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1.
Because of its neurocognitive enhancing effects, Gingko biloba has emerged as amongst the most commonly used herbal products. We report a liver transplant recipient with potentially life-threatening toxicity resulting from Gingko biloba use. Seven days after a second liver transplantation for recurrent hepatitisB virus infection, subphrenic hematoma was documented in a 59-year-old Korean patient. Failure to control bleeding with CT-guided drainage necessitated exploratory laparotomy for the evacuation of a large subphrenic hematoma. Three weeks later, an episode of vitreous hemorrhage was documented. Unbeknownst to his care providers, the patient had been consuming Gingko biloba throughout the postoperative period. No further bleeding episodes occurred after the cessation of Gingko biloba use. Unrecognized use of herbal products may be associated with serious side effects and adverse clinical sequelae in transplant recipients. Given their increasing popularity, the use of herbal products should be routinely sought as part of the history in transplant recipients. 相似文献
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The mitochondrial intron rI1 is a self-splicing group-II intron of algal mitochondria that can be transferred into chloroplasts
from the green alga Chlamydomonas reinhardtii for in vivo investigations (Herdenberger et al. 1994). Thus, rI1 is a suitable system to compare in vitro and in vivo RNA
processing. Interestingly, rI1 shows correct RNA splicing, although typical cis-acting exon-sequences (IBS2, δ) of group-II introns are lacking. In order to examine the effect of these exon-intron interactions on splicing, we introduced
the endogenous mitochondrial IBS2 sequence in order to produce optimal IBS2-EBS2 base pairing. In addition, the first nucleotide
of the 3′exon (δ′) was substituted to create an optimal δ-δ′ interaction. Neither of the two mutations, nor a combination of both, had any effect on the precision of the splice-site
selection. Unexpectedly, introduction of IBS2 led to a reduction in the efficiency of the second splicing step in vitro but
not in vivo. These findings lead us to conclude that trans-acting factors are present in vivo to optimize splicing efficiency. The possibility is discussed that these factors may,
for example, stabilize tertiary intron structures that are a prerequisite for correct RNA processing. Furthermore, our data
indicate that similar trans-acting factors promote correct intron splicing in chloroplasts and mitochondria.
Received: 18 October / 4 December 1997 相似文献
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M. Müller R. Heicappell F. Habermann M. Kaufmann U. Steiner K. Miller 《Urological research》1997,25(3):187-192
CD44 is the principal cell surface receptor for hyaluronate. Variant forms of the receptor, produced by alternative splicing, have been found to be associated with tumor progression in a variety of cancers. Based on investigations at the RNA level, it has recently been proposed that expression of CD44 variant V2 was present in urothelial cancer but not in normal urothelium. Since a distinctive marker for urothelial cancer would be extremely useful, frozen sections of normal urothelium and urothelial cancer were examined for expression of standard CD44 and CD44V2. Frozen sections of specimens of 35 patients with transitional cell carcinoma of the bladder, 16 specimens of normal bladder and 5 ureters were examined. Immunohistochemical staining was performed using a polyclonal antibody to CD44V2 (PAB CD44V2), a monoclonal antibody to CD44V2 (MAB CD44V2) and a monoclonal antibody to CD44S (MAB CD44S). CD44V2 and CD44S were also measured in lysates of urine sediments from 21 patients by enzyme-linked immunoabsorbent assay (ELISA). All investigated transitional cell carcinomas expressed CD44V2. There was no differentiation between invasive and noninvasive carcinoma. CD44V2 was also expressed in normal urothelium. Standard CD44 was expressed by the transitional cell carcinoma, normal urothelium, musculature and interstitial tissue. The amount of CD44V2 and CD44S in lysates of urine sediments is not correlated to diagnosis. In contrast to investigations at the RNA level, CD44V2 on the protein level seems not to be a distinctive marker for urothelial cancer. Therefore, CD44V2 will not be a useful diagnostic marker for detection of transitional cell carcinoma. 相似文献
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Objective To characterize a possible retention function of unique sequence in the 5'end of rat testis GABAA receptor β3t splicing variantMethods Rat testis GABAA receptor β3t splicing variant cDNA was cloned and two eukaryotic expression recombinant plasmids of pEGFP-N1 and pEGFP-C1 were constructed respectively by fusing green fluorescent protein to the N or C-terminus of β3t isoform. The recombinant plasmids were transfected into CHO cells by calcium phosphate co-precipitation method. Fluorescence microscope and laser confocal microscope were used to analyze localization of β3t in the transfected cells. ConA-Texas-Red was used to label cell ER and the localization of rat testis β3t splicing variant in CHO cells was determined.Results When rat testis β3t splicing variant was expressed in CHO cells, two expression patterns were delineated, the distributions of uniform and mainly discrete intracellular compartments respectively. The chimera product failed to be translocated into the cell surface when expressed in CHO cells; whereas the β3 subunit of rat brain was incorporated into the plasma membrane.Conclusion The inability of β3t to target into the ER may be a consequence of the unique 25 specific amino acid segments in the N terminus. 相似文献
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Ast Gil; Goldblatt Drora; Waisman Ari; Sperling Ruth; Mozes Edna; Sperling Joseph 《International immunology》1994,6(8):1097-1105
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Biochemical analysis of plasma-soluble invariant chains and their complex formation with soluble HLA-DR 总被引:1,自引:0,他引:1
The invariant chain (CD74) is preferentially localized in the cytoplasm and regulates the loading of exogenous derived peptides into HLA class II heterodimers. In addition, a small proportion of CD74:class II complexes is also expressed on the cell surface. We identified and quantified soluble CD74 (sCD74) molecules in the plasma and sCD74:sHLA-DR complexes by ELISA. EDTA plasma samples from 86 healthy probands were analyzed. sCD74 could be detected in all samples with a mean concentration of 1.14 relative units±1.04 SD (range 0.17-4.31). Approximately 10% of the samples had increased amounts of sCD74 (3.0 relative units). Complexes of sCD74 and sHLA-DR were detected in all samples and their quantities were positively correlated (r=0.83, p0.001) with the sCD74 concentrations. SDS-PAGE analysis of plasma samples with high sCD74 concentrations (3.0 relative units) revealed four isoforms of sCD74 with molecular weights of 45, 43, 35, 31 kDa corresponding to known sizes of intracellular CD74. However, only molecular weights of the 45 and 43 kDa isoforms of sCD74 are found complexed with sHLA-DR. Our data demonstrate, that CD74 molecules are present in their soluble form in the plasma of healthy probands and form complexes with soluble HLA-DR molecules. 相似文献