[Expression of miRNA let-7a and HMGA2 and Diagnostic Value of Serum miRNA let-7a Level in Pancreatic Cancer].

OBJECTIVE: To investigate the diagnostic value of miRNA let-7a, high mobility group A2 (HMGA2) expression and serum miRNA let-7a level in pancreatic cancer. METHODS: From January 2014 to January 2019, 60 patients with pancreatic cancer were collected for fresh pancreatic ductal adenocarcinoma tissue and normal pancreatic tissue adjacent to the cancer after the operation. Serum samples before and after operation were also collected, while 60 healthy people were enrolled as the control group. The expression of miRNA let-7a (qRT-PCR) and HMGA2 (qRT-PCR and Western blot) in cancer and adjacent normal tissues were measured. The serum level of miRNA let-7a was detected by qRT-PCR. The relationship between miRNA let-7a and HMGA2 expression and the clinicopathological features of pancreatic cancer was analyzed. The diagnostic value of serum miRNA let-7a pre-operation in patients with pancreatic cancer was also analyzed with ROC curve. RESULTS: Compared with normal tissues adjacent to the cancer, the expression level of miRNA let-7a in pancreatic cancer tissues decreased ( t=20.291, P<0.01), and the expression of HMGA2 mRNA increased ( t=46.681, P<0.01). The expression of HMGA2 protein in cancer tissues was higher than that in normal tissues adjacent to the cancer ( t=22.973, P<0.01). The serum level of miRNA let-7a in pancreatic cancer patients was significantly lower than that in healthy controls ( t=24.854, P<0.01). The relative level of serum miRNA let-7a at 1 week after surgery was significantly lower than that before surgery in pancreatic cancer patients ( t=6.885, P<0.01). There was a positive correlation between cancer tissue and serum miRNA let-7a expression 1 week after surgery ( r=0.411, P=0.000). The relative expression levels of miRNA let-7a and HMGA2 in pancreatic cancer tissues were significantly different in different TNM stages and lymph node metastasis ( P<0.05). The area under curve of pre-operation serum miRNA let-7a for the diagnosis of pancreatic cancer was 0.823 ( 95% confidence interval: 0.665-0.917); when the optimal cut-off value of miRNA let-7a was 0.614, the sensitivity was 82.3%, the specificity was 74.1%. CONCLUSION: The expression of HMGA2 may be involved in the invasion and metastasis of pancreatic cancer. The level of serum miRNA let-7a may provide a reference for the diagnosis and postoperative monitoring of pancreatic cancer.

[Survival analysis of patients with spontaneous rupture of hepatocellular carcinoma].

OBJECTIVE: To explore the prognostic factors influencing overall survival (OS) in patients with spontaneous rupture of hepatocellular carcinoma (HCC-SR). METHODS: The medical records of 44 patients with HCC-SR treated in our department from January 1, 2005 to April 1 2011 were retrospectively reviewed. The clinical and prognostic data of 19 HCC-SR patients who received curative hepatectomy were compared with data of 137 HCC patients with no SR who were managed by curative hepatectomy during the same period. Type of HCC-SR was defined according to previously established criteria. The clinicopathological data were evaluated for possible associations with OS of HCC-SR by univariate analysis with the Kaplan-Meier method followed by multivariate analysis with the Cox proportional hazard model. RESULTS: While some clinical features differed between the HCC-SR patients and non-HCC-SR patients, the postoperative prognosis was comparable between the two groups: (1) The 1-, 2-, 3- and 5-year postoperative cumulative recurrence rates were 78.9% (15/19), 89.5% (17/19), 94.7% (18/19) and 94.7% (18/19) in the HCC-SR group but 43.1% (59/137), 54.0% (74/137), 59.1% (81/137) and 66.4% (91/137) in the non-HCC-SR group respectively, and the differences reached statistical significance (P = 0.006, 0.003, 0.002, and 0.014); (2) The 1-, 2-, 3- and 5-year postoperative disease-free survival rates were 10.5% (2/19), 5.3% (1/19), 5.3% (1/19) and 5.3% (1/19) in the HCC-SR group but 40.1% (55/137), 21.2% (29/137), 12.4% (17/137) and 4.4% (6/137) in the non-HCC-SR group respectively, and only the 1-year disease-free survival rate was significantly different (P = 0.032); (3) The 1-, 2-, 3- and 5-year postoperative OS rates were 42.1% (8/19), 10.5% (2/19), 5.3% (1/19) and 5.3% (1/19) in the HCC-SR group but 59.1% (81/137), 32.8% (45/137), 19.0% (26/137) and 6.6% (9/137) in the non-HCC-SR group, and none of the differences reached statistical significance (P = 1.972, 0.061, 0.200, 1.000). Multivariate analysis identified that severity of concomitant liver cirrhosis, levels of alpha fetoprotein (AFP), choice of treatment modality, and type of HCC-SR acted as factors influencing OS. CONCLUSIONS: Patients with HCC-SR receiving curative hepatectomy have higher postoperative recurrence rates than their non-HCC-SR counterparts, but the two groups have similar postoperative OS rates. OS is influenced by severity of concomitant liver cirrhosis, level of AFP, choice of treatment modality, and type of HCC-SR.

[Fluorescence spectrum monitor for early warning of greenhouse cucumber aphis pests].

The infection and degree of cucumber aphis pests was studied by analyzing chlorophyllfluorescence spectrum in greenhouse. Based on the configuration of the spectrum, characteristic points were established, in which the intensity of waveband F632 was the first characteristic point between healthy and aphis pests leaves. The second characteristic point was K which was the change rate of spectral curve from waveband F512 to F632. The early warning could be executed on plants depending on these two points. The models of the infection and degrees of aphis pests were established for different wavebands by the least square support vector machine classification method (LSSVMR) radial basis function(RBF). The accuracy rate of classification and prediction of the models was compared by different peaks and valleys value in wavebands. The results indicated that the prediction accuracy of the model established by waveband F632 was the most perfect (96.34%).

[Chlorophyll fluorescence spectrum analysis of greenhouse cucumber disease and insect damage].

The present paper is based on chlorophyll fluorescence spectrum analysis. The wavelength 685 nm was determined as the primary characteristic point for the analysis of healthy or disease and insect damaged leaf by spectrum configuration. Dimensionality reduction of the spectrum was achieved by combining simple intercorrelation bands selection and principal component analysis (PCA). The principal component factor was reduced from 10 to 5 while the spectrum information was kept reaching 99.999%. By comparing and analysing three modeling methods, namely the partial least square regression (PLSR), BP neural network (BP) and least square support vector machine regression (LSSVMR), regarding correlation coefficient of true value and predicted value as evaluation criterion, eventually, LSSVMR was confirmed as the appropriate method for modeling of greenhouse cucumber disease and insect damage chlorophyll fluorescence spectrum analysis.