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The Qinghai-Tibet Plateau (QTP) has the largest amount of permafrost in the low and middle latitudes, making it highly susceptible to the effects of global warming. In particular, the degradation of permafrost can be intensified by anomalous amplified warming. To accurately model the hydrothermal dynamics of permafrost and its future trends, the accumulation of high-precision, long-term data for the soil thermal conductivity (STC) in the active layer is crucial. However, no previous research has systematically investigated the spatio-temporal variation in the STC on the QTP over an extended period. Therefore, this study aims to fill this gap using the XGBoost model to analyze the STC in the permafrost on the QTP from 1980 to 2020. The findings of this study provide some preliminary insights. First, areas with high variation in the STC between the freeze-thaw periods over the 40 years gradually migrated from the western region to the central region. Second, since 2015, STC in more than 90 % of the permafrost region in the thawing period has shown positive growth. While, during the freezing period, the STC also exhibited an increase over most regions of the QTP, though the western region and parts of the northeastern region exhibited a decrease. Third, the spatial center of gravity for the STC during the freezing and thawing periods from 1980 to 2020 shifted. The mean STC was larger in the eastern and northeastern regions during the freezing period and larger in the western region during the thawing period. Fourth, both alpine swamp meadow and alpine meadow exhibited a gradual increase in the STC during the freeze-thaw period from 1980 to 2020. The conclusions and data products from this study are expected to support spatiotemporal modeling of the permafrost on the QTP and assist in the prognosis for its future.
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OBJECTIVE To explore the mechanism of Compound lizard powder reducing cisplatin resistance in gastric cancer by regulating glycolytic activity based on phosphoinositide 3-kinase（PI3K）/protein kinase B（Akt） signaling pathway. METHODS Human gastric cancer MKN45 and MKN45/DDP （cisplatin-resistant） cells were cultured in vitro and intervened with different mass concentrations of cisplatin （0.1， 0.2， 0.4， 0.8， 1.6， 3.2 μg/mL） to detect the survival rate， half inhibitory concentration （IC50） and drug resistance index. MKN45/DDP cells were inoculated subcutaneously in the right anterior axilla of nude mice to prepare a transplanted tumor model of gastric cancer. After successful modeling， they were randomly divided into model group， cisplatin group （0.002 g/kg）， Compound lizard powder group （2.8 g/kg） and combination group （the same dose as each single drug group）， with 8 nude mice in each group. Each administration group was given relevant solution， twice a week （cisplatin， i.p.） or twice a day （Compound lizard powder， i. g.）， for 4 consecutive weeks. During the experiment， the body weight of nude mice was monitored， and tumor volume and inhibitory rate of tumor were calculated. The levels of inflammatory factors （tumor necrosis factor- α， interleukin-6） in tumor tissue， the mRNA and protein expressions of multidrug resistance-associated protein 1 （MRP1）， P-glycoprotein （P-gp）， glucose transporter-1 （GLUT1） and lactate dehydrogenase A （LDHA）， as well as the protein expressions of PI3K， phosphorylated PI3K （p-PI3K）， Akt， phosphorylated Akt （p-Akt）， hexokinase-2 （HK2） and pyruvate kinase M2 （PKM2） were all detected. RESULTS With the intervention of different concentrations of cisplatin， the survival rate of MKN45/DDP-resistant cells was significantly higher than that of MKN45 parent cells （P＜0.05）. IC50 value of MKN45/DDP and MKN45 cells were（1.052 0±0.221 9） and （0.372 1±0.238 0）μg/mL， and the drug resistant index was 2.827. Compared with the model group， cisplatin group， Compound lizard powder group and combination group all had certain inhibitory effects on the tumor growth in nude mice； the inhibitory rates of tumor increased significantly （P＜0.05）； the levels of inflammatory factors， the mRNA and protein expressions of MRP1， P-gp， GLUT1 and LDHA （except for cisplatin group）， the phosphorylation levels of PI3K and Akt protein （except for cisplatin group） as well as the protein expressions of HK2 and PKM2 were decreased significantly， while the combination group was significantly better than the cisplatin group （P＜0.05）. CONCLUSIONS Compound lizard powder may inhibit tumor growth in transplanted tumor model nude mice with gastric cancer-resistant cells by reducing the secretion of tumor-related inflammatory factors， inhibiting the expression of glycolysis， drug resistance-related proteins and genes， inhibiting the activation of the PI3K/Akt signaling pathway， thus having a certain effect of enhancing cisplatin efficacy and reversing drug resistance.
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The onset of primary hepatic carcinoma (PHC) is usually occult, and early symptoms are not obvious. Most patients are at advanced stages of disease at diagnosis, and the prognosis is poor. Paraneoplastic syndrome (PNS) refers to the clinical manifestations indirectly caused by tumor metabolites or abnormal immune reactions that cannot be explained by the primary lesion, local tumor spread or distant metastasis. Hypercholesterolemia, hypercalcemia and hypoglycemia are the most commonly seen clinical presentations of PNS in PHC patients. Adequate understanding of PNS is of great importance in early diagnosis and treatment of PHC. In this review, we summarized the clinical manifestations and prognostic mechanisms of PNS in patients with PHC.
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OBJECTIVE@#To observe the effects of on the expression of β-tubulin Ⅲ and glial fibrillary acidic protein (GFAP) and the proliferation and differentiation of murine neural stem cells (NSCs) .@*METHODS@#An immortalized murine NSC line was divided into model control (MC) group, 10% drug-containing serum group (NLXT group), and 10% Naoluoxintong drug-containing serum with inhibitor Y27632 group (Y-27632 group) with corresponding treatments. The activity of the NSCs was detected after the treatments using MTT assay, and the migration of the cells was observed with Transwell assay. The expressions of β-tubulin Ⅲ, GFAP and MAP-2 proteins in the cells were detected with immunoblotting, and the expressions of DCX, NEUN, and β-tubulin Ⅲ were also detected with immunofluorescence assay.@*RESULTS@#Compared with that in MC group, the number of migrated cells in NLXT group and Y-27632 group increased significantly at 1 day and 3 days after induction ( < 0.05). The survival rate and the number of migrated cells in NLXT group and Y-27632 group increased significantly on day 7 ( < 0.01). Compared with those in MC group, the expressions of β-tubulin Ⅲ, MAP2 and GFAP protein in NLXT group and Y-27632 group were significantly increased on days 3 ( < 0.01) and 7 ( < 0.05). The numbers of β-tubulinⅢ/ GFAP, BrdU/DCX, and BrdU/NEUN labeled cells in the NLXT group and Y-27632 group were significantly greater than those in the MC group.@*CONCLUSIONS@# promotes the proliferation and differentiation of murine NSCs by regulating the expressions of β-tubulinⅢ/GFAP.