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371.
Human cytomegalovirus-induced immediate early antigens: analysis in sodium dodecyl sulfate-polyacrylamide gel electrophoresis after immunoprecipitation.
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Immediate early antigen (IEA) induced in human lung fibroblasts by human cytomegalovirus was characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis after immunoprecipitation with IEA-positive human sera. Two polypeptides of 76,000 daltons (76K) and 82K were detectable within 90 min after infection. Polypeptides of similar molecular weight were also found in immunoprecipitates of human cytomegalovirus-infected cells nonpermissive for virus replication. IEA is located within the nucleus, although some of the 76K material appears to be located on the outer nuclear membrane. Raising salt concentrations in the extraction buffer increased antigen extraction. The contribution of these IEA polypeptides to IEA nuclear fluorescent staining is discussed. 相似文献
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Infection by human varicella-zoster virus confers norepinephrine sensitivity to sensory neurons from rat dorsal root ganglia. 总被引:2,自引:0,他引:2
Varicella-zoster virus (VZV) is a widespread human herpes virus causing chicken pox on primary infection and persisting in sensory neurons. Reactivation causes shingles, which are characterized by severe pain and often lead to postherpetic neuralgia. To elucidate the mechanisms of VZV-associated hyperalgesia, we elaborated an in vitro model for the VZV infection of sensory neurons from rat dorsal root ganglia. Between 35 and 50% of the neurons showed strong expression of the immediate-early virus antigens IE62 and IE63 and the late glycoprotein gE. When the intracellular calcium concentration was monitored microfluorometrically for individual cells after infection, the sensitivity to GABA or capsaicin was similar in controls and in VZV-infected neurons. However, the baseline calcium concentration was increased. Neurons became de novo sensitive to adrenergic stimulation after VZV infection. Norepinephrine-responsive neurons were more frequent and calcium responses to norepinephrine were significantly higher after infection with wild-type isolates than with the attenuated vaccine strain OKA. The adrenergic agonists phenylephrine and isoproterenol had similar efficacy. We suggest that the infection with wild-type VZV isolates confers norepinephrine sensitivity to sensory neurons by using alpha(1)- and/or beta(1)-adrenergic receptors providing a model for the pathophysiology of the severe pain associated with the acute reactivation of VZV. 相似文献
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M. Wing Goodale David C. Evers Steven E. Mierzykowski Alexander L. Bond Neil M. Burgess Catherine I. Otorowski Linda J. Welch C. Scott Hall Julie C. Ellis R. Bradford Allen Anthony W. Diamond Stephen W. Kress Robert J. Taylor 《EcoHealth》2008,5(4):409-425
From existing databases, we compiled and evaluated 604 total mercury (Hg) levels in the eggs and blood of 17 species of marine
foraging birds from 35 Gulf of Maine islands to provide baseline data and to determine the best tissue, age class, and species
for future biomonitoring. While mean Hg levels in most species did not exceed adverse effects thresholds, levels in some individual
eggs did; for all species arithmetic mean egg Hg levels ranged from 0.04 to 0.62 (μg/g, wet weight). Piscivorous birds had
higher Hg levels than invertivores. Leach’s storm-petrel (Oceanodroma leucorhoa), razorbill (Alca torda), and black guillemot (Cepphus grylle) adult blood and egg Hg levels were higher than other species. Our results indicate that adult blood is preferable to chick
blood for detecting long-term temporal trends because adult levels are higher and not confounded by metabolic effects. However,
since we found that eggs and adult blood are comparable indicators of methylmercury bioavailability, we determined that eggs
are the preferred tissue for long-term Hg monitoring because the relative ease in collecting eggs ensures consistent and robust
datasets. We suggest specific sampling methods, and based on our results demonstrate that common eider (Somateria mollissima), Leach’s storm-petrel, double-crested cormorant, and black guillemot are the most effective bioindicators of Hg of the Gulf
of Maine. 相似文献
378.
Mand S Marfo-Debrekyei Y Debrah A Buettner M Batsa L Pfarr K Adjei O Hoerauf A 《Filaria journal》2005,4(1):1-11
BACKGROUND: Ultrasonography (USG) is known to be a suitable tool for diagnosis in lymphatic filariasis as the adult filarial nematode Wuchereria bancrofti in scrotal lymphatic vessels of infected men can be detected by the characteristic pattern of movement, the Filaria Dance Sign. In onchocerciasis, moving adult worms have not yet been demonstrated by USG. In addition the verification of drug effects on living adult Onchocerca volvulus filariae in trials is hampered by the lack of tools for longitudinal observation of alterations induced by potentially macrofilaricidal drugs in vivo. The present study was carried out to determine the frequency of detection of moving adult filariae of O. volvulus by USG. METHODS: In an endemic region for onchocerciasis in Ghana, 61 patients infected with onchocerciasis were recruited by palpation and onchocercomas examined by USG using an ultrasound system equipped with a 7.5 - 10 MHz linear transducer. Onchocercomas were recorded on videotape and evaluated with regard to location, number and size, as well as to movements of adult filariae. RESULTS: In the 61 patients 303 onchocercomas were found by palpation and 401 onchocercomas were detected by USG. In 18 out of 61 patients (29.5%), altogether 22 nodules with moving adult O. volvulus filariae were detected and are presented in animated ultrasound images as mp-4 videos. CONCLUSION: Ultrasonographical examinations of onchocercomas where living adult filariae can be displayed may serve as a new tool for the longitudinal observation in vivo of patients with onchocerciasis undergoing treatment and as an adjunct to histological evaluation. 相似文献
379.
Aspergillus nidulans uvsBATR and scaANBS1 genes show genetic interactions during recovery from replication stress and DNA damage
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Fagundes MR Semighini CP Malavazi I Savoldi M de Lima JF de Souza Goldman MH Harris SD Goldman GH 《Eukaryotic cell》2005,4(7):1239-1252
The ATM/ATR kinases and the Mre11 (Mre11-Rad50-Nbs1) protein complex are central players in the cellular DNA damage response. Here we characterize possible interactions between Aspergillus nidulans uvsB(ATR) and the Mre11 complex (scaA(NBS1)). We demonstrate that there is an epistatic relationship between uvsB(ATR), the homolog of the ATR/MEC1 gene, and scaA(NBS1), the homolog of the NBS1/XRS2 gene, for both repair and checkpoint functions and that correct ScaA(NBS1) expression during recovery from replication stress depends on uvsB(ATR). In addition, we also show that the formation of UvsC foci during recovery from replication stress is dependent on both uvsB(ATR) and scaA(NBS1) function. Furthermore, ScaA(NBS1) is also dependent on uvsB(ATR) for nuclear focus formation upon the induction of DNA double-strand breaks by phleomycin. Our results highlight the extensive genetic interactions between UvsB and the Mre11 complex that are required for S-phase progression and recovery from DNA damage. 相似文献
380.
In Drosophila melanogaster, the apparently unrelated genes anon-66Da, RpL14, and anon-66Db (from telomere to centromere) are located on a 5547 bp genomic fragment on chromosome arm 3L at cytological position 66D8. The three genes are tightly linked, and flanked by two relatively large genes with unknown function. We have taken a comparative genomic approach to investigate the evolutionary history of the three genes. To this end we isolated a Drosophila virilis 7.3 kb genomic fragment which is homologous to a 5.5 kb genomic region of D. melanogaster. Both fragments map to Muller's element D, namely to section 66D in D. melanogaster and to section 32E in D. virilis, and harbor the genes anon-66Da, RpL14, and anon-66Db. We demonstrate that the three genes exhibit a high conservation of gene topography in general and in detail. While most introns and intergenic regions reveal sequence divergences, there are, however, a number of interspersed conserved sequence motifs. In particular, two introns of the RpL14 gene contain a short, highly conserved 60 nt long sequence located at corresponding positions. This sequence represents a novel Drosophila small nucleolar RNA, which is homologous to human U49. Whereas DNA flanking the three genes shows no significant interspecies homologies, the 3'-flanking region in D. virilis contains sequences from the transposable element Penelope. The Penelope family of transposable elements has been shown to promote chromosomal rearrangements in the D. virilis species group. The presence of Penelope sequences in the D. virilis 7.3 kb genomic fragment may be indicative for a transposon-induced event of transposition which did not yet scramble the order of the three genes but led to the breakdown of sequence identity of the flanking DNA. 相似文献