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101.
102.
Wood K Paz A Dijkstra K Scheek RM Otten R Silman I Sussman JL Mulder FA 《Biomolecular NMR assignments》2012,6(1):15-18
Neuroligins act as heterophilic adhesion molecules at neuronal synapses. Their cytoplasmic domains interact with synaptic
scaffolding proteins, and have been shown to be intrinsically disordered. Here we report the backbone and side chain 1H, 13C and 15N resonance assignments for the cytoplasmic domain of human neuroligin 3. 相似文献
103.
Lindsay A. Bliss Malik R. Sams Amy Deep-Soboslay Renee Ren-Patterson Andrew E. Jaffe Josh G. Chenoweth Amritha Jaishankar Joel E. Kleinman Thomas M. Hyde 《PloS one》2012,7(9)
Fibroblasts can be collected from deceased individuals, grown in culture, reprogrammed into induced pluripotent stem cells (iPSCs), and then differentiated into a multitude of cell types, including neurons. Past studies have generated iPSCs from somatic cell biopsies from either animal or human subjects. Previously, fibroblasts have only been successfully cultured from postmortem human skin in two studies. Here we present data on fibroblast cell cultures generated from 146 scalp and/or 53 dura mater samples from 146 postmortem human brain donors. In our overall sample, the odds of successful dural culture was almost two-fold compared with scalp (OR = 1.95, 95% CI: [1.01, 3.9], p = 0.047). Using a paired design within subjects for whom both tissues were available for culture (n = 53), the odds of success for culture in dura was 16-fold as compared to scalp (OR = 16.0, 95% CI: [2.1–120.6], p = 0.0007). Unattended death, tissue donation source, longer postmortem interval (PMI), and higher body mass index (BMI) were associated with unsuccessful culture in scalp (all p<0.05), but not in dura. While scalp cells proliferated more and grew more rapidly than dura cells [F (1, 46) = 12.94, p<0.008], both tissues could be generated and maintained as fibroblast cell lines. Using a random sample of four cases, we found that both postmortem scalp and dura could be successfully reprogrammed into iPSC lines. Our study demonstrates that postmortem dura mater, and to a lesser extent, scalp, are viable sources of living fibroblasts for culture that can be used to generate iPSCs. These tissues may be accessible through existing brain tissue collections, which is critical for studying disorders such as neuropsychiatric diseases. 相似文献
104.
Kazuhiro Kawamura Yuan Chen Yimin Shu Yuan Cheng Jie Qiao Barry Behr Renee A. Reijo. Pera Aaron J. W. Hsueh 《PloS one》2012,7(11)
Studies using animal models demonstrated the importance of autocrine/paracrine factors secreted by preimplantation embryos and reproductive tracts for embryonic development and implantation. Although in vitro fertilization-embryo transfer (IVF-ET) is an established procedure, there is no evidence that present culture conditions are optimal for human early embryonic development. In this study, key polypeptide ligands known to be important for early embryonic development in animal models were tested for their ability to improve human early embryo development and blastocyst outgrowth in vitro. We confirmed the expression of key ligand/receptor pairs in cleavage embryos derived from discarded human tri-pronuclear zygotes and in human endometrium. Combined treatment with key embryonic growth factors (brain-derived neurotrophic factor, colony-stimulating factor, epidermal growth factor, granulocyte macrophage colony-stimulating factor, insulin-like growth factor-1, glial cell-line derived neurotrophic factor, and artemin) in serum-free media promoted >2.5-fold the development of tri-pronuclear zygotes to blastocysts. For normally fertilized embryos, day 3 surplus embryos cultured individually with the key growth factors showed >3-fold increases in the development of 6–8 cell stage embryos to blastocysts and >7-fold increase in the proportion of high quality blastocysts based on Gardner’s criteria. Growth factor treatment also led to a 2-fold promotion of blastocyst outgrowth in vitro when day 7 surplus hatching blastocysts were used. When failed-to-be-fertilized oocytes were used to perform somatic cell nuclear transfer (SCNT) using fibroblasts as donor karyoplasts, inclusion of growth factors increased the progression of reconstructed SCNT embryos to >4-cell stage embryos. Growth factor supplementation of serum-free cultures could promote optimal early embryonic development and implantation in IVF-ET and SCNT procedures. This approach is valuable for infertility treatment and future derivation of patient-specific embryonic stem cells. 相似文献
105.
Background aimsInfluenza viruses cause potentially fatal respiratory infections in stem cell transplant patients. Specific T cells provide long-lived host adaptive immunity to influenza viruses, and the potential for generating such cells for clinical use was investigatedMethodsThe inactivated influenza vaccine (Fluvax) approved for human use was used as the antigen source. Monocyte-derived dendritic cells pulsed with Fluvax were used to stimulate autologous peripheral blood mononuclear cells (PBMC) on days 0 and 7. Cells were expanded with interleukin (IL)-2 from day 7 onwards. Cell numbers and phenotype were assessed on day 21. The presence of influenza virus-specific cells was assessed by cytokine production and proliferative responses following restimulation with influenza antigensResultsOver 21 days of culture, a mean fold increase of 26.3 in cell number was observed (n = 7). Cultures were predominantly effector and central memory CD4+ cells, and expressed a phenotype characteristic of activated antigen-specific cells capable of B-cell helper function. Cytotoxic CD4+ and CD8+ cells specific for influenza and a high percentage of CD4+ cells specific for each of three influenza viruses targeted by Fluvax (H1N1, H3N2 and Brisbane viruses) were generated. In addition, T cells expanded when restimulated with antigens derived from influenza viruses.ConclusionsWe have demonstrated a clinically usable method for producing influenza virus-specific T cells that yield high numbers of highly reactive CD4+ cells suitable for adoptive immunotherapy. We propose that reconstructing host immunity through adoptive transfer of influenza virus-specific T cells will reduce the frequency of influenza-related deaths in the period of severe immune suppression that follows stem cell transplantation. 相似文献
106.
Carmela Guido Diana Whitaker-Menezes Claudia Capparelli Renee Balliet Zhao Lin Richard G. Pestell Anthony Howell Saveria Aquila Sebastiano Andò Ubaldo Martinez-Outschoorn Federica Sotgia Michael P. Lisanti 《Cell cycle (Georgetown, Tex.)》2012,11(16):3019-3035
We have previously shown that a loss of stromal Cav-1 is a biomarker of poor prognosis in breast cancers. Mechanistically, a loss of Cav-1 induces the metabolic reprogramming of stromal cells, with increased autophagy/mitophagy, mitochondrial dysfunction and aerobic glycolysis. As a consequence, Cav-1-low CAFs generate nutrients (such as L-lactate) and chemical building blocks that fuel mitochondrial metabolism and the anabolic growth of adjacent breast cancer cells. It is also known that a loss of Cav-1 is associated with hyperactive TGF-β signaling. However, it remains unknown whether hyperactivation of the TGF-β signaling pathway contributes to the metabolic reprogramming of Cav-1-low CAFs. To address these issues, we overexpressed TGF-β ligands and the TGF-β receptor I (TGFβ-RI) in stromal fibroblasts and breast cancer cells. Here, we show that the role of TGF-β in tumorigenesis is compartment-specific, and that TGF-β promotes tumorigenesis by shifting cancer-associated fibroblasts toward catabolic metabolism. Importantly, the tumor-promoting effects of TGF-β are independent of the cell type generating TGF-β. Thus, stromal-derived TGF-β activates signaling in stromal cells in an autocrine fashion, leading to fibroblast activation, as judged by increased expression of myofibroblast markers, and metabolic reprogramming, with a shift toward catabolic metabolism and oxidative stress. We also show that TGF-β-activated fibroblasts promote the mitochondrial activity of adjacent cancer cells, and in a xenograft model, enhancing the growth of breast cancer cells, independently of angiogenesis. Conversely, activation of the TGF-β pathway in cancer cells does not influence tumor growth, but cancer cell-derived-TGF-β ligands affect stromal cells in a paracrine fashion, leading to fibroblast activation and enhanced tumor growth. In conclusion, ligand-dependent or cell-autonomous activation of the TGF-β pathway in stromal cells induces their metabolic reprogramming, with increased oxidative stress, autophagy/mitophagy and glycolysis, and downregulation of Cav-1. These metabolic alterations can spread among neighboring fibroblasts and greatly sustain the growth of breast cancer cells. Our data provide novel insights into the role of the TGF-β pathway in breast tumorigenesis, and establish a clear causative link between the tumor-promoting effects of TGF-β signaling and the metabolic reprogramming of the tumor microenvironment. 相似文献
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108.
109.
Soler Bistué AJ Birshan D Tomaras AP Dandekar M Tran T Newmark J Bui D Gupta N Hernandez K Sarno R Zorreguieta A Actis LA Tolmasky ME 《PloS one》2008,3(3):e1800
Background
Dissemination of antimicrobial resistance genes has become an important public health and biodefense threat. Plasmids are important contributors to the rapid acquisition of antibiotic resistance by pathogenic bacteria.Principal Findings
The nucleotide sequence of the Klebsiella pneumoniae multiresistance plasmid pMET1 comprises 41,723 bp and includes Tn1331.2, a transposon that carries the bla TEM-1 gene and a perfect duplication of a 3-kbp region including the aac(6′)-Ib, aadA1, and bla OXA-9 genes. The replication region of pMET1 has been identified. Replication is independent of DNA polymerase I, and the replication region is highly related to that of the cryptic Yersinia pestis 91001 plasmid pCRY. The potential partition region has the general organization known as the parFG locus. The self-transmissible pMET1 plasmid includes a type IV secretion system consisting of proteins that make up the mating pair formation complex (Mpf) and the DNA transfer (Dtr) system. The Mpf is highly related to those in the plasmid pCRY, the mobilizable high-pathogenicity island from E. coli ECOR31 (HPIECOR31), which has been proposed to be an integrative conjugative element (ICE) progenitor of high-pathogenicity islands in other Enterobacteriaceae including Yersinia species, and ICEKp1, an ICE found in a K. pneumoniae strain causing primary liver abscess. The Dtr MobB and MobC proteins are highly related to those of pCRY, but the endonuclease is related to that of plasmid pK245 and has no significant homology with the protein of similar function in pCRY. The region upstream of mobB includes the putative oriT and shares 90% identity with the same region in the HPIECOR31.Conclusions
The comparative analyses of pMET1 with pCRY, HPIECOR31, and ICEKp1 show a very active rate of genetic exchanges between Enterobacteriaceae including Yersinia species, which represents a high public health and biodefense threat due to transfer of multiple resistance genes to pathogenic Yersinia strains. 相似文献110.