In vitro studies can help reveal the biochemical pathways underlying the origin of volatile indicators of numerous diseases. The key objective of this study is to identify the potential biomarkers of gastric cancer. For this purpose, the volatilomic signatures of two human gastric cancer cell lines, AGS (human gastric adenocarcinoma) and SNU-1 (human gastric carcinoma), and one normal gastric mucosa cell line (GES-1) were investigated. More specifically, gas chromatography mass spectrometry has been applied to pinpoint changes in cell metabolism triggered by cancer. In total, ten volatiles were found to be metabolized, and thirty-five were produced by cells under study. The volatiles consumed were mainly six aldehydes and two heterocyclics, whereas the volatiles released embraced twelve ketones, eight alcohols, six hydrocarbons, three esters, three ethers, and three aromatic compounds. The SNU-1 cell line was found to have significantly altered metabolism in comparison to normal GES-1 cells. This was manifested by the decreased production of alcohols and ketones and the upregulated emission of esters. The AGS cells exhibited the increased production of methyl ketones containing an odd number of carbons, namely 2-tridecanone, 2-pentadecanone, and 2-heptadecanone. This study provides evidence that the cancer state modifies the volatilome of human cells. 相似文献
HIF means hypoxia-inducible factor gene family, and it could regulate various biological processes, including tumor development. In 2021, the FDA approved the new drug Welireg for targeting HIF-2a, and it is mainly used to treat von Hippel-Lindau syndrome, which demonstrated its good prospects in tumor therapy. As the fourth deadliest cancer worldwide, gastric cancer endangers the health of people all across the world. Currently, there are various treatment methods for patients with gastric cancer, but the five-year survival rate of patients with advanced gastric cancer is still not high. Therefore, here we reviewed the regulatory role and target role of HIF in gastric cancer, and provided some references for the treatment of gastric cancer. 相似文献
The kinetics of the adsorption of human gastric lipase (HGL) and human pancreatic lipase (HPL) were studied by recording the changes in the surface pressure with time in the absence and presence of an egg phosphatidylcholine (PC) monomolecular film spread at the air/water interface. In the presence of PC film, the tensioactivtty of HGL increased considerably compared with its behaviour at the air/water interface, whereas HPL exhibited a comparable degree of tensioactivity whether or not a phospholipid monolayer was present at the interface. This difference in surface behaviour is consistent with the higher penetration capacity attributed to HGL. Procolipase considerably increased both the initial adsorption rate and the final surface pressure reached by HPL compared with its adsorption without colipase.
The kinetics of the hydrolysis of 1,2-didecanoyl-sn-glycerol (dicaprin) monolayers by HGL and HPL were measured using a “zero-order” trough. The large differences between the calculated characteristic adsorption times and the measured lag times indicate that the partition of the lipase molecules between the subsurface and the interface was probably limited by an energy barrier. The amplitude of this energy barrier can be partly attributed to the drastic conformational change in the enzyme, associated with the interfacial activation.
The area per dicaprin molecule (56 Å2) corresponding to the maximal activity of HPL was compared with the dimension of the hydrophobic cleft surrounding the serine (Ser 152) of the catalytic triad of HPL, as recently demonstrated by H. Van Tilbeurgh and co-workers (Nature, 359 (1992) 159; 362 (1993) 814) in their studies on the “open” and “closed” forms of the respective three-dimensional crystalline structures. The catalytic triad was not accessible to a sphere 8.4 Å in diameter, mimicking the van der Waals envelope of the dicaprin molecule, due to the steric hindrance of the side chains of aromatic and cyclic residues F 215, F 77, Y 114 and H 263. It can be concluded that the substrate molecule must also undergo some conformational changes at the contact of the enzyme to be accommodated in the active site. 相似文献
An analytical method was developed for determination of valsartan in commercial drug and sewage sludge samples by HPLC–UV using a single wavelength (250 nm). The effect of different environmental storage conditions on the stability of valsartan was examined for a period of 85 days, after which no degradation was observed. The post oral administration stability of the valsartan was also investigated by testing valsartan under simulated gastric conditions. Results obtained showed that the structure of valsartan was conserved over 3.5-h period. The calibration plot of the study was linear over a wide concentration range with a correlation coefficient of 0.9999. The limit of detection and limit of quantitation were found to be 0.014 and 0.046 µ g mL?1, respectively. The percentage recovery of valsartan from sewage sludge was found to be 99.8%. 相似文献
The 6‐O‐ sulfate ester of morphine (M6S) has previously been shown to be an analgesic with greater potency and fewer side effects than morphine. However, being a sulfate ester derivative of morphine, the question exists as to whether this compound is stable in biological fluids and tissues with regard to pH‐ and esterase‐mediated degradation. To date, no studies have focused on the stability profile of M6S across the physiologically relevant pH range of 1.2–7.4. In addition, the stability of M6S is not known in rat plasma and rat brain homogenate, or in simulated rat gastric and intestinal fluids. This study determines the stability profile of M6S (utilized as the sodium salt) and demonstrates that M6S is highly stable and resilient to either enzymatic‐ or pH‐dependent hydrolysis in vitro . 相似文献