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41.
42.
Spleen antibacterial peptides: high levels of PR-39 and presence of two forms of NK-lysin 总被引:1,自引:0,他引:1
Bonetto V Andersson M Bergman T Sillard R Norberg A Mutt V Jornvall H 《Cellular and molecular life sciences : CMLS》1999,56(1-2):174-178
Antibacterial peptides were isolated from porcine spleen by acetic acid extraction, ion exchange chromatography and reverse-phase high-performance liquid chromatography. C-terminal ladder sequence analysis of a bioactive peptide with matrix-assisted laser desorption/ionization mass spectrometry after digestion with carboxypeptidases P and Y showed that it is identical to the antibacterial proline/arginine-rich intestinal peptide PR-39. It is present at high levels in granulocytes of the spleen, and peptides with C-terminal proline amide and internal adjacent Pro residues can be analyzed with this method. In addition, two forms of NK-lysin (NKL) were found. One, NKLi, is identical to that isolated from pig intestine, and the other, NKLbw, to a mature peptide deduced from a clone from a porcine bone marrow cDNA library. 相似文献
43.
44.
Functional and biochemical characteristics of mitochondrial fractions from rat liver in cold-induced oxidative stress 总被引:2,自引:0,他引:2
Venditti P De Rosa R Caldarone G Di Meo S 《Cellular and molecular life sciences : CMLS》2004,61(24):3104-3116
We determined characteristics of rat liver mitochondrial fractions, resolved at 1000 (M1), 3000 (M3), and 10,000 g (M10) after 2 and 10 days cold exposure. In all groups, the M1 fraction exhibited the highest oxidative capacity, oxidative damage, H2O2 production rate, and susceptibility to stress conditions, and the lowest antioxidant levels. Cold exposure increased cytochrome oxidase activity in all fractions and succinate-supported O2 consumption in the M1 and M10 fractions during state 3 and state 4 respiration, respectively. With succinate, the H2O2 release rate increased in all fractions during state 4 and state 3 respiration, whereas with pyruvate/malate, it increased only during state 4 respiration. Increases in tissue mitochondrial proteins caused a faster H2O2 flow from the mitochondrial to cytosolic compartment, which was limited by the reduction in the M1 fraction. Despite increased liposoluble antioxidant levels, cold also caused enhanced oxidative damage and susceptibility to oxidative challenge and Ca2+-induced swelling in all fractions. These changes leading to elimination of H2O2-overproducing mitochondria avoided excessive tissue damage. We propose that triiodothyronine, whose levels increase in the cold environment, brings about the biochemical changes producing oxidative damage and those limiting its extent.Received 16 July 2004; received after revision 27 September 2004; accepted 18 October 2004 相似文献
45.
Role of nitric oxide in the functional response to ischemia-reperfusion of heart mitochondria from hyperthyroid rats 总被引:2,自引:0,他引:2
Venditti P De Rosa R Cigliano L Agnisola C Di Meo S 《Cellular and molecular life sciences : CMLS》2004,61(17):2244-2252
We investigated the role of nitric oxide (NO) in the mitochondrial derangement associated with the functional response to ischemia-reperfusion of hyperthyroid rat hearts. Mitochondria were isolated at 3000 g from hearts subjected to ischemia-reperfusion, with or without N-nitro-L-arginine (L-NNA, an NO synthase inhibitor). During reperfusion, hyperthyroid hearts displayed tachycardia and low functional recovery. Their mitochondria exhibited O2 consumption similar to euthyroid controls, while H2O2 production, hydroperoxide, protein-bound carbonyl and nitrotyrosine levels, and susceptibility to swelling were higher. L-NNA blocked the reperfusion tachycardic response and increased inotropic recovery in hyperthyroid hearts. L-NNA decreased mitochondrial H2O2 production and oxidative damage, and increased respiration and tolerance to swelling. Such effects were higher in hyperthyroid preparations. These results confirm the role of mitochondria in ischemia-reperfusion damage, and strongly suggest that NO overproduction is involved in the high mitochondrial dysfunction and the low recovery of hyperthyroid hearts from ischemia-reperfusion. L-NNA also decreased protein content and cytochrome oxidase activity of a mitochondrial fraction isolated at 8000 g. This and previous results suggest that the above fraction contains, together with light mitochondria, damaged mitochondria coming from the heaviest fraction, which has the highest cytochrome oxidase activity and capacity to produce H2O2. Therefore, we propose that the high mitochondrial susceptibility to swelling, favoring mitochondrial population purification from H2O2-overproducing mitochondria, limits hyperthyroid heart oxidative stress.Received 24 March 2004; received after revision 9 June 2004; accepted 5 July 2004 相似文献
46.
Natural killer (NK) cells have originally been identified by their spontaneous cytolytic potential against tumor cells, which,
however, might result from pre-activation due to prior pathogen exposure. Resting NK cells, on the contrary, require activation
by bystander antigen-presenting cells to reach their full functional competence. In this review, we will summarize studies
on how dendritic cells (DCs), the most potent type of antigen-presenting cell, communicate with human NK cells to activate
them in secondary lymphoid organs and to integrate signals from activated NK cells at sites of inflammation for their own
maturation. Furthermore, we will review aspects of the immunological synapse, which mediates this cross-talk. These studies
provide the mechanistic understanding of how mature DCs can activate NK cells and survive to go on for the activation of adaptive
immunity. This feature of DCs, to activate different waves of immune responses, could be harnessed for immunotherapies, including
vaccinations. 相似文献
47.
Mutations in the colony stimulating factor 1 receptor (CSF1R) gene cause hereditary diffuse leukoencephalopathy with spheroids 总被引:1,自引:0,他引:1
Rademakers R Baker M Nicholson AM Rutherford NJ Finch N Soto-Ortolaza A Lash J Wider C Wojtas A DeJesus-Hernandez M Adamson J Kouri N Sundal C Shuster EA Aasly J MacKenzie J Roeber S Kretzschmar HA Boeve BF Knopman DS Petersen RC Cairns NJ Ghetti B Spina S Garbern J Tselis AC Uitti R Das P Van Gerpen JA Meschia JF Levy S Broderick DF Graff-Radford N Ross OA Miller BB Swerdlow RH Dickson DW Wszolek ZK 《Nature genetics》2012,44(2):200-205
Hereditary diffuse leukoencephalopathy with spheroids (HDLS) is an autosomal-dominant central nervous system white-matter disease with variable clinical presentations, including personality and behavioral changes, dementia, depression, parkinsonism, seizures and other phenotypes. We combined genome-wide linkage analysis with exome sequencing and identified 14 different mutations affecting the tyrosine kinase domain of the colony stimulating factor 1 receptor (encoded by CSF1R) in 14 families with HDLS. In one kindred, we confirmed the de novo occurrence of the mutation. Follow-up sequencing identified an additional CSF1R mutation in an individual diagnosed with corticobasal syndrome. In vitro, CSF-1 stimulation resulted in rapid autophosphorylation of selected tyrosine residues in the kinase domain of wild-type but not mutant CSF1R, suggesting that HDLS may result from partial loss of CSF1R function. As CSF1R is a crucial mediator of microglial proliferation and differentiation in the brain, our findings suggest an important role for microglial dysfunction in HDLS pathogenesis. 相似文献
48.
Yamanouchi J Rainbow D Serra P Howlett S Hunter K Garner VE Gonzalez-Munoz A Clark J Veijola R Cubbon R Chen SL Rosa R Cumiskey AM Serreze DV Gregory S Rogers J Lyons PA Healy B Smink LJ Todd JA Peterson LB Wicker LS Santamaria P 《Nature genetics》2007,39(3):329-337
Autoimmune diseases are thought to result from imbalances in normal immune physiology and regulation. Here, we show that autoimmune disease susceptibility and resistance alleles on mouse chromosome 3 (Idd3) correlate with differential expression of the key immunoregulatory cytokine interleukin-2 (IL-2). In order to test directly that an approximately twofold reduction in IL-2 underpins the Idd3-linked destabilization of immune homeostasis, we show that engineered haplodeficiency of Il2 gene expression not only reduces T cell IL-2 production by twofold but also mimics the autoimmune dysregulatory effects of the naturally occurring susceptibility alleles of Il2. Reduced IL-2 production achieved by either genetic mechanism correlates with reduced function of CD4(+) CD25(+) regulatory T cells, which are critical for maintaining immune homeostasis. 相似文献
49.
Quantum continuous variables are being explored as an alternative means to implement quantum key distribution, which is usually based on single photon counting. The former approach is potentially advantageous because it should enable higher key distribution rates. Here we propose and experimentally demonstrate a quantum key distribution protocol based on the transmission of gaussian-modulated coherent states (consisting of laser pulses containing a few hundred photons) and shot-noise-limited homodyne detection; squeezed or entangled beams are not required. Complete secret key extraction is achieved using a reverse reconciliation technique followed by privacy amplification. The reverse reconciliation technique is in principle secure for any value of the line transmission, against gaussian individual attacks based on entanglement and quantum memories. Our table-top experiment yields a net key transmission rate of about 1.7 megabits per second for a loss-free line, and 75 kilobits per second for a line with losses of 3.1 dB. We anticipate that the scheme should remain effective for lines with higher losses, particularly because the present limitations are essentially technical, so that significant margin for improvement is available on both the hardware and software. 相似文献
50.
Comparative analysis of zebrafish bone morphogenetic proteins 2, 4 and 16: molecular and evolutionary perspectives 总被引:1,自引:0,他引:1