Does high-speed rail improve China's urban environmental efficiency? Empirical evidence from a quasi-natural experiment.

Whether high-speed rail (HSR) can promote the coordination between the economy and environment is a critical issue that needs to be investigated. We used balanced panel data of 281 prefecture-level or above cities in China from 2005 to 2017 to consider the opening of HSR as a quasi-natural experiment. We integrated the difference-in-differences (DID) model, the spatial difference-in-differences (SDID) model, and social network analysis (SNA) to empirically investigate the impact of HSR on urban environmental efficiency (UEE). The results showed that HSR significantly improved UEE by 4.6% annually during the study period, although the effect of HSR on UEE exhibited a time lag and varied dramatically in different cities. An analysis of the mechanism showed that the effect of technological innovation and the structural effect brought by the opening of HSR were the main contributors to the improved UEE. Further analysis showed that HSR service centrality also significantly improved UEE and HSR opening and HSR service centrality both had positive spatial spillover effects on the UEE of neighboring cities. Several policy implications are proposed accordingly to make full use of the advantages of HSR to improve UEE for China.

Differentiation-inducing activity of hydroxycamptothecin on cancer stem-like cells derived from hepatocellular carcinoma.

BACKGROUND: Hydroxycamptothecin (HCPT) is an anti-tumor agent that can induce differentiation in human cancer cells. Recent evidence indicates that side population (SP) cells possess characteristics of stem-like cells, and may be capable of initiating tumor growth. AIMS: The present study investigated the differentiation of cancer stem-like cells derived from hepatocellular carcinoma. METHODS AND RESULTS: Flow cytometry was used to isolated SP cells from HCC cell line (MHCC97 cells). These SP cells exhibit several stem-like cell characteristics that are distinct from the main population (MP) cells in vitro. After 3 days of induction with a low concentration of HCPT, the SP cells lost their capacity to proliferate and invade, and their tumorigenicity declined. Based on real-time quantitative RT-PCR, we also found that the expression of hepatocyte-specific markers such as α-fetoprotein, albumin, hepatocyte nuclear factor-4 and miR-122 gradually changed during the differentiation of SP cells. CONCLUSIONS: Our data suggest that a low concentration of HCPT can induce hepatocyte-specific differentiation of cancer stem-like cells from MHCC97 cells, offering a possible therapeutic strategy for the treatment of human malignancies.

Relationship between FDI, fiscal expenditure and green total-factor productivity in China: From the perspective of spatial spillover.

Deeply investigating the relationship between foreign direct investment (FDI), fiscal expenditure and green total-factor productivity (GTFP) is beneficial to formulating effective policies to promote the high-quality development in China. Based on theoretical mechanism analysis, with panel data of China's mainland 30 provinces during 2003-2017, this paper utilizes spatial econometric model to empirically explore the effects of FDI, fiscal expenditure and their interaction item on the growth of GTFP in China. The results show that FDI significantly promote the growth of the local and its neighboring GTFP, and both fiscal expenditure and the interaction between FDI and fiscal expenditure exert significantly negative effects on the growth of GTFP in the local and its neighboring regions. A series of robustness checks and the endogeneity test can ensure the reliability of these results. In addition, great heterogeneity can be found across China's different regions in the relationship between FDI, fiscal expenditure and GTFP. The conclusions suggest that it is necessary to give fully play to the synergy between FDI and fiscal expenditure and formulate regionally targeted policies to improve GTFP and promote high-quality development in China.

[Significance of glypican-3 mRNA expression in hepatocellular carcinoma tissues and peripheral blood cells].

OBJECTIVE: To investigate the expressions of glypican-3 (GPC3) mRNA in hepatocellular carcinoma (HCC) tissues and peripheral blood cells (PBCs), and to determine the values of GPC3 mRNA in the diagnosis of HCC and HCC micrometastasis. METHODS: Using semi-quantitative and nested reverse transcription polymerase chain reactions (RT-PCR), we detected the expressions of AFP and GPC3 genes in the tissues of 41 HCC, 41 paracancer and 52 non-HCC liver samples (41 far from HCC tissues and 11 normal liver tissues), and in the PBCs of 67 specimens from subjects. RESULTS: The semi-quantitative RT-PCR displayed GPC3 mRNA was expressed in all samples of tissues and PBCs, and the relative intensities of its expressions in HCC, paracancer, non-HCC liver tissues were 78.9 +/- 35.5, 30.6 +/- 21.6, 23.8 +/- 15.5 respectively. The AFP mRNA expression values were 61.2 +/- 32.6, 31.5 +/- 23.6, and 21.2 +/- 15.9 respectively. The expression of each gene in HCC differed significantly from those in other two kinds of tissue samples (P < 0.01). The expressions of GPC3 mRNA and AFP mRNA, accounting for 80.5% and 63.4% in all the HCC tissues, were higher than their respective peak values in the tissues of non-HCC liver (+1.96s), but the expressions of at least one of the two genes was elevated in 92.7% of all the HCC tissues. There was a significant difference between combined detection of two genes and single AFP mRNA detection in HCC tissues (P < 0.01). Clinicopathologically, AFP mRNA was related with the grade of HCC and serum AFP, while GPC3 mRNA was related with not only the grade of HCC but also the invasion of HCC. The relative intensities of GPC3 mRNA expressions in PBCs of 67 specimens was 15.9 +/- 9.0, and GPC3 mRNA expressed in three kinds of tissue samples were all stronger than its counterparts in PBCs (P < 0.01). The GPC3 mRNA expression values in PBCs of the HCC group and the non-HCC group were respectively 16.1 +/- 8.3, 15.6 +/- 10.2, there was no significant difference between the two groups. Of the HCC metastasis group and the HCC non-metastasis group, the respective GPC3 mRNA expression values in PBCs were 16.0 +/- 9.0 and 16.3 +/- 7.7, there was also no significant difference between the two groups. The nested RT-PCR showed that the positive rates of AFP mRNA expressions in PBCs from the HCC group and the non-HCC group were 56.1% and 23.1%, and the difference between the two groups was significant (P = 0.011). The positive rates of AFP mRNA expressions in PBCs from the HCC metastasis group and the HCC non-metastasis group were 80.9% and 30.0%, and there was also a significant difference between the two groups (P = 0.002). CONCLUSIONS: Although GPC3 mRNA is expressed broadly, it still may serve as a potential tissue biomarker in the diagnosis of HCC. Detecting the expression of the two genes in the tissues will improve the screening and diagnosis of HCC. GPC3 is prevalently transcribed in the PBCs, but we have not found any relationship between the GPC3 expression in PBCs and the metastasis or recurrence of hepatocellular carcinoma, thus we can not identify HCC micrometastasis with GPC3 mRNA.

Hepatocellular carcinoma metastasis to the gingival soft tissues: A case report and review of the literature.

Metastases to the gingival soft tissues are rare in hepatocellular carcinoma (HCC). To the best of our knowledge, only 13 cases have been reported in English literature to date. The present study described the case of a 43-year-old Chinese man who was admitted to Tangdu Hospital (Xi'an, China) due to the presence of a gingival tumor that was initially diagnosed as granulation tissue by a dental surgeon. Examination of the patient's medical history revealed that a solid mass, measuring 1.5 cm in diameter, was identified in the right lobe of the liver 2 years prior to presentation at the current hospital; however, no biopsy was performed. Thus, the tumor was resected and histological examination resulted in an initial diagnosis of atypical squamous cell carcinoma. However, the histopathological characteristics, immunohistochemical features and serum α-fetoprotein expression levels supported a diagnosis of metastatic HCC. In conclusion, the present case study highlights the difficulties in diagnosing metastatic HCC without a history of primary HCC, and the importance of excluding a diagnosis of metastatic tumor when a lesion is identified in the gingival. Furthermore, it was determined that a final diagnosis of gingival metastasis of HCC predominantly depends on pathological characteristics and immunohistochemical features.

Therapeutic effects of DCDDP, a calcium channel blocker, on chronic pulmonary hypertension in rat.

To explore the effect of dimethyl 4-(2-chlorophenyl)-1,4-dihydro-2,6-dimethyl-3,5-pyridinedicarboxylate (DCDDP) on pulmonary hypertension (PH) induced by monocrotaline (MCT), the parameters of pulmonary hemodynamics, the contents of endothelin-like immunoreactivity, nitric oxide (NO), malondialdehyde, and superoxide dismutase in plasma and pulmonary homogenate were measured. DCDDP was administered in 5, 50, and 500 microg x kg(-1) x day(-1) ip doses, once a day for 28 days. The antiserotonin effect of DCDDP was investigated by using immunohistochemistry, image analysis, and cell culture technique. The results showed that pulmonary arterial pressure was significantly dropped and pulmonary resistance was decreased in DCDDP groups, compared with the MCT group. DCDDP had no influence on endothelin-like immunoreactivity levels in plasma and pulmonary homogenate but reduced the contents of NO, superoxide dismutase, and malondialdehyde in pulmonary homogenate enhanced by MCT. DCDDP also significantly inhibited the increase in numbers of 5-hydroxytryptamine (5-HT) and 5-HT receptor-positive cells in pulmonary tissue of PH rats induced by MCT. The proliferation and contraction of pulmonary arterial smooth muscle cells and the increase in concentration of free Ca(2+) in them evoked by 5-HT were inhibited significantly by DCDDP. The results suggest that DCDDP reduces the production of free radicals and content of 5-HT and 5-HT receptor and the increase in NO in pulmonary tissue, which underlies the mechanisms of DCDDP against MCT-induced PH.

Characterization of a stem-like population in hepatocellular carcinoma MHCC97 cells.

A small stem-like subpopulation was isolated from human hepatocellular carcinoma (HCC) MHCC97 cells, characterized by their high efflux ability of the Hoechst 33342 dye. These side population (SP) cells were able to generate a heterogeneous mixture of SP and main population (MP) cells, while the MP cells rarely generated SP cells. Cell cycle analysis also revealed that more SP cells were in the G0 phase. They express higher levels of BCRP1, AFP and CK19 than MP cells. SP cells showed significantly higher viability than MP cells following treatment with doxorubicin or methotrexate. Actin polymerization and migration assays indicate that SP cells have a higher migration capacity and in vivo tumorigenicity of these cells is also higher. Collectively, we conclude that the SP is an enriched source of stem-like cells and may be an effective target for therapy and a useful tool to investigate the HCC tumorigenic and metastatic process.

[Effects and mechanism of decorin on the proliferation of HuH7 hepatoma carcinoma cells in vitro].

AIM: To investigate the effects and mechanism of decorin( DCN) on the proliferation of HuH7 hepatoma carcinoma cell line in vitro. METHODS: Hepatoma carcinoma cells was cultured with DCN in different concentration (0, 25, 50, 75, 100, 125, 150, 200 microg/L) for different time(12, 24, 48, 72 h and 2 weeks). Cell activities were studied by MTT and clone test. The changes of cell cycle and apoptosis were analyzed by Flow cytometry. RESULTS: The proliferation of HuH7 cells could be inhibited by DCN in vitro and the inhibition effect was the time and dose dependent relationship. DCN could block cell cycle at G(1); phase. Apoptosis of hepatocarcinoma cells could be efficiently induced by DCN in a time/dose-dependent manner. CONCLUSION: DCN may be a negative regulatory protein inhibiting hepatoma carcinoma cell proliferation through inhibiting cell cycle and inducing apoptosis of cell in vitro.

[The killing effect and bystander effect of linamarase/linamarin suicide gene system on human hepatocellular carcinoma cell line HepG2 in vitro].

AIM: To investigate the killing effect of linamarase/linamarin (lis/lin) system on hepatocellular carcinoma cell line HepG2 in vitro. METHODS: A cDNA library was built from RNA of cassava by RT-PCR, then the linamarase gene was amplified from it by PCR and cloned into the eukaryotic expression vector plasmid pEGFP-N1, which made up the recombinant plasmid pEGFP-N1-lis. The human HCC cells HepG2 were transfected with the recombinant plasmid mediated by electroporation and screened by G418 to yield the positive clone which was termed HepG2/lis. The expression of lis was confirmed by fluorescent staining, RT-PCR and Western blot. The killing effect and bystander effect of linamarin with different concentrations on HepG2 was detected by MTT. RESULTS: RT-PCR confirmed the expression of lis gene in HepG2 and Western blot analysis confirmed existence of lis-EGFP fusion protein in HepG2. Linamarin in low concentration had shown notable cytotoxic effect on HepG2/lis. When HepG2/lis cells were mixed with parental HepG2 cells at a ratio of 10:90 and cultivated in 500 mg/L lin medium, significant bystander effect was observed in vitro. CONCLUSION: The linamarase/linamarin suicide gene system has strong killing effect and bystander effect on HCCs with the concentration of 500 mg/L lin.

[Immune tolerance induced by IL-10 and methylprednisolone modified dendritic cells in vitro].

AIM: To study the effect on induction of allograft immune tolerance by IL-10 and methylprednisolone (Medron) modified dendritic cells(DC) of donor in murine allogenetic skin transplantation model. METHODS: The recipient BALB/c mice were divided into 11 groups.Except group A, each group had been injected with corresponding donor DC through vena caudalis, and transplanted full-thickness skin through back to back from donor C57BL/6 three days later. Corresponding doses were: A: injected NS, blank control; B: injected non-modified donor DC; C1: 10 microg/L IL-10 group; C2: 30 microg/L IL-10 group; D1: 10 mg/L Medron group; D2: 20 mg/L Medron group; E1-E4: 10 microg/L IL-10+10 mg/L Medron group, 10 microg/L IL-10+20 mg/L Medron group, 30 microg/L IL-10+10 mg/L Medron group and 30 microg/L IL-10+20 mg/L Medron group. F group was skin transplantation between two BALB/c mice. Skin transplantation was performed and the survival time of skin allografts was observed. RESULTS: Among all the groups, the graft of E3 group(30 microg/L IL-10 mg/L Medron) survived for the longest time. Statistical analysis showed that there was interaction between IL-10 and Medron (P<0.05). CONCLUSION: The pretreatment with donor DC treated by IL-10 and Medron can prolong the survival time of murine skin allografts after transplantation and induce immune tolerance successfully.

[Effect of granulocyte colony-stimulating factor on the ratio of peripheral blood dendritic cell subsets].

AIM: To clarify the effect of granulocyte colony-stimulating factor (G-CSF) on the radio of two peripheral blood dendritic cell(DC) subsets in-vivo. METHODS: Various doses (0, 5, 10 and 15 microg) of G-CSF were subcutaneosly injected respectively into BALB/c mice, once each day, for 6 days running. Six days later, DCs were separated from peripheral blood. Then the flow cytometry was used to detect the radio of DC1 and DC2 (CD11c(+) CD8a(-) and CD11c(+) CD8a(+)), and to calculate their absolute numbers. RESULTS: After stimulation with varying doses of G-CSF for 6 days, the absolute number of DC2s increased from 9.6x10(6)/L to 55.1x10(6)/L (P<0.01), while that of DC1s had no notably variation, so the ratio of DC1 and DC2 decreases from 4.2+/-1.1 to 0.7+/-0.3 (P<0.01). CONCLUSION: G-CSF can increase the absolute number of peripheral blood DC2s, but has no influence on peripheral blood DC1 number, thus inversing the ratio of DC1/DC2 in-vivo.