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81.
BACKGROUND & AIMS: Detection of tumor-derived DNA alterations in stool is an intriguing new approach with high potential for the noninvasive detection of colorectal cancer (CRC). Because of heterogeneity of tumors, usually multiple markers distributed throughout the human genome need to be analyzed. This is labor intensive and does not allow for high through-put screening. Therefore, markers with high sensitivity and good specificity are needed. We explored the potential of a single epigenetic marker in comparison with fecal occult blood testing (FOBT) for the discrimination of patients with CRCs and adenomas from those without. METHODS: Methylation-specific polymerase chain reaction (PCR) was performed to analyze hypermethylated in cancer 1 (HIC1) promoter methylation status in a blinded fashion in stool samples from 26 patients with CRC, 13 with adenoma > or =1 cm, 9 with hyperplastic polyps, 9 with chronic inflammatory bowel disease, and 32 with endoscopically normal colon. RESULTS: Ninety-seven percent of the stool samples contained amplifiable DNA. Forty-two percent of the samples from patients with CRC and 31% of the samples from patients with colorectal adenoma > or =1 cm were positive for HIC1 promoter methylation. No methylated HIC1 promoter DNA was detected in the fecal DNA from patients with endoscopically normal colon or hyperplastic polyps. CONCLUSIONS: The epigenetic marker HIC1 promoter methylation carries high potential for the remote detection of CRCs. We postulate that a panel of merely a few genetic and epigenetic markers will be required for the highly sensitive and specific detection of CRCs and adenomas in fecal samples from affected patients.  相似文献   
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Protein disulfide isomerases (PDIs) catalyze the correct folding of proteins and prevent the aggregation of unfolded or partially folded precursors. Whereas suppression of members of the PDI gene family can delay replication of several human and animal viruses (e.g., HIV), their role in interactions with plant viruses is largely unknown. Here, using a positional cloning strategy we identified variants of PROTEIN DISULFIDE ISOMERASE LIKE 5–1 (HvPDIL5-1) as the cause of naturally occurring resistance to multiple strains of Bymoviruses. The role of wild-type HvPDIL5-1 in conferring susceptibility was confirmed by targeting induced local lesions in genomes for induced mutant alleles, transgene-induced complementation, and allelism tests using different natural resistance alleles. The geographical distribution of natural genetic variants of HvPDIL5-1 revealed the origin of resistance conferring alleles in domesticated barley in Eastern Asia. Higher sequence diversity was correlated with areas with increased pathogen diversity suggesting adaptive selection for bymovirus resistance. HvPDIL5-1 homologs are highly conserved across species of the plant and animal kingdoms implying that orthologs of HvPDIL5-1 or other closely related members of the PDI gene family may be potential susceptibility factors to viruses in other eukaryotic species.Infectious diseases caused by plant viruses threaten agricultural productivity and reduce globally attainable agricultural production by about 3% (1). In specific pathosystems, plant viruses can result in the loss of the entire crop. For example, the devastation of cassava production by cassava mosaic geminiviruses (CMGs) in Uganda during the 1990s led to widespread food shortages and famine-related deaths (2). Unfortunately protecting plants against viruses (especially soil-borne viruses) by using agrochemicals to control virus vectors is seldom efficient from economic or ecological perspectives. Therefore, crop protection based on naturally occurring virus resistance is key to minimizing losses and achieving sustainable crop yields.Positive-strand RNA viruses represent the largest group of plant viruses (3). They cause a very high proportion of the important infectious virus diseases in agriculture (4, 5). Such plant viruses carry a reduced genome that encodes a limited set of functional proteins (4–10 viral proteins)—insufficient to complete the entire virus replication and proliferation cycle (6). Instead, over evolutionary time, viruses recruited host factors to perform the infectious life cycle (7). This dependence on host factors establishes a possibility that plants can evolve escape, tolerance, or resistance mechanisms to ameliorate the consequences of viral infection. The absence of essential host factors could interfere with the infection process or restrict proliferation (8) leading to either mono- or polygenic recessive resistance (5). Prominent examples of such susceptibility factors that are conserved in multiple plant–virus systems are the EUKARYOTIC TRANSLATION INITIATION FACTORS (EIF)4E, iso4E, 4G, and iso4G (9). Translation initiation factors may interact directly with viral RNA where they catalyze the initiation of translation of viral polyproteins (10, 11). In addition, to establish replication and assembly complexes during infection, viruses typically create membrane-bound environments, referred to as “virus factories” (12). There, cellular chaperones such as HSP70 and DNAJ-like proteins likely contribute to the correct folding and translocation of substrates (12, 13). However, only a few such host factors are known (7, 9, 14).Barley yellow mosaic virus disease caused by barley yellow mosaic virus (BaYMV) and barley mild mosaic virus (BaMMV) (both belong to Bymoviruses) seriously threatens winter barley production in Europe and East Asia (4). Infection leads to yellow discoloration and stunted growth and may result in yield loss of up to 50% (15). Soil-borne transmission via the plasmodiophorid Polymyxa graminis prohibits plant protection by chemical measures, and breeding for resistant cultivars is therefore the only practicable way to prevent yield loss. The naturally occurring recessive resistance locus rym11 confers complete broad-spectrum resistance to all known European isolates of BaMMV and BaYMV (1619). In the present study, we used a positional cloning strategy to identify the gene underlying rym11-based resistance. We show that it is a susceptibility factor belonging to a gene family of PROTEIN DISULFIDE ISOMERASES (PDIs), and is highly conserved across eukaryotic species. We observe a strong correlation between natural allelic variation and geographic distribution, suggesting that both the origin and subsequent adaptive selection for rym11-based resistance in winter barley occurred in East Asia.  相似文献   
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Over the last years, electronic cigarettes (ECs) have become more popular, particularly in individuals who want to give up smoking tobacco. The aim of the present study was to assess the influence of the different e-smoking liquids on the viability and proliferation of human periodontal ligament fibroblasts. For this study six test solutions with components from ECs were selected: lime-, hazelnut- and menthol-flavored liquids, nicotine, propylene glycol, and PBS as control group. The fibroblasts were incubated up to 96 h with the different liquids, and cell viability was measured by using the PrestoBlue® reagent, the ATP detection and the migration assay. Fluorescence staining was carried out to visualize cell growth and morphology. Data were statistically analyzed by two-tailed one-way ANOVA. The cell viability assay showed that the proliferation rates of the cells incubated with nicotine or the various flavored liquids of the e-cigarettes were reduced in comparison to the controls, though not all reductions were statistically significant. After an incubation of 96 h with the menthol-flavored liquid the fibroblasts were statistically significant reduced (p?相似文献   
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Monatsschrift Kinderheilkunde - Eine adäquate Energie- und Nährstoffversorgung ist Grundlage für ein gesundes Wachstum und Voraussetzung für die Erhaltung von Gesundheit und...  相似文献   
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CSF detection of the 14-3-3 protein in unselected patients with dementia   总被引:9,自引:0,他引:9  
OBJECTIVE: To determine the usefulness of the 14-3-3 test in patients with dementia of various causes. BACKGROUND: Recent reports have suggested that the detection of the 14-3-3 protein in the CSF of patients with Creutzfeldt--Jakob disease is a highly sensitive and specific marker of the disease that might be used as a diagnostic criterion. We examined the validity of this test when applied to a cohort of unselected patients prospectively examined for an ongoing dementing process. METHODS: One hundred patients underwent an extensive neurologic examination for dementia, including a CSF 14-3-3 protein immunoblotting assay. Final clinical diagnoses were compared with the qualitative results of the test, and statistical measures of test validity were carried out. RESULTS: We found a positive test in 14 of 100 patients, only two of whom had definite Creutzfeldt--Jakob disease. Positive results were found in patients with various degenerative dementias, including AD (4), frontotemporal dementia (2), and dementia with Lewy body (1), and in patients with vascular dementia (1), carcinomatous meningitis (1), and anoxic encephalopathy (1). In two other positive patients, the dementia could not be confidently classified. Sensitivity, specificity, and negative predictive value were fairly good, but positive predictive value was poor. Similar results were found independently of the disease duration. There was no correlation between intensity nor pattern of the 14-3-3 protein expression and diagnosis. CONCLUSIONS: The 14-3-3 test is not valid for discriminating between Creutzfeldt--Jakob disease and non-Creutzfeldt--Jakob disease in unselected patients with dementia. Positive results are found in various degenerative and secondary, prion-unrelated dementias.  相似文献   
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Surgical management of esophagogastric junction tumors   总被引:3,自引:0,他引:3  
INTRODUCTION Different tumor entities arise in the vicinity of the esophagogastric junction. The appropriate classification of these entities is essential for choosing the appropriatesurgical approach and making results from different instutions comparabl…  相似文献   
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