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71.
Comparison of the ECST, CC, and NASCET grading methods and ultrasound for assessing carotid stenosis
Staikov IN Arnold M Mattle HP Remonda L Sturzenegger M Baumgartner RW Schroth G 《Journal of neurology》2000,247(9):681-686
We compared three angiographic methods for grading of carotid stenosis and examined the correlation between angiographic
and ultrasound findings. Two observers independently measured 111 carotid stenoses on arteriographic films of 84 patients.
The stenoses were graded according to the European Carotid Surgery Trial (ECST), North American Symptomatic Carotid Endarterectomy
Trial (NASCET), and Common Carotid (CC) methods. The results obtained by these methods were compared, and the interobserver
reproducibility of the measurements was calculated. In addition, all angiographic results were compared to ultrasound findings
obtained before angiography. Measurements using the CC method were the most reproducible and those using the NASCET method
the least. The NASCET method underestimated the degree of stenosis compared to the other methods. The ECST and CC methods
yielded almost identical results (97% agreement). Ultrasound provided an accuracy of 94% compared to ECST and CC methods and
84% compared to the NASCET method. Interobserver reproducibility of angiographic quantification of carotid stenoses was best
for the CC and ECST methods and least for the NASCET method. Ultrasound demonstrated better accuracy than the ECST and CC
methods.
Received: 7 April 1999/Received in revised form: 5 October 1999/Accepted: 11 April 2000 相似文献
72.
Grant A McArthur George D Demetri Allan van Oosterom Michael C Heinrich Maria Debiec-Rychter Christopher L Corless Zariana Nikolova Sasa Dimitrijevic Jonathan A Fletcher 《Journal of clinical oncology》2005,23(4):866-873
PURPOSE: The cutaneous malignant tumor dermatofibrosarcoma protuberans (DFSP) is typically associated with a translocation between chromosomes 17 and 22 that places the platelet-derived growth factor-B (PDGFB) under the control of the collagen 1A1 promoter. The purpose of this study was to evaluate molecular, cytogenetic, and kinase activation profiles in a series of DFSPs and to determine whether these biologic parameters are correlated with the clinical responses of DFSP to imatinib. PATIENTS AND METHODS: We analyzed the objective radiologic and clinical response to imatinib at 400 mg twice daily in eight patients with locally advanced DFSP and two patients with metastatic disease. RESULTS: Each of eight patients with locally advanced DFSP had evidence of t(17;22) and showed a clinical response to imatinib. Four of these patients had complete clinical responses. The two patients with metastatic disease had fibrosarcomatous histology and karyotypes that were substantially more complex than those typically associated with localized DFSP. One patient with metastatic DFSP and an associated t(17;22) had a partial response to imatinib but experienced disease progression after 7 months of therapy. In contrast, the other patient with metastatic disease had a tumor lacking t(17;22), and there was no clinical response to imatinib. Unexpectedly, there was minimal platelet-derived growth factor receptor-beta phosphorylation in the untreated DFSP, despite the documented presence of a PDGFB autocrine mechanism. CONCLUSION: Imatinib has clinical activity against both localized and metastatic DFSP with t(17;22). However, fibrosarcomatous variants of DFSP lacking t(17;22) may not respond to imatinib. 相似文献
73.
Familial gastrointestinal stromal tumor syndrome: phenotypic and molecular features in a kindred. 总被引:5,自引:0,他引:5
Frederick P Li Jonathan A Fletcher Michael C Heinrich Judy E Garber Stephen E Sallan Clara Curiel-Lewandrowski Anette Duensing Matt van de Rijn Lowell E Schnipper George D Demetri 《Journal of clinical oncology》2005,23(12):2735-2743
PURPOSE: Members of a family with hereditary gastrointestinal stromal tumors (GISTs) and a germline KIT oncogene mutation were evaluated for other potential syndrome manifestations. A tumor from the proband was analyzed to compare features with sporadic GISTs. PATIENTS AND METHODS: Members of a kindred in which six relatives in four consecutive generations comprised an autosomal dominant pattern of documented GISTs and cutaneous lesions underwent physical examination, imaging studies, and germline KIT analysis. A recurrent GIST from the proband was studied using microarray, karyotypic, immunohistochemical, and immunoblotting techniques. RESULTS: In addition to evidence of multiple GISTs, lentigines, malignant melanoma, and an angioleiomyoma were identified in relatives. A previously reported gain-of-function missense mutation in KIT exon 11 (T --> C) that results in a V559A substitution within the juxtamembrane domain was identified in three family members. The proband's recurrent gastric GIST had a 44,XY-14,-22 karyotype and immunohistochemical evidence of strong diffuse cytoplasmic KIT expression without expression of actin, desmin, or S-100. Immunoblotting showed strong expression of phosphorylated KIT and downstream signaling intermediates (AKT and MAPK) at levels comparable with those reported in sporadic GISTs. cDNA array profiling demonstrated clustering with sporadic GISTs, and expression of GIST markers comparable to sporadic GISTs. CONCLUSION: These studies provide the first evidence that gene expression and mechanisms of cytogenetic progression and cell signaling are indistinguishable in familial and sporadic GISTs. Current investigations of molecularly targeted therapies in GIST patients provide opportunities to increase the understanding of features of the hereditary syndrome, and risk factors and molecular pathways of the neoplastic phenotypes. 相似文献
74.
PDGFRA mutations in gastrointestinal stromal tumors: frequency, spectrum and in vitro sensitivity to imatinib. 总被引:30,自引:0,他引:30
Christopher L Corless Arin Schroeder Diana Griffith Ajia Town Laura McGreevey Patina Harrell Sharon Shiraga Troy Bainbridge Jason Morich Michael C Heinrich 《Journal of clinical oncology》2005,23(23):5357-5364
PURPOSE: Gastrointestinal stromal tumors (GISTs) commonly harbor oncogenic mutations of the KIT tyrosine kinase, which is a target for the kinase inhibitor imatinib. A subset of GISTs, however, contains mutations in the homologous kinase platelet derived growth factor receptor alpha (PDGFRA), and the most common of these mutations is resistant to imatinib in vitro. Little is known of the other types of PDGFRA mutations that occur in GISTs. MATERIALS AND METHODS: We determined the KIT and PDGFRA mutation status of 1,105 unique GISTs using a combination of denaturing high-performance liquid chromatography and direct sequencing. RESULTS: 66 in exon 18, 11 in exon 12, and three in exon 14. Transient expression of representative PDGFRA isoforms in CHO cells revealed imatinib sensitivity of exon 12 mutations (SPDHE566-571R and insertion ER561-562) and an exon 14 substitution (N659K). However, most isoforms with a substitution involving codon D842 in exon 18 (D842V, RD841-842KI, DI842-843IM) were resistant to the drug, with the exception of D842Y. Interestingly, other mutations in exon 18 (D846Y, N848K, Y849K and HDSN845-848P) were all imatinib sensitive. Proliferation studies with BA/F3 cell lines stably expressing selected PDGFRA mutant isoforms supported these findings. CONCLUSION: Including our cases, there are 289 reported PDGFRA-mutant GISTs, of which 181 (62.6%) had the imatinib-resistant substitution D842V. However, our findings suggest that more than one third of GISTs with PDGFRA mutations may respond to imatinib and that mutation screening may be helpful in the management of these tumors. 相似文献
75.
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78.
Hanna Tuovila Alexander R. Schmidt Christina Beimforde Heinrich Dörfelt Heinrich Grabenhorst Jouko Rikkinen 《Fungal Diversity》2013,58(1):199-213
Resin protects wounded trees from microbial infection, but also provides a suitable substrate for the growth of highly specialized fungi. Chaenothecopsis proliferatus is described growing on resin of Cunninghamia lanceolata from Hunan Province, China. The new fungus is compared with extant species and two new fossil specimens from Eocene Baltic and Oligocene Bitterfeld ambers. The Oligocene fossil had produced proliferating ascomata identical to those of the newly described species and to other extant species of the same lineage. This morphology may represent an adaptation to growing near active resin flows: the proliferating ascomata can effectively rejuvenate if partially overrun by fresh, sticky exudate. Inward growth of fungal hyphae into resin has only been documented from Cenozoic amber fossils suggesting comparatively late occupation of resin as substrate by fungi. Still, resinicolous Chaenothecopsis species were already well adapted to their special ecological niche by the Eocene, and the morphology of these fungi has since remained remarkably constant. 相似文献
79.
Mertens J Stock S Lüngen M V Berg A Kr?mer U Filipiak-Pittroff B Heinrich J Koletzko S Grübl A Wichmann HE Bauer CP Reinhardt D Berdel D Gerber A 《Pediatric allergy and immunology》2012,23(6):597-604
To cite this article: Mertens J, Stock S, Lüngen M, Berg AV, Kr?mer U, Filipiak-Pittroff B, Heinrich J, Koletzko S, Grübl A, Wichmann H-E, Bauer C-P, Reinhardt D, Berdel D, Gerber A. Is Prevention of Atopic Eczema with Hydrolyzed Formulas Cost-Effective? A Health Economic Evaluation from Germany. Pediatr Allergy Immunol 2012: 23: 597-604. ABSTRACT: Objective: The German Infant Nutritional Intervention (GINI) trial, a prospective, randomized, double-blind intervention, enrolled children with a hereditary risk for atopy. When fed with certain hydrolyzed formulas for the first 4?months of life, the risk was reduced by 26-45% in PP and 8-29% in intention-to-treat (ITT) analyses compared with children fed with regular cow's milk at age 6. The objective was to assess the cost-effectiveness of feeding hydrolyzed formulas. Patients and Methods: Cost-effectiveness was assessed with a decision tree model programmed in TreeAge. Costs and effects over a 6-yr period were analyzed from the perspective of the German statutory health insurance (SHI) and a societal perspective at a 3% effective discount rate followed by sensitivity analyses. Results: The extensively hydrolyzed casein formula would be the most cost-saving strategy with savings of 478?€ per child treated in the ITT analysis (CI95%: 12?€; 852?€) and 979?€ in the PP analysis (95%CI: 355?€; 1455?€) from a societal perspective. If prevented cases are considered, the partially whey hydrolyzed formula is cost-saving (ITT -5404?€, PP -6358?€). From an SHI perspective, the partially whey hydrolyzed formula is cost-effective, but may also be cost-saving depending on the scenario. An extensively hydrolyzed whey formula also included into the analysis was dominated in all analyses. Conclusions: For the prevention of AE, two formulas can be cost-effective or even cost-saving. We recommend that SHI should reimburse formula feeding or at least the difference between costs for cow's milk formula and the most cost-effective formula. 相似文献