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11.
Molecular and biological analysis of echovirus 9 strain isolated from a diabetic child 总被引:2,自引:0,他引:2
Paananen A Ylipaasto P Rieder E Hovi T Galama J Roivainen M 《Journal of medical virology》2003,69(4):529-537
The full-length infectious cDNA clone was constructed and sequenced from the strain DM of echovirus 9, which was recently isolated from a 6-week-old child at the clinical onset of type 1 diabetes. Parallel with the isolate DM, the full-length infectious cDNA clone of the prototype strain echovirus 9 Barty (Barty-INF), was constructed and sequenced. Genetic relationships of the sequenced echo 9 viruses to the other members of the human enterovirus type B species were studied by phylogenetic analyses. Comparison of capsid protein sequences showed that the isolate DM was closely related to both prototype strains: Hill and Barty-INF. The only exception was the inner capsid protein VP4 where serotype specificity was not evident and the isolate DM clustered with the strain Hill and the strain Barty-INF with echovirus 30 Bastianni. Likewise, the nonstructural protein coding region, P2P3, of isolate DM was more similar to strain Hill than to strain Barty-INF. However, like echovirus 9 Barty, the isolate DM contained the RGD-motif in the carboxy terminus of capsid protein VP1. By blocking experiments using an RGD-containing peptide and a polyclonal rabbit antiserum to the alpha(v)beta(3)-integrin, it was shown that this molecule works as a cellular receptor for isolate DM. By using primary human islets, it was shown that the isolate DM is capable of infecting insulin-producing beta-cells like the corresponding prototype strains did. However, only isolate DM was clearly cytolytic for beta-cells. The infectious clones that were made allow further investigations of the molecular features responsible for the diabetogenicity of the isolate DM. 相似文献
12.
Role of the galactose lectin of Entamoeba histolytica in adherence-dependent killing of mammalian cells. 总被引:1,自引:2,他引:1
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Entamoeba histolytica extracellular killing of host cells is contact dependent. Adherence to human colonic epithelial cells and mucins is mediated by a galactose-specific lectin. The effect on cytotoxicity of a panel of monoclonal antibodies (MAb) directed against the galactose lectin was tested. As expected, those MAb which inhibited adherence also decreased cytotoxicity. However, one antilectin MAb blocked cytotoxicity after adherence had occurred, indicating that the lectin has a role in cell killing that is distinct from its adherence function. 相似文献
13.
Harimaya A Tarkkanen J Mattila P Fujii N Ylikoski J Himi T 《Clinical and diagnostic laboratory immunology》2005,12(9):1130-1134
We evaluated the immunological potential of adenoidal lymphocytes from children with recurrent otitis media. Interleukin-4 release and CD69 expression were lower in adenoidal lymphocytes than in peripheral blood lymphocytes (PBL). Our results suggest that there may be a difference between the immunological potential of adenoidal lymphocytes and that of PBL in children with otitis. 相似文献
14.
Analysis of the floral transcriptome uncovers new regulators of organ determination and gene families related to flower organ differentiation in Gerbera hybrida (Asteraceae)
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Laitinen RA Immanen J Auvinen P Rudd S Alatalo E Paulin L Ainasoja M Kotilainen M Koskela S Teeri TH Elomaa P 《Genome research》2005,15(4):475-486
Development of composite inflorescences in the plant family Asteraceae has features that cannot be studied in the traditional model plants for flower development. In Gerbera hybrida, inflorescences are composed of morphologically different types of flowers tightly packed into a flower head (capitulum). Individual floral organs such as pappus bristles (sepals) are developmentally specialized, stamens are aborted in marginal flowers, petals and anthers are fused structures, and ovaries are located inferior to other floral organs. These specific features have made gerbera a rewarding target of comparative studies. Here we report the analysis of a gerbera EST database containing 16,994 cDNA sequences. Comparison of the sequences with all plant peptide sequences revealed 1656 unique sequences for gerbera not identified elsewhere within the plant kingdom. Based on the EST database, we constructed a cDNA microarray containing 9000 probes and have utilized it in identification of flower-specific genes and abundantly expressed marker genes for flower scape, pappus, stamen, and petal development. Our analysis revealed several regulatory genes with putative functions in flower-organ development. We were also able to associate a number of abundantly and specifically expressed genes with flower-organ differentiation. Gerbera is an outcrossing species, for which genetic approaches to gene discovery are not readily amenable. However, reverse genetics with the help of gene transfer has been very informative. We demonstrate here the usability of the gerbera microarray as a reliable new tool for identifying novel genes related to specific biological questions and for large-scale gene expression analysis. 相似文献
15.
The Effect of Small Variation of the Frequent Auditory Stimulus on the Event-Related Brain Potential to the Infrequent Stimulus 总被引:1,自引:0,他引:1
Istvan Winkler. Petri Paavilainen Kimmo Alho Kalevi Reinikainen Mikko Sams Risto Naatanen 《Psychophysiology》1990,27(2):228-235
We investigated whether the mismatch process between a rare stimulus and the trace of frequent stimulus, which generates the mismatch-negativity component of the event-related potential, can tolerate a small variation in the intensity of the frequent stimulus. Series of short tone pips were presented to 10 subjects while they were reading a book and ignoring the auditory stimuli. The intensity (mean 80dB) of the frequent stimulus (600 Hz) varied within a range that was different in different blocks. The probability of the infrequent stimuli which were, in different blocks, either intensity deviants (600 Hz/70dB) or frequency deviants (650 Hz/80dB) was 10%. Both deviant stimuli elicited mismatch negativity even when the intensity of the frequent stimulus varied, although the amplitude of this component decreased with the increasing variability of the frequent stimulus. These results show that the generator process of mismatch negativity tolerates some variation in the repetitive stimulus, thus indicating that this process is also activated in ecologically more valid conditions. This is crucial to the interpretation of the generator process of mismatch negativity as a biologically vital warning mechanism. 相似文献
16.
17.
PURPOSE: The inactive form of pyruvatekinase could be established in different tumours. Purpose of this study was to demonstrate the presence or absence of the inactive form of pyruvatekinase in renal cell carcinoma, metastases and benign renal tissue by immunohistology. METHOD: After deparaffinization of formaline-fixed tissue (5 original tumours, 2 metastases and 5 benign renal tissues) cells were stained (APAAP-method) with Clon DF4 (ScheBo Tech). RESULTS: All malign tissue showed a positive reaction, inside benign tissue we saw a positive reaction of endothelial cells however we saw no reaction with benign renal cells. CONCLUSION: Renal cell carcinoma and metastatic cells show a strong immunohistological reaction against the inactive form of pyruvatekinase, no reaction of benign renal cells. It should be possible to develop a serological tumour marker for renal cell carcinoma. 相似文献
18.
Nikola Bradarić Volga Punda-Polić lvo Milas Ivo Ivić Dušanka Grgić Nikola Radošević lvo Petrić 《European journal of epidemiology》1996,12(4):409-412
Two outbreaks of typhoid fever caused by Salmonella typhi of the same phagotype (A, biotype II) and antibiotic susceptibility are reported. Both occurred during the war in Bosnia and Herzegovina. The first outbreak appeared among the refugees from the town of Jajce. The second outbreak appeared among the inhabitants in the village of Vidosi near Livno. This report describes main clinical, epidemioloigcal and laboratory findings for 22 patients treated in Split University Hospital, Croatia, in the period November 1992–January 1993. Possible epidemiological connections between those two outbreaks are discussed. 相似文献
19.
Absorption/metabolism of sulforaphane and quercetin, and regulation of phase II enzymes, in human jejunum in vivo. 总被引:2,自引:0,他引:2
Niclas Petri Christer Tannergren Birgit Holst Fred A Mellon Yongping Bao Geoff W Plumb Jim Bacon Karen A O'Leary Paul A Kroon Lars Knutson Patrik Forsell Thomas Eriksson Hans Lennernas Gary Williamson 《Drug metabolism and disposition》2003,31(6):805-813
For the first time the human intestinal effective permeability, estimated from the luminal disappearance and intestinal metabolism of phytochemicals, sulforaphane and quercetin-3,4'-glucoside, as well as the simultaneous changes in gene expression in vivo in enterocytes, has been studied in the human jejunum in vivo (Loc-I-Gut). Both compounds as components of an onion and broccoli extract could readily permeate the enterocytes in the perfused jejunal segment. At the physiologically relevant, dietary concentration tested, the average effective jejunal permeability (Peff) and percentage absorbed (+/- S.D.) were 18.7 +/- 12.6 x 10-4 cm/s and 74 +/- 29% for sulforaphane and 8.9 +/- 7.1 x 10-4 cm/s and 60 +/- 31% for quercetin-3,4'-diglucoside, respectively. Furthermore, a proportion of each compound was conjugated and excreted back into the lumen as sulforaphane-glutathione and quercetin-3'-glucuronide. The capacity of the isolated segment to deconjugate quercetin from quercetin-3,4'-diglucoside during the perfusion was much higher than the beta-glucosidase activity of the preperfusion jejunal contents, indicating that the majority (79-100%) of the beta-glucosidase capacity derives from the enterocytes in situ. Simultaneously, we determined short-term changes in gene expression in exfoliated enterocytes, which showed 2.0 +/- 0.4-fold induction of glutathione transferase A1 (GSTA1) mRNA (p < 0.002) and 2.4 +/- 1.2-fold induction of UDP-glucuronosyl transferase 1A1 (UGT1A1) mRNA (p < 0.02). The changes in gene expression were also seen in differentiated Caco-2 cells, where sulforaphane was responsible for induction of GSTA1 and quercetin for induction of UGT1A1. These results show that food components have the potential to modify drug metabolism in the human enterocyte in vivo very rapidly. 相似文献
20.
Versluis RG Petri H Vismans FJ van de Ven CM Springer MP Papapoulos SE 《Calcified tissue international》2000,66(1):1-4
Radiographic absorptiometry (RA) of the phalanges is a convenient and reliable technique for measuring bone mineral density
(BMD). It needs only a radiograph of the hand, which can be sent for evaluation to a central facility, whereas other techniques
require specialized equipment. We assessed the relationship between RA measurements and the presence of vertebral deformities
in a population-based cohort of postmenopausal women, and to compare the results with simultaneously obtained BMD of the hip
by dual-energy X-ray absorptiometry (DXA). A total of 389 women aged 55–84 (mean age 67.2 years, SD 8.7) were randomly selected
from a large general practice. RA, DXA of the hip, and vertebral deformities in the lateral spine X-rays by vertebral morphometry
were assessed. Thirty-eight women (9.8%) had severe (grade II) vertebral deformities, and their BMD at the phalanges and femoral
neck was significantly lower than that of women without severe vertebral deformities. Odds ratios for the presence of severe
vertebral deformities of 1.5 (95% CI: 1.1–2.1) for RA and 1.3 (95% CI: 0.9–1.9) for DXA, together with similar receiver operating
characteristics curves, were found using age-adjusted logistic regression. Phalangeal BMD is related to vertebral deformities
at least as closely as BMD of the femoral neck BMD. RA may therefore help to evaluate fracture risk, especially if no DXA
equipment is available.
Received: 21 July 1998 / Accepted: 1 July 1999 相似文献