appropriate controls. Lamina propria lymphocytes from colitis animals have a greater percentage of rabbit erythrocyte-rosetting cells (T cells) (20.1 +/- 3.0 vs 2.3 +/- 0.8, p less than .01) and a greater capacity to mediate mitogen-induced cellular cytotoxicity with phytohaemagglutinin than lamina propria lymphocytes from normal colon (% specific cytoxicity = 29.4 +/- 8.7 vs 5.0 +/- 4.5, P less than .005). There was no difference in the percentage of rosetting cells or cytotoxicity index of spleen or mesenteric lymph node lymphocytes between the colitis animals and controls. These data suggest that there are changes in the distribution and functional characteristics of lamina propria lymphocytes which correlate with mucosal cell injury in the dinitrochlorobenzene-colitis model. Images Figure

Glick, M E; Falchuk, Z M

1981-01-01

6

Preparation and purification of lymphocytes from the epithelium and lamina propria of murine small intestine  

Microsoft Academic Search

Existing methods for the production of lymphocytes from the small intestine have proved unsatisfactory when applied to the mouse. We report here a new method for the production of highly pure suspensions of lymphoid cells from the epithelial layer and lamina propria of mouse small intestine. The production and purification methods are described in detail. At least ten million lymphocytes

M D Davies; D M Parrott

1981-01-01

7

Dendritic cells, the major antigen-presenting cells of the human colonic lamina propria.  

PubMed Central

Induction of T-cell responses requires the recognition of antigen in association with class II major histocompatibility complex (MHC) antigens on specialized antigen-presenting cells. It was previously demonstrated that dendritic cells were the major antigen-presenting cell in the mouse intestinal lamina propria whilst macrophages were shown to be suppressive. The aim of this study was to compare the antigen-presenting cell activity of human colonic dendritic cells with macrophages. Colonic mucosa was removed from 46 specimens resected for cancer and other non-malignant conditions and lamina propria cell suspensions obtained by EDTA treatment followed by enzymatic digestion. Lamina propria cell suspensions, depleted of macrophages by adherence to insolubilized human immunoglobulin and carbonyl iron phagocytosis, were enriched for dendritic cells by density gradient centrifugation. Yields represented 0.9% (range 0.7-1.4%) of the starting cell number and the degree of enrichment was 30-50%. Immunocytochemistry demonstrated high levels of class II MHC antigen expression, but low levels or absent expression of macrophage and other markers. The ultrastructural features of the low-density cell fraction were typical of dendritic cells with cytoplasmic extensions or veils and the absence of phagocytic vesicles. Populations of cells enriched for macrophages were obtained by harvesting the human immunoglobulin-adherent cells. These cells were > 70% positive for macrophage markers using immunocytochemistry. The ability of lamina propria cells to induce primary T-cell activation was assayed using allogeneic peripheral blood T cells as responders in the mixed leucocyte reaction (MLR). When antigen-presenting activity was assessed using the MLR, the stimulatory activity was present in the dendritic cell-enriched fraction, with little activity present in the macrophage fraction. These data indicate that dendritic cells, not macrophages, are the major cell population capable of generating a mixed leucocyte reaction in the human colonic lamina propria. Images Figure 1 Figure 2 Figure 3

Pavli, P; Hume, D A; Van De Pol, E; Doe, W F

1993-01-01

8

Hyperexpression of inducible costimulator and its contribution on lamina propria T cells in inflammatory bowel disease  

Microsoft Academic Search

Background & Aims: To investigate the role of inducible costimulator (ICOS), a new member of the CD28 family involved in regulation of T-cell activation and chronic intestinal inflammation, we assessed its expression and functional role in patients with inflammatory bowel disease (IBD). Methods: Expression of ICOS, CD28, and cytotoxic T-lymphocyte antigen (CTLA) 4 on intestinal lamina propria mononuclear cells (LPMC)

Toshiro Sato; Takanori Kanai; Mamoru Watanabe; Atsushi Sakuraba; Susumu Okamoto; Takaaki Nakai; Akira Okazawa; Nagamu Inoue; Teruji Totsuka; Motomi Yamazaki; Richard A. Kroczek; Tsuneo Fukushima; Hiromasa Ishii; Toshifumi Hibi

2004-01-01

9

Isolation and subsequent analysis of murine lamina propria mononuclear cells from colonic tissue.  

PubMed

Studies on colonic cells in the lamina propria (LP) of mice are important for understanding the cellular and immune responses in the gut, especially in inflammatory bowel diseases (such as morbus crohn and colitis ulcerosa). This protocol details a method to isolate LP cells and characterize freshly isolated cells by quality control experiments to obtain cells that can be used for further investigations. After different steps of digestion of the tissue using collagenase, DNase and dispase, the resulting cells are purified using Percoll gradient. The success of the isolation can be analyzed by cell viability test (Trypan Blue exclusion test) and by flow cytometric analysis to assess apoptosis. Finally, the isolated cells can be used for further investigations like comparative studies of mRNA expression, cell-proliferation assay or protein analysis. This protocol can be completed within 6-7 h. PMID:17947970

Weigmann, Benno; Tubbe, Ingrid; Seidel, Daniel; Nicolaev, Alex; Becker, Christoph; Neurath, Markus F

2007-01-01

10

Intestinal lamina propria dendritic cells maintain T cell homeostasis but do not affect commensalism.  

PubMed

Dendritic cells (DCs) in the intestinal lamina propria (LP) are composed of two CD103(+) subsets that differ in CD11b expression. We report here that Langerin is expressed by human LP DCs and that transgenic human langerin drives expression in CD103(+)CD11b(+) LP DCs in mice. This subset was ablated in huLangerin-DTA mice, resulting in reduced LP Th17 cells without affecting Th1 or T reg cells. Notably, cognate DC-T cell interactions were not required for Th17 development, as this response was intact in huLangerin-Cre I-A?(fl/fl) mice. In contrast, responses to intestinal infection or flagellin administration were unaffected by the absence of CD103(+)CD11b(+) DCs. huLangerin-DTA x BatF3(-/-) mice lacked both CD103(+) LP DC subsets, resulting in defective gut homing and fewer LP T reg cells. Despite these defects in LP DCs and resident T cells, we did not observe alterations of intestinal microbial communities. Thus, CD103(+) LP DC subsets control T cell homeostasis through both nonredundant and overlapping mechanisms. PMID:24019552

Welty, Nathan E; Staley, Christopher; Ghilardi, Nico; Sadowsky, Michael J; Igyártó, Botond Z; Kaplan, Daniel H

2013-09-09

11

CD2 activation of human lamina propria lymphocytes reduces CD3 responsiveness  

PubMed Central

Lamina propria lymphocytes (LPLs) are thought to be antigen-activated memory T cells. Yet, they respond better to ligation of the CD2 receptor than the CD3 receptor by mitogenic antibodies. This study defines their constitutive state of activation and relates it to their CD3 hyporesponsiveness. The activated state of LPLs was demonstrated by their heightened display of the activated CD2 epitope, T113. Constitutive CD2 activation was shown by the reduction in spontaneous proliferation when the CD2–CD58 interaction was blocked. LPLs preferentially recognized CD58 rather than the major histocompatibility complex molecules on monocytes, triggering proliferation and interferon-? (IFN-?) secretion that was inhibited by blocking the CD2–CD58 interaction. To determine whether CD2 activation of LPLs contributes to their CD3 hyporesponsiveness, they were first stimulated with mitogenic CD2 antibodies and then tested for CD3-induced proliferation. The responses were greatly reduced by prior CD2 stimulation compared with LPLs cultured in medium alone. This effect was not caused by apoptosis or by changes in CD3 expression induced by CD2 triggering. This study shows that LPLs are constitutively activated through CD2, that they preferentially recognize CD58 on monocytes and that CD2 stimulation leads to CD3 hyporesponsiveness.

Ebert, Ellen C

2006-01-01

12

Effects of potassium channel inhibitors on nitrergic and adrenergic neurotransmission in lamina propria of the female rabbit urethra  

Microsoft Academic Search

Electrical field stimulation of strip preparations of the female rabbit urethral lamina propria induces a frequency-dependent adrenergic contraction or a non-adrenergic, non-cholinergic (NANC) relaxation, mediated by nitric oxide, depending on the prevailing tension. To study the role of potassium channels in these responses, the effects of inhibitors of voltage-dependent (dendrotoxin I, 4-aminopyridine), low (apamin) and high (iberiotoxin, charybdotoxin) conductance calcium-activated

Pia K. E. Zygmunt; Edward D. Högestätt; Karl-Erik Andersson

1996-01-01

13

Detection of pathogenic intestinal bacteria by Toll-like receptor 5 on intestinal CD11c+ lamina propria cells  

Microsoft Academic Search

Toll-like receptors (TLRs) recognize distinct microbial components and induce innate immune responses. TLR5 is triggered by bacterial flagellin. Here we generated Tlr5?\\/? 1mice and assessed TLR5 function in vivo. Unlike other TLRs, TLR5 was not expressed on conventional dendritic cells or macrophages. In contrast, TLR5 was expressed mainly on intestinal CD11c+ lamina propria cells (LPCs). CD11c+ LPCs detected pathogenic bacteria

Satoshi Uematsu; Myoung Ho Jang; Nicolas Chevrier; Zijin Guo; Yutaro Kumagai; Masahiro Yamamoto; Hiroki Kato; Nagako Sougawa; Hidenori Matsui; Hirotaka Kuwata; Hiroaki Hemmi; Cevayir Coban; Taro Kawai; Ken J Ishii; Osamu Takeuchi; Masayuki Miyasaka; Kiyoshi Takeda; Shizuo Akira

2006-01-01

14

LITAF Mediation of Increased TNF-? Secretion from Inflamed Colonic Lamina Propria Macrophages  

PubMed Central

Dysregulation of TNF-? in lamina propria macrophages (LPM) is a feature of inflammatory bowel diseases (IBD). LPS-Induced-TNF-Alpha-Factor (LITAF) is a transcription factor that mediates TNF-? expression. To determine whether LITAF participates in the mediation of TNF-? expression in acutely inflamed colonic tissues, we first established the TNBS-induced colonic inflammation model in C57BL/6 mice. LPM were harvested from non-inflamed and inflamed colonic tissue and inflammatory parameters TNF-? and LITAF mRNA and protein levels were measured ex-vivo. LPM from TNBS-treated mice secreted significantly more TNF-? at basal state and in response to LPS than LPM from untreated mice (p<0.05). LITAF mRNA and protein levels were elevated in LPM from TNBS compared with untreated animals and LPS further increased LITAF protein levels in LPM from inflamed tissue (P<0.05). To further confirm the role of LITAF in acutely inflamed colonic tissues, TNBS-induced colonic inflammation was produced in LITAF macrophage specific knockout mice (LITAF mac -/- mice) and compared to wild type (WT) C57BL/6. Twenty four hours following TNBS administration, colonic tissue from LITAF mac -/- mice had less MPO activity and reduced colonic TNF-? mRNA then WT C57BL/6 mice (p<0.05). LPM harvested from LITAF mac -/- secreted significantly less TNF-? in response to LPS than wild type (WT) C57BL/6 (p<0.05). This study provides evidence that LITAF contributes to the regulation of TNF-? in LPM harvested following acute inflammation or LPS treatment paving the way for future work focusing on LITAF inhibitors in the treatment of TNF-?-mediated inflammatory conditions.

Bushell, Kristen N.; Leeman, Susan E.; Gillespie, Earl; Gower, Adam C.; Reed, Karen L.; Stucchi, Arthur F.; Becker, James M.; Amar, Salomon

2011-01-01

15

Mucosal IL8 and TGF-  recruit blood monocytes: evidence for cross-talk between the lamina propria stroma and myeloid cells  

Microsoft Academic Search

The lamina propria of the gastrointes- tinal mucosa contains the largest population of mononuclear phagocytes in the body, yet little is known about the cellular mechanisms that regulate mononuclear cell recruitment to noninflamed and inflamed intestinal mucosa. Here, we show that intestinal macrophages do not proliferate. We also show that a substantial proportion of intestinal macrophages express chemokine receptors for

Lesley E. Smythies; Akhil Maheshwari; Ronald Clements; Devin Eckhoff; Lea Novak; Huong L. Vu; L. Meg Mosteller-Barnum; Marty Sellers; Phillip D. Smith

2006-01-01

16

Uptake and storage of vitamin A as lipid droplets in the cytoplasm of cells in the lamina propria mucosae of the rat intestine.  

PubMed

Vitamin A (retinyl palmitate) was injected subcutaneously or administered to rats by tube feeding. After subcutaneous injection, vitamin A was taken up and stored in cells of the lamina propria mucosae of the rat intestine. After oral administration, vitamin A was absorbed by the intestinal absorptive epithelial cells and transferred to cells of the lamina propria mucosae, where cells took up and stored the transferred vitamin A. The morphology of these cells was similar to that of hepatic stellate cells (also called vitamin A-storing cells, lipocytes, interstitial cells, fat-storing cells or Ito cells). Thus, these cells in the intestine could take up vitamin A from the systemic circulation and as well as by intestinal absorption, and store the vitamin in the lipid droplets in their cytoplasm. The data suggest that these cells are extrahepatic stellate cells of the digestive tract that may play roles in both the absorption and homeostasis of vitamin A. PMID:23765517

Senoo, Haruki; Mezaki, Yoshihiro; Morii, Mayako; Hebiguchi, Taku; Miura, Mitsutaka; Imai, Katsuyuki

2013-07-09

17

Redundant Role of Chemokines CCL25\\/TECK and CCL28\\/ MEC in IgA Plasmablast Recruitment to the Intestinal Lamina Propria After Rotavirus Infection1  

Microsoft Academic Search

Rotaviruses (RV) are the most important cause of severe childhood diarrheal disease. In suckling mice, infection with RV results in an increase in total and virus-specific IgA plasmablasts in the small intestinal lamina propria (LP) soon after infection, providing a unique opportunity to study the mechanism of IgA cell recruitment into the small intestine. In this study, we show that

Ningguo Feng; Marõ ´ a; C. Jaimes; Nicole H. Lazarus; Denise Monak; Caiqui Zhang; Eugene C. Butcher; Harry B. Greenberg

18

Distribution of macrophages and granulocytes expressing L1 protein (calprotectin) in human Peyer's patches compared with normal ileal lamina propria and mesenteric lymph nodes.  

PubMed Central

Antibodies to the cytosolic leucocyte L1 protein (or calprotectin) were examined for reactivity with macrophages, neutrophils, and eosinophils identified by paired immunofluorescence staining in sections of normal human ileal mucosa, including Peyer's patches. Macrophages were recognised by expression of the myelomonocytic antigen CD68 (monoclonal antibody KP1). Neutrophilic granulocytes were identified by their content of neutrophil elastase, and eosinophilic granulocytes by monoclonal antibody EG2. Virtually all CD68+ macrophages in normal lamina propria and Peyer's patches were L1- and the same was true for most extravasated macrophages in normal peripheral lymph nodes. Some mesenteric lymph nodes, however, and all peripheral lymph nodes with overt pathological processes (malignant lymphoma) contained many CD68+L1+ macrophages. Numerous L1+ cells were also localised to the crypt region and to some extent beneath the villous epithelium in normal lamina propria, but they were mainly identified as EG2+ eosinophils. Such cells were remarkably scarce or absent beneath the follicle associated epithelium in the dome region of Peyer's patches, where CD68+L1- macrophages were abundant. Also subepithelial and interfollicular CD68- interdigitating dendritic cells in Peyer's patches (recognised by antibody to S-100 protein) were usually unreactive with L1 antibody. The L1 protein shows a broad spectrum of antimicrobial activities in vitro, and its putative antiproliferative properties are interesting in relation to the immunosuppression postulated to take place in lamina propria. The virtual absence of L1 producing cells beneath the follicle associated epithelium in Peyer's patches may support the immunostimulatory function of these macrophage rich structures, which are held to be crucial for induction of specific mucosal immunity. Images Figure 1 Figure 2 Figure 3

Bjerke, K; Halstensen, T S; Jahnsen, F; Pulford, K; Brandtzaeg, P

1993-01-01

19

Nectin-4-dependent measles virus spread to the cynomolgus monkey tracheal epithelium: role of infected immune cells infiltrating the lamina propria.  

PubMed

After the contagion measles virus (MV) crosses the respiratory epithelium within myeloid cells that express the primary receptor signaling lymphocytic activation molecule (SLAM), it replicates briskly in SLAM-expressing cells in lymphatic organs. Later, the infection spreads to epithelia expressing nectin-4, an adherens junction protein expressed preferentially in the trachea, but how it gets there is not understood. To characterize the mechanisms of spread, we infected groups of 5 or 6 cynomolgus monkeys (Macaca fascicularis) with either a wild-type MV or its "N4-blind" derivative, which is unable to enter nectin-4-expressing cells because of the targeted mutation of two hemagglutinin residues. As expected, both viruses caused similar levels of immunosuppression, as monitored by reductions in white blood cell counts and lymphocyte proliferation activity. However, monkeys infected with the N4-blind MV cleared infection more rapidly. Wild-type virus-infected monkeys secreted virus, while marginal virus titers were detected in tracheal lavage fluid cells of N4-blind MV-infected hosts. Analyses of tracheal rings obtained at necropsy (day 12) documented widespread infection of individual cells or small cell clusters in the subepithelial lamina propria of monkeys infected with either virus. However, only wild-type MV spread to the epithelium, forming numerous infectious centers comprised of many contiguous columnar cells. Infected CD11c(+) myeloid (macrophage or dendritic) cells were frequently observed in the lamina propria below epithelial infectious centers. Thus, MV may use myeloid cells as vehicles not only immediately after contagion but also to infect epithelia of tissues expressing nectin-4, including the trachea. PMID:23255790

Frenzke, Marie; Sawatsky, Bevan; Wong, Xiao X; Delpeut, Sébastien; Mateo, Mathieu; Cattaneo, Roberto; von Messling, Veronika

2012-12-19

20

Nectin-4-Dependent Measles Virus Spread to the Cynomolgus Monkey Tracheal Epithelium: Role of Infected Immune Cells Infiltrating the Lamina Propria  

PubMed Central

After the contagion measles virus (MV) crosses the respiratory epithelium within myeloid cells that express the primary receptor signaling lymphocytic activation molecule (SLAM), it replicates briskly in SLAM-expressing cells in lymphatic organs. Later, the infection spreads to epithelia expressing nectin-4, an adherens junction protein expressed preferentially in the trachea, but how it gets there is not understood. To characterize the mechanisms of spread, we infected groups of 5 or 6 cynomolgus monkeys (Macaca fascicularis) with either a wild-type MV or its “N4-blind” derivative, which is unable to enter nectin-4-expressing cells because of the targeted mutation of two hemagglutinin residues. As expected, both viruses caused similar levels of immunosuppression, as monitored by reductions in white blood cell counts and lymphocyte proliferation activity. However, monkeys infected with the N4-blind MV cleared infection more rapidly. Wild-type virus-infected monkeys secreted virus, while marginal virus titers were detected in tracheal lavage fluid cells of N4-blind MV-infected hosts. Analyses of tracheal rings obtained at necropsy (day 12) documented widespread infection of individual cells or small cell clusters in the subepithelial lamina propria of monkeys infected with either virus. However, only wild-type MV spread to the epithelium, forming numerous infectious centers comprised of many contiguous columnar cells. Infected CD11c+ myeloid (macrophage or dendritic) cells were frequently observed in the lamina propria below epithelial infectious centers. Thus, MV may use myeloid cells as vehicles not only immediately after contagion but also to infect epithelia of tissues expressing nectin-4, including the trachea.

Frenzke, Marie; Sawatsky, Bevan; Wong, Xiao X.; Delpeut, Sebastien; Mateo, Mathieu; von Messling, Veronika

2013-01-01

21

The in vitro anti-inflammatory effects of recombinant anti-CD25 immunotoxin on lamina propria T cells of patients with inflammatory bowel disease are not sufficient to cure experimental colitis in mice  

Microsoft Academic Search

Background and aims: In chronic inflammatory bowel disease (IBD) such as Crohn's disease and ulcerative colitis an aberrant mucosal immune regulation is observed accompanied by upregulation of proinflammatory cytokines. Lamina propria T cells of inflamed mucosa have an activated phenotype characterized by increased expression of surface markers such as CD25. We therefore determined the anti-inflammatory effect of a recombinant immunotoxin

K. Pfister; B. M. Wittig; B. Jüngling; K. W. Ecker; S. Barth; M. Huhn; S. Sasse; A. Engert; I. Mueller-Molaian; V. Diehl; M. Zeitz; A. Stallmach

2002-01-01

22

Antigen-specific effector CD4 T lymphocytes school lamina propria dendritic cells to transfer innate tolerance.  

PubMed

Dendritic cells (DCs) have been shown to play a major role in oral tolerance, and this function has been associated with their ability to produce anti-inflammatory cytokines and to induce suppressive regulatory T cells. In this study, we demonstrate that upon oral administration of Ag, lamina propia (LP) DCs engage specific T cells and acquire a novel mechanism by which they transfer tolerance against diverse T cell specificities. Indeed, when Ig-myelin oligodendrocyte glycoprotein (MOG) carrying the MOG(35-55) epitope was orally administered into either T cell-sufficient or -deficient mice, only the T cell-sufficient hosts yielded CD8?(+) and CD8?(-) LP DCs that were able to transfer tolerance to a variety of MHC class II-restricted effector T cells. Surprisingly, these LP DCs upregulated programmed cell death ligand 1 during the initial interaction with MOG-specific T cells and used this inhibitory molecule to suppress activation of T cells regardless of Ag specificity. Furthermore, oral Ig-MOG was able to overcome experimental autoimmune encephalomyelitis induced with CNS homogenate, indicating that the DCs are able to modulate disease involving diverse T cell specificities. This previously unrecognized attribute potentiates DCs against autoimmunity. PMID:23686493

Cascio, Jason A; Haymaker, Cara L; Divekar, Rohit D; Zaghouani, Sarah; Khairallah, Marie-Therese; Wan, Xiaoxiao; Rowland, Linda M; Dhakal, Mermagya; Chen, Weirong; Zaghouani, Habib

2013-05-17

23

Impaired B cell responses to orally administered antigens in lamina propria but not Peyer's patches of G?i2-deficient mice prior to colitis  

PubMed Central

Despite numerous studies on the intestinal immune system in patients with inflammatory bowel disease (IBD) and animal models of IBD, very little is known about the immune reactivity of mucosal lymphocytes following oral immunizations under these circumstances. The reactivity of Peyer's patch (PP) and lamina propria (LP) T and B lymphocytes in inhibitory G-protein ?2 subunit-deficient (G?i2–/–) mice developing an IBD resembling ulcerative colitis was investigated following repeated oral immunizations with keyhole limpet haemocyanin (KLH), together with the adjuvant cholera toxin, prior to colitis. The antigen-specific B-cell response in the LP of both the small and the large intestines was significantly reduced in G?i2–/– as compared to wild-type mice. In contrast, the frequency of KLH-specific immunoglobulin (Ig)-producing cells in the PP did not differ between G?i2–/– and wild-type mice, whereas the total frequency of Ig-producing cells as well as the frequency of enteric flora-specific Ig-producing cells in the PP was significantly increased in G?i2–/– as compared to wild-type mice. Analysis of T cell responses following restimulation ex vivo with KLH revealed a dramatic increase in the production of interferon-? in mesenteric lymph node, PP and LP lymphocytes from G?i2-deficient as compared to wild-type mice, together with decreased production of interleukin-10 in all locations except the PP.

Ohman, Lena; Astrom, Rolf-Goran; Hornquist, Elisabeth Hultgren

2005-01-01

24

Evidence for Dendritic Cell-Dependent CD4+ T Helper-1 Type Responses to Commensal Bacteria in Normal Human Intestinal Lamina Propria  

PubMed Central

Reactivity of lamina propria (LP) T cells to commensal bacteria has been demonstrated in animal models of inflammatory bowel disease (IBD) and in humans with IBD, but few studies have evaluated the function of such cells in normal individuals. LP mononuclear cells (LPMC) were disaggregated from healthy human intestinal tissue and cultured with heat-killed commensal and pathogenic bacteria. CD3+CD4+ IFN-?-producing (Th1) cells reactive to commensal bacteria were demonstrated at frequencies ranging from 0.05 to 2.28% in LPMC. Bacteria-specific Th1 responses were inhibited by anti-HLA-DR antibodies and chloroquine exposure, were enriched in LP relative to peripheral blood, and expressed effector memory cell markers. Bacteria-specific CD4+ T cell proliferation in vitro was dependent on the presence of LP dendritic cells (DCs), which produced proinflammatory cytokines upon bacterial exposure. These results suggest that bacteria-reactive DCs and CD4+ T cells in normal LP have substantial pro-inflammatory potential that is revealed upon disaggregation in vitro.

Howe, Rawleigh; Dillon, Stephanie; Rogers, Lisa; McCarter, Martin; Kelly, Caleb; Gonzalez, Ricardo; Madinger, Nancy; Wilson, Cara C.

2009-01-01

25

Comparative analysis of basal lamina type IV collagen ? chains, matrix metalloproteinases-2 and -9 expressions in oral dysplasia and invasive carcinoma.  

PubMed

The aim of this study was to compare the expressions of basal lamina (BL) collagen IV ? chains and matrix metalloproteinases (MMP)-2 and MMP-9 in oral dysplasia (OED) and invasive carcinoma. Ten cases each of OEDs, carcinomas-in situ and oral squamous cell carcinomas (OSCCs) were examined by immunohistochemistry. Another 5 cases, each of normal and hyperplastic oral mucosa, served as controls. Results showed that ?1(IV)/?2(IV) and ?5(IV)/?6(IV) chains were intact in BLs of control and OEDs. In BLs of carcinoma-in situ, ?1(IV)/?2(IV) chains preceded ?5(IV)/?6(IV) chains in showing incipient signs of disruption. OSCCs exhibited varying degrees of collagen ?(IV) chain degradation. MMP-2 and MMP-9 were absent in controls and OED, but weakly detectable in carcinoma-in situ. In OSCC, these proteolytic enzymes were expressed in areas corresponding to collagen ?(IV) chain loss. Enzymatic activity was enhanced in higher grade OSCC, and along the tumor advancing front. Overall the present findings suggest that loss of BL collagen ?(IV) chains coincided with gain of expression for MMP-2 and MMP-9, and that these protein alterations are crucial events during progression from OED to OSCC. PMID:22694915

Tamamura, Ryo; Nagatsuka, Hitoshi; Siar, Chong Huat; Katase, Naoki; Naito, Ichiro; Sado, Yoshikazu; Nagai, Noriyuki

2012-06-12

26

Lamina propria eosinophils and mast cells in ulcerative colitis: comparison between Asians and Caucasians  

Microsoft Academic Search

To investigate the theory of hypersensitivity in the colonic mucosa of Asian patients with ulcerative colitis the rectal biopsy specimens of Asian and Caucasian patients presenting with colitis were selectively stained for both eosinophils and mast cells. Comparisons between ethnic groups were made as well as the correlation to the blood eosinophil count and two variables of active ulcerative colitis--the

G F Benfield; R Bryan; J Crocker

1990-01-01

27

Deamidation of Gliadin Peptides in Lamina Propria: Implications for Celiac Disease  

Microsoft Academic Search

Activation of small intestinal gluten-reactive CD4+ T-cells is a critical event in celiac disease. Deamidation of specific glutamine residues by tissue transglutaminase enhances\\u000a the binding of T-cell activating gliadin epitopes to DQ2, increasing T-cell recognition. Our purpose was to investigate whether\\u000a deamidated gliadin epitopes can be generated in the small intestinal mucosa by tissue transglutaminase and to characterize\\u000a the location

H. Skovbjerg; D. Anthonsen; E. Knudsen; H. Sjöström

2008-01-01

28

Infliximab treatment induces apoptosis of lamina propria T lymphocytes in Crohn's disease  

Microsoft Academic Search

Background and aims: Treatment with infliximab induces remission in about 70% of patients with steroid refractory Crohn's disease. Because Crohn's disease is considered to be mediated by uncontrolled activation of mucosal T lymphocytes, we hypothesised that infliximab could induce apoptosis of T lymphocytes.Methods: Induction of apoptosis in vivo was studied in 10 patients with therapy refractory Crohn's disease. In vitro,

T ten Hove; C van Montfrans; M. P. Peppelenbosch; S J H van Deventer

2002-01-01

29

Ontogeny of FOXP3+ Regulatory T Cells in the Postnatal Human Small Intestinal and Large Intestinal Lamina Propria  

PubMed Central

Background FOXP3+ regulatory T cells (Treg) suppress innate and adaptive immune responses and are critical for intestinal immune homeostasis. Our objective was to define the postnatal developmental regulation of Treg in relationship to other T cells in the human intestinal tract. Methods We analyzed 41 small and 18 large intestinal paraffin-embedded tissue samples from preterm and term infants with and without necrotizing enterocolitis (NEC) for presence of CD3+, CD4+, CD8+, and FOXP3+ cells by immunohistochemistry. We compared labeled cells against age, gestational age (GA), or (corrected) postmenstrual age (PMA). Results The GA ranged from 23 to 40 weeks, with a mean of 32 (SD 4.7) weeks. Independent of age, GA, or PMA, the numbers of CD4+ cells were higher in the small compared to the large intestine (p=0.046), except in patients with NEC. FOXP3+ cells could be detected as early as 23 weeks GA in both large and small bowel, and similar quantities were detected at the highest GA examined (40 weeks). We saw no statistically significant effect of GA, age, or PMA on total number of FOXP3+ cells, or by comparing FOXP3+ to CD4+ or FOXP3+to CD8+ ratios, suggesting intact ontogeny of Treg in intestinal tissue early in gestation. Conclusion Human infants exhibit presence of mucosal FOXP3+ cells in the small and large intestinal mucosa at birth and as early as 23 weeks GA. The frequency of FOXP3+ cells and the ratios of FOXP3+ to CD4+ or CD8+ cells do not change with increasing intrauterine development or postnatal age.

Weitkamp, Jorn-Hendrik; Rudzinski, Erin; Koyama, Tatsuki; Correa, Hernan; Matta, Pranathi; Alberty, Brannon; Polk, D-Brent

2010-01-01

30

Intraepithelial and lamina propria leucocyte subsets in inflammatory bowel disease: an immunohistochemical study of colon and rectal biopsy specimens.  

PubMed Central

AIMS--To gain new insights into the pathogenesis and differential diagnosis of ulcerative colitis and colonic Crohn's disease. METHODS--Immunohistochemistry for different leucocyte subsets was performed in biopsy specimens of the sigmoid colon and rectum from 55 patients with inflammatory bowel disease and 11 healthy controls. RESULTS--Colonic biopsy specimens from patients with active ulcerative colitis had significantly higher numbers of CD45+ and CD3+ leucocytes compared with those from patients with inactive disease, and higher numbers of total leucocytes and macrophages than those from patients with Crohn's disease. Rectal biopsy specimens from patients with Crohn's disease had greater numbers of intraepithelial leucocytes (CD45, CD3 and CD8 cells) than specimens from patients with active or inactive ulcerative colitis, or from healthy controls. CONCLUSIONS--Because of the phenotypic differences in the inflammatory infiltrate in the mucosa from the sigmoid colon and the rectum, the segment of the intestine to be biopsied should be specified. Assessment of the leucocytic component of the intraepithelial infiltrate in rectal biopsy specimens was more useful than examination of colonic biopsy specimens in the differential diagnosis of ulcerative colitis and Crohn's disease. Images

Caballero, T; Nogueras, F; Medina, M T; Caracuel, M D; de Sola, C; Martinez-Salmeron, F J; Rodrigo, M; Garcia del Moral, R

1995-01-01

31

Endoscopic submucosal dissection of gastric fundus subepithelial tumors originating from the muscularis propria  

PubMed Central

Endoscopic resection of gastric subepithelial tumors (SETs) carries a high risk of perforation, particularly for tumors located at the gastric fundus and originating from the muscularis propria. Based on our experience with endoscopic submucosal dissection (ESD) and a novel endoscopic device, namely the ‘Resolution clip’ for the endoscopic closure of iatrogenic upper gastrointestinal (upper GI) perforations, we evaluated the clinical feasibility and safety of ESD for gastric fundus subepithelial tumors originating from the muscularis propria. In this prospective study, 11 consecutive patients who presented with gastric SETs ?3 cm in diameter were enrolled. Regardless of whether perforation occurred, the gastric wall defect was closed with clips. The patients were followed up after the surgery. Endoscopic resection was successfully performed in 10 patients; however, in one patient a pure endoscopic approach was impossible as the lesion was severely adhered to surrounding tissue, and a switch to laparoscopic wedge resection was necessary. The mean resected tumor size was 18.8×17.2 mm and the mean surgery time of the 10 patients with ESD was 81 min (range 45–130 min). Histological diagnosis was gastrointestinal stromal tumor (GIST) in eight lesions [very low risk according to the National Institutes of Health (NIH) risk classification] and leiomyoma in three lesions. Perforation occurred in 3/10 patients. Gastric closure with the Resolution clips was performed successfully in all cases. Early post-ESD bleeding (EPEB) occurred in one patient. Basic ferric sulfate solution was sprayed during the upper GI endoscopy examination and the bleeding stopped. No complications occurred and the follow-up was unremarkable. In this early study, ESD using the Resolution clip was demonstrated to be a feasible and minimally invasive treatment for gastric fundus subepithelial tumors originating from the muscularis propria.

LI, LEI; WANG, FENG; WU, BO; WANG, QINGCAI; WANG, CHANGHUI; LIU, JIYONG

2013-01-01

32

Studies of immunity and bacterial invasiveness in mice given a recombinant salmonella vector encoding murine interleukin-6.  

PubMed Central

Interleukin-6 (IL-6) was expressed in Salmonella typhimurium in an attempt to increase the mucosal immune response against the bacterium. Murine IL-6 was PCR amplified from cDNA, cloned, sequenced, and found to be functionally active when expressed in S. typhimurium BRD509, the (delta)aroA (delta)aroD vaccine strain. Expression of murine IL-6 did not appear to adversely affect the growth of salmonellae, as the construct was retained in the absence of antibiotic selection and the growth rate was unaffected compared with that of the parent strain in vitro. However, IL-6 expression led to a significant reduction in bacterial invasiveness in vitro and in vivo. Splenocytes and small intestinal lamina propria lymphocytes were isolated from mice orally immunized with BRD509 expressing IL-6 (pKK233-2/IL-6), and the number of antibody-secreting cells was determined by the ELISPOT technique. No differences were observed between mice immunized with BRD509(pKK.233-2/IL-6) and those immunized with BRD509(pKK233-2) with respect to the antibody subclass-specific responses elicited despite the markedly reduced invasiveness of the former. Serum antibody responses were also examined by a kinetic enzyme-linked immunosorbent assay (ELISA), and equivalent levels of antibody response were detected in mice given BRD509(pKK233-2/IL-6) and those given BRD509(pKK233-2). The humoral immune response against bacterial lipopolysaccharides was also examined in transgenic IL-6-deficient mice given oral inocula of BRD509. Equivalent numbers of antibody-secreting cells (ELISPOTs) were observed in the spleens and laminae propriae of both IL-6-deficient (-/-) mice and control (+/+) mice harboring an intact IL-6 gene, whereas small, yet significant differences in the serum immunoglobulin A ELISA titers were observed. These data suggest that the immunoglobulin A response against Salmonella lipopolysaccharides is largely IL-6 independent.

Dunstan, S J; Ramsay, A J; Strugnell, R A

1996-01-01

33

Mast cells expressing interleukin 17 in the muscularis propria predict a favorable prognosis in esophageal squamous cell carcinoma.  

PubMed

The proinflammatory cytokine interleukin 17 (IL-17) is considered to play a crucial role in diverse human tumors; however, its role in disease progression remains controversial. This study investigated the cellular source and distribution of IL-17 in esophageal squamous cell carcinoma (ESCC) in situ and determined its prognostic value. Immunohistochemistry, immunofluorescence and immunoelectron microscopy were used to identify IL-17-expressing cells in ESCC tissues, paying particular attention to their anatomic localization. Kaplan-Meier analysis and Cox proportional hazards regression models were applied to estimate overall survival in 215 ESCC patients with long-term follow-up (>10 years). The results showed that mast cells, but not T cells or macrophages, were the predominant cell type expressing IL-17 in ESCC tissues. Unexpectedly, these IL-17(+) cells were highly enriched in the muscularis propria rather than the corresponding tumor nest (p < 0.0001). The density of IL-17(+) cells in muscularis propria was inversely associated with tumor invasion (p = 0.016) and served as an independent predictor of favorable survival (p = 0.007). Moreover, the levels of IL-17(+) cells in muscularis propria were positively associated with the density of effector CD8(+) T cells and activated macrophages in the same area (both p < 0.0001). This finding suggested that mast cells may play a significant role in tumor immunity by releasing IL-17 at a previously unappreciated location, the muscularis propria, in ESCC tissues, which could serve as a potential prognostic marker and a novel therapeutic target for ESCC. PMID:23912243

Wang, Bo; Li, Lian; Liao, Yuan; Li, Jinqing; Yu, Xingjuan; Zhang, Yi; Xu, Jing; Rao, Huilan; Chen, Shupeng; Zhang, Lanjun; Zheng, Limin

2013-08-03

34

Muscular architecture in the omasal laminae of cattle and sheep  

Microsoft Academic Search

The muscular architecture of the bovine omasal laminae was examined. The omasal laminae had three thin smooth muscle layers which consisted of an intermediate layer and two lateral layers. The muscle bundles of the intermediate layers ran radially in the laminae and those of the two lateral layers ran parallel to the free border of the laminae. At the free

Y. Yamamoto; N. Kitamura; J. Yamada; T. Yamashita

1991-01-01

35

Herpes Simplex Virus Type 1 Infection Facilitates Invasion of Staphylococcus aureus into the Nasal Mucosa and Nasal Polyp Tissue  

PubMed Central

Background Staphylococcus aureus (S. aureus) plays an important role in the pathogenesis of severe chronic airway disease, such as nasal polyps. However the mechanisms underlying the initiation of damage and/or invasion of the nasal mucosa by S. aureus are not clearly understood. The aim of this study was to investigate the interaction between S. aureus and herpes simplex virus type 1 (HSV1) in the invasion of the nasal mucosa and nasal polyp tissue. Methodology/Principal Findings Inferior turbinate and nasal polyp samples were cultured and infected with either HSV1 alone, S. aureus alone or a combination of both. Both in turbinate mucosa and nasal polyp tissue, HSV1, with or without S. aureus incubation, led to focal infection of outer epithelial cells within 48 h, and loss or damage of the epithelium and invasion of HSV1 into the lamina propria within 72 h. After pre-infection with HSV1 for 24 h or 48 h, S. aureus was able to pass the basement membrane and invade the mucosa. Epithelial damage scores were significantly higher for HSV1 and S. aureus co-infected explants compared with control explants or S. aureus only-infected explants, and significantly correlated with HSV1-invasion scores. The epithelial damage scores of nasal polyp tissues were significantly higher than those of inferior turbinate tissues upon HSV1 infection. Consequently, invasion scores of HSV1 of nasal polyp tissues were significantly higher than those of inferior turbinate mucosa in the HSV1 and co-infection groups, and invasion scores of S. aureus of nasal polyp tissues were significantly higher than those of inferior turbinate tissues in the co-infection group. Conclusions/Significance HSV1 may lead to a significant damage of the nasal epithelium and consequently may facilitate invasion of S. aureus into the nasal mucosa. Nasal polyp tissue is more susceptible to the invasion of HSV1 and epithelial damage by HSV1 compared with inferior turbinate mucosa.

Holtappels, Gabriele; Vaneechoutte, Mario; Krysko, Olga; Zhang, Luo; Han, Demin; Nauwynck, Hans J.; Bachert, Claus

2012-01-01

36

A new in vivo model for studying invasion and metastasis of rat and human bladder carcinomas.  

PubMed

The biological potential of tumor cells is best evaluated at the organ site orthotopic to the tumor cells. Recent studies have documented site-specific differences in the potential of tumor cell growth. However, orthotopic implantation of bladder cancer cells into bladders of nude mice only resulted in a low tumor yield. We have developed a new model that consists of a rat bladder transplanted into the retroperitoneal space and connected to a reservoir s.c. placed in a nude mouse. Rat malignant bladder cancer cells (MYU3L and LMC19) transfected with the human growth hormone (hGH) gene as a biomarker were introduced into the transplanted bladder by percutaneous puncture of the attached reservoir. Successful uptake was indicated by a progressive rise in the hGH level in the bladder aspirate. When examined at 6-16 weeks post transplantation, all mice that had received MYU3L (n = 6) or LMC19 (n = 6) cells were found to have invasive carcinomas. MYU3L was highly invasive, forming multiple peritoneal implants, but was not metastatic. LMC19 was deeply invasive and metastasized to the retroperitoneal and subclavian lymph nodes and the lungs (4/6). Of two human bladder cancer cell lines (RT4 and T24) tested, RT4 formed multiple minute papillary tumors in five of six bladders, two of which were minimally invasive to the muscle layer. T24 cells formed only one to two small tumors in three of six bladders, and these were confined to the lamina propria. This system appears promising for studies of the mechanism of tumor invasion and metastasis and for evaluation of antineoplastic agents. PMID:8353837

Kameyama, S; Kawamata, H; Kawai, K; Oyasu, R

1993-08-01

37

[Endoscopic characteristics of upper gastrointestinal mesenchymal tumors originating from muscularis mucosa or muscularis propria].  

PubMed

Background/Aims: Subepithelial tumors are occasionally found during upper gastrointestinal endoscopy. The purpose of this study was to evaluate endoscopic characteristics of mesenchymal tumors originating from muscularis mucosa or muscularis propria.Methods: A total of 307 mesenchymal tumors of the upper gastrointestinal tract were diagnosed between March 2006 and February 2012 at Yeouido St. Mary's Hospital (Seoul, Korea). Data on endoscopic and endoscopic ultrasonographic findings were collected and analyzed by retrospectively reviewing the medical records.Results: The mean size of the mesenchymal tumors originating from muscularis mucosa was significantly smaller than those originating from muscularis propria (10.5±6.9 mm vs. 14.3±13.9 mm, p=0.035). The most common locations of the mesenchymal tumors originating from muscularis mucosa and muscularis propria were esophagus (69.1%) and body of the stomach (43.3%), respectively (p<0.001). Rolling sign was more commonly observed with mesenchymal tumors originating from muscularis mucosa (80.4%, p=0.001), and cushion sign was more frequently absent with those originating from muscularis propria (72.4%, p<0.001). Internal echo was homogenous in 89.7% and 81.9% of mesenchymal tumors originating from muscularis mucosa and muscularis propria, respectively (p=0.092).Conclusions: The size, location, and movability of mesenchymal tumors originating from muscularis mucosa were different from those of mesenchymal tumor originating from muscularis propria.propria. (Korean J Gastroenterol 2013;62:92-96). PMID:23981942

Song, Jun Ho; Kim, Jin Il; Kim, Hyun Jin; Cho, Hyung Jun; Kim, Hye Kang; Cheung, Dae Young; Park, Soo Hern; Kim, Jae Kwang

2013-08-25

38

Signaling via LT?R on the lamina propria stromal cells of the gut is required for IgA production  

Microsoft Academic Search

Peyer's patches (PPs) and\\/or mesenteric lymph nodes (MLNs) are thought to be essential for immunoglobulin A (IgA) production. We found that the severe IgA deficiency in lymphotoxin-deficient (LT?\\/?) mice could be fully reversed by reconstitution with LT-expressing bone marrow, despite the absence of both LNs and PPs. The number of IgA precursors from LT?\\/? mice was not reduced, and they

Hyung-Sik Kang; Robert K. Chin; Yang Wang; Ping Yu; Jun Wang; Kenneth A. Newell; Yang-Xin Fu

2002-01-01

39

Distribution of macrophages and granulocytes expressing L1 protein (calprotectin) in human Peyer's patches compared with normal ileal lamina propria and mesenteric lymph nodes  

Microsoft Academic Search

Antibodies to the cytosolic leucocyte L1 protein (or calprotectin) were examined for reactivity with macrophages, neutrophils, and eosinophils identified by paired immunofluorescence staining in sections of normal human ileal mucosa, including Peyer's patches. Macrophages were recognised by expression of the myelomonocytic antigen CD68 (monoclonal antibody KP1). Neutrophilic granulocytes were identified by their content of neutrophil elastase, and eosinophilic granulocytes by

K Bjerke; T S Halstensen; F Jahnsen; K Pulford; P Brandtzaeg

1993-01-01

40

Basal Lamina Components in Experimentally Induced Skin Blisters  

Microsoft Academic Search

The distribution of basement membrane glycoproteins, fibronectin, laminin, and type IV collagen was studied in experimentally induced skin blisters in which the epidermis is separated from the dermis through the lamina lucida part of basal lamina. Fibronectin was found surrounding the blister cavity and in a primary covering formed on the bottom of the blister. Neither laminin nor type IV

Olli Saksela; Kari Alitalo; Urpo Kiistala; Antti Vaheri

1981-01-01

41

Nuclear lamina at the crossroads of the cytoplasm and nucleus  

PubMed Central

The nuclear lamina is a protein meshwork that lines the nuclear envelope in metazoan cells. It is composed largely of a polymeric assembly of lamins, which comprise a distinct sequence homology class of the intermediate filament protein family. On the basis of its structural properties, the lamina originally was proposed to provide scaffolding for the nuclear envelope and to promote anchoring of chromatin and nuclear pore complexes at the nuclear surface. This viewpoint has expanded greatly during the past 25 years, with a host of surprising new insights on lamina structure, molecular composition and functional attributes. It has been established that the self-assembly properties of lamins are very similar to those of cytoplasmic intermediate filament proteins, and that the lamin polymer is physically associated with components of the cytoplasmic cytoskeleton and with a multitude of chromatin and inner nuclear membrane proteins. Cumulative evidence points to an important role for the lamina in regulating signaling and gene activity, and in mechanically coupling the cytoplasmic cytoskeleton to the nucleus. The significance of the lamina has been vaulted to the forefront by the discovery that mutations in lamins and lamina-associated polypeptides lead to an array of human diseases. A key future challenge is to understand how the lamina integrates pathways for mechanics and signaling at the molecular level. Understanding the structure of the lamina from the atomic to supramolecular levels will be essential for achieving this goal.

Huber, Michael D.

2012-01-01

42

Reorganization of the nuclear lamina and cytoskeleton in adipogenesis  

Microsoft Academic Search

A thorough understanding of fat cell biology is necessary to counter the epidemic of obesity. Although molecular pathways\\u000a governing adipogenesis are well delineated, the structure of the nuclear lamina and nuclear-cytoskeleton junction in this\\u000a process are not. The identification of the ‘linker of nucleus and cytoskeleton’ (LINC) complex made us consider a role for\\u000a the nuclear lamina in adipose conversion.

Valerie L. R. M. Verstraeten; Johan Renes; Frans C. S. Ramaekers; Miriam Kamps; Helma J. Kuijpers; Fons Verheyen; Martin Wabitsch; Peter M. Steijlen; Maurice A. M. van Steensel; Jos L. V. Broers

2011-01-01

43

Neurons innervating the lamina in the butterfly, Papilio xuthus.  

PubMed

The butterfly Papilio xuthus has compound eyes with three types of ommatidia. Each type houses nine spectrally heterogeneous photoreceptors (R1-R9) that are divided into six spectral classes: ultraviolet, violet, blue, green, red, and broad-band. Analysis of color discrimination has shown that P. xuthus uses the ultraviolet, blue, green, and red receptors for foraging. The ultraviolet and blue receptors are long visual fibers terminating in the medulla, whereas the green and red receptors are short visual fibers terminating in the lamina. This suggests that processing of wavelength information begins in the lamina in P. xuthus, unlike in flies. To establish the anatomical basis of color discrimination mechanisms, we examined neurons innervating the lamina by injecting Neurobiotin into this neuropil. We found that in addition to photoreceptors and lamina monopolar cells, three distinct groups of cells project fibers into the lamina. Their cell bodies are located (1) at the anterior rim of the medulla, (2) between the proximal surface of the medulla and lobula plate, and (3) in the medulla cell body rind. Neurobiotin injection also labeled distinct terminals in medulla layers 1, 2, 3, 4 and 5. Terminals in layer 4 belong to the long visual fibers (R1, 2 and 9), while arbors in layers 1, 2 and 3 probably correspond to terminals of three subtypes of lamina monopolar cells, respectively. Immunocytochemistry coupled with Neurobiotin injection revealed their transmitter candidates; neurons in (1) and a subset of neurons in (2) are immunoreactive to anti-serotonin and anti-?-aminobutyric acid, respectively. PMID:23407865

Hamanaka, Yoshitaka; Shibasaki, Hiromichi; Kinoshita, Michiyo; Arikawa, Kentaro

2013-02-14

44

Fine structure of the lamina basilaris of guinea pig cochlea.  

PubMed

The lamina basilaris of guinea pig cochlea was studied with SEM after trypsin treatment, and with TEM of resin sections and deep-etching replicas. The lamina consists of radial, evenly compacted filaments in the zona arcuata, and radial, discretely bundled filaments in the zona pectinata. In both zones, elementary filaments measured about 12 nm in thickness on the replica. The filaments formed more or less irregular passing bridges with each other and, eventually, a three-dimensional network which was continuous with the basement membrane under the supporting cells. PMID:8291428

Katori, Y; Hozawa, K; Kikuchi, T; Tonosaki, A; Takasaka, T

1993-11-01

45

The functional organization of the crayfish lamina ganglionaris  

Microsoft Academic Search

1.The functional properties of the multicolumnar interneurons of the crayfish lamina ganglionaris were examined by intracellular recording and the cell structures were revealed with the aid of Lucifer yellow or horseradish peroxidase iontophoresis.2.The multicolumnar monopolar cell M5 (Fig. 1) responds to a light pulse with a depolarizing compound EPSP and a burst of action potentials. Both the EPSP amplitude and

Lolin T. Wang-Bennett; Raymon M. Glantz

1987-01-01

46

Globular and asymmetric acetylcholinesterase in frog muscle basal lamina sheaths  

Microsoft Academic Search

After denervation in vivo, the frog cutaneus pectoris muscle can be led to degenerate by sectioning the muscle fibers on both sides of the region rich in motor endplate, leaving, 2 wk later, a muscle bridge containing the basal lamina (BL) sheaths of the mus- cle fibers (28). This preparation still contains various tissue remnants and some acetylcholine receptor-con- taining

Marc Nicolet; Martine Pingon-Raymond; Frangois Rieger

1986-01-01

47

Substructure in an Epithelial Basal Lamina (Basement Membrane).  

National Technical Information Service (NTIS)

A well ordered grid structure is described in the basal lamina of the Aedes aegypti midgut epithelium. In sections parallel to the epithelial base, the grid structure is a series of dense lines intersecting at approximately right angles to one another. Th...

J. A. Terzakis

1967-01-01

48

A simple mechanical method to isolate the basal lamina of insect midgut epithelial cells.  

PubMed

In mealworms (Tenebrio molitor) the midgut epithelium is surrounded by a 1.6microm thick basal lamina of low electron density with a framework of high electron density imbedded in a part of it. The lamina can be isolated by ultrasonication followed by repeated filtrations and high-speed centrifugations, making large-scale preparation of the lamina for further analyses possible. The isolation of the basal lamina is confirmed by electron microscopy. PMID:18620148

Koefoed, B M

1985-01-01

49

Fos induction in lamina I projection neurons in response to noxious thermal stimuli  

Microsoft Academic Search

Lamina I of the spinal cord contains many projection neurons: the majority of these are activated by noxious stimulation, although some respond to other stimuli, such as innocuous cooling. In the rat, approximately 80% of lamina I projection neurons express the neurokinin 1 (NK1) receptor, on which substance P acts. Lamina I neurons can be classified into three main morphological

A. J. Todd; R. C. Spike; S. Young; Z. Puskár

2005-01-01

50

Single-cell dynamics of genome-nuclear lamina interactions.  

PubMed

The nuclear lamina (NL) interacts with hundreds of large genomic regions termed lamina associated domains (LADs). The dynamics of these interactions and the relation to epigenetic modifications are poorly understood. We visualized the fate of LADs in single cells using a "molecular contact memory" approach. In each nucleus, only ~30% of LADs are positioned at the periphery; these LADs are in intermittent molecular contact with the NL but remain constrained to the periphery. Upon mitosis, LAD positioning is not detectably inherited but instead is stochastically reshuffled. Contact of individual LADs with the NL is linked to transcriptional repression and H3K9 dimethylation in single cells. Furthermore, we identify the H3K9 methyltransferase G9a as a regulator of NL contacts. Collectively, these results highlight principles of the dynamic spatial architecture of chromosomes in relation to gene regulation. PMID:23523135

Kind, Jop; Pagie, Ludo; Ortabozkoyun, Havva; Boyle, Shelagh; de Vries, Sandra S; Janssen, Hans; Amendola, Mario; Nolen, Leisha D; Bickmore, Wendy A; van Steensel, Bas

2013-03-21

51

Dynamics of LaminA Processing Following Precursor Accumulation  

Microsoft Academic Search

Lamin A (LaA) is a component of the nuclear lamina, an intermediate filament meshwork that underlies the inner nuclear membrane (INM) of the nuclear envelope (NE). Newly synthesized prelamin A (PreA) undergoes extensive processing involving C-terminal farnesylation followed by proteolysis yielding non-farnesylated mature lamin A. Different inhibitors of these processing events are currently used therapeutically. Hutchinson-Gilford Progeria Syndrome (HGPS) is

Qian Liu; Dae In Kim; Janet Syme; Phyllis Luvalle; Brian Burke; Kyle J. Roux; Peter Sommer

2010-01-01

52

Elastic and viscoelastic characterization of transversely isotropic composite laminae  

NASA Astrophysics Data System (ADS)

With the advent of "designed damping" in composite materials, and modern computer design tools, accurate three-dimensional material properties information is critically important. Further, design of advanced composite structures often requires knowledge of material properties over a range of temperatures. Conventional testing approaches for the determination of material properties present difficulties related to specimen preparation, fixturing and test apparatus. Consequently, engineers frequently make use of micromechanics generated properties. Unfortunately, micromechanics approaches do not usually account for manufacturing and temperature variations, which affect material properties. This research focuses on developing approaches to allow experimental characterization of elastic and viscoelastic properties of fiber reinforced composite laminae, over a range of temperatures. In addition to investigating the temperature dependence of the three-dimensional material properties, for the viscoelastic characterization, the effect of loading frequency is also addressed. A technique for the determination of the three-dimensional elastic coefficients of transversely isotropic laminae is developed, using a combination of laminate coefficient of thermal expansion (CTE) measurements and two elastic properties measured from a standard tensile test. The CTE measurements are conducted in a laboratory thermo mechanical analyzer (TMA), using samples of simple geometry. PEEK/IM7 laminae are used to verify this approach and the computed room temperature elastic properties are in good agreement with quoted elastic material properties measured by standard techniques. Viscoelastic material characterization is essential to designs that incorporate specified levels of damping, and to understand processing problems. This work also presents an approach to determine the three-dimensional viscoelastic properties of transversely isotropic fiber reinforced materials. The minimum number of independent coefficients for three-dimensional viscoelastic characterization of transversely isotropic laminae is investigated and a reduced set of material coefficients, that specify the constitutive relationships, is proposed. The experimental approach developed is based only on flexural measurements allowing complete characterization using a dynamic mechanical analyzer (DMA). To verify the approach, viscoelastic properties of PEEK/IM7 laminae and laminates are determined over ranges of temperature and frequency. The mechanics relations and experimental techniques developed in this work provide means for measuring the elastic and viscoelastic properties of fiber reinforced composites, and constitute a valuable contribution to the understanding of temperature and frequency dependence of these mechanical properties.

Melo, Jose Daniel Diniz

53

Nuclear lamin-A scales with tissue stiffness and enhances matrix-directed differentiation.  

PubMed

Tissues can be soft like fat, which bears little stress, or stiff like bone, which sustains high stress, but whether there is a systematic relationship between tissue mechanics and differentiation is unknown. Here, proteomics analyses revealed that levels of the nucleoskeletal protein lamin-A scaled with tissue elasticity, E, as did levels of collagens in the extracellular matrix that determine E. Stem cell differentiation into fat on soft matrix was enhanced by low lamin-A levels, whereas differentiation into bone on stiff matrix was enhanced by high lamin-A levels. Matrix stiffness directly influenced lamin-A protein levels, and, although lamin-A transcription was regulated by the vitamin A/retinoic acid (RA) pathway with broad roles in development, nuclear entry of RA receptors was modulated by lamin-A protein. Tissue stiffness and stress thus increase lamin-A levels, which stabilize the nucleus while also contributing to lineage determination. PMID:23990565

Swift, Joe; Ivanovska, Irena L; Buxboim, Amnon; Harada, Takamasa; Dingal, P C Dave P; Pinter, Joel; Pajerowski, J David; Spinler, Kyle R; Shin, Jae-Won; Tewari, Manorama; Rehfeldt, Florian; Speicher, David W; Discher, Dennis E

2013-08-30

54

The basement membranes of cryofixed or aldehyde-fixed, freeze-substituted tissues are composed of a lamina densa and do not contain a lamina lucida.  

PubMed

When tissues are processed for electron microscopy by conventional methods, such as glutaraldehyde fixation followed by rapid dehydration in acetone, basement membranes show two main layers: the electron-lucent "lamina lucida". (or rara) and the electron-dense "lamina densa". In an attempt to determine whether this subdivision is real or artefactual, two approaches have been used. Firstly, rat and mouse seminiferous tubules, mouse epididymis and associated tissues, and anterior parts of mouse eyes were subjected to cryofixation by instant freezing followed by freeze substitution in a -80 degrees C solution of osmium tetroxide in dry acetone, which was gradually warmed to room temperature over a 3-day period. The results indicate that, in areas devoid of ice crystals, basement membranes consist of a lamina densa in direct contact with the plasmalemma of the associated cells without an intervening lamina lucida. Secondly, a series of tissues from mice perfused with 3% glutaraldehyde were cryoprotected in 30% glycerol, frozen in Freon 22 and subjected to a 3-day freeze substitution in osmium tetroxide-acetone as above. Under these conditions, no lamina lucida accompanies the lamina densa in the basement membranes of the majority of tissues, including kidney, thyroid gland, smooth and skeletal muscle, ciliary body, seminiferous tubules, epididymis and capillary endothelium. Thus, even though these tissues have been fixed in glutaraldehyde, no lamina lucida appears when they are slowly dehydrated by freeze substitution. It is concluded that the occurrence of this lamina in conventionally processed tissues is not due to fixation but to the rapid dehydration. However, in this series of experiments, the basement membranes of trachea and plantar epidermis include a lamina lucida along their entire length, while those of esophagus and vas deferens may or may not include a lamina lucida. To find out if the lamina lucida appearing under these conditions is a real structure or an artefact, the trachea and epidermis were fixed in paraformaldehyde and slowly dehydrated by freeze substitution. Under these conditions, no lamina lucida was found. Since this result is the same as observed in other tissues by the previous approaches, it is proposed that the lamina lucida is an artefact in these as in the other investigated basement membranes. Thus, basement membranes are simply composed of a lamina densa that closely follows the plasmalemma of the associated cells.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:8364960

Chan, F L; Inoue, S; Leblond, C P

1993-07-01

55

Extracting paleoclimate signals from sediment laminae: An automated 2-D image processing method  

NASA Astrophysics Data System (ADS)

Lake sediments commonly contain laminations and the occurrence and quantitative attributes of these microstrata contain signals of their depositional environment, limnological conditions, and past climate. However, the identification and measurement of laminae and their attributes remains a largely semi-manual process that is tedious, labor intensive, but subject to human error. Here, we present a method to automatically measure and accurately extract lamina properties from sediment core images. This method is comprised of four major components: (1) image enhancement that includes noise reduction and contrast enhancement to improve signal-to-background ratio and resolution of laminae; (2) identification of 1-D laminae for a user-chosen area in an image; (3) laminae connectivity analyses on the 1-D laminae to obtain a lamina stratigraphy; and (4) extraction and retrieval of the primary and derived lamination stratigraphic data. Sediment core images from Lake Hitchcock and Lake Bosumtwi were used for algorithm development and testing. Our experiments show a complete match between laminae produced by the software and manual process for images from Lake Hitchcock. Quantitative comparisons reveal an insignificant discrepancy in the number of laminae identified automatically by the software and manually by researchers, and in over 90% of the cases the position mismatch of individual laminae is less than one pixel between the software and the manual method for the experimental images from Lake Bosumtwi.

Gan, Stoney Q.; Scholz, Christopher A.

2013-03-01

56

Caenorhabditis elegans as a model system for studying the nuclear lamina and laminopathic diseases.  

PubMed

The nuclear lamina is a protein-rich network located directly underneath the inner nuclear membrane of metazoan nuclei. The components of the nuclear lamina have been implicated in nearly all nuclear functions; therefore, understanding the structural, mechanical, and signal transducing properties of these proteins is crucial. In addition, mutations in many of these proteins cause a wide range of human diseases, the laminopathies. The structure, function, and interaction of the lamina proteins are conserved among metazoans, emphasizing their fundamental roles in the nucleus. Several of the advances in the field of the nuclear lamina have come from studies performed in Caenorhabditis elegans or on C. elegans proteins expressed in vitro. Here, we discuss the current knowledge about the nuclear lamina, including an overview of the technical tools offered by C. elegans that make it a powerful model organism for the study of the nuclear lamina and laminopathic diseases. PMID:21970988

Bank, Erin M; Gruenbaum, Yosef

2011-09-01

57

Ultrahigh-resolution Spectral Domain Optical Coherence Tomography Imaging of the Lamina Cribrosa  

PubMed Central

Study of the structure of the lamina cribrosa is critical in glaucoma research. The purpose of this study is to determine the optimal spectral domain optical coherence tomography imaging protocol for the digital isolation and display of the lamina cribrosa. Three-dimensional datasets centered on the lamina cribrosa were obtained with 200 × 200 to 512 × 512 A-scan densities. The effect of scan density and c-mode slab thickness was subjectively compared. Increasing slab thickness reduced the sharpness of visible prelamina and lamina cribrosa structures. In retrolamina structures, thin slabs provided good visualization, but increased slab size increased the visibility of deeper structures. Scan times as short as 2.3 seconds (256 × 256 A-scans) degraded visualization of the shape of the optic nerve head. The optical scan protocol for lamina cribrosa imaging appears to be a 3 × 3 mm 200 × 200 A-scan volume with the lamina cribrosa positioned near direct current.

Kagemann, Larry; Ishikawa, Hiroshi; Wollstein, Gadi; Brennen, Peter M.; Townsend, Kelly A.; Gabriele, Michelle L.; Schuman, Joel S.

2010-01-01

58

Biointegration of the Osteo-odonto Lamina in the Modified Osteo-odonto Keratoprosthesis: Engineering of Tissue to Restore Lost Vision.  

PubMed

The modified osteo-odonto keratoprosthesis (MOOKP) is a biologic keratoprosthesis that is used to treat a severely scarred cornea. The procedure involves multiple stages, including the transplantation of buccal mucosa to the damaged ocular surface and the implantation of an osteo-odonto lamina with a mounted polymethylmethacrylate lens. Among the keratoprostheses currently available, the MOOKP has proven to be the most effective based on the number of patients who have undergone the procedure and the duration of documented follow-up. Upon successful biointegration of the osteo-odonto lamina, the keratoprosthesis is able to resist resorption, provide stability, and prevent bacterial invasion and epithelial ingrowth. The effectiveness of the MOOKP is dependent on the anatomic and physiologic characteristics of the dental tissues and periodontal ligament. PMID:24066348

Sawatari, Yoh; Marx, Robert E; Perez, Victor L; Parel, Jean-Marie

59

Distinct antinociceptive actions mediated by different opioid receptors in the region of lamina I and laminae III-V of the dorsal horn of the rat.  

PubMed Central

1. In view of the presence of mu, delta and kappa opioid receptors in the spinal dorsal horn and their apparent involvement in behavioural analgesia, the present experiments addressed the action of selective agonists ionophoresed in the vicinity of rat dorsal horn neurones which were located either in lamina I or in laminae III-V. 2. In laminae III-V, kappa agonists (U50488H and dynorphin A) caused a selective inhibition of the nociceptive responses of multireceptive cells, whilst mu and delta agonists [( D-Ala2, MePhe4, Gly-ol]enkephalin and [D-Pen2, D-Pen5]enkephalin respectively) failed to alter either the spontaneous activity or the response to noxious and innocuous cutaneous stimuli and to D,L-homocysteic acid or glutamate. Nocispecific neurones were encountered too rarely in laminae III-V to study their properties. 3. In lamina I, agonists had no effects on either nocispecific or multireceptive neurones. In contrast, the mu agonist [D-Ala2, MePhe4, Gly-ol]enkephalin consistently inhibited nociceptive responses of both multireceptive and nocispecific lamina I cells. The delta agonist [D-Pen2, D-Pen5]enkephalin consistently caused selective inhibition of the nociceptive responses of multireceptive cells but had a mixed profile of action on nocispecific cells. 4. These results suggest that mu, delta and kappa opioid receptors mediate different antinociceptive actions in both laminae III-V and lamina I. The study reveals a distinct physiological role for delta receptors in modulating nociceptive inputs to lamina I neurones. In contrast to mu and kappa receptor actions, delta receptors heterogeneously influence subpopulations of neurones.

Hope, P. J.; Fleetwood-Walker, S. M.; Mitchell, R.

1990-01-01

60

Basal lamina formation on thyroid epithelia in separated follicles in suspension culture  

PubMed Central

When thyroid follicles are isolated by collagenase treatment of minced thyroid lobes, the basal lamina around each follicle is removed. The basal lamina does not reform when follicles are cultured in suspension in Coon's modified Ham's F-12 medium containing, in addition, 0.5% calf serum, insulin, transferrin, and thyrotropin. We have added acid soluble collagen and/or laminin to see if they would result in the formation of a basal lamina. An extended basal lamina did not form when follicles were embedded in a gel formed from acid-soluble rat tendon collagen or from calf skin collagen when added at a concentration of 100 micrograms collagen/ml. However, laminin at a concentration of 5.1 micrograms/ml gave rise to short segments of a basal lamina within 30 min. At longer time intervals, the segments lengthened and covered the base of many cells, and were continuous across the gap between cells and across the mouth of a coated pit. Not all basal surfaces were covered, and no exposed apical surfaces with microvilli had a basal lamina. There was no obvious difference in the appearance of the basal lamina if collagen was added in addition to laminin, but collagen, in contact with the plasma membrane when added alone, was lifted off the membrane in the presence of the basal lamina. The basal lamina appeared denser if formed in the presence of 5% serum instead of 0.5%.

1982-01-01

61

Robust nuclear lamina-based cell classification of aging and senescent cells  

PubMed Central

Changes in the shape of the nuclear lamina are exhibited in senescent cells, as well as in cells expressing mutations in lamina genes. To identify cells with defects in the nuclear lamina we developed an imaging method that quantifies the intensity and curvature of the nuclear lamina. We show that this method accurately describes changes in the nuclear lamina. Spatial changes in nuclear lamina coincide with redistribution of lamin A proteins and local reduction in protein mobility in senescent cell. We suggest that local accumulation of lamin A in the nuclear envelope leads to bending of the structure. A quantitative distinction of the nuclear lamina shape in cell populations was found between fresh and senescent cells, and between primary myoblasts from young and old donors. Moreover, with this method mutations in lamina genes were significantly distinct from cells with wild-type genes. We suggest that this method can be applied to identify abnormal cells during aging, in in vitro propagation, and in lamina disorders.

Righolt, Christiaan H.; van 't Hoff, Merel L.R.; Vermolen, Bart J.; Young, Ian T.; Raz, Vered

2011-01-01

62

Investigating Invasives  

ERIC Educational Resources Information Center

|Invasive species, commonly known as "invasives," are nonnative plants, animals, and microbes that completely take over and change an established ecosystem. The consequences of invasives' spread are significant. In fact, many of the species that appear on the Endangered Species list are threatened by invasives. Therefore, the topic of invasive

Lightbody, Mary

2008-01-01

63

A Study of Ozone Laminae Using Diabatic Trajectories, Contour Advection and Photochemical Trajectory Model Simulations  

Microsoft Academic Search

In this paper, we show that the rate of ozone loss in both polar and mid-latitudes, derived from ozonesonde and satellite data, has almost the same vertical distribution (although opposite sense) to that of ozone laminae abundance. Ozone laminae appear in the lower stratosphere soon after the polar vortex is established in autumn, increase in number throughout the winter and

S. J. Reid; M. Rex; P. Von Der Gathen; I. Fløisand; F. Stordal; G. D. Carver; A. Beck; E. Reimer; R. Krüger-Carstensen; L. L. De Haan; G. Braathen; V. Dorokhov; H. Fast; E. Kyrö; M. Gil; Z. Lityñska; M. Molyneux; G. Murphy; F. O'Connor; F. Ravegnani; C. Varotsos; J. Wenger; C. Zerefos

1998-01-01

64

The lamina terminalis and its role in fluid and electrolyte homeostasis  

Microsoft Academic Search

The lamina terminalis, which forms most of the anterior wall of the third ventricle, consists of the median preoptic nucleus and two circumventricular organs (CVOs), the subfornical organ and organum vasculosum of the lamina terminalis. These latter two regions lack a blood-brain barrier and, unlike other regions of the brain, are influenced by the hormonal and ionic composition of the

Michael J McKinley; Rüdiger Gerstberger; Michael L Mathai; Brian J Oldfield; Herbert Schmid

1999-01-01

65

Extracting paleo-climate signals from sediment laminae: A new, automated image processing method  

Microsoft Academic Search

Lake sediment laminations commonly represent depositional seasonality in lacustrine environments. Their occurrence and quantitative attributes contain various signals of their depositional environment, limnological conditions and climate. However, the identification and measurement of laminae remains a mainly manual process that is not only tedious and labor intensive, but also subjective and error prone. We present a batch method to identify laminae

S. Q. Gan; C. A. Scholz

2010-01-01

66

Thickness of endoneurial vessel basal lamina area in chronic idiopathic axonal polyneuropathy.  

PubMed

For chronic idiopathic axonal polyneuropathy (CIAP), even after extensive evaluation, no cause has yet been found. Considering the age and sex distribution of patients with this disease, it is possible that vascular disease plays a role in the development of this polyneuropathy. As endoneurial vessel abnormalities can be related to ischemia, we investigated endoneurial vessels in sural nerve biopsies of 18 patients with CIAP. As controls we used sural nerves of 4 patients with diabetes mellitus, 6 patients with hereditary motor and sensory neuropathy type II (HMSN type III) and 10 autopsy cases. Basal lamina area thickness, endothelial cell area, lumen area, and the number of basal laminae, endothelial cells and periendothelial cell nuclei were investigated. Basal lamina area thickness, endoneurial cell area and number of endothelial cell nuclei in CIAP were increased in comparison with HMSN type III, whereas the basal lamina area thickness of patients with CIAP and diabetes mellitus were in the same range. The structure of the basal lamina area in CIAP differed from diabetes mellitus; in diabetes mellitus there was a larger number of lamellae, whereas in CIAP there was an increase in collagen. There was no correlation between basal lamina area thickness and age. In CIAP patients with peripheral vascular disease of the legs, basal lamina area thickness was increased. The relation between basal lamina area thickening and peripheral vascular disease of the legs in CIAP may indicate a role for ischemia in the development of this polyneuropathy. PMID:10985705

Teunissen, L L; Notermans, N C; Jansen, G H; Banga, J D; Veldman, H; Wokke, J H

2000-10-01

67

The fracture resistance of layered DRA materials: Influence of laminae thickness  

Microsoft Academic Search

The effect of changes in laminae thickness on the fracture toughness of layered discontinuously reinforced aluminum (DRA) materials tested in the crack divider orientation was studied. Toughness was measured on monolithic DRA materials and layered DRA materials consisting of two layers of DRA materials and one layer of monolithic aluminum. The fracture toughness of the individual DRA laminae was not

Todd M. Osman; John J. Lewandowski; Donald R. Lesuer

1997-01-01

68

Extracting paleo-climate signals from sediment laminae: A new, automated image processing method  

NASA Astrophysics Data System (ADS)

Lake sediment laminations commonly represent depositional seasonality in lacustrine environments. Their occurrence and quantitative attributes contain various signals of their depositional environment, limnological conditions and climate. However, the identification and measurement of laminae remains a mainly manual process that is not only tedious and labor intensive, but also subjective and error prone. We present a batch method to identify laminae and extract lamina properties automatically and accurately from sediment core images. Our algorithm is focused on image enhancement that improves the signal-to-noise ratio and maximizes and normalizes image contrast. The unique feature of these algorithms is that they are all direction-sensitive, i.e., the algorithms treat images in the horizontal direction and vertical direction differently and independently. The core process of lamina identification is to use a one-dimensional (1-D) lamina identification algorithm to produce a lamina map, and to use image blob analyses and lamina connectivity analyses to aggregate and smash two-dimensional (2-D) lamina data for the best representation of fine-scale stratigraphy in the sediment profile. The primary output datasets of the system are definitions of laminae and primary color values for each pixel and each lamina in the depth direction; other derived datasets can be retrieved at users’ discretion. Sediment core images from Lake Hitchcock , USA and Lake Bosumtwi, Ghana, were used for algorithm development and testing. As a demonstration of the utility of the software, we processed sediment core images from the top of 50 meters of drill core (representing the past ~100 ky) from Lake Bosumtwi, Ghana.

Gan, S. Q.; Scholz, C. A.

2010-12-01

69

Globular and asymmetric acetylcholinesterase in frog muscle basal lamina sheaths  

PubMed Central

After denervation in vivo, the frog cutaneus pectoris muscle can be led to degenerate by sectioning the muscle fibers on both sides of the region rich in motor endplate, leaving, 2 wk later, a muscle bridge containing the basal lamina (BL) sheaths of the muscle fibers (28). This preparation still contains various tissue remnants and some acetylcholine receptor-containing membranes. A further mild extraction by Triton X-100, a nonionic detergent, gives a pure BL sheath preparation, devoid of acetylcholine receptors. At the electron microscope level, this latter preparation is essentially composed of the muscle BL with no attached plasmic membrane and cellular component originating from Schwann cells or macrophages. Acetylcholinesterase is still present in high amounts in this BL sheath preparation. In both preparations, five major molecular forms (18, 14, 11, 6, and 3.5 S) can be identified that have either an asymmetric or a globular character. Their relative amount is found to be very similar in the BL and in the motor endplate-rich region of control muscle. Thus, observations show that all acetylcholinesterase forms can be accumulated in frog muscle BL.

1986-01-01

70

Dynamics of Lamin-A Processing Following Precursor Accumulation  

PubMed Central

Lamin A (LaA) is a component of the nuclear lamina, an intermediate filament meshwork that underlies the inner nuclear membrane (INM) of the nuclear envelope (NE). Newly synthesized prelamin A (PreA) undergoes extensive processing involving C-terminal farnesylation followed by proteolysis yielding non-farnesylated mature lamin A. Different inhibitors of these processing events are currently used therapeutically. Hutchinson-Gilford Progeria Syndrome (HGPS) is most commonly caused by mutations leading to an accumulation of a farnesylated LaA isoform, prompting a clinical trial using farnesyltransferase inhibitors (FTI) to reduce this modification. At therapeutic levels, HIV protease inhibitors (PI) can unexpectedly inhibit the final processing step in PreA maturation. We have examined the dynamics of LaA processing and associated cellular effects during PI or FTI treatment and following inhibitor washout. While PI reversibility was rapid, with respect to both LaA maturation and associated cellular phenotype, recovery from FTI treatment was more gradual. FTI reversibility is influenced by both cell type and rate of proliferation. These results suggest a less static lamin network than has previously been observed.

Liu, Qian; Kim, Dae In; Syme, Janet; LuValle, Phyllis; Burke, Brian; Roux, Kyle J.

2010-01-01

71

The proteome of mouse brain microvessel membranes and basal lamina  

PubMed Central

The blood–brain barrier (BBB) is a multicellular vascular structure separating blood from the brain parenchyma that is composed of endothelial cells with tight intercellular junctions, surrounded by a basal lamina, astrocytes, and pericytes. Previous studies have generated detailed databases of the microvessel transcriptome; however, less information is available on the BBB at the protein level. In this study, we specifically focused on characterization of the membrane fraction of cells within the BBB to generate a more complete understanding of membrane transporters, tight junction proteins, and associated extracellular matrix proteins that are functional hallmarks of the BBB. We used Multidimensional Protein Identification Technology to identify a total of 1,143 proteins in mouse brain microvessels, of which 53% were determined to be membrane associated. Analyses of specific classes of BBB-associated proteins in the context of recent transcriptome reports provide a unique database to assess the relative contribution of genes at the level of both RNA and protein in the maintenance of normal BBB integrity.

Chun, Hyun Bae; Scott, Michael; Niessen, Sherry; Hoover, Heather; Baird, Andrew; Yates, John; Torbett, Bruce E; Eliceiri, Brian P

2011-01-01

72

A method for preparing skeletal muscle fiber basal laminae  

SciTech Connect

Previous attempts to prepare skeletal muscle basal laminae (BL) for ultrastructural analyses have been hampered by difficulties in successfully removing skeletal muscle proteins and cellular debris from BL tubes. In the present study the authors describe a two phase method which results in an acellular muscle preparation, the BL of which are examined by light, transmission electron, and scanning electron microscopy. In the first phase, excised rat extensor digitorum longus muscles are subjected to x-radiation and then soaked in Marcaine to inhibit muscle regeneration and to destroy peripheral muscle fibers. The muscles are then grafted back into their original sites and allowed to remain in place 7-14 days to allow for maximal removal of degenerating muscle tissue with minimal scar tissue formation. In the second phase, the muscle grafts are subjected sequentially to EDTA, triton X-100, DNAase, and sodium deoxycholate to remove phagocytizing cells and associated degenerating muscle tissue. These procedures result in translucent, acellular muscle grafts which show numerous empty tubes of BL backed by endomysial collagenous fibers. These preparations should be useful for morphological analyses of isolated muscle BL and for possible in vitro studies by which the biological activity of muscle BL can be examined.

Carlson, E.C.; Carlson, B.M. (University of North Dakota, Grand Forks (USA))

1991-07-01

73

Distribution and Processing of ADAMTS-4, Aggrecan, Versican and Hyaluronan in the Equine Digital Laminae  

PubMed Central

Objective Determine the expression and distribution of A Disintegrin And Metalloproteinase with ThromboSpondin motifs-4 (ADAMTS-4), its substrates aggrecan and versican, and their binding partner hyaluronan in laminae of healthy horses as a step towards determining the role of ADAMTS-4 in laminar pathology. Sample population Front hoof laminae from 8 healthy horses. Procedures Real-time quantitative polymerase chain reaction was used for gene expression analysis. Hyaluronidase, chondroitinase and keratanase digestion of lamina extracts together with sodium dodecylsulfate polyacrylamide gel electrophoresis and Western blotting were used for protein and proteoglycan analysis. Immunofluorescent and immunohistochemical staining of tissue sections were used for protein and hyaluronan localization. Results Genes encoding ADAMTS-4, aggrecan, versican and hyaluronan synthase II are expressed in laminae. ADAMTS-4 is predominantly present as a 51 kDa protein bearing a catalytic site neoepitope indicative of active enzyme and in situ activity is inferred from the presence of aggrecan and versican fragments bearing ADAMTS-4 cleavage neoepitopes in laminar protein extracts. Aggrecan, versican and hyaluronan localize to basal epithelial cells within the secondary dermal laminae. ADAMTS-4 also localizes to these cells, but in addition, is present in some cells in the dermal laminae. Conclusions and clinical relevance Within the digital laminae, versican exclusively and aggrecan primarily localizes within basal epithelial cells and both are constitutively cleaved by ADAMTS-4 which therefore contributes to their turnover. Based on known properties of these proteoglycans, it is possible that they protect the basal epithelial cells from biomechanical and concussive stress.

Pawlak, Erica; Wang, Le; Johnson, Philip J.; Nuovo, Gerard; Taye, Almaz; Belknap, James K.; Alfandari, Dominique; Black, Samuel J.

2012-01-01

74

Axon Diversity of Lamina I Local-Circuit Neurons in the Lumbar Spinal Cord  

PubMed Central

Spinal lamina I is a key area for relaying and integrating information from nociceptive primary afferents with various other sources of inputs. Although lamina I projection neurons have been intensively studied, much less attention has been given to local-circuit neurons (LCNs), which form the majority of the lamina I neuronal population. In this work the infrared light-emitting diode oblique illumination technique was used to visualize and label LCNs, allowing reconstruction and analysis of their dendritic and extensive axonal trees. We show that the majority of lamina I neurons with locally branching axons fall into the multipolar (with ventrally protruding dendrites) and flattened (dendrites limited to lamina I) somatodendritic categories. Analysis of their axons revealed that the initial myelinated part gives rise to several unmyelinated small-diameter branches that have a high number of densely packed, large varicosities and an extensive rostrocaudal (two or three segments), mediolateral, and dorsoventral (reaching laminae III–IV) distribution. The extent of the axon and the occasional presence of long, solitary branches suggest that LCNs may also form short and long propriospinal connections. We also found that the distribution of axon varicosities and terminal field locations show substantial heterogeneity and that a substantial portion of LCNs is inhibitory. Our observations indicate that LCNs of lamina I form intersegmental as well as interlaminar connections and may govern large numbers of neurons, providing anatomical substrate for rostrocaudal “processing units” in the dorsal horn. J. Comp. Neurol. 521:2719–2741, 2013.

Szucs, Peter; Luz, Liliana L; Pinho, Raquel; Aguiar, Paulo; Antal, Zsofia; Tiong, Sheena YX; Todd, Andrew J; Safronov, Boris V

2013-01-01

75

A simple method for isolation of DNA fragments associated with the nuclear lamina in vivo.  

PubMed

We describe a simple method for the purification of DNA fragments associated with the nuclear lamina in vivo. Ehrlich ascite tumor cells are first u.v.-irradiated to crosslink DNA to proteins. The nuclear lamina is then isolated and purified by low-speed centrifugation through a cushion of 40% sucrose. The material sedimenting through the created density barrier represents nuclear lamina of a very high purity, free from any DNA fragments except those which were in a crosslinking distance to it in vivo. PMID:2313033

Christova, R; Galcheva-Gargova, Z

1990-01-01

76

Modified endoscopic submucosal dissection with enucleation for treatment of gastric subepithelial tumors originating from the muscularis propria layer  

PubMed Central

Background Gastric subepithelial tumors are usually asymptomatic and observed incidentally during endoscopic examination. Although most of these tumors are considered benign, some have a potential for malignant transformation, particularly those originating from the muscularis propria layer. For this type of tumor, surgical resection is the standard treatment of choice. With recent advent of endoscopic resection techniques and devices, endoscopic submucosal dissection (ESD) has been considered as an alternative way of treatment. The aim of this study is to demonstrate the feasibility of a modified ESD technique with enucleation for removal of gastric subepithelial tumors originating from the muscularis propria layer, and to evaluate its efficacy and safety. Methods From November 2009 to May 2011, a total of 16 patients received a modified ESD with enucleation for their subepithelial tumors. All tumors were smaller than 5?cm and originated from the muscularis propria layer of the stomach, as shown by endoscopic ultrasonography (EUS). The procedure was conducted with an insulated-tip knife 2. Patient’s demographics, tumor size and pathological diagnosis, procedure time, procedure-related complication, and treatment outcome were reviewed. Results Fifteen of the sixteen tumors were successful complete resection. The mean tumor size measured by EUS was 26.1?mm (range: 20–42?mm). The mean procedure time was 52?minutes (range: 30–120?minutes). Endoscopic features of the 4 tumors were pedunculated and 12 were sessile. Their immunohistochemical diagnosis was c-kit (+) stromal tumor in 14 patients and leiomyoma in 2 patients. There was no procedure-related perforation or overt bleeding. During a mean follow up duration of 14.8?months (range: 6–22?months), there was no tumor recurrence or metastasis. Conclusions Using a modified ESD with enucleation for treatment of gastric subepithelial tumors originating from the muscularis propria layer and larger than 2?cm, complete resection can be successfully performed without serious complication. It is a safe and effective alternative to surgical therapy for these tumors of 2 to 5?cm in size.

2012-01-01

77

Robust Internal Elastic Lamina Fenestration in Skeletal Muscle Arteries  

PubMed Central

Holes within the internal elastic lamina (IEL) of blood vessels are sites of fenestration allowing for passage of diffusible vasoactive substances and interface of endothelial cell membrane projections with underlying vascular smooth muscle. Endothelial projections are sites of dynamic Ca2+ events leading to endothelium dependent hyperpolarization (EDH)-mediated relaxations and the activity of these events increase as vessel diameter decreases. We tested the hypothesis that IEL fenestration is greater in distal vs. proximal arteries in skeletal muscle, and is unlike other vascular beds (mesentery). We also determined ion channel protein composition within the endothelium of intramuscular and non-intramuscular skeletal muscle arteries. Popliteal arteries, subsequent gastrocnemius feed arteries, and first and second order intramuscular arterioles from rat hindlimb were isolated, cut longitudinally, fixed, and imaged using confocal microscopy. Quantitative analysis revealed a significantly larger total fenestration area in second and first order arterioles vs. feed and popliteal arteries (58% and 16% vs. 5% and 3%; N?=?10 images/artery), due to a noticeably greater average size of holes (9.5 and 3.9 µm2 vs 1.5 and 1.9 µm2). Next, we investigated via immunolabeling procedures whether proteins involved in EDH often embedded in endothelial cell projections were disparate between arterial segments. Specific proteins involved in EDH, such as inositol trisphosphate receptors, small and intermediate conductance Ca2+-activated K+ channels, and the canonical (C) transient receptor potential (TRP) channel TRPC3 were present in both popliteal and first order intramuscular arterioles. However due to larger IEL fenestration in first order arterioles, a larger spanning area of EDH proteins is observed proximal to the smooth muscle cell plasma membrane. These observations highlight the robust area of fenestration within intramuscular arterioles and indicate that the anatomical architecture and endothelial cell hyperpolarizing apparatus for distinct vasodilatory signaling is potentially present.

Sullivan, Michelle N.; Francis, Michael; Dinenno, Frank A.; Earley, Scott

2013-01-01

78

Arterial internal elastic lamina holes: relationship to function?  

PubMed Central

Internal elastic lamina (IEL) hole (fenestration) characteristics and myoendothelial gap junction (MEGJ) density were examined in selected resistance and conduit arteries of normal and diseased rat and mouse models, using conventional, ultrastructural and confocal microscopy methods. Selected vessels were those commonly used in functional studies: thoracic aorta, proximal and distal mesenteric, caudal, saphenous, middle-cerebral and caudal cerebellar artery. Rat and mouse strains and treatment groups examined were Dahl, Sprague Dawley, Wistar Kyoto, Wistar, spontaneously hypertensive (SHR), deoxycorticosterone (DOC) treated rat; and apolipoprotein E knockout, C57/BL6 and BALB/c mice. Vessel size (as IEL circumference), IEL hole and MEGJ density were quantified. In mesenteric arteries, the width of IEL holes and the percent of IEL occupied by holes were also determined. IEL hole density varied significantly within and between mesenteric artery beds, even among normotensive rat strains. Among the hypertensive rats (SHR and DOC), hole density in some vessels was higher in the normotensives than in the hypertensives within each strain, whereas in Dahl rats, hole density was similar between hypertensives and normotensives. Hole density was not correlated with the formation of intimal lesions in superior mesenteric artery. There was no positive general correlation between IEL hole and MEGJ density in resistance and conduit vessels. However, there was a positive correlation between the size of some resistance arteries and MEGJ density, although such a relationship did not hold for conduit vessels or during development, and there was no such relationship between vessel size and IEL hole density. Whilst IEL holes are obviously required for MEGJ communication, their presence is not an indication of contact-mediated communication, but rather may be related to the presence of sites for the low resistance passage of diffusion-mediated release of vasoactive endothelial and smooth muscle substances.

Sandow, Shaun L; Gzik, Danusia J; Lee, Robert M K W

2009-01-01

79

Three dimensional analysis of the lamina cribrosa in glaucoma  

PubMed Central

Background/aim: Structural changes in the lamina cribrosa have been implicated in the pathogenesis of glaucomatous optic atrophy. The aim of this study was to determine a measure the surface variability of the cup floor in normal subjects and patients with glaucoma. Methods: A sample of age matched normal subjects (NN), patients with low tension glaucoma (LTG), and primary open angle glaucoma (POAG) were included in the study. The glaucoma groups were matched for the severity of the visual field loss. Mean 10 degree topographic images of normal and glaucomatous eyes from the Heidelberg retina tomograph were imported into ERDAS image processing software where topographic analysis of the cup floor could be assessed. Each image was processed using customised spatial filters that calculated the surface depth variation in localised neighbourhood areas across each image. The local change in depth across the cup floor surface was determined and compared between the three clinical groups. Results: The depth variation in the cup floor was largest in normal subjects followed by LTG and POAG. Highly statistically significant differences in surface depth variability of the cup floor existed between normal and LTG (p?=?0.005), between normal and POAG (p<0.0001), and between LTG and POAG groups (p<0.0001). The variability and skewness of depth difference across the optic cup floor were also significantly different between the three clinical groups. Conclusion: A new parameter quantifying depth variations in the cup floor significantly discriminated between groups of normal and glaucoma patients. This new parameter may contribute to a better understanding of the pathogenesis of the glaucomatous optic nerve damage in different types of glaucoma.

Morgan-Davies, J; Taylor, N; Hill, A R; Aspinall, P; O'Brien, C J; Azuara-Blanco, A

2004-01-01

80

A novel method for quantification of the folding of elastic laminae in elastic arteries.  

PubMed

A transgenic mouse overexpressing the human form of semicarbazide-sensitive amine oxidase (SSAO) is known to have an abnormal structure of the elastic laminae and the elastic fibres in the aorta. Compared to the non-transgenic littermates, the elastic laminae are less folded. In order to quantify the undulation of this structure, an image analysis program that identified the elastic laminae was developed. The program measures the area fraction in different sectors from a plane parallel to the aorta wall. Images were taken from unstained aorta specimens where the elastic laminae were visualised with phase contrast microscopy. A contextual operation of the images produced a local orientation estimation for every linear structure. The image was then thresholded in eight sectors from 0 degrees to 180 degrees , with different orientation angles. The results show that the area fraction of the elastic laminae was significantly lower for the transgenic mouse in all sectors measured except for two. At 0-25 degrees , no difference was seen. In the sector at 160-180 degrees , parallel to the aorta wall, the area fraction of elastic laminae was instead significantly higher in the transgenic mouse. A novel method is presented, developed for detection and quantification of pathological changes in the elastic laminae in the aorta wall. The method gave reliable results and is considered to be a useful tool for morphometric studies of aorta with this kind of altered morphology concerning the elastic laminae. When compared with tangent count, the control group had a significantly larger mean curvature. PMID:17485215

Blomgren, Bo; Göktürk, Camilla

2007-03-30

81

Morphology and physiology of lamina I neurons of the caudal part of the trigeminal nucleus  

Microsoft Academic Search

It has been suggested that in mammals, trigeminal lamina I neurons play a role in the processing and transmission of sensory information from the orofacial region. We investigated the physiological and morphological properties of trigeminal subnucleus caudalis (Sp5C) lamina I neurons in slices prepared from the medulla oblongata of 13- to 15-day-old postnatal rats using patch-clamp recordings and subsequent biocytin–streptavidin–Alexa

M. Sedlacek; M. Horak; L VYKLICKYJR

2007-01-01

82

The hydraulic conductance of the angiosperm leaf lamina: a comparison of three measurement methods.  

PubMed

A comparison was made of three methods for measuring the leaf lamina hydraulic conductance (K(lamina)) for detached mature leaves of six woody temperate angiosperm species. The high-pressure method, the evaporative flux method and the vacuum pump method involve, respectively, pushing, evaporating and pulling water out of the lamina while determining the flow rate into the petiole and the water potential drop across the leaf. Tests were made of whether the high-pressure method and vacuum pump method measurements of K(lamina) on single leaves were affected by irradiance. In Quercus rubra, the high pressure method was sensitive to irradiance; K(lamina) measured under high irradiance (>1200 micro mol m(-2) s(-1 )photosynthetically active radiation) was 4.6-8.8 times larger than under ambient laboratory lighting (approximately 6 micro mol m(-2) s(-1 )photosynthetically active radiation). By constrast, the vacuum pump method was theoretically expected to be insensitive to irradiance, and this expectation was confirmed in experiments on Hedera helix. When used in the ways recommended here, the three methods produced measurements that agreed typically within 10%. There were significant differences in species' K(lamina); values ranged from 1.24x10(-4) kg s(-1) m(-2) MPa(-1) for Acer saccharum to 2.89x10(-4) kg s(-1) m(-2) MPa(-1) for Vitis labrusca. Accurate, rapid determination of K(lamina) will allow testing of the links between K(lamina), water-use, drought tolerance, and the enormous diversity of leaf form, structure and composition. PMID:12379784

Sack, Lawren; Melcher, Peter J; Zwieniecki, Maciej A; Holbrook, N Michele

2002-11-01

83

Responses of Trapa natans L. floating laminae to high concentrations of manganese  

Microsoft Academic Search

Summary.  The present study focuses on the responses of floating laminae of the Mn-tolerant hydrophyte Trapa natans L. to 1 mM Mn and their ability to accumulate the metal. Studies were carried out first on young floating laminae belonging\\u000a to the second verticil of 30-day-old plants which originated from fruits that had been maintained in a 1 mM Mn-treated environment\\u000a and

C. Baldisserotto; L. Ferroni; E. Anfuso; A. Pagnoni; M. P. Fasulo; S. Pancaldi

2007-01-01

84

Dynamic Failure of a Lamina Meshwork in Cell Nuclei under Extreme Mechanical Deformation  

Microsoft Academic Search

The nuclear lamina is a structural protein meshwork at the inner nuclear membrane. It confers mechanical strength to the cell’s\\u000a nucleus and also sustains the overall structural integrity of the cell. The rupture of nuclear lamina is involved in many\\u000a physiologically extreme conditions, such as cell division, genetic disease, and injury. Yet, its rupture mechanisms and processes\\u000a are largely unknown

Zhao Qin; Markus J. Buehler

2011-01-01

85

Roller micrometer analysis of grain size and shape sorting within sand laminae from lacustrine barrier islands  

SciTech Connect

The dynamics of sand lamination deposition were investigated for two barrier islands in Lake Erie: Cedar Point Spit, Ohio, and Presque Isle, Pennsylvania. A new measurement technique, roller micrometer analysis, was used to describe the grain size and shape distributions of samples. This technique mechanically sizes grains by both the intermediate (I) and smallest (S) principal dimensions and thus divides a sample into fractions containing grains with common I and S dimensions and tabularity (S/I) ratio. Portions of the two barrier islands are subject to overwashing by wind-driven lake waters. During such events foreshore laminae are eroded and the sand is redeposited in washover fan topset and foreset laminae. At other times, normal wave activity reworks the washover fan deposits into foreshore laminae. In the transport of sand across the barrier islands from the lake margin (foreshore laminae) through the interior (fan topset laminae) and to the lagoon margin (fan foreset laminae), the following trends are observed: mean grain size increases, grain size sorting become poorer, grain size skewness becomes coarser, and, for grains of the same size, the proportion of more tabular grains decreases. These trends indicate, in a lagoonward direction, progressive winnowing from the bed load of the finer and more tabular grains and increased intermixing of the remaining coarser bed load grains. Roller micrometer analysis is an important new tool for sedimentologists. It provides traditional grain-size distribution data along with the distribution of grain tabularity. Together the two distributions are sensitive indicators of winnowing and selective deposition.

Harrell, J.A.; Braun, R.B.

1987-05-01

86

Rupture of the internal elastic lamina and vascular fragility in stroke-prone spontaneously hypertensive rats.  

PubMed

We studied a possible relation between stroke and an enhanced susceptibility to rupture of the arterial internal elastic lamina by comparing stroke-prone spontaneously hypertensive rats with spontaneously hypertensive rats, which have a very low incidence of stroke. We quantified interruptions in the internal elastic lamina in certain arteries and studied the effect of beta-aminopropionitrile, an inhibitor of cross-link formation in collagen and elastic fibers, on rupture of the internal elastic lamina and on mortality in these two substrains. To eliminate any influence of higher blood pressure in the stroke-prone rats on the parameters studied, we used antihypertensive treatment to obtain equivalent blood pressures in the two substrains. Results showed that stroke sensitivity was associated with an enhanced early spontaneous rupture of the internal elastic lamina in the caudal artery, an increased susceptibility to beta-aminopropionitrile-induced rupture of the internal elastic lamina, and earlier mortality, mainly from aortic rupture, under beta-aminopropionitrile treatment. These findings suggest that stroke-prone rats have an enhanced minor connective tissue defect that is expressed by rupture of the internal elastic lamina and may be related, at least in part, to their greater vascular fragility and increased susceptibility to stroke. PMID:2024280

Coutard, M; Osborne-Pellegrin, M

1991-04-01

87

Lack of vessel wall elastolysis in human invasive pulmonary aspergillosis.  

PubMed Central

In experimental studies, the apparent ability of Aspergillus fumigatus isolates to produce elastase in agar plates correlates with their ability to cause invasive pulmonary aspergillosis in mice pretreated with cortisone. Thus, elastase production may govern the pathogenicity of particular isolates. If this is so, then disruption of the elastic layers within blood vessel walls in invasive aspergillosis would be expected. To test this hypothesis, tissue blocks were prepared from nine patients with invasive pulmonary aspergillosis. Separate but immediately adjacent histological sections were stained by the Grocott and periodic acid-Schiff methods for fungal hyphae and by the elastic van Gieson technique for elastic tissue. Comparison of those segments of vessel walls infiltrated by hyphae with those not infiltrated by hyphae showed no overall loss of elastic tissue. Material from five of the cases was also stained with an unconventional combination of histochemical stains, allowing accurate identification of both fungal hyphae and elastic laminae in the same histological sections. The results showed no more disruption of elastic laminae than would be expected from simple physical displacement of elastic laminae. We conclude that if elastolysis contributes at all to invasion of vessel walls by aspergilli, then it seems to be very localized and/or transient. Images

Denning, D W; Ward, P N; Fenelon, L E; Benbow, E W

1992-01-01

88

[Thomas Ionescu versus Wildhem von Waldeyer. Rectum sheath or fascia propria recti? The story of a wandering idea].  

PubMed

Anatomical knowledge of rectum and its fascial relationship is crucial in modem surgery and it represents the basis of total mesorectal excision. Most of the contemporary authors make reference to Waldeyer's description and use the name fascia propria recti. However, there are evidence regarding Thomas Jonnesco's priority in describing this fascial structure 5 years before Waldeyer. Thomas Jonnesco's description was published in a famous anatomy textbook: Traité d'Anatomie Humaine, Paris, Bataille, 1894, editor P. Poirier, where Thomas Jonnesco was the author of volume 4, fascicule 1, containing the anatomy of the digestive system. His description of the rectum sheath precedes Waldeyer's publication (Das Becken, Cohen, Bonn, 1899). The description of the rectum sheath is included also into the second edition of Traité d'Anatomie Humaine (editors P. Poirier and A. Charpy) published again in 1901 at Masson Publishing House. This second version, better known by contemporary authors (Chapuis et al. Dis Colon Rectum 2002;45:1), probably revised by Charpy, is no more so simple and so clear as the first one. In our paper Thomas Jonnesco's original description of rectal fascia (rectum sheath), published in 1894, is facsimiled, the two succesive editions of the book are compared and a comparison with Waldeyer's description of fascia propria recti is done. The priority of Thomas Jonnesco seems to be well proved. In this respect our own research is in line with the observations of Chapuis and Bell si colab. PMID:20726295

Vasilescu, C

89

Biological Invasions  

Microsoft Academic Search

\\u000a Biological invasions can have powerful effects on ecosystem structure and function and are seen as a threat to global biodiversity.\\u000a Coastal systems are especially vulnerable, and we review the characteristics of invasions in marine benthic communities, beginning\\u000a with the factors influencing initial introduction: vectors and propagule pressure. Invasive species have few characteristics\\u000a in common, and their ease of establishment in

Christopher D. McQuaid; Francisco Arenas

90

The Meiotic Nuclear Lamina Regulates Chromosome Dynamics and Promotes Efficient Homologous Recombination in the Mouse  

PubMed Central

The nuclear lamina is the structural scaffold of the nuclear envelope and is well known for its central role in nuclear organization and maintaining nuclear stability and shape. In the past, a number of severe human disorders have been identified to be associated with mutations in lamins. Extensive research on this topic has provided novel important clues about nuclear lamina function. These studies have contributed to the knowledge that the lamina constitutes a complex multifunctional platform combining both structural and regulatory functions. Here, we report that, in addition to the previously demonstrated significance for somatic cell differentiation and maintenance, the nuclear lamina is also an essential determinant for germ cell development. Both male and female mice lacking the short meiosis-specific A-type lamin C2 have a severely defective meiosis, which at least in the male results in infertility. Detailed analysis revealed that lamin C2 is required for telomere-driven dynamic repositioning of meiotic chromosomes. Loss of lamin C2 affects precise synapsis of the homologs and interferes with meiotic double-strand break repair. Taken together, our data explain how the nuclear lamina contributes to meiotic chromosome behaviour and accurate genome haploidization on a mechanistic level.

Schmitt, Johannes; Gob, Eva; Baar, Johannes; Ortega, Sagrario; Benavente, Ricardo; Alsheimer, Manfred

2013-01-01

91

Distinct structural and mechanical properties of the nuclear lamina in Hutchinson-Gilford progeria syndrome  

PubMed Central

The nuclear lamina is a network of structural filaments, the A and B type lamins, located at the nuclear envelope and throughout the nucleus. Lamin filaments provide the nucleus with mechanical stability and support many basic activities, including gene regulation. Mutations in LMNA, the gene encoding A type lamins, cause numerous human diseases, including the segmental premature aging disease Hutchinson–Gilford progeria syndrome (HGPS). Here we show that structural and mechanical properties of the lamina are altered in HGPS cells. We demonstrate by live-cell imaging and biochemical analysis that lamins A and C become trapped at the nuclear periphery in HGPS patient cells. Using micropipette aspiration, we show that the lamina in HGPS cells has a significantly reduced ability to rearrange under mechanical stress. Based on polarization microscopy results, we suggest that the lamins are disordered in the healthy nuclei, whereas the lamins in HGPS nuclei form orientationally ordered microdomains. The reduced deformability of the HGPS nuclear lamina possibly could be due to the inability of these orientationally ordered microdomains to dissipate mechanical stress. Surprisingly, intact HGPS cells exhibited a degree of resistance to acute mechanical stress similar to that of cells from healthy individuals. Thus, in contrast to the nuclear fragility seen in lmna null cells, the lamina network in HGPS cells has unique mechanical properties that might contribute to disease phenotypes by affecting responses to mechanical force and misregulation of mechanosensitive gene expression.

Dahl, Kris Noel; Scaffidi, Paola; Islam, Mohammad F.; Yodh, Arjun G.; Wilson, Katherine L.; Misteli, Tom

2006-01-01

92

Application of lamina replantation with ARCH plate fixation in thoracic and lumbar intraspinal tumors  

PubMed Central

The aim of the present study was to investigate the clinical effects of lamina replantation with ARCH plate fixation on patients with thoracic and lumbar intraspinal tumors, following laminectomy. Thirteen patients with thoracic and lumbar intraspinal tumors underwent total lamina replantation with ARCH plate fixation and repair of the supraspinous ligaments, following laminectomy and tumor enucleation. To investigate the clinical effect of lamina replantation with ARCH plate fixation, pre- and postoperative visual analog scale (VAS), and Oswestry Disability Index (ODI) scores were determined, and pre- and postoperative X-ray and magnetic resonance imaging (MRI) examinations were conducted. Computed tomography (CT) examinations were also included in the follow-up. No complications were observed pre- or postoperatively. The VAS and ODI results 2 weeks following surgery and at the final follow-up examination demonstrated a significant improvement compared with the corresponding preoperative results. The X-ray examination results indicated a satisfactory internal fixation location, without any characteristics of a fracture, lumbar scoliosis, kyphosis or instability. Following the surgery, the CT and MRI examination results demonstrated that healing of the lamina bone and repair of the supraspinous ligament had occurred without tumor recurrence or spinal epidural scar recompression. Two of the 13 cases were lost to follow-up. The results indicated that in patients with thoracic and lumbar intraspinal tumors, lamina replantation with ARCH plate fixation following total laminectomy is effective and provides thoracolumbar stability. Furthermore, this has been identified to be an effective technique for preventing intraspinal scar proliferation.

ZHOU, DONG; NONG, LU-MING; GAO, GONG-MIN; JIANG, YU-QIN; XU, NAN-WEI

2013-01-01

93

Specific stimulation of basal lamina heparan sulfate proteoglycan in mouse uterine epithelium by matrigel and by transforming growth factor-?1  

Microsoft Academic Search

Summary  The basal lamina of differentiated epithelium normally turns over only slowly unless stimulated by tissue repair and growth.\\u000a We show here that one mechanism of this stimulation, as modeled by basal lamina proteoglycan synthesis, may be the release\\u000a of basal lamina-bound transforming growth factor (TGF-?). A large heparan sulfate proteoglycan (HSPG, 0.2K\\u000a av on Sepharose CL-4B) that was extractable from

John E. Morris; Georgeen Gaza; Sandra W. Potter

1994-01-01

94

Galanin-immunoreactivity identifies a distinct population of inhibitory interneurons in laminae I-III of the rat spinal cord  

PubMed Central

Background Inhibitory interneurons constitute 30-40% of neurons in laminae I-III and have an important anti-nociceptive role. However, because of the difficulty in classifying them we know little about their organisation. Previous studies have identified 3 non-overlapping groups of inhibitory interneuron, which contain neuropeptide Y (NPY), neuronal nitric oxide synthase (nNOS) or parvalbumin, and have shown that these differ in postsynaptic targets. Some inhibitory interneurons contain galanin and the first aim of this study was to determine whether these form a different population from those containing NPY, nNOS or parvalbumin. We also estimated the proportion of neurons and GABAergic axons that contain galanin in laminae I-III. Results Galanin cells were concentrated in laminae I-IIo, with few in laminae IIi-III. Galanin showed minimal co-localisation with NPY, nNOS or parvalbumin in laminae I-II, but most galanin-containing cells in lamina III were nNOS-positive. Galanin cells constituted ~7%, 3% and 2% of all neurons in laminae I, II and III, and we estimate that this corresponds to 26%, 10% and 5% of the GABAergic neurons in these laminae. However, galanin was only found in ~6% of GABAergic boutons in laminae I-IIo, and ~1% of those in laminae IIi-III. Conclusions These results show that galanin, NPY, nNOS and parvalbumin can be used to define four distinct neurochemical populations of inhibitory interneurons. Together with results of a recent study, they suggest that the galanin and NPY populations account for around half of the inhibitory interneurons in lamina I and a quarter of those in lamina II.

2011-01-01

95

Invasive Candidiasis  

MedlinePLUS

... Fungal Homepage. Invasive Candidiasis Topics Definition What is invasive candidiasis? Symptoms Non-specific fever and chills… Risk & Prevention Who gets it and how it can be prevented… Sources of Infection Candida species are normal inhabitants of the skin and mucous ...

96

Streptococcal invasion  

Microsoft Academic Search

The genus Streptococcus consists of large number of species many of which are pathogenic to humans and animals. Although streptococci have long been considered as extracellular pathogens, they are capable of causing serious invasive infections such as necrotizing fasciitis and meningitis. Streptococcal invasion, therefore, has been a focus of many studies in recent years. Streptococci are efficiently internalized by nonprofessional

Gabriella Molinari; Gursharan S Chhatwal

1999-01-01

97

Bullous pemphigoid: role of complement and mechanisms for blister formation within the lamina lucida.  

PubMed

Bullous pemphigoid (BP), an autoimmune subepidermal blistering skin disease, demonstrates tense blisters with or without widespread erythema, blistering along the lamina lucida, immunoglobulin G and/or complement deposits at the basement membrane zone, and the presence of circulating autoantibodies against hemidesmosomal molecules. These autoantibodies usually react against 180-kDa and/or 230-kDa proteins, designated as BP180 and BP230, respectively. The precise blistering mechanisms after autoantibodies bind to antigens are not fully understood. Immune complexes are thought to initially activate the complement cascade, which may induce activation of proteases and/or cytokines and cause dermal-epidermal separation. However, why does separation run specifically within the lamina lucida in a space as narrow as 500 nm wide? This review mainly focuses on the possible mechanisms of BP-specific blistering and how separation occurs along the lamina lucida, based on existing evidence. PMID:23651418

Iwata, Hiroaki; Kitajima, Yasuo

2013-05-07

98

Ligation-assisted endoscopic enucleation for the diagnosis and resection of small gastrointestinal tumors originating from the muscularis propria: a preliminary study  

PubMed Central

Background Ligation-assisted endoscopic enucleation (EE-L) was developed for the pathological diagnosis and resection of small gastrointestinal tumors originating from the muscularis propria. The technique combines endoscopic band ligation and endoscopic enucleation. The aim of this study was to evaluate the efficacy and safety of EE-L in the diagnosis and resection of gastrointestinal tumors originating from the muscularis propria. Methods A total of 43 patients were eligible for inclusion in this study from June 2009 to June 2011. Endoscopic ligation was first performed to force the tumor to assume a polypoid form with a pseudostalk. EE-L was then performed until the tumor was completely enucleated from the muscularis propria. Wound closure was performed using clips and adhesive tissue. Results All 43 tumors were completely enucleated. The mean enucleation time was 7.2 minutes (range, 5–11 minutes). No perforation, massive hemorrhage, or peritonitis requiring further endoscopic or surgical intervention occurred. Histopathology, 19 lesions were identified as gastrointestinal stromal tumors and 24 lesions were identified as leiomyomas. The mean follow-up time was 20.4 months (range, 14–38 months). No recurrence has occurred during the follow-up period. Conclusions EE-L appears to be a safe, effective, and relatively simple method for the histologic diagnosis and removal of small gastrointestinal tumors originating from the muscularis propria.

2013-01-01

99

Streptococcal invasion.  

PubMed

The genus Streptococcus consists of large number of species many of which are pathogenic to humans and animals. Although streptococci have long been considered as extracellular pathogens, they are capable of causing serious invasive infections such as necrotizing fasciitis and meningitis. Streptococcal invasion, therefore, has been a focus of many studies in recent years. Streptococci are efficiently internalized by nonprofessional phagocytes and the current research interest has shifted to determine the role of this invasion in the natural infection process. Moreover, characterization of bacterial and eukaryotic components involved in the uptake process might be useful in developing new strategies for combating streptococcal infections. PMID:10047553

Molinari, G; Chhatwal, G S

1999-02-01

100

Changes in the collagenous matrix of the aging human lamina cribrosa.  

PubMed Central

AIMS--The age-related changes in the biochemical composition of the collagenous matrix of the human lamina cribrosa were investigated. METHODS--An age range (3 weeks to 92 years old) of human laminae cribrosae, dissected free of any surrounding structures which contained collagen, were analysed for collagen solubility (n = 58) total collagen content (n = 46), proportion of collagen types (n = 38), and collagen cross linking (n = 30), using hydroxyproline analysis, scanning densitometry of peptides after cyanogen bromide digestion, and high performance liquid chromatography, respectively. RESULTS--Age-related changes included an increase in total collagen and a decrease in the proportion of type III collagen within the lamina cribrosa. The collagen cross link pyridinoline was present at low levels, but demonstrated no trend with age. An age-related increase was found in pentosidine, an advanced glycation product. CONCLUSION--These changes in collagen composition imply that the mechanical properties of the lamina cribrosa are altered, resulting in a stiffer, less resilient structure with age. Such alterations in structure may contribute to the increased susceptibility of the elderly to axonal damage in chronic open angle glaucoma. Images

Albon, J; Karwatowski, W S; Avery, N; Easty, D L; Duance, V C

1995-01-01

101

Silicifying Biofilm Exopolymers on a Hot-Spring Microstromatolite: Templating Nanometer-Thick Laminae  

NASA Astrophysics Data System (ADS)

Exopolymeric substances (EPS) are an integral component of microbial biofilms; however, few studies have addressed their silicification and preservation in hot-spring deposits. Through comparative analyses with the use of a range of microscopy techniques, we identified abundant EPS significant to the textural development of spicular, microstromatolitic, siliceous sinter at Champagne Pool, Waiotapu, New Zealand. Examination of biofilms coating sinter surfaces by confocal laser scanning microscopy (CLSM), environmental scanning electron microscopy (ESEM), cryo-scanning electron microscopy (cryo-SEM), and transmission electron microscopy (TEM) revealed contraction of the gelatinous EPS matrix into films (approximately 10 nm thick) or fibrillar structures, which is common in conventional SEM analyses and analogous to products of naturally occurring desiccation. Silicification of fibrillar EPS contributed to the formation of filamentous sinter. Matrix surfaces or dehydrated films templated sinter laminae (nanometers to microns thick) that, in places, preserved fenestral voids beneath. Laminae of similar thickness are, in general, common to spicular geyserites. This is the first report to demonstrate EPS templation of siliceous stromatolite laminae. Considering the ubiquity of biofilms on surfaces in hot-spring environments, EPS silicification studies are likely to be important to a better understanding of the origins of laminae in other modern and ancient stromatolitic sinters, and EPS potentially may serve as biosignatures in extraterrestrial rocks.

Handley, Kim M.; Turner, Sue J.; Campbell, Kathleen A.; Mountain, Bruce W.

2008-08-01

102

Agrin Binds to the Nerve-Muscle Basal Lamina via Laminin  

Microsoft Academic Search

Abstract Agrin is a heparan sulfate proteoglycan that is required for the formation and maintenance,of neuromuscular junctions. During development, agrin is secreted from motor neurons to trigger the local aggregation of acetylcholinereceptors (AChRs) and other proteins in the muscle fiber, which together compose the postsynaptic apparatus. After release from the motor neuron, agrin binds to the developing muscle basal lamina

A. J. Denzer

1997-01-01

103

Quantitative basis for neuroimaging of cortical laminae with calibrated functional MRI.  

PubMed

Layer-specific neurophysiologic, hemodynamic, and metabolic measurements are needed to interpret high-resolution functional magnetic resonance imaging (fMRI) data in the cerebral cortex. We examined how neurovascular and neurometabolic couplings vary vertically in the rat's somatosensory cortex. During sensory stimulation we measured dynamic layer-specific responses of local field potential (LFP) and multiunit activity (MUA) as well as blood oxygenation level-dependent (BOLD) signal and cerebral blood volume (CBV) and blood flow (CBF), which in turn were used to calculate changes in oxidative metabolism (CMR(O2)) with calibrated fMRI. Both BOLD signal and CBV decreased from superficial to deep laminae, but these responses were not well correlated with either layer-specific LFP or MUA. However, CBF changes were quite stable across laminae, similar to LFP. However, changes in CMR(O2) and MUA varied across cortex in a correlated manner and both were reduced in superficial lamina. These results lay the framework for quantitative neuroimaging across cortical laminae with calibrated fMRI methods. PMID:23980158

Herman, Peter; Sanganahalli, Basavaraju G; Blumenfeld, Hal; Rothman, Douglas L; Hyder, Fahmeed

2013-08-26

104

A refined hybrid plate theory for composite laminates with piezoelectric laminae  

Microsoft Academic Search

In this paper, a refined theory of laminated composite plates with piezoelectric laminae is developed. The equations of motion of the theory are developed using an energy principle. This formulation is based on linear piezoelectricity, and includes the coupling between mechanical deformations and the charge equations of electrostatics. The theory developed herein is hybrid in the sense that an equivalent

J. A. Mitchell; J. N. Reddy

1995-01-01

105

Emergence of Lamina-Specific Retinal Ganglion Cell Connectivity by Axon Arbor Retraction and Synapse Elimination  

PubMed Central

Throughout the nervous system, neurons restrict their connections to specific depths or ‘layers’ of their targets in order to constrain the type and number of synapses they make. Despite the importance of lamina-specific synaptic connectivity, the mechanisms that give rise to this feature in mammals remain poorly understood. Here we examined the cellular events underlying the formation of lamina-specific retinal ganglion cell (RGC) axonal projections to the superior colliculus (SC) of the mouse. By combining a genetically encoded marker of a defined RGC subtype (OFF-?RGCs) with serial immuno-electron microscopy, we resolved the ultrastructure of axon terminals fated for laminar stabilization versus those fated for removal. We found that OFF-?RGCs form synapses across the full depth of the retinorecipient SC before undergoing lamina-specific arbor retraction and synapse elimination to arrive at their mature, restricted pattern of connectivity. Interestingly, we did not observe evidence of axon degeneration or glia-induced synapse engulfment during this process. These findings indicate that lamina-specific visual connections are generated through the selective stabilization of correctly targeted axon arbors and suggest that the decision to maintain or eliminate an axonal projection reflects the molecular compatibility of pre- and postsynaptic neurons at a given laminar depth.

Cheng, Ting-Wen; Liu, Xiao-Bo; Faulkner, Regina L.; Stephan, Alexander H.; Barres, Ben A.; Huberman, Andrew D.; Cheng, Hwai-Jong

2010-01-01

106

Surface fine structure of the eye of the housefly ( Musca domestica ): Ommatidia and lamina ganglionaris  

Microsoft Academic Search

The compound eye of the housefly, from lens to first optic neuropile (lamina ganglionaris) was examined with a scanning electron microscope. Key findings are as follows: The pseudocone cavity is enclosed by six corneal pigment cells. The nuclei of the six cells are firmly anchored to the underside of the lens and portions remain after lens delamination from the pseudocone

Stanley D. Carlson; Che Chi

1974-01-01

107

Thermoreceptive lamina I trigeminothalamic neurons project to the nucleus submedius in the cat  

Microsoft Academic Search

The technique of antidromic mapping with a roving array of electrodes was used to demonstrate that lamina I trigeminothalamic cells responsive specifically to skin temperature project to the n. submedius (Sm) in the medial thalamus of the cat. This finding indicates that Sm receives thermoreceptive in addition to nociceptive information.

A. D. Craig; J. O. Dostrovsky

1991-01-01

108

NK1 Receptor Immunoreactivity in Distinct Morphological Types of Lamina I Neurons of the Primate Spinal Cord  

Microsoft Academic Search

In cat and monkey, lamina I cells can be classified into three basic morphological types (fusiform, pyramidal, and multipolar), and recent intracellular labeling evidence in the cat indicates that fusiform and multipolar lamina I cells are two different types of nociceptive cells, whereas pyramidal cells are innocuous thermoreceptive-specific. Because earlier observations indi- cated that only nociceptive dorsal horn neurons respond

X. H. Yu; E.-T. Zhang; A. D. Craig; R. Shigemoto; A. Ribeiro-da-Silva; Y. De Koninck

1999-01-01

109

Comparison of nerve cell and nerve cell plus Schwann cell cultures, with particular emphasis on basal lamina and collagen formation  

Microsoft Academic Search

The availability of cultures of normal nerve cells (NCs) and Schwann cells (SCs) with and without fibroblasts has allowed us to investigate the sources of endoneu- rial and perineurial constituents of peripheral nerve . NCs cultured alone, devoid of ensheathment but healthy in appearance, lack basal lamina and extracellular fibrils. In contrast, when SCs accompany NCs, basal lamina and extracellular

M. B. Bunge; ANN K. WILLIAMS; JOUNI UITTO; JOHN J. JEFFREY

1980-01-01

110

A quantitative study of brainstem projections from lamina I neurons in the cervical and lumbar enlargement of the rat  

PubMed Central

Lamina I of the rat spinal cord contains neurons that project to various brain areas including thalamus, periaqueductal grey matter (PAG), lateral parabrachial area (LPb), caudal ventrolateral medulla and a region in dorsal medulla that includes the nucleus tractus solitarius and dorsal reticular nucleus. We have shown that spinothalamic lamina I neurons are infrequent in rat lumbar enlargement, where they constitute ? 5% of the estimated 400 projection neurons on each side of the L4 segment (Al-Khater and Todd, 2009). They are more numerous in cervical enlargement, but the total number of lamina I projection neurons in this region was not known. Here we have used paired injections of retrograde tracers into the brainstem to estimate the number of lamina I projection cells in the C7 segment. Our results suggest that there are ? 215 lamina I projection cells per side, and that spinothalamic cells therefore make up ? 42% of this population. The proportion of lamina I projection neurons labelled from PAG is higher in cervical than lumbar enlargement, while the proportion labelled from dorsal medulla is similar in the two regions. We also found that lamina I cells in L4 that project to the dorsal medulla are included in the population retrogradely labelled from LPb, thus confirming the estimate that there are around 400 lamina I projection cells in this segment.

Polgar, Erika; Wright, Lorna L.; Todd, Andrew J.

2010-01-01

111

A quantitative study of brainstem projections from lamina I neurons in the cervical and lumbar enlargement of the rat.  

PubMed

Lamina I of the rat spinal cord contains neurons that project to various brain areas including thalamus, periaqueductal grey matter (PAG), lateral parabrachial area (LPb), caudal ventrolateral medulla and a region in dorsal medulla that includes the nucleus tractus solitarius and dorsal reticular nucleus. We have shown that spinothalamic lamina I neurons are infrequent in rat lumbar enlargement, where they constitute approximately 5% of the estimated 400 projection neurons on each side of the L4 segment (Al-Khater and Todd, 2009). They are more numerous in cervical enlargement, but the total number of lamina I projection neurons in this region was not known. Here we have used paired injections of retrograde tracers into the brainstem to estimate the number of lamina I projection cells in the C7 segment. Our results suggest that there are approximately 215 lamina I projection cells per side, and that spinothalamic cells therefore make up approximately 42% of this population. The proportion of lamina I projection neurons labelled from PAG is higher in cervical than lumbar enlargement, while the proportion labelled from dorsal medulla is similar in the two regions. We also found that lamina I cells in L4 that project to the dorsal medulla are included in the population retrogradely labelled from LPb, thus confirming the estimate that there are around 400 lamina I projection cells in this segment. PMID:19854164

Polgár, Erika; Wright, Lorna L; Todd, Andrew J

2009-10-23

112

The nuclear lamina and its proposed roles in tumorigenesis: Projection on the hematologic malignancies and future targeted therapy  

Microsoft Academic Search

The nuclear lamina, a network of lamin filaments and lamin-associated proteins, is located between the inner nuclear membrane and the peripheral chromatin. The nuclear lamina is involved in numerous nuclear functions including maintaining nuclear shape, determining nuclear positioning, organizing chromatin and regulating the cell cycle, DNA replication, transcription, cell differentiation, apoptosis, and aging. Alterations in the composition of nuclear lamins

Miron Prokocimer; Ayelet Margalit; Yosef Gruenbaum

2006-01-01

113

Differential global and extra-cellular matrix focused gene expression patterns between normal and glaucomatous human lamina cribrosa cells  

Microsoft Academic Search

Purpose: Marked extracellular matrix (ECM) remodeling occurs in the human optic nerve head in primary open angle glaucoma (POAG). The glial fibrillary acid protein (GFAP) negative lamina cribrosa cell may play an important role in this remodeling process. We report the first study of global and ECM-focused gene transcription differentials between GFAP-negative lamina cribrosa (LC) cells from normal and POAG

Ruaidhrí P. Kirwan; Robert J. Wordinger; Abbot F. Clark; Colm J. O'Brien

2009-01-01

114

Three-Dimensional Architecture of the Subepithelial Connective Tissue in the Omasal Laminae of Sheep and Cattle  

Microsoft Academic Search

The three-dimensional architecture of the subepithelial connective tissue in the omasal laminae of sheep and cattle was studied by scanning electron microscopy after treatment with 2 N NaOH solution. The omasal laminae were equipped with highly undulated subepithelial connective tissue showing various projections or ridges. In the sheep, the subepithelial connective tissue in the omasal papillae formed flat papillary projections

Y. Yamamoto; N. Kitamura; J. Yamada; T. Yamashita

1993-01-01

115

Basal lamina heparan sulphate proteoglycan is involved in otic placode invagination in chick embryos.  

PubMed

Formation of the otocyst from the otic placode appears to differ from invagination of other cup-shaped organ primordia. It is known that the cellular cytoskeleton plays a limited role in otic placode invagination, whilst the extracellular matrix underlying the otic primordium intervenes in the folding process. In this study we have analysed the role of the basal lamina heparan sulphate proteoglycan in otic primordium invagination. At 10 H.H. stage, heparan sulphate proteoglycan immunomarking begins to appear on the otic placode basal lamina, increasing noticeably at 13 H.H. stage, coinciding with maximum folding of the otic epithelium, and is still present at later stages. Enzyme degradation of heparan sulphate proteoglycan in the otic primordium basal lamina, by means of microinjection with heparinase III prior to folding, significantly disrupts invagination of the otic placode, which remains practically flat, with a significant reduction in the depth of the otic pit and an increase in the diameter of the otic opening. The immunocytochemistry analysis revealed a notable depletion of basal lamina heparan sulphate proteoglycan in the otic primordia microinjected with heparinase, with no statistically significant differences observed in the volume or rate of cell proliferation in the otic epithelium relative to the control, which suggests that heparan sulphate proteoglycan disruption does not interfere with the epithelial growth. In addition, a study of apoptosis distribution by the TUNEL method confirmed that treatment with heparinase does not cause interference with cell survival in the otic epithelium. Our findings support the theory that otic primordium invagination may be regulated, at least in part, by the basal lamina components, which might contribute towards anchoring the otic epithelium to adjacent structures. PMID:11000284

Moro-Balbás, J A; Gato, A; Alonso, M I; Martín, P; de la Mano, A

2000-10-01

116

Alien Invasion  

NSDL National Science Digital Library

In this activity students will work in teams to investigate the impact of an invasive species on native species, using the six classic steps for solving environmental problems. Teams will research a local invasive species problem, complete an experimental design plan, write clear procedures for experimentation, state expected results and conclusions, and work together to determine the course of action to be taken and future monitoring needs. Teams will present their action plan to a simulated board of review through a formal presentation. While completing this activity students will learn to create a workable experimental design, create clear experimental procedures, and practice peer review.

Maben, Ann

117

Globular and asymmetric acetylcholinesterase in the synaptic basal lamina of skeletal muscle  

PubMed Central

The aim of this study was to characterize the molecular forms of acetylcholinesterase (AChE) associated with the synaptic basal lamina at the neuromuscular junction. The observations were made on the neuromuscular junctions of cutaneous pectoris muscles of frog, Rana pipiens, which are similar to junctions of most other vertebrates including mammals, but are especially convenient for experimentation. By measuring relative AChE activity in junctional and extrajunctional regions of muscles after selective inactivation of extracellular AChE with echothiophate, or of intracellular AChE with DFP and 2-PAM, we found that > 66% of the total AChE activity in the muscle was junction- specific, and that > 50% of the junction-specific AChE was on the cell surface. More than 80% of the cell surface AChE was solubilized in high ionic strength detergent-free buffer, indicating that most, if not all, was a component of the synaptic basal lamina. Sedimentation analysis of that fraction indicated that while asymmetric forms (A12, A8) were abundant, globular forms sedimenting at 4-6 S (G1 and G2), composed > 50% of the AChE. It was also found that when muscles were damaged in various ways that caused degeneration of axons and muscle fibers but left intact the basal lamina sheaths, the small globular forms persisted at the synaptic site for weeks after phagocytosis of cellular components; under certain damage conditions, the proportion of globular to asymmetric forms in the vacated basal lamina sheaths was as in normal junctions. While the asymmetric forms required high ionic strength for solubilization, the extracellular globular AChE could be extracted from the junctional regions of normal and damaged muscles by isotonic buffer. Some of the globular AChE appeared to be amphiphilic when examined in detergents, suggesting that it may form hydrophobic interactions, but most was non-amphiphilic consistent with the possibility that it forms weak electrostatic interactions. We conclude that the major form of AChE in frog synaptic basal lamina is globular and that its mode of association with the basal lamina differs from that of the asymmetric forms.

1994-01-01

118

Cultured incisors display major modifications in basal lamina deposition without further effect on odontoblast differentiation  

Microsoft Academic Search

Matrix-mediated epithelio-mesenchymal interactions play a crucial role in the control of dental cytodifferentiations. Ultrastructural observation of the epithelio-mesenchymal junction in cultured embryonic mouse molars showed discrete zones with duplicated or multilayered basal laminae. The use of synthetic peptides demonstrated that the process was RGD*-independent, did not involve the YIGSR* sequence present on laminin and could occur spontaneously. Cultured incisors showed

Jean-Marie Meyer; Jean Victor Ruch; Marie Dominique Kubler; Christian Kupferle; Hervé Lesot

1995-01-01

119

Molecular Maps of the Reorganization of Genome-Nuclear Lamina Interactions during Differentiation  

Microsoft Academic Search

The three-dimensional organization of chromosomes within the nucleus and its dynamics during differentiation are largely unknown. To visualize this process in molecular detail, we generated high-resolution maps of genome-nuclear lamina interactions during subsequent differentiation of mouse embryonic stem cells via lineage-committed neural precursor cells into terminally differentiated astrocytes. This reveals that a basal chromosome architecture present in embryonic stem cells

Daan Peric-Hupkes; Wouter Meuleman; Ludo Pagie; Sophia W. M. Bruggeman; Irina Solovei; Wim Brugman; Stefan Gräf; Paul Flicek; Ron M. Kerkhoven; Maarten van Lohuizen; Marcel Reinders; Lodewyk Wessels; Bas van Steensel

2010-01-01

120

Metal effects on soil invertebrate feeding: measurements using the bait lamina method.  

PubMed

Heightened concerns regarding the protection of terrestrial ecosystems at a national level has increased the need to develop a suite of indicators capable of assessing the quality, integrity and fertility of soils. Of the assays currently available, tests that measure aspects of soil function and associated parameters are among the most promising, since these integrate effects on soil quality at the highest level of organisation. In this study we describe results of the deployment of an indicator of soil functional integrity (the bait lamina test) that is designed to measure the feeding activity of soil invertebrates. Bait lamina was used at six grassland sites located along a transect from a smelter at Avonmouth (South-West England) used in the EU funded BIOPRINT II project. Results indicated highest bait removal (feeding) at sites furthest from the factory, intermediate feeding activity at intervening sites and extremely low activities at the two sites closest to the smelter. The strong decline in activity for the group of sites closest to the smelter corresponded with increasing metal concentrations suggesting a clear impact of metals on detritivorous invertebrate feeding. Comparisons of the results of the bait lamina study to previous invertebrate survey work suggested that the differences in observed bait removal can be attributed to direct effects of metals on the abundance and biodiversity of key decomposer groups such as earthworms, isopods, molluscs, myriapods, springtails and mites. PMID:15736851

Filzek, Petra D B; Spurgeon, David J; Broll, Gabriele; Svendsen, Claus; Hankard, Peter K; Parekh, Nisha; Stubberud, Hege E; Weeks, Jason M

2004-11-01

121

[Study on the modeling of hyperspectral polarized reflection of clove lamina with chlorophyll content].  

PubMed

In the present study, the authors detected clove laminas in different states with multi-angle hyperspectral polarized reflections and measured their chlorophyll content at the same time. The authors analyzed hyperspectral polarized reflections of clove laminas from various viewing zenith angles, incidence angles, the relative azimuth angles, polarized states and chlorophyll content. The authors calculated quantitatively clove laminas in different states with multi-angle hyperspectral polarized reflection by USB2000, bidirectional polarized reflectance and polarized equipment, and built the regression models of polarized information-chlorophyll content. The result indicated that when the polarized angle was 0 degrees, the model of chlorophyll content with polarization reflectance was built as Y = 4. 506 4e(-0.56 8x) (R2 = 0.895 8); while as the polarized angle was 90 degrees, the model of chlorophyll content with polarization reflectance was built as Y = 145.79X(-1.204 1)(R2 = 0.479 8); when the incidence angle was 50 degrees, the model of chlorophyll content with degree of polarization was built as Y = 7 206.7X(6) -20 160 X(5) + 22 547X(4)-12 788X(5) + 3 822.4X(2) -553.72X + 30.429 (R2 = 0.646 4). The authors found that a significant functional relationship between the polarized information and chlorophyll content exists. The study provides a theoretical base for vegetation remote sensing. PMID:19810539

Han, Yang; Zhao, Yun-Sheng; Zhang, Li-Li; Lü, Yun-Feng

2009-06-01

122

Insights into the structure and composition of the peritubular dentin organic matrix and the lamina limitans.  

PubMed

Dentin is a mineralized dental tissue underlying the outer enamel that has a peculiar micro morphology. It is composed of micrometer sized tubules that are surrounded by a highly mineralized structure, called peritubular dentin (PTD), and embedded in a collagen-rich matrix, named intertubular dentin. The PTD has been thought to be composed of a highly mineralized collagen-free organic matrix with unknown composition. Here we tested the hypothesis that proteoglycans and glycosaminoglycans, two important organic structural features found in dentin, are key participants in the microstructure and composition of the PTD. To test this hypothesis dentin blocks were demineralized with 10 vol% citric acid for 2 min and either digested with 1mg/ml TPCK-treated trypsin with 0.2 ammonium bicarbonate at pH 7.9 (TRY) or 0.1 U/mL C-ABC with 50mM Tris, 60mM sodium acetate and 0.02% bovine serum albumin at pH 8.0 (C-ABC). TRY is known to cleave the protein core of dentin proteoglycans, whereas C-ABC is expected to selectively remove glycosaminoglycans. All specimens were digested for 48 h in 37°C, dehydrated in ascending grades of acetone, immersed in HMDS, platinum coated and imaged using an FE-SEM. Images of demineralized dentin revealed a meshwork of noncollagenous fibrils protruding towards the tubule lumen following removal of the peritubular mineral and confirmed the lack of collagen in the peritubular matrix. Further, images revealed that the peritubular organic network originates from a sheet-like membrane covering the entire visible length of tubule, called lamina limitans. Confirming our initial hypothesis, after the digestion with C-ABC the organic network appeared to vanish, while the lamina limitans was preserved. This suggests that glycosaminoglycans are the main component of the PTD organic network. Following digestion with TRY, both the organic network and the lamina limitans disappeared, thus suggesting that the lamina limitans may be primarily composed of proteoglycan protein cores. In summary, our results provide novel evidence that (1) PTD lacks collagen fibrils, (2) PTD contains an organic scaffold embedded with mineral and (3) the PTD organic matrix is manly composed of glycosaminoglycans, whereas the lamina limitans is primarily made of proteoglycans protein cores. PMID:21890367

Bertassoni, Luiz Eduardo; Stankoska, Katerina; Swain, Michael Vincent

2011-08-12

123

Invasive Species  

NSDL National Science Digital Library

The Advanced Technology Environmental and Energy Center (ATEEC) presents this group of documents on invasive species. The materials include a webquest, an informational flyer, service standards, National Science Education Standards, and a guide for creating public service announcements. The materials are supplied in PDF format and would be useful for biology or ecology teachers. Users must download this resource for viewing, which requires a free log-in. There is no cost to download the item.

2011-02-11

124

Expression of AMPA receptor subunits at synapses in laminae I-III of the rodent spinal dorsal horn  

PubMed Central

Background Glutamate receptors of the AMPA type (AMPArs) mediate fast excitatory transmission in the dorsal horn and are thought to underlie perception of both acute and chronic pain. They are tetrameric structures made up from 4 subunits (GluR1-4), and subunit composition determines properties of the receptor. Antigen retrieval with pepsin can be used to reveal the receptors with immunocytochemistry, and in this study we have investigated the subunit composition at synapses within laminae I–III of the dorsal horn. In addition, we have compared staining of AMPArs with that for PSD-95, a major constituent of glutamatergic synapses. We also examined tissue from knock-out mice to confirm the validity of the immunostaining. Results As we have shown previously, virtually all AMPAr-immunoreactive puncta were immunostained for GluR2. In laminae I–II, ~65% were GluR1-positive and ~60% were GluR3-positive, while in lamina III the corresponding values were 34% (GluR1) and 80% (GluR3). Puncta stained with antibody against the C-terminus of GluR4 (which only detects the long form of this subunit) made up 23% of the AMPAr-containing puncta in lamina I, ~8% of those in lamina II and 46% of those in lamina III. Some overlap between GluR1 and GluR3 was seen in each region, but in lamina I GluR1 and GluR4 were present in largely non-overlapping populations. The GluR4 puncta often appeared to outline dendrites of individual neurons in the superficial laminae. Virtually all of the AMPAr-positive puncta were immunostained for PSD-95, and 98% of PSD-95 puncta contained AMPAr-immunoreactivity. Staining for GluR1, GluR2 and GluR3 was absent in sections from mice in which these subunits had been knocked out, while the punctate staining for PSD-95 was absent in mice with a mutation that prevents accumulation of PSD-95 at synapses. Conclusion Our results suggest that virtually all glutamatergic synapses in laminae I–III of adult rat spinal cord contain AMPArs. They show that synapses in laminae I–II contain GluR2 together with GluR1 and/or GluR3, while the long form of GluR4 is restricted to specific neuronal populations, which may include some lamina I projection cells. They also provide further evidence that immunostaining for AMPAr subunits following antigen retrieval is a reliable method for detecting these receptors at glutamatergic synapses.

Polgar, Erika; Watanabe, Masahiko; Hartmann, Bettina; Grant, Seth GN; Todd, Andrew J

2008-01-01

125

Significance of host cell kinases in herpes simplex virus type 1 egress and lamin-associated protein disassembly from the nuclear lamina  

SciTech Connect

The nuclear lamina is thought to be a steric barrier to the herpesvirus capsid. Disruption of the lamina accompanied by phosphorylation of lamina proteins is a conserved feature of herpesvirus infection. In HSV-1-infected cells, protein kinase C (PKC) alpha and delta isoforms are recruited to the nuclear membrane and PKC delta has been implicated in phosphorylation of emerin and lamin B. We tested two critical hypotheses about the mechanism and significance of lamina disruption. First, we show that chemical inhibition of all PKC isoforms reduced viral growth five-fold and inhibited capsid egress from the nucleus. However, specific inhibition of either conventional PKCs or PKC delta does not inhibit viral growth. Second, we show hyperphosphorylation of emerin by viral and cellular kinases is required for its disassociation from the lamina. These data support hypothesis that phosphorylation of lamina components mediates lamina disruption during HSV nuclear egress.

Leach, Natalie R. [Program in Molecular and Cellular Biology, University of Iowa, Iowa City, IA 52242 (United States); Roller, Richard J., E-mail: richard-roller@uiowa.ed [Department of Microbiology, University of Iowa, Iowa City, IA 52242 (United States)

2010-10-10

126

Significance of host cell kinases in herpes simplex virus type 1 egress and lamin-associated protein disassembly from the nuclear lamina  

PubMed Central

The nuclear lamina is thought to be a steric barrier to the herpesvirus capsid. Disruption of the lamina accompanied by phosphorylation of lamina proteins is a conserved feature of herpesvirus infection. In HSV-1-infected cells, protein kinase C (PKC) alpha and delta isoforms are recruited to the nuclear membrane and PKC delta has been implicated in phosphorylation of emerin and lamin B. We tested two critical hypotheses about the mechanism and significance of lamina disruption. First, we show that chemical inhibition of all PKC isoforms reduced viral growth five-fold and inhibited capsid egress from the nucleus. However, specific inhibition of either conventional PKCs or PKC delta does not inhibit viral growth. Second, we show hyperphosphorylation of emerin by viral and cellular kinases is required for its disassociation from the lamina. These data support hypothesis that phosphorylation of lamina components mediates lamina disruption during HSV nuclear egress.

Leach, Natalie R.; Roller, Richard J.

2010-01-01

127

Differentiation of axon-related Schwann cells in vitro. I. Ascorbic acid regulates basal lamina assembly and myelin formation  

PubMed Central

Rat Schwann cells cultured with dorsal root ganglion neurons in a serum- free defined medium fail to ensheathe or myelinate axons or assemble basal laminae. Replacement of defined medium with medium that contains human placental serum (HPS) and chick embryo extract (EE) results in both basal lamina and myelin formation. In the present study, the individual effects of HPS and EE on basal lamina assembly and on myelin formation by Schwann cells cultured with neurons have been examined. Some batches of HPS were unable to promote myelin formation in the absence of EE, as assessed by quantitative evaluation of cultures stained with Sudan black; such HPS also failed to promote basal lamina assembly, as assessed by immunofluorescence using antibodies against laminin, type IV collagen, and heparan sulfate proteoglycan. The addition of EE or L-ascorbic acid with such HPS led to the formation of large quantities of myelin and to the assembly of basal laminae. Pretreatment of EE with ascorbic acid oxidase abolished the EE activity, whereas trypsin did not. Other batches of HPS were found to promote both basal lamina and myelin formation in the absence of either EE or ascorbic acid. Ascorbic acid oxidase treatment or dialysis of these batches of HPS abolished their ability to promote Schwann cell differentiation, whereas the subsequent addition of ascorbic acid restored that ability. Ascorbic acid in the absence of serum was relatively ineffective in promoting either basal lamina or myelin formation. Fetal bovine serum was as effective as HPS in allowing ascorbic acid (and several analogs but not other reducing agents) to manifest its ability to promote Schwann cell differentiation. We suggest that ascorbic acid promotes Schwann cell myelin formation by enabling the Schwann cell to assemble a basal lamina, which is required for complete differentiation.

1987-01-01

128

Neurotransmitters alter the numbers of synapses and organelles in photoreceptor terminals in the lamina of the housefly, Musca domestica  

Microsoft Academic Search

Various organelles in the lamina terminals of housefly photoreceptors exhibit daily rhythms having a circadian basis. These\\u000a include changes in the numbers of photoreceptor tetrad and L2 feedback synapses, and longitudinal movements of screening pigment.\\u000a Circadian information has previously been suggested to spread from the clock to the lamina via widefield cells expressing\\u000a either 5-hydroxytryptamine or pigment-dispersing hormone-like immunoreactivity. We

E. Pyza; I. A. Meinertzhagen

1998-01-01

129

Non-peptidergic primary afferents are presynaptic to neurokinin-1 receptor immunoreactive lamina I projection neurons in rat spinal cord  

PubMed Central

Background Pain-related (nociceptive) information is carried from the periphery to the dorsal horn of the spinal cord mostly by two populations of small diameter primary afferents, the peptidergic and the non-peptidergic. The peptidergic population expresses neuropeptides, such as substance P and calcitonin gene-related peptide, while the non-peptidergic fibers are devoid of neuropeptides, express the purinergic receptor P2X3, and bind the isolectin B4 (IB4). Although it has been known for some time that in rat the peptidergic afferents terminate mostly in lamina I and outer lamina II and non-peptidergic afferents in inner lamina II, the extent of the termination of the latter population in lamina I was never investigated as it was considered as very minor. Because our preliminary evidence suggested otherwise, we decided to re-examine the termination of non-peptidergic afferents in lamina I, in particular with regards to their innervation of projection neurons expressing substance P receptors (NK-1r). We used retrograde labeling of neurons from the parabrachial nucleus combined with lectin IB4 binding and immunocytochemistry. Samples were examined by confocal and electron microscopy. Results By confocal microscopy, we studied the termination of non-peptidergic afferents in lamina I using IB4 binding and P2X3 immunoreactivity as markers, in relation to CGRP immunoreactivy, a marker of peptidergic afferents. The number of IB4 or P2X3-labeled fibers in lamina I was higher than previously thought, although they were less abundant than CGRP-labeled afferents. There were very few fibers double-labeled for CGRP and either P2X3 or IB4. We found a considerable number of IB4-positive fiber varicosities in close apposition to NK-1r-positive lamina I projection neurons, which were distinct from peptidergic varicosities. Furthermore, we confirmed at the ultrastructural level that there were bona fide synapses between P2X3-immunoreactive non-peptidergic boutons and neurokinin-1 receptor-positive lamina I dendrites. Conclusions These results indicate the presence of direct innervation by non-peptidergic nociceptive afferents of lamina I projection neurons expressing NK-1r. Further investigations are needed to better understand the role of these connections in physiological conditions and chronic pain states.

2012-01-01

130

Chronic laminitis is associated with potential bacterial pathogens in the laminae.  

PubMed

A common sequella of chronic laminitis in horses is repeated abscesses with variable lameness and drainage. It is unclear whether the exudate represents the debridement phase of a non-septic inflammatory process involving clearance of laminar tissue damaged during the acute episode of laminitis, or a response to a microbial infection developed by ascent of microbes from the environment to the tissue via the white line. The objective of this study was to evaluate the possibility that an undiagnosed microbial infection in laminar tissue is present in laminar tissue collected from chronically laminitic horses without an active hoof abscess. Methods to collect laminar tissue, aseptically, from control (non-laminitic) horses and those with chronic/recurrent laminitis are described. Laminae homogenates were evaluated for the presence of bacteria. Bacteria were identified using biochemical tests and sequencing of 16S rRNA and virulence genes. Laminae from chronically laminitic horses revealed 100-fold higher levels (P=0.002) of bacteria compared to control, non-laminitic horses. Although environmental organisms were identified, potential pathogens were identified. Included were Gram positive bacteria, Brevibacterium luteolum, coagulase-negative Staphylococcus spp. as well as Gram negative bacteria, enterohemorrhagic Escherichia coli and Alcaligenes faecalis. Further research is warranted to evaluate the role of bacteria in equine chronic laminitis. PMID:22410310

Onishi, Janet C; Park, Joong-Wook; Häggblom, Max M; Fennell, Michael J; Fugaro, Michael N

2012-02-21

131

Electromechanical characterization of a single active structural fiber lamina for multifunctional composites  

NASA Astrophysics Data System (ADS)

Piezoelectric fiber composites (PFCs) are a new group of materials recently developed in order to overcome the fragile nature of monolithic piezoceramics. However, there are some practical limitations associated with these types of materials, namely the generally separate electrode makes them difficult to embed into composites and when imbedded the low tensile properties of the material and the abnormal geometry in comparison with traditional reinforcements lead to stress concentrations reducing the material's strength. To resolve the inadequacies of current PFCs, a novel active structural fiber (ASF) was developed that can be embedded in a composite material to perform sensing and actuation, in addition to providing load bearing functionality. The ASF combines the advantages of the high tensile modulus and strength of the traditional composite reinforcements as well as the sensing and actuation properties of piezoceramic materials. A micromechanics model based on the double inclusion approach and a finite element model were been developed to study the effective piezoelectric coupling coefficient of the ASF as well as the ASF lamina. In order to evaluate the performance of the ASF when embedded in a polymer matrix and validate the model's accuracy, single fiber lamina have been fabricated and characterized through testing with an atomic force microscope. The results of our testing demonstrate the accuracy of the model and show that ASF composites could lead to load bearing composites with electromechanical coupling greater than most pure piezoelectric materials.

Lin, Yirong; Sodano, Henry A.

2009-03-01

132

Changes in lamina structure are followed by spatial reorganization of heterochromatic regions in caspase-8-activated human mesenchymal stem cells.  

PubMed

Apoptosis is fundamental to the regulation of homeostasis of stem cells in vivo. Whereas the pathways underlying the molecular and biochemical details of nuclear breakdown that accompanies apoptosis have been elucidated, the precise nature of nuclear reorganization that precedes the demolition phase is not fully understood. Here, we expressed an inducible caspase-8 in human mesenchymal stem cells, and quantitatively followed the early changes in nuclear organization during apoptosis. We found that caspase-8 induces alteration of the nuclear lamina and a subsequent spatial reorganization of both centromeres, which are shifted towards a peripheral localization, and telomeres, which form aggregates. This nuclear reorganization correlates with caspase-3 sensitivity of lamina proteins, because the expression of lamin mutant constructs with caspase-3 hypersensitivity resulted in a caspase-8-independent appearance of lamina intranuclear structures and telomere aggregates, whereas application of a caspase inhibitor restrains these changes in nuclear reorganization. Notably, upon activation of apoptosis, we observed no initial changes in the spatial organization of the promyelocytic leukemia nuclear bodies (PML-NBs). We suggest that during activation of the caspase-8 pathway changes in the lamina structure precede changes in heterochromatin spatial organization, and the subsequent breakdown of lamina and PML-NB. PMID:17003109

Raz, Vered; Carlotti, Françoise; Vermolen, Bart J; van der Poel, Egge; Sloos, Willem C R; Knaän-Shanzer, Shoshan; de Vries, Antoine A F; Hoeben, Rob C; Young, Ian T; Tanke, Hans J; Garini, Yuval; Dirks, Roeland W

2006-09-26

133

Fine structural organization of spinothalamic and trigeminothalamic lamina I terminations in the nucleus submedius of the cat.  

PubMed

We examined lamina I trigemino- and spinothalamic tract (TSTT) terminals labeled with Phaseolus vulgaris leucoagglutinin in the nucleus submedius (Sm), a nociceptive relay in the cat's thalamus. Volume-rendered (three-dimensional) reconstructions of ten lamina I TSTT terminals identified with light and electron microscopy were built from serial ultrathin sections by computer, which enabled the overall structures of the terminal complexes to be characterized in detail. Two fundamentally different terminations were observed: compact clusters of numerous boutons, which predominate in the dense focus of a lamina I terminal field in the Sm, and boutons-of-passage, which are present throughout the terminal field and predominate in its periphery. Reconstructions of cluster terminations reveal that all boutons of each cluster make synaptic contact with protrusions and branch points on a single dendrite and involve presynaptic dendrites (PSDs) in triadic arrangements, providing a basis for the secure relay of sensory information. In contrast, reconstructions show that boutons-of-passage are generally characterized by simple contacts with PSDs, indicating an ascending inhibitory lamina I influence. These different synaptic arrangements are consistent with physiological evidence indicating that the morphologically distinct nociceptive-specific and thermoreceptive-(cold)-specific lamina I TSTT neurons terminate differently within the Sm. Thus, a suitable structural substrate exists in the cat's Sm for the inhibitory effect of cold on nociception, a behavioral and physiological phenomenon of fundamental significance. We conclude that the Sm is more than a simple relay for nociception, and that it may be an integrative comparator of ascending modality-selective information that arrives from neurons in lamina I. PMID:8841905

Ericson, A C; Blomqvist, A; Krout, K; Craig, A D

1996-08-01

134

Invasive amebiasis.  

PubMed

Digestive amoebiasis with his invasive form is an unusual pathology encountered in the temperate zone. This could lead to a life threatening complication: systemic amoebiasis. A 55-year-old male was treated successfully of systemic amoebiasis in a third referral hospital. The diagnosis was established based on epidemiology data and microscopical identification of trophozoites of Entamoeba histolytica. The amoebicidal, antibiotic and supportive treatments was firstly administrated. The clinical picture of intestinal amoebiasis raised from dysenteric syndrome to necrotizing enteritis. The bowel perforation with localized peritonitis was followed by chronic enteric fistula. Amoebic liver abscess, as the most frequent extraintestinal complication, was concomitantly diagnosed and treated. Urinary amoebiasis was considered as complication in the context of systemic dissemination: any other location could become a site of an amoebic abscess. Multidisciplinary approach was the successful key in the management of the patient, including antiparasitic therapy and antibiotic prophylaxis, intensive care and multiple surgical approaches. The diagnosis of digestive amoebiasis and systemic complication may be delayed in nonendemic areas, leading to advanced and complicated stages of the disease. The surgical approach is most efficiently to treat a large liver amoebic abscess and intraperitoneal collections. PMID:17278650

Grecu, F; Bulgariu, Teodora; Blanaru, Oana; Dragomir, C; Lunca, Claudia; Stratan, I; Manciuc, Carmen; Luca, V

135

The bone lamina technique: a novel approach for lateral ridge augmentation--a case series.  

PubMed

The goal of this case series is to present a novel treatment approach for lateral ridge augmentation. Four systemically healthy patients (aged 48 to 59 years) with inadequate dental alveolar ridge widths were selected for inclusion. All ridge defects were augmented using a xenogeneic cortical bone shield in combination with particulated bone substitutes and a thin collagen barrier. At baseline and after 6 months, digital cone beam computed tomography scans were performed. Biopsy specimens were harvested at reentry surgery and processed for histologic analysis. The results revealed a sufficient amount of bone structure for implant placement without additional augmentation procedures. The histologic analysis demonstrated that new bone formation had taken place and the bone shield had resorbed entirely. This case series indicates that the bone lamina technique has the biologic and mechanical properties to successfully achieve hard tissue augmentation of deficient ridges. PMID:23820709

Wachtel, Hannes; Fickl, Stefan; Hinze, Marc; Bolz, Wolfgang; Thalmair, Tobias

136

[Morphological study of Organum cavum pre-lamina terminalis (OCPLT), implicated in thirst in rats].  

PubMed

It has been shown that micro-injections of angiotensin II in the Organum cavum pre-lamina terminalis (OCPLT) of the rat brain trigger water intake. Our anatomical study shows that the anterior, vertical extension of this Organum corresponds to the anterior inter-hemispheric fissure, and its posterior, horizontal extension to the Cavum septi pellucidi (CSP). Contrary to classical descriptions, the CSP persists in the adult rat, though reduced to one third of its initial antero-posterior extension. It appears rostrally as an opening into the anterior inter-hemispheric fissure. The absence of ependymal cells and of communication with the lateral ventricles points to the fact that this diverticulum is not a median cerebral ventricle. Its pial sheathing and the presence of leptomenix in the cavity confirm its inter-hemispheric origin. The pinocytotic vesicles of the meningeal capillaries suggest an active transfer of substances. Circumstantial evidence suggests circulating angiotensin could be one of them. PMID:9247028

Ronsin, E; Perre, J

1997-06-01

137

Optical seeing-mechanism of formation of thin turbulent laminae in the atmosphere.  

PubMed

Data from balloon soundings taken at sites in the Canary Islands, France, and Chile are used to show that hydrodynamic instability, perhaps engendered by the propagation of buoyancy (gravity) or other waves, leads to the formation of thin, turbulent laminae, or "seeing layers." These seeing layers occur almost invariably in pairs and exhibit large values for the temperature-structure coefficient C(T)(2) because they form where the gradient of temperature is particularly steep. The refractive-index-structure coefficient is correspondingly large, and so these layers adversely affect the quality of optical propagation. The mechanism proposed here is already known to create clear air turbulence in the stratosphere, and we show how it is consistent with the formation of thin turbulent seeing layers in the troposphere and the stratosphere at night, when the atmosphere is generally stably stratified. PMID:21060368

Coulman, C E; Vernin, J; Fuchs, A

1995-08-20

138

The lamina cribrosa and visual field defects in open-angle glaucoma.  

PubMed

Two types of lamina cribrosa, one with the classic dot-like openings and the other with striate openings, were seen in 71 pairs of optic disc photographs from patients who had chronic open-angle glaucoma, were suspected to have glaucoma or had normal eyes. Of the 11 eyes with a striate pattern 64% showed glaucomatous visual field defects, whereas of the 60 eyes with a dot pattern only 12% showed such defects, a highly significant difference (p less than 0.001); when patient age and ratio of the vertical diameters of the optic cup and disc were controlled the difference remained significant (p = 0.0402). The striate pattern was also significantly associated (p less than 0.05) with a large optic cup (vertical cup/disc ratio 0.7 or greater). PMID:6871789

Susanna, R

1983-04-01

139

An accurate and reproducible method for proteome profiling of the effects of salt stress in the rice leaf lamina  

Microsoft Academic Search

Proteomic analysis of any biological system by two- dimensional gel electrophoresis (2-DE) requires high resolution and high reproducibility. The results pre- sented here demonstrate the reproducible and accu- rate separation of rice (Oryza sativa L.) proteins using improved procedures for high resolution 2-DE, which were adapted for the separation of rice lamina proteins. Validation of this system was achieved by

Robert Parker; Timothy J. Flowers; Anthony L. Moore; Nicholas V. J. Harpham

2006-01-01

140

The development of the reticular lamina in the hamster: An examination of transitory features and their functional roles  

Microsoft Academic Search

This study examines the development of the reticular lamina in the Syrian golden hamster postriatally from birth to adulthood at 2 day intervals using the scanning electron microscope. During this period, numerous transitory features emerged whose roles were concerned primarily with the development of the tectorial membrane (TM). The principal findings were as follows. (1) The surface of the developing

James A Kaltenbach; Pamela R Falzarano

1997-01-01

141

Viral Mimicry of Cdc2/Cyclin-Dependent Kinase 1 Mediates Disruption of Nuclear Lamina during Human Cytomegalovirus Nuclear Egress  

PubMed Central

The nuclear lamina is a major obstacle encountered by herpesvirus nucleocapsids in their passage from the nucleus to the cytoplasm (nuclear egress). We found that the human cytomegalovirus (HCMV)-encoded protein kinase UL97, which is required for efficient nuclear egress, phosphorylates the nuclear lamina component lamin A/C in vitro on sites targeted by Cdc2/cyclin-dependent kinase 1, the enzyme that is responsible for breaking down the nuclear lamina during mitosis. Quantitative mass spectrometry analyses, comparing lamin A/C isolated from cells infected with viruses either expressing or lacking UL97 activity, revealed UL97-dependent phosphorylation of lamin A/C on the serine at residue 22 (Ser22). Transient treatment of HCMV-infected cells with maribavir, an inhibitor of UL97 kinase activity, reduced lamin A/C phosphorylation by approximately 50%, consistent with UL97 directly phosphorylating lamin A/C during HCMV replication. Phosphorylation of lamin A/C during viral replication was accompanied by changes in the shape of the nucleus, as well as thinning, invaginations, and discrete breaks in the nuclear lamina, all of which required UL97 activity. As Ser22 is a phosphorylation site of particularly strong relevance for lamin A/C disassembly, our data support a model wherein viral mimicry of a mitotic host cell kinase activity promotes nuclear egress while accommodating viral arrest of the cell cycle.

Ndassa-Colday, Yasmine M.; Lin, Alison J.; Jahng, Wan Jin; Baek, Moon-Chang; Noton, Sarah; Silva, Laurie A.; Simpson-Holley, Martha; Knipe, David M.; Golan, David E.; Marto, Jarrod A.; Coen, Donald M.

2009-01-01

142

Multi-scale Rule-of-Mixtures Model of Carbon Nanotube/Carbon Fiber/Epoxy Lamina.  

National Technical Information Service (NTIS)

A unidirectional carbon fiber/epoxy lamina in which the carbon fibers are coated with single-walled carbon nanotubes is modeled with a multi-scale method, the atomistically informed rule-of-mixtures. This multi-scale model is designed to include the effec...

S. J. V. Frankland J. C. Roddick T. S. Gates

2005-01-01

143

Statistics of fracture for an elastic notched composite lamina containing weibull fibers—Part II. Probability models of crack growth  

Microsoft Academic Search

Analytical probability models and useful approximations are developed to study the effects of statistical variation in fiber strength on the statistics of the fracture process, fracture resistance, and overall strength distribution for an elastic composite lamina with a transverse notch of N contiguous broken fibers (0 ? N ? 51). In Part I, we generated representative fracture strength distributions with

Irene J. Beyerlein; S. Leigh Phoenix

1997-01-01

144

Aging is associated with increased collagen type IV accumulation in the basal lamina of human cerebral microvessels  

Microsoft Academic Search

BACKGROUND: Microvascular alterations contribute to the development of stroke and vascular dementia. The goal of this study was to evaluate age and hypertension related changes of the basal lamina in cerebral microvessels of individuals, who died from non-cerebral causes. RESULTS: We examined 27 human brains: 11 young and 16 old patients. Old patients were divided into two subgroups, those with

Olga Uspenskaia; Martin Liebetrau; Jochen Herms; Adrian Danek; Gerhard F Hamann

2004-01-01

145

Partial cleavage of A-type lamins concurs with their total disintegration from the nuclear lamina during apoptosis  

Microsoft Academic Search

Apoptosis ± Lamin ± caspase 6 ± cleavage Although activated caspase 6 is capable of cleaving both A- and B-type lamins during apoptosis, the higher-order structure of the nuclear lamina may cause a differential breakdown of these two types of lamins. In order to obtain a better understanding of the dynamics and the consequences of the rapid, coordinated breakdown of

Jos L. V. Broers; Nancy M. H. J. Bronnenberg; Helma J. H. Kuijpers; Bert Schutte; Christopher J. Hutchison; Frans C. S. Ramaekers

2002-01-01

146

Morphology of the Internal Elastic Lamina in Arteries from Pulmonary Hypertensive Patients: a Confocal Laser Microscopy Study  

Microsoft Academic Search

The development and progression of pulmonary hypertension lesions involve continuous remodeling of the arterial wall, including the extracellular matrix components. The integrity of the internal elastic lamina may represent a barrier to cell migration and formation of intimal proliferative lesions. Some patients with congenital cardiac shunts develop precocious intimal occlusive lesions,whereas others evolve with isolated medial hypertrophy. We studied the

Vera Demarchi Aiello; Paulo S. Gutierrez; Márcio J. F. Chaves; Antonio A. B. Lopes; Maria L. Higuchi; José A. F. Ramires

2003-01-01

147

Acetylcholine receptor aggregation parallels the deposition of a basal lamina proteoglycan during development of the neuromuscular junction  

Microsoft Academic Search

To determine the time course of synaptic differentiation, we made successive observations on identified, nerve-contacted muscle cells developing in culture. The cultures had either been stained with fluorescent (~-bungarotoxin, or were maintained in the presence of a fluorescent monoclonal antibody. These probes are directed at acetylcholine receptors (AChR) and a basal lamina proteoglycan, substances that show nearly congruent surface organizations

M. JOHN ANDERSON; F. GEORGE KLIER; KAREN E. TANGUAY

1984-01-01

148

Statistics of fracture for an elastic notched composite lamina containing Weibull fibers— Part I. Features from Monte-Carlo simulation  

Microsoft Academic Search

Monte-Carlo simulation is used to study the effects of the statistics of fiber strength on the fracture process, the fracture resistance, and the overall strength distribution for an elastic composite lamina with an internal transverse notch of N contiguous, broken fibers (0 ? N ? 51). To isolate the effects of variability in fiber strength, we assign individual fiber strengths

Irene J. Beyerlein; S. Leigh Phoenix

1997-01-01

149

Stromatolitic knobs in Storr's Lake (San Salvador, Bahamas): a model system for formation and alteration of laminae.  

PubMed

The initial lamination in young, metabolically active Scytonema knobs developing in Storr's Lake (Bahamas) results from the iterative succession of two different stages of microbial growth at the top of this microbialite. Stage 1 is dominated by vertically oriented cyanobacterial filaments and is characterized by a high porosity of the fabric. Stage 2 shows a higher microbial density with the filaments oriented horizontally and with higher carbonate content. The more developed, dense microbial community associated with Stage 2 of the Scytonema knobs rapidly degrades extracellular organic matter (EOM) and coupled to this, precipitates carbonate. The initial nucleation forms high-Mg calcite nanospheroids that progressively replace the EOM. No precipitation is observed within the thick sheath of the Scytonema filaments, possibly because of strong cross-linking of calcium and EOM (forming EOM-Ca-EOM complexes), which renders Ca unavailable for carbonate nucleation (inhibition process). Eventually, organominerals precipitate and form an initial lamina through physicochemical and microbial processes, including high rates of photosynthetic activity that lead to (13) C-enriched DIC available for initial nucleation. As this lamina moves downward by the iterative production of new laminae at the top of the microbialite, increased heterotrophic activity further alters the initial mineral product at depth. Although some rare relic preservation of 'Stage 1-Stage 2' laminae in subfossil knobs exists, the very fine primary lamination is considerably altered and almost completely lost when the knobs develop into larger and more complex morphologies due to the increased accommodation space and related physicochemical and/or biological alteration. Despite considerable differences in microstructure, the emerging ecological model of community succession leading to laminae formation described here for the Scytonema knobs can be applied to the formation of coarse-grained, open marine stromatolites. Therefore, both fine- and coarse-grained extant stromatolites can be used as model systems to understand the formation of microbialites in the fossil record. PMID:24118887

Dupraz, C; Fowler, A; Tobias, C; Visscher, P T

2013-11-01

150

Imaging of the lamina cribrosa in glaucoma: perspectives of pathogenesis and clinical applications.  

PubMed

The lamina cribrosa (LC) is a sieve-like structure in the sclera where retinal ganglion cell axons exit from the eye. The LC has been known to play a critical role in the pathogenesis of glaucoma. With the advent of imaging technologies, such as enhanced depth imaging, spectral-domain optical coherence tomography (OCT) enables us to unveil the LC in vivo features. The application of adaptive optics technology and a compensatory image-processing algorithm has further improved the visualization of the beams and pores and neural pathways of the LC and the scleral insertion sites. Monitoring the changes of these structures in relation to acute and chronic elevation of intraocular pressure would be germane to decipher the relationship between the stress and strain response of the LC and optic nerve damage and improve our understanding of glaucoma pathophysiology. While the impact of investigating the integrity of LC is substantive, considerable challenges remain for imaging the LC. Nevertheless, with the rapid development of the OCT technology, it is expected that some of these limitations can be overcome and the potentials of LC imaging will be unraveled. PMID:23768229

Kim, Tae-Woo; Kagemann, Larry; Girard, Michaël J A; Strouthidis, Nicholas G; Sung, Kyung Rim; Leung, Christopher K; Schuman, Joel S; Wollstein, Gadi

2013-09-01

151

Local N-cadherin interactions mediate distinct steps in the targeting of lamina neurons  

PubMed Central

Summary The organisation of neuronal processes into series of layers is a hallmark of many brain regions. Homophilic cell adhesion molecules of the cadherin family have been implicated in layer choice. How they contribute to the targeting of neurons to distinct layers remains unclear. Here we systematically explore the role of a classical cadherin, Drosophila N-cadherin (CadN), in the targeting of five classes of related neurons to a series of consecutive layers in the fly visual system. We show that CadN is required in lamina neurons at discrete developmental steps but not used in a layer-specific fashion. Local CadN expression patterns correlate with specific growth cone movements and CadN expression on one growth cone in a specific layer is essential for targeting of processes of another neuron to this layer. We propose that dynamic regulation of CadN enables this widely expressed protein to mediate specific local interactions during neural circuit assembly.

Nern, Aljoscha; Zhu, Yan; Zipursky, S. Lawrence

2009-01-01

152

Non-Hebbian plasticity at C-fiber synapses in rat spinal cord lamina I neurons.  

PubMed

Current concepts of memory storage are largely based on Hebbian-type synaptic long-term potentiation induced by concurrent activity of pre- and postsynaptic neurons. Little is known about non-Hebbian synaptic plasticity, which, if present in nociceptive pathways, could resolve a number of unexplained findings. We performed whole-cell patch-clamp recordings in rat spinal cord slices and found that a rise in postsynaptic [Ca(2+)]i due to postsynaptic depolarization was sufficient to induce synaptic long-term potentiation (LTP) in the absence of any presynaptic conditioning stimulation. LTP induction could be prevented by postsynaptic application of the Ca(2+) chelator BAPTA (1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid), the L-type voltage-gated calcium channel (VGCC) antagonist nifedipine, and by postsynaptic application of the NMDA receptor antagonist MK801. This indicates that synaptic potentiation was induced postsynaptically by Ca(2+) entry likely via L-type voltage-gated Ca(2+) channels (VGCC) and via NMDA receptor channels. The paired pulse ratio and the coefficient of variation remained unchanged in neurons expressing LTP, suggesting that this form of synaptic potentiation was not only induced, but also expressed postsynaptically. Postsynaptic depolarization had no influence on firing patterns, action potential shape, or neuronal excitability. An increase in [Ca(2+)]i in spinal lamina I neurons induces a non-Hebbian form of synaptic plasticity in spinal nociceptive pathways without affecting neuronal active and passive membrane properties. PMID:23707311

Naka, Asami; Gruber-Schoffnegger, Doris; Sandkühler, Jürgen

2013-04-08

153

SFRSF: Invasive Exotic Species  

NSDL National Science Digital Library

This South Florida Restoration Science Forum (SFRSF) site discusses the problem of invasive exotic species in southern Florida. Topics covered include what invasive species are, where they come from, where they exist at this time, what controls them, their effect on restoration, the use of natural enemies to tame some invasive plants, and what can be done about other invasive animals and plants. There are links provided for additional information.

154

Ultrastructure of lamellar granules coating glial cell basal lamina in the olfactory bulb and olfactory subtracts of goldfish.  

PubMed

Lamellar granules, 35 to 80 nm in diameter, are observed in the pia-arachnoid tissue of regenerated olfactory bulb and olfactory subtracts of the goldfish. The granules correspond to multiple stacks of disks which cover basal lamina of both pial and ependymal cell layers and blood vessels. The granules are also in close association with collagen fibril bundles. The granules are observed only in young goldfish or after bilateral olfactory tract transection in 1 year postoperated animals. Our findings suggest that these granules are secreted by connective tissue cells in response to damage associated with bilateral olfactory tract transection. Coexisting extracellular free granules and the granules covering basal lamina are simultaneously found in regenerated olfactory bulb and olfactory tract. Many of our findings, as far as we know, have not been described previously. The composition and function of these granules are at present unknown. PMID:7983372

Popov, V I; Moisseeva, A A; Zippel, H P

1994-01-01

155

Severe hypoplasia of the omasal laminae in a Japanese Black steer with chronic bloat--a case report.  

PubMed

An 11-month-old Japanese Black steer with chronic bloat underwent clinical and histological analyses. During the observation period, it showed normal appetite and fecal volume but persistent chronic bloat symptoms. Compared to controls, the steer's feces contained undigested large straws. Necropsy revealed normal rumen, reticulum, and abomasum but a small omasum. The rumen, reticulum, and abomasum mucosa was normal, with well-developed ruminal papillae. However, severe hypoplasia of the omasal laminae was observed along with hypoplasia reticular groove and ruminoreticular fold. The contents of the reticulum, omasum, and abomasums comprised undigested large sized hay particles. The omasum papillae showed no pathological abnormalities. This is a rare case of a steer with chronic bloat probably caused by severe hypoplasia of the omasal laminae. PMID:18176026

Takagi, Mitsuhiro; Mukai, Shuhei; Fushimi, Yasuo; Matsushita, Kouhei; Miyoshi, Nobuaki; Yasuda, Nobuhiro; Kitajima, Hideo; Takamure, Senro; Matsushita, Toshihiko; Kitamura, Nobuo; Deguchi, Eisaburo

2007-12-01

156

Sprouting of A-fibre primary afferents into lamina II in two rat models of neuropathic pain  

Microsoft Academic Search

Following peripheral nerve section, injured sensory A-fibres into lamina II of the dorsal horn and form aberrant functional synapses. Such structural changes may underlie some of the sensory abnormalities observed in nerve-injured patients, including neuropathic pain. This study compared the ability of intact and injured A-fibres to sprout in two experimental models of neuropathic pain, where the onset and presence

P. Shortland; E. Kinman; C. Molander

1997-01-01

157

Both lamin A and lamin C mutations cause lamina instability as well as loss of internal nuclear lamin organization  

SciTech Connect

We have applied the fluorescence loss of intensity after photobleaching (FLIP) technique to study the molecular dynamics and organization of nuclear lamin proteins in cell lines stably transfected with green fluorescent protein (GFP)-tagged A-type lamin cDNA. Normal lamin A and C proteins show abundant decoration of the inner layer of the nuclear membrane, the nuclear lamina, and a generally diffuse localization in the nuclear interior. Bleaching studies revealed that, while the GFP-tagged lamins in the lamina were virtually immobile, the intranuclear fraction of these molecules was partially mobile. Intranuclear lamin C was significantly more mobile than intranuclear lamina A. In search of a structural cause for the variety of inherited diseases caused by A-type lamin mutations, we have studied the molecular organization of GFP-tagged lamin A and lamin C mutants R453W and R386K, found in Emery-Dreifuss muscular dystrophy (EDMD), and lamin A and lamin C mutant R482W, found in patients with Dunnigan-type familial partial lipodystrophy (FPLD). In all mutants, a prominent increase in lamin mobility was observed, indicating loss of structural stability of lamin polymers, both at the perinuclear lamina and in the intranuclear lamin organization. While the lamin rod domain mutant showed overall increased mobility, the tail domain mutants showed mainly intranuclear destabilization, possibly as a result of loss of interaction with chromatin. Decreased stability of lamin mutant polymers was confirmed by flow cytometric analyses and immunoblotting of nuclear extracts. Our findings suggest a loss of function of A-type lamin mutant proteins in the organization of intranuclear chromatin and predict the loss of gene regulatory function in laminopathies.

Broers, Jos L.V. [Department of Molecular Cell Biology, Box 17, Cardiovascular Research Institute Maastricht (CARIM), University of Maastricht, PO Box 616, NL-6200 MD Maastricht (Netherlands) and Department of Biomedical Engineering, Biomechanics and Tissue Engineering Eindhoven University of Technology (Netherlands)]. E-mail: jos.broers@molcelb.unimaas.nl; Kuijpers, H.J.H. [Department of Molecular Cell Biology, Box 17, Cardiovascular Research Institute Maastricht (CARIM), University of Maastricht, PO Box 616, NL-6200 MD Maastricht (Netherlands); Oestlund, C. [Departments of Medicine and of Anatomy and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, NY 10027 (United States); Worman, H.J. [Departments of Medicine and of Anatomy and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, NY 10027 (United States); Endert, J. [Department of Molecular Cell Biology, Box 17, Cardiovascular Research Institute Maastricht (CARIM), University of Maastricht, PO Box 616, NL-6200 MD Maastricht (Netherlands); Ramaekers, F.C.S. [Department of Molecular Cell Biology, Box 17, Cardiovascular Research Institute Maastricht (CARIM), University of Maastricht, PO Box 616, NL-6200 MD Maastricht (Netherlands)

2005-04-01

158

Three-dimensional lamina architecture alters light-harvesting efficiency in Fagus: a leaf-scale analysis  

Microsoft Academic Search

Summary Modification of foliage exposition and morphol- ogy by seasonal average integrated quantum flux density (Qint) was investigated in the canopies of the shade-tolerant late- successional deciduous tree species Fagus orientalis Lipsky and Fagus sylvatica L. Because the leaves were not entirely flat anywhere in the canopy, the leaf lamina was considered to be three-dimensional and characterized by the cross-sectional

STEFAN FLECK; ÜLO NIINEMETS; ALESSANDRO CESCATTI

159

The electrical responses of the retinal receptors and the lamina in the visual system of the fly musca  

Microsoft Academic Search

Slow electrical responses were recorded from receptors and from the lamina of the visual pathway of the fly Musca.(a)Receptors 1 to 6 in the retinal ommatidia are identified by their response dichroic sensitivity planes. The half-width of their angular sensitivity distributions is estimated 2.5° in dark adaptation, and found not to vary with ambient illumination. The retinula cells are only

John Scholes

1969-01-01

160

Both lamin A and lamin C mutations cause lamina instability as well as loss of internal nuclear lamin organization.  

PubMed

We have applied the fluorescence loss of intensity after photobleaching (FLIP) technique to study the molecular dynamics and organization of nuclear lamin proteins in cell lines stably transfected with green fluorescent protein (GFP)-tagged A-type lamin cDNA. Normal lamin A and C proteins show abundant decoration of the inner layer of the nuclear membrane, the nuclear lamina, and a generally diffuse localization in the nuclear interior. Bleaching studies revealed that, while the GFP-tagged lamins in the lamina were virtually immobile, the intranuclear fraction of these molecules was partially mobile. Intranuclear lamin C was significantly more mobile than intranuclear lamina A. In search of a structural cause for the variety of inherited diseases caused by A-type lamin mutations, we have studied the molecular organization of GFP-tagged lamin A and lamin C mutants R453W and R386K, found in Emery-Dreifuss muscular dystrophy (EDMD), and lamin A and lamin C mutant R482W, found in patients with Dunnigan-type familial partial lipodystrophy (FPLD). In all mutants, a prominent increase in lamin mobility was observed, indicating loss of structural stability of lamin polymers, both at the perinuclear lamina and in the intranuclear lamin organization. While the lamin rod domain mutant showed overall increased mobility, the tail domain mutants showed mainly intranuclear destabilization, possibly as a result of loss of interaction with chromatin. Decreased stability of lamin mutant polymers was confirmed by flow cytometric analyses and immunoblotting of nuclear extracts. Our findings suggest a loss of function of A-type lamin mutant proteins in the organization of intranuclear chromatin and predict the loss of gene regulatory function in laminopathies. PMID:15748902

Broers, Jos L V; Kuijpers, H J H; Ostlund, C; Worman, H J; Endert, J; Ramaekers, F C S

2004-12-20

161

Clinical study of bilateral decompression via vertebral lamina fenestration for lumbar interbody fusion in the treatment of lower lumbar instability  

PubMed Central

The aim of this study was to observe the clinical effects of bilateral decompression via vertebral lamina fenestration for lumbar interbody fusion in the treatment of lower lumbar instability. The 48 patients comprised 27 males and 21 females, aged 47–72 years. Three cases had first and second degree lumbar spondylolisthesis and all received bilateral vertebral lamina fenestration for posterior lumbar interbody fusion (PLIF) using a threaded fusion cage (TFC), which maintains the three-column spinal stability. Attention was given to ensure the correct pre-operative fenestration, complete decompression and the prevention of adhesions. After an average follow-up of 26.4 months, the one year post-operative X-ray radiographs suggested that the successful fusion rate was 88.1%, and this was 100% in the two-year post-operative radiographs. Moreover, the functional recovery rate was 97.9%. Bilateral vertebral lamina fenestration for lumbar interbody fusion is an ideal surgical method for the treatment of lower lumbar instability. The surgical method retains the spinal posterior column and middle column and results in full decompression and reliable fusion by a limited yet effective surgical approach.

GUO, SHUGUANG; SUN, JUNYING; TANG, GENLIN

2013-01-01

162

Fine-scale study of a thick stratospheric ozone lamina at the edge of the southern subtropical barrier  

NASA Astrophysics Data System (ADS)

A large-scale transport event resulting in a thick ozone lamina originating from midlatitudes is observed in the tropical stratosphere over Reunion island (55°E, 21°S). This isentropic transport was detected from stratospheric balloon-borne ozone measurements that showed the occurrence of the lamina and was investigated using different tools based on Ertel's potential vorticity (Epv) analyses. An original software (DYBAL) using surface coordinate and the equivalent length of Epv contours as diagnostic tools in conjunction with high-resolution outputs from an Epv advection model MIMOSA allows us to specify the origin of the lamina. The results indicate that a broad layer of stratospheric air was isentropically advected from midlatitudes across the southern edge of tropical reservoir and reached Reunion island on 12 July 2000. In addition, Eliassen-Palm's flux vectors, calculated from ECMWF analysis, show that planetary wave activity was quite large during that time period, with wave-breaking occurring around 30 km, and could have driven that exchange. In contrast with analyses of filamentation events based on model and satellite data, the present study focuses on a fine-scale vertical survey from in situ measurements. The filament reported in this paper is characterized by a large vertical extension and is located around the maximum of ozone concentration in the tropical stratosphere (600 K). The analysis of such events, poorly documented in the tropics, could complement satellite studies and contribute to a better determination of the transport between the tropics and the midlatitudes.

Portafaix, Thierry; Morel, BéAtrice; Bencherif, Hassan; Baldy, Serge; Godin-Beekmann, Sophie; Hauchecorne, Alain

2003-03-01

163

Neurotransmitters alter the numbers of synapses and organelles in photoreceptor terminals in the lamina of the housefly, Musca domestica.  

PubMed

Various organelles in the lamina terminals of housefly photoreceptors exhibit daily rhythms having a circadian basis. These include changes in the numbers of photoreceptor tetrad and L2 feedback synapses, and longitudinal movements of screening pigment. Circadian information has previously been suggested to spread from the clock to the lamina via widefield cells expressing either 5-hydroxytryptamine or pigment-dispersing hormone-like immunoreactivity. We examined the action of these neuromodulators, and other candidate neurotransmitters, 4 h after injecting either the transmitter or a control into the medulla. We counted electron microscope profiles of organelles that normally exhibit circadian changes, and two types of invagination into photoreceptor terminals, capitate projections and inter-receptor invaginations. No single substance mediated the changes observed. Injected pigment-dispersing hormone peptide decreased the number of pigment granules, implicating this peptide in screening pigment migration, but produced no changes in synapse-related organelles. alpha-Aminobutyric acid exclusively decreased the number of L2 feedback synapses. Responses to other transmitters were specific, and often large, but generally not statistically significant. Histamine, for example, may decrease the number of tetrads, possibly by direct autoregulation. The results suggest that there is likely to be more than one effector in the circadian pathways to the lamina. PMID:9861706

Pyza, E; Meinertzhagen, I A

1998-12-01

164

Retrospective Evaluation of Elastic Stain in the Assessment of Serosal Invasion of pT3N0 Colorectal Cancers.  

PubMed

Peritoneal involvement is an important adverse prognostic factor in colorectal cancer (CRC) and determines a shift in the pathologic tumor node metastasis stage. Because peritoneal involvement is difficult to identify, use of special stains highlighting the peritoneal elastic lamina and mesothelial surface has been proposed. This study aims to determine whether use of elastic stain or CK7 immunohistochemistry on a single tissue section can refine the level of tumor invasion and determine whether restaging based on this assessment has prognostic significance in pT3N0 CRCs. Elastic stains were applied to 1 block per case from 244 consecutively resected pT3N0M0 CRCs. CK7 was evaluated in a 169-case subset. The elastic lamina was identified in only 101 cases (41%). Of those, 60 cases (24.6%) displayed elastic lamina invasion (ELI). This finding was associated with significantly worse (P<0.001) disease-free survival (DFS) (5-y DFS=60%) and significantly worse (P=0.01) overall survival (OS) (5-y OS=66.7%) compared with patients with no ELI (5-y DFS=87.8%, OS=92.7%) and those for whom no elastic lamina was identified (5-y DFS=82.5%, OS=86.0%). CK7 staining highlighted mesothelial cells in only 27 of 169 cases tested and helped demonstrate serosal invasion in only 5 cases (3%). In summary, the use of a single elastic stain is a useful and inexpensive method to demonstrate peritoneal involvement by tumor and should be considered for routine use in all pT3N0 CRCs. As tumors with ELI have an adverse prognosis, we propose that they should be upstaged compared with pT3N0 tumors without ELI. PMID:23774172

Liang, Wen-Yih; Chang, Wei-Chin; Hsu, Chih-Yi; Arnason, Thomas; Berger, David; Hawkins, Alexander T; Sylla, Patricia; Lauwers, Gregory Y

2013-10-01

165

Mesoscopic Strains Maps in Woven Composite Laminas During Off-axis Tension  

NASA Astrophysics Data System (ADS)

The mechanics of woven carbon-fiber reinforced plastic (CFRP) composites is influenced by the complex architecture of the reinforcement phase. Computational (i.e. finite element based) approaches have been used increasingly to model not only the global laminate stiffness, but also damage evolution and laminate strength. The modeling combines the identification of the architectural unit cell (UC), the selection of suitable constitutive models of the different phases, the creation of a fine discretization of the UC in finite elements, the application of an incremental solution procedure that solves iteratively for the stresses and strains in the UC, [1]. The experimental validation of computational models is carried out mainly at the macroscopical level, i.e. simulation of the macroscopic stress-strain curve. Damage, however, is a localized, straindependent phenomenon and therefore only accurate strain distribution within the UC (at the mesolevel) can identify critical conditions in terms of damage location, extension and evolution. The validation of computational damage procedures is a key task and full-field optical strain analysis methods appear the ideal instrument. However, only limited examples of direct finte element method (FEM) vs experimental strain correlation are found because of the limited sensitivity and spatial resolution of some techniques and the complexity and applicative difficulty of others. The aim of the present paper is to present the application of the digital image correlation (DIC) technique, [2], to the full-field strain analysis at the mesoscopic level (i.e. within the UC) of a woven CFRP lamina when the direction of loading forms an angle to the material direction. The material under consideration is a woven carbon fiber reinforced epoxy composite. Orthogonal yarns, each made of of several thousand fibers, are woven according the twill-weave architecture is shown in Fig. 1a. Single-ply laminas were manufactured and tested to eliminate the random 3D influence of multiple-ply laminates and to favor computational model validation. Specimens with different loading directions with respect to the material principal directions were prepared and tested in a servo-hydraulic testing machine. Specimen surface preparation consisted in a speckle pattern generation to allow the application of the DIC tecnique. During the tensile experiment, the speckle pattern is recorded (frame rate of 0.1 picture/second) using a CCD camera equipped with a microscopic lens and adjustable light sources. In-house DIC software was used for in-plane displacement and strain determination and mapping. For brevity only the case of loading in the tow yarn direction is considered here. Fig. 1b shows a tipical strain map obtained with the DIC technique at an applied macroscopic strain of 0.9%. The strains are small but the DIC dechnique is sensitive enough and suitable filtering reduce the noise level of the strain maps. Strong local strain gradients are determined and referred to the yarn architecture in Fig. 1c. The DIC measurements were validated by averaging the strain over the field of view and comparing it with the macroscopic strain given by a high-sensitivity MTS extensometer. The mesoscopic srain data obtained with DIC are used to assess and validate parallel material model development by direct FEM vs experimental strain correlation. Fig. 2a shows the FEM model of the unit cell for the twill-weave architecture with a detail of the yarn geometry and finite element discretization. Suitable boundary conditions are applied to the UC model contours before the analysis, [1]. Fig. 2b shows and example of the comparison of the local longitudinal FEM/DIC strain distribution along a transverse line of Fig. 1c. The comparison shows the excellent correlation achieved both in terms of gradients and absolute strain values, [3].

Anzelotti, G.; Nicoletto, G.; Riva, E.

2010-06-01

166

Inhibitor studies of leaf lamina hydraulic conductance in trembling aspen (Populus tremuloides Michx.) leaves.  

PubMed

The present study investigated leaf water transport properties in trembling aspen (Populus tremuloides) leaves. Leaf lamina hydraulic conductance (K(lam)) and stomatal conductance (g(s)) were drastically suppressed by NaF (a general metabolic inhibitor). In leaves treated with 0.2 mM HgCl(2) (an aquaporin blocker), K(lam) declined by 22% when the leaves were sampled in June but the decline was not significant when the leaves were sampled in August. The leaves sampled in June that transpired 30 mM beta-mercaptoethanol following mercury application showed similar K(lam) as those in control leaves transpiring distilled water. When leaves were pressure-infiltrated with 0.1 mM HgCl(2), K(lam) significantly declined by 25%. Atrazine (a photosystem II inhibitor) drastically reduced leaf net CO(2) uptake by the leaves from seedlings and mature trees but did not have any effect on K(lam) regardless of the irradiance at the leaf level during the K(lam) measurements. When PTS(3) (trisodium 3-hydroxy-5,8,10-pyrenetrisulphonate) apoplastic tracer was pressure-infiltrated inside the leaves, its concentration in the leaf exudates did not change from ambient light to high irradiance treatment and declined in the presence of HgCl(2) in the treatment solution. Trembling aspen K(lam) appears to be linked to leaf metabolism and is uncoupled from the short-term variations in photosynthesis. Aquaporin-mediated water transport does not appear to constitute the dominant pathway for the pressure-driven water flow in the leaves of trembling aspen trees. PMID:20022867

Voicu, Mihaela C; Zwiazek, Janusz J

2009-12-17

167

Central control of blood pressure by nitrergic mechanisms in organum vasculosum laminae terminalis of rat brain  

PubMed Central

Experiments were carried out to explore the possible role played by the nitric oxide (NO) system in the organum vasculosum laminae terminalis (OVLT) of rat brain in arterial pressure regulation.Intracerebroventricular (ICV) or intra-OVLT administration of NO donors such as hydroxylamine, sodium nitro-prusside or s-nitro-acetylpenicillamine caused an up to 55?mmHg decrease in blood pressure (BP) but an increase in NO release (measured by porphyrin/nafion coated carbon fibre electrodes in combination with voltammetry) in the OVLT. In contrast, ICV or intra-OVLT administration of NG-nitro-L-arginine methyl ester (L-NAME; a constitutive NO synthase inhibitor) caused an up to 45?mmHg increase in BP but a fall in NO release in the OVLT.Compared with the BP responses induced by ICV injection of NO donors or NO synthase inhibitors, the OVLT route of injection required a much lower dose of NO donors or NO synthase inhibitors to produce a similar BP effect.The depressor effects induced by ICV or intra-OVLT administration of NO donors were attenuated by pretreatment with intra-OVLT injection of methylene blue (an inhibitor of guanylate cyclase), haemoglobin (a NO scavenger), L-NAME or spinal transection. On the other hand, the L-NAME-induced pressor effects were attenuated by pretreatment with intra-OVLT injection of L-arginine or spinal transection.The data suggest that activation of cyclic GMP-dependent NO synthase in the OVLT of rat brain causes cyclic GMP-dependent decreases in arterial pressure via inhibiting the sympathetic efferent activity.

Lin, M -T; Pan, S -P; Lin, J -H; Yang, Y -L

1999-01-01

168

Central control of blood pressure by nitrergic mechanisms in organum vasculosum laminae terminalis of rat brain.  

PubMed

Experiments were carried out to explore the possible role played by the nitric oxide (NO) system in the organum vasculosum laminae terminalis (OVLT) of rat brain in arterial pressure regulation. Intracerebroventricular (ICV) or intra-OVLT administration of NO donors such as hydroxylamine, sodium nitro-prusside or s-nitro-acetylpenicillamine caused an up to 55 mmHg decrease in blood pressure (BP) but an increase in NO release (measured by porphyrin/nafion coated carbon fibre electrodes in combination with voltammetry) in the OVLT. In contrast, ICV or intra-OVLT administration of N(G)-nitro-L-arginine methyl ester (L-NAME; a constitutive NO synthase inhibitor) caused an up to 45 mmHg increase in BP but a fall in NO release in the OVLT. Compared with the BP responses induced by ICV injection of NO donors or NO synthase inhibitors, the OVLT route of injection required a much lower dose of NO donors or NO synthase inhibitors to produce a similar BP effect. The depressor effects induced by ICV or intra-OVLT administration of NO donors were attenuated by pretreatment with intra-OVLT injection of methylene blue (an inhibitor of guanylate cyclase), haemoglobin (a NO scavenger), L-NAME or spinal transection. On the other hand, the L-NAME-induced pressor effects were attenuated by pretreatment with intra-OVLT injection of L-arginine or spinal transection. The data suggest that activation of cyclic GMP-dependent NO synthase in the OVLT of rat brain causes cyclic GMP-dependent decreases in arterial pressure via inhibiting the sympathetic efferent activity. PMID:10455303

Lin, M T; Pan, S P; Lin, J H; Yang, Y L

1999-07-01

169

Prelamin A and lamin A appear to be dispensable in the nuclear lamina.  

PubMed

Lamin A and lamin C, both products of Lmna, are key components of the nuclear lamina. In the mouse, a deficiency in both lamin A and lamin C leads to slow growth, muscle weakness, and death by 6 weeks of age. Fibroblasts deficient in lamins A and C contain misshapen and structurally weakened nuclei, and emerin is mislocalized away from the nuclear envelope. The physiologic rationale for the existence of the 2 different Lmna products lamin A and lamin C is unclear, although several reports have suggested that lamin A may have particularly important functions, for example in the targeting of emerin and lamin C to the nuclear envelope. Here we report the development of lamin C-only mice (Lmna(LCO/LCO)), which produce lamin C but no lamin A or prelamin A (the precursor to lamin A). Lmna(LCO/LCO) mice were entirely healthy, and Lmna(LCO/LCO) cells displayed normal emerin targeting and exhibited only very minimal alterations in nuclear shape and nuclear deformability. Thus, at least in the mouse, prelamin A and lamin A appear to be dispensable. Nevertheless, an accumulation of farnesyl-prelamin A (as occurs with a deficiency in the prelamin A processing enzyme Zmpste24) caused dramatically misshapen nuclei and progeria-like disease phenotypes. The apparent dispensability of prelamin A suggested that lamin A-related progeroid syndromes might be treated with impunity by reducing prelamin A synthesis. Remarkably, the presence of a single Lmna(LCO) allele eliminated the nuclear shape abnormalities and progeria-like disease phenotypes in Zmpste24-/- mice. Moreover, treating Zmpste24-/- cells with a prelamin A-specific antisense oligonucleotide reduced prelamin A levels and significantly reduced the frequency of misshapen nuclei. These studies suggest a new therapeutic strategy for treating progeria and other lamin A diseases. PMID:16511604

Fong, Loren G; Ng, Jennifer K; Lammerding, Jan; Vickers, Timothy A; Meta, Margarita; Coté, Nathan; Gavino, Bryant; Qiao, Xin; Chang, Sandy Y; Young, Stephanie R; Yang, Shao H; Stewart, Colin L; Lee, Richard T; Bennett, C Frank; Bergo, Martin O; Young, Stephen G

2006-03-01

170

Prelamin A and lamin A appear to be dispensable in the nuclear lamina  

PubMed Central

Lamin A and lamin C, both products of Lmna, are key components of the nuclear lamina. In the mouse, a deficiency in both lamin A and lamin C leads to slow growth, muscle weakness, and death by 6 weeks of age. Fibroblasts deficient in lamins A and C contain misshapen and structurally weakened nuclei, and emerin is mislocalized away from the nuclear envelope. The physiologic rationale for the existence of the 2 different Lmna products lamin A and lamin C is unclear, although several reports have suggested that lamin A may have particularly important functions, for example in the targeting of emerin and lamin C to the nuclear envelope. Here we report the development of lamin C–only mice (Lmna+/+), which produce lamin C but no lamin A or prelamin A (the precursor to lamin A). Lmna+/+ mice were entirely healthy, and Lmna+/+ cells displayed normal emerin targeting and exhibited only very minimal alterations in nuclear shape and nuclear deformability. Thus, at least in the mouse, prelamin A and lamin A appear to be dispensable. Nevertheless, an accumulation of farnesyl–prelamin A (as occurs with a deficiency in the prelamin A processing enzyme Zmpste24) caused dramatically misshapen nuclei and progeria-like disease phenotypes. The apparent dispensability of prelamin A suggested that lamin A–related progeroid syndromes might be treated with impunity by reducing prelamin A synthesis. Remarkably, the presence of a single LmnaLCO allele eliminated the nuclear shape abnormalities and progeria-like disease phenotypes in Zmpste24–/– mice. Moreover, treating Zmpste24–/– cells with a prelamin A–specific antisense oligonucleotide reduced prelamin A levels and significantly reduced the frequency of misshapen nuclei. These studies suggest a new therapeutic strategy for treating progeria and other lamin A diseases.

Fong, Loren G.; Ng, Jennifer K.; Lammerding, Jan; Vickers, Timothy A.; Meta, Margarita; Cote, Nathan; Gavino, Bryant; Qiao, Xin; Chang, Sandy Y.; Young, Stephanie R.; Yang, Shao H.; Stewart, Colin L.; Lee, Richard T.; Bennett, C. Frank; Bergo, Martin O.; Young, Stephen G.

2006-01-01

171

Lamina-Specific Functional MRI of Retinal and Choroidal Responses to Visual Stimuli  

PubMed Central

Purpose. To demonstrate lamina-specific functional magnetic resonance imaging (MRI) of retinal and choroidal responses to visual stimulation of graded luminance, wavelength, and frequency. Materials and Methods. High-resolution (60 × 60?m) MRI was achieved using the blood-pool contrast agent, monocrystalline iron oxide nanoparticles (MION) and a high-magnetic-field (11.7 T) scanner to image functional changes in the normal rat retina associated with various visual stimulations. MION functional MRI measured stimulus-evoked blood-volume (BV) changes. Graded luminance, wavelength, and frequency were investigated. Stimulus-evoked fMRI signal changes from the retinal and choroidal vascular layers were analyzed. Results. MRI revealed two distinct laminar signals that corresponded to the retinal and choroidal vascular layers bounding the retina and were separated by the avascular layer in between. The baseline outer layer BV index was 2–4 times greater than the inner layer BV, consistent with higher choroidal vascular density. During visual stimulation, BV responses to flickering light of different luminance, frequency, and wavelength in the inner layer were greater than those in the outer layer. The inner layer responses were dependent on luminance, frequency, and wavelength, whereas the outer layer responses were not, suggesting differential neurovascular coupling between the two vasculatures. Conclusions. This is the first report of simultaneous resolution of layer-specific functional responses of the retinal and choroid vascular layers to visual stimulation in the retina. This imaging approach could have applications in early detection and longitudinal monitoring of retinal diseases where retinal and choroidal hemodynamics may be differentially perturbed at various stages of the diseases.

Shih, Yen-Yu I.; De La Garza, Bryan H.; Muir, Eric R.; Rogers, William E.; Harrison, Joseph M.; Kiel, Jeffrey W.

2011-01-01

172

Lamina-Specific Anatomic Magnetic Resonance Imaging of the Human Retina  

PubMed Central

Purpose. Magnetic resonance imaging (MRI) of the human retina faces two major challenges: eye movement and hardware limitation that could preclude human retinal MRI with adequate spatiotemporal resolution. This study investigated eye-fixation stability and high-resolution anatomic MRI of the human retina on a 3-Tesla (T) MRI scanner. Comparison was made with optical coherence tomography (OCT) on the same subjects. Methods. Eye-fixation stability of protocols used in MRI was evaluated on four normal volunteers using an eye tracker. High-resolution MRI (100 × 200 × 2000 ?m) protocol was developed on a 3-T scanner. Subjects were instructed to maintain stable eye fixation on a target with cued blinks every 8 seconds during MRI. OCT imaging of the retina was performed. Retinal layer thicknesses measured with MRI and OCT were analyzed for matching regions of the same eyes close to the optic nerve head. Results. The temporal SDs of the horizontal and vertical displacements were 78 ± 51 and 130 ± 51 ?m (±SD, n = 4), respectively. MRI detected three layers within the human retina, consistent with MRI findings in rodent, feline, and baboon retinas. The hyperintense layer 1 closest to the vitreous likely consisted of nerve fiber, ganglion cell, and inner nuclear layer; the hypointense layer 2, the outer nuclear layer and the inner and outer segments; and the hyperintense layer 3, the choroid. The MRI retina/choroid thickness was 711 ± 37 ?m, 19% (P < 0.05) thicker than OCT thickness (579 ± 34 ?m). Conclusions. This study reports high-resolution MRI of lamina-specific structures in the human retina. These initial results are encouraging. Further improvement in spatiotemporal resolution is warranted.

Zhang, Yi; Nateras, Oscar San Emeterio; Peng, Qi; Kuranov, Roman V.; Harrison, Joseph M.; Milner, Thomas E.

2011-01-01

173

Bence-Jones protein-type myeloma with amyloid myopathy presenting as amyloidomas and extensive amyloid deposits in the muscularis propria: a rapidly fatal autopsy case.  

PubMed

This study reports a 59-year-old man who suffered from multiple skeletal muscle amyloidomas and showed a rapidly fatal course. He noticed left inguinal pain and gait disturbance due to muscle weakness of the left leg. Protein in urine (3.3 g/d) and Bence-Jones protein of the ? type (2.3 g/d) were detected. Bone marrow aspiration showed 11.6% monoclonal plasma cells in nucleated cells. A core needle-biopsied and resected left inguinal tumor showed the deposition of eosinophilic amorphous materials positive for Congo red stain and the ?-light chain. He was diagnosed with plasma cell myeloma with AL (amyloid light chain) amyloidosis. Multiple soft-part tumors developed, grew rapidly, and he died 3 months after admission. At autopsy, 3 large amyloidomas were observed in the skeletal muscles, and prominent amyloid deposits were also seen in the diaphragm, intercostal muscle, iliopsoas muscle, and cervical skeletal muscles examined. Massive amyloid materials deposited diffusely in the propria muscularis of the gastrointestinal tract: the tongue to the rectum. PMID:21632635

Ikezawa, Yoshiyasu; Oka, Kuniyuki; Nagayama, Reizo; Okubo, Yuki; Yonekawa, Nobuo; Hirai, Futoshi; Ebihara, Itaru; Mori, Naoyoshi

2011-06-01

174

Collateral projections of neurons in laminae I, III, and IV of rat spinal cord to thalamus, periaqueductal gray matter, and lateral parabrachial area.  

PubMed

Projection neurons in lamina I, together with those in laminae III-IV that express the neurokinin 1 receptor (NK1r), form a major route through which nociceptive information reaches the brain. Axons of these cells innervate various targets, including thalamus, periaqueductal gray matter (PAG), and lateral parabrachial area (LPb), and many cells project to more than one target. The aims of this study were to quantify projections from cervical enlargement to PAG and LPb, to determine the proportion of spinothalamic neurons at lumbar and cervical levels that were labelled from PAG and LPb, and to investigate morphological differences between projection populations. The C7 segment contained fewer lamina I spinoparabrachial cells than L4, but a similar number of spino-PAG cells. Virtually all spinothalamic lamina I neurons at both levels were labelled from LPb and between one-third and one-half from PAG. This suggests that significant numbers project to all three targets. Spinothalamic lamina I neurons differed from those labelled only from LPb in that they were generally larger, were more often multipolar, and (in cervical enlargement) had stronger NK1r immunoreactivity. Most lamina III/IV NK1r cells at both levels projected to LPb, but few were labelled from PAG. The great majority of these cells in C7 and over one-fourth of those in L4 were spinothalamic, and at each level some projected to both thalamus and LPb. These results confirm that neurons in these laminae have extensive collateral projections and suggest that different neuronal subpopulations in lamina I have characteristic patterns of supraspinal projection. PMID:19496168

Al-Khater, Khulood M; Todd, Andrew J

2009-08-20

175

The neuronal population of the marginal zone (lamina I) of the rat spinal cord. A study based on reconstructions of serially sectioned cells  

Microsoft Academic Search

Complete series of silver-stained semithin transverse sections were used to reconstruct 177 nerve cells of rat lamina I. According to the three-dimensional shape of the perikarya and the number and orientation of primary dendritic trunks, lamina I cells formed four distinct groups: (1) Fusiform cells with long rostrocaudal axis and having 1–4 primary dendrites oriented rostrocaudally or ventrally, which were

Deolinda Lima; Antonio Coimbra

1983-01-01

176

A novel wide-field neuron with branches in the lamina of the Drosophila visual system expresses myoinhibitory peptide and may be associated with the clock  

Microsoft Academic Search

Although neuropeptides are widespread throughout the central nervous system of the fruifly Drosophila, no records exist of peptidergic neurons in the first synaptic region of the visual system, the lamina. Here, we describe\\u000a a novel type of neuron that has wide-field tangential arborizations just distal to the lamina neuropil and that expresses\\u000a myoinhibitory peptide (MIP). The cell bodies of these

Agata Kolodziejczyk; Dick R. Nässel

2011-01-01

177

A role for heparan sulfate proteoglycans in Plasmodium falciparum sporozoite invasion of anopheline mosquito salivary glands  

PubMed Central

HS (heparan sulfate) has been shown to be an important mediator of Plasmodium sporozoite homing and invasion of the liver, but the role of this glycosaminoglycan in mosquito vector host–sporozoite interactions is unknown. We have biochemically characterized the function of AgOXT1 (Anopheles gambiae peptide-O-xylosyltransferase 1) and confirmed that AgOXT1 can modify peptides representing model HS and chondroitin sulfate proteoglycans in vitro. Moreover, we also demonstrated that the mosquito salivary gland basal lamina proteoglycans are modified by HS. We used RNA interference-mediated knockdown of HS biosynthesis in A. gambiae salivary glands to determine whether Plasmodium falciparum sporozoites that are released from mosquito midgut oocysts use salivary gland HS as a receptor for tissue invasion. Our results suggest that salivary gland basal lamina HS glycosaminoglycans only partially mediate midgut sporozoite invasion of this tissue, and that in the absence of HS, the presence of other surface co-receptors is sufficient to facilitate parasite entry.

Armistead, Jennifer S.; Wilson, Iain B.H.; van Kuppevelt, Toin H.; Dinglasan, Rhoel R.

2011-01-01

178

In vivo pathway of Autographa californica baculovirus invasion and infection.  

PubMed

The pathway of Autographa californica nuclear polyhedrosis virus (AcNPV) infection in cabbage looper, Trichoplusia ni, larval midgut cells was studied by ultrastructural and virus titration methods. Enveloped virions interacted with microvilli of columnar cells resulting in apparent fusion of the viral envelope and microvillus membrane. After entry into the cell cytoplasm, the intact nucleocapsids appeared to enter the nucleus through nuclear pores, and uncoating of the viral genome took place in the nucleoplasm. Viral progeny were first observed at 8 hr postinoculation (p. i.) and the developmental cycle of the virus was essentially completed by 24 hr p.i. Inoculum virus nucleocapsids also moved to the basal plasma membrane and budded into the hemocoel through the basal lamina within 0.5 hr p.i. We propose that this budded virus, possessing an envelope with a peplomer structure, is the primary inoculum for the systemic invasion of the insect host. PMID:18635031

Granados, R R; Lawler, K A

1981-01-30

179

Minimally invasive cardiac surgery  

Microsoft Academic Search

Cardiac surgery has been the last of the surgical specialties to embrace the principles of minimal invasiveness. The complexity\\u000a and invasiveness of the procedures have presented both a problem and an opportunity to make the procedures less invasive.\\u000a Beginning with initial attempts at coronary artery bypass surgery through limited access with and without robotics, a number\\u000a of other cardiac procedures

M. J. Mack

2006-01-01

180

Invasive Species Research  

NSDL National Science Digital Library

This United States Geological Survey (USGS) website contains information about Western Ecological Research Center (WERC) projects concerning invasive species in the Pacific Southwest. Native ecosystems in this region are being threatened by invasion of non-native plant and animal species. This project is to detect, monitor, and predict the effect and threat of invasive species on the region. Case studies of particular ecosystems include the Mojave Desert, Sonoran Desert, Sierra Nevada Mountains, and San Joaquin Valley.

181

Elevated maxi-K(+) ion channel current in glaucomatous lamina cribrosa cells.  

PubMed

The connective tissue plates of the lamina cribrosa (LC) region are continuously exposed to a mechanically dynamic environment. To study how the LC cells respond to these mechanical forces, we measured the mechano-sensitive calcium dependent maxi-K(+) ion channel current in the cell membrane of LC cells of glaucoma and normal subjects. Primary culture LC cells from 7 normal and 7 age matched glaucoma donors were studied. Perfusion of cells with hypotonic solution was used to stretch the cell membrane. Whole-cell patch-clamp technique was used to measure the basal (non stretched) and hypotonic stretch-induced changes in maxi-K(+) ion channel activity in normal and glaucoma LC cells. The role of membrane-type Ca(2+) entry channel inhibition (verapamil) and internal Ca(2+) store re-uptake blockade (2-APB) on maxi-K(+) activity was also examined. Basal and stretched-induced maxi-K(+) current were significantly elevated in the glaucoma LC cells compared to normal controls (p < 0.05). In normal LC cells hypotonic stretch elevated the mean maxi-K(+) current from 18.5 ± 5.7 pA/pF (at Vp = +100 mV) to 88.4 ± 12.4 pA/pF (P < 0.05), and from 39.5 ± 7.3 pA/pF to 133.1 ± 18.5 pA/pF in glaucoma LC cells (P < 0.02). Verapamil and 2-APB significantly reduced basal maxi-K(+) current in glaucoma LC cells (33.1 ± 8.2 pA/pF to 17.9 ± 5.6 pA/pF; and 32.2 ± 8.3 pA/pF to 17.3 ± 5.4 pA/pF, P < 0.05, respectively) but not in normal LC cells (P > 0.05). Following hypotonic stretch, verapamil and 2-APB significantly (P < 0.05) reduced the maxi-K(+) current in both normal and glaucoma LC cells. Baseline and hypotonic stretch induced Ca(2+)-dependent maxi-K(+) channel activity are elevated in LC cells of glaucoma patients, which may result from the abnormally high levels of intracellular calcium in glaucoma LC cells. PMID:23906962

Irnaten, Mustapha; Barry, Richard C; Wallace, Deborah M; Docherty, Neil G; Quill, Barry; Clark, Abbot F; O'Brien, Colm J

2013-07-29

182

Impact of laminitis on the canonical Wnt signaling pathway in basal epithelial cells of the equine digital laminae.  

PubMed

The digital laminae is a two layer tissue that attaches the distal phalanx to the inner hoof wall, thus suspending the horse's axial skeleton in the hoof capsule. This tissue fails at the epidermal:dermal junction in laminitic horses, causing crippling disease. Basal epithelial cells line the laminar epidermal:dermal junction, undergo physiological change in laminitic horses, and lose versican gene expression. Versican gene expression is purportedly under control of the canonical Wnt signaling pathway and is a trigger for mesenchymal-to-epithelial transition; thus, its repression in laminar epithelial cells of laminitic horses may be associated with suppression of the canonical Wnt signaling pathway and loss of the epithelial cell phenotype. In support of the former contention, we show, using laminae from healthy horses and horses with carbohydrate overload-induced laminitis, quantitative real-time polymerase chain reaction, Western blotting after sodium dodecylsulfate polyacrylamide gel electrophoresis, and immunofluorescent tissue staining, that positive and negative regulatory components of the canonical Wnt signaling pathway are expressed in laminar basal epithelial cells of healthy horses. Furthermore, expression of positive regulators is suppressed and negative regulators elevated in laminae of laminitic compared to healthy horses. We also show that versican gene expression in the epithelial cells correlates positively with that of ?-catenin and T-cell Factor 4, consistent with regulation by the canonical Wnt signaling pathway. In addition, gene and protein expression of ?-catenin correlates positively with that of integrin ?4 and both are strongly suppressed in laminar basal epithelial cells of laminitic horses, which remain E-cadherin(+)/vimentin(-), excluding mesenchymal transition as contributing to loss of the adherens junction and hemidesmosome components. We propose that suppression of the canonical Wnt signaling pathway, and accompanying reduced expression of ? catenin and integrin ?4 in laminar basal epithelial cells reduces cell:cell and cell:basement membrane attachment, thus, destabilizing the laminar epidermal:dermal junction. PMID:23405249

Wang, Le; Pawlak, Erica A; Johnson, Philip J; Belknap, James K; Eades, Susan; Stack, Sharon; Cousin, Helene; Black, Samuel J

2013-02-06

183

Impact of Laminitis on the Canonical Wnt Signaling Pathway in Basal Epithelial Cells of the Equine Digital Laminae  

PubMed Central

The digital laminae is a two layer tissue that attaches the distal phalanx to the inner hoof wall, thus suspending the horse's axial skeleton in the hoof capsule. This tissue fails at the epidermal:dermal junction in laminitic horses, causing crippling disease. Basal epithelial cells line the laminar epidermal:dermal junction, undergo physiological change in laminitic horses, and lose versican gene expression. Versican gene expression is purportedly under control of the canonical Wnt signaling pathway and is a trigger for mesenchymal-to-epithelial transition; thus, its repression in laminar epithelial cells of laminitic horses may be associated with suppression of the canonical Wnt signaling pathway and loss of the epithelial cell phenotype. In support of the former contention, we show, using laminae from healthy horses and horses with carbohydrate overload-induced laminitis, quantitative real-time polymerase chain reaction, Western blotting after sodium dodecylsulfate polyacrylamide gel electrophoresis, and immunofluorescent tissue staining, that positive and negative regulatory components of the canonical Wnt signaling pathway are expressed in laminar basal epithelial cells of healthy horses. Furthermore, expression of positive regulators is suppressed and negative regulators elevated in laminae of laminitic compared to healthy horses. We also show that versican gene expression in the epithelial cells correlates positively with that of ?-catenin and T-cell Factor 4, consistent with regulation by the canonical Wnt signaling pathway. In addition, gene and protein expression of ?-catenin correlates positively with that of integrin ?4 and both are strongly suppressed in laminar basal epithelial cells of laminitic horses, which remain E-cadherin+/vimentin?, excluding mesenchymal transition as contributing to loss of the adherens junction and hemidesmosome components. We propose that suppression of the canonical Wnt signaling pathway, and accompanying reduced expression of ? catenin and integrin ?4 in laminar basal epithelial cells reduces cell:cell and cell:basement membrane attachment, thus, destabilizing the laminar epidermal:dermal junction.

Wang, Le; Pawlak, Erica A.; Johnson, Philip J.; Belknap, James K.; Eades, Susan; Stack, Sharon; Cousin, Helene; Black, Samuel J.

2013-01-01

184

Reproducibility of Measuring Lamina Cribrosa Pore Geometry in Human and Nonhuman Primates with In Vivo Adaptive Optics Imaging  

PubMed Central

Purpose. The ability to consistently resolve lamina cribrosa pores in vivo has applications in the study of optic nerve head and retinal disease mechanisms. Repeatability was assessed in imaging laminar pores in normal living eyes with a confocal adaptive optics scanning laser ophthalmoscope (AOSLO). Methods. Reflectance images (840 nm) of the anterior lamina cribrosa were acquired using the AOSLO in four or more different sessions in two normal rhesus monkey eyes and three normal human eyes. Laminar pore areas, elongations (ratio of major to minor axes of the best-fit ellipse) and nearest neighbor distances were calculated for each session. Measurement repeatability was assessed across sessions. Results. Pore areas ranged from 90 to 4365 ?m2 in monkeys and 154 to 6637 ?m2 in humans. Mean variabilities in measuring pore area and elongation (i.e., mean of the standard deviation of measurements made across sessions for the same pores) were 50 ?m2 (6.1%) and 0.13 (6.7%), respectively, in monkeys and 113 ?m2 (8.3%) and 0.17 (7.7%), respectively, in humans. Mean variabilities in measuring nearest neighbor distances were 1.93 ?m (5.2%) in monkeys and 2.79 ?m (4.1%) in humans. There were no statistically significant differences in any pore parameters across sessions (ANOVA, P > 0.05). Conclusions. The anterior lamina cribrosa was consistently imaged in vivo in normal monkey and human eyes. The small intersession variability in normal pore geometry suggests that AOSLO imaging could be used to measure and track changes in laminar pores in vivo during glaucomatous progression.

Li, Chaohong; Patel, Nimesh; Sredar, Nripun; Luo, Xunda; Queener, Hope; Harwerth, Ronald S.; Porter, Jason

2011-01-01

185

Peroral gene therapy of lactose intolerance using an adeno-associated virus vector  

Microsoft Academic Search

Gene therapy is usually reserved for severe and medically refractory disorders because of the toxicity, potential long-term risks and invasiveness of most gene transfer protocols. Here we show that an orally administered adeno-associated viral vector leads to persistent expression of a ß-galactosidase transgene in both gut epithelial and lamina propria cells, and that this approach results in long-term phenotypic recovery

Ruian Xu; Deborah Young; Michael G. Kaplitt; Robert S. Sherwin; Paola Leone

1998-01-01

186

Nuclear lamina defects cause ATM-dependent NF-?B activation and link accelerated aging to a systemic inflammatory response  

PubMed Central

Alterations in the architecture and dynamics of the nuclear lamina have a causal role in normal and accelerated aging through both cell-autonomous and systemic mechanisms. However, the precise nature of the molecular cues involved in this process remains incompletely defined. Here we report that the accumulation of prelamin A isoforms at the nuclear lamina triggers an ATM- and NEMO-dependent signaling pathway that leads to NF-?B activation and secretion of high levels of proinflammatory cytokines in two different mouse models of accelerated aging (Zmpste24?/? and LmnaG609G/G609G mice). Causal involvement of NF-?B in accelerated aging was demonstrated by the fact that both genetic and pharmacological inhibition of NF-?B signaling prevents age-associated features in these animal models, significantly extending their longevity. Our findings provide in vivo proof of principle for the feasibility of pharmacological modulation of the NF-?B pathway to slow down the progression of physiological and pathological aging.

Osorio, Fernando G.; Barcena, Clea; Soria-Valles, Clara; Ramsay, Andrew J.; de Carlos, Felix; Cobo, Juan; Fueyo, Antonio; Freije, Jose M.P.; Lopez-Otin, Carlos

2012-01-01

187

The use of ligament efficiency to model fenestrations in the internal elastic lamina of cerebral arteries. I--modelling scheme.  

PubMed

The spatial geometry of fenestrations (windows) in the internal elastic lamina from human cerebral arteries is being characterized by a single parameter termed 'ligament efficiency', which is a ratio of the solid band of material to the centre-to-centre spacing between two or more holes. As a result, the apparent random distribution of fenestrations with variable diameters may be represented as a uniform array of holes with a single diameter. The actual arrangement of fenestrations from three separate tissue specimens were replicated in thin latex sheets by transposing the image of the fenestrations from photomicrographs obtained with the scanning electron microscope. In a similar manner, the uniform array of holes with an equivalent ligament efficiency are modelled in latex sheets. The tensile (stress-strain) properties of the latex sheets representing the replication and model configurations were comparable for all three specimens, even though their individual ligament efficiencies were different. The close similarity between the elastic characteristics for the two configurations, verifies the application of ligament efficiency to represent the spatial geometry of a perforated material such as the fenestrated internal elastic lamina. PMID:6643526

Campbell, G J; Roach, M R

1983-01-01

188

Rapid Development of Brain Abscess Caused by Streptococcus Pyogenes Following Penetrating Skull Injury via the Ethmoidal Sinus and Lamina Cribrosa  

PubMed Central

Objective Streptococcus pyogenes is a beta-hemolytic bacterium that belongs to Lancefield serogroup A, also known as group A streptococci (GAS). There have been five reported case in terms of PubMed-based search but no reported case of brain abscess caused by Streptococcus pyogenes as a result of penetrating skull injury. We present a patient who suffered from penetrating skull injury that resulted in a brain abscess caused by Streptococcus pyogenes. Methods The patient was a 12-year-old boy who fell down from his bicycle while cycling and ran into a tree. A wooden stick penetrated his skin below the right lower eyelid and advanced to the cranium. He lost consciousness on the fifth day of the incident and his body temperature was measured as 40?. While being admitted to our hospital, a cranial computed tomography revealed a frontal cystic mass with a perilesional hypodense zone of edema. There was no capsule formation around the lesion after intravenous contrast injection. Paranasal CT showed a bone defect located between the ethmoidal sinus and lamina cribrosa. Results Bifrontal craniotomy was performed. The abscess located at the left frontal lobe was drained and the bone defect was repaired. Conclusion Any penetrating lesion showing a connection between the lamina cribrosa and ethmoidal sinus may result in brain abscess caused by Streptococcus pyogenes. These patients should be treated urgently to repair the defect and drain the abscess with appropriate antibiotic therapy started due to the fulminant course of the brain abscess caused by this microorganism.

Aydin, Gerilmez; Comert, Serhat; Altinors, Nur

2010-01-01

189

Lamina I-periaqueductal gray (PAG) projections represent only a limited part of the total spinal and caudal medullary input to the PAG in the cat.  

PubMed

The periaqueductal gray is well known for its involvement in nociception control, but it also plays an important role in the emotional motor system. To accomplish these functions the periaqueductal gray receives input from the limbic system and from the caudal brainstem and spinal cord. Earlier studies gave the impression that the majority of the periaqueductal gray projecting cells in caudal brainstem and spinal cord are located in the contralateral lamina I, which is involved in nociception. The present study in the cat, however, demonstrates that of all periaqueductal gray projecting neurons in the contralateral caudal medulla less than 7% was located in lamina I. Of the spinal periaqueductal gray projecting neurons less than 29% was located in lamina I. However, within the spinal cord large segmental differences exist: in few segments of the enlargements the lamina I-periaqueductal gray projecting neurons represent a majority. In conclusion, although the lamina I-periaqueductal gray projection is a very important nociceptive pathway, it constitutes only a limited part of the total projection from the caudal medulla and spinal cord to the periaqueductal gray. These results suggest that a large portion of the medullo- and spino-periaqueductal gray pathways conveys information other than nociception. PMID:11275406

Mouton, L J; Klop, E; Holstege, G

2001-01-15

190

Invasion Ecology (Student Edition)  

NSDL National Science Digital Library

Strange intruders are invading our part of the world, threatening our environment and our economy. These newcomers and their impact on our ecological balance are the focus of Invasion Ecology, a guide to learning skills for investigating the behaviors on non-native and native species. Studying invaders such as zebra mussels, chestnut blight, purple loosestrife, and Phragmites, you will explore how scientists are fighting these aggressors with biological controls. This Student Edition has three sections: (1) Background on the science of ecology and its place in the control of invasive species (2) Protocols for practicing methods that scientists use in monitoring invasive species, such as early detection surveys, plot sampling, transect surveys, and decomposition studies (3) A series of helpful worksheets to guide you through your own interactive research Invasion Ecology is the second volume in the four-part Environmental Inquiry curriculum series, designed to show you how to apply scientific knowledge to solving real-life problems.

Krasny, Marianne E.; Team, The E.

2003-01-01

191

Invasive and Exotic Insects  

NSDL National Science Digital Library

Information needed to help identify and control invasive species. Specifically, each species listed has an accompanying photo, information concerning identification, biology, control and management resources. This is an outstanding resource.

0002-11-30

192

MARveling at parasite invasion  

PubMed Central

Micronemal proteins (MICs) are key mediators of cytoadherence and invasion for Toxoplasma gondii. Emerging evidence indicates that carbohydrate binding facilitates Toxoplasma entry into host cells. TgMIC1s recently solved structure reveals the presence of novel specialized domains able to discriminate between glycan residues. Comparison with Plasmodium erythrocyte-binding antigen 175 reveals that terminal sialic acid residues may represent a shared but tailored invasion pathway among apicomplexan parasites.

Hager, Kristin M.; Carruthers, Vern B.

2009-01-01

193

Minimally invasive lumbar foraminotomy.  

PubMed

Lumbar radiculopathy is a common problem. Nerve root compression can occur at different places along a nerve root's course including in the foramina. Minimal invasive approaches allow easier exposure of the lateral foramina and decompression of the nerve root in the foramina. This video demonstrates a minimally invasive approach to decompress the lumbar nerve root in the foramina with a lateral to medial decompression. The video can be found here: http://youtu.be/jqa61HSpzIA. PMID:23829856

Deutsch, Harel

2013-07-01

194

Microbial ecology of biological invasions  

Microsoft Academic Search

Invasive microbes, plants and animals are a major threat to the composition and functioning of ecosystems; however, the mechanistic basis of why exotic species can be so abundant and disruptive is not well understood. Most studies have focused on invasive plants and animals, although few have considered the effects of invasive microbes, or interactions of invasive plant and animal species

Wim H van der Putten; John N Klironomos; David A Wardle; WH van der Putten

2007-01-01

195

The economics of biological invasions  

Microsoft Academic Search

Biological invasions are an economic problem. Invasions are typically the intended or unintended consequence of economic activity. They impose real costs on society, and the risk of invasion depends on human behaviour. Effective control of invasions depends on using the right economic instruments and developing the right institutions. The problem has two special features. The first is that the risks

Charles Perrings

2001-01-01

196

Plant invasions in the landscape  

Microsoft Academic Search

Biological invasions and changes in land-use are two components of global change affecting biodiversity worldwide. There is\\u000a overriding evidence that invasions can dramatically change the landscape and that particular land-use types facilitate invasions.\\u000a Still, these issues have not formally percolated into risk analysis of biological invasions, and only recently has the influence\\u000a of the surrounding landscape on invasive species spread

Montserrat Vilà; Inés Ibáñez

2011-01-01

197

Development of diagnostic and treatment strategies for glaucoma through understanding and modification of scleral and lamina cribrosa connective tissue.  

PubMed

Considerable evidence indicates that the state of ocular connective tissues and their response in glaucomatous disease affect the degree of glaucoma damage. Both experimental and clinical data suggest that improved diagnostic and prognostic information can be derived from the assessment of the mechanical responsiveness of the sclera and lamina cribrosa to intraocular pressure (IOP). Controlled mutagenesis of the sclera has produced a mouse strain that is relatively resistant to increased IOP. Alteration of the baseline scleral state can be accomplished through either increased cross-linking of fibrillar components or their reduction. The sclera is a dynamic structure, altering its structure and behavior in response to IOP change. The biochemical pathways that control these responses are fertile areas for new glaucoma treatments. PMID:23535950

Quigley, Harry A; Cone, Frances E

2013-03-28

198

Involvement of tyrosine kinase in the pyrogenic fever exerted by NOS pathways in organum vasculosum laminae terminalis.  

PubMed

Nitric oxide synthase (NOS) is an enzyme which has a distinct cytokine-inducible isoform (iNOS). Many cytokine receptors have an intracellular tyrosine kinase domain. Here we have used two tyrosine kinase inhibitors (genistein and lavendustin A) to investigate the potential role of tyrosine kinase activation in the induction on both iNOS and fever caused by lipopolysaccharide (LPS) in rabbits. Direct administration of LPS into the organum vasculosum laminae terminalis (OVLT) increased iNOS expression. These increases paralleled the increase in deep body temperature in unanesthetized rabbits. Pretreatment with genistein or lavendustin A not only reduced the fever but also attenuated the iNOS expression in the OVLT following an intra-OVLT dose of LPS. These results suggest that tyrosine phosphorylation is part of the signal transduction mechanism that mediates the induction of both iNOS and fever elicited by LPS in the OVLT of rabbit brain. PMID:10670430

Lin, M T; Lin, J H

2000-01-01

199

Relationship between tonic inhibitory currents and phasic inhibitory activity in the spinal cord lamina II region of adult mice  

PubMed Central

Phasic and tonic inhibitions are two types of inhibitory activities involved in inhibitory processing in the CNS. In the spinal cord dorsal horn, phasic inhibition is mediated by both GABAergic and glycinergic inhibitory postsynaptic currents. In contrast to phasic inhibitory currents, using patch-clamp recording technique on spinal cord slices prepared from adult mice we revealed that tonic inhibitory currents were mediated by GABAA receptors but not by glycine receptors in dorsal horn lamina II region. We found that there was a linear relationship (r = 0.85) between the amplitude of tonic inhibitory currents and the frequency of GABAergic inhibitory postsynaptic currents. Analysis of charge transfer showed that the charges carried by tonic inhibitory currents were about 6 times of charges carried by phasic inhibitory currents. The prominent charge transfer by tonic inhibitory currents and their synaptic activity dependency suggest a significant role of tonic inhibition in sensory processing.

Ataka, Toyofumi; Gu, Jianguo G

2006-01-01

200

Heterogeneity of silica and glycan-epitope distribution in epidermal idioblast cell walls in Adiantum raddianum laminae.  

PubMed

Laminae of Adiantum raddianum Presl., a fern belonging to the family Pteridaceae, are characterised by the presence of epidermal fibre-like cells under the vascular bundles. These cells were thought to contain silica bodies, but their thickened walls leave no space for intracellular silica suggesting it may actually be deposited within their walls. Using advanced electron microscopy in conjunction with energy dispersive X-ray microanalysis we showed the presence of silica in the cell walls of the fibre-like idioblasts. However, it was specifically localised to the outer layers of the periclinal wall facing the leaf surface, with the thick secondary wall being devoid of silica. Immunocytochemical experiments were performed to ascertain the respective localisation of silica deposition and glycan polymers. Epitopes characteristic for pectic homogalacturonan and the hemicelluloses xyloglucan and mannan were detected in most epidermal walls, including the silica-rich cell wall layers. The monoclonal antibody, LM6, raised against pectic arabinan, labelled the silica-rich primary wall of the epidermal fibre-like cells and the guard cell walls, which were also shown to contain silica. We hypothesise that the silicified outer wall layers of the epidermal fibre-like cells support the lamina during cell expansion prior to secondary wall formation. This implies that silicification does not impede cell elongation. Although our results suggest that pectic arabinan may be implicated in silica deposition, further detailed analyses are needed to confirm this. The combinatorial approach presented here, which allows correlative screening and in situ localisation of silicon and cell wall polysaccharide distribution, shows great potential for future studies. PMID:23430352

Leroux, Olivier; Leroux, Frederic; Mastroberti, Alexandra Antunes; Santos-Silva, Fernanda; Van Loo, Denis; Bagniewska-Zadworna, Agnieszka; Van Hoorebeke, Luc; Bals, Sara; Popper, Zoë A; de Araujo Mariath, Jorge Ernesto

2013-02-22

201

Synchrotron radiation X-ray fluorescence microscopy reveals a spatial association of copper on elastic laminae in rat aortic media.  

PubMed

Copper, an essential trace metal in humans, plays an important role in elastic formation. However, little is known about the spatial association between copper, elastin, and elastin producing cells. The aorta is the largest artery; the aortic media is primarily composed of the elastic lamellae and vascular smooth muscle cells, which makes it a good model to address this issue. Synchrotron radiation X-ray fluorescence microscopy (SRXRF) is a new generation technique to investigate the spatial topography of trace metals in biological samples. Recently, we utilized this technique to determine the topography of copper as well as other trace elements in aortic media of Sprague Dawley rats. A standard rat diet was used to feed Sprague Dawley rats, which contains the normal dietary requirements of copper and zinc. Paraffin embedded segments (4 ?m of thickness) of thoracic aorta were analyzed using a 10 keV incident monochromatic X-ray beam focusing on a spot size of 0.3 ?m × 0.2 ?m (horizontal × vertical). The X-ray spectrum was measured using an energy-dispersive silicon drift detector for elemental topography. Our results showed that phosphorus, sulfur, and zinc are predominately distributed in the vascular smooth muscle cells, whereas copper is dramatically accumulated in elastic laminae, indicating a preferential spatial association of copper on elastic laminae in aortic media. This finding sheds new light on the role of copper in elastic formation. Our studies also demonstrate that SRXRF allows for the visualization of trace elements in tissues and cells of rodent aorta with high spatial resolution and provides an opportunity to study the role of trace elements in vasculature. PMID:21589993

Qin, Zhenyu; Toursarkissian, Boulos; Lai, Barry

2011-05-18

202

Inactivation of retinoblastoma protein does not overcome the requirement for human cytomegalovirus UL97 in lamina disruption and nuclear egress.  

PubMed

Human cytomegalovirus (HCMV) encodes one conventional protein kinase, UL97. During infection, UL97 phosphorylates the retinoblastoma tumor suppressor protein (pRb) on sites ordinarily phosphorylated by cyclin-dependent kinases (CDK), inactivating the ability of pRb to repress host genes required for cell cycle progression to S phase. UL97 is important for viral DNA synthesis in quiescent cells, but this function can be replaced by human papillomavirus type 16 E7, which targets pRb for degradation. However, viruses in which E7 replaces UL97 are still defective for virus production. UL97 is also required for efficient nuclear egress of viral nucleocapsids, which is associated with disruption of the nuclear lamina during infection, and phosphorylation of lamin A/C on serine 22, which antagonizes lamin polymerization. We investigated whether inactivation of pRb might overcome the requirement of UL97 for these roles, as pRb inactivation induces CDK1, and CDK1 phosphorylates lamin A/C on serine 22. We found that lamin A/C serine 22 phosphorylation during HCMV infection correlated with expression of UL97 and was considerably delayed in UL97-null mutants, even when E7 was expressed. E7 failed to restore gaps in the nuclear lamina seen in wild-type but not UL97-null virus infections. In electron microscopy analyses, a UL97-null virus expressing E7 was as impaired as a UL97-null mutant in cytoplasmic accumulation of viral nucleocapsids. Our results demonstrate that pRb inactivation is insufficient to restore efficient viral nuclear egress of HCMV in the absence of UL97 and instead argue further for a direct role of UL97 in this stage of the infectious cycle. PMID:23427156

Reim, Natalia I; Kamil, Jeremy P; Wang, Depeng; Lin, Alison; Sharma, Mayuri; Ericsson, Maria; Pesola, Jean M; Golan, David E; Coen, Donald M

2013-02-20

203

Blood-nerve barrier: distribution of anionic sites on the endothelial plasma membrane and basal lamina of dorsal root ganglia.  

PubMed

Previous investigations of the blood-nerve barrier have correlated the greater permeability of ganglionic endoneurial vessels, compared to those of nerve trunks, with the presence of fenestrations and open intercellular junctions. Recent studies have demonstrated reduced endothelial cell surface charge in blood vessels showing greater permeability. To determine the distribution of anionic sites on the plasma membranes and basal laminae of endothelial cells in dorsal root ganglia, cationic colloidal gold and cationic ferritin were used. Electron microscopy revealed the existence of endothelial microdomains with differing labelling densities. Labelling indicated that caveolar and fenestral diaphragms and basal laminae are highly anionic at physiological pH, luminal plasma membranes and endothelial processes are moderately charged and abluminal plasma membranes are weakly anionic. Tracers did not occur in caveolae or cytoplasmic vesicles. In vitro tracer experiments at pH values of 7.3, 5.0, 3.5 and 2.0 indicated that the anionic charge on the various endothelial domains was contributed by chemical groups with differing pKa values. In summary, the labelling of ganglionic and sciatic nerve vessels was similar except for the heavy labelling of diaphragms in a minority of endoneurial vessels in ganglia. This difference is likely to account in part for the greater permeability of ganglionic endoneurial vessels. The results are discussed with regard to the blood-nerve and -brain barriers and vascular permeability in other tissues and a comparison made between the ultrastructure and anionic microdomains of epi-, peri- and endoneurial vessels of dorsal root ganglia and sciatic nerves. PMID:1960538

Bush, M S; Reid, A R; Allt, G

1991-09-01

204

Alien invasive birds.  

PubMed

A bird species is regarded as alien invasive if it has been introduced, intentionally or accidentally, to a location where it did not previously occur naturally, becomes capable of establishing a breeding population without further intervention by humans, spreads and becomes a pest affecting the environment, the local biodiversity, the economy and/or society, including human health. European Starling (Sturnus vulgaris), Common Myna (Acridotheres tristis) and Red-vented Bulbul (Pycnonotus cafer) have been included on the list of '100 of the World's Worst Invasive Alien Species', a subset of the Global Invasive Species Database. The 'Delivering Alien Invasive Species Inventories for Europe' project has selected Canada Goose (Branta canadensis), Ruddy Duck (Oxyura jamaicensis), Rose-ringed Parakeet (Psittacula krameri) and Sacred Ibis (Threskiornis aethiopicus) as among 100 of the worst invasive species in Europe. For each of these alien bird species, the geographic range (native and introduced range), the introduction pathway, the general impacts and the management methods are presented. PMID:20919578

Brochier, B; Vangeluwe, D; van den Berg, T

2010-08-01

205

Invasion triangle: an organizational framework for species invasion  

PubMed Central

Species invasion is a complex, multifactor process. To encapsulate this complexity into an intuitively appealing, simple, and straightforward manner, we present an organizational framework in the form of an invasion triangle. The invasion triangle is an adaptation of the disease triangle used by plant pathologists to help envision and evaluate interactions among a host, a pathogen, and an environment. Our modification of this framework for invasive species incorporates the major processes that result in invasion as the three sides of the triangle: (1) attributes of the potential invader; (2) biotic characteristics of a potentially invaded site; and (3) environmental conditions of the site. The invasion triangle also includes the impact of external influences on each side of the triangle, such as climate and land use change. This paper introduces the invasion triangle, discusses how accepted invasion hypotheses are integrated in this framework, describes how the invasion triangle can be used to focus research and management, and provides examples of application. The framework provided by the invasion triangle is easy to use by both researchers and managers and also applicable at any level of data intensity, from expert opinion to highly controlled experiments. The organizational framework provided by the invasion triangle is beneficial for understanding and predicting why species are invasive in specific environments, for identifying knowledge gaps, for facilitating communication, and for directing management in regard to invasive species.

Perkins, Lora B; Leger, Elizabeth A; Nowak, Robert S

2011-01-01

206

Intracellular Parasite Invasion Strategies  

NASA Astrophysics Data System (ADS)

Intracellular parasites use various strategies to invade cells and to subvert cellular signaling pathways and, thus, to gain a foothold against host defenses. Efficient cell entry, ability to exploit intracellular niches, and persistence make these parasites treacherous pathogens. Most intracellular parasites gain entry via host-mediated processes, but apicomplexans use a system of adhesion-based motility called ``gliding'' to actively penetrate host cells. Actin polymerization-dependent motility facilitates parasite migration across cellular barriers, enables dissemination within tissues, and powers invasion of host cells. Efficient invasion has brought widespread success to this group, which includes Toxoplasma, Plasmodium, and Cryptosporidium.

Sibley, L. D.

2004-04-01

207

Identification and Partial Characterization of a Novel 105-kDalton Lower Lamina Lucida Autoantigen Associated with a Novel Immune-Mediated Subepidermal Blistering Disease  

Microsoft Academic Search

Certain skin basement membrane components, such as bullous pemphigoid antigens and epidermolysis bullosa acquisita antigen, were discovered as a result of an autoimmune reaction. In this report, we describe a unique lamina lucida determinant associated with a novel immune-mediated subepidermal bullous dermatosis. This unique bullous dermatosis resembled severe toxic epidermal necrolysis clinically. The histologic findings resemble dermatitis herpetiformis. Direct immunofluorescence

Lawrence S. Chan; Jo-David Fine; Robert A. Briggaman; David T. Woodley; Craig Hammerberg; Rhett J. Drugge; Kevin D. Cooper

1993-01-01

208

Differential wiring of local excitatory and inhibitory synaptic inputs to islet cells in rat spinal lamina II demonstrated by laser scanning photostimulation  

PubMed Central

The substantia gelatinosa (lamina II) of the spinal dorsal horn contains inhibitory and excitatory interneurons that are thought to play a critical role in the modulation of nociception. However, the organization of the intrinsic circuitry within lamina II remains poorly understood. We used glutamate uncaging by laser scanning photostimulation to map the location of neurons that give rise to local synaptic inputs to islet cells, a major class of inhibitory interneuron in lamina II. We also mapped the distribution of sites on the islet cells that exhibited direct (non-synaptic) responses to uncaging of excitatory and inhibitory transmitters. Local synaptic inputs to islet cells arose almost entirely from within lamina II, and these local inputs included both excitatory and inhibitory components. Furthermore, there was a striking segregation in the location of sites that evoked excitatory versus inhibitory synaptic inputs, such that inhibitory presynaptic neurons were distributed more proximal to the islet cell soma. This was paralleled in part by a differential distribution of transmitter receptor sites on the islet cell, in that inhibitory sites were confined to the peri-somatic region while excitatory sites were more widespread. This differential organization of excitatory and inhibitory inputs suggests a principle for the wiring of local circuitry within the substantia gelatinosa.

Kato, Go; Kawasaki, Yasuhiko; Ji, Ru-Rong; Strassman, Andrew M

2007-01-01

209

Invasion Ecology (Teacher's Guide)  

NSDL National Science Digital Library

Strange intruders are invading our part of the world, threatening our environment and our economy. These newcomers and their impact on our ecological balance are the focus of Invasion Ecology, a new book that teaches students to investigate the behaviors of nonnative and native species. Studying real-life invaders such as purple loosestrife and Phragmites, students will learn about the links between biology and ecology -- and explore how scientists are fighting these aggressors with biological controls. The Teacher's Edition explains how to guide highly sophisticated inquiry and conduct interactive research. Materials are classroom-ready and include detailed background information as well as sample assessment tasks and rubrics.The companion Student Edition has three sections: � Background on the science of ecology and its place in the control of invasive species � Protocols for practicing methods that scientists use in monitoring invasive species, such as early detection surveys, plot sampling, transect surveys, and decomposition studies � A series of helpful worksheets to guide students through their own interactive research Invasion Ecology is the second volume in the four-part Environmental Inquiry curriculum series, designed to show students how to apply scientific knowledge to solving real-life problems.

Krasny, Marianne E.; Team, The E.

2003-01-01

210

Global Invasive Species Database  

NSDL National Science Digital Library

The Global Invasive Species Database was developed by the Invasive Species Specialist Group (ISSG), an international group of 100+ scientific and policy experts with the Species Survival Commission (SSC) of the International Union for the Conservation of Nature (IUCN). The entry page of the Website offers background information on invasive species and instructions on how to use the database. A section entitled 100 of the worst (ranging from Rat to Purple Loosestrife) gives viewers an idea of the type of information that will be included in the database, both in terms of expected detail and organizational structure of the database. Types of information provided for each species include Ecology, Distribution, Habitat Matches, References, and Contacts. In addition, a Predictive feature allows viewers to predict the expansion of invasive species, and the Early Warning System matches habitats that the species has already invaded with "other similar habitats around the world." Although still under construction, this database should be a powerful tool for researchers and educators, once completed.

211

CONTROL OF INVASIVE SEAWEEDS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Invasive marine seaweeds have become serious threats to ecosystems along the coasts of many countries, including the United States. The most widespread and notorious have been infestations of Caulerpa taxifolia, which now infests over 15,000 acres of Mediterranean subtidal zones. These non-native...

212

Chronic Invasive Sinus Aspergillosis  

Microsoft Academic Search

We report a case of a 60-year-old female with a history of headache for six months and poor visual acuity for several years. Physical examination revealed necrotic nasal mucosa with crust over the right osteomeatal complex. The MRI revealed soft tissue density over the right side maxillary sinus with involvement of the orbital apex. Invasive aspergillosis was confirmed by tissue

Bor-Hwang Kang; Jin-Chin Lee; Wan-Fu Su

213

Early Primary Invasion Scientists  

ERIC Educational Resources Information Center

|"We really need to get the government involved," said one student, holding his graph up to USDA scientist Steve Seefeldt. Dr. Steve studies methods to control "invasive" plants, plants that have been introduced to an area by humans and have potential to spread rapidly and negatively affect ecosystems. The first grader and his classmates had…

Spellman, Katie V.; Villano, Christine P.

2011-01-01

214

Minimally Invasive Parathyroid Surgery  

PubMed Central

Minimally invasive parathyroidectomy offers patients a less morbid surgical approach to treat primary hyperparathyroidism. Biochemically diagnosed hyperparathyroid patients undergo a preoperative sestamibi scan to localize abnormal parathyroid tissue. If the scan is positive, a focused unilateral neck exploration is performed through a 2–3 cm incision with the aid of a gamma detector to identify the radioactive, abnormal parathyroid gland(s). In the Ochsner Clinic's initial experience with minimally invasive parathyroidectomy, 34 patients were evaluated with 20 positive scans, 4 suggestive scans, and 10 negative scans. Of the 24 patients with scans demonstrating abnormal parathyroid activity, 23 were successfully managed with the minimally invasive technique. The mean total surgical time was 72.9 minutes, and the mean weight of the excised parathyroid glands was 1445.4 mg. All 10 patients with negative scans had a traditional bilateral neck exploration lasting a mean time of 146.5 minutes; the mean weight of the excised parathyroid glands was 388.6 mg. Hypercalcemia was cured in all 24 patients in the positive group and 9 of 10 patients in the negative scan group. Ochsner's initial experience with minimally invasive parathyroidectomy demonstrates that about 70% of patients can expect to be candidates for this technique, which is associated with excellent cure rates and shorter operative times.

Fuhrman, George M.; Bolton, John S.

2000-01-01

215

INVASIVE PRICKLY NIGHTSHADES AND COGONGRASS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Many of the prickly nightshades and cogongrass [Imperata cylindrica (L.) Beauv.] are troublesome invasive weeds of agriculture, forestry, urban, and natural areas. Horsenettle (Solanum carolinense L.) and robust horsenettle (S. dimidiatum Raf.) are native invasive weeds. Buffalobur (S. rostratum D...

216

National Invasive Species Management Plan  

NSDL National Science Digital Library

In February 1999, an Executive Order by President Clinton established the National Invasive Species Council (NISC) to take a leadership role in dealing with invasive species issues. As part of that order, NISC has prepared a plan "to minimize the economic and ecological impacts and the harm to animal and human health associated with invasive species." This document, "National Management Plan: Meeting the Invasive Species Challenge," is posted on the NISC Webpage, with public commentary invited through November 18, 2000.

2000-01-01

217

The stress-strain relationships in wood and fiber-reinforced plastic laminae of reinforced glued-laminated wood beams  

NASA Astrophysics Data System (ADS)

The reinforcement of wood and wood composite structural products to improve their mechanical properties has been in practice for many years. Recently, the use of high-strength fiber-reinforced plastic (FRP) as a reinforcement in such applications has been commercialized. The reinforcement is manufactured using a standard pultrusion process or alternatively a sheet-forming process commonly referred to as "pulforming". The high-modulus fibers are predominately unidirectional, although off-axis fibers are often used to enhance off-axis properties. The fibers used are either of a single type or multiple types, which are called "hybrids". Unidirectional, single, and hybrid fiber FRP physical properties and characteristics were compared to wood. Full-scale reinforced glulams were tested. Aramid-reinforced plastics (ARP) used as tensile reinforcements were found to be superior in strength applications to other types of FRP made with fiber, such as carbon and fiberglass. Carbon/aramid-reinforced plastic (CARP) was shown to be superior in both modulus and strength design situations. Fiberglass was shown to be suitable only in hybrid situations with another fiber such as aramid or carbon and only in limited use situations where modulus was a design criteria. The testing and analysis showed that the global response of reinforced glulam beams is controlled by localized strength variations in the wood such as slope of grain, knots, finger joints, etc. in the tensile zone. The elemental tensile strains in the extreme wood tensile laminae, due to global applied loads, were found to be well below the strain at failure in clear wood samples recovered from the failure area. Two areas affecting the relationship between the wood and the FRP were investigated: compatibility of the wood and FRP materials and interface characteristics between the wood and FRP. The optimum strain value at yield point for an FRP was assessed to be slightly higher than the clear wood value in tension for a species/grade to be reinforced. The effects of localized strength variations in the tensile wood laminae adjacent to the FRP were found to be the predominate cause of failure in full-scale reinforced glulams with less than 1.5% by cross section reinforcement.

Tingley, Daniel Arthur

218

Differential global and extra-cellular matrix focused gene expression patterns between normal and glaucomatous human lamina cribrosa cells  

PubMed Central

Purpose Marked extracellular matrix (ECM) remodeling occurs in the human optic nerve head in primary open angle glaucoma (POAG). The glial fibrillary acid protein (GFAP) negative lamina cribrosa cell may play an important role in this remodeling process. We report the first study of global and ECM-focused gene transcription differentials between GFAP-negative lamina cribrosa (LC) cells from normal and POAG human donors. Methods GFAP-negative LC cell lines were generated from the optic nerve tissue of four normal (n=4) and four POAG (n=4) human donors. Using Affymetrix U133A arrays the transcriptional profile between the normal and diseased groups were compared. Bioinformatic analysis was performed using robust multichip average (RMA Express) and EASE/David. Real time TaqMan PCR and immunohistochemistry analyses were performed to validate the microarray data. Results 183 genes were upregulated by greater than 1.5 fold and 220 were down regulated by greater than 1.5 fold in the POAG LC cells versus normal controls. Upregulated genes in POAG LC cells included, transforming growth factor beta 1 (TGF?1), secreted acid protein cysteine rich (SPARC), periostin (POSTN), thrombospondin-1 (THBS1), cartilage linking protein-1 (CRTL-1), and collagen type I (COL1A1), collagen type V (COL5A1), and collagen type XI (COL11A1). Downregulated ECM genes in POAG included fibulin 1 (FBLN1), decorin (DCN), and collagen type XVIII (COL18A1). All TaqMan PCR validation assays were significant (*p<0.05) and consistent with the array data. Immunohistochemistry of one target (periostin) confirmed its differential expression at the protein level in POAG optic nerve head tissue compared with non-glaucomatous controls. Functional annotation and over-representation analysis identified ECM genes as a statistically over-represented class of genes in POAG LC cells compared with normal LC cells. Conclusions This study reports for the first time that POAG LC cells in-vitro demonstrate upregulated ECM and pro-fibrotic gene expression compared with normal LC cells. This may be a pathological characteristic of this cell type in POAG in-vivo. We believe that the LC cell may be a pivotal regulator of optic nerve head ECM remodeling in POAG and an attractive target for molecular therapeutic strategies in the future.

Wordinger, Robert J.; Clark, Abbot F.; O'Brien, Colm J.

2009-01-01

219

Invasive Rodent Eradication on Islands  

Microsoft Academic Search

Invasive mammals are the greatest threat to island biodiversity and invasive rodents are likely responsible for the greatest number of extinctions and ecosystem changes. Techniques for eradicating rodents from islands were developed over 2 decades ago. Since that time there has been a significant development and application of this conservation tool. We reviewed the literature on invasive rodent eradications to

GREGG HOWALD; C. JOSH DONLAN; JUAN PABLO GALVÁN; JAMES C. RUSSELL; JOHN PARKES; ARACELI SAMANIEGO; YIWEI WANG; DICK VEITCH; PIERO GENOVESI; MICHEL PASCAL; ALAN SAUNDERS; BERNIE TERSHY

2007-01-01

220

Evolutionary genetics of invasive species  

Microsoft Academic Search

The evolutionary genetics of invasive species has been relatively unexplored, but could offer insights into mechanisms of invasions. Recent studies suggest that the invasion success of many species might depend more heavily on their ability to respond to natural selection than on broad physiological tolerance or plasticity. Thus, these studies stress the importance of genetic architecture, selection upon which could

Carol Eunmi Lee

2002-01-01

221

Risk Assessment for Invasive Species  

Microsoft Academic Search

Although estimates vary, there is a broad agreement that invasive species impose major costs on the U.S. economy, as well as posing risks to nonmarket environmental goods and services and to public health. The domestic effort to manage risks associated with invasive species is coordinated by the National Invasive Species Council (NISC), which is charged with devel- oping a science-based

Mark C. Andersen; Heather Adams; Bruce Hope; Mark Powell

2004-01-01

222

Invasive species and climate change  

USGS Publications Warehouse

Invasive species challenge managers in their work of conserving and managing natural areas and are one of the most serious problems these managers face. Because invasive species are likely to spread in response to changes in climate, managers may need to change their approaches to invasive species management accordingly.

Middleton, Beth A.

2006-01-01

223

A candidate of organum vasculosum of the lamina terminalis with neuronal connections to neurosecretory preoptic nucleus in eels.  

PubMed

Systemic angiotensin II (Ang II) is a dipsogen in terrestrial vertebrates and seawater teleosts. In eels, Ang II acts on the area postrema, a sensory circumventricular organ (CVO) and elicits water intake but other sensory CVOs have not yet been found in the eel forebrain. To identify sensory CVOs in the forebrain, eels were peripherally injected with Evans blue, which immediately binds to albumin, or a rabbit IgG protein. Extravasation of these proteins, which cannot cross the blood–brain barrier (BBB), was observed in the brain parenchyma of the anteroventral preoptic recess (PR) walls. Fenestrated capillaries were observed in the parenchymal margin of the ventral wall of the PR, confirming a deficit of the BBB in the eel forebrain. Immunostaining for tyrosine hydroxylase (TH) and choline acetyltransferase (ChAT) detected neurons in the lateral region of the anterior parvocellular preoptic nucleus (PPa), which were strongly stained by BBB-impermeable N-hydroxysulfosuccinimide. In the periventricular region of the PPa, many neurons incorporated biotinylated dextran amine conjugated to fluorescein, a retrograde axonal tracer, injected into the magnocellular preoptic nucleus (PM), indicating neuronal connections from the PPa to the PM. The mammalian paraventricular and supraoptic nuclei, homologous to the teleost PM, receive principal neuronal projections from the organum vasculosum of the lamina terminalis (OVLT). These results strongly suggest that the periventricular subpopulation of the PPa, which is most likely to be a component of the OVLT, serves as a functional window of access for systemic signal molecules such as Ang II. PMID:23797335

Mukuda, Takao; Hamasaki, Sawako; Koyama, Yuka; Takei, Yoshio; Kaidoh, Toshiyuki; Inoué, Takao

2013-09-01

224

The role of the surface fine-grained laminae in low-gradient streams: A model approach  

NASA Astrophysics Data System (ADS)

This contribution presents a model approach to simulate the erosion, entrainment, deposition, and burial of the surface fine-grained laminae (SFGL) in low-gradient streams. We hypothesized that SFGL transport acts as a geomorphic control of the erosion and transport of sediment sources in a bedrock-controlled, low-gradient stream with fluvial deposits located in central Kentucky, USA. Results indicate that the SFGL development and temporary storage on the streambed surface plays a key role in maintaining an equilibrium streambed. The SFGL provides an easily erodible sediment source that satisfies the transport capacity of the stream during low to moderate flow events and thus protects deeper streambed sediment and streambank sediments from erosion. Modeling results showed that the simulation period was characterized by low to moderate hydrologic events which flush the SFGL from the stream and high flow events which deposit fine sediments into the SFGL. During the former, transported sediments were dominated by sediments of SFGL origin, i.e., 89% of sediments. During the latter, 33% of sediment input to the stream is deposited to the SFGL, which shows its importance as a temporary sink. Our model results support a novel concept that the ephemeral SFGL layers can satisfy sediment transport capacity of flow at low to moderate flows and thus protect other sources from erosion. While perhaps the bedrock, low-gradient stream studied provides an end-member to SFGL control, future research might investigate the importance of SFGL control in other stream systems.

Russo, Joseph; Fox, James

2012-10-01

225

A bioinformatics analysis of Lamin-A regulatory network: a perspective on epigenetic involvement in Hutchinson-Gilford progeria syndrome.  

PubMed

Hutchinson-Gilford progeria syndrome (HGPS) is a rare human genetic disease that leads to premature aging. HGPS is caused by mutation in the Lamin-A (LMNA) gene that leads, in affected young individuals, to the accumulation of the progerin protein, usually present only in aging differentiated cells. Bioinformatics analyses of the network of interactions of the LMNA gene and transcripts are presented. The LMNA gene network has been analyzed using the BioGRID database (http://thebiogrid.org/) and related analysis tools such as Osprey (http://biodata.mshri.on.ca/osprey/servlet/Index) and GeneMANIA ( http://genemania.org/). The network of interaction of LMNA transcripts has been further analyzed following the competing endogenous (ceRNA) hypotheses (RNA cross-talk via microRNAs [miRNAs]) and using the miRWalk database and tools (www.ma.uni-heidelberg.de/apps/zmf/mirwalk/). These analyses suggest particular relevance of epigenetic modifiers (via acetylase complexes and specifically HTATIP histone acetylase) and adenosine triphosphate (ATP)-dependent chromatin remodelers (via pBAF, BAF, and SWI/SNF complexes). PMID:22533413

Arancio, Walter

2012-04-01

226

DLin-7 is required in postsynaptic lamina neurons to prevent light-induced photoreceptor degeneration in Drosophila.  

PubMed

Inherited retinal degeneration in humans is caused by mutations in a wide spectrum of genes that regulate photoreceptor development and homeostasis. Many of these genes are structurally and functionally conserved in Drosophila, making the fly eye an ideal system in which to study the cellular and molecular basis of blindness. DLin-7, the ortholog of vertebrate MALS/Veli, is a core component of the evolutionarily conserved Crumbs complex. Mutations in any core member of the Crb complex lead to retinal degeneration in Drosophila. Strikingly, mutations in the human ortholog, CRB1, result in retinitis pigmentosa 12 (RP12) and Leber congenital amaurosis, two severe retinal dystrophies. Unlike Crumbs, DLin-7 is expressed not only in photoreceptor cells but also in postsynaptic lamina neurons. Here, we show that DLin-7 is required in postsynaptic neurons, but not in photoreceptors such as Crumbs, to prevent light-dependent retinal degeneration. At the photoreceptor synapse, DLin-7 acts as part of a conserved DLin-7/CASK/DlgS97 complex required to control the number of capitate projections and active zones, important specializations in the photoreceptor synapse that are essential for proper neurotransmission. These results are the first to demonstrate that a postsynaptically acting protein prevents light-dependent photoreceptor degeneration and describe a novel, Crumbs-independent mechanism for photoreceptor degeneration. PMID:23850283

Soukup, Sandra-Fausia; Pocha, Shirin Meher; Yuan, Michaela; Knust, Elisabeth

2013-07-11

227

Non-invasive ventilation  

Microsoft Academic Search

Non-invasive ventilation (NIV) refers to the delivery of mechanical ventilation to the lungs using techniques that do not\\u000a require an endotracheal airway. Essentially, there are two modalities: continuous positive airway pressure (CPAP) and pressure\\u000a support ventilation (NIPSV). In acute pulmonary edema (APE) both modalities have shown a faster improvement in gas exchange\\u000a and physiologic parameters with respect to conventional oxygen

Josep Masip

2007-01-01

228

Minimally invasive (laparoscopic) surgery  

Microsoft Academic Search

  Minimally invasive (laparoscopic) surgery became a major part of general surgery with the introduction of laparoscopic cholecystectomy\\u000a in the late 1980s. This was the culmination of the development of instruments and techniques by many physicians; Kelling developing\\u000a pneumoperitoneum, Zollikofer using carbon dioxide, Kalk designing a lens system and the dual-trochar technique, Veress using\\u000a the Veress needle to create pneumoperitoneum, Hasson

H. S. Himal

2002-01-01

229

USGS invasive species solutions  

USGS Publications Warehouse

Land managers must meet the invasive species challenge every day, starting with identification of problem species, then the collection of best practices for their control, and finally the implementation of a plan to remove the problem. At each step of the process, the availability of reliable information is essential to success. The U.S. Geological Survey (USGS) has developed a suite of resources for early detection and rapid response, along with data management and sharing.

Simpson, Annie

2011-01-01

230

Minimally invasive periodontal therapy.  

PubMed

Minimally invasive dentistry is a concept that preserves dentition and supporting structures. However, minimally invasive procedures in periodontal treatment are supposed to be limited within periodontal surgery, the aim of which is to represent alternative approaches developed to allow less extensive manipulation of surrounding tissues than conventional procedures, while accomplishing the same objectives. In this review, the concept of minimally invasive periodontal surgery (MIPS) is firstly explained. An electronic search for all studies regarding efficacy and effectiveness of MIPS between 2001 and 2009 was conducted. For this purpose, suitable key words from Medical Subject Headings on PubMed were used to extract the required studies. All studies are demonstrated and important results are concluded. Preliminary data from case cohorts and from many studies reveal that the microsurgical access flap, in terms of MIPS, has a high potential to seal the healing wound from the contaminated oral environment by achieving and maintaining primary closure. Soft tissues are mostly preserved and minimal gingival recession is observed, an important feature to meet the demands of the patient and the clinician in the esthetic zone. However, although the potential efficacy of MIPS in the treatment of deep intrabony defects has been proved, larger studies are required to confirm and extend the reported positive preliminary outcomes. PMID:22368356

Dannan, Aous

2011-10-01

231

Roles for herpes simplex virus type 1 UL34 and US3 proteins in disrupting the nuclear lamina during herpes simplex virus type 1 egress  

PubMed Central

Cells infected with wild type HSV-1 showed significant lamin A/C and lamin B rearrangement, while UL34-null virus-infected cells exhibited few changes in lamin localization, indicating that UL34 is necessary for lamin disruption. During HSV infection, US3 limited the development of disruptions in the lamina, since cells infected with a US3-null virus developed large perforations in the lamin layer. US3 regulation of lamin disruption does not correlate with the induction of apoptosis. Expression of either UL34 or US3 proteins alone disrupted lamin A/C and lamin B localization. Expression of UL34 and US3 together had little effect on lamin A/C localization, suggesting a regulatory interaction between the two proteins. The data presented in this paper argue for crucial roles for both UL34 and US3 in regulating the state of the nuclear lamina during viral infection.

Bjerke, Susan L.; Roller, Richard J.

2010-01-01

232

Roles for herpes simplex virus type 1 UL34 and US3 proteins in disrupting the nuclear lamina during herpes simplex virus type 1 egress.  

PubMed

Cells infected with wild type HSV-1 showed significant lamin A/C and lamin B rearrangement, while UL34-null virus-infected cells exhibited few changes in lamin localization, indicating that UL34 is necessary for lamin disruption. During HSV infection, US3 limited the development of disruptions in the lamina, since cells infected with a US3-null virus developed large perforations in the lamin layer. US3 regulation of lamin disruption does not correlate with the induction of apoptosis. Expression of either UL34 or US3 proteins alone disrupted lamin A/C and lamin B localization. Expression of UL34 and US3 together had little effect on lamin A/C localization, suggesting a regulatory interaction between the two proteins. The data presented in this paper argue for crucial roles for both UL34 and US3 in regulating the state of the nuclear lamina during viral infection. PMID:16427676

Bjerke, Susan L; Roller, Richard J

2006-01-19

233

Lamin A and lamin C form homodimers and coexist in higher complex forms both in the nucleoplasmic fraction and in the lamina of cultured human cells.  

PubMed

We have investigated and quantified the nuclear A-type lamin pool from human HeLa S3 suspension cells with respect to their distribution to detergent soluble and insoluble fractions. We devised a sequential extraction protocol and found that maximally 10% of A-type lamins are recovered in the soluble fraction. Notably, lamin C is enriched in low detergent fractions and only with 0.5% Nonidet P-40 lamin A and C are recovered in ratios nearly equivalent to those found in whole cell extracts and in the lamina fraction. Authentic nucleoplasmic proteins such as LAP2a, pRB and p53 are co-extracted to a large part together with the A-type lamins in these fractions. By sucrose density centrifugation we revealed that the majority of lamins co-sedimented with human IgG indicating they form rather small complexes in the range of dimers and slightly larger complexes. Some lamin A - but not lamin C - is obtained in addition in a much faster sedimenting fraction. Authentic nuclear proteins such as PCNA, p53 and LAP2a were found both in the light and the heavy sucrose fractions together with lamin A. Last but not least, immunoprecipitation experiments from both soluble fractions and from RIPA lysates of whole cells revealed that lamin A and lamin C do not form heterodimers but segregate practically completely. Correspondingly, immunofluorescence microscopy of formaldehyde-fixed cells clearly demonstrated that lamin A and C are localized at least in part to distinct patches within the lamina. Hence, the structural segregation of lamin A and C is indeed retained in the nuclear envelope to some extent too. PMID:22033280

Kolb, Thorsten; Maass, Kendra; Hergt, Michaela; Aebi, Ueli; Herrmann, Harald

234

Differentiating Anti-Lamina Lucida and Anti-Sublamina Densa Anti-BMZ Antibodies by Indirect Immunofluorescence on 1.0 M Sodium Chloride-Separated Skin  

Microsoft Academic Search

Sixty-one bullous disease sera containing IgG anti-BMZ antibodies were examined by indirect immunofluorescence on intact skin and skin separated through the lamina lucida by incubation in 1.0 M NaCl. All sera produced an indistinguishable pattern of linear immunofluorescence on intact skin at dilutions of 1:10 or higher. On separated skin, antibodies bound to either the epidermal (epidermal pattern), dermal (dermal

W. Ray Gammon; Robert A. Briggaman; Alfred O. Inman III; Laurinda L. Queen; Clayton E. Wheeler

1984-01-01

235

Visual field defect caused by nerve fiber layer damage associated with an internal limiting lamina defect after uneventful epiretinal membrane surgery  

Microsoft Academic Search

PURPOSE: To report a case of visual field defect caused by damage of the nerve fiber layer associated with an internal limiting lamina defect after uneventful epiretinal membrane peeling.DESIGN: Interventional case report.METHODS: In the right eye, a 43-year-old male patient developed a nasal step and mild inferior arcuate scotoma after uneventful epiretinal membrane surgery without any associated glaucoma. Transmission electron

Chan Y. Kim; Joon H. Lee; Sung J. Lee; Hyoung J. Koh; Sung C. Lee; Oh W. Kwon

2002-01-01

236

Reduction of anion reversal potential subverts the inhibitory control of firing rate in spinal lamina I neurons: towards a biophysical basis for neuropathic pain  

Microsoft Academic Search

BACKGROUND: Reduction of the transmembrane chloride gradient in spinal lamina I neurons contributes to the cellular hyperexcitability producing allodynia and hyperalgesia after peripheral nerve injury. The resultant decrease in anion reversal potential (i.e. shift in Eanion to less negative potentials) reduces glycine\\/GABAA receptor-mediated hyperpolarization, but the large increase in membrane conductance caused by inhibitory input can nonetheless shunt concurrent excitatory

Steven A Prescott; Terrence J Sejnowski; Yves De Koninck

2006-01-01

237

Expression of basal lamina components by Schwann cells cultured on poly(lactic acid) (PLLA) and poly(caprolactone) (PCL) membranes  

Microsoft Academic Search

The present in vitro study investigated the expression of basal lamina components by Schwann cells (SCs) cultivated on PCL\\u000a and PLLA membranes prepared by solvent evaporation. Cultures of SCs were obtained from sciatic nerves from neonatal Sprague\\u000a Dawley rats and seeded on 24 well culture plates containing the polymer membranes. The purity of the cultures was evaluated\\u000a with a Schwann cell

A. Pierucci; E. A. R. Duek; A. L. R. de Oliveira

2009-01-01

238

Overexpression of Semicarbazide-Sensitive Amine Oxidase in Smooth Muscle Cells Leads to an Abnormal Structure of the Aortic Elastic Laminas  

PubMed Central

Elevated semicarbazide-sensitive amine oxidase (SSAO) activity has been observed in several human conditions, eg, diabetes, and it has been speculated that SSAO contributes to the development of vasculopathies associated with this disease. To investigate in vivo consequences of elevated expression of SSAO in vascular tissues, we have developed a transgenic model for overexpression of human SSAO in mice. A smooth muscle-specific promoter, smooth muscle ?-actin promoter 8 (SMP8) was used. Transgenic expression of human SSAO in tissues with a high content of smooth muscle cells was confirmed by Northern blot analysis. Enzymatic analysis of homogenates from transgenic tissues showed elevated levels of SSAO activity compared to non-transgenic littermates. Furthermore, when plasma SSAO activity was analyzed, much higher activity was detected compared to plasma from control mice, indicating that plasma SSAO may originate from smooth muscle cells. Histopathological evaluation of aorta and renal artery from transgenic mice revealed an abnormal structure of the elastin tissue. Instead of the regularly folded elastic laminae normally found in tunica media of sacrificed mice, the elastic laminae were straight and unfolded with irregularly arranged elastic fibers, forming tangled webs, between the intercalating elastic laminae. These alterations of the elastin structures suggest that overexpression of SSAO has led to a reduced elasticity of the arteries. Moreover, the mean femoral arterial pressure of the SMP8 SSAO transgenic mice was significantly lower in comparison to non-transgenic littermates. This suggests that the transgenic mice have a defect in their ability to regulate blood pressure.

Gokturk, Camilla; Nilsson, Joakim; Nordquist, Jenny; Kristensson, Millvej; Svensson, Kristian; Soderberg, Charlotte; Israelson, Marianne; Garpenstrand, Hakan; Sjoquist, Mats; Oreland, Lars; Forsberg-Nilsson, Karin

2003-01-01

239

Bait-lamina assay as a tool to assess the effects of metal contamination in the feeding activity of soil invertebrates within a uranium mine area.  

PubMed

As part of the tier 2 of a site-specific risk assessment, this study was the first reporting an intensive in situ application of the bait-lamina assay; two exposure periods (7 and 14 days) were tested during four seasons in ten different sites, within a uranium mine area and at two different depths. The most contaminated sites (by deposition of sludge from the effluent treatment pond) were discriminated after 14 days of exposure because extremely low percentages of feeding activity were recorded. Previous sub-lethal ecotoxicological assays, already had demonstrated that the habitat function of these soils is compromised. Nevertheless, seasonality has proved to have a significant influence on responses. Thus to strength conclusions about the impact of contaminants, the in situ bait-lamina assay should be performed on different annual seasons, at least for temperate regions. It was also found that some environmental parameters (e.g. soil moisture and litter) can act as confounding factors in the bait-lamina assay. PMID:19361901

André, A; Antunes, S C; Gonçalves, F; Pereira, R

2009-04-10

240

Interactions between plexin-A2, plexin-A4, and semaphorin 6A control lamina-restricted projection of hippocampal mossy fibers.  

PubMed

Hippocampal mossy fibers project preferentially to the stratum lucidum, the proximal-most lamina of the suprapyramidal region of CA3. The molecular mechanisms that govern this lamina-restricted projection are still unknown. We examined the projection pattern of mossy fibers in mutant mice for semaphorin receptors plexin-A2 and plexin-A4, and their ligand, the transmembrane semaphorin Sema6A. We found that plexin-A2 deficiency causes a shift of mossy fibers from the suprapyramidal region to the infra- and intrapyramidal regions, while plexin-A4 deficiency induces inappropriate spreading of mossy fibers within CA3. We also report that the plexin-A2 loss-of-function phenotype is genetically suppressed by Sema6A loss of function. Based on these results, we propose a model for the lamina-restricted projection of mossy fibers: the expression of plexin-A4 on mossy fibers prevents them from entering the Sema6A-expressing suprapyramidal region of CA3 and restricts them to the proximal-most part, where Sema6A repulsive activity is attenuated by plexin-A2. PMID:17296555

Suto, Fumikazu; Tsuboi, Miu; Kamiya, Haruyuki; Mizuno, Hidenobu; Kiyama, Yuji; Komai, Shoji; Shimizu, Masayuki; Sanbo, Makoto; Yagi, Takeshi; Hiromi, Yasushi; Chédotal, Alain; Mitchell, Kevin J; Manabe, Toshiya; Fujisawa, Hajime

2007-02-15

241

Structure and immunocytochemical localization of photosynthetic enzymes in the lamina joint and sheath pulvinus of the C4 grass Arundinella hirta.  

PubMed

The C(4) grass Arundinella hirta exhibits a unique C(4) anatomy, with isolated Kranz cells (distinctive cells) and C(4)-type expression of photosynthetic enzymes in the leaf sheath and stem as well as in the leaf blade. The border zones between these organs are pale green. Those between the leaf blade and sheath and between the sheath and stem are called the lamina joint and sheath pulvinus, respectively, and are involved in gravity sensing. We investigated the structure and localization of C(3) and C(4) photosynthetic enzymes in these tissues. In both zones the epidermis lacked stomata. The inner tissue was composed of parenchyma cells and vascular bundles. The parenchyma cells were densely packed with small intercellular spaces and contained granal chloroplasts with large starch grains. No C(4)-type cellular differentiation was recognized. Western blot analysis showed that the lamina joint and pulvinus accumulated substantial amounts of phosphoenolpyruvate carboxylase (PEPC), pyruvate,Pi dikinase (PPDK), and ribulose 1,5-bisphosphate carboxylase/oxygenase (rubisco). Immunogold electron microscopy revealed PEPC in the cytosol and both PPDK and rubisco in the chloroplasts of parenchyma cells, suggesting the occurrence of C(3) and C(4) enzymes within a single type of chlorenchyma cell. These data indicate that the lamina joint and pulvinus have unique expression patterns of C(3) and C(4) enzymes, unlike those in C(4)-type anatomy. PMID:23073748

Wakayama, Masataka; Ohnishi, Jun-ichi; Ueno, Osamu

2012-10-17

242

Minimally Invasive Parathyroidectomy  

PubMed Central

Minimally invasive parathyroidectomy (MIP) is an operative approach for the treatment of primary hyperparathyroidism (pHPT). Currently, routine use of improved preoperative localization studies, cervical block anesthesia in the conscious patient, and intraoperative parathyroid hormone analyses aid in guiding surgical therapy. MIP requires less surgical dissection causing decreased trauma to tissues, can be performed safely in the ambulatory setting, and is at least as effective as standard cervical exploration. This paper reviews advances in preoperative localization, anesthetic techniques, and intraoperative management of patients undergoing MIP for the treatment of pHPT.

Starker, Lee F.; Fonseca, Annabelle L.; Carling, Tobias; Udelsman, Robert

2011-01-01

243

Bioterrorism and invasive species.  

PubMed

The risk of dispersing invasive species, especially human pathogens, through acts of bioterrorism, cannot be neglected. However, that risk appears quite low in comparison with the risk of dispersing animal pathogens that could dramatically burden the agricultural economy of food animal producing countries, such as Australia and countries in Europe and North and South America. Although it is not directly related to bioterrorism, the intentional release of non-native species, particularly undesired companion animals or wildlife, may also have a major economic impact on the environment and, possibly, on animal and human health, in the case of accidental release of zoonotic agents. PMID:20919576

Chomel, B B; Sun, B

2010-08-01

244

A nitric oxide-dopamine link pathway in organum vasculosum laminae terminalis of rat brain exerts control over blood pressure  

PubMed Central

Experiments were carried out to explore the possible role played by the nitric oxide (NO) and dopamine (DA) system in the organum vasculosum laminae terminalis (OVLT) of rat brain in arterial pressure regulation. Intracerebroventricular (ICV) administration of NO donors such as hydroxylamine or sodium nitro-prusside (SNP) caused an up to 59?mmHg decrease in blood pressure (BP) and a decrease in DA release (measured by nafion coated carbon fibre electrodes in combination with voltammetry) in the OVLT. In contrast, ICV administration of NG-nitro-L-arginine methyl ester (L-NAME; a constitutive NO synthase inhibitor) or 7-nitroindazol (a neuronal NO synthase inhibitor) caused an up to 98?mmHg increase in BP and an increase in DA release in the OVLT. Intra-OVLT injection of amphetamine (0.1?–?0.3?mg), SKF 38393 (a DA D1 receptor agonist; 0.01?–?0.03?mg), or apomorphine (a DA D2,3 receptor agonist; 0.01?–?0.03?mg) caused an increase in BP. On the other hand, intra-OVLT injection of SCH23390 (a DA D1 receptor antagonist; 0.005?–?0.020?mg) or haloperidol (0.005?–?0.020?mg) caused a decrease in BP. The pressor effects induced by intra-OVLT administration of L-NAME were attenuated by pretreatment with intra-OVLT injection of haloperidol, SCF23390, or 6-hydroxydopamine. In the contrast, the hydroxylamine-, 8-Br-cGMP- or SNP-induced depressor effects were attenuated by pretreatment with intra-OVLT injection of amphetamine, SKF 38393 or apomorphine. The data suggest that activation of a NO-DA link pathway within the OVLT of rat brain exerts control over blood pressure.

Chang, C-P; Pan, S-P; Lin, M-T

2001-01-01

245

Robust adaptive 3-D segmentation of vessel laminae from fluorescence confocal microscope images and parallel GPU implementation.  

PubMed

This paper presents robust 3-D algorithms to segment vasculature that is imaged by labeling laminae, rather than the lumenal volume. The signal is weak, sparse, noisy, nonuniform, low-contrast, and exhibits gaps and spectral artifacts, so adaptive thresholding and Hessian filtering based methods are not effective. The structure deviates from a tubular geometry, so tracing algorithms are not effective. We propose a four step approach. The first step detects candidate voxels using a robust hypothesis test based on a model that assumes Poisson noise and locally planar geometry. The second step performs an adaptive region growth to extract weakly labeled and fine vessels while rejecting spectral artifacts. To enable interactive visualization and estimation of features such as statistical confidence, local curvature, local thickness, and local normal, we perform the third step. In the third step, we construct an accurate mesh representation using marching tetrahedra, volume-preserving smoothing, and adaptive decimation algorithms. To enable topological analysis and efficient validation, we describe a method to estimate vessel centerlines using a ray casting and vote accumulation algorithm which forms the final step of our algorithm. Our algorithm lends itself to parallel processing, and yielded an 8 x speedup on a graphics processor (GPU). On synthetic data, our meshes had average error per face (EPF) values of (0.1-1.6) voxels per mesh face for peak signal-to-noise ratios from (110-28 dB). Separately, the error from decimating the mesh to less than 1% of its original size, the EPF was less than 1 voxel/face. When validated on real datasets, the average recall and precision values were found to be 94.66% and 94.84%, respectively. PMID:20199906

Narayanaswamy, Arunachalam; Dwarakapuram, Saritha; Bjornsson, Christopher S; Cutler, Barbara M; Shain, William; Roysam, Badrinath

2010-03-01

246

Temporal Management of Invasive Species  

Microsoft Academic Search

Successful management of invasive species requires using spatial models of current distributions and forecasts of spread with\\u000a explicit consideration of the effects of time on the invasion. Forecasts must also include components contributing to the\\u000a spread rate such as invasion stage and Allee effects. There are several different analysis techniques available for spatial\\u000a models and forecasting, and the appropriate technique

Catherine S. Jarnevich; Thomas J. Stohlgren

247

Invasive Species and Food Security  

Microsoft Academic Search

\\u000a This chapter defines invasive species, noting that they may arrive in new areas either intentionally or unintentionally, and\\u000a it discusses their economic and non-economic effects. It provides examples of plant, insect, fish, and other invasive species,\\u000a which have impacts on food production. Immediate environmental stressors, such as socio-economic change, cause the unintentional\\u000a transmission of invasive species. In recent years, improved

Jenifer Huang McBeath; Jerry McBeath

248

Dietary Flexibility Aids Asian Earthworm Invasion in North American Forests  

EPA Science Inventory

On a local scale, invasiveness of introduced species and invasibility of habitats together determine invasion success. A key issue in invasion ecology has been how to quantify the contribution of species invasiveness and habitat invasibility separately. Conventional approaches, s...

249

Invasibility and Wildlife Conservation: Invasive Species on Nature Reserves  

Microsoft Academic Search

Nature reserves are often considered to be assemblages of species in natural or semi-natural communities. However, in many parts of the world they also contain exotic species that interact with the native flora and fauna. An International Working Group has been endeavouring to understand the management of invasive species in natural landscapes. Data for four invasive species within the British

M. B. Usher

1986-01-01

250

The Invasive Species Forecasting System  

Microsoft Academic Search

The Invasive Species Forecasting System provides computational support for the generic work processes found in many regional-scale ecosystem modeling applications. ISFS has been designed specifically to help resource managers understand the potential distribution of invasive terrestrial plant species. Decision support tools built using ISFS allow a user to load point occurrence field sample data for a plant species of interest

John L Schnase; Roger Gill; Peter Ma

2009-01-01

251

Spread dynamics of invasive species  

PubMed Central

Species invasions are a principal component of global change, causing large losses in biodiversity as well as economic damage. Invasion theory attempts to understand and predict invasion success and patterns of spread. However, there is no consensus regarding which species or community attributes enhance invader success or explain spread dynamics. Experimental and theoretical studies suggest that regulation of spread dynamics is possible; however, the conditions for its existence have not yet been empirically demonstrated. If invasion spread is a regulated process, the structure that accounts for this regulation will be a main determinant of invasion dynamics. Here we explore the existence of regulation underlying changes in the rate of new site colonization. We employ concepts and analytical tools from the study of abundance dynamics and show that spread dynamics are, in fact, regulated processes and that the regulation structure is notably consistent among invasions occurring in widely different contexts. We base our conclusions on the analysis of the spread dynamics of 30 species invasions, including birds, amphibians, fish, invertebrates, plants, and a virus, all of which exhibited similar regulation structures. In contrast to current beliefs that species invasions are idiosyncratic phenomena, here we provide evidence that general patterns do indeed exist.

Arim, Matias; Abades, Sebastian R.; Neill, Paula E.; Lima, Mauricio; Marquet, Pablo A.

2006-01-01

252

Integrated assessment of biological invasions  

Technology Transfer Automated Retrieval System (TEKTRAN)

As the main annalists of the ecological and economic impacts of invasions on ecosystems around the world, ecologists should be able to provide information that can guide management practices. Managers often want to know about the potential for invasion of specific organisms in the sites under their ...

253

Meeting the Invasive Species Challenge.  

National Technical Information Service (NTIS)

Invasive species affect each of our lives, all regions of the U.S., and every nation in the world. Society pays a great price for invasive species costs measured not just in dollars, but also in unemployment, damaged goods and equipment, power failures, f...

2001-01-01

254

Soma size distinguishes projection neurons from neurokinin 1 receptor-expressing interneurons in lamina I of the rat lumbar spinal dorsal horn  

PubMed Central

Lamina I of the spinal dorsal horn contains neurons that project to various brain regions, and ?80% of these projection cells express the neurokinin 1 receptor (NK1r), the main receptor for substance P. Two populations of NK1r-immunoreactive neurons have been identified in lamina I: small weakly immunoreactive cells and large cells with strong immunolabelling [Cheunsuang O and Morris R (2000) Neuroscience 97:335–345]. The main aim of this study was to test the hypothesis that the large cells are projection neurons and that the small cells are interneurons. Projection neurons were identified by injection of tracers into the caudal ventrolateral medulla and lateral parabrachial area, and this was combined with immunostaining for NK1r. We found a bimodal size distribution for NK1r-immunoreactive neurons. The small cells (with somatic cross-sectional areas <200 ?m2) showed weak immunoreactivity, while immunostaining intensity was variable among the large cells. Virtually all (99%) of the immunoreactive cells with soma areas >200 ?m2 were retrogradely labelled, while only 10% of retrogradely labelled cells were smaller than this. Soma sizes of retrogradely labelled neurons that lacked NK1r did not differ from those of NK1r-expressing projection neurons. It has been suggested that a population of small pyramidal projection neurons that lack NK1r may correspond to cells activated by innocuous cooling, and we therefore assessed the morphology of retrogradely labelled cells that were not NK1r-immunoreactive. Fifteen percent of these were pyramidal, but these did not differ in size from pyramidal NK1r-immunoreactive projection neurons. These results confirm that large NK1r-immunoreactive lamina I neurons are projection cells, and suggest that the small cells are interneurons. Since almost all of the NK1r-immunoreactive cells with soma size >200 ?m2 were retrogradely labelled, cells of this type can be identified as projection cells in anatomical studies.

Al Ghamdi, K.S.; Polgar, E.; Todd, A.J.

2009-01-01

255

The BMPix and PEAK Tools: New Methods for Automated Laminae Recognition and Counting - Application to Glacial Varves From Antarctic Marine Sediment  

NASA Astrophysics Data System (ADS)

We present software-based tools for rapid and quantitative detection of sediment lamination. The BMPix tool extracts color and gray-scale curves from images at ultrahigh (pixel) resolution. The PEAK tool uses the gray-scale curve and performs, for the first time, fully automated counting of laminae based on three methods. The maximum count algorithm counts every bright peak of a couplet of two laminae (annual resolution) in a Gaussian smoothed gray-scale curve. The zero-crossing algorithm counts every positive and negative halfway-passage of the gray-scale curve through a wide moving average. Hence, the record is separated into bright and dark intervals (seasonal resolution). The same is true for the frequency truncation method, which uses Fourier transformation to decompose the gray-scale curve into its frequency components, before positive and negative passages are count. We applied the new methods successfully to tree rings and to well-dated and already manually counted marine varves from Saanich Inlet before we adopted the tools to rather complex marine laminae from the Antarctic continental margin. In combination with AMS14C dating, we found convincing evidence that the laminations from three Weddell Sea sites represent true varves that were deposited on sediment ridges over several millennia during the last glacial maximum (LGM). There are apparently two seasonal layers of terrigenous composition, a coarser-grained bright layer, and a finer-grained dark layer. The new tools offer several advantages over previous tools. The counting procedures are based on a moving average generated from gray-scale curves instead of manual counting. Hence, results are highly objective and rely on reproducible mathematical criteria. Since PEAK associates counts with a specific depth, the thickness of each year or each season is also measured which is an important prerequisite for later spectral analysis. Since all information required to conduct the analysis is displayed graphically, interactive optimization of the counting algorithms can be achieved quickly and conveniently.

Weber, M. E.; Reichelt, L.; Kuhn, G.; Thurow, J. W.; Ricken, W.

2009-12-01

256

BMPix and PEAK tools: New methods for automated laminae recognition and counting—Application to glacial varves from Antarctic marine sediment  

NASA Astrophysics Data System (ADS)

We present tools for rapid and quantitative detection of sediment lamination. The BMPix tool extracts color and gray scale curves from images at pixel resolution. The PEAK tool uses the gray scale curve and performs, for the first time, fully automated counting of laminae based on three methods. The maximum count algorithm counts every bright peak of a couplet of two laminae (annual resolution) in a smoothed curve. The zero-crossing algorithm counts every positive and negative halfway passage of the curve through a wide moving average, separating the record into bright and dark intervals (seasonal resolution). The same is true for the frequency truncation method, which uses Fourier transformation to decompose the curve into its frequency components before counting positive and negative passages. The algorithms are available at doi:10.1594/PANGAEA.729700. We applied the new methods successfully to tree rings, to well-dated and already manually counted marine varves from Saanich Inlet, and to marine laminae from the Antarctic continental margin. In combination with AMS14C dating, we found convincing evidence that laminations in Weddell Sea sites represent varves, deposited continuously over several millennia during the last glacial maximum. The new tools offer several advantages over previous methods. The counting procedures are based on a moving average generated from gray scale curves instead of manual counting. Hence, results are highly objective and rely on reproducible mathematical criteria. Also, the PEAK tool measures the thickness of each year or season. Since all information required is displayed graphically, interactive optimization of the counting algorithms can be achieved quickly and conveniently.

Weber, M. E.; Reichelt, L.; Kuhn, G.; Pfeiffer, M.; Korff, B.; Thurow, J.; Ricken, W.

2010-03-01

257

Populations of inhibitory and excitatory interneurons in lamina II of the adult rat spinal dorsal horn revealed by a combined electrophysiological and anatomical approach  

PubMed Central

Lamina II contains a large number of interneurons involved in modulation and transmission of somatosensory (including nociceptive) information. However, its neuronal circuitry is poorly understood due to the difficulty of identifying functional populations of interneurons. This information is important for understanding nociceptive processing and for identifying changes that underlie chronic pain. In this study, we compared morphology, neurotransmitter content, electrophysiological and pharmacological properties for 61 lamina II neurons recorded in slices from adult rat spinal cord. Morphology was related to transmitter content, since islet cells were GABAergic, while radial and most vertical cells were glutamatergic. However, there was considerable diversity among the remaining cells, some of which could not be classified morphologically. Transmitter phenotype was related to firing pattern, since most (18/22) excitatory cells, but few (2/23) inhibitory cells had delayed, gap or reluctant patterns, which are associated with A-type potassium (IA) currents. Somatostatin was identified in axons of 14/24 excitatory neurons. These had variable morphology, but most of those tested showed delayed-firing. Excitatory interneurons are therefore likely to contribute to pain states associated with synaptic plasticity involving IA currents. Although noradrenaline and serotonin evoked outward currents in both inhibitory and excitatory cells, somatostatin produced these currents only in inhibitory neurons, suggesting that its pro-nociceptive effects are mediated by disinhibition. Our results demonstrate that certain distinctive populations of inhibitory and excitatory interneuron can be recognised in lamina II. Combining this approach with identification of other neurochemical markers should allow further clarification of neuronal circuitry in the superficial dorsal horn.

Yasaka, Toshiharu; Tiong, Sheena Y.X.; Hughes, David I.; Riddell, John S.; Todd, Andrew J.

2010-01-01

258

Peyer's patch eosinophils: identification, characterization, and regulation by mucosal allergen exposure, interleukin-5, and eotaxin  

Microsoft Academic Search

The gastrointestinal immune system is traditionally thought to be composed of lymphocytes located within Peyer's patches and the lamina propria. We have recently reported that eosinophils also reside in the gastrointestinal tract during healthy states, in particular, within the lamina propria, and that these cells sub- stantially increase after oral allergen expo- sure. We now demonstrate the presence of eosinophils

Anil Mishra; Simon P. Hogan; Eric B. Brandt; Marc E. Rothenberg

259

Effects of cleavage by a disintegrin and metalloproteinase with thrombospondin motifs-4 on gene expression and protein content of versican and aggrecan in the digital laminae of horses with starch gruel-induced laminitis  

PubMed Central

Objective To determine whether increased gene expression of a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4) in laminae of horses with starch gruel– induced laminitis is accompanied by increased enzyme activity and substrate degradation. Sample Laminae from the forelimb hooves of 8 healthy horses and 17 horses with starch gruel–induced laminitis (6 at onset of fever, 6 at onset of Obel grade 1 lameness, and 5 at onset of Obel grade 3 lameness). Procedures Gene expression was determined by use of cDNA and real-time quantitative PCR assay. Protein expression and processing were determined via SDS-PAGE and quantitative western blotting. Protein distribution and abundance were determined via quantitative immunofluorescent staining. Results ADAMTS-4 gene expression was increased and that of versican decreased in laminitic laminae, compared with expression in healthy laminae. Catalytically active ADAMTS-4 also was increased in the tissue, as were ADAMTS-4–cleavage fragments of versican. Immunofluorescent analyses indicated that versican was depleted from the basal epithelia of laminae of horses at onset of Obel grade 3 lameness, compared with that in healthy laminae, and this was accompanied by regional separation of basal epithelial cells from the basement membrane. Aggrecan gene and protein expression were not significantly affected. Conclusions and Clinical Relevance Changes in gene and protein expression of ADAMTS-4 and versican in the basal epithelium of laminitic laminae indicated a fundamental change in the physiology of basal epithelial cells. This was accompanied by and may have caused detachment of these cells from the basement membrane.

Wang, Le; Pawlak, Erica; Johnson, Philip J.; Belknap, James K.; Alfandari, Dominique; Black, Samuel J.

2012-01-01

260

Transdiaphragmatic extension of invasive thymoma  

SciTech Connect

The initial and follow-up computed tomographic (CT) examinations of 19 patients with surgically proven invasive thymoma were reviewed; 10 have been previously reported. Transdiaphragmatic extension of tumor was observed in six (31.5%) of the 19 patients. Sites of infradiaphragmatic invasion included the right lateral liver surface, posterior pararenal space, left paraaortic region, perigastric soft tissue, and spinal canal. In the patient with known or suspected invasive thymoma, transdiaphragmatic extension is a common occurrence that requires routine CT imaging of the upper abdomen to avoid underestimating the extend of disease.

Scatarige, J.C.; Fishman, E.K.; Zerhouni, E.A.; Siegelman, S.S.

1985-01-01

261

Chick heart invasion assay.  

PubMed

Tumors are microecosystems in which a continuous cross talk between cancer cells and host cells decides on the invasive behavior of the tumor cell population as a whole (Mareel et al., Encyclopedia of cancer, San Diego, CA, Academic Press, 1997). Both compartments secrete activating and inhibitory factors that modulate activities such as cell-extracellular matrix (ECM) interaction, cell-cell adhesion, remodeling of the ECM, and cell motility. For this reason, confrontations of cancer cells with a living normal host tissue in organ culture have been introduced by several groups: Wolff and Schneider in France (Wolff and Schneider, C R S Soc Biol (Paris) 151:1291-1292, 1957), Easty and Easty in the United Kingdom (Easty and Easty, Nature 199:1104-1105, 1963), and Schleich in Germany (Schleich et al., J Natl Cancer Inst 56:221-237, 1976). Embryonic chick heart fragments in organ culture maintain many histological features of their tissue of origin: They are composed of myocytes, fibroblasts, and endothelial cells, and their ECM contains fibronectin, laminin, and several collagen types. Moreover, the fragments remain contractile, and this activity allows the monitoring of their functional integrity during organ culture. PMID:24092434

Bracke, Marc E; Parmar, Virinder S; Depass, Anthony L; Stevens, Christian V; Vanhoecke, Barbara W; Mareel, Marc M

2014-01-01

262

Invasive meningococcal disease.  

PubMed

Invasive meningococcal disease (IMD) is a major public health and continues to cause substantial mortality and morbidity. Serotype C is the most frequent in Brazil. The clinical spectrum of IMD is broad (meningitis, meningococcemia or both) and the clinical evolution may be unpredictable. Main features associated with mortality are: age higher than 50 years old, seizures, shock, and meningococcemia without meningitis. Blood cultures should be obtained immediately. Lumbar puncture can be performed without previous computed tomography scan (CT) in most cases. Clinical features can be useful to predic patients where an abnormal CT scan is likely. Cerebrospinal fluid (CSF) culture and Gram stain should always be required. Latex agglutination sensitivity is highly variable. Polymerase chain reaction is specially useful when other methods are negative or delayed. Usually ceftriaxone should not be delayed while awaiting CSF study or CT. Dexamethasone can be used in meningococcal meningitis. Early suspicion of IMD and antibiotic in primary care before hospitalization, rapid transportation to a hospital, and stabilization in an intensive-care unit has substantially reduced the case-fatality rate. Vaccines against serotypes A, C, W-135, and Y are available while vaccines against serotype B are expected. PMID:24141498

Strelow, Vanessa L; Vidal, Jose E

2013-09-01

263

Minimally invasive kidney transplantation.  

PubMed

Minimally invasive kidney transplantation (MIKT) procedures, starting with lymphocele fenestration and continuing with laparoscopic donor nephrectomy, have been performed in recipients since 2006. From November 2011 to May 2012, we performed 86 consecutive renal transplantation with 43 conventional kidney transplantations (COKT) and 43 MIKTs using an apendectomy like, 4 to 5-cm incision. There were no significant differences between the groups according to age, sex, body mass index, donor type, surgical side, donor kidney or artery number. Mean operative time in the MIKT group was 164.2 minutes versus 153.5 minutes in the COKT group. The cold ischemia times in MIKT and COKT groups were 60.8 and 63.3 minutes, respectively. The lengths of hospital stay, blood creatinine levels at postoperative days 7, 30, and 90, and the 90th day creatinine clearances were similar. In conclusion, considering that the complication rate was equal and the graft functions equal, MIKT seemed to be a safe method for renal transplantation. PMID:23622589

Kaçar, S; Ero?lu, A; Tilif, S; Güven, B

2013-04-01

264

The invasion paradox: reconciling pattern and process in species invasions.  

PubMed

The invasion paradox describes the co-occurrence of independent lines of support for both a negative and a positive relationship between native biodiversity and the invasions of exotic species. The paradox leaves the implications of native-exotic species richness relationships open to debate: Are rich native communities more or less susceptible to invasion by exotic species? We reviewed the considerable observational, experimental, and theoretical evidence describing the paradox and sought generalizations concerning where and why the paradox occurs, its implications for community ecology and assembly processes, and its relevance for restoration, management, and policy associated with species invasions. The crux of the paradox concerns positive associations between native and exotic species richness at broad spatial scales, and negative associations at fine scales, especially in experiments in which diversity was directly manipulated. We identified eight processes that can generate either negative or positive native-exotic richness relationships, but none can generate both. As all eight processes have been shown to be important in some systems, a simple general theory of the paradox, and thus of the relationship between diversity and invasibility, is probably unrealistic. Nonetheless, we outline several key issues that help resolve the paradox, discuss the difficult juxtaposition of experimental and observational data (which often ask subtly different questions), and identify important themes for additional study. We conclude that natively rich ecosystems are likely to be hotspots for exotic species, but that reduction of local species richness can further accelerate the invasion of these and other vulnerable habitats. PMID:17489447

Fridley, J D; Stachowicz, J J; Naeem, S; Sax, D F; Seabloom, E W; Smith, M D; Stohlgren, T J; Tilman, D; Von Holle, B

2007-01-01

265

Squamous cell carcinoma - invasive (image)  

MedlinePLUS

This irregular red nodule is an invasive squamous cell carcinoma (a form of skin cancer). Initial appearance, shown here, may be very similar to a noncancerous growth called a keratoacanthoma. Squamous cell cancers ...

266

Invasion of the zebra mussel  

NSDL National Science Digital Library

Zebra mussels were brought to North America in the ballast water of ships. Since 1988, the zebra mussels have pushed native freshwater mussels to near-extinction. The zebra mussel invasion is a great example of time delays.

Katie Hale (CSUF;Biological Sciences)

2007-07-08

267

Heart bypass surgery - minimally invasive  

MedlinePLUS

Minimally invasive direct coronary artery bypass; MIDCAB; Robot assisted coronary artery bypass; RACAB; Keyhole heart surgery ... your heart to stabilize it. You will receive medicine to slow the heart down.

268

Adaptive optics optical coherence tomography at 120,000 depth scans/s for non-invasive cellular phenotyping of the living human retina  

PubMed Central

This paper presents a successful combination of ultra-high speed (120,000 depth scans/s), ultra-high resolution optical coherence tomography with adaptive optics and an achromatizing lens for compensation of monochromatic and longitudinal chromatic ocular aberrations, respectively, allowing for non-invasive volumetric imaging in normal and pathologic human retinas at cellular resolution. The capability of this imaging system is demonstrated here through preliminary studies by probing cellular intraretinal structures that have not been accessible so far with in vivo, non-invasive, label-free imaging techniques, including pigment epithelial cells, micro-vasculature of the choriocapillaris, single nerve fibre bundles and collagenous plates of the lamina cribrosa in the optic nerve head. In addition, the volumetric extent of cone loss in two colour-blinds could be quantified for the first time. This novel technique provides opportunities to enhance the understanding of retinal pathogenesis and early diagnosis of retinal diseases.

Torti, Cristiano; Povazay, Boris; Hofer, Bernd; Unterhuber, Angelika; Carroll, Joseph; Ahnelt, Peter Kurt; Drexler, Wolfgang

2012-01-01

269

Biological Invasions by Marine Jellyfish  

Microsoft Academic Search

Comparatively little research has been conducted on the ecology of invasive organisms in marine ecosystems when balanced against\\u000a their terrestrial counterparts (Carlton and Geller 1993). Perhaps rates of invasions in marine systems are simply lower than\\u000a in other systems, but more likely lack of scrutiny, difficulty with taxonomic resolution, and unusual life-history characters\\u000a of marine organisms cause the vast majority

William M. Graham; Keith M. Bayha

270

RASCAL Is a New Human Cytomegalovirus-Encoded Protein That Localizes to the Nuclear Lamina and in Cytoplasmic Vesicles at Late Times Postinfection?  

PubMed Central

The products of numerous open reading frames (ORFs) present in the genome of human cytomegalovirus (CMV) have not been characterized. Here, we describe the identification of a new CMV protein localizing to the nuclear envelope and in cytoplasmic vesicles at late times postinfection. Based on this distinctive localization pattern, we called this new protein nuclear rim-associated cytomegaloviral protein, or RASCAL. Two RASCAL isoforms exist, a short version of 97 amino acids encoded by the majority of CMV strains and a longer version of 176 amino acids encoded by the Towne, Toledo, HAN20, and HAN38 strains. Both isoforms colocalize with lamin B in deep intranuclear invaginations of the inner nuclear membrane (INM) and in novel cytoplasmic vesicular structures possibly derived from the nuclear envelope. INM infoldings have been previously described as sites of nucleocapsid egress, which is mediated by the localized disruption of the nuclear lamina, promoted by the activities of viral and cellular kinases recruited by the lamina-associated proteins UL50 and UL53. RASCAL accumulation at the nuclear membrane required the presence of UL50 but not of UL53. RASCAL and UL50 also appeared to specifically interact, suggesting that RASCAL is a new component of the nuclear egress complex (NEC) and possibly involved in mediating nucleocapsid egress from the nucleus. Finally, the presence of RASCAL within cytoplasmic vesicles raises the intriguing possibility that this protein might participate in additional steps of virion maturation occurring after capsid release from the nucleus.

Miller, Matthew S.; Furlong, Wendy E.; Pennell, Leesa; Geadah, Marc; Hertel, Laura

2010-01-01

271

The defective nuclear lamina in Hutchinson-gilford progeria syndrome disrupts the nucleocytoplasmic Ran gradient and inhibits nuclear localization of Ubc9.  

PubMed

The mutant form of lamin A responsible for the premature aging disease Hutchinson-Gilford progeria syndrome (termed progerin) acts as a dominant negative protein that changes the structure of the nuclear lamina. How the perturbation of the nuclear lamina in progeria is transduced into cellular changes is undefined. Using patient fibroblasts and a variety of cell-based assays, we determined that progerin expression in Hutchinson-Gilford progeria syndrome inhibits the nucleocytoplasmic transport of several factors with key roles in nuclear function. We found that progerin reduces the nuclear/cytoplasmic concentration of the Ran GTPase and inhibits the nuclear localization of Ubc9, the sole E2 for SUMOylation, and of TPR, the nucleoporin that forms the basket on the nuclear side of the nuclear pore complex. Forcing the nuclear localization of Ubc9 in progerin-expressing cells rescues the Ran gradient and TPR import, indicating that these pathways are linked. Reducing nuclear SUMOylation decreases the nuclear mobility of the Ran nucleotide exchange factor RCC1 in vivo, and the addition of SUMO E1 and E2 promotes the dissociation of RCC1 and Ran from chromatin in vitro. Our data suggest that the cellular effects of progerin are transduced, at least in part, through reduced function of the Ran GTPase and SUMOylation pathways. PMID:21670151

Kelley, Joshua B; Datta, Sutirtha; Snow, Chelsi J; Chatterjee, Mandovi; Ni, Li; Spencer, Adam; Yang, Chun-Song; Cubeñas-Potts, Caelin; Matunis, Michael J; Paschal, Bryce M

2011-06-13

272

Plant invasions and extinction debts  

PubMed Central

Whether introduced species invasions pose a major threat to biodiversity is hotly debated. Much of this debate is fueled by recent findings that competition from introduced organisms has driven remarkably few plant species to extinction. Instead, native plant species in invaded ecosystems are often found in refugia: patchy, marginal habitats unsuitable to their nonnative competitors. However, whether the colonization and extinction dynamics of these refugia allow long-term native persistence is uncertain. Of particular concern is the possibility that invasive plants may induce an extinction debt in the native flora, where persistence over the short term masks deterministic extinction trajectories. We examined how invader impacts on landscape structure influence native plant persistence by combining recently developed quantitative techniques for evaluating metapopulation persistence with field measurements of an invaded plant community. We found that European grass invasion of an edaphically heterogeneous California landscape has greatly decreased the likelihood of the persistence of native metapopulations. It does so via two main pathways: (i) decreasing the size of native refugia, which reduces seed production and increases local extinction, and (ii) eroding the dispersal permeability of the matrix between refugia, which reduces their connectivity. Even when native plant extinction is the deterministic outcome of invasion, the time to extinction can be on the order of hundreds of years. We conclude that the relatively short time since invasion in many parts of the world is insufficient to observe the full impact of plant invasions on native biodiversity.

Gilbert, Benjamin; Levine, Jonathan M.

2013-01-01

273

The evolutionary consequences of biological invasions  

Microsoft Academic Search

A major challenge of invasion biology is the development of a predictive framework that prevents new invasions. This is inherently difficult because different biological character- istics are important at the different stages of invasion: opportunity\\/transport, establish- ment and spread. Here, we draw from recent research on a variety of taxa to examine the evolutionary causes and consequences of biological invasions.

ANDREW V. S UAREZ; NEIL D. T SUTSUI

2008-01-01

274

Predicting invasion success in complex ecological networks  

Microsoft Academic Search

A central and perhaps insurmountable challenge of invasion ecology is to predict which combinations of species and habitats most effectively promote and prevent biological invasions. Here, we integrate models of network structure and nonlinear population dynamics to search for potential generalities among trophic factors that may drive invasion success and failure. We simulate invasions where 100 different species attempt to

Tamara N. Romanuk; Yun Zhou; Ulrich Brose; Eric L. Berlow; Richard J. Williams; Neo D. Martinez

2009-01-01

275

Invasive shrub alters native forest amphibian communities  

Microsoft Academic Search

Although invasive plants can have transformative effects on native plant communities, studies of the consequences of plant invasion for native fauna are generally restricted to primary consumers. Here we investigate whether an invasive shrub, Lonicera maackii, impacts native amphibians and evaluate evidence for the role of invasive plant-induced alteration of forest understory microclimate as a mechanism driving amphibian responses to

James I. Watling; Caleb R. Hickman; John L. Orrock

2011-01-01

276

Invasibility or invasiveness? Effects of habitat, genotype, and their interaction on invasive Rhododendron ponticum populations  

Microsoft Academic Search

The extent and nature of biological invasions are mainly influenced by either the genotype of the invading species, the suitability\\u000a of the new habitat or by genotype-habitat interactions expressed in adaptations to the new environment. The relevance of these\\u000a factors was assessed for the invasive evergreen shrub Rhododendron ponticum. Habitat characteristics of soil, climate and community properties were analysed in

Alexandra Erfmeier; Helge Bruelheide

2010-01-01

277

Invasiveness, invasibility and the role of environmental stress in the spread of non-native plants  

Microsoft Academic Search

Invasion ecology, the study of how organisms spread in habitats to which they are not native, asks both about the invasiveness of species and the invasibility of habitats: Which species are most likely to become invasive? Which habitats are most susceptible to invasion? To set the stage for considering these questions with regard to plants, we offer a two-way classification

Peter Alpert; Elizabeth Bone; Claus Holzapfel

2000-01-01

278

Invasion of Distal Nephron Precursors Associates with Tubular Interconnection during Nephrogenesis  

PubMed Central

Formation of a functional renal network requires the interconnection of two epithelial tubes: the nephron, which arises from kidney mesenchyme, and the collecting system, which originates from the branching ureteric epithelium. How this connection occurs, however, is incompletely understood. Here, we used high-resolution image analysis in conjunction with genetic labeling of epithelia to visualize and characterize this process. Although the focal absence of basal lamina from renal vesicle stages ensures that both epithelial networks are closely apposed, we found that a patent luminal interconnection is not established until S-shaped body stages. Precursor cells of the distal nephron in the interconnection zone exhibit a characteristic morphology consisting of ill-defined epithelial junctional complexes but without expression of mesenchymal markers such as vimentin and Snai2. Live-cell imaging revealed that before luminal interconnection, distal cells break into the lumen of the collecting duct epithelium, suggesting that an invasive behavior is a key step in the interconnection process. Furthermore, loss of distal cell identity, which we induced by activating the Notch pathway, prevented luminal interconnection. Taken together, these data support a model in which establishing the distal identity of nephron precursor cells closest to the nascent collecting duct epithelium leads to an active cell invasion, which in turn contributes to a patent tubular interconnection between the nephron and collecting duct epithelia.

Kao, Robert M.; Vasilyev, Aleksandr; Miyawaki, Atsushi; Drummond, Iain A.

2012-01-01

279

Micropapillary Variant of Urothelial Carcinoma  

PubMed Central

Micropapillary carcinoma (MPC) of urinary tract is an uncommon variant of urothelial carcinoma with significant diagnostic and prognostic implications. Though MPC shows characteristic microscopic features, there exists interobserver variability and also it needs to be differentiated from the metastasis from other organs. The prognosis is generally poor, depending on the proportion of the micropapillary component in some reports. Early cystectomy in cases with only lamina propria invasion may be indicated according to recent studies. This review outlines the general features of this entity and briefly comments on the controversies and the recent development.

Kwon, Ghee Young; Ro, Jae Y.

2011-01-01

280

Trace element distribution in annual stalagmite laminae mapped by micrometer-resolution X-ray fluorescence: Implications for incorporation of environmentally significant species  

NASA Astrophysics Data System (ADS)

Stalagmite ER78, from Grotta di Ernesto cave in NE Italy displays clear annual lamination consistent with its shallow depth below a forest ecosystem subject to autumnal peaking of water infiltration. Synchrotron radiation scanning micro-X-ray fluorescence analyses of heavy elements at European Synchrotron Radiation Facility beamline ID22, and light elements at ID21, with 1 3 ?m resolution has been combined with data from ion microprobe analyses to reveal chemical variability across the visible layers of these annual laminae. A series of elements display a symmetrical peak, centered around the thin, dark layer at the top of each lamina. The peak concentration is ordered Y > Zn, Cu and Pb > P and Br. This hierarchy is thought to reflect the selectivity of transport of these elements, possibly by organic colloids flushed from the soil zone during autumn infiltration. Ion microprobe analysis indicates Na and F also increase, as does H, the latter reflecting increased microporosity. Sr displays a trough around the dark and thin autumn layer implying that its incorporation may be limited by competition with other elements. Mg and S show a different pattern of annual variation and Fe displays none. The trace metals, Br and Y display peak abundance in the early 20th century, which appears to reflect a period of tree-felling rather than a climatic anomaly. The results demonstrate the power of the high spatial resolution and low detection limits of the synchrotron technique, and its ability to produce quantitative maps that allow distinction of layered structure from that of isolated particles, or irregular inhomogeneities.

Borsato, Andrea; Frisia, Silvia; Fairchild, Ian J.; Somogyi, Andrea; Susini, Jean

2007-03-01

281

Induction of thermal hyperalgesia and synaptic long-term potentiation in the spinal cord lamina I by TNF-? and IL-1? is mediated by glial cells.  

PubMed

Long-term potentiation (LTP) of synaptic strength in nociceptive pathways is a cellular model of hyperalgesia. The emerging literature suggests a role for cytokines released by spinal glial cells for both LTP and hyperalgesia. However, the underlying mechanisms are still not fully understood. In rat lumbar spinal cord slices, we now demonstrate that conditioning high-frequency stimulation of primary afferents activated spinal microglia within <30 min and spinal astrocytes within ~2 s. Activation of spinal glia was indispensible for LTP induction at C-fiber synapses with spinal lamina I neurons. The cytokines interleukin-1? (IL-1?) and tumor necrosis factor-? (TNF-?), which are both released by activated glial cells, were individually sufficient and necessary for LTP induction via redundant pathways. They differentially amplified 2-amino-3-(3-hydroxy-5-methyl-isoxazol-4-yl)-propanoic acid receptor-mediated and N-methyl-D-aspartic acid receptor-mediated synaptic currents in lamina I neurons. Unexpectedly, the synaptic effects by IL-1? and TNF-? were not mediated directly via activation of neuronal cytokine receptors, but rather, indirectly via IL-1 receptors and TNF receptors being expressed on glial cells in superficial spinal dorsal horn. Bath application of IL-1? or TNF-? led to the release profiles of pro-inflammatory and anti-inflammatory cytokines, chemokines, and growth factors, which overlapped only partially. Heat hyperalgesia induced by spinal application of either IL-1? or TNF-? in naive animals also required activation of spinal glial cells. These results reveal a novel, decisive role of spinal glial cells for the synaptic effects of IL-1? and TNF-? and for some forms of hyperalgesia. PMID:23575851

Gruber-Schoffnegger, Doris; Drdla-Schutting, Ruth; Hönigsperger, Christoph; Wunderbaldinger, Gabriele; Gassner, Matthias; Sandkühler, Jürgen

2013-04-10

282

Utility of bioassays (lettuce, red clover, red fescue, Microtox, MetSTICK, Hyalella, bait lamina) in ecological risk screening of acid metal (Zn) contaminated soil.  

PubMed

The objective of this study was to assess selected bioassays and ecological screening tools for their suitability in a weight of evidence risk screening process of acidic metal contaminated soil. Intact soil cores were used for the tests, which minimizes changes in pH and metal bioavailability that may result from homogenization and drying of the soil. Soil cores were spiked with ZnCl(2) or CaCl(2). Leachate collected from the soil cores was used to account for the exposure pathways through pore water and groundwater. Tests assessed included MetSTICK in soil cores and Microtox in soil leachate, lettuce (Lactuca sativa), red fescue (Festuca rubra) and red clover (Trifolium pratense) in the soil cores and lettuce and red clover in soil leachate, Hyallella azteca in soil leachate, and an ecological soil function test using Bait Lamina in soil cores. Microtox, H. azteca, lettuce and red fescue showed higher sensitivity to low pH than to Zn concentrations and are therefore not recommended as tests on intact acidic soil cores and soil leachate. The Bait Lamina test appeared sensitive to pH levels below 3.7 but should be investigated further as a screening tool in less acidic soils. Among the bioassays, the MetSTICK and the T. pratense bioassays in soil cores were the most sensitive to Zn, with the lowest nominal NOEC of 200 and 400mg Zn/kg d.w., respectively. These bioassays were also tolerant of low pH, which make them suitable for assessing hazards of metal contaminated acid soils. PMID:22444727

Chapman, E Emily V; Hedrei Helmer, Stephanie; Dave, Göran; Murimboh, John D

2012-03-22

283

Evolutionary origins of invasive populations  

PubMed Central

What factors shape the evolution of invasive populations? Recent theoretical and empirical studies suggest that an evolutionary history of disturbance might be an important factor. This perspective presents hypotheses regarding the impact of disturbance on the evolution of invasive populations, based on a synthesis of the existing literature. Disturbance might select for life-history traits that are favorable for colonizing novel habitats, such as rapid population growth and persistence. Theoretical results suggest that disturbance in the form of fluctuating environments might select for organismal flexibility, or alternatively, the evolution of evolvability. Rapidly fluctuating environments might favor organismal flexibility, such as broad tolerance or plasticity. Alternatively, longer fluctuations or environmental stress might lead to the evolution of evolvability by acting on features of the mutation matrix. Once genetic variance is generated via mutations, temporally fluctuating selection across generations might promote the accumulation and maintenance of genetic variation. Deeper insights into how disturbance in native habitats affects evolutionary and physiological responses of populations would give us greater capacity to predict the populations that are most likely to tolerate or adapt to novel environments during habitat invasions. Moreover, we would gain fundamental insights into the evolutionary origins of invasive populations.

Lee, Carol Eunmi; Gelembiuk, Gregory William

2008-01-01

284

Advertising and Invasion of Privacy.  

ERIC Educational Resources Information Center

|The right of privacy as it relates to advertising and the use of a person's name or likeness is discussed in this paper. After an introduction that traces some of the history of invasion of privacy in court decisions, the paper examines cases involving issues such as public figures and newsworthy items, right of privacy waived, right of privacy…

Rohrer, Daniel Morgan

285

THE PERIODIC INVASIONS OF GOSHAWKS  

Microsoft Academic Search

We watched for Goshawk migration each autumn in the years 1950-74. Two major invasions, composed largely of adults, were seen, one in 1962 and 1963 and the other in 1972 and 1973. The 1972 southward movement was probably the greatest in history. Comparisons of in- terannual fluctuations in age and sex ratios with those derived from a model population strongly

HELMUT C. MUELLER; DANIEL D. BERGER; GEORGE ALLEZ

1977-01-01

286

Biological Warfare in Invasive Plants  

Technology Transfer Automated Retrieval System (TEKTRAN)

Alliaria petiolata (garlic mustard) is an invasive species in temperate forests throughout North America that has led to a decrease in species diversity and alterations in nutrient cycling. Garlic mustard produces an arsenal of secondary chemicals in the glucosinolate family that have strong biocid...

287

Real-time, in vivo analysis of malaria ookinete locomotion and mosquito midgut invasion.  

PubMed

Invasion of the Anopheles mosquito midgut by the Plasmodium ookinete is a critical step in the malaria transmission cycle. We have generated a fluorescent P. berghei transgenic line that expresses GFP in the ookinete and oocyst stages, and used it to perform the first real-time analysis of midgut invasion in the living mosquito as well as in explanted intact midguts whose basolateral plasma membranes were vitally stained. These studies permitted detailed analysis of parasite motile behaviour in the midgut and cell biological analysis of the invasion process. Throughout its journey, the ookinete displays distinct modes of motility: stationary rotation, translocational spiralling and straight-segment motility. Spiralling is based on rotational motility combined with translocation steps and changes in direction, which are achieved by transient attachments of the ookinete's trailing end. As it moves from the apical to the basal side of the midgut epithelium, the ookinete uses a predominant intracellular route and appears to glide on the membrane in foldings of the basolateral domain. However, it traverses serially the cytoplasm of several midgut cells before entering and migrating through the basolateral intercellular space to access the basal lamina. The invaded cells commit apoptosis, and their expulsion from the epithelium invokes wound repair mechanisms including extensive lamellipodia crawling. A 'hood' of lamellipodial origin, provided by the invaded cell, covers the ookinete during its egress from the epithelium. The flexible ookinete undergoes shape changes and temporary constrictions associated with passage through the plasma membranes. Similar observations were made in both A. gambiae and A. stephensi, demonstrating the conservation of P. berghei interactions with these vectors. PMID:15186403

Vlachou, Dina; Zimmermann, Timo; Cantera, Rafael; Janse, Chris J; Waters, Andrew P; Kafatos, Fotis C

2004-07-01

288

Cardiac Output Assessed by Invasive and Minimally Invasive Techniques  

PubMed Central

Cardiac output (CO) measurement has long been considered essential to the assessment and guidance of therapeutic decisions in critically ill patients and for patients undergoing certain high-risk surgeries. Despite controversies, complications and inherent errors in measurement, pulmonary artery catheter (PAC) continuous and intermittent bolus techniques of CO measurement continue to be the gold standard. Newer techniques provide less invasive alternatives; however, currently available monitors are unable to provide central circulation pressures or true mixed venous saturations. Esophageal Doppler and pulse contour monitors can predict fluid responsiveness and have been shown to decrease postoperative morbidity. Many minimally invasive techniques continue to suffer from decreased accuracy and reliability under periods of hemodynamic instability, and so few have reached the level of interchangeability with the PAC.

Lee, Allison J.; Cohn, Jennifer Hochman; Ranasinghe, J. Sudharma

2011-01-01

289

THE POPULATION BIOLOGY OF INVASIVE SPECIES  

Microsoft Academic Search

? Abstract Contributions from the field of population biology hold promise for understanding and managing invasiveness; invasive species also offer excellent oppor- tunities to study basic processes in population biology. Life history studies and demo- graphic models may be valuable for examining the introduction of invasive species and identifying life history stages where management will be most effective. Evolution- ary

Ann K. Sakai; Fred W. Allendorf; Jodie S. Holt; David M. Lodge; Jane Molofsky; Syndallas Baughman; Robert J. Cabin; Joel E. Cohen; Norman C. Ellstrand; David E. McCauley; Pamela O'Neil; Ingrid M. Parker; John N. Thompson; Stephen G. Weller

2001-01-01

290

INVASIVE SPECIES MANAGEMENT AND RESEARCH USING GIS  

Microsoft Academic Search

Geographical Information Systems (GIS) are powerful tools in the field of invasive species management. GIS can be used to create potential distribution maps for all manner of taxa, including plants, animals, and diseases. GIS also performs well in the early detection and rapid assessment of invasive species. Here, we used GIS applications to investigate species richness and invasion patterns in

Tracy Holcombe; Thomas J. Stohlgren; Catherine Jarnevich

2007-01-01

291

Community disassembly by an invasive species  

Microsoft Academic Search

Invasive species pose serious threats to community structure and ecosystem function worldwide. The impacts of invasive species can be more pervasive than simple reduction of species numbers. By using 7 years of data in a biological preserve in northern California, we documented the disassembly of native ant communities during an invasion by the Argentine ant. In sites without the Argentine

Nathan J. Sanders; Nicholas J. Gotelli; Nicole E. Heller; Deborah M. Gordon

2003-01-01

292

Invasion Biology and Biological Control 1  

Microsoft Academic Search

Analysis of some current issues in invasion biology that relate to exotic pests illustrates the linkage between this discipline and biological control and reveals opportunities for invasion biologists and biological control workers to mutually advance their respective disciplines. Concepts such as the tens rule, early-stage subdectability, and long latency period from invasion to first detection should be viewed as working

L. E. Ehler

1998-01-01

293

The Landscape Ecology of Invasive Spread  

Microsoft Academic Search

Although habitat loss, fragmentation, and invasive species collectively pose the greatest threats to biodiversity, little theoretical or empirical research has addressed the effects of landscape structure—or spa- tial pattern more generally—on the spread of invasive species. Landscape ecology is the study of how spatial pattern affects ecological process. Thus, a landscape ecology of invasive spread involves understanding how spatial pattern,

2002-01-01

294

CONSERVATION PROGRAMS THAT PROMOTE INVASIVE SPECIES  

EPA Science Inventory

Invasive plant species are degrading the structure and function of ecosystems throughout the world. Although most state and federal conservation agencies in the U.S. attempt to reduce the impact of invasive species, some agency activities can contribute to the spread of invasive...

295

Biodiversity as a barrier to ecological invasion  

Microsoft Academic Search

Biological invasions are a pervasive and costly environmental problem that has been the focus of intense management and research activities over the past half century. Yet accurate predictions of community susceptibility to invasion remain elusive. The diversity resistance hypothesis, which argues that diverse communities are highly competitive and readily resist invasion, is supported by both theory and experimental studies conducted

Theodore A. Kennedy; Shahid Naeem; Katherine M. Howe; Johannes M. H. Knops; David Tilman; Peter Reich

2002-01-01

296

Invasive aspergillosis in an immunocompetent host  

PubMed Central

Aspergillosis is a common opportunistic fungal infection affecting the nose and paranasal sinuses. The disease presents in various forms ranging from non-invasive to invasive, destructive and allergic types. We report here a rare case of invasive aspergillosis in an immunocompetent host with the literature review.

Sethi, Preeti; Saluja, Ramandeep; Jindal, Navin; Singh, Virender

2012-01-01

297

The risk of establishment of aquatic invasive species: joining invasibility and propagule pressure  

PubMed Central

Invasive species are increasingly becoming a policy priority. This has spurred researchers and managers to try to estimate the risk of invasion. Conceptually, invasions are dependent both on the receiving environment (invasibility) and on the ability to reach these new areas (propagule pressure). However, analyses of risk typically examine only one or the other. Here, we develop and apply a joint model of invasion risk that simultaneously incorporates invasibility and propagule pressure. We present arguments that the behaviour of these two elements of risk differs substantially—propagule pressure is a function of time, whereas invasibility is not—and therefore have different management implications. Further, we use the well-studied zebra mussel (Dreissena polymorpha) to contrast predictions made using the joint model to those made by separate invasibility and propagule pressure models. We show that predictions of invasion progress as well as of the long-term invasion pattern are strongly affected by using a joint model.

Leung, Brian; Mandrak, Nicholas E

2007-01-01

298

The risk of establishment of aquatic invasive species: joining invasibility and propagule pressure.  

PubMed

Invasive species are increasingly becoming a policy priority. This has spurred researchers and managers to try to estimate the risk of invasion. Conceptually, invasions are dependent both on the receiving environment (invasibility) and on the ability to reach these new areas (propagule pressure). However, analyses of risk typically examine only one or the other. Here, we develop and apply a joint model of invasion risk that simultaneously incorporates invasibility and propagule pressure. We present arguments that the behaviour of these two elements of risk differs substantially--propagule pressure is a function of time, whereas invasibility is not--and therefore have different management implications. Further, we use the well-studied zebra mussel (Dreissena polymorpha) to contrast predictions made using the joint model to those made by separate invasibility and propagule pressure models. We show that predictions of invasion progress as well as of the long-term invasion pattern are strongly affected by using a joint model. PMID:17711834

Leung, Brian; Mandrak, Nicholas E

2007-10-22

299

Laboratory diagnosis of invasive candidiasis.  

PubMed Central

Severe infections due to Candida species have become more frequent during the past two decades because of the increasing numbers of immunosuppressed patients being treated in our hospitals. Distinguishing colonization from invasive disease requires knowledge of the pathogenetic mechanisms leading to invasion. To assist the clinician in therapeutic decisions, clinical microbiologists should identify to species Candida organisms isolated from immunosuppressed patients. Quantitative or semiquantitative cultures of urine, burn tissues, intravascular catheter tips, and bronchoalveolar lavage specimens may provide useful information. Immunofluorescent staining of certain specimens can enhance diagnostic yield. The lysis-centrifugation blood culture technique offers some advantages over traditional broth techniques in detecting Candida fungemia. Antibody testing is of limited diagnostic value in highly immunosuppressed patients. Developing simple and reliable tests for detecting antigens or metabolites of Candida spp. in the sera of infected patients has proven difficult. Methods for typing Candida albicans are evolving. Typing should prove useful for studying the epidemiology of candidiasis in hospitalized patients. Images

Jones, J M

1990-01-01

300

Human mobility and epidemic invasion  

NASA Astrophysics Data System (ADS)

The current H1N1 influenza pandemic is just the latest example of how human mobility helps drive infectious diseases. Travel has grown explosively in the last decades, contributing to an emerging complex pattern of traffic flows that unfolds at different scales, shaping the spread of epidemics. Restrictions on people's mobility are thus investigated to design possible containment measures. By considering a theoretical framework in terms of reaction-diffusion processes, it is possible to study the invasion dynamics of epidemics in a metapopulation system with heterogeneous mobility patterns. The system is found to exhibit a global invasion threshold that sets the critical mobility rate below which the epidemic is contained. The results provide a general framework for the understanding of the numerical evidence from detailed data-driven simulations that show the limited benefit provided by travel flows reduction in slowing down or containing an emerging epidemic.

Colizza, Vittoria

2010-03-01

301

Why Ecology of Invasive Species?  

NSDL National Science Digital Library

Your students may think of ecologists as people who pick up trash and protest for a cleaner environment. In this manual, the term ecologist is used to refer to scientists who study ecology--that is, the study of relationships among organisms and between organisms and their physical environment. Through the readings, exercises, protocols, and research projects in Invasion Ecology, students will learn not only abut important ecological concepts, but also about how ecologists conduct research. Furthermore, they will learn how ecological science and research can be applied to solving a real-life environmental problem--the control of invasive species. This free selection also includes a bonus section--Inquiry and Ecology, the Table of Contents, and Introduction.

Krasny, Marianne E.; Team, The E.

2003-01-01

302

Epidemiology of Invasive Pulmonary Aspergillosis  

Microsoft Academic Search

\\u000a The epidemiology of IA, the major invasive mould infection in immunocompromised patients, has evolved over the last several\\u000a decades. During the 1990s, increasing morbidity and mortality from these infections, particularly amongst the increasing numbers\\u000a of patients being treated for haematological malignancies and those undergoing allogeneic haematopoietic stem cell transplantation,\\u000a became a universal experience in many tertiary care medical centres. Changes

Carol A. Kauffman; Nelson P. Nicolasora

303

Minimally invasive mitral valve surgery  

Microsoft Academic Search

Like many other surgical specialties, cardiac surgery is evolving toward more minimally invasive approaches. Mitral valve\\u000a surgery has been shown to be feasible and safe when performed through smaller incisions or with the aid of robotic manipulation.\\u000a Recent technologic advances allow complex mitral valve reconstruction to be carried out through these small incisions with\\u000a avoidance of a full sternotomy and

Sunil Panwar; Edward G. Soltesz

2008-01-01

304

Less-Invasive Cardiac Surgery  

Microsoft Academic Search

The history of cardiac surgery reflects a constant search by cardiac surgeons for safer and less-invasive ways to treat their\\u000a patients. Since Dr. F. John Lewis’s pioneering operation in 1952, followed by Dr. C. Walton Lillehei’s first successful series\\u000a of intracardiac defect repairs in the mid-1950s, cardiac surgery as a surgical subspecialty has expanded dramatically. Notably,\\u000a one of the most

Kenneth K. Liao

305

Alien Invasion: Invasive Species (title provided or enhanced by cataloger)  

NSDL National Science Digital Library

Using the example of the Eastern United States continental shelf, this lesson helps students understand how alien species enter non-native habitats, what problems are associated with these species, and what can be done about them. Students will be able to compare and contrast "alien species" and "invasive species," explain positive and negative impacts associated with the introduction of non-native species, and give a specific example of species that produces these impacts. They will also describe at least three ways in which species may be introduced into non-native environments and discuss actions that can be taken to mitigate negative impacts caused by non-native species.

306

The role of Schwann cells and basal lamina tubes in the regeneration of axons through long lengths of freeze-killed nerve grafts.  

PubMed

The ability of long acellular nerve grafts to support axonal regeneration was examined using inbred rats. Grafts (40 mm long) of tibial/plantar nerves were used either as live grafts or after freeze-drying to render the grafts acellular. The grafts were sutured to the proximal stump of severed tibial nerves in host animals which were then killed 1-12 weeks later. Axons rapidly regenerated through the living grafts but only extended 10-20 mm into the acellular grafts. This distance was achieved by 6 weeks and thereafter no significant further axonal extension occurred in the acellular grafts. A few naked axons lacking Schwann cell contact were identified in all acellular grafts, but became more numerous near the distal extent of axonal penetration into 6-12 week grafts. These axons contained large numbers of neurofilaments. When the distal 20 mm of 6 week acellular grafts (segments into which axons had not penetrated) were sutured to freshly severed tibial nerves, axons grew readily into the grafted tissue to a maximum distance of 9 mm. It is therefore likely that the limits to axonal regeneration through initially acellular grafts were set by factors intrinsic to the severed nerve. It is suggested that the limited migratory powers of Schwann cells may be one such factor. The concept that basal lamina tubes are not essential for axonal regeneration but may act as low resistance pathways for both axonal elongation and Schwann cell migration is discussed. PMID:2263316

Nadim, W; Anderson, P N; Turmaine, M

1990-10-01

307

Antarctic Crabs: Invasion or Endurance?  

PubMed Central

Recent scientific interest following the “discovery” of lithodid crabs around Antarctica has centred on a hypothesis that these crabs might be poised to invade the Antarctic shelf if the recent warming trend continues, potentially decimating its native fauna. This “invasion hypothesis” suggests that decapod crabs were driven out of Antarctica 40–15 million years ago and are only now returning as “warm” enough habitats become available. The hypothesis is based on a geographically and spatially poor fossil record of a different group of crabs (Brachyura), and examination of relatively few Recent lithodid samples from the Antarctic slope. In this paper, we examine the existing lithodid fossil record and present the distribution and biogeographic patterns derived from over 16,000 records of Recent Southern Hemisphere crabs and lobsters. Globally, the lithodid fossil record consists of only two known specimens, neither of which comes from the Antarctic. Recent records show that 22 species of crabs and lobsters have been reported from the Southern Ocean, with 12 species found south of 60°S. All are restricted to waters warmer than 0°C, with their Antarctic distribution limited to the areas of seafloor dominated by Circumpolar Deep Water (CDW). Currently, CDW extends further and shallower onto the West Antarctic shelf than the known distribution ranges of most lithodid species examined. Geological evidence suggests that West Antarctic shelf could have been available for colonisation during the last 9,000 years. Distribution patterns, species richness, and levels of endemism all suggest that, rather than becoming extinct and recently re-invading from outside Antarctica, the lithodid crabs have likely persisted, and even radiated, on or near to Antarctic slope. We conclude there is no evidence for a modern-day “crab invasion”. We recommend a repeated targeted lithodid sampling program along the West Antarctic shelf to fully test the validity of the “invasion hypothesis”.

Griffiths, Huw J.; Whittle, Rowan J.; Roberts, Stephen J.; Belchier, Mark; Linse, Katrin

2013-01-01

308

The Invasion of Exotic Plants  

NSDL National Science Digital Library

In a news announcement last week, US Secretary of the Interior Bruce Babbitt stated "the invasion of noxious weeds has created a level of destruction to America's environment and economy that is matched only by the damage caused by floods, earthquakes, wildfire, hurricanes and mudslides." Given recent media attention to the loss of native species, this week's In The News focuses on the spread of exotic plants across the globe, considered by some experts to be "the second-most important threat" behind habitat destruction. The eight resources discussed offer information on exotics, from local case studies to international examples, with comprehensive discussions of the topic.

Payne, Laura X.

1998-01-01

309

Heparan Sulfate Degradation: Relation to Tumor Invasive and Metastatic Properties of Mouse B16 Melanoma Sublines  

NASA Astrophysics Data System (ADS)

After transport in the blood and implantation in the microcirculation, metastatic tumor cells must invade the vascular endothelium and underlying basal lamina. Mouse B16 melanoma sublines were used to determine the relation between metastatic properties and the ability of the sublines to degrade enzymatically the sulfated glycosaminoglycans present in the extracellular matrix of cultured vascular endothelial cells. Highly invasive and metastatic B16 sublines degraded matrix glycosaminoglycans faster than did sublines of lower metastatic potential. The main products of this matrix degradation were heparan sulfate fragments. Intact B16 cells (or their cell-free homogenates) with a high potential for lung colonization degraded purified heparan sulfate from bovine lung at higher rates than did B16 cells with a poor potential for lung colonization. Analysis of the degradation fragments indicated that B16 cells have a heparan sulfate endoglycosidase. Thus the abilities of B16 melanoma cells to extravasate and successfully colonize the lung may be related to their capacities to degrade heparan sulfate in the walls of pulmonary blood vessels.

Nakajima, Motowo; Irimura, Tatsuro; di Ferrante, Daniela; di Ferrante, Nicola; Nicolson, Garth L.

1983-05-01

310

Predicting invasion success in complex ecological networks  

PubMed Central

A central and perhaps insurmountable challenge of invasion ecology is to predict which combinations of species and habitats most effectively promote and prevent biological invasions. Here, we integrate models of network structure and nonlinear population dynamics to search for potential generalities among trophic factors that may drive invasion success and failure. We simulate invasions where 100 different species attempt to invade 150 different food webs with 15–26 species and a wide range (0.06–0.32) of connectance. These simulations yield 11?438 invasion attempts by non-basal species, 47 per cent of which are successful. At the time of introduction, whether or not the invader is a generalist best predicts final invasion success; however, once the invader establishes itself, it is best distinguished from unsuccessful invaders by occupying a lower trophic position and being relatively invulnerable to predation. In general, variables that reflect the interaction between an invading species and its new community, such as generality and trophic position, best predict invasion success; however, for some trophic categories of invaders, fundamental species traits, such as having the centre of the feeding range low on the theoretical niche axis (for non-omnivorous and omnivorous herbivores), or the topology of the food web (for tertiary carnivores), best predict invasion success. Across all invasion scenarios, a discriminant analysis model predicted successful and failed invasions with 76.5 per cent accuracy for properties at the time of introduction or 100 per cent accuracy for properties at the time of establishment. More generally, our results suggest that tackling the challenge of predicting the properties of species and habitats that promote or inhibit invasions from food web perspective may aid ecologists in identifying rules that govern invasions in natural ecosystems.

Romanuk, Tamara N.; Zhou, Yun; Brose, Ulrich; Berlow, Eric L.; Williams, Richard J.; Martinez, Neo D.

2009-01-01

311

Impacts of Invasive Species on Ecosystem Services  

Microsoft Academic Search

The impacts of invasive species on ecosystem services have attracted worldwide attention. Despite the overwhelming evidence\\u000a of these impacts and a growing appreciation for ecosystem services, however, researchers and policymakers rarely directly\\u000a address the connection between invasions and ecosystem services.Various attempts have been made to address the ecosystem processes\\u000a that are affected by invasive species (e.g., Levine et al. 2003;

Heather Charles; Jeffrey S. Dukes

312

Immobilizing nitrogen to control plant invasion  

Microsoft Academic Search

Increased soil N availability may often facilitate plant invasions. Therefore, lowering N availability might reduce these\\u000a invasions and favor desired species. Here, we review the potential efficacy of several commonly proposed management approaches\\u000a for lowering N availability to control invasion, including soil C addition, burning, grazing, topsoil removal, and biomass\\u000a removal, as well as a less frequently proposed management approach

Laura G. Perry; Dana M. Blumenthal; Thomas A. Monaco; Mark W. Paschke; Edward F. Redente

2010-01-01

313

[Iron and invasive fungal infection.  

PubMed

Iron is an essential factor for both the growth and virulence of most of microorganisms. As a part of the innate (or nutritional) immune system, mammals have developed different mechanisms to store and transport this element in order to limit free iron bioavailability. To survive in this hostile environment, pathogenic fungi have specific uptake systems for host iron sources, one of the most important of which is based on the synthesis of siderophores-soluble, low-molecular-mass, high-affinity iron chelators. The increase in free iron that results from iron-overload conditions is a well-established risk factor for invasive fungal infection (IFI) such as mucormycosis or aspergillosis. Therefore, iron chelation may be an appealing therapeutic option for these infections. Nevertheless, deferoxamine -the first approved iron chelator- paradoxically increases the incidence of IFI, as it serves as a xeno-siderophore to Mucorales. On the contrary, the new oral iron chelators (deferiprone and deferasirox) have shown to exert a deleterious effect on fungal growth both in vitro and in animal models. The present review focuses on the role of iron metabolism in the pathogenesis of IFI and summarises the preclinical data, as well as the limited clinical experience so far, in the use of new iron chelators as treatment for mucormycosis and invasive aspergillosis. PMID:23684655

Alvarez, Florencio; Fernández-Ruiz, Mario; Aguado, José María

2013-05-14

314

Invasive group A streptococcus infections.  

PubMed

The late 1980s have witnessed the emergence of severe group A streptococcus (GAS) infection; shock, bacteremia, and acute respiratory distress syndrome are common features, and death has been associated with this infection in 30% of patients. Such infections have now been described in all parts of the United States, Europe, and Australia and have occurred predominantly in otherwise healthy adolescents and adults. The characteristic clinical and laboratory features of the streptococcal toxic shock syndrome include deep-seated infection associated with shock and multiorgan failure. Strains of GAS isolated from patients with invasive disease have been predominantly M types 1 and 3, which produce pyrogenic exotoxin A or B or both. In this report, the clinical and demographic features of streptococcal bacteremia, myositis, and necrotizing fasciitis will be presented and compared with those of streptococcal toxic shock syndrome. Current concepts of the pathogenesis of invasive streptococcal infection will also be presented in terms of the interaction between virulence factors of GAS and host defense mechanisms. Finally, new concepts for future treatment of serious streptococcal infections will be proposed. PMID:1571429

Stevens, D L

1992-01-01

315

Biology of invasive termites: a worldwide review.  

PubMed

The number of recognized invasive termite species has increased from 17 in 1969 to 28 today. Fourteen species have been added to the list in the past 44 years; 10 have larger distributions and 4 have no reported change in distribution, and 3 species are no longer considered invasive. Although most research has focused on invasive termites in urban areas, molecular identification methods have answered questions about certain species and found that at least six species have invaded natural forest habitats. All invasive species share three characteristics that together increase the probability of creating viable propagules: they eat wood, nest in food, and easily generate secondary reproductives. These characteristics are most common in two families, the Kalotermitidae and Rhinotermitidae (which make up 21 species on the invasive termite list), particularly in three genera, Cryptotermes, Heterotermes, and Coptotermes (which together make up 16 species). Although it is the largest termite family, the Termitidae (comprising 70% of all termite species) have only two invasive species, because relatively few species have these characteristics. Islands have double the number of invasive species that continents do, with islands in the South Pacific the most invaded geographical region. Most invasive species originate from Southeast Asia. The standard control methods normally used against native pest termites are also employed against invasive termites; only two eradication attempts, in South Africa and New Zealand, appear to have been successful, both against Coptotermes species. PMID:23020620

Evans, Theodore A; Forschler, Brian T; Grace, J Kenneth

2012-09-27

316

National Institute of Invasive Species Science (NIISS)  

USGS Publications Warehouse

The National Institute of Invasive Species Science (www.NIISS.org) is a consortium of governmental and nongovernmental partners, led by the U.S. Geological Survey (USGS), whose aim is to provide reliable information and advanced decision support tools for documenting, understanding, predicting, assessing, and addressing the threat of invasive species in the United States. The Institute coordinates the National Aeronautical and Space Administrationa??s (NASAa??s) Invasive Species National Application activities for the Department of the Interior and has al lead role in developing NASA-derived remote sensing and landscape-scale predictive modeling capabilities for the invasive species communitya?|

Stohlgren, Tom

2006-01-01

317

Minimally invasive approaches to the cervical spine.  

PubMed

Minimally invasive approaches and operative techniques are becoming increasingly popular for the treatment of cervical spine disorders. Minimally invasive spine surgery attempts to decrease iatrogenic muscle injury, decrease pain, and speed postoperative recovery with the use of smaller incisions and specialized instruments. This article explains in detail minimally invasive approaches to the posterior spine, the techniques for posterior cervical foraminotomy and arthrodesis via lateral mass screw placement, and anterior cervical foraminotomy. Complications are also discussed. Additionally, illustrated cases are presented detailing the use of minimally invasive surgical techniques. PMID:22082636

Celestre, Paul C; Pazmiño, Pablo R; Mikhael, Mark M; Wolf, Christopher F; Feldman, Lacey A; Lauryssen, Carl; Wang, Jeffrey C

2011-10-13

318

Hyperpolarization-activated and cyclic nucleotide-gated cation channel subunit 2 ion channels modulate synaptic transmission from nociceptive primary afferents containing substance P to secondary sensory neurons in laminae I-IIo of the rodent spinal dorsal horn  

Microsoft Academic Search

We have previously demonstrated that hyperpolarization-activated and cyclic nucleotide-gated cation channel subunit 2 (HCN2) is expressed by terminals of peptidergic nociceptive primary afferents in laminae I-IIo of the rat spinal dorsal horn. In this study, we investigated the possible neurotransmitters and postsynaptic targets of these HCN2-expressing primary afferent terminals in the superficial spinal dorsal horn by using immunocytochemical methods. We

Ildikó Papp; Krisztina Holló; Ferenc Erdélyi; Gábor Szabó; Miklós Antal

2006-01-01

319

Invasive exotic plants suffer less herbivory than non-invasive exotic plants  

PubMed Central

We surveyed naturally occurring leaf herbivory in nine invasive and nine non-invasive exotic plant species sampled in natural areas in Ontario, New York and Massachusetts, and found that invasive plants experienced, on average, 96% less leaf damage than non-invasive species. Invasive plants were also more taxonomically isolated than non-invasive plants, belonging to families with 75% fewer native North American genera. However, the relationship between taxonomic isolation at the family level and herbivory was weak. We suggest that invasive plants may possess novel phytochemicals with anti-herbivore properties in addition to allelopathic and anti-microbial characteristics. Herbivory could be employed as an easily measured predictor of the likelihood that recently introduced exotic plants may become invasive.

Cappuccino, Naomi; Carpenter, David

2005-01-01

320

Soil modification by invasive plants: effects on native and invasive species of mixed-grass prairies  

Microsoft Academic Search

Invasive plants are capable of modifying attributes of soil to facilitate further invasion by conspecifics and other invasive\\u000a species. We assessed this capability in three important plant invaders of grasslands in the Great Plains region of North America:\\u000a leafy spurge (Euphorbia esula), smooth brome (Bromus inermis) and crested wheatgrass (Agropyron cristatum). In a glasshouse, these three invasives or a group

Nicholas R. Jordan; Diane L. Larson; Sheri C. Huerd

2008-01-01

321

Coevolution between Native and Invasive Plant Competitors: Implications for Invasive Species Management  

Technology Transfer Automated Retrieval System (TEKTRAN)

Invasive species may establish in communities because they are better competitors than natives, but in order to remain community dominants, the competitive advantage of invasive species must be persistent. Native species that are not extirpated when highly invasive species are introduced are likely...

322

Gene profiles between non-invasive and invasive colon cancer using laser microdissection and polypeptide analysis  

Microsoft Academic Search

AIM: To explore the expression of differential gene expression profiles of target cell between non- invasive submucosal and invasive advanced tumor in colon carcinoma using laser microdissection (LMD) in combination with polypeptide analysis. METHODS: Normal colon tissue samples from 20 healthy individuals and 30 cancer tissue samples from early non-invasive colon cancer cells were obtained. The cells from these samples

Jin-Shui Zhu; Hua Guo; Ming-Quan Song; Guo-Qiang Chen; Qun Sun; Qiang Zhang

2008-01-01

323

Comparison of the Invasion of Crete and the Proposed Invasion in Malta.  

National Technical Information Service (NTIS)

In 1941, after the conquest of Yugoslavia and Greece, senior German military leaders were considering two airborne operations, one for the invasion of Crete and the other for the invasion of Malta. The invasion of Crete was executed from 20 May to 1 June ...

S. L. Kavanaugh

2006-01-01

324

Anterior thalamic lesions stop immediate early gene activation in selective laminae of the retrosplenial cortex: evidence of covert pathology in rats?  

PubMed

Lesions involving the anterior thalamic nuclei stopped immediate early gene (IEG) activity in specific regions of the rat retrosplenial cortex, even though there were no apparent cytoarchitectonic changes. Discrete anterior thalamic lesions were made either by excitotoxin (Experiment 1) or radiofrequency (Experiment 2) and, following recovery, the rats foraged in a radial-arm maze in a novel room. Measurements made 6-12 weeks postsurgery showed that, in comparison with surgical controls, the thalamic lesions produced the same, selective patterns of Fos changes irrespective of method. Granular (caudal granular cortex and rostral granular cortex), but not dysgranular (dysgranular cortex), retrosplenial cortex showed a striking loss of Fos-positive cells. While a loss of between 79 and 89% of Fos-positive cells was found in the superficial laminae, the deeper layers appeared normal. In Experiments 3 and 4, rats 9-10 months postsurgery were placed in an activity box for 30 min. Anterior thalamic lesions (Experiment 3) led to a pronounced IEG decrease of both Fos and zif268 throughout the retrosplenial cortex that now included the dysgranular area. These IEG losses were found even though the same regions appeared normal using standard histological techniques. Lesions of the postrhinal cortex (Experiment 4) did not bring about a loss of retrosplenial IEG activity even though this region is also reciprocally connected with the retrosplenial cortex. This selective effect of anterior thalamic damage upon retrosplenial activity may both amplify the disruptive effects of anterior thalamic lesions and help to explain the posterior cingulate hypoactivity found in Alzheimer's disease. PMID:15217385

Jenkins, Trisha A; Vann, Seralynne D; Amin, Eman; Aggleton, John P

2004-06-01

325

IOP-Induced Lamina Cribrosa Displacement and Scleral Canal Expansion: An Analysis of Factor Interactions Using Parameterized Eye-Specific Models  

PubMed Central

Purpose. To study the anterior–posterior lamina cribrosa deformation (LCD) and the scleral canal expansion (SCE) produced by an increase in IOP and identify the main factors and interactions that determine these responses in the monkey. Methods. Eye-specific baseline models of the LC and sclera of both eyes of three normal monkeys were constructed. Morphing techniques were used to generate 888 models with controlled variations in LC thickness, position and modulus (stiffness), scleral thickness and modulus, and scleral canal size and eccentricity. Finite element modeling was used to simulate an increase in IOP from 10 to 15 mm Hg. A two-level, full-factorial experimental design was used to select factor combinations and to determine the sensitivity of LCD and SCE to the eight factors, independently and in interaction. Results. LCD was between 53.6 ?m (posteriorly) and ?12.9 ?m (anteriorly), whereas SCE was between 0.5 and 15.2 ?m (all expansions). LCD was most sensitive to laminar modulus and position (24% and 21% of the variance in LCD, respectively), whereas SCE was most sensitive to scleral modulus and thickness (46% and 36% of the variance in SCE, respectively). There were also strong interactions between factors (35% and 7% of the variance in LCD and SCE, respectively). Conclusions. IOP-related LCD and SCE result from a complex combination of factors, including geometry and material properties of the LC and sclera. This work lays the foundation for interpreting the range of individual sensitivities to IOP and illustrates that predicting individual ONH response to IOP will require the measurement of multiple factors.

Sigal, Ian A.; Yang, Hongli; Roberts, Michael D.; Burgoyne, Claude F.

2011-01-01

326

Coupled molecular and 14C studies of microbial carbonate laminae formation and growth rates in dolomite stromatolites from Lagoa Salgada, Brazil  

NASA Astrophysics Data System (ADS)

This study investigates the application of radiocarbon (14C) measurements for age determination of the growth rate of modern dolomite stromalites from Lagoa Salgada, Rio de Janeiro, Brazil. Improved estimation of growth rates related with microbial processes during stromatolite formation may provide insights into ancient microbial carbonate sedimentation processes. Radiocarbon dating is frequently used to determine the age of carbonate materials, however, lagoonal carbonates often contain significant 14C content anomalies due to the "hard water effect." Lagoonal dissolved inorganic carbon (DIC) may sometimes achieve isotopic equilibrium with atmospheric CO2, and, in such cases, a coherent 14C chronology for paleo-carbonate precipitates may be established. However, more frequently, DIC does not show complete equilibrium with atmospheric CO2 due to major inputs of groundwater carbon. As a consequence, paleo-lagoonal carbonates often yield 14C ages which, after isotopic normalization, are older than those obtained, for instance, for time-equivalent terrestrial organic matter. Located on the Rio de Janeiro coastline, Lagoa Salgada is a unique environment, which has been studied for its particular carbonate sedimentation and development of dolomite stromatolites. This milieu provides an opportunity to test how Earth surface processes can change from normal carbonate sedimentation to the formation of microbialite structures (e.g., stromatolites, oncolites). In Lagoa Salgada, the formation of laminated structures involves diverse groups of microorganisms, which leads to the trapping of distinctive biomarkers or organic molecules as intracrystalline organic matter within the stromatolite laminae. We report on our research into the characterization of this trapped organic matter and the potential to utilize it to radiometrically determine the growth rate of these modern stromatolites. We also report 14C measurements of DIC from Lagoa Salgada.

Bahniuk Rumbelsperger, A. M.; McKenzie, J. A.; Montluçon, D.; Eglinton, T. I.; Matsuda, N.; França, A.; Vasconcelos, C.

2011-12-01

327

Spontaneous rupture of the internal elastic lamina in the rat: the manifestation of a genetically determined factor which may be linked to vascular fragility.  

PubMed

The spontaneous rupture of the internal elastic lamina (IEL) in various arteries occurs to different extents in different rat strains. We have quantified this phenomenon in the caudal and renal arteries and abdominal aorta in two normotensive inbred strains: the Brown Norway (BN) and Long Evans (LE) strains. At 5 weeks of age, BN rats of both sexes exhibited small numbers of interruptions in the IEL of the caudal artery, whereas LE rats did not. Postpubertal male and female BN rats presented large numbers of IEL interruptions in the caudal artery and significant numbers in the renal artery and abdominal aorta, whereas LE rats showed few in the caudal artery and none in the other arteries. Treatment with beta-aminopropionitrile (BAPN, an inhibitor of lysyl oxidase, the enzyme involved in the formation of cross-links in elastin and collagen) increased the formation of IEL ruptures in both strains in the caudal and renal artery and in the abdominal aorta in BN rats, but not in the abdominal aorta of LE rats. Apart from IEL ruptures, which were more prevalent in BN rats, no differences were observed in the ultrastructure of the aortic elastic fibers between the two strains, either in controls or in BAPN-treated rats. When male rats of both strains were made hypertensive by unilateral nephrectomy and administration of deoxycorticosterone and salt, mortality was more precocious in the BN strain although blood pressure was significantly higher in the BN strain at only one time point. The incidence of cerebrovascular hemorrhage was 48% in BN rats and 0% in LE rats. Hypertension increased the formation of ruptures in the IEL in some arteries - to a greater extent in the BN than in the LE rats. These results raise the possibility that the propensity to spontaneous rupture of the IEL, which is in part genetically determined, may reflect a latent form of vascular fragility which becomes significant in hypertension, resulting in poor survival and susceptibility to cerebrovascular accidents. PMID:2575918

Capdeville, M; Coutard, M; Osborne-Pellegrin, M J

1989-01-01

328

[Formation of disruptions of the internal elastica lamina, spontaneous and BAPN induced, in arteries of stroke-prone spontaneously hypertensive rats].  

PubMed

In the caudal and renal arteries of the male Wistar rat, interruptions in the internal elastic lamina (IEL) form spontaneously with age. beta-aminopropionitrile (BAPN), which is an inhibitor of the enzyme lysyl oxidase implicated in the synthesis of elastin, is able to induce in the young Wistar rat interruptions in the IEL which are morphologically very similar to those which form spontaneously. The spontaneously hypertensive strain (SHR), together with the Stroke-Prone spontaneously hypertensive substrain (SHR-SP) which is susceptible to cerebrovascular accidents early in life, have been selected from the Wistar strain. We have compared the incidence of IEL interruptions in caudal and renal arteries from SHR-SP aged 12 and 23 weeks with that observed in age-matched SHR. In addition, we have studied the effect of BAPN, administered from weaning during two weeks, on the formation of interruptions in the IEL in the caudal artery of SHR-SP, SHR and normotensive Wistar and WKY rats. Interruptions in the IEL were quantified by light microscopy on longitudinal semi-thin sections. Results showed that, in the caudal and renal arteries of SHR-SP, the number of interruptions in the IEL which form spontaneously was greater than in SHR. Moreover, BAPN administered between the age of 3 and 5 weeks led to the premature formation of a higher level of interruptions in the IEL in SHR-SP than in the 3 other strains of rat. The SHR was the strain which developed the least.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3116972

Coutard, M; Osborne-Pellegrin, M

1987-06-01

329

Isolation and characterization of a proteinaceous subnuclear fraction composed of nuclear matrix, peripheral lamina, and nuclear pore complexes from embryos of Drosophila melanogaster  

PubMed Central

Morphologically intact nuclei have been prepared from embryos of Drosophila melanogaster by a simple and rapid procedure. These nuclei have been further treated with high concentrations of DNase I and RNase A followed by sequential extraction with 2% Triton X-100 and 1 M NaCl to produce a structurally and biochemically distinct preparation designated Drosophila subnuclear fraction I (DSNF-I). As seen by phase- contrast microscopy, DSNF-I is composed of material which closely resembles unfractionated nuclei; residual internal nuclear structures including nucleolar remnants are clearly visible. By transmission electron microscopy, nuclear lamina, pore complexes, and a nuclear matrix are similarly identified. Biochemically, DSNF-I is composed almost entirely of protein (greater than 93%). SDS PAGE analysis reveals several major polypeptides; species at 174,000, 74,000, and 42,000 predominate. A polypeptide coincident with the Coomassie Blue- stainable 174-kdalton band has been shown by a novel technique of lectin affinity labeling to be a glycoprotein; a glycoprotein of similar or identical molecular weight has been found to be a component of nuclear envelope fractions isolated from the livers of rats, guinea pigs, opossums, and chickens. Antisera against several of the polypeptides in DSNF-I have been obtained from rabbits, and all of them show only little or no cross-reactivity with Drosophila cytoplasmic fractions. Initial results of immunocytochemical studies, while failing to positively localize either the 174- or 16-kdalton polypeptides, demonstrate a nuclear localization of the 74-kdalton antigen in all of several interphase cell types obtained from both Drosophila embryos and third-instar larvae.

1982-01-01

330

Fine-scale study of a thick stratospheric ozone lamina at the edge of the southern subtropical barrier: 2. Numerical simulations with coupled dynamics models  

NASA Astrophysics Data System (ADS)

The modeling of an event such as an ozone lamina requires reproducing both the global and the small scales. In this study we report on a specific model capable of resolving such scale issues: the COMMID model, which has been developed by coupling a mechanistic model, MSDOL, with a high-resolution advection model, MIMOSA. MSDOL, which is forced toward National Centers for Environmental Prediction (NCEP) reanalyses below 100 hPa, provides a consistent picture of the stratospheric large-scale circulation from which MIMOSA simulates the fine-scale filaments generated by breaking planetary waves in the stratosphere. To evaluate the performances of the model, we present results for a particular event of tropical-air intrusion at midlatitudes across the southern subtropical barrier observed in July 2000 and described in part 1 (Portafaix et al., 2003). The model is used to examine the contribution of each wave to the structure and the development of that event. The methodology consists in filtering the NCEP tropospheric forcing by zonal wave number and by phase speed. Our results show that mixing is significantly reduced precisely at the locations where the phase speeds of the filtered waves are close to the speed of the mean zonal wind, thus confirming the findings of previous studies. However, what is important here is that they validate the use of an approach based on the coupling of two models. The next step will consist in using the COMMID model in a more general way for further investigations of the impact of the tropospheric circulation on the isentropic transport in the stratosphere for climate sensitivity purposes.

Morel, BéAtrice; Bencherif, Hassan; Keckhut, Philippe; Portafaix, Thierry; Hauchecorne, Alain; Baldy, Serge

2005-09-01

331

Blood-Derived Human iPS Cells Generate Optic Vesicle-Like Structures with the Capacity to Form Retinal Laminae and Develop Synapses  

PubMed Central

Purpose. We sought to determine if human induced pluripotent stem cells (iPSCs) derived from blood could produce optic vesicle–like structures (OVs) with the capacity to stratify and express markers of intercellular communication. Methods. Activated T-lymphocytes from a routine peripheral blood sample were reprogrammed by retroviral transduction to iPSCs. The T-lymphocyte–derived iPSCs (TiPSCs) were characterized for pluripotency and differentiated to OVs using our previously published protocol. TiPSC-OVs were then manually isolated, pooled, and cultured en masse to more mature stages of retinogenesis. Throughout this stepwise differentiation process, changes in anterior neural, retinal, and synaptic marker expression were monitored by PCR, immunocytochemistry, and/or flow cytometry. Results. TiPSCs generated abundant OVs, which contained a near homogeneous population of proliferating neuroretinal progenitor cells (NRPCs). These NRPCs differentiated into multiple neuroretinal cell types, similar to OV cultures from human embryonic stem cells and fibroblast-derived iPSCs. In addition, portions of some TiPSC-OVs maintained their distinctive neuroepithelial appearance and spontaneously formed primitive laminae, reminiscent of the developing retina. Retinal progeny from TiPSC-OV cultures expressed numerous genes and proteins critical for synaptogenesis and gap junction formation, concomitant with the emergence of glia and the upregulation of thrombospondins in culture. Conclusions. We demonstrate for the first time that human blood–derived iPSCs can generate retinal cell types, providing a highly convenient donor cell source for iPSC-based retinal studies. We also show that cultured TiPSC-OVs have the capacity to self-assemble into rudimentary neuroretinal structures and express markers indicative of chemical and electrical synapses.

Phillips, M. Joseph; Wallace, Kyle A.; Dickerson, Sarah J.; Miller, Michael J.; Verhoeven, Amelia D.; Martin, Jessica M.; Wright, Lynda S.; Shen, Wei; Capowski, Elizabeth E.; Percin, E. Ferda; Perez, Enio T.; Zhong, Xiufeng; Canto-Soler, Maria V.; Gamm, David M.

2012-01-01

332

Absence of integrin ?1?1 results in transducin translocation defects, matrix accumulation in the basal lamina of the RPE, and photoreceptor cell degeneration in mice  

PubMed Central

Purpose The role of integrin/cell matrix interactions between the RPE and the basement membrane in retinal maintenance and function is not well characterized.In this study the functional importance of ?1?1 integrin for RPE cell homeostasis and retinal health was assessed by comparing ?1 integrin knockout mice with strain/age matched wild type mice. Methods Immunolocalization and western blot analysis of retinas and ARPE19 cells was performed to examine expression of ?1?1 integrin in the RPE. Retinal pathology was assessed by funduscopy, histology, and transmission electron microscopy. Progressive retinal damage was quantified by direct counting of rod photoreceptors. Light-induced translocation of arrestin and ?-transducin was documented by immunohistochemical analysis of retinal cryosections. Results Integrin ?1?1 localizes to the basal aspect of retinal pigment epithelial cells co-localizing with the basal lamina of the RPE. Integrin ?1 null mice have delayed onset progressive retinal degeneration associated with thickening of the basement membrane, dysmorphology of basal processes, synaptic malformations and funduscopic abnormalities. Integrin ?1-null mice display marked delay in transducin translocation compared to wild type mice following exposure to light in dark-adapted animals. Conclusions Collectively, these data suggest an essential role for ?1?1 integrin/basement membrane interactions in the RPE in basement membrane metabolism and translocation of transducin in photoreceptors. This is the first report describing evidence supporting an essential role for integrin/basement membrane interaction in the RPE. Further, this report demonstrates a direct link between integrin ?1?1 function in RPE and molecular defects in photoreceptor cell function before retinal pathology is apparent.

Peng, You-Wei; Zallocchi, Marisa; Meehan, Daniel T.; Delimont, Duane; Chang, Bo; Hawes, Norman; Wang, Weimin; Cosgrove, Dominic

2008-01-01

333

Identification of Genes Expressed in Malignant Cells That Promote Invasion  

Microsoft Academic Search

To systematically identify genes related to invasion a three-dimensional multicellular matrix invasion assay was used to classify human tumor cell lines as stromal invasion positive or stromal invasion negative. Cells from two of the primary cell types of the stromal compartment (endothelial cells (HMVEC) and myofibroblasts (HDF)) were assayed for invasion into tumor cell clusters (breast carcinoma, ovarian carcinoma, prostate

Jennifer Walter-Yohrling; Xiaohong Cao; Michele Callahan; William Weber; Sharon Morgenbesser; Stephen L. Madden; Clarence Wang; Beverly A. Teicher

2003-01-01

334

Lysophosphatidic acid and sphingosine-1-phosphate promote morphogenesis and block invasion of prostate cancer cells in three-dimensional organotypic models.  

PubMed

Normal prostate and some malignant prostate cancer (PrCa) cell lines undergo acinar differentiation and form spheroids in three-dimensional (3-D) organotypic culture. Acini formed by PC-3 and PC-3M, less pronounced also in other PrCa cell lines, spontaneously undergo an invasive switch, leading to the disintegration of epithelial structures and the basal lamina, and formation of invadopodia. This demonstrates the highly dynamic nature of epithelial plasticity, balancing epithelial-to-mesenchymal transition against metastable acinar differentiation. This study assessed the role of lipid metabolites on epithelial maturation. PC-3 cells completely failed to form acinar structures in delipidated serum. Adding back lysophosphatidic acid (LPA) and sphingosine-1-phosphate (S1P) rescued acinar morphogenesis and repressed invasion effectively. Blocking LPA receptor 1 (LPAR1) functions by siRNA (small interference RNA) or the specific LPAR1 inhibitor Ki16425 promoted invasion, while silencing of other G-protein-coupled receptors responsive to LPA or S1P mainly caused growth arrest or had no effects. The G-proteins G?(12/13) and G?(i) were identified as key mediators of LPA signalling via stimulation of RhoA and Rho kinases ROCK1 and 2, activating Rac1, while inhibition of adenylate cyclase and accumulation of cAMP may be secondary. Interfering with these pathways specifically impeded epithelial polarization in transformed cells. In contrast, blocking the same pathways in non-transformed, normal cells promoted differentiation. We conclude that LPA and LPAR1 effectively promote epithelial maturation and block invasion of PrCa cells in 3-D culture. The analysis of clinical transcriptome data confirmed reduced expression of LPAR1 in a subset of PrCa's. Our study demonstrates a metastasis-suppressor function for LPAR1 and G?(12/13) signalling, regulating cell motility and invasion versus epithelial maturation. PMID:21996742

Härmä, V; Knuuttila, M; Virtanen, J; Mirtti, T; Kohonen, P; Kovanen, P; Happonen, A; Kaewphan, S; Ahonen, I; Kallioniemi, O; Grafström, R; Lötjönen, J; Nees, M

2011-09-26

335

Immunotherapy against invasive mold infections.  

PubMed

Invasive infections due to filamentous fungi, such as Aspergillus spp., Zygomycetes, Scedosporium and Fusarium spp., cause significant morbidity and mortality in immunocompromised patients with hematological malignancies, recipients of hematopoietic stem cell transplants and those with chronic granulomatous disease. Despite antifungal therapy, the outcome is often unfavorable in these patients; immune restoration is considered as the cornerstone of successful treatment. Important aspects of human immune response against fungi include effective innate immune response expressed as effective phagocytic functions and a balance between proinflammatory and regulatory adaptive immune responses. A number of immunomodulatory approaches, including the administration of enhancing cytokines, adoptive transfer of pathogen-specific T lymphocytes and granulocyte transfusions have been investigated as adjunctive treatments against serious mold infections. Despite encouraging in vitro and in vivo data, current clinical evidence is not sufficient to allow firm recommendations on the use of these immunomodulatory modalities in serious mold infections. PMID:22150004

Antachopoulos, Charalampos; Katragkou, Aspasia; Roilides, Emmanuel

2012-01-01

336

papillomavirus DNA in invasive vulvar carcinoma  

Microsoft Academic Search

Received 15 July 2003 Abstract Objective. The present study investigates the influence of lymph node pathological features and HPV DNA status on the prognosis of vulvar invasive tumors. Methods. This study includes 184 consecutive cases of primary invasive squamous cell carcinoma of the vulva treated by radical surgery from 1975 to 1992, in Sao Paulo, Brazil. Clinical follow-up data was

Alvaro P. Pinto; Nicolas F. Schlecht; Javier Pintos; Jane Kaiano; Eduardo L. Franco; Christopher P. Crum; Luisa L. Villa

337

[Parkinson's disease - the future of invasive therapy].  

PubMed

For the treatment of Parkinson's disease invasive therapies have a long tradition. Deep brain stimulation is a well-established treatment option for the treatment of advanced Parkinson's disease with fluctuations. Further promising interventions for invasive therapy of Parkinson's disease are transplantation of foetal cells and stem cells, gene therapy and the use of duo-dopa and apomorhine. PMID:20195935

Deuschl, G

2010-03-01

338

Landscape Determinants of Nonindigenous Fish Invasions  

Microsoft Academic Search

Much has been written about the influence of exotic or nonindigenous species on natural habitats and communities of organisms, but little is known of the physical or biological conditions that lead to successful invasion of native habitats and communities by exotics. We studied invasivity factors in headwater streams of the Susquehanna River West Branch, which drains portions of the northern

Robert M. Ross; William A. Lellis; Randy M. Bennett; Connie S. Johnson

2001-01-01

339

Invasion Waves in Populations with Excitable Dynamics  

Microsoft Academic Search

Whilst the most obvious mechanism for a biological invasion is the occupation of a new territory as a result of direct ingress by individuals of the invading population, a more subtle “invasion” may occur without significant motion of invading individuals if the population dynamics in a predator prey scenario has an “excitable” character. Here, “excitable” means that a local equilibrium

J. Brindley; V. H. Biktashev; M. A. Tsyganov

2005-01-01

340

Woody Plant Invasion in Relictual Grasslands  

Microsoft Academic Search

Invasion by alien plants is one of the greatest and most widely distributed causes of man-made changes in ecosystems. One of its most conspicuous variants is the invasion of natural grasslands by exotic trees, which not only means the addition of new taxa to the native biota, but also the introduction of completely new life-forms. In Argentina, the Pampean plain

S. M. Zalba; C. B. Villamil

2002-01-01

341

Integrating Invasive Species Prevention and Control Policies  

Microsoft Academic Search

Programs and policies to minimize the threat of, or mitigate the damages from, invasive species work best if designed in concert with each other. Whether program emphasis should be on prevention or control depends on the biological characteristics and size of the invasive species population, ecological characteristics of invaded ecosystems, the cost and efficacy of prevention measures relative to control

Michael J. Livingston; Craig D. Osteen

2008-01-01

342

Optimal planning for minimally invasive surgical robots  

Microsoft Academic Search

Minimally invasive surgery (MIS) is an increasingly important approach in many specialties, where robots are poised to play an important role in displacing the limits set to such techniques through increased precision and dexterity. However, the potential of robotically assisted minimally invasive surgery (RMIS) is still far from being fully exploited because of the newness of the approach. One of

Louaï Adhami; Ève Coste-Manière

2003-01-01

343

Ecological and evolutionary consequences of coastal invasions  

Microsoft Academic Search

Although coastal estuarine and marine systems are among the most heavily invaded systems in the world, the study of nonindigenous species in these systems has, historically, lagged behind that of terrestrial and freshwater systems. However, in the past decade, a rapid increase in studies of coastal invasions has provided important insight into the invasion process in these systems and how

Edwin Grosholz

2002-01-01

344

How trade politics affect invasive species control  

Microsoft Academic Search

Trade has become the main mode of transport for many invasive species, including diseases and agricultural pests. Most species are brought to their new homes unintentionally, which constitutes a market failure rooted in international trade. Unless it is practical to drive invasion risk to zero, the external costs may justify a tariff. In this paper, we analyze the political process

Michael Margolis; Jason F. Shogren; Carolyn Fischer

2005-01-01

345

Less invasive autopsy: an evidenced based approach  

Microsoft Academic Search

Despite the initial promises, less invasive autopsy by postmortem MRI has not gained widespread acceptance and is not yet used as a clinical tool. Current evidence on postmortem MRI is primarily limited to examination of fetal brain malformations. Large prospective studies funded by the UK Department of Health evaluating accuracy of postmortem MRI are now nearing completion. Less invasive autopsies

Sudhin Thayyil

2011-01-01

346

Conservation Implications of Invasion by Plant Hybridization  

Microsoft Academic Search

The increasing number of invasive exotic plant species in many regions and the continuing alteration of natural ecosystems by humans promote hybridization between previously allopatric species; among both native as well as between native and introduced species. We review the ecological factors and mechanisms that promote such hybridization events and their negative consequences on biological diversity. Plant invasions through hybridization

Montserrat Vilà; Ewald Weber; Carla M. D Antonio

2000-01-01

347

Avian Seed Dispersal of an Invasive Shrub  

Microsoft Academic Search

The incorporation of an animal-dispersed exotic plant species into the diet of native frugivores can be an important step to that species becoming invasive. We investigated bird dispersal of Lonicera maackii, an Asian shrub invasive in eastern North America. We (i) determined which species of birds disperse viable L. maackii seeds, (ii) tested the effect of gut passage on L.

Anne M. Bartuszevige; David L. Gorchov

2006-01-01

348

The Invasive Plant Species Education Guide  

ERIC Educational Resources Information Center

|To help high school students gain a solid understanding of invasive plant species, university faculty and students from the University of Wisconsin-Stout (UW-Stout) and a local high school teacher worked together to develop the Invasive Plant Species (IPS) Education Guide. The IPS Education Guide includes nine lessons that give students an…

Mason, Kevin; James, Krista; Carlson, Kitrina; D'Angelo, Jean

2010-01-01

349

Plant invasions – the role of mutualisms  

Microsoft Academic Search

Many introduced plant species rely on mutualisms in their new habitats to overcome barriers to establishment and to become naturalized and, in some cases, invasive. Mutualisms involving animal- mediated pollination and seed dispersal, and symbioses between plant roots and microbiota often facilitate invasions. The spread of many alien plants, particularly woody ones, depends on pollinator mutualisms. Most alien plants are

DAVID M. RICHARDSON; NICKY ALLSOPP; CARLA M. D'ANTONIO; SUZANNE J. MILTON; MARCEL REJMÁNEK

2000-01-01

350

Invasion of Dentinal Tubules by Oral Bacteria  

Microsoft Academic Search

Bacterial invasion of dentinal tubules commonly occurs when dentin is exposed following a breach in the integrity of the overlying enamel or cementum. Bacterial products diffuse through the dentinal tubule toward the pulp and evoke inflammatory changes in the pulpo-dentin complex. These may eliminate the bacterial insult and block the route of infection. Unchecked, invasion results in pulpitis and pulp

R. M. Love; H. F. Jenkinson

2002-01-01

351

Indirect effects of parasites in invasions  

Technology Transfer Automated Retrieval System (TEKTRAN)

Introduced species disrupt native communities and biodiversity worldwide. Parasitic infections (and at times, their absence) are thought to be a key component in the success and impact of biological invasions by plants and animals. They can facilitate or limit invasions, and positively or negatively...

352

Immobilizing nitrogen to control plant invasion  

Technology Transfer Automated Retrieval System (TEKTRAN)

1. Increased soil nitrogen (N) availability may often facilitate plant invasions. Therefore, lowering N availability might be expected to reduce those invasions and favor native species. Numerous studies have examined effects of low N availability on specific invaders, but a synthesis of these stu...

353

Book review: Encyclopedia of biological invasions  

Treesearch

... introductions and consequent biotic invasions and homogenization are major components of ... concern and various levels of actions and reactions around the world. ... For basic research, invasion biology offers fascinating and sometimes unique ... This article was written and prepared by U.S. Government employees on ...

354

Predator control promotes invasive dominated ecological states.  

PubMed

Invasive species are regarded as one of the top five drivers of the global extinction crisis. In response, extreme measures have been applied in an attempt to control or eradicate invasives, with little success overall. We tested the idea that state shifts to invasive dominance are symptomatic of losses in ecosystem resilience, due to the suppression of apex predators. This concept was investigated in Australia where the high rate of mammalian extinctions is largely attributed to the destructive influence of invasive species. Intensive pest control is widely applied across the continent, simultaneously eliminating Australia's apex predator, the dingo (Canis lupus dingo). We show that predator management accounts for shifts between two main ecosystem states. Lethal control fractures dingo social structure and leads to bottom-up driven increases in invasive mesopredators and herbivores. Where control is relaxed, dingoes re-establish top-down regulation of ecosystems, allowing for the recovery of biodiversity and productivity. PMID:20545732

Wallach, Arian D; Johnson, Christopher N; Ritchie, Euan G; O'Neill, Adam J

2010-06-10

355

[Non-invasive mechanical ventilation in COPD].  

PubMed

Non-invasive mechanical ventilation is the preferred method for the treatment of acute respiratory failure in patients with chronic obstructive pulmonary disease (COPD). Primary contraindications and stopping criteria must be regarded to avoid delaying endotracheal intubation. The primary interface is usually a nasal-oral mask. Cautious sedation can facilitate non-invasive ventilation in some patients. Under certain circumstances non-invasive ventilation may enable successful extubation in COPD patients with prolonged weaning. COPD patients can also benefit from preventive non-invasive ventilation in order to avoid re-intubation after a planned extubation. Domiciliary nocturnal non-invasive ventilation is an option for some patients with COPD in chronic hypercapnic respiratory failure. This treatment should be established in a specialised unit. PMID:22415450

Funk, G-C

2012-03-15

356

78 FR 14351 - Invasive Species Advisory Committee; Meeting Cancellation  

Federal Register 2010, 2011, 2012, 2013

...INTERIOR Office of the Secretary Invasive Species Advisory Committee; Meeting...SUMMARY: The meeting of the Invasive Species Advisory Committee (ISAC...is comprised of 31 nonfederal invasive species experts and stakeholders...

2013-03-05

357

Linking biotic homogenization to habitat type, invasiveness and ...  

Treesearch

Methods We assembled species lists of native and alien vascular plants for ... to habitat (wetland versus upland), invasiveness (invasive versus non-invasive), ... of the mean beta diversity of alien species for each set of localities examined in ...

358

A human breast cell model of pre-invasive to invasive transition  

SciTech Connect

A crucial step in human breast cancer progression is the acquisition of invasiveness. There is a distinct lack of human cell culture models to study the transition from pre-invasive to invasive phenotype as it may occur 'spontaneously' in vivo. To delineate molecular alterations important for this transition, we isolated human breast epithelial cell lines that showed partial loss of tissue polarity in three-dimensional reconstituted-basement membrane cultures. These cells remained non-invasive; however, unlike their non-malignant counterparts, they exhibited a high propensity to acquire invasiveness through basement membrane in culture. The genomic aberrations and gene expression profiles of the cells in this model showed a high degree of similarity to primary breast tumor profiles. The xenograft tumors formed by the cell lines in three different microenvironments in nude mice displayed metaplastic phenotypes, including squamous and basal characteristics, with invasive cells exhibiting features of higher grade tumors. To find functionally significant changes in transition from pre-invasive to invasive phenotype, we performed attribute profile clustering analysis on the list of genes differentially expressed between pre-invasive and invasive cells. We found integral membrane proteins, transcription factors, kinases, transport molecules, and chemokines to be highly represented. In addition, expression of matrix metalloproteinases MMP-9,-13,-15,-17 was up regulated in the invasive cells. Using siRNA based approaches, we found these MMPs to be required for the invasive phenotype. This model provides a new tool for dissection of mechanisms by which pre-invasive breast cells could acquire invasiveness in a metaplastic context.

Bissell, Mina J; Rizki, Aylin; Weaver, Valerie M.; Lee, Sun-Young; Rozenberg, Gabriela I.; Chin, Koei; Myers, Connie A.; Bascom, Jamie L.; Mott, Joni D.; Semeiks, Jeremy R.; Grate, Leslie R.; Mian, I. Saira; Borowsky, Alexander D.; Jensen, Roy A.; Idowu, Michael O.; Chen, Fanqing; Chen, David J.; Petersen, Ole W.; Gray, Joe W.; Bissell, Mina J.

2008-03-10

359

Assessing Biofuel Crop Invasiveness: A Case Study  

PubMed Central

Background There is widespread interest in biofuel crops as a solution to the world's energy needs, particularly in light of concerns over greenhouse-gas emissions. Despite reservations about their adverse environmental impacts, no attempt has been made to quantify actual, relative or potential invasiveness of terrestrial biofuel crops at an appropriate regional or international scale, and their planting continues to be largely unregulated. Methodology/Principal Findings Using a widely accepted weed risk assessment system, we analyzed a comprehensive list of regionally suitable biofuel crops to show that seventy percent have a high risk of becoming invasive versus one-quarter of non-biofuel plant species and are two to four times more likely to establish wild populations locally or be invasive in Hawaii or in other locations with a similar climate. Conclusions/Significance Because of climatic and ecological similarities, predictions of biofuel crop invasiveness in Hawaii are applicable to other vulnerable island and subtropical ecosystems worldwide. We demonstrate the utility of an accessible and scientifically proven risk assessment protocol that allows users to predict if introduced species will become invasive in their region of interest. Other evidence supports the contention that propagule pressure created by extensive plantings will exacerbate invasions, a scenario expected with large-scale biofuel crop cultivation. Proactive measures, such as risk assessments, should be employed to predict invasion risks, which could then be mitigated via implementation of appropriate planting policies and adoption of the “polluter-pays” principle.

Buddenhagen, Christopher Evan; Chimera, Charles; Clifford, Patti

2009-01-01

360

Cholecystitis in Guinea Pigs Following Opium.  

National Technical Information Service (NTIS)

Acute cholecystitis was produced in normal guinea pigs given intraperitoneal injections of 1.0 ml tincture of opium. Repeated injections of opium caused edema of the lamina propria and severe muscular hypertrophy. Occasional Rokitansky-Aschoff sinuses wer...

H. B. Goldstein

1966-01-01

361

National Institute of Invasive Species Science  

NSDL National Science Digital Library

The National Institute of Invasive Species Science (NIISS) supports a database with extensive information on invasive species around the United States. The data on individual species can be searched by scientific name, common name or National Resource Convervation Service (NRCS) Code. There is also a geographic search that allows users to locate invasives by state, county, National Park Service unit, Fish and Wildlife Service refuge, or by state parks. A query/search/browse function permits browsing by organization, location, species, project, or map. The front page features links to news articles and information on new products.

362

San Francisco Estuary: Invasive Spartina Project  

NSDL National Science Digital Library

The Invasive Spartina Project was developed by the California State Coastal Conservancy to determine the extent and address the problem of invasive Spartina in the San Francisco Estuary. This Web site describes the efforts of the Invasive Spartina Project and the risk that Spartina poses. A variety of maps and photos are used to describe the results of the 2000-2001 survey of Spartina populations within the estuary. A host of other documents regarding Spartina and this project are also available in Adobe Acrobat (.pdf) format.

2002-01-01

363

The United States National Arboretum: Invasive Plants  

NSDL National Science Digital Library

The US National Arboretum offers this straightforward guide to invasive plants that gardeners and property owners in general should watch for. The Web site begins with an explanation of what the term "invasive" really means, followed by photos and descriptions of species to avoid planting altogether (such as purple loosestrife), and those that are less problematic if managed wisely (like English ivy). The site also describes the origin and current distribution of some of the most commonly encountered invasive plants, and provides Web links for further information.

2002-01-01

364

Cutaneous Model of Invasive Aspergillosis?  

PubMed Central

Cutaneous models have proven useful in studies of the pathogenesis and treatment of Gram-positive bacterial infections. Because cutaneous invasive aspergillosis (IA) occurs in the clinical setting, we sought to develop a nonlethal murine cutaneous model of IA. We induced cutaneous IA in cyclophosphamide-treated nude BALB/c mice by subcutaneous injection of Aspergillus fumigatus conidia. Skin lesion areas correlated well with tissue fungal burdens, allowing dynamic visual monitoring of cutaneous infections. The cutaneous model accurately reflected alterations in A. fumigatus pathogenicity resulting from deletions of recognized virulence genes (pabaA, sidA, and pksP). Moreover, analysis of the roles of conidial and mycelial catalases revealed that the former is required for the initiation of cutaneous aspergillosis, whereas the latter contributes to its propagation. Finally, posaconazole treatment reduced skin lesion areas relative to those of untreated and fluconazole-treated controls. This novel cutaneous model system should be applicable to comparative studies of the pathogenesis, treatment, and tissue specificity of IA.

Ben-Ami, Ronen; Lewis, Russell E.; Leventakos, Konstantinos; Latge, Jean-Paul; Kontoyiannis, Dimitrios P.

2010-01-01

365

Distribution of immunoglobulin producing cells is different in normal human appendix and colon mucosa  

Microsoft Academic Search

The densities of IgG-, IgA-, IgM- and IgD-producing immunocytes were determined by paired immunofluorescence staining and morphometric analysis in the lamina propria of normal appendix specimens. Normal colon specimens were used as reference material, mostly paired from individual subjects. The density (median of cells\\/mm2 lamina propria area) of IgA immunocytes tended to be slightly higher in the appendix than in

K Bjerke; P Brandtzaeg; T O Rognum

1986-01-01

366

Recent Trends in Minimally Invasive Cardiac Surgery  

Microsoft Academic Search

Evolving technologies have resulted in an increase in minimally invasive cardiac surgery. Currently, robotic systems allow surgeons to perform a variety of procedures through small incisions. This changing paradigm is reviewed.

Alan P. Kypson

2007-01-01

367

EBIPM 2013 planner for preventing weed invasion  

Technology Transfer Automated Retrieval System (TEKTRAN)

Using a calendar format, this publication is designed for land managers to make management decisions for preventing weed invasions in a timely manner. For each month there are recommendations for wee prevention management actions....

368

Clearance of invasive melanoma with topical imiquimod.  

PubMed

A 93-year-old woman presented with biopsy-proven invasive melanoma of 2.75 mm depth, arising from a melanoma in situ. Standard treatment of this depth would be an extensive and mutilating excision, which presented a therapeutic dilemma. Imiquimod has the ability to clear melanoma in situ, but its effect on invasive melanoma is unknown. After a thorough discussion with the patient, we decided to attempt to treat the melanoma in situ with topical imiquimod and then excise the smaller invasive component. Following 5 weeks of topical imiquimod therapy, the area where the nodular melanoma had previously been was excised. Histological examination of the excisional specimen revealed no residual melanoma detected. In this case, it appears that 5 weeks of topical imiquimod therapy completely cleared an invasive melanoma of 2.75 mm depth, as well as clearing the component of melanoma in situ. The patient was followed for 14 months with no evidence of recurrence. PMID:23377337

Moon, Summer D; Spencer, James M

2013-01-01

369

Aquatic plant community invasibility and scale-dependent patterns in native and invasive species richness.  

PubMed

Invasive species richness often is negatively correlated with native species richness at the small spatial scale of sampling plots, but positively correlated in larger areas. The pattern at small scales has been interpreted as evidence that native plants can competitively exclude invasive species. Large-scale patterns have been understood to result from environmental heterogeneity, among other causes. We investigated species richness patterns among submerged and floating-leaved aquatic plants (87 native species and eight invasives) in 103 temperate lakes in Connecticut (northeastern USA) and found neither a consistently negative relationship at small (3-m2) scales, nor a positive relationship at large scales. Native species richness at sampling locations was uncorrelated with invasive species richness in 37 of the 60 lakes where invasive plants occurred; richness was negatively correlated in 16 lakes and positively correlated in seven. No correlation between native and invasive species richness was found at larger spatial scales (whole lakes and counties). Increases in richness with area were uncorrelated with abiotic heterogeneity. Logistic regression showed that the probability of occurrence of five invasive species increased in sampling locations (3 m2, n = 2980 samples) where native plants occurred, indicating that native plant species richness provided no resistance against invasion. However, the probability of three invasive species' occurrence declined as native plant density increased, indicating that density, if not species richness, provided some resistance with these species. Density had no effect on occurrence of three other invasive species. Based on these results, native species may resist invasion at small spatial scales only in communities where density is high (i.e., in communities where competition among individuals contributes to community structure). Most hydrophyte communities, however, appear to be maintained in a nonequilibrial condition by stress and/or disturbance. Therefore, most aquatic plant communities in temperate lakes are likely to be vulnerable to invasion. PMID:18229847

Capers, Robert S; Selsky, Roslyn; Bugbee, Gregory J; White, Jason C

2007-12-01

370

Is there an equivalence of non-invasive to invasive referenciation in computer-aided surgery?  

PubMed

Various navigation systems with non-invasive patient referenciation and registration methods have been developed in times of minimal-invasive and computer-aided surgery. However, hard data proving the equivalence of different referenciation systems are missing. The present study investigated invasive and non-invasive referenciation systems with regard to overall navigation accuracy as well as navigation accuracy at specific anatomic locations. Four skull models were individually fabricated with a 3D printer based on patient's CT data sets and fitted with an individual customized silicone skin. 26 titanium screws on defined anatomic locations served as target fiducials. Two non-invasive referenciation systems (headband and headset) were compared with the invasive skull fixed reference array. Registration was done with laser surface scan. The mean accuracy was calculated and the target registration error for eight anatomical locations was measured. Mean accuracy was 1.3 ± 0.12 mm for the skull fixed reference array, 1.44 ± 0.24 mm for the headset and 1.46 ± 0.15 mm for the headband referenciation (non-significant). Navigation accuracy of the invasive referenciation system was significantly superior to the accuracy of both non-invasive systems on the ethmoid sinus with respect to the selected anatomic locations. In the midface headband referenciation was statistically significantly worse than the invasive system. Invasive and non-invasive referenciation systems seem to be on par in terms of overall navigation accuracy, but not regarding specific anatomic locations. Therefore, invasive referenciation systems should be preferred in high precision surgery. PMID:22562399

Grauvogel, Tanja D; Grauvogel, Juergen; Arndt, Susan; Berlis, Ansgar; Maier, Wolfgang

2012-05-05

371

Invasive aphids attack native Hawaiian plants  

Microsoft Academic Search

Invasive species have had devastating impacts on the fauna and flora of the Hawaiian Islands. While the negative effects of\\u000a some invasive species are obvious, other species are less visible, though no less important. Aphids (Homoptera: Aphididae)\\u000a are not native to Hawai’i but have thoroughly invaded the Island chain, largely as a result of anthropogenic influences. As\\u000a aphids cause both

Russell H. Messing; Michelle N. Tremblay; Edward B. Mondor; Robert G. Foottit; Keith S. Pike

2007-01-01

372

Augmented Reality in Minimally Invasive Surgery  

Microsoft Academic Search

In the last 15 years Minimally Invasive Surgery, with techniques such as laparoscopy or endoscopy, has become very important\\u000a and research in this field is increasing since these techniques provide the surgeons with less invasive means of reaching\\u000a the patient’s internal anatomy and allow for entire procedures to be performed with only minimal trauma to the patient. The\\u000a advantages of

Lucio Tommaso De Paolis; Giovanni Aloisio

373

Genetics of Invasive Species in New Zealand  

Microsoft Academic Search

Genetic effects following the colonization and invasion of New Zealand have been studied in relatively few cases for a variety\\u000a of reasons. The outcomes of these studies have shown that there are ranges of genetic effects that do occur after colonization,\\u000a although it is often difficult to attribute genetics as a factor in the success or failure of invasive species.

D. Gleeson; H. Harman; T. Armstrong

374

Does consumer injury modify invasion impact?  

Microsoft Academic Search

Predicting the impacts of an invasive species solely by its abundance is common, yet it ignores other potentially important\\u000a moderating factors. One such factor is injury. Severe injury can lead to mortality, which can directly reduce the abundance\\u000a of the invader. However, more moderate, sublethal injury can also temper the impact of invasive species. Therefore, to predict\\u000a impacts, it may

David G. DelaneyBlaine; Blaine D. Griffen; Brian Leung

375

Invasive pneumococcal disease in Australia, 2002  

Microsoft Academic Search

There were 2,271 cases of invasive pneumococcal disease (IPD) notifi ed to the National Notifi able Diseases Surveillance System in Australia in 2002; a rate of 11.5 cases per 100,000 population. The notifi cation rate varied between states and territories and by geographical region with the highest rates in the north of the country. Invasive pneumococcal disease was reported most

Paul Roche; Vicki Krause; Ross Andrews; Louise Carter; David Coleman; Heather Cook; Megan Counahan; Ros Holland; Riemke Kampen; Mitchell Brown; Lyn Gilbert; Geoff Hogg; Denise Murphy

376

The evolution of invasiveness in garden ants.  

PubMed

It is unclear why some species become successful invaders whilst others fail, and whether invasive success depends on pre-adaptations already present in the native range or on characters evolving de-novo after introduction. Ants are among the worst invasive pests, with Lasius neglectus and its rapid spread through Europe and Asia as the most recent example of a pest ant that may become a global problem. Here, we present the first integrated study on behavior, morphology, population genetics, chemical recognition and parasite load of L. neglectus and its non-invasive sister species L. turcicus. We find that L. neglectus expresses the same supercolonial syndrome as other invasive ants, a social system that is characterized by mating without dispersal and large networks of cooperating nests rather than smaller mutually hostile colonies. We conclude that the invasive success of L. neglectus relies on a combination of parasite-release following introduction and pre-adaptations in mating system, body-size, queen number and recognition efficiency that evolved long before introduction. Our results challenge the notion that supercolonial organization is an inevitable consequence of low genetic variation for chemical recognition cues in small invasive founder populations. We infer that low variation and limited volatility in cuticular hydrocarbon profiles already existed in the native range in combination with low dispersal and a highly viscous population structure. Human transport to relatively disturbed urban areas thus became the decisive factor to induce parasite release, a well established general promoter of invasiveness in non-social animals and plants, but understudied in invasive social insects. PMID:19050762

Cremer, Sylvia; Ugelvig, Line V; Drijfhout, Falko P; Schlick-Steiner, Birgit C; Steiner, Florian M; Seifert, Bernhard; Hughes, David P; Schulz, Andreas; Petersen, Klaus S; Konrad, Heino; Stauffer, Christian; Kiran, Kadri; Espadaler, Xavier; d'Ettorre, Patrizia; Aktaç, Nihat; Eilenberg, Jørgen; Jones, Graeme R; Nash, David R; Pedersen, Jes S; Boomsma, Jacobus J

2008-12-03

377

Metalloproteinases in Human Invasive Breast Carcinomas  

Microsoft Academic Search

Activation of the zymogen of matrix metalloprotelnase 2 (proMMP-2, progelatinase A) possibly is one ofthe key steps In Invasion and metastasis of varioushumancarcinomas. Threedifferentmembrane-type MMPS (MT-MMPs), MT1., MT2-, and MT3-MMPSare thought to be activators of proMMP-2 Inthetissues.MT4.MMP Isstructurally differentfromthe other three enzymes, sad Its function as proMMP-2 activator is uncertain. Inthepresentstudyof humanInvasive breastcarcinomas, weexamined a correlation between the expression of

Hirohisa Ueno; Hiroyuki Nakamura; Masaki Inoue; Kazushi Imai; Masakuni Noguchi; Hiroshi Sato; Motoharu Seiki; Yasunori Okada

378

Non-Invasive Monitoring of Diabetes  

Microsoft Academic Search

Non-invasive (NI) monitoring of glucose has attracted tremendous attention in the past two decades, mainly because diabetes\\u000a is expected to be a major epidemic due to the increased overall obesity of the population. Non-Invasive monitoring of glucose\\u000a decreases the pain associated with skin lancing used to sample blood for home glucose monitors. Reduction in pain can encourage\\u000a more frequent testing

Omar S. Khalil

379

[Minimally invasive percutaneous nephrolitholapaxy (MIP)].  

PubMed

Minimally invasive percutaneous nephrolithopaxy (MIP) was developed to combine the excellent stone-free rates of the conventional percutaneous nephrolithopaxy (PCNL) technique with the low morbidity of the miniaturized PCNL (Mini-Perc) and, at the same time, achieve a high level of patient comfort. The procedure is characterized not only by the diameter of the miniaturized 18-Fr Amplatz sheath that was adopted from the Mini-Perc but also by the following features: ultrasound-guided puncture of the kidney; single-step dilatation of the access tract; ballistic lithotripsy; a low-pressure irrigation system together with stone retraction by irrigation with a specially designed nephroscope sheath, for the so-called vacuum cleaner effect; and a sealed and tubeless access tract with primary closure of the channel independent of hemorrhage and without a second-look procedure.The results of the first 57 patients demonstrate primary stone-free rates of 92.9% with operating times averaging 62 (25-123) min. Severe complications, such as sepsis or bleeding requiring blood transfusion, did not occur. The high and predictable stone-free rate and a low morbidity comparable to that of ureteroscopy and extracorporeal shock-wave lithotripsy make MIP an attractive option for patients and urologists. The "vacuum cleaner effect" with quick removal of stone fragments reduces operating time and prevents new stone formation by avoiding residual fragments. The direct and primary closure of the access tract increases patient comfort and is justified by the reintervention rate of less than 8% in the presented cohort.The lack of a need for second-look nephroscopies, the vacuum cleaner effect, improved patient comfort without nephrostomy tubes, as well as surgery times comparable to that of traditional PCNL demonstrate a consequent evolution of the Mini-Perc. MIP therefore represents a promising and future-oriented module in modern stone therapy. PMID:18709351

Nagele, U; Schilling, D; Anastasiadis, A G; Walcher, U; Sievert, K D; Merseburger, A S; Kuczyk, M; Stenzl, A

2008-09-01

380

In Vivo Assay for Tumor Cell Invasion  

PubMed Central

Summary We describe an in vivo invasion assay that enables the collection of invasive cells from the primary tumor. In addition to determination of the endogenous, unstimulated invasive properties of cells in vivo, the assay can take advantage of the chemotactic properties of cancer cells. Microneedles are filled with a mixture of extracellular matrix components such as Matrigel with or without a chemoattractant such as EGF, and then introduced into the primary tumor of a rat or mouse that is generated either by orthotopic injection of carcinoma cell lines or by a transgene such as polyoma Middle T. Over the course of 4 h the invasive cell population enters the needles while the animal is kept under anesthesia. At the end of the collection time, the invasive cells are extruded from the microneedles and can be analyzed in terms of the number and type of cells that invade in response to defined stimuli. By including pharmacological inhibitors in the needle, signaling pathways contributing to in vivo invasion can also be identified. This assay leads to a better understanding of the cell types and signaling involved in the tumor microenvironment, and has the potential to be applied to a variety of in vivo models.

Hernandez, Lorena; Smirnova, Tatiana; Wyckoff, Jeffrey; Condeelis, John; Segall, Jeffrey E.

2010-01-01

381

Minimally invasive surgery in gynecologic oncology.  

PubMed

Minimally invasive surgery has been utilized in the field of obstetrics and gynecology as far back as the 1940s when culdoscopy was first introduced as a visualization tool. Gynecologists then began to employ minimally invasive surgery for adhesiolysis and obtaining biopsies but then expanded its use to include procedures such as tubal sterilization (Clyman (1963), L. E. Smale and M. L. Smale (1973), Thompson and Wheeless (1971), Peterson and Behrman (1971)). With advances in instrumentation, the first laparoscopic hysterectomy was successfully performed in 1989 by Reich et al. At the same time, minimally invasive surgery in gynecologic oncology was being developed alongside its benign counterpart. In the 1975s, Rosenoff et al. reported using peritoneoscopy for pretreatment evaluation in ovarian cancer, and Spinelli et al. reported on using laparoscopy for the staging of ovarian cancer. In 1993, Nichols used operative laparoscopy to perform pelvic lymphadenectomy in cervical cancer patients. The initial goals of minimally invasive surgery, not dissimilar to those of modern medicine, were to decrease the morbidity and mortality associated with surgery and therefore improve patient outcomes and patient satisfaction. This review will summarize the history and use of minimally invasive surgery in gynecologic oncology and also highlight new minimally invasive surgical approaches currently in development. PMID:23997959

Mori, Kristina M; Neubauer, Nikki L

2013-08-12

382

Understanding the genetic basis of invasiveness.  

PubMed

Invasive species provide excellent study systems to evaluate the ecological and evolutionary processes that contribute to the colonization of novel environments. While the ecological processes that contribute to the successful establishment of invasive plants have been studied in detail, investigation of the evolutionary processes involved in successful invasions has only recently received attention. In particular, studies investigating the genomic and gene expression differences between native and introduced populations of invasive species are just beginning and are required if we are to understand how plants become invasive. In the current issue of Molecular Ecology, Hodgins et al. (2013) tackle this unresolved question, by examining gene expression differences between native and introduced populations of annual ragweed, Ambrosia artemisiifolia. The study identifies a number of potential candidate genes based on gene expression differences that may be responsible for the success of annual ragweed in its introduced range. Furthermore, genes involved in stress response are over-represented in the differentially expressed gene set. Future experiments could use functional studies to test whether changes in gene expression at these candidate genes do in fact underlie changes in growth characteristics and reproductive output observed in this and other invasive species. PMID:23738371

Prentis, Peter J; Pavasovic, Ana

2013-05-01

383

Immobilizing nitrogen to control plant invasion.  

PubMed

Increased soil N availability may often facilitate plant invasions. Therefore, lowering N availability might reduce these invasions and favor desired species. Here, we review the potential efficacy of several commonly proposed management approaches for lowering N availability to control invasion, including soil C addition, burning, grazing, topsoil removal, and biomass removal, as well as a less frequently proposed management approach for lowering N availability, establishment of plant species adapted to low N availability. We conclude that many of these approaches may be promising for lowering N availability by stimulating N immobilization, even though most are generally ineffective for removing N from ecosystems (excepting topsoil removal). C addition and topsoil removal are the most reliable approaches for lowering N availability, and often favor desired species over invasive species, but are too expensive or destructive, respectively, for most management applications. Less intensive approaches, such as establishing low-N plant species, burning, grazing and biomass removal, are less expensive than C addition and may lower N availability if they favor plant species that are adapted to low N availability, produce high C:N tissue, and thus stimulate N immobilization. Regardless of the method used, lowering N availability sufficiently to reduce invasion will be difficult, particularly in sites with high atmospheric N deposition or agricultural runoff. Therefore, where feasible, the disturbances that result in high N availability should be limited in order to reduce invasions by nitrophilic weeds. PMID:20387033

Perry, Laura G; Blumenthal, Dana M; Monaco, Thomas A; Paschke, Mark W; Redente, Edward F

2010-02-21

384

Invasion Dynamics of Cytisus scoparius: A Matrix Model Approach  

Microsoft Academic Search

It is at the level of population dynamics that an invasion either fails or succeeds. By elucidating patterns of variation in population growth rates or demographic rates, it is possible to forge a connection between quantitative field data and theoretical ideas about invasiveness, invasibility, and rates of spread. Demographic models also provide a tool to guide control strategies for invasive

Ingrid M. Parker

2000-01-01

385

Animal behavior: an essential component of invasion biology  

Microsoft Academic Search

A major challenge of invasion biology lies in the development of a predictive understanding of invasion processes. Attempts to identify the proximate causes of invasion success or to predict rates of spread seldom emphasize behavioral characteristics. Recent experimental work, however, illustrates that insight into the proximate causes of animal invasions often hinges on a careful assessment of behavioral mechanisms. For

David A Holway; Andrew V Suarez

1999-01-01

386

Plant Polyphenolics as Anti-Invasive Cancer Agents  

Microsoft Academic Search

Because invasion is, either directly or via metastasis formation, the main cause of death in cancer patients, development of ef- ficient anti-invasive agents is an important research challenge. We have established a screening program for potentially anti-invasive compounds. The assay is based on organotypic confronting cultures between human invasive cancer cells and a fragment of normal tissue in three dimensions.

V. S. Parmar; M. E. Bracke; B. W. A. Vanhoecke; L. Derycke; S. Bolca; S. Possemiers; A. Heyerick; C. V. Stevens; D. D. Keukeleire; H. T. Depypere; W. Verstraete; C. A. Williams; S. T. McKenna; S. Tomar; D. Sharma; A. K. Prasad; A. L. DePass

2008-01-01

387

Invasive species information networks: collaboration at multiple scales for prevention, early detection, and rapid response to invasive alien species  

Microsoft Academic Search

Accurate analysis of present distributions and effective modeling of future distributions of invasive alien species (IAS) are both highly dependent on the availability and accessibility of occurrence data and natural history information about the species. Invasive alien species monitoring and detection networks (such as the Invasive Plant Atlas of New England and the Invasive Plant Atlas of the MidSouth) generate

Annie Simpson; Catherine Jarnevich; John Madsen; Randy Westbrooks; Christine Fournier; Les Mehrhoff; Michael Browne; Jim Graham; Elizabeth Sellers

2009-01-01

388

Global phylogenetics of Diuraphis noxia (Hemiptera: Aphididae), an invasive aphid species: Evidence for multiple invasions into North America  

Technology Transfer Automated Retrieval System (TEKTRAN)

Critical to the study of an invasive species is understanding the number and origin of invasions that have occurred, as well as the rate or potential of post-invasion adaptation and geographic range expansion. One virulent, invasive insect species that has caused much damage in the United States is...

389

Invasive cordgrass modifies wetland trophic function.  

PubMed

Vascular plants strongly control belowground environments in most ecosystems. Invasion by vascular plants in coastal wetlands, and by cordgrasses (Spartina spp.) in particular, are increasing in incidence globally, with dramatic ecosystem-level consequences. We examined the trophic consequences of invasion by a Spartina hybrid (S. alterniflora x S. foliosa) in San Francisco Bay (USA) by documenting differences in biomass and trophic structure of benthic communities between sediments invaded by Spartina and uninvaded sediments. We found the invaded system shifted from an algae-based to a detritus-based food web. We then tested for a relationship between diet and tolerance to invasion, hypothesizing that species that consume Spartina detritus are more likely to inhabit invaded sediments than those that consume surface algae. Infaunal diets were initially examined with natural abundance stable isotope analyses and application of mixing models, but these yielded an ambiguous picture of food sources. Therefore, we conducted isotopic enrichment experiments by providing 15N-labeled Spartina detritus both on and below the sediment surface in areas that either contained Spartina or were unvegetated. Capitellid and nereid polychaetes, and oligochaetes, groups shown to persist following Spartina invasion of San Francisco Bay tidal flats, took up 15N from labeled native and invasive Spartina detritus. In contrast, we found that amphipods, bivalves, and other taxa less tolerant to invasion consumed primarily surficial algae, based on 13C enrichment experiments. Habitat (Spartina vs. unvegetated patches) and location of detritus (on or within sediments) did not affect 15N uptake from detritus. Our investigations support a "trophic shift" model for ecosystem response to wetland plant invasion and preview loss of key trophic support for fishes and migratory birds by shifting dominance to species not widely consumed by species at higher trophic levels. PMID:16637367

Levin, Lisa A; Neira, Carlos; Grosholz, Edwin D

2006-02-01

390

B-1-cell subpopulations contribute differently to gut immunity.  

PubMed

In mice, B-1 (B1a/B1b) cells are mainly located in the peritoneal cavity. B-1 cells are well known for their role in the early stages of Ab-mediated immune responses against pathogenic invasion as well as for the production of natural IgM antibodies. Although such B cells have been claimed to give rise to intestinal plasma cells producing IgA, a clear role of B-1 cells in IgA production in the gut-associated tissues is still not defined. Here, we employed the transgenic L2 mouse model characterized by the lack of B-2 cells and presence of B-1 cells as major B-cell subpopulation. The oligoclonality of the Ab repertoire in this mouse allowed us to take typical B1a cell VH sequences as indicators of the presence of IgM-producing B-1a cells in Peyer's patches as well as in lamina propria. However, amongst the IgAVH sequences recovered from the same tissues, none of the sequences showed B1a-cell specificity. Interestingly, all IgAVH sequences derived from the lamina propria of L2 mice displayed extensive numbers of nucleotide exchanges, indicating somatic hypermutation, and affinity maturation. This suggests that the contribution of natural unmutated IgA by B-1a cells to intestinal immunity is negligible. PMID:23677546

Roy, Bishnudeo; Agarwal, Shiwani; Brennecke, Anne-Margarete; Krey, Martina; Pabst, Oliver; Düber, Sandra; Weiss, Siegfried

2013-06-12

391

General guidelines for invasive plant management based on comparative demography of invasive and native plant populations  

Microsoft Academic Search

Summary 1. General guidelines for invasive plant management are currently lacking. Population declines may be achieved by focusing control on demographic processes (survival, growth, fecundity) with the greatest impact on population growth rate. However, we often have little demographic information on populations in the early stages of an invasion when control can be most effective. Here we determine whether synthesis

Satu Ramula; Tiffany M. Knight; Jean H. Burns; Yvonne M. Buckley

2008-01-01

392

The Invasive Species Forecasting System: A Space-Based Decision Support Infrastructure for Managing Biological Invasions  

NASA Astrophysics Data System (ADS)

The spread of invasive species is one of the most daunting environmental, economic, and human-health problems facing the United States and the World today. It is one of several grand challenge environmental problems being addressed by NASA's Science Mission Directorate through a national application partnership with the US Geological Survey. NASA and USGS are working together to develop a National Invasive Species Forecasting System (ISFS) for the management and control of invasive species on Department of Interior and adjacent lands. As part of this effort, we are using NASA's EOS Clearing House (ECHO) framework to create an Invasive Species Data Service (ISDS). The ISDS will be a networked service that integrates a suite of NASA remote sensing data providers with the ecological field data resources of the National Biological Information Infrastructure (NBII). Aggregated ISDS data will feed directly into ISFS analysis routines to produce landscape-scale predictive maps of species distributions. ISDS and the ECHO framework thus provide an efficient interface between existing NASA data systems and decision support systems that are the province of federal agencies and other national organizations. The effort significantly broadens the use of NASA data in managing the Nation's invasive species threat. In this talk, we will describe the NASA/USGS invasive species partnership, provide an overview of the Invasive Species Forecasting System, and show how we are using ECHO technologies as the middle-ware framework for a comprehensive Invasive Species Data Service.

Most, N. N.; Kendig, D.; Wichman, K.; Pollack, N.; Ilagan, A.; Morisette, J. T.; Pedelty, J. A.; Tilmes, C.; Smith, J. A.; Pfister, R.; Schnase, J. L.; Stohgren, T. J.; Crosier, C.; Graham, J.; Newman, G.; Kalkhan, M. A.; Reich, R.

2004-12-01

393

Roles for herpes simplex virus type 1 U{sub L}34 and U{sub S}3 proteins in disrupting the nuclear lamina during herpes simplex virus type 1 egress  

SciTech Connect

Cells infected with wild type HSV-1 showed significant lamin A/C and lamin B rearrangement, while U{sub L}34-null virus-infected cells exhibited few changes in lamin localization, indicating that U{sub L}34 is necessary for lamin disruption. During HSV infection, U{sub S}3 limited the development of disruptions in the lamina, since cells infected with a U{sub S}3-null virus developed large perforations in the lamin layer. U{sub S}3 regulation of lamin disruption does not correlate with the induction of apoptosis. Expression of either U{sub L}34 or U{sub S}3 proteins alone disrupted lamin A/C and lamin B localization. Expression of U{sub L}34 and U{sub S}3 together had little effect on lamin A/C localization, suggesting a regulatory interaction between the two proteins. The data presented in this paper argue for crucial roles for both U{sub L}34 and U{sub S}3 in regulating the state of the nuclear lamina during viral infection.

Bjerke, Susan L. [Department of Microbiology, The University of Iowa, 3115 Medical Laboratories, Iowa City, IA 52242 (United States); Roller, Richard J. [Department of Microbiology, The University of Iowa, 3115 Medical Laboratories, Iowa City, IA 52242 (United States)]. E-mail: richard-roller@uiowa.edu

2006-04-10

394

Increased invasive behaviour in cutaneous squamous cell carcinoma with loss of basement-membrane type VII collagen.  

PubMed

Type VII collagen (ColVII) is the main component of anchoring fibrils, attachment structures within the lamina densa of the basement membrane that are responsible for attachment of the epidermis to the dermis in skin. Mutations in the human ColVII gene, COL7A1, cause the severe inherited blistering disorder recessive dystrophic epidermolysis bullosa (RDEB) affecting skin and mucosae, associated with a greatly increased risk of skin cancer. In this study, we examined the effect of loss of ColVII on squamous cell carcinoma (SCC) tumourigenesis using RNAi in a 3D organotypic skin model. Our findings suggest that loss of ColVII promotes SCC migration and invasion as well as regulating cell differentiation with evidence for concomitant promotion of epithelial-mesenchymal transition (EMT). Immunostaining of RDEB skin and a tissue array of sporadic cutaneous SCCs confirmed that loss of ColVII correlates with decreased involucrin expression in vivo. Gene-expression-array data and immunostaining demonstrated that loss of ColVII increases expression of the chemokine ligand-receptor CXCL10-CXCR3 and downstream-associated PLC signalling, which might contribute to the increased metastatic potential of SCCs with reduced or absent ColVII expression. Together, these findings may explain the aggressive behaviour of SCCs in RDEB patients and may also be relevant to non-RDEB skin cancer, as well as other tumours from organs where ColVII is expressed. PMID:19435799

Martins, Vera L; Vyas, Jashmin J; Chen, Mei; Purdie, Karin; Mein, Charles A; South, Andrew P; Storey, Alan; McGrath, John A; O'Toole, Edel A

2009-05-12

395

Human pathogens utilize host extracellular matrix proteins laminin and collagen for adhesion and invasion of the host.  

PubMed

Laminin (Ln) and collagen are multifunctional glycoproteins that play an important role in cellular morphogenesis, cell signalling, tissue repair and cell migration. These proteins are ubiquitously present in tissues as a part of the basement membrane (BM), constitute a protective layer around blood capillaries and are included in the extracellular matrix (ECM). As a component of BMs, both Lns and collagen(s), thus function as major mechanical containment molecules that protect tissues from pathogens. Invasive pathogens breach the basal lamina and degrade ECM proteins of interstitial spaces and connective tissues using various ECM-degrading proteases or surface-bound plasminogen and matrix metalloproteinases recruited from the host. Most pathogens associated with the respiratory, gastrointestinal, or urogenital tracts, as well as with the central nervous system or the skin, have the capacity to bind and degrade Lns and collagen(s) in order to adhere to and invade host tissues. In this review, we focus on the adaptability of various pathogens to utilize these ECM proteins as enhancers for adhesion to host tissues or as a targets for degradation in order to breach the cellular barriers. The major pathogens discussed are Streptococcus, Staphylococcus, Pseudomonas, Salmonella, Yersinia, Treponema, Mycobacterium, Clostridium, Listeria, Porphyromonas and Haemophilus; Candida, Aspergillus, Pneumocystis, Cryptococcus and Coccidioides; Acanthamoeba, Trypanosoma and Trichomonas; retrovirus and papilloma virus. PMID:22537156

Singh, Birendra; Fleury, Christophe; Jalalvand, Farshid; Riesbeck, Kristian

2012-06-18

396

Diagnosis of invasive candidiasis in the ICU  

PubMed Central

Invasive candidiasis ranges from 5 to 10 cases per 1,000 ICU admissions and represents 5% to 10% of all ICU-acquired infections, with an overall mortality comparable to that of severe sepsis/septic shock. A large majority of them are due to Candida albicans, but the proportion of strains with decreased sensitivity or resistance to fluconazole is increasingly reported. A high proportion of ICU patients become colonized, but only 5% to 30% of them develop an invasive infection. Progressive colonization and major abdominal surgery are common risk factors, but invasive candidiasis is difficult to predict and early diagnosis remains a major challenge. Indeed, blood cultures are positive in a minority of cases and often late in the course of infection. New nonculture-based laboratory techniques may contribute to early diagnosis and management of invasive candidiasis. Both serologic (mannan, antimannan, and betaglucan) and molecular (Candida-specific PCR in blood and serum) have been applied as serial screening procedures in high-risk patients. However, although reasonably sensitive and specific, these techniques are largely investigational and their clinical usefulness remains to be established. Identification of patients susceptible to benefit from empirical antifungal treatment remains challenging, but it is mandatory to avoid antifungal overuse in critically ill patients. Growing evidence suggests that monitoring the dynamic of Candida colonization in surgical patients and prediction rules based on combined risk factors may be used to identify ICU patients at high risk of invasive candidiasis susceptible to benefit from prophylaxis or preemptive antifungal treatment.

2011-01-01

397

Cell signaling during Trypanosoma cruzi invasion.  

PubMed

Cell signaling is an essential requirement for mammalian cell invasion by Trypanosoma cruzi. Depending on the parasite strain and the parasite developmental form, distinct signaling pathways may be induced. In this short review, we focus on the data coming from studies with metacyclic trypomastigotes (MT) generated in vitro and tissue culture-derived trypomastigotes (TCT), used as counterparts of insect-borne and bloodstream parasites, respectively. During invasion of host cells by MT or TCT, intracellular Ca(2) (+) mobilization and host cell lysosomal exocytosis are triggered. Invasion mediated by MT surface molecule gp82 requires the activation of mammalian target of rapamycin (mTOR), phosphatidylinositol 3-kinase (PI3K), and protein kinase C (PKC) in the host cell, associated with Ca(2) (+)-dependent disruption of the actin cytoskeleton. In MT, protein tyrosine kinase, PI3K, phospholipase C, and PKC appear to be activated. TCT invasion, on the other hand, does not rely on mTOR activation, rather on target cell PI3K, and may involve the host cell autophagy for parasite internalization. Enzymes, such as oligopeptidase B and the major T. cruzi cysteine proteinase cruzipain, have been shown to generate molecules that induce target cell Ca(2) (+) signal. In addition, TCT may trigger host cell responses mediated by transforming growth factor ? receptor or integrin family member. Further investigations are needed for a more complete and detailed picture of T. cruzi invasion. PMID:23230440

Maeda, Fernando Y; Cortez, Cristian; Yoshida, Nobuko

2012-11-28

398

Minimally Invasive Surgical Treatment of Esophageal Carcinoma  

PubMed Central

Surgical resection has proven successful in eradicating cancer of the esophagus, and it remains one of the main treatment modalities available for the curative management of patients with this disease. Unfortunately, patient morbidity is high because of the extensive nature of the surgery, which traditionally involves opening the chest and abdomen. Most time-honored techniques used to resect the esophagus and reconstruct the alimentary passage use the stomach as the replacement conduit, and a major abdominal dissection is therefore involved. Hoping to decrease the perioperative morbidity associated with esophagectomy, a number of thoracic surgeons have started to experiment with resection of the esophagus using aminimally invasive approach in select groups of patients. In minimally invasive esophagectomy (MIE), body cavities are accessed using a camera and fine, narrow instruments inserted through small incisions. Experience with abdominal surgery over the past decade suggests that a number of operative variables are improved using minimally invasive procedures, such as blood loss, rate of perioperative complications, and length of hospital stay. Data also suggest that the minimally invasive approach is comparable to or more advantageous than open procedures, in terms of both short- and long-term outcomes. Similarly, based on the limited data available today, shortterm outcomes after MIE are at least comparable with outcomes associated with open procedures. Minimally invasive resection of the esophagus for the management of esophageal cancer is feasible and safe. Whether MIE is better than traditional open techniques remains to be determined.

2008-01-01

399

Factors promoting marine invasions: A chemoecological approach  

PubMed Central

The Mediterranean Sea is losing its biological distinctiveness, and the same phenomenon is occurring in other seas. It gives urgency to a better understanding of the factors that affect marine biological invasions. A chemoecological approach is proposed here to define biotic conditions that promote biological invasions in terms of enemy escape and resource opportunities. Research has focused on the secondary metabolite composition of three exotic sea slugs found in Greece that have most probably entered the Mediterranean basin by Lessepsian migration, an exchange that contributes significantly to Mediterranean biodiversity. We have found toxic compounds with significant activity as feeding deterrents both in the cephalaspidean Haminoea cyanomarginata and in the nudibranch Melibe viridis. These findings led us to propose aposematism in the former and dietary autonomy in producing defensive metabolites in the latter case, as predisposing factors to the migration. In the third mollusk investigated, the anaspidean Syphonota geographica, the topic of marine invasions has been approached through a study of its feeding biology. The identification of the same compounds from both the viscera of each individual, separately analyzed, and their food, the seagrass Halophila stipulacea, implies a dietary dependency. The survival of S. geographica in the Mediterranean seems to be related to the presence of H. stipulacea. The initial invasion of this exotic pest would seem to have paved the way for the subsequent invasion of a trophic specialist that takes advantage of niche opportunities.

Mollo, Ernesto; Gavagnin, Margherita; Carbone, Marianna; Castelluccio, Francesco; Pozone, Ferdinando; Roussis, Vassilios; Templado, Jose; Ghiselin, Michael T.; Cimino, Guido

2008-01-01

400

Endemic predators, invasive prey and native diversity  

PubMed Central

Interactions between native diversity and invasive species can be more complex than is currently understood. Invasive ant species often substantially reduce diversity in the native ants diversity that act as natural control agents for pest insects. In Indonesia (on the island of Sulawesi), the third largest cacao producer worldwide, we show that a predatory endemic toad (Ingerophrynus celebensis) controls invasive ant (Anoplolepis gracilipes) abundance, and positively affects native ant diversity. We call this the invasive-naivety effect (an opposite of enemy release), whereby alien species may not harbour anti-predatory defences against a novel native predator. A positive effect of the toads on native ants may facilitate their predation on insect vectors of cacao diseases. Hence, toads may increase crop yield, but further research is needed on this aspect. Ironically, amphibians are globally the most threatened vertebrate class and are strongly impacted by the conversion of rainforest to cacao plantations in Sulawesi. It is, therefore, crucial to manage cacao plantations to maintain these endemic toads, as they may provide critical ecosystem services, such as invasion resistance and preservation of native insect diversity.

Wanger, Thomas C.; Wielgoss, Arno C.; Motzke, Iris; Clough, Yann; Brook, Barry W.; Sodhi, Navjot S.; Tscharntke, Teja

2011-01-01

401

Invasive Plant Atlas of New England  

NSDL National Science Digital Library

Many persons have grown increasingly concerned about various invasive species, and despite the scientific debates about what constitutes such a species, ecologists and others will find this site quite helpful. Drawing on support from the USDA, this project was developed by the Ecology and Evolutionary Biology Department of the University of Connecticut, the New England Wildflower Society, and several other participating organizations. This site includes a Web-accessible atlas that contains images and descriptive information for the invasive and potentially invasive plants in New England. Visitors can create their customized maps that document these species by utilizing the online records database, and also just search the species by geographic species. As a way of introduction, visitors can also browse a current list of species for which data has been collected thus far. Persons interested in volunteering for the project may also want to take a look at the volunteers section which lists the times of upcoming training sessions.

402

Modeling tumor invasion and metastasis in Drosophila  

PubMed Central

Conservation of major signaling pathways between humans and flies has made Drosophila a useful model organism for cancer research. Our understanding of the mechanisms regulating cell growth, differentiation and development has been considerably advanced by studies in Drosophila. Several recent high profile studies have examined the processes constraining the metastatic growth of tumor cells in fruit fly models. Cell invasion can be studied in the context of an in vivo setting in flies, enabling the genetic requirements of the microenvironment of tumor cells undergoing metastasis to be analyzed. This Perspective discusses the strengths and limitations of Drosophila models of cancer invasion and the unique tools that have enabled these studies. It also highlights several recent reports that together make a strong case for Drosophila as a system with the potential for both testing novel concepts in tumor progression and cell invasion, and for uncovering players in metastasis.

Miles, Wayne O.; Dyson, Nicholas J.; Walker, James A.

2011-01-01

403

Introduction: Minimally Invasive Spine Surgery video supplement.  

PubMed

This video supplement of Neurosurgery Focus is devoted to minimally invasive spine surgery. Minimally invasive spine surgery has gained popularity amongst patients and physicians over the past decade because it has been shown in select instances to lower blood loss and reduce length of hospital stay for appropriately selected candidates. This supplement includes videos from many of the leaders in the field. Pioneers like Frank LaMarca, Paul Park, Cheerag Upadhyaya, Juan Uribe, and Mike Wang have all sent in videos depicting minimally invasive spinal deformity surgery options. The supplement also includes videos from several different countries, demonstrating how widespread and nuanced minimally invasive spinal procedures have become. Drs. Barbagallo, Certo, Sciacca, and Albanese from Italy; Drs. Gragnaniello and Seex from Australia; and Drs. Liao, Wu, Huang, Wang, Chang, Cheng, and Shih from Taiwan have all sent in nuanced surgical videos that will be of interest to many viewers. I personally enjoyed viewing videos on lumbar degenerative disease surgery depicting unique surgical nuances to treat common problems. Dr. Beejal Amin, Dr. Harel Deutsch, Dr. Daniel Lu, and Dr. Adam Kanter have each submitted videos depicting lumbar decompression and/or fusion for lumbar degenerative stenosis and spondylosis. This supplement also included videos depicting the minimally invasive treatment of uncommon spinal pathologies as well. Videos from Dr. Fred Geisler, Dr. John O'Toole, and Dr. Noel Perin covered topics as varied as sacroiliac joint dysfunction, spinal arteriovenous malformations, and sympathetic chain surgery. I hope that you enjoy this issue of Neurosurgical Focus devoted to videos depicting the surgical nuances of minimally invasive spinal surgery. This video supplement has international appeal, and it has been an honor to be a guest editor on this superb supplement. PMID:23829838

Mummaneni, Praveen V

2013-07-01

404

Non-Invasive markers for hepatic fibrosis  

PubMed Central

With great advancements in the therapeutic modalities used for the treatment of chronic liver diseases, the accurate assessment of liver fibrosis is a vital need for successful individualized management of disease activity in patients. The lack of accurate, reproducible and easily applied methods for fibrosis assessment has been the major limitation in both the clinical management and for research in liver diseases. However, the problem of the development of biomarkers capable of non-invasive staging of fibrosis in the liver is difficult due to the fact that the process of fibrogenesis is a component of the normal healing response to injury, invasion by pathogens, and many other etiologic factors. Current non-invasive methods range from serum biomarker assays to advanced imaging techniques such as transient elastography and magnetic resonance imaging (MRI). Among non-invasive methods that gain strongest clinical foothold are FibroScan elastometry and serum-based APRI and FibroTest. There are many other tests that are not yet widely validated, but are none the less, promising. The rate of adoption of non-invasive diagnostic tests for liver fibrosis differs from country to country, but remains limited. At the present time, use of non-invasive procedures could be recommended as pre-screening that may allow physicians to narrow down the patients' population before definitive testing of liver fibrosis by biopsy of the liver. This review provides a systematic overview of these techniques, as well as both direct and indirect biomarkers based approaches used to stage fibrosis and covers recent developments in this rapidly advancing area.

2011-01-01

405

Riparian invasive alters stream nitrogen dynamics.  

NASA Astrophysics Data System (ADS)

Invasive species may be most likely to have strong effects on the ecosystem they invade when they contribute a new function such as nitrogen (N) fixation. Russian olive (Eleagnus angustifolia) is a non-native invasive tree which is rapidly spreading along riparian corridors in the American West. Russian olive is a nitrogen fixing plant due to a symbiotic relationship with Actinomycetes and is invading systems that frequently lack a strong native N fixer. The contribution of reactive N by these invasive riparian plants to soils may also be altering N cycling and processing in the adjacent streams. We measured nutrient limitation via periphyton growth on nutrient diffusing substrates and nitrate uptake using short term nitrate additions in Deep Creek, ID. Measurements were made in three reaches along a Russian olive invasion gradient, with an upstream reference reach that has no Russian olive and two downstream invaded reaches, one with moderate density and one with high density. Periphyton growth in Deep Creek was significantly N limited in the reference reach while the moderately invaded reach showed no significant limitation and the highly invaded reach was significantly P limited. The nitrate uptake velocity (Vf) for both of the invaded reaches was an order of magnitude less than the reference reach, implying that biological demand for nitrate is significantly less in the invaded reaches than the reference. Considering the current extent of Russian olive invasion and its continued rapid spread, possible alteration of N cycling in waterways may have important implications for the management of both this invasive species and management of nutrient pollution in waters of the western U.S.

Mineau, M.; Baxter, C.; Marcarelli, A.; Minshall, G.

2008-12-01

406

Systematic Review of Minimally Invasive Pancreatic Resection  

Microsoft Academic Search

Background  Pancreatic resection is associated with a significant morbidity. Efforts to reduce hospital stay and enhance recovery have\\u000a seen the introduction of minimally invasive surgical techniques. This article reviews the current published literature on\\u000a the safety and efficacy of minimally invasive surgery of the pancreas.\\u000a \\u000a \\u000a \\u000a Methods  An electronic search of the PubMed and Embase databases was performed from 1996 to May 2008

Christopher D. Briggs; Christopher D. Mann; Glen R. B. Irving; Christopher P. Neal; Mark Peterson; Iain C. Cameron; David P. Berry

2009-01-01

407

Maximizing the benefit of minimally invasive surgery.  

PubMed

Minimal invasive surgery is an excellent approach for the diagnosis and treatment of a wide range of thoracic disorders that previously required sternotomy or open thoracotomy. The notable benefits of minimal invasive surgery to patients include less postoperative pain, fewer operative and post-operative major complications, shortened hospital stay, faster recovery times, less scarring, less stress on the immune system, smaller incision, and for some procedures reduced operating time and reduced costs. J. Surg. Oncol. 2013 108:315-319. © 2013 Wiley Periodicals, Inc. PMID:24037974

Mohiuddin, Kamran; Swanson, Scott J

2013-08-23

408

Percutaneous & Mini Invasive Achilles tendon repair  

PubMed Central

Rupture of the Achilles tendon is a considerable cause of morbidity with reduced function following injury. Recent studies have shown little difference in outcome between the techniques of open and non-operative treatment using an early active rehabilitation programme. Meta-analyses have shown that non-operative management has increased risk of re-rupture whereas surgical intervention has risks of complications related to the wound and iatrogenic nerve injury. Minimally invasive surgery has been adopted as a way of reducing infections rates and wound breakdown however avoiding iatrogenic nerve injury must be considered. We discuss the techniques and outcomes of percutaneous and minimally invasive repairs of the Achilles tendon.

2011-01-01

409

Measurement of invasive blood pressure in rats  

PubMed Central

Blood pressure (BP) is one of the vital parameters used to assess the cardiovascular functions of a mammal. BP is commonly recorded using invasive, noninvasive, and radio telemetry methods, but invasive blood pressure (IBP) recording is considered the gold standard. IBP provides a direct indication of the effect of the investigational products on the circulatory system. Recording the IBP in rodents is an essential part of the preliminary screening of any product to determine its effect on the cardiovascular system. The present article describes the measurement of the IBP in Wistar rats/Sprague Dawley rats.

Parasuraman, Subramani; Raveendran, Ramasamy

2012-01-01

410

Directed Cell Invasion and Migration During Metastasis  

PubMed Central

Metastasis requires tumor cell dissemination to different organs from the primary tumor. Dissemination is a complex cell motility phenomenon that requires the molecular coordination of the protrusion, chemotaxis, invasion and contractility activities of tumor cells to achieve directed cell migration. Recent studies of the spatial and temporal activities of the small GTPases have begun to elucidate how this coordination is achieved. The direct visualization of the pathways involved in actin polymerization, invasion and directed migration in dissemination competent tumor cells will help identify the molecular basis of dissemination and allow the design and testing of more specific and selective drugs to block metastasis.

Bravo-Cordero, Jose Javier; Hodgson, Louis; Condeelis, John

2011-01-01

411

Minimally invasive transhiatal esophagectomy after thoracotomy.  

PubMed

Patients with end-stage achalasia may not be candidates for a transhiatal minimally invasive esophageal resection because of anatomic challenges and adhesions from previous interventions, namely, thoracotomy. Given the tactile feedback provided through a GelPort laparoscopic system (Applied Medical, Rancho Margarita, CA) we proposed that a minimally invasive transhiatal esophagectomy would be feasible in this patient cohort. The procedure was successful in 4 patients; seven complications occurred in 3 of the patients. At follow-up all patients demonstrated that they were meeting their nutritional needs with an oral diet. PMID:23336915

Carter, Yvonne M; Bond, Colleen D; Benjamin, Stanley; Marshall, M Blair

2013-02-01

412

Invasive and non-invasive measurement in medicine and biology: calibration issues  

NASA Astrophysics Data System (ADS)

Invasive and non-invasive measurement sensors and systems perform vital roles in medical care. Devices are based on various principles, including optics, photonics, and plasmonics, electro-analysis, magnetics, acoustics, bio-recognition, etc. Sensors are used for the direct insertion into the human body, for example to be in contact with blood, which constitutes Invasive Measurement. This approach is very challenging technically, as sensor performance (sensitivity, response time, linearity) can deteriorate due to interactions between the sensor materials and the biological environment, such as blood or interstitial fluid. Invasive techniques may also be potentially hazardous. Alternatively, sensors or devices may be positioned external to the body surface, for example to analyse respired breath, thereby allowing safer Non-Invasive Measurement. However, such methods, which are inherently less direct, often requiring more complex calibration algorithms, perhaps using chemometric principles. This paper considers and reviews the issue of calibration in both invasive and non-invasive biomedical measurement systems. Systems in current use usually rely upon periodic calibration checks being performed by clinical staff against a variety of laboratory instruments and QC samples. These procedures require careful planning and overall management if reliable data are to be assured.

Rolfe, P.; Zhang, Yan; Sun, Jinwei; Scopesi, F.; Serra, G.; Yamakoshi, K.; Tanaka, S.; Yamakoshi, T.; Yamakoshi, Y.; Ogawa, M.

2010-08-01

413

Intracranial Pressure Monitoring: Invasive versus Non-Invasive Methods--A Review  

PubMed Central

Monitoring of intracranial pressure (ICP) has been used for decades in the fields of neurosurgery and neurology. There are multiple techniques: invasive as well as noninvasive. This paper aims to provide an overview of the advantages and disadvantages of the most common and well-known methods as well as assess whether noninvasive techniques (transcranial Doppler, tympanic membrane displacement, optic nerve sheath diameter, CT scan/MRI and fundoscopy) can be used as reliable alternatives to the invasive techniques (ventriculostomy and microtransducers). Ventriculostomy is considered the gold standard in terms of accurate measurement of pressure, although microtransducers generally are just as accurate. Both invasive techniques are associated with a minor risk of complications such as hemorrhage and infection. Furthermore, zero drift is a problem with selected microtransducers. The non-invasive techniques are without the invasive methods' risk of complication, but fail to measure ICP accurately enough to be used as routine alternatives to invasive measurement. We conclude that invasive measurement is currently the only option for accurate measurement of ICP.

Raboel, P. H.; Bartek, J.; Andresen, M.; Bellander, B. M.; Romner, B.

2012-01-01

414

Bcl-w promotes cell invasion by blocking the invasion-suppressing action of Bax.  

PubMed

The Bcl-2 family members are key regulators of cellular viability, either promoting or suppressing cell death. Recent reports have indicated that the pro-survival members (Bcl-w, Bcl-XL, and others) also enhance the migratory and invasive potentials of cancer cells, although the mechanisms underlying this phenomenon have yet to be adequately elucidated. Herein, by using human cancer cells and mouse embryonic fibroblasts, we demonstrate that Bcl-w functions in the mitochondria to increase the levels of reactive oxygen species (ROS), which subsequently stimulates the invasion-promoting signaling pathway. By way of contrast, Bax,a member of the multidomain pro-apoptotic group (Bax and Bak), was found to reduce ROS levels, thereby suppressing cell invasion. Analyses of the functional relationship between Bcl-w and Bax have shown that Bcl-w requires Bax for promoting cell invasion, whereas Bax suppresses cell invasion in a Bcl-win dependent manner. By using a Bcl-w mutant (Bcl-w/G94A) that was found not to bind to Bax, we have further determined that Bcl-w should bind to Bax to promote cell invasion. Overall, the results indicate that Bcl-w enhances cellular invasiveness by binding to Bax and subsequently blocking its invasion suppressing actions. Moreover, these functions of Bcl-w and Bax are mimicked by other pro-survival and pro-apoptotic members, such as Bcl-XL and Bak, respectively. We propose the balance between prosurvival and multidomain pro-apoptotic members as a novel determinant of cellular invasiveness. PMID:22570867

Kim, Eun Mi; Kim, Jongdoo; Park, Jong Kuk; Hwang, Sang-Gu; Kim, Wun-Jae; Lee, Won-Jae; Kang, Sang Won; Um, Hong-Duck

2012-06-01

415

Cell biology and invasion of the microsporidia.  

PubMed

Microsporidia are amitochondrial eukaryotic obligate intracellular parasites. They are reported to infect every animal group from protists to vertebrates, including humans. Microsporidia are of interest as opportunistic pathogens in humans and for certain characteristics which raise questions about their evolution and phylogenetic position. This review describes the basic biology and invasion mechanisms of microsporidian species infecting humans. PMID:11369274

Bigliardi, E; Sacchi, L

2001-04-01

416

Endogent: Centre for Anatomy and Invasive Techniques  

Microsoft Academic Search

The invention of new endoscopical techniques for surgery and interventional radiology demand improved training at post- graduate level. The Endogent Centre for Anatomy and Invasive Techniques support these requirements by establishing hands-on practical training courses by using new procedures for cadaver embalming. Cadavers fixed by conventional pro- cedures using formalin for conservation, are of limited use for practical surgical courses

Ingrid Kerckaert; Tom Van Hoof; Piet Pattyn; Katharina D'Herde

2008-01-01

417

Seasonal Patterns of Invasive Pneumococcal Disease  

Microsoft Academic Search

Pneumococcal infections increase each winter, a phe- nomenon that has not been well explained. We conducted population-based active surveillance for all cases of inva- sive pneumococcal disease in seven states; plotted annu- alized weekly rates by geographic location, age, and lati- tude; and assessed correlations by time-series analysis. In all geographic areas, invasive pneumococcal disease exhibited a distinct winter seasonality,

Scott F. Dowell; Cynthia G. Whitney; Carolyn Wright; Charles E. Rose; Anne Schuchat

2003-01-01

418

EXOTIC AND INVASIVE HERBACEOUS RANGE WEEDS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Resource managers are often discouraged when it comes to the identification of herbaceous rangeland weeds, terminology associated with these weeds, control of these weeds, and the succession of these weeds. The terminology often used in describing herbaceous rangeland weeds (i. e. invasive) often m...

419

Invasion Ecology (Teacher's Guide) (e-book)  

NSDL National Science Digital Library

Strange intruders are invading our part of the world, threatening our environment and our economy. These newcomers and their impact on our ecological balance are the focus of Invasion Ecology, a new book that teaches students to investigate the behaviors of nonnative and native species. Studying real-life invaders such as purple loosestrife and Phragmites, students will learn about the links between biology and ecology -- and explore how scientists are fighting these aggressors with biological controls. The Teacher's Edition explains how to guide highly sophisticated inquiry and conduct interactive research. Materials are classroom-ready and include detailed background information as well as sample assessment tasks and rubrics.The companion Student Edition has three sections: � Background on the science of ecology and its place in the control of invasive species � Protocols for practicing methods that scientists use in monitoring invasive species, such as early detection surveys, plot sampling, transect surveys, and decomposition studies � A series of helpful worksheets to guide students through their own interactive research Invasion Ecology is the second volume in the four-part Environmental Inquiry curriculum series, designed to show students how to apply scientific knowledge to solving real-life problems.

Krasny, Marianne E.; Team, The E.

1900-01-01

420

Minimally invasive surgical training: Challenges and solutions  

Microsoft Academic Search

Treatment options for urological malignancies continue to increase and include endoscopic, laparoscopic, robotic, and image-guided percutaneous techniques. This ever expanding array of technically demanding management options coupled with a static training paradigm introduces challenges to training the urological oncologist of the future. Minimally invasive learning opportunities continue to evolve, and include an intensive experience during residency, postgraduate short courses or

Phillip M. Pierorazio; Mohamad E. Allaf

2009-01-01