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The quality of MRI will affect doctor's judgment on patient's physical conditions,and the high-resolution MRI is more conducive to doctor to make an accurate diagnosis.Using computer technology to perform super-resolution reconstruction of MRI can obtain high-resolution MRI from existing low-resolution MRI.Based on the strong generation ability of the generative adversarial networks and the unsupervised learning characteristics of the generative adversarial networks,this paper studies the MRI super-resolution algorithm based on the generative adversarial networks.It designs a generative adversarial network model DNGAN that combines ResNet structure and DenseNet structure.In this network,the WGAN-GP theory is used as the adversarial loss to stabilize the training of the generative adversarial networks.In addition,the content loss function and the perceptual loss function are also used as the loss function of the network.At the same time,in order to make better use of the rich frequency domain information of MRI,the frequency domain information of MRI is added to the network as a frequency domain loss function.In order to prove the effectiveness of DNGAN,the MRI super-resolution experimental results of DNGAN are compared with that of SRGAN and bicubic interpolation method.Experimental results show that DNGAN model can effectively perform super-resolution reconstruction of MRI.

Lung cancer is the most common cause of cancer-related mortality worldwide. It is necessary to improve the understanding of the molecular mechanisms involved in lung cancer in order to develop more effective therapeutics for the treatment of this fatal disease. The canonical Wnt signaling pathway has been known to be important in a number of cancer types, including lung cancer. Pygopus (Pygo) is a recently identified downstream component of the Wnt signaling pathway required for β-catenin/T-cell factor (TCF)-dependent transcription. However, the role of Pygo in lung cancer remains to be elucidated. The present study showed that Pygo2 is overexpressed in human lung cancer tissue samples and cell lines. Expression levels of Pygo2 were found to correlate with cytosolic β-catenin protein levels in the samples examined. Co-immunofluorescent staining showed that Pygo2 protein accumulated in the nuclei and colocalized with nuclear β-catenin in lung cancer cell lines expressing Pygo2. To investigate the functional importance of the Pygo2 overexpression in lung cancer, short hairpin RNA (shRNA) was used to knockdown Pygo2 mRNA in lung cancer cells expressing the gene. Pygo2 shRNA was observed to inhibit cell proliferation and decrease β-catenin/TCF-dependent transcriptional activity in vitro . Furthermore, Pygo2 shRNA significantly suppressed lung cancer xenograft models in vivo (P<0.05). These results suggested that Pygo2 is a putative therapeutic target for human lung cancer and overexpression of Pygo2 may be important for aberrant Wnt activation in lung cancer.

Objective: To explore the features of coronary atherosclerosis among the patients at different ages and examine their risk factors and pathological characteristics., Methods: Retrospective analysis was performed for the clinicopathologic data of 87 patients with coronary atherosclerosis confirmed through autopsy from February 1986 to December 2011 at our hospital. They were divided into 3 groups according to age (20 - < 40 years, n = 12; 40 - < 60 years, n = 24; ≥ 60 years, n = 51). Comparative analysis was performed for the degree of coronary artery stenosis and cardiac pathological changes, vulnerable plaque occurrence and morphological features of acute coronary syndrome among different patient groups., Results: There were 56 males and 31 females with a mean age of 66.8 years (range: 23 - 80). Great statistical differences existed in the degree of coronary artery stenosis between different genders (P < 0.05) while there was no significant difference among the above age groups (P > 0.05). In the above age groups of patients with acute coronary syndrome, the incidence of big lipid core was 23.5%, 38.5% and 53.8% (χ(2) = 6.282, P = 0.043), that of thin fibrous cap 29.4%, 41.0% and 58.8% (χ(2) = 6.589, P = 0.037), that of inflammatory cell in 2 filtration 58.8%, 69.2% and 85.0% (χ(2) = 7.435, P = 0.024) and that of calcification formation 35.3%, 56.4% and 71.3% respectively (χ(2) = 8.599, P = 0.014). And the incidence of vulnerable plaque occurrence was 76.5%, 84.6% and 88.8% (χ(2) = 1.850, P = 0.397) in the above age groups., Conclusions: The features and risk factors of coronary atherosclerosis are different according to different ages and genders. Thus we should pay more attention to the early diagnosis and reasonable treatments of young patients and those with both mild coronary stenosis and vulnerable plaque.

Objective: To evaluate the application of traditional cytomorphology, telomerase activity analysis and immunocytochemistry in cytopathologic diagnosis of pleural effusion and bronchoalveolar lavage samples., Methods: A total of 123 agar-paraffin double-embedded pleural effusion and bronchoalveolar lavage fluid samples were enrolled into study. The cytomorphologic features were reviewed and correlated with immunocytochemical findings and telomerase activity., Results: Telomerase activity was detected in 53 specimens using the real-time telomeric repeat amplification protocol. Amongst the cases studied, 39 samples (31.7%) contained overtly malignant cells while 20 cases (16.0%) were equivocal by conventional cytology. After verification by immunocytochemistry and clinical follow-up data, the diagnostic accuracy of telomerase activity and cytology was 87.0% and 82.1%, respectively. The sensitivity (97.6%) and specificity (100.0%) of cytology examination, when combined with telomerase activity analysis, were greater than those of cytology examination or telomerase activity analysis alone., Conclusions: Telomerase activity analysis can be used as an adjunctive investigative tool in cytology assessment of pleural effusion and bronchoalveolar lavage samples. The diagnostic accuracy can be further improved with the application of immunocytochemistry on agar-paraffin double-embedded cell block tissues.

Objective: To investigate the clinical autopsy results of patients died of cardiovascular disease or other disease complicated with cardiac damage., Methods: Complete autopsy was performed on 86 cases with uncertain cause of death. Through integrating clinical diagnosis and treatment with gross autopsy findings and microscopic observations, 86 autopsies were determined the major cause of death., Results: In 86 autopsies, 69 cases were heart disease. Differences between pathological diagnosis and clinical diagnosis were compared. Twenty-seven cases were cardiac deaths, with diagnosis accordance rate of 81.5%. Forty-two cases died of non-cardiac disease but complicated with heart disease or involving the heart which accelerated the death in patients, with accordance rate of 78.6%., Conclusion: Scientific and correct performance of autopsy was important to determine the causes of death, to promote development of related disciplines and to improve the diagnosis and treatment of the diseases.

Objective: To examine the expression of angiotensin II (Ang II) receptor subtypes in human left and right atrial tissue in atrial fibrillation underlying rheumatic heart disease., Methods: Atrial tissue samples were obtained from 39 patients with rheumatic heart disease, 25 with atrial fibrillation (AF) and 14 with sinus rhythm(SR) during open heart surgery. AT1 and AT2 mRNA levels were measured with semi-quantitative reverse transcription polymerase chain reaction techniques. AT1 and AT2 protein levels were measured with immunohistochemical techniques., Results: Compared with that of the SR group, left atrial inner diameter was significantly increased in the patients of the AF group. The AT1 mRNA and protein levels in the LA significantly increased in patients with AF compared with those in patients with SR (P < 0.05), whereas AT2 mRNA and protein were not significantly altered. Investigations of Ang II receptor subtypes' mRNA and protein levels in the RA did not exhibit any significant changes either in AT1 or AT2 in patients with AF and SR., Conclusions: AF is associated with an up-regulation of AT1 in LA, but does not appear to influence the AT2 expression. This may indicate a possible pathophysiologic role for renin-angiotensin system in the development of AF. The series of effects mediated by AT1 activation may be one of the molecular mechanisms involved in the process of atrial remodeling.

Objective: To investigate mutations of epidermal growth factor receptor (EGFR) exon 19 and 21 in non-small cell lung carcinoma and to explore their clinicopathological correlations., Method: DNA was extracted from the excised tumor specimens of 66 non-small cell lung carcinoma patients by traditional phenol-chloroform and ethanol precipitation. Exons 19 and 21 were amplified by polymerase chain reaction (PCR), followed by direct sequencing in both sense and antisense directions., Results: EGFR somatic mutations were present in 11 of 66 patients (16.7%), including 7 cases of in-frame deletion involving exon 19 and 4 cases of amino acid substitution involving exon 21. Mutations were more frequently observed in women (9/34, 26.5%) than in men (2/32, 6.3%), in adenocarcinomas (10/43, 23.3%) than squamous (0/13) and adenosquamous carcinomas (1/10). There was no difference in the mutation rates between smokers and non-smokers. Those with adenocarcinoma with bronchiolo-alveolar carcinoma (BAC) components had higher frequency of EGFR mutation (6/11) than those without non-BAC element (4/32, 12.5%)., Conclusions: The mutations appear to occur in highly selected subgroups of lung cancer patients: adenocarcinomas with BAC components and patients of the female gender. The results may offer practical approach to the rapid identification of lung cancer patients who likely respond to EGFR inhibitor therapy.

Objective: To study the role of Mycobacterium tuberculosis in the pathogenesis of sarcoidosis., Methods: Archival material of 22 patients with a histologic diagnosis of sarcoidosis were retrieved. Real-time fluorescent polymerase chain reaction (PCR) was used to detect DNA fragments of the complex-specific insertion sequence IS6110 of Mycobacterium tuberculosis in formalin-fixed and paraffin-embedded biopsy samples., Results: Among the 22 samples studied, Mycobacterium tuberculosis DNA was detected in 11 cases. The sequence of PCR amplified IS6110 DNA fragments completely matched with the related sequence in Mycobacterium tuberculosis gene., Conclusions: Mycobacterium tuberculosis DNA is identified in a certain proportion of patients with a clinicopathologic diagnosis of sarcoidosis. Mycobacterium tuberculosis may be an important etiologic agent, at least in some of these patients.

Background & Objective: Metastasis is one of the most important factors in determining the prognosis of lung cancer patients. However, it is difficult to determine single cancer cell in lymph nodes by routine methods. This study was designed to investigate a sensitive method for detecting lymph node micrometastases in human lung carcinomas., Methods: Mutation detection for p53 gene (exon 5-8) was performed in 39 cases of primary lung carcinomas and 110 corresponding lymph nodes (LNS) by PCR-TGGE method. Serial sectioning was performed to confirm micrometastases in some of these samples., Results: p53 mutations were found in 23 of 39 cases with primary lung cancer. Forty LNSs showed p53 mutation in 67 corresponding LNSs. They were located at the same exon as their primary tumors. Only twenty-six LNSs were detected metastases by routine histopathology. Forty-three LNSs from sixteen cases of primary tumor without p53 mutation and ten LNSs from the patients without tumor disease did not have any p53 mutations. By PCR-TGGE assay p53 gene mutations were determined in fourteen LNSs without histopathological evidence of metastasis. Micrometastases were found in four of the serially sectioned cases., Conclusion: Mutation detection for p53 gene (exon 5-8) showed lymph node micrometastases in patients with lung carcinoma. It may be used as a complement for the routine histopathology.