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141.
142.
Burkart V Germaschewski L Schloot NC Bellmann K Kolb H 《Biochemical and biophysical research communications》2008,369(2):421-425
Type 1 diabetes is caused by the immune-mediated destruction of pancreatic beta cells. Animal models of the disease demonstrate an increased susceptibility of beta cells to immunological attacks due to their defective stress-responsiveness. To investigate the stress-responsiveness in human type 1 diabetes we analyzed the heat-inducibility of the dominant stress protein heat shock protein (Hsp)70 in diabetic patients at different disease stages. At diabetes-manifestation heat-induced Hsp70 levels in peripheral blood mononuclear cells (PBMC) reached only about 25% of the levels expressed by heat-treated PBMC from non-diabetic subjects (p < 0.05). Heat-responsiveness improved with disease duration and was re-established at more than eight months after disease-manifestation. Hyperthermia-induced Hsp70 expression was decreased by the T-helper 1-associated cytokine interferon-γ and increased by the T-helper 2-associated transforming growth factor-β. We conclude that impaired cellular stress-responsiveness, aggravated by the inflammatory milieu at the onset of type 1 diabetes, contributes to disease manifestation. 相似文献
143.
Rosanna Wijenberg Stephen Takács Melissa Cook Gerhard Gries 《Entomologia Experimentalis et Applicata》2008,129(2):124-131
Insects deciding whether to approach and join a group of conspecifics may utilize olfactory and auditory signals, or cues, from that group as indicators of its size or the suitability of its shelter. Here we show (1) that German cockroaches, Blattella germanica L. (Dictyoptera: Blattellidae), in groups wing‐fan; (2) that the incidence of wing‐fanning (WF) increases proportionately to group size; and (3) that gravid females utilize auditory cues associated with WF behaviour when they decide whether or not to enter a shelter. In binary choice arena bioassays, proportionately more gravid females avoided shelters associated with play‐back of high‐incidence male‐ or female‐produced WF sound, indicating a high‐density group of conspecifics, but sought shelters associated with play‐back of low‐incidence WF sound, indicating a low‐density group of conspecifics. These auditory cues seem to convey information on group size or density, avoid sensory fatigue in enclosed environments, and allow sonotactic orientation to the group's location. 相似文献
144.
Frank J. Dekker Massimo Ghizzoni Nanette van der Meer Rosalina Wisastra Hidde J. Haisma 《Bioorganic & medicinal chemistry》2009,17(2):460-466
Small molecule HAT inhibitors are useful tools to unravel the role of histone acetyl transferases (HATs) in the cell and have relevance for oncology. We present a systematic investigation of the inhibition of the HAT p300/CBP Associated Factor (PCAF) by isothiazolones with different substitutions. 5-chloroisothiazolones proved to be the most potent inhibitors of PCAF. The growth inhibition of 4 different cell lines was studied and the growth of two cell lines (A2780 and HEK 293) was inhibited at micromolar concentrations by 5-chloroisothiazolones. Furthermore, the 5-chloroisothiazolone preservative Kathon? CG that is used in cosmetics inhibited PCAF and the growth of cell lines A2780 and HEK 293, which indicates that this preservative should be applied with care. 相似文献
145.
Su Wang Bruce Ziman Ilona Bodi Marta Rubio Ying-Ying Zhou Karen D'Souza Nanette H. Bishopric Arnold Schwartz Edward G. Lakatta 《PloS one》2009,4(1)
Mice over-expressing the α1−subunit (pore) of the L-type Ca2+ channel (α1CTG) by 4months (mo) of age exhibit an enlarged heart, hypertrophied myocytes, increased Ca2+ current and Ca2+ transient amplitude, but a normal SR Ca2+ load. With advancing age (8–11 mo), some mice demonstrate advanced hypertrophy but are not in congestive heart failure (NFTG), while others evolve to frank dilated congestive heart failure (FTG). We demonstrate that older NFTG myocytes exhibit a hypercontractile state over a wide range of stimulation frequencies, but maintain a normal SR Ca2+ load compared to age matched non-transgenic (NTG) myocytes. However, at high stimulation rates (2–4 Hz) signs of diastolic contractile failure appear in NFTG cells. The evolution of frank congestive failure in FTG is accompanied by a further increase in heart mass and myocyte size, and phospholamban and ryanodine receptor protein levels and phosphorylation become reduced. In FTG, the SR Ca2+ load increases and Ca2+ release following excitation, increases further. An enhanced NCX function in FTG, as reflected by an accelerated relaxation of the caffeine-induced Ca2+ transient, is insufficient to maintain a normal diastolic Ca2+ during high rates of stimulation. Although a high SR Ca2+ release following excitation is maintained, the hypercontractile state is not maintained at high rates of stimulation, and signs of both systolic and diastolic contractile failure appear. Thus, the dilated cardiomyopathy that evolves in this mouse model exhibits signs of both systolic and diastolic failure, but not a deficient SR Ca2+ loading or release, as occurs in some other cardiomyopathic models. 相似文献
146.
Zooplankton in the Schelde estuary, Belgium and The Netherlands. Spatial and temporal patterns 总被引:9,自引:0,他引:9
Tackx Micky L. M.; de Pauw Nathalie; van Mieghem Riet; Azemar F.; Hannouti Abdelhacq; van Damme Stefan; Fiers Frank; Daro Nanette; Meire Patrick 《Journal of plankton research》2004,26(2):133-141
The zooplankton fauna of the Zeeschelde estuary (Belgium) wasinvestigated over 10 months by means of monthly sampling. CanonicalCorrespondence Analysis (CCA) was used to relate the speciesdistribution to environmental factors. The variation in thespecies data was significantly (P < 0.05) related to a setof 10 environmental variables (chlorinity, NH4+, temperature,PO4-P-, DW, Chl a and Chl b, NO2-N, NO3-N and pH). The mainspatial and seasonal gradients were associated with chlorinityand temperature respectively. The brackish water zone was dominatedby the calanoid Eurytemora affinis in spring, succeeded by Acartiatonsa and mysid species during summer. In the freshwater transect,cyclopoids dominated, together with several cladoceran species.Thermophilic cyclopoid species (Thermocyclops oithonoides, Th.crassus and Mesocyclops leuckarti) occurred during periods ofmaximal temperature. The cyclopoids Acanthocyclops robustus,Paracyclops poppei and Cyclops vicinus, the cladocerans Daphnialongispina, Chydorus sphaericus and Bosmina longirostris togetherwith the numerically dominant rotifers, oligochaetes, nematodesand juvenile copepods seemed little affected by environmentalgradients. 相似文献
147.
Distinct RIG-I and MDA5 signaling by RNA viruses in innate immunity 总被引:11,自引:2,他引:9
Loo YM Fornek J Crochet N Bajwa G Perwitasari O Martinez-Sobrido L Akira S Gill MA García-Sastre A Katze MG Gale M 《Journal of virology》2008,82(1):335-345
Alpha/beta interferon immune defenses are essential for resistance to viruses and can be triggered through the actions of the cytoplasmic helicases retinoic acid-inducible gene I (RIG-I) and melanoma differentiation-associated gene 5 (MDA5). Signaling by each is initiated by the recognition of viral products such as RNA and occurs through downstream interaction with the IPS-1 adaptor protein. We directly compared the innate immune signaling requirements of representative viruses of the Flaviviridae, Orthomyxoviridae, Paramyxoviridae, and Reoviridae for RIG-I, MDA5, and interferon promoter-stimulating factor 1 (IPS-1). In cultured fibroblasts, IPS-1 was essential for innate immune signaling of downstream interferon regulatory factor 3 activation and interferon-stimulated gene expression, but the requirements for RIG-I and MDA5 were variable. Each was individually dispensable for signaling triggered by reovirus and dengue virus, whereas RIG-I was essential for signaling by influenza A virus, influenza B virus, and human respiratory syncytial virus. Functional genomics analyses identified cellular genes triggered during influenza A virus infection whose expression was strictly dependent on RIG-I and which are involved in processes of innate or adaptive immunity, apoptosis, cytokine signaling, and inflammation associated with the host response to contemporary and pandemic strains of influenza virus. These results define IPS-1-dependent signaling as an essential feature of host immunity to RNA virus infection. Our observations further demonstrate differential and redundant roles for RIG-I and MDA5 in pathogen recognition and innate immune signaling that may reflect unique and shared biologic properties of RNA viruses whose differential triggering and control of gene expression may impact pathogenesis and infection. 相似文献
148.
The formation of chimeric colonies following allogeneic contact between benthic invertebrates may strongly affect colony fitness. Here we show that, in a field population of the colonial ascidian Botryllus schlosseri in Monterey Bay, California, more than 20% of all colonies occur in allogeneic contact with conspecifics. We experimentally assessed the effects of allogeneic contact on the following life-history traits under natural field conditions: growth, age and size at first reproduction, and egg production (fecundity). When compared with isolated colonies, and in some cohorts also with colonies that rejected allogeneic neighbors, colonies that fused with neighbors incurred reduced fitness in terms of most life-history traits measured. We propose that one of the benefits of precise allorecognition is that, in fused colonies, it limits the unit of selection to chimeric individuals composed of closely related kin. 相似文献
149.
Aryal Sitaram Nielsen Uffe N. Sumaya Nanette H. De Faveri Stefano Wilson Craig Riegler Markus 《BioControl》2022,67(1):63-74
BioControl - Entomopathogenic nematodes (EPNs) are used in biological control of pest insects but their potential may be limited by strain availability from different bioregions and effectiveness... 相似文献
150.
Antarctic lakes are extreme ecosystems with microbially dominated food webs, in which viruses may be important in controlling
community dynamics. A year long investigation of two Antarctic saline lakes (Ace and Pendant Lakes) revealed high concentrations
of virus like particles (VLP) (0.20–1.26 × 108 ml−1), high VLP: bacteria ratios (maximum 70.6) and a seasonal pattern of lysogeny differing from that seen at lower latitudes.
Highest rates of lysogeny (up to 32% in Pendant Lake and 71% in Ace Lake) occurred in winter and spring, with low or no lysogeny
in summer. Rates of virus production (range 0.176–0.823 × 106 viruses ml−1 h−1) were comparable to lower latitude freshwater lakes. In Ace Lake VLP did not correlate with bacterial cell concentration
or bacterial production but correlated positively with primary production, while in Pendant Lake VLP abundance correlated
positively with both bacterial cell numbers and bacterial production but not with primary production. In terms of virus and
bacterial dynamics the two saline Antarctic lakes studied appear distinct from other aquatic ecosystems investigated so far,
in having very high viral to bacterial ratios (VBR) and a very high occurrence of lysogeny in winter. 相似文献