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1.
Sci Prog ; 106(1): 368504231152742, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36751053

RESUMO

A growing consensus worldwide has indicated the need to protect the ecological environment and achieve sustainable development. Ensuring ecological protection and high-quality development of the Yellow River basin have become China's major national strategy. We reviewed extant literature, summarised government reports and guidance documents on the Yellow River basin, and proposed introducing a strong sustainable development theory into the study of total factor productivity (TFP). The spatial-temporal evolution and influencing factors of urban ecological TFP in the Yellow River basin are of great practical significance. We proposed a new ecological TFP indicator: the modified input-oriented Luenberger productivity indicator (MIL). Using panel data from 78 cities in the Yellow River basin during 2003-2019, we measured the urban ecological TFP. We adopted the geographic information system tool and kernel density estimation to analyse the temporal and spatial evolution of the indicator, as well as its spatial effects and influencing factors, using the global Moran's I index and dynamic spatial Durbin model (SDM). Our results show that, during the sample period, our indicator increased in cities in the region with an average annual growth rate of 0.627%, driven by technological progress. The average annual growth rate in urban areas showed a decreasing distribution of 'downstream-midstream-upstream'. Fiscal decentralisation (FD), industrial structure (IND), financial development (FIN), urbanisation level (URB) and research and development (RD) investment improved growth rates in this and the adjacent regions through direct and indirect effects. However, environmental regulation (ER), opening level (OPEN) of cities and population density (POP) were obstacles to TFP growth.

2.
Magn Reson Chem ; 56(3): 190-195, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29172023

RESUMO

The local distortions and electron paramagnetic resonance parameters for Cu2+ in the mixed alkali borate glasses xNa2 O-(30-x)K2 O-70B2 O3 (5 ≤ x ≤ 25 mol%) are theoretically studied with distinct modifier Na2 O compositions x. Owing to the Jahn-Teller effect, the octahedral [CuO6 ]10- clusters show significant tetragonal elongation ratios p ~19% along the C4 axis. With the increase of composition x, the cubic field parameter Dq and the orbital reduction factor k exhibit linearly and quasi-linearly decreasing tendencies, respectively, whereas the relative tetragonal elongation ratio p has quasi-linearly increasing rule with some fluctuations, leading to the minima of g factors at x = 10 mol%. The composition dependences of the optical spectra and the electron paramagnetic resonance parameters are suitably reproduced by the linear or quasi-linear relationships of the relevant quantities (i.e., Dq, k, and p) with x. The above composition dependences are analyzed from mixed alkali effect, which brings forward the modifications of the local crystal-fields and the electronic cloud distribution around Cu2+ with the variation of the composition of Na2 O.

3.
Biomed Rep ; 2(3): 388-391, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24748980

RESUMO

This study was conducted to evaluate the sedative effects of Arachis hypogaea L. stem and leaf extract (AHSLE) and determine its effect pathways through γ-aminobutyric acid (GABA)-gated channels on male Sprague-Dawley rats treated with pentobarbital. AHSLE was obtained from 98°C water (3 h, extracted twice). AHSLE and flumazenil (a GABA type A receptor antagonist) were administered to the rats orally, whereas pentobarbital sodium and muscimol (a GABA type A receptor agonist) were administered intraperitoneally (i.p.). The results demonstrated that AHSLE decreased sleep latency and increased sleep time in pentobarbital-treated rats (50 mg/kg, i.p.). The coadministration of AHSLE and muscimol (0.05 mg/kg) significantly increased sleep time and reduced sleep latency in pentobarbital-treated rats and these actions were significantly antagonized by flumazenil at a dose of 3.5 mg/kg. These results indicated that AHSLE improved the sleep behavior in pentobarbital-treated rats, possibly through GABA-gated channel-related mechanisms.

4.
World J Gastroenterol ; 18(4): 356-67, 2012 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-22294842

RESUMO

AIM: To further investigate the important role of store-operated calcium channels (SOCs) in rat hepatocytes and to explore the effects of SOC blockers on hepatic ischemia-reperfusion injury (HIRI). METHODS: Using freshly isolated hepatocytes from a rat model of HIRI (and controls), we measured cytosolic free Ca(2+) concentration (by calcium imaging), net Ca(2+) fluxes (by a non-invasive micro-test technique), the SOC current (I(SOC); by whole-cell patch-clamp recording), and taurocholate secretion [by high-performance liquid chromatography and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays]. RESULTS: Ca(2+) oscillations and net Ca(2+) fluxes mediated by Ca(2+) entry via SOCs were observed in rat hepatocytes. I(SOC) was significantly higher in HIRI groups than in controls (57.0 ± 7.5 pA vs 31.6 ± 2.7 pA, P < 0.05) and was inhibited by La(3+). Taurocholate secretion by hepatocytes into culture supernatant was distinctly lower in HIRI hepatocytes than in controls, an effect reversed by SOC blockers. CONCLUSION: SOCs are pivotal in HIRI. SOC blockers protected against HIRI and assisted the recovery of secretory function in hepatocytes. Thus, they are likely to become a novel class of effective drugs for prevention or therapy of HIRI patients in the future.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio/metabolismo , Hepatócitos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/metabolismo , Sinalização do Cálcio/fisiologia , Células Cultivadas , Colagogos e Coleréticos/metabolismo , Hepatócitos/citologia , Hepatócitos/metabolismo , Fígado/citologia , Fígado/patologia , Masculino , Norepinefrina/farmacologia , Técnicas de Patch-Clamp , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia , Ácido Taurocólico/metabolismo
5.
World J Gastroenterol ; 17(13): 1685-9, 2011 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-21483627

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common malignancies, ranking the sixth in the world, with 55% of cases occurring in China. Usually, patients with HCC did not present until the late stage of the disease, thus limiting their therapeutic options. Although surgical resection is a potentially curative modality for HCC, most patients with intermediate-advanced HCC are not suitable candidates. The current therapeutic modalities for intermediate-advanced HCC include: (1) surgical procedures, such as radical resection, palliative resection, intraoperative radiofrequency ablation or cryosurgical ablation, intraoperative hepatic artery and portal vein chemotherapeutic pump placement, two-stage hepatectomy and liver transplantation; (2) interventional treatment, such as transcatheter arterial chemoembolization, portal vein embolization and image-guided locoregional therapies; and (3) molecularly targeted therapies. So far, how to choose the therapeutic modalities remains controversial. Surgeons are faced with the challenge of providing the most appropriate treatment for patients with intermediate-advanced HCC. This review focuses on the optional therapeutic modalities for intermediate-advanced HCC.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Carcinoma Hepatocelular/patologia , Guias como Assunto , Humanos , Neoplasias Hepáticas/patologia
6.
Chin Med J (Engl) ; 123(19): 2714-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21034658

RESUMO

BACKGROUND: Vaccinium uliginosum L. is a type of blueberry found in the Chinese Changbai Mountains. We extracted Vaccinium uliginosum Anthocyanins (A(V.uli)) to investigate its bioactivity on suppressing cancer cells. METHODS: A(V.uli) was extracted under different conditions of temperature (10°C - 35°C), pH 1.0 - 3.0, and diatomaceous earth (1.0 g - 3.0 g), followed by a HPLC analysis for the determination of the ingredients. Its anticancer bioactivities on human colon and colorectal cancer cells (DLD-1 and COLO205) were compared with those on Lonicera caerulea Anthocyanins (A(L.cae)) and Vaccinium myrtillus Anthocyanins (A(V.myr)), using cell viability assays, DNA electrophoresis and nuclear morphology assays. RESULTS: The optimum process of A(V.uli) extraction involved conditions of temperature 20°C, pH 2.0, and diatomaceous earth 1.0 g/50 g of fruit weight. A(V.uli) contained 5 main components: delphinidin (40.70 ± 1.72)%, cyanidin (3.40 ± 0.68)%, petunidin (17.70 ± 0.54)%, peonidin (2.90 ± 0.63)% and malvidin (35.50 ± 1.11)%. The malvidin percentage was significantly higher (P < 0.05) than it in A(V.myr). A(V.uli) complied with a dose-dependent repression of cancer cell proliferation with an IC(50) (50% inhibitory concentration) value of 50 µg/ml, and showed greater anticancer efficiency than A(L.cae) and A(V.myr) under the same cell treatment conditions. These observations were further supported by the results of nuclear assays. CONCLUSIONS: The extraction protocol and conditions we used were effective for anthocyanin extraction. A(V.uli) could be a feasible practical research tool and a promising therapeutic source to suppress human colon or colorectal cancers.


Assuntos
Antocianinas/uso terapêutico , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Mirtilos Azuis (Planta)/química , Extratos Vegetais/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Fragmentação do DNA/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio
7.
Amino Acids ; 39(1): 195-204, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19997763

RESUMO

STIM1, Orai1 and TRPC1 are all reported to be important for store-operated Ca(2+) entry (SOCE) in diverse cells. However, there is no evidence for the functional interaction of the three proteins in SOCE in human liver cells. The objective of this study is to determine whether they are involved in SOCE in normal human liver cells. Liposomal transfection method was used to increase expression levels of the three proteins in HL-7702 cells, a normal human liver cell line. Western blot and single cell RT-PCR were applied to evaluate transfection effectiveness. Changes in store-operated current (I(SOC)) and SOCE were investigated using whole-cell patch-clamp recording and calcium imaging. I(SOC) is detected in HL-7702 cells and it is inhibited either by 2-Aminoethoxydiphenyl borate (2-APB) or La(3+). Overexpression of STIM1 or Orai1 alone did not induce any change in I(SOC). TRPC1-transfection, however, caused approximate 2.5-fold increase in I(SOC). A large increase (>10-fold) in I(SOC) emerged when both STIM1 and Orai1 were co-transfected into HL-7702 cells. Co-overexpression of STIM1 + TRPC1 also caused >10-fold increase in I(SOC), and addition of Orai1 did not cause any further increase. In HL-7702 cells, TRPC1 and Orai1 take part in SOCE independently of each other. Functional interactions of STIM1 and Orai1 or TRPC1 contribute to I(SOC) activation.


Assuntos
Canais de Cálcio/metabolismo , Sinalização do Cálcio , Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Canais de Cátion TRPC/metabolismo , Canais de Cálcio/biossíntese , Canais de Cálcio/química , Canais de Cálcio/genética , Células Cultivadas , Humanos , Proteínas de Membrana/biossíntese , Proteínas de Membrana/genética , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Proteína ORAI1 , Molécula 1 de Interação Estromal , Canais de Cátion TRPC/biossíntese , Canais de Cátion TRPC/genética
8.
World J Gastroenterol ; 15(33): 4150-5, 2009 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-19725149

RESUMO

AIM: To explore the possibility of using the Non-invasive Micro-test Technique (NMT) to investigate the role of Transient Receptor Potential Canonical 1 (TRPC1) in regulating Ca(2+) influxes in HL-7702 cells, a normal human liver cell line. METHODS: Net Ca(2+) fluxes were measured with NMT, a technology that can obtain dynamic information of specific/selective ionic/molecular activities on material surfaces, non-invasively. The expression levels of TRPC1 were increased by liposomal transfection, whose effectiveness was evaluated by Western-blotting and single cell reverse transcription-polymerase chain reaction. RESULTS: Ca(2+) influxes could be elicited by adding 1 mmol/L CaCl(2) to the test solution of HL-7702 cells. They were enhanced by addition of 20 micromol/L noradrenaline and inhibited by 100 micromol/L LaCl(3) (a non-selective Ca(2+) channel blocker); 5 micromol/L nifedipine did not induce any change. Overexpression of TRPC1 caused increased Ca(2+) influx. Five micromoles per liter nifedipine did not inhibit this elevation, whereas 100 micromol/L LaCl(3) did. CONCLUSION: In HL-7702 cells, there is a type of TRPC1-dependent Ca(2+) channel, which could be detected via NMT and inhibited by La(3+).


Assuntos
Canais de Cálcio/fisiologia , Cálcio/metabolismo , Canais de Cátion TRPC/fisiologia , Linhagem Celular , Humanos , Lantânio/farmacologia , Nifedipino/farmacologia , Norepinefrina/farmacologia
9.
J Gastroenterol Hepatol ; 24(2): 299-306, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19032456

RESUMO

BACKGROUND AND AIM: Magnetic activated cell sorting (MACS) and fluorescent activated cell sorting (FACS) were employed to enrich and detect the gastric cancer cells from a cell line in a model system, and to enrich and detect disseminated tumor cells (DTCs) from bone marrow (BM) of patients with gastric cancer. METHODS: Fifteen patients with benign gastric lesions and 35 patients with gastric cancer who received curative operations between December 2002 and June 2003 were selected. Mononuclear cells were separated from their BM. Cells from cell line OCUM-2M were seeded with 10-grade ratio into mononuclear cells from patients with benign gastric lesion. After labeling by MACS minibeads conjugated with cytokeratin (CK) 7/8 antibodies, anti-CK-fluorescein isothiocyanate (FITC), and anti-CD45-perdinin chlorophyll protein (PerCP), the samples were enriched twice using an MS+/RS+ positive separation column. The FACS analysis was conducted on these samples before and after MACS enrichment. The results were analyzed using clinopathological parameters. RESULTS: Disseminated tumor cells were detected in the BM of 25 (71.43%) patients with gastric cancer. The frequencies of DTCs were 1.38 x 10(-8)-2.40 x 10(-5), 2.19 x 10(-7)-3.70 x 10(-5), 4.01 x 10(-6)-8.57 x 10(-5) in patients with well, moderately, and poorly differentiated carcinoma, respectively (P = 0.026). Disseminated tumor cells in BM had close correlation with tumor tumor-node-metastasis (TNM) stage (P = 0.034) and cancer-free survival (P = 0.035). CONCLUSION: Disseminated tumor cells are very common in the BM of gastric cancer patients. Poor histological differentiation and more advanced TNM stage have more DTCs in the BM of gastric cancer patients. Patients with DTCs tend to have a poor prognosis.


Assuntos
Células da Medula Óssea/patologia , Separação Celular/métodos , Citometria de Fluxo , Separação Imunomagnética , Neoplasias Gástricas/patologia , Adulto , Idoso , Células da Medula Óssea/química , Diferenciação Celular , Linhagem Celular Tumoral , Feminino , Gastrectomia , Humanos , Estimativa de Kaplan-Meier , Queratina-7/análise , Queratina-8/análise , Antígenos Comuns de Leucócito/análise , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Neoplasias Gástricas/química , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/cirurgia , Fatores de Tempo , Resultado do Tratamento
11.
Sheng Wu Gong Cheng Xue Bao ; 21(4): 534-9, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16176088

RESUMO

To construct plasmid of recombinant protein candidate vaccine of respiratory syncytial virus, express it in E. coli, and to investigate its immunogenicity and protective efficacy. A CD8+ T cell epitope from respiratory syncytial virus (RSV) M2 protein F/M2:81 - 95 and the G:125-225 (G1) gene fragments from RSV-G protein containing B cell epitopes were amplified by PCR method and then inserted into the prokaryotic expression vector pET-DsbA after bonding to a linker. The fusion protein DsbA-G1-Linker-F/M2:81-95 (D-G1LF/M2) was expressed successfully in E. coli BL21 (DE3). The product was proved to be RSV-specific by Western-blot. After purified by affinity chromatography on Ni+ Sepharose and renatured by gradient dialysis. D-G1LF/M2 was used to immune BALB/c mice. D-G1LF/M2 induced high anti-D-G1LF/M2 IgG, anti-RSV IgG and neutralizing antibody titers in serum and lung of BALB/c mice, and elicied RSV-specific CTL responses. The IgG subclass distribution revealed that IgG1/IgG2a ratio was 2.66. Viral titration indicated that D-G1LF/M2 could protect BALB/c mice against RSV challenge in lung.


Assuntos
Vacinas contra Vírus Sincicial Respiratório/imunologia , Vírus Sincicial Respiratório Humano/imunologia , Proteínas do Envelope Viral/genética , Proteínas Virais/genética , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Plasmídeos/genética , Plasmídeos/imunologia , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vacinas contra Vírus Sincicial Respiratório/biossíntese , Vacinas contra Vírus Sincicial Respiratório/genética , Vírus Sincicial Respiratório Humano/genética , Proteínas Virais de Fusão/genética
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