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Rey JW Hansen T Dümcke S Tresch A Kramer K Galle PR Goetz M Schuchmann M Kiesslich R Hoffman A 《World journal of gastrointestinal endoscopy》2014,6(4):137-143
AIM: To evaluate the diagnostic yield(inflammatory activity) and efficiency(size of the biopsy specimen) of SpyGlassTM-guided biopsy vs standard brush cytology in patients with and without primary sclerosing cholangitis(PSC).METHODS: At the University Medical Center Mainz, Germany, 35 consecutive patients with unclear biliarylesions(16 patients) or long-standing PSC(19 patients) were screened for the study. All patients underwent a physical examination, lab analyses, and abdominal ultrasound. Thirty-one patients with non-PSC strictures or with PSC were scheduled to undergo endoscopic retrograde cholangiography(ERC) and subsequent per-oral cholangioscopy(POC). Standard ERC was initially performed, and any lesions or strictures were localized. POC was performed later during the same session. The Boston Scientific SpyGlass SystemTM(Natick, MA, United States) was used for choledochoscopy. The biliary tree was visualized, and suspected lesions or strictures were biopsied, followed by brush cytology of the same area. The study endpoints(for both techniques) were the degree of inflammation, tissue specimen size, and the patient populations(PSC vs non-PSC). Inflammatory changes were divided into three categories: none, low activity, and high activity. The specimen quantity was rated as low, moderate, or sufficient.RESULTS: SpyGlassTM imaging and brush cytology with material retrieval were performed in 29 of 31(93.5%) patients(23 of the 29 patients were male). The median patient age was 45 years(min, 20 years; max, 76 years). Nineteen patients had known PSC, and 10 showed non-PSC strictures. No procedure-related complications were encountered. However, for both methods, tissues could only be retrieved from 29 pa-tients. In cases of inflammation of the biliary tract, the diagnostic yield of the SpyGlassTM-directed biopsies was greater than that using brush cytology. More tissue material was obtained for the biopsy method than for the brush cytology method(P = 0.021). The biopsies showed significantly more inflammatory characteristics and greater inflammatory activity compared to the cy-tological investigation(P = 0.014). The greater quantity of tissue samples proved useful for both PSC and non-PSC patients.CONCLUSION: SpyGlassTM imaging can be recom-mended for proper inflammatory diagnosis in PSC pa-tients. However, its value in diagnosing dysplasia wasnot addressed in this study and requires further investi-gation. 相似文献
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Al2O3 films were prepared by the aerosol deposition method at room temperature using different carrier gas compositions. The layers were deposited on alumina substrates and the film stress of the layer was calculated by measuring the deformation of the substrate. It was shown that the film stress can be halved by using oxygen instead of nitrogen or helium as the carrier gas. The substrates were annealed at different temperature steps to gain information about the temperature dependence of the reduction of the implemented stress. Total relaxation of the stress can already be achieved at 300 °C. The XRD pattern shows crystallite growth and reduction of microstrain while annealing. 相似文献
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Johanna I. Kiiski Liisa M. Pelttari Sofia Khan Edda S. Freysteinsdottir Inga Reynisdottir Steven N. Hart Hermela Shimelis Sara Vilske Anne Kallioniemi Johanna Schleutker Arto Leminen Ralf Bützow Carl Blomqvist Rosa B. Barkardottir Fergus J. Couch Kristiina Aittom?ki Heli Nevanlinna 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(42):15172-15177
Inherited predisposition to breast cancer is known to be caused by loss-of-function mutations in BRCA1, BRCA2, PALB2, CHEK2, and other genes involved in DNA repair. However, most families severely affected by breast cancer do not harbor mutations in any of these genes. In Finland, founder mutations have been observed in each of these genes, suggesting that the Finnish population may be an excellent resource for the identification of other such genes. To this end, we carried out exome sequencing of constitutional genomic DNA from 24 breast cancer patients from 11 Finnish breast cancer families. From all rare damaging variants, 22 variants in 21 DNA repair genes were genotyped in 3,166 breast cancer patients, 569 ovarian cancer patients, and 2,090 controls, all from the Helsinki or Tampere regions of Finland. In Fanconi anemia complementation gene M (FANCM), nonsense mutation c.5101C>T (p.Q1701X) was significantly more frequent among breast cancer patients than among controls [odds ratio (OR) = 1.86, 95% CI = 1.26–2.75; P = 0.0018], with particular enrichment among patients with triple-negative breast cancer (TNBC; OR = 3.56, 95% CI = 1.81–6.98, P = 0.0002). In the Helsinki and Tampere regions, respectively, carrier frequencies of FANCM p.Q1701X were 2.9% and 4.0% of breast cancer patients, 5.6% and 6.6% of TNBC patients, 2.2% of ovarian cancer patients (from Helsinki), and 1.4% and 2.5% of controls. These findings identify FANCM as a breast cancer susceptibility gene, mutations in which confer a particularly strong predisposition for TNBC.Breast cancer is the most common cancer affecting women worldwide. It is also the principal cause of death from cancer among women globally, accounting for 14% of all cancer deaths (1). The etiology of breast cancer is multifactorial, and the risk depends on various factors like age, family history, and reproductive, hormonal, or dietary factors. The majority of breast cancers are sporadic, but approximately 15% of cases show familial aggregation (2, 3). Since the identification of the first breast and ovarian cancer susceptibility genes breast cancer 1 and 2 (BRCA1 and BRCA2, respectively) by linkage analysis and positional cloning, several breast cancer susceptibility genes and alleles with different levels of risk and prevalence in the population have been recognized. BRCA1 and BRCA2 mutation carriers have more than 10-fold increased risk of breast cancer compared with women in the general population, and mutations in TP53, PTEN, STK11, and CDH1 have also been associated with a high lifetime risk of breast cancer in the context of rare inherited cancer syndromes (4). In addition, rare variants in genes such as checkpoint kinase 2 (CHEK2), ataxia telangiectasia mutated (ATM), and BRCA1 interacting helicase BRIP1, that confer a two- to fourfold increased risk, and in partner and localizer of BRCA2 (PALB2), with even higher risk estimates, have been found with candidate gene approaches (5, 6), and an increasing number of common low-risk loci with modest odds ratios (ORs; as much as 1.26-fold increased risk for heterozygous carriers) have been identified by genome-wide association studies (7).However, the major portion of hereditary breast cancer still remains unexplained, and many susceptibility loci are yet to be found. Exome sequencing combined with genotyping of the identified variants in case-control analysis is an effective method to recognize novel risk alleles, based on the assumption that disease-causing variants are rare and often accumulate in the protein-coding areas of the genome (8–10).Since the discovery that proteins encoded by the BRCA1 and BRCA2 breast/ovarian cancer susceptibility genes are directly involved in homologous recombination repair of DNA double-strand breaks, it has been evident that other genes involved in DNA repair are attractive breast cancer susceptibility candidates (4). Biallelic mutations in ATM gene cause rare ataxia telangiectasia disease and are associated with an increased risk for breast cancer as a result of improper DNA damage response (11). Fanconi anemia (FA) is a rare genetic disorder caused by biallelic mutations in FA genes that also participate in DNA repair. At least 15 FA genes have been identified (12). Patients with heterozygous mutations in certain FA genes have an elevated risk for various cancers, and monoallelic mutations in at least four of these genes [BRCA2, BRIP1, PALB2, and RAD51 paralog C (RAD51C)] are associated with an increased risk of breast or ovarian cancer (12, 13). Recurrent founder mutations in several cancer susceptibility genes, including the BRCA2, PALB2, and RAD51C FA genes, have been identified in the Finnish population (14–16). The PALB2 and RAD51C founder mutations have been detected at 2% frequency in Finnish breast or ovarian cancer families (15–17), whereas, in other populations, mutations in these genes are rare and often unique for each family. Founder effects in the isolated populations such as Finland or Iceland may enrich certain mutations and thus explain a significant proportion of all mutations in certain genes (18, 19). This provides an advantage in the search for novel susceptibility genes and alleles.In this study, we used exome sequencing to uncover previously unidentified recurrent breast or ovarian cancer predisposing variants in the Finnish population with a focus on DNA repair genes. Selected variants were further genotyped in a large case-control sample set. Our investigation revealed an association of a nonsense mutation (rs147021911) in an FA complementation gene, FANCM, with breast cancer, especially with triple-negative (TN) breast cancer (TNBC). 相似文献
156.
Verena Limperger Ulrich C. Klostermeier Gili Kenet Susanne Holzhauer Martine Alhenc Gelas Ulrich Finckh Ralf Junker Christine Heller Barbara Zieger Karin Kurnik Ralf Knöfler Rolf Mesters Susan Halimeh Ulrike Nowak‐Göttl 《British journal of haematology》2014,167(3):385-393
Venous thromboembolism [TE] is a multifactorial disease and protein C deficiency [PCD] constitutes a major risk factor. In the present study the prevalence of PCD and the clinical presentation at TE onset, including neonatal purpura fulminans, in a cohort of children are reported. In 367 unselected children (0·1–19 years) recruited between July 1996 and December 2013, a comprehensive thrombophilia screening was performed along with recording of anamnestic data. Twenty‐five of 338 children (7·4%) had PCD. Mean age at first TE onset was 10 years (range 0·1–18). Leading thromboembolic manifestations were neonatal purpura fulminans (n = 5), TE of cerebral veins (n = 3), stroke (n = 2) deep veinthrombosis (DVT) of the leg (n = 10), DVT & pulmonary embolism (n = 2) and DVT & pelvic veins (n = 3). Concomitant risk factors for TE were identified in 12 patients, whereas 13 children spontaneously developed TE. A positive family history of DVT was found in 10 children. In this unselected cohort of paediatric patients with symptomatic TE the overall prevalence of PCD was 7·4%; 1·5% presented with neonatal purpura fulminans. Given its clinical implication for patients and family members, thrombophilia testing should be performed and the benefit of medical or educational interventions should be evaluated in this high‐risk population. 相似文献
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Brunner R Aissaoui H Boss C Bozdech Z Brun R Corminboeuf O Delahaye S Fischli C Heidmann B Kaiser M Kamber J Meyer S Papastogiannidis P Siegrist R Voss T Welford R Wittlin S Binkert C 《The Journal of infectious diseases》2012,206(5):735-743
The increasing spread of drug-resistant malaria strains underscores the need for new antimalarial agents with novel modes of action (MOAs). Here, we describe a compound representative of a new class of antimalarials. This molecule, ACT-213615, potently inhibits in vitro erythrocytic growth of all tested Plasmodium falciparum strains, irrespective of their drug resistance properties, with half-maximal inhibitory concentration (IC(50)) values in the low single-digit nanomolar range. Like the clinically used artemisinins, the compound equally and very rapidly affects all 3 asexual erythrocytic parasite stages. In contrast, microarray studies suggest that the MOA of ACT-213615 is different from that of the artemisinins and other known antimalarials. ACT-213615 is orally bioavailable in mice, exhibits activity in the murine Plasmodium berghei model and efficacy comparable to that of the reference drug chloroquine in the recently established P. falciparum SCID mouse model. ACT-213615 represents a new class of potent antimalarials that merits further investigation for its clinical potential. 相似文献