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21.
Mohammad Reza Abbaszadegan Hamid Reza Raziee Kamran Ghafarzadegan Mohammad Taghi Shakeri Sima Afsharnezhad Mohammad Reza Ghavamnasiry 《Journal of gastrointestinal cancer》2005,36(1):47-53
Aim. Detection of methylation in the p16 gene, an inhibitor of cyclin D-dependent protein kinase, as a new tumor marker for early detection of esophageal squamous
cell carcinoma (ESCC) in DNA derived from blood and serum.
Method. A large family with clustering of ESCC was assessed in Khorasan province in northeastern Iran. The family had three histologically
proven cases of ESCC in two consecutive generations and several other deceased cases with histories of ESCC. DNA from blood
of 28 living family members in three consecutive generations, 30 sporadic ESCC cases (from serum, blood, and tumor tissues),
and 30 healthy volunteers (from blood) were examined for the methylation status of p16 promoter using methylation-specific PCR (MSP).
Results. Aberrant p16 promoter methylation was found in 64.3% (n=28) of ESCC family members and none (n=30) of our normal volunteers. Five of the 28 family members with esophageal cancer symptoms had negative endoscopy results
for ESCC, while four of these members had p16 hypermethylation in their blood. The family members with negative endoscopy and positive p16 promoter methylation are being monitored closely for signs of ESCC development through regular check-ups and chromoendoscopies.
In sporadic ESCC in northeastern Iran, 73.3% (n=30) of tumor tissue samples had p16 hypermethylation. Serum and blood samples from the same patients showed p16 hypermethylation in 26.6% and 43.3% of the samples, respectively.
Conclusion. Aberrant p16 methylation may be a valuable diagnostic tool as a tumor marker for the early identification of individuals in high risk
ESCC families. 相似文献
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Tuan-Khoa Nguyen Hoang-Phuong Phan Jisheng Han Toan Dinh Abu Riduan Md Foisal Sima Dimitrijev Yong Zhu Nam-Trung Nguyen Dzung Viet Dao 《RSC advances》2018,8(6):3009
This paper presents for the first time a p-type 4H silicon carbide (4H-SiC) van der Pauw strain sensor by utilizing the strain induced effect in four-terminal devices. The sensor was fabricated from a 4H-SiC (0001) wafer, using a 1 μm thick p-type epilayer with a concentration of 1018 cm−3. Taking advantage of the four-terminal configuration, the sensor can eliminate the need for resistance-to-voltage conversion which is typically required for two-terminal devices. The van der Pauw sensor also exhibits an excellent repeatability and linearity with a significantly large output voltage in induced strain ranging from 0 to 334 ppm. Various sensors aligned in different orientations were measured and a high sensitivity of 26.3 ppm−1 was obtained. Combining these performances with the excellent mechanical strength, electrical conductivity, thermal stability, and chemical inertness of 4H-SiC, the proposed sensor is promising for strain monitoring in harsh environments.This paper presents for the first time a p-type 4H silicon carbide (4H-SiC) van der Pauw strain sensor by utilizing the strain induced effect in four-terminal devices. 相似文献
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Muscle infaction is a rare complication in patients with diabetes mellitus, probably because of the rich vascular supply of
this tissue. We describe a patient with type 1 diabetes who had infarction of the muscles in her right thigh. We report, for
the first time, that the patient, in addition to an advanced microvascular disease in the muscle, had increased plasma total
homocysteine levels and increased platelet aggregation. These pathologies might have a synergistic effect on the development
of this rare complication and should be treated aggrssively to prevent further episodes. 相似文献
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To determine the association of serum apolipoprotein (apo) A-I and B concentrations, and paraoxonase (PON) high-density lipoprotein (HDL) associated enzyme activity with angiographically determined coronary artery disease (CAD) in Iranian diabetic and non-diabetic CAD patients and non-diabetic control subjects, 251 subjects aged 30-70 years, who underwent their first coronary angiography were matched and randomly assigned into three groups: CAD(+)DM(+), CAD(+)DM(-), and CAD(-)DM(-) (control). Stenosis of > or =50% in one or more coronary arteries was classified as CAD(+). CAD(-) was defined as a maximum stenosis of 10% in any coronary artery. Fasting serum concentrations of cholesterol (TC), triglycerides (TGs), LDL-C, HDL-C, apo A-I/B and PON activity were determined. Apolipoprotein concentrations were measured in a fasting serum sample by immunoturbidometric assay and paraoxonase/arylesterase activities by spectrophotometric assay of p-nitrophenol/phenol production following addition of paraoxon/phenylacetate. Information concerning non-lipid risk factors were collected by questionnaires. No significant difference was observed in HDL-C, LDL-C, apo A-I, and PON/arylesterase activity between the study groups. The values of TC (213+/-38 vs 196+/-45, P<0.05), TGs (209+/-187 vs 151+/-113, P<0.01), apo B (99+/-22 vs 96+/-24, P<0.0001), TC/HDL-C (4.8+/-1.5 vs 4.0+/-1.3, P<0.001) and LDL-C/HDL-C (2.9+/-1.1 vs 2.4+/-1.1, P<0.05) were higher and apo A-I/B (1.7+/-0.4 vs 2.0+/-0.6, P<0.01) was lower in CAD(+)DM(+) patients than in control subjects. In CAD(+)DM(-) group, only the level of apo B (96+/-24 vs 85+/-18, P<0.01), and the ratio of apo A-I/B (1.8+/-0.4 vs 2.0+/-0.6, P<0.01), were significantly higher than those of control group. On multiple logistic regression analysis, the best markers for discrimination between CAD(+) groups and CAD(-) control subjects were the ratio of apo A-I/B in diabetic and apo B in non-diabetic patients. The results suggest that in Iranian diabetic and non-diabetic patients with CAD the concentration of apolipoproteins are better markers than traditional lipid parameters in discriminating between CAD(+) and CAD(-) subjects. Lack of significant difference in PON activity between CAD patients and CAD(-) controls supports the concept of interethnic variability in PON polymorphism and unimodal distribution of its activity in non-Europid populations observed in other studies. 相似文献
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