Sample records for abscission zone cells

  1. Cell Wall Remodeling in Abscission Zone Cells during Ethylene-Promoted Fruit Abscission in Citrus

    PubMed Central

    Merelo, Paz; Agustí, Javier; Arbona, Vicent; Costa, Mário L.; Estornell, Leandro H.; Gómez-Cadenas, Aurelio; Coimbra, Silvia; Gómez, María D.; Pérez-Amador, Miguel A.; Domingo, Concha; Talón, Manuel; Tadeo, Francisco R.

    2017-01-01

    Abscission is a cell separation process by which plants can shed organs such as fruits, leaves, or flowers. The process takes place in specific locations termed abscission zones. In fruit crops like citrus, fruit abscission represents a high percentage of annual yield losses. Thus, understanding the molecular regulation of abscission is of capital relevance to control production. To identify genes preferentially expressed within the citrus fruit abscission zone (AZ-C), we performed a comparative transcriptomics assay at the cell type resolution level between the AZ-C and adjacent fruit rind cells (non-abscising tissue) during ethylene-promoted abscission. Our strategy combined laser microdissection with microarray analysis. Cell wall modification-related gene families displayed prominent representation in the AZ-C. Phylogenetic analyses of such gene families revealed a link between phylogenetic proximity and expression pattern during abscission suggesting highly conserved roles for specific members of these families in abscission. Our transcriptomic data was validated with (and strongly supported by) a parallel approach consisting on anatomical, histochemical and biochemical analyses on the AZ-C during fruit abscission. Our work identifies genes potentially involved in organ abscission and provides relevant data for future biotechnology approaches aimed at controlling such crucial process for citrus yield. PMID:28228766

  2. Separation of abscission zone cells in detached Azolla roots depends on apoplastic pH.

    PubMed

    Fukuda, Kazuma; Yamada, Yoshiya; Miyamoto, Kensuke; Ueda, Junichi; Uheda, Eiji

    2013-01-01

    In studies on the mechanism of cell separation during abscission, little attention has been paid to the apoplastic environment. We found that the apoplastic pH surrounding abscission zone cells in detached roots of the water fern Azolla plays a major role in cell separation. Abscission zone cells of detached Azolla roots were separated rapidly in a buffer at neutral pH and slowly in a buffer at pH below 4.0. However, cell separation rarely occurred at pH 5.0-5.5. Light and electron microscopy revealed that cell separation was caused by a degradation of the middle lamella between abscission zone cells at both pH values, neutral and below 4.0. Low temperature and papain treatment inhibited cell separation. Enzyme(s) in the cell wall of the abscission zone cells might be involved in the degradation of the pectin of the middle lamella and the resultant, pH-dependent cell separation. By contrast, in Phaseolus leaf petioles, unlike Azolla roots, cell separation was slow and increased only at acidic pH. The rapid cell separation, as observed in Azolla roots at neutral pH, did not occur. Indirect immunofluorescence microscopy, using anti-pectin monoclonal antibodies, revealed that the cell wall pectins of the abscission zone cells of Azolla roots and Phaseolus leaf petioles looked similar and changed similarly during cell separation. Thus, the pH-related differences in cell separation mechanisms of Azolla and Phaseolus might not be due to differences in cell wall pectin, but to differences in cell wall-located enzymatic activities responsible for the degradation of pectic substances. A possible enzyme system is discussed. Copyright © 2012 Elsevier GmbH. All rights reserved.

  3. A new aspect of flower abscission: involvement of a specific alkalization of the cytosol in the abscission zone cells

    USDA-ARS?s Scientific Manuscript database

    The correlation between organ abscission and pH changes in the abscission zone (AZ) cells, visualized by the pH-sensitive and intracellularly trapped dye, 2',7'-bis-(2-carboxyethyl)-5(and-6)-carboxyfluorescein-acetoxymethyl (BCECF-AM) ester derivative, combined with confocal microscopy was studied. ...

  4. Abscission of flowers and floral organs is closely associated with alkalization of the cytosol in abscission zone cells

    PubMed Central

    Sundaresan, Srivignesh; Philosoph-Hadas, Sonia; Riov, Joseph; Belausov, Eduard; Kochanek, Betina; Tucker, Mark L.; Meir, Shimon

    2015-01-01

    In vivo changes in the cytosolic pH of abscission zone (AZ) cells were visualized using confocal microscopic detection of the fluorescent pH-sensitive and intracellularly trapped dye, 2’,7’-bis-(2-carboxyethyl)-5(and-6)-carboxyfluorescein (BCECF), driven by its acetoxymethyl ester. A specific and gradual increase in the cytosolic pH of AZ cells was observed during natural abscission of flower organs in Arabidopsis thaliana and wild rocket (Diplotaxis tenuifolia), and during flower pedicel abscission induced by flower removal in tomato (Solanum lycopersicum Mill). The alkalization pattern in the first two species paralleled the acceleration or inhibition of flower organ abscission induced by ethylene or its inhibitor 1-methylcyclopropene (1-MCP), respectively. Similarly, 1-MCP pre-treatment of tomato inflorescence explants abolished the pH increase in AZ cells and pedicel abscission induced by flower removal. Examination of the pH changes in the AZ cells of Arabidopsis mutants defective in both ethylene-induced (ctr1, ein2, eto4) and ethylene-independent (ida, nev7, dab5) abscission pathways confirmed these results. The data indicate that the pH changes in the AZ cells are part of both the ethylene-sensitive and -insensitive abscission pathways, and occur concomitantly with the execution of organ abscission. pH can affect enzymatic activities and/or act as a signal for gene expression. Changes in pH during abscission could occur via regulation of transporters in AZ cells, which might affect cytosolic pH. Indeed, four genes associated with pH regulation, vacuolar H+-ATPase, putative high-affinity nitrate transporter, and two GTP-binding proteins, were specifically up-regulated in tomato flower AZ following abscission induction, and 1-MCP reduced or abolished the increased expression. PMID:25504336

  5. Abscission of flowers and floral organs is closely associated with alkalization of the cytosol in abscission zone cells.

    PubMed

    Sundaresan, Srivignesh; Philosoph-Hadas, Sonia; Riov, Joseph; Belausov, Eduard; Kochanek, Betina; Tucker, Mark L; Meir, Shimon

    2015-03-01

    In vivo changes in the cytosolic pH of abscission zone (AZ) cells were visualized using confocal microscopic detection of the fluorescent pH-sensitive and intracellularly trapped dye, 2',7'-bis-(2-carboxyethyl)-5(and-6)-carboxyfluorescein (BCECF), driven by its acetoxymethyl ester. A specific and gradual increase in the cytosolic pH of AZ cells was observed during natural abscission of flower organs in Arabidopsis thaliana and wild rocket (Diplotaxis tenuifolia), and during flower pedicel abscission induced by flower removal in tomato (Solanum lycopersicum Mill). The alkalization pattern in the first two species paralleled the acceleration or inhibition of flower organ abscission induced by ethylene or its inhibitor 1-methylcyclopropene (1-MCP), respectively. Similarly, 1-MCP pre-treatment of tomato inflorescence explants abolished the pH increase in AZ cells and pedicel abscission induced by flower removal. Examination of the pH changes in the AZ cells of Arabidopsis mutants defective in both ethylene-induced (ctr1, ein2, eto4) and ethylene-independent (ida, nev7, dab5) abscission pathways confirmed these results. The data indicate that the pH changes in the AZ cells are part of both the ethylene-sensitive and -insensitive abscission pathways, and occur concomitantly with the execution of organ abscission. pH can affect enzymatic activities and/or act as a signal for gene expression. Changes in pH during abscission could occur via regulation of transporters in AZ cells, which might affect cytosolic pH. Indeed, four genes associated with pH regulation, vacuolar H(+)-ATPase, putative high-affinity nitrate transporter, and two GTP-binding proteins, were specifically up-regulated in tomato flower AZ following abscission induction, and 1-MCP reduced or abolished the increased expression. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  6. Transcriptome Analysis of Tomato Flower Pedicel Tissues Reveals Abscission Zone-Specific Modulation of Key Meristem Activity Genes

    PubMed Central

    Sun, Xiuli; Zhang, Rongzhi; Wu, Liang; Liang, Yanchun; Mao, Long

    2013-01-01

    Tomato flower abscises at the anatomically distinct abscission zone that separates the pedicel into basal and apical portions. During abscission, cell separation occurs only at the abscission zone indicating distinctive molecular regulation in its cells. We conducted a transcriptome analysis of tomato pedicel tissues during ethylene promoted abscission. We found that the abscission zone was the most active site with the largest set of differentially expressed genes when compared with basal and apical portions. Gene Ontology analyses revealed enriched transcription regulation and hydrolase activities in the abscission zone. We also demonstrate coordinated responses of hormone and cell wall related genes. Besides, a number of ESTs representing homologs of key Arabidopsis shoot apical meristem activity genes were found to be preferentially expressed in the abscission zone, including WUSCHEL (WUS), KNAT6, LATERAL ORGAN BOUNDARIES DOMAIN PROTEIN 1(LBD1), and BELL-like homeodomain protein 1 (BLH1), as well as tomato axillary meristem genes BLIND (Bl) and LATERAL SUPPRESSOR (Ls). More interestingly, the homologs of WUS and the potential functional partner OVATE FAMILIY PROTEIN (OFP) were subsequently down regulated during abscission while Bl and AGL12 were continuously and specifically induced in the abscission zone. The expression patterns of meristem activity genes corroborate the idea that cells of the abscission zone confer meristem-like nature and coincide with the course of abscission and post-abscission cell differentiation. Our data therefore propose a possible regulatory scheme in tomato involving meristem genes that may be required not only for the abscission zone development, but also for abscission. PMID:23390523

  7. Comparative transcriptional survey between laser-microdissected cells from laminar abscission zone and petiolar cortical tissue during ethylene-promoted abscission in citrus leaves

    PubMed Central

    Agustí, Javier; Merelo, Paz; Cercós, Manuel; Tadeo, Francisco R; Talón, Manuel

    2009-01-01

    Background Abscission is the cell separation process by which plants are able to shed organs. It has a great impact on the yield of most crop plants. At the same time, the process itself also constitutes an excellent model to study cell separation processes, since it occurs in concrete areas known as abscission zones (AZs) which are composed of a specific cell type. However, molecular approaches are generally hampered by the limited area and cell number constituting the AZ. Therefore, detailed studies at the resolution of cell type are of great relevance in order to accurately describe the process and to identify potential candidate genes for biotechnological applications. Results Efficient protocols for the isolation of specific citrus cell types, namely laminar abscission zone (LAZ) and petiolar cortical (Pet) cells based on laser capture microdissection (LCM) and for RNA microextraction and amplification have been developed. A comparative transcriptome analysis between LAZ and Pet from citrus leaf explants subjected to an in-vitro 24 h ethylene treatment was performed utilising microarray hybridization and analysis. Our analyses of gene functional classes differentially represented in ethylene-treated LAZ revealed an activation program dominated by the expression of genes associated with protein synthesis, protein fate, cell type differentiation, development and transcription. The extensive repertoire of genes associated with cell wall biosynthesis and metabolism strongly suggests that LAZ layers activate both catabolic and anabolic wall modification pathways during the abscission program. In addition, over-representation of particular members of different transcription factor families suggests important roles for these genes in the differentiation of the effective cell separation layer within the many layers contained in the citrus LAZ. Preferential expression of stress-related and defensive genes in Pet reveals that this tissue is likely to be reprogrammed to

  8. Expression profiling of tomato pre-abscission pedicels provides insights into abscission zone properties including competence to respond to abscission signals

    PubMed Central

    2013-01-01

    Background Detachment of plant organs occurs in abscission zones (AZs). During plant growth, the AZ forms, but does not develop further until the cells perceive abscission-promoting signals and initiate detachment. Upon signal perception, abscission initiates immediately; if there is no signal, abscission is not induced and the organ remains attached to the plant. However, little attention has been paid to the genes that maintain competence to respond to the abscission signal in the pre-abscission AZ. Recently, we found that the tomato (Solanum lycopersicum) transcription factors BLIND (Bl), GOBLET (GOB), Lateral suppressor (Ls) and a tomato WUSCHEL homologue (LeWUS) are expressed specifically in pre-abscission tissue, the anthesis pedicel AZs. To advance our understanding of abscission, here we profiled genome-wide gene expression in tomato flower pedicels at the pre-abscission stage. Results We examined the transcriptomes of three tomato flower pedicel regions, the AZ and flanking proximal- (Prox) and distal- (Dis) regions, and identified 89 genes that were preferentially expressed in the AZ compared to both Prox and Dis. These genes included several transcription factors that regulate apical or axillary shoot meristem activity. Also, genes associated with auxin activity were regulated in a Prox-Dis region-specific manner, suggesting that a gradient of auxin exists in the pedicel. A MADS-box gene affecting floral transition was preferentially expressed in the Prox region and other MADS-box genes for floral organ identification were preferentially expressed in Dis, implying that the morphologically similar Prox and Dis regions have distinct identities. We also analyzed the expression of known regulators; in anthesis pedicels, Bl, GOB, Ls and LeWUS were expressed in the vascular cells of the AZ region. However, after an abscission signal, Bl was up-regulated, but GOB, Ls and LeWUS were down-regulated, suggesting that Bl may be a positive regulator of abscission

  9. Ethephon induced oxidative stress in the olive leaf abscission zone enables development of a selective abscission compound.

    PubMed

    Goldental-Cohen, S; Burstein, C; Biton, I; Ben Sasson, S; Sadeh, A; Many, Y; Doron-Faigenboim, A; Zemach, H; Mugira, Y; Schneider, D; Birger, R; Meir, S; Philosoph-Hadas, S; Irihomovitch, V; Lavee, S; Avidan, B; Ben-Ari, G

    2017-05-16

    Table olives (Olea europaea L.), despite their widespread production, are still harvested manually. The low efficiency of manual harvesting and the rising costs of labor have reduced the profitability of this crop. A selective abscission treatment, inducing abscission of fruits but not leaves, is crucial for the adoption of mechanical harvesting of table olives. In the present work we studied the anatomical and molecular differences between the three abscission zones (AZs) of olive fruits and leaves. The fruit abscission zone 3 (FAZ3), located between the fruit and the pedicel, was found to be the active AZ in mature fruits and is sensitive to ethephon, whereas FAZ2, between the pedicel and the rachis, is the flower active AZ as well as functioning as the most ethephon induced fruit AZ. We found anatomical differences between the leaf AZ (LAZ) and the two FAZs. Unlike the FAZs, the LAZ is characterized by small cells with less pectin compared to neighboring cells. In an attempt to differentiate between the fruit and leaf AZs, we examined the effect of treating olive-bearing trees with ethephon, an ethylene-releasing compound, with or without antioxidants, on the detachment force (DF) of fruits and leaves 5 days after the treatment. Ethephon treatment enhanced pectinase activity and reduced DF in all the three olive AZs. A transcriptomic analysis of the three olive AZs after ethephon treatment revealed induction of several genes encoding for hormones (ethylene, auxin and ABA), as well as for several cell wall degrading enzymes. However, up-regulation of cellulase genes was found only in the LAZ. Many genes involved in oxidative stress were induced by the ethephon treatment in the LAZ alone. In addition, we found that reactive oxygen species (ROS) mediated abscission in response to ethephon only in leaves. Thus, adding antioxidants such as ascorbic acid or butyric acid to the ethephon inhibited leaf abscission but enhanced fruit abscission. Our findings suggest that

  10. ASYMMETRIC LEAVES1 regulates abscission zone placement in Arabidopsis flowers

    PubMed Central

    2014-01-01

    Background The sepals, petals and stamens of Arabidopsis flowers detach via abscission zones formed at their boundaries with the underlying receptacle. The ASYMMETRIC LEAVES1 (AS1) MYB transcription factor plays a critical role in setting boundaries between newly formed leaf primordia and the shoot meristem. By repressing expression of a set of KNOTTED1-LIKE HOMEODOMAIN (KNOX) genes from developing leaf primordia, AS1 and its partner ASYMMETRIC LEAVES2 allow the patterning and differentiation of leaves to proceed. Here we show a unique role for AS1 in establishing the positions of the sepal and petal abscission zones in Arabidopsis flowers. Results In as1 mutant flowers, the sepal abscission zones are displaced into inverted V-shaped positions, leaving behind triangular stubs of tissue when the organs abscise. Movement of the petal abscission zones is also apparent. Abscission of the medial sepals is delayed in as1 flowers; loss of chlorophyll in the senescing sepals contrasts with proximal zones that remain green. AS1 has previously been shown to restrict expression of the KNOX gene, BREVIPEDICELLUS (BP), from the sepals. We show here that loss of BP activity in as1 flowers is sufficient to restore the positions of the sepal and petal abscission zones, the sepal-receptacle boundary of the medial sepals and the timing of their abscission. Conclusions Our results indicate that AS1 activity is critical for the proper placement of the floral organ abscission zones, and influences the timing of organ shedding. PMID:25038814

  11. Visualizing Morphological Changes of Abscission Zone Cells in Arabidopsis by Scanning Electron Microscope.

    PubMed

    Shi, Chun-Lin; Butenko, Melinka A

    2018-01-01

    Scanning electron microscope (SEM) is a type of electron microscope which produces detailed images of surface structures. It has been widely used in plants and animals to study cellular structures. Here, we describe a detailed protocol to prepare samples of floral abscission zones (AZs) for SEM, as well as further image analysis. We show that it is a powerful tool to detect morphologic changes at the cellular level during the course of abscission in wild-type plants and to establish the details of phenotypic alteration in abscission mutants.

  12. Microarray analysis of the abscission-related transcriptome in tomato flower abscission zone in response to auxin depletion

    USDA-ARS?s Scientific Manuscript database

    Abscission, the separation of organs from the parent plant, results in postharvest quality loss in many fresh produce. The process is initiated by changes in the auxin gradient across the abscission zone (AZ), is triggered by ethylene and may be accelerated by postharvest stresses. Although changes ...

  13. Breakdown of middle lamella pectin by (●) OH during rapid abscission in Azolla.

    PubMed

    Yamada, Yoshiya; Koibuchi, Mizuki; Miyamoto, Kensuke; Ueda, Junichi; Uheda, Eiji

    2015-08-01

    Azolla, a small water fern, abscises its roots and branches within 30 min upon treatment with various stresses. This study was conducted to test whether, in the rapid abscission that occurs in Azolla, breakdown of wall components of abscission zone cells by (●) OH is involved. Experimentally generated (●) OH caused the rapid separation of abscission zone cells from detached roots and the rapid shedding of roots from whole plants. Electron microscopic observations revealed that (●) OH rapidly and selectively dissolved a well-developed middle lamella between abscission zone cells and resultantly caused rapid cell separation and shedding. Treatment of abscission zones of Impatiens leaf petiole with (●) OH also accelerated the separation of abscission zone cells. However, compared with that of Azolla roots, accelerative effects in Impatiens were weak. A large amount of (●) OH was cytochemically detected in abscission zone cells both of Azolla roots and of Impatiens leaf petioles. These results suggest that (●) OH is involved in the cell separation process not only in the rapid abscission in Azolla but also in the abscission of Impatiens. However, for rapid abscission to occur, a well-developed middle lamella, a unique structure, which is sensitive to the attack of (●) OH, might be needed. © 2015 John Wiley & Sons Ltd.

  14. A Role for the Stele in Intertissue Signaling in the Initiation of Abscission in Bean Leaves (Phaseolus vulgaris L.).

    PubMed Central

    Thompson, D. S.; Osborne, D. J.

    1994-01-01

    A combination of microdissection and viscometric endo-[beta]-1,4-glucanhydrolase assays was used to investigate if the early appearance of the abscission-related isoelectric point-9.5 endo-[beta]-1,4-glucanhydrolase in the stele of the pulvinus and abscission zone of the foliar abscission zone of Phaseolus vulgaris L. prior to cell separation (reported by E. del Campillo, P.D. Reid, R. Sexton, L.N.Lewis [1990] Plant Cell 2: 245-254) indicates that the vascular tissue of this region has a specific role in abscission. We find that no endo-[beta]-1,4-glucanhydrolase activity or cell separation is detectable in the abscission zone cortex if the abscission zone cortex is separated from the stele tissue. If the stele is separated from the abscission zone cortex after a lag period but again before any endo-[beta]-1,4-glucanhydrolase activity is present in the abscission zone cortex, then the enzyme is produced in the cortex and abscission ensues. We conclude that the cortex of the abscission zone is able to abscind independently of the vascular tissue only after the vascular tissue has begun to respond to abscission-promoting signals. We suggest that ethylene promotes formation of an abscission-permitting signal in the stele of the abscission zone and pulvinus, and that this signal is an essential elicitor for the synthesis of cell separation enzymes in the target cells of the abscission zone cortex. PMID:12232206

  15. Ethylene-induced differential gene expression during abscission of citrus leaves

    PubMed Central

    Merelo, Paz; Cercós, Manuel; Tadeo, Francisco R.; Talón, Manuel

    2008-01-01

    The main objective of this work was to identify and classify genes involved in the process of leaf abscission in Clementina de Nules (Citrus clementina Hort. Ex Tan.). A 7 K unigene citrus cDNA microarray containing 12 K spots was used to characterize the transcriptome of the ethylene-induced abscission process in laminar abscission zone-enriched tissues and the petiole of debladed leaf explants. In these conditions, ethylene induced 100% leaf explant abscission in 72 h while, in air-treated samples, the abscission period started later and took 240 h. Gene expression monitored during the first 36 h of ethylene treatment showed that out of the 12 672 cDNA microarray probes, ethylene differentially induced 725 probes distributed as follows: 216 (29.8%) probes in the laminar abscission zone and 509 (70.2%) in the petiole. Functional MIPS classification and manual annotation of differentially expressed genes highlighted key processes regulating the activation and progress of the cell separation that brings about abscission. These included cell-wall modification, lipid transport, protein biosynthesis and degradation, and differential activation of signal transduction and transcription control pathways. Expression data associated with the petiole indicated the occurrence of a double defensive strategy mediated by the activation of a biochemical programme including scavenging ROS, defence and PR genes, and a physical response mostly based on lignin biosynthesis and deposition. This work identifies new genes probably involved in the onset and development of the leaf abscission process and suggests a different but co-ordinated and complementary role for the laminar abscission zone and the petiole during the process of abscission. PMID:18515267

  16. Immunolocalization of pectic polysaccharides during abscission in pea seeds (Pisum sativum L.) and in abscission less def pea mutant seeds.

    PubMed

    Lee, YeonKyeong; Ayeh, Kwadwo Owusu; Ambrose, Mike; Hvoslef-Eide, Anne Kathrine

    2016-08-31

    In pea seeds (Pisum sativum L.), the presence of the Def locus determines abscission event between its funicle and the seed coat. Cell wall remodeling is a necessary condition for abscission of pea seed. The changes in cell wall components in wild type (WT) pea seed with Def loci showing seed abscission and in abscission less def mutant peas were studied to identify the factors determining abscission and non-abscission event. Changes in pectic polysaccharides components were investigated in WT and def mutant pea seeds using immunolabeling techniques. Pectic monoclonal antibodies (1 → 4)-β-D-galactan (LM5), (1 → 5)-α-L-arabinan(LM6), partially de-methyl esterified homogalacturonan (HG) (JIM5) and methyl esterified HG (JIM7) were used for this study. Prior to abscission zone (AZ) development, galactan and arabinan reduced in the predestined AZ of the pea seed and disappeared during the abscission process. The AZ cells had partially de-methyl esterified HG while other areas had highly methyl esterified HG. A strong JIM5 labeling in the def mutant may be related to cell wall rigidity in the mature def mutants. In addition, the appearance of pectic epitopes in two F3 populations resulting from cross between WT and def mutant parents was studied. As a result, we identified that homozygous dominant lines (Def/Def) showing abscission and homozygous recessive lines (def/def) showing non-abscission had similar immunolabeling pattern to their parents. However, the heterogeneous lines (Def/def) showed various immunolabeling pattern and the segregation pattern of the Def locus. Through the study of the complexity and variability of pectins in plant cell walls as well as understanding the segregation patterns of the Def locus using immunolabeling techniques, we conclude that cell wall remodeling occurs in the abscission process and de-methyl esterification may play a role in the non-abscission event in def mutant. Overall, this study contributes new insights into

  17. Regulation of polyamine metabolism and biosynthetic gene expression during olive mature-fruit abscission.

    PubMed

    Gil-Amado, Jose A; Gomez-Jimenez, Maria C

    2012-06-01

    Exogenous ethylene and some inhibitors of polyamine biosynthesis can induce mature-fruit abscission in olive, which could be associated with decreased nitric oxide production as a signaling molecule. Whether H₂O₂ also plays a signaling role in mature-fruit abscission is unknown. The possible involvement of H₂O₂ and polyamine in ethylene-induced mature-fruit abscission was examined in the abscission zone and adjacent cells of two olive cultivars. Endogenous H₂O₂ showed an increase in the abscission zone during mature-fruit abscission, suggesting that accumulated H₂O₂ may participate in abscission signaling. On the other hand, we followed the expression of two genes involved in the polyamine biosynthesis pathway during mature-fruit abscission and in response to ethylene or inhibitors of ethylene and polyamine. OeSAMDC1 and OeSPDS1 were expressed differentially within and between the abscission zones of the two cultivars. OeSAMDC1 showed slightly lower expression in association with mature-fruit abscission. Furthermore, our data show that exogenous ethylene or inhibitors of polyamine encourage the free putrescine pool and decrease the soluble-conjugated spermidine, spermine, homospermidine, and cadaverine in the olive abscission zone, while ethylene inhibition by CoCl₂ increases these soluble conjugates, but does not affect free putrescine. Although the impact of these treatments on polyamine metabolism depends on the cultivar, the results confirm that the mature-fruit abscission may be accompanied by an inhibition of S-adenosyl methionine decarboxylase activity, and the promotion of putrescine synthesis in olive abscission zone, suggesting that endogenous putrescine may play a complementary role to ethylene in the normal course of mature-fruit abscission.

  18. Determination of sugars composition in abscission zone of oil palm fruit

    NASA Astrophysics Data System (ADS)

    Thang, Y. M.; Ariffin, A. A.; Appleton, D. R.; Asis, A. J.; Mokhtar, M. N.; Yunus, R.

    2017-06-01

    Fresh oil palm fruit bunches (FFB) arriving at a palm oil mill are graded manually and randomly for ripeness classification by counting the number of empty fruit sockets (EFS) found in each bunch before processing. FFBs with at least ten EFS are classified as ripe bunch, FFBs with less than ten EFS are classified as under-ripe, while bunches without any EFS are classified as unripe. The aim of the present study is to determine the composition of sugars in the abscission of these three groups of FFBs by monitoring their sugars composition. The bunches were grouped according to the number of empty fruit sockets: (i) nil; (ii) 1-9; (iii) ≥10 as unripe, under-ripe and ripe bunches, respectively. Non-structural, structural and water-soluble sugars extracted from the abscission zone were analyzed. The principal component analysis (PCA) based on various sugars compositions revealed some natural clustering among the samples. Bunches with more than one empty fruit sockets were distinguished from the others using glucose, sucrose and oligomers. In conclusion, analysis of sugars composition of the abscission zone could potentially be used as a chemical marker to differentiate those bunches at different stages of ripeness.

  19. Distribution of XTH, expansin, and secondary-wall-related CesA in floral and fruit abscission zones during fruit development in tomato (Solanum lycopersicum)

    PubMed Central

    Tsuchiya, Mutsumi; Satoh, Shinobu; Iwai, Hiroaki

    2015-01-01

    After fruit development is triggered by pollination, the abscission zone (AZ) in the fruit pedicel strengthens its adhesion to keep the fruit attached. We previously reported that xyloglucan and arabinan accumulation in the AZ accompanies the shedding of unpollinated flowers. After the fruit has developed and is fully ripened, shedding occurs easily in the AZ due to lignin accumulation. Regulation of cell wall metabolism may play an important role in these processes, but it is not well understood. In the present report, we used immunohistochemistry to visualize changes in the distributions of xyloglucan and arabinan metabolism-related enzymes in the AZs of pollinated and unpollinated flowers, and in ripened fruits. During floral abscission, we observed a gradual increase in polyclonal antibody labeling of expansin in the AZ. The intensities of LM6 and LM15 labeling of arabinan and xyloglucan, respectively, also increased. However, during floral abscission, we observed a large 1 day post anthesis (DPA) peak in the polyclonal antibody labeling of XTH in the AZ, which then decreased. These results suggest that expansin and XTH play important, but different roles in the floral abscission process. During fruit abscission, unlike during floral abscission, no AZ-specific expansin and XTH were observed. Although lignification was seen in the AZ of over-ripe fruit pedicels, secondary cell wall-specific cellulose synthase signals were not observed. This suggests that cellulose metabolism-related enzymes do not play important roles in the AZ prior to fruit abscission. PMID:26029225

  20. The influence of abscisic acid on the ethylene biosynthesis pathway in the functioning of the flower abscission zone in Lupinus luteus.

    PubMed

    Wilmowicz, Emilia; Frankowski, Kamil; Kućko, Agata; Świdziński, Michał; de Dios Alché, Juan; Nowakowska, Anna; Kopcewicz, Jan

    2016-11-01

    Flower abscission is a highly regulated developmental process activated in response to exogenous (e.g. changing environmental conditions) and endogenous stimuli (e.g. phytohormones). Ethylene (ET) and abscisic acid (ABA) are very effective stimulators of flower abortion in Lupinus luteus, which is a widely cultivated species in Poland, Australia and Mediterranean countries. In this paper, we show that artificial activation of abscission by flower removal caused an accumulation of ABA in the abscission zone (AZ). Moreover, the blocking of that phytohormone's biosynthesis by NDGA (nordihydroguaiaretic acid) decreased the number of abscised flowers. However, the application of NBD - an inhibitor of ET action - reversed the stimulatory effect of ABA on flower abscission, indicating that ABA itself is not sufficient to turn on the organ separation. Our analysis revealed that exogenous ABA significantly accelerated the transcriptional activity of the ET biosynthesis genes ACC synthase (LlACS) and oxidase (LlACO), and moreover, strongly increased the level of 1-aminocyclopropane-1-carboxylic acid (ACC) - ET precursor, which was specifically localized within AZ cells. We cannot exclude the possibility that ABA mediates flower abscission processes by enhancing the ET biosynthesis rate. The findings of our study will contribute to the overall basic knowledge on the phytohormone-regulated generative organs abscission in L. luteus. Copyright © 2016 Elsevier GmbH. All rights reserved.

  1. A Novel Approach to Dissect the Abscission Process in Arabidopsis1[C][W][OA

    PubMed Central

    González-Carranza, Zinnia Haydee; Shahid, Ahmad Ali; Zhang, Li; Liu, Yang; Ninsuwan, Unchalee; Roberts, Jeremy Alan

    2012-01-01

    Abscission is the consequence of a specialized layer of cells undergoing a complex series of molecular and biochemical events. Analysis of the specific molecular changes associated with abscission is hampered by contamination from neighboring nonseparating tissues. Moreover, studies of abscission frequently involve the examination of events that take place in isolated segments of tissue exposed to nonphysiological concentrations of ethylene or indole-3-acetic acid for protracted periods (more than 24 h) of time. To resolve these problems, we have adopted the use of a transgenic line of Arabidopsis (Arabidopsis thaliana) where the promoter of an abscission-specific polygalacturonase gene (At2g41850/ARABIDOPSIS DEHISCENCE ZONE POLYGALACTURONASE2) has been fused to a green fluorescent protein reporter. RNA was extracted from green fluorescent protein-tagged cells, released from abscising floral organs, and used to generate a complementary DNA library. This library was used to probe a microarray, and a population of abscission-related transcripts was studied in detail. Seven novel abscission-related genes were identified, four of which encode proteins of unknown function. Reverse transcription-polymerase chain reaction analyses and promoter fusions to the β-glucuronidase reporter gene confirmed the expression of these genes in the abscission zone and revealed other places of expression during seedling development. Three of these genes were studied further by crossing reporter lines to the abscission mutants inflorescence deficient in abscission (ida) and blade-on-petiole1 (bop1)/bop2 and an IDA-overexpressing line. Phenotypic analysis of an At3g14380 transfer DNA insertion line indicates that this gene plays a functional role in floral organ shedding. This strategy has enabled us to uncover new genes involved in abscission, and their possible contribution to the process is discussed. PMID:22992509

  2. ALIX and ESCRT-III Coordinately Control Cytokinetic Abscission during Germline Stem Cell Division In Vivo

    PubMed Central

    Eikenes, Åsmund H.; Malerød, Lene; Christensen, Anette Lie; Steen, Chloé B.; Mathieu, Juliette; Nezis, Ioannis P.; Liestøl, Knut; Huynh, Jean-René; Stenmark, Harald; Haglund, Kaisa

    2015-01-01

    Abscission is the final step of cytokinesis that involves the cleavage of the intercellular bridge connecting the two daughter cells. Recent studies have given novel insight into the spatiotemporal regulation and molecular mechanisms controlling abscission in cultured yeast and human cells. The mechanisms of abscission in living metazoan tissues are however not well understood. Here we show that ALIX and the ESCRT-III component Shrub are required for completion of abscission during Drosophila female germline stem cell (fGSC) division. Loss of ALIX or Shrub function in fGSCs leads to delayed abscission and the consequent formation of stem cysts in which chains of daughter cells remain interconnected to the fGSC via midbody rings and fusome. We demonstrate that ALIX and Shrub interact and that they co-localize at midbody rings and midbodies during cytokinetic abscission in fGSCs. Mechanistically, we show that the direct interaction between ALIX and Shrub is required to ensure cytokinesis completion with normal kinetics in fGSCs. We conclude that ALIX and ESCRT-III coordinately control abscission in Drosophila fGSCs and that their complex formation is required for accurate abscission timing in GSCs in vivo. PMID:25635693

  3. Burst of reactive oxygen species in pedicel-mediated fruit abscission after carbohydrate supply was cut off in longan (Dimocarpus longan)

    PubMed Central

    Yang, Ziqin; Zhong, Xiumei; Fan, Yan; Wang, Huicong; Li, Jianguo; Huang, Xuming

    2015-01-01

    Cutting off carbohydrate supply to longan (Dimocarpus longan Lour.) fruit by girdling and defoliation or by detachment induced 100% abscission within a few days. We used these treatments to study the involvement of reactive oxygen species (ROS) in fruit abscission. Girdling plus defoliation decreased sugar concentrations in the fruit and pedicel and depleted starch grains in the chloroplasts in the cells of abscission zone. Prior to the occurrence of intensive fruit abscission, there was a burst in ROS in the pedicel, which peaked at 1 day after treatment (DAT), when H2O2 in the abscission zone was found to be chiefly located along the plasma membrane (PM). H2O2 was found exclusively in the cell walls 2 DAT, almost disappeared 3 DAT, and reappeared in the mitochondria and cell walls 4 DAT. Signs of cell death such as cytoplasm breakdown were apparent from 3 DAT. The burst of ROS coincided with a sharp increase in the activity of PM-bound NADPH oxidase in the pedicel. At the same time, activities of antioxidant enzymes including superoxide dismutase (SOD), catalase, and peroxidase (POD) were all increased by the treatment and maintained higher than those in the control. Accompanying the reduction in H2O2 abundance, there was a sharp decrease in PM-bound NADPH oxidase activity after 1 DAT in the treated fruit. H2O2 scavenger dimethylthiourea (DMTU, 1 g L–1) significantly inhibited fruit abscission in detached fruit clusters and suppressed the increase in cellulase activity in the abscission zone. These results suggest that fruit abscission induced by carbohydrate stress is mediated by ROS. Roles of ROS in regulating fruit abscission were discussed in relation to its subcellular distribution. PMID:26074931

  4. Abscission: The Phytogerontological Effects of Ethylene

    PubMed Central

    Abeles, F. B.; Craker, L. E.; Leather, G. R.

    1971-01-01

    The role of ethylene in the aging of bean (Phaseolus vulgaris L. cv. Red Kidney) petiole abscission zone explants was examined. The data indicate that ethylene does accelerate aging in addition to inducing changes in break strength. Application of ethylene during the aging stage (stage 1) promoted abscission when followed by a second ethylene treatment during the cell separating stage (stage 2). The half-maximal effective concentration of ethylene to induce aging was around 0.3 microliter per liter; 10 microliters per liter was a saturating dose. CO2 reversal of ethylene action during stage 1 was incomplete and gave ambiguous results. CO2 (10%) reversed the effect of 10 microliters per liter ethylene but not 1 microliter per liter ethylene. The possibility that ethylene not only accelerated aging but was also a requirement for it was tested, and experimental evidence in favor of this idea was obtained. It was concluded that ethylene plays a dual role in the abscission of bean petiole explants: a phytogerontological effect and a cellulase-inducing effect. PMID:16657581

  5. Identification of defense-related genes newly-associated with tomato flower abscission

    USDA-ARS?s Scientific Manuscript database

    The current abscission model suggests the formation of a post-abscission trans-differentiation of a protective layer as the last step of the process. The present report expands the repertoire of genes activated in the tomato flower abscission zone (AZ), which are likely to be involved in defense res...

  6. Enhancement of RNA Synthesis, Protein Synthesis, and Abscission by Ethylene

    PubMed Central

    Abeles, F. B.; Holm, R. E.

    1966-01-01

    Ethylene stimulated RNA and protein synthesis in bean (Phaseolus vulgaris L. var. Red Kidney) abscission zone explants prior to abscission. The effect of ethylene on RNA synthesis and abscission was blocked by actinomycin D. Carbon dioxide, which inhibits the effect of ethylene on abscission, also inhibited the influence of ethylene on protein synthesis. An aging period appears to be essential before bean explants respond to ethylene. Stimulation of protein synthesis by ethylene occurred only in receptive or senescent explants. Treatment of juvenile explants with ethylene, which has no effect on abscission also has no effect on protein synthesis. Evidence in favor of a hormonal role for ethylene during abscission is discussed. PMID:16656405

  7. Abscission zone development in Setaria viridis and its domesticated relative, Setaria italica.

    PubMed

    Hodge, John G; Kellogg, Elizabeth A

    2016-06-01

    Development of an abscission zone (AZ) is needed for dispersal of seeds, and AZ loss was a critical early step in plant domestication. The AZ forms in different tissues in different species of plants, but whether the AZ is developmentally similar wherever it occurs is unknown. AZ development in Setaria viridis was studied as a representative of the previously uncharacterized subfamily Panicoideae. One accession of the wild species S. viridis and two of its domesticate, S. italica, were studied. Strength of the AZ was measured with a force gauge. Anatomy of the AZ was studied throughout development using bright field and confocal microscopy. The force required to remove a spikelet of S. viridis from the parent plant dropped steadily during development, whereas that required to remove spikelets of S. italica increased initially before stabilizing at a high level. Despite the clear difference in tensile strength of the AZ, anatomical differences between S. viridis and S. italica were subtle, and the position of the AZ was not easy to determine in cross sections of pedicel apices. Staining with DAPI showed that nuclei were present up to and presumably through abscission in S. viridis, and acridine orange staining showed much less lignification than in other cereals. The AZ in Setaria is developmentally and anatomically different from that characterized in rice, barley, and many eudicots. In particular, no set of small, densely cytoplasmic cells is obvious. This difference in anatomy could point to differential genetic control of the structure. © 2016 Botanical Society of America.

  8. Transcriptome profiling of petal abscission zone and functional analysis of AUX/IAA family genes reveal that RhIAA16 is involved in petal shedding in rose

    USDA-ARS?s Scientific Manuscript database

    Rose is one of the most important cut flowers among ornamental plants. Rose flower longevity is largely dependent on the timing of petal shedding occurrence. To understand the molecular mechanism underlying petal abscission in rose, we performed transcriptome profiling of the petal abscission zone d...

  9. Cellular and Pectin Dynamics during Abscission Zone Development and Ripe Fruit Abscission of the Monocot Oil Palm

    PubMed Central

    Roongsattham, Peerapat; Morcillo, Fabienne; Fooyontphanich, Kim; Jantasuriyarat, Chatchawan; Tragoonrung, Somvong; Amblard, Philippe; Collin, Myriam; Mouille, Gregory; Verdeil, Jean-Luc; Tranbarger, Timothy J.

    2016-01-01

    The oil palm (Elaeis guineensis Jacq.) fruit primary abscission zone (AZ) is a multi-cell layered boundary region between the pedicel (P) and mesocarp (M) tissues. To examine the cellular processes that occur during the development and function of the AZ cell layers, we employed multiple histological and immunohistochemical methods combined with confocal, electron and Fourier-transform infrared (FT-IR) microspectroscopy approaches. During early fruit development and differentiation of the AZ, the orientation of cell divisions in the AZ was periclinal compared with anticlinal divisions in the P and M. AZ cell wall width increased earlier during development suggesting cell wall assembly occurred more rapidly in the AZ than the adjacent P and M tissues. The developing fruit AZ contain numerous intra-AZ cell layer plasmodesmata (PD), but very few inter-AZ cell layer PD. In the AZ of ripening fruit, PD were less frequent, wider, and mainly intra-AZ cell layer localized. Furthermore, DAPI staining revealed nuclei are located adjacent to PD and are remarkably aligned within AZ layer cells, and remain aligned and intact after cell separation. The polarized accumulation of ribosomes, rough endoplasmic reticulum, mitochondria, and vesicles suggested active secretion at the tip of AZ cells occurred during development which may contribute to the striated cell wall patterns in the AZ cell layers. AZ cells accumulated intracellular pectin during development, which appear to be released and/or degraded during cell separation. The signal for the JIM5 epitope, that recognizes low methylesterified and un-methylesterified homogalacturonan (HG), increased in the AZ layer cell walls prior to separation and dramatically increased on the separated AZ cell surfaces. Finally, FT-IR microspectroscopy analysis indicated a decrease in methylesterified HG occurred in AZ cell walls during separation, which may partially explain an increase in the JIM5 epitope signal. The results obtained

  10. Localization of Sphingolipid Enriched Plasma Membrane Regions and Long-Chain Base Composition during Mature-Fruit Abscission in Olive.

    PubMed

    Parra-Lobato, Maria C; Paredes, Miguel A; Labrador, Juana; Saucedo-García, Mariana; Gavilanes-Ruiz, Marina; Gomez-Jimenez, Maria C

    2017-01-01

    Sphingolipids, found in membranes of eukaryotic cells, have been demonstrated to carry out functions in various processes in plant cells. However, the roles of these lipids in fruit abscission remain to be determined in plants. Biochemical and fluorescence microscopy imaging approach has been adopted to investigate the accumulation and distribution of sphingolipids during mature-fruit abscission in olive ( Olea europaea L. cv. Picual). Here, a lipid-content analysis in live protoplasts of the olive abscission zone (AZ) was made with fluorescent dyes and lipid analogs, particularly plasma membrane sphingolipid-enriched domains, and their dynamics were investigated in relation to the timing of mature-fruit abscission. In olive AZ cells, the measured proportion of both polar lipids and sphingolipids increased as well as endocytosis was stimulated during mature-fruit abscission. Likewise, mature-fruit abscission resulted in quantitative and qualitative changes in sphingolipid long-chain bases (LCBs) in the olive AZ. The total LCB increase was due essentially to the increase of t18:1(8 E ) LCBs, suggesting that C-4 hydroxylation and Δ8 desaturation with a preference for ( E )-isomer formation were quantitatively the most important sphingolipids in olive AZ during abscission. However, our results also showed a specific association between the dihydroxylated LCB sphinganine (d18:0) and the mature-fruit abscission. These results indicate a clear correlation between the sphingolipid composition and mature-fruit abscission. Moreover, measurements of endogenous sterol levels in the olive AZ revealed that it accumulated sitosterol and campesterol with a concomitant decrease in cycloartenol during abscission. In addition, underlying the distinct sterol composition of AZ during abscission, genes for key biosynthetic enzymes for sterol synthesis, for obtusifoliol 14α-demethylase (CYP51) and C-24 sterol methyltransferase2 (SMT2), were up-regulated during mature-fruit abscission

  11. Localization of Sphingolipid Enriched Plasma Membrane Regions and Long-Chain Base Composition during Mature-Fruit Abscission in Olive

    PubMed Central

    Parra-Lobato, Maria C.; Paredes, Miguel A.; Labrador, Juana; Saucedo-García, Mariana; Gavilanes-Ruiz, Marina; Gomez-Jimenez, Maria C.

    2017-01-01

    Sphingolipids, found in membranes of eukaryotic cells, have been demonstrated to carry out functions in various processes in plant cells. However, the roles of these lipids in fruit abscission remain to be determined in plants. Biochemical and fluorescence microscopy imaging approach has been adopted to investigate the accumulation and distribution of sphingolipids during mature-fruit abscission in olive (Olea europaea L. cv. Picual). Here, a lipid-content analysis in live protoplasts of the olive abscission zone (AZ) was made with fluorescent dyes and lipid analogs, particularly plasma membrane sphingolipid-enriched domains, and their dynamics were investigated in relation to the timing of mature-fruit abscission. In olive AZ cells, the measured proportion of both polar lipids and sphingolipids increased as well as endocytosis was stimulated during mature-fruit abscission. Likewise, mature-fruit abscission resulted in quantitative and qualitative changes in sphingolipid long-chain bases (LCBs) in the olive AZ. The total LCB increase was due essentially to the increase of t18:1(8E) LCBs, suggesting that C-4 hydroxylation and Δ8 desaturation with a preference for (E)-isomer formation were quantitatively the most important sphingolipids in olive AZ during abscission. However, our results also showed a specific association between the dihydroxylated LCB sphinganine (d18:0) and the mature-fruit abscission. These results indicate a clear correlation between the sphingolipid composition and mature-fruit abscission. Moreover, measurements of endogenous sterol levels in the olive AZ revealed that it accumulated sitosterol and campesterol with a concomitant decrease in cycloartenol during abscission. In addition, underlying the distinct sterol composition of AZ during abscission, genes for key biosynthetic enzymes for sterol synthesis, for obtusifoliol 14α-demethylase (CYP51) and C-24 sterol methyltransferase2 (SMT2), were up-regulated during mature-fruit abscission, in

  12. Ethylene-responsive genes are differentially regulated during abscission, organ senescence and wounding in peach (Prunus persica).

    PubMed

    Ruperti, Benedetto; Cattivelli, Luigi; Pagni, Silvana; Ramina, Angelo

    2002-03-01

    Ethylene-responsive genes from peach (Prunus persica, L. Batsch) were isolated by differential screening of a cDNA library constructed from abscission zones in which cell separation had been evoked by treatment with the ethylene analogue propylene. DNA and deduced protein sequences of four selected clones, termed Prunus persica Abscission zone (PpAz), revealed homology to thaumatin-like proteins (PpAz8 and PpAz44), to proteins belonging to the PR4 class of pathogenesis-related (PR) proteins (PpAz89), and to fungal and plant beta-D-xylosidases (PpAz152). Expression analyses conducted on embrioctomized and CEPA-treated fruitlets as well as on fruit explants have shown that PpAz8, PpAz44 and PpAz89 are preferentially transcribed in the cells of the fruit abscission zone rather than in the non-zone tissues. The PpAz152 transcript showed a different accumulation pattern being consistently and promptly induced by wounding and only slightly stimulated by propylene. By contrast, a complex pattern of transcript accumulation was found for the four genes in response to the wounding of leaves and during organ development and senescence. Based on this evidence, the existence of multiple regulatory pathways underlying the differential expression of the four PpAz genes in the different tissues and physiological processes is hypothesized.

  13. A beta-galactosidase gene is expressed during mature fruit abscission of 'Valencia' orange (Citrus sinensis).

    PubMed

    Wu, Zhencai; Burns, Jacqueline K

    2004-07-01

    beta-galactosidases have been detected in a wide range of plants and are characterized by their ability to hydrolyse terminal non-reducing beta-D-galactosyl residues from beta-D-galactosides. These enzymes have been detected in a wide range of plant organs and tissues. In a search for differentially expressed genes during the abscission process in citrus, sequences encoding beta-galactosidase were identified. Three cDNA fragments of a beta-galactosidase gene were isolated from a cDNA subtraction library constructed from mature fruit abscission zones 48 h after the application of a mature fruit-specific abscission agent, 5-chloro-3-methyl-4-nitro-1H-pyrazole (CMN-pyrazole). Based on sequence information derived from these fragments, a full-length cDNA of 2847 nucleotides (GenBank accession number AY029198) encoding beta-galactosidase was isolated from mature fruit abscission zones by 5'- and 3'-RACE approaches. The beta-galactosidase cDNA encoded a protein of 737 amino acid residues with a calculated molecular weight of 82 kDa. The deduced protein was highly homologous to plant beta-galactosidases expressed in fruit ripening. Southern blot analysis demonstrated that at least two closely related beta-galactosidase genes were present in 'Valencia' orange. Temporal expression patterns in mature fruit abscission zones indicated beta-galactosidase mRNA was detected 48 h after treatment of CMN-pyrazole and ethephon in mature fruit abscission zones. beta-galactosidase transcripts were detected in leaf abscission zones only after ethephon application. The citrus beta-galactosidase was expressed in stamens and petals of fully opened flowers and young fruitlets. The results suggest that this beta-galactosidase may play a role during abscission as well as early growth and development processes in flowers and fruitlets.

  14. De novo transcriptome sequencing and customized abscission zone-specific microarray as a new molecular tool for analysis of tomato organ abscission

    USDA-ARS?s Scientific Manuscript database

    Abscission, which is the process of organ separation, is a highly regulated process occurring as a final stage of organ development. In the tomato (Solanum lycopersicum) system, flower and leaf abscission was induced by flower removal or leaf deblading, leading to auxin depletion which results in in...

  15. Identification of defense-related genes newly-associated with tomato flower abscission.

    PubMed

    Meir, Shimon; Philosoph-Hadas, Sonia; Sundaresan, Srivignesh; Selvaraj, K S Vijay; Burd, Shaul; Ophir, Ron; Kochanek, K S Bettina; Reid, Michael S; Jiang, Cai-Zhong; Lers, Amnon

    2011-04-01

    The current abscission model suggests the formation of a post-abscission trans-differentiation of a protective layer as the last step of the process. The present report expands the repertoire of genes activated in the tomato flower abscission zone (AZ), which are likely to be involved in defense responses. We identified four different defense-related genes, including: Cysteine-type endopeptidase, α-Dioxygenase 1 (α-DOX1), HopW-1-1-Interacting protein2 (WIN2), and Stomatal-derived factor-2 (SDF2), that are newly-associated with the late stage of the abscission process. The late expression of these genes, induced at 8-14 h after flower removal when pedicel abscission was already in progress, was AZ-specific, and was inhibited by treatments that prevented pedicel abscission, including 1-methylcyclopropene pretreatment or IAA application. This information supports the activation of different defense responses and strategies at the late abscission stages, which may enable efficient protection of the exposed tissue toward different environmental stresses.

  16. Genome-wide digital transcript analysis of putative fruitlet abscission related genes regulated by ethephon in litchi

    PubMed Central

    Li, Caiqin; Wang, Yan; Ying, Peiyuan; Ma, Wuqiang; Li, Jianguo

    2015-01-01

    The high level of physiological fruitlet abscission in litchi (Litchi chinensis Sonn.) causes severe yield loss. Cell separation occurs at the fruit abscission zone (FAZ) and can be triggered by ethylene. However, a deep knowledge of the molecular events occurring in the FAZ is still unknown. Here, genome-wide digital transcript abundance (DTA) analysis of putative fruit abscission related genes regulated by ethephon in litchi were studied. More than 81 million high quality reads from seven ethephon treated and untreated control libraries were obtained by high-throughput sequencing. Through DTA profile analysis in combination with Gene Ontology and KEGG pathway enrichment analyses, a total of 2730 statistically significant candidate genes were involved in the ethephon-promoted litchi fruitlet abscission. Of these, there were 1867 early-responsive genes whose expressions were up- or down-regulated from 0 to 1 d after treatment. The most affected genes included those related to ethylene biosynthesis and signaling, auxin transport and signaling, transcription factors (TFs), protein ubiquitination, ROS response, calcium signal transduction, and cell wall modification. These genes could be clustered into four groups and 13 subgroups according to their similar expression patterns. qRT-PCR displayed the expression pattern of 41 selected candidate genes, which proved the accuracy of our DTA data. Ethephon treatment significantly increased fruit abscission and ethylene production of fruitlet. The possible molecular events to control the ethephon-promoted litchi fruitlet abscission were prompted out. The increased ethylene evolution in fruitlet would suppress the synthesis and polar transport of auxin and trigger abscission signaling. To the best of our knowledge, it is the first time to monitor the gene expression profile occurring in the FAZ-enriched pedicel during litchi fruit abscission induced by ethephon on the genome-wide level. This study will contribute to a better

  17. Examination of the Abscission-Associated Transcriptomes for Soybean, Tomato, and Arabidopsis Highlights the Conserved Biosynthesis of an Extensible Extracellular Matrix and Boundary Layer.

    PubMed

    Kim, Joonyup; Sundaresan, Srivignesh; Philosoph-Hadas, Sonia; Yang, Ronghui; Meir, Shimon; Tucker, Mark L

    2015-01-01

    Abscission zone (AZ) development and the progression of abscission (detachment of plant organs) have been roughly separated into four stages: first, AZ differentiation; second, competence to respond to abscission signals; third, activation of abscission; and fourth, formation of a protective layer and post-abscission trans-differentiation. Stage three, activation of abscission, is when changes in the cell wall and extracellular matrix occur to support successful organ separation. Most abscission research has focused on gene expression for enzymes that disassemble the cell wall within the AZ and changes in phytohormones and other signaling events that regulate their expression. Here, transcriptome data for soybean, tomato and Arabidopsis were examined and compared with a focus not only on genes associated with disassembly of the cell wall but also on gene expression linked to the biosynthesis of a new extracellular matrix. AZ-specific up-regulation of genes associated with cell wall disassembly including cellulases (beta-1,4-endoglucanases, CELs), polygalacturonases (PGs), and expansins (EXPs) were much as expected; however, curiously, changes in expression of xyloglucan endotransglucosylase/hydrolases (XTHs) were not AZ-specific in soybean. Unexpectedly, we identified an early increase in the expression of genes underlying the synthesis of a waxy-like cuticle. Based on the expression data, we propose that the early up-regulation of an abundance of small pathogenesis-related (PR) genes is more closely linked to structural changes in the extracellular matrix of separating cells than an enzymatic role in pathogen resistance. Furthermore, these observations led us to propose that, in addition to cell wall loosening enzymes, abscission requires (or is enhanced by) biosynthesis and secretion of small proteins (15-25 kDa) and waxes that form an extensible extracellular matrix and boundary layer on the surface of separating cells. The synthesis of the boundary layer

  18. MOLECULAR ANALYSIS OF THE INTERACTION OF ETHYLENE AND AUXIN DURING FLOWER ABSCISSION

    USDA-ARS?s Scientific Manuscript database

    Abscission, the separation of organs from the parent plant, results in postharvest quality loss in many ornamentals and other fresh produce. The process is initiated by changes in the auxin gradient across the abscission zone (AZ), is triggered by ethylene, and may be accelerated by postharvest stre...

  19. Transcriptional activation of a 37 kDa ethylene responsive cysteine protease gene, RbCP1, is associated with protein degradation during petal abscission in rose

    PubMed Central

    Tripathi, Siddharth Kaushal; Singh, Amar Pal; Sane, Aniruddha P.; Nath, Pravendra

    2009-01-01

    Cysteine proteases play an important role in several developmental processes in plants, particularly those related to senescence and cell death. A cysteine protease gene, RbCP1, has been identified that encodes a putative protein of 357 amino acids and is expressed in the abscission zone (AZ) of petals in rose. The gene was responsive to ethylene in petals, petal abscission zones, leaves, and thalamus. The expression of RbCP1 increased during both ethylene-induced as well as natural abscission and was inhibited by 1-MCP. Transcript accumulation of RbCP1 was accompanied by the appearance of a 37 kDa cysteine protease, a concomitant increase in protease activity and a substantial decrease in total protein content in the AZ of petals. Agro-injection of rose petals with a 2.0 kb region upstream of the RbCP1 gene could drive GUS expression in an abscission zone-specific manner and was blocked by 1-MCP. It is concluded that petal abscission is associated with a decrease in total protein content resulting from rapid transcription of RbCP1 and the expression of a 37 kDa protease. PMID:19346241

  20. Isolation and characterization of a cDNA encoding a lipid transfer protein expressed in 'Valencia' orange during abscission.

    PubMed

    Wu, Zhencai; Burns, Jacqueline K

    2003-04-01

    The genetics and expression of a lipid transfer protein (LTP) gene was examined during abscission of mature fruit of 'Valencia' orange. A cDNA encoding an LTP, CsLTP, was isolated from a cDNA subtraction library constructed from mature fruit abscission zones 48 h after application of a mature fruit-specific abscission agent, 5-chloro-3-methyl-4-nitro-pyrazole (CMN-pyrazole). A full-length cDNA clone of 652 nucleotides was isolated using 5' and 3' RACE followed by cDNA library screening and PCR amplification. The cDNA clone encoded a protein of 155 amino acid residues with a molecular mass and isoelectric point of 9.18 kDa and 9.12, respectively. A partial genomic clone of 505 nucleotides containing one intron of 101 base pairs was amplified from leaf genomic DNA. Southern blot hybridization demonstrated that at least two closely related CsLTP genes are present in 'Valencia' orange. Temporal expression patterns in mature fruit abscission zones were examined by northern hybridization. Increased expression of CsLTP mRNA was detected in RNA of mature fruit abscission zones 6, 24, 48, and 72 h after application of a non-specific abscission agent, ethephon. Low expression of CsLTP transcripts was observed after treatment of CMN-pyrazole until 24 h after application. After this time, expression markedly increased. The results suggest that CsLTP has a role in the abscission process, possibly by assisting transport of cutin monomers to the fracture plane of the abscission zone or through its anti-microbial activity by reducing the potential of microbial attack.

  1. Overexpression of a novel MADS-box gene SlFYFL delays senescence, fruit ripening and abscission in tomato

    PubMed Central

    Xie, Qiaoli; Hu, Zongli; Zhu, Zhiguo; Dong, Tingting; Zhao, Zhiping; Cui, Baolu; Chen, Guoping

    2014-01-01

    MADS-domain proteins are important transcription factors involved in many biological processes of plants. In our study, a tomato MADS-box gene, SlFYFL, was isolated. SlFYFL is expressed in all tissues of tomato and significantly higher in mature leave, fruit of different stages, AZ (abscission zone) and sepal. Delayed leaf senescence and fruit ripening, increased storability and longer sepals were observed in 35S:FYFL tomato. The accumulation of carotenoid was reduced, and ethylene content, ethylene biosynthetic and responsive genes were down-regulated in 35S:FYFL fruits. Abscission zone (AZ) did not form normally and abscission zone development related genes were declined in AZs of 35S:FYFL plants. Yeast two-hybrid assay revealed that SlFYFL protein could interact with SlMADS-RIN, SlMADS1 and SlJOINTLESS, respectively. These results suggest that overexpression of SlFYFL regulate fruit ripening and development of AZ via interactions with the ripening and abscission zone-related MADS box proteins. PMID:24621662

  2. Polyamine-induced modulation of genes involved in ethylene biosynthesis and signalling pathways and nitric oxide production during olive mature fruit abscission

    PubMed Central

    Parra-Lobato, Maria C.; Gomez-Jimenez, Maria C.

    2011-01-01

    After fruit ripening, many fruit-tree species undergo massive natural fruit abscission. Olive (Olea europaea L.) is a stone-fruit with cultivars such as Picual (PIC) and Arbequina (ARB) which differ in mature fruit abscission potential. Ethylene (ET) is associated with abscission, but its role during mature fruit abscission remains largely uncharacterized. The present study investigates the possible roles of ET and polyamine (PA) during mature fruit abscission by modulating genes involved in the ET signalling and biosynthesis pathways in the abscission zone (AZ) of both cultivars. Five ET-related genes (OeACS2, OeACO2, OeCTR1, OeERS1, and OeEIL2) were isolated in the AZ and adjacent cells (AZ–AC), and their expression in various olive organs and during mature fruit abscission, in relation to interactions between ET and PA and the expression induction of these genes, was determined. OeACS2, OeACO2, and OeEIL2 were found to be the only genes that were up-regulated in association with mature fruit abscission. Using the inhibition of ET and PA biosynthesis, it is demonstrated that OeACS2 and OeEIL2 expression are under the negative control of PA while ET induces their expression in AZ–AC. Furthermore, mature fruit abscission depressed nitric oxide (NO) production present mainly in the epidermal cells and xylem of the AZ. Also, NO production was differentially responsive to ET, PA, and different inhibitors. Taken together, the results indicate that PA-dependent ET signalling and biosynthesis pathways participate, at least partially, during mature fruit abscission, and that endogenous NO and 1-aminocyclopropane-1-carboxylic acid maintain an inverse correlation, suggesting an antagonistic action of NO and ET in abscission signalling. PMID:21633085

  3. ULK3 regulates cytokinetic abscission by phosphorylating ESCRT-III proteins

    DOE PAGES

    Caballe, Anna; Wenzel, Dawn M.; Agromayor, Monica; ...

    2015-05-26

    The endosomal sorting complexes required for transport (ESCRT) machinery mediates the physical separation between daughter cells during cytokinetic abscission. This process is regulated by the abscission checkpoint, a genome protection mechanism that relies on Aurora B and the ESCRT-III subunit CHMP4C to delay abscission in response to chromosome missegregation. In this study, we show that Unc-51-like kinase 3 (ULK3) phosphorylates and binds ESCRT-III subunits via tandem MIT domains, and thereby, delays abscission in response to lagging chromosomes, nuclear pore defects, and tension forces at the midbody. Our structural and biochemical studies reveal an unusually tight interaction between ULK3 and IST1,more » an ESCRT-III subunit required for abscission. We also demonstrate that IST1 phosphorylation by ULK3 is an essential signal required to sustain the abscission checkpoint and that ULK3 and CHMP4C are functionally linked components of the timer that controls abscission in multiple physiological situations.« less

  4. ULK3 regulates cytokinetic abscission by phosphorylating ESCRT-III proteins

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

    Caballe, Anna; Wenzel, Dawn M.; Agromayor, Monica

    The endosomal sorting complexes required for transport (ESCRT) machinery mediates the physical separation between daughter cells during cytokinetic abscission. This process is regulated by the abscission checkpoint, a genome protection mechanism that relies on Aurora B and the ESCRT-III subunit CHMP4C to delay abscission in response to chromosome missegregation. In this study, we show that Unc-51-like kinase 3 (ULK3) phosphorylates and binds ESCRT-III subunits via tandem MIT domains, and thereby, delays abscission in response to lagging chromosomes, nuclear pore defects, and tension forces at the midbody. Our structural and biochemical studies reveal an unusually tight interaction between ULK3 and IST1,more » an ESCRT-III subunit required for abscission. We also demonstrate that IST1 phosphorylation by ULK3 is an essential signal required to sustain the abscission checkpoint and that ULK3 and CHMP4C are functionally linked components of the timer that controls abscission in multiple physiological situations.« less

  5. CGGBP1 is a nuclear and midbody protein regulating abscission

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

    Singh, Umashankar, E-mail: umashankar.singh@genpat.uu.se; Westermark, Bengt

    2011-01-15

    Abscission marks the completion of cell division and its failure is associated with delayed cytokinesis and even tetraploidization. Aberrant abscission and consequential ploidy changes can underlie various diseases including cancer. Midbody, a transient structure formed in the intercellular bridge during telophase, contains several proteins including Aurora kinase B (AURKB), which participate in abscission. We report here an unexpected expression pattern and function of the transcription repressor protein CGG triplet repeat-binding protein 1 (CGGBP1), in normal human fibroblasts. We show that CGGBP1, a chromatin-associated protein, trans-localizes to spindle midzone and midbodies in a manner similar to that of AURKB. CGGBP1 depletionmore » resulted in a cell cycle block at G2, characterized by failure of cells to undergo mitosis and also reduced entry into S phase. Consistent with its presence in the midbodies, live microscopy showed that CGGBP1 deficiency caused mitotic failure at abscission resulting in tetraploidy, which could be rescued by CGGBP1 overexpression. These results show that CGGBP1 is a bona fide midbody protein required for normal abscission and mitosis in general.« less

  6. ULK3 regulates cytokinetic abscission by phosphorylating ESCRT-III proteins

    PubMed Central

    Caballe, Anna; Wenzel, Dawn M; Agromayor, Monica; Alam, Steven L; Skalicky, Jack J; Kloc, Magdalena; Carlton, Jeremy G; Labrador, Leticia; Sundquist, Wesley I; Martin-Serrano, Juan

    2015-01-01

    The endosomal sorting complexes required for transport (ESCRT) machinery mediates the physical separation between daughter cells during cytokinetic abscission. This process is regulated by the abscission checkpoint, a genome protection mechanism that relies on Aurora B and the ESCRT-III subunit CHMP4C to delay abscission in response to chromosome missegregation. In this study, we show that Unc-51-like kinase 3 (ULK3) phosphorylates and binds ESCRT-III subunits via tandem MIT domains, and thereby, delays abscission in response to lagging chromosomes, nuclear pore defects, and tension forces at the midbody. Our structural and biochemical studies reveal an unusually tight interaction between ULK3 and IST1, an ESCRT-III subunit required for abscission. We also demonstrate that IST1 phosphorylation by ULK3 is an essential signal required to sustain the abscission checkpoint and that ULK3 and CHMP4C are functionally linked components of the timer that controls abscission in multiple physiological situations. DOI: http://dx.doi.org/10.7554/eLife.06547.001 PMID:26011858

  7. ARABIDOPSIS DEHISCENCE ZONE POLYGALACTURONASE1 (ADPG1), ADPG2, and QUARTET2 Are Polygalacturonases Required for Cell Separation during Reproductive Development in Arabidopsis[W

    PubMed Central

    Ogawa, Mikihiro; Kay, Pippa; Wilson, Sarah; Swain, Stephen M.

    2009-01-01

    Cell separation is thought to involve degradation of pectin by several hydrolytic enzymes, particularly polygalacturonase (PG). Here, we characterize an activation tagging line with reduced growth and male sterility caused by increased expression of a PG encoded by QUARTET2 (QRT2). QRT2 is essential for pollen grain separation and is part of a small family of three closely related endo-PGs in the Arabidopsis thaliana proteome, including ARABIDOPSIS DEHISCENCE ZONE POLYGALACTURONASE1 (ADPG1) and ADPG2. Functional assays and complementation experiments confirm that ADPG1, ADPG2, and QRT2 are PGs. Genetic analysis demonstrates that ADPG1 and ADPG2 are essential for silique dehiscence. In addition, ADPG2 and QRT2 contribute to floral organ abscission, while all three genes contribute to anther dehiscence. Expression analysis is consistent with the observed mutant phenotypes. INDEHISCENT (IND) encodes a putative basic helix-loop-helix required for silique dehiscence, and we demonstrate that the closely related HECATE3 (HEC3) gene is required for normal seed abscission and show that IND and HEC3 are required for normal expression of ADPG1 in the silique dehiscence zone and seed abscission zone, respectively. We also show that jasmonic acid and ethylene act together with abscisic acid to regulate floral organ abscission, in part by promoting QRT2 expression. These results demonstrate that multiple cell separation events, including both abscission and dehiscence, require closely related PG genes. PMID:19168715

  8. De novo Transcriptome Profiling of Flowers, Flower Pedicels and Pods of Lupinus luteus (Yellow Lupine) Reveals Complex Expression Changes during Organ Abscission.

    PubMed

    Glazinska, Paulina; Wojciechowski, Waldemar; Kulasek, Milena; Glinkowski, Wojciech; Marciniak, Katarzyna; Klajn, Natalia; Kesy, Jacek; Kopcewicz, Jan

    2017-01-01

    Yellow lupine ( Lupinus luteus L., Taper c.), a member of the legume family ( Fabaceae L.), has an enormous practical importance. Its excessive flower and pod abscission represents an economic drawback, as proper flower and seed formation and development is crucial for the plant's productivity. Generative organ detachment takes place at the basis of the pedicels, within a specialized group of cells collectively known as the abscission zone (AZ). During plant growth these cells become competent to respond to specific signals that trigger separation and lead to the abolition of cell wall adhesion. Little is known about the molecular network controlling the yellow lupine organ abscission. The aim of our study was to establish the divergences and similarities in transcriptional networks in the pods, flowers and flower pedicels abscised or maintained on the plant, and to identify genes playing key roles in generative organ abscission in yellow lupine. Based on de novo transcriptome assembly, we identified 166,473 unigenes representing 219,514 assembled unique transcripts from flowers, flower pedicels and pods undergoing abscission and from control organs. Comparison of the cDNA libraries from dropped and control organs helped in identifying 1,343, 2,933 and 1,491 differentially expressed genes (DEGs) in the flowers, flower pedicels and pods, respectively. In DEG analyses, we focused on genes involved in phytohormonal regulation, cell wall functioning and metabolic pathways. Our results indicate that auxin, ethylene and gibberellins are some of the main factors engaged in generative organ abscission. Identified 28 DEGs common for all library comparisons are involved in cell wall functioning, protein metabolism, water homeostasis and stress response. Interestingly, among the common DEGs we also found an miR169 precursor, which is the first evidence of micro RNA engaged in abscission. A KEGG pathway enrichment analysis revealed that the identified DEGs were predominantly

  9. De novo Transcriptome Profiling of Flowers, Flower Pedicels and Pods of Lupinus luteus (Yellow Lupine) Reveals Complex Expression Changes during Organ Abscission

    PubMed Central

    Glazinska, Paulina; Wojciechowski, Waldemar; Kulasek, Milena; Glinkowski, Wojciech; Marciniak, Katarzyna; Klajn, Natalia; Kesy, Jacek; Kopcewicz, Jan

    2017-01-01

    Yellow lupine (Lupinus luteus L., Taper c.), a member of the legume family (Fabaceae L.), has an enormous practical importance. Its excessive flower and pod abscission represents an economic drawback, as proper flower and seed formation and development is crucial for the plant's productivity. Generative organ detachment takes place at the basis of the pedicels, within a specialized group of cells collectively known as the abscission zone (AZ). During plant growth these cells become competent to respond to specific signals that trigger separation and lead to the abolition of cell wall adhesion. Little is known about the molecular network controlling the yellow lupine organ abscission. The aim of our study was to establish the divergences and similarities in transcriptional networks in the pods, flowers and flower pedicels abscised or maintained on the plant, and to identify genes playing key roles in generative organ abscission in yellow lupine. Based on de novo transcriptome assembly, we identified 166,473 unigenes representing 219,514 assembled unique transcripts from flowers, flower pedicels and pods undergoing abscission and from control organs. Comparison of the cDNA libraries from dropped and control organs helped in identifying 1,343, 2,933 and 1,491 differentially expressed genes (DEGs) in the flowers, flower pedicels and pods, respectively. In DEG analyses, we focused on genes involved in phytohormonal regulation, cell wall functioning and metabolic pathways. Our results indicate that auxin, ethylene and gibberellins are some of the main factors engaged in generative organ abscission. Identified 28 DEGs common for all library comparisons are involved in cell wall functioning, protein metabolism, water homeostasis and stress response. Interestingly, among the common DEGs we also found an miR169 precursor, which is the first evidence of micro RNA engaged in abscission. A KEGG pathway enrichment analysis revealed that the identified DEGs were predominantly

  10. Primary and Secondary Abscission in Pisum sativum and Euphorbia pulcherrima—How Do They Compare and How Do They Differ?

    PubMed Central

    Hvoslef-Eide, Anne K.; Munster, Cristel M.; Mathiesen, Cecilie A.; Ayeh, Kwadwo O.; Melby, Tone I.; Rasolomanana, Paoly; Lee, YeonKyeong

    2016-01-01

    Abscission is a highly regulated and coordinated developmental process in plants. It is important to understand the processes leading up to the event, in order to better control abscission in crop plants. This has the potential to reduce yield losses in the field and increase the ornamental value of flowers and potted plants. A reliable method of abscission induction in poinsettia (Euphorbia pulcherrima) flowers has been established to study the process in a comprehensive manner. By correctly decapitating buds of the third order, abscission can be induced in 1 week. AFLP differential display (DD) was used to search for genes regulating abscission. Through validation using qRT-PCR, more information of the genes involved during induced secondary abscission have been obtained. A study using two pea (Pisum sativum) mutants in the def (Developmental funiculus) gene, which was compared with wild type peas (tall and dwarf in both cases) was performed. The def mutant results in a deformed, abscission-less zone instead of normal primary abscission at the funiculus. RNA in situ hybridization studies using gene sequences from the poinsettia differential display, resulted in six genes differentially expressed for abscission specific genes in both poinsettia and pea. Two of these genes are associated with gene up- or down-regulation during the first 2 days after decapitation in poinsettia. Present and previous results in poinsettia (biochemically and gene expressions), enables a more detailed division of the secondary abscission phases in poinsettia than what has previously been described from primary abscission in Arabidopsis. This study compares the inducible secondary abscission in poinsettia and the non-abscising mutants/wild types in pea demonstrating primary abscission zones. The results may have wide implications on the understanding of abscission, since pea and poinsettia have been separated for 94–98 million years in evolution, hence any genes or processes in common

  11. The midbody ring scaffolds the abscission machinery in the absence of midbody microtubules

    PubMed Central

    Green, Rebecca A.; Mayers, Jonathan R.; Wang, Shaohe; Lewellyn, Lindsay; Desai, Arshad; Audhya, Anjon

    2013-01-01

    Abscission completes cytokinesis to form the two daughter cells. Although abscission could be organized from the inside out by the microtubule-based midbody or from the outside in by the contractile ring–derived midbody ring, it is assumed that midbody microtubules scaffold the abscission machinery. In this paper, we assess the contribution of midbody microtubules versus the midbody ring in the Caenorhabditis elegans embryo. We show that abscission occurs in two stages. First, the cytoplasm in the daughter cells becomes isolated, coincident with formation of the intercellular bridge; proper progression through this stage required the septins (a midbody ring component) but not the membrane-remodeling endosomal sorting complex required for transport (ESCRT) machinery. Second, the midbody and midbody ring are released into a specific daughter cell during the subsequent cell division; this stage required the septins and the ESCRT machinery. Surprisingly, midbody microtubules were dispensable for both stages. These results delineate distinct steps during abscission and highlight the central role of the midbody ring, rather than midbody microtubules, in their execution. PMID:24217623

  12. Ethephon induced abscission in mango: physiological fruitlet responses

    PubMed Central

    Hagemann, Michael H.; Winterhagen, Patrick; Hegele, Martin; Wünsche, Jens N.

    2015-01-01

    Fruitlet abscission of mango is typically very severe, causing considerable production losses worldwide. Consequently, a detailed physiological and molecular characterization of fruitlet abscission in mango is required to describe the onset and time-dependent course of this process. To identify the underlying key mechanisms of abscission, ethephon, an ethylene releasing substance, was applied at two concentrations (600 and 7200 ppm) during the midseason drop stage of mango. The abscission process is triggered by ethylene diffusing to the abscission zone where it binds to specific receptors and thereby activating several key physiological responses at the cellular level. The treatments reduced significantly the capacity of polar auxin transport through the pedicel at 1 day after treatment and thereafter when compared to untreated pedicels. The transcript levels of the ethylene receptor genes MiETR1 and MiERS1 were significantly upregulated in the pedicel and pericarp at 1, 2, and 3 days after the ethephon application with 7200 ppm, except for MiETR1 in the pedicel, when compared to untreated fruitlet. In contrast, ethephon applications with 600 ppm did not affect expression levels of MiETR1 in the pedicel and of MiERS1 in the pericarp; however, MiETR1 in the pericarp at day 2 and MiERS1 in the pedicel at days 2 and 3 were significantly upregulated over the controls. Moreover, two novel short versions of the MiERS1 were identified and detected more often in the pedicel of treated than untreated fruitlets at all sampling times. Sucrose concentration in the fruitlet pericarp was significantly reduced to the control at 2 days after both ethephon treatments. In conclusion, it is postulated that the ethephon-induced abscission process commences with a reduction of the polar auxin transport capacity in the pedicel, followed by an upregulation of ethylene receptors and finally a decrease of the sucrose concentration in the fruitlets. PMID:26442021

  13. Citron kinase controls abscission through RhoA and anillin

    PubMed Central

    Gai, Marta; Camera, Paola; Dema, Alessandro; Bianchi, Federico; Berto, Gaia; Scarpa, Elena; Germena, Giulia; Di Cunto, Ferdinando

    2011-01-01

    The small GTPase RhoA plays a crucial role in the different stages of cytokinesis, including contractile ring formation, cleavage furrow ingression, and midbody abscission. Citron kinase (CIT-K), a protein required for cytokinesis and conserved from insects to mammals, is currently considered a cytokinesis-specific effector of active RhoA. In agreement with previous observations, we show here that, as in Drosophila cells, CIT-K is specifically required for abscission in mammalian cells. However, in contrast with the current view, we provide evidence that CIT-K is an upstream regulator rather than a downstream effector of RhoA during late cytokinesis. In addition, we show that CIT-K is capable of physically and functionally interacting with the actin-binding protein anillin. Active RhoA and anillin are displaced from the midbody in CIT-K-depleted cells, while only anillin, but not CIT-K, is affected if RhoA is inactivated in late cytokinesis. The overexpression of CIT-K and of anillin leads to abscission delay. However, the delay produced by CIT-K overexpression can be reversed by RhoA inactivation, while the delay produced by anillin overexpression is RhoA-independent. Altogether, these results indicate that CIT-K is a crucial abscission regulator that may promote midbody stability through active RhoA and anillin. PMID:21849473

  14. Temporal and spatial expression of polygalacturonase gene family members reveals divergent regulation during fleshy fruit ripening and abscission in the monocot species oil palm.

    PubMed

    Roongsattham, Peerapat; Morcillo, Fabienne; Jantasuriyarat, Chatchawan; Pizot, Maxime; Moussu, Steven; Jayaweera, Dasuni; Collin, Myriam; Gonzalez-Carranza, Zinnia H; Amblard, Philippe; Tregear, James W; Tragoonrung, Somvong; Verdeil, Jean-Luc; Tranbarger, Timothy J

    2012-08-25

    Cell separation that occurs during fleshy fruit abscission and dry fruit dehiscence facilitates seed dispersal, the final stage of plant reproductive development. While our understanding of the evolutionary context of cell separation is limited mainly to the eudicot model systems tomato and Arabidopsis, less is known about the mechanisms underlying fruit abscission in crop species, monocots in particular. The polygalacturonase (PG) multigene family encodes enzymes involved in the depolymerisation of pectin homogalacturonan within the primary cell wall and middle lamella. PG activity is commonly found in the separation layers during organ abscission and dehiscence, however, little is known about how this gene family has diverged since the separation of monocot and eudicots and the consequence of this divergence on the abscission process. The objective of the current study was to identify PGs responsible for the high activity previously observed in the abscission zone (AZ) during fruit shedding of the tropical monocot oil palm, and to analyze PG gene expression during oil palm fruit ripening and abscission. We identified 14 transcripts that encode PGs, all of which are expressed in the base of the oil palm fruit. The accumulation of five PG transcripts increase, four decrease and five do not change during ethylene treatments that induce cell separation. One PG transcript (EgPG4) is the most highly induced in the fruit base, with a 700-5000 fold increase during the ethylene treatment. In situ hybridization experiments indicate that the EgPG4 transcript increases preferentially in the AZ cell layers in the base of the fruit in response to ethylene prior to cell separation. The expression pattern of EgPG4 is consistent with the temporal and spatial requirements for cell separation to occur during oil palm fruit shedding. The sequence diversity of PGs and the complexity of their expression in the oil palm fruit tissues contrast with data from tomato, suggesting

  15. Temporal and spatial expression of polygalacturonase gene family members reveals divergent regulation during fleshy fruit ripening and abscission in the monocot species oil palm

    PubMed Central

    2012-01-01

    Background Cell separation that occurs during fleshy fruit abscission and dry fruit dehiscence facilitates seed dispersal, the final stage of plant reproductive development. While our understanding of the evolutionary context of cell separation is limited mainly to the eudicot model systems tomato and Arabidopsis, less is known about the mechanisms underlying fruit abscission in crop species, monocots in particular. The polygalacturonase (PG) multigene family encodes enzymes involved in the depolymerisation of pectin homogalacturonan within the primary cell wall and middle lamella. PG activity is commonly found in the separation layers during organ abscission and dehiscence, however, little is known about how this gene family has diverged since the separation of monocot and eudicots and the consequence of this divergence on the abscission process. Results The objective of the current study was to identify PGs responsible for the high activity previously observed in the abscission zone (AZ) during fruit shedding of the tropical monocot oil palm, and to analyze PG gene expression during oil palm fruit ripening and abscission. We identified 14 transcripts that encode PGs, all of which are expressed in the base of the oil palm fruit. The accumulation of five PG transcripts increase, four decrease and five do not change during ethylene treatments that induce cell separation. One PG transcript (EgPG4) is the most highly induced in the fruit base, with a 700–5000 fold increase during the ethylene treatment. In situ hybridization experiments indicate that the EgPG4 transcript increases preferentially in the AZ cell layers in the base of the fruit in response to ethylene prior to cell separation. Conclusions The expression pattern of EgPG4 is consistent with the temporal and spatial requirements for cell separation to occur during oil palm fruit shedding. The sequence diversity of PGs and the complexity of their expression in the oil palm fruit tissues contrast with data

  16. Ethephon As a Potential Abscission Agent for Table Grapes: Effects on Pre-Harvest Abscission, Fruit Quality, and Residue

    PubMed Central

    Ferrara, Giuseppe; Mazzeo, Andrea; Matarrese, Angela M. S.; Pacucci, Carmela; Trani, Antonio; Fidelibus, Matthew W.; Gambacorta, Giuseppe

    2016-01-01

    Some plant growth regulators, including ethephon, can stimulate abscission of mature grape berries. The stimulation of grape berry abscission reduces fruit detachment force (FDF) and promotes the development of a dry stem scar, both of which could facilitate the production of high quality stemless fresh-cut table grapes. The objective of this research was to determine how two potential abscission treatments, 1445 and 2890 mg/L ethephon, affected FDF, pre-harvest abscission, fruit quality, and ethephon residue of Thompson Seedless and Crimson Seedless grapes. Both ethephon treatments strongly induced abscission of Thompson Seedless berries causing >90% pre-harvest abscission. Lower ethephon rates, a shorter post-harvest interval, or berry retention systems such as nets, would be needed to prevent excessive pre-harvest losses. The treatments also slightly affected Thompson Seedless berry skin color, with treated fruit being darker, less uniform in color, and with a more yellow hue than non-treated fruit. Ethephon residues on Thompson Seedless grapes treated with the lower concentration of ethephon were below legal limits at harvest. Ethephon treatments also promoted abscission of Crimson Seedless berries, but pre-harvest abscission was much lower (≅49%) in Crimson Seedless compared to Thompson Seedless. Treated fruits were slightly darker than non-treated fruits, but ethephon did not affect SSC, acidity, or firmness of Crimson Seedless, and ethephon residues were below legal limits. PMID:27303407

  17. Signaling Pathways Mediating the Induction of Apple Fruitlet Abscission1[C][W][OA

    PubMed Central

    Botton, Alessandro; Eccher, Giulia; Forcato, Claudio; Ferrarini, Alberto; Begheldo, Maura; Zermiani, Monica; Moscatello, Stefano; Battistelli, Alberto; Velasco, Riccardo; Ruperti, Benedetto; Ramina, Angelo

    2011-01-01

    Apple (Malus × domestica) represents an interesting model tree crop for studying fruit abscission. The physiological fruitlet drop occurring in this species can be easily magnified by using thinning chemicals, such as benzyladenine (BA), to obtain fruits with improved quality and marketability. Despite the economic importance of this process, the molecular determinants of apple fruitlet abscission are still unknown. In this research, BA was used to obtain fruitlet populations with different abscission potentials to be analyzed by means of a newly released 30K oligonucleotide microarray. RNAs were extracted from cortex and seed of apple fruitlets sampled over a 4-d time course, during which BA triggers fruit drop, and used for microarray hybridization. Transcriptomic profiles of persisting and abscising fruitlets were tested for statistical association with abscission potential, allowing us to identify molecular signatures strictly related to fruit destiny. A hypothetical model for apple fruitlet abscission was obtained by putting together available transcriptomic and metabolomic data. According to this model, BA treatment would establish a nutritional stress within the tree that is primarily perceived by the fruitlet cortex whose growth is blocked by resembling the ovary growth inhibition found in other species. In weaker fruits, this stress is soon visible also at the seed level, likely transduced via reactive oxygen species/sugar and hormones signaling cross talk, and followed by a block of embryogenesis and the consequent activation of the abscission zone. PMID:21037112

  18. Temporal and Spatial Expression of a Polygalacturonase during Leaf and Flower Abscission in Oilseed Rape and Arabidopsis1

    PubMed Central

    González-Carranza, Zinnia Haydé; Whitelaw, Catherine Ann; Swarup, Ranjan; Roberts, Jeremy Alan

    2002-01-01

    During leaf abscission in oilseed rape (Brassica napus), cell wall degradation is brought about by the action of several hydrolytic enzymes. One of these is thought to be polygalacturonase (PG). Degenerate primers were used to isolate a PG cDNA fragment by reverse transcriptase-polymerase chain reaction from RNA extracted from ethylene-promoted leaf abscission zones (AZs), and in turn a full-length clone (CAW471) from an oilseed rape AZ cDNA library. The highest homology of this cDNA (82%) was to an Arabidopsis sequence that was predicted to encode a PG protein. Analysis of expression revealed that CAW471 mRNA accumulated in the AZ of leaves and reached a peak 24 h after ethylene treatment. Ethylene-promoted leaf abscission in oilseed rape was not apparent until 42 h after exposure to the gas, reaching 50% at 48 h and 100% by 56 h. In floral organ abscission, expression of CAW471 correlated with cell separation. Genomic libraries from oilseed rape and Arabidopsis were screened with CAW471 and the respective genomic clones PGAZBRAN and PGAZAT isolated. Characterization of these PG genes revealed that they had substantial homology within both the coding regions and in the 5′-upstream sequences. Fusion of a 1,476-bp 5′-upstream sequence of PGAZAT to β-glucuronidase or green fluorescent protein and transformation of Arabidopsis revealed that this fragment was sufficient to drive expression of these reporter genes in the AZs at the base of the anther filaments, petals, and sepals. PMID:11842157

  19. Effect of Ethylene on Flower Abscission: a Survey

    PubMed Central

    VAN DOORN, WOUTER G.

    2002-01-01

    The effect of ethylene on flower abscission was investigated in monocotyledons and eudicotyledons, in about 300 species from 50 families. In all species studied except Cymbidium, flower abscission was highly sensitive to ethylene. Flower fall was not consistent among the species in any family studied. It also showed no relationship with petal senescence or abscission, nor with petal colour changes or flower closure. Results suggest that flower abscission is generally mediated by endogenous ethylene, but that some exceptional ethylene‐insensitive abscission occurs in the Orchidaceae. PMID:12102524

  20. The Phytotoxin Coronatine Induces Abscission-Related Gene Expression and Boll Ripening during Defoliation of Cotton

    PubMed Central

    Tian, Xiaoli; Duan, Liusheng; Zhang, Mingcai; Tan, Weiming; Xu, Dongyong; Li, Zhaohu

    2014-01-01

    Defoliants can increase machine harvest efficiency of cotton (Gossypium hirusutum L.), prevent lodging and reduce the time from defoliation to harvest. Coronatine (COR) is a chlorosis-inducing non-host-specific phytotoxin that induces leaf and/or fruit abscission in some crops. The present study investigates how COR might induce cotton leaf abscission by modulating genes involved in cell wall hydrolases and ACC (ethylene precursor) in various cotton tissues. The effects of COR on cotton boll ripening, seedcotton yield, and seed development were also studied. After 14 d of treatment with COR, cells within the leaf abscission zone (AZ) showed marked differentiation. Elevated transcripts of GhCEL1, GhPG and GhACS were observed in the AZs treated with COR and Thidiazuron (TDZ). The relative expression of GhCEL1 and GhACS in TDZ treated plants was approximately twice that in plants treated with COR for 12 h. However, only GhACS expression increased in leaf blade and petiole. There was a continuous increase in the activity of hydrolytic enzymes such as cellulase (CEL) and polygalacturonase (PG), and ACC accumulation in AZs following COR and TDZ treatments, but there was greater increase in ACC activity of COR treated boll crust, indicating that COR had greater ripening effect than TDZ. Coronatine significantly enhanced boll opening without affecting boll weight, lint percentage and seed quality. Therefore, COR can be a potential cotton defoliant with different physiological mechanism of action from the currently used TDZ. PMID:24845465

  1. Controlled free radical attack in the apoplast: a hypothesis for roles of O, N and S species in regulatory and polysaccharide cleavage events during rapid abscission by Azolla.

    PubMed

    Cohen, Michael F; Gurung, Sushma; Fukuto, Jon M; Yamasaki, Hideo

    2014-03-01

    Shedding of organs by abscission is a key terminal step in plant development and stress responses. Cell wall (CW) loosening at the abscission zone can occur through a combination chain breakage of apoplastic polysaccharides and tension release of cellulose microfibrils. Two distinctly regulated abscission cleavage events are amenable to study in small water ferns of the genus Azolla; one is a rapid abscission induced by environmental stimuli such as heat or chemicals, and the other is an ethylene-induced process occurring more slowly through the action of hydrolytic enzymes. Although free radicals are suggested to be involved in the induction of rapid root abscission, its mechanism is not fully understood. The apoplast contains peroxidases, metal-binding proteins and phenolic compounds that potentially generate free radicals from H2O2 to cleave polysaccharides in the CW and middle lamella. Effects of various thiol-reactive agents implicate the action of apoplastic peroxidases having accessible cysteine thiols in rapid abscission. The Ca(2+) dependency of rapid abscission may reflect the stabilization Ca(2+) confers to peroxidase structure and binding to pectin. To spur further investigation, we present a hypothetical model for small signaling molecules H2O2 and NO and their derivatives in regulating, via modification of putative protein thiols, free radical attack of apoplastic polysaccharides. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  2. Controlled free radical attack in the apoplast: A hypothesis for roles of O, N and S species in regulatory and polysaccharide cleavage events during rapid abscission by Azolla

    PubMed Central

    Cohen, Michael F.; Gurung, Sushma; Fukuto, Jon M.; Yamasaki, Hideo

    2014-01-01

    Shedding of organs by abscission is a key terminal step in plant development and stress responses. Cell wall (CW) loosening at the abscission zone can occur through a combination chain breakage of apoplastic polysaccharides and tension release of cellulose microfibrils. Two distinctly regulated abscission cleavage events are amenable to study in small water ferns of the genus Azolla; one is a rapid abscission induced by environmental stimuli such as heat or chemicals, and the other is an ethylene-induced process occurring more slowly through the action of hydrolytic enzymes. Although free radicals are suggested to be involved in the induction of rapid root abscission, its mechanism is not fully understood. The apoplast contains peroxidases, metal-binding proteins and phenolic compounds that potentially generate free radicals from H2O2 to cleave polysaccharides in the CW and middle lamella. Effects of various thiol-reactive agents implicate the action of apoplastic peroxidases having accessible cysteine thiols in rapid abscission. The Ca2+ dependency of rapid abscission may reflect the stabilization Ca2+ confers to peroxidase structure and binding to pectin. To spur further investigation, we present a hypothetical model for small signaling molecules H2O2 and NO and their derivatives in regulating, via modification of putative protein thiols, free radical attack of apoplastic polysaccharides. PMID:24467903

  3. Characterization and structural analysis of wild type and a non-abscission mutant at the development funiculus (Def) locus in Pisum sativum L.

    PubMed

    Ayeh, Kwadwo Owusu; Lee, YeonKyeong; Ambrose, Mike J; Hvoslef-Eide, Anne Kathrine

    2009-06-23

    In pea seeds (Pisum sativum L.), the Def locus defines an abscission event where the seed separates from the funicle through the intervening hilum region at maturity. A spontaneous mutation at this locus results in the seed failing to abscise from the funicle as occurs in wild type peas. In this work, structural differences between wild type peas that developed a distinct abscission zone (AZ) between the funicle and the seed coat and non-abscission def mutant were characterized. A clear abscission event was observed in wild type pea seeds that were associated with a distinct double palisade layers at the junction between the seed coat and funicle. Generally, mature seeds fully developed an AZ, which was not present in young wild type seeds. The AZ was formed exactly below the counter palisade layer. In contrast, the palisade layers at the junction of the seed coat and funicle were completely absent in the def mutant pea seeds and the cells in this region were seen to be extensions of surrounding parenchymatous cells. The Def wild type developed a distinct AZ associated with palisade layer and counterpalisade layer at the junction of the seed coat and funicle while the def mutant pea seed showed non-abscission and an absence of the double palisade layers in the same region. We conclude that the presence of the double palisade layer in the hilum of the wild type pea seeds plays an important structural role in AZ formation by delimiting the specific region between the seed coat and the funicle and may play a structural role in the AZ formation and subsequent detachment of the seed from the funicle.

  4. Polyamine-Induced Rapid Root Abscission in Azolla pinnata

    PubMed Central

    Gurung, Sushma; Cohen, Michael F.; Fukuto, Jon; Yamasaki, Hideo

    2012-01-01

    Floating ferns of the genus Azolla detach their roots under stress conditions, a unique adaptive response termed rapid root abscission. We found that Azolla pinnata plants exhibited dose-dependent rapid root abscission in response to the polyamines spermidine and spermine after a substantial time lag (>20 min). The duration of the time lag decreased in response to high pH and high temperature whereas high light intensity increased the time lag and markedly lowered the rate of abscission. The oxidation products of polyamines, 1,3-diaminopropane, β-alanine and hydrogen peroxide all failed to initiate root abscission, and hydroxyethyl hydrazine, an inhibitor of polyamine oxidase, did not inhibit spermine-induced root abscission. Exposure of A. pinnata to the polyamines did not result in detectable release of NO and did not affect nitrite-dependent NO production. The finding of polyamine-induced rapid root abscission provides a facile assay for further study of the mode of action of polyamines in plant stress responses. PMID:22997568

  5. Polyamine-Induced Rapid Root Abscission in Azolla pinnata.

    PubMed

    Gurung, Sushma; Cohen, Michael F; Fukuto, Jon; Yamasaki, Hideo

    2012-01-01

    Floating ferns of the genus Azolla detach their roots under stress conditions, a unique adaptive response termed rapid root abscission. We found that Azolla pinnata plants exhibited dose-dependent rapid root abscission in response to the polyamines spermidine and spermine after a substantial time lag (>20 min). The duration of the time lag decreased in response to high pH and high temperature whereas high light intensity increased the time lag and markedly lowered the rate of abscission. The oxidation products of polyamines, 1,3-diaminopropane, β-alanine and hydrogen peroxide all failed to initiate root abscission, and hydroxyethyl hydrazine, an inhibitor of polyamine oxidase, did not inhibit spermine-induced root abscission. Exposure of A. pinnata to the polyamines did not result in detectable release of NO and did not affect nitrite-dependent NO production. The finding of polyamine-induced rapid root abscission provides a facile assay for further study of the mode of action of polyamines in plant stress responses.

  6. The Tomato Hybrid Proline-Rich Protein regulates the abcission zone competence to respond to ethylene signals

    USDA-ARS?s Scientific Manuscript database

    The Tomato Hybrid Proline-Rich Protein (THyPRP) gene was specifically expressed in the tomato (Solanum lycopersicum) flower abscission zone (FAZ), and its stable antisense silencing under the control of an abscission zone (AZ)-specific promoter, Tomato Abscission Polygalacturonase4,significantly inh...

  7. Bimodal effect of hydrogen peroxide and oxidative events in nitrite-induced rapid root abscission by the water fern Azolla pinnata.

    PubMed

    Cohen, Michael F; Gurung, Sushma; Birarda, Giovanni; Holman, Hoi-Ying N; Yamasaki, Hideo

    2015-01-01

    In the genus Azolla rapid abscission of roots from floating fronds occurs within minutes in response to a variety of stresses, including exposure to nitrite. We found that hydrogen peroxide, though itself not an inducer of root abscission, modulates nitrite-induced root abscission by Azolla pinnata in a dose-dependent manner, with 2 mM H2O2 significantly diminishing the responsiveness to 2 mM NaNO2, and 10 mM H2O2 slightly enhancing it. Hypoxia, which has been found in other plants to result in autogenic production of H2O2, dramatically stimulated root abscission of A. pinnata in response to nitrite, especially for plants previously cultivated in medium containing 5 mM KNO3 compared to plants cultivated under N2-fixing conditions without combined nitrogen. Plants, including Azolla, produce the small signaling molecule nitric oxide (NO) from nitrite using nitrate reductase. We found Azolla plants to display dose-dependent root abscission in response to the NO donor spermine NONOate. Treatment of plants with the thiol-modifying agents S-methyl methanethiosulfonate or glutathione inhibited the nitrite-induced root abscission response. Synchrotron radiation-based Fourier transform infrared spectromicroscopy revealed higher levels of carbonylation in the abscission zone of dropped roots, indicative of reaction products of polysaccharides with potent free radical oxidants. We hypothesize that metabolic products of nitrite and NO react with H2O2 in the apoplast leading to free-radical-mediated cleavage of structural polysaccharides and consequent rapid root abscission.

  8. Bimodal effect of hydrogen peroxide and oxidative events in nitrite-induced rapid root abscission by the water fern Azolla pinnata

    PubMed Central

    Cohen, Michael F.; Gurung, Sushma; Birarda, Giovanni; Holman, Hoi-Ying N.; Yamasaki, Hideo

    2015-01-01

    In the genus Azolla rapid abscission of roots from floating fronds occurs within minutes in response to a variety of stresses, including exposure to nitrite. We found that hydrogen peroxide, though itself not an inducer of root abscission, modulates nitrite-induced root abscission by Azolla pinnata in a dose-dependent manner, with 2 mM H2O2 significantly diminishing the responsiveness to 2 mM NaNO2, and 10 mM H2O2 slightly enhancing it. Hypoxia, which has been found in other plants to result in autogenic production of H2O2, dramatically stimulated root abscission of A. pinnata in response to nitrite, especially for plants previously cultivated in medium containing 5 mM KNO3 compared to plants cultivated under N2-fixing conditions without combined nitrogen. Plants, including Azolla, produce the small signaling molecule nitric oxide (NO) from nitrite using nitrate reductase. We found Azolla plants to display dose-dependent root abscission in response to the NO donor spermine NONOate. Treatment of plants with the thiol-modifying agents S-methyl methanethiosulfonate or glutathione inhibited the nitrite-induced root abscission response. Synchrotron radiation-based Fourier transform infrared spectromicroscopy revealed higher levels of carbonylation in the abscission zone of dropped roots, indicative of reaction products of polysaccharides with potent free radical oxidants. We hypothesize that metabolic products of nitrite and NO react with H2O2 in the apoplast leading to free-radical-mediated cleavage of structural polysaccharides and consequent rapid root abscission. PMID:26217368

  9. Bimodal effect of hydrogen peroxide and oxidative events in nitrite-induced rapid root abscission by the water fern Azolla pinnata

    DOE PAGES

    Cohen, Michael F.; Gurung, Sushma; Birarda, Giovanni; ...

    2015-07-09

    In the genus Azolla rapid abscission of roots from floating fronds occurs within minutes in response to a variety of stresses, including exposure to nitrite. We found that hydrogen peroxide, though itself not an inducer of root abscission, modulates nitrite-induced root abscission by Azolla pinnata in a dose-dependent manner, with 2 mM H 2O 2 significantly diminishing the responsiveness to 2 mM NaNO 2, and 10 mM H 2O 2 slightly enhancing it. Hypoxia, which has been found in other plants to result in autogenic production of H 2O 2, dramatically stimulated root abscission of A. pinnata in response tomore » nitrite, especially for plants previously cultivated in medium containing 5 mM KNO 3 compared to plants cultivated under N 2-fixing conditions without combined nitrogen. Plants, including Azolla, produce the small signaling molecule nitric oxide (NO) from nitrite using nitrate reductase. We found Azolla plants to display dose-dependent root abscission in response to the NO donor spermine NONOate. Treatment of plants with the thiol-modifying agents S-methyl methanethiosulfonate or glutathione inhibited the nitrite-induced root abscission response. Synchrotron radiation-based Fourier transform infrared spectromicroscopy revealed higher levels of carbonylation in the abscission zone of dropped roots, indicative of reaction products of polysaccharides with potent free radical oxidants. Lastly, we hypothesize that metabolic products of nitrite and NO react with H 2O 2 in the apoplast leading to free-radical-mediated cleavage of structural polysaccharides and consequent rapid root abscission.« less

  10. HLB-associated preharvest fruit abscission is mediated by jasmonate/ethylene signaling triggered by secondary fungal infection

    USDA-ARS?s Scientific Manuscript database

    One symptom of citrus huanglongbing (HLB) is excessive pre-harvest fruit drop. Recently, higher incidence of Lasiodiplodia theobromae (Diplodia) was found in HLB-symptomatic orange calyx abscission zones (AZ-C) than in non-symptomatic fruit, and the infection was positively correlated with the reduc...

  11. A knotted1-like homeobox protein regulates abscission in tomato by modulating the auxin pathway

    USDA-ARS?s Scientific Manuscript database

    KD1, a gene encoding a KNOTTED1-LIKE HOMEOBOX transcription factor is known to be involved, in tomato, in ontogeny of the compound leaf. KD1 is also highly expressed in both leaf and flower abscission zones. Reducing abundance of transcripts of this gene in tomato, using both virus induced gene sile...

  12. Transcriptomics of shading-induced and NAA-induced abscission in apple (Malus domestica) reveals a shared pathway involving reduced photosynthesis, alterations in carbohydrate transport and signaling and hormone crosstalk

    PubMed Central

    2011-01-01

    Background Naphthaleneacetic acid (NAA), a synthetic auxin analogue, is widely used as an effective thinner in apple orchards. When applied shortly after fruit set, some fruit abscise leading to improved fruit size and quality. However, the thinning results of NAA are inconsistent and difficult to predict, sometimes leading to excess fruit drop or insufficient thinning which are costly to growers. This unpredictability reflects our incomplete understanding of the mode of action of NAA in promoting fruit abscission. Results Here we compared NAA-induced fruit drop with that caused by shading via gene expression profiling performed on the fruit abscission zone (FAZ), sampled 1, 3, and 5 d after treatment. More than 700 genes with significant changes in transcript abundance were identified from NAA-treated FAZ. Combining results from both treatments, we found that genes associated with photosynthesis, cell cycle and membrane/cellular trafficking were downregulated. On the other hand, there was up-regulation of genes related to ABA, ethylene biosynthesis and signaling, cell wall degradation and programmed cell death. While the differentially expressed gene sets for NAA and shading treatments shared only 25% identity, NAA and shading showed substantial similarity with respect to the classes of genes identified. Specifically, photosynthesis, carbon utilization, ABA and ethylene pathways were affected in both NAA- and shading-induced young fruit abscission. Moreover, we found that NAA, similar to shading, directly interfered with leaf photosynthesis by repressing photosystem II (PSII) efficiency within 10 minutes of treatment, suggesting that NAA and shading induced some of the same early responses due to reduced photosynthesis, which concurred with changes in hormone signaling pathways and triggered fruit abscission. Conclusions This study provides an extensive transcriptome study and a good platform for further investigation of possible regulatory genes involved in the

  13. Transcriptomics of shading-induced and NAA-induced abscission in apple (Malus domestica) reveals a shared pathway involving reduced photosynthesis, alterations in carbohydrate transport and signaling and hormone crosstalk.

    PubMed

    Zhu, Hong; Dardick, Chris D; Beers, Eric P; Callanhan, Ann M; Xia, Rui; Yuan, Rongcai

    2011-10-17

    Naphthaleneacetic acid (NAA), a synthetic auxin analogue, is widely used as an effective thinner in apple orchards. When applied shortly after fruit set, some fruit abscise leading to improved fruit size and quality. However, the thinning results of NAA are inconsistent and difficult to predict, sometimes leading to excess fruit drop or insufficient thinning which are costly to growers. This unpredictability reflects our incomplete understanding of the mode of action of NAA in promoting fruit abscission. Here we compared NAA-induced fruit drop with that caused by shading via gene expression profiling performed on the fruit abscission zone (FAZ), sampled 1, 3, and 5 d after treatment. More than 700 genes with significant changes in transcript abundance were identified from NAA-treated FAZ. Combining results from both treatments, we found that genes associated with photosynthesis, cell cycle and membrane/cellular trafficking were downregulated. On the other hand, there was up-regulation of genes related to ABA, ethylene biosynthesis and signaling, cell wall degradation and programmed cell death. While the differentially expressed gene sets for NAA and shading treatments shared only 25% identity, NAA and shading showed substantial similarity with respect to the classes of genes identified. Specifically, photosynthesis, carbon utilization, ABA and ethylene pathways were affected in both NAA- and shading-induced young fruit abscission. Moreover, we found that NAA, similar to shading, directly interfered with leaf photosynthesis by repressing photosystem II (PSII) efficiency within 10 minutes of treatment, suggesting that NAA and shading induced some of the same early responses due to reduced photosynthesis, which concurred with changes in hormone signaling pathways and triggered fruit abscission. This study provides an extensive transcriptome study and a good platform for further investigation of possible regulatory genes involved in the induction of young fruit

  14. Early Induction of Apple Fruitlet Abscission Is Characterized by an Increase of Both Isoprene Emission and Abscisic Acid Content12[W][OA

    PubMed Central

    Giulia, Eccher; Alessandro, Botton; Mariano, Dimauro; Andrea, Boschetti; Benedetto, Ruperti; Angelo, Ramina

    2013-01-01

    Apple (Malus domestica) fruitlet abscission represents an interesting model system to study the early phases of the shedding process, during which major transcriptomic changes and metabolic rearrangements occur within the fruit. In apple, the drop of fruits at different positions within the cluster can be selectively magnified through chemical thinners, such as benzyladenine and metamitron, acting as abscission enhancers. In this study, different abscission potentials were obtained within the apple fruitlet population by means of the above-cited thinners. A metabolomic study was conducted on the volatile organic compounds emitted by abscising fruitlets, allowing for identification of isoprene as an early marker of abscission induction. A strong correlation was also observed between isoprene production and abscisic acid (ABA) levels in the fruit cortex, which were shown to increase in abscising fruitlets with respect to nonabscising ones. Transcriptomic evidence indicated that abscission-related ABA is biologically active, and its increased biosynthesis is associated with the induction of a specific ABA-responsive 9-cis-epoxycarotenoid dioxygenase gene. According to a hypothetical model, ABA may transiently cooperate with other hormones and secondary messengers in the generation of an intrafruit signal leading to the downstream activation of the abscission zone. The shedding process therefore appears to be triggered by multiple interdependent pathways, whose fine regulation, exerted within a very short temporal window by both endogenous and exogenous factors, determines the final destiny of the fruitlets. PMID:23444344

  15. Comprehensive analysis of SAUR gene family in citrus and its transcriptional correlation with fruitlet drop from abscission zone A.

    PubMed

    Xie, Rangjin; Dong, Cuicui; Ma, Yanyan; Deng, Lie; He, Shaolan; Yi, Shilai; Lv, Qiang; Zheng, Yongqiang

    2015-11-01

    Small auxin-up RNA (SAUR) gene family is large, and the members of which can be rapidly induced by auxin and encode highly unstable mRNAs. SAUR genes are involved in various developmental and physiological processes, such as leaf senescence, fruitlet abscission, and hypocotyl development. However, their modes of action in citrus remain unknown. Hereby, a systematic analysis of SAUR gene family in citrus was conducted through a genome-wide search. In this study, a total of 70 SAUR genes, referred to as CitSAURs, have been identified in citrus. The evolutionary relationship and the intro-exon organization were analyzed, revealing strong gene conservation and the expansion of particular functional genes during plant evolution. Expression analysis showed that the major of CitSAUR genes were expressed in at least one tissue and showed distinctive expression levels, indicating the SAUR gene family play important roles in the development and growth of citrus organs. However, there were more than 20 CitSAUR genes such as CitSARU36, CitSAUR37, and CitSAUR54 exhibiting very low expression level in all tissue tested. Twenty-three out of 70 CitSAUR genes were responded to indole-3-acetic acid (IAA) treatment, of which just CitSAUR19 was down-regulated. Additionally, 14 CitSAUR genes exhibited distinct changes during fruitlet abscission, however just 5 of them including CitSAUR06, CitSAUR08, CitSAUR44, CitSAUR61, and CitSAUR64 were associated with fruitlet abscission. The current study provides basic information for the citrus SAUR gene family and will pave the way for deciphering the precise role of SAURs in citrus development and growth as well as fruitlet abscission.

  16. FOREVER YOUNG FLOWER Negatively Regulates Ethylene Response DNA-Binding Factors by Activating an Ethylene-Responsive Factor to Control Arabidopsis Floral Organ Senescence and Abscission.

    PubMed

    Chen, Wei-Han; Li, Pei-Fang; Chen, Ming-Kun; Lee, Yung-I; Yang, Chang-Hsien

    2015-08-01

    In this study of Arabidopsis (Arabidopsis thaliana), we investigated the relationship between FOREVER YOUNG FLOWER (FYF) and Ethylene Response DNA-binding Factors (EDFs) and functionally analyzed a key FYF target, an Ethylene-Responsive Factor (ERF), that controls flower senescence/abscission. Ectopic expression of EDF1/2/3/4 caused promotion of flower senescence/abscission and the activation of the senescence-associated genes. The presence of a repressor domain in EDFs and the enhancement of the promotion of senescence/abscission in EDF1/2/3/4+SRDX (converting EDFs to strong repressors by fusion with the ERF-associated amphiphilic repression motif repression domain SRDX) transgenic plants suggested that EDFs act as repressors. The significant reduction of β-glucuronidase (GUS) expression by 35S:FYF in EDF1/2/3/4:GUS plants indicates that EDF1/2/3/4 functions downstream of FYF in regulating flower senescence/abscission. In this study, we also characterized an ERF gene, FOREVER YOUNG FLOWER UP-REGULATING FACTOR1 (FUF1), which is up-regulated by FYF during flower development. Ectopic expression of FUF1 caused similar delayed flower senescence/abscission as seen in 35S:FYF plants. This phenotype was correlated with deficient abscission zone formation, ethylene insensitivity, and down-regulation of EDF1/2/3/4 and abscission-associated genes in 35S:FUF1 flowers. In contrast, significant promotion of flower senescence/abscission and up-regulation of EDF1/2/3/4 were observed in 35S:FUF1+SRDX transgenic dominant-negative plants, in which FUF1 is converted to a potent repressor by fusion to an SRDX-suppressing motif. Thus, FUF1 acts as an activator in suppressing EDF1/2/3/4 function and senescence/abscission of the flowers. Our results reveal that FYF regulates flower senescence/abscission by negatively regulating EDF1/2/3/4, which is the downstream gene in the ethylene response, by activating FUF1 in Arabidopsis. © 2015 American Society of Plant Biologists. All Rights

  17. Deer predation on leaf miners via leaf abscission

    NASA Astrophysics Data System (ADS)

    Yamazaki, Kazuo; Sugiura, Shinji

    2008-03-01

    The evergreen oak Quercus gilva Blume sheds leaves containing mines of the leaf miner Stigmella sp. (Lepidoptera: Nepticulidae) earlier than leaves with no mines in early spring in Nara, central Japan. The eclosion rates of the leaf miner in abscised and retained leaves were compared in the laboratory to clarify the effects of leaf abscission on leaf miner survival in the absence of deer. The leaf miner eclosed successfully from both fallen leaves and leaves retained on trees. However, sika deer ( Cervus nippon centralis Kishida) feed on the fallen mined leaves. Field observations showed that deer consume many fallen leaves under Q. gilva trees, suggesting considerable mortality of leaf miners due to deer predation via leaf abscission. This is a previously unreported relationship between a leaf miner and a mammalian herbivore via leaf abscission.

  18. FOREVER YOUNG FLOWER Negatively Regulates Ethylene Response DNA-Binding Factors by Activating an Ethylene-Responsive Factor to Control Arabidopsis Floral Organ Senescence and Abscission1

    PubMed Central

    Li, Pei-Fang; Lee, Yung-I; Yang, Chang-Hsien

    2015-01-01

    In this study of Arabidopsis (Arabidopsis thaliana), we investigated the relationship between FOREVER YOUNG FLOWER (FYF) and Ethylene Response DNA-binding Factors (EDFs) and functionally analyzed a key FYF target, an Ethylene-Responsive Factor (ERF), that controls flower senescence/abscission. Ectopic expression of EDF1/2/3/4 caused promotion of flower senescence/abscission and the activation of the senescence-associated genes. The presence of a repressor domain in EDFs and the enhancement of the promotion of senescence/abscission in EDF1/2/3/4+SRDX (converting EDFs to strong repressors by fusion with the ERF-associated amphiphilic repression motif repression domain SRDX) transgenic plants suggested that EDFs act as repressors. The significant reduction of β-glucuronidase (GUS) expression by 35S:FYF in EDF1/2/3/4:GUS plants indicates that EDF1/2/3/4 functions downstream of FYF in regulating flower senescence/abscission. In this study, we also characterized an ERF gene, FOREVER YOUNG FLOWER UP-REGULATING FACTOR1 (FUF1), which is up-regulated by FYF during flower development. Ectopic expression of FUF1 caused similar delayed flower senescence/abscission as seen in 35S:FYF plants. This phenotype was correlated with deficient abscission zone formation, ethylene insensitivity, and down-regulation of EDF1/2/3/4 and abscission-associated genes in 35S:FUF1 flowers. In contrast, significant promotion of flower senescence/abscission and up-regulation of EDF1/2/3/4 were observed in 35S:FUF1+SRDX transgenic dominant-negative plants, in which FUF1 is converted to a potent repressor by fusion to an SRDX-suppressing motif. Thus, FUF1 acts as an activator in suppressing EDF1/2/3/4 function and senescence/abscission of the flowers. Our results reveal that FYF regulates flower senescence/abscission by negatively regulating EDF1/2/3/4, which is the downstream gene in the ethylene response, by activating FUF1 in Arabidopsis. PMID:26063506

  19. Identifying the candidate genes involved in the calyx abscission process of 'Kuerlexiangli' (Pyrus sinkiangensis Yu) by digital transcript abundance measurements.

    PubMed

    Qi, Xiaoxiao; Wu, Jun; Wang, Lifen; Li, Leiting; Cao, Yufen; Tian, Luming; Dong, Xingguang; Zhang, Shaoling

    2013-10-23

    'Kuerlexiangli' (Pyrus sinkiangensis Yu), a native pear of Xinjiang, China, is an important agricultural fruit and primary export to the international market. However, fruit with persistent calyxes affect fruit shape and quality. Although several studies have looked into the physiological aspects of the calyx abscission process, the underlying molecular mechanisms remain unknown. In order to better understand the molecular basis of the process of calyx abscission, materials at three critical stages of regulation, with 6000 × Flusilazole plus 300 × PBO treatment (calyx abscising treatment) and 50 mg.L-1GA3 treatment (calyx persisting treatment), were collected and cDNA fragments were sequenced using digital transcript abundance measurements to identify candidate genes. Digital transcript abundance measurements was performed using high-throughput Illumina GAII sequencing on seven samples that were collected at three important stages of the calyx abscission process with chemical agent treatments promoting calyx abscission and persistence. Altogether more than 251,123,845 high quality reads were obtained with approximately 8.0 M raw data for each library. The values of 69.85%-71.90% of clean data in the digital transcript abundance measurements could be mapped to the pear genome database. There were 12,054 differentially expressed genes having Gene Ontology (GO) terms and associating with 251 Kyoto Encyclopedia of Genes and Genomes (KEGG) defined pathways. The differentially expressed genes correlated with calyx abscission were mainly involved in photosynthesis, plant hormone signal transduction, cell wall modification, transcriptional regulation, and carbohydrate metabolism. Furthermore, candidate calyx abscission-specific genes, e.g. Inflorescence deficient in abscission gene, were identified. Quantitative real-time PCR was used to confirm the digital transcript abundance measurements results. We identified candidate genes that showed highly dynamic changes in

  20. Drought effects on leaf abscission and leaf production in Populus clones

    Treesearch

    Stephen G. Pallardy; Julie L. Rhoads

    1997-01-01

    Leaf abscission and foliation responses to water stress were studied in potted plants of five Populus clones grown in a greenhouse. As predawn leaf water potential (Ψ1) fell to -3 MPa, drought-induced leaf abscission increased progressively to 30% for data pooled across clones. As predawn Ψ1...

  1. Shared and divergent pathways for flower abscission are triggered by gibberellic acid and carbon starvation in seedless Vitis vinifera L.

    PubMed

    Domingos, Sara; Fino, Joana; Cardoso, Vânia; Sánchez, Claudia; Ramalho, José C; Larcher, Roberto; Paulo, Octávio S; Oliveira, Cristina M; Goulao, Luis F

    2016-02-01

    Abscission is a highly coordinated developmental process by which plants control vegetative and reproductive organs load. Aiming at get new insights on flower abscission regulation, changes in the global transcriptome, metabolome and physiology were analyzed in 'Thompson Seedless' grapevine (Vitis vinifera L.) inflorescences, using gibberellic acid (GAc) spraying and shading as abscission stimuli, applied at bloom. Natural flower drop rates increased from 63.1% in non-treated vines to 83% and 99% in response to GAc and shade treatments, respectively. Both treatments had a broad effect on inflorescences metabolism. Specific impacts from shade included photosynthesis inhibition, associated nutritional stress, carbon/nitrogen imbalance and cell division repression, whereas GAc spraying induced energetic metabolism simultaneously with induction of nucleotide biosynthesis and carbon metabolism, therefore, disclosing alternative mechanisms to regulate abscission. Regarding secondary metabolism, changes in flavonoid metabolism were the most represented metabolic pathways in the samples collected following GAc treatment while phenylpropanoid and stilbenoid related pathways were predominantly affected in the inflorescences by the shade treatment. However, both GAc and shade treated inflorescences revealed also shared pathways, that involved the regulation of putrescine catabolism, the repression of gibberellin biosynthesis, the induction of auxin biosynthesis and the activation of ethylene signaling pathways and antioxidant mechanisms, although often the quantitative changes occurred on specific transcripts and metabolites of the pathways. Globally, the results suggest that chemical and environmental cues induced contrasting effects on inflorescence metabolism, triggering flower abscission by different mechanisms and pinpointing the participation of novel abscission regulators. Grapevine showed to be considered a valid model to study molecular pathways of flower abscission

  2. High-resolution transcript profiling reveals shoot abscission process of spruce dwarf mistletoe Arceuthobium sichuanense in response to ethephon

    PubMed Central

    Wang, Yonglin; Xiong, Dianguang; Jiang, Ning; Li, Xuewu; Yang, Qiqing; Tian, Chengming

    2016-01-01

    Arceuthobium (dwarf mistletoes) are hemiparasites that may cause great damage to infected trees belonging to Pinaceae and Cupressaceae. Currently, dwarf mistletoe control involves the use of the ethylene-producing product ethephon (ETH), which acts by inducing dwarf mistletoe shoot abscission. However, the process by which ETH functions is mostly unknown. Therefore, the transcriptome of the ETH-exposed plants was compared to non-exposed controls to identify genes associated with the response to ethephon. In this study, the reference transcriptome was contained 120,316 annotated unigenes, with a total of 21,764 ETH-responsive differentially expressed unigenes were identified. These ETH-associated genes clustered into 20 distinctly expressed pattern groups, providing a view of molecular events with good spatial and temporal resolution. As expected, the greatest number of unigenes with changed expression were observed at the onset of abscission, suggesting induction by ethylene. ETH also affected genes associated with shoot abscission processes including hormone biosynthesis and signaling, cell wall hydrolysis and modification, lipid transference, and more. The comprehensive transcriptome data set provides a wealth of genomic resources for dwarf mistletoe communities and contributes to a better understanding of the molecular regulatory mechanism of ethylene-caused shoots abscission. PMID:27941945

  3. Roles of Ethylene Production and Ethylene Receptor Expression in Regulating Apple Fruitlet Abscission1[OPEN

    PubMed Central

    Eccher, Giulia; Begheldo, Maura; Boschetti, Andrea; Ruperti, Benedetto; Botton, Alessandro

    2015-01-01

    Apple (Malus × domestica) is increasingly being considered an interesting model species for studying early fruit development, during which an extremely relevant phenomenon, fruitlet abscission, may occur as a response to both endogenous and/or exogenous cues. Several studies were carried out shedding light on the main physiological and molecular events leading to the selective release of lateral fruitlets within a corymb, either occurring naturally or as a result of a thinning treatment. Several studies pointed out a clear association between a rise of ethylene biosynthetic levels in the fruitlet and its tendency to abscise. A direct mechanistic link, however, has not yet been established between this gaseous hormone and the generation of the abscission signal within the fruit. In this work, the role of ethylene during the very early stages of abscission induction was investigated in fruitlet populations with different abscission potentials due either to the natural correlative inhibitions determining the so-called physiological fruit drop or to a well-tested thinning treatment performed with the cytokinin benzyladenine. A crucial role was ascribed to the ratio between the ethylene produced by the cortex and the expression of ethylene receptor genes in the seed. This ratio would determine the final probability to abscise. A working model has been proposed consistent with the differential distribution of four receptor transcripts within the seed, which resembles a spatially progressive cell-specific immune-like mechanism evolved by apple to protect the embryo from harmful ethylene. PMID:25888617

  4. Control of Abscission in Agricultural Crops and Its Physiological Basis 1

    PubMed Central

    Cooper, W. C.; Rasmussen, G. K.; Rogers, B. J.; Reece, P. C.; Henry, W. H.

    1968-01-01

    Some naphthalene and phenoxy compounds prevent preharvest drop of apples, pears, and citrus fruits. These studies have been complicated by an unrecognized high level of ethylene produced by leaves and fruit on trees sprayed with these growth regulators. An apparent contradiction is the effectiveness of both 2,4-dichlorophenoxyacetic acid and n-dimethylaminosuccinamic acid (a growth retardant which retards biosynthesis of auxin) in preventing abscission of apples. Thus, in the presence of low auxin concentrations in the tissue, this growth retardant prevents fruit abscission even more effectively than 2,4-dichlorophenoxyacetic acid at high auxin concentrations in the tissue. This anomaly is clarified on the basis that n-dimethylaminosuccinamic acid, in the presence of a known low ethylene biosynthesis, delays maturity of the fruit and thus prevents fruit abscission. On the other hand, 2,4-dichlorophenoxyacetic acid prevents abscission by direct growth hormone action, in spite of the side effects of ethylene production which speeds ripening of the fruit. With the promotion of abscission of leaves and fruit of agricultural crops, attention is given to the use of chemicals which induce ethylene production when applied to the plant, but which have no growth promotion effect to retard abscission. We can distinguish 5 kinds of such chemicals. One group includes gibberellic and abscisic acids that induce treated leaves to produce ethylene and abscise (under certain circumstances). However, they do not induce ethylene production by fruit and do not promote fruit abscission. A second group includes ascorbic acid, which, when used at relatively high levels, induces fruit to produce enough ethylene to promote abscission. Ascorbic acid-treated leaves also produce ethylene but not enough to cause much defoliation. A third group includes protein-synthesis inhibitors, such as cycloheximide. When low concentrations (about 30 μmoles/l) are sprayed on the fruit, the rapid effect of

  5. Implications of nonrandom seed abscission and global stilling for migration of wind-dispersed plant species.

    PubMed

    Thompson, Sally E; Katul, Gabriel G

    2013-06-01

    Migration of plant populations is a potential survival response to climate change that depends critically on seed dispersal. Biological and physical factors determine dispersal and migration of wind-dispersed species. Recent field and wind tunnel studies demonstrate biological adaptations that bias seed release toward conditions of higher wind velocity, promoting longer dispersal distances and faster migration. However, another suite of international studies also recently highlighted a global decrease in near-surface wind speeds, or 'global stilling'. This study assessed the implications of both factors on potential plant population migration rates, using a mechanistic modeling framework. Nonrandom abscission was investigated using models of three seed release mechanisms: (i) a simple drag model; (ii) a seed deflection model; and (iii) a 'wear and tear' model. The models generated a single functional relationship between the frequency of seed release and statistics of the near-surface wind environment, independent of the abscission mechanism. An Inertial-Particle, Coupled Eulerian-Lagrangian Closure model (IP-CELC) was used to investigate abscission effects on seed dispersal kernels and plant population migration rates under contemporary and potential future wind conditions (based on reported global stilling trends). The results confirm that nonrandom seed abscission increased dispersal distances, particularly for light seeds. The increases were mitigated by two physical feedbacks: (i) although nonrandom abscission increased the initial acceleration of seeds from rest, the sensitivity of the seed dispersal to this initial condition declined as the wind speed increased; and (ii) while nonrandom abscission increased the mean dispersal length, it reduced the kurtosis of seasonal dispersal kernels, and thus the chance of long-distance dispersal. Wind stilling greatly reduced the modeled migration rates under biased seed release conditions. Thus, species that require

  6. Timing is everything: early degradation of abscission layer is associated with increased seed shattering in U.S. weedy rice

    PubMed Central

    2011-01-01

    Background Seed shattering, or shedding, is an important fitness trait for wild and weedy grasses. U.S. weedy rice (Oryza sativa) is a highly shattering weed, thought to have evolved from non-shattering cultivated ancestors. All U.S. weedy rice individuals examined to date contain a mutation in the sh4 locus associated with loss of shattering during rice domestication. Weedy individuals also share the shattering trait with wild rice, but not the ancestral shattering mutation at sh4; thus, how weedy rice reacquired the shattering phenotype is unknown. To establish the morphological basis of the parallel evolution of seed shattering in weedy rice and wild, we examined the abscission layer at the flower-pedicel junction in weedy individuals in comparison with wild and cultivated relatives. Results Consistent with previous work, shattering wild rice individuals possess clear, defined abscission layers at flowering, whereas non-shattering cultivated rice individuals do not. Shattering weedy rice from two separately evolved populations in the U.S. (SH and BHA) show patterns of abscission layer formation and degradation distinct from wild rice. Prior to flowering, the abscission layer has formed in all weedy individuals and by flowering it is already degrading. In contrast, wild O. rufipogon abscission layers have been shown not to degrade until after flowering has occurred. Conclusions Seed shattering in weedy rice involves the formation and degradation of an abscission layer in the flower-pedicel junction, as in wild Oryza, but is a developmentally different process from shattering in wild rice. Weedy rice abscission layers appear to break down earlier than wild abscission layers. The timing of weedy abscission layer degradation suggests that unidentified regulatory genes may play a critical role in the reacquisition of shattering in weedy rice, and sheds light on the morphological basis of parallel evolution for shattering in weedy and wild rice. PMID:21235796

  7. Timing is everything: early degradation of abscission layer is associated with increased seed shattering in U.S. weedy rice.

    PubMed

    Thurber, Carrie S; Hepler, Peter K; Caicedo, Ana L

    2011-01-14

    Seed shattering, or shedding, is an important fitness trait for wild and weedy grasses. U.S. weedy rice (Oryza sativa) is a highly shattering weed, thought to have evolved from non-shattering cultivated ancestors. All U.S. weedy rice individuals examined to date contain a mutation in the sh4 locus associated with loss of shattering during rice domestication. Weedy individuals also share the shattering trait with wild rice, but not the ancestral shattering mutation at sh4; thus, how weedy rice reacquired the shattering phenotype is unknown. To establish the morphological basis of the parallel evolution of seed shattering in weedy rice and wild, we examined the abscission layer at the flower-pedicel junction in weedy individuals in comparison with wild and cultivated relatives. Consistent with previous work, shattering wild rice individuals possess clear, defined abscission layers at flowering, whereas non-shattering cultivated rice individuals do not. Shattering weedy rice from two separately evolved populations in the U.S. (SH and BHA) show patterns of abscission layer formation and degradation distinct from wild rice. Prior to flowering, the abscission layer has formed in all weedy individuals and by flowering it is already degrading. In contrast, wild O. rufipogon abscission layers have been shown not to degrade until after flowering has occurred. Seed shattering in weedy rice involves the formation and degradation of an abscission layer in the flower-pedicel junction, as in wild Oryza, but is a developmentally different process from shattering in wild rice. Weedy rice abscission layers appear to break down earlier than wild abscission layers. The timing of weedy abscission layer degradation suggests that unidentified regulatory genes may play a critical role in the reacquisition of shattering in weedy rice, and sheds light on the morphological basis of parallel evolution for shattering in weedy and wild rice.

  8. Differential effects of NAA and 2,4-D in reducing floret abscission in cestrum (Cestrum elegans) cut flowers are associated with their differential activation of Aux/IAA homologous genes.

    PubMed

    Abebie, Bekele; Lers, Amnon; Philosoph-Hadas, Sonia; Goren, Raphael; Riov, Joseph; Meir, Shimon

    2008-01-01

    A previous study showed that the relative effectiveness of 2,4-dichlorophenoxyacetic acid (2,4-D) compared with that of 1-naphthaleneacetic acid (NAA) in reducing floret bud abscission in cestrum (Cestrum elegans) cut flowers was due to its acropetal transport. The aim of the present study was to examine if the differential effect of these auxins on floret abscission is reflected in the expression of Aux/IAA genes in the floret abscission zone (AZ). cDNAs were isolated by PCR-based cloning from the floret AZ of auxin-treated cut flowers. The expression patterns of the cDNAs in various tissues and the effect of indole-3-acetic acid (IAA), applied with or without cycloheximide, on their expression in the floret AZ were examined by northern blot analysis. The regulation of transcript accumulation in the floret AZ in response to NAA or 2,4-D was measured by real-time PCR during auxin pulsing of cut flowers and vase life, concomitantly with floret abscission. Six isolated cDNAs were identified to represent Aux/IAA homologous genes, designated as Cestrum elegans (Ce)-IAA1 to Ce-IAA6. Four Ce-IAA genes were characterized as early auxin-responsive genes (ARGs), and two (Ce-IAA1 and Ce-IAA5) as late ARGs. Only Ce-IAA5 was AZ-specific in floret buds. A temporal regulation of Ce-IAA transcript levels in the floret AZ was found, with 2,4-D inducing higher expression levels than NAA in floret buds. These Ce-IAA expression levels were negatively correlated with floret abscission. The differential transport characteristics of NAA and 2,4-D in cestrum cut flowers were reflected in differential activation of the Ce-IAA genes identified in the floret AZ. Therefore, Aux/IAA genes can be used as molecular markers to measure auxin activity, which reflects free auxin level in the AZ. Two of the identified genes, Ce-IAA1 and Ce-IAA5, may also have a regulatory role in abscission.

  9. Cellulase and cell differentiation in Acer pseudoplatanus.

    PubMed

    Sheldrake, A R

    1970-06-01

    Homogenates of differentiating xylem and phloem tissue have higher cellulase activities than cambial samples; the highest activity is always found in phloem. Callus tissue, in which no vascular differentiation occurs, contains only low cellulase activity. The results suggest that cellulase is involved in vascular differentiation. Different pH optima of cellulase activity were found: in cambium, xylem and phloem tissue, cellulase activity with an optimum at about pH 5.9 is predominantly membrane-bound; it is sedimentable at 100,000 g and releasable by Triton X-100. The same may be true of activity with an optimum at pH 5.3. Phloem tissue also contains a soluble, cytoplasmic cellulase of high activity at pH 7.1, and xylem tissue contains cytoplasmic cellulase with an optimum at pH 6.5. Low cellulase activity with a pH optimum similar to that of xylem homogenates was found in xylem sap. Cellulase activity in abscission zones increases greatly just before leaf abscission. Abscission zone cellulase has two pH optima, et 5.3 and 5.9; both activities are increased by Triton treatment of homogenates. The possible existence of several different cellulases forming part of a cellulase complex, and the rôle of the enzymes in hydrolysing wall material during cell differentiation are discussed.

  10. Leaf Abscission Induced by Ethylene in Water-Stressed Intact Seedlings of Cleopatra Mandarin Requires Previous Abscisic Acid Accumulation in Roots.

    PubMed Central

    Gomez-Cadenas, A.; Tadeo, F. R.; Talon, M.; Primo-Millo, E.

    1996-01-01

    The involvement of abscisic acid (ABA) in the process of leaf abscission induced by 1-aminocyclopropane-1-carboxylic acid (ACC) transported from roots to shoots in Cleopatra mandarin (Citrus reshni Hort. ex Tan.) seedlings grown under water stress was studied using norflurazon (NF). Water stress induced both ABA (24-fold) and ACC (16-fold) accumulation in roots and arrested xylem flow. Leaf bulk ABA also increased (8-fold), although leaf abscission did not occur. Shortly after rehydration, root ABA and ACC returned to their prestress levels, whereas sharp and transitory increases of ACC (17-fold) and ethylene (10-fold) in leaves and high percentages of abscission (up to 47%) were observed. NF suppressed the ABA and ACC accumulation induced by water stress in roots and the sharp increases of ACC and ethylene observed after rewatering in leaves. NF also reduced leaf abscission (7-10%). These results indicate that water stress induces root ABA accumulation and that this is required for the process of leaf abscission to occur. It was also shown that exogenous ABA increases ACC levels in roots but not in leaves. Collectively, the data suggest that ABA, the primary sensitive signal to water stress, modulates the levels of ethylene, which is the hormonal activator of leaf abscission. This assumption implies that root ACC levels are correlated with root ABA amounts in a dependent way, which eventually links water status to an adequate, protective response such as leaf abscission. PMID:12226398

  11. Transcriptomic signatures in seeds of apple (Malus domestica L. Borkh) during fruitlet abscission.

    PubMed

    Ferrero, Sergio; Carretero-Paulet, Lorenzo; Mendes, Marta Adelina; Botton, Alessandro; Eccher, Giulia; Masiero, Simona; Colombo, Lucia

    2015-01-01

    Abscission is the regulated process of detachment of an organ from a plant. In apple the abscission of fruits occurs during their early development to control the fruit load depending on the nutritional state of the plant. In order to control production and obtain fruits with optimal market qualities, the horticultural procedure of thinning is performed to further reduce the number of fruitlets. In this study we have conducted a transcriptomic profiling of seeds from two different types of fruitlets, according to size and position in the fruit cluster. Transcriptomic profiles of central and lateral fruit seeds were obtained by RNAseq. Comparative analysis was performed by the functional categorization of differentially expressed genes by means of Gene Ontology (GO) annotation of the apple genome. Our results revealed the overexpression of genes involved in responses to stress, hormone biosynthesis and also the response and/or transport of auxin and ethylene. A smaller set of genes, mainly related to ion transport and homeostasis, were found to be down-regulated. The transcriptome characterization described in this manuscript contributes to unravelling the molecular mechanisms and pathways involved in the physiological abscission of apple fruits and suggests a role for seeds in this process.

  12. Transcriptomic Signatures in Seeds of Apple (Malus domestica L. Borkh) during Fruitlet Abscission

    PubMed Central

    Ferrero, Sergio; Carretero-Paulet, Lorenzo; Mendes, Marta Adelina; Botton, Alessandro; Eccher, Giulia; Masiero, Simona; Colombo, Lucia

    2015-01-01

    Abscission is the regulated process of detachment of an organ from a plant. In apple the abscission of fruits occurs during their early development to control the fruit load depending on the nutritional state of the plant. In order to control production and obtain fruits with optimal market qualities, the horticultural procedure of thinning is performed to further reduce the number of fruitlets. In this study we have conducted a transcriptomic profiling of seeds from two different types of fruitlets, according to size and position in the fruit cluster. Transcriptomic profiles of central and lateral fruit seeds were obtained by RNAseq. Comparative analysis was performed by the functional categorization of differentially expressed genes by means of Gene Ontology (GO) annotation of the apple genome. Our results revealed the overexpression of genes involved in responses to stress, hormone biosynthesis and also the response and/or transport of auxin and ethylene. A smaller set of genes, mainly related to ion transport and homeostasis, were found to be down-regulated. The transcriptome characterization described in this manuscript contributes to unravelling the molecular mechanisms and pathways involved in the physiological abscission of apple fruits and suggests a role for seeds in this process. PMID:25781174

  13. CsPLDalpha1 and CsPLDgamma1 are differentially induced during leaf and fruit abscission and diurnally regulated in Citrus sinensis.

    PubMed

    Malladi, Anish; Burns, Jacqueline K

    2008-01-01

    Understanding leaf and fruit abscission is essential in order to develop strategies for controlling the process in fruit crops. Mechanisms involved in signalling leaf and fruit abscission upon induction by abscission agents were investigated in Citrus sinensis cv. 'Valencia'. Previous studies have suggested a role for phospholipid signalling; hence, two phospholipase D cDNA sequences, CsPLDalpha1 and CsPLDgamma1, were isolated and their role was examined. CsPLDalpha1 expression was reduced in leaves but unaltered in fruit peel tissue treated with an ethylene-releasing compound (ethephon), or a fruit-specific abscission agent, 5-chloro-3-methyl-4-nitro-1H-pyrazole (CMNP). By contrast, CsPLDgamma1 expression was up-regulated within 6 h (leaves) and 24 h (fruit peel) after treatment with ethephon or CMNP, respectively. CsPLDalpha1 expression was diurnally regulated in leaf blade but not fruit peel. CsPLDgamma1 exhibited strong diurnal oscillation in expression in leaves and fruit peel with peak expression around midday. While diurnal fluctuation in CsPLDalpha1 expression appeared to be light-entrained in leaves, CsPLDgamma1 expression was regulated by light and the circadian clock. The diurnal expression of both genes was modulated by ethylene-signalling. The ethephon-induced leaf abscission and the ethephon- and CMNP-induced decrease in fruit detachment force were enhanced by application during rising diurnal expression of CsPLDgamma1. The results indicate differential regulation of CsPLDalpha1 and CsPLDgamma1 in leaves and fruit, and suggest possible roles for PLD-dependent signalling in regulating abscission responses in citrus.

  14. Flower abscission in Vitis vinifera L. triggered by gibberellic acid and shade discloses differences in the underlying metabolic pathways

    PubMed Central

    Domingos, Sara; Scafidi, Pietro; Cardoso, Vania; Leitao, Antonio E.; Di Lorenzo, Rosario; Oliveira, Cristina M.; Goulao, Luis F.

    2015-01-01

    Understanding abscission is both a biological and an agronomic challenge. Flower abscission induced independently by shade and gibberellic acid (GAc) sprays was monitored in grapevine (Vitis vinifera L.) growing under a soilless greenhouse system during two seasonal growing conditions, in an early and late production cycle. Physiological and metabolic changes triggered by each of the two distinct stimuli were determined. Environmental conditions exerted a significant effect on fruit set as showed by the higher natural drop rate recorded in the late production cycle with respect to the early cycle. Shade and GAc treatments increased the percentage of flower drop compared to the control, and at a similar degree, during the late production cycle. The reduction of leaf gas exchanges under shade conditions was not observed in GAc treated vines. The metabolic profile assessed in samples collected during the late cycle differently affected primary and secondary metabolisms and showed that most of the treatment-resulting variations occurred in opposite trends in inflorescences unbalanced in either hormonal or energy deficit abscission-inducing signals. Particularly concerning carbohydrates metabolism, sucrose, glucose, tricarboxylic acid metabolites and intermediates of the raffinose family oligosaccharides pathway were lower in shaded and higher in GAc samples. Altered oxidative stress remediation mechanisms and indolacetic acid (IAA) concentration were identified as abscission signatures common to both stimuli. According to the global analysis performed, we report that grape flower abscission mechanisms triggered by GAc application and C-starvation are not based on the same metabolic pathways. PMID:26157448

  15. Two divergent endo-beta-1,4-glucanase genes exhibit overlapping expression in ripening fruit and abscising flowers.

    PubMed Central

    Lashbrook, C C; Gonzalez-Bosch, C; Bennett, A B

    1994-01-01

    Two structurally divergent endo-beta-1,4-glucanase (EGase) cDNAs were cloned from tomato. Although both cDNAs (Cel1 and Cel2) encode potentially glycosylated, basic proteins of 51 to 53 kD and possess multiple amino acid domains conserved in both plant and microbial EGases, Cel1 and Cel2 exhibit only 50% amino acid identity at the overall sequence level. Amino acid sequence comparisons to other plant EGases indicate that tomato Cel1 is most similar to bean abscission zone EGase (68%), whereas Cel2 exhibits greatest sequence identity to avocado fruit EGase (57%). Sequence comparisons suggest the presence of at least two structurally divergent EGase families in plants. Unlike ripening avocado fruit and bean abscission zones in which a single EGase mRNA predominates, EGase expression in tomato reflects the overlapping accumulation of both Cel1 and Cel2 transcripts in ripening fruit and in plant organs undergoing cell separation. Cel1 mRNA contributes significantly to total EGase mRNA accumulation within plant organs undergoing cell separation (abscission zones and mature anthers), whereas Cel2 mRNA is most abundant in ripening fruit. The overlapping expression of divergent EGase genes within a single species may suggest that multiple activities are required for the cooperative disassembly of cell wall components during fruit ripening, floral abscission, and anther dehiscence. PMID:7994180

  16. CsPLDα1 and CsPLDγ1 are differentially induced during leaf and fruit abscission and diurnally regulated in Citrus sinensis

    PubMed Central

    Malladi, Anish; Burns, Jacqueline K.

    2008-01-01

    Understanding leaf and fruit abscission is essential in order to develop strategies for controlling the process in fruit crops. Mechanisms involved in signalling leaf and fruit abscission upon induction by abscission agents were investigated in Citrus sinensis cv. ‘Valencia’. Previous studies have suggested a role for phospholipid signalling; hence, two phospholipase D cDNA sequences, CsPLDα1 and CsPLDγ1, were isolated and their role was examined. CsPLDα1 expression was reduced in leaves but unaltered in fruit peel tissue treated with an ethylene-releasing compound (ethephon), or a fruit-specific abscission agent, 5-chloro-3-methyl-4-nitro-1H-pyrazole (CMNP). By contrast, CsPLDγ1 expression was up-regulated within 6 h (leaves) and 24 h (fruit peel) after treatment with ethephon or CMNP, respectively. CsPLDα1 expression was diurnally regulated in leaf blade but not fruit peel. CsPLDγ1 exhibited strong diurnal oscillation in expression in leaves and fruit peel with peak expression around midday. While diurnal fluctuation in CsPLDα1 expression appeared to be light-entrained in leaves, CsPLDγ1 expression was regulated by light and the circadian clock. The diurnal expression of both genes was modulated by ethylene-signalling. The ethephon-induced leaf abscission and the ethephon- and CMNP-induced decrease in fruit detachment force were enhanced by application during rising diurnal expression of CsPLDγ1. The results indicate differential regulation of CsPLDα1 and CsPLDγ1 in leaves and fruit, and suggest possible roles for PLD-dependent signalling in regulating abscission responses in citrus. PMID:18799715

  17. Pollination increases ethylene production in Lilium hybrida cv. Brindisi flowers but does not affect the time to tepal senescence or tepal abscission.

    PubMed

    Pacifici, Silvia; Prisa, Domenico; Burchi, Gianluca; van Doorn, Wouter G

    2015-01-15

    In many species, pollination induces a rapid increase in ethylene production, which induces early petal senescence, petal abscission, or flower closure. Cross-pollination in Lilium hybrida cv. Brindisi resulted in a small increase in flower ethylene production. In intact plants and in isolated flowers, pollination had no effect on the time to tepal senescence or tepal abscission. When applied to closed buds of unpollinated flowers, exogenous ethylene slightly hastened the time to tepal senescence and abscission. However, exogenous ethylene had no effect when the flowers had just opened, i.e. at the time of pollination. Experiments with silver thiosulphate, which blocks the ethylene receptor, indicated that endogenous ethylene had a slight effect on the regulation of tepal senescence and tepal abscission, although only at the time the tepals were still inside buds and not in open flowers. Low ethylene-sensitivity after anthesis therefore explains why pollination had no effect on the processes studied. Copyright © 2014 Elsevier GmbH. All rights reserved.

  18. Differential Behavior within a Grapevine Cluster: Decreased Ethylene-Related Gene Expression Dependent on Auxin Transport Is Correlated with Low Abscission of First Developed Berries

    PubMed Central

    Godoy, Francisca; Delrot, Serge; Arce-Johnson, Patricio

    2014-01-01

    In grapevine, fruit abscission is known to occur within the first two to three weeks after flowering, but the reason why some berries in a cluster persist and others abscise is not yet understood. Ethylene sensitivity modulates abscission in several fruit species, based on a mechanism where continuous polar auxin transport across the pedicel results in a decrease in ethylene perception, which prevents abscission. In grapevine, flowering takes about four to seven days in a single cluster, thus while some flowers are developing into berries, others are just starting to open. So, in this work it was assessed whether uneven flowering accounted for differences in berry abscission dependent on polar auxin transport and ethylene-related gene expression. For this, flowers that opened in a cluster were tagged daily, which allowed to separately analyze berries, regarding their ability to persist. It was found that berries derived from flowers that opened the day that flowering started – named as “first berries” – had lower abscission rate than berries derived from flowers that opened during the following days – named as “late berries”. Use of radiolabeled auxin showed that “first berries” had higher polar auxin transport, correlated with lower ethylene content and lower ethylene-related transcript abundance than “late berries”. When “first berries” were treated with a polar auxin transport inhibitor they showed higher ethylene-related transcript abundance and were more prone to abscise than control berries. This study provides new insights on fruit abscission control. Our results indicate that polar auxin transport sustains the ability of “first berries” to persist in the cluster during grapevine abscission and also suggest that this could be associated with changes in ethylene-related gene expression. PMID:25365421

  19. The ARF, AUX/IAA and GH3 gene families in citrus: genome-wide identification and expression analysis during fruitlet drop from abscission zone A.

    PubMed

    Xie, Rangjin; Pang, Shaoping; Ma, Yanyan; Deng, Lie; He, Shaolan; Yi, Shilai; Lv, Qiang; Zheng, Yongqiang

    2015-12-01

    Completion of the whole genome sequencing of citrus enabled us to perform genome-wide identification and functional analysis of the gene families involved in agronomic traits and morphological diversity of citrus. In this study, 22 CitARF, 11 CitGH3 and 26 CitAUX/IAA genes were identified in citrus, respectively. Phylogenetic analysis revealed that all the genes of each gene family could be subdivided into three groups and showed strong evolutionary conservation. The GH3 and AUX/IAA gene families shrank and ARF gene family was highly conserved in the citrus genome after speciation from Arabidopsis thaliana. Tissue-specific expression profiles revealed that 54 genes were expressed in at least one tissue while just 5 genes including CitARF07, CitARF20, CitGH3.04, CitAUX/IAA25 and CitAUX/IAA26 with very low expression level in all tissues tested, suggesting that the CitARF, CitGH3 and CitAUX/IAA gene families played important roles in the development of citrus organs. In addition, our data found that the expression of 2 CitARF, 4 CitGH3 and 4 AUX/IAA genes was affected by IAA treatment, and 7 genes including, CitGH3.04, CitGH3.07, CitAUX/IAA03, CitAUX/IAA04, CitAUX/IAA18, CitAUX/IAA19 and CitAUX/IAA23 were related to fruitlet abscission. This study provides a foundation for future studies on elucidating the precise role of citrus ARF, GH3 and AUX/IAA genes in early steps of auxin signal transduction and open up a new opportunity to uncover the molecular mechanism underlying citrus fruitlet abscission.

  20. Effect of raceme-localized supplemental light on soybean reproductive abscission

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

    Myers, R.L.; Brun, W.A.; Brenner, M.L.

    The percentage of soybean (Glycine max (L.) Merr.) reproductive structures that abscise is a potentially important yield factor. To better understand the involvement of light in the abscission of reproductive structures, a series of in vitro raceme-culture and growth-chamber experiments were conducted. In the in vitro raceme-culture experiments, racemes with four to six flowers at or past anthesis were excised from the soybean plant (genotype IX93-100), embedded in a complete nutrient, solid agar medium, and subjected to various light treatments. A series of three experiments indicated that the racemes contain a photoreceptor, possibly phytochrome, capable of regulating sucrose accumulation. Inmore » each of the growth chamber studies, supplemental light was supplied directly to individual soybean flowers via fiber optic light guides. The light source increased the photon flux to the flowers by 10-fold. The first growth chamber experiment showed that flowers receiving supplemental light were more intense sinks for /sup 14/C-sucrose than were controls (intensity value of 1.0 vs 0.4 x 10/sup -7/, intensity = (dps of flower/dps of raceme)/(kg dry wt of flower)). In a second study, 42% of flowers treated with supplemental light set pods, while only 26% of control flowers set pods. A third experiment showed that red supplemental light produced 55% fruit set, compared to 41% set for far-red light, and 35% for controls. These experiments indicate that both photoassimilate accumulation and abscission in young soybean reproductive structures may be regulated by light quality.« less

  1. Free-zone electrophoresis of animal cells. 1: Experiments on cell-cell interactions

    NASA Technical Reports Server (NTRS)

    Todd, P. W.; Hjerten, S.

    1985-01-01

    The electrophoretically migrating zones wasa monitored. The absence of fluid flows in the direction of migration permits direct measurement of electrophoretic velocities of any material. Sedimentation is orthogonal to electrokinetic motion and the effects of particle-particle interaction on electrophoretic mobility is studied by free zone electrophoresis. Fixed erythrocytes at high concentrations, mixtures of fixed erythrocytes from different animal species, and mixtures of cultured human cells were studied in low ionic strength buffers. The electrophoretic velocity of fixed erythrocytes was not altered by increasing cell concentration or by the mixing of erythrocytes from different species. When zones containing cultured human glial cells and neuroblastoma cells are permitted to interact during electrophoresis, altered migration patterns occur. It is found that cell-cell interactions depends upon cell type.

  2. Conservation of the abscission signaling peptide IDA during Angiosperm evolution: withstanding genome duplications and gain and loss of the receptors HAE/HSL2

    PubMed Central

    Stø, Ida M.; Orr, Russell J. S.; Fooyontphanich, Kim; Jin, Xu; Knutsen, Jonfinn M. B.; Fischer, Urs; Tranbarger, Timothy J.; Nordal, Inger; Aalen, Reidunn B.

    2015-01-01

    The peptide INFLORESCENCE DEFICIENT IN ABSCISSION (IDA), which signals through the leucine-rich repeat receptor-like kinases HAESA (HAE) and HAESA-LIKE2 (HSL2), controls different cell separation events in Arabidopsis thaliana. We hypothesize the involvement of this signaling module in abscission processes in other plant species even though they may shed other organs than A. thaliana. As the first step toward testing this hypothesis from an evolutionarily perspective we have identified genes encoding putative orthologs of IDA and its receptors by BLAST searches of publically available protein, nucleotide and genome databases for angiosperms. Genes encoding IDA or IDA-LIKE (IDL) peptides and HSL proteins were found in all investigated species, which were selected as to represent each angiosperm order with available genomic sequences. The 12 amino acids representing the bioactive peptide in A. thaliana have virtually been unchanged throughout the evolution of the angiosperms; however, the number of IDL and HSL genes varies between different orders and species. The phylogenetic analyses suggest that IDA, HSL2, and the related HSL1 gene, were present in the species that gave rise to the angiosperms. HAE has arisen from HSL1 after a genome duplication that took place after the monocot—eudicots split. HSL1 has also independently been duplicated in the monocots, while HSL2 has been lost in gingers (Zingiberales) and grasses (Poales). IDA has been duplicated in eudicots to give rise to functionally divergent IDL peptides. We postulate that the high number of IDL homologs present in the core eudicots is a result of multiple whole genome duplications (WGD). We substantiate the involvement of IDA and HAE/HSL2 homologs in abscission by providing gene expression data of different organ separation events from various species. PMID:26579174

  3. Ethylene: role in fruit abscission and dehiscence processes.

    PubMed

    Lipe, J A; Morgan, P W

    1972-12-01

    Two peaks of ethylene production occur during the development of cotton fruitz (Gossypium hirsutum L.). These periods precede the occurrence of young fruit shedding and mature fruit dehiscence, both of which are abscission phenomena and the latter is generally assumed to be part of the total ripening process. Detailed study of the dehiscence process revealed that ethylene production of individual, attached cotton fruits goes through a rising, cyclic pattern which reaches a maximum prior to dehiscence. With detached pecan fruits (Carya illinoensis [Wang.] K. Koch), ethylene production measured on alternate days rose above 1 microliter per kilogram fresh weight per hour before dehiscence began and reached a peak several days prior to complete dehiscence. Ethylene production by cotton and pecan fruits was measured just prior to dehiscence and then the internal concentration of the gas near the center of the fruit was determined. From these data a ratio of production rate to internal concentration was determined which allowed calculation of the approximate ethylene concentration in the intact fruit prior to dehiscence and selection of appropriate levels to apply to fruits. Ethylene at 10 microliters per liter of air appears to saturate dehiscence of cotton, pecan, and okra (Hibiscus esculentus L.) fruits and the process is completed in 3 to 4 days. In all cases some hastening of dehiscence was observed with as little as 0.1 microliter of exogenous ethylene per liter of air. The time required for response to different levels of ethylene was determined and compared to the time course of ethylene production and dehiscence. We concluded that internal levels of ethylene rose to dehiscence-stimulating levels a sufficience time before dehiscence for the gas to have initiated the process. Since our data and calculations indicate that enough ethylene is made a sufficient time before dehiscence, to account for the process, we propose that ethylene is one of the regulators of

  4. Motor activity of centromere-associated protein-E contributes to its localization at the center of the midbody to regulate cytokinetic abscission

    PubMed Central

    Ohashi, Akihiro; Ohori, Momoko; Iwai, Kenichi

    2016-01-01

    Accurate control of cytokinesis is critical for genomic stability to complete high-fidelity transmission of genetic material to the next generation. A number of proteins accumulate in the intercellular bridge (midbody) during cytokinesis, and the dynamics of these proteins are temporally and spatially orchestrated to complete the process. In this study, we demonstrated that localization of centromere-associated protein-E (CENP-E) at the midbody is involved in cytokinetic abscission. The motor activity of CENP-E and the C-terminal midbody localization domain, which includes amino acids 2659–2666 (RYFDNSSL), are involved in the anchoring of CENP-E to the center of the midbody. Furthermore, CENP-E motor activity contributes to the accumulation of protein regulator of cytokinesis 1 (PRC1) in the midbody during cytokinesis. Midbody localization of PRC1 is critical to the antiparallel microtubule structure and recruitment of other midbody-associated proteins. Therefore, CENP-E motor activity appears to play important roles in the organization of these proteins to complete cytokinetic abscission. Our findings will be helpful for understanding how each step of cytokinesis is regulated to complete cytokinetic abscission. PMID:27835888

  5. Leaf shedding as an anti-bacterial defense in Arabidopsis cauline leaves

    PubMed Central

    2017-01-01

    Plants utilize an innate immune system to protect themselves from disease. While many molecular components of plant innate immunity resemble the innate immunity of animals, plants also have evolved a number of truly unique defense mechanisms, particularly at the physiological level. Plant’s flexible developmental program allows them the unique ability to simply produce new organs as needed, affording them the ability to replace damaged organs. Here we develop a system to study pathogen-triggered leaf abscission in Arabidopsis. Cauline leaves infected with the bacterial pathogen Pseudomonas syringae abscise as part of the defense mechanism. Pseudomonas syringae lacking a functional type III secretion system fail to elicit an abscission response, suggesting that the abscission response is a novel form of immunity triggered by effectors. HAESA/HAESA-like 2, INFLORESCENCE DEFICIENT IN ABSCISSION, and NEVERSHED are all required for pathogen-triggered abscission to occur. Additionally phytoalexin deficient 4, enhanced disease susceptibility 1, salicylic acid induction-deficient 2, and senescence-associated gene 101 plants with mutations in genes necessary for bacterial defense and salicylic acid signaling, and NahG transgenic plants with low levels of salicylic acid fail to abscise cauline leaves normally. Bacteria that physically contact abscission zones trigger a strong abscission response; however, long-distance signals are also sent from distal infected tissue to the abscission zone, alerting the abscission zone of looming danger. We propose a threshold model regulating cauline leaf defense where minor infections are handled by limiting bacterial growth, but when an infection is deemed out of control, cauline leaves are shed. Together with previous results, our findings suggest that salicylic acid may regulate both pathogen- and drought-triggered leaf abscission. PMID:29253890

  6. Modification of carotenoid levels by abscission agents and expression of carotenoid biosynthetic genes in 'valencia' sweet orange.

    PubMed

    Alferez, Fernando; Pozo, Luis V; Rouseff, Russell R; Burns, Jacqueline K

    2013-03-27

    The effect of 5-chloro-3-methyl-4-nitro-1H-pyrazole (CMNP) and ethephon on peel color, flavedo carotenoid gene expression, and carotenoid accumulation was investigated in mature 'Valencia' orange ( Citrus sinensis L. Osbeck) fruit flavedo at three maturation stages. Abscission agent application altered peel color. CMNP was more effective than ethephon in promoting green-to-red (a) and blue-to-yellow (b) color at the middle and late maturation stages and total carotenoid changes at all maturation stages. Altered flow of carotenoid precursors during maturation due to abscission agents was suggested by changes in phytoene desaturase (Pds) and ζ-carotene desaturase (Zds) gene expression. However, each abscission agent affected downstream expression differentially. Ethephon application increased β-carotene hydroxilase (β-Chx) transcript accumulation 12-fold as maturation advanced from the early to middle and late stages. CMNP markedly increased β- and ε-lycopene cyclase (Lcy) transcript accumulation 45- and 15-fold, respectively, at midmaturation. Patterns of carotenoid accumulation in flavedo were supported in part by gene expression changes. CMNP caused greater accumulation of total flavedo carotenoids at all maturation stages when compared with ethephon or controls. In general, CMNP treatment increased total red carotenoids more than ethephon or the control but decreased total yellow carotenoids at each maturation stage. In control fruit flavedo, total red carotenoids increased and yellow carotenoids decreased as maturation progressed. Trends in total red carotenoids during maturation were consistent with measured a values. Changes in carotenoid accumulation and expression patterns in flavedo suggest that regulation of carotenoid accumulation is under transcriptional, translational, and post-translational control.

  7. Ethylene: Role in Fruit Abscission and Dehiscence Processes 12

    PubMed Central

    Lipe, John A.; Morgan, Page W.

    1972-01-01

    Two peaks of ethylene production occur during the development of cotton fruitz (Gossypium hirsutum L.). These periods precede the occurrence of young fruit shedding and mature fruit dehiscence, both of which are abscission phenomena and the latter is generally assumed to be part of the total ripening process. Detailed study of the dehiscence process revealed that ethylene production of individual, attached cotton fruits goes through a rising, cyclic pattern which reaches a maximum prior to dehiscence. With detached pecan fruits (Carya illinoensis [Wang.] K. Koch), ethylene production measured on alternate days rose above 1 microliter per kilogram fresh weight per hour before dehiscence began and reached a peak several days prior to complete dehiscence. Ethylene production by cotton and pecan fruits was measured just prior to dehiscence and then the internal concentration of the gas near the center of the fruit was determined. From these data a ratio of production rate to internal concentration was determined which allowed calculation of the approximate ethylene concentration in the intact fruit prior to dehiscence and selection of appropriate levels to apply to fruits. Ethylene at 10 microliters per liter of air appears to saturate dehiscence of cotton, pecan, and okra (Hibiscus esculentus L.) fruits and the process is completed in 3 to 4 days. In all cases some hastening of dehiscence was observed with as little as 0.1 microliter of exogenous ethylene per liter of air. The time required for response to different levels of ethylene was determined and compared to the time course of ethylene production and dehiscence. We concluded that internal levels of ethylene rose to dehiscence-stimulating levels a sufficience time before dehiscence for the gas to have initiated the process. Since our data and calculations indicate that enough ethylene is made a sufficient time before dehiscence, to account for the process, we propose that ethylene is one of the regulators of

  8. Changes in growth, leaf abscission, and biomass associated with seasonal tropospheric ozone exposures of Populus tremuloides clones and seedlings

    Treesearch

    D.F. Karnosky; Z.E. Gagnon; R.E. Dickson; M.D. Coleman; E.H. Lee; J.G. Isebrands

    1996-01-01

    The effects of single-season tropospheric ozone (03) exposures on growth, leaf abscission, and biomass of trembling aspen (Populus tremuloides Michx.) rooted cuttings and seedlings were studied. Plants were grown in the Upper Peninsula of Michigan in open-top chambers with 03 exposures that ranged from...

  9. Transition zone cells reach G2 phase before initiating elongation in maize root apex

    PubMed Central

    Alarcón, M. Victoria

    2017-01-01

    ABSTRACT Root elongation requires cell divisions in the meristematic zone and cell elongation in the elongation zone. The boundary between dividing and elongating cells is called the transition zone. In the meristem zone, initial cells are continuously dividing, but on the basal side of the meristem cells exit the meristem through the transition zone and enter in the elongation zone, where they stop division and rapidly elongate. Throughout this journey cells are accompanied by changes in cell cycle progression. Flow cytometry analysis showed that meristematic cells are in cycle, but exit when they enter the elongation zone. In addition, the percentage of cells in G2 phase (4C) strongly increased from the meristem to the elongation zone. However, we did not observe remarkable changes in the percentage of cells in cell cycle phases along the entire elongation zone. These results suggest that meristematic cells in maize root apex stop the cell cycle in G2 phase after leaving the meristem. PMID:28495964

  10. A Jasmonate ZIM-Domain Protein NaJAZd Regulates Floral Jasmonic Acid Levels and Counteracts Flower Abscission in Nicotiana attenuata Plants

    PubMed Central

    Oh, Youngjoo; Baldwin, Ian T.; Galis, Ivan

    2013-01-01

    Jasmonic acid is an important regulator of plant growth, development and defense. The jasmonate-ZIM domain (JAZ) proteins are key regulators in jasmonate signaling ubiquitously present in flowering plants but their functional annotation remains largely incomplete. Recently, we identified 12 putative JAZ proteins in native tobacco, Nicotiana attenuata, and initiated systematic functional characterization of these proteins by reverse genetic approaches. In this report, Nicotiana attenuata plants silenced in the expression of NaJAZd (irJAZd) by RNA interference were used to characterize NaJAZd function. Although NaJAZd transcripts were strongly and transiently up-regulated in the rosette leaves by simulated herbivory treatment, we did not observe strong defense-related phenotypes, such as altered herbivore performance or the constitutive accumulation of defense-related secondary metabolites in irJAZd plants compared to wild type plants, both in the glasshouse and the native habitat of Nicotiana attenuata in the Great Basin Desert, Utah, USA. Interestingly, irJAZd plants produced fewer seed capsules than did wild type plants as a result of increased flower abscission in later stages of flower development. The early- and mid-developmental stages of irJAZd flowers had reduced levels of jasmonic acid and jasmonoyl-L-isoleucine, while fully open flowers had normal levels, but these were impaired in NaMYB305 transcript accumulations. Previously, NaMYB305-silenced plants were shown to have strong flower abscission phenotypes and contained lower NECTARIN 1 transcript levels, phenotypes which are copied in irJAZd plants. We propose that the NaJAZd protein is required to counteract flower abscission, possibly by regulating jasmonic acid and jasmonoyl-L-isoleucine levels and/or expression of NaMYB305 gene in Nicotiana attenuata flowers. This novel insight into the function of JAZ proteins in flower and seed development highlights the diversity of functions played by jasmonates

  11. Extranodal Marginal Zone B-cell Lymphoma of the Ocular Adnexa.

    PubMed

    Guffey Johnson, Jean; Terpak, Lauren A; Margo, Curtis E; Setoodeh, Reza

    2016-04-01

    Low-grade B-cell lymphomas located around the eye present unique challenges in diagnosis and treatment. Extranodal marginal zone B-cell lymphoma is the most common lymphoma of the ocular adnexa (conjunctiva, orbit, lacrimal gland, and eyelid). A systematic search of the relevant literature was performed. Material pertinent to the diagnosis, prognosis, pathogenesis, and treatment of extranodal marginal zone B-cell lymphoma of the ocular adnexa was identified, reviewed, and analyzed, focusing on management strategies for primary localized disease. The primary cause of extranodal marginal zone B-cell lymphoma of the ocular adnexa remains elusive, although an infectious agent is suspected. Radiotherapy is the most common initial treatment for localized disease. Initial treatment with chemotherapy, immunotherapy, and antibiotics has shown promising results, but the number of series is limited and controlled trials do not exist. Although the long-term outcome of localized extranodal marginal zone B-cell lymphoma of the ocular adnexa is good, optimal treatment remains a goal. The variation in rates of local and systemic relapse among treated stage 1E tumors suggests that critical factors affecting outcomes are not fully understood. Radiotherapy is the standard of care; at this time, the evidence is insufficient to recommend chemotherapy, immunotherapy, or antibiotics for initial treatment of extranodal marginal zone B-cell lymphoma localized to the ocular adnexa. Well-controlled comparative studies are needed.

  12. Are we on the right track: Can our understanding of abscission in model systems promote or derail making improvements in less studied crops

    USDA-ARS?s Scientific Manuscript database

    As the world population grows and resources and climate conditions change, crop improvement continues to be one of the most important challenges for agriculturalists. The yield and quality of many crops is affected by abscission or shattering, and environmental stresses often hasten or alter the abs...

  13. Small cell lymphocytic variant of marginal zone lymphoma: A distinct form of marginal zone lymphoma derived from naïve B cells as a cutaneous counterpart to the naïve marginal zone lymphoma of splenic origin.

    PubMed

    Magro, Cynthia M; Olson, Luke C

    2018-02-21

    Primary cutaneous marginal zone lymphoma most commonly represents an indolent form of cutaneous B cell lymphoma. However, epidermotropic marginal zone lymphoma, blastic marginal zone lymphoma and B cell dominant variants without isotype switching can be associated with extracutaneous dissemination. The presumptive cell of origin is a post germinal center B cell with plasmacytic features. In the extracutaneous setting, however, a naïve B cell origin has been proposed for a subset of marginal zone lymphomas, notably splenic marginal zone lymphoma. The author encountered 11 cases of atypical lymphocytic infiltration of the skin primarily occurring in older individuals with an upper arm and head and neck localization; there was a reproducible pattern of diffuse and nodular infiltration by small monomorphic-appearing B cells. Phenotypically, the infiltrate was one predominated by B cells exhibiting CD23 and IgD positivity without immunoreactivity for CD38 and there were either no plasma cells or only a few without light chain restriction. In cases presenting with a solitary lesion complete excision and/or radiation led to successful disease remission in all cases without recurrence or metastatic disease. Of three cases with multiple initial lesions, evidence of extracutaneous disease was seen in two cases and recurrence occurred in one case. No patients have died of lymphoma. Longer term follows up and additional cases are needed to determine if this subset of marginal zone lymphoma is associated with a worse prognosis. Copyright © 2018. Published by Elsevier Inc.

  14. Langerhans cell sarcoma following marginal zone lymphoma: expanding the knowledge on mature B cell plasticity.

    PubMed

    Ambrosio, Maria Raffaella; De Falco, Giulia; Rocca, Bruno Jim; Barone, Aurora; Amato, Teresa; Bellan, Cristiana; Lazzi, Stefano; Leoncini, Lorenzo

    2015-10-01

    The concept of unidirectional differentiation of the haematopoietic stem cell has been challenged after recent findings that human B cell progenitors and even mature B cells can be reprogrammed into histiocytic/dendritic cells by altering expression of lineage-associated transcription factors. The conversion of mature B cell lymphomas to Langerhans cell neoplasms is not well documented. Three previous reports have described clonally related follicular lymphoma and Langerhans cell tumours, whereas no case has been published of clonally related marginal zone lymphoma and Langerhans cell sarcoma. We describe the case of a 77-year-old patient who developed a Langerhans cell sarcoma and 6 years later a nodal marginal zone lymphoma. Mutation status examination showed 100 % gene identity to the germline sequence, suggesting direct trans-differentiation or dedifferentiation of the nodal marginal zone lymphoma to the Langerhans cell sarcoma rather than a common progenitor. We found inactivation of paired box 5 (PAX-5) in the lymphoma cells by methylation, along with duplication of part of the long arm of chromosomes 16 and 17 in the sarcoma cells. The absence of PAX-5 could have triggered B cells to differentiate into macrophages and dendritic cells. On the other hand, chromosomal imbalances might have activated genes involved in myeloid lineage maturation, transcription activation and oncogenesis. We hypothesize that this occurred because of previous therapies for nodal marginal zone lymphoma. Better understanding of this phenomenon may help in unravelling the molecular interplay between transcription factors during haematopoietic lineage commitment and may expand the spectrum of clonally related mature B cell neoplasms and Langerhans cell tumours.

  15. Are We on the Right Track: Can Our Understanding of Abscission in Model Systems Promote or Derail Making Improvements in Less Studied Crops?

    PubMed Central

    Patterson, Sara E.; Bolivar-Medina, Jenny L.; Falbel, Tanya G.; Hedtcke, Janet L.; Nevarez-McBride, Danielle; Maule, Andrew F.; Zalapa, Juan E.

    2016-01-01

    As the world population grows and resources and climate conditions change, crop improvement continues to be one of the most important challenges for agriculturalists. The yield and quality of many crops is affected by abscission or shattering, and environmental stresses often hasten or alter the abscission process. Understanding this process can not only lead to genetic improvement, but also changes in cultural practices and management that will contribute to higher yields, improved quality and greater sustainability. As plant scientists, we have learned significant amounts about this process through the study of model plants such as Arabidopsis, tomato, rice, and maize. While these model systems have provided significant valuable information, we are sometimes challenged to use this knowledge effectively as variables including the economic value of the crop, the uniformity of the crop, ploidy levels, flowering and crossing mechanisms, ethylene responses, cultural requirements, responses to changes in environment, and cellular and tissue specific morphological differences can significantly influence outcomes. The value of genomic resources for lesser-studied crops such as cranberries and grapes and the orphan crop fonio will also be considered. PMID:26858730

  16. Are We on the Right Track: Can Our Understanding of Abscission in Model Systems Promote or Derail Making Improvements in Less Studied Crops?

    PubMed

    Patterson, Sara E; Bolivar-Medina, Jenny L; Falbel, Tanya G; Hedtcke, Janet L; Nevarez-McBride, Danielle; Maule, Andrew F; Zalapa, Juan E

    2015-01-01

    As the world population grows and resources and climate conditions change, crop improvement continues to be one of the most important challenges for agriculturalists. The yield and quality of many crops is affected by abscission or shattering, and environmental stresses often hasten or alter the abscission process. Understanding this process can not only lead to genetic improvement, but also changes in cultural practices and management that will contribute to higher yields, improved quality and greater sustainability. As plant scientists, we have learned significant amounts about this process through the study of model plants such as Arabidopsis, tomato, rice, and maize. While these model systems have provided significant valuable information, we are sometimes challenged to use this knowledge effectively as variables including the economic value of the crop, the uniformity of the crop, ploidy levels, flowering and crossing mechanisms, ethylene responses, cultural requirements, responses to changes in environment, and cellular and tissue specific morphological differences can significantly influence outcomes. The value of genomic resources for lesser-studied crops such as cranberries and grapes and the orphan crop fonio will also be considered.

  17. Primary cutaneous marginal zone B-cell lymphoma: clinical and histological aspects.

    PubMed

    Khaled, A; Sassi, S; Fazaa, B; Ben Hassouna, J; Ben Romdhane, K; Kamoun, M R

    2009-02-01

    According to the WHO-EORTC classification of cutaneous lymphomas, primary cutaneous marginal zone B-cell lymphoma are now well characterized. We report here a case of primary cutaneous marginal zone B-cell lymphoma in a 51 year-old man in which the diagnosis was made using both histology and immunopathology. The patient had no remarkable medical history, no history of either acute inflammation or insect bite, and presented with a 5 cm solitary asymptomatic erythematous firm, multinodular and infiltrated plaque on the back for 12 months. Histological examination and immunohistochemical study of a cutaneous biopsy provided a differential diagnosis between B cell lymphoma and lymphocytoma cutis. Full body work up revealed no signs of extracutaneous dissemination. The patient underwent surgical excision of the nodule. Histological examination showed a histological and immunophenotyping profile typical of primary cutaneous marginal zone B-cell lymphoma. The lesion was completely excised with clear margins and no recurrence occurred after a 12 month-follow-up period. Primary cutaneous marginal zone B-cell lymphoma are low-grade lymphomas that have an indolent course and a high tendency to recur. They should be differentiated from lymphocytoma cutis and from the other types of cutaneous B cell lymphomas that have a different course and prognosis.

  18. Sca-1(+) mesenchymal stromal cells inhibit splenic marginal zone B lymphocytes commitment through Caspase-3.

    PubMed

    Chen, Yaozhen; Yang, Jialei; Zhang, Hui-Jie; Fan, Hong; An, Ning; Xin, Jiajia; Li, Na; Xu, Jinmei; Yin, Wen; Wu, Zhongliang; Hu, Xingbin

    2016-05-01

    Mesenchymal stromal cells (MSCs) have been characterized as an important component of hematopoietic niche, which are capable of modulating the immune system through interaction with a wide range of immune cells. Marginal zone B cells, one main type of mature B lymphocytes, play a central role in eliciting antibody response against pathogens. However, how MSCs and its subpopulations regulate marginal zone B cells commitment is unknown yet. In this study, we assessed the contribution of Sca-1(+) MSCs on marginal zone B cells commitment. Our results showed that Sca-1(+) MSCs inhibit the commitment of marginal zone B lymphocytes. The inhibition was exerted through lowered Caspase-3 expression. Furthermore, we found marginal zone B lymphocytes in spleen of Caspase-3 knockout mice decreased and Caspase-3 knockout Sca-1(+) MSCs accounted for the MZB lymphocytes decrease. In conclusion, our investigation provided clues about Sca-1(+) MSCs regulation on the commitment of marginal zone B cells through Caspase-3 gene. © 2016 International Federation for Cell Biology.

  19. Identifying Developmental Zones in Maize Lateral Root Cell Length Profiles using Multiple Change-Point Models

    PubMed Central

    Moreno-Ortega, Beatriz; Fort, Guillaume; Muller, Bertrand; Guédon, Yann

    2017-01-01

    The identification of the limits between the cell division, elongation and mature zones in the root apex is still a matter of controversy when methods based on cellular features, molecular markers or kinematics are compared while methods based on cell length profiles have been comparatively underexplored. Segmentation models were developed to identify developmental zones within a root apex on the basis of epidermal cell length profiles. Heteroscedastic piecewise linear models were estimated for maize lateral roots of various lengths of both wild type and two mutants affected in auxin signaling (rtcs and rum-1). The outputs of these individual root analyses combined with morphological features (first root hair position and root diameter) were then globally analyzed using principal component analysis. Three zones corresponding to the division zone, the elongation zone and the mature zone were identified in most lateral roots while division zone and sometimes elongation zone were missing in arrested roots. Our results are consistent with an auxin-dependent coordination between cell flux, cell elongation and cell differentiation. The proposed segmentation models could extend our knowledge of developmental regulations in longitudinally organized plant organs such as roots, monocot leaves or internodes. PMID:29123533

  20. Citrus Tissue Culture 1

    PubMed Central

    Einset, John W.; Lyon, J. Lorene; Sipes, Deborah L.

    1981-01-01

    An in vitro bioassay for chemicals that affect Citrus abscission was used to identify three inhibitors of stylar abscission in lemon pistil explants incubated on defined nutrient media. The three inhibitors (picloram, 4-chlorophenoxyacetic acid, and 3,5,6-trichloropyridine-2-oxyacetic acid) are all auxins, and the most potent of them (i.e. picloram) was found to be at least 10 times more active in the bioassay than 2,4-dichlorophenoxyacetic acid. Picloram (2 micromolar) also was shown to be effective in inhibiting stylar abscission in pistil explants from other Citrus cultivars such as mandarin, Valencia, and Washington navel oranges and grapefruit. To study the physiology of auxins active as abscission inhibitors versus inactive auxins in lemon pistils, the transport and metabolism of [1-14C]-2,4-dichlorophenoxyacetic acid was compared with that of [2-14C]indole-3-acetic acid, which is without effect in the bioassay over the range from 0.1-100 micromolar. Insignificant quantities of labeled indole-3-acetic acid and/or labeled derivatives were found to reach the presumptive zone of stylar abscission under the test conditions. Labeled 2,4-dichlorophenoxyacetic acid and/or labeled derivatives also were transported slowly through pistils, but some radioactivity could be detected in the stylar abscission zone as early as 24 hours after the start of incubation. Extensive conversion of [2-14C]indole-3-acetic acid to labeled compounds tentatively considered to be glycoside and cellulosic glucan derivatives was found with the use of solvent extraction methodology. A significantly smaller percentage of the radioactivity in pistils incubated on [1-14C]-2,4-dichlorophenoxyacetic acid was found in fractions corresponding to these derivatives. Both transport and metabolism appear to be important factors affecting the activity of auxins as abscission inhibitors in the bioassay. PMID:16661819

  1. Root Apex Transition Zone As Oscillatory Zone

    PubMed Central

    Baluška, František; Mancuso, Stefano

    2013-01-01

    Root apex of higher plants shows very high sensitivity to environmental stimuli. The root cap acts as the most prominent plant sensory organ; sensing diverse physical parameters such as gravity, light, humidity, oxygen, and critical inorganic nutrients. However, the motoric responses to these stimuli are accomplished in the elongation region. This spatial discrepancy was solved when we have discovered and characterized the transition zone which is interpolated between the apical meristem and the subapical elongation zone. Cells of this zone are very active in the cytoskeletal rearrangements, endocytosis and endocytic vesicle recycling, as well as in electric activities. Here we discuss the oscillatory nature of the transition zone which, together with several other features of this zone, suggest that it acts as some kind of command center. In accordance with the early proposal of Charles and Francis Darwin, cells of this root zone receive sensory information from the root cap and instruct the motoric responses of cells in the elongation zone. PMID:24106493

  2. Involvement of abscisic acid in correlative control of flower abscission in soybean

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

    Yarrow, G.L.

    1985-01-01

    Studies were carried out in three parts: (1) analysis of endogenous abscisic acid (ABA) in abscising and non-abscising flowers, (2) partitioning of radio-labelled ABA and photoassimilates within the soybean raceme, and (3) shading experiments, wherein endogenous levels, metabolism and partitioning of ABA were determined. Endogenous concentrations of ABA failed to show any consistent relationship to abscission of soybean flowers. Partitioning of radiolabelled ABA and photoassimilates displayed consistently higher sink strengths (% DPM) for both /sup 3/H-ABA and /sup 14/C-photoassimilates for non-abscising flowers than for abscising flowers within control racemes. Shading flowers with aluminum foil, 48 hrs prior to sampling, resultedmore » in lowered endogenous ABA concentrations at 12, 17 and 22 days after anthesis (DAA), but not at 0 or 4 DAA. No differences were found in the catabolism of /sup 3/H-ABA between shaded (abscising) and non-shaded (non-abscising) flowers. Reduced partitioning of ABA and photoassimilates to shaded flowers resulted when shades were applied at 0, 4, 12, and 17 DAA, but not at 22 DAA.« less

  3. The development of primary and secondary lymphoid tissues in the nurse shark Ginglymostoma cirratum: B-cell zones precede dendritic cell immigration and T-cell zone formation during ontogeny of the spleen.

    PubMed

    Rumfelt, L L; McKinney, E C; Taylor, E; Flajnik, M F

    2002-08-01

    Secondary lymphoid tissue and immunoglobulin (Ig) production in mammals is not fully developed at birth, requiring time postnatally to attain all features required for adaptive immune responses. The immune system of newborn sharks - the oldest vertebrate group having adaptive immunity - also displays immature characteristics such as low serum IgM concentration and high levels of IgM1gj, an innate-like Ig. Primary and secondary lymphoid tissues in sharks and other cartilaginous fish were identified previously, but their cellular organization was not examined in detail. In this study of nurse shark lymphoid tissue, we demonstrate that the adult spleen contains well-defined, highly vascularized white pulp (WP) areas, composed of a central T-cell zone containing a major histocompatibility complex (MHC) class II+ dendritic cell (DC) network and a small number of Ig+ secretory cells, surrounded by smaller zones of surface Ig+ (sIg+) B cells. In neonates, splenic WPs are exclusively B-cell zones containing sIgM+-MHC class IIlow B cells; thus compartmentalized areas with T cells and DCs, as well as surface Ig novel antigen receptor (sIgNAR)-expressing B cells are absent at birth. Not until the pups are 5 months old do these WP areas become adult-like; concomitantly, sIgNAR+ B cells are readily detectable, indicating that this Ig class requires a 'mature immune-responsive environment'. The epigonal organ is the major site of neonatal B lymphopoiesis, based on the presence of developing B cells and recombination-activating gene 1 (RAG1)/terminal deoxynucleotidyl transferase (TdT) expression, indicative of antigen receptor rearrangement; such expression persists into adult life, whereas the spleen has negligible lymphopoietic activity. In adults but not neonates, many secretory B cells reside in the epigonal organ, suggesting, like in mammals, that B cells home to this primary lymphoid tissue after activation in other areas of the body.

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

    Cohen, Michael F.; Gurung, Sushma; Birarda, Giovanni

    In the genus Azolla rapid abscission of roots from floating fronds occurs within minutes in response to a variety of stresses, including exposure to nitrite. We found that hydrogen peroxide, though itself not an inducer of root abscission, modulates nitrite-induced root abscission by Azolla pinnata in a dose-dependent manner, with 2 mM H 2O 2 significantly diminishing the responsiveness to 2 mM NaNO 2, and 10 mM H 2O 2 slightly enhancing it. Hypoxia, which has been found in other plants to result in autogenic production of H 2O 2, dramatically stimulated root abscission of A. pinnata in response tomore » nitrite, especially for plants previously cultivated in medium containing 5 mM KNO 3 compared to plants cultivated under N 2-fixing conditions without combined nitrogen. Plants, including Azolla, produce the small signaling molecule nitric oxide (NO) from nitrite using nitrate reductase. We found Azolla plants to display dose-dependent root abscission in response to the NO donor spermine NONOate. Treatment of plants with the thiol-modifying agents S-methyl methanethiosulfonate or glutathione inhibited the nitrite-induced root abscission response. Synchrotron radiation-based Fourier transform infrared spectromicroscopy revealed higher levels of carbonylation in the abscission zone of dropped roots, indicative of reaction products of polysaccharides with potent free radical oxidants. Lastly, we hypothesize that metabolic products of nitrite and NO react with H 2O 2 in the apoplast leading to free-radical-mediated cleavage of structural polysaccharides and consequent rapid root abscission.« less

  5. Additional Amphivasal Bundles in Pedicel Pith Exacerbate Central Fruit Dominance and Induce Self-Thinning of Lateral Fruitlets in Apple1[C][W

    PubMed Central

    Celton, Jean-Marc; Dheilly, Emmanuelle; Guillou, Marie-Charlotte; Simonneau, Fabienne; Juchaux, Marjorie; Costes, Evelyne; Laurens, François; Renou, Jean-Pierre

    2014-01-01

    Apple (Malus × domestica) trees naturally produce an excess of fruitlets that negatively affect the commercial value of fruits brought to maturity and impact their capacity to develop flower buds the following season. Therefore, chemical thinning has become an important cultural practice, allowing the selective removal of unwanted fruitlets. As the public pressure to limit the use of chemical agents increases, the control of thinning becomes a major issue. Here, we characterized the self-thinning capacity of an apple hybrid genotype from the tree scale to the molecular level. Additional amphivasal vascular bundles were identified in the pith of pedicels supporting the fruitlets with the lowest abscission potential (central fruitlet), indicating that these bundles might have a role in the acquisition of dominance over lateral fruitlets. Sugar content analysis revealed that central fruitlets were better supplied in sorbitol than lateral fruitlets. Transcriptomic profiles allowed us to identify genes potentially involved in the overproduction of vascular tissues in central pedicels. In addition, histological and transcriptomic data permitted a detailed characterization of abscission zone development and the identification of key genes involved in this process. Our data confirm the major role of ethylene, auxin, and cell wall-remodeling enzymes in abscission zone formation. The shedding process in this hybrid appears to be triggered by a naturally exacerbated dominance of central fruitlets over lateral ones, brought about by an increased supply of sugars, possibly through additional amphivasal vascular bundles. The characterization of this genotype opens new perspectives for the selection of elite apple cultivars. PMID:24550240

  6. Stem cells in Nanomia bijuga (Siphonophora), a colonial animal with localized growth zones.

    PubMed

    Siebert, Stefan; Goetz, Freya E; Church, Samuel H; Bhattacharyya, Pathikrit; Zapata, Felipe; Haddock, Steven H D; Dunn, Casey W

    2015-01-01

    Siphonophores (Hydrozoa) have unparalleled colony-level complexity, precision of colony organization, and functional specialization between zooids (i.e., the units that make up colonies). Previous work has shown that, unlike other colonial animals, most growth in siphonophores is restricted to one or two well-defined growth zones that are the sites of both elongation and zooid budding. It remained unknown, however, how this unique colony growth and development is realized at the cellular level. To understand the colony-level growth and development of siphonophores at the cellular level, we characterize the distribution of proliferating cells and interstitial stem cells (i-cells) in the siphonophore Nanomia bijuga. Within the colony, we find evidence that i-cells are present at the tip of the horn, the structure within the growth zone that gives rise to new zooids. Co-localized gene expression of vasa-1, pl10, piwi, nanos-1, and nanos-2 suggests that i-cells persist in the youngest zooid buds and that i-cells become progressively restricted to specific regions within the zooids until they are mostly absent from the oldest zooids. The examined genes remain expressed in gametogenic regions. No evidence for i-cells is found in the stem between maturing zooids. Domains of high cell proliferation include regions where the examined genes are expressed, but also include some areas in which the examined genes were not expressed such as the stem within the growth zones. Cell proliferation in regions devoid of vasa-1, pl10, piwi, nanos-1, and nanos-2 expression indicates the presence of mitotically active epithelial cell lineages and, potentially, progenitor cell populations. We provide the first evidence for i-cells in a siphonophore. Our findings suggest maintenance of i-cell populations at the sites of growth zones and that these sites are the main source of i-cells. This restriction of stem cells to particular regions in the colony, in combination with localized budding

  7. De-repression of the RAC activator ELMO1 in cancer stem cells drives progression of TGFβ-deficient squamous cell carcinoma from transition zones

    PubMed Central

    McCauley, Heather A; Chevrier, Véronique; Birnbaum, Daniel; Guasch, Géraldine

    2017-01-01

    Squamous cell carcinomas occurring at transition zones are highly malignant tumors with poor prognosis. The identity of the cell population and the signaling pathways involved in the progression of transition zone squamous cell carcinoma are poorly understood, hence representing limited options for targeted therapies. Here, we identify a highly tumorigenic cancer stem cell population in a mouse model of transitional epithelial carcinoma and uncover a novel mechanism by which loss of TGFβ receptor II (Tgfbr2) mediates invasion and metastasis through de-repression of ELMO1, a RAC-activating guanine exchange factor, specifically in cancer stem cells of transition zone tumors. We identify ELMO1 as a novel target of TGFβ signaling and show that restoration of Tgfbr2 results in a complete block of ELMO1 in vivo. Knocking down Elmo1 impairs metastasis of carcinoma cells to the lung, thereby providing insights into the mechanisms of progression of Tgfbr2-deficient invasive transition zone squamous cell carcinoma. DOI: http://dx.doi.org/10.7554/eLife.22914.001 PMID:28219480

  8. Overexpression of Polygalacturonase in Transgenic Apple Trees Leads to a Range of Novel Phenotypes Involving Changes in Cell Adhesion1

    PubMed Central

    Atkinson, Ross G.; Schröder, Roswitha; Hallett, Ian C.; Cohen, Daniel; MacRae, Elspeth A.

    2002-01-01

    Polygalacturonases (PGs) cleave runs of unesterified GalUA that form homogalacturonan regions along the backbone of pectin. Homogalacturonan-rich pectin is commonly found in the middle lamella region of the wall where two adjacent cells abut and its integrity is important for cell adhesion. Transgenic apple (Malus domestica Borkh. cv Royal Gala) trees were produced that contained additional copies of a fruit-specific apple PG gene under a constitutive promoter. In contrast to previous studies in transgenic tobacco (Nicotiana tabacum) where PG overexpression had no effect on the plant (K.W. Osteryoung, K. Toenjes, B. Hall, V. Winkler, A.B. Bennett [1990] Plant Cell 2: 1239–1248), PG overexpression in transgenic apple led to a range of novel phenotypes. These phenotypes included silvery colored leaves and premature leaf shedding due to reduced cell adhesion in leaf abscission zones. Mature leaves had malformed and malfunctioning stomata that perturbed water relations and contributed to a brittle leaf phenotype. Chemical and ultrastructural analyses were used to relate the phenotypic changes to pectin changes in the leaf cell walls. The modification of apple trees by a single PG gene has offered a new and unexpected perspective on the role of pectin and cell wall adhesion in leaf morphology and stomatal development. PMID:12011344

  9. Protein expression differs between neural progenitor cells from the adult rat brain subventricular zone and olfactory bulb.

    PubMed

    Maurer, Martin H; Feldmann, Robert E; Bürgers, Heinrich F; Kuschinsky, Wolfgang

    2008-01-16

    Neural progenitor cells can be isolated from various regions of the adult mammalian brain, including the forebrain structures of the subventricular zone and the olfactory bulb. Currently it is unknown whether functional differences in these progenitor cell populations can already be found on the molecular level. Therefore, we compared protein expression profiles between progenitor cells isolated from the subventricular zone and the olfactory bulb using a proteomic approach based on two-dimensional gel electrophoresis and mass spectrometry. The subventricular zone and the olfactory bulb are connected by the Rostral Migratory Stream (RMS), in which glial fibrillary acidic protein (GFAP)-positive cells guide neuroblasts. Recent literature suggested that these GFAP-positive cells possess neurogenic potential themselves. In the current study, we therefore compared the cultured neurospheres for the fraction of GFAP-positive cells and their morphology of over a prolonged period of time. We found significant differences in the protein expression patterns between subventricular zone and olfactory bulb neural progenitor cells. Of the differentially expressed protein spots, 105 were exclusively expressed in the subventricular zone, 23 showed a lower expression and 51 a higher expression in the olfactory bulb. The proteomic data showed that more proteins are differentially expressed in olfactory bulb progenitors with regard to proteins involved in differentiation and microenvironmental integration, as compared to the subventricular zone progenitors. Compared to 94% of all progenitors of the subventricular zone expressed GFAP, nearly none in the olfactory bulb cultures expressed GFAP. Both GFAP-positive subpopulations differed also in morphology, with the olfactory bulb cells showing more branching. No differences in growth characteristics such as doubling time, and passage lengths could be found over 26 consecutive passages in the two cultures. In this study, we describe

  10. Solid oxide fuel cell systems with hot zones having improved reactant distribution

    DOEpatents

    Poshusta, Joseph C.; Booten, Charles W.; Martin, Jerry L.

    2012-11-06

    A Solid Oxide Fuel Cell (SOFC) system having a hot zone with a center cathode air feed tube for improved reactant distribution, a CPOX reactor attached at the anode feed end of the hot zone with a tail gas combustor at the opposing end for more uniform heat distribution, and a counter-flow heat exchanger for efficient heat retention.

  11. Solid oxide fuel cell systems with hot zones having improved reactant distribution

    DOEpatents

    Poshusta, Joseph C; Booten, Charles W; Martin, Jerry L

    2013-12-24

    A Solid Oxide Fuel Cell (SOFC) system having a hot zone with a center cathode air feed tube for improved reactant distribution, a CPOX reactor attached at the anode feed end of the hot zone with a tail gas combustor at the opposing end for more uniform heat distribution, and a counter-flow heat exchanger for efficient heat retention.

  12. Solid oxide fuel cell systems with hot zones having improved reactant distribution

    DOEpatents

    Poshusta, Joseph C.; Booten, Charles W.; Martin, Jerry L.

    2016-05-17

    A Solid Oxide Fuel Cell (SOFC) system having a hot zone with a center cathode air feed tube for improved reactant distribution, a CPOX reactor attached at the anode feed end of the hot zone with a tail gas combustor at the opposing end for more uniform heat distribution, and a counter-flow heat exchanger for efficient heat retention.

  13. Comparative Effect of Physicomechanical and Biomolecular Cues on Zone-Specific Chondrogenic Differentiation of Mesenchymal Stem Cells

    PubMed Central

    Moeinzadeh, Seyedsina; Shariati, Seyed Ramin Pajoum; Jabbari, Esmaiel

    2016-01-01

    Current tissue engineering approaches to regeneration of articular cartilage rarely restore the tissue to its normal state because the generated tissue lacks the intricate zonal organization of the native cartilage. Zonal regeneration of articular cartilage is hampered by the lack of knowledge for the relation between physical, mechanical, and biomolecular cues and zone-specific chondrogenic differentiation of progenitor cells. This work investigated in 3D the effect of TGF-β1, zone-specific growth factors, optimum matrix stiffness, and adding nanofibers on the expression of chondrogenic markers specific to the superficial, middle, and calcified zones of articular cartilage by the differentiating human mesenchymal stem cells (hMSCs). Growth factors included BMP-7, IGF-1, and hydroxyapatite (HA) for the superficial, middle, and calcified zones, respectively; optimum matrix stiffness was 80 kPa, 2.1 MPa, and 320 MPa; and nanofibers were aligned horizontal, random, and perpendicular to the gel surface. hMSCs with zone-specific cell densities were encapsulated in engineered hydrogels and cultured with or without TGF-β1, zone-specific growth factor, optimum matrix modulus, and fiber addition and cultured in basic chondrogenic medium. The expression of encapsulated cells was measured by mRNA, protein, and biochemical analysis. Results indicated that zone-specific matrix stiffness had a dominating effect on chondrogenic differentiation of hMSCs to the superficial and calcified zone phenotypes. Addition of aligned nanofibers parallel to the direction of gel surface significantly enhanced expression of Col II in the superficial zone chondrogenic differentiation of hMSCs. Conversely, biomolecular factor IGF-1 in combination with TGF-β1 had a dominating effect on the middle zone chondrogenic differentiation of hMSCs. Results of this work could potentially lead to the development of multilayer grafts mimicking the zonal organization of articular cartilage. PMID:27038568

  14. Differentiation potentials of perivascular cells in the bone tissue remodeling zones under microgravity

    NASA Astrophysics Data System (ADS)

    Rodionova, Natalia; Katkova, Olena

    Adaptive remodeling processes in the skeleton bones occur in the close topographical interconnection with blood capillaries followed by perivascular cells. Radioautographic studies with 3H- thymidine (Kimmel D.B., Fee W.S., 1980; Rodionova N.V., 1989, 2006) has shown that in osteogenesis zones there is sequential differentiation process of the perivascular cells into osteogenic ones. Using electron microscopy and cytochemistry we studied perivsacular cells in metaphysis of the rats femoral bones under conditions of modeling microgravity (28 days duration) and in femoral bones metaphyses of rats flown on board of the space laboratory (Spacelab - 2) It was revealed that population of the perivascular cells is not homogeneous in adaptive zones of the remodeling in both control and test groups (lowering support loading). This population comprises adjacent to endothelium little differentiated forms and isolated cells with differentiation features (specific volume of rough endoplasmic reticulum in cytoplasm is increased). Majority of the perivascular cells in the control group reveals reaction to alkaline phosphatase (marker of the osteogenic differentiation). In little differentiated cells this reaction is registered in nucleolus, nucleous and cytoplasm. In differentiating cells activity of the alkaline phosphatase is also detected on the outer surface of the cellular membrane. Unlike the control group in the bones of animals under microgravitaty reaction to the alkaline phosphatase is registered not for all cells of perivascular population. Part of the differentiating perivascular cells does not contain a product of the reaction. There is also visible trend of individual alkaline phosphatase containing perivascular cells amounts decrease (i.e. osteogenic cells-precursors). Under microgravity some little differentiated perivascular cells reveal destruction signs. Found decrease trend of the alkaline phosphatase containing cells (i.e. osteogenic cells) number in

  15. Involvements of PCD and changes in gene expression profile during self-pruning of spring shoots in sweet orange (Citrus sinensis).

    PubMed

    Zhang, Jin-Zhi; Zhao, Kun; Ai, Xiao-Yan; Hu, Chun-Gen

    2014-10-13

    Citrus shoot tips abscise at an anatomically distinct abscission zone (AZ) that separates the top part of the shoots into basal and apical portions (citrus self-pruning). Cell separation occurs only at the AZ, which suggests its cells have distinctive molecular regulation. Although several studies have looked into the morphological aspects of self-pruning process, the underlying molecular mechanisms remain unknown. In this study, the hallmarks of programmed cell death (PCD) were identified by TUNEL experiments, transmission electron microscopy (TEM) and histochemical staining for reactive oxygen species (ROS) during self-pruning of the spring shoots in sweet orange. Our results indicated that PCD occurred systematically and progressively and may play an important role in the control of self-pruning of citrus. Microarray analysis was used to examine transcriptome changes at three stages of self-pruning, and 1,378 differentially expressed genes were identified. Some genes were related to PCD, while others were associated with cell wall biosynthesis or metabolism. These results strongly suggest that abscission layers activate both catabolic and anabolic wall modification pathways during the self-pruning process. In addition, a strong correlation was observed between self-pruning and the expression of hormone-related genes. Self-pruning plays an important role in citrus floral bud initiation. Therefore, several key flowering homologs of Arabidopsis and tomato shoot apical meristem (SAM) activity genes were investigated in sweet orange by real-time PCR and in situ hybridization, and the results indicated that these genes were preferentially expressed in SAM as well as axillary meristem. Based on these findings, a model for sweet orange spring shoot self-pruning is proposed, which will enable us to better understand the mechanism of self-pruning and abscission.

  16. Homeobox NKX2-3 promotes marginal-zone lymphomagenesis by activating B-cell receptor signalling and shaping lymphocyte dynamics

    PubMed Central

    Robles, Eloy F.; Mena-Varas, Maria; Barrio, Laura; Merino-Cortes, Sara V.; Balogh, Péter; Du, Ming-Qing; Akasaka, Takashi; Parker, Anton; Roa, Sergio; Panizo, Carlos; Martin-Guerrero, Idoia; Siebert, Reiner; Segura, Victor; Agirre, Xabier; Macri-Pellizeri, Laura; Aldaz, Beatriz; Vilas-Zornoza, Amaia; Zhang, Shaowei; Moody, Sarah; Calasanz, Maria Jose; Tousseyn, Thomas; Broccardo, Cyril; Brousset, Pierre; Campos-Sanchez, Elena; Cobaleda, Cesar; Sanchez-Garcia, Isidro; Fernandez-Luna, Jose Luis; Garcia-Muñoz, Ricardo; Pena, Esther; Bellosillo, Beatriz; Salar, Antonio; Baptista, Maria Joao; Hernandez-Rivas, Jesús Maria; Gonzalez, Marcos; Terol, Maria Jose; Climent, Joan; Ferrandez, Antonio; Sagaert, Xavier; Melnick, Ari M.; Prosper, Felipe; Oscier, David G.; Carrasco, Yolanda R.; Dyer, Martin J. S.; Martinez-Climent, Jose A.

    2016-01-01

    NKX2 homeobox family proteins have a role in cancer development. Here we show that NKX2-3 is overexpressed in tumour cells from a subset of patients with marginal-zone lymphomas, but not with other B-cell malignancies. While Nkx2-3-deficient mice exhibit the absence of marginal-zone B cells, transgenic mice with expression of NKX2-3 in B cells show marginal-zone expansion that leads to the development of tumours, faithfully recapitulating the principal clinical and biological features of human marginal-zone lymphomas. NKX2-3 induces B-cell receptor signalling by phosphorylating Lyn/Syk kinases, which in turn activate multiple integrins (LFA-1, VLA-4), adhesion molecules (ICAM-1, MadCAM-1) and the chemokine receptor CXCR4. These molecules enhance migration, polarization and homing of B cells to splenic and extranodal tissues, eventually driving malignant transformation through triggering NF-κB and PI3K-AKT pathways. This study implicates oncogenic NKX2-3 in lymphomagenesis, and provides a valid experimental mouse model for studying the biology and therapy of human marginal-zone B-cell lymphomas. PMID:27297662

  17. Immunohistochemical analysis of the novel marginal zone B-cell marker IRTA1 in malignant lymphoma.

    PubMed

    Ikeda, Jun-Ichiro; Kohara, Masaharu; Tsuruta, Yoko; Nojima, Satoshi; Tahara, Shinichiro; Ohshima, Kenji; Kurashige, Masako; Wada, Naoki; Morii, Eiichi

    2017-01-01

    Marginal zone lymphoma (MZL) is a low-grade B-cell lymphoma derived from marginal zone B cells. Because of a lack of specific immunohistochemical markers, MZL is mainly diagnosed based on the cytological appearance and growth pattern of the tumor. Marginal zone B cells were recently shown to selectively express immunoglobulin superfamily receptor translocation-associated 1 (IRTA1), but the antibody used in that study is not commercially available. We therefore investigated the IRTA1 expression in nonneoplastic lymphoid tissues and 261 malignant lymphomas, examining the ability of a commercially available antibody to accurately diagnose MZL. Among 37 MZLs, 23 of 25 extranodal MZLs of mucosa-associated lymphoid tissue (MALT lymphomas), 3 of 6 splenic MZLs and 3 of 6 nodal MZLs were positive for IRTA1. Among the 98 diffuse large B-cell lymphomas, 33 were positive for IRTA1, including 1 of 38 follicular lymphomas, and all precursor B-lymphoblastic (2/2) and T-lymphoblastic (7/7) leukemia/lymphomas. Other mature B-cell and T-cell lymphomas, and Hodgkin lymphoma were negative for IRTA1. In MALT lymphoma, positive cells were detected mainly in intraepithelial and subepithelial marginal zone B cells. In 1 case of grade 3 follicular lymphoma, IRTA1 was also expressed in the area of large cell transformation. When tumors were classified as germinal center B cell-like (GCB) or non-GCB using the algorithm of Hans, positive expression of IRTA1 was correlated significantly with non-GCB diffuse large B-cell lymphomas (P < .05). These results demonstrated the ability of the commercially available IRTA1 antibody to distinguish MALT lymphoma from other low-grade B-cell lymphomas. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Stem cell-based tissue-engineering for treatment of meniscal tears in the avascular zone.

    PubMed

    Zellner, Johannes; Hierl, Katja; Mueller, Michael; Pfeifer, Christian; Berner, Arne; Dienstknecht, Thomas; Krutsch, Werner; Geis, Sebastian; Gehmert, Sebastian; Kujat, Richard; Dendorfer, Sebastian; Prantl, Lukas; Nerlich, Michael; Angele, Peter

    2013-10-01

    Meniscal tears in the avascular zone have a poor self-healing potential, however partial meniscectomy predisposes the knee for early osteoarthritis. Tissue engineering with mesenchymal stem cells and a hyaluronan collagen based scaffold is a promising approach to repair meniscal tears in the avascular zone. 4 mm longitudinal meniscal tears in the avascular zone of lateral menisci of New Zealand White Rabbits were performed. The defect was left empty, sutured with a 5-0 suture or filled with a hyaluronan/collagen composite matrix without cells, with platelet rich plasma or with autologous mesenchymal stem cells. Matrices with stem cells were in part precultured in chondrogenic medium for 14 days prior to the implantation. Menisci were harvested at 6 and 12 weeks. The developed repair tissue was analyzed macroscopically, histologically and biomechanically. Untreated defects, defects treated with suture alone, with cell-free or with platelet rich plasma seeded implants showed a muted fibrous healing response. The implantation of stem cell-matrix constructs initiated fibrocartilage-like repair tissue, with better integration and biomechanical properties in the precultured stem cell-matrix group. A hyaluronan-collagen based composite scaffold seeded with mesenchymal stem cells is more effective in the repair avascular meniscal tear with stable meniscus-like tissue and to restore the native meniscus. Copyright © 2013 Wiley Periodicals, Inc., a Wiley Company.

  19. Lyme disease and relapsing fever Borrelia elongate through zones of peptidoglycan synthesis that mark division sites of daughter cells.

    PubMed

    Jutras, Brandon Lyon; Scott, Molly; Parry, Bradley; Biboy, Jacob; Gray, Joe; Vollmer, Waldemar; Jacobs-Wagner, Christine

    2016-08-16

    Agents that cause Lyme disease, relapsing fever, leptospirosis, and syphilis belong to the phylum Spirochaetae-a unique lineage of bacteria most known for their long, spiral morphology. Despite the relevance to human health, little is known about the most fundamental aspects of spirochete growth. Here, using quantitative microscopy to track peptidoglycan cell-wall synthesis, we found that the Lyme disease spirochete Borrelia burgdorferi displays a complex pattern of growth. B. burgdorferi elongates from discrete zones that are both spatially and temporally regulated. In addition, some peptidoglycan incorporation occurs along the cell body, with the notable exception of a large region at the poles. Newborn cells inherit a highly active zone of peptidoglycan synthesis at midcell that contributes to elongation for most of the cell cycle. Concomitant with the initiation of nucleoid separation and cell constriction, second and third zones of elongation are established at the 1/4 and 3/4 cellular positions, marking future sites of division for the subsequent generation. Positioning of elongation zones along the cell is robust to cell length variations and is relatively precise over long distances (>30 µm), suggesting that cells ‟sense" relative, as opposed to absolute, cell length to establish zones of peptidoglycan synthesis. The transition from one to three zones of peptidoglycan growth during the cell cycle is also observed in relapsing fever Borrelia. However, this mode of growth does not extend to representative species from other spirochetal genera, suggesting that this distinctive growth mode represents an evolutionary divide in the spirochete phylum.

  20. Analysis of Phosphorylation of the Receptor-Like Protein Kinase HAESA during Arabidopsis Floral Abscission

    PubMed Central

    Taylor, Isaiah; Wang, Ying; Seitz, Kati; Baer, John; Bennewitz, Stefan; Mooney, Brian P.; Walker, John C.

    2016-01-01

    Receptor-like protein kinases (RLKs) are the largest family of plant transmembrane signaling proteins. Here we present functional analysis of HAESA, an RLK that regulates floral organ abscission in Arabidopsis. Through in vitro and in vivo analysis of HAE phosphorylation, we provide evidence that a conserved phosphorylation site on a region of the HAE protein kinase domain known as the activation segment positively regulates HAE activity. Additional analysis has identified another putative activation segment phosphorylation site common to multiple RLKs that potentially modulates HAE activity. Comparative analysis suggests that phosphorylation of this second activation segment residue is an RLK specific adaptation that may regulate protein kinase activity and substrate specificity. A growing number of RLKs have been shown to exhibit biologically relevant dual specificity toward serine/threonine and tyrosine residues, but the mechanisms underlying dual specificity of RLKs are not well understood. We show that a phospho-mimetic mutant of both HAE activation segment residues exhibits enhanced tyrosine auto-phosphorylation in vitro, indicating phosphorylation of this residue may contribute to dual specificity of HAE. These results add to an emerging framework for understanding the mechanisms and evolution of regulation of RLK activity and substrate specificity. PMID:26784444

  1. Oxidation of F-actin controls the terminal steps of cytokinesis

    PubMed Central

    Frémont, Stéphane; Hammich, Hussein; Bai, Jian; Wioland, Hugo; Klinkert, Kerstin; Rocancourt, Murielle; Kikuti, Carlos; Stroebel, David; Romet-Lemonne, Guillaume; Pylypenko, Olena; Houdusse, Anne; Echard, Arnaud

    2017-01-01

    Cytokinetic abscission, the terminal step of cell division, crucially depends on the local constriction of ESCRT-III helices after cytoskeleton disassembly. While the microtubules of the intercellular bridge are cut by the ESCRT-associated enzyme Spastin, the mechanism that clears F-actin at the abscission site is unknown. Here we show that oxidation-mediated depolymerization of actin by the redox enzyme MICAL1 is key for ESCRT-III recruitment and successful abscission. MICAL1 is recruited to the abscission site by the Rab35 GTPase through a direct interaction with a flat three-helix domain found in MICAL1 C terminus. Mechanistically, in vitro assays on single actin filaments demonstrate that MICAL1 is activated by Rab35. Moreover, in our experimental conditions, MICAL1 does not act as a severing enzyme, as initially thought, but instead induces F-actin depolymerization from both ends. Our work reveals an unexpected role for oxidoreduction in triggering local actin depolymerization to control a fundamental step of cell division. PMID:28230050

  2. 75 FR 64248 - Approval for Manufacturing Authority Foreign-Trade Zone 196 ATC Logistics & Electronics (Cell...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-19

    ... Authority Foreign-Trade Zone 196 ATC Logistics & Electronics (Cell Phone Kitting) Fort Worth, TX Pursuant to... Foreign-Trade Zones Board (the Board) adopts the following Order: Whereas, ATC Logistics & Electronics... Logistics & Electronics, as described in the application and Federal Register notice, is approved, subject...

  3. Specialized zones of development in roots

    NASA Technical Reports Server (NTRS)

    Ishikawa, H.; Evans, M. L.

    1995-01-01

    The authors propose using the term "distal elongation zone" (DEZ) rather than "postmitotic isodiametric growth zone" to refer to the group of cells between the apical meristem and the elongation zone in plant roots. Reasons presented for the change are that the proposed DEZ includes many cells that are still dividing, most cells in the region are not isodiametric, and the pattern of cell expansion in this region varies with position in the region. Cells in the DEZ respond to gravistimulation, mechanical impedance, electrotropic stimulation, water stress, and auxin. Differences in gene expression patterns between DEZ cells and cells in the main elongation zone are noted.

  4. Protective Effects of Fetal Zone Steroids Are Comparable to Estradiol in Hyperoxia-Induced Cell Death of Immature Glia.

    PubMed

    Hübner, Stephanie; Sunny, Donna E; Pöhlke, Christine; Ruhnau, Johanna; Vogelgesang, Antje; Reich, Bettina; Heckmann, Matthias

    2017-05-01

    Impaired neurodevelopment in preterm infants is caused by prematurity itself; however, hypoxia/ischemia, inflammation, and hyperoxia contribute to the extent of impairment. Because preterm birth is accompanied by a dramatic decrease in 17β-estradiol (E2) and progesterone, preliminary clinical studies have been carried out to substitute these steroids in preterm infants; however, they failed to confirm significantly improved neurologic outcomes. We therefore hypothesized that the persistently high postnatal production of fetal zone steroids [mainly dehydroepiandrosterone (DHEA)] until term could interfere with E2-mediated protection. We investigated whether E2 could reduce hyperoxia-mediated apoptosis in three immature glial cell types and detected the involved receptors. Thereafter, we investigated protection by the fetal zone steroids DHEA, 16α-hydroxy-DHEA, and androstenediol. For DHEA, the involved receptors were evaluated. We examined aromatases, which convert fetal zone steroids into more estrogenic compounds. Finally, cotreatment was compared against single hormone treatment to investigate synergism. In all cell types, E2 and fetal zone steroids resulted in significant dose-dependent protection, whereas the mediating receptors differed. The neuroprotection by fetal zone steroids highly depended on the cell type-specific expression of aromatases, the receptor repertoire, and the potency of the fetal zone steroids toward these receptors. No synergism in fetal zone steroid and E2 cotreatment was detected in two of three cell types. Therefore, E2 supplementation may not be beneficial with respect to neuroprotection because fetal zone steroids circulate in persistently high concentrations until term in preterm infants. Hence, a refined experimental model for preterm infants is required to investigate potential treatments. Copyright © 2017 Endocrine Society.

  5. Eradication of Borrelia burgdorferi infection in primary marginal zone B-cell lymphoma of the skin.

    PubMed

    Roggero, E; Zucca, E; Mainetti, C; Bertoni, F; Valsangiacomo, C; Pedrinis, E; Borisch, B; Piffaretti, J C; Cavalli, F; Isaacson, P G

    2000-02-01

    Primary cutaneous B-cell lymphomas have been associated with Borrelia burgdorferi, the spirochete responsible for Lyme disease. Recently, cutaneous marginal zone B-cell lymphoma has been proposed as a distinct clinical-pathological entity. We report a case of primary cutaneous marginal zone lymphoma, associated with B burgdorferi infection. Polymerase chain reaction (PCR) amplification of the third complementarity determining region (CDR3) of the immunoglobulin heavy chain gene showed the presence of a monoclonal lymphoproliferation, therefore strengthening the histological diagnosis of a malignant process. B burgdorfer-specific hbb gene sequences were detected by PCR in the lymphoma tissue at diagnosis but not after antibiotic treatment. A nearly complete clinical and histological regression was observed after B burgdorferi eradication, with immunohistochemistry studies showing disappearance of plasma cell differentiation and a marked decline in the number of CD3+ T cells and Ki-67+ cells. Our case confirms the link between B burgdorferi and some cutaneous lymphomas. The disappearance of the microorganism accompanied by the unequivocal decrease of most indicators of active T- and B-cell immune response strongly supported a pathogenetic role for B burgdorferi in sustaining an antigen-driven development and growth of this cutaneous marginal zone lymphoma. Antibiotic therapy (analogous to Helicobacter pylori infection in gastric MALT lymphoma) might be helpful with the aim of averting or at least deferring the indication for more aggressive treatment.

  6. Synchrony of clonal cell proliferation and contiguity of clonally related cells: production of mosaicism in the ventricular zone of developing mouse neocortex

    NASA Technical Reports Server (NTRS)

    Cai, L.; Hayes, N. L.; Nowakowski, R. S.

    1997-01-01

    We have analyzed clonal cell proliferation in the ventricular zone (VZ) of the early developing mouse neocortex with a replication-incompetent retrovirus encoding human placental alkaline phosphatase (AP). The retrovirus was injected into the lateral ventricles on embryonic day 11 (E11), i.e., at the onset of neuronogenesis. Three days postinjection, on E14, a total of 259 AP-labeled clones of various sizes were found in 7 fetal brains. There are approximately 7 cell cycles between E11 and E14 (), and there is a 1-2 cell cycle delay between retroviral injection and the production of a retrovirally labeled "founder" cell; thus, we estimate that the "age" of the clones was about 5-6 cell cycles. Almost one-half of the clones (48.3%) identified were pure proliferating clones containing cells only in the VZ. Another 18.5% contained both proliferating and postproliferative cells, and 33.2% contained only postproliferative cells. It was striking that over 90% of the clonally related proliferating cells occurred in clusters of two or more apparently contiguous cells, and about 73% of the proliferating cells occurred in clusters of three or more cells. Regardless of the number of cells in the clone, these clusters were tightly packed and confined to a single level of the VZ. This clustering of proliferating cells indicates that clonally related cells maintain neighbor-neighbor relationships as they undergo interkinetic nuclear migration and progress through several cell cycles, and, as a result, the ventricular zone is a mosaic of small clusters of clonally related and synchronously cycling cells. In addition, cells in the intermediate zone and the cortical plate were also frequently clustered, indicating that they became postproliferative at a similar time and that the output of the VZ is influenced by its mosaic structure.

  7. Engineering of hyaline cartilage with a calcified zone using bone marrow stromal cells.

    PubMed

    Lee, W D; Hurtig, M B; Pilliar, R M; Stanford, W L; Kandel, R A

    2015-08-01

    In healthy joints, a zone of calcified cartilage (ZCC) provides the mechanical integration between articular cartilage and subchondral bone. Recapitulation of this architectural feature should serve to resist the constant shear force from the movement of the joint and prevent the delamination of tissue-engineered cartilage. Previous approaches to create the ZCC at the cartilage-substrate interface have relied on strategic use of exogenous scaffolds and adhesives, which are susceptible to failure by degradation and wear. In contrast, we report a successful scaffold-free engineering of ZCC to integrate tissue-engineered cartilage and a porous biodegradable bone substitute, using sheep bone marrow stromal cells (BMSCs) as the cell source for both cartilaginous zones. BMSCs were predifferentiated to chondrocytes, harvested and then grown on a porous calcium polyphosphate substrate in the presence of triiodothyronine (T3). T3 was withdrawn, and additional predifferentiated chondrocytes were placed on top of the construct and grown for 21 days. This protocol yielded two distinct zones: hyaline cartilage that accumulated proteoglycans and collagen type II, and calcified cartilage adjacent to the substrate that additionally accumulated mineral and collagen type X. Constructs with the calcified interface had comparable compressive strength to native sheep osteochondral tissue and higher interfacial shear strength compared to control without a calcified zone. This protocol improves on the existing scaffold-free approaches to cartilage tissue engineering by incorporating a calcified zone. Since this protocol employs no xenogeneic material, it will be appropriate for use in preclinical large-animal studies. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  8. Changes in the population of perivascular cells in the bone tissue remodeling zones under microgravity

    NASA Astrophysics Data System (ADS)

    Katkova, Olena; Rodionova, Natalia; Shevel, Ivan

    2016-07-01

    Microgravity and long-term hypokinesia induce reduction both in bone mass and mineral saturation, which can lead to the development of osteoporosis and osteopenia. (Oganov, 2003). Reorganizations and adaptive remodeling processes in the skeleton bones occur in the topographical interconnection with blood capillaries and perivascular cells. Radioautographic studies with 3H- thymidine (Kimmel, Fee, 1980; Rodionova, 1989, 2006) have shown that in osteogenesis zones there is sequential differentiation process of the perivascular cells into osteogenic. Hence the study of populations of perivascular stromal cells in areas of destructive changes is actual. Perivascular cells from metaphysis of the rat femoral bones under conditions of modeling microgravity were studied using electron microscopy and cytochemistry (hindlimb unloading, 28 days duration) and biosatellite «Bion-M1» (duration of flight from April 19 till May 19, 2013 on C57, black mice). It was revealed that both control and test groups populations of the perivascular cells are not homogeneous in remodeling adaptive zones. These populations comprise of adjacent to endothelium poorly differentiated forms and isolated cells with signs of differentiation (specific increased volume of rough endoplasmic reticulum in cytoplasm). Majority of the perivascular cells in the control group (modeling microgravity) reveals reaction to alkaline phosphatase (marker of the osteogenic differentiation). In poorly differentiated cells this reaction is registered in nucleolus, nucleous and cytoplasm. In differentiating cells activity of the alkaline phosphatase is also detected on the outer surface of the cellular membrane. Unlike the control group in the bones of experimental animals reaction to the alkaline phosphatase is registered not in all cells of perivascular population. Part of the differentiating perivascular cells does not contain a product of the reaction. Under microgravity some poorly differentiated perivascular

  9. Optimizing Culture Medium Composition to Improve Oligodendrocyte Progenitor Cell Yields In Vitro from Subventricular Zone-Derived Neural Progenitor Cell Neurospheres

    PubMed Central

    Franco, Paula G.; Pasquini, Juana M.; Silvestroff, Lucas

    2015-01-01

    Neural Stem and Progenitor Cells (NSC/NPC) are gathering tangible recognition for their uses in cell therapy and cell replacement therapies for human disease, as well as a model system to continue research on overall neural developmental processes in vitro. The Subventricular Zone is one of the largest NSC/NPC niches in the developing mammalian Central Nervous System, and persists through to adulthood. Oligodendrocyte progenitor cell (OPC) enriched cultures are usefull tools for in vitro studies as well as for cell replacement therapies for treating demyelination diseases. We used Subventricular Zone-derived NSC/NPC primary cultures from newborn mice and compared the effects of different growth factor combinations on cell proliferation and OPC yield. The Platelet Derived Growth Factor-AA and BB homodimers had a positive and significant impact on OPC generation. Furthermore, heparin addition to the culture media contributed to further increase overall culture yields. The OPC generated by this protocol were able to mature into Myelin Basic Protein-expressing cells and to interact with neurons in an in vitro co-culture system. As a whole, we describe an optimized in vitro method for increasing OPC. PMID:25837625

  10. Fruitlet abscission: A cDNA-AFLP approach to study genes differentially expressed during shedding of immature fruits reveals the involvement of a putative auxin hydrogen symporter in apple (Malus domestica L. Borkh).

    PubMed

    Dal Cin, Valeriano; Barbaro, Enrico; Danesin, Marcello; Murayama, Hideki; Velasco, Riccardo; Ramina, Angelo

    2009-08-01

    Apple Malus X domestica fruitlet abscission is preceded by a stimulation of ethylene biosynthesis and a gain in sensitivity to the hormone. This phase was studied by a differential screening carried out by cDNA-AFLP in abscising (AF) and non-abscising (NAF) fruitlet populations. Fifty-three primer combinations allowed for the isolation of 131, 66 and 30 differentially expressed bands from cortex, peduncle and seed, respectively. All sequences were then classified as up- or down-regulated by comparing the profile in AFs and NAFs. Almost all of these sequences showed significant homology to genes encoding proteins with known or putative function. The gene ontology analysis of the TDFs isolated indicated a deep change in metabolism, plastid and hormonal status, especially auxin. Furthermore, some common elements between abscission and senescence were identified. The isolation of the full length of one of these TDFs allowed for the identification of a gene encoding an auxin hydrogen symporter (MdAHS). Bioinformatic analysis indicated that the deduced protein shares some features with other auxin efflux carriers, which include PINs. Nevertheless the 3D structure pointed out substantial differences and a conformation largely dissimilar from canonical ion transporters. The expression analysis demonstrated that this gene is regulated by light and development but not affected by ethylene or auxin.

  11. Fractone-heparan sulphates mediate FGF-2 stimulation of cell proliferation in the adult subventricular zone.

    PubMed

    Douet, V; Kerever, A; Arikawa-Hirasawa, E; Mercier, F

    2013-04-01

    Fractones are extracellular matrix structures that form a niche for neural stem cells and their immediate progeny in the subventricular zone of the lateral ventricle (SVZa), the primary neurogenic zone in the adult brain. We have previously shown that heparan sulphates (HS) associated with fractones bind fibroblast growth factor-2 (FGF-2), a powerful mitotic growth factor in the SVZa. Here, our objective was to determine whether the binding of FGF-2 to fractone-HS is implicated in the mechanism leading to cell proliferation in the SVZa. Heparitinase-1 was intracerebroventricularly injected with FGF-2 to N-desulfate HS proteoglycans and determine whether the loss of HS and of FGF-2 binding to fractones modifies FGF-2 effect on cell proliferation. We also examined in vivo the binding of Alexa-Fluor-FGF-2 in relationship with the location of HS immunoreactivity in the SVZa. Heparatinase-1 drastically reduced the stimulatory effect of FGF-2 on cell proliferation in the SVZa. Alexa-Fluor-FGF-2 binding was strictly co-localized with HS immunoreactivity in fractones and adjacent vascular basement membranes in the SVZa. Our results demonstrate that FGF-2 requires HS to stimulate cell proliferation in the SVZa and suggest that HS associated with fractones and vascular basement membranes are responsible for activating FGF-2. Therefore, fractones and vascular basement membranes may function as a HS niche to drive cell proliferation in the adult neurogenic zone. © 2013 Blackwell Publishing Ltd.

  12. Disentangling the influence of cell phone usage in the dilemma zone: An econometric approach.

    PubMed

    Eluru, Naveen; Yasmin, Shamsunnahar

    2016-11-01

    This paper focuses on developing an analysis framework to study the impact of cell phone treatment (cell phone type and call status) on driver behavior in the presence of a dilemma zone. Specifically, we examine how the treatment influences the driver maneuver decision at the intersection (stop or cross) and the eventual success of the maneuver. For a stop maneuver, success is defined as stopping before the stop line. Similarly, for a cross maneuver, success is defined as clearing the intersection safely before the light turns red. The eventual success or failure of the driver's decision process is dependent on the factors that affected the maneuver decision. Hence it is important to recognize the interconnectedness of the stop or cross decision with its eventual success (or failure). Toward this end, we formulate and estimate a joint framework to analyze the stop/cross decision with its eventual success (or failure) simultaneously. The study is conducted based on driving simulator data provided online for the 2014 Transportation Research Board Data Contest at http://depts.washington.edu/hfsm/upload.php. The model is estimated to analyze drivers' behavior at the onset of yellow by employing exogenous variables from three broad categories: driver characteristics, cell phone attributes and driving attributes. We also generate probability surfaces to identify dilemma zone distribution associated with different cell phone treatment types. The plots clearly illustrate the impact of various cellphone treatments on driver dilemma zone behavior. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Transient removal of alkaline zones after excitation of Chara cells is associated with inactivation of high conductance in the plasmalemma

    PubMed Central

    2009-01-01

    The action potential (AP) of excitable plant cells is a multifunctional physiological signal. Its generation in characean algae suppresses the pH banding for 15–30 min and enhances the heterogeneity of spatial distribution of photosynthetic activity. This suppression is largely due to the cessation of H+ influx (OH− efflux) in the alkaline cell regions. Measurements of local pH and membrane conductance in individual space-clamped alkaline zones (small cell areas bathed in an isolated pool of external medium) showed that the AP generation is followed by the transient disappearance of alkaline zone in parallel with a large decrease in membrane conductance. These changes, specific to alkaline zones, were only observed under continuous illumination following a relaxation period of at least 15 min after previous excitation. The excitation of dark-adapted cells produced no conductance changes in the post-excitation period. The results indicate that the origin of alkaline zones in characean cells is not due to operation of electroneutral H+/HCO3− symport or OH−/HCO3− antiport. It is concluded that the membrane excitation is associated with inactivation of plasmalemma high conductance in the alkaline cell regions. PMID:19820298

  14. Neural stem cell heterogeneity through time and space in the ventricular-subventricular zone.

    PubMed

    Rushing, Gabrielle; Ihrie, Rebecca A

    2016-08-01

    The origin and classification of neural stem cells (NSCs) has been a subject of intense investigation for the past two decades. Efforts to categorize NSCs based on their location, function and expression have established that these cells are a heterogeneous pool in both the embryonic and adult brain. The discovery and additional characterization of adult NSCs has introduced the possibility of using these cells as a source for neuronal and glial replacement following injury or disease. To understand how one could manipulate NSC developmental programs for therapeutic use, additional work is needed to elucidate how NSCs are programmed and how signals during development are interpreted to determine cell fate. This review describes the identification, classification and characterization of NSCs within the large neurogenic niche of the ventricular-subventricular zone (V-SVZ). A literature search was conducted using Pubmed including the keywords "ventricular-subventricular zone," "neural stem cell," "heterogeneity," "identity" and/or "single cell" to find relevant manuscripts to include within the review. A special focus was placed on more recent findings using single-cell level analyses on neural stem cells within their niche(s). This review discusses over 20 research articles detailing findings on V-SVZ NSC heterogeneity, over 25 articles describing fate determinants of NSCs, and focuses on 8 recent publications using distinct single-cell analyses of neural stem cells including flow cytometry and RNA-seq. Additionally, over 60 manuscripts highlighting the markers expressed on cells within the NSC lineage are included in a chart divided by cell type. Investigation of NSC heterogeneity and fate decisions is ongoing. Thus far, much research has been conducted in mice however, findings in human and other mammalian species are also discussed here. Implications of NSC heterogeneity established in the embryo for the properties of NSCs in the adult brain are explored, including

  15. Human forniceal region is the stem cell-rich zone of the conjunctival epithelium.

    PubMed

    Harun, Mohd Hairul Nizam; Sepian, Siti Norzalehawati; Chua, Kien-Hui; Ropilah, Abd Rahman; Abd Ghafar, Norzana; Che-Hamzah, Jemaima; Bt Hj Idrus, Ruszymah; Annuar, Faridah Hanom

    2013-03-01

    The anterior surface of the eye is covered by several physically contiguous but histologically distinguishable epithelia overlying the cornea, limbus, bulbar conjunctiva, fornix conjunctiva, and palpebral conjunctiva. The self-renewing nature of the conjunctival epithelia makes their long-term survival ultimately dependent on small populations of stem cells. Hence, the objective of this study was to investigate the expression of the stem cell genes Sox2, OCT4, NANOG, Rex1, NES, and ABCG2 in cultured human conjunctival epithelium from different conjunctival zones, namely, the bulbar, palpebral and fornix zones. Three samples were taken from patients with primary pterygium and cataract (age range 56-66 years) who presented to our eye clinic at the UKM Medical Centre. The eye was examined with slit lamp to ensure there was no underlying ocular surface diseases and glaucoma. Conjunctival tissue was taken from patients who underwent a standard cataract or pterygium operation as a primary procedure. Tissues were digested, cultured, and propagated until an adequate number of cells was obtained. Total RNA was extracted and subjected to expression analysis of conjunctival epithelium genes (KRT4, KRT13, KRT19) and stem cell genes (Sox2, OCT4, NANOG, Rex1, NES, ABCG2) by reverse transcriptase-PCR and 2% agarose gel electrophoresis. The expression of Sox2, OCT4, and NANOG genes were detected in the fornical cells, while bulbar cells only expressed Sox2 and palpebral cells only expressed OCT4. Based on these results, the human forniceal region expresses a higher number of stem cell genes than the palpebral and bulbar conjunctiva.

  16. Fine-tuning of actin dynamics by the HSPB8-BAG3 chaperone complex facilitates cytokinesis and contributes to its impact on cell division.

    PubMed

    Varlet, Alice Anaïs; Fuchs, Margit; Luthold, Carole; Lambert, Herman; Landry, Jacques; Lavoie, Josée N

    2017-07-01

    The small heat shock protein HSPB8 and its co-chaperone BAG3 are proposed to regulate cytoskeletal proteostasis in response to mechanical signaling in muscle cells. Here, we show that in dividing cells, the HSPB8-BAG3 complex is instrumental to the accurate disassembly of the actin-based contractile ring during cytokinesis, a process required to allow abscission of daughter cells. Silencing of HSPB8 markedly decreased the mitotic levels of BAG3 in HeLa cells, supporting its crucial role in BAG3 mitotic functions. Cells depleted of HSPB8 were delayed in cytokinesis, remained connected via a disorganized intercellular bridge, and exhibited increased incidence of nuclear abnormalities that result from failed cytokinesis (i.e., bi- and multi-nucleation). Such phenotypes were associated with abnormal accumulation of F-actin at the intercellular bridge of daughter cells at telophase. Remarkably, the actin sequestering drug latrunculin A, like the inhibitor of branched actin polymerization CK666, normalized F-actin during cytokinesis and restored proper cell division in HSPB8-depleted cells, implicating deregulated actin dynamics as a cause of abscission failure. Moreover, this HSPB8-dependent phenotype could be corrected by rapamycin, an autophagy-promoting drug, whereas it was mimicked by drugs impairing lysosomal function. Together, the results further support a role for the HSPB8-BAG3 chaperone complex in quality control of actin-based structure dynamics that are put under high tension, notably during cell cytokinesis. They expand a so-far under-appreciated connection between selective autophagy and cellular morphodynamics that guide cell division.

  17. On the Origin of the Double-cell Meridional Circulation in the Solar Convection Zone

    NASA Astrophysics Data System (ADS)

    Pipin, V. V.; Kosovichev, A. G.

    2018-02-01

    Recent advances in helioseismology, numerical simulations and mean-field theory of solar differential rotation have shown that the meridional circulation pattern may consist of two or more cells in each hemisphere of the convection zone. According to the mean-field theory the double-cell circulation pattern can result from the sign inversion of a nondiffusive part of the radial angular momentum transport (the so-called Λ-effect) in the lower part of the solar convection zone. Here, we show that this phenomenon can result from the radial inhomogeneity of the Coriolis number, which depends on the convective turnover time. We demonstrate that if this effect is taken into account then the solar-like differential rotation and the double-cell meridional circulation are both reproduced by the mean-field model. The model is consistent with the distribution of turbulent velocity correlations determined from observations by tracing motions of sunspots and large-scale magnetic fields, indicating that these tracers are rooted just below the shear layer.

  18. Tumor formation of prostate cancer cells influenced by stromal cells from the transitional or peripheral zones of the normal prostate

    PubMed Central

    Zhao, Fu-Jun; Han, Bang-Min; Yu, Sheng-Qiang; Xia, Shu-Jie

    2009-01-01

    This study was designed to investigate the different involvements of prostatic stromal cells from the normal transitional zone (TZ) or peripheral zone (PZ) in the carcinogenesis of prostate cancer (PCa) epithelial cells (PC-3) in vitro and in vivo co-culture models. Ultra-structures and gene expression profiles of primary cultures of human prostatic stromal cells from the normal TZ or PZ were analyzed by electron microscopy and microarray analysis. In vitro and in vivo co-culture models composed of normal TZ or PZ stromal cells and human PCa PC-3 cells were established. We assessed tumor growth and weight in the in vivo nude mice model. There are morphological and ultra-structural differences in stromal cells from TZ and PZ of the normal prostate. In all, 514 differentially expressed genes were selected by microarray analysis; 483 genes were more highly expressed in stromal cells from TZ and 31 were more highly expressed in those from PZ. Co-culture with PZ stromal cells and transforming growth factor-β1 (TGF-β1) increased the tumor growth of PC-3 cells in vitro and in vivo, as well as Bcl-2 expression. On the other hand, stromal cells of TZ suppressed PC-3 cell tumor growth in the mouse model. We conclude that ultra-structures and gene expression differ between the stromal cells from TZ or PZ of the normal prostate, and stroma–epithelium interactions from TZ or PZ might be responsible for the distinct zonal localization of prostate tumor formation. PMID:19122679

  19. Seasonal Changes in Leaf Area of Amazon Forests from Leaf Flushing and Abscission

    NASA Astrophysics Data System (ADS)

    Samanta, A.; Knyazikhin, Y.; Xu, L.; Dickinson, R.; Fu, R.; Costa, M. H.; Ganguly, S.; Saatchi, S. S.; Nemani, R. R.; Myneni, R.

    2011-12-01

    A large increase in near-infrared (NIR) reflectance of Amazon forests during the light-rich dry season and a corresponding decrease during the light-poor wet season has been observed in satellite measurements. This has been variously interpreted as seasonal changes in leaf area resulting from net leaf flushing in the dry season and net leaf abscission in the wet season, enhanced photosynthetic activity during the dry season from flushing new leaves and as change in leaf scattering and absorption properties between younger and older leaves covered with epiphylls. Reconciling these divergent views using theory and observations is the goal of this article. The observed changes in NIR reflectance of Amazon forests could be due to similar, but small, changes in NIR leaf albedo (reflectance plus transmittance) only, from exchanging older leaves with newer ones, with total leaf area unchanged. However, this argument ignores accumulating evidence from ground-based studies of higher leaf area in the dry season relative to the wet season, seasonal changes in litterfall and does not satisfactorily explain why NIR reflectance of these forests decreases in the wet season. A more convincing explanation for the observed increase in NIR reflectance during the dry season and decrease during the wet season is one that invokes changes in both leaf area and leaf optical properties. Such an argument is consistent with known phonological behavior of tropical forests, ground-based reports of seasonal changes in leaf area, litterfall, leaf optical properties and fluxes of evapotranspiration, and thus, reconciles the various seemingly divergent views.

  20. Seasonal changes in leaf area of Amazon forests from leaf flushing and abscission

    NASA Astrophysics Data System (ADS)

    Samanta, Arindam; Knyazikhin, Yuri; Xu, Liang; Dickinson, Robert E.; Fu, Rong; Costa, Marcos H.; Saatchi, Sassan S.; Nemani, Ramakrishna R.; Myneni, Ranga B.

    2012-03-01

    A large increase in near-infrared (NIR) reflectance of Amazon forests during the light-rich dry season and a corresponding decrease during the light-poor wet season has been observed in satellite measurements. This increase has been variously interpreted as seasonal change in leaf area resulting from net leaf flushing in the dry season or net leaf abscission in the wet season, enhanced photosynthetic activity during the dry season from flushing new leaves and as change in leaf scattering and absorption properties between younger and older leaves covered with epiphylls. Reconciling these divergent views using theory and observations is the goal of this article. The observed changes in NIR reflectance of Amazon forests could be due to similar, but small, changes in NIR leaf albedo (reflectance plus transmittance) resulting from the exchange of older leaves for newer ones, but with the total leaf area unchanged. However, this argument ignores accumulating evidence from ground-based reports of higher leaf area in the dry season than the wet season, seasonal changes in litterfall and does not satisfactorily explain why NIR reflectance of these forests decreases in the wet season. More plausibly, the increase in NIR reflectance during the dry season and the decrease during the wet season would result from changes in both leaf area and leaf optical properties. Such change would be consistent with known phenological behavior of tropical forests, ground-based reports of seasonal changes in leaf area, litterfall, leaf optical properties and fluxes of evapotranspiration, and thus, would reconcile the various seemingly divergent views.

  1. The spatial extent of excitatory and inhibitory zones in the receptive field of superficial layer hypercomplex cells

    PubMed Central

    Sillito, A. M.

    1977-01-01

    1. An investigation has been made of the extent of inhibitory and excitatory components in the receptive field of superficial layer hypercomplex cells in the cat's striate cortex and the relation of the components to the length preference exhibited by these cells. 2. Maximal responses were produced by an optimal length stimulus moving through a restricted region of the receptive field. The length of this receptive field region was less than the total length of the excitatory zone as mapped with a very short slit. Slits of similar length to the excitatory zone produced a smaller response than an optimal length slit. 3. An increase of slit length so that it passed over receptive field regions either side of the excitatory zone resulted in an elimination of the response. When background discharge levels were increased by the iontophoretic application of D, L-homocysteic acid slits of this length were observed to produce a suppression of the resting discharge as they passed over the receptive field. They did not modify the resting discharge level when it was induced by the iontophoretic application of the GABA antagonist bicuculline. This data is taken to indicate that long slits activate a powerful post-synaptic inhibitory input to the cell. 4. Maximal inhibitory effects were only observed if the testing slit passed over the receptive field centre. That is slits with a gap positioned midway along their length so as to exclude the optimal excitatory response region surprisingly tended to produce excitatory effects rather than the expected inhibitory effects. It appears that simultaneous stimulation of the receptive field centre is a precondition for the inhibitory effect of stimulation of regions either side of the excitatory zone to be activated. 5. It is suggested that the interneurones mediating the inhibitory input to the superficial layer hypercomplex cells are driven both by cells in adjacent hypercolumns with receptive fields spatially displaced to either side

  2. DNA Microarray Gene Expression Profile of Marginal Zone versus Follicular B cells and Idiotype Positive Marginal Zone B cells Before and After Immunization with Streptococcus pneumoniae 1

    PubMed Central

    Liu, Jiabin; Behrens, Timothy W.; Kearney, John F.

    2014-01-01

    Marginal Zone (MZ) B cells play an important role in the clearance of blood-borne bacterial infections via rapid T-independent IgM responses. We have previously demonstrated that MZ B cells respond rapidly and robustly to bacterial particulates. To determine the MZ-specific genes that are expressed to allow for this response, MZ and Follicular (FO) B cells were sort-purified and analyzed via DNA microarray analysis. We identified 181 genes that were significantly different between the two B cell populations. 99 genes were more highly expressed in MZ B cells while 82 genes were more highly expressed in FO B cells. To further understand the molecular mechanisms by which MZ B cells respond so rapidly to bacterial challenge, idiotype positive and negative MZ B cells were sort-purified before (0 hour) or after (1 hour) i.v. immunization with heat killed Streptococcus pneumoniae, R36A, and analyzed via DNA microarray analysis. We identified genes specifically up regulated or down regulated at 1 hour following immunization in the idiotype positive MZ B cells. These results give insight into the gene expression pattern in resting MZ vs. FO B cells and the specific regulation of gene expression in antigen-specific MZ B cells following interaction with antigen. PMID:18453586

  3. Splenic marginal zone lymphoma.

    PubMed

    Piris, Miguel A; Onaindía, Arantza; Mollejo, Manuela

    Splenic marginal zone lymphoma (SMZL) is an indolent small B-cell lymphoma involving the spleen and bone marrow characterized by a micronodular tumoral infiltration that replaces the preexisting lymphoid follicles and shows marginal zone differentiation as a distinctive finding. SMZL cases are characterized by prominent splenomegaly and bone marrow and peripheral blood infiltration. Cells in peripheral blood show a villous cytology. Bone marrow and peripheral blood characteristic features usually allow a diagnosis of SMZL to be performed. Mutational spectrum of SMZL identifies specific findings, such as 7q loss and NOTCH2 and KLF2 mutations, both genes related with marginal zone differentiation. There is a striking clinical variability in SMZL cases, dependent of the tumoral load and performance status. Specific molecular markers such as 7q loss, p53 loss/mutation, NOTCH2 and KLF2 mutations have been found to be associated with the clinical variability. Distinction from Monoclonal B-cell lymphocytosis with marginal zone phenotype is still an open issue that requires identification of precise and specific thresholds with clinical meaning. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. The Expression Pattern of the Cell Cycle Inhibitor p19INK4d by Progenitor Cells of the Rat Embryonic Telencephalon and Neonatal Anterior Subventricular Zone

    PubMed Central

    Coskun, Volkan; Luskin, Marla B.

    2014-01-01

    In this study we investigated whether the pattern of expression of the cyclin-dependent kinase inhibitor p19INK4d by the unique progenitor cells of the neonatal anterior subventricular zone (SVZa) can account for their ability to divide even though they express phenotypic characteristics of differentiated neurons. p19INK4d was chosen for analysis because it usually acts to block permanently the cell cycle at the G1 phase. p19INK4d immunoreactivity and the incorporation of bromodeoxyuridine (BrdU) by SVZa cells were compared with that of the more typical progenitor cells of the prenatal telencephalic ventricular zone. In the developing telencephalon, p19INK4d is expressed by postmitotic cells and has a characteristic perinuclear distribution depending on the laminar position and state of differentiation of a cell. Moreover, the laminar-specific staining of the developing cerebral cortex revealed that the ventricular zone (VZ) is divided into p19INK4d(+) and p19INK4d(−) sublaminae, indicating that the VZ has a previously unrecognized level of functional organization. Furthermore, the rostral migratory stream, traversed by the SVZa-derived cells, exhibits an anteriorhigh–posteriorlow gradient of p19INK4d expression. On the basis of the p19INK4d immunoreactivity and BrdU incorporation, SVZa-derived cells appear to exit and reenter the cell cycle successively. Thus, in contrast to telencephalic VZ cells, SVZa cells continue to undergo multiple rounds of division and differentiation before becoming postmitotic. PMID:11312294

  5. The ciliary margin zone of the mammalian retina generates retinal ganglion cells

    PubMed Central

    Marcucci, Florencia; Murcia-Belmonte, Veronica; Coca, Yaiza; Ferreiro-Galve, Susana; Wang, Qing; Kuwajima, Takaaki; Khalid, Sania; Ross, M. Elizabeth; Herrera, Eloisa; Mason, Carol

    2016-01-01

    Summary The retina of lower vertebrates grows continuously by integrating new neurons generated from progenitors in the ciliary margin zone (CMZ). Whether the mammalian CMZ provides the neural retina with retinal cells is controversial. Live-imaging of embryonic retina expressing eGFP in the CMZ shows that cells migrate laterally from the CMZ to the neural retina where differentiated retinal ganglion cells (RGCs) reside. As Cyclin D2, a cell-cycle regulator, is enriched in ventral CMZ, we analyzed Cyclin D2−/− mice to test whether the CMZ is a source of retinal cells. Neurogenesis is diminished in Cyclin D2 mutants, leading to a reduction of RGCs in the ventral retina. In line with these findings, in the albino retina, the decreased production of ipsilateral RGCs is correlated with fewer Cyclin D2+ cells. Together, these results implicate the mammalian CMZ as a neurogenic site that produces RGCs and whose proper generation depends on Cyclin D2 activity. PMID:28009286

  6. Pathology of nodal marginal zone lymphomas.

    PubMed

    Pileri, Stefano; Ponzoni, Maurilio

    Nodal marginal zone B cell lymphomas (NMZLs) are a rare group of lymphoid disorders part of the spectrum of marginal zone B-cell lymphomas, which encompass splenic marginal one B-cell lymphoma (SMZL) and extra nodal marginal zone of B-cell lymphoma (EMZL), often of MALT-type. Two clinicopathological forms of NMZL are recognized: adult-type and pediatric-type, respectively. NMZLs show overlapping features with other types of MZ, but distinctive features as well. In this review, we will focus on the salient distinguishing features of NMZL mostly under morphological/immunophenotypical/molecular perspectives in views of the recent acquisitions and forthcoming updated 2016 WHO classification of lymphoid malignancies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Progenitor cells from different zones of human cartilage and their correlation with histopathological osteoarthritis progression.

    PubMed

    Mantripragada, Venkata P; Bova, Wesley A; Boehm, Cynthia; Piuzzi, Nicolas S; Obuchowski, Nancy A; Midura, Ronald J; Muschler, George F

    2018-06-01

    Cell-based therapies development for the treatment of osteoarthritis (OA) requires an understanding of the disease progression and attributes of the cells resident in cartilage. This study focused on quantitative assessment of the concentration and biological potential of stem and progenitor cells resident in different zones of cartilage displaying macroscopic Outerbridge grade 1-2 OA, and their correlation with OA progression based on established histologic scoring system. Lateral femoral condyles were collected from 15 patients with idiopathic OA and varus knees undergoing total knee arthroplasty. Superficial(C sp , top ∼ 500 µm) and deep cartilage(C dp ) was separated. Chondrogenic Connective Tissue Progenitors (CTP-C) were assayed by standardized Colony-Forming-Unit assay using automated image analysis (Colonyze TM ) based on ASTM standard F-2944-12. Cell concentration (cells/mg) was significantly greater in C sp (median: 7,000; range: 3,440-17,600) than C dp (median: 5,340; range: 3,393-9,660), p = 0.039. Prevalence (CTPs/million cells) was not different between C sp (median: 1,274; range: 0-3,898) and C dp (median:1,365; range:0-6,330), p = 0.42. In vitro performance of CTP-C progeny varied widely within and between patients, manifest by variation in colony size and morphology. Mean histopathological Mankin score was 4.7 (SD = 1.2), representing mild to moderate OA. Tidemark breach by blood vessels was associated with lower C sp cell concentration (p = 0.02). Matrix degradation was associated with lower C dp cell and CTP-C concentration (p = 0.015 and p = 0.095, respectively), independent of articular surface changes. These findings suggest that the initiation of OA may occur in either superficial or deep zones. The pathological changes affect CTP-Cs in C sp and C dp cartilage zones differently. The heterogeneity among the available CTP-Cs in C sp and C dp suggests performance-based selection to optimize cell

  8. Blood dendritic cells interact with splenic marginal zone B cells to initiate T-independent immune responses.

    PubMed

    Balázs, Mercedesz; Martin, Flavius; Zhou, Tong; Kearney, John

    2002-09-01

    Marginal zone (MZ) and B1 B lymphocytes participate jointly in the early immune response against T-independent (TI) particulate antigens. Here we show that blood-derived neutrophil granulocytes and CD11c(lo) immature dendritic cells (DC) are the primary cells that efficiently capture and transport particulate bacteria to the spleen. In a systemic infection, CD11c(lo) DC, but not neutrophils, provide critical survival signals, which can be inhibited by TACI-Fc, to antigen-specific MZ B cells and promote their differentiation into IgM-secreting plasmablasts. In a local TI response, peritoneal cavity macrophages provide similar support to B1 B-derived Ag-specific blasts. In the absence of soluble TACI ligands, Ag-activated MZ- and B1-derived blasts lack survival signals and undergo apoptosis, resulting in severely impaired antibody responses.

  9. How PI3K-derived lipids control cell division.

    PubMed

    Campa, Carlo C; Martini, Miriam; De Santis, Maria C; Hirsch, Emilio

    2015-01-01

    To succeed in cell division, intense cytoskeletal and membrane remodeling are required to allow accurate chromosome segregation and cytoplasm partitioning. Spatial restriction of the actin dynamics and vesicle trafficking define the cell symmetry and equivalent membrane scission events, respectively. Protein complexes coordinating mitosis are recruited to membrane microdomains characterized by the presence of the phosphatidylinositol lipid members (PtdIns), like PtdIns(3,4,5)P 3,PtdIns(4,5)P 2, and PtdIns(3)P. These PtdIns represent a minor component of cell membranes, defining membrane domain identity, ultimately controlling cytoskeleton and membrane dynamics during mitosis. The coordinated presence of PtdIns(3,4,5)P 3 at the cell poles and PtdIns(4,5)P 2 at the cleavage furrow controls the polarity of the actin cytoskeleton leading to symmetrical cell division. In the endosomal compartment, the trafficking of PtdIns(3)P positive vesicles allows the recruitment of the protein machinery required for the abscission.

  10. An Anatomical Assessment of Branch Abscission and Branch-base Hydraulic Architecture in the Endangered Wollemia nobilis

    PubMed Central

    Burrows, G. E.; Meagher, P. F.; Heady, R. D.

    2007-01-01

    Background and Aims The branch-base xylem structure of the endangered Wollemia nobilis was anatomically investigated. Wollemia nobilis is probably the only extant tree species that produces only first-order branches and where all branches are cleanly abscised. An investigation was carried out to see if these unusual features might influence branch-base xylem structure and water supply to the foliage. Methods The xylem was sectioned at various distances along the branch bases of 6-year-old saplings. Huber values and relative theoretical hydraulic conductivities were calculated for various regions of the branch base. Key Results The most proximal branch base featured a pronounced xylem constriction. The constriction had only 14–31 % (average 21 %) of the cross-sectional area and 20–42 % (average 28 %) of the theoretical hydraulic conductivity of the more distal branch xylem. Wollemia nobilis had extremely low Huber values for a conifer. Conclusions The branch-base xylem constriction would appear to facilitate branch abscission, while the associated Huber values show that W. nobilis supplies a relatively large leaf area through a relatively small diameter ‘pipe’. It is tempting to suggest that the pronounced decline of W. nobilis in the Tertiary is related to its unusual branch-base structure but physiological studies of whole plant conductance are still needed. PMID:17272303

  11. The Ciliary Margin Zone of the Mammalian Retina Generates Retinal Ganglion Cells.

    PubMed

    Marcucci, Florencia; Murcia-Belmonte, Veronica; Wang, Qing; Coca, Yaiza; Ferreiro-Galve, Susana; Kuwajima, Takaaki; Khalid, Sania; Ross, M Elizabeth; Mason, Carol; Herrera, Eloisa

    2016-12-20

    The retina of lower vertebrates grows continuously by integrating new neurons generated from progenitors in the ciliary margin zone (CMZ). Whether the mammalian CMZ provides the neural retina with retinal cells is controversial. Live imaging of embryonic retina expressing eGFP in the CMZ shows that cells migrate laterally from the CMZ to the neural retina where differentiated retinal ganglion cells (RGCs) reside. Because Cyclin D2, a cell-cycle regulator, is enriched in ventral CMZ, we analyzed Cyclin D2 -/- mice to test whether the CMZ is a source of retinal cells. Neurogenesis is diminished in Cyclin D2 mutants, leading to a reduction of RGCs in the ventral retina. In line with these findings, in the albino retina, the decreased production of ipsilateral RGCs is correlated with fewer Cyclin D2 + cells. Together, these results implicate the mammalian CMZ as a neurogenic site that produces RGCs and whose proper generation depends on Cyclin D2 activity. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Fission yeast Ags1 confers the essential septum strength needed for safe gradual cell abscission

    PubMed Central

    Sato, Mamiko; Muñoz, Javier; Moreno, M. Belén; Clemente-Ramos, Jose Angel; Ramos, Mariona; Okada, Hitoshi; Osumi, Masako; Durán, Angel; Ribas, Juan Carlos

    2012-01-01

    Fungal cytokinesis requires the assembly of a dividing septum wall. In yeast, the septum has to be selectively digested during the critical cell separation process. Fission yeast cell wall α(1-3)glucan is essential, but nothing is known about its localization and function in the cell wall or about cooperation between the α- and β(1-3)glucan synthases Ags1 and Bgs for cell wall and septum assembly. Here, we generate a physiological Ags1-GFP variant and demonstrate a tight colocalization with Bgs1, suggesting a cooperation in the important early steps of septum construction. Moreover, we define the essential functions of α(1-3)glucan in septation and cell separation. We show that α(1-3)glucan is essential for both secondary septum formation and the primary septum structural strength needed to support the physical forces of the cell turgor pressure during cell separation. Consequently, the absence of Ags1 and therefore α(1-3)glucan generates a special and unique side-explosive cell separation due to an instantaneous primary septum tearing caused by the turgor pressure. PMID:22891259

  13. Dynamic hydrostatic pressure enhances differentially the chondrogenesis of meniscal cells from the inner and outer zone.

    PubMed

    Zellner, J; Mueller, M; Xin, Y; Krutsch, W; Brandl, A; Kujat, R; Nerlich, M; Angele, P

    2015-06-01

    This study analyses the influence of dynamic hydrostatic pressure on chondrogenesis of human meniscus-derived fibrochondrocytes and explores the differences in chondrogenic differentiation under loading conditions between cells derived from the avascular inner zone and vascularized outer region of the meniscus. Aggregates of human fibrochondrocytes with cell origin from the inner region or with cell origin from the outer region were generated. From the two groups of either cell origin, aggregates were treated with dynamic hydrostatic pressure (1Hz for 4h; 0.55-5.03MPa, cyclic sinusoidal) from day 1 to day 7. The other aggregates served as unloaded controls. At day 0, 7, 14 and 21 aggregates were harvested for evaluation including histology, immunostaining and ELISA analysis for glycosaminoglycan (GAG) and collagen II. Loaded aggregates were found to be macroscopically larger and revealed immunohistochemically enhanced chondrogenesis compared to the corresponding controls. Loaded or non-loaded meniscal cells from the outer zone showed a higher potential and earlier onset of chondrogenesis compared to the cells from the inner part of the meniscus. This study suggests that intrinsic factors like cell properties in the different areas of the meniscus and their reaction on mechanical load might play important roles in designing Tissue Engineering strategies for meniscal repair in vivo. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. The Endocytic Adaptor Eps15 Controls Marginal Zone B Cell Numbers

    PubMed Central

    Pozzi, Benedetta; Amodio, Stefania; Lucano, Caterina; Sciullo, Anna; Ronzoni, Simona; Castelletti, Daniela; Adler, Thure; Treise, Irina; Betsholtz, Ingrid Holmberg; Rathkolb, Birgit; Busch, Dirk H.; Wolf, Eckhard; Fuchs, Helmut; Gailus-Durner, Valérie; de Angelis, Martin Hrabě; Betsholtz, Christer; Casola, Stefano; Di Fiore, Pier Paolo; Offenhäuser, Nina

    2012-01-01

    Eps15 is an endocytic adaptor protein involved in clathrin and non-clathrin mediated endocytosis. In Caenorhabditis elegans and Drosophila melanogaster lack of Eps15 leads to defects in synaptic vesicle recycling and synapse formation. We generated Eps15-KO mice to investigate its function in mammals. Eps15-KO mice are born at the expected Mendelian ratio and are fertile. Using a large-scale phenotype screen covering more than 300 parameters correlated to human disease, we found that Eps15-KO mice did not show any sign of disease or neural deficits. Instead, altered blood parameters pointed to an immunological defect. By competitive bone marrow transplantation we demonstrated that Eps15-KO hematopoietic precursor cells were more efficient than the WT counterparts in repopulating B220+ bone marrow cells, CD19− thymocytes and splenic marginal zone (MZ) B cells. Eps15-KO mice showed a 2-fold increase in MZ B cell numbers when compared with controls. Using reverse bone marrow transplantation, we found that Eps15 regulates MZ B cell numbers in a cell autonomous manner. FACS analysis showed that although MZ B cells were increased in Eps15-KO mice, transitional and pre-MZ B cell numbers were unaffected. The increase in MZ B cell numbers in Eps15 KO mice was not dependent on altered BCR signaling or Notch activity. In conclusion, in mammals, the endocytic adaptor protein Eps15 is a regulator of B-cell lymphopoiesis. PMID:23226392

  15. [Changes of lastids in virus-infected cells of the attraction-zone from Sarracenia purpurea L].

    PubMed

    Barckhaus, R H; Weinert, H

    1975-01-01

    Viruslike particles 300-350 nm long and 70 nm in diameter were found in ultrathin sections of attraction-zone from Sarracenia purpurea. Epidermal- and mesophyll cells contained the bacilliform particles. The membrane-bound particles-most virions occured within ER-like membranes-consisted of an outer coat 70-90 A thick, an inner membrane and an axial core. The plastids of infected cells in which virus particles were localized show morphologicals changes of the organells.

  16. Cell and matrix modulation in prenatal and postnatal equine growth cartilage, zones of Ranvier and articular cartilage

    PubMed Central

    Löfgren, Maria; Ekman, Stina; Svala, Emilia; Lindahl, Anders; Ley, Cecilia; Skiöldebrand, Eva

    2014-01-01

    Formation of synovial joints includes phenotypic changes of the chondrocytes and the organisation of their extracellular matrix is regulated by different factors and signalling pathways. Increased knowledge of the normal processes involved in joint development may be used to identify similar regulatory mechanisms during pathological conditions in the joint. Samples of the distal radius were collected from prenatal and postnatal equine growth plates, zones of Ranvier and articular cartilage with the aim of identifying Notch signalling components and cells with stem cell-like characteristics and to follow changes in matrix protein localisation during joint development. The localisation of the Notch signalling components Notch1, Delta4, Hes1, Notch dysregulating protein epidermal growth factor-like domain 7 (EGFL7), the stem cell-indicating factor Stro-1 and the matrix molecules cartilage oligomeric matrix protein (COMP), fibromodulin, matrilin-1 and chondroadherin were studied using immunohistochemistry. Spatial changes in protein localisations during cartilage maturation were observed for Notch signalling components and matrix molecules, with increased pericellular localisation indicating new synthesis and involvement of these proteins in the formation of the joint. However, it was not possible to characterise the phenotype of the chondrocytes based on their surrounding matrix during normal chondrogenesis. The zone of Ranvier was identified in all horses and characterised as an area expressing Stro-1, EGFL7 and chondroadherin with an absence of COMP and Notch signalling. Stro-1 was also present in cells close to the perichondrium, in the articular cartilage and in the fetal resting zone, indicating stem cell-like characteristics of these cells. The presence of stem cells in the articular cartilage will be of importance for the repair of damaged cartilage. Perivascular chondrocytes and hypertrophic cells of the cartilage bone interface displayed positive staining for

  17. Germinal zones in the developing cerebral cortex of ferret: ontogeny, cell cycle kinetics, and diversity of progenitors.

    PubMed

    Reillo, Isabel; Borrell, Víctor

    2012-09-01

    Expansion and folding of the cerebral cortex are landmark features of mammalian brain evolution. This is recapitulated during embryonic development, and specialized progenitor cell populations known as intermediate radial glia cells (IRGCs) are believed to play central roles. Because developmental mechanisms involved in cortical expansion and folding are likely conserved across phylogeny, it is crucial to identify features specific for gyrencephaly from those unique to primate brain development. Here, we studied multiple features of cortical development in ferret, a gyrencephalic carnivore, in comparison with primates. Analyzing the combinatorial expression of transcription factors, cytoskeletal proteins, and cell cycle parameters, we identified a combination of traits that distinguish in ferret similar germinal layers as in primates. Transcription factor analysis indicated that inner subventricular zone (ISVZ) and outer subventricular zone (OSVZ) may contain an identical mixture of progenitor cell subpopulations in ferret. However, we found that these layers emerge at different time points, differ in IRGC abundance, and progenitors have different cell cycle kinetics and self-renewal dynamics. Thus, ISVZ and OSVZ are likely distinguished by genetic differences regulating progenitor cell behavior and dynamics. Our findings demonstrate that some, but not all, features of primate cortical development are shared by the ferret, suggesting a conserved role in the evolutionary emergence of gyrencephaly.

  18. Abnormal Labyrinthine Zone in the Hectd1-null Placenta

    PubMed Central

    Sarkar, Anjali A.; Sabatino, Julia A.; Sugrue, Kelsey F.; Zohn, Irene E.

    2016-01-01

    Introduction The labyrinthine zone of the placenta is where exchange of nutrients and waste occurs between maternal and fetal circulations. Proper development of the placental labyrinth is essential for successful growth of the developing fetus and abnormalities in placental development are associated with intrauterine growth restriction (IUGR), preeclampsia and fetal demise. Our previous studies demonstrate that Hectd1 is essential for development of the junctional and labyrinthine zones of the placenta. Here we further characterize labyrinthine zone defects in the Hectd1 mutant placenta. Methods The structure of the mutant placenta was compared to wildtype littermates using histological methods. The expression of cell type specific markers was examined by immunohistochemistry and in situ hybridization. Results Hectd1 is expressed in the labyrinthine zone throughout development and the protein is enriched in syncytiotrophoblast layer type I cells (SynT-I) and Sinusoidal Trophoblast Giant cells (S-TGCs) in the mature placenta. Mutation of Hectd1 results in pale placentas with frequent hemorrhages along with gross abnormalities in the structure of the labyrinthine zone including a smaller overall volume and a poorly elaborated fetal vasculature that contain fewer fetal blood cells. Examination of molecular markers of labyrinthine trophoblast cell types reveals increased Dlx3 positive cells and Syna positive SynT-I cells, along with decreased Hand1 and Ctsq positive sinusoidal trophoblast giant cells (S-TGCs). Discussion Together these defects indicate that Hectd1 is required for development of the labyrinthine zone or the mouse placenta. PMID:26907377

  19. Adult subventricular zone neural stem cells as a potential source of dopaminergic replacement neurons

    PubMed Central

    Cave, John W.; Wang, Meng; Baker, Harriet

    2014-01-01

    Clinical trials engrafting human fetal ventral mesencephalic tissue have demonstrated, in principle, that cell replacement therapy provides substantial long-lasting improvement of motor impairments generated by Parkinson's Disease (PD). The use of fetal tissue is not practical for widespread clinical implementation of this therapy, but stem cells are a promising alternative source for obtaining replacement cells. The ideal stem cell source has yet to be established and, in this review, we discuss the potential of neural stem cells in the adult subventricular zone (SVZ) as an autologous source of replacement cells. We identify three key challenges for further developing this potential source of replacement cells: (1) improving survival of transplanted cells, (2) suppressing glial progenitor proliferation and survival, and (3) developing methods to efficiently produce dopaminergic neurons. Subventricular neural stem cells naturally produce a dopaminergic interneuron phenotype that has an apparent lack of vulnerability to PD-mediated degeneration. We also discuss whether olfactory bulb dopaminergic neurons derived from adult SVZ neural stem cells are a suitable source for cell replacement strategies. PMID:24574954

  20. Calcium-dependent depletion zones in the cortical microtubule array coincide with sites of, but do not regulate, wall ingrowth papillae deposition in epidermal transfer cells

    PubMed Central

    Zhang, Hui-ming; Talbot, Mark J.; McCurdy, David W.; Patrick, John W.; Offler, Christina E.

    2015-01-01

    Trans-differentiation to a transfer-cell morphology is characterized by the localized deposition of wall ingrowth papillae that protrude into the cytosol. Whether the cortical microtubule array directs wall ingrowth papillae formation was investigated using a Vicia faba cotyledon culture system in which their adaxial epidermal cells were spontaneously induced to trans-differentiate to transfer cells. During deposition of wall ingrowth papillae, the aligned cortical microtubule arrays in precursor epidermal cells were reorganized into a randomized array characterized by circular depletion zones. Concurrence of the temporal appearance, spatial pattern, and size of depletion zones and wall ingrowth papillae was consistent with each papilla occupying a depletion zone. Surprisingly, microtubules appeared not to regulate construction of wall ingrowth papillae, as neither depolymerization nor stabilization of cortical microtubules changed their deposition pattern or morphology. Moreover, the size and spatial pattern of depletion zones was unaltered when the formation of wall ingrowth papillae was blocked by inhibiting cellulose biosynthesis. In contrast, the depletion zones were absent when the cytosolic calcium plumes, responsible for directing wall ingrowth papillae formation, were blocked or dissipated. Thus, we conclude that the depletion zones within the cortical microtubule array result from localized depolymerization of microtubules initiated by elevated cytosolic Ca2+ levels at loci where wall ingrowth papillae are deposited. The physiological significance of the depletion zones as a mechanism to accommodate the construction of wall ingrowth papillae without compromising maintenance of the plasma membrane–microtubule inter-relationship is discussed. PMID:26136268

  1. Cell Wall Pectin and its Methyl-esterification in Transition Zone Determine Al Resistance in Cultivars of Pea (Pisum sativum)

    PubMed Central

    Li, Xuewen; Li, Yalin; Qu, Mei; Xiao, Hongdong; Feng, Yingming; Liu, Jiayou; Wu, Lishu; Yu, Min

    2016-01-01

    The initial response of plants to aluminum (Al) is the inhibition of root elongation, while the transition zone is the most Al sensitive zone in the root apex, which may sense the presence of Al and regulate the responses of root to Al toxicity. In the present study, the effect of Al treatment (30 μM, 24 h) on root growth, Al accumulation, and properties of cell wall of two pea (Pisum sativum L.) cultivars, cv Onward (Al-resistant) and cv Sima (Al-sensitive), were studied to disclose whether the response of root transition zone to Al toxicity determines Al resistance in pea cultivars. The lower relative root elongation (RRE) and higher Al content were founded in cv Sima compared with cv Onward, which were related to Al-induced the increase of pectin in root segments of both cultivars. The increase of pectin is more prominent in Al-sensitive cultivar than in Al-resistant cultivar. Aluminum toxicity also induced the increase of pectin methylesterases (PME), which is 2.2 times in root transition zone in Al-sensitive cv Sima to that of Al resistant cv Onward, thus led to higher demethylesterified pectin content in root transition zone of Al-sensitive cv Sima. The higher demethylesterified pectin content in root transition zone resulted in more Al accumulation in the cell wall and cytosol in Al-sensitive cv Sima. Our results provide evidence that the increase of pectin content and PME activity under Al toxicity cooperates to determine Al sensitivity in root transition zone that confers Al resistance in cultivars of pea (Pisum sativum). PMID:26870060

  2. Calcium-dependent depletion zones in the cortical microtubule array coincide with sites of, but do not regulate, wall ingrowth papillae deposition in epidermal transfer cells.

    PubMed

    Zhang, Hui-ming; Talbot, Mark J; McCurdy, David W; Patrick, John W; Offler, Christina E

    2015-09-01

    Trans-differentiation to a transfer-cell morphology is characterized by the localized deposition of wall ingrowth papillae that protrude into the cytosol. Whether the cortical microtubule array directs wall ingrowth papillae formation was investigated using a Vicia faba cotyledon culture system in which their adaxial epidermal cells were spontaneously induced to trans-differentiate to transfer cells. During deposition of wall ingrowth papillae, the aligned cortical microtubule arrays in precursor epidermal cells were reorganized into a randomized array characterized by circular depletion zones. Concurrence of the temporal appearance, spatial pattern, and size of depletion zones and wall ingrowth papillae was consistent with each papilla occupying a depletion zone. Surprisingly, microtubules appeared not to regulate construction of wall ingrowth papillae, as neither depolymerization nor stabilization of cortical microtubules changed their deposition pattern or morphology. Moreover, the size and spatial pattern of depletion zones was unaltered when the formation of wall ingrowth papillae was blocked by inhibiting cellulose biosynthesis. In contrast, the depletion zones were absent when the cytosolic calcium plumes, responsible for directing wall ingrowth papillae formation, were blocked or dissipated. Thus, we conclude that the depletion zones within the cortical microtubule array result from localized depolymerization of microtubules initiated by elevated cytosolic Ca(2+) levels at loci where wall ingrowth papillae are deposited. The physiological significance of the depletion zones as a mechanism to accommodate the construction of wall ingrowth papillae without compromising maintenance of the plasma membrane-microtubule inter-relationship is discussed. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  3. Toxicity of Chlorpyrifos and Dimethoate to the Ciliate Urostyla grandis, with Notes on Their Effects on Cell Ultrastructure

    NASA Astrophysics Data System (ADS)

    Mu, Weijie; Warren, Alan; Pan, Xuming; Ying, Chen

    2018-06-01

    Chlorpyrifos and dimethoate are overused agricultural pesticides that can trigger trophic cascades, resulting in toxicity to both terrestrial and aquatic organisms as well as altered ecosystems. In previous studies, substantial attention has been given to the effects of pesticides on vertebrate species and, to a lesser extent, species of zooplankton. The present study was designed to show that the fission time effective concentration in ciliates is a potential aquatic detection index for environmental monitoring. The ciliate Urostyla grandis was treated with doses of chlorpyrifos and dimethoate. After exposed to the pesticides, the LC 50 ( i.e., concentration that killed 50% of the ciliate cells within 24 h) values were 0.029 mg L-1 for chlorpyrifos and 0.0685 mg L-1 for dimethoate. The fission time effective concentrations after 168 h of exposure were 0.0075-0.0093 mg L-1 for chlorpyrifos and 0.2640-0.2750 mg L-1 for dimethoate. These results show that the fission time effective concentration is lower than the LC 50 value in ciliates, indicating that fission time effective concentration is more suitable than the LC 50 value for environmental monitoring using ciliates. The effects of chlorpyrifos and dimethoate on ciliate cell ultrastructures included agglutination of chromatin in the macronucleus, protruded and discontinuous macronuclear and micronuclear membranes, loss of integrity of mitochondrial membranes and contents, and abscission and deformation of the adoral zone of membranelles.

  4. Zone-specific cell biosynthetic activity in mature bovine articular cartilage: a new method using confocal microscopic stereology and quantitative autoradiography.

    PubMed

    Wong, M; Wuethrich, P; Eggli, P; Hunziker, E

    1996-05-01

    A new methodology was developed to measure spatial variations in chondrocyte/matrix structural parameters and chondrocyte biosynthetic activity in articular cartilage. This technique is based on the use of a laser scanning confocal microscope that can "optically" section chemically fixed, unembedded tissue. The confocal images are used for morphometric measurement of stereologic parameters such as cell density (cells/mm3), cell volume fraction (%), surface density (l/cm), mean cell volume (micron3), and mean cell surface area (micron2). Adjacent pieces of tissue are simultaneously processed for conventional liquid emulsion autoradiography, and a semiautomated grain counting program is used to measure the silver grain density at regions corresponding to the same sites used for structural measurements. An estimate of chondrocyte biosynthetic activity in terms of grains per cell is obtained by dividing the value for grain density by that for cell density. In this paper, the newly developed methodology was applied to characterize the zone-specific behavior of adult articular cartilage in the free-swelling state. Cylinders of young adult bovine articular cartilage were labelled with either [3H]proline or [35S]sulfate, and chondrocyte biosynthesis and structural parameters were measured from the articular surface to the tidemark. The results showed that chondrocytes of the radial zone occupied twice the volume and surface area of the chondrocytes of the superficial zone but were 10 times more synthetically active. This efficient and unbiased technique may prove useful in studying the correlation between mechanically induced changes in cell form and biosynthetic activity within inhomogeneous tissue as well as metabolic changes in cartilage due to ageing and disease.

  5. Abnormal labyrinthine zone in the Hectd1-null placenta.

    PubMed

    Sarkar, Anjali A; Sabatino, Julia A; Sugrue, Kelsey F; Zohn, Irene E

    2016-02-01

    The labyrinthine zone of the placenta is where exchange of nutrients and waste occurs between maternal and fetal circulations. Proper development of the placental labyrinth is essential for successful growth of the developing fetus and abnormalities in placental development are associated with intrauterine growth restriction (IUGR), preeclampsia and fetal demise. Our previous studies demonstrate that Hectd1 is essential for development of the junctional and labyrinthine zones of the placenta. Here we further characterize labyrinthine zone defects in the Hectd1 mutant placenta. The structure of the mutant placenta was compared to wildtype littermates using histological methods. The expression of cell type specific markers was examined by immunohistochemistry and in situ hybridization. Hectd1 is expressed in the labyrinthine zone throughout development and the protein is enriched in syncytiotrophoblast layer type I cells (SynT-I) and Sinusoidal Trophoblast Giant cells (S-TGCs) in the mature placenta. Mutation of Hectd1 results in pale placentas with frequent hemorrhages along with gross abnormalities in the structure of the labyrinthine zone including a smaller overall volume and a poorly elaborated fetal vasculature that contain fewer fetal blood cells. Examination of molecular markers of labyrinthine trophoblast cell types reveals increased Dlx3 positive cells and Syna positive SynT-I cells, along with decreased Hand1 and Ctsq positive sinusoidal trophoblast giant cells (S-TGCs). Together these defects indicate that Hectd1 is required for development of the labyrinthine zonethe mouse placenta. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Changes of vessel-cells complex in zones of adaptive remodeling of the bone tissue under microgravity conditions

    NASA Astrophysics Data System (ADS)

    Rodionova, N.; Oganov, V.; Nosova, L.

    The development and differentiation of osteogenic cells in organism happen in closely topographical and functional connection with blood capillaries. We formerly proofed, that small-differentiated cells, which are in the population of perivascular cells are osteogenic cells -precursors . At the present time it is actually to clear up, how these biostructures react on conditions of less of biomechanical load on skeleton bones. We researched peculiarities of blood-bed structure and perivascular cells in metaphises of thighbones and tibial bones in rats, which were onboard the American space station SLS-2 and in experiments of modeling hypokinesia. There were used methods of cytochemistry, histology and electron microscopy. We established, that under the support and functional load decreasing in zones of bones adaptive remodeling, comparatively to control, on histosections the own volume of sinusoid capillaries reduces. The small vessels prevail here. The spaces of sinusoid capillaries are limited by 1 2 cells of the endothelia. Endotheliocytes in- general have the typical ultrastructure. Basal membranes are expressed not-distinctly. Perivascular cells don't create the unbroken layer. The population of these cells is not-homogeneous. It includes enclosed to endothelia small-differentiated forms and separating cells with sings of fibroblastic differentiation (the own volume of rough endoplasmic reticulum in cytoplasm induces). The part of these cells reacts on the alkaline phosphatase (the marker of the osteogenic differentiation). Under the conditions of support load decreasing (especially under the microgravity) there is a tendency to reducing of separating osteogenic cells number. We noted the priority of differentiating fibroblasts. It leads to further development in zones of bone remodeling of hearths of fibrous tissue, that doesn't mineralize. The obtained data are seen as one of mechanisms of osteoporosis and osteopenia development under the deficite of support

  7. Proliferation zones in the axolotl brain and regeneration of the telencephalon.

    PubMed

    Maden, Malcolm; Manwell, Laurie A; Ormerod, Brandi K

    2013-01-17

    Although the brains of lower vertebrates are known to exhibit somewhat limited regeneration after incisional or stab wounds, the Urodele brain exhibits extensive regeneration after massive tissue removal. Discovering whether and how neural progenitor cells that reside in the ventricular zones of Urodeles proliferate to mediate tissue repair in response to injury may produce novel leads for regenerative strategies. Here we show that endogenous neural progenitor cells resident to the ventricular zone of Urodeles spontaneously proliferate, producing progeny that migrate throughout the telencephalon before terminally differentiating into neurons. These progenitor cells appear to be responsible for telencephalon regeneration after tissue removal and their activity may be up-regulated by injury through an olfactory cue. There is extensive proliferation of endogenous neural progenitor cells throughout the ventricular zone of the adult axolotl brain. The highest levels are observed in the telencephalon, especially the dorsolateral aspect, and cerebellum. Lower levels are observed in the mesencephalon and rhombencephalon. New cells produced in the ventricular zone migrate laterally, dorsally and ventrally into the surrounding neuronal layer. After migrating from the ventricular zone, the new cells primarily express markers of neuronal differentiative fates. Large-scale telencephalic tissue removal stimulates progenitor cell proliferation in the ventricular zone of the damaged region, followed by proliferation in the tissue that surrounds the healing edges of the wound until the telencephalon has completed regeneration. The proliferative stimulus appears to reside in the olfactory system, because telencephalic regeneration does not occur in the brains of olfactory bulbectomized animals in which the damaged neural tissue simply heals over. There is a continual generation of neuronal cells from neural progenitor cells located within the ventricular zone of the axolotl brain

  8. Emerging role of infectious etiologies in the pathogenesis of marginal zone B-cell lymphomas.

    PubMed

    Zucca, Emanuele; Bertoni, Francesco; Vannata, Barbara; Cavalli, Franco

    2014-10-15

    Extranodal marginal zone B-cell lymphomas of the mucosa-associated lymphoid tissue (MALT) arise from lymphoid populations that are induced by chronic inflammation in extranodal sites. The most frequently affected organ is the stomach, where MALT lymphoma is incontrovertibly associated with a chronic gastritis induced by a microbial pathogen, Helicobacter pylori. Gastric MALT lymphoma therefore represents a paradigm for evaluating inflammation-associated lymphomagenesis, which may lead to a deeper understanding of a possible etiologic association between other microorganisms and nongastric marginal zone lymphomas. Besides infectious etiology, chronic inflammation caused by autoimmune diseases, such as Sjögren syndrome or Hashimoto thyroiditis, can also carry a significant risk factor for the development of marginal zone lymphoma. In addition to the continuous antigenic drive, additional oncogenic events play a relevant role in lymphoma growth and progression to the point at which the lymphoproliferative process may eventually become independent of antigenic stimulation. Recent studies on MALT lymphomas have in fact demonstrated genetic alterations affecting the NF-κB) pathway, a major signaling pathway involved in many cancers. This review aims to present marginal zone lymphoma as an example of the close pathogenetic link between chronic inflammation and tumor development, with particular attention to the role of infectious agents and the integration of these observations into everyday clinical practice. See all articles in this CCR Focus section, "Paradigm Shifts in Lymphoma." ©2014 American Association for Cancer Research.

  9. Success of chemolithoautotrophic SUP05 and Sulfurimonas GD17 cells in pelagic Baltic Sea redox zones is facilitated by their lifestyles as K- and r-strategists.

    PubMed

    Rogge, Andreas; Vogts, Angela; Voss, Maren; Jürgens, Klaus; Jost, Günter; Labrenz, Matthias

    2017-06-01

    Chemolithoautotrophic sulfur-oxidizing and denitrifying Gamma- (particularly the SUP05 cluster) and Epsilonproteobacteria (predominantly Sulfurimonas subgroup GD17) are assumed to compete for substrates (electron donors and acceptors) in marine pelagic redox gradients. To elucidate their ecological niche separation we performed 34 S 0 , 15 NO3- and H 13 CO3- stable-isotope incubations with water samples from Baltic Sea suboxic, chemocline and sulfidic zones followed by combined phylogenetic staining and high-resolution secondary ion mass spectrometry of single cells. SUP05 cells were small-sized (0.06-0.09 µm 3 ) and most abundant in low-sulfidic to suboxic zones, whereas Sulfurimonas GD17 cells were significantly larger (0.26-0.61 µm 3 ) and most abundant at the chemocline and below. Together, SUP05 and GD17 cells accumulated up to 48% of the labelled substrates but calculation of cell volume-specific rates revealed that GD17 cells incorporated labelled substrates significantly faster throughout the redox zone, thereby potentially outcompeting SUP05 especially at high substrate concentrations. Thus, in synopsis with earlier described features of SUP05/GD17 we conclude that their spatially overlapping association in stratified sulfidic zones is facilitated by their different lifestyles: whereas SUP05 cells are streamlined, non-motile K-strategists adapted to low substrate concentrations, GD17 cells are motile r-strategists well adapted to fluctuating substrate and redox conditions. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  10. The t(14;18) translocation is absent from endothelial and follicular dendritic cells of follicular lymphoma (FL) and shows heterogeneous presence in preserved FL mantle zones.

    PubMed

    Kosmidis, Perikles; Mankel, Barbara; Fend, Falko; Adam, Patrick

    2018-05-02

    The translocation t(14;18)(q32;q21) is the genetic hallmark of follicular lymphoma (FL) and can be observed in 85-90% of cases. Whether the translocation is restricted to cells with germinal center B-cell phenotype or can be observed in other cell types of the microenvironment remains debated. Of interest, cases of associated histiocytic and dendritic cell sarcomas arising in the background of FL have been shown to be clonally related and carry the t(14;18), suggesting a "transdifferentiation" of the malignant FL clone into a neoplasm of a different hematopoietic lineage. We analyzed the presence of the t(14;18)(q32;q21) as a surrogate marker of the malignant clone in cells of the FL microenvironment using combined fluorescence immunophenotyping and interphase cytogenetics targeting the BCL2 gene locus. In addition to non-lymphoid cells in FL, we analysed FL with preserved IgD+ mantle zones and cases of in situ follicular neoplasia (ISFN) to investigate whether cells of non-germinal center B-cell phenotype are part of the malignant clone. Six (40%) of 15 manifest FL cases with preserved IgD+ mantle zones did not harbour the t(14;18)(q32;q21) translocation. In all t(14;18) + FL cases, follicular dendritic cells and endothelial cells lacked the t(14;18) translocation. 2/9 FL revealed t(14;18)- IgD+ mantle zone B-cells. In the seven ISFN cases, the t(14;18) translocation was strictly confined to germinal center cells. The t(14;18) translocation in follicular lymphoma is limited to B-cells. The origin of IgD+ mantle cells is heterogeneous, in the majority of cases belonging to the neoplastic clone, whereas a minority of cases of manifest FL show nonneoplastic mantle zones, similar to ISFN.

  11. Generation of protective T cell-independent antiviral antibody responses in SCID mice reconstituted with follicular or marginal zone B cells.

    PubMed

    Guay, Heath M; Mishra, Rabinarayan; Garcea, Robert L; Welsh, Raymond M; Szomolanyi-Tsuda, Eva

    2009-07-01

    B cells generated in the bone marrow of adult mice enter the periphery as transitional B cells and subsequently differentiate into one of two phenotypically and functionally distinct subsets, marginal zone (MZ) or follicular (Fo) B cells. Recent reports indicate, however, that in response to environmental cues, such as lymphopenia, mature Fo B cells can change to display phenotypic markers characteristic of MZ B cells. Previously, we found that splenic B cells transferred to SCID mice responded to polyoma virus (PyV) infection with T cell-independent (TI) IgM and IgG secretion, reducing the viral load and protecting mice from the lethal effect of the infection. The contribution of MZ and Fo B cell subsets to this antiviral TI-2 response, however, has not been addressed. In this study, we show that both sort-purified MZ and Fo B cells generate protective TI Ab responses to PyV infection when transferred into SCID mice. Moreover, the transferred Fo B cells in the spleens of the PyV-infected SCID mice change phenotype, with many of them displaying MZ B cell characteristics. These findings demonstrate the plasticity of the B cell subsets in virus-infected hosts and show for the first time that B cells derived exclusively from Fo B cells can effectively function in antiviral TI-2 responses.

  12. Extranodal marginal zone B cell lymphoma of the orbit in a patient with sarcoidosis: a case report.

    PubMed

    Richards, Nikisha Q; Kidwell, Earl D R; Ramadan, Ali M; Naab, Tammey J

    2014-10-20

    To describe a case of extranodal marginal zone B-cell lymphoma (EMZL) "mucosa associated lymphoid tissue (MALT)" of the orbit that presented with stage IV disease in a patient with sarcoidosis. Clinicopathologic case report. Biopsies of the lesion were performed in the operating room and the samples were submitted for pathology processing. Pathology analysis identified the lesion as an extranodal marginal zone B-cell lymphoma "mucosa associated lymphoid tissue (MALT)" via flow cytometry, histopathology, cytogenetics, and immunohistochemical staining and fluorescent in situ hybridization (FISH). The institutional review board of Howard University Hospital waived the need for IRB approval for this intraoperative finding. A 70-year-old Black woman with biopsy-proven sarcoidosis presented complaining of foreign body sensation, redness, swelling of her left upper eyelid and tearing. The patient was found to have an orbital lymphoproliferative malignancy. It is still unclear if the presence of immunosuppression or an autoimmune disease increases the risk of lymphoproliferative malignancies {6}. Malignancy should always be suspected and investigated.

  13. Virus-specific antibodies allow viral replication in the marginal zone, thereby promoting CD8+ T-cell priming and viral control

    PubMed Central

    Duhan, Vikas; Khairnar, Vishal; Friedrich, Sarah-Kim; Zhou, Fan; Gassa, Asmae; Honke, Nadine; Shaabani, Namir; Gailus, Nicole; Botezatu, Lacramioara; Khandanpour, Cyrus; Dittmer, Ulf; Häussinger, Dieter; Recher, Mike; Hardt, Cornelia; Lang, Philipp A.; Lang, Karl S.

    2016-01-01

    Clinically used human vaccination aims to induce specific antibodies that can guarantee long-term protection against a pathogen. The reasons that other immune components often fail to induce protective immunity are still debated. Recently we found that enforced viral replication in secondary lymphoid organs is essential for immune activation. In this study we used the lymphocytic choriomeningitis virus (LCMV) to determine whether enforced virus replication occurs in the presence of virus-specific antibodies or virus-specific CD8+ T cells. We found that after systemic recall infection with LCMV-WE the presence of virus-specific antibodies allowed intracellular replication of virus in the marginal zone of spleen. In contrast, specific antibodies limited viral replication in liver, lung, and kidney. Upon recall infection with the persistent virus strain LCMV-Docile, viral replication in spleen was essential for the priming of CD8+ T cells and for viral control. In contrast to specific antibodies, memory CD8+ T cells inhibited viral replication in marginal zone but failed to protect mice from persistent viral infection. We conclude that virus-specific antibodies limit viral infection in peripheral organs but still allow replication of LCMV in the marginal zone, a mechanism that allows immune boosting during recall infection and thereby guarantees control of persistent virus. PMID:26805453

  14. Inhalation exposure to cleaning products: application of a two-zone model.

    PubMed

    Earnest, C Matt; Corsi, Richard L

    2013-01-01

    In this study, modifications were made to previously applied two-zone models to address important factors that can affect exposures during cleaning tasks. Specifically, we expand on previous applications of the two-zone model by (1) introducing the source in discrete elements (source-cells) as opposed to a complete instantaneous release, (2) placing source cells in both the inner (near person) and outer zones concurrently, (3) treating each source cell as an independent mixture of multiple constituents, and (4) tracking the time-varying liquid concentration and emission rate of each constituent in each source cell. Three experiments were performed in an environmentally controlled chamber with a thermal mannequin and a simplified pure chemical source to simulate emissions from a cleaning product. Gas phase concentration measurements were taken in the bulk air and in the breathing zone of the mannequin to evaluate the model. The mean ratio of the integrated concentration in the mannequin's breathing zone to the concentration in the outer zone was 4.3 (standard deviation, σ = 1.6). The mean ratio of measured concentration in the breathing zone to predicted concentrations in the inner zone was 0.81 (σ = 0.16). Intake fractions ranged from 1.9 × 10(-3) to 2.7 × 10(-3). Model results reasonably predict those of previous exposure monitoring studies and indicate the inadequacy of well-mixed single-zone model applications for some but not all cleaning events.

  15. Proliferation zones in the axolotl brain and regeneration of the telencephalon

    PubMed Central

    2013-01-01

    Background Although the brains of lower vertebrates are known to exhibit somewhat limited regeneration after incisional or stab wounds, the Urodele brain exhibits extensive regeneration after massive tissue removal. Discovering whether and how neural progenitor cells that reside in the ventricular zones of Urodeles proliferate to mediate tissue repair in response to injury may produce novel leads for regenerative strategies. Here we show that endogenous neural progenitor cells resident to the ventricular zone of Urodeles spontaneously proliferate, producing progeny that migrate throughout the telencephalon before terminally differentiating into neurons. These progenitor cells appear to be responsible for telencephalon regeneration after tissue removal and their activity may be up-regulated by injury through an olfactory cue. Results There is extensive proliferation of endogenous neural progenitor cells throughout the ventricular zone of the adult axolotl brain. The highest levels are observed in the telencephalon, especially the dorsolateral aspect, and cerebellum. Lower levels are observed in the mesencephalon and rhombencephalon. New cells produced in the ventricular zone migrate laterally, dorsally and ventrally into the surrounding neuronal layer. After migrating from the ventricular zone, the new cells primarily express markers of neuronal differentiative fates. Large-scale telencephalic tissue removal stimulates progenitor cell proliferation in the ventricular zone of the damaged region, followed by proliferation in the tissue that surrounds the healing edges of the wound until the telencephalon has completed regeneration. The proliferative stimulus appears to reside in the olfactory system, because telencephalic regeneration does not occur in the brains of olfactory bulbectomized animals in which the damaged neural tissue simply heals over. Conclusion There is a continual generation of neuronal cells from neural progenitor cells located within the

  16. The Aurora-B-dependent NoCut checkpoint prevents damage of anaphase bridges after DNA replication stress.

    PubMed

    Amaral, Nuno; Vendrell, Alexandre; Funaya, Charlotta; Idrissi, Fatima-Zahra; Maier, Michael; Kumar, Arun; Neurohr, Gabriel; Colomina, Neus; Torres-Rosell, Jordi; Geli, María-Isabel; Mendoza, Manuel

    2016-05-01

    Anaphase chromatin bridges can lead to chromosome breakage if not properly resolved before completion of cytokinesis. The NoCut checkpoint, which depends on Aurora B at the spindle midzone, delays abscission in response to chromosome segregation defects in yeast and animal cells. How chromatin bridges are detected, and whether abscission inhibition prevents their damage, remain key unresolved questions. We find that bridges induced by DNA replication stress and by condensation or decatenation defects, but not dicentric chromosomes, delay abscission in a NoCut-dependent manner. Decatenation and condensation defects lead to spindle stabilization during cytokinesis, allowing bridge detection by Aurora B. NoCut does not prevent DNA damage following condensin or topoisomerase II inactivation; however, it protects anaphase bridges and promotes cellular viability after replication stress. Therefore, the molecular origin of chromatin bridges is critical for activation of NoCut, which plays a key role in the maintenance of genome stability after replicative stress.

  17. Measuring Spatial Variability of Vapor Flux to Characterize Vadose-zone VOC Sources: Flow-cell Experiments

    DOE PAGES

    Mainhagu, Jon; Morrison, C.; Truex, Michael J.; ...

    2014-08-05

    A method termed vapor-phase tomography has recently been proposed to characterize the distribution of volatile organic contaminant mass in vadose-zone source areas, and to measure associated three-dimensional distributions of local contaminant mass discharge. The method is based on measuring the spatial variability of vapor flux, and thus inherent to its effectiveness is the premise that the magnitudes and temporal variability of vapor concentrations measured at different monitoring points within the interrogated area will be a function of the geospatial positions of the points relative to the source location. A series of flow-cell experiments was conducted to evaluate this premise. Amore » well-defined source zone was created by injection and extraction of a non-reactive gas (SF6). Spatial and temporal concentration distributions obtained from the tests were compared to simulations produced with a mathematical model describing advective and diffusive transport. Tests were conducted to characterize both areal and vertical components of the application. Decreases in concentration over time were observed for monitoring points located on the opposite side of the source zone from the local–extraction point, whereas increases were observed for monitoring points located between the local–extraction point and the source zone. We found that the results illustrate that comparison of temporal concentration profiles obtained at various monitoring points gives a general indication of the source location with respect to the extraction and monitoring points.« less

  18. Morphologic and Functional Effects of Gamma Secretase Inhibition on Splenic Marginal Zone B Cells

    PubMed Central

    de Vera Mudry, Maria Cristina; Regenass-Lechner, Franziska; Ozmen, Laurence; Altmann, Bernd; Festag, Matthias; Singer, Thomas; Müller, Lutz; Jacobsen, Helmut; Flohr, Alexander

    2012-01-01

    The γ-secretase complex is a promising target in Alzheimer's disease because of its role in the amyloidogenic processing of β-amyloid precursor protein. This enzyme also catalyzes the cleavage of Notch receptor, resulting in the nuclear translocation of intracellular Notch where it modulates gene transcription. Notch signaling is essential in cell fate decisions during embryogenesis, neuronal differentiation, hematopoiesis, and development of T and B cells, including splenic marginal zone (MZ) B cells. This B cell compartment participates in the early phases of the immune response to blood-borne bacteria and viruses. Chronic treatment with the oral γ-secretase inhibitor RO4929097 resulted in dose-dependent decreased cellularity (atrophy) of the MZ of rats and mice. Significant decreases in relative MZ B-cell numbers of RO4929097-treated animals were confirmed by flow cytometry. Numbers of MZ B cells reverted to normal after a sufficient RO4929097-free recovery period. Functional characterization of the immune response in relation to RO4929097-related MZ B cell decrease was assessed in mice vaccinated with inactivated vesicular stomatitis virus (VSV). Compared with the immunosuppressant cyclosporin A, RO4929097 caused only mild and reversible delayed early neutralizing IgM and IgG responses to VSV. Thus, the functional consequence of MZ B cell decrease on host defense is comparatively mild. PMID:23316412

  19. TfVPS32 Regulates Cell Division in the Parasite Tritrichomonas foetus.

    PubMed

    Iriarte, Lucrecia S; Midlej, Victor; Frontera, Lorena S; Moros Duarte, Daniel; Barbeito, Claudio G; de Souza, Wanderley; Benchimol, Marlene; de Miguel, Natalia; Coceres, Veronica M

    2018-01-01

    The flagellated protist Tritrichomonas foetus is a parasite that causes bovine trichomonosis, a major sexually transmitted disease in cattle. Cell division has been described as a key player in controlling cell survival in other cells, including parasites but there is no information on the regulation of this process in T. foetus. The regulation of cytokinetic abscission, the final stage of cell division, is mediated by members of the ESCRT (endosomal sorting complex required for transport) machinery. VPS32 is a subunit within the ESCRTIII complex and here, we report that TfVPS32 is localized on cytoplasmic vesicles and a redistribution of the protein to the midbody is observed during the cellular division. In concordance with its localization, deletion of TfVPS32 C-terminal alpha helices (α5 helix and/or α4-5 helix) leads to abnormal T. foetus growth, an increase in the percentage of multinucleated parasites and cell cycle arrest at G2/M phase. Together, these results indicate a role of this protein in controlling normal cell division. © 2017 The Author(s) Journal of Eukaryotic Microbiology © 2017 International Society of Protistologists.

  20. [Radiation exposure of cultured tissue cells and animals (mice) within 10-kilometers zone of accident at Chernobyl nuclear plant. Effect on radiosensitivity to future radiation].

    PubMed

    Pelevina, I I; Afanasév, G G; Gotlib, V Ia; Alferovich, A A; Antoshchina, M M; Riabchenko, N I; Saenko, A S; Riabtsev, I A; Riabov, I N

    1993-01-01

    The effect of chronic low-level radiation exposure on radiosensitivity to posterior acute irradiation at high doses has been studied. Cells and mice were exposed within the ten-kilometer zone of Chernobyl disaster during various spaces of time (1-12 days), then over one or more days were additionally irradiated by doses of 1-4 Gy. It was shown that no adaptive response was developed under chronic exposure of cells and mice within the zone of disaster. On the contrary increased sensitivity to posterior irradiation was revealed. The number of cytogenetic damages of cultured tissue cells and marrow cells (chromosome aberrations and micronuclei) increases, the spectrum of aberrations being shifted to chromosome type, cells with multiaberration appearing. The decay of chromatine increases indicating an interphase death; the number of leucocytes in peripheral blood decreases.

  1. The migrational patterns and developmental fates of glial precursors in the rat subventricular zone are temporally regulated.

    PubMed

    Levison, S W; Chuang, C; Abramson, B J; Goldman, J E

    1993-11-01

    Postnatal gliogenesis in the rodent forebrain was studied by infecting subventricular zone cells of either neonates or juvenile rats with replication-deficient retroviruses that encode reporter enzymes, enabling the migration and fate of these germinal zone cells to be traced over the ensuing several weeks. Neither neonatal nor juvenile subventricular zone cells migrated substantially along the rostral-caudal axis. Neonatal subventricular zone cells migrated dorsally and laterally into hemispheric gray and white matter and became both astrocytes and oligodendrocytes. Juvenile subventricular zone cells migrated into more medial areas of the subcortical white matter and on occasion appeared in the white matter of the contralateral hemisphere, but rarely migrated into the neocortex. Juvenile subventricular zone cells almost exclusively differentiated into oligodendrocytes. Thus, the migratory patterns and the developmental fates of subventricular zone cells change during the first 2 weeks of life. When either neonatal or juvenile subventricular zone cells were labeled in vivo and then removed and cultured, some generated homogeneous clones that contained either astrocytes with a 'type 1' phenotype or oligodendrocytes, but some generated heterogeneous clones that contained both glial types. These results provide additional evidence for a common progenitor for astrocytes and oligodendrocytes and strongly suggest that temporally and spatially regulated environmental signals control the destiny of glial progenitors during postnatal development.

  2. Inhibition of glycogen synthase kinase 3 increased subventricular zone stem cells proliferation.

    PubMed

    Pachenari, Narges; Kiani, Sahar; Javan, Mohammad

    2017-09-01

    The effects of Wnt signaling modifiers on cell proliferation, seem to be cell specific. Enhancing the proliferation of subventricular zone (SVZ) progenitors has been in the focus of research in recent years. Here we investigate the effect of CHIR99021, a Glycogen Synthase Kinase 3 (GSk-3) inhibitor, on SVZ progenitor's proliferation both in vivo and in vitro. Neural stem cells were extracted from the adult C57bl/6 by mincing and trypsin treatment followed by culturing in specific medium. Sphere cells formed within about 7-10days and were characterized by immunostaining. Number of spheres and their size was assessed following exposure to different concentration of CHIR99021 or vehicle. For in vivo studies, animals received intracerebroventricular (i.c.v.) injection of CHIR99021 or vehicle for four days. A subgroup of animals, after 4days treatment with CHIR99021 received intranasal kainic acid to induce local neurodegeneration in CA3 area of hippocampus. Inhibition of GSk-3 by CHIR99021 increased neural progenitor proliferation and the effect of CHIR99021 was long lasting so that the treated cells showed higher proliferation even after CHIR99021 removal. In vivo administration of CHIR99021 increased the number of neural progenitors at the rims of lateral ventricles especially when the treatment was followed by kainic acid administration which induces neural insult. Results showed that direct administration of CHIR99021 into the culture medium or animal brain increased the number of SVZ progenitors, especially when a neural insult was induced in the hippocampus. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  3. Soft x-ray microscope with zone plates at UVSOR

    NASA Astrophysics Data System (ADS)

    Watanabe, Norio; Shimanuki, Yoshio; Taniguchi, Mieko; Kihara, Hiroshi

    1993-01-01

    A soft x-ray microscope with zone plates was set up at UVSOR (Okazaki, Japan). A 0.41 micrometers line and space pattern was clearly distinguished using an objective zone plate with the outermost zone width of 0.41 micrometers . Modulation transfer functions were measured at wavelengths of 3.1 nm and 5.4 nm, and compared with theoretical calculations. Considering the resolution of a microchannel plate used as a detector, the agreement is fairly good. With this microscope, some biological specimens such as diatoms, spicule of trepang, crab and rabbit muscles, human blood cells, human chromosomes, and magnetotactic bacterium were observed at 3.1 nm and 5.4 nm. With an environmental chamber (wet cell) using polypropylene foils as windows, wet specimens were observed at a wavelength of 4.6 nm. Images of spicule of trepang, human blood cell, and cultured protoplast of plant cell stained by methyl mercury were observed with good contrast.

  4. Molecular pathogenesis of splenic and nodal marginal zone lymphoma.

    PubMed

    Spina, Valeria; Rossi, Davide

    Genomic studies have improved our understanding of the biological basis of splenic (SMZL) and nodal (NMZL) marginal zone lymphoma by providing a comprehensive and unbiased view of the genes/pathways that are deregulated in these diseases. Consistent with the physiological involvement of NOTCH, NF-κB, B-cell receptor and toll-like receptor signaling in mature B-cells differentiation into the marginal zone B-cells, many oncogenic mutations of genes involved in these pathways have been identified in SMZL and NMZL. Beside genetic lesions, also epigenetic and post-transcriptional modifications contribute to the deregulation of marginal zone B-cell differentiation pathways in SMZL and NMZL. This review describes the progress in understanding the molecular mechanism underlying SMZL and NMZL, including molecular and post-transcriptional modifications, and discusses how information gained from these efforts has provided new insights on potential targets of diagnostic, prognostic and therapeutic relevance in SMZL and NMZL. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Stochastic Ground Water Flow Simulation with a Fracture Zone Continuum Model

    USGS Publications Warehouse

    Langevin, C.D.

    2003-01-01

    A method is presented for incorporating the hydraulic effects of vertical fracture zones into two-dimensional cell-based continuum models of ground water flow and particle tracking. High hydraulic conductivity features are used in the model to represent fracture zones. For fracture zones that are not coincident with model rows or columns, an adjustment is required for the hydraulic conductivity value entered into the model cells to compensate for the longer flowpath through the model grid. A similar adjustment is also required for simulated travel times through model cells. A travel time error of less than 8% can occur for particles moving through fractures with certain orientations. The fracture zone continuum model uses stochastically generated fracture zone networks and Monte Carlo analysis to quantify uncertainties with simulated advective travel times. An approach is also presented for converting an equivalent continuum model into a fracture zone continuum model by establishing the contribution of matrix block transmissivity to the bulk transmissivity of the aquifer. The methods are used for a case study in west-central Florida to quantify advective travel times from a potential wetland rehydration site to a municipal supply wellfield. Uncertainties in advective travel times are assumed to result from the presence of vertical fracture zones, commonly observed on aerial photographs as photolineaments.

  6. Long-term outcome for patients with early stage marginal zone lymphoma and mantle cell lymphoma.

    PubMed

    Barzenje, Dlawer Abdulla; Holte, Harald; Fosså, Alexander; Ghanima, Waleed; Liestøl, Knut; Delabie, Jan; Kolstad, Arne

    2017-03-01

    In this study with prolonged follow up, we compared clinical outcome, including cause of death and incidence of second cancer, for patients with early stage extranodal marginal zone lymphoma (EMZL, 49 patients), nodal marginal zone lymphoma (NMZL, nine patients) and mantle cell lymphoma (MCL, 42 patients) with emphasis on potential benefit of radiotherapy. Radiotherapy was given to 40 patients with EMZL (nine had surgery only) and all NMZL patients. MCL patients received radiotherapy (17 patients), chemotherapy followed by radiotherapy (13 patients) or chemotherapy alone (12 patients). Compared to a matched control population no increased risk of second cancer or cardiovascular disease was observed. Radiotherapy alone was effective in EMZL and NMZL with low-relapse rates (20% and 33%) and a 10-year overall survival of 78% and 56%, respectively. High-relapse rate and inferior OS in MCL underline the need for extended staging with endoscopy and PET/CT and possibly for novel strategies.

  7. Toll-like receptor expression and function differ between splenic marginal zone B cell lymphoma and splenic diffuse red pulp B cell lymphoma

    PubMed Central

    Verney, Aurélie; Traverse-Glehen, Alexandra; Callet-Bauchu, Evelyne; Jallades, Laurent; Magaud, Jean-Pierre; Salles, Gilles; Genestier, Laurent; Baseggio, Lucile

    2018-01-01

    In splenic marginal zone lymphoma (SMZL), specific and functional Toll-like Receptor (TLR) patterns have been recently described, suggesting their involvement in tumoral proliferation. Splenic diffuse red pulp lymphoma with villous lymphocytes (SDRPL) is close to but distinct from SMZL, justifying here the comparison of TLR patterns and functionality in both entities. Distinct TLR profiles were observed in both lymphoma subtypes. SDRPL B cells showed higher expression of TLR7 and to a lesser degree TLR9, in comparison to SMZL B cells. In both entities, TLR7 and TLR9 pathways appeared functional, as shown by IL-6 production upon TLR7 and TLR9 agonists stimulations. Interestingly, circulating SDRPL, but not SMZL B cells, constitutively expressed CD86. In addition, stimulation with both TLR7 and TLR9 agonists significantly increased CD80 expression in circulating SDRPL but not SMZL B cells. Finally, TLR7 and TLR9 stimulations had no impact on proliferation and apoptosis of SMZL or SDRPL B cells. In conclusion, SMZL and SDRPL may derive from different splenic memory B cells with specific immunological features that can be used as diagnosis markers in the peripheral blood.

  8. Partitioning of photosynthate within and distal to the growth zone of tall fescue leaf blades

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

    Allard, G.; Nelson, C.J.

    The growth zone of developing tall fescue leaf blades, consisting of zones of cell division, cell elongation and cell maturation, are a strong sink for photosynthate. Distribution of {sup 14}C along the growth zone and partitioning between water-soluble carbohydrates (WSC) and WSC-free dry matter (SDM) were observed for up to 64 h after labelling the youngest fully expanded leaf or the exposed tip of the elongating leaf with {sup 14}CO{sub 2}. Deposition rates of {sup 14}C were estimated using the continuity equation. The cell elongation zone, especially the WSC fraction, was the strongest sink for {sup 14}C. In the proximalmore » end of the maturation zone, partitioning of {sup 14}C shifted from being allocated mainly to the WSC fraction after 2 h to an equal distribution between WSC and SDM at the distal end of the zone after 64 h. A significant proportion of {sup 14}C in the SDM fraction of the maturation zone could be attributed to redistribution from WSC.« less

  9. Photosynthate partitioning in basal zones of tall fescue leaf blades. [Festuca arundinacea Schreb

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

    Allard, G.; Nelson, C.J.

    Elongating grass leaves have successive zones of cell division, cell elongation, and cell maturation in the basal portion of the blade and are a strong sink for photosynthate. Our objective was to determine dry matter (DM) deposition and partitioning in basal zones of elongating tall fescue (Festuca arundinacea Schreb.) leaf blades. Vegetative tall fescue plants were grown in continuous light (350 micromoles per square meter per second photosynthetic photon flux density) to obtain a constant spatial distribution of elongation growth with time. Content and net deposition rates of water-soluble carbohydrates (WSC) and DM along elongating leaf blades were determined. Thesemore » data were compared with accumulation of {sup 14}C in the basal zones following leaf-labeling with {sup 14}CO{sub 2}. Net deposition of DM was highest in the active cell elongation zone, due mainly to deposition of WSC. The maturation zone, just distal to the elongation zone, accounted for 22% of total net deposition of DM in elongating leaves. However, the spatial profile of {sup 14}C accumulation suggested that the elongation zone and the maturation zone were sinks of equal strength. WSC-free DM accounted for 55% of the total net DM deposition in elongating leaf blades, but only 10% of incoming {sup 14}C-photosynthate accumulated in the water-insoluble fraction (WIF {approximately} WSC-free DM) after 2 hours. In the maturation zone, more WSC was used for synthesis of WSC-free DM than was imported as recent photosynthate.« less

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

    PubMed Central

    Olivera-Pasilio, Valentina; Peterson, Daniel A.; Castelló, María E.

    2014-01-01

    Proliferation of stem/progenitor cells during development provides for the generation of mature cell types in the CNS. While adult brain proliferation is highly restricted in the mammals, it is widespread in teleosts. The extent of adult neural proliferation in the weakly electric fish, Gymnotus omarorum has not yet been described. To address this, we used double thymidine analog pulse-chase labeling of proliferating cells to identify brain proliferation zones, characterize their cellular composition, and analyze the fate of newborn cells in adult G. omarorum. Short thymidine analog chase periods revealed the ubiquitous distribution of adult brain proliferation, similar to other teleosts, particularly Apteronotus leptorhynchus. Proliferating cells were abundant at the ventricular-subventricular lining of the ventricular-cisternal system, adjacent to the telencephalic subpallium, the diencephalic preoptic region and hypothalamus, and the mesencephalic tectum opticum and torus semicircularis. Extraventricular proliferation zones, located distant from the ventricular-cisternal system surface, were found in all divisions of the rombencephalic cerebellum. We also report a new adult proliferation zone at the caudal-lateral border of the electrosensory lateral line lobe. All proliferation zones showed a heterogeneous cellular composition. The use of short (24 h) and long (30 day) chase periods revealed abundant fast cycling cells (potentially intermediate amplifiers), sparse slow cycling (potentially stem) cells, cells that appear to have entered a quiescent state, and cells that might correspond to migrating newborn neural cells. Their abundance and migration distance differed among proliferation zones: greater numbers and longer range and/or pace of migrating cells were associated with subpallial and cerebellar proliferation zones. PMID:25249943

  11. Splenic marginal zone lymphoma: comprehensive analysis of gene expression and miRNA profiling.

    PubMed

    Arribas, Alberto J; Gómez-Abad, Cristina; Sánchez-Beato, Margarita; Martinez, Nerea; Dilisio, Lorena; Casado, Felipe; Cruz, Miguel A; Algara, Patrocinio; Piris, Miguel A; Mollejo, Manuela

    2013-07-01

    Splenic marginal zone lymphoma is a small B-cell neoplasm whose molecular pathogenesis is still essentially unknown and whose differentiation from other small B-cell lymphomas is hampered by the lack of specific markers. We have analyzed the gene expression and miRNA profiles of 31 splenic marginal zone lymphoma cases. For comparison, 7 spleens with reactive lymphoid hyperplasia, 10 spleens infiltrated by chronic lymphocytic leukemia, 12 spleens with follicular lymphoma, 6 spleens infiltrated by mantle cell lymphoma and 15 lymph nodes infiltrated by nodal marginal zone lymphoma were included. The results were validated by qRT-PCR in an independent series including 77 paraffin-embedded splenic marginal zone lymphomas. The splenic marginal zone lymphoma miRNA signature had deregulated expression of 51 miRNAs. The most highly overexpressed miRNAs were miR-155, miR-21, miR-34a, miR-193b and miR-100, while the most repressed miRNAs were miR-377, miR-27b, miR-145, miR-376a and miR-424. MiRNAs located in 14q32-31 were underexpressed in splenic marginal zone lymphoma compared with reactive lymphoid tissues and other B-cell lymphomas. Finally, the gene expression data were integrated with the miRNA profile to identify functional relationships between genes and deregulated miRNAs. Our study reveals miRNAs that are deregulated in splenic marginal zone lymphoma and identifies new candidate diagnostic molecules for splenic marginal zone lymphoma.

  12. Spred1, a negative regulator of Ras–MAPK–ERK, is enriched in CNS germinal zones, dampens NSC proliferation, and maintains ventricular zone structure

    PubMed Central

    Phoenix, Timothy N.; Temple, Sally

    2010-01-01

    Neural stem cells (NSCs) have great potential for self-renewal, which must be tightly regulated to generate appropriate cell numbers during development and to prevent tumor formation. The Ras–MAPK–ERK pathway affects mitogen-stimulated proliferation, and negative regulators are likely to be important for keeping self-renewal in check. Sprouty-related protein with an EVH1 domain (Spred1) is a recently discovered negative Ras–MAPK–ERK regulator linked to a neurofibromatosis 1 (NF-1)-like human syndrome; however, its role in CNS development has not been explored. We show that Spred1 is highly enriched in CNS germinal zones during neurogenesis. Spred1 knockdown increases NSC self-renewal and progenitor proliferation cell-autonomously, and overexpression causes premature differentiation. Surprisingly, Spred1 knockdown in vivo in the embryonic mouse forebrain frequently resulted in periventricular heterotopia, developmental abnormalities often associated with mutations in genes in the vesicular trafficking pathway that cause disruption of germinal zones and impair cell migration. In cortical progenitor cells, Spred1 localizes within distinct vesicles, indicating a potential role in transport. Spred1 knockdown gradually leads to disruption of the apical ventricular zone and loss of radial glia alignment. This impairs late neuronal migration, resulting in the formation of periventricular masses. Thus, Spred1 is critical for normal cortical development, as it modulates progenitor self-renewal/proliferation and helps maintain the integrity and organization of germinal zones. PMID:20047999

  13. Evidence of a Cell Surface Role for Hsp90 Complex Proteins Mediating Neuroblast Migration in the Subventricular Zone.

    PubMed

    Miyakoshi, Leo M; Marques-Coelho, Diego; De Souza, Luiz E R; Lima, Flavia R S; Martins, Vilma R; Zanata, Silvio M; Hedin-Pereira, Cecilia

    2017-01-01

    In most mammalian brains, the subventricular zone (SVZ) is a germinative layer that maintains neurogenic activity throughout adulthood. Neuronal precursors arising from this region migrate through the rostral migratory stream (RMS) and reach the olfactory bulbs where they differentiate and integrate into the local circuitry. Recently, studies have shown that heat shock proteins have an important role in cancer cell migration and blocking Hsp90 function was shown to hinder cell migration in the developing cerebellum. In this work, we hypothesize that chaperone complexes may have an important function regulating migration of neuronal precursors from the subventricular zone. Proteins from the Hsp90 complex are present in the postnatal SVZ as well as in the RMS. Using an in vitro SVZ explant model, we have demonstrated the expression of Hsp90 and Hop/STI1 by migrating neuroblasts. Treatment with antibodies against Hsp90 and co-chaperone Hop/STI1, as well as Hsp90 and Hsp70 inhibitors hinder neuroblast chain migration. Time-lapse videomicroscopy analysis revealed that cell motility and average migratory speed was decreased after exposure to both antibodies and inhibitors. Antibodies recognizing Hsp90, Hsp70, and Hop/STI1 were found bound to the membranes of cells from primary SVZ cultures and biotinylation assays demonstrated that Hsp70 and Hop/STI1 could be found on the external leaflet of neuroblast membranes. The latter could also be detected in conditioned medium samples obtained from cultivated SVZ cells. Our results suggest that chaperones Hsp90, Hsp70, and co-chaperone Hop/STI1, components of the Hsp90 complex, regulate SVZ neuroblast migration in a concerted manner through an extracellular mechanism.

  14. The transcriptional coactivator Maml1 is required for Notch2-mediated marginal zone B-cell development

    PubMed Central

    Maillard, Ivan; Nakamura, Makoto; Pear, Warren S.; Griffin, James D.

    2007-01-01

    Signaling mediated by various Notch receptors and their ligands regulates diverse biological processes, including lymphoid cell fate decisions. Notch1 is required during T-cell development, while Notch2 and the Notch ligand Delta-like1 control marginal zone B (MZB) cell development. We previously determined that Mastermind-like (MAML) transcriptional coactivators are required for Notchinduced transcription by forming ternary nuclear complexes with Notch and the transcription factor CSL. The 3 MAML family members (MAML1-MAML3) are collectively essential for Notch activity in vivo, but whether individual MAMLs contribute to the specificity of Notch functions is unknown. Here, we addressed this question by studying lymphopoiesis in the absence of the Maml1 gene. Since Maml1−/− mice suffered perinatal lethality, hematopoietic chimeras were generated with Maml1−/−, Maml1+/−, or wild-type fetal liver progenitors. Maml1 deficiency minimally affected T-cell development, but was required for the development of MZB cells, similar to the phenotype of Notch2 deficiency. Moreover, the number of MZB cells correlated with Maml1 gene dosage. Since all 3 Maml genes were expressed in MZB cells and their precursors, these results suggest that Maml1 is specifically required for Notch2 signaling in MZB cells. PMID:17699740

  15. Methylation patterns in marginal zone lymphoma.

    PubMed

    Arribas, Alberto J; Bertoni, Francesco

    Promoter DNA methylation is a major regulator of gene expression and transcription. The identification of methylation changes is important for understanding disease pathogenesis, for identifying prognostic markers and can drive novel therapeutic approaches. In this review we summarize the current knowledge regarding DNA methylation in MALT lymphoma, splenic marginal zone lymphoma, nodal marginal zone lymphoma. Despite important differences in the study design for different publications and the existence of a sole large and genome-wide methylation study for splenic marginal zone lymphoma, it is clear that DNA methylation plays an important role in marginal zone lymphomas, in which it contributes to the inactivation of tumor suppressors but also to the expression of genes sustaining tumor cell survival and proliferation. Existing preclinical data provide the rationale to target the methylation machinery in these disorders. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Natural History Study of Monoclonal B Cell Lymphocytosis (MBL), Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma (CLL/SLL), Lymphoplasmacytic Lymphoma (LPL)/Waldenstrom Macroglobulinemia (WM), and Splenic Marginal Zone Lymphoma (SMZL)

    ClinicalTrials.gov

    2018-06-27

    B-Cell Chronic Lymphocytic Leukemia; Monoclonal B-Cell Lymphocytosis; Lymhoma, Small Lymphocytic; Chronic Lymphocytic Leukemia; Lymphoplasmacytic Lymphoma; Waldenstrom Macroglobulinemia; Splenic Marginal Zone Lymphoma

  17. Increased Re-Entry into Cell Cycle Mitigates Age-Related Neurogenic Decline in the Murine Subventricular Zone

    PubMed Central

    Stoll, Elizabeth A.; Habibi, Behnum A.; Mikheev, Andrei M.; Lasiene, Jurate; Massey, Susan C.; Swanson, Kristin R.; Rostomily, Robert C.; Horner, Philip J.

    2012-01-01

    Although new neurons are produced in the subventricular zone (SVZ) of the adult mammalian brain, fewer functional neurons are produced with increasing age. The age-related decline in neurogenesis has been attributed to a decreased pool of neural progenitor cells (NPCs), an increased rate of cell death, and an inability to undergo neuronal differentiation and develop functional synapses. The time between mitotic events has also been hypothesized to increase with age, but this has not been directly investigated. Studying primary-cultured NPCs from the young adult and aged mouse forebrain, we observe that fewer aged cells are dividing at a given time; however, the mitotic cells in aged cultures divide more frequently than mitotic cells in young cultures during a 48-hour period of live-cell time-lapse imaging. Double-thymidine-analog labeling also demonstrates that fewer aged cells are dividing at a given time, but those that do divide are significantly more likely to re-enter the cell cycle within a day, both in vitro and in vivo. Meanwhile, we observed that cellular survival is impaired in aged cultures. Using our live-cell imaging data, we developed a mathematical model describing cell cycle kinetics to predict the growth curves of cells over time in vitro and the labeling index over time in vivo. Together, these data surprisingly suggest that progenitor cells remaining in the aged SVZ are highly proliferative. PMID:21948688

  18. Bromine cycle in subduction zones through in situ Br monitoring in diamond anvil cells

    NASA Astrophysics Data System (ADS)

    Bureau, Hélène; Foy, Eddy; Raepsaet, Caroline; Somogyi, Andrea; Munsch, Pascal; Simon, Guilhem; Kubsky, Stefan

    2010-07-01

    The geochemical partitioning of bromine between hydrous haplogranitic melts, initially enriched with respect to Br and aqueous fluids, has been continuously monitored in situ during decompression. Experiments were carried out in diamond anvil cells from 890 °C to room temperature and from 1.7 GPa to room pressure, typically from high P, T conditions corresponding to total miscibility (presence of a supercritical fluid). Br contents were measured in aqueous fluids, hydrous melts and supercritical fluids. Partition coefficients of bromine were characterized at pressure and temperature between fluids, hydrous melts and/or glasses, as appropriate: DBrfluid/melt = (Br) fluid/(Br) melt, ranges from 2.18 to 9.2 ± 0.5 for conditions within the ranges 0.66-1.7 GPa, 590-890 °C; and DBrfluid/glass = (Br) fluid/(Br) glass ranges from 60 to 375 at room conditions. The results suggest that because high pressure melts and fluids are capable of accepting high concentrations of bromine, this element may be efficiently removed from the slab to the mantle source of arc magmas. We show that Br may be highly concentrated in subduction zone magmas and strongly enriched in subduction-related volcanic gases, because its mobility is strongly correlated with that of water during magma degassing. Furthermore, our experimental results suggest that a non negligible part of Br present in the subducted slab may remain in the down-going slab, being transported toward the transition zone. This indicates that the Br cycle in subduction zones is in fact divided in two related but independent parts: (1) a shallower one where recycled Br may leave the slab with a water and silica-bearing "fluid" leading to enriched arc magmas that return Br to the atmosphere. (2) A deeper cycle where Br may be recycled back to the mantle maybe to the transition zone, where it may be present in high pressure water-rich metasomatic fluids.

  19. NF-κB deregulation in splenic marginal zone lymphoma.

    PubMed

    Spina, Valeria; Rossi, Davide

    2016-08-01

    Splenic marginal zone lymphoma is a rare mature B-cell malignancy involving the spleen, bone marrow and blood. Over the past years, the rapid expansion of sequencing technologies allowing the genome-wide assessment of genomic, epigenetic and transcriptional changes has revolutionized our understanding of the biological basis of splenic marginal zone lymphoma by providing a comprehensive and unbiased view of the genes/pathways that are deregulated in this disease. NF-κB is a family of transcription factors that plays critical roles in development, survival, and activation of B lymphocytes. Consistent with the physiological involvement of NF-κB signalling in proliferation and commitment of mature B-cells to the marginal zone of the spleen, many oncogenic mutations involved in constitutive activation of the NF-κB pathway were recently identified in splenic marginal zone lymphoma. This review describes the progress in understanding the mechanism of NF-κB activation in splenic marginal zone lymphoma, including molecular, epigenetic and post-transcriptional modifications of NF-κB genes and of upstream pathways, and discusses how information gained from these efforts has provided new insights on potential targets of diagnostic, prognostic and therapeutic relevance for splenic marginal zone lymphoma. Copyright © 2016. Published by Elsevier Ltd.

  20. Ionizing Radiation Perturbs Cell Cycle Progression of Neural Precursors in the Subventricular Zone Without Affecting Their Long-Term Self-Renewal

    PubMed Central

    Chen, Hongxin; Goodus, Matthew T; de Toledo, Sonia M; Azzam, Edouard I; Levison, Steven W

    2015-01-01

    Damage to normal human brain cells from exposure to ionizing radiation may occur during the course of radiotherapy or from accidental exposure. Delayed effects may complicate the immediate effects resulting in neurodegeneration and cognitive decline. We examined cellular and molecular changes associated with exposure of neural stem/progenitor cells (NSPs) to 137Cs γ-ray doses in the range of 0 to 8 Gy. Subventricular zone NSPs isolated from newborn mouse pups were analyzed for proliferation, self-renewal, and differentiation, shortly after irradiation. Strikingly, there was no apparent increase in the fraction of dying cells after irradiation, and the number of single cells that formed neurospheres showed no significant change from control. Upon differentiation, irradiated neural precursors did not differ in their ability to generate neurons, astrocytes, and oligodendrocytes. By contrast, progression of NSPs through the cell cycle decreased dramatically after exposure to 8 Gy (p < .001). Mice at postnatal day 10 were exposed to 8 Gy of γ rays delivered to the whole body and NSPs of the subventricular zone were analyzed using a four-color flow cytometry panel combined with ethynyl deoxyuridine incorporation. Similar flow cytometric analyses were performed on NSPs cultured as neurospheres. These studies revealed that neither the percentage of neural stem cells nor their proliferation was affected. By contrast, γ-irradiation decreased the proliferation of two classes of multipotent cells and increased the proliferation of a specific glial-restricted precursor. Altogether, these results support the conclusion that primitive neural precursors are radioresistant, but their proliferation is slowed down as a consequence of γ-ray exposure. PMID:26056396

  1. A Transition Zone Showing Highly Discontinuous or Alternating Levels of Stem Cell and Proliferation Markers Characterizes the Development of PTEN-Haploinsufficient Colorectal Cancer.

    PubMed

    Arvai, Kevin J; Hsu, Ya-Hsuan; Lee, Lobin A; Jones, Dan

    2015-01-01

    Stepwise acquisition of oncogene mutations and deletion/inactivation of tumor suppressor genes characterize the development of colorectal cancer (CRC). These genetic events interact with discrete morphologic transitions from hyperplastic mucosa to adenomatous areas, followed by in situ malignant transformation and finally invasive carcinoma. The goal of this study was to identify tissue markers of the adenoma-carcinoma morphogenetic transitions in CRC. We analyzed the patterns of expression of growth regulatory and stem cell markers across these distinct morphologic transition zones in 735 primary CRC tumors. In 202 cases with preserved adenoma-adenocarcinoma transition, we identified, in 37.1% of cases, a zone of adenomatous epithelium, located immediately adjacent to the invasive component, that showed rapidly alternating intraglandular stretches of PTEN+ and PTEN- epithelium. This zone exactly overlapped with similar alternating expression of Ki-67 and inversely with the transforming growth factor-beta (TGF-β) growth regulator SMAD4. These zones also show parallel alternating levels and/or subcellular localization of multiple cancer stem/progenitor cell (CSC) markers, including β-catenin/CTNNB1, ALDH1, and CD44. PTEN was always re-expressed in the invasive tumor in these cases, unlike those with complete loss of PTEN expression. Genomic microarray analysis of CRC with prominent CSC-like expansions demonstrated a high frequency of PTEN genomic deletion/haploinsufficiency in tumors with CSC-like transition zones (62.5%) but not in tumors with downregulated but non-alternating PTEN expression (14.3%). There were no significant differences in the levels of KRAS mutation or CTNNB1 mutation in CSC-like tumors as compared to unselected CRC cases. In conclusion, we have identified a distinctive CSC-like pre-invasive transition zone in PTEN-haploinsufficient CRC that shows convergent on-off regulation of the PTEN/AKT, TGF-β/SMAD and Wnt/β-catenin pathways. This

  2. Maintenance of the marginal-zone B cell compartment specifically requires the RNA-binding protein ZFP36L1.

    PubMed

    Newman, Rebecca; Ahlfors, Helena; Saveliev, Alexander; Galloway, Alison; Hodson, Daniel J; Williams, Robert; Besra, Gurdyal S; Cook, Charlotte N; Cunningham, Adam F; Bell, Sarah E; Turner, Martin

    2017-06-01

    RNA-binding proteins of the ZFP36 family are best known for inhibiting the expression of cytokines through binding to AU-rich elements in the 3' untranslated region and promoting mRNA decay. Here we identified an indispensable role for ZFP36L1 as the regulator of a post-transcriptional hub that determined the identity of marginal-zone B cells by promoting their proper localization and survival. ZFP36L1 controlled a gene-expression program related to signaling, cell adhesion and locomotion; it achieved this in part by limiting expression of the transcription factors KLF2 and IRF8, which are known to enforce the follicular B cell phenotype. These mechanisms emphasize the importance of integrating transcriptional and post-transcriptional processes by RNA-binding proteins for maintaining cellular identity among closely related cell types.

  3. Maintenance of the marginal zone B cell compartment specifically requires the RNA-binding protein ZFP36L1

    PubMed Central

    Newman, Rebecca; Ahlfors, Helena; Saveliev, Alexander; Galloway, Alison; Hodson, Daniel J; Williams, Robert; Besra, Gurdyal S.; Cook, Charlotte N; Cunningham, Adam F; Bell, Sarah E; Turner, Martin

    2017-01-01

    RNA binding proteins (RBP) of the ZFP36 family are best known for inhibiting the expression of cytokines through binding to AU rich elements in the 3’UTR and promoting mRNA decay. Here we show an indispensible role for ZFP36L1 as the regulator of a post-transcriptional hub that determined the identity of marginal zone (MZ) B cells by promoting their proper localization and survival. ZFP36L1 controlled a gene expression program related to signaling, cell-adhesion and locomotion, in part by limiting the expression of the transcription factors KLF2 and IRF8, which are known to enforce the follicular B cell phenotype. These mechanisms emphasize the importance of integrating transcriptional and post-transcriptional processes by RBP for maintaining cellular identity between closely related cell types. PMID:28394372

  4. Developmental-stage-dependent radiosensitivity of neural cells in the ventricular zone of telencephalon in mouse and rat fetuses

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

    Hoshino, K.; Kameyama, Y.

    1988-03-01

    Pregnant ICR mice were treated with single whole-body X-radiation at a dose of 0.24 Gy on day 10, 13, or 15 of gestation. Fetuses were obtained from mothers during 1 and 24 hours after irradiation. Pyknotic cells in the ventricular zone of telencephalon were counted in serial histological sections. Incidence of pyknotic cells peaked during 6 and 9 hours after irradiation in each gestation day group. Then, dose-response curves were obtained 6 hours after 0-0.48 Gy of irradiation. All three dose-response curves showed clear linearity in the dose range lower than 0.24 Gy. Ratios of radiosensitivity estimated from the slopesmore » of dose-response curves in day 10, 13, and 15 groups were 1, 1.4, and 0.4, respectively. These demonstrated that ventricular cells in the day 13 fetal telencephalon were the most radiosensitive among the three different age groups. In order to confirm the presence of the highly radiosensitive stage common to mammalian cerebral cortical histogenesis, pregnant F344 rats were treated with single whole-body gamma-irradiation at a dose of 0.48 Gy on day 13, 14, 15, 17, or 19 of gestation. The incidence of pyknotic cells in the ventricular zone of telencephalon was examined microscopically during 1 and 24 hours after irradiation. The peak incidence was shown 6 hours after irradiation in all the treated groups, and the highest peak incidence was shown in day-15-treated group. The developmental stage of telencephalon of day 15 rat fetuses was comparable to that of day 13 mouse fetuses. Thus, the highest radiosensitivity in terms of acute cell death was shown in the same developmental stage of brain development, i.e., the beginning phase of cerebral cortical histogenesis, in both mice and rats.« less

  5. Immunoarchitectural patterns in nodal marginal zone B-cell lymphoma: a study of 51 cases.

    PubMed

    Salama, Mohamed E; Lossos, Izidore S; Warnke, Roger A; Natkunam, Yasodha

    2009-07-01

    Nodal marginal zone lymphoma (NMZL) represents a rare and heterogeneous group that lacks markers specific for the diagnosis. We evaluated morphologic and immunoarchitectural features of 51 NMZLs, and the following immunostains were performed: CD20, CD21, CD23, CD5, CD3, CD43, CD10, Ki-67, BCL1, BCL2, BCL6, HGAL, and LMO2. Four immunoarchitectural patterns were evident: diffuse (38 [75%]), well-formed nodular/follicular (5 [10%]), interfollicular (7 [14%]), and perifollicular (1 [2%]). Additional features included a monocytoid component (36 [71%]), admixed large cells (20 [39%]), plasma cells (24 [47%]), compartmentalizing stromal sclerosis (13 [25%]), and prominent blood vessel sclerosis (10 [20%]). CD21 highlighted disrupted follicular dendritic cell meshwork in 35 (71%) of 49 cases, and CD43 coexpression was present in 10 (24%) of 42 cases. A panel of germinal center-associated markers was helpful in eliminating cases of diffuse follicle center lymphoma. Our results highlight the histologic and immunoarchitectural spectrum of NMZL and the usefulness of immunohistochemical analysis for CD43, CD23, CD21, BCL6, HGAL, and LMO2 in the diagnosis of NMZL.

  6. Neonatal Subventricular Zone Neural Stem Cells Release Extracellular Vesicles that Act as a Microglial Morphogen.

    PubMed

    Morton, Mary C; Neckles, Victoria N; Seluzicki, Caitlin M; Holmberg, Jennie C; Feliciano, David M

    2018-04-03

    Subventricular zone (SVZ) neural stem cells (NSCs) are the cornerstone of the perinatal neurogenic niche. Microglia are immune cells of the nervous system that are enriched in the neonatal SVZ. Although microglia regulate NSCs, the extent to which this interaction is bi-directional is unclear. Extracellular vesicles (EVs) are cell-derived particles that encase miRNA and proteins. Here, we demonstrate that SVZ NSCs generate and release EVs. Neonatal electroporated fluorescent EV fusion proteins were released by NSCs and subsequently cleared from the SVZ. EVs were preferentially targeted to microglia. Small RNA sequencing identified miRNAs within the EVs that regulate microglia physiology and morphology. EVs induced a transition to a CD11b/Iba1 non-stellate microglial morphology. The transition accompanied a microglial transcriptional state characterized by Let-7-regulated cytokine release and a negative feedback loop that controlled NSC proliferation. These findings implicate an NSC-EV-microglia axis and provide insight to normal and pathophysiological brain development. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  7. Detection of abnormalities in the superficial zone of cartilage repaired using a tissue engineered construct derived from synovial stem cells.

    PubMed

    Ando, Wataru; Fujie, Hiromichi; Moriguchi, Yu; Nansai, Ryosuke; Shimomura, Kazunori; Hart, David A; Yoshikawa, Hideki; Nakamura, Norimasa

    2012-09-28

    The present study investigated the surface structure and mechanical properties of repair cartilage generated from a tissue engineered construct (TEC) derived from synovial mesenchymal stem cells at six months post-implantation compared to those of uninjured cartilage. TEC-mediated repair tissue was cartilaginous with Safranin O staining, and had comparable macro-scale compressive properties with uninjured cartilage. However, morphological assessments revealed that the superficial zone of TEC-mediated tissue was more fibrocartilage-like, in contrast to the middle or deep zones that were more hyaline cartilage-like with Safranin O staining. Histological scoring of the TEC-mediated tissue was significantly lower in the superficial zone than in the middle and deep zones. Scanning electron microscopy showed a thick tangential bundle of collagen fibres at the most superficial layer of uninjured cartilage, while no corresponding structure was detected at the surface of TEC-mediated tissue. Immunohistochemical analysis revealed that PRG4 was localised in the superficial area of uninjured cartilage, as well as the TEC-mediated tissue. Friction testing showed that the lubrication properties of the two tissues was similar, however, micro-indentation analysis revealed that the surface stiffness of the TEC-repair tissue was significantly lower than that of uninjured cartilage. Permeability testing indicated that the TEC-mediated tissue exhibited lower water retaining capacity than did uninjured cartilage, specifically at the superficial zone. Thus, TEC-mediated tissue exhibited compromised mechanical properties at the superficial zone, properties which need improvement in the future for maintenance of long term repair cartilage integrity.

  8. In Situ NAPL Modification for Contaminant Source-Zone Passivation, Mass Flux Reduction, and Remediation

    NASA Astrophysics Data System (ADS)

    Mateas, D. J.; Tick, G.; Carroll, K. C.

    2016-12-01

    A remediation method was developed to reduce the aqueous solubility and mass-flux of target NAPL contaminants through the in-situ creation of a NAPL mixture source-zone. This method was tested in the laboratory using equilibrium batch tests and two-dimensional flow-cell experiments. The creation of two different NAPL mixture source zones were tested in which 1) volumes of relatively insoluble n-hexadecane (HEX) or vegetable oil (VO) were injected into a trichloroethene (TCE) contaminant source-zone; and 2) pre-determined HEX-TCE and VO-TCE mixture ratio source zones were emplaced into the flow cell prior to water flushing. NAPL-aqueous phase batch tests were conducted prior to the flow-cell experiments to evaluate the effects of various NAPL mixture ratios on equilibrium aqueous-phase concentrations of TCE and toluene (TOL) and to design optimal NAPL (HEX or VO) injection volumes for the flow-cell experiments. Uniform NAPL mixture source-zones were able to quickly decrease contaminant mass-flux, as demonstrated by the emplaced source-zone experiments. The success of the HEX and VO injections to also decrease mass flux was dependent on the ability of these injectants to homogeneously mix with TCE source-zone. Upon injection, both HEX and VO migrated away from the source-zone, to some extent. However, the lack of a steady-state dissolution phase and the inefficient mass-flux-reduction/mass-removal behavior produced after VO injection suggest that VO was more effective than HEX for mixing and partitioning within the source-zone region to form a more homogeneous NAPL mixture with TCE. VO appears to be a promising source-zone injectant-NAPL due to its negligible long-term toxicity and lower mobilization potential.

  9. Dynamics of growth zone patterning in the milkweed bug Oncopeltus fasciatus

    PubMed Central

    Weiss, Aryeh; Williams, Terri A.; Nagy, Lisa M.

    2017-01-01

    We describe the dynamic process of abdominal segment generation in the milkweed bug Oncopeltus fasciatus. We present detailed morphological measurements of the growing germband throughout segmentation. Our data are complemented by cell division profiles and expression patterns of key genes, including invected and even-skipped as markers for different stages of segment formation. We describe morphological and mechanistic changes in the growth zone and in nascent segments during the generation of individual segments and throughout segmentation, and examine the relative contribution of newly formed versus existing tissue to segment formation. Although abdominal segment addition is primarily generated through the rearrangement of a pool of undifferentiated cells, there is nonetheless proliferation in the posterior. By correlating proliferation with gene expression in the growth zone, we propose a model for growth zone dynamics during segmentation in which the growth zone is functionally subdivided into two distinct regions: a posterior region devoted to a slow rate of growth among undifferentiated cells, and an anterior region in which segmental differentiation is initiated and proliferation inhibited. PMID:28432218

  10. Expression of Idh1R132H in the Murine Subventricular Zone Stem Cell Niche Recapitulates Features of Early Gliomagenesis.

    PubMed

    Bardella, Chiara; Al-Dalahmah, Osama; Krell, Daniel; Brazauskas, Pijus; Al-Qahtani, Khalid; Tomkova, Marketa; Adam, Julie; Serres, Sébastien; Lockstone, Helen; Freeman-Mills, Luke; Pfeffer, Inga; Sibson, Nicola; Goldin, Robert; Schuster-Böeckler, Benjamin; Pollard, Patrick J; Soga, Tomoyoshi; McCullagh, James S; Schofield, Christopher J; Mulholland, Paul; Ansorge, Olaf; Kriaucionis, Skirmantas; Ratcliffe, Peter J; Szele, Francis G; Tomlinson, Ian

    2016-10-10

    Isocitrate dehydrogenase 1 mutations drive human gliomagenesis, probably through neomorphic enzyme activity that produces D-2-hydroxyglutarate. To model this disease, we conditionally expressed Idh1 R132H in the subventricular zone (SVZ) of the adult mouse brain. The mice developed hydrocephalus and grossly dilated lateral ventricles, with accumulation of 2-hydroxyglutarate and reduced α-ketoglutarate. Stem and transit amplifying/progenitor cell populations were expanded, and proliferation increased. Cells expressing SVZ markers infiltrated surrounding brain regions. SVZ cells also gave rise to proliferative subventricular nodules. DNA methylation was globally increased, while hydroxymethylation was decreased. Mutant SVZ cells overexpressed Wnt, cell-cycle and stem cell genes, and shared an expression signature with human gliomas. Idh1 R132H mutation in the major adult neurogenic stem cell niche causes a phenotype resembling gliomagenesis. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  11. Exogenous retinoic acid induces digit reduction in opossums (Monodelphis domestica) by disrupting cell death and proliferation, and apical ectodermal ridge and zone of polarizing activity function.

    PubMed

    Molineaux, Anna C; Maier, Jennifer A; Schecker, Teresa; Sears, Karen E

    2015-03-01

    Retinoic acid (RA) is a vitamin A derivative. Exposure to exogenous RA generates congenital limb malformations (CLMs) in species from frogs to humans. These CLMs include but are not limited to oligodactyly and long-bone hypoplasia. The processes by which exogenous RA induces CLMs in mammals have been best studied in mouse, but as of yet remain unresolved. We investigated the impact of exogenous RA on the cellular and molecular development of the limbs of a nonrodent model mammal, the opossum Monodelphis domestica. Opossums exposed to exogenous retinoic acid display CLMs including oligodactly, and results are consistent with opossum development being more susceptible to RA-induced disruptions than mouse development. Exposure of developing opossums to exogenous RA leads to an increase in cell death in the limb mesenchyme that is most pronounced in the zone of polarizing activity, and a reduction in cell proliferation throughout the limb mesenchyme. Exogenous RA also disrupts the expression of Shh in the zone of polarizing activity, and Fgf8 in the apical ectodermal ridge, and other genes with roles in the regulation of limb development and cell death. Results are consistent with RA inducing CLMs in opossum limbs by disrupting the functions of the apical ectodermal ridge and zone of polarizing activity, and driving an increase in cell death and reduction of cell proliferation in the mesenchyme of the developing limb. © 2015 Wiley Periodicals, Inc.

  12. Primary cutaneous marginal zone B-cell lymphoma: response to treatment and disease-free survival in a series of 137 patients.

    PubMed

    Servitje, Octavio; Muniesa, Cristina; Benavente, Yolanda; Monsálvez, Verónica; Garcia-Muret, M Pilar; Gallardo, Fernando; Domingo-Domenech, Eva; Lucas, Anna; Climent, Fina; Rodriguez-Peralto, Jose L; Ortiz-Romero, Pablo L; Sandoval, Juan; Pujol, Ramon M; Estrach, M Teresa

    2013-09-01

    Primary cutaneous marginal zone B-cell lymphomas are low-grade lymphomas running an indolent course. Skin relapses have been frequently reported but little information about disease-free survival (DFS) is available. We sought to evaluate relapse rate and DFS in patients with primary cutaneous marginal zone B-cell lymphomas. Clinical features, European Organization for Research and Treatment of Cancer/International Society for Cutaneous Lymphomas stage, light chain restriction, clonality, treatments, skin relapses, DFS, stage progression, extracutaneous disease, and outcome are analyzed in a series of 137 patients. Patients were classified as solitary lesion (T1) (n = 70; 51%), regional skin involvement (T2) (n = 40; 29%), and generalized skin lesions (T3) (n = 27; 20%). Surgical excision, local radiotherapy, or a combination were the initial treatment in 118 patients (86%). In 121 of 137 patients (88%) a complete remission was observed after initial treatment, including 99 of 106 patients (93%) with solitary or localized disease and 22 of 31 patients (71%) with multifocal lesions. Cutaneous relapses were observed in 53 patients (44%). Median DFS was 47 months. Patients with multifocal lesions or T3 disease showed higher relapse rate and shorter DFS. No significant differences were observed between surgery and radiotherapy, but surgery alone was associated with more recurrences at initial site. Overall survival at 5 and 10 years was 93%. Six patients (4%) developed extracutaneous disease during follow-up. This was a case series retrospective study. Our results support long-term follow-up in patients with primary cutaneous marginal zone B-cell lymphomas. Disseminated skin lesions have higher relapse rate and shorter DFS suggesting further investigation on systemic therapies in such a group of patients. Copyright © 2013 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.

  13. Galectin-3 maintains cell motility from the subventricular zone to the olfactory bulb

    PubMed Central

    Comte, Isabelle; Kim, Yongsoo; Young, Christopher C.; van der Harg, Judith M.; Hockberger, Philip; Bolam, Paul J.; Poirier, Françoise; Szele, Francis G.

    2011-01-01

    The adult brain subventricular zone (SVZ) produces neuroblasts that migrate through the rostral migratory stream (RMS) to the olfactory bulb (OB) in a specialized niche. Galectin-3 (Gal-3) regulates proliferation and migration in cancer and is expressed by activated macrophages after brain injury. The function of Gal-3 in the normal brain is unknown, but we serendipitously found that it was expressed by ependymal cells and SVZ astrocytes in uninjured mice. Ependymal cilia establish chemotactic gradients and astrocytes form glial tubes, which combine to aid neuroblast migration. Whole-mount preparations and electron microscopy revealed that both ependymal cilia and SVZ astrocytes were disrupted in Gal3−/− mice. Interestingly, far fewer new BrdU+ neurons were found in the OB of Gal3−/− mice, than in wild-type mice 2 weeks after labeling. However, SVZ proliferation and cell death, as well as OB differentiation rates were unaltered. This suggested that decreased migration in vivo was sufficient to decrease the number of new OB neurons. Two-photon time-lapse microscopy in forebrain slices confirmed decreased migration; cells were slower and more exploratory in Gal3−/− mice. Gal-3 blocking antibodies decreased migration and dissociated neuroblast cell–cell contacts, whereas recombinant Gal-3 increased migration from explants. Finally, we showed that expression of phosphorylated epidermal growth factor receptor (EGFR) was increased in Gal3−/− mice. These results suggest that Gal-3 is important in SVZ neuroblast migration, possibly through an EGFR-based mechanism, and reveals a role for this lectin in the uninjured brain. PMID:21693585

  14. The composition, structure, and stability of guinier-preston zones in lunar and terrestrial orthopyroxene

    USGS Publications Warehouse

    Nord, G.L.

    1980-01-01

    Lunar and terrestrial orthopyroxenes (Mg,Fe,Ca)2Si2O6 contain varying abundances of coherent, Ca-enriched Guinier-Preston (G.P.) zones. G.P. zones 5-6 unit cells thick have been found in one lunar sample whereas all other examples (lunar and terrestrial) are only one unit-cell-thick. Electron diffraction maxima from the larger lunar G.P. zones indicate that d100=18.52 A?? whereas, d100=18.2 A?? for the host. This increase in the a direction corresponds to an increase in calcium content in the G.P. zones over that of the host of ???25 mol% Ca2Si2O6. Diffraction patterns of the hk0 net from an area containing G.P. zones show extra spots (h=2 n+1) not observed in the host orthopyroxene (Pbca), that violate the a-glide of the host. The G.P. zones, therefore, have space group Pbc21 if it is assumed that the c-glide of pyroxene is retained and the space group of the G.P. zone is a subgroup of Pbca. The loss of the a-glide in the G.P. zones results in 4 distinct silica chains and 4 distinct cation sites M1A, M1B, M2A, M2B; by symmetry, equivalent M2A or M2B sites are clustered together in only one-half of the unit cell. As one-fourth of the divalent cations in the G.P. zones are calcium, ordering of Ca on M2A or M2B would produce a zone 9 A?? thick extended parallel to (100) with the composition of Ca(Mg,Fe)Si2O6, but constrained by the host to the structure of orthopyroxene. This zone and the Ca-poor half-unit-cell then constitute an 18 A?? thick G.P. zone. Heating experiments of varying duration indicate that the zones become unstable with respect to the host orthopyroxene at ???950??C for Wo0.6 and ???1,050??C for Wo2.5. The zones are interpreted in terms of the pyroxene subsolidus as a metastable phase having either a solvus relationship with orthopyroxene or originating as a distinct phase. The size, distribution, composition and structure of G.P. zones may be an important indicator of the low-temperature thermal history of orthopyroxene. ?? 1980 Springer-Verlag.

  15. Pharmacological activation of CB2 receptors counteracts the deleterious effect of ethanol on cell proliferation in the main neurogenic zones of the adult rat brain.

    PubMed

    Rivera, Patricia; Blanco, Eduardo; Bindila, Laura; Alen, Francisco; Vargas, Antonio; Rubio, Leticia; Pavón, Francisco J; Serrano, Antonia; Lutz, Beat; Rodríguez de Fonseca, Fernando; Suárez, Juan

    2015-01-01

    Chronic alcohol exposure reduces endocannabinoid activity and disrupts adult neurogenesis in rodents, which results in structural and functional alterations. Cannabinoid receptor agonists promote adult neural progenitor cell (NPC) proliferation. We evaluated the protective effects of the selective CB1 receptor agonist ACEA, the selective CB2 receptor agonist JWH133 and the fatty-acid amide-hydrolase (FAAH) inhibitor URB597, which enhances endocannabinoid receptor activity, on NPC proliferation in rats with forced consumption of ethanol (10%) or sucrose liquid diets for 2 weeks. We performed immunohistochemical and stereological analyses of cells expressing the mitotic phosphorylation of histone-3 (phospho-H3+) and the replicating cell DNA marker 5-bromo-2'-deoxyuridine (BrdU+) in the main neurogenic zones of adult brain: subgranular zone of dentate gyrus (SGZ), subventricular zone of lateral ventricles (SVZ) and hypothalamus. Animals were allowed ad libitum ethanol intake (7.3 ± 1.1 g/kg/day) after a controlled isocaloric pair-feeding period of sucrose and alcoholic diets. Alcohol intake reduced the number of BrdU+ cells in SGZ, SVZ, and hypothalamus. The treatments (URB597, ACEA, JWH133) exerted a differential increase in alcohol consumption over time, but JWH133 specifically counteracted the deleterious effect of ethanol on NPC proliferation in the SVZ and SGZ, and ACEA reversed this effect in the SGZ only. JWH133 also induced an increased number of BrdU+ cells expressing neuron-specific β3-tubulin in the SVZ and SGZ. These results indicated that the specific activation of CB2 receptors rescued alcohol-induced impaired NPC proliferation, which is a potential clinical interest for the risk of neural damage in alcohol dependence.

  16. Pharmacological activation of CB2 receptors counteracts the deleterious effect of ethanol on cell proliferation in the main neurogenic zones of the adult rat brain

    PubMed Central

    Rivera, Patricia; Blanco, Eduardo; Bindila, Laura; Alen, Francisco; Vargas, Antonio; Rubio, Leticia; Pavón, Francisco J.; Serrano, Antonia; Lutz, Beat; Rodríguez de Fonseca, Fernando; Suárez, Juan

    2015-01-01

    Chronic alcohol exposure reduces endocannabinoid activity and disrupts adult neurogenesis in rodents, which results in structural and functional alterations. Cannabinoid receptor agonists promote adult neural progenitor cell (NPC) proliferation. We evaluated the protective effects of the selective CB1 receptor agonist ACEA, the selective CB2 receptor agonist JWH133 and the fatty-acid amide-hydrolase (FAAH) inhibitor URB597, which enhances endocannabinoid receptor activity, on NPC proliferation in rats with forced consumption of ethanol (10%) or sucrose liquid diets for 2 weeks. We performed immunohistochemical and stereological analyses of cells expressing the mitotic phosphorylation of histone-3 (phospho-H3+) and the replicating cell DNA marker 5-bromo-2'-deoxyuridine (BrdU+) in the main neurogenic zones of adult brain: subgranular zone of dentate gyrus (SGZ), subventricular zone of lateral ventricles (SVZ) and hypothalamus. Animals were allowed ad libitum ethanol intake (7.3 ± 1.1 g/kg/day) after a controlled isocaloric pair-feeding period of sucrose and alcoholic diets. Alcohol intake reduced the number of BrdU+ cells in SGZ, SVZ, and hypothalamus. The treatments (URB597, ACEA, JWH133) exerted a differential increase in alcohol consumption over time, but JWH133 specifically counteracted the deleterious effect of ethanol on NPC proliferation in the SVZ and SGZ, and ACEA reversed this effect in the SGZ only. JWH133 also induced an increased number of BrdU+ cells expressing neuron-specific β3-tubulin in the SVZ and SGZ. These results indicated that the specific activation of CB2 receptors rescued alcohol-induced impaired NPC proliferation, which is a potential clinical interest for the risk of neural damage in alcohol dependence. PMID:26483633

  17. Expression of Immunoglobulin Receptors with Distinctive Features Indicating Antigen Selection by Marginal Zone B Cells from Human Spleen

    PubMed Central

    Colombo, Monica; Cutrona, Giovanna; Reverberi, Daniele; Bruno, Silvia; Ghiotto, Fabio; Tenca, Claudya; Stamatopoulos, Kostas; Hadzidimitriou, Anastasia; Ceccarelli, Jenny; Salvi, Sandra; Boccardo, Simona; Calevo, Maria Grazia; De Santanna, Amleto; Truini, Mauro; Fais, Franco; Ferrarini, Manlio

    2013-01-01

    Marginal zone (MZ) B cells, identified as surface (s)IgMhighsIgDlowCD23low/−CD21+CD38− B cells, were purified from human spleens, and the features of their V(D)J gene rearrangements were investigated and compared with those of germinal center (GC), follicular mantle (FM) and switched memory (SM) B cells. Most MZ B cells were CD27+ and exhibited somatic hypermutations (SHM), although to a lower extent than SM B cells. Moreover, among MZ B-cell rearrangements, recurrent sequences were observed, some of which displayed intraclonal diversification. The same diversifying sequences were detected in very low numbers in GC and FM B cells and only when a highly sensitive, gene-specific polymerase chain reaction was used. This result indicates that MZ B cells could expand and diversify in situ and also suggested the presence of a number of activation-induced cytidine deaminase (AID)-expressing B cells in the MZ. The notion of antigen-driven expansion/selection in situ is further supported by the VH CDR3 features of MZ B cells with highly conserved amino acids at specific positions and by the finding of shared (“stereotyped”) sequences in two different spleens. Collectively, the data are consistent with the notion that MZ B cells are a special subset selected by in situ antigenic stimuli. PMID:23877718

  18. Regional analysis of whole cell currents from hair cells of the turtle posterior crista.

    PubMed

    Brichta, Alan M; Aubert, Anne; Eatock, Ruth Anne; Goldberg, Jay M

    2002-12-01

    The turtle posterior crista is made up of two hemicristae, each consisting of a central zone containing type I and type II hair cells and a surrounding peripheral zone containing only type II hair cells and extending from the planum semilunatum to the nonsensory torus. Afferents from various regions of a hemicrista differ in their discharge properties. To see if afferent diversity is related to the basolateral currents of the hair cells innervated, we selectively harvested type I and II hair cells from the central zone and type II hair cells from two parts of the peripheral zone, one near the planum and the other near the torus. Voltage-dependent currents were studied with the whole cell, ruptured-patch method and characterized in voltage-clamp mode. We found regional differences in both outwardly and inwardly rectifying voltage-sensitive currents. As in birds and mammals, type I hair cells have a distinctive outwardly rectifying current (I(K,L)), which begins activating at more hyperpolarized voltages than do the outward currents of type II hair cells. Activation of I(K,L) is slow and sigmoidal. Maximal outward conductances are large. Outward currents in type II cells vary in their activation kinetics. Cells with fast kinetics are associated with small conductances and with partial inactivation during 200-ms depolarizing voltage steps. Almost all type II cells in the peripheral zone and many in the central zone have fast kinetics. Some type II cells in the central zone have large outward currents with slow kinetics and little inactivation. Although these currents resemble I(K,L), they can be distinguished from the latter both electrophysiologically and pharmacologically. There are two varieties of inwardly rectifying currents in type II hair cells: activation of I(K1) is rapid and monoexponential, whereas that of I(h) is slow and sigmoidal. Many type II cells either have both inward currents or only have I(K1); very few cells only have I(h). Inward currents are

  19. gp49B-mediated negative regulation of antibody production by memory and marginal zone B cells.

    PubMed

    Fukao, Saori; Haniuda, Kei; Nojima, Takuya; Takai, Toshiyuki; Kitamura, Daisuke

    2014-07-15

    The rapid Ab responses observed after primary and secondary immunizations are mainly derived from marginal zone (MZ) and memory B cells, respectively, but it is largely unknown how these responses are negatively regulated. Several inhibitory receptors have been identified and their roles have been studied, but mainly on follicular B cells and much less so on MZ B, and never on memory B cells. gp49B is an Ig superfamily member that contains two ITIMs in its cytoplasmic tail, and it has been shown to negatively regulate mast cell, macrophage, and NK cell responses. In this study, we demonstrate that gp49B is preferentially expressed on memory and MZ B cells. We show that gp49B(-/-) mice produce more IgM after a primary immunization and more IgM and IgG1 after a secondary immunization than gp49B(+/+) mice in T cell-dependent immune responses. Memory and MZ B cells from gp49B(-/-) mice also produce more Abs upon in vitro stimulation with CD40 than those from gp49B(+/+) mice. The in vitro IgM production by MZ B cells from gp49B(+/+), but not gp49B(-/-), mice is suppressed by interaction with a putative gp49B ligand, the integrin αvβ3 heterodimer. In addition, gp49B(-/-) mice exhibited exaggerated IgE production in the memory recall response. These results suggest that plasma cell development from memory and MZ B cells, as well as subsequent Ab production, are suppressed via gp49B. In memory B cells, this suppression also prevents excessive IgE production, thus curtailing allergic diseases. Copyright © 2014 by The American Association of Immunologists, Inc.

  20. Novel calcium recognition constructions in proteins: Calcium blade and EF-hand zone

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

    Denesyuk, Alexander I., E-mail: adenesyu@abo.fi; Institute for Biological Instrumentation of the Russian Academy of Sciences, Pushchino 142290; Permyakov, Sergei E.

    Metal ions can regulate various cell processes being first, second or third messengers, and some of them, especially transition metal ions, take part in catalysis in many enzymes. As an intracellular ion, Ca{sup 2+} is involved in many cellular functions from fertilization and contraction, cell differentiation and proliferation, to apoptosis and cancer. Here, we have identified and described two novel calcium recognition environments in proteins: the calcium blade zone and the EF-hand zone, common to 12 and 8 different protein families, respectively. Each of the two environments contains three distinct structural elements: (a) the well-known characteristic Dx[DN]xDG motif; (b) anmore » adjacent structurally identical segment, which binds metal ion in the same way between the calcium blade zone and the EF-hand zone; and (c) the following structurally variable segment, which distinguishes the calcium blade zone from the EF-hand zone. Both zones have sequence insertions between the last residue of the zone and calcium-binding residues in positions V or VI. The long insertion often connects the active and the calcium-binding sites in proteins. Using the structurally identical segments as an anchor, we were able to construct the classical calmodulin type EF-hand calcium-binding site out of two different calcium-binding motifs from two unrelated proteins.« less

  1. Store-Operated Calcium Entries Control Neural Stem Cell Self-Renewal in the Adult Brain Subventricular Zone.

    PubMed

    Domenichini, Florence; Terrié, Elodie; Arnault, Patricia; Harnois, Thomas; Magaud, Christophe; Bois, Patrick; Constantin, Bruno; Coronas, Valérie

    2018-05-01

    The subventricular zone (SVZ) is the major stem cell niche in the brain of adult mammals. Within this region, neural stem cells (NSC) proliferate, self-renew and give birth to neurons and glial cells. Previous studies underlined enrichment in calcium signaling-related transcripts in adult NSC. Because of their ability to mobilize sustained calcium influxes in response to a wide range of extracellular factors, store-operated channels (SOC) appear to be, among calcium channels, relevant candidates to induce calcium signaling in NSC whose cellular activities are continuously adapted to physiological signals from the microenvironment. By Reverse Transcription Polymerase Chain Reaction (RT-PCR), Western blotting and immunocytochemistry experiments, we demonstrate that SVZ cells express molecular actors known to build up SOC, namely transient receptor potential canonical 1 (TRPC1) and Orai1, as well as their activator stromal interaction molecule 1 (STIM1). Calcium imaging reveals that SVZ cells display store-operated calcium entries. Pharmacological blockade of SOC with SKF-96365 or YM-58483 (also called BTP2) decreases proliferation, impairs self-renewal by shifting the type of SVZ stem cell division from symmetric proliferative to asymmetric, thereby reducing the stem cell population. Brain section immunostainings show that TRPC1, Orai1, and STIM1 are expressed in vivo, in SOX2-positive SVZ NSC. Injection of SKF-96365 in brain lateral ventricle diminishes SVZ cell proliferation and reduces the ability of SVZ cells to form neurospheres in vitro. The present study combining in vitro and in vivo approaches uncovers a major role for SOC in the control of SVZ NSC population and opens new fields of investigation for stem cell biology in health and disease. Stem Cells 2018;36:761-774. © AlphaMed Press 2018.

  2. Functional and Evolutionary Analysis of the CASPARIAN STRIP MEMBRANE DOMAIN PROTEIN Family1[C][W

    PubMed Central

    Roppolo, Daniele; Boeckmann, Brigitte; Pfister, Alexandre; Boutet, Emmanuel; Rubio, Maria C.; Dénervaud-Tendon, Valérie; Vermeer, Joop E.M.; Gheyselinck, Jacqueline; Xenarios, Ioannis; Geldner, Niko

    2014-01-01

    CASPARIAN STRIP MEMBRANE DOMAIN PROTEINS (CASPs) are four-membrane-span proteins that mediate the deposition of Casparian strips in the endodermis by recruiting the lignin polymerization machinery. CASPs show high stability in their membrane domain, which presents all the hallmarks of a membrane scaffold. Here, we characterized the large family of CASP-like (CASPL) proteins. CASPLs were found in all major divisions of land plants as well as in green algae; homologs outside of the plant kingdom were identified as members of the MARVEL protein family. When ectopically expressed in the endodermis, most CASPLs were able to integrate the CASP membrane domain, which suggests that CASPLs share with CASPs the propensity to form transmembrane scaffolds. Extracellular loops are not necessary for generating the scaffold, since CASP1 was still able to localize correctly when either one of the extracellular loops was deleted. The CASP first extracellular loop was found conserved in euphyllophytes but absent in plants lacking Casparian strips, an observation that may contribute to the study of Casparian strip and root evolution. In Arabidopsis (Arabidopsis thaliana), CASPL showed specific expression in a variety of cell types, such as trichomes, abscission zone cells, peripheral root cap cells, and xylem pole pericycle cells. PMID:24920445

  3. Functional and Evolutionary Analysis of the CASPARIAN STRIP MEMBRANE DOMAIN PROTEIN Family.

    PubMed

    Roppolo, Daniele; Boeckmann, Brigitte; Pfister, Alexandre; Boutet, Emmanuel; Rubio, Maria C; Dénervaud-Tendon, Valérie; Vermeer, Joop E M; Gheyselinck, Jacqueline; Xenarios, Ioannis; Geldner, Niko

    2014-08-01

    CASPARIAN STRIP MEMBRANE DOMAIN PROTEINS (CASPs) are four-membrane-span proteins that mediate the deposition of Casparian strips in the endodermis by recruiting the lignin polymerization machinery. CASPs show high stability in their membrane domain, which presents all the hallmarks of a membrane scaffold. Here, we characterized the large family of CASP-like (CASPL) proteins. CASPLs were found in all major divisions of land plants as well as in green algae; homologs outside of the plant kingdom were identified as members of the MARVEL protein family. When ectopically expressed in the endodermis, most CASPLs were able to integrate the CASP membrane domain, which suggests that CASPLs share with CASPs the propensity to form transmembrane scaffolds. Extracellular loops are not necessary for generating the scaffold, since CASP1 was still able to localize correctly when either one of the extracellular loops was deleted. The CASP first extracellular loop was found conserved in euphyllophytes but absent in plants lacking Casparian strips, an observation that may contribute to the study of Casparian strip and root evolution. In Arabidopsis (Arabidopsis thaliana), CASPL showed specific expression in a variety of cell types, such as trichomes, abscission zone cells, peripheral root cap cells, and xylem pole pericycle cells. © 2014 American Society of Plant Biologists. All Rights Reserved.

  4. Zone separator for multiple zone vessels

    DOEpatents

    Jones, John B.

    1983-02-01

    A solids-gas contact vessel, having two vertically disposed distinct reaction zones, includes a dynamic seal passing solids from an upper to a lower zone and maintaining a gas seal against the transfer of the separate treating gases from one zone to the other, and including a stream of sealing fluid at the seal.

  5. Identifying the transition to the maturation zone in three ecotypes of Arabidopsis thaliana roots.

    PubMed

    Cajero Sánchez, Wendy; García-Ponce, Berenice; Sánchez, María de la Paz; Álvarez-Buylla, Elena R; Garay-Arroyo, Adriana

    2018-01-01

    The Arabidopsis thaliana (hereafter Arabidopsis) root has become a useful model for studying how organ morphogenesis emerge from the coordination and balance of cell proliferation and differentiation, as both processes may be observed and quantified in the root at different stages of development. Hence, being able to objectively identify and delimit the different stages of root development has been very important. Up to now, three different zones along the longitudinal axis of the primary root of Arabidopsis, have been identified: the root apical meristematic zone (RAM) with two domains [the proliferative (PD) and the transition domain (TD)], the elongation zone (EZ) and the maturation zone (MZ). We previously reported a method to quantify the length of the cells of the meristematic and the elongation zone, as well as the boundaries or transitions between the root domains along the growing part of the Arabidopsis root. In this study, we provide a more accurate criterion to identify the MZ. Traditionally, the transition between the EZ to the MZ has been established by the emergence of the first root-hair bulge in the epidermis, because this emergence coincides with cell maturation in this cell type. But we have found here that after the emergence of the first root-hair bulge some cells continue to elongate and we have confirmed this in three different Arabidopsis ecotypes. We established the limit between the EZ and the MZ by looking for the closest cortical cell with a longer length than the average cell length of 10 cells after the cortical cell closest to the epidermal cell with the first root-hair bulge in these three ecotypes. In Col-0 and Ws this cell is four cells above the one with the root hair bulge and, in the Ler ecotype, this cell is five cells above. To unambiguously identifying the site at which cells stop elongating and attain their final length and fate at the MZ, we propose to calculate the length of completely elongated cortical cells counting 10

  6. Identifying the transition to the maturation zone in three ecotypes of Arabidopsis thaliana roots

    PubMed Central

    Cajero Sánchez, Wendy; García-Ponce, Berenice; Sánchez, María de la Paz; Álvarez-Buylla, Elena R.; Garay-Arroyo, Adriana

    2018-01-01

    ABSTRACT The Arabidopsis thaliana (hereafter Arabidopsis) root has become a useful model for studying how organ morphogenesis emerge from the coordination and balance of cell proliferation and differentiation, as both processes may be observed and quantified in the root at different stages of development. Hence, being able to objectively identify and delimit the different stages of root development has been very important. Up to now, three different zones along the longitudinal axis of the primary root of Arabidopsis, have been identified: the root apical meristematic zone (RAM) with two domains [the proliferative (PD) and the transition domain (TD)], the elongation zone (EZ) and the maturation zone (MZ). We previously reported a method to quantify the length of the cells of the meristematic and the elongation zone, as well as the boundaries or transitions between the root domains along the growing part of the Arabidopsis root. In this study, we provide a more accurate criterion to identify the MZ. Traditionally, the transition between the EZ to the MZ has been established by the emergence of the first root-hair bulge in the epidermis, because this emergence coincides with cell maturation in this cell type. But we have found here that after the emergence of the first root-hair bulge some cells continue to elongate and we have confirmed this in three different Arabidopsis ecotypes. We established the limit between the EZ and the MZ by looking for the closest cortical cell with a longer length than the average cell length of 10 cells after the cortical cell closest to the epidermal cell with the first root-hair bulge in these three ecotypes. In Col-0 and Ws this cell is four cells above the one with the root hair bulge and, in the Ler ecotype, this cell is five cells above. To unambiguously identifying the site at which cells stop elongating and attain their final length and fate at the MZ, we propose to calculate the length of completely elongated cortical cells

  7. Expression of Tlx in both stem cells and transit amplifying progenitors regulates stem cell activation and differentiation in the neonatal lateral subependymal zone.

    PubMed

    Obernier, Kirsten; Simeonova, Ina; Fila, Tatiana; Mandl, Claudia; Hölzl-Wenig, Gabriele; Monaghan-Nichols, Paula; Ciccolini, Francesca

    2011-09-01

    Niche homeostasis in the postnatal subependymal zone of the lateral ventricle (lSEZ) requires coordinated proliferation and differentiation of neural progenitor cells. The mechanisms regulating this balance are scarcely known. Recent observations indicate that the orphan nuclear receptor Tlx is an intrinsic factor essential in maintaining this balance. However, the effect of Tlx on gene expression depends on age and cell-type cues. Therefore, it is essential to establish its expression pattern at different developmental ages. Here, we show for the first time that in the neonatal lSEZ activated neural stem cells (NSCs) and especially transit-amplifying progenitors (TAPs) express Tlx and that its expression may be regulated at the posttranscriptional level. We also provide evidence that in both cell types Tlx affects gene expression in a positive and negative manner. In activated NSCs, but not in TAPs, absence of Tlx leads to overexpression of negative cell cycle regulators and impairment of proliferation. Moreover, in both cell types, the homeobox transcription factor Dlx2 is downregulated in the absence of Tlx. This is paralleled by increased expression of Olig2 in activated NSCs and glial fibrillary acidic protein in TAPs, indicating that in both populations Tlx decreases gliogenesis. Consistent with this, we found a higher proportion of cells expressing glial makers in the neonatal lSEZ of mutant mice than in the wild type counterpart. Thus, Tlx playing a dual role affects the expression of distinct genes in these two lSEZ cell types. Copyright © 2011 AlphaMed Press.

  8. Vadose zone water fluxmeter

    DOEpatents

    Faybishenko, Boris A.

    2005-10-25

    A Vadose Zone Water Fluxmeter (WFM) or Direct Measurement WFM provides direct measurement of unsaturated water flow in the vadose zone. The fluxmeter is a cylindrical device that fits in a borehole or can be installed near the surface, or in pits, or in pile structures. The fluxmeter is primarily a combination of tensiometers and a porous element or plate in a water cell that is used for water injection or extraction under field conditions. The same water pressure measured outside and inside of the soil sheltered by the lower cylinder of the fluxmeter indicates that the water flux through the lower cylinder is similar to the water flux in the surrounding soil. The fluxmeter provides direct measurement of the water flow rate in the unsaturated soils and then determines the water flux, i.e. the water flow rate per unit area.

  9. Expression of nestin and chromogranin in regeneration zones of rat pancreas.

    PubMed

    Ege, Bahadir; Dinc, Tolga; Kayilioglu, Selami Ilgaz; Tezel, Ekmel; Ersoy, Emin

    2017-01-01

    The particular signals that start and orchestrate the regeneration process in pancreas are not well understood yet. We aimed to investigate the expression of nestin and chromogranin A in pancreatic regeneration zones and a secondary objective, we assessed the efficiency of pancreatic duct ligation method in creation of a pancreatic regeneration model in rats. Partial (90%) pancreatectomy and pancreatic duct ligation were performed in Wistar rats, in order to create pancreatic regeneration models. Pancreatic tissues were examined histologically. Expression profiles were investigated by immunohistochemistry for nestin and chromogranin A. Nestin and chromogranin A expressions were observed in regeneration zones. Pancreatic regenerations zones were seen in pancreatic duct ligation group samples as well as partial pancreatectomy group. Nestin was expressed prominently in acinoductular metaplasia cells in regeneration zones. This was best demonstrated in the samples of pancreatic duct ligation group. In the subsequent sections of nestin positive sites, cytoplasmic positivity with chromogranin A was observed. This study confirms that nestin and chromogranin A can be detected in neogenesis-evoked pancreatic tissue, particularly in the acinoductular epithelium. Nestin and chromogranin A may be important markers to identify pancreatic stem cells. Pancreatic duct ligation can be used for creating pancreatic regeneration model in rats. Chromogranin A, Nestin, Pancreas, Regeneration, Stem cells.

  10. The number of stem cells in the subependymal zone of the adult rodent brain is correlated with the number of ependymal cells and not with the volume of the niche.

    PubMed

    Kazanis, Ilias; Ffrench-Constant, Charles

    2012-05-01

    The mammalian subependymal zone (SEZ; often called subventricular) situated at the lateral walls of the lateral ventricles of the brain contains a pool of relatively quiescent adult neural stem cells whose neurogenic activity persists throughout life. These stem cells are positioned in close proximity both to the ependymal cells that provide the cerebrospinal fluid interface and to the blood vessel endothelial cells, but the relative contribution of these 2 cell types to stem cell regulation remains undetermined. Here, we address this question by analyzing a naturally occurring example of volumetric scaling of the SEZ in a comparison of the mouse SEZ with the larger rat SEZ. Our analysis reveals that the number of stem cells in the SEZ niche is correlated with the number of ependymal cells rather than with the volume, thereby indicating the importance of ependymal-derived factors in the formation and function of the SEZ. The elucidation of the factors generated by ependymal cells that regulate stem cell numbers within the SEZ is, therefore, of importance for stem cell biology and regenerative neuroscience.

  11. Neurotransmitters couple brain activity to subventricular zone neurogenesis

    PubMed Central

    Young, Stephanie Z.; Taylor, M. Morgan; Bordey, Angélique

    2011-01-01

    Adult neurogenesis occurs in two privileged microenvironments, the hippocampal subgranular zone of the dentate gyrus and the subventricular zone (SVZ) along the lateral ventricle. This review focuses on accumulating evidence suggesting that the activity of specific brain regions or bodily states influences SVZ cell proliferation and neurogenesis. Neuromodulators such as dopamine and serotonin have been shown to have long-range effects through neuronal projections into the SVZ. Local GABA and glutamate signaling have demonstrated effects on SVZ proliferation and neurogenesis, but an extra-niche source of these neurotransmitters remains to be explored and options will be discussed. There is also accumulating evidence that diseases and bodily states such as Alzheimer's disease, seizures, sleep, and pregnancy influence SVZ cell proliferation. With such complex behavior and environmentally-driven factors that control subregion-specific activity, it will become necessary to account for overlapping roles of multiple neurotransmitter systems on neurogenesis when developing cell therapies or drug treatments. PMID:21395856

  12. 77 FR 25133 - Foreign-Trade Zone 126, Temporary/Interim Manufacturing Authority, Brightpoint North America L.P...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-27

    ... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Docket T-3-2012] Foreign-Trade Zone 126, Temporary/Interim Manufacturing Authority, Brightpoint North America L.P. (Cell Phone Kitting and... America L.P., to produce cell phone kits under FTZ procedures within FTZ 126--Site 23, in Reno, Nevada...

  13. Blastic marginal zone lymphoma: a clinical and pathological study of 8 cases and review of the literature.

    PubMed

    Magro, Cynthia M; Yang, Amy; Fraga, Garth

    2013-05-01

    Blastic transformation (BT) of marginal zone lymphoma or mucosa-associated lymphoid tissue lymphoma has been mainly reported in the spleen and stomach. Primary cutaneous marginal zone lymphoma that undergoes BT is rare and not well documented. We describe 8 patients with blastic primary cutaneous marginal zone lymphoma and compare the clinical, pathologic, and molecular findings of these patients with 10 cases previously reported in the literature. The cases of blastic marginal zone lymphoma could be categorized into cases of de novo blastic marginal zone lymphoma and large-cell transformation arising in a background of a history of biopsy proven marginal zone lymphoma. The cases of de novo blastic marginal zone lymphoma occurred in elderly patients without any medical history. In each of the cases, the lesions were radiated, not treated, or treated with complete excision without any death due to lymphoma nor was there any evidence of extracutaneous dissemination. Large-cell transformation arising in background of marginal zone lymphoma typically occurred in patients who were younger; 2 of the 4 cases were immunocompromised. The clinical course in each of the cases was aggressive with 3 of the 4 patients succumbing to disseminated disease while 1 patient developed extracutaneous nodal disease. Phenotypically, there was an expression of CD5 in a total of 3 of the 8 cases and CD23 in 3 of the 8 cases. Commonality of B-cell clones was demonstrated in 2 cases where biopsies were available of both the less aggressive appearing marginal zone lymphoma and the transformed biopsies. Cytogenetic abnormalities associated with BT included a deletion of chromosome 7q in all cases tested. Large-cell transformation arising in a patient with a history of marginal zone lymphoma portends a worse prognosis, including death from disseminated disease, whereas a de novo presentation of blastic marginal zone lymphoma may define a clinical course similar to other forms of low

  14. Movement of endogenous calcium in the elongating zone of graviresponding roots of Zea mays

    NASA Technical Reports Server (NTRS)

    Moore, R.; Cameron, I. L.; Smith, N. K.

    1989-01-01

    Endogenous calcium (Ca) accumulates along the lower side of the elongating zone of horizontally oriented roots of Zea mays cv. Yellow Dent. This accumulation of Ca correlates positively with the onset of gravicurvature, and occurs in the cytoplasm, cell walls and mucilage of epidermal cells. Corresponding changes in endogenous Ca do not occur in cortical cells of the elongating zone of intact roots. These results indicate that the calcium asymmetries associated with root gravicurvature occur in the outermost layers of the root.

  15. CCR6 Defines Memory B Cell Precursors in Mouse and Human Germinal Centers, Revealing Light-Zone Location and Predominant Low Antigen Affinity.

    PubMed

    Suan, Dan; Kräutler, Nike J; Maag, Jesper L V; Butt, Danyal; Bourne, Katherine; Hermes, Jana R; Avery, Danielle T; Young, Clara; Statham, Aaron; Elliott, Michael; Dinger, Marcel E; Basten, Antony; Tangye, Stuart G; Brink, Robert

    2017-12-19

    Memory B cells (MBCs) and plasma cells (PCs) constitute the two cellular outputs of germinal center (GC) responses that together facilitate long-term humoral immunity. Although expression of the transcription factor BLIMP-1 identifies cells undergoing PC differentiation, no such marker exists for cells committed to the MBC lineage. Here, we report that the chemokine receptor CCR6 uniquely marks MBC precursors in both mouse and human GCs. CCR6 + GC B cells were highly enriched within the GC light zone (LZ), were the most quiescent of all GC B cells, exhibited a cell-surface phenotype and gene expression signature indicative of an MBC transition, and possessed the augmented response characteristics of MBCs. MBC precursors within the GC LZ predominantly possessed a low affinity for antigen but also included cells from within the high-affinity pool. These data indicate a fundamental dichotomy between the processes that drive MBC and PC differentiation during GC responses. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Genetically Engineered Lymphocytes, Cyclophosphamide, and Aldesleukin in Treating Patients With Relapsed or Refractory Mantle Cell Lymphoma or Indolent B-Cell Non-Hodgkin Lymphoma

    ClinicalTrials.gov

    2014-08-04

    B-cell Chronic Lymphocytic Leukemia; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Nodal Marginal Zone B-cell Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Small Lymphocytic Lymphoma; Refractory Chronic Lymphocytic Leukemia; Splenic Marginal Zone Lymphoma; Waldenström Macroglobulinemia

  17. Revisiting the B-cell compartment in mouse and humans: more than one B-cell subset exists in the marginal zone and beyond.

    PubMed

    Garraud, Olivier; Borhis, Gwenoline; Badr, Gamal; Degrelle, Séverine; Pozzetto, Bruno; Cognasse, Fabrice; Richard, Yolande

    2012-11-29

    describe novel findings regarding the B-cell compartments found in the mouse as a model organism, and in human physiology and pathology. It must be emphasised that some differences are noticeable between the mouse and human systems, thus increasing the complexity of B-cell compartmentalisation. Special attention will be given to the (lymph node and spleen) marginal zones, which represent major crossroads for B-cell types and functions and a challenge for understanding better the role of B-cell specificities in innate and adaptive immunology.

  18. Area-Specific Regulation of Quiescent Neural Stem Cells by Notch3 in the Adult Mouse Subependymal Zone.

    PubMed

    Kawai, Hiroki; Kawaguchi, Daichi; Kuebrich, Benjamin D; Kitamoto, Takeo; Yamaguchi, Masahiro; Gotoh, Yukiko; Furutachi, Shohei

    2017-12-06

    In the adult mammalian brain, neural stem cells (NSCs) generate new neurons throughout the mammal's lifetime. The balance between quiescence and active cell division among NSCs is crucial in producing appropriate numbers of neurons while maintaining the stem cell pool for a long period. The Notch signaling pathway plays a central role in both maintaining quiescent NSCs (qNSCs) and promoting cell division of active NSCs (aNSCs), although no one knows how this pathway regulates these apparently opposite functions. Notch1 has been shown to promote proliferation of aNSCs without affecting qNSCs in the adult mouse subependymal zone (SEZ). In this study, we found that Notch3 is expressed to a higher extent in qNSCs than in aNSCs while Notch1 is preferentially expressed in aNSCs and transit-amplifying progenitors in the adult mouse SEZ. Furthermore, Notch3 is selectively expressed in the lateral and ventral walls of the SEZ. Knockdown of Notch3 in the lateral wall of the adult SEZ increased the division of NSCs. Moreover, deletion of the Notch3 gene resulted in significant reduction of qNSCs specifically in the lateral and ventral walls, compared with the medial and dorsal walls, of the lateral ventricles. Notch3 deletion also reduced the number of qNSCs activated after antimitotic cytosine β-D-arabinofuranoside (Ara-C) treatment. Importantly, Notch3 deletion preferentially reduced specific subtypes of newborn neurons in the olfactory bulb derived from the lateral walls of the SEZ. These results indicate that Notch isoforms differentially control the quiescent and proliferative steps of adult SEZ NSCs in a domain-specific manner. SIGNIFICANCE STATEMENT In the adult mammalian brain, the subependymal zone (SEZ) of the lateral ventricles is the largest neurogenic niche, where neural stem cells (NSCs) generate neurons. In this study, we found that Notch3 plays an important role in the maintenance of quiescent NSCs (qNSCs), while Notch1 has been reported to act as a regulator

  19. Cross-regulation between Aurora B and Citron kinase controls midbody architecture in cytokinesis

    PubMed Central

    McKenzie, Callum; Bassi, Zuni I.; Debski, Janusz; Gottardo, Marco; Callaini, Giuliano; Dadlez, Michal; D'Avino, Pier Paolo

    2016-01-01

    Cytokinesis culminates in the final separation, or abscission, of the two daughter cells at the end of cell division. Abscission relies on an organelle, the midbody, which forms at the intercellular bridge and is composed of various proteins arranged in a precise stereotypic pattern. The molecular mechanisms controlling midbody organization and function, however, are obscure. Here we show that proper midbody architecture requires cross-regulation between two cell division kinases, Citron kinase (CIT-K) and Aurora B, the kinase component of the chromosomal passenger complex (CPC). CIT-K interacts directly with three CPC components and is required for proper midbody architecture and the orderly arrangement of midbody proteins, including the CPC. In addition, we show that CIT-K promotes Aurora B activity through phosphorylation of the INCENP CPC subunit at the TSS motif. In turn, Aurora B controls CIT-K localization and association with its central spindle partners through phosphorylation of CIT-K's coiled coil domain. Our results identify, for the first time, a cross-regulatory mechanism between two kinases during cytokinesis, which is crucial for establishing the stereotyped organization of midbody proteins. PMID:27009191

  20. Comparative Analysis of the Subventricular Zone in Rat, Ferret and Macaque: Evidence for an Outer Subventricular Zone in Rodents

    PubMed Central

    Camacho, Jasmin; Antczak, Jared L.; Prakash, Anish N.; Cziep, Matthew E.; Walker, Anita I.; Noctor, Stephen C.

    2012-01-01

    The mammalian cerebral cortex arises from precursor cells that reside in a proliferative region surrounding the lateral ventricles of the developing brain. Recent work has shown that precursor cells in the subventricular zone (SVZ) provide a major contribution to prenatal cortical neurogenesis, and that the SVZ is significantly thicker in gyrencephalic mammals such as primates than it is in lissencephalic mammals including rodents. Identifying characteristics that are shared by or that distinguish cortical precursor cells across mammalian species will shed light on factors that regulate cortical neurogenesis and may point toward mechanisms that underlie the evolutionary expansion of the neocortex in gyrencephalic mammals. We immunostained sections of the developing cerebral cortex from lissencephalic rats, and from gyrencephalic ferrets and macaques to compare the distribution of precursor cell types in each species. We also performed time-lapse imaging of precursor cells in the developing rat neocortex. We show that the distribution of Pax6+ and Tbr2+ precursor cells is similar in lissencephalic rat and gyrencephalic ferret, and different in the gyrencephalic cortex of macaque. We show that mitotic Pax6+ translocating radial glial cells (tRG) are present in the cerebral cortex of each species during and after neurogenesis, demonstrating that the function of Pax6+ tRG cells is not restricted to neurogenesis. Furthermore, we show that Olig2 expression distinguishes two distinct subtypes of Pax6+ tRG cells. Finally we present a novel method for discriminating the inner and outer SVZ across mammalian species and show that the key cytoarchitectural features and cell types that define the outer SVZ in developing primates are present in the developing rat neocortex. Our data demonstrate that the developing rat cerebral cortex possesses an outer subventricular zone during late stages of cortical neurogenesis and that the developing rodent cortex shares important features

  1. Comparative analysis of the subventricular zone in rat, ferret and macaque: evidence for an outer subventricular zone in rodents.

    PubMed

    Martínez-Cerdeño, Verónica; Cunningham, Christopher L; Camacho, Jasmin; Antczak, Jared L; Prakash, Anish N; Cziep, Matthew E; Walker, Anita I; Noctor, Stephen C

    2012-01-01

    The mammalian cerebral cortex arises from precursor cells that reside in a proliferative region surrounding the lateral ventricles of the developing brain. Recent work has shown that precursor cells in the subventricular zone (SVZ) provide a major contribution to prenatal cortical neurogenesis, and that the SVZ is significantly thicker in gyrencephalic mammals such as primates than it is in lissencephalic mammals including rodents. Identifying characteristics that are shared by or that distinguish cortical precursor cells across mammalian species will shed light on factors that regulate cortical neurogenesis and may point toward mechanisms that underlie the evolutionary expansion of the neocortex in gyrencephalic mammals. We immunostained sections of the developing cerebral cortex from lissencephalic rats, and from gyrencephalic ferrets and macaques to compare the distribution of precursor cell types in each species. We also performed time-lapse imaging of precursor cells in the developing rat neocortex. We show that the distribution of Pax6+ and Tbr2+ precursor cells is similar in lissencephalic rat and gyrencephalic ferret, and different in the gyrencephalic cortex of macaque. We show that mitotic Pax6+ translocating radial glial cells (tRG) are present in the cerebral cortex of each species during and after neurogenesis, demonstrating that the function of Pax6+ tRG cells is not restricted to neurogenesis. Furthermore, we show that Olig2 expression distinguishes two distinct subtypes of Pax6+ tRG cells. Finally we present a novel method for discriminating the inner and outer SVZ across mammalian species and show that the key cytoarchitectural features and cell types that define the outer SVZ in developing primates are present in the developing rat neocortex. Our data demonstrate that the developing rat cerebral cortex possesses an outer subventricular zone during late stages of cortical neurogenesis and that the developing rodent cortex shares important features

  2. The role of stem-cell transplantation in the treatment of marginal zone lymphoma.

    PubMed

    Shimoni, Avichai

    High-dose chemotherapy and autologous stem-cell transplantation (ASCT) is standard therapy in relapsed/refractory aggressive lymphoma. The optimal therapy of relapsed/refractory disseminated marginal-zone lymphoma (MZL) has not been defined. Limited data on ASCT in this setting suggests outcomes are similar to what is expected in follicular lymphoma. International guidelines suggest that ASCT should be considered in follicular lymphoma in second or subsequent remission, in particular in high-risk disease, or following disease transformation. These guidelines can be extrapolated to MZL. ASCT is not considered curative but a subset of patients achieve very long remissions. The major concern is the occurrence of secondary malignancies possibly related to total-body irradiation. Allogeneic SCT is usually considered after failure of ASCT, but can also be considered upfront in younger patients seeking curative approach. The introduction of novel/targeted therapies may change the role and timing SCT may have in the treatment algorithm of indolent lymphomas. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Gastric marginal zone lymphoma of mucosa-associated lymphoid tissue and signet ring cell carcinoma, synchronous collision tumour of the stomach: a case report.

    PubMed

    George, Smiley Annie; Junaid, T A

    2014-01-01

    To report a rare case of synchronous marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) signet ring cell carcinoma occurring as a collision tumour in the stomach. A 53-year-old man was diagnosed initially with signet ring cell carcinoma of the stomach. The microscopy of the subsequent total gastrectomy revealed a collision tumour of MALT lymphoma and signet ring cell carcinoma associated with Helicobacter pylori gastritis. This case highlighted the importance of a careful evaluation of the accompanying lymphoid population in the biopsy samples of gastric adenocarcinoma and underlined the need for multiple endoscopic biopsies to detect these rare synchronous tumours. © 2013 S. Karger AG, Basel.

  4. Gastric Marginal Zone Lymphoma of Mucosa-Associated Lymphoid Tissue and Signet Ring Cell Carcinoma, Synchronous Collision Tumour of the Stomach: A Case Report

    PubMed Central

    George, Smiley Annie; Junaid, T.A.

    2014-01-01

    Objective To report a rare case of synchronous marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) signet ring cell carcinoma occurring as a collision tumour in the stomach. Clinical Presentation and Intervention A 53-year-old man was diagnosed initially with signet ring cell carcinoma of the stomach. The microscopy of the subsequent total gastrectomy revealed a collision tumour of MALT lymphoma and signet ring cell carcinoma associated with Helicobacter pylori gastritis. Conclusion This case highlighted the importance of a careful evaluation of the accompanying lymphoid population in the biopsy samples of gastric adenocarcinoma and underlined the need for multiple endoscopic biopsies to detect these rare synchronous tumours. PMID:24247357

  5. Vadose zone microbiology

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

    Kieft, Thomas L.; Brockman, Fred J.

    2001-01-17

    The vadose zone is defined as the portion of the terrestrial subsurface that extends from the land surface downward to the water table. As such, it comprises the surface soil (the rooting zone), the underlying subsoil, and the capillary fringe that directly overlies the water table. The unsaturated zone between the rooting zone and the capillary fringe is termed the "intermediate zone" (Chapelle, 1993). The vadose zone has also been defined as the unsaturated zone, since the sediment pores and/or rock fractures are generally not completely water filled, but instead contain both water and air. The latter characteristic results inmore » the term "zone of aeration" to describe the vadose zone. The terms "vadose zone," "unsaturated zone", and "zone of aeration" are nearly synonymous, except that the vadose zone may contain regions of perched water that are actually saturated. The term "subsoil" has also been used for studies of shallow areas of the subsurface immediately below the rooting zone. This review focuses almost exclusively on the unsaturated region beneath the soil layer since there is already an extensive body of literature on surface soil microbial communities and process, e.g., Paul and Clark (1989), Metting (1993), Richter and Markowitz, (1995), and Sylvia et al. (1998); whereas the deeper strata of the unsaturated zone have only recently come under scrutiny for their microbiological properties.« less

  6. The Spatial Predilection for Early Esophageal Squamous Cell Neoplasia: A "Hot Zone" for Endoscopic Screening and Surveillance.

    PubMed

    Wang, Wen-Lun; Chang, I-Wei; Chen, Chien-Chuan; Chang, Chi-Yang; Lin, Jaw-Town; Mo, Lein-Ray; Wang, Hsiu-Po; Lee, Ching-Tai

    2016-04-01

    Early esophageal squamous cell neoplasias (ESCNs) are easily missed with conventional white-light endoscopy. This study aimed to assess whether early ESCNs have a spatial predilection and the patterns of recurrence after endoscopic treatment. We analyzed the circumferential and longitudinal location of early ESCNs, as well as their correlations with exposure to carcinogens in a cohort of 162 subjects with 248 early ESCNs; 219 of which were identified by screening and 29 by surveillance endoscopy. The circumferential location was identified using a clock-face orientation, and the longitudinal location was identified according to the distance from the incisor. The most common circumferential and longitudinal distributions of the early ESCNs were found in the 6 to 9 o'clock quadrant (38.5%) and at 26 to 30 cm from the incisor (41.3%), respectively. A total of 163 lesions (75%) were located in the lower hemisphere arc, and 149 (68.4%) were located at 26 to 35 cm from the incisor. One hundred eleven (51%) early ESCNs were centered within the "hot zone" (i.e., lower hemisphere arc of the esophagus at 26 to 35 cm from the incisor), which comprised 20% of the esophageal area. Exposure to alcohol, betel nut, or cigarette was risk factors for the development of early ESCNs in the lower hemisphere. After complete endoscopic treatment, the mean annual incidence of metachronous tumors was 10%. In addition, 43% of the metachronous recurrent neoplasias developed within the "hot zone." Cox regression analysis revealed that the index tumor within the hot zone (hazard ratio [HR]: 3.19; 95% confidence interval [CI]: 1.17-8.68; P = 0.02) and the presence of numerous Lugol-voiding lesions in the esophageal background mucosa were independent predictors for metachronous recurrence (HR: 4.61; 95% CI: 1.36-15.56; P = 0.01). We identified a hot zone that may be used to enhance the detection of early ESCNs during endoscopic screening and surveillance, especially in areas that

  7. Genetically Modified T-cell Infusion Following Peripheral Blood Stem Cell Transplant in Treating Patients With Recurrent or High-Risk Non-Hodgkin Lymphoma

    ClinicalTrials.gov

    2018-01-26

    Adult Grade III Lymphomatoid Granulomatosis; Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Intraocular Lymphoma; Nodal Marginal Zone B-cell Lymphoma; Post-transplant Lymphoproliferative Disorder; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Small Lymphocytic Lymphoma; Refractory Hairy Cell Leukemia; Small Intestine Lymphoma; Splenic Marginal Zone Lymphoma; Testicular Lymphoma; Waldenström Macroglobulinemia

  8. ADAM10 is essential for Notch2-dependent marginal zone B cell development and CD23 cleavage in vivo

    PubMed Central

    Gibb, David R.; El Shikh, Mohey; Kang, Dae-Joong; Rowe, Warren J.; El Sayed, Rania; Cichy, Joanna; Yagita, Hideo; Tew, John G.; Dempsey, Peter J.; Crawford, Howard C.

    2010-01-01

    The proteolytic activity of a disintegrin and metalloproteinase 10 (ADAM10) regulates cell-fate decisions in Drosophila and mouse embryos. However, in utero lethality of ADAM10−/− mice has prevented examination of ADAM10 cleavage events in lymphocytes. To investigate their role in B cell development, we generated B cell–specific ADAM10 knockout mice. Intriguingly, deletion of ADAM10 prevented development of the entire marginal zone B cell (MZB) lineage. Additionally, cleavage of the low affinity IgE receptor, CD23, was profoundly impaired, but subsequent experiments demonstrated that ADAM10 regulates CD23 cleavage and MZB development by independent mechanisms. Development of MZBs is dependent on Notch2 signaling, which requires proteolysis of the Notch2 receptor by a previously unidentified proteinase. Further experiments revealed that Notch2 signaling is severely impaired in ADAM10-null B cells. Thus, ADAM10 critically regulates MZB development by initiating Notch2 signaling. This study identifies ADAM10 as the in vivo CD23 sheddase and an important regulator of B cell development. Moreover, it has important implications for the treatment of numerous CD23- and Notch-mediated pathologies, ranging from allergy to cancer. PMID:20156974

  9. Effect of thrombin preconditioning on migration of subventricular zone-derived cells after intracerebral hemorrhage in rats.

    PubMed

    Guan, Jingxia; Zhang, Shaofeng; Zhou, Qin; Yuan, Zhenhua; Lu, Zuneng

    2016-09-01

    To investigate the effect of thrombin preconditioning (TPC) on the intracerebral hemorrhage (ICH)-induced proliferation, migration, and function of subventriclular zone (SVZ) cells and to find new strategies that enhance endogenous neurogenesis after ICH. Male Sprague-Dawley rats were randomly divided into 3 groups (ICH, TPC, and control group). Rats of each group were randomly divided into 5 subgroups (3-d, 7-d, 14-d, 21-d, and 28-d subgroup). ICH was caused by intrastrial stereotactic administration of collagenase type IV. Brdu was used to label newborn SVZ cells. Organotypic brain slices were cultured to dynamically observe the migration of SVZ cells at living brain tissue. Migration of Dil-labeled SVZ cells in living brain slices was traced by time-lapse microscopy. To assess whether SVZ cells migrating to injured striatum had the ability to form synapses with other cells, brain slices from each group were double immunolabeled with Brdu and synapsin I. The number of Brdu-positive cells markedly increased in the ipsilateral SVZ and striatum 3 days after TPC, peaked at 14 days (P < 0.01), continued to 21 days, and then gradually decreased at 28 days with significant difference compared to the ICH group at each time point (P < 0.01). Migration of Dil-labeled SVZ cells in brain slices in each group was observed and imaged during a 12-h period. Dil-labeled SVZ cells in the TPC group were observed to migrate laterally toward striatum with time with a faster velocity compared to the ICH group (P < 0.01). Our study also demonstrated that TPC induced strong colocalization of Brdu and synapsin I in the ipsilateral striatum between 3 and 28 days after injury.TPC made colocalization of Brdu and synapsin I appear earlier and continue for a longer time compared to the ICH group. Our results demonstrated that TPC could promote proliferation, migration, and function of SVZ cells after ICH, which may provide a new idea for enhancing endogenous neurogenesis and developing

  10. Rainfall Morphology in Semi-Tropical Convergence Zones

    NASA Technical Reports Server (NTRS)

    Shepherd, J. Marshall; Ferrier, Brad S.; Ray, Peter S.

    2000-01-01

    Central Florida is the ideal test laboratory for studying convergence zone-induced convection. The region regularly experiences sea breeze fronts and rainfall-induced outflow boundaries. The focus of this study is the common yet poorly-studied convergence zone established by the interaction of the sea breeze front and an outflow boundary. Previous studies have investigated mechanisms primarily affecting storm initiation by such convergence zones. Few have focused on rainfall morphology yet these storms contribute a significant amount precipitation to the annual rainfall budget. Low-level convergence and mid-tropospheric moisture have both been shown to correlate with rainfall amounts in Florida. Using 2D and 3D numerical simulations, the roles of low-level convergence and mid-tropospheric moisture in rainfall evolution are examined. The results indicate that time-averaged, vertical moisture flux (VMF) at the sea breeze front/outflow convergence zone is directly and linearly proportional to initial condensation rates. This proportionality establishes a similar relationship between VMF and initial rainfall. Vertical moisture flux, which encompasses depth and magnitude of convergence, is better correlated to initial rainfall production than surface moisture convergence. This extends early observational studies which linked rainfall in Florida to surface moisture convergence. The amount and distribution of mid-tropospheric moisture determines how rainfall associated with secondary cells develop. Rainfall amount and efficiency varied significantly over an observable range of relative humidities in the 850- 500 mb layer even though rainfall evolution was similar during the initial or "first-cell" period. Rainfall variability was attributed to drier mid-tropospheric environments inhibiting secondary cell development through entrainment effects. Observationally, 850-500 mb moisture structure exhibits wider variability than lower level moisture, which is virtually always

  11. The Hajdu Cheney Mutation Is a Determinant of B-Cell Allocation of the Splenic Marginal Zone.

    PubMed

    Yu, Jungeun; Zanotti, Stefano; Walia, Bhavita; Jellison, Evan; Sanjay, Archana; Canalis, Ernesto

    2018-01-01

    The neurogenic locus notch homolog protein (Notch)-2 receptor is a determinant of B-cell allocation, and gain-of-NOTCH2-function mutations are associated with Hajdu-Cheney syndrome (HCS), a disease presenting with osteoporosis and acro-osteolysis. We generated a mouse model reproducing the HCS mutation (Notch2HCS), and heterozygous global mutant mice displayed gain-of-Notch2 function. In the mutant spleen, the characteristic perifollicular rim marking the marginal zone (MZ), which is the interface between the nonlymphoid red pulp and the lymphoid white pulp, merged with components of the white pulp. As a consequence, the MZ of Notch2HCS mice occupied most of the splenic structure. To explore the mechanisms involved, lymphocyte populations from the bone marrow and spleen were harvested from heterozygous Notch2HCS mice and sex-matched control littermates and analyzed by flow cytometry. Notch2HCS mice had an increase in CD21/35 high CD23 - splenic MZ B cells of approximately fivefold and a proportional decrease in splenic follicular B cells (CD21/35 int CD23 + ) at 1, 2, and 12 months of age. Western blot analysis revealed that Notch2HCS mutant splenocytes had increased phospho-Akt and phospho-Jun N-terminal kinase, and gene expression analysis of splenic CD19 + B cells demonstrated induction of Hes1 and Hes5 in Notch2HCS mutants. Anti-Notch2 antibodies decreased MZ B cells in control and Notch2HCS mice. In conclusion, Notch2HCS mutant mice have increased mature B cells in the MZ of the spleen. Copyright © 2018 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  12. Brief Report: Robo1 Regulates the Migration of Human Subventricular Zone Neural Progenitor Cells During Development.

    PubMed

    Guerrero-Cazares, Hugo; Lavell, Emily; Chen, Linda; Schiapparelli, Paula; Lara-Velazquez, Montserrat; Capilla-Gonzalez, Vivian; Clements, Anna Christina; Drummond, Gabrielle; Noiman, Liron; Thaler, Katrina; Burke, Anne; Quiñones-Hinojosa, Alfredo

    2017-07-01

    Human neural progenitor cell (NPC) migration within the subventricular zone (SVZ) of the lateral ganglionic eminence is an active process throughout early brain development. The migration of human NPCs from the SVZ to the olfactory bulb during fetal stages resembles what occurs in adult rodents. As the human brain develops during infancy, this migratory stream is drastically reduced in cell number and becomes barely evident in adults. The mechanisms regulating human NPC migration are unknown. The Slit-Robo signaling pathway has been defined as a chemorepulsive cue involved in axon guidance and neuroblast migration in rodents. Slit and Robo proteins expressed in the rodent brain help guide neuroblast migration from the SVZ through the rostral migratory stream to the olfactory bulb. Here, we present the first study on the role that Slit and Robo proteins play in human-derived fetal neural progenitor cell migration (hfNPC). We describe that Robo1 and Robo2 isoforms are expressed in the human fetal SVZ. Furthermore, we demonstrate that Slit2 is able to induce a chemorepellent effect on the migration of hfNPCs derived from the human fetal SVZ. In addition, when Robo1 expression is inhibited, hfNPCs are unable to migrate to the olfactory bulb of mice when injected in the anterior SVZ. Our findings indicate that the migration of human NPCs from the SVZ is partially regulated by the Slit-Robo axis. This pathway could be regulated to direct the migration of NPCs in human endogenous neural cell therapy. Stem Cells 2017;35:1860-1865. © 2017 AlphaMed Press.

  13. Method for preparing a sodium/sulfur cell

    DOEpatents

    Weiner, Steven A.

    1978-01-01

    A method for preparing a sodium/sulfur cell comprising (A) inserting a solid sodium slug, adapted to be connected to an external circuit, into the anodic reaction zone of a cell subassembly maintained within an inert atmosphere, said cell subassembly comprising a cell container and a tubular cation-permeable barrier disposed within said container such that a first reaction zone is located within cation-permeable barrier and a second reaction zone is located between the outer surface of said cation-permeable barrier and the inner surface of said container, one of said reaction zones being said anodic reaction zone and the other of said reaction zone being a cathodic reaction zone containing a precast composite cathodic reactant comprising a sulfur impregnated porous conductive material connected to said cation permeable barrier and adapted to be connected to said external circuit; and (B) providing closure means for said subassembly and sealing the same to said subassembly at a temperature less than about 100.degree. C. The method of the invention overcomes deficiencies of the prior art methods by allowing preparation of a sodium/sulfur cell without the use of molten reactants and the fill spouts which are required when the cell is filled with molten reactants.

  14. Antibody response against Betaferon® in immune tolerant mice: involvement of marginal zone B-cells and CD4+ T-cells and apparent lack of immunological memory.

    PubMed

    Sauerborn, Melody; van Beers, Miranda M C; Jiskoot, Wim; Kijanka, Grzegorz M; Boon, Louis; Schellekens, Huub; Brinks, Vera

    2013-01-01

    The immunological processes underlying immunogenicity of recombinant human therapeutics are poorly understood. Using an immune tolerant mouse model we previously demonstrated that aggregates are a major trigger of the antidrug antibody (ADA) response against recombinant human interferon beta (rhIFNβ) products including Betaferon®, and that immunological memory seems to be lacking after a rechallenge with non-aggregated rhIFNβ. The apparent absence of immunological memory indicates a CD4+ T-cell independent (Tind) immune response underlying ADA formation against Betaferon®. This hypothesis was tested. Using the immune tolerant mouse model we first validated that rechallenge with highly aggregated rhIFNβ (Betaferon®) does not lead to a subsequent fast increase in ADA titers, suggesting a lack of immunological memory. Next we assessed whether Betaferon® could act as Tind antigen by inactivation of marginal zone (MZ) B-cells during treatment. MZ B-cells are major effector cells involved in a Tind immune response. In a following experiment we depleted the mice from CD4+ T-cells to test their involvement in the ADA response against Betaferon®. Inactivation of MZ B-cells at the start of Betaferon® treatment drastically lowered ADA levels, suggesting a Tind immune response. However, persistent depletion of CD4+ T-cells before and during Betaferon® treatment abolished the ADA response in almost all mice. The immune response against rhIFNβ in immune tolerant mice is neither a T-cell independent nor a classical T-cell dependent immune response. Further studies are needed to confirm absence of immunological memory (cells).

  15. Safety Zones

    EPA Pesticide Factsheets

    These are established primarily to reduce the accidental spread of hazardous substances by workers or equipment from contaminated areas to clean areas. They include the exclusion (hot) zone, contamination reduction (warm) zone, and support (cold) zone.

  16. Aging results in copper accumulations in glial fibrillary acidic protein-positive cells in the subventricular zone.

    PubMed

    Pushkar, Yulia; Robison, Gregory; Sullivan, Brendan; Fu, Sherleen X; Kohne, Meghan; Jiang, Wendy; Rohr, Sven; Lai, Barry; Marcus, Matthew A; Zakharova, Taisiya; Zheng, Wei

    2013-10-01

    Analysis of rodent brains with X-ray fluorescence (XRF) microscopy combined with immunohistochemistry allowed us to demonstrate that local Cu concentrations are thousands of times higher in the glia of the subventricular zone (SVZ) than in other cells. Using XRF microscopy with subcellular resolution and intracellular X-ray absorption spectroscopy we determined the copper (I) oxidation state and the sulfur ligand environment. Cu K-edge X-ray absorption near edge spectroscopy is consistent with Cu being bound as a multimetallic Cu-S cluster similar to one present in Cu-metallothionein. Analysis of age-related changes show that Cu content in astrocytes of the SVZ increases fourfold from 3 weeks to 9 months, while Cu concentration in other brain areas remain essentially constant. This increase in Cu correlates with a decrease in adult neurogenesis assessed using the Ki67 marker (both, however, can be age-related effects). We demonstrate that the Cu distribution and age-related concentration changes in the brain are highly cell specific. © 2013 The Anatomical Society and John Wiley & Sons Ltd.

  17. Splenic marginal zone lymphoma: from genetics to management.

    PubMed

    Arcaini, Luca; Rossi, Davide; Paulli, Marco

    2016-04-28

    Splenic marginal zone lymphoma (SMZL) is a rare B-cell malignancy involving the spleen, bone marrow, and frequently the blood. SMZL lymphomagenesis involves antigen and/or superantigen stimulation and molecular deregulation of genes (NOTCH2 and KLF2) involved in the physiological differentiation of spleen marginal zone B cells. Diagnosis requires either spleen histology or, alternatively, the documentation of a typical cell morphology and immunophenotype on blood cells coupled with the detection of intrasinusoidal infiltration by CD20(+) cells in the bone marrow. Among B-cell tumors, deletion of 7q and NOTCH2 mutations are almost specific lesions of SMZL, thus representing promising diagnostic biomarkers of this lymphoma. Although the majority of SMZLs show an indolent course with a median survival of approximately 10 years, nearly 30% of patients experience a poor outcome. No randomized trials are reported for SMZL, and few prospective trials are available. A watch-and-wait approach is advisable for asymptomatic patients. Treatment options for symptomatic patients ranges from splenectomy to rituximab alone or combined with chemotherapy. In some geographic areas, a subset of patients with SMZL associates with hepatitis C virus infection, prompting virus eradication as an effective lymphoma treatment. It would be worthwhile to explore deregulated cellular programs of SMZL as therapeutic targets in the future; improved clinical and biological prognostication will be essential for identifying patients who may benefit from novel approaches. © 2016 by The American Society of Hematology.

  18. Drought Induces Distinct Growth Response, Protection, and Recovery Mechanisms in the Maize Leaf Growth Zone1[OPEN

    PubMed Central

    Avramova, Viktoriya; AbdElgawad, Hamada; Zhang, Zhengfeng; Fotschki, Bartosz; Casadevall, Romina; Vergauwen, Lucia; Knapen, Dries; Taleisnik, Edith; Guisez, Yves; Asard, Han; Beemster, Gerrit T.S.

    2015-01-01

    Drought is the most important crop yield-limiting factor, and detailed knowledge of its impact on plant growth regulation is crucial. The maize (Zea mays) leaf growth zone offers unique possibilities for studying the spatiotemporal regulation of developmental processes by transcriptional analyses and methods that require more material, such as metabolite and enzyme activity measurements. By means of a kinematic analysis, we show that drought inhibits maize leaf growth by inhibiting cell division in the meristem and cell expansion in the elongation zone. Through a microarray study, we observed the down-regulation of 32 of the 54 cell cycle genes, providing a basis for the inhibited cell division. We also found evidence for an up-regulation of the photosynthetic machinery and the antioxidant and redox systems. This was confirmed by increased chlorophyll content in mature cells and increased activity of antioxidant enzymes and metabolite levels across the growth zone, respectively. We demonstrate the functional significance of the identified transcriptional reprogramming by showing that increasing the antioxidant capacity in the proliferation zone, by overexpression of the Arabidopsis (Arabidopsis thaliana) iron-superoxide dismutase gene, increases leaf growth rate by stimulating cell division. We also show that the increased photosynthetic capacity leads to enhanced photosynthesis upon rewatering, facilitating the often-observed growth compensation. PMID:26297138

  19. Stromal Fibroblasts from the Interface Zone of Triple Negative Breast Carcinomas Induced Epithelial-Mesenchymal Transition and its Inhibition by Emodin

    PubMed Central

    Wang, Hao-Yu; Hung, Chao-Ming; Lin, Ying-Chao; Ho, Chi-Tang; Way, Tzong-Der

    2017-01-01

    “Triple negative breast cancer” (TNBC) is associated with a higher rate and earlier time of recurrence and worse prognosis after recurrence. In this study, we aimed to examine the crosstalk between fibroblasts and TNBC cells. The fibroblasts were isolated from TNBC patients’ tissue in tumor burden zones, distal normal zones and interface zones. The fibroblasts were indicated as cancer-associated fibroblasts (CAFs), normal zone fibroblasts (NFs) and interface zone fibroblasts (INFs). Our study found that INFs grew significantly faster than NFs and CAFs in vitro. The epithelial BT20 cells cultured with the conditioned medium of INFs (INFs-CM) and CAFs (CAFs-CM) showed more spindle-like shape and cell scattering than cultured with the conditioned medium of NFs (NFs-CM). These results indicated that factors secreted by INFs-CM or CAFs-CM could induce the epithelial-mesenchymal transition (EMT) phenotype in BT20 cells. Using an in vitro co-culture model, INFs or CAFs induced EMT and promoted cancer cell migration in BT20 cells. Interestingly, we found that emodin inhibited INFs-CM or CAFs-CM-induced EMT programming and phenotype in BT20 cells. Previous studies reported that CAFs and INFs-secreted TGF-β promoted human breast cancer cell proliferation, here; our results indicated that TGF-β initiated EMT in BT20 cells. Pretreatment with emodin significantly suppressed the TGF-β-induced EMT and cell migration in BT20 cells. These results suggest that emodin may be used as a novel agent for the treatment of TNBC. PMID:28060811

  20. Rituximab in Treating Patients Undergoing Donor Peripheral Blood Stem Cell Transplant for Relapsed or Refractory B-cell Lymphoma

    ClinicalTrials.gov

    2017-12-05

    B-cell Adult Acute Lymphoblastic Leukemia; B-cell Childhood Acute Lymphoblastic Leukemia; B-cell Chronic Lymphocytic Leukemia; Childhood Burkitt Lymphoma; Childhood Diffuse Large Cell Lymphoma; Childhood Immunoblastic Large Cell Lymphoma; Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Intraocular Lymphoma; Nodal Marginal Zone B-cell Lymphoma; Post-transplant Lymphoproliferative Disorder; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Childhood Acute Lymphoblastic Leukemia; Recurrent Childhood Grade III Lymphomatoid Granulomatosis; Recurrent Childhood Large Cell Lymphoma; Recurrent Childhood Lymphoblastic Lymphoma; Recurrent Childhood Small Noncleaved Cell Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Small Lymphocytic Lymphoma; Recurrent/Refractory Childhood Hodgkin Lymphoma; Refractory Chronic Lymphocytic Leukemia; Refractory Hairy Cell Leukemia; Small Intestine Lymphoma; Splenic Marginal Zone Lymphoma; Testicular Lymphoma; Waldenström Macroglobulinemia

  1. Differential regulation of cell proliferation in neurogenic zones in mice lacking cystine transport by xCT

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

    Liu, Richard R.; Brown, Craig E.; Brain Research Center, University of British Columbia, Vancouver, BC, V6T 1Z3

    2007-12-21

    The cystine/glutamate exchanger (xCT) supplies intracellular cyst(e)ine for the production of glutathione, a major cellular anti-oxidant. xCT is enriched in brain regions associated with neurogenesis. Previous studies have shown that the malfunction of this protein greatly attenuates cell proliferation in vitro and is associated with brain atrophy in vivo. Using mice that are homozygous for a function-blocking deletion in xCT (Sut mice), we examined in vivo the role of xCT in cell proliferation in neurogenic regions of the subventricular zone (SVZ) and denate gyrus (DG) in the adult brain. Our results indicate that a high level of cellular proliferation inmore » the adult brain persists even in the absence of functional xCT. Furthermore, in both young adult and middle-aged mice (3 and 11 months old), rates of SVZ cell proliferation were comparable between Sut and wild-type controls, although there was trend towards reduced proliferation in Sut mice (12% and 9% reduction, respectively). To our surprise, rates of cell proliferation in the DG were elevated in both 3- and 11-month-old Sut mice relative to controls (22% and 28% increase, respectively). These results demonstrate that xCT expression plays a role in regulating cellular proliferation in the DG, but not the SVZ of adult mice. Furthermore, unlike previous in vitro studies, our in vivo observations clearly indicate that xCT is not essential for ongoing cellular proliferation.« less

  2. 75 FR 30372 - Foreign-Trade Zone 196 Temporary/Interim Manufacturing Authority ATC Logistics & Electronics...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-01

    ... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Docket T-2-2010] Foreign-Trade Zone 196 Temporary/Interim Manufacturing Authority ATC Logistics & Electronics (Cell Phone Kitting and Distribution... filed an application submitted by the ATC Logistics & Electronics, operator of Site 2, FTZ 196...

  3. Neuregulin 1 Type II-ErbB Signaling Promotes Cell Divisions Generating Neurons from Neural Progenitor Cells in the Developing Zebrafish Brain.

    PubMed

    Sato, Tomomi; Sato, Fuminori; Kamezaki, Aosa; Sakaguchi, Kazuya; Tanigome, Ryoma; Kawakami, Koichi; Sehara-Fujisawa, Atsuko

    2015-01-01

    Post-mitotic neurons are generated from neural progenitor cells (NPCs) at the expense of their proliferation. Molecular and cellular mechanisms that regulate neuron production temporally and spatially should impact on the size and shape of the brain. While transcription factors such as neurogenin1 (neurog1) and neurod govern progression of neurogenesis as cell-intrinsic mechanisms, recent studies show regulatory roles of several cell-extrinsic or intercellular signaling molecules including Notch, FGF and Wnt in production of neurons/neural progenitor cells from neural stem cells/radial glial cells (NSCs/RGCs) in the ventricular zone (VZ). However, it remains elusive how production of post-mitotic neurons from neural progenitor cells is regulated in the sub-ventricular zone (SVZ). Here we show that newborn neurons accumulate in the basal-to-apical direction in the optic tectum (OT) of zebrafish embryos. While neural progenitor cells are amplified by mitoses in the apical ventricular zone, neurons are exclusively produced through mitoses of neural progenitor cells in the sub-basal zone, later in the sub-ventricular zone, and accumulate apically onto older neurons. This neurogenesis depends on Neuregulin 1 type II (NRG1-II)-ErbB signaling. Treatment with an ErbB inhibitor, AG1478 impairs mitoses in the sub-ventricular zone of the optic tectum. Removal of AG1478 resumes sub-ventricular mitoses without precedent mitoses in the apical ventricular zone prior to basal-to-apical accumulation of neurons, suggesting critical roles of ErbB signaling in mitoses for post-mitotic neuron production. Knockdown of NRG1-II impairs both mitoses in the sub-basal/sub-ventricular zone and the ventricular zone. Injection of soluble human NRG1 into the developing brain ameliorates neurogenesis of NRG1-II-knockdown embryos, suggesting a conserved role of NRG1 as a cell-extrinsic signal. From these results, we propose that NRG1-ErbB signaling stimulates cell divisions generating neurons from

  4. Fuel conditioning facility zone-to-zone transfer administrative controls.

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

    Pope, C. L.

    2000-06-21

    The administrative controls associated with transferring containers from one criticality hazard control zone to another in the Argonne National Laboratory (ANL) Fuel Conditioning Facility (FCF) are described. FCF, located at the ANL-West site near Idaho Falls, Idaho, is used to remotely process spent sodium bonded metallic fuel for disposition. The process involves nearly forty widely varying material forms and types, over fifty specific use container types, and over thirty distinct zones where work activities occur. During 1999, over five thousand transfers from one zone to another were conducted. Limits are placed on mass, material form and type, and container typesmore » for each zone. Ml material and containers are tracked using the Mass Tracking System (MTG). The MTG uses an Oracle database and numerous applications to manage the database. The database stores information specific to the process, including material composition and mass, container identification number and mass, transfer history, and the operators involved in each transfer. The process is controlled using written procedures which specify the zone, containers, and material involved in a task. Transferring a container from one zone to another is called a zone-to-zone transfer (ZZT). ZZTs consist of four distinct phases, select, request, identify, and completion.« less

  5. Focal high cell density generates a gradient of patterns in self-organizing vascular mesenchymal cells.

    PubMed

    Cheng, Henry; Reddy, Aneela; Sage, Andrew; Lu, Jinxiu; Garfinkel, Alan; Tintut, Yin; Demer, Linda L

    2012-01-01

    In embryogenesis, structural patterns, such as vascular branching, may form via a reaction-diffusion mechanism in which activator and inhibitor morphogens guide cells into periodic aggregates. We previously found that vascular mesenchymal cells (VMCs) spontaneously aggregate into nodular structures and that morphogen pairs regulate the aggregation into patterns of spots and stripes. To test the effect of a focal change in activator morphogen on VMC pattern formation, we created a focal zone of high cell density by plating a second VMC layer within a cloning ring over a confluent monolayer. After 24 h, the ring was removed and pattern formation monitored by phase-contrast microscopy. At days 2-8, the patterns progressed from uniform distributions to swirl, labyrinthine and spot patterns. Within the focal high-density zone (HDZ) and a narrow halo zone, cells aggregated into spot patterns, whilst in the outermost zone of the plate, cells formed a labyrinthine pattern. The area occupied by aggregates was significantly greater in the outermost zone than in the HDZ or halo. The rate of pattern progression within the HDZ increased as a function of its plating density. Thus, focal differences in cell density may drive pattern formation gradients in tissue architecture, such as vascular branching. Copyright © 2012 S. Karger AG, Basel.

  6. Quiescence and activation of stem and precursor cell populations in the subependymal zone of the mammalian brain are associated with distinct cellular and extracellular matrix signals

    USDA-ARS?s Scientific Manuscript database

    The subependymal zone (SEZ) of the lateral ventricles is one of the areas of the adult brain where new neurons are continuously generated from neural stem cells (NSCs), via rapidly dividing precursors. This neurogenic niche is a complex cellular and extracellular microenvironment, highly vascularize...

  7. Zone model predictive control: a strategy to minimize hyper- and hypoglycemic events.

    PubMed

    Grosman, Benyamin; Dassau, Eyal; Zisser, Howard C; Jovanovic, Lois; Doyle, Francis J

    2010-07-01

    Development of an artificial pancreas based on an automatic closed-loop algorithm that uses a subcutaneous insulin pump and continuous glucose sensor is a goal for biomedical engineering research. However, closing the loop for the artificial pancreas still presents many challenges, including model identification and design of a control algorithm that will keep the type 1 diabetes mellitus subject in normoglycemia for the longest duration and under maximal safety considerations. An artificial pancreatic beta-cell based on zone model predictive control (zone-MPC) that is tuned automatically has been evaluated on the University of Virginia/University of Padova Food and Drug Administration-accepted metabolic simulator. Zone-MPC is applied when a fixed set point is not defined and the control variable objective can be expressed as a zone. Because euglycemia is usually defined as a range, zone-MPC is a natural control strategy for the artificial pancreatic beta-cell. Clinical data usually include discrete information about insulin delivery and meals, which can be used to generate personalized models. It is argued that mapping clinical insulin administration and meal history through two different second-order transfer functions improves the identification accuracy of these models. Moreover, using mapped insulin as an additional state in zone-MPC enriches information about past control moves, thereby reducing the probability of overdosing. In this study, zone-MPC is tested in three different modes using unannounced and announced meals at their nominal value and with 40% uncertainty. Ten adult in silico subjects were evaluated following a scenario of mixed meals with 75, 75, and 50 grams of carbohydrates (CHOs) consumed at 7 am, 1 pm, and 8 pm, respectively. Zone-MPC results are compared to those of the "optimal" open-loop preadjusted treatment. Zone-MPC succeeds in maintaining glycemic responses closer to euglycemia compared to the "optimal" open-loop treatment in te three

  8. 33 CFR 165.169 - Safety and Security Zones: New York Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Safety and Security Zones: New York Marine Inspection Zone and Captain of the Port Zone. 165.169 Section 165.169 Navigation and... Areas First Coast Guard District § 165.169 Safety and Security Zones: New York Marine Inspection Zone...

  9. 33 CFR 165.169 - Safety and Security Zones: New York Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Safety and Security Zones: New York Marine Inspection Zone and Captain of the Port Zone. 165.169 Section 165.169 Navigation and... Areas First Coast Guard District § 165.169 Safety and Security Zones: New York Marine Inspection Zone...

  10. 33 CFR 165.169 - Safety and Security Zones: New York Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety and Security Zones: New York Marine Inspection Zone and Captain of the Port Zone. 165.169 Section 165.169 Navigation and... Areas First Coast Guard District § 165.169 Safety and Security Zones: New York Marine Inspection Zone...

  11. 33 CFR 165.169 - Safety and Security Zones: New York Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Safety and Security Zones: New York Marine Inspection Zone and Captain of the Port Zone. 165.169 Section 165.169 Navigation and... Areas First Coast Guard District § 165.169 Safety and Security Zones: New York Marine Inspection Zone...

  12. 33 CFR 165.169 - Safety and Security Zones: New York Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Safety and Security Zones: New York Marine Inspection Zone and Captain of the Port Zone. 165.169 Section 165.169 Navigation and... Areas First Coast Guard District § 165.169 Safety and Security Zones: New York Marine Inspection Zone...

  13. Distribution of electrolytes in cells of the tomato root elongation zone during a gravitropic response

    NASA Astrophysics Data System (ADS)

    Klymchuk, Dmytro

    It is known that gravitropic response of etiolated seedlings is accompanied with asymmetrical distribution of auxins. The higher amount of auxins in the tissues of the lower sides of gravistimulated organs induces cell elongation in shoots and inhibits cell elongation in roots. In spite on the progress in understanding of the auxin-mediated effects on plant growth and development, there is no a complete conception concerning of gravitropic response mechanism. This investigation aims to determine whether the growth response of tomato seedlings on reorientation to the horizontal induces alterations in distribution of electrolytes in cells of the main root elongation zone, the site where induction of the curvature takes place. Tomato (Lycopersicon esculentum, Rio Grande) seedlings were grown on agar surface in 10 cm Petri dishes. The gravitropic response of seedlings was evaluated by the angle of gravitropic curvature after the roots were reoriented 90° from the vertical. Root segments of several mm basipetal to the root tip were fixed in liquid nitrogen, freeze-substituted with Lowicril K11M at -35° C. Sections 100 and 1000 nm thick were cut using LKB Ultrotome V, collected by dry method and analyzed in the 6060 LA SEM at accelerating voltage 15 kV. Using different modes of X-ray microanalysis (X-ray map, - line and -point analysis), distribution of the physiologically relevant ions (Na, P, K, Ca) in cells of surface layers of the upper and lower root sides were investigated. The peculiarities in localization of the electrolytes in different subcellular compartments as well as distribution in the direction between upper and lower sides of the root curvature are discussed.

  14. High Incidence of Preharvest Colonization of Huanglongbing-Symptomatic Citrus sinensis Fruit by Lasiodiplodia theobromae (Diplodia natalensis) and Exacerbation of Postharvest Fruit Decay by That Fungus

    PubMed Central

    Zhao, Wei; Bai, Jinhe; McCollum, Greg

    2014-01-01

    Huanglongbing (HLB), presumably caused by the bacterium “Candidatus Liberibacter asiaticus,” is a devastating citrus disease associated with excessive preharvest fruit drop. Lasiodiplodia theobromae (diplodia) is the causal organism of citrus stem end rot (SER). The pathogen infects citrus fruit under the calyx abscission zone (AZ-C) and is associated with cell wall hydrolytic enzymes similar to plant enzymes involved in abscission. By means of DNA sequencing, diplodia was found in “Ca. Liberibacter asiaticus”-positive juice from HLB-symptomatic fruit (S) but not in “Ca. Liberibacter asiaticus”-negative juice. Therefore, the incidence of diplodia in fruit tissues, the impact on HLB-related postharvest decay, and the implications for HLB-related preharvest fruit drop were investigated in Hamlin and Valencia oranges. Quantitative PCR results (qPCR) revealed a significantly (P < 0.001) greater incidence of diplodia in the AZ-C of HLB-symptomatic (S; “Ca. Liberibacter asiaticus” threshold cycle [CT] of <30) than in the AZ-C of in asymptomatic (AS; “Ca. Liberibacter asiaticus” CT of ≥30) fruit. In agreement with the qPCR results, 2 weeks after exposure to ethylene, the incidences of SER in S fruit were 66.7% (Hamlin) and 58.7% (Valencia), whereas for AS fruit the decay rates were 6.7% (Hamlin) and 5.3% (Valencia). Diplodia colonization of S fruit AZ-C was observed by scanning electron microscopy and confirmed by PCR test and morphology of conidia in isolates from the AZ-C after surface sterilization. Diplodia CT values were negatively correlated with ethylene production (R = −0.838 for Hamlin; R = −0.858 for Valencia) in S fruit, and positively correlated with fruit detachment force (R = 0.855 for Hamlin; R = 0.850 for Valencia), suggesting that diplodia colonization in AZ-C may exacerbate HLB-associated preharvest fruit drop. PMID:25344245

  15. Expression of ACC oxidase promoter-GUS fusions in tomato and Nicotiana plumbaginifolia regulated by developmental and environmental stimuli.

    PubMed

    Blume, B; Grierson, D

    1997-10-01

    The enzyme ACC oxidase, catalysing the last step in the biosynthesis of the plant hormone ethylene, is encoded by a small multigene family in tomato, comprising three members, LEACO1, LEACO2 and LEACO3. LEACO1 is the major gene expressed during ripening, leaf senescence, and wounding (Barry et al., 1996). To investigate the transcriptional regulation of ACC oxidase gene expression, chimeric fusions between the beta-glucuronidase reporter gene and 97 bp of 5' UTR plus 124, 396 and 1825 bp, respectively, of 5' untranscribed LEACO1 sequence were constructed and introduced into Lycopersicon esculentum (Mill cv. Ailsa Craig) and Nicotiana plumbaginifolia. Analysis of transgenic tomatoes indicated that the region containing nucleotides -124 to +97 of the LEACO1 gene is sufficient to confer a marked increase in GUS activity during fruit ripening, albeit at very low levels. Fusion of 396 and 1825 bp of LEACO1 upstream sequence resulted in strong and specific induction of GUS expression in situations known to be accompanied by enhanced ethylene production. Reporter gene expression was similar to that of the endogenous LEACO1 gene, with major increases especially during fruit ripening, senescence and abscission of leaves and, to a lesser extent, of flowers. Analysis of transgenic N. plumbaginifolia plants confirmed the pattern of LEACO1 promoter activity detected in tomato leaves and flowers. Reporter gene expression was also induced following wounding, treatment with ethylene, and pathogen infection. Histochemical analysis illustrated localized GUS activity in the pericarp of ripening fruit, abscission zones of senescent petioles and unfertilized flowers, and at wound sites. These results demonstrate that ACC oxidase is regulated at the transcriptional level in a wide range of cell types at different developmental stages and in response to several external stimuli.

  16. Modulation of flagellum attachment zone protein FLAM3 and regulation of the cell shape in Trypanosoma brucei life cycle transitions

    PubMed Central

    Sunter, Jack D.; Benz, Corinna; Andre, Jane; Whipple, Sarah; McKean, Paul G.; Gull, Keith; Ginger, Michael L.; Lukeš, Julius

    2015-01-01

    ABSTRACT The cell shape of Trypanosoma brucei is influenced by flagellum-to-cell-body attachment through a specialised structure – the flagellum attachment zone (FAZ). T. brucei exhibits numerous morphological forms during its life cycle and, at each stage, the FAZ length varies. We have analysed FLAM3, a large protein that localises to the FAZ region within the old and new flagellum. Ablation of FLAM3 expression causes a reduction in FAZ length; however, this has remarkably different consequences in the tsetse procyclic form versus the mammalian bloodstream form. In procyclic form cells FLAM3 RNAi results in the transition to an epimastigote-like shape, whereas in bloodstream form cells a severe cytokinesis defect associated with flagellum detachment is observed. Moreover, we demonstrate that the amount of FLAM3 and its localisation is dependent on ClpGM6 expression and vice versa. This evidence demonstrates that FAZ is a key regulator of trypanosome shape, with experimental perturbations being life cycle form dependent. An evolutionary cell biology explanation suggests that these differences are a reflection of the division process, the cytoskeleton and intrinsic structural plasticity of particular life cycle forms. PMID:26148511

  17. Single-Cell RNA Sequencing of Lymph Node Stromal Cells Reveals Niche-Associated Heterogeneity.

    PubMed

    Rodda, Lauren B; Lu, Erick; Bennett, Mariko L; Sokol, Caroline L; Wang, Xiaoming; Luther, Sanjiv A; Barres, Ben A; Luster, Andrew D; Ye, Chun Jimmie; Cyster, Jason G

    2018-05-15

    Stromal cells (SCs) establish the compartmentalization of lymphoid tissues critical to the immune response. However, the full diversity of lymph node (LN) SCs remains undefined. Using droplet-based single-cell RNA sequencing, we identified nine peripheral LN non-endothelial SC clusters. Included are the established subsets, Ccl19 hi T-zone reticular cells (TRCs), marginal reticular cells, follicular dendritic cells (FDCs), and perivascular cells. We also identified Ccl19 lo TRCs, likely including cholesterol-25-hydroxylase + cells located at the T-zone perimeter, Cxcl9 + TRCs in the T-zone and interfollicular region, CD34 + SCs in the capsule and medullary vessel adventitia, indolethylamine N-methyltransferase + SCs in the medullary cords, and Nr4a1 + SCs in several niches. These data help define how transcriptionally distinct LN SCs support niche-restricted immune functions and provide evidence that many SCs are in an activated state. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. The memory of the accreting plate boundary and the continuity of fracture zones

    USGS Publications Warehouse

    Schouten, Hans; Klitgord, Kim D.

    1982-01-01

    A detailed aeromagnetic anomaly map of the Mesozoic seafloor-spreading lineations southwest of Bermuda reveals the dominant magnetic grain of the oceanic crust and the character of the accreting boundary at the time of crustal formation. The magnetic anomaly pattern is that of a series of elongate lobes perpendicular to the fracture zone (flowline) trends. The linear sets of magnetic anomaly peaks and troughs have narrow regions of reduced amplitude anomalies associated with the fracture zones. During the period of Mesozoic geomagnetic polarity reversals (when 1200 km of central North Atlantic seafloor formed), the Atlantic accreting boundary consisted of stationary, elongate, spreading center cells that maintained their independence even though sometimes only minor spatial offsets existed between cells. Normal oceanic crustal structure was formed in the spreading center cells, but structural anomalies and discontinuities characteristic of fracture zones were formed at their boundaries, which parallel flowlines of Mesozoic relative plate motion in the central North Atlantic. We suggest that the memory for a stationary pattern of independent spreading center cells resides in the young brittle lithosphere at the accreting boundary where the lithosphere is weakest; here, each spreading center cell independently goes through its cylce of stress buildup, stress release, and crustal accretion, after which its memory is refreshed. The temporal offset between the peaks of the accretionary activity that takes place within each cell may provide the mechanism for maintaining the independence of adjacent spreading center cells through times when no spatial offset between the cells exists.

  19. 78 FR 68814 - Foreign-Trade Zone 32-Miami, Florida, Authorization of Production Activity, Brightstar...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-15

    ... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [B-68-2013] Foreign-Trade Zone 32--Miami, Florida, Authorization of Production Activity, Brightstar Corporation (Cell Phone Kitting), Miami, Florida On June 26, 2013, The Greater Miami Chamber of Commerce, grantee of FTZ 32, submitted a notification of proposed...

  20. Fluctuations in Blood Marginal Zone B-Cell Frequencies May Reflect Migratory Patterns Associated with HIV-1 Disease Progression Status

    PubMed Central

    Poudrier, Johanne; Roger, Michel

    2016-01-01

    We have previously shown that overexpression of BLyS/BAFF was associated with increased relative frequencies of innate “precursor” marginal zone (MZ)-like B-cells in the blood of HIV-1-infected rapid and classic progressors. However, along with relatively normal BLyS/BAFF expression levels, these cells remain unaltered in elite-controllers (EC), rather, percentages of more mature MZ-like B-cells are decreased in the blood of these individuals. Fluctuations in frequencies of blood MZ-like B-cell populations may reflect migratory patterns associated with disease progression status, suggesting an important role for these cells in HIV-1 pathogenesis. We have therefore longitudinally measured plasma levels of B-tropic chemokines by ELISA-based technology as well as their ligands by flow-cytometry on blood B-cell populations of HIV-1-infected individuals with different rates of disease progression and uninfected controls. Migration potential of B-cell populations from these individuals were determined by chemotaxis assays. We found important modulations of CXCL13-CXCR5, CXCL12-CXCR4/CXCR7, CCL20-CCR6 and CCL25-CCR9 chemokine-axes and increased cell migration patterns in HIV progressors. Interestingly, frequencies of CCR6 expressing cells were significantly elevated within the precursor MZ-like population, consistent with increased migration in response to CCL20. Although we found little modulation of chemokine-axes in EC, cell migration was greater than that observed for uninfected controls, especially for MZ-like B-cells. Overall the immune response against HIV-1 may involve recruitment of MZ-like B-cells to peripheral sites. Moreover, our findings suggest that “regulated” attraction of these cells in a preserved BLyS/BAFF non-inflammatory environment, such as encountered in EC could be beneficial to the battle and even control of HIV. PMID:27203285

  1. The structure of melting mushy zones, with implications for Earth's inner core (Invited)

    NASA Astrophysics Data System (ADS)

    Bergman, M. I.; Huguet, L.; Alboussiere, T.

    2013-12-01

    Seismologists have inferred hemispherical differences in the isotropic wavespeed, the elastic anisotropy, the attenuation, and the attenuation anisotropy of Earth's inner core. One hypothesis for these hemispherical differences involves an east-west translation of the inner core, with enhanced solidification on one side and melting on the other. Another hypothesis is that long term mantle control over outer core convection can lead to hemispherical variations in solidification that could even result in melting in some regions of the inner core boundary. It has also been hypothesized that the inner core is growing dendritically, resulting in an inner core that has the structure of a mushy zone (albeit one with a high solid fraction). It would therefore be helpful to understand how the structure of a melting mushy zone might look in comparison with one that is solidifying, in an effort to help interpret the seismic inferences. We have carried out experiments on the solidification of ammonium chloride from an aqueous solution, yielding a mushy zone. The experiments run in a centrifuge, in order to reach a more realistic ratio of convective velocity to phase change rate, expected to be very large at the boundary of the inner core. Hypergravity thus increases the experimental solid fraction of the mush. So far the maximum gravity we have achieved is 200 g. A Peltier cell provides cooling at one end of the cell, and after the mushy zone has grown we turn on a heater at the other end. Probes monitor the temperature along the height of the cell. As ammonium chloride in the mushy zone melts it produces more dense fluid, which results in convection in the mushy zone, a greater ammonium chloride concentration deeper in the mushy zone, and hence enhanced solidification there. This thus changes the solid fraction profile from that during solidification, which may be observable in the lab experiments using ultrasonic transducers and post-mortem under a microscope. The melting

  2. WorkZoneQ user guide for two-lane freeway work zones.

    DOT National Transportation Integrated Search

    2013-06-01

    WorkZoneQ was developed in Visual Basic for Applications (VBA) to implement the results of the previous study, : Queue and Users Costs in Highway Work Zones. This report contains the WorkZoneQ user guide. WorkZoneQ : consists of eight Excel ...

  3. 75 FR 13484 - Foreign-Trade Zone 22; Temporary/Interim Manufacturing Authority; LG Electronics Mobilecomm USA...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-22

    ... DEPARTMENT OF COMMERCE [Docket T-1-2010] Foreign-Trade Zones Board Foreign-Trade Zone 22; Temporary/Interim Manufacturing Authority; LG Electronics Mobilecomm USA, Inc. (Cell Phones); Notice of.../ interim manufacturing (T/IM) authority, on behalf of LG Electronics Mobilecomm USA, Inc. (LGEMU), to...

  4. Molecular differences in transition zone and peripheral zone prostate tumors

    PubMed Central

    Sinnott, Jennifer A.; Rider, Jennifer R.; Carlsson, Jessica; Gerke, Travis; Tyekucheva, Svitlana; Penney, Kathryn L.; Sesso, Howard D.; Loda, Massimo; Fall, Katja; Stampfer, Meir J.; Mucci, Lorelei A.; Pawitan, Yudi; Andersson, Sven-Olof; Andrén, Ove

    2015-01-01

    Prostate tumors arise primarily in the peripheral zone (PZ) of the prostate, but 20–30% arise in the transition zone (TZ). Zone of origin may have prognostic value or reflect distinct molecular subtypes; however, it can be difficult to determine in practice. Using whole-genome gene expression, we built a signature of zone using normal tissue from five individuals and found that it successfully classified nine tumors of known zone. Hypothesizing that this signature captures tumor zone of origin, we assessed its relationship with clinical factors among 369 tumors of unknown zone from radical prostatectomies (RPs) and found that tumors that molecularly resembled TZ tumors showed lower mortality (P = 0.09) that was explained by lower Gleason scores (P = 0.009). We further applied the signature to an earlier study of 88 RP and 333 transurethral resection of the prostate (TURP) tumor samples, also of unknown zone, with gene expression on ~6000 genes. We had observed previously substantial expression differences between RP and TURP specimens, and hypothesized that this might be because RPs capture primarily PZ tumors, whereas TURPs capture more TZ tumors. Our signature distinguished these two groups, with an area under the receiver operating characteristic curve of 87% (P < 0.0001). Our findings that zonal differences in normal tissue persist in tumor tissue and that these differences are associated with Gleason score and sample type suggest that subtypes potentially resulting from different etiologic pathways might arise in these zones. Zone of origin may be important to consider in prostate tumor biomarker research. PMID:25870172

  5. Adult Mouse Subventricular Zone Stem and Progenitor Cells Are Sessile and Epidermal Growth Factor Receptor Negatively Regulates Neuroblast Migration

    PubMed Central

    Kim, Yongsoo; Comte, Isabelle; Szabo, Gabor; Hockberger, Philip; Szele, Francis G.

    2009-01-01

    Background The adult subventricular zone (SVZ) contains stem and progenitor cells that generate neuroblasts throughout life. Although it is well accepted that SVZ neuroblasts are migratory, recent evidence suggests their progenitor cells may also exhibit motility. Since stem and progenitor cells are proliferative and multipotential, if they were also able to move would have important implications for SVZ neurogenesis and its potential for repair. Methodology/Principal Findings We studied whether SVZ stem and/or progenitor cells are motile in transgenic GFP+ slices with two photon time lapse microscopy and post hoc immunohistochemistry. We found that stem and progenitor cells; mGFAP-GFP+ cells, bright nestin-GFP+ cells and Mash1+ cells were stationary in the SVZ and rostral migratory stream (RMS). In our search for motile progenitor cells, we uncovered a population of motile βIII-tubulin+ neuroblasts that expressed low levels of epidermal growth factor receptor (EGFr). This was intriguing since EGFr drives proliferation in the SVZ and affects migration in other systems. Thus we examined the potential role of EGFr in modulating SVZ migration. Interestingly, EGFrlow neuroblasts moved slower and in more tortuous patterns than EGFr-negative neuroblasts. We next questioned whether EGFr stimulation affects SVZ cell migration by imaging Gad65-GFP+ neuroblasts in the presence of transforming growth factor alpha (TGF-α), an EGFr-selective agonist. Indeed, acute exposure to TGF-α decreased the percentage of motile cells by approximately 40%. Conclusions/Significance In summary, the present study directly shows that SVZ stem and progenitor cells are static, that EGFr is retained on some neuroblasts, and that EGFr stimulation negatively regulates migration. This result suggests an additional role for EGFr signaling in the SVZ. PMID:19956583

  6. 76 FR 63202 - Security Zones; Captain of the Port Lake Michigan Zone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-12

    ...-AA87 Security Zones; Captain of the Port Lake Michigan Zone AGENCY: Coast Guard, DHS. ACTION: Final rule. SUMMARY: Based on a review of safety and security zones around critical infrastructure in the... Chicago Harbor & Burnham Park Harbor--Safety and Security Zone regulation and the Security Zones; Captain...

  7. Mapping air quality zones for coastal urban centers.

    PubMed

    Freeman, Brian; Gharabaghi, Bahram; Thé, Jesse; Munshed, Mohammad; Faisal, Shah; Abdullah, Meshal; Al Aseed, Athari

    2017-05-01

    This study presents a new method that incorporates modern air dispersion models allowing local terrain and land-sea breeze effects to be considered along with political and natural boundaries for more accurate mapping of air quality zones (AQZs) for coastal urban centers. This method uses local coastal wind patterns and key urban air pollution sources in each zone to more accurately calculate air pollutant concentration statistics. The new approach distributes virtual air pollution sources within each small grid cell of an area of interest and analyzes a puff dispersion model for a full year's worth of 1-hr prognostic weather data. The difference of wind patterns in coastal and inland areas creates significantly different skewness (S) and kurtosis (K) statistics for the annually averaged pollutant concentrations at ground level receptor points for each grid cell. Plotting the S-K data highlights grouping of sources predominantly impacted by coastal winds versus inland winds. The application of the new method is demonstrated through a case study for the nation of Kuwait by developing new AQZs to support local air management programs. The zone boundaries established by the S-K method were validated by comparing MM5 and WRF prognostic meteorological weather data used in the air dispersion modeling, a support vector machine classifier was trained to compare results with the graphical classification method, and final zones were compared with data collected from Earth observation satellites to confirm locations of high-exposure-risk areas. The resulting AQZs are more accurate and support efficient management strategies for air quality compliance targets effected by local coastal microclimates. A novel method to determine air quality zones in coastal urban areas is introduced using skewness (S) and kurtosis (K) statistics calculated from grid concentrations results of air dispersion models. The method identifies land-sea breeze effects that can be used to manage local air

  8. 33 CFR 165.911 - Security Zones; Captain of the Port Buffalo Zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Security Zones; Captain of the Port Buffalo Zone. 165.911 Section 165.911 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Security Zones; Captain of the Port Buffalo Zone. (a) Location. The following are security zones: (1) Nine...

  9. 33 CFR 165.911 - Security Zones; Captain of the Port Buffalo Zone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Security Zones; Captain of the Port Buffalo Zone. 165.911 Section 165.911 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Security Zones; Captain of the Port Buffalo Zone. (a) Location. The following are security zones: (1) Nine...

  10. 33 CFR 165.911 - Security Zones; Captain of the Port Buffalo Zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Security Zones; Captain of the Port Buffalo Zone. 165.911 Section 165.911 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Security Zones; Captain of the Port Buffalo Zone. (a) Location. The following are security zones: (1) Nine...

  11. 33 CFR 165.911 - Security Zones; Captain of the Port Buffalo Zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Security Zones; Captain of the Port Buffalo Zone. 165.911 Section 165.911 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Security Zones; Captain of the Port Buffalo Zone. (a) Location. The following are security zones: (1) Nine...

  12. 75 FR 4343 - Foreign-Trade Zone 22-Chicago, IL; Application for Manufacturing Authority; LG Electronics...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-27

    ... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Docket 3-2010] Foreign-Trade Zone 22--Chicago, IL; Application for Manufacturing Authority; LG Electronics MobileComm USA, Inc. (Cell Phone Kitting... authority on behalf of LG Electronics MobileComm USA, Inc. (LGEMU), located in Bolingbrook, Illinois. The...

  13. 75 FR 17691 - Foreign-Trade Zone 196 - Fort Worth, Texas, Application for Manufacturing Authority, ATC...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-07

    ... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Docket 19-2010] Foreign-Trade Zone 196 - Fort Worth, Texas, Application for Manufacturing Authority, ATC Logistics & Electronics (Cell Phone Kitting... Board (the Board) by ATC Logistics & Electronics (ATCLE), operator of Site 2, FTZ 196, Fort Worth, Texas...

  14. Electrical signaling, stomatal conductance, ABA and Ethylene content in avocado trees in response to root hypoxia

    PubMed Central

    Gurovich, Luis; Schaffer, Bruce; García, Nicolás; Iturriaga, Rodrigo

    2009-01-01

    Avocado (Persea americana Mill.) trees are among the most sensitive of fruit tree species to root hypoxia as a result of flooded or poorly drained soil. Similar to drought stress, an early physiological response to root hypoxia in avocado is a reduction of stomatal conductance. It has been previously determined in avocado trees that an extracellular electrical signal between the base of stem and leaves is produced and related to reductions in stomatal conductance in response to drought stress. The current study was designed to determine if changes in the extracellular electrical potential between the base of the stem and leaves in avocado trees could also be detected in response to short-term (min) or long-term (days) root hypoxia, and if these signals could be related to stomatal conductance (gs), root and leaf ABA and ACC concentrations, ethylene emission from leaves and leaf abscission. In contrast to previous observations for drought-stressed trees, short-term or long-term root hypoxia did not stimulate an electrical potential difference between the base of the stem and leaves. Short-term hypoxia did not result in a significant decrease in gs compared with plants in the control treatment, and no differences in ABA concentration were found between plants subjected to hypoxia and control plants. Long-term hypoxia in the root zone resulted in a significant decrease in gs, increased leaf ethylene and increased leaf abscission. The results indicate that for avocado trees exposed to root hypoxia, electrical signals do not appear to be the primary root-to-shoot communication mechanism involved in signaling for stomatal closure as a result of hypoxia in the root zone. PMID:19649181

  15. Molecular Mechanism of Active Zone Organization at Vertebrate Neuromuscular Junctions

    PubMed Central

    Nishimune, Hiroshi

    2013-01-01

    Organization of presynaptic active zones is essential for development, plasticity, and pathology of the nervous system. Recent studies indicate a trans-synaptic molecular mechanism that organizes the active zones by connecting the pre- and the postsynaptic specialization. The presynaptic component of this trans-synaptic mechanism is comprised of cytosolic active zone proteins bound to the cytosolic domains of voltage-dependent calcium channels (P/Q-, N-, and L-type) on the presynaptic membrane. The postsynaptic component of this mechanism is the synapse organizer (laminin β2) that is expressed by the postsynaptic cell and accumulates specifically on top of the postsynaptic specialization. The pre- and the postsynaptic components interact directly between the extracellular domains of calcium channels and laminin β2 to anchor the presynaptic protein complex in front of the postsynaptic specialization. Hence, the presynaptic calcium channel functions as a scaffolding protein for active zone organization and as an ion-conducting channel for synaptic transmission. In contrast to the requirement of calcium influx for synaptic transmission, the formation of the active zone does not require the calcium influx through the calcium channels. Importantly, the active zones of adult synapses are not stable structures and require maintenance for their integrity. Furthermore, aging or diseases of the central and peripheral nervous system impair the active zones. This review will focus on the molecular mechanisms that organize the presynaptic active zones and summarize recent findings at the neuromuscular junctions and other synapses. PMID:22135013

  16. Lymphatic Muscle Cells in Rat Mesenteric Lymphatic Vessels of Various Ages

    PubMed Central

    Bridenbaugh, Eric A.; Nizamutdinova, Irina Tsoy; Jupiter, Daniel; Nagai, Takashi; Thangaswamy, Sangeetha; Chatterjee, Victor

    2013-01-01

    Abstract Background Recent studies on aging-associated changes in mesenteric lymph flow in situ demonstrated predominance of the severe negative chronotropic effect of aging on the contractility of aged mesenteric lymphatic vessels (MLV). At the same time, contraction amplitude of the aged vessels was only slightly diminished by aging and can be rapidly stimulated within 5–15 minutes. However, the detailed quantitative evaluation of potential aging-associated changes in muscle cells investiture in MLV has never been performed. Methods and Results In this study we, for the first time, performed detailed evaluation of muscle cells investiture in MLV in reference to the position of lymphatic valve in different zones of lymphangion within various age groups (3-mo, 9-mo and 24-mo Fischer-344 rats). Using visual and quantitative analyses of the images of MLV immunohistochemically labeled for actin, we confirmed that the zones located close upstream (pre-valve zones) and above lymphatic valves (valve zones) possess the lowest investiture of lymphatic muscle cells. Most of the high muscle cells investiture zones exist downstream to the lymphatic valve (post-valve zones). The muscle cells investiture of these zones is not affected by aging, while pre-valve and valve zones demonstrate significant aging-associated decrease in muscle cells investiture. Conclusions The low muscle cells investiture zones in lymphatic vessels consist of predominantly longitudinally oriented muscle cells which are positioned in pre-valve and valve zones and connect adjacent lymphangions. These cells may provide important functional impact on the biomechanics of the lymphatic valve gating and electrical coupling between lymphangions, while their aging-associated changes may delimit adaptive reserves of aged lymphatic vessels. PMID:23531183

  17. 77 FR 50929 - Security Zones; 2012 RNC Bridge Security Zones, Captain of the Port St. Petersburg Zone, Tampa, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-23

    ...-AA87 Security Zones; 2012 RNC Bridge Security Zones, Captain of the Port St. Petersburg Zone, Tampa, FL... temporary security zones around certain bridges on the waters of Pinellas County and Tampa Bay, Florida..., or mooring on waters within 50 yards of the designated bridges during the times that the security...

  18. Direct methanol fuel cell with extended reaction zone anode: PtRu and PtRuMo supported on graphite felt

    NASA Astrophysics Data System (ADS)

    Bauer, Alex; Gyenge, Előd L.; Oloman, Colin W.

    Pressed graphite felt (thickness ∼350 μm) with electrodeposited PtRu (43 g m -2, 1.4:1 atomic ratio) or PtRuMo (52 g m -2, 1:1:0.3 atomic ratio) nanoparticle catalysts was investigated as an anode for direct methanol fuel cells. At temperatures above 333 K the fuel cell performance of the PtRuMo catalyst was superior compared to PtRu. The power density was 2200 W m -2 with PtRuMo at 5500 A m -2 and 353 K while under the same conditions PtRu yielded 1925 W m -2. However, the degradation rate of the Mo containing catalyst formulation was higher. Compared to conventional gas diffusion electrodes with comparable PtRu catalyst composition and load, the graphite felt anodes gave higher power densities mainly due to the extended reaction zone for methanol oxidation.

  19. Slip Zone versus Damage Zone Micromechanics, Arima-Takasuki Tectonic Line, Japan

    NASA Astrophysics Data System (ADS)

    White, J. C.; Lin, A.

    2017-12-01

    The Arima-Takasuki Tectonic Line (ATTL) of southern Honshu, Japan is defined by historically active faults and multiple splays producing M7 earthquakes. The damage zone of the ATTL comprises a broad zone of crushed, comminuted and pulverized granite/rhyolite1,2containing cm-scale slip zones and highly comminuted injection veins. In this presentation, prior work on the ATTL fault rocks is extending to include microstructural characterization by transmission electron microscopy (TEM) from recent trenching of the primary slip zone, as well as secondary slip zones. This is necessary to adequately characterize the extremely fine-grained material (typically less than 1mm) in both damage and core zones. Damage zone material exhibits generally random textures3 whereas slip zones are macroscopically foliated, and compositionally layered, notwithstanding a fairly homogeneous protolith. The latter reflects fluid-rock interaction during both coseismic and interseismic periods. The slip zones are microstructurally heterogeneous at all scales, comprising not only cataclasites and phyllosilicate (clay)-rich gouge zones, but Fe/Mn pellets or clasts that are contained within gouge. These structures appear to have rolled and would suggest rapid recrystallization and/or growth. A central question related to earthquake recurrence along existing faults is the nature of the gouge. In both near-surface exposures and ongoing drilling at depth, "plastic" or "viscous" gouge zones comprise ultra-fine-grained clay-siliciclastic particles that would not necessarily respond in a simple frictional manner. Depending on whether the plastic nature of these slip zones develops during or after slip, subsequent focusing of slip within them could be complicated. 1 Mitchell, T.A., Ben-Zion, Y., Shimamoto, T., 2011. Ear. Planet. Sci. Lett. 308, 284-297. 2 Lin, A., Yamashita, K, Tanaka, M. J., 2013. Struc. Geol. 48, 3-13. 3 White, J.C., Lin, A. 2016. Proc. AGU Fall Mtg., T42-02 San Francisco.

  20. Bortezomib and Filgrastim in Promoting Stem Cell Mobilization in Patients With Non-Hodgkin Lymphoma or Multiple Myeloma Undergoing Stem Cell Transplant

    ClinicalTrials.gov

    2017-05-23

    Adult Grade III Lymphomatoid Granulomatosis; B-cell Chronic Lymphocytic Leukemia; Contiguous Stage II Adult Burkitt Lymphoma; Contiguous Stage II Adult Diffuse Large Cell Lymphoma; Contiguous Stage II Adult Diffuse Mixed Cell Lymphoma; Contiguous Stage II Adult Diffuse Small Cleaved Cell Lymphoma; Contiguous Stage II Adult Immunoblastic Large Cell Lymphoma; Contiguous Stage II Adult Lymphoblastic Lymphoma; Contiguous Stage II Grade 1 Follicular Lymphoma; Contiguous Stage II Grade 2 Follicular Lymphoma; Contiguous Stage II Grade 3 Follicular Lymphoma; Contiguous Stage II Mantle Cell Lymphoma; Contiguous Stage II Marginal Zone Lymphoma; Contiguous Stage II Small Lymphocytic Lymphoma; Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Intraocular Lymphoma; Nodal Marginal Zone B-cell Lymphoma; Noncontiguous Stage II Adult Burkitt Lymphoma; Noncontiguous Stage II Adult Diffuse Large Cell Lymphoma; Noncontiguous Stage II Adult Diffuse Mixed Cell Lymphoma; Noncontiguous Stage II Adult Diffuse Small Cleaved Cell Lymphoma; Noncontiguous Stage II Adult Immunoblastic Large Cell Lymphoma; Noncontiguous Stage II Adult Lymphoblastic Lymphoma; Noncontiguous Stage II Grade 1 Follicular Lymphoma; Noncontiguous Stage II Grade 2 Follicular Lymphoma; Noncontiguous Stage II Grade 3 Follicular Lymphoma; Noncontiguous Stage II Mantle Cell Lymphoma; Noncontiguous Stage II Marginal Zone Lymphoma; Noncontiguous Stage II Small Lymphocytic Lymphoma; Progressive Hairy Cell Leukemia, Initial Treatment; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular

  1. Evaluation of Ohio work zone speed zones process.

    DOT National Transportation Integrated Search

    2014-06-01

    This report describes the methodology and results of analyses performed to determine the effectiveness of Ohio Department of Transportation processes for establishing work zone speed zones. Researchers observed motorists speed choice upstream of a...

  2. Controlled field study on the use of nitrate and oxygen for bioremediation of a gasoline source zone

    USGS Publications Warehouse

    Barbaro, J.R.; Barker, J.F.

    2000-01-01

    Controlled releases of unleaded gasoline were utilized to evaluate the biotransformation of the soluble aromatic hydrocarbons (benzene, toluene, ethylbenzene, xylene isomers, trimethylbenzene isomers, and naphthalene) within a source zone using nitrate and oxygen as electron acceptors. Experiments were conducted within two 2 m ?? 2 m ?? 3.5 m deep sheet-piling cells. In each treatment cell, a gasoline-contaminated zone was created below the water table. Groundwater amended with electron acceptors was then flushed continuously through the cells for 174 day. Electron-acceptor utilization and hydrocarbon-metabolite formation were noted in both cells, indicating that some microbial activity had been induced in response to flushing. Relative to the cell residence time, nitrate utilization was slow and aromatic-hydrocarbon mass losses in response to microaerophilic dissolved oxygen addition were not obvious under these in situ conditions. There was relatively little biotransformation of the aromatic hydrocarbons over the 2-m flow path monitored in this experiment. A large denitrifying population capable of aromatic hydrocarbon biotransformation failed to develop within the gasoline source zone over a 14-mo period of nitrate exposure.

  3. Alisertib in Combination With Vorinostat in Treating Patients With Relapsed or Recurrent Hodgkin Lymphoma, B-Cell Non-Hodgkin Lymphoma, or Peripheral T-Cell Lymphoma

    ClinicalTrials.gov

    2018-04-10

    Adult B Acute Lymphoblastic Leukemia; Adult T Acute Lymphoblastic Leukemia; Anaplastic Large Cell Lymphoma; Angioimmunoblastic T-Cell Lymphoma; Chronic Lymphocytic Leukemia; Extranodal Marginal Zone Lymphoma of Mucosa-Associated Lymphoid Tissue; Hepatosplenic T-Cell Lymphoma; Intraocular Lymphoma; Lymphomatous Involvement of Non-Cutaneous Extranodal Site; Mature T-Cell and NK-Cell Non-Hodgkin Lymphoma; Nodal Marginal Zone Lymphoma; Primary Cutaneous B-Cell Non-Hodgkin Lymphoma; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Adult T-Cell Leukemia/Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Mycosis Fungoides and Sezary Syndrome; Recurrent Non-Hodgkin Lymphoma; Recurrent Primary Cutaneous T-Cell Non-Hodgkin Lymphoma; Recurrent Small Lymphocytic Lymphoma; Refractory Chronic Lymphocytic Leukemia; Refractory Hairy Cell Leukemia; Small Intestinal Lymphoma; Splenic Marginal Zone Lymphoma; T-Cell Large Granular Lymphocyte Leukemia; Testicular Lymphoma; Waldenstrom Macroglobulinemia

  4. Prognostic significance of S-phase fractions in peritumoral invading zone analyzed by laser scanning cytometry in patients with high-grade glioma: A preliminary study.

    PubMed

    Nakajima, Syoichi; Morii, Ken; Takahashi, Hitoshi; Fujii, Yukihiko; Yamanaka, Ryuya

    2016-03-01

    The predominant characteristic of malignant glioma is the presence of invading tumor cells in the peritumoral zone. Distinguishing between tumor cells and normal cells in a peritumoral lesion is challenging. Therefore, the aim of the present study was to investigate the cell-cycle phase measurements of fixed paraffin-embedded specimens from the peritumoral invading zone of high-grade gliomas using laser scanning cytometry. A total of 12 high-grade gliomas (2 anaplastic astrocytomas and 10 glioblastomas) were studied. The tumor core and peritumoral invading zone of each tumor specimen were investigated. Tissue sections (50 µm) from the paraffin blocks were deparaffinized, rehydrated and enzymatically disintegrated, and the cells in suspension were stained with propidium iodide and placed on microscope slides. A slight trend for an increased S-phase fraction in the peritumoral invading zone compared with the tumor core was observed (P=0.24). Additionally, there was a trend for a decrease in the overall survival time of patients with increasing peritumoral invading zone S-phase fraction (P=0.12). These data suggest that laser scanning cytometry is a powerful and clinically relevant tool for the objective analysis of the cell cycle in malignant gliomas.

  5. Upregulation of autophagy and glycolysis markers in keloid hypoxic-zone fibroblasts: Morphological characteristics and implications.

    PubMed

    Ryoko, Okuno; Ito, Yuko; Eid, Nabil; Otsuki, Yoshinori; Kondo, Yoichi; Ueda, Koichi

    2018-05-29

    Keloid is a fibro-proliferative skin disorder with tumor-like behavior and dependence on anaerobic glycolysis (the Warburg effect), but its exact pathogenesis is unknown. Although autophagy is widely accepted as a lysosomal pathway for cell survival and cellular homeostasis (specifically upon exposure to stressors such as hypoxia), very few studies have investigated the involvement of autophagy and related glycolytic effectors in keloidogenesis. Here the authors examined the expression and cellular localization of autophagy proteins (LC3, pan-cathepsin), glycolytic markers (LDH, MCT1, MCT4) and the transcription factor HIF isoforms in human keloid samples using immunohistochemical analysis and double-labeling immunofluorescence methods. Based on H&E staining and expression of CD31, keloids were compartmentalized into hypoxic central and normoxic marginal zones. Vimentin-expressing fibroblasts in the central zone exhibited greater autophagy than their marginal-zone counterparts, as evidenced by increased LC3 puncta formation and co-localization with lysosomal pan-cathepsin. LDH (a lactate stimulator), MCT4 (a lactate exporter) and HIF-1 α expression levels were also higher in central-zone fibroblasts. Conversely, HIF-2 α expression was upregulated in fibroblasts and endothelial cells of the peripheral zone, while MCT1 was expressed in both zones. Taken together, these observations suggest that upregulation of autophagy and glycolysis markers in keloid hypoxic-zone fibroblasts may indicate a prosurvival mechanism allowing the extrusion of lactate to marginal-zone fibroblasts via metabolic coupling. The authors believe this is the first report on differential expression of autophagic and glycolytic markers in keloid-zone fibroblasts. The study results indicate that autophagy inhibitors and MCT4 blockers may have therapeutic implications in keloid treatment.

  6. New genes and new biological roles for expansins

    NASA Technical Reports Server (NTRS)

    Cosgrove, D. J.

    2000-01-01

    Expansins are extracellular proteins that loosen plant cell walls in novel ways. They are thought to function in cell enlargement, pollen tube invasion of the stigma (in grasses), wall disassembly during fruit ripening, abscission and other cell separation events. Expansins are encoded by two multigene families and each gene is often expressed in highly specific locations and cell types. Structural analysis indicates that one expansin region resembles the catalytic domain of family-45 endoglucanases but glucanase activity has not been detected. The genome projects have revealed numerous expansin-related sequences but their putative wall-loosening functions remain to be assessed.

  7. On the mechanism of the ring zone effect obtained with the mixed haemadsorption technique

    PubMed Central

    Jonsson, J.; Fagraeus, Astrid

    1969-01-01

    A ring zone effect noted with the radial diffusion disc test modification of the mixed haemadsorption technique has been studied using human anti-thyroid sera reacting with thyroid monolayer cultures. Results are presented which suggest that the `empty' centre of the ring zones is due to an excess of attached antibody. Sera giving the ring zone effect contain a larger number of antibody specificities than those producing filled zones. The appearance of ring zones is favoured by a low density of antigens on the culture. These findings and a number of synergistic effects produced by mixing ring and filled zone reactions are compatible with the hypothesis that the ring zone is produced when several antibodies of different specificities react with restricted antigenic areas carrying densely located clusters of antigenic determinants representing the different specificities contained in the ring zone sera. The crowding of antibodies on the clusters in the centre of the ring zones creates a steric hindrance for the indicator cells so that they are not firmly attached in this area. The antibody zone is therefore indicated as a peripheral haemadsorption ring. ImagesFIG. 1FIG. 2FIG. 4FIG. 6FIG. 7FIG. 9 PMID:5307718

  8. Comparison of Mast Cells Count in Odontogenic Cysts Using Histochemical Staining.

    PubMed

    Rajabi-Moghaddam, Mahdieh; Abbaszadeh-Bidokhty, Hamid; Bijani, Ali

    2015-01-01

    Odontogenic cysts are among the most frequent destructive lesions of jaws which their pathogenesis and growth mechanism are not cleared. With respect to different roles of mast cells, they may play a role in the pathogenesis and growth of odontogenic cysts. The aim of present study was to evaluate mast cells in the most common odontogenic cyst. Thirty paraffin-embedded tissue blocks including 10 radicular cysts, 10 dentigerous cysts and 10 odontogenic keratocysts were used and 5 micron sections stained with toluidine blue and observed by light microscope under ×400 magnification to evaluate mast cells within these cysts. For each case, 5 high-power field areas, selected from hot-spot areas, were considered and each area divided into 3 zones: intra-epithelial zone, sub-epithelial zone and deep zone. Most of the studied cyst showed presence of mast cells. There was not any significant difference in mast cell count between studied cysts ( P -values > 0.05).With respect to intra-epithelial, sub-epithelial and deep zones, there was not any significant difference between three studied cysts. There was not any significant difference between sub-epithelial zone and deep zone within each of these cysts. There was only significant difference between intra-epithelial zone and sub-epithelial zone within dentigerous cysts and odontogenic keratocysts ( P -value < 0.05). Prevalence of mast cells in fibrous wall of odontogenic cysts suggests their activity in these cysts. Mast cells may not be directly involved in the pathogenesis of odontogenic keratocysts.

  9. Pegfilgrastim and Rituximab in Treating Patients With Untreated, Relapsed, or Refractory Follicular Lymphoma, Small Lymphocytic Lymphoma, or Marginal Zone Lymphoma

    ClinicalTrials.gov

    2017-09-08

    Contiguous Stage II Grade 1 Follicular Lymphoma; Contiguous Stage II Grade 2 Follicular Lymphoma; Contiguous Stage II Grade 3 Follicular Lymphoma; Contiguous Stage II Marginal Zone Lymphoma; Contiguous Stage II Small Lymphocytic Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Nodal Marginal Zone B-cell Lymphoma; Noncontiguous Stage II Grade 1 Follicular Lymphoma; Noncontiguous Stage II Grade 2 Follicular Lymphoma; Noncontiguous Stage II Grade 3 Follicular Lymphoma; Noncontiguous Stage II Marginal Zone Lymphoma; Noncontiguous Stage II Small Lymphocytic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Small Lymphocytic Lymphoma; Splenic Marginal Zone Lymphoma; Stage I Grade 1 Follicular Lymphoma; Stage I Grade 2 Follicular Lymphoma; Stage I Grade 3 Follicular Lymphoma; Stage I Marginal Zone Lymphoma; Stage I Small Lymphocytic Lymphoma; Stage III Grade 1 Follicular Lymphoma; Stage III Grade 2 Follicular Lymphoma; Stage III Grade 3 Follicular Lymphoma; Stage III Marginal Zone Lymphoma; Stage III Small Lymphocytic Lymphoma; Stage IV Grade 1 Follicular Lymphoma; Stage IV Grade 2 Follicular Lymphoma; Stage IV Grade 3 Follicular Lymphoma; Stage IV Marginal Zone Lymphoma; Stage IV Small Lymphocytic Lymphoma

  10. RhoE deficiency alters postnatal subventricular zone development and the number of calbindin-expressing neurons in the olfactory bulb of mouse.

    PubMed

    Ballester-Lurbe, Begoña; González-Granero, Susana; Mocholí, Enric; Poch, Enric; García-Manzanares, María; Dierssen, Mara; Pérez-Roger, Ignacio; García-Verdugo, José M; Guasch, Rosa M; Terrado, José

    2015-11-01

    The subventricular zone represents an important reservoir of progenitor cells in the adult brain. Cells from the subventricular zone migrate along the rostral migratory stream and reach the olfactory bulb, where they originate different types of interneurons. In this work, we have analyzed the role of the small GTPase RhoE/Rnd3 in subventricular zone cell development using mice-lacking RhoE expression. Our results show that RhoE null mice display a remarkable postnatal broadening of the subventricular zone and caudal rostral migratory stream. This broadening was caused by an increase in progenitor proliferation, observed in the second postnatal week but not before, and by an altered migration of the cells, which appeared in disorganized cell arrangements that impaired the appropriate contact between cells in the rostral migratory stream. In addition, the thickness of the granule cell layer in the olfactory bulb was reduced, although the density of granule cells did not differ between wild-type and RhoE null mice. Finally, the lack of RhoE expression affected the olfactory glomeruli inducing a severe reduction of calbindin-expressing interneurons in the periglomerular layer. This was already evident in the newborns and even more pronounced 15 days later when RhoE null mice displayed 89% less cells than control mice. Our results indicate that RhoE has pleiotropic functions on subventricular cells because of its role in proliferation and tangential migration, affecting mainly the development of calbindin-expressing cells in the olfactory bulb.

  11. 33 CFR 165.154 - Safety and Security Zones; Captain of the Port Long Island Sound Zone Safety and Security Zones.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...; Captain of the Port Long Island Sound Zone Safety and Security Zones. 165.154 Section 165.154 Navigation... Long Island Sound Zone Safety and Security Zones. The following areas are designated safety and... navigable waters of Long Island Sound, from surface to bottom, North and Northeast of a line running from...

  12. 33 CFR 165.154 - Safety and Security Zones: Long Island Sound Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Island Sound Marine Inspection Zone and Captain of the Port Zone. 165.154 Section 165.154 Navigation and... Areas First Coast Guard District § 165.154 Safety and Security Zones: Long Island Sound Marine... this zone is prohibited unless authorized by the Captain of the Port Long, Island Sound. (3) All...

  13. Ethylene and Hormonal Cross Talk in Vegetative Growth and Development1

    PubMed Central

    Van de Poel, Bram; Smet, Dajo; Van Der Straeten, Dominique

    2015-01-01

    Ethylene is a gaseous plant hormone that most likely became a functional hormone during the evolution of charophyte green algae, prior to land colonization. From this ancient origin, ethylene evolved into an important growth regulator that is essential for myriad plant developmental processes. In vegetative growth, ethylene appears to have a dual role, stimulating and inhibiting growth, depending on the species, tissue, and cell type, developmental stage, hormonal status, and environmental conditions. Moreover, ethylene signaling and response are part of an intricate network in cross talk with internal and external cues. Besides being a crucial factor in the growth control of roots and shoots, ethylene can promote flowering, fruit ripening and abscission, as well as leaf and petal senescence and abscission and, hence, plays a role in virtually every phase of plant life. Last but not least, together with jasmonates, salicylate, and abscisic acid, ethylene is important in steering stress responses. PMID:26232489

  14. Ethylene and Hormonal Cross Talk in Vegetative Growth and Development.

    PubMed

    Van de Poel, Bram; Smet, Dajo; Van Der Straeten, Dominique

    2015-09-01

    Ethylene is a gaseous plant hormone that most likely became a functional hormone during the evolution of charophyte green algae, prior to land colonization. From this ancient origin, ethylene evolved into an important growth regulator that is essential for myriad plant developmental processes. In vegetative growth, ethylene appears to have a dual role, stimulating and inhibiting growth, depending on the species, tissue, and cell type, developmental stage, hormonal status, and environmental conditions. Moreover, ethylene signaling and response are part of an intricate network in cross talk with internal and external cues. Besides being a crucial factor in the growth control of roots and shoots, ethylene can promote flowering, fruit ripening and abscission, as well as leaf and petal senescence and abscission and, hence, plays a role in virtually every phase of plant life. Last but not least, together with jasmonates, salicylate, and abscisic acid, ethylene is important in steering stress responses. © 2015 American Society of Plant Biologists. All Rights Reserved.

  15. 76 FR 60802 - Foreign-Trade Zone 77-Memphis, TN; Withdrawal of Request for Temporary/Interim Manufacturing...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-30

    ... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Docket T-4-2011] Foreign-Trade Zone 77--Memphis, TN; Withdrawal of Request for Temporary/Interim Manufacturing Authority; Flextronics Logistics USA, Inc., (Cell Phone/Mobile Handset Kitting). Memphis, TN Notice is hereby given of the withdrawal of the...

  16. The Transcription Factor Bright Plays a Role in Marginal Zone B Lymphocyte Development and Autoantibody Production

    PubMed Central

    Oldham, Athenia L.; Miner, Cathrine A.; Wang, Hong-Cheng; Webb, Carol F.

    2011-01-01

    Previous data suggested that constitutive expression of the transcription factor Bright (B cell regulator of immunoglobulin heavy chain transcription), normally tightly regulated during B cell differentiation, was associated with autoantibody production. Here we show that constitutive Bright expression results in skewing of mature B lineage subpopulations toward marginal zone cells at the expense of the follicular subpopulation. C57Bl/6 transgenic mice constitutively expressing Bright in B lineage cells generated autoantibodies that were not the result of global increases in immunoglobulin or of breaches in key tolerance checkpoints typically defective in other autoimmune mouse models. Rather, autoimmunity correlated with increased numbers of marginal zone B cells and alterations in the phenotype and gene expression profiles of lymphocytes within the follicular B cell compartment. These data suggest a novel role for Bright in the normal development of mature B cell subsets and in autoantibody production. PMID:21963220

  17. Btg1 is Required to Maintain the Pool of Stem and Progenitor Cells of the Dentate Gyrus and Subventricular Zone

    PubMed Central

    Farioli-Vecchioli, Stefano; Micheli, Laura; Saraulli, Daniele; Ceccarelli, Manuela; Cannas, Sara; Scardigli, Raffaella; Leonardi, Luca; Cinà, Irene; Costanzi, Marco; Ciotti, Maria Teresa; Moreira, Pedro; Rouault, Jean-Pierre; Cestari, Vincenzo; Tirone, Felice

    2012-01-01

    Btg1 belongs to a family of cell cycle inhibitory genes. We observed that Btg1 is highly expressed in adult neurogenic niches, i.e., the dentate gyrus and subventricular zone (SVZ). Thus, we generated Btg1 knockout mice to analyze the role of Btg1 in the process of generation of adult new neurons. Ablation of Btg1 causes a transient increase of the proliferating dentate gyrus stem and progenitor cells at post-natal day 7; however, at 2 months of age the number of these proliferating cells, as well as of mature neurons, greatly decreases compared to wild-type controls. Remarkably, adult dentate gyrus stem and progenitor cells of Btg1-null mice exit the cell cycle after completing the S phase, express p53 and p21 at high levels and undergo apoptosis within 5 days. In the SVZ of adult (two-month-old) Btg1-null mice we observed an equivalent decrease, associated to apoptosis, of stem cells, neuroblasts, and neurons; furthermore, neurospheres derived from SVZ stem cells showed an age-dependent decrease of the self-renewal and expansion capacity. We conclude that ablation of Btg1 reduces the pool of dividing adult stem and progenitor cells in the dentate gyrus and SVZ by decreasing their proliferative capacity and inducing apoptosis, probably reflecting impairment of the control of the cell cycle transition from G1 to S phase. As a result, the ability of Btg1-null mice to discriminate among overlapping contextual memories was affected. Btg1 appears, therefore, to be required for maintaining adult stem and progenitor cells quiescence and self-renewal. PMID:22969701

  18. Fusion Protein Cytokine Therapy After Rituximab in Treating Patients With B-Cell Non-Hodgkin Lymphoma

    ClinicalTrials.gov

    2015-06-03

    Anaplastic Large Cell Lymphoma; Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Intraocular Lymphoma; Nodal Marginal Zone B-cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Marginal Zone Lymphoma; Small Intestine Lymphoma; Splenic Marginal Zone Lymphoma; Testicular Lymphoma; Waldenstrom Macroglobulinemia

  19. Capillary zone electrophoresis-tandem mass spectrometry detects low concentration host cell impurities in monoclonal antibodies

    PubMed Central

    Zhu, Guijie; Sun, Liangliang; Heidbrink-Thompson, Jennifer; Kuntumalla, Srilatha; Lin, Hung-yu; Larkin, Christopher J.; McGivney, James B.; Dovichi, Norman J.

    2016-01-01

    We have evaluated capillary zone electrophoresis-electrospray ionization-tandem mass spectrometry (CZE-ESI-MS/MS) for detection of trace amounts of host cell protein impurities in recombinant therapeutics. Compared to previously published procedures, we have optimized the buffer pH used in the formation of a pH junction to increase injection volume. We also prepared a five-point calibration curve by spiking twelve standard proteins into a solution of a human monoclonal antibody. A custom CZE-MS/MS system was used to analyze the tryptic digest of this mixture without depletion of the antibody. CZE generated a ~70 min separation window (~90 min total analysis duration) and ~300 peak capacity. We also analyzed the sample using ultra-performance liquid chromatography (UPLC)-MS/MS. CZE-MS/MS generated ~five times higher base peak intensity and more peptide identifications for low-level spiked proteins. Both methods detected all proteins spiked at the ~100 ppm level with respect to the antibody. PMID:26530276

  20. Discovery of benzo[e]pyridoindolones as kinase inhibitors that disrupt mitosis exit while erasing AMPK-Thr172 phosphorylation on the spindle.

    PubMed

    Le, Ly-Thuy-Tram; Couvet, Morgane; Favier, Bertrand; Coll, Jean-Luc; Nguyen, Chi-Hung; Molla, Annie

    2015-09-08

    Aurora kinases play an essential role in mitotic progression and are attractive targets in cancer therapy. The first generation of benzo[e]pyridoindole exhibited powerful aurora kinase inhibition but their low solubility limited further development. Grafting a pyperidine-ethoxy group gives rise to a hydrosoluble inhibitor: compound C5M.C5M could efficiently inhibit the proliferation of cells from different origins. C5M prevented cell cycling, induced a strong mitotic arrest then, cells became polyploid and finally died. C5M did not impair the spindle checkpoint, the separation of the sister chromatids and the transfer of aurora B on the mid-zone. C5M prevented histone H3 phosphorylation at mitotic entry and erased AMPK-Thr172 phosphorylation in late mitosis. With this unique profile of inhibition, C5M could be useful for understanding the role of phospho-Thr172-AMPK in abscission and the relationship between the chromosomal complex and the energy sensing machinery.C5M is a multikinase inhibitor with interesting preclinical characteristics: high hydro-solubility and a good stability in plasma. A single dose prevents the expansion of multicellular spheroids. C5M can safely be injected to mice and reduces significantly the development of xenograft. The next step will be to define the protocol of treatment and the cancer therapeutic field of this new anti-proliferative drug.

  1. Marginal zone lymphoma: old, new, targeted, and epigenetic therapies

    PubMed Central

    Joshi, Monika; Sheikh, Hassan; Abbi, Kamal; Long, Sarah; Sharma, Kamal; Tulchinsky, Mark

    2012-01-01

    Marginal zone lymphoma (MZL) is an indolent B-cell lymphoma arising from marginal zone B-cells present in lymph nodes and extranodal tissues. MZL comprises 5–17% of all non-Hodgkin’s lymphomas in adults. The World Health Organization categorizes MZL into three distinct types based on their site of impact: (1) splenic marginal zone lymphoma (SMZL); (2) nodal marginal zone lymphoma (NMZL); (3) extranodal mucosa-associated lymphoid tissue (MALT) lymphoma, which can be subdivided into gastric and nongastric. The subgroups of MZL share some common features but are different in their biology and behavior. Owing to the rarity of MZL there are few randomized trials available comparing various treatment options and therefore treatment is controversial, lacking standard guidelines. Treatment should be patient tailored and can range from a ‘watchful waiting’ approach for asymptomatic patients without cytopenias to surgery or localized radiation therapy. Rituximab in combination with chemotherapy has resulted in longer failure-free survival than chemotherapy alone in patients with SMZL. Helicobacter pylori positive gastric MALT shows a good response rate to triple antibiotic therapy. Newer therapies such as bendamustine, everolimus, lenalidomide, vorinostat and phosphoinositide 3-kinase inhibitors are in clinical trials for patients with relapsed or refractory MZL and have shown promising results. We are presently conducting clinical trials testing the efficacy of the epigenetic activity of cladribine as a hypomethylating agent in combination with the histone deacetylase inhibitor (HDACi) vorinostat and rituximab in patients with MZL. Further studies with the newer agents should be done both in newly diagnosed or relapsed/refractory MZL to streamline the care and to avoid the use of toxic chemotherapies as initial treatment. PMID:23616915

  2. Rituximab and Interleukin-12 in Treating Patients With B-Cell Non-Hodgkin's Lymphoma

    ClinicalTrials.gov

    2013-08-23

    Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Nodal Marginal Zone B-cell Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Small Lymphocytic Lymphoma; Splenic Marginal Zone Lymphoma

  3. Comparative analysis of glucagonergic cells, glia and the circumferential marginal zone in the reptilian retina

    PubMed Central

    Todd, Levi; Suarez, Lilianna; Squires, Natalie; Zelinka, Christopher Paul; Gribbins, Kevin; Fischer, Andy J.

    2015-01-01

    Retinal progenitors in the circumferential margin zone (CMZ) and Müller glia-derived progenitors have been well-described in the eyes of fish, amphibians and birds. However, there is no information regarding a CMZ and the nature of retinal glia in species phylogenetically bridging amphibians and birds. Thus, the purpose of this study was to examine the retinal glia and investigate whether a CMZ is present in the eyes of reptilian species. We used immuno-histochemical analyses to study retinal glia, neurons that could influence CMZ-progenitors, the retinal margin, and non-pigmented epithelium (NPE) of ciliary body of garter snakes, queen snakes, anole lizards, snapping turtles, and painted turtles. We compare our observations in reptile eyes to the CMZ and glia of fish, amphibians and birds. In all species, Sox9, Pax6 and the glucocorticoid receptor are expressed by Müller glia and cells at the retinal margin. However, proliferating cells were found only in the CMZ of turtles, but not in the eyes of anoles and snakes. Similar to eyes of chickens, the retinal margin in turtles contains accumulations of GLP1/glucagonergic neurites. We find that filamentous proteins, vimentin and GFAP, are expressed by Müller glia, but have different patterns of sub-cellular localization in the different species of reptiles. We provide evidence that the reptile retina may contain Non-astrocytic Inner Retinal Glial (NIRG) cells, similar to those described in the avian retina. We conclude that the retinal glia, glucagonergic neurons and CMZ of turtles appears to be the most similar to that of fish, amphibians and birds. PMID:26053997

  4. Ventricular Zone Disruption in Human Neonates With Intraventricular Hemorrhage.

    PubMed

    McAllister, James P; Guerra, Maria Montserrat; Ruiz, Leandro Castaneyra; Jimenez, Antonio J; Dominguez-Pinos, Dolores; Sival, Deborah; den Dunnen, Wilfred; Morales, Diego M; Schmidt, Robert E; Rodriguez, Esteban M; Limbrick, David D

    2017-05-01

    To determine if ventricular zone (VZ) and subventricular zone (SVZ) alterations are associated with intraventricular hemorrhage (IVH) and posthemorrhagic hydrocephalus, we compared postmortem frontal and subcortical brain samples from 12 infants with IVH and 3 nonneurological disease controls without hemorrhages or ventriculomegaly. Birth and expiration estimated gestational ages were 23.0-39.1 and 23.7-44.1 weeks, respectively; survival ranges were 0-42 days (median, 2.0 days). Routine histology and immunohistochemistry for neural stem cells (NSCs), neural progenitors (NPs), multiciliated ependymal cells (ECs), astrocytes (AS), and cell adhesion molecules were performed. Controls exhibited monociliated NSCs and multiciliated ECs lining the ventricles, abundant NPs in the SVZ, and medial vs. lateral wall differences with a complex mosaic organization in the latter. In IVH cases, normal VZ/SVZ areas were mixed with foci of NSC and EC loss, eruption of cells into the ventricle, cytoplasmic transposition of N-cadherin, subependymal rosettes, and periventricular heterotopia. Mature AS populated areas believed to be sites of VZ disruption. The cytopathology and extension of the VZ disruption correlated with developmental age but not with brain hemorrhage grade or location. These results corroborate similar findings in congenital hydrocephalus in animals and humans and indicate that VZ disruption occurs consistently in premature neonates with IVH. © 2017 American Association of Neuropathologists, Inc. All rights reserved.

  5. 75 FR 53638 - Approval for Manufacturing Authority; Foreign-Trade Zone 22; LG Electronics Mobilecomm USA, Inc...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-01

    ... Authority; Foreign-Trade Zone 22; LG Electronics Mobilecomm USA, Inc. (Cell Phone Kitting and Distribution... authority on behalf of LG Electronics Mobilecomm USA, Inc. (LGEMU), within FTZ 22 in Bolingbrook, Illinois... application for manufacturing authority under zone procedures within FTZ 22 on behalf of LG Electronics...

  6. 77 FR 59374 - Foreign-Trade Zone 126-Reno, NV, Withdrawal of Production Notification, Brightpoint North America...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-27

    ... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Docket B-37-2012] Foreign-Trade Zone 126--Reno, NV, Withdrawal of Production Notification, Brightpoint North America L.P. (Cell Phone Kitting and Distribution), Reno, NV Notice is hereby given of the withdrawal of the notification of the Economic...

  7. Comparison of Mast Cells Count in Odontogenic Cysts Using Histochemical Staining

    PubMed Central

    Rajabi-Moghaddam, Mahdieh; Abbaszadeh-Bidokhty, Hamid; Bijani, Ali

    2015-01-01

    Background & Objectives: Odontogenic cysts are among the most frequent destructive lesions of jaws which their pathogenesis and growth mechanism are not cleared. With respect to different roles of mast cells, they may play a role in the pathogenesis and growth of odontogenic cysts. The aim of present study was to evaluate mast cells in the most common odontogenic cyst. Methods: Thirty paraffin-embedded tissue blocks including 10 radicular cysts, 10 dentigerous cysts and 10 odontogenic keratocysts were used and 5 micron sections stained with toluidine blue and observed by light microscope under ×400 magnification to evaluate mast cells within these cysts. For each case, 5 high-power field areas, selected from hot-spot areas, were considered and each area divided into 3 zones: intra-epithelial zone, sub-epithelial zone and deep zone. Results: Most of the studied cyst showed presence of mast cells. There was not any significant difference in mast cell count between studied cysts ( P -values > 0.05).With respect to intra-epithelial, sub-epithelial and deep zones, there was not any significant difference between three studied cysts. There was not any significant difference between sub-epithelial zone and deep zone within each of these cysts. There was only significant difference between intra-epithelial zone and sub-epithelial zone within dentigerous cysts and odontogenic keratocysts ( P -value < 0.05). Conclusions: Prevalence of mast cells in fibrous wall of odontogenic cysts suggests their activity in these cysts. Mast cells may not be directly involved in the pathogenesis of odontogenic keratocysts. PMID:26351470

  8. 76 FR 22033 - Safety Zone; Red River Safety Zone, Red River, MN

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-20

    ...-AAOO Safety Zone; Red River Safety Zone, Red River, MN AGENCY: Coast Guard, DHS. ACTION: Temporary... a temporary safety zone on the Red River, MN. This safety zone is being established to ensure the... Red River in the State of Minnesota north of a line drawn across latitude 46[deg]20'00'' N, including...

  9. Zone lines

    Treesearch

    Kevin T. Smith

    2001-01-01

    Zone lines are narrow, usually dark markings formed in decaying wood. Zone lines are found most frequently in advanced white rot of hardwoods, although they occasionally are associated both with brown rot and with softwoods.

  10. The effect of adipose derived stromal vascular fraction on stasis zone in an experimental burn model.

    PubMed

    Eyuboglu, Atilla Adnan; Uysal, Cagri A; Ozgun, Gonca; Coskun, Erhan; Markal Ertas, Nilgun; Haberal, Mehmet

    2018-03-01

    Stasis zone is the surrounding area of the coagulation zone which is an important part determining the extent of the necrosis in burn patients. In our study we aim to salvage the stasis zone by injecting adipose derived stromal vascular fraction (ADSVF). Thermal injury was applied on dorsum of Sprague-Dawley rats (n=20) by the "comb burn" model as described previously. When the burn injury was established on Sprague-Dawley rats (30min); rat dorsum was separated into 2 equal parts consisting of 4 burn zones (3 stasis zone) on each pair. ADSVF cells harvested from inguinal fat pads of Sprague-Dawley rats (n=5) were injected on the right side while same amount of phosphate buffered saline (PBS) injected on the left side of the same animal. One week later, average vital tissue on the statis zone was determined by macroscopy, angiography and microscopy. Vascular density, inflammatory cell density, gradient of fibrosis and epithelial thickness were determined via immunohistochemical assay. Macroscopic stasis zone tissue viability (32±3.28%, 57±4.28%) (p<0.01), average number of vessels (10.28±1.28, 19.43±1.72) (p<0.01), capillary count (15.67±1.97, 25.35±2.15) (p<0.01) vascular density (1.55±0.38, 2.14±0.45) (p<0.01) epithelial thickness (0.014±0.009mm, 0.024±0.0011mm) were higher on ADSVF side. Fibrosis gradient (1.87±0.51, 1.50±0.43) (p<0.01) and inflammatory cell density (1.33±0.40, 1.20±0.32) (p<0.01) were higher on the PBS side. Macroscopic and microscopic findings determined that ADSVF has a statistically significant benefit for salvaging stasis zone on acute burn injuries. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

  11. Symmetrical primary cutaneous marginal zone lymphoma associated with rheumatoid arthritis.

    PubMed

    Yildirim, Fatma Elif; Karaduman, Ayşen; Hürmüz, Pervin; Ozyar, Enis; Barişta, Ibrahim; Sağlam, Arzu

    2010-05-01

    Primary cutaneous marginal zone B-cell lymphoma (PCMZL) is an indolent low grade B cell lymphoma of the skin, with lack of extracutaneous involvement at the time of diagnosis. Herein we report the case of a patient with rheumatoid arthritis (RA) who developed symmetrical PCMZL lesions on both ear lobes. Lesions occurring symmetrically on ear lobes are more specific for cutaneous lymphoid hyperplasia (CLH) and this kind of symmetrical localization hasn't been reported for PCMZL before. PCMZL is considered to arise from a background of reactive lymphoid hyperplasia and this case point out the concept of CLH and PCMZL spectrum. Association of marginal zone lymphoma with rheumatoid arthritis and resolution of lesions together with the resolution of symptoms due to rheumatoid arthritis after rituximab therapy is another interesting point for this case. To the best of our knowledge PCMZL associated with RA has not been reported previously.

  12. The effect of a low potassium diet on the glomerular zone of the adrenal cortex of rats.

    PubMed

    Kawai, K; Sugihara, H; Tsuchiyama, H

    1979-05-01

    Rats were fed on low potassium diets in order to observe the effect of dietary low potassium on the adrenal cortex. The authors clarified morphological changes of the hypofunctional glomerular zone and compared these changes with those of the hyperfunctional glomerular zone. Three weeks after or 2 months after the start of a low potassium diet, slight narrowing of the glomerular zone of the adrenal cortex was observed followed by miniaturization of cells, presence of binuclear cells and an increase of lipid with enlarged lipid drops. Electron microscope mainly disclosed changes of mitochondrial cristae consisting of markedly reduced, enlarged and irregularly dilated cristae with shortening or elongation. Granules appeared in mitochondria. Lysosomes or dense bodies were enlarged. The Golgi's apparatus was atrophied but endoplasmic reticulum did not show remarkable changes. These changes were directly opposite to those of the hyperfunctional glomerular zone noted after a pottasium load or seen in sodium deficiency. Consequently, these changes were considered to be the changes of the hypofunctional glomerular zone associated with decrease of aldosterone production.

  13. Controls on Mixing-Dependent Denitrification in Hyporheic Zones

    NASA Astrophysics Data System (ADS)

    Hester, E. T.; Young, K. I.; Widdowson, M. A.

    2013-12-01

    Interaction of surface water and groundwater in hyporheic sediments of river systems is known to create unique biogeochemical conditions that can attenuate contaminants flowing downstream. Oxygen, carbon, and the contaminants themselves (e.g., excess nitrate) often advect together through the hyporheic zone from sources in surface water. However, the ability of the hyporheic zone to attenuate contaminants in upwelling groundwater plumes as they exit to rivers is less known. Such reactions may be more dependent on mixing of carbon and oxygen sources from surface water with contaminants from deeper groundwater. We simulated hyporheic flow cells and upwelling groundwater together with mixing-dependent denitrification of an upwelling nitrate plume in shallow riverbed sediments using MODFLOW and SEAM3D. For our first set of model scenarios, we set biogeochemical boundary conditions to be consistent with situations where only mixing-dependent denitrification occurred within the model domain. This occurred where dissolved organic carbon (DOC) advecting from surface water through hyporheic flow cells meets nitrate upwelling from deeper groundwater. This would be common where groundwater is affected by septic systems which contribute nitrate that upwells into streams that do not have significant nitrate sources from upstream. We conducted a sensitivity analysis that showed that mixing-dependent denitrification increased with parameters that increase mixing itself, such as the degree of heterogeneity of sediment hydraulic conductivity (K). Mixing-dependent denitrification also increased with certain biogeochemical boundary concentrations such as increasing DOC or decreasing dissolved oxygen (DO) advecting from surface water. For our second set of model scenarios, we set biogeochemical boundary conditions to be consistent with common situations where non-mixing-dependent denitrification also occurred within the model domain. For example, when nitrate concentrations are

  14. Study of BKM120 & Rituximab in Patients With Relapsed or Refractory Indolent B-Cell Lymphoma

    ClinicalTrials.gov

    2017-09-12

    Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Nodal Marginal Zone B-cell Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Splenic Marginal Zone Lymphoma; Waldenström Macroglobulinemia

  15. The carbocyanine dye DiD labels in vitro and in vivo neural stem cells of the subventricular zone as well as myelinated structures following in vivo injection in the lateral ventricle.

    PubMed

    Carradori, Dario; Barreau, Kristell; Eyer, Joël

    2016-02-01

    Carbocyanines are fluorescent lipophilic cationic dyes used since the early 1980s as neuronal tracers. Several applications of these compounds have been developed thanks to their low cell toxicity, lateral diffusion within the cellular membranes, and good photostability. 1,1'-Dioctadecyl-3,3,3',3'-tetramethylindodicarbocyanine 4-chlorobenzenesulfonate (DiD) is an interesting component of this family because, in addition to the classic carbocyanine properties, it has a longer wavelength compared with its analogues. That makes DiD an excellent carbocyanine for labeling cells and tissues with significant intrinsic fluorescence. Drug encapsulation, drug delivery, and cellular transplantation are also fields using DiD-based systems where having detailed knowledge about its behavior as a single entity is important. Recently, promising studies concerned neural stem cells from the subventricular zone of the lateral ventricle in the brain (their natural niche) and their potential therapeutic use. Here, we show that DiD is able to label these stem cells in vitro and present basilar information concerning its pharmacokinetics, concentrations, and microscope protocols. Moreover, when DiD is injected in vivo in the cerebrospinal fluid present in the lateral ventricle of rat, it also labels stem cells as well as myelinated structures of the caudoputamen. This analysis provides a database to consult when planning experiments concerning DiD and neural stem cells from the subventricular zone. © 2015 Wiley Periodicals, Inc.

  16. Providing plastic zone extrusion

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

    Manchiraju, Venkata Kiran; Feng, Zhili; David, Stan A.

    Plastic zone extrusion may be provided. First, a compressor may generate frictional heat in stock to place the stock in a plastic zone of the stock. Then, a conveyer may receive the stock in its plastic zone from the compressor and transport the stock in its plastic zone from the compressor. Next, a die may receive the stock in its plastic zone from the conveyer and extrude the stock to form a wire.

  17. Fault zone hydrogeology

    NASA Astrophysics Data System (ADS)

    Bense, V. F.; Gleeson, T.; Loveless, S. E.; Bour, O.; Scibek, J.

    2013-12-01

    Deformation along faults in the shallow crust (< 1 km) introduces permeability heterogeneity and anisotropy, which has an important impact on processes such as regional groundwater flow, hydrocarbon migration, and hydrothermal fluid circulation. Fault zones have the capacity to be hydraulic conduits connecting shallow and deep geological environments, but simultaneously the fault cores of many faults often form effective barriers to flow. The direct evaluation of the impact of faults to fluid flow patterns remains a challenge and requires a multidisciplinary research effort of structural geologists and hydrogeologists. However, we find that these disciplines often use different methods with little interaction between them. In this review, we document the current multi-disciplinary understanding of fault zone hydrogeology. We discuss surface- and subsurface observations from diverse rock types from unlithified and lithified clastic sediments through to carbonate, crystalline, and volcanic rocks. For each rock type, we evaluate geological deformation mechanisms, hydrogeologic observations and conceptual models of fault zone hydrogeology. Outcrop observations indicate that fault zones commonly have a permeability structure suggesting they should act as complex conduit-barrier systems in which along-fault flow is encouraged and across-fault flow is impeded. Hydrogeological observations of fault zones reported in the literature show a broad qualitative agreement with outcrop-based conceptual models of fault zone hydrogeology. Nevertheless, the specific impact of a particular fault permeability structure on fault zone hydrogeology can only be assessed when the hydrogeological context of the fault zone is considered and not from outcrop observations alone. To gain a more integrated, comprehensive understanding of fault zone hydrogeology, we foresee numerous synergistic opportunities and challenges for the discipline of structural geology and hydrogeology to co-evolve and

  18. Wnt/β-catenin signaling integrates patterning and metabolism of the insect growth zone.

    PubMed

    Oberhofer, Georg; Grossmann, Daniela; Siemanowski, Janna L; Beissbarth, Tim; Bucher, Gregor

    2014-12-01

    Wnt/β-catenin and hedgehog (Hh) signaling are essential for transmitting signals across cell membranes in animal embryos. Early patterning of the principal insect model, Drosophila melanogaster, occurs in the syncytial blastoderm, where diffusion of transcription factors obviates the need for signaling pathways. However, in the cellularized growth zone of typical short germ insect embryos, signaling pathways are predicted to play a more fundamental role. Indeed, the Wnt/β-catenin pathway is required for posterior elongation in most arthropods, although which target genes are activated in this context remains elusive. Here, we use the short germ beetle Tribolium castaneum to investigate two Wnt and Hh signaling centers located in the head anlagen and in the growth zone of early embryos. We find that Wnt/β-catenin signaling acts upstream of Hh in the growth zone, whereas the opposite interaction occurs in the head. We determine the target gene sets of the Wnt/β-catenin and Hh pathways and find that the growth zone signaling center activates a much greater number of genes and that the Wnt and Hh target gene sets are essentially non-overlapping. The Wnt pathway activates key genes of all three germ layers, including pair-rule genes, and Tc-caudal and Tc-twist. Furthermore, the Wnt pathway is required for hindgut development and we identify Tc-senseless as a novel hindgut patterning gene required in the early growth zone. At the same time, Wnt acts on growth zone metabolism and cell division, thereby integrating growth with patterning. Posterior Hh signaling activates several genes potentially involved in a proteinase cascade of unknown function. © 2014. Published by The Company of Biologists Ltd.

  19. Wnt/β-catenin signaling integrates patterning and metabolism of the insect growth zone

    PubMed Central

    Oberhofer, Georg; Grossmann, Daniela; Siemanowski, Janna L.; Beissbarth, Tim; Bucher, Gregor

    2014-01-01

    Wnt/β-catenin and hedgehog (Hh) signaling are essential for transmitting signals across cell membranes in animal embryos. Early patterning of the principal insect model, Drosophila melanogaster, occurs in the syncytial blastoderm, where diffusion of transcription factors obviates the need for signaling pathways. However, in the cellularized growth zone of typical short germ insect embryos, signaling pathways are predicted to play a more fundamental role. Indeed, the Wnt/β-catenin pathway is required for posterior elongation in most arthropods, although which target genes are activated in this context remains elusive. Here, we use the short germ beetle Tribolium castaneum to investigate two Wnt and Hh signaling centers located in the head anlagen and in the growth zone of early embryos. We find that Wnt/β-catenin signaling acts upstream of Hh in the growth zone, whereas the opposite interaction occurs in the head. We determine the target gene sets of the Wnt/β-catenin and Hh pathways and find that the growth zone signaling center activates a much greater number of genes and that the Wnt and Hh target gene sets are essentially non-overlapping. The Wnt pathway activates key genes of all three germ layers, including pair-rule genes, and Tc-caudal and Tc-twist. Furthermore, the Wnt pathway is required for hindgut development and we identify Tc-senseless as a novel hindgut patterning gene required in the early growth zone. At the same time, Wnt acts on growth zone metabolism and cell division, thereby integrating growth with patterning. Posterior Hh signaling activates several genes potentially involved in a proteinase cascade of unknown function. PMID:25395458

  20. Earthquake Complex Network applied along the Chilean Subduction Zone.

    NASA Astrophysics Data System (ADS)

    Martin, F.; Pasten, D.; Comte, D.

    2017-12-01

    In recent years the earthquake complex networks have been used as a useful tool to describe and characterize the behavior of seismicity. The earthquake complex network is built in space, dividing the three dimensional space in cubic cells. If the cubic cell contains a hypocenter, we call this cell like a node. The connections between nodes follows the time sequence of the occurrence of the seismic events. In this sense, we have a spatio-temporal configuration of a specific region using the seismicity in that zone. In this work, we are applying complex networks to characterize the subduction zone along the coast of Chile using two networks: a directed and an undirected network. The directed network takes in consideration the time-direction of the connections, that is very important for the connectivity of the network: we are considering the connectivity, ki of the i-th node, like the number of connections going out from the node i and we add the self-connections (if two seismic events occurred successive in time in the same cubic cell, we have a self-connection). The undirected network is the result of remove the direction of the connections and the self-connections from the directed network. These two networks were building using seismic data events recorded by CSN (Chilean Seismological Center) in Chile. This analysis includes the last largest earthquakes occurred in Iquique (April 2014) and in Illapel (September 2015). The result for the directed network shows a change in the value of the critical exponent along the Chilean coast. The result for the undirected network shows a small-world behavior without important changes in the topology of the network. Therefore, the complex network analysis shows a new form to characterize the Chilean subduction zone with a simple method that could be compared with another methods to obtain more details about the behavior of the seismicity in this region.

  1. Spatial gradients in cell wall composition and transcriptional profiles along elongating maize internodes

    PubMed Central

    2014-01-01

    Background The elongating maize internode represents a useful system for following development of cell walls in vegetative cells in the Poaceae family. Elongating internodes can be divided into four developmental zones, namely the basal intercalary meristem, above which are found the elongation, transition and maturation zones. Cells in the basal meristem and elongation zones contain mainly primary walls, while secondary cell wall deposition accelerates in the transition zone and predominates in the maturation zone. Results The major wall components cellulose, lignin and glucuronoarabinoxylan (GAX) increased without any abrupt changes across the elongation, transition and maturation zones, although GAX appeared to increase more between the elongation and transition zones. Microarray analyses show that transcript abundance of key glycosyl transferase genes known to be involved in wall synthesis or re-modelling did not match the increases in cellulose, GAX and lignin. Rather, transcript levels of many of these genes were low in the meristematic and elongation zones, quickly increased to maximal levels in the transition zone and lower sections of the maturation zone, and generally decreased in the upper maturation zone sections. Genes with transcript profiles showing this pattern included secondary cell wall CesA genes, GT43 genes, some β-expansins, UDP-Xylose synthase and UDP-Glucose pyrophosphorylase, some xyloglucan endotransglycosylases/hydrolases, genes involved in monolignol biosynthesis, and NAM and MYB transcription factor genes. Conclusions The data indicated that the enzymic products of genes involved in cell wall synthesis and modification remain active right along the maturation zone of elongating maize internodes, despite the fact that corresponding transcript levels peak earlier, near or in the transition zone. PMID:24423166

  2. Seed zones and breeding zones for sugar pine in southwestern Oregon.

    Treesearch

    Robert K. Campbell; Albert I. Sugano

    1987-01-01

    Provisional seed zones and breeding zones were developed for sugar pine (Pinus lambertiana Dougl.) in southwestern Oregon. Zones are based on a map of genetic variation patterns obtained by evaluating genotypes of trees from 142 locations in the region. Genotypes controlling growth vigor and growth rhythm were assessed in a common garden. Within...

  3. A two-dimensional time domain near zone to far zone transformation

    NASA Technical Reports Server (NTRS)

    Luebbers, Raymond J.; Ryan, Deirdre; Beggs, John H.; Kunz, Karl S.

    1991-01-01

    A time domain transformation useful for extrapolating three dimensional near zone finite difference time domain (FDTD) results to the far zone was presented. Here, the corresponding two dimensional transform is outlined. While the three dimensional transformation produced a physically observable far zone time domain field, this is not convenient to do directly in two dimensions, since a convolution would be required. However, a representative two dimensional far zone time domain result can be obtained directly. This result can then be transformed to the frequency domain using a Fast Fourier Transform, corrected with a simple multiplicative factor, and used, for example, to calculate the complex wideband scattering width of a target. If an actual time domain far zone result is required, it can be obtained by inverse Fourier transform of the final frequency domain result.

  4. Detection of L265P MYD-88 mutation in a series of clonal B-cell lymphocytosis of marginal zone origin (CBL-MZ).

    PubMed

    Kalpadakis, Christina; Pangalis, Gerassimos A; Vassilakopoulos, Theodoros P; Roumelioti, Maria; Sachanas, Sotirios; Korkolopoulou, Penelope; Koulieris, Efstathios; Moschogiannis, Maria; Yiakoumis, Xanthi; Tsirkinidis, Pantelis; Pontikoglou, Charalampos; Rondoyianni, Dimitra; Papadaki, Helen A; Panayiotidis, Panayiotidis; Angelopoulou, Maria K

    2017-12-01

    Clonal B-cell lymphocytosis of marginal zone origin (CBL-MZ) is a recently described entity characterized by the presence of clonal B cells in the blood and/or bone marrow (BM) with morphologic and immunophenotypic features consistent with marginal zone derivation in otherwise healthy individuals. CBL-MZ is commonly associated with paraproteinemia, usually immunoglobulin M (IgM), raising diagnostic difficulties from Waldenstrom macroglobulinemia (WM). The aim of the present study was to determine the presence of MYD-88 L265P mutation in a well-characterized series of CBL-MZ to identify cases that may in fact represent WM. Fifty-three CBL-MZ cases were retrospectively evaluated. MYD-88 L265P mutation was determined by allele-specific polymerase chain reaction in blood and/or BM mononuclear cells. Almost half of the CBL-MZ cases (49%) were associated with paraproteinemia mainly of the IgM type (65%). MYD-88 L265P mutation was identified in 10 cases (19%). These cases may truly represent WM, whereas 43 cases (81%) are still classified as CBL-MZ. Mutated cases were all associated with paraproteinemia compared with 37% of the nonmutated ones (P < .0001). In addition, mutated cases displayed more frequently CD38 and CD25 positivity (P = .002 and P = .005, respectively). Moreover, cases without paraproteinemia presented more frequently with lymphocytosis, irrespective of the presence of the MYD-88 mutation (P = .02). The present study demonstrates that MYD-88 L265P mutation may represent the only sensitive marker for the differentiation of CBL-MZ from probable WM. However, further studies are warranted to better define the biological significance of MYD-88 L265P mutation and to clarify whether the presence of the mutation establishes WM diagnosis or that it can also be present in borderline cases associated with paraproteinemia. Copyright © 2016 John Wiley & Sons, Ltd.

  5. The N2 paradox: similar outcomes of pre- and postoperatively identified single-zone N2a positive non-small-cell lung cancer.

    PubMed

    Tsitsias, Thomas; Boulemden, Anas; Ang, Keng; Nakas, Apostolos; Waller, David A

    2014-05-01

    Resection of N2a non-small-cell lung cancer (NSCLC) diagnosed preoperatively is controversial but there is support for resection of unexpected N2 disease discovered at surgery. Since the seventh TNM edition, we have intentionally resected clinical N2a disease. To validate this policy, we determined prognostic factors associated with all resected N2 disease. From a prospective database of 1131 consecutive patients undergoing elective resection for primary lung cancer over a period of 8 years, we identified 68 patients (35 females (51.4%), mean age 66 years, standard deviation (SD) 9 years) who had pathological N2 disease. All patients had positron emission computed tomography (CT-PET) staging and selective mediastinoscopy. A Cox-regression analysis was performed to identify prognostic factors. At a median follow-up of 38.7 months (standard error 10, 95% confidence interval (CI) 19.0-58.4), the overall median survival was 22.2 months (95% CI 14.6-29.8) with 1-, 2- and 5-year survival rates of 63.3, 46.6 and 13.2%, respectively. Survival after resection of pN2 disease is adversely affected by the need for pneumonectomy, multizone pN2b involvement and by non-compliance with adjuvant chemotherapy. Pathological involvement of the subcarinal zone but no other zone appears to be associated with an adverse prognosis (hazard ratio (HR) 1.87, P = 0.063). Importantly, long-term survival is not different between those patients who have a negative preoperative PET-CT scan and yet are found to have pN2 after resection, and those who are single-zone cN2a positive before resection on PET-CT scan (HR 1.37, P = 0.335). Our results support a policy of intentionally resecting single-zone N2a NSCLC identified preoperatively as part of a multimodality therapy.

  6. Transforming growth factor β-induced superficial zone protein accumulation in the surface zone of articular cartilage is dependent on the cytoskeleton.

    PubMed

    McNary, Sean M; Athanasiou, Kyriacos A; Reddi, A Hari

    2014-03-01

    The phenotype of articular chondrocytes is dependent on the cytoskeleton, specifically the actin microfilament architecture. Articular chondrocytes in monolayer culture undergo dedifferentiation and assume a fibroblastic phenotype. This process can be reversed by altering the actin cytoskeleton by treatment with cytochalasin. Whereas dedifferentiation has been studied on chondrocytes isolated from the whole cartilage, the effects of cytoskeletal alteration on specific zones of cells such as superficial zone chondrocytes are not known. Chondrocytes from the superficial zone secrete superficial zone protein (SZP), a lubricating proteoglycan that reduces the coefficient of friction of articular cartilage. A better understanding of this phenomenon may be useful in elucidating chondrocyte dedifferentiation in monolayer and accumulation of the cartilage lubricant SZP, with an eye toward tissue engineering functional articular cartilage. In this investigation, the effects of cytoskeletal modulation on the ability of superficial zone chondrocytes to secrete SZP were examined. Primary superficial zone chondrocytes were cultured in monolayer and treated with a combination of cytoskeleton modifying reagents and transforming growth factor β (TGFβ) 1, a critical regulator of SZP production. Whereas cytochalasin D maintains the articular chondrocyte phenotype, the hallmark of the superficial zone chondrocyte, SZP, was inhibited in the presence of TGFβ1. A decrease in TGFβ1-induced SZP accumulation was also observed when the microtubule cytoskeleton was modified using paclitaxel. These effects of actin and microtubule alteration were confirmed through the application of jasplakinolide and colchicine, respectively. As Rho GTPases regulate actin organization and microtubule polymerization, we hypothesized that the cytoskeleton is critical for TGFβ-induced SZP accumulation. TGFβ-mediated SZP accumulation was inhibited by small molecule inhibitors ML141 (Cdc42), NSC23766 (Rac1

  7. The Sorong Fault Zone, Indonesia: Mapping a Fault Zone Offshore

    NASA Astrophysics Data System (ADS)

    Melia, S.; Hall, R.

    2017-12-01

    The Sorong Fault Zone is a left-lateral strike-slip fault zone in eastern Indonesia, extending westwards from the Bird's Head peninsula of West Papua towards Sulawesi. It is the result of interactions between the Pacific, Caroline, Philippine Sea, and Australian Plates and much of it is offshore. Previous research on the fault zone has been limited by the low resolution of available data offshore, leading to debates over the extent, location, and timing of movements, and the tectonic evolution of eastern Indonesia. Different studies have shown it north of the Sula Islands, truncated south of Halmahera, continuing to Sulawesi, or splaying into a horsetail fan of smaller faults. Recently acquired high resolution multibeam bathymetry of the seafloor (with a resolution of 15-25 meters), and 2D seismic lines, provide the opportunity to trace the fault offshore. The position of different strands can be identified. On land, SRTM topography shows that in the northern Bird's Head the fault zone is characterised by closely spaced E-W trending faults. NW of the Bird's Head offshore there is a fold and thrust belt which terminates some strands. To the west of the Bird's Head offshore the fault zone diverges into multiple strands trending ENE-WSW. Regions of Riedel shearing are evident west of the Bird's Head, indicating sinistral strike-slip motion. Further west, the ENE-WSW trending faults turn to an E-W trend and there are at least three fault zones situated immediately south of Halmahera, north of the Sula Islands, and between the islands of Sanana and Mangole where the fault system terminates in horsetail strands. South of the Sula islands some former normal faults at the continent-ocean boundary with the North Banda Sea are being reactivated as strike-slip faults. The fault zone does not currently reach Sulawesi. The new fault map differs from previous interpretations concerning the location, age and significance of different parts of the Sorong Fault Zone. Kinematic

  8. A two-dimensional time domain near zone to far zone transformation

    NASA Technical Reports Server (NTRS)

    Luebbers, Raymond J.; Ryan, Deirdre; Beggs, John H.; Kunz, Karl S.

    1991-01-01

    In a previous paper, a time domain transformation useful for extrapolating 3-D near zone finite difference time domain (FDTD) results to the far zone was presented. In this paper, the corresponding 2-D transform is outlined. While the 3-D transformation produced a physically observable far zone time domain field, this is not convenient to do directly in 2-D, since a convolution would be required. However, a representative 2-D far zone time domain result can be obtained directly. This result can then be transformed to the frequency domain using a Fast Fourier Transform, corrected with a simple multiplicative factor, and used, for example, to calculate the complex wideband scattering width of a target. If an actual time domain far zone result is required it can be obtained by inverse Fourier transform of the final frequency domain result.

  9. Zone-specific remodeling of tumor blood vessels affects tumor growth.

    PubMed

    Tilki, Derya; Kilic, Nerbil; Sevinc, Sema; Zywietz, Friedrich; Stief, Christian G; Ergun, Suleyman

    2007-11-15

    Chaotic organization, abnormal leakiness, and structural instability are characteristics of tumor vessels. However, morphologic events of vascular remodeling in relation to tumor growth are not sufficiently studied yet. By using the rat rhabdomyosarcoma tumor model vascular morphogenesis was studied by light and electron microscopy and immunohistochemistry in relation to tumor regions such as tumor surrounding (TSZ), marginal (TMZ), intermediate (TIZ), and center (TCZ) zones. The analyses revealed that blood vessels of TSZ display a regular ultrastructure, whereas blood vessels of TMZ showed a chaotic organization and unstable structure with a diffuse or even lacking basal lamina, and missing or irregular assembled periendothelial cells. In contrast, blood vessels of TIZ and TCZ exhibited a more or less stabilized vessel structure with increased diameter. Correspondingly, normal assembly of alpha-smooth-muscle-actin (alpha-SMA)-positive cells into the vessel wall was observed in blood vessels of TSZ, TIZ, and TCZ. Also, Ang1 immunostaining was strongest in large vessels of TIZ and TCZ, whereas Ang2 staining was prominent in small vessels of TIZ. Tie2 staining was detectable in small and large vessels of all tumor zones. Immunostaining for alpha(v)beta(3)-integrin was strongest in small vessels of TMZ, whereas large vessels of TIZ and TCZ were almost negative. The results indicate a zone-specific remodeling of tumor blood vessels by stabilization of vessels in TIZ and TCZ, whereas small vessels of these zones obviously undergo regression leading to tumor necrosis. Thus, a better understanding of vascular remodeling and stabilization in tumors would enable new strategies in tumor therapy and imaging. (c) 2007 American Cancer Society.

  10. The role of the distal elongation zone in the response of maize roots to auxin and gravity

    NASA Technical Reports Server (NTRS)

    Ishikawa, H.; Evans, M. L.

    1993-01-01

    We used a video digitizer system to (a) measure changes in the pattern of longitudinal surface extension in primary roots of maize (Zea mays L.) upon application and withdrawal of auxin and (b) compare these patterns during gravitropism in control roots and roots pretreated with auxin. Special attention was paid to the distal elongation zone (DEZ), arbitrarily defined as the region between the meristem and the point within the elongation zone at which the rate of elongation reaches 0.3 of the peak rate. For roots in aqueous solution, the basal limit of the DEZ is about 2.5 mm behind the tip of the root cap. Auxin suppressed elongation throughout the elongation zone, but, after 1 to 3 h, elongation resumed, primarily as a result of induction of rapid elongation in the DEZ. Withdrawal of auxin during the period of strong inhibition resulted in exceptionally rapid elongation attributable to the initiation of rapid elongation in the DEZ plus recovery in the main elongation zone. Gravistimulation of auxin-inhibited roots induced rapid elongation in the DEZ along the top of the root. This resulted in rapid gravitropism even though the elongation rate of the root was zero before gravistimulation. The results indicate that cells of the DEZ differ from cells in the bulk of the elongation zone with respect to auxin sensitivity and that DEZ cells play an important role in gravitropism.

  11. 77 FR 6007 - Quarterly Listings; Safety Zones, Security Zones, Special Local Regulations, Drawbridge Operation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-07

    ...] Quarterly Listings; Safety Zones, Security Zones, Special Local Regulations, Drawbridge Operation... they could be published in the Federal Register. This notice lists temporary safety zones, security zones, special local regulations, drawbridge operation regulations and regulated navigation areas, all...

  12. Radiant zone heated particulate filter

    DOEpatents

    Gonze, Eugene V [Pinckney, MI

    2011-12-27

    A system includes a particulate matter (PM) filter including an upstream end for receiving exhaust gas and a downstream end. A radiant zoned heater includes N zones, where N is an integer greater than one, wherein each of the N zones includes M sub-zones, where M is an integer greater than or equal to one. A control module selectively activates at least a selected one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones, restricts exhaust gas flow in a portion of the PM filter that corresponds to the selected one of the N zones, and deactivates non-selected ones of the N zones.

  13. Habitable Zone Evolution

    NASA Astrophysics Data System (ADS)

    Waltham, D.; Lota, J.

    2012-12-01

    The location of the habitable zone around a star depends upon stellar luminosity and upon the properties of a potentially habitable planet such as its mass and near-surface volatile inventory. Stellar luminosity generally increases as a star ages whilst planetary properties change through time as a consequence of biological and geological evolution. Hence, the location of the habitable zone changes through time as a result of both stellar evolution and planetary evolution. Using the Earth's Phanerozoic temperature history as a constraint, it is shown that changes in our own habitable zone over the last 540 My have been dominated by planetary evolution rather than solar evolution. Furthermore, sparse data from earlier times suggests that planetary evolution may have dominated habitable zone development throughout our biosphere's history. Hence, the existence of a continuously habitable zone depends upon accidents of complex bio-geochemical evolution more than it does upon relatively simple stellar-evolution. Evolution of the inner margin of the habitable zone through time using three different estimates for climate sensitivity. The dashed line shows a typical predicted evolution assuming this was driven simply by a steady increase in solar luminosity. Solar evolution does not account for the observations. Evolution of the outer margin of the habitable zone through time using three different estimates for climate sensitivity. The dashed line shows a typical predicted evolution assuming this was driven simply by a steady increase in solar luminosity. Solar evolution does not account for the observations.

  14. High CHMP4B expression is associated with accelerated cell proliferation and resistance to doxorubicin in hepatocellular carcinoma.

    PubMed

    Hu, Baoying; Jiang, Dawei; Chen, Yuyan; Wei, Lixian; Zhang, Shusen; Zhao, Fengbo; Ni, Runzhou; Lu, Cuihua; Wan, Chunhua

    2015-04-01

    Charged multivesicular body protein 4B (CHMP4B), a subunit of the endosomal sorting complex required for transport (ESCRT)-III complex, plays an important part in cytokinetic membrane abscission and the late stage of mitotic cell division. In this study, we explored the prognostic significance of CHMP4B in human hepatocellular carcinoma (HCC) and its impact on the physiology of HCC cells. Western blot and immunohistochemistrical analyses showed that CHMP4B was significantly upregulated in HCC tissues, compared with adjacent non-tumorous tissues. Meanwhile, clinicopathological analysis revealed that high CHMP4B expression was correlated with multiple clinicopathological variables, including AFP, cirrhosis, AJCC stage, Ki-67 expression, and poor prognosis. More importantly, univariate and multivariate survival analyses demonstrated that CHMP4B served as an independent prognostic factor for survival of HCC patients. Using HCC cell cultures, we found that the expression of CHMP4B was progressively upregulated after the release from serum starvation. To verify whether CHMP4B could regulate the proliferation of HCC cells, CHMP4B was knocked down through the transfection of CHMP4B-siRNA oligos. Flow cytometry and CCK-8 assays indicated that interference of CHMP4B led to cell cycle arrest and proliferative impairment of HCC cells. Additionally, depletion of CHMP4B expression could increase the sensitivity to doxorubicin in HepG2 and Huh7 cells. Taken together, our results implied that CHMP4B could be a promising prognostic biomarker as well as a potential therapeutic target of HCC.

  15. Fibonacci-like zone plate

    NASA Astrophysics Data System (ADS)

    Cheng, Shubo; Liu, Mengsi; Xia, Tian; Tao, Shaohua

    2018-06-01

    We present a new family of diffractive lenses, Fibonacci-like zone plates, generated with a modified Fibonacci sequence. The focusing properties and the evolution of transverse diffraction pattern for the Fibonacci-like zone plates have been analytically investigated both theoretically and experimentally and compared with the corresponding Fresnel zone plates of the same resolution. The results demonstrate that the Fibonacci-like zone plates possess the self-similar property and the multifocal behavior. Furthermore, the Fibonacci-like zone plate beams are found to possess the self-reconstruction property, and would be promising for 3D optical tweezers, laser machining, and optical imaging.

  16. 76 FR 70342 - Quarterly Listings; Safety Zones, Security Zones, Special Local Regulations, Drawbridge Operation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-14

    ...] Quarterly Listings; Safety Zones, Security Zones, Special Local Regulations, Drawbridge Operation... published in the Federal Register. This notice lists temporary safety zones, security zones, special local..., telephone (202) 372-3862. For questions on viewing, or on submitting material to the docket, contact Ms...

  17. Physical Controls on Biogeochemical Processes in Intertidal Zones of Beach Aquifers

    NASA Astrophysics Data System (ADS)

    Heiss, James W.; Post, Vincent E. A.; Laattoe, Tariq; Russoniello, Christopher J.; Michael, Holly A.

    2017-11-01

    Marine ecosystems are sensitive to inputs of chemicals from submarine groundwater discharge. Tidally influenced saltwater-freshwater mixing zones in beach aquifers can host biogeochemical transformations that modify chemical loads prior to discharge. A numerical variable-density groundwater flow and reactive transport model was used to evaluate the physical controls on reactivity for mixing-dependent and mixing-independent reactions in beach aquifers, represented as denitrification and sulfate reduction, respectively. A sensitivity analysis was performed across typical values of tidal amplitude, hydraulic conductivity, terrestrial freshwater flux, beach slope, dispersivity, and DOC reactivity. For the model setup and conditions tested, the simulations demonstrate that denitrification can remove up to 100% of terrestrially derived nitrate, and sulfate reduction can transform up to 8% of seawater-derived sulfate prior to discharge. Tidally driven mixing between saltwater and freshwater promotes denitrification along the boundary of the intertidal saltwater circulation cell in pore water between 1 and 10 ppt. The denitrification zone occupies on average 49% of the mixing zone. Denitrification rates are highest on the landward side of the circulation cell and decrease along circulating flow paths. Reactivity for mixing-dependent reactions increases with the size of the mixing zone and solute supply, while mixing-independent reactivity is controlled primarily by solute supply. The results provide insights into the types of beaches most efficient in altering fluxes of chemicals prior to discharge and could be built upon to help engineer beaches to enhance reactivity. The findings have implications for management to protect coastal ecosystems and the estimation of chemical fluxes to the ocean.

  18. Selinexor Plus Combination Chemotherapy in Treating Patients With Advanced B Cell Non-Hodgkin Lymphoma

    ClinicalTrials.gov

    2018-02-12

    Diffuse Large B-Cell Lymphoma; Recurrent B-Cell Non-Hodgkin Lymphoma; Recurrent Extranodal Marginal Zone Lymphoma; Recurrent Follicular Lymphoma; Recurrent Indolent Adult Non-Hodgkin Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Waldenstrom Macroglobulinemia; Refractory B-Cell Non-Hodgkin Lymphoma; Refractory Extranodal Marginal Zone Lymphoma; Refractory Follicular Lymphoma; Refractory Mantle Cell Lymphoma; Stage III Non-Hodgkin Lymphoma; Stage IV Non-Hodgkin Lymphoma; Transformed Recurrent Non-Hodgkin Lymphoma

  19. Cascadia Subduction Zone

    USGS Publications Warehouse

    Frankel, Arthur D.; Petersen, Mark D.

    2008-01-01

    The geometry and recurrence times of large earthquakes associated with the Cascadia Subduction Zone (CSZ) were discussed and debated at a March 28-29, 2006 Pacific Northwest workshop for the USGS National Seismic Hazard Maps. The CSZ is modeled from Cape Mendocino in California to Vancouver Island in British Columbia. We include the same geometry and weighting scheme as was used in the 2002 model (Frankel and others, 2002) based on thermal constraints (Fig. 1; Fluck and others, 1997 and a reexamination by Wang et al., 2003, Fig. 11, eastern edge of intermediate shading). This scheme includes four possibilities for the lower (eastern) limit of seismic rupture: the base of elastic zone (weight 0.1), the base of transition zone (weight 0.2), the midpoint of the transition zone (weight 0.2), and a model with a long north-south segment at 123.8? W in the southern and central portions of the CSZ, with a dogleg to the northwest in the northern portion of the zone (weight 0.5). The latter model was derived from the approximate average longitude of the contour of the 30 km depth of the CSZ as modeled by Fluck et al. (1997). A global study of the maximum depth of thrust earthquakes on subduction zones by Tichelaar and Ruff (1993) indicated maximum depths of about 40 km for most of the subduction zones studied, although the Mexican subduction zone had a maximum depth of about 25 km (R. LaForge, pers. comm., 2006). The recent inversion of GPS data by McCaffrey et al. (2007) shows a significant amount of coupling (a coupling factor of 0.2-0.3) as far east as 123.8? West in some portions of the CSZ. Both of these lines of evidence lend support to the model with a north-south segment at 123.8? W.

  20. Diffusion chamber system for testing of collagen-based cell migration barriers for separation of ligament enthesis zones in tissue-engineered ACL constructs.

    PubMed

    Hahner, J; Hoyer, M; Hillig, S; Schulze-Tanzil, G; Meyer, M; Schröpfer, M; Lohan, A; Garbe, L-A; Heinrich, G; Breier, A

    2015-01-01

    A temporary barrier separating scaffold zones seeded with different cell types prevents faster growing cells from overgrowing co-cultured cells within the same construct. This barrier should allow sufficient nutrient diffusion through the scaffold. The aim of this study was to test the effect of two variants of collagen-based barriers on macromolecule diffusion, viability, and the spreading efficiency of primary ligament cells on embroidered scaffolds. Two collagen barriers, a thread consisting of a twisted film tape and a sponge, were integrated into embroidered poly(lactic-co-caprolactone) and polypropylene scaffolds, which had the dimension of lapine anterior cruciate ligaments (ACL). A diffusion chamber system was designed and established to monitor nutrient diffusion using fluorescein isothiocyanate-labeled dextran of different molecular weights (20, 40, 150, 500 kDa). Vitality of primary lapine ACL cells was tested at days 7 and 14 after seeding using fluorescein diacetate and ethidium bromide staining. Cell spreading on the scaffold surface was measured using histomorphometry. Nuclei staining of the cross-sectioned scaffolds revealed the penetration of ligament cells through both barrier types. The diffusion chamber was suitable to characterize the diffusivity of dextran molecules through embroidered scaffolds with or without integrated collagen barriers. The diffusion coefficients were generally significantly lower in scaffolds with barriers compared to those without barriers. No significant differences between diffusion coefficients of both barrier types were detected. Both barriers were cyto-compatible and prevented most of the ACL cells from crossing the barrier, whereby the collagen thread was easier to handle and allowed a higher rate of cell spreading.

  1. Donor Peripheral Stem Cell Transplant in Treating Patients With Hematolymphoid Malignancies

    ClinicalTrials.gov

    2016-11-17

    Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Adult Nasal Type Extranodal NK/T-cell Lymphoma; Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma; Hepatosplenic T-cell Lymphoma; Intraocular Lymphoma; Nodal Marginal Zone B-cell Lymphoma; Peripheral T-cell Lymphoma; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Adult T-cell Leukemia/Lymphoma; Recurrent Cutaneous T-cell Non-Hodgkin Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Mycosis Fungoides/Sezary Syndrome; Recurrent Small Lymphocytic Lymphoma; Refractory Chronic Lymphocytic Leukemia; Relapsing Chronic Myelogenous Leukemia; Splenic Marginal Zone Lymphoma; Waldenstrom Macroglobulinemia

  2. 76 FR 38297 - Safety Zone; Marine Events Requiring Safety Zones in the Captain of the Port Sault Sainte Marie Zone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-30

    ...'' W [DATUM: NAD 83]. (ii) Enforcement Period. This safety zone will be enforced on July 4, 2011 from 9...'' N, 086[deg]39'08.52'' W [DATUM: NAD 83]. (ii) Enforcement Period. This safety zone will be enforced...: NAD 83], with the West Bay shoreline forming the South and West boundaries of the zone. (ii...

  3. Spatial distributions of biogeochemical reactions in freshwater-saltwater mixing zones of sandy beach aquifers

    NASA Astrophysics Data System (ADS)

    Kim, K. H.; Michael, H. A.; Ullman, W. J.; Cai, W. J.

    2017-12-01

    Beach aquifers host biogeochemically dynamic mixing zones between fresh and saline groundwaters of contrasting origins, histories, and compositions. Seawater, driven up the beachface by waves and tides, infiltrates into the sand and meets the seaward-discharging fresh groundwater, creating and maintaining a highly reactive intertidal circulation cell well-defined by salinity. Seawater supplies oxygen and reactive carbon to the circulation cell, supporting biogeochemical reactions within the cell that transform and attenuate dissolved nutrient fluxes from terrestrial sources. We investigated the spatial distribution of chemical reaction zones within the intertidal circulation cell at Cape Shores, Lewes, Delaware. Porewater samples were collected from multi-level wells along a beach-perpendicular transect. Samples were analyzed for particulate carbon and reactive solutes, and incubated to obtain rates of oxic respiration and denitrification. High rates of oxic respiration were observed higher on the beach, in the landward freshwater-saline water mixing zone, where dissolved oxygen availability was high. Denitrification was dominant in lower areas of the beach, below the intertidal discharge point. High respiration rates did not correlate with particulate carbon concentrations entrained within porewater, suggesting that dissolved organic carbon or immobile particulate carbon trapped within the sediment can contribute to and alter bulk reactivity. A better understanding of the sources and sinks of carbon within the beach will improve our ability to predict nutrient fluxes to estuaries and oceans, aiding the management of coastal environments and ecosystems.

  4. Marginal zone lymphoma-derived interfollicular diffuse large B-cell lymphoma harboring 20q12 chromosomal deletion and missense mutation of BIRC3 gene: a case report.

    PubMed

    Hatem, Joseph; Schrank-Hacker, April M; Watt, Christopher D; Morrissette, Jennifer J D; Rubin, Adam I; Kim, Ellen J; Nasta, Sunita D; Wasik, Mariusz A; Bogusz, Agata M

    2016-12-19

    Diffuse large B-cell lymphoma (DLBCL) typically leads to effacement of the nodal architecture by an infiltrate of malignant cells. Rarely (<1%), DLBCL can present with an interfollicular pattern (DLBCL-IF) preserving the lymphoid follicles. It has been postulated that DLBCL-IF is derived from marginal zone B cells and may represent a large-cell transformation of marginal zone lymphoma (MZL), however no direct evidence has been provided to date. Here we describe a rare case of a diagnostically challenging DLBCL-IF involving a lymph node in a patient with a prior history of lymphadenopathy for several years and MZL involving skin. A 53-year old man presented to our Dermatology Clinic due to a 1-year history of generalized itching, fatigue of 2-3 month's duration, nausea and mid back rash that was biopsied. PET (positron emission tomography)/CT (computed tomography) was performed and revealed inguinal, pelvic, retroperitoneal, axillary, and cervical lymphadenopathy. The patient was referred to surgery for excisional biopsy of a right inguinal lymph node. Diagnostic H&E stained slides and ancillary studies were reviewed for the lymph node and skin specimens. B-cell clonality by PCR and sequencing studies were performed on both specimens. We demonstrate that this patient's MZL and DLBCL-IF are clonally related, strongly suggesting that transformation of MZL to DLBCL had occurred. Furthermore, we identified a novel deletion of the long arm of chromosome 20 (del(20q12)) and a missense mutation in BIRC3 (Baculoviral IAP repeat-containing protein 3) in this patient's DLBCL that are absent from his MZL, suggesting that these genetic alterations contributed to the large cell transformation. To our knowledge, this is the first report providing molecular evidence for a previously suspected link between MZL and DLBCL-IF. In addition, we describe for the first time del(20q12) and a missense mutation in BIRC3 in DLBCL. Our findings also raise awareness of DLBCL-IF and discuss the

  5. Rituximab, Romidepsin, and Lenalidomide in Treating Patients With Recurrent or Refractory B-cell Non-Hodgkin Lymphoma

    ClinicalTrials.gov

    2016-08-09

    B-cell Adult Acute Lymphoblastic Leukemia; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Intraocular Lymphoma; Nodal Marginal Zone B-cell Lymphoma; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Small Lymphocytic Lymphoma; Refractory Hairy Cell Leukemia; Small Intestine Lymphoma; Splenic Marginal Zone Lymphoma; Testicular Lymphoma; Waldenström Macroglobulinemia

  6. A study of the mutational landscape of pediatric-type follicular lymphoma and pediatric nodal marginal zone lymphoma.

    PubMed

    Ozawa, Michael G; Bhaduri, Aparna; Chisholm, Karen M; Baker, Steven A; Ma, Lisa; Zehnder, James L; Luna-Fineman, Sandra; Link, Michael P; Merker, Jason D; Arber, Daniel A; Ohgami, Robert S

    2016-10-01

    Pediatric-type follicular lymphoma and pediatric marginal zone lymphoma are two of the rarest B-cell lymphomas. These lymphomas occur predominantly in the pediatric population and show features distinct from their more common counterparts in adults: adult-type follicular lymphoma and adult-type nodal marginal zone lymphoma. Here we report a detailed whole-exome deep sequencing analysis of a cohort of pediatric-type follicular lymphomas and pediatric marginal zone lymphomas. This analysis revealed a recurrent somatic variant encoding p.Lys66Arg in the transcription factor interferon regulatory factor 8 (IRF8) in 3 of 6 cases (50%) of pediatric-type follicular lymphoma. This specific point mutation was not detected in pediatric marginal zone lymphoma or in adult-type follicular lymphoma. Additional somatic point mutations in pediatric-type follicular lymphoma were observed in genes involved in transcription, intracellular signaling, and cell proliferation. In pediatric marginal zone lymphoma, no recurrent mutation was identified; however, somatic point mutations were observed in genes involved in cellular adhesion, cytokine regulatory elements, and cellular proliferation. A somatic variant in AMOTL1, a recurrently mutated gene in splenic marginal zone lymphoma, was also identified in a case of pediatric marginal zone lymphoma. The overall non-synonymous mutational burden was low in both pediatric-type follicular lymphoma and pediatric marginal zone lymphoma (4.6 mutations per exome). Altogether, these findings support a distinctive genetic basis for pediatric-type follicular lymphoma and pediatric marginal zone lymphoma when compared with adult subtypes and to one another. Moreover, identification of a recurrent point mutation in IRF8 provides insight into a potential driver mutation in the pathogenesis of pediatric-type follicular lymphoma with implications for novel diagnostic or therapeutic strategies.

  7. A study of the mutational landscape of pediatric-type follicular lymphoma and pediatric nodal marginal zone lymphoma

    PubMed Central

    Ozawa, Michael G; Bhaduri, Aparna; Chisholm, Karen M; Baker, Steven A; Ma, Lisa; Zehnder, James L; Luna-Fineman, Sandra; Link, Michael P; Merker, Jason D; Arber, Daniel A; Ohgami, Robert S

    2016-01-01

    Pediatric-type follicular lymphoma and pediatric marginal zone lymphoma are two of the rarest B-cell lymphomas. These lymphomas occur predominantly in the pediatric population and show features distinct from their more common counterparts in adults: adult-type follicular lymphoma and adult-type nodal marginal zone lymphoma. Here we report a detailed whole-exome deep sequencing analysis of a cohort of pediatric-type follicular lymphomas and pediatric marginal zone lymphomas. This analysis revealed a recurrent somatic variant encoding p.Lys66Arg in the transcription factor interferon regulatory factor 8 (IRF8) in 3 of 6 cases (50%) of pediatric-type follicular lymphoma. This specific point mutation was not detected in pediatric marginal zone lymphoma or in adult-type follicular lymphoma. Additional somatic point mutations in pediatric-type follicular lymphoma were observed in genes involved in transcription, intracellular signaling, and cell proliferation. In pediatric marginal zone lymphoma, no recurrent mutation was identified; however, somatic point mutations were observed in genes involved in cellular adhesion, cytokine regulatory elements, and cellular proliferation. A somatic variant in AMOTL1, a recurrently mutated gene in splenic marginal zone lymphoma, was also identified in a case of pediatric marginal zone lymphoma. The overall non-synonymous mutational burden was low in both pediatric-type follicular lymphoma and pediatric marginal zone lymphoma (4.6 mutations per exome). Altogether, these findings support a distinctive genetic basis for pediatric-type follicular lymphoma and pediatric marginal zone lymphoma when compared with adult subtypes and to one another. Moreover, identification of a recurrent point mutation in IRF8 provides insight into a potential driver mutation in the pathogenesis of pediatric-type follicular lymphoma with implications for novel diagnostic or therapeutic strategies. PMID:27338637

  8. 76 FR 44803 - Quarterly Listings; Safety Zones, Security Zones, Special Local Regulations, Drawbridge Operation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-27

    ... USCG-2009-1081 New Orleans, LA Safety Zone (Part 165)..... 12/23/2009 USCG-2009-1084 Rio Vista, CA...-1096 Port Portland Zone......... Safety Zone (Part 165)..... 7/3/2010 USCG-2009-0040 La Push, WA Safety...-0950 Madisonville, LA Safety Zone (Part 165)..... 12/31/2009 USCG-2009-0951 Lower Mississippi River...

  9. CCI-779 in Treating Patients With Recurrent or Refractory B-Cell Non-Hodgkin's Lymphoma or Chronic Lymphocytic Leukemia

    ClinicalTrials.gov

    2014-05-07

    B-cell Chronic Lymphocytic Leukemia; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Malignant Neoplasm; Nodal Marginal Zone B-cell Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Small Lymphocytic Lymphoma; Refractory Chronic Lymphocytic Leukemia; Splenic Marginal Zone Lymphoma; Waldenström Macroglobulinemia

  10. Monoclonal Antibody Therapy and Peripheral Stem Cell Transplant in Treating Patients With Non-Hodgkin's Lymphoma

    ClinicalTrials.gov

    2013-01-08

    Contiguous Stage II Adult Diffuse Large Cell Lymphoma; Contiguous Stage II Adult Diffuse Small Cleaved Cell Lymphoma; Contiguous Stage II Grade 1 Follicular Lymphoma; Contiguous Stage II Grade 2 Follicular Lymphoma; Contiguous Stage II Grade 3 Follicular Lymphoma; Contiguous Stage II Mantle Cell Lymphoma; Contiguous Stage II Marginal Zone Lymphoma; Contiguous Stage II Small Lymphocytic Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Noncontiguous Stage II Adult Diffuse Large Cell Lymphoma; Noncontiguous Stage II Adult Diffuse Small Cleaved Cell Lymphoma; Noncontiguous Stage II Grade 1 Follicular Lymphoma; Noncontiguous Stage II Grade 2 Follicular Lymphoma; Noncontiguous Stage II Grade 3 Follicular Lymphoma; Noncontiguous Stage II Mantle Cell Lymphoma; Noncontiguous Stage II Marginal Zone Lymphoma; Noncontiguous Stage II Small Lymphocytic Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Small Lymphocytic Lymphoma; Stage I Adult Diffuse Large Cell Lymphoma; Stage I Adult Diffuse Small Cleaved Cell Lymphoma; Stage I Grade 1 Follicular Lymphoma; Stage I Grade 2 Follicular Lymphoma; Stage I Grade 3 Follicular Lymphoma; Stage I Mantle Cell Lymphoma; Stage I Marginal Zone Lymphoma; Stage I Small Lymphocytic Lymphoma; Stage III Adult Diffuse Large Cell Lymphoma; Stage III Adult Diffuse Small Cleaved Cell Lymphoma; Stage III Grade 1 Follicular Lymphoma; Stage III Grade 2 Follicular Lymphoma; Stage III Grade 3 Follicular Lymphoma; Stage III Mantle Cell Lymphoma; Stage III Marginal Zone Lymphoma; Stage III Small Lymphocytic Lymphoma; Stage IV Adult Diffuse Large Cell Lymphoma; Stage IV Adult Diffuse Small Cleaved Cell Lymphoma; Stage IV Grade 1 Follicular Lymphoma; Stage IV Grade 2

  11. MAPK1 is required for establishing the pattern of cell proliferation and for cell survival during lens development

    PubMed Central

    Upadhya, Dinesh; Ogata, Masato; Reneker, Lixing W.

    2013-01-01

    The mitogen-activated protein kinases (MAPKs; also known as ERKs) are key intracellular signaling molecules that are ubiquitously expressed in tissues and were assumed to be functionally equivalent. Here, we use the mouse lens as a model system to investigate whether MAPK1 plays a specific role during development. MAPK3 is known to be dispensable for lens development. We demonstrate that, although MAPK1 is uniformly expressed in the lens epithelium, its deletion significantly reduces cell proliferation in the peripheral region, an area referred to as the lens germinative zone in which most active cell division occurs during normal lens development. By contrast, cell proliferation in the central region is minimally affected by MAPK1 deletion. Cell cycle regulators, including cyclin D1 and survivin, are downregulated in the germinative zone of the MAPK1-deficient lens. Interestingly, loss of MAPK1 subsequently induces upregulation of phosphorylated MAPK3 (pMAPK3) levels in the lens epithelium; however, this increase in pMAPK3 is not sufficient to restore cell proliferation in the germinative zone. Additionally, MAPK1 plays an essential role in epithelial cell survival but is dispensable for fiber cell differentiation during lens development. Our data indicate that MAPK1/3 control cell proliferation in the lens epithelium in a spatially defined manner; MAPK1 plays a unique role in establishing the highly mitotic zone in the peripheral region, whereas the two MAPKs share a redundant role in controlling cell proliferation in the central region of the lens epithelium. PMID:23482492

  12. Shear zones bounding the central zone of the Limpopo Mobile Belt, southern Africa

    NASA Astrophysics Data System (ADS)

    McCouri, Stephen; Vearncombe, Julian R.

    Contrary to previously suggested north-directed thrust emplacement of the central zone of the Limpopo mobile belt, we present evidence indicating west-directed emplacement. The central zone differs from the marginal zones in rock types, structural style and isotopic signature and is an allochthonous thrust sheet. It is bounded in the north by the dextral Tuli-Sabi shear zone and in the south by the sinistral Palala shear zone which are crustal-scale lateral ramps. Published gravity data suggest that the lateral ramps are linked at depth and they probably link at the surface, in a convex westward frontal ramp, in the vicinity of longitude 26°30'E in eastern Botswana. Two phases of movement, the first between 2.7 and 2.6 Ga and the second between 2.0 and 1.8 Ga. occurred on both the Tuli-Sabi and the Palala shear zones.

  13. Freeway work zone lane capacity.

    DOT National Transportation Integrated Search

    2009-01-01

    The focus of this report is a capacity analysis of two long-term urban freeway Work Zones. Work Zone #1 : tapered four mainline lanes to two, using two separate tapers; Work Zone #2 tapered two mainline lanes to one. : Work Zone throughput was analyz...

  14. Bryostatin 1 Plus Vincristine in Treating Patients With Progressive or Relapsed Non-Hodgkin's Lymphoma After Bone Marrow or Stem Cell Transplantation

    ClinicalTrials.gov

    2013-01-09

    Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Nodal Marginal Zone B-cell Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Small Lymphocytic Lymphoma; Splenic Marginal Zone Lymphoma

  15. Long-term hydrocephalus alters the cytoarchitecture of the adult subventricular zone

    PubMed Central

    Campos-Ordoñez, Tania; Herranz-Pérez, Vicente; Chaichana, Kaisorn L.; Rincon-Torroella, Jordina; Rigamonti, Daniele; García-Verdugo, Jose M.; Quiñones-Hinojosa, Alfredo; Gonzalez-Perez, Oscar

    2014-01-01

    Hydrocephalus can develop secondarily to a disturbance in production, flow and/or absorption of cerebrospinal fluid. Experimental models of hydrocephalus, especially subacute and chronic hydrocephalus, are few and limited, and the effects of hydrocephalus on the subventricular zone are unclear. The aim of this study was to analyze the effects of long-term obstructive hydrocephalus on the subventricular zone, which is the neurogenic niche lining the lateral ventricles. We developed a new method to induce hydrocephalus by obstructing the aqueduct of Sylvius in the mouse brain, thus simulating aqueductal stenosis in humans. In 120-day-old rodents (n = 18 per group), the degree of ventricular dilatation and cellular composition of the subventricular zone were studied by immunofluorescence and transmission electron microscopy. In adult patients (age > 18 years), the sizes of the subventricular zone, corpus callosum, and internal capsule were analyzed by magnetic resonance images obtained from patients with and without aqueductal stenosis (n=25 per group). Mice with 60-day hydrocephalus had a reduced number of Ki67+ and doublecortin+ cells on immunofluorescence, as well as decreased number of neural progenitors and neuroblasts in the subventricular zone on electron microscopy analysis as compared to non-hydrocephalic mice. Remarkably, a number of extracellular matrix structures (fractones) contacting the ventricular lumen and blood vessels were also observed around the subventricular zone in mice with hydrocephalus. In humans, the widths of the subventricular zone, corpus callosum, and internal capsule in patients with aqueductal stenosis were significantly smaller than age and gender-matched patients without aqueductal stenosis. In summary, supratentorial hydrocephalus reduces the proliferation rate of neural progenitors and modifies the cytoarchitecture and extracellular matrix compounds of the subventricular zone. In humans, this similar process reduces the

  16. Long-term hydrocephalus alters the cytoarchitecture of the adult subventricular zone.

    PubMed

    Campos-Ordoñez, Tania; Herranz-Pérez, Vicente; Chaichana, Kaisorn L; Rincon-Torroella, Jordina; Rigamonti, Daniele; García-Verdugo, Jose M; Quiñones-Hinojosa, Alfredo; Gonzalez-Perez, Oscar

    2014-11-01

    Hydrocephalus can develop secondarily to a disturbance in production, flow and/or absorption of cerebrospinal fluid. Experimental models of hydrocephalus, especially subacute and chronic hydrocephalus, are few and limited, and the effects of hydrocephalus on the subventricular zone are unclear. The aim of this study was to analyze the effects of long-term obstructive hydrocephalus on the subventricular zone, which is the neurogenic niche lining the lateral ventricles. We developed a new method to induce hydrocephalus by obstructing the aqueduct of Sylvius in the mouse brain, thus simulating aqueductal stenosis in humans. In 120-day-old rodents (n=18 per group), the degree of ventricular dilatation and cellular composition of the subventricular zone were studied by immunofluorescence and transmission electron microscopy. In adult patients (age>18years), the sizes of the subventricular zone, corpus callosum, and internal capsule were analyzed by magnetic resonance images obtained from patients with and without aqueductal stenosis (n=25 per group). Mice with 60-day hydrocephalus had a reduced number of Ki67+ and doublecortin+cells on immunofluorescence, as well as decreased number of neural progenitors and neuroblasts in the subventricular zone on electron microscopy analysis as compared to non-hydrocephalic mice. Remarkably, a number of extracellular matrix structures (fractones) contacting the ventricular lumen and blood vessels were also observed around the subventricular zone in mice with hydrocephalus. In humans, the widths of the subventricular zone, corpus callosum, and internal capsule in patients with aqueductal stenosis were significantly smaller than age and gender-matched patients without aqueductal stenosis. In summary, supratentorial hydrocephalus reduces the proliferation rate of neural progenitors and modifies the cytoarchitecture and extracellular matrix compounds of the subventricular zone. In humans, this similar process reduces the subventricular

  17. Early history of subplate and interstitial neurons: from Theodor Meynert (1867) to the discovery of the subplate zone (1974)

    PubMed Central

    Judaš, Miloš; Sedmak, Goran; Pletikos, Mihovil

    2010-01-01

    In this historical review, we trace the early history of research on the fetal subplate zone, subplate neurons and interstitial neurons in the white matter of the adult nervous system. We arrive at several general conclusions. First, a century of research clearly testifies that interstitial neurons, subplate neurons and the subplate zone were first observed and variously described in the human brain – or, in more general terms, in large brains of gyrencephalic mammals, characterized by an abundant white matter and slow and protracted prenatal and postnatal development. Secondly, the subplate zone cannot be meaningfully defined using a single criterion – be it a specific population of cells, fibres or a specific molecular or genetic marker. The subplate zone is a highly dynamic architectonic compartment and its size and cellular composition do not remain constant during development. Thirdly, it is important to make a clear distinction between the subplate zone and the subplate (and interstitial) neurons. The transient existence of the subplate zone (as a specific architectonic compartment of the fetal telencephalic wall) should not be equated with the putative transient existence of subplate neurons. It is clear that in rodents, and to an even greater extent in humans and monkeys, a significant number of subplate cells survive and remain functional throughout life. PMID:20979585

  18. 33 CFR 165.503 - Security Zone; Captain of the Port Hampton Roads Zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Port Hampton Roads Zone. 165.503 Section 165.503 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED... § 165.503 Security Zone; Captain of the Port Hampton Roads Zone. (a) Definitions. As used in this...

  19. A Phase 2 Study of Concurrent Fludarabine and Rituximab for the Treatment of Marginal Zone Lymphomas

    PubMed Central

    Brown, Jennifer R; Friedberg, Jonathan W.; Feng, Yang; Scofield, Sarah; Phillips, Kimberly; Cin, Paola Dal; Joyce, Robin; Takvorian, Ronald W; Fisher, David C; Fisher, Richard I; Liesveld, Jane; Marquis, Diana; Neuberg, Donna; Freedman, Arnold S

    2009-01-01

    SUMMARY The marginal zone lymphomas are a recently defined group of related diseases likely arising from a common cell of origin, the marginal zone B cell. Data on therapy for subtypes other than gastric MALT has been largely limited to retrospective case series. We therefore undertook this prospective phase 2 study of fludarabine and rituximab for the treatment of marginal zone lymphomas. 26 patients were enrolled, 14 with nodal MZL, 8 with MALT lymphomas and 4 with splenic MZL; 81% were receiving initial systemic therapy. Only 58% (95% CI 37–77%) of patients completed the planned six cycles, due to significant hematologic, infectious and allergic toxicity. Four late toxic deaths occurred due to infections (15% (95% CI 4.3–35%), two related to delayed bone marrow aplasia and two related to MDS. Nonetheless, the ORR was 85% (95% CI 65–96%), with 54% CRs. The progression-free survival at 3.1 years of follow-up is 79.5% (95% CI, 63–96%). We conclude that although concurrent fludarabine and rituximab given at this dose and schedule is a highly effective regimen in the treatment of marginal zone lymphomas, the significant hematologic and infectious toxicity observed both during and after therapy is prohibitive in this patient population, emphasizing the need to study marginal zone lymphomas as a separate entity. PMID:19344412

  20. In situ experimental study of subduction zone fluids using diamond anvil cells

    NASA Astrophysics Data System (ADS)

    Bureau, H.; Foy, E.; Somogyi, A.; Munsch, P.; Simon, G.; Kubsky, S.

    2008-12-01

    Experiments carried out in diamond anvil cells combined with in situ synchrotron light source measurements represent the only one issue to observe and study fluid equilibria in real time, at the pressure and temperature conditions of the subduction zones. We will present new results recently obtained at the DIFFABS beam line (SOLEIL Synchrotron) aiming at studying equilibria between silica-rich hydrous melts and aqueous fluids in the presence of U, Th, Pb, Ba and Br. We used synchrotron X-Ray fluorescence analysis performed in situ in Bassett-modified hydrothermal diamond anvil cells in order to monitor the chemical transfers of the studied elements between the phases in equilibrium at different pressures (up to 1.6 GPa) and temperatures (up to 900°C). We have calculated the partition coefficients for each studied element (i): Difluid/melt = Cifluid/Cimelt. Results show that U and Th exhibit more affinities for the silica-rich hydrous fluids in the presence or absence of Br, considered here such as an analogue for Cl, (i.e. 0.4 < DUfluid/melt < 0.7 depending on P,T conditions). Br partitioning shows that whereas this halogen element has very strong affinity to the aqueous fluid during magma degassing (DBrfluid/melt >> 10 after decompression) this coefficient decreases with pressure suggesting that Br would not be immediately washed out from the subducted plate during dehydration but may be recycled deeper in the mantle. These new data combined with previous ones obtained for Pb, Ba (Bureau et al., 2007, HPR vol 27, p. 235) and Rb, Sr, Zr (Bureau et al., 2004, Eos Trans. AGU, 85(47), V11C-05), allow us to propose a general outline of the fluid phase transfers through the subduction factory: (1) at shallow level: their nature and composition, the impact of the presence of halogens and the fertilizing role of such fluids in the mantle wedge, where the generation of arc magmas takes place (2) deeper in the mantle: where hydrous silica-rich supercritical fluids may

  1. 33 CFR 3.35-10 - Sector Miami Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Zone and Captain of the Port Zone. 3.35-10 Section 3.35-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL COAST GUARD AREAS, DISTRICTS, SECTORS, MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Seventh Coast Guard District § 3.35-10 Sector Miami Marine Inspection Zone and...

  2. 33 CFR 3.40-10 - Sector Mobile Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Zone and Captain of the Port Zone. 3.40-10 Section 3.40-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL COAST GUARD AREAS, DISTRICTS, SECTORS, MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Eighth Coast Guard District § 3.40-10 Sector Mobile Marine Inspection Zone and...

  3. 33 CFR 3.40-10 - Sector Mobile Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Zone and Captain of the Port Zone. 3.40-10 Section 3.40-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL COAST GUARD AREAS, DISTRICTS, SECTORS, MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Eighth Coast Guard District § 3.40-10 Sector Mobile Marine Inspection Zone and...

  4. 33 CFR 3.40-10 - Sector Mobile Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Zone and Captain of the Port Zone. 3.40-10 Section 3.40-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL COAST GUARD AREAS, DISTRICTS, SECTORS, MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Eighth Coast Guard District § 3.40-10 Sector Mobile Marine Inspection Zone and...

  5. 33 CFR 3.35-10 - Sector Miami Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Zone and Captain of the Port Zone. 3.35-10 Section 3.35-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL COAST GUARD AREAS, DISTRICTS, SECTORS, MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Seventh Coast Guard District § 3.35-10 Sector Miami Marine Inspection Zone and...

  6. 33 CFR 3.35-10 - Sector Miami Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Zone and Captain of the Port Zone. 3.35-10 Section 3.35-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL COAST GUARD AREAS, DISTRICTS, SECTORS, MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Seventh Coast Guard District § 3.35-10 Sector Miami Marine Inspection Zone and...

  7. 33 CFR 3.40-10 - Sector Mobile Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Zone and Captain of the Port Zone. 3.40-10 Section 3.40-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL COAST GUARD AREAS, DISTRICTS, SECTORS, MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Eighth Coast Guard District § 3.40-10 Sector Mobile Marine Inspection Zone and...

  8. 33 CFR 3.35-10 - Sector Miami Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Zone and Captain of the Port Zone. 3.35-10 Section 3.35-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL COAST GUARD AREAS, DISTRICTS, SECTORS, MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Seventh Coast Guard District § 3.35-10 Sector Miami Marine Inspection Zone and...

  9. 33 CFR 3.65-15 - Sector Portland Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Zone and Captain of the Port Zone. 3.65-15 Section 3.65-15 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL COAST GUARD AREAS, DISTRICTS, SECTORS, MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Thirteenth Coast Guard District § 3.65-15 Sector Portland Marine Inspection Zone...

  10. 33 CFR 3.35-10 - Sector Miami Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Zone and Captain of the Port Zone. 3.35-10 Section 3.35-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL COAST GUARD AREAS, DISTRICTS, SECTORS, MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Seventh Coast Guard District § 3.35-10 Sector Miami Marine Inspection Zone and...

  11. 33 CFR 3.40-10 - Sector Mobile Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Zone and Captain of the Port Zone. 3.40-10 Section 3.40-10 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL COAST GUARD AREAS, DISTRICTS, SECTORS, MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Eighth Coast Guard District § 3.40-10 Sector Mobile Marine Inspection Zone and...

  12. Mushy zone modeling

    NASA Astrophysics Data System (ADS)

    Glicksman, Martin E.; Smith, Richard N.; Marsh, Steven P.; Kuklinski, Robert

    A key element of mushy zone modeling is the description of the microscopic evolution of the lengthscales within the mushy zone and the influence of macroscopic transport processes. This paper describes some recent progress in developing a mean-field statistical theory of phase coarsening in adiabatic mushy zones. The main theoretical predictions are temporal scaling laws that indicate that average lengthscale increases as time 1/3, a self-similar distribution of mushy zone lengthscales based on spherical solid particle shapes, and kinetic rate constants which provide the dependences of the coarsening process on material parameters and the volume fraction of the solid phase. High precision thermal decay experiments are described which verify aspects of the theory in pure material mushy zones held under adiabatic conditions. The microscopic coarsening theory is then integrated within a macroscopic heat transfer model of one-dimensional alloy solidification, using the Double Integral Method. The method demonstrates an ability to predict the influence of macroscopic heat transfer on the evolution of primary and secondary dendrite arm spacings in Al-Cu alloys. Finally, some suggestions are made for future experimental and theoretical studies required in developing comprehensive solidification processing models.

  13. 47 CFR 73.609 - Zones.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 4 2014-10-01 2014-10-01 false Zones. 73.609 Section 73.609 Telecommunication... Broadcast Stations § 73.609 Zones. (a) For the purpose of allotment and assignment, the United States is divided into three zones as follows: (1) Zone I consists of that portion of the United States located...

  14. 47 CFR 73.609 - Zones.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Zones. 73.609 Section 73.609 Telecommunication... Broadcast Stations § 73.609 Zones. (a) For the purpose of allotment and assignment, the United States is divided into three zones as follows: (1) Zone I consists of that portion of the United States located...

  15. 47 CFR 73.609 - Zones.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 4 2013-10-01 2013-10-01 false Zones. 73.609 Section 73.609 Telecommunication... Broadcast Stations § 73.609 Zones. (a) For the purpose of allotment and assignment, the United States is divided into three zones as follows: (1) Zone I consists of that portion of the United States located...

  16. 47 CFR 73.609 - Zones.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 4 2012-10-01 2012-10-01 false Zones. 73.609 Section 73.609 Telecommunication... Broadcast Stations § 73.609 Zones. (a) For the purpose of allotment and assignment, the United States is divided into three zones as follows: (1) Zone I consists of that portion of the United States located...

  17. 47 CFR 73.609 - Zones.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 4 2011-10-01 2011-10-01 false Zones. 73.609 Section 73.609 Telecommunication... Broadcast Stations § 73.609 Zones. (a) For the purpose of allotment and assignment, the United States is divided into three zones as follows: (1) Zone I consists of that portion of the United States located...

  18. Mixing-dependent Reactions in the Hyporheic Zone: Laboratory and Numerical Experiments

    NASA Astrophysics Data System (ADS)

    Santizo, K. Y.; Eastes, L. A.; Hester, E. T.; Widdowson, M.

    2017-12-01

    The hyporheic zone is the surface water-groundwater interface surrounding the river's perimeter. Prior research demonstrates the ability of the hyporheic zone to attenuate pollutants when surface water cycles through reactive sediments (non-mixing-dependent reactions). However, the colocation of both surface and ground water within hyporheic sediments also allows mixing-dependent reactions that require mixing of reactants from these two water sources. Recent modeling studies show these mixing zones can be small under steady state homogeneous conditions, but do not validate those results in the laboratory or explore the range of hydrological characteristics that control the extent of mixing. Our objective was to simulate the mixing zone, quantify its thickness, and probe its hydrological controls using a "mix" of laboratory and numerical experiments. For the lab experiments, a hyporheic zone was simulated in a sand mesocosm, and a mixing-dependent abiotic reaction of sodium sulfite and dissolved oxygen was induced. Oxygen concentration response and oxygen consumption were visualized via planar optodes. Sulfate production by the mixing-dependent reaction was measured by fluid samples and a spectrophometer. Key hydrologic controls varied in the mesocosm included head gradient driving hyporheic exchange and hydraulic conductivity/heterogeneity. Results show a clear mixing area, sulfate production, and oxygen gradient. Mixing zone length (hyporheic flow cell size) and thickness both increase with the driving head gradient. For the numerical experiments, transient surface water boundary conditions were implemented together with heterogeneity of hydraulic conductivity. Results indicate that both fluctuating boundary conditions and heterogeneity increase mixing-dependent reaction. The hyporheic zone is deemed an attenuation hotspot by multiple studies, but here we demonstrate its potential for mixing-dependent reactions and the influence of important hydrological

  19. Control of oxygen tension recapitulates zone-specific functions in human liver microphysiology systems.

    PubMed

    Lee-Montiel, Felipe T; George, Subin M; Gough, Albert H; Sharma, Anup D; Wu, Juanfang; DeBiasio, Richard; Vernetti, Lawrence A; Taylor, D Lansing

    2017-10-01

    This article describes our next generation human Liver Acinus MicroPhysiology System (LAMPS). The key demonstration of this study was that Zone 1 and Zone 3 microenvironments can be established by controlling the oxygen tension in individual devices over the range of ca. 3 to 13%. The oxygen tension was computationally modeled using input on the microfluidic device dimensions, numbers of cells, oxygen consumption rates of hepatocytes, the diffusion coefficients of oxygen in different materials and the flow rate of media in the MicroPhysiology System (MPS). In addition, the oxygen tension was measured using a ratiometric imaging method with the oxygen sensitive dye, Tris(2,2'-bipyridyl) dichlororuthenium(II) hexahydrate (RTDP) and the oxygen insensitive dye, Alexa 488. The Zone 1 biased functions of oxidative phosphorylation, albumin and urea secretion and Zone 3 biased functions of glycolysis, α1AT secretion, Cyp2E1 expression and acetaminophen toxicity were demonstrated in the respective Zone 1 and Zone 3 MicroPhysiology System. Further improvements in the Liver Acinus MicroPhysiology System included improved performance of selected nonparenchymal cells, the inclusion of a porcine liver extracellular matrix to model the Space of Disse, as well as an improved media to support both hepatocytes and non-parenchymal cells. In its current form, the Liver Acinus MicroPhysiology System is most amenable to low to medium throughput, acute through chronic studies, including liver disease models, prioritizing compounds for preclinical studies, optimizing chemistry in structure activity relationship (SAR) projects, as well as in rising dose studies for initial dose ranging. Impact statement Oxygen zonation is a critical aspect of liver functions. A human microphysiology system is needed to investigate the impact of zonation on a wide range of liver functions that can be experimentally manipulated. Because oxygen zonation has such diverse physiological effects in the liver, we

  20. Association of T-Zone Reticular Networks and Conduits with Ectopic Lymphoid Tissues in Mice and Humans

    PubMed Central

    Link, Alexander; Hardie, Debbie L.; Favre, Stéphanie; Britschgi, Mirjam R.; Adams, David H.; Sixt, Michael; Cyster, Jason G.; Buckley, Christopher D.; Luther, Sanjiv A.

    2011-01-01

    Ectopic or tertiary lymphoid tissues (TLTs) are often induced at sites of chronic inflammation. They typically contain various hematopoietic cell types, high endothelial venules, and follicular dendritic cells; and are organized in lymph node–like structures. Although fibroblastic stromal cells may play a role in TLT induction and persistence, they have remained poorly defined. Herein, we report that TLTs arising during inflammation in mice and humans in a variety of tissues (eg, pancreas, kidney, liver, and salivary gland) contain stromal cell networks consisting of podoplanin+ T-zone fibroblastic reticular cells (TRCs), distinct from follicular dendritic cells. Similar to lymph nodes, TRCs were present throughout T-cell–rich areas and had dendritic cells associated with them. They expressed lymphotoxin (LT) β receptor (LTβR), produced CCL21, and formed a functional conduit system. In rat insulin promoter–CXCL13–transgenic pancreas, the maintenance of TRC networks and conduits was partially dependent on LTβR and on lymphoid tissue inducer cells expressing LTβR ligands. In conclusion, TRCs and conduits are hallmarks of secondary lymphoid organs and of well-developed TLTs, in both mice and humans, and are likely to act as important scaffold and organizer cells of the T-cell–rich zone. PMID:21435450

  1. Short-crested waves in the surf zone

    NASA Astrophysics Data System (ADS)

    Wei, Zhangping; Dalrymple, Robert A.; Xu, Munan; Garnier, Roland; Derakhti, Morteza

    2017-05-01

    This study investigates short-crested waves in the surf zone by using the mesh-free Smoothed Particle Hydrodynamics model, GPUSPH. The short-crested waves are created by generating intersecting wave trains in a numerical wave basin with a beach. We first validate the numerical model for short-crested waves by comparison with large-scale laboratory measurements. Then short-crested wave breaking over a planar beach is studied comprehensively. We observe rip currents as discussed in Dalrymple (1975) and undertow created by synchronous intersecting waves. The wave breaking of the short-crested wavefield created by the nonlinear superposition of intersecting waves and wave-current interaction result in the formation of isolated breakers at the ends of breaking wave crests. Wave amplitude diffraction at these isolated breakers gives rise to an increase in the alongshore wave number in the inner surf zone. Moreover, 3-D vortices and multiple circulation cells with a rotation frequency much lower than the incident wave frequency are observed across the outer surf zone to the beach. Finally, we investigate vertical vorticity generation under short-crested wave breaking and find that breaking of short-crested waves generates vorticity as pointed out by Peregrine (1998). Vorticity generation is not only observed under short-crested waves with a limited number of wave components but also under directional wave spectra.

  2. 33 CFR 3.65-15 - Sector Columbia River Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.65-15 Section 3.65-15 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES Thirteenth Coast Guard District § 3.65-15 Sector Columbia River Marine Inspection Zone and Captain of the Port Zone. Sector Columbia River's office is located in Astoria...

  3. 33 CFR 3.65-15 - Sector Columbia River Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.65-15 Section 3.65-15 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES Thirteenth Coast Guard District § 3.65-15 Sector Columbia River Marine Inspection Zone and Captain of the Port Zone. Sector Columbia River's office is located in Astoria...

  4. 33 CFR 3.65-15 - Sector Columbia River Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.65-15 Section 3.65-15 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES Thirteenth Coast Guard District § 3.65-15 Sector Columbia River Marine Inspection Zone and Captain of the Port Zone. Sector Columbia River's office is located in Astoria...

  5. 33 CFR 3.65-15 - Sector Columbia River Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.65-15 Section 3.65-15 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES Thirteenth Coast Guard District § 3.65-15 Sector Columbia River Marine Inspection Zone and Captain of the Port Zone. Sector Columbia River's office is located in Astoria...

  6. TLR4 signaling augments B lymphocyte migration and overcomes the restriction that limits access to germinal center dark zones

    PubMed Central

    Hwang, Il-Young; Park, Chung; Harrison, Kathleen

    2009-01-01

    B lymphocyte–intrinsic Toll-like receptor (TLR) signals amplify humoral immunity and can exacerbate autoimmune diseases. We identify a new mechanism by which TLR signals may contribute to autoimmunity and chronic inflammation. We show that TLR4 signaling enhances B lymphocyte trafficking into lymph nodes (LNs), induces B lymphocyte clustering and interactions within LN follicles, leads to sustained in vivo B cell proliferation, overcomes the restriction that limits the access of nonantigen-activated B cells to germinal center dark zones, and enhances the generation of memory and plasma cells. Intravital microscopy and in vivo tracking studies of B cells transferred to recipient mice revealed that TLR4-activated, but not nonstimulated, B cells accumulated within the dark zones of preexisting germinal centers even when transferred with antigen-specific B cells. The TLR4-activated cells persist much better than nonstimulated cells, expanding both within the memory and plasma cell compartments. TLR-mediated activation of B cells may help to feed and stabilize the spontaneous and ectopic germinal centers that are so commonly found in autoimmune individuals and that accompany chronic inflammation. PMID:19917774

  7. Monoclonal Antibody Therapy Before Stem Cell Transplant in Treating Patients With Relapsed or Refractory Lymphoid Malignancies

    ClinicalTrials.gov

    2017-10-10

    Adult Nasal Type Extranodal NK/T-cell Lymphoma; Anaplastic Large Cell Lymphoma; Angioimmunoblastic T-cell Lymphoma; Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Hepatosplenic T-cell Lymphoma; Intraocular Lymphoma; Nodal Marginal Zone B-cell Lymphoma; Noncutaneous Extranodal Lymphoma; Peripheral T-cell Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Adult T-cell Leukemia/Lymphoma; Recurrent Cutaneous T-cell Non-Hodgkin Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Mycosis Fungoides/Sezary Syndrome; Recurrent Small Lymphocytic Lymphoma; Refractory Hairy Cell Leukemia; Small Intestine Lymphoma; Splenic Marginal Zone Lymphoma; T-cell Large Granular Lymphocyte Leukemia; Testicular Lymphoma; Waldenström Macroglobulinemia

  8. Rift Zone Abandonment and Reconfiguration in Hawaii: Evidence from Mauna Loa’s Ninole Rift Zone

    NASA Astrophysics Data System (ADS)

    Morgan, J. K.; Park, J.; Zelt, C. A.

    2009-12-01

    Large oceanic volcanoes commonly develop elongate rift zones that disperse viscous magmas to the distal reaches of the edifice. Intrusion and dike propagation occur under tension perpendicular to the rift zone, controlled by topography, magmatic pressures, and deformation of the edifice. However, as volcanoes grow and interact, the controlling stress fields can change, potentially altering the orientations and activities of rift zones. This phenomenon is probably common, and can produce complex internal structures that influence the evolution of a volcano and its neighbors. However, little direct evidence for such rift zone reconfiguration exists, primarily due to poor preservation or recognition of earlier volcanic configurations. A new onshore-offshore 3-D seismic velocity model for the Island of Hawaii, derived from a joint tomographic inversion of an offshore airgun shot - onshore receiver geometry and earthquake sources beneath the island, demonstrates a complicated history of rift zone reconfiguration on Mauna Loa volcano, Hawaii, including wholesale rift zone abandonment. Mauna Loa’s southeast flank contains a massive high velocity intrusive complex, now buried beneath flows derived from Mauna Loa’s active southwest rift zone (SWRZ). Introduced here as the Ninole Rift Zone, this feature extends more than 60 km south of Mauna Loa’s summit, spans a depth range of ~2-14 km below sea level, and is the probable source of the 100-200 ka Ninole volcanics in several prominent erosional hills. A lack of high velocities beneath the upper SWRZ and its separate zone of high velocities on the submarine flank, indicate that the younger rift zone was built upon a pre-existing edifice that emanated from the Ninole rift zone. The ancient Ninole rift zone may stabilize Mauna Loa’s southeast flank, focusing recent volcanic activity and deformation onto the unbuttressed west flank. The upper portion of the Ninole rift zone appears to have migrated westward over time

  9. 33 CFR 3.55-15 - Sector San Diego Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.55-15 Section 3.55-15 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES Eleventh Coast Guard District § 3.55-15 Sector San Diego Marine Inspection Zone and Captain of the Port Zone. Sector San Diego's office is located in San Diego, CA. The...

  10. 33 CFR 3.25-20 - Sector North Carolina Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.25-20 Section 3.25-20 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES Fifth Coast Guard District § 3.25-20 Sector North Carolina Marine Inspection Zone and Captain of the Port Zone. Sector North Carolina's office is located in Wilmington, NC...

  11. 33 CFR 3.55-15 - Sector San Diego Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.55-15 Section 3.55-15 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES Eleventh Coast Guard District § 3.55-15 Sector San Diego Marine Inspection Zone and Captain of the Port Zone. Sector San Diego's office is located in San Diego, CA. The...

  12. 33 CFR 3.55-15 - Sector San Diego Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.55-15 Section 3.55-15 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES Eleventh Coast Guard District § 3.55-15 Sector San Diego Marine Inspection Zone and Captain of the Port Zone. Sector San Diego's office is located in San Diego, CA. The...

  13. 33 CFR 3.55-15 - Sector San Diego Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.55-15 Section 3.55-15 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES Eleventh Coast Guard District § 3.55-15 Sector San Diego Marine Inspection Zone and Captain of the Port Zone. Sector San Diego's office is located in San Diego, CA. The...

  14. 33 CFR 3.25-20 - Sector North Carolina Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.25-20 Section 3.25-20 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES Fifth Coast Guard District § 3.25-20 Sector North Carolina Marine Inspection Zone and Captain of the Port Zone. Sector North Carolina's office is located in Wilmington, NC...

  15. 33 CFR 3.25-20 - Sector North Carolina Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.25-20 Section 3.25-20 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES Fifth Coast Guard District § 3.25-20 Sector North Carolina Marine Inspection Zone and Captain of the Port Zone. Sector North Carolina's office is located in Wilmington, NC...

  16. 33 CFR 3.55-15 - Sector San Diego Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.55-15 Section 3.55-15 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES Eleventh Coast Guard District § 3.55-15 Sector San Diego Marine Inspection Zone and Captain of the Port Zone. Sector San Diego's office is located in San Diego, CA. The...

  17. 33 CFR 3.25-20 - Sector North Carolina Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.25-20 Section 3.25-20 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES Fifth Coast Guard District § 3.25-20 Sector North Carolina Marine Inspection Zone and Captain of the Port Zone. Sector North Carolina's office is located in Wilmington, NC...

  18. 33 CFR 165.503 - Security Zone; Captain of the Port Hampton Roads Zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Port Hampton Roads Zone. 165.503 Section 165.503 Navigation and Navigable Waters COAST GUARD... § 165.503 Security Zone; Captain of the Port Hampton Roads Zone. (a) Definitions. As used in this... been authorized by the Captain of the Port (COTP), Hampton Roads, Virginia to act on his or her behalf...

  19. Quantitative trait locus mapping of genes associated with vacuolation in the adrenal X-zone of the DDD/Sgn inbred mouse.

    PubMed

    Suto, Jun-Ichi

    2012-11-06

    Adrenal gland of mice contains a transient zone between the adrenal cortex and the adrenal medulla: the X-zone. There are clear strain differences in terms of X-zone morphology. Nulliparous females of the inbred mouse DDD strain develop adrenal X-zones containing exclusively vacuolated cells, whereas females of the inbred mouse B6 strain develop X-zones containing only non-vacuolated cells. The X-zone vacuolation is a physiologic process associated with the X-zone degeneration and is tightly regulated by genetic factors. Identification of the genetic factors controlling such strain differences should help analyze the X-zone function. In this study, a quantitative trait locus (QTL) analysis for the extent of X-zone vacuolation was performed for two types of F2 female mice: F2Ay mice (F2 mice with the Ay allele) and F2 non-Ay mice (F2 mice without the Ay allele). These were produced by crossing B6 females and DDD.Cg-Ay males. DDD.Cg-Ay is a congenic mouse strain for the Ay allele at the agouti locus and is used for this study because a close association between the X-zone morphology and the agouti locus genotype has been suggested. The Ay allele is dominant and homozygous lethal; therefore, living Ay mice are invariably heterozygotes. Single QTL scans identified significant QTLs on chromosomes 1, 2, 6, and X for F2 non-Ay mice, and on chromosomes 2, 6, and 12 for F2Ay mice. The QTL on chromosome 2 was considered to be because of the agouti locus, which has been suggested to be associated with X-zone vacuolation. A significant QTL that interacted with the agouti locus was identified on chromosome 8. The extent of X-zone vacuolation in DDD females was controlled by multiple genes with complex interactions. The murine X-zone is considered analogous structure to the human fetal zone. Therefore, the results of this study will aid in understanding function of not only of the X-zone but also of the human fetal zone. Identifying the genes responsible for the QTLs will be

  20. Quantitative trait locus mapping of genes associated with vacuolation in the adrenal X-zone of the DDD/Sgn inbred mouse

    PubMed Central

    2012-01-01

    Background Adrenal gland of mice contains a transient zone between the adrenal cortex and the adrenal medulla: the X-zone. There are clear strain differences in terms of X-zone morphology. Nulliparous females of the inbred mouse DDD strain develop adrenal X-zones containing exclusively vacuolated cells, whereas females of the inbred mouse B6 strain develop X-zones containing only non-vacuolated cells. The X-zone vacuolation is a physiologic process associated with the X-zone degeneration and is tightly regulated by genetic factors. Identification of the genetic factors controlling such strain differences should help analyze the X-zone function. In this study, a quantitative trait locus (QTL) analysis for the extent of X-zone vacuolation was performed for two types of F2 female mice: F2Ay mice (F2 mice with the Ay allele) and F2 non-Ay mice (F2 mice without the Ay allele). These were produced by crossing B6 females and DDD.Cg-Ay males. DDD.Cg-Ay is a congenic mouse strain for the Ay allele at the agouti locus and is used for this study because a close association between the X-zone morphology and the agouti locus genotype has been suggested. The Ay allele is dominant and homozygous lethal; therefore, living Ay mice are invariably heterozygotes. Results Single QTL scans identified significant QTLs on chromosomes 1, 2, 6, and X for F2 non-Ay mice, and on chromosomes 2, 6, and 12 for F2Ay mice. The QTL on chromosome 2 was considered to be because of the agouti locus, which has been suggested to be associated with X-zone vacuolation. A significant QTL that interacted with the agouti locus was identified on chromosome 8. Conclusions The extent of X-zone vacuolation in DDD females was controlled by multiple genes with complex interactions. The murine X-zone is considered analogous structure to the human fetal zone. Therefore, the results of this study will aid in understanding function of not only of the X-zone but also of the human fetal zone. Identifying the genes

  1. Formulating a coastal zone health metric for landuse impact management in urban coastal zones.

    PubMed

    Anilkumar, P P; Varghese, Koshy; Ganesh, L S

    2010-11-01

    The need for ICZM arises often due to inadequate or inappropriate landuse planning practices and policies, especially in urban coastal zones which are more complex due to the larger number of components, their critical dimensions, attributes and interactions. A survey of literature shows that there is no holistic metric for assessing the impacts of landuse planning on the health of a coastal zone. Thus there is a need to define such a metric. The proposed metric, CHI (Coastal zone Health Indicator), developed on the basis of coastal system sustainability, attempts to gauge the health status of any coastal zone. It is formulated and modeled through an expert survey and pertains to the characteristic components of coastal zones, their critical dimensions, and relevant attributes. The proposed metric is applied to two urban coastal zones and validated. It can be used for more coast friendly and sustainable landuse planning/masterplan preparation and thereby for the better management of landuse impacts on coastal zones. Copyright 2010 Elsevier Ltd. All rights reserved.

  2. Integument cell differentiation in dandelions (Taraxacum, Asteraceae, Lactuceae) with special attention paid to plasmodesmata.

    PubMed

    Płachno, Bartosz J; Kurczyńska, Ewa; Świątek, Piotr

    2016-09-01

    The aim of the paper is to determine what happens with plasmodesmata when mucilage is secreted into the periplasmic space in plant cells. Ultrastructural analysis of the periendothelial zone mucilage cells was performed on examples of the ovule tissues of several sexual and apomictic Taraxacum species. The cytoplasm of the periendothelial zone cells was dense, filled by numerous organelles and profiles of rough endoplasmic reticulum and active Golgi dictyosomes with vesicles that contained fibrillar material. At the beginning of the differentiation process of the periendothelial zone, the cells were connected by primary plasmodesmata. However, during the differentiation and the thickening of the cell walls (mucilage deposition), the plasmodesmata become elongated and associated with cytoplasmic bridges. The cytoplasmic bridges may connect the protoplast to the plasmodesmata through the mucilage layers in order to maintain cell-to-cell communication during the differentiation of the periendothelial zone cells.

  3. 78 FR 41694 - Safety Zone; Fireworks Events in Captain of the Port New York Zone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-11

    ... Zone; Fireworks Events in Captain of the Port New York Zone AGENCY: Coast Guard, DHS. ACTION: Notice of enforcement of regulation. SUMMARY: The Coast Guard will enforce safety zones in the Captain of the Port New York Zone on the specified dates and times. This action is necessary to ensure the safety of vessels...

  4. Recognizing nodal marginal zone lymphoma: recent advances and pitfalls. A systematic review

    PubMed Central

    van den Brand, Michiel; van Krieken, J. Han J.M.

    2013-01-01

    The diagnosis of nodal marginal zone lymphoma is one of the remaining problem areas in hematopathology. Because no established positive markers exist for this lymphoma, it is frequently a diagnosis of exclusion, making distinction from other low-grade B-cell lymphomas difficult or even impossible. This systematic review summarizes and discusses the current knowledge on nodal marginal zone lymphoma, including clinical features, epidemiology and etiology, histology, and cytogenetic and molecular features. In particular, recent advances in diagnostics and pathogenesis are discussed. New immunohistochemical markers have become available that could be used as positive markers for nodal marginal zone lymphoma. These markers could be used to ensure more homogeneous study groups in future research. Also, recent gene expression studies and studies describing specific gene mutations have provided clues to the pathogenesis of nodal marginal zone lymphoma, suggesting deregulation of the nuclear factor kappa B pathway. Nevertheless, nodal marginal zone lymphoma remains an enigmatic entity, requiring further study to define its pathogenesis to allow an accurate diagnosis and tailored treatment. However, recent data indicate that it is not related to splenic or extranodal lymphoma, and that it is also not related to lymphoplasmacytic lymphoma. Thus, even though the diagnosis is not always easy, it is clearly a separate entity. PMID:23813646

  5. Neural stem cells in the immature, but not the mature, subventricular zone respond robustly to traumatic brain injury.

    PubMed

    Goodus, Matthew T; Guzman, Alanna M; Calderon, Frances; Jiang, Yuhui; Levison, Steven W

    2015-01-01

    Pediatric traumatic brain injury is a significant problem that affects many children each year. Progress is being made in developing neuroprotective strategies to combat these injuries. However, investigators are a long way from therapies to fully preserve injured neurons and glia. To restore neurological function, regenerative strategies will be required. Given the importance of stem cells in repairing damaged tissues and the known persistence of neural precursors in the subventricular zone (SVZ), we evaluated regenerative responses of the SVZ to a focal brain lesion. As tissues repair more slowly with aging, injury responses of male Sprague Dawley rats at 6, 11, 17, and 60 days of age and C57Bl/6 mice at 14 days of age were compared. In the injured immature animals, cell proliferation in the dorsolateral SVZ more than doubled by 48 h. By contrast, the proliferative response was almost undetectable in the adult brain. Three approaches were used to assess the relative numbers of bona fide neural stem cells, as follows: the neurosphere assay (on rats injured at postnatal day 11, P11), flow cytometry using a novel 4-marker panel (on mice injured at P14) and staining for stem/progenitor cell markers in the niche (on rats injured at P17). Precursors from the injured immature SVZ formed almost twice as many spheres as precursors from uninjured age-matched brains. Furthermore, spheres formed from the injured brain were larger, indicating that the neural precursors that formed these spheres divided more rapidly. Flow cytometry revealed a 2-fold increase in the percentage of stem cells, a 4-fold increase in multipotential progenitor-3 cells and a 2.5-fold increase in glial-restricted progenitor-2/multipotential-3 cells. Analogously, there was a 2-fold increase in the mitotic index of nestin+/Mash1- immunoreactive cells within the immediately subependymal region. As the early postnatal SVZ is predominantly generating glial cells, an expansion of precursors might not

  6. 78 FR 57482 - Safety Zone; Fireworks Event in Captain of the Port New York Zone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-19

    ... York Zone on the specified date and time. This action is necessary to ensure the safety of vessels and... regulation for the safety zone described in 33 CFR 165.160 will be enforced on the date and time listed in... Zone; Fireworks Event in Captain of the Port New York Zone AGENCY: Coast Guard, DHS. ACTION: Notice of...

  7. 77 FR 59551 - Safety Zone; Fireworks Event in Captain of the Port New York Zone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-28

    ... Zone; Fireworks Event in Captain of the Port New York Zone AGENCY: Coast Guard, DHS. ACTION: Notice of enforcement of regulation. SUMMARY: The Coast Guard will enforce a safety zone in the Captain of the Port New York Zone on the specified date and time. This action is necessary to ensure the safety of vessels and...

  8. Ibrutinib in Treating Relapsed or Refractory B-Cell Non-Hodgkin Lymphoma in Patients With HIV Infection

    ClinicalTrials.gov

    2015-08-18

    Adult B Acute Lymphoblastic Leukemia; Chronic Lymphocytic Leukemia; Cutaneous B-Cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone Lymphoma of Mucosa-Associated Lymphoid Tissue; HIV Infection; Intraocular Lymphoma; Multicentric Angiofollicular Lymphoid Hyperplasia; Nodal Marginal Zone Lymphoma; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Immunoblastic Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Small Lymphocytic Lymphoma; Refractory Chronic Lymphocytic Leukemia; Refractory Hairy Cell Leukemia; Refractory Plasma Cell Myeloma; Small Intestinal Lymphoma; Splenic Marginal Zone Lymphoma; Testicular Lymphoma; Waldenstrom Macroglobulinemia

  9. Inhibition of osteoclast bone resorption activity through osteoprotegerin-induced damage of the sealing zone.

    PubMed

    Song, Ruilong; Gu, Jianhong; Liu, Xuezhong; Zhu, Jiaqiao; Wang, Qichao; Gao, Qian; Zhang, Jiaming; Cheng, Laiyang; Tong, Xishuai; Qi, Xinyi; Yuan, Yan; Liu, Zongping

    2014-09-01

    Bone remodeling is dependent on the dynamic equilibrium between osteoclast-mediated bone resorption and osteoblast-mediated osteogenesis. The sealing zone is an osteoclast-specific cytoskeletal structure, the integrity of which is critical for osteoclast-mediated bone resorption. To date, studies have focused mainly on the osteoprotegerin (OPG)‑induced inhibition of osteoclast differentiation through the OPG/receptor activator of the nuclear factor kappa-B ligand (RANKL)/RANK system, which affects the bone resorption of osteoclasts. However, the effects of OPG on the sealing zone have not been reported to date. In this study, the formation of the sealing zone was observed by Hoffman modulation contrast (HMC) microscopy and confocal laser scanning microscopy. The effects of OPG on the existing sealing zone and osteoclast-mediated bone resorption activity, as well as the regulatory role of genes involved in the formation of the sealing zone were examined by immunofluorescence staining, HMC microscopy, quantitative reverse transcription polymerase chain reaction (RT-qPCR), western blot analysis and scanning electron microscopy. The sealing zone was formed on day 5, with belt-like protuberances at the cell edge and scattered distribution of cell nuclei, but no filopodia. The sealing zone was intact in the untreated control group. However, defects in the sealing zone were observed in the OPG-treated group (20 ng/ml) and the structure was absent in the groups treated with 40 and 80 ng/ml OPG. The podosomes showed a scattered or clustered distribution between the basal surface of the osteoclasts and the well surface. Furthermore, resorption lacunae were not detected in the 20 ng/ml OPG-treated group, indicating the loss of osteoclast-mediated bone resorption activity. Treatment with OPG resulted in a significant decrease in the expression of Arhgef8/Net1 and DOCK5 Rho guanine nucleotide exchange factors (RhoGEFs), 10 of 18 RhoGTPases (RhoA, RhoB, cdc42v1, cdc42v2

  10. [Current approach to zoning atomic shipbuilding plants].

    PubMed

    Blekher, A Ia

    2005-01-01

    The paper discusses the currently introduced radiation-and-hygienic system for zoning atomic shipbuilding plants, in accordance with which three radiation-and-hygienic zones (a strict regime zone, a controlled approach zone, and a free regime zone) are established at the plant site and two zones (a sanitary-and-protective zone and a follow-up zone) are also established outside the plant site.

  11. 49 CFR 71.13 - Samoa zone.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Samoa zone. 71.13 Section 71.13 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.13 Samoa zone. The eighth zone, the Samoa standard time zone, includes that part of the United States that is between 169 degrees...

  12. 49 CFR 71.14 - Chamorro Zone.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Chamorro Zone. 71.14 Section 71.14 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.14 Chamorro Zone. The ninth zone, the Chamorro standard time zone, includes the Island of Guam and the Commonwealth of the Northern...

  13. 49 CFR 71.10 - Pacific zone.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.10 Pacific zone. The fifth zone, the Pacific standard time zone, includes that part of the continental United States that is west of the boundary line between the mountain and Pacific standard time zones described in § 71.9, but...

  14. Analysis of traffic congestion induced by the work zone

    NASA Astrophysics Data System (ADS)

    Fei, L.; Zhu, H. B.; Han, X. L.

    2016-05-01

    Based on the cellular automata model, a meticulous two-lane cellular automata model is proposed, in which the driving behavior difference and the difference of vehicles' accelerations between the moving state and the starting state are taken into account. Furthermore the vehicles' motion is refined by using the small cell of one meter long. Then accompanied by coming up with a traffic management measure, a two-lane highway traffic model containing a work zone is presented, in which the road is divided into normal area, merging area and work zone. The vehicles in different areas move forward according to different lane changing rules and position updating rules. After simulation it is found that when the density is small the cluster length in front of the work zone increases with the decrease of the merging probability. Then the suitable merging length and the appropriate speed limit value are recommended. The simulation result in the form of the speed-flow diagram is in good agreement with the empirical data. It indicates that the presented model is efficient and can partially reflect the real traffic. The results may be meaningful for traffic optimization and road construction management.

  15. Effects of growth factors and glucosamine on porcine mandibular condylar cartilage cells and hyaline cartilage cells for tissue engineering applications.

    PubMed

    Wang, Limin; Detamore, Michael S

    2009-01-01

    Temporomandibular joint (TMJ) condylar cartilage is a distinct cartilage that has both fibrocartilaginous and hyaline-like character, with a thin proliferative zone that separates the fibrocartilaginous fibrous zone at the surface from the hyaline-like mature and hypertrophic zones below. In this study, we compared the effects of insulin-like growth factor-I (IGF-I), basic fibroblast growth factor (bFGF), transforming growth factor beta1 (TGF-beta1), and glucosamine sulphate on porcine TMJ condylar cartilage and ankle cartilage cells in monolayer culture. In general, TMJ condylar cartilage cells proliferated faster than ankle cartilage cells, while ankle cells produced significantly greater amounts of glycosaminoglycans (GAGs) and collagen than TMJ condylar cartilage cells. IGF-I and bFGF were potent stimulators of TMJ cell proliferation, while no signals statistically outperformed controls for ankle cell proliferation. IGF-I was the most effective signal for GAG production with ankle cells, and the most potent upregulator of collagen synthesis for both cell types. Glucosamine sulphate promoted cell proliferation and biosynthesis at specific concentrations and outperformed growth factors in certain instances. In conclusion, hyaline cartilage cells had lower cell numbers and superior biosynthesis compared to TMJ condylar cartilage cells, and we have found IGF-I at 100 ng/mL and glucosamine sulphate at 100 microg/mL to be the most effective signals for these cells under the prescribed conditions.

  16. The generalized mean zone plate

    NASA Astrophysics Data System (ADS)

    Xia, Tian; Cheng, Shubo; Tao, Shaohua

    2018-06-01

    In this paper a generalized mean zone plate is proposed, which generates twin foci located at the positions satisfying the expression of the generalized mean, which includes the m-golden mean, precious mean, and so on. The generalized mean zone plate can be designed to generate twin foci with various position ratios. The diffraction properties of the generalized mean zone plates have been investigated with simulations and experiments. The results show that the ratio of the positions of the twin foci for the generalized mean zone plate can be designed with the selected zone plate parameters.

  17. 49 CFR 71.11 - Alaska zone.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Alaska zone. 71.11 Section 71.11 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.11 Alaska zone. The sixth zone, the Alaska standard time zone, includes the entire State of Alaska, except as provided in § 71.12...

  18. 49 CFR 71.6 - Central zone.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.6 Central zone. The third zone, the central standard time zone, includes that part of the United States that is west of the boundary line between the eastern and central standard time zones described in § 71.5 and east of the...

  19. 49 CFR 71.8 - Mountain zone.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.8 Mountain zone. The fourth zone, the mountain standard time zone, includes that part of the United States that is west of the boundary line between the central and mountain standard time zones described in § 71.7 and east of the...

  20. High-quality Silicon Films Prepared by Zone-melting Recrystallization

    NASA Technical Reports Server (NTRS)

    Chen, C. K.; Geis, M. W.; Tsaur, B. Y.; Fan, J. C. C.

    1984-01-01

    The graphite strip heater zone melting recrystallization (ZMR) technique is described. The material properties of the ZMR films, and SOI device results are reviewed. Although our ZMR work is primarily motivated by integrated circuit applications, this work evolved in part from earlier research on laser crystallization of thick amorphous GaAs and Si films, which was undertaken with the goal of producing low cost photovoltaic materials. The ZMR growth process and its effect on the properties of the recrystallized films may contribute some insight to a general understanding of the rapid recrystallization of Si for solar cells. Adaptation of ZMR for solar cell fabrication is considered.

  1. Csf2 null mutation alters placental gene expression and trophoblast glycogen cell and giant cell abundance in mice.

    PubMed

    Sferruzzi-Perri, Amanda N; Macpherson, Anne M; Roberts, Claire T; Robertson, Sarah A

    2009-07-01

    Genetic deficiency in granulocyte-macrophage colony-stimulating factor (CSF2, GM-CSF) results in altered placental structure in mice. To investigate the mechanism of action of CSF2 in placental morphogenesis, the placental gene expression and cell composition were examined in Csf2 null mutant and wild-type mice. Microarray and quantitative RT-PCR analyses on Embryonic Day (E) 13 placentae revealed that the Csf2 null mutation caused altered expression of 17 genes not previously known to be associated with placental development, including Mid1, Cd24a, Tnfrsf11b, and Wdfy1. Genes controlling trophoblast differentiation (Ascl2, Tcfeb, Itgav, and Socs3) were also differentially expressed. The CSF2 ligand and the CSF2 receptor alpha subunit were predominantly synthesized in the placental junctional zone. Altered placental structure in Csf2 null mice at E15 was characterized by an expanded junctional zone and by increased Cx31(+) glycogen cells and cyclin-dependent kinase inhibitor 1C (CDKN1C(+), P57(Kip2+)) giant cells, accompanied by elevated junctional zone transcription of genes controlling spongiotrophoblast and giant cell differentiation and secretory function (Ascl2, Hand1, Prl3d1, and Prl2c2). Granzyme genes implicated in tissue remodeling and potentially in trophoblast invasion (Gzmc, Gzme, and Gzmf) were downregulated in the junctional zone of Csf2 null mutant placentae. These data demonstrate aberrant placental gene expression in Csf2 null mutant mice that is associated with altered differentiation and/or functional maturation of junctional zone trophoblast lineages, glycogen cells, and giant cells. We conclude that CSF2 is a regulator of trophoblast differentiation and placental development, which potentially influences the functional capacity of the placenta to support optimal fetal growth in pregnancy.

  2. 49 CFR 71.4 - Eastern zone.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Eastern zone. 71.4 Section 71.4 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.4 Eastern zone. The second zone, the eastern standard time zone, includes that part of the United States that is west of 67°30″ W...

  3. 49 CFR 71.3 - Atlantic zone.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Atlantic zone. 71.3 Section 71.3 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.3 Atlantic zone. The first zone, the Atlantic standard time zone, includes that part of the United States that is between 52°30″ W...

  4. CPI-613, Bendamustine Hydrochloride, and Rituximab in Treating Patients With Relapsed or Refractory B-Cell Non-Hodgkin Lymphoma

    ClinicalTrials.gov

    2017-05-25

    B-cell Adult Acute Lymphoblastic Leukemia; B-cell Chronic Lymphocytic Leukemia; Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Intraocular Lymphoma; Nodal Marginal Zone B-cell Lymphoma; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Mycosis Fungoides/Sezary Syndrome; Recurrent Small Lymphocytic Lymphoma; Refractory Chronic Lymphocytic Leukemia; Refractory Hairy Cell Leukemia; Small Intestine Lymphoma; Splenic Marginal Zone Lymphoma; Testicular Lymphoma; Waldenström Macroglobulinemia

  5. Progressive Inhibition by Water Deficit of Cell Wall Extensibility and Growth along the Elongation Zone of Maize Roots Is Related to Increased Lignin Metabolism and Progressive Stelar Accumulation of Wall Phenolics1

    PubMed Central

    Fan, Ling; Linker, Raphael; Gepstein, Shimon; Tanimoto, Eiichi; Yamamoto, Ryoichi; Neumann, Peter M.

    2006-01-01

    Water deficit caused by addition of polyethylene glycol 6000 at −0.5 MPa water potential to well-aerated nutrient solution for 48 h inhibited the elongation of maize (Zea mays) seedling primary roots. Segmental growth rates in the root elongation zone were maintained 0 to 3 mm behind the tip, but in comparison with well-watered control roots, progressive growth inhibition was initiated by water deficit as expanding cells crossed the region 3 to 9 mm behind the tip. The mechanical extensibility of the cell walls was also progressively inhibited. We investigated the possible involvement in root growth inhibition by water deficit of alterations in metabolism and accumulation of wall-linked phenolic substances. Water deficit increased expression in the root elongation zone of transcripts of two genes involved in lignin biosynthesis, cinnamoyl-CoA reductase 1 and 2, after only 1 h, i.e. before decreases in wall extensibility. Further increases in transcript expression and increased lignin staining were detected after 48 h. Progressive stress-induced increases in wall-linked phenolics at 3 to 6 and 6 to 9 mm behind the root tip were detected by comparing Fourier transform infrared spectra and UV-fluorescence images of isolated cell walls from water deficit and control roots. Increased UV fluorescence and lignin staining colocated to vascular tissues in the stele. Longitudinal bisection of the elongation zone resulted in inward curvature, suggesting that inner, stelar tissues were also rate limiting for root growth. We suggest that spatially localized changes in wall-phenolic metabolism are involved in the progressive inhibition of wall extensibility and root growth and may facilitate root acclimation to drying environments. PMID:16384904

  6. 33 CFR 3.35-40 - Sector Key West Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Zone and Captain of the Port Zone. 3.35-40 Section 3.35-40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL COAST GUARD AREAS, DISTRICTS, SECTORS, MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Seventh Coast Guard District § 3.35-40 Sector Key West Marine Inspection Zone...

  7. 33 CFR 3.35-40 - Sector Key West Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Zone and Captain of the Port Zone. 3.35-40 Section 3.35-40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL COAST GUARD AREAS, DISTRICTS, SECTORS, MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Seventh Coast Guard District § 3.35-40 Sector Key West Marine Inspection Zone...

  8. 33 CFR 3.35-40 - Sector Key West Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Zone and Captain of the Port Zone. 3.35-40 Section 3.35-40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL COAST GUARD AREAS, DISTRICTS, SECTORS, MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Seventh Coast Guard District § 3.35-40 Sector Key West Marine Inspection Zone...

  9. 33 CFR 3.35-40 - Sector Key West Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Zone and Captain of the Port Zone. 3.35-40 Section 3.35-40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL COAST GUARD AREAS, DISTRICTS, SECTORS, MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Seventh Coast Guard District § 3.35-40 Sector Key West Marine Inspection Zone...

  10. 33 CFR 3.35-40 - Sector Key West Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Zone and Captain of the Port Zone. 3.35-40 Section 3.35-40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY GENERAL COAST GUARD AREAS, DISTRICTS, SECTORS, MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Seventh Coast Guard District § 3.35-40 Sector Key West Marine Inspection Zone...

  11. 76 FR 17782 - Security Zone: Passenger Vessels, Sector Southeastern New England Captain of the Port Zone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-31

    ...-AA87 Security Zone: Passenger Vessels, Sector Southeastern New England Captain of the Port Zone AGENCY... extending the effective period for temporary fixed and moving security zones around certain passenger vessels in the Sector Southeastern New England Captain of the Port Zone through October 1, 2011. Temporary...

  12. 77 FR 19970 - Security Zones; 2012 Republican National Convention, Captain of the Port St. Petersburg Zone...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-03

    ...-AA87 Security Zones; 2012 Republican National Convention, Captain of the Port St. Petersburg Zone... Marine Science Technician First Class Nolan L. Ammons, Sector St. Petersburg Prevention Department, Coast... proposed rule would establish seven temporary security zones in the Captain of the Port St. Petersburg Zone...

  13. Adapter molecule Grb2-associated binder 1 is specifically expressed in marginal zone B cells and negatively regulates thymus-independent antigen-2 responses.

    PubMed

    Itoh, Shousaku; Itoh, Motoyuki; Nishida, Keigo; Yamasaki, Satoru; Yoshida, Yuichi; Narimatsu, Masahiro; Park, Sung Joo; Hibi, Masahiko; Ishihara, Katsuhiko; Hirano, Toshio

    2002-05-15

    Grb2-associated binder 1 (Gab1) is a member of the Gab/daughter of sevenless family of adapter molecules involved in the signal transduction pathways of a variety of growth factors, cytokines, and Ag receptors. To know the role for Gab1 in hematopoiesis and immune responses in vivo, we analyzed radiation chimeras reconstituted with fetal liver (FL) cells of Gab1(-/-) mice, because Gab1(-/-) mice are lethal to embryos. Transfer of Gab1(-/-) FL cells of 14.5 days post-coitum rescued lethally irradiated mice, indicating that Gab1 is not essential for hematopoiesis. Although mature T and B cell subsets developed normally in the peripheral lymphoid organs, reduction of pre-B cells and increase of myeloid cells in the Gab1(-/-) FL chimeras suggested the regulatory roles for Gab1 in hematopoiesis. The chimera showed augmented IgM and IgG1 production to thymus-independent (TI)-2 Ag, although they showed normal responses for thymus-dependent and TI-1 Ags, indicating its negative role specific to TI-2 response. Gab1(-/-) splenic B cells stimulated with anti-delta-dextran plus IL-4 plus IL-5 showed augmented IgM and IgG1 production in vitro that was corrected by the retrovirus-mediated transfection of the wild-type Gab1 gene, clearly demonstrating the cell-autonomous, negative role of Gab1. Furthermore, we showed that the negative role of Gab1 required its Src homology 2-containing tyrosine phosphatase-2 binding sites. Cell fractionation analysis revealed that nonfollicular B cells were responsible for the augmented Ab production in vitro. Consistent with these results, the Gab1 gene was expressed in marginal zone B cells but not follicular B cells. These results indicated that Gab1 is a unique negative regulator specific for TI-2 responses.

  14. Coastal zone management

    NASA Technical Reports Server (NTRS)

    Tilton, E. L., III

    1975-01-01

    A panel of federal and state representatives concerned with coastal zone affairs discussed their problems in this area. In addition, several demonstrations of the application of remote sensing technology to coastal zone management were described. These demonstrations were performed by several agencies in a variety of geographical areas.

  15. The soluble pattern recognition receptor PTX3 links humoral innate and adaptive immune responses by helping marginal zone B cells

    PubMed Central

    Sintes, Jordi; Polentarutti, Nadia; Walland, A. Cooper; Yeiser, John R.; Cunha, Cristina; Lacerda, João F.; Salvatori, Giovanni; Blander, J. Magarian

    2016-01-01

    Pentraxin 3 (PTX3) is a fluid-phase pattern recognition receptor of the humoral innate immune system with ancestral antibody-like properties but unknown antibody-inducing function. In this study, we found binding of PTX3 to splenic marginal zone (MZ) B cells, an innate-like subset of antibody-producing lymphocytes strategically positioned at the interface between the circulation and the adaptive immune system. PTX3 was released by a subset of neutrophils that surrounded the splenic MZ and expressed an immune activation–related gene signature distinct from that of circulating neutrophils. Binding of PTX3 promoted homeostatic production of IgM and class-switched IgG antibodies to microbial capsular polysaccharides, which decreased in PTX3-deficient mice and humans. In addition, PTX3 increased IgM and IgG production after infection with blood-borne encapsulated bacteria or immunization with bacterial carbohydrates. This immunogenic effect stemmed from the activation of MZ B cells through a neutrophil-regulated pathway that elicited class switching and plasmablast expansion via a combination of T cell–independent and T cell–dependent signals. Thus, PTX3 may bridge the humoral arms of the innate and adaptive immune systems by serving as an endogenous adjuvant for MZ B cells. This property could be harnessed to develop more effective vaccines against encapsulated pathogens. PMID:27621420

  16. Mutant IDH1 Disrupts the Mouse Subventricular Zone and Alters Brain Tumor Progression

    PubMed Central

    Pirozzi, Christopher J.; Carpenter, Austin B.; Waitkus, Matthew S.; Wang, Catherine Y.; Zhu, Huishan; Hansen, Landon J.; Chen, Lee H.; Greer, Paula K.; Feng, Jie; Wang, Yu; Bock, Cheryl B.; Fan, Ping; Spasojevic, Ivan; McLendon, Roger E.; Bigner, Darell D.; He, Yiping; Yan, Hai

    2017-01-01

    IDH1 mutations occur in the majority of low-grade gliomas and lead to the production of the oncometabolite, D-2-hydroxyglutarate (D-2HG). To understand the effects of tumor-associated mutant IDH1 (IDH1-R132H) on both the neural stem cell (NSC) population and brain tumorigenesis, genetically faithful cell lines and mouse model systems were generated. Here, it is reported that mouse NSCs expressing Idh1-R132H displayed reduced proliferation due to p53-mediated cell cycle arrest as well as a decreased ability to undergo neuronal differentiation. In vivo, Idh1-R132H expression reduced proliferation of cells within the germinal zone of the subventricular zone (SVZ). The NSCs within this area were dispersed and disorganized in mutant animals, suggesting that Idh1-R132H perturbed the NSCs and the microenvironment from which gliomas arise. Additionally, tumor-bearing animals expressing mutant Idh1 displayed a prolonged survival and also overexpressed Olig2, features consistent with IDH1-mutated human gliomas. These data indicate that mutant Idh1 disrupts the NSC microenvironment and the candidate cell of origin for glioma; thus, altering the progression of tumorigenesis. Additionally, this study provides a mutant Idh1 brain tumor model that genetically recapitulates human disease, laying the foundation for future investigations on mutant IDH1-mediated brain tumorigenesis and targeted therapy. PMID:28148827

  17. Etoposide, Filgrastim, and Plerixafor in Improving Stem Cell Mobilization in Treating Patients With Non-Hodgkin Lymphoma

    ClinicalTrials.gov

    2016-12-06

    Adult Acute Lymphoblastic Leukemia in Remission; Adult Grade III Lymphomatoid Granulomatosis; Adult Nasal Type Extranodal NK/T-cell Lymphoma; Anaplastic Large Cell Lymphoma; Angioimmunoblastic T-cell Lymphoma; Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Hepatosplenic T-cell Lymphoma; Nodal Marginal Zone B-cell Lymphoma; Noncutaneous Extranodal Lymphoma; Peripheral T-cell Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Adult T-cell Leukemia/Lymphoma; Recurrent Cutaneous T-cell Non-Hodgkin Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Mycosis Fungoides/Sezary Syndrome; Recurrent Small Lymphocytic Lymphoma; Refractory Chronic Lymphocytic Leukemia; Refractory Hairy Cell Leukemia; Small Intestine Lymphoma; Splenic Marginal Zone Lymphoma; T-cell Large Granular Lymphocyte Leukemia; Testicular Lymphoma; Waldenström Macroglobulinemia

  18. 33 CFR 3.05-20 - Sector Southeastern New England Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Marine Inspection Zone and Captain of the Port Zone. 3.05-20 Section 3.05-20 Navigation and Navigable... INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES First Coast Guard District § 3.05-20 Sector Southeastern New England Marine Inspection Zone and Captain of the Port Zone. Sector Southeastern New England's office is...

  19. 33 CFR 3.05-20 - Sector Southeastern New England Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Marine Inspection Zone and Captain of the Port Zone. 3.05-20 Section 3.05-20 Navigation and Navigable... INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES First Coast Guard District § 3.05-20 Sector Southeastern New England Marine Inspection Zone and Captain of the Port Zone. Sector Southeastern New England's office is...

  20. 33 CFR 3.05-20 - Sector Southeastern New England Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Marine Inspection Zone and Captain of the Port Zone. 3.05-20 Section 3.05-20 Navigation and Navigable... INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES First Coast Guard District § 3.05-20 Sector Southeastern New England Marine Inspection Zone and Captain of the Port Zone. Sector Southeastern New England's office is...

  1. 33 CFR 3.05-20 - Sector Southeastern New England Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Marine Inspection Zone and Captain of the Port Zone. 3.05-20 Section 3.05-20 Navigation and Navigable... INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES First Coast Guard District § 3.05-20 Sector Southeastern New England Marine Inspection Zone and Captain of the Port Zone. Sector Southeastern New England's office is...

  2. 33 CFR 3.05-20 - Sector Southeastern New England Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Marine Inspection Zone and Captain of the Port Zone. 3.05-20 Section 3.05-20 Navigation and Navigable... INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES First Coast Guard District § 3.05-20 Sector Southeastern New England Marine Inspection Zone and Captain of the Port Zone. Sector Southeastern New England's office is...

  3. 78 FR 5717 - Safety Zone; Military Ocean Terminal Concord Safety Zone, Suisun Bay, Military Ocean Terminal...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-28

    ...-AA00 Safety Zone; Military Ocean Terminal Concord Safety Zone, Suisun Bay, Military Ocean Terminal... Guard is establishing a safety zone in the navigable waters of Suisun Bay near Military Ocean Terminal Concord, CA in support of military onload and offload operations. This safety zone is established to...

  4. 33 CFR 147.847 - Safety Zone; BW PIONEER Floating Production, Storage, and Offloading System Safety Zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety Zone; BW PIONEER Floating... ZONES § 147.847 Safety Zone; BW PIONEER Floating Production, Storage, and Offloading System Safety Zone. (a) Description. The BW PIONEER, a Floating Production, Storage and Offloading (FPSO) system, is in...

  5. 33 CFR 3.05-35 - Sector Long Island Sound Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.05-35 Section 3.05-35 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES First Coast Guard District § 3.05-35 Sector Long Island Sound Marine Inspection Zone and Captain of the Port Zone. Sector Long Island Sound's office is located in New...

  6. 33 CFR 3.05-35 - Sector Long Island Sound Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.05-35 Section 3.05-35 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES First Coast Guard District § 3.05-35 Sector Long Island Sound Marine Inspection Zone and Captain of the Port Zone. Sector Long Island Sound's office is located in New...

  7. 33 CFR 3.05-35 - Sector Long Island Sound Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.05-35 Section 3.05-35 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES First Coast Guard District § 3.05-35 Sector Long Island Sound Marine Inspection Zone and Captain of the Port Zone. Sector Long Island Sound's office is located in New...

  8. 33 CFR 3.05-35 - Sector Long Island Sound Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.05-35 Section 3.05-35 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES First Coast Guard District § 3.05-35 Sector Long Island Sound Marine Inspection Zone and Captain of the Port Zone. Sector Long Island Sound's office is located in New...

  9. 33 CFR 3.05-35 - Sector Long Island Sound Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Inspection Zone and Captain of the Port Zone. 3.05-35 Section 3.05-35 Navigation and Navigable Waters COAST... ZONES, AND CAPTAIN OF THE PORT ZONES First Coast Guard District § 3.05-35 Sector Long Island Sound Marine Inspection Zone and Captain of the Port Zone. Sector Long Island Sound's office is located in New...

  10. Analysis of free zone electrophoresis of fixed erythrocytes performed in microgravity

    NASA Technical Reports Server (NTRS)

    Snyder, Robert S.; Rhodes, Percy H.; Herren, Blair J.; Miller, Teresa Y.; Seaman, Geoffrey V. F.

    1985-01-01

    A free fluid zone electrophoresis experiment was performed in the microgravity environment of Space Shuttle flight STS-3 (March 1983). The experiment was designed to confirm observations made on the Apollo-Soyuz mission of 1975 and to test the effect of high red blood cell (RBC) concentration on free fluid electrophoresis. Photographic documentation of cell zone progression in one-hour separations of mixtures of formaldehyde-fixed human and rabbit erythrocytes, which were subjected to a field of approximately 13 V/cm in low ionic strength buffer, was analyzed. One of two columns contained 2 x 10 to the 8th RBC/ml; (low concentration), and the other contained 1 x 10 to the 9th RBC/ml (high concentration). The observed and calculated leading edge displacements of the RBC in the two columns were in agreement, indicating the absence of unexpected effects of the reduced gravity environment. Post-flight analyses of the contents of the columns was not possible, and additional microgravity experiments are needed to evaluate the role of particle-particle interactions in concentrated suspensions undergoing electrophoresis.

  11. 33 CFR 165.1141 - Safety Zone; San Clemente 3 NM Safety Zone, San Clemente Island, CA.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Guard District § 165.1141 Safety Zone; San Clemente 3 NM Safety Zone, San Clemente Island, CA. (a) Location. The following area is a safety zone: All waters of the Pacific Ocean surrounding San Clemente... Safety Zone, San Clemente Island, CA. 165.1141 Section 165.1141 Navigation and Navigable Waters COAST...

  12. 33 CFR 165.1141 - Safety Zone; San Clemente 3 NM Safety Zone, San Clemente Island, CA.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Guard District § 165.1141 Safety Zone; San Clemente 3 NM Safety Zone, San Clemente Island, CA. (a) Location. The following area is a safety zone: All waters of the Pacific Ocean surrounding San Clemente... Safety Zone, San Clemente Island, CA. 165.1141 Section 165.1141 Navigation and Navigable Waters COAST...

  13. 33 CFR 165.1141 - Safety Zone; San Clemente 3 NM Safety Zone, San Clemente Island, CA.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Guard District § 165.1141 Safety Zone; San Clemente 3 NM Safety Zone, San Clemente Island, CA. (a) Location. The following area is a safety zone: All waters of the Pacific Ocean surrounding San Clemente... Safety Zone, San Clemente Island, CA. 165.1141 Section 165.1141 Navigation and Navigable Waters COAST...

  14. 33 CFR 165.1141 - Safety Zone; San Clemente 3 NM Safety Zone, San Clemente Island, CA.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Guard District § 165.1141 Safety Zone; San Clemente 3 NM Safety Zone, San Clemente Island, CA. (a) Location. The following area is a safety zone: All waters of the Pacific Ocean surrounding San Clemente... Safety Zone, San Clemente Island, CA. 165.1141 Section 165.1141 Navigation and Navigable Waters COAST...

  15. 33 CFR 165.1141 - Safety Zone; San Clemente 3 NM Safety Zone, San Clemente Island, CA.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Guard District § 165.1141 Safety Zone; San Clemente 3 NM Safety Zone, San Clemente Island, CA. (a) Location. The following area is a safety zone: All waters of the Pacific Ocean surrounding San Clemente... Safety Zone, San Clemente Island, CA. 165.1141 Section 165.1141 Navigation and Navigable Waters COAST...

  16. 76 FR 41073 - Security Zones; Sector Southeastern New England Captain of the Port Zone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-13

    .... ACTION: Final rule. SUMMARY: The Coast Guard is establishing security zones around cruise ships in the... creates security zones for all navigable waters around certain cruise ships in the Southeastern New... temporary security zone regulation in Sec. 165.T01-0864. On April 5, 2011, we published a notice of proposed...

  17. Lenalidomide And Rituximab as Maintenance Therapy in Treating Patients With B-Cell Non-Hodgkin Lymphoma

    ClinicalTrials.gov

    2015-11-25

    Adult Non-Hodgkin Lymphoma; Adult Grade III Lymphomatoid Granulomatosis; Contiguous Stage II Adult Burkitt Lymphoma; Contiguous Stage II Adult Diffuse Large Cell Lymphoma; Contiguous Stage II Adult Diffuse Mixed Cell Lymphoma; Contiguous Stage II Adult Diffuse Small Cleaved Cell Lymphoma; Contiguous Stage II Adult Immunoblastic Large Cell Lymphoma; Contiguous Stage II Adult Lymphoblastic Lymphoma; Contiguous Stage II Grade 1 Follicular Lymphoma; Contiguous Stage II Grade 2 Follicular Lymphoma; Contiguous Stage II Grade 3 Follicular Lymphoma; Contiguous Stage II Mantle Cell Lymphoma; Contiguous Stage II Marginal Zone Lymphoma; Contiguous Stage II Small Lymphocytic Lymphoma; Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Nodal Marginal Zone B-cell Lymphoma; Noncontiguous Stage II Adult Burkitt Lymphoma; Noncontiguous Stage II Adult Diffuse Large Cell Lymphoma; Noncontiguous Stage II Adult Diffuse Mixed Cell Lymphoma; Noncontiguous Stage II Adult Diffuse Small Cleaved Cell Lymphoma; Noncontiguous Stage II Adult Immunoblastic Large Cell Lymphoma; Noncontiguous Stage II Adult Lymphoblastic Lymphoma; Noncontiguous Stage II Grade 1 Follicular Lymphoma; Noncontiguous Stage II Grade 2 Follicular Lymphoma; Noncontiguous Stage II Grade 3 Follicular Lymphoma; Noncontiguous Stage II Mantle Cell Lymphoma; Noncontiguous Stage II Marginal Zone Lymphoma; Noncontiguous Stage II Small Lymphocytic Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent

  18. Plerixafor and Filgrastim For Mobilization of Donor Peripheral Blood Stem Cells Before A Donor Peripheral Blood Stem Cell Transplant in Treating Patients With Hematologic Malignancies

    ClinicalTrials.gov

    2017-06-26

    Accelerated Phase Chronic Myelogenous Leukemia; Adult Acute Lymphoblastic Leukemia in Remission; Adult Acute Myeloid Leukemia in Remission; Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Atypical Chronic Myeloid Leukemia, BCR-ABL Negative; Blastic Phase Chronic Myelogenous Leukemia; Chronic Phase Chronic Myelogenous Leukemia; de Novo Myelodysplastic Syndromes; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Myelodysplastic/Myeloproliferative Neoplasm, Unclassifiable; Nodal Marginal Zone B-cell Lymphoma; Noncontiguous Stage II Adult Burkitt Lymphoma; Noncontiguous Stage II Adult Diffuse Large Cell Lymphoma; Noncontiguous Stage II Adult Diffuse Mixed Cell Lymphoma; Noncontiguous Stage II Adult Diffuse Small Cleaved Cell Lymphoma; Noncontiguous Stage II Adult Immunoblastic Large Cell Lymphoma; Noncontiguous Stage II Adult Lymphoblastic Lymphoma; Noncontiguous Stage II Grade 1 Follicular Lymphoma; Noncontiguous Stage II Grade 2 Follicular Lymphoma; Noncontiguous Stage II Grade 3 Follicular Lymphoma; Noncontiguous Stage II Mantle Cell Lymphoma; Noncontiguous Stage II Marginal Zone Lymphoma; Noncontiguous Stage II Small Lymphocytic Lymphoma; Previously Treated Myelodysplastic Syndromes; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Cutaneous T-cell Non-Hodgkin Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular

  19. Iodine I 131 Tositumomab, Etoposide and Cyclophosphamide Followed by Autologous Stem Cell Transplant in Treating Patients With Relapsed or Refractory Non-Hodgkin's Lymphoma

    ClinicalTrials.gov

    2017-07-21

    Anaplastic Large Cell Lymphoma; Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Nodal Marginal Zone B-cell Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Splenic Marginal Zone Lymphoma; Waldenström Macroglobulinemia

  20. Reading First Coordinates from the Nephrogenic Zone in Human Fetal Kidney.

    PubMed

    Minuth, Will W

    2018-01-01

    While substantial information is available on organ anlage and the primary formation of nephrons, molecular mechanisms acting during the late development of the human kidney have received an astonishing lack of attention. In healthy newborn babies, nephrogenesis takes place unnoticed until birth. Upon delivery, morphogenetic activity in the nephrogenic zone decreases, and the stem cell niches aligned beyond the organ capsule vanish by an unknown signal. However, this signal also plays a key role in preterm and low birth weight babies. Although they are born in a phase of active nephrogenesis, pathological findings illustrate that they evolve to a high incidence oligonephropathy and prematurity of renal parenchyma. Different extra- and intrauterine influences seem to be responsible, but independent from chemical nature, all of them culminate in the nephrogenic zone. One assumes that the marred development is caused either by an overshoot of metabolites, misleading signaling of morphogens, unbalanced synthesis of extracellular matrix or restricted contact between mesenchymal and epithelial stem cells. Even more surprising is that there is only a few vague morphological information of the nephrogenic zone in the human fetal kidney available and ultrastructural data is severely lacking. On this account, the first coordinates were determined by optical microscopy and morphometry. Without claiming to be complete, generated results made it possible to create schematic illustrations true to scale for orientation. It will help graduating students, young pediatricians, pathologists, and scientists working in the field of biomedicine to interpret professionally the nephrogenic zone and contained niches. © 2017 S. Karger AG, Basel.