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ABSTRACT

Interleukin-23 (IL-23, IL-23p19) is a proinflammatory cytokine in the IL-12-related family. Although inflammatory cells in herniated discs have been shown to contain IL-23, little is known about the presence and role of IL-23 in human disc cells. We analyzed disc specimens for IL-23 localization using immunohistochemistry in control, herniated and non-herniated discs from which annulus fibrosus (annulus) cells were isolated and cultured to identify IL-23 gene expression and production. Microarray analysis was used to assess the expression of IL-23 in disc tissue and in cells exposed to two proinflammatory cytokines, IL-1ß and TNF-α. IL-23 was present in annulus cells at the protein level and its expression was up-regulated significantly in herniated compared to control disc tissue. Direct measurement of medium components confirmed production of IL-23 and its receptor, IL-23R, by annulus cells in vitro. Annulus cells in three-dimensional culture exposed to TNF-α, but not IL-1ß, resulted in significant up-regulation of IL-23 expression compared to control cells. Our findings are evidence for the constitutive presence of IL-23 in the human disc and that its expression in vitro is modified by exposure to TNF-α.  相似文献   

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Activated charcoal is commonly used in tissue culture media. Its addition to culture medium may promote or inhibit in vitro growth, depending on species and tissues used. The effects of activated charcoal may be attributed to establishing a darkened environment; adsorption of undesirable/inhibitory substances; adsorption of growth regulators and other organic compounds, or the release of growth promoting substances present in or adsorbed by activated charcoal.  相似文献   

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The apoptosis program of physiological cell death elicits a range of non-phlogistic homeostatic mechanisms—“recognition, response and removal”—that regulate the microenvironments of normal and diseased tissues via multiple modalities operating over short and long distances. The molecular mechanisms mediate intercellular signaling through direct contact with neighboring cells, release of soluble factors and production of membrane-delimited fragments (apoptotic bodies, blebs and microparticles) that allow for interaction with host cells over long distances. These processes effect the selective recruitment of mononuclear phagocytes and the specific activation of both phagocytic and non-phagocytic cells. While much evidence is available concerning the mechanisms underlying the recognition and responses of phagocytes that culminate in the engulfment and removal of apoptotic cell bodies, relatively little is yet known about the non-phagocytic cellular responses to the apoptosis program. These responses regulate inflammatory and immune cell activation as well as cell fate decisions of proliferation, differentiation and death. Here, we review current knowledge of these processes, considering especially how apoptotic cells condition the microenvironments of normal and malignant tissues. We also discuss how apoptotic cells that persist in the absence of phagocytic clearance exert inhibitory effects over their viable neighbors, paying particular attention to the specific case of cell cultures and highlighting how new cell-corpse-clearance devices—Dead-Cert® Nanoparticles—can significantly improve the efficacy of cell cultures through effective removal of non-viable cells in the absence of phagocytes in vitro.  相似文献   

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Ohne ZusammenfassungDiese Arbeit ist bei der Zoologischen Station in Neapel ausgeführt worden. Es ist mir eine angenchme Pflicht, Herrn Prof.Dohrn und Herrn Prof.Seeeni wegen der freundlichen Unterstützung meiner Arbeit meinen aufrichtigsten Dank zu sagen.  相似文献   

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Cisplatinum [cis-diamminedichloroplatinum(II)] is one of the most active antitumour agents and its effect is mainly due to the formation of cisplatinum-DNA crosslinks. Formation of cisplatinum-DNA intrastrand crosslinks in nucleated white blood cells of patients was measured, both in (pretreatment) samples exposed in vitro and in cells collected immediately after in vivo exposure to cisplatinum. Large interpatient variations were found. The in vitro results showed a linear correlation with the in vivo data (cc=0.91). The in vitro measurements of crosslinks may allow prediction of response and avoidance of toxicity in individual patients.  相似文献   

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Cisplatinum [cis-diamminedichloroplatinum(II)] is one of the most active antitumour agents and its effect is mainly due to the formation of cisplatinum-DNA crosslinks. Formation of cisplatinum-DNA intrastrand crosslinks in nucleated white blood cells of patients was measured, both in (pretreatment) samples exposed in vitro and in cells collected immediately after in vivo exposure to cisplatinum. Large interpatient variations were found. The in vitro results showed a linear correlation with the in vivo data (cc = 0.91). The in vitro measurements of crosslinks may allow prediction of response and avoidance of toxicity in individual patients.  相似文献   

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The possible involvement of arachidonic acid (AA) or its metabolites in β-adrenoceptor desensitization has been studied in rat lung parenchyma both from a functional and a biochemical point of view. In vitro perfusion of rat lungs with AA (3×10?5M for 20 min) reduced the relaxant effect of isoproterenol (ISO) on lung parenchymal strips, shown by a shift to the right of ISO dose-response curve, similar to that obtained using desensitizing concentration of specific β-agonist. Moreover, AA treatment reduced the capacity of ISO to stimulate adenylate-cyclase activity, whereas the number of β-receptor binding sites was not significantly modified. Inhibition of cyclo-oxygenase pathway by indomethacin (INDO) (1.5 × 10?5M) prevented both the loss of ISO-relaxing capacity and the decrease of adenylate-cyclase activity induced by AA treatment. In order to support the role of eicosanoids in β-adrenoceptor desensitization, changes of endogenous free AA levels have also been studied in lung homogenates. Perfusion of rat lung with ISO (10?6M for 20 min) decreased by about 50% the levels of free AA and the pretreatment with BW755C (9×10?5M), a lipo- and cyclo-oxygenase inhibitor, prevented this phenomenon. On the basis of these results, we suggest that the activation of AA cascade is actually involved in β-adrenoceptor desensitization in lung tissues with a possible interference at the site beyond the drug-receptor interaction.  相似文献   

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Coffee is an important plantation crop grown in about 80 countries across the globe. In recent years, coffee attained lot of attention in the biotechnology research area. Since last three decades, there has been a steady flow of information on coffee biotechnology and now it is entering into the genomic era. Major milestones in coffee biotech research are successful in vitro manipulation and multiplication of coffee, development of gene transfer protocols and generation of transgenic coffee plants with specific traits. The isolation of genes involved in caffeine biosynthetic pathway has opened up new avenues for generating caffeine free transgenic coffee. With the initiation of international coffee genomics initiatives, the genomic research in coffee is expected to reach new dimensions. The IPR issues may play crucial role in sharing of benefits during international collaborations in near future. This review focuses on the basic and applied aspects of coffee biotechnology for newer potentials.  相似文献   

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Zusammenfassung Die Nucleinsäuren der Grobpartikelfraktion (Sediment 30 000 g) von Chlorella stimulieren den Aminosäure-Einbau im zellfreien, Proteinsynthetisierenden System desselben Organismus. Auftrennung dieser Nucleinsäuren im Rohrzucker-Dichtegradienten ergibt unterschiedliche Stimulierung des Einbaus durch die einzelnen RNA-Komponenten. Die stärkste Förderung wird mit einer niedermolekularen RNA erreicht, die zwischen der löslichen und der leichteren ribosomalen RNA sedimentiert und die nicht mit transfer-RNA identisch ist.
Stimulation of amino acid incorporation in vitro by low molecular weight RNA in Chlorella
Summary The nucleic acids of the particle-fraction (pellet 30,000 g) of Chlorella enhance the amino acid incorporation in vitro in cell-free systems of the same organism.After sucrose density gradient centrifugation, the most stimulating RNA component is found to be a low molecular weight RNA sedimenting between the soluble RNA and the smaller ribosomal RNA component. This stimulating RNA is not identical with transfer-RNA.


Herrn Professor Dr. Richard Harder zum 80. Geburtstag gewidmet.  相似文献   

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Genetic transformation of peppermint is known to be very difficult essentially because of low efficiency regeneration. A regeneration protocol allowing 51% shooting frequency is proposed. Transient -glucuronidase expression and adjustment of selection pressure with kanamycin are also reported. The final retained method to attempt peppermint transformation is:Agrobacterium inoculation or biolistic treatment of the first apical leaves ofin vitro clones, regeneration in the dark with kanamycin (1 mg l–1) and 6-benzylaminopurine (2 mg l–1), followed by selection of regenerated shoots with 200 mg 1–1 kanamycin.Abbreviations BA 6-benzylaminopurine - GUS -glucuronidase - MS Murashige and Skoog (1962) - NAA -naphthalenacetic acid - PIG particle inflow gun - SEM scanning electron microscope  相似文献   

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Asymbiotic germination of immature seeds (embryos), and mature seeds and micropropagation of Spathoglottis plicata were described. Effects of three nutrition media namely, Murashige & Skoog (MS); Phytamax (PM); and Phyto-Technology orchid seed sowing medium (P723), two carbon sources such as glucose and sucrose at 2–3% (w/v), two plant growth regulators such as 6-benzylaminopurine (BAP; 0.5–3.0 mg l 1) and α-naphthalene acetic acid (NAA; 0.5–2.0 mg l 1) and peptone (2.0 g l 1) were examined on seed germination, early protocorm development and micropropagation. The maximum germination of mature seeds (95%) was recorded in PM medium supplemented with 2% (w/v) sucrose + 2.0 g l 1 peptone. For germination of embryos P723 medium supplemented with 1.0 mg l 1 BAP proved best. Multiple shoot buds or protocorm-like bodies (PLBs) were produced from stem segments of in vitro raised seedlings. Both direct organogenesis and embryogenesis were observed and the morphogenetic response was initiated by different concentrations and combinations of PGRs. The optimum PGR combination for maximal PLB regeneration was 1.0 mg l 1 NAA + 2.5 mg l 1 BAP, while 1.0 mg l 1 NAA + 1.0 mg l 1 BAP for shoot bud development. Strong and stout root system was induced in half strength PM medium supplemented with 0.5 mg l 1 IAA. The well-rooted plantlets were transferred to pots containing a potting mixture composed of saw dust, coconut coir, humus, and coal pieces at 1:1:1:2 (w/w) with 80% survival in outside environment and flowered after two years of transfer.  相似文献   

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Inbreeding has been associated with the impairment of reproductive performance in many cattle breeds. Although the usage of reproductive biotechnologies has been increasing in bovine populations, not much attention has been given to the impact of inbreeding over cow’s performance on artificial reproduction. The objective of this study was to estimate the impact of inbreeding on in vitro embryo production in a Guzerá breed population. The inbreeding coefficient (F), calculated as half of the co-ancestry of the individual’s parents, was used as an estimate of inbreeding. The inbreeding coefficients of the donor, sire (used on in vitro fertilization) and of the embryos were included, separately, in the proposed models either as classificatory or continuous variables (linear and quadratic effects). The percentage of non-inbred individuals (or embryos) and mean F of donors, embryos and sires were 29.38%; 35.76%; 42.86% and 1.98±2.68; 1.32±3.13; 2.08±2.79, respectively. Two different models were considered, one for oocyte production traits and other for embryo production traits. The increase of F of the donor significantly (P<0.05) impaired the number of viable oocytes (NOV), number of grade I oocytes (NGI) and number of cleaved embryos (NCLV). Moreover, the donor’s F influenced the percentage of grade I oocytes (PGI), percentage of viable embryos (PEMB) and percentage of cleaved embryos that turned into embryos (PCXE). No significant (P>0.05) effects were observed for the sire (father of the embryos) inbreeding coefficient over the traits analysed. Embryo’s F influenced (P<0.05) the number of viable embryos (NEMB), percentage of viable embryos (PEMB) and percentage of cleaved embryos that turn into embryos (PCXE). Results suggested that an increase in the inbreeding coefficient might impair the embryos ability to survive through challenges imposed by the in vitro environment. Submitting highly inbred Guzerá female donors to in vitro embryo production may, in the long-term, have negative implications on the number of embryos obtained per cow and increase the relative costs of the improvement programmes based on this technology. High levels of inbreeding should be avoided when selecting Guzerá female donors and planning in vitro fertilization mating.  相似文献   

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 Germinating pollen from larch (Larix occidentalis), Sitka spruce (Picea sitchensis) and white pine (Pinus monticola) were co-cultured with megagametophytes dissected from cones of other genera (Pseudotsuga menziesii, Larix×eurolepis and Pinus monticola). Pollen was presented to megagametophytes possessing archegonia which were either alive, degenerating or dead. In addition, pollen was presented to fertilized megagametophytes and to megagametophytes that had been cut in half. Megagametophyte penetration by pollen tubes and male gamete release into archegonia were verified by serial sections of glycomethacrylate-embedded specimens. Pollen tubes penetrated through any part of the apex of the megagametophyte. Division of the body cell into the two gametes was regularly observed. Delivery of gametes was confirmed between spruce and larch. Pollen tubes also penetrated fertilized megagametophytes, dead or degenerating archegonia as well as wounded and/or cut surfaces. This demonstrates the inability of the male gametophyte to optimize its mating efforts, since it is unable to differentiate between healthy and unhealthy archegonia. The megagametophyte cells are unable to optimize male selection. They may produce secretions of a generally attractive nature, as pollen is attracted to the apex of the megagametophyte, but archegonia themselves do not produce pollen-specific signals of either a promotive or inhibitory nature. These results open new avenues for the development of novel breeding strategies where natural breeding barriers may be bypassed. Received: 19 March 1998 / Accepted: 29 April 1998  相似文献   

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Trehalose is a stress protecting and reserve carbohydrate in a variety of organisms. The effect of trehalose on micropropagation of jojoba [Simmondsia chinensis (Link) Schneider] was investigated using a modified Murashige–Skoog as the basal medium (BM). Proliferation rate was significantly higher in explants grown on BM + 1 mM trehalose compared to that in the phytohormone control medium. In multiplication stage, shoot proliferation rate of 4.8 was achieved in BM with 4.44 μM BA and 1 mM trehalose. The rooting induction with 14.7 μM IBA had a significant effect on root regeneration; the highest rooting percentage (46.6%) was obtained with 7 days of induction. The incorporation of trehalose to the IBA-rhizogenesis media decreased basal callus but with trehalose alone, root development was scant. In vitro plants showed anatomical features typical for the acclimatization stage.  相似文献   

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Acetylcholinesterase (AChE) plays a key role in terminating neurotransmission at cholinergic synapses. AChE is also found in tissues devoid of cholinergic responses, indicating its potential function beyond neurotransmission. It has been suggested that AChE may participate in development, differentiation, and pathogenic processes such as Alzheimer's disease and tumorigenesis. We examined AChE expression in human lung fibroblast cell line (HLF) upon induction of apoptosis by UV or G418. AChE is induced in all apoptotic cells examined as determined by cytochemical staining, immunological analysis, affinity  相似文献   

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