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41.
Christina Krabbe† Elise Courtois‡ Pia Jensen Jesper R. Jørgensen† Jens Zimmer Alberto Martínez-Serrano‡ Morten Meyer 《Journal of neurochemistry》2009,110(6):1908-1920
Neural stem cells constitute a promising source of cells for transplantation in Parkinson's disease, but a protocol for controlled dopaminergic differentiation is not yet available. Here we investigated the effect of the anti-apoptotic protein Bcl-xL and oxygen tension on dopaminergic differentiation and survival of a human ventral mesencephalic stem cell line (hVM1). hVM1 cells and a Bcl-xL over-expressing subline (hVMbcl-xL ) were differentiated by sequential treatment with fibroblast growth factor-8, forskolin, sonic hedgehog, and glial cell line-derived neurotrophic factor. After 10 days at 20% oxygen, hVMbcl-xL cultures contained proportionally more tyrosine hydroxylase(TH)-positive cells than hVM1 control cultures. This difference was significantly potentiated from 11 ± 0.8% to 17.2 ± 0.2% of total cells when the oxygen tension was lowered to 3%. Immunocytochemistry and Q-PCR-analysis revealed expression of several dopaminergic markers besides of TH just as dopamine was detected in the culture medium by HPLC analysis. Although Bcl-xL -over-expression reduced cell death in the cultures, it did not alter the relative content of GABAergic, neurons, while the content of astroglial cells was reduced in hVMbcl-xL cell cultures compared with control. We conclude that Bcl-xL and lowered oxygen tension act in concert to enhance dopaminergic differentiation and survival of human neural stem cells. 相似文献
42.
Tobias Ruck Stefanie Bock Steffen Pfeuffer Christina B.Schroeter Derya Cengiz Paul Marciniak Maren Lindner Alexander Herrmann Marie Liebmann Stjepana Kovac Lukas Gola Leoni Rolfes Marc Pawlitzki Nils Opel Tim Hahn Udo Dannlowski Thomas Pap Felix Luessi Julian A.Schreiber Bernhard Wünsch Tanja Kuhlmann Guiscard Seebohm Bjrn Tackenberg Patricia Seja Frank Dring Erhard Wischmeyer Achmet Imam Chasan Johannes Roth Luisa Klotz Gerd Meyer zu Hrste Heinz Wiendl Tobias Marschall Stefan Floess Jochen Huehn Thomas Budde Tobias Bopp Stefan Bittner Sven G.Meuth 《Cell research》2022,32(1):72-88
It remains largely unclear how thymocytes translate relative differences in T cell receptor (TCR) signal strength into distinct developmental programs that driv... 相似文献
43.
A deliberate approach to screening for initial crystallization conditions of biological macromolecules 总被引:4,自引:0,他引:4
Luft JR Collins RJ Fehrman NA Lauricella AM Veatch CK DeTitta GT 《Journal of structural biology》2003,142(1):170-179
A method to rationally predict crystallization conditions for a previously uncrystallized macromolecule has not yet been developed. One way around this problem is to determine initial crystallization conditions by casting a wide net, surveying a large number of chemical and physical conditions to locate crystallization leads. A facility that executes the rapid survey of crystallization lead conditions is described in detail. Results and guidelines for the initial screening of crystallization conditions, applicable to both manual and robotic setups, are discussed. 相似文献
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McKimmie CS Fraser AR Hansell C Gutiérrez L Philipsen S Connell L Rot A Kurowska-Stolarska M Carreno P Pruenster M Chu CC Lombardi G Halsey C McInnes IB Liew FY Nibbs RJ Graham GJ 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(5):3353-3363
D6 scavenges inflammatory chemokines and is essential for the regulation of inflammatory and immune responses. Mechanisms explaining the cellular basis for D6 function have been based on D6 expression by lymphatic endothelial cells. In this study, we demonstrate that functional D6 is also expressed by murine and human hemopoietic cells and that this expression can be regulated by pro- and anti-inflammatory agents. D6 expression was highest in B cells and dendritic cells (DCs). In myeloid cells, LPS down-regulated expression, while TGF-beta up-regulated expression. Activation of T cells with anti-CD3 and soluble CD28 up-regulated mRNA expression 20-fold, while maturation of human macrophage and megakaryocyte precursors also up-regulated D6 expression. Competition assays demonstrated that chemokine uptake was D6 dependent in human leukocytes, whereas mouse D6-null cells failed to uptake and clear inflammatory chemokines. Furthermore, we present evidence indicating that D6 expression is GATA1 dependent, thus explaining D6 expression in myeloid progenitor cells, mast cells, megakaryocytes, and DCs. We propose a model for D6 function in which leukocytes, within inflamed sites, activate D6 expression and thus trigger resolution of inflammatory responses. Our data on D6 expression by circulating DCs and B cells also suggest alternative roles for D6, perhaps in the coordination of innate and adaptive immune responses. These data therefore alter our models of in vivo D6 function and suggest possible discrete, and novel, roles for D6 on lymphatic endothelial cells and leukocytes. 相似文献
46.
Anna U?arowska Giuseppe Dionisio Barbara Sarholz Hans-Peter Piepho Mingliang Xu Christina R?nn Ingvardsen Gerhard Wenzel Thomas Lübberstedt 《BMC plant biology》2009,9(1):15
Background
The potyviruses sugarcane mosaic virus (SCMV) and maize dwarf mosaic virus (MDMV) are major pathogens of maize worldwide. Two loci, Scmv1 and Scmv2, have ealier been shown to confer complete resistance to SCMV. Custom-made microarrays containing previously identified SCMV resistance candidate genes and resistance gene analogs were utilised to investigate and validate gene expression and expression patterns of isogenic lines under pathogen infection in order to obtain information about the molecular mechanisms involved in maize-potyvirus interactions. 相似文献47.
Human immunodeficiency virus-specific CD8+ T-cell activity is detectable from birth in the majority of in utero-infected infants 下载免费PDF全文
Thobakgale CF Ramduth D Reddy S Mkhwanazi N de Pierres C Moodley E Mphatswe W Blanckenberg N Cengimbo A Prendergast A Tudor-Williams G Dong K Jeena P Kindra G Bobat R Coovadia H Kiepiela P Walker BD Goulder PJ 《Journal of virology》2007,81(23):12775-12784
Human immunodeficiency virus (HIV)-infected infants in sub-Saharan Africa typically progress to AIDS or death by 2 years of life in the absence of antiretroviral therapy. This rapid progression to HIV disease has been related to immaturity of the adaptive immune response in infants. We screened 740 infants born to HIV-infected mothers and tracked development and specificity of HIV-specific CD8+ T-cell responses in 63 HIV-infected infants identified using gamma interferon enzyme-linked immunospot assays and intracellular cytokine staining. Forty-four in utero-infected and 19 intrapartum-infected infants were compared to 45 chronically infected children >2 years of age. Seventy percent (14 of 20) in utero-infected infants tested within the first week of life demonstrated HIV-specific CD8+ T-cell responses. Gag, Pol, and Nef were the principally targeted regions in chronic pediatric infection. However, Env dominated the overall response in one-third (12/36) of the acutely infected infants, compared to only 2/45 (4%) of chronically infected children (P = 0.00083). Gag-specific CD4+ T-cell responses were minimal to undetectable in the first 6 months of pediatric infection. These data indicate that failure to control HIV replication in in utero-infected infants is not due to an inability to induce responses but instead suggest secondary failure of adaptive immunity in containing this infection. Moreover, the detection of virus-specific CD8+ T-cell responses in the first days of life in most in utero-infected infants is encouraging for HIV vaccine interventions in infants. 相似文献
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49.
EST-based gene discovery in pig: virtual expression patterns and comparative mapping to human 总被引:3,自引:0,他引:3
Christopher K. Tuggle Jon A. Green Carolyn Fitzsimmons Rami Woods Randall S. Prather Sergei Malchenko Bento M. Soares Tamara Kucaba Keith Crouch Christina Smith Dylan Tack Natalie Robinson Brian O'Leary Todd Scheetz Thomas Casavant Daniel Pomp Brad J. Edeal Yuandan Zhang Max F. Rothschild Kevin Garwood William Beavis 《Mammalian genome》2003,14(8):565-579
A molecular understanding of porcine reproduction is of biological interest and economic importance. Our Midwest Consortium has produced cDNA libraries containing the majority of genes expressed in major female reproductive tissues, and we have deposited into public databases 21,499 expressed sequence tag (EST) gene sequences from the 3 end of clones from these libraries. These sequences represent 10,574 different genes, based on sequence comparison among these data, and comparison with existing porcine ESTs and genes indicate as many as 4652 of these EST clusters are novel. In silico analysis identified sequences that are expressed in specific pig tissues or organs and confirmed the broad expression in pig for many genes ubiquitously expressed in human tissues. Furthermore, we have developed computer software to identify sequence similarity of these pig genes with their human counterparts, and to extract the mapping information of these human homologues from genome databases. We demonstrate the utility of this software for comparative mapping by localizing 61 genes on the porcine physical map for Chromosomes (Chrs) 5, 10, and 14.
The following Accession numbers were assigned to our deposited sequences: BF701840 – BF704551, BF708383, BF708386 – BF713604, BG322266 – BG322271, BI398567 – BI405235, BQ597354 – BQ605166. 相似文献
50.