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The aim of this study was to explore the effect of circ MTHFD2 on resistance to pemetrexed (MTA) in gastric cancer by regulating the expression of micro ribonucleic acid (miR)-124.Human gastric cancer MGC-803 cells were induced by MTA at an increasing concentration. MGC-803/MTA resistant cell model was successfully established after 5 months. The half-maximal inhibitory concentration (IC50) of MTA on the two kinds of cells was detected via cell counting kit-8 (CCK-8) assay. Differentially expressed circular RNAs (circRNAs) were screened using circRNA microarray analysis. Meanwhile, the target miRNAs of circRNAs were predicted using bioinformatics tool and verified via luciferase reporter assay, respectively. In MGC-803 cells, the effects of overexpression and knockdown of circ MTHFD2 on the expression of miR-124 were detected via quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Finally, the effects of circ MTHFD2 on the protein expressions of FDZ5 and multidrug resistance gene-1 (MDR-1) were detected via Western blotting.MGC-803/MTA resistant cell lines were successfully constructed via persistent drug exposure to MTA at an increasing concentration for 5 months. Compared with parental cells, MGC-803/MTA resistant cells showed significantly enhanced drug resistance. Subsequently, differentially expressed circRNAs were screened using circRNA microarray analysis. A total of 673 circRNAs were screened out based on Fold Change3 and adjusted p-value. The results of qRT-PCR showed that the expression levels of all differentially expressed circRNAs were significantly changed when compared with MGC-803/MTA resistant cells. Compared with MGC-803/MTA resistant cells, the drug resistance of cells increased significantly in circ MTHFD2 overexpression group. However, it markedly decreased in circ MTHFD2 knockdown group. According to the results of bioinformatics and luciferase reporter assay, circ MTHFD2 could target bind to miR-124. In MGC-803/MTA cells, miR-124 could remarkably increase the resistance of MGC-803/MTA cells to MTA. Western blotting results revealed that overexpression of circ MTHFD2 significantly increased the protein expressions of FDZ5 and MDR-1. However, miR-124 mimics reversed the inhibitory effect of circ MTHFD2 on FDZ5 and MDR-1.Circ MTHFD2 directly binds to miR-124 through the molecular sponge effect. This may induce increased protein expression of MDR-1, ultimately enhancing the drug resistance of MGC-803/MTA cells.

Ferroelectric HfZrOx (FE-HZO) negative capacitance (NC) FETs is experimentally demonstrated with physical thickness 1.5 nm, SS = 52 mV/dec, hysteresis free (threshold voltage shift = 0.8 mV), and 0.65 nm CET (capacitance equivalent thickness). The NC-FinFET modeling is validated on standard 14nm FinFET. The transient behavior of gate and drain current response are exhibited with triangular gate voltage sweep. The dynamic NC model with compact equivalent circuit for ultra-thin FE-HZO is established with experimental data validation, and estimates the fast response. A feasible concept of coupling the ultra-thin FE-HZO (1.x nm) with NC as gate stack paves a promising solution for sub-10nm technology node.

Ferroelectric HfZrOx (FE-HZO) FETs is experimentally demonstrated with 0.98nm CET (capacitance equivalent thickness), small hysteresis window VT (threshold voltage) shift < 0.1V, SSfor = 42mV/dec, SSrev = 28mV/dec, and switch-off < 0.2V. The optimum ALD process leads single monolayer SiOx for IL (interfacial layer) and low gate leakage current. The FE-HZO FETs is operated at room temperature and 150K to obtain beyond the physical limitation of Boltzmann tyranny, and the extracted body factors are m = 0.67 and m = 0.89 for Vds = 0.1 and 0.5 V, respectively, to confirm the negative capacitance (NC) effect. There are two proposed strategies to reach hysteresis-free, including FE-HZO/epi-Ge/Si FETs with experimentally VT shift 3mV in hysteresis window, and 3nm-thick FE-HZO resulting hysteresis-free and sub-0.2V switching by numerical simulation.

Capillary electrochromatography (CEC) is a promising micro-separation technique, which combines the high selectivity of HPLC and the high efficiency of HPCE. In comparing to CE with fused silica capillary and CEC with ODS stationary phase, capillary electrophoresis and capillary electrochromatography with ionic coating columns can cause EOF more controllable, and provide an alternative separation mechanism. Therefore, the new CEC and CE modes are in favor of optimizing the separation and broadening the range of samples for analysis. The development of capillary electrophoresis and capillary electrochromatography using ionic coating column is reviewed with 48 references.

Objective. To observe the transition time of soleus I (TnI) isoforms and to elucidate the relationship between soleus TnI transition and atrophy; and to analyze the time course between testis atrophy and soleus atrophy. Method. Eight groups of male rats were suspended for 3, 4, 5, 7, 14, 21, 28 and 42 d, respectively. Besides, three groups of female rats were suspended for 3, 4 and 5 d respectively. Wet and relative weights (wet weight/body weight) of testis and soleus were measured. The expression of TnI was observed by Western blot. Result. The relative weight of soleus of tail-suspended male rats decreased significantly after 4 d of suspension as compared with control. The degree of rats soleus atrophy in the first 14 d of suspension was greater than that after 14 d. The relative weight of testis showed the same change as that of soleus. There was no significant change in the relative weight of soleus in 4 d of tail-suspended female rats. The significant decrease in the relative weight of tail-suspended female rats began on the 5th day. The Western blot showed that the transition from slow skeletal TnI (ssTnI) to fast skeletal TnI (fsTnI) in the soleus occurred in 14 d of tail-suspension. Conclusion. The overt atrophy of tail-suspended male rats occurs on the 4th day. The soleus TnI transition from ssTnI to fsTnI is on the 14th day. It is suggested that the TnI is not the sensitive protein to gravity. The overt atrophy of female tail-suspended rats occurs at the 5th day. This indicated that the decrease in testosterone level may accelerate the atrophy of the soleus.

The p8 gene is barely expressed in the normal pancreas, but is overexpressed in acute pancreatitis. To elucidate the dynamic expression of p8 mRNA and its significance in the course of chronic pancreatitis, we investigated the p8 expression in spontaneous chronic pancreatitis in the WBN/Kob rat as well as in humans and arginine-treated rat pancreatic acinar AR4-2J cells. p8 mRNA was significantly increased at 12 weeks when chronic pancreatitis first appeared in the WBN/Kob rats. p8 was immunolocalized in the acinar cell nuclei. Acinar cell apoptosis was significantly increased at 12 and 20 weeks in the WBN/Kob rats. In AR4-2J cells, p8 mRNA was significantly induced at 4 hr after arginine addition. Apoptosis of AR4-2J cells was not increased during the strong expression of p8 mRNA. These results suggest that p8 is induced in the acinar cells during chronic pancreatitis as the self-defence mechanism against proapoptotic insults.

A recently identified gene, p8, has cell growth-promoting activity and is strongly induced in acute pancreatitis. In this study, we detected p8 and single-stranded DNA (ssDNA) for apoptosis by immunohistochemistry in human pancreatic cancer. The p8 was overexpressed (30% per 1000 cancer cells) in 26 of 44 (59%) pancreatic cancers, and apoptosis (ssDNA-positive cells10% per 1000 cancer cells) was recognized in 18 of 44 (41%) pancreatic cancers. There was a significant inverse correlation between the p8 overexpression and apoptosis (P0.05). Moreover, the expression pattern of high p8 and low ssDNA was seen significantly more often in lower age (65 years), in moderately or poorly differentiated cancers, and in node-positive cases (P0.05). The p8 expression and apoptosis were not significantly correlated with survival. These results suggest that p8 overexpression is involved in antiapoptotic activity and the biological characteristics of pancreatic cancer.

The Fas/Fas ligand (FasL) system is suggested to be correlated to the onset of inflammation and apoptosis in various diseases. However, whether Fas and FasL are expressed in chronic pancreatitis is unknown. The aim of this study was to examine the expression of the Fas/FasL system and to analyze its correlation with apoptosis in a spontaneous chronic pancreatitis model (the WBN/Kob rat). Four-week-old male WBN/Kob rats were fed a special pellet diet (MB-3). Different groups of rats were killed every four weeks, and pancreata were histopathologically examined. Fas and FasL mRNAs in the pancreas were detected with a reverse transcription-polymerase chain reaction method. The cellular localization of Fas and FasL mRNA and protein was determined with in situ hybridization (ISH) and immunohistochemistry (IHC). Apoptosis was detected with a terminal deoxynucleotidyltransferase-mediated method. Fas and FasL mRNA were expressed when the pancreas was still pathologically normal, and showed a biphasic peak at 12 and 20 weeks. ISH and IHC confirmed that Fas and FasL are expressed in the cytoplasm of acinar cells, ductal cells, and lymphocytes. An apoptotic index in acinar cells correlated to the expression of Fas and FasL mRNAs. These results suggest that the expression of the Fas/FasL system is involved in acinar cell apoptosis and the onset and progression of chronic pancreatitis in the WBN/Kob rat.

The p8 gene is a recently identified gene with mitogenic activity. p8 expression is induced in acute pancreatitis, pancreatic development, and regeneration. However, the expression of p8 in pancreatic cancer is not reported. We investigated p8 expression in 72 human pancreatic tissues, including 38 pancreatic cancers (PCs), by immunohistochemistry. p8 was overexpressed (positive cells25% in 1,000 cells) in 71% (27 of 38) of PCs, but in only 17% (3 of 18) of chronic pancreatitis cases. There was no overexpression in mucinous cystadenoma or in normal pancreas. The p8 overexpression rate in PC was significantly higher than that in other conditions (P0.05). Reverse transcription-PCR analysis confirmed p8 mRNA overexpression (tumor/nontumor ratio2) in 75% (3 of 4) of PCs. p8 was overexpressed also in human pancreatic cancer cell lines (MIA PaCa-2 and PANC-1). These results suggest that p8 is involved in the development of pancreatic cancer, reflecting its mitogenic activity.

In an attempt to obtain evidence of the beneficial effects of TJ-10, we investigated the gene expression of PAP, an acute phase protein specific for pancreatitis in rat spontaneous chronic pancreatitis.Four-wk-old male WBN/Kob rats were fed with MB-3 pellet diet containing herbal medicine. There were two administration groups for each drug: the prophylactic group administered from 4-12 wk, and the therapeutic group administered from 12-20 wk. Untreated control rats were fed with MB-3 alone. Histopathologic changes and PAP gene expressions were analyzed at 12 and 20 wk.In the prophylactic group, TJ-10-treated WBN/Kob rats showed no evidence of pancreatitis, and there was the amelioration of pancreatitis in the pancreata of the rats treated with other herbal medicines except TJ-24 at 12 wk. PAP mRNA was not expressed in the TJ-10-treated rats, and PAP gene expression was suppressed in rats treated with other drugs except TJ-107. In the therapeutic group, the amelioration of pancreatitis was seen only in TJ-10-treated rats, but PAP gene expression was significantly suppressed in the rats treated with all herbal medicines tested, compared with that in untreated control rats.An herbal medicine Saiko-keishi-to (TJ-10) delayed the onset of chronic pancreatitis in the WBN/Kob rat, and suppressed the pancreatitis-associated protein (PAP) gene expression more significantly than other herbal medicines.

Transforming growth factor-beta1 (TGF-beta1) is suggested to be a mediator of fibrosis in chronic pancreatitis, but the serial change of TGF-beta1 expression in the onset and progression of chronic pancreatitis is still unclear. We investigated the TGF-beta1 expression in the spontaneous chronic pancreatitis model. Four-week-old male WBN/Kob rats were fed with special pellet diet (MB-3) for 20 weeks. TGF-beta1 mRNA in the pancreas was detected by reverse transcription-polymerase chain reaction assay from four weeks, and its expression peaked at 12 weeks when the pancreatic fibrosis first appeared. The localizations of TGF-beta1 mRNA and protein were confirmed in the cytoplasm of pancreatic acinar and ductal cells by in situ hybridization and immunohistochemistry, respectively. Although fibronectin expression peaked at 12 weeks and correlated with that of TGF-beta1, its elevated expression tended to be prolonged. Pancreatic fibrosis peaked at 16 weeks after the peak of TGF-beta1 expression. These results suggest that TGF-beta1 expression may be a trigger of the fibrotic process of chronic pancreatitis in the WBN/Kob rat.

From May 1985 to December 1991, high frequency electrical knife (HFEK) through fibrobronchoscope was used to treat the large airway obstruction by tracheal cancers in 11 patients (cystic adenoid carcinoma: 8 squamous cell carcinoma: 2 and undifferentiated small cell carcinoma: 1). Most of the tracheal cancer patients were inoperable because of extensive lesions or poor lung function. Olympus BF B3R or BF 10 Type Fibrobronchoscope, Olympus UES or Olympus PSD-10 high frequent electricity producer with a home-made electrical knife were applied. After 53 times of HFEK treatment of tracheal cancer, all patients showed remarkable improvement in lung function and exertional dyspnea.HFEK is valuable in relieving dyspnea in patients with large airway obstruction with tracheal cancer. After endoscopic cautery to release the obstruction, it is necessary to use radiotherapy and chemotherapy for the patients to get better results.