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61.
Papillary thyroid carcinoma (PTC) is the most common malignant thyroid tumor, and 36-69% of PTC cases are caused by mutations in the BRAF gene. The substitution of a valine for a glutamic acid (V600E) comprises up to 95-100% of BRAF mutations; therefore, most diagnostic methods, including allele-specific PCR and real-time PCR, are designed to detect this mutation. Nevertheless, other mutations can also comprise the genetic background of PTC. Recently, a novel and sensitive technique called mutant enrichment with 3'-modified oligonucleotides (MEMO) PCR has been introduced. When we applied allelespecific PCR and MEMO-PCR for the detection of the BRAF V600E mutation, we found an unusual 3' bp deletion mutation (c.1799_1801delTGA) only when using MEMO-PCR. This deletion results in the introduction of a glutamic acid into the B-Raf activation segment (p.V600_K601delinsE), leading to an elevated basal kinase activity of BRAF. This is the first report of a rare 3 bp BRAF deletion in a PTC patient that could not be detected by allele-specific PCR. 相似文献
62.
Purpose
To evaluate the inter-observer variability of stenosis measurements by using multi-directional 3D reconstructed projection view of internal carotid artery (ICA) that simulate the pre-determined stenosis degree on magnetic resonance angiography (MRA) image sequence of phantom data set and to compare the difference in measured percentages of maximum ICA stenosis between projection and axial images.Materials and methods
By using adaptive region growing and circumscribed quadrangle on the clinical data set, the cylinder shape of a mathematical phantom was modeled and implemented. The maximum ICA stenosis was categorized as mild (30%), moderate (50%), and severe (70%) stenosis those simulated on the tomographic image sequence of ICA only and synthesized phantom. The 36 maximum intensity projection (MIP) images were radially projected at 10° increments that were rotated about the long axis of the body by using the simulated stenosis degree on the tomographic image sequence of phantom data sets. The six different projection image data sets were used to measure the minimum residual lumen and reference diameter by three blinded observers. The percentage of maximum ICA stenosis was calculated as the following. The ICA stenosis grading was [1 − (minimum residual lumen/averaged reference diameter)] × 100%.Results
The percentage of maximum ICA stenosis degree measured on projection image was underestimated on ICA only phantom and overestimated on synthesized phantom compared to the simulated ICA stenosis degree on the axial image. In addition, the synthesized phantom provided the less projection image for stenosis measurement than ICA only phantom. These results attributed to the nature of MIP algorithm and the overlapping effects of surrounded anatomic structures such as other ICA, pair of external carotid artery (ECA), pair of VA, and background tissues. Furthermore, the inter-observer variability was also introduced by manual measurement.Conclusion
The automated scheme is recommended to measure the ICA stenosis by using axial image. This technique is not only accurate as possible but also robust, simple to handle, and less time consuming compared with manual measurements. A computerized ICA stenosis measuring method, which applied the image processing technique on the axial image, is necessary to overcome the drawbacks introduced by using the projection image and manual measurement. 相似文献63.
Eom SY Zhang YW Kim SH Choe KH Lee KY Park JD Hong YC Kim YD Kang JW Kim H 《Cancer causes & control : CCC》2009,20(2):137-145
Objectives We investigated the association of genetic polymorphisms of NQO1, ALDH2, CYP2E1, and the combined genotype of these genes on lung cancer risk, and also evaluated the association after stratification by
cumulative smoking amounts and alcohol drinking levels.
Methods The case–control study was performed in 387 lung cancer patients and 387 age- and sex-matched cancer-free controls. Direct
interview was conducted and the genotypes of NQO1, ALDH2, and CYP2E1 were investigated using PCR-RFLP or 5′-nuclease activity assay.
Results The proportion of individuals with occupational history of mining was significantly higher in cases than in controls. The
risk of lung cancer was significantly lower in light-drinkers (<108 g/week) than non-drinkers. The NQO1 Pro/Ser + Ser/Ser genotype showed an increased risk for lung cancer with a marginal significance (OR = 1.35, 95% CI = 0.99–1.86)
compared with NQO1 Pro/Pro genotype. In heavy-smokers, the combination of NQO1 Pro/Ser + Ser/Ser and CYP2E1 c1/c1 genotype was associated with a significantly increased risk for lung cancer (OR = 2.25, 95% CI = 1.14–4.43) compared
with those of NQO1 Pro/Pro and CYP2E1 c1/c2 + c2/c2 genotype. We found a significant interaction between alcohol drinking level and the CYP2E1 genotype (P = 0.0227).
Conclusions Our result suggests that the risk of lung cancer is affected by smoking, alcohol drinking, and the genetic polymorphism of
NQO1. In particular, genetic polymorphisms for NQO1, CYP2E1, and ALDH2 synergistically with cumulative smoking amounts and alcohol drinking levels interact in the carcinogenesis of lung cancer
in Koreans. 相似文献
64.
Myung Jin Jee Soon Man Yoon Eui Joong Kim Hyun-Jung Choi Jong-Won Kim Ro Hyun Sung Joung Ho Han Hee Bok Chae Seon Mee Park Sei Jin Youn 《Gut and liver》2013,7(6):747-751
Familial juvenile polyposis (FJP) is a rare autosomal dominant hereditary disorder that is characterized by the development of multiple distinct juvenile polyps in the gastrointestinal tract and an increased risk of cancer. Recently, germline mutations, including mutations in the SMAD4, BMPR1A, PTEN and, possibly, ENG genes, have been found in patients with juvenile polyps. We herein report a family with juvenile polyposis syndrome (JPS) with a novel germline mutation in the SMAD4 gene. A 21-year-old man presented with rectal bleeding and was found to have multiple polyps in his stomach, small bowel, and colon. His mother had a history of gastrectomy for multiple gastric polyps with anemia and a history of colectomy for colon cancer. A review of the histology of the polyps revealed juvenile polyps in both patients. Subsequently, mutation screening in DNA samples from the patients revealed a germline mutation in the SMAD4 gene. The pair had a novel mutation in exon 10 (stop codon at tyrosine 413). To our knowledge, this mutation has not been previously described. Careful family history collection and genetic screening in JPS patients are needed to identify FJP, and regular surveillance is recommended. 相似文献
65.
66.
67.
Jong Seok Bae Chang-Seok Ki Jong-Won Kim Byoung Joon Kim 《Journal of clinical neuroscience》2007,14(1):89-92
Oculopharyngeal muscular dystrophy (OPMD) is a late-onset muscle disorder characterized by progressive dysphagia and bilateral ptosis. Mutations in the polyadenylate binding protein nuclear 1 (PABPN1) gene have been found to cause OPMD. The typical mutation is a stable trinucleotide repeat expansion in the first exon of the PABPN1 gene, in which (GCG)(6) is the normal repeat length. We investigated a Korean patient with OPMD and identified a novel mutation: a heterozygous insertion of a 9-bp sequence [(GCG)(GCA)(GCA); c.27_28insGCGGCAGCA] instead of the (GCG) repeat expansion, resulting in an in-frame insertion of three alanines (p.A10insAAA). To the best of our knowledge, this is the first report of a genetically confirmed case of OPMD in Korea. 相似文献
68.
Tae Joo Jeon Jong Doo Lee Jong-Won Ha Woo Ick Yang Sang Ho Cho 《European journal of nuclear medicine and molecular imaging》2000,27(6):686-693
Doxorubicin is one of the most useful anticancer agents, but its repeated administration can induce irreversible cardiomyopathy
as a major complication. The purpose of this study was to investigate doxorubicin toxicity on cardiac sympathetic neurons
using iodine-131-metaiodobenzylguanidine (MIBG) and protein gene product (PGP) 9.5 immunohistochemistry, which is a marker
of cardiac innervation. Wistar rats were treated with doxorubicin (2 mg/kg, i.v.) once a week for 4 (n=5), 6 (n=6) or 8 (n=7) weeks consecutively. Left ventricular ejection fraction (LVEF), calculated by M-mode echocardiography, was used as an
indicator of cardiac function. Plasma noradrenaline (NA) concentration was measured by high-performance liquid chromatography
(HPLC). 131I-MIBG uptake of the left ventricular wall (24 ROIs) was measured by autoradiography. 131I-MIBG uptake pattern was compared with histopathological results, the neuronal population on PGP 9.5 immunohistochemistry
and the degree of myocyte damage assessed using a visual scoring system on haematoxylin and eosin and Masson’s trichrome staining.
LVEF was significantly decreased in the 8-week group (P<0.05). The serum NA level also showed no statistical difference until 4 weeks and was significantly increased in the 8-week
group (P<0.05). MIBG uptake was decreased in the 6- and 8-week groups (P<0.05), and was closely correlated with the reduction in the number of nerve fibres on PGP 9.5 stain. Myocyte damage was seen
only in the 8-week group. Neuronal population and the 131I-MIBG uptake ratio of subepicardium to subendocardium were significantly increased (P<0.05) in the 8-week group as compared with the control group. It may be concluded that radioiodinated MIBG is a reliable
marker for the detection of cardiac adrenergic neuronal damage in doxorubicin-induced cardiomyopathy; it detects such damage
earlier than do other clinical parameters and in this study showed a good correlation with the reduction in the neuronal population
on PGP 9.5 stain. The subendocardial layer appeared to be more vulnerable to doxorubicin than the subepicardium.
Received 14 December 1999 and in revised form 2 February 2000 相似文献
69.
70.
Ji Hyun Yoon Jung Woo Son Hyemoon Chung Chul Hwan Park Young-Jin Kim Hyuk-Jae Chang Geu-Ru Hong Tae Hoon Kim Jong-Won Ha Byoung Wook Choi Se-Joong Rim Namsik Chung Eui-Young Choi 《Korean journal of radiology》2015,16(5):1153-1162
ObjectivePost-contrast T1 values are closely related to the degree of myocardial extracellular space expansion. We determined the relationship between post-contrast T1 values and left ventricular (LV) diastolic function, LV remodeling, and neurohormonal activation in patients with dilated cardiomyopathy (DCM).ResultsThe mean LV ejection fraction was 24 ± 9% and the post-T1 value was 254.5 ± 46.4 ms. The post-contrast T1 value was significantly correlated with systolic longitudinal septal velocity (s''), peak late diastolic velocity of the mitral annulus (a''), the diastolic elastance index (Ed, [E/e'']/stroke volume), LV mass/volume ratio, LV end-diastolic wall stress, and LV end-systolic wall stress. In a multivariate analysis without NT-proBNP, T1 values were independently correlated with Ed (β = -0.351, p = 0.016) and the LV mass/volume ratio (β = 0.495, p = 0.001). When NT-proBNP was used in the analysis, NT-proBNP was independently correlated with the T1 values (β = -0.339, p = 0.017).ConclusionPost-contrast T1 is closely related to LV remodeling, diastolic function, and neurohormonal activation in patients with DCM. 相似文献