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Biomedical subjects

Ping Hua

Publications and source records attributed to Ping Hua.

13 recordsLinked to original sources
PubMed2006

[Four main schools of thought and analysis in studies of channels and collaterals].

OBJECTIVE: To summarize 4 schools of thought in studies of meridians. METHODS: Consult literature and review the history of studies of meridians. RESULTS: The studies of meridians in the past dozens years at home and abroad have gradually formed four main theories, namely the nerve-conduction meridian theory of neurophysiology, body fluid circulation meridian theory of the physio-biochemistry, bio-field meridian theory of biophysics, and the connective tissue structure meridian theory of the overall-gap viewpoint, which are summarized and analyzed.

Acupuncture Points↗
PubMed2005

Automated water analyser computer supported system (AWACSS) Part I: Project objectives, basic technology, immunoassay development, software design and networking.

A novel analytical system AWACSS (automated water analyser computer-supported system) based on immunochemical technology has been developed that can measure several organic pollutants at low nanogram per litre level in a single few-minutes analysis without any prior sample pre-concentration nor pre-treatment steps. Having in mind actual needs of water-sector managers related to the implementation of the Drinking Water Directive (DWD) (98/83/EC, 1998) and Water Framework Directive WFD (2000/60/EC, 2000), drinking, ground, surface, and waste waters were major media used for the evaluation of the system performance. The instrument was equipped with remote control and surveillance facilities. The system's software allows for the internet-based networking between the measurement and control stations, global management, trend analysis, and early-warning applications. The experience of water laboratories has been utilised at the design of the instrument's hardware and software in order to make the system rugged and user-friendly. Several market surveys were conducted during the project to assess the applicability of the final system. A web-based AWACSS database was created for automated evaluation and storage of the obtained data in a format compatible with major databases of environmental organic pollutants in Europe. This first part article gives the reader an overview of the aims and scope of the AWACSS project as well as details about basic technology, immunoassays, software, and networking developed and utilised within the research project. The second part article reports on the system performance, first real sample measurements, and an international collaborative trial (inter-laboratory tests) to compare the biosensor with conventional anayltical methods.

Algorithms↗
PubMed2005

Automated Water Analyser Computer Supported System (AWACSS) Part II: Intelligent, remote-controlled, cost-effective, on-line, water-monitoring measurement system.

A novel analytical system AWACSS (Automated Water Analyser Computer Supported System) based on immunochemical technology has been evaluated that can measure several organic pollutants at low nanogram per litre level in a single few-minutes analysis without any prior sample pre-concentration or pre-treatment steps. Having in mind actual needs of water-sector managers related to the implementation of the Drinking Water Directive (DWD) [98/83/EC, 1998. Council Directive (98/83/EC) of 3 November 1998 relating to the quality of water intended for human consumption. Off. J. Eur. Commun. L330, 32-54] and Water Framework Directive (WFD) [2000/60/EC, 2000. Directive 2000/60/EC of the European Parliament and of the Council of 23 October 2000 establishing a framework for Community action in the field of water policy. Off. J. Eur. Commun. L327, 1-72], drinking, ground, surface, and waste waters were major media used for the evaluation of the system performance. The first part article gave the reader an overview of the aims and scope of the AWACSS project as well as details about basic technology, immunoassays, software, and networking developed and utilised within the research project. The second part reports on the system performance, first real sample measurements, and an international collaborative trial (inter-laboratory tests) to compare the biosensor with conventional anayltical methods. The systems' capability for analysing a wide range of environmental organic micro-pollutants, such as modern pesticides, endocrine disrupting compounds and pharmaceuticals in surface, ground, drinking and waste water is shown. In addition, a protocol using reconstitution of extracts of solid samples, developed and applied for analysis of river sediments and food samples, is presented. Finally, the overall performance of the AWACSS system in comparison to the conventional analytical techniques, which included liquid and gas chromatographic systems with diode-array UV and mass spectrometric detectors, was successfully tested in an inter-laboratory collaborative trial among six project partners.

Algorithms↗
PubMed2005

[Study on the effect of theaflavins on the adhesion between monocyte and endothelial cells].

The effect of theaflavins (TFs) on the adhesion between monocyte and endothelial cells induced by oxidized low density lipoprotein was studied. The experiments of cells-adhesion,the cells ELISA were applied. The results showed that TFs could significantly inhibit the adhesion between monocyte and endothelial cells, and the expression of cell adhesion molecule (ICAM-1) and vascular cell adhesion molecule (VCAM-1). That maybe one of the mechanisms in antiatheroclerosis and antiadhesion between monocyte and endothelial cells.

Antioxidants↗
PubMed2005

[Expression of vascular endothelial growth factor C and cyclooxygenase-2 in non-small-cell lung carcinoma and their clinical significance].

OBJECTIVE: To investigate the expression of vascular endothelial growth factor-C (VEGF-C) and cyclooxygenase-2 (COX-2) proteins, and their relationship with biological behaviors of non-small-cell lung carcinoma (NSCLC). METHODS: Immunohistochemical staining was used to detect the expression of VEGF-C and COX-2 proteins in 77 cases of NSCLC. The relationship was analyzed between the expression of VEGF-C, COX-2 and lymphatic vessel density (LVD), tumor size, histological type, differentiation, lymph node metastasis, clinical recurrence and survival time of the patients. RESULTS: Out of 77 cases of NSCLC, 45 cases and 29 cases showed positive expression of VEGF-C and COX-2 proteins, respectively. The expression rates of VEGF-C and COX-2 protein were 58.4% and 37.7%, respectively. The expression of VEGF-C protein was correlated negatively with the degree of differentiation of NSCLC (P < 0.05). The expression of VEGF-C was positively correlated with lymph node metastasis, LVD and tumor size (P < 0.01). The survival time of the patients was negatively correlated with the expression of VEGF-C (P < 0.01). The expression of COX-2 was positively correlated with LVD (P < 0.01). The survival time of the patients was negatively correlated with the expression of COX-2 (P < 0.05). CONCLUSION: The expression of VEGF-C and COX-2 proteins are closely correlated with the biological behaviors of NSCLC, especially VEGF-C protein. Its high expression suggests probable lymph node metastasis and poor prognosis.

Adult↗
PubMed2003

Estrogen response element-independent regulation of gene expression by genistein in intestinal cells.

Isoflavone, genistein, was shown to have antioxidant and antitumor activities. We have reported the stimulatory effect of genistein on the expression of antioxidant and metal-binding protein, metallothionein IIA (MTIIA), in human intestinal Caco-2 cells. Genistein has been shown to up-regulate the expression of other genes through estrogen response element (ERE) but the ERE sequence is not in the MTIIA promoter. In this paper, we investigated the ERE-independent mechanism that mediates the stimulatory effect of genistein. Genistein enhanced the expression of human MTIIA promoter (up to -426)-containing reporter genes, thus supporting a promoter-specific transcriptional regulation. A shorter MTIIA promoter (-83 to +27) was found to be able to mediate the full reporter gene response to genistein in a dose- and time-dependent fashion. Further deletion and mutation analysis revealed that the GC-rich Sp1 binding sequence was the target of the stimulation. Genistein was known to bind to estrogen receptors (ER). When cells were cotransfected with ER beta, the stimulatory effect of genistein on the reporter gene containing the GC-rich promoter sequence increased further and a similar result was observed for breast cancer MCF-7 cells. Inhibitors of protein kinase A could block the response to genistein but the phosphorylation of Sp1 protein per se was not affected by the genistein treatment. Our observation could help to evaluate the biological significance of genistein, which is used widely as a supplement.

Antineoplastic Agents↗
PubMed2003

Cyclooxygenase-2 expression and prostanoid biogenesis reflect clinical phenotype in human colorectal fibroblast strains.

Up-regulated cyclooxygenase (COX)-2 expression and prostaglandin E2 (PGE2)synthesis contribute causally to the early stages of colorectal neoplasia and carcinogenesis, yet COX-2 expression is barely detectable in normal and premalignant colorectal epithelium. Rather, COX-2 expression in nonmalignant colonic tissue is probably confined to subepithelial cells, such as fibroblasts. We established a panel of 33 primary subepithelial fibroblast strains from human colonoscopic biopsies of normal colon (group I), normal segments of colons that harbored synchronous advanced neoplasms in remote segments (group II), advanced neoplasms (group III), and segments of active ulcerative colitis (group IV). In group I strains, mean basal and peak PGE2 levels after 24 h of interleukin (IL)-1beta stimulation were 5.4 +/- 1.1 and 32.8 +/- 4.9 ng/mg protein, respectively. Mean IL-1beta-stimulated peak levels in groups II, III, and IV strains were, respectively, 6-, 9-, and 7-fold greater than that in group I (P < 0.001 for each comparison), and inductions of COX-2 mRNA and protein were consistent with these findings. IL-1beta-mediated stimulation of PGE2 was fully blocked in the presence of a nonselective COX inhibitor (indomethacin) or a selective COX-2 inhibitor (NS-398). IL-1beta treatment elicited from group I (normal) and group III (cancer-associated) fibroblasts, respectively, approximately 2- and 3-fold inductions of COX-2 transcriptional activity and approximately 1.4- and 1.7-fold inductions of COX-2 promoter activity. This modestly greater COX-2 transcription rate could not alone account for the dramatically higher levels of COX-2 mRNA and protein and PGE2 in cancer-associated compared with normal fibroblasts. However, incubation of fibroblasts with PGE2 after IL-1beta stimulation prolonged COX-2 mRNA half-life from approximately 1 to 9 h. Our results strengthen the evidence that fibroblasts and other mesenchymal cells are the source of COX-2 expression in normal and premalignant colorectal tissue. Group II fibroblasts from normal segments of colons that harbored synchronous remote advanced neoplasms behaved like group III fibroblasts from advanced neoplasms and not group I fibroblasts from normal colons. We hypothesize that the effects of modestly greater COX-2 transcription in groups II-IV fibroblasts yield corresponding modest increases in PGE2 synthesis whose effects are progressively amplified through robust stabilization of COX-2 mRNA.

Cells, Cultured↗
PubMed2002

Kinetic properties of Kv4.3 and their modulation by KChIP2b.

KChIPs are a family of Kv4 K(+) channel ancillary subunits whose effects usually include slowing of inactivation, speeding of recovery from inactivation, and increasing channel surface expression. We compared the effects of the 270 amino acid KChIP2b on Kv4.3 and a Kv4.3 inner pore mutant [V(399, 401)I]. Kv4.3 showed fast inactivation with a bi-exponential time course in which the fast time constant predominated. KChIP2b expressed with wild-type Kv4.3 slowed the fast time constant of inactivation; however, the overall rate of inactivation was faster due to reduction of the contribution of the slow inactivation phase. Introduction of [V(399, 401)I] slowed both time constants of inactivation less than 2-fold. Inactivation was incomplete after 20s pulse durations. Co-expression of KChIP2b with Kv4.3 [V(399, 401)I] slowed inactivation dramatically. KChIP2b increased the rate of recovery from inactivation 7.6-fold in the wild-type channel and 5.7-fold in Kv4.3 [V(399,401)I]. These data suggest that inner pore structure is an important factor in the modulatory effects of KChIP2b on Kv4.3 K(+) channels.

Animals↗
PubMed2002

Ca2+- and PKC-dependent stimulation of PGE2 synthesis by deoxycholic acid in human colonic fibroblasts.

We investigated prostanoid biogenesis by human colonic fibroblasts (CCD-18Co cells and nine primary fibroblast cultures) exposed to a primary (cholic, CA) or a secondary (deoxycholic, DCA) bile acid. Basal PGE2 levels in CCD-18Co cultures and fibroblast strains initiated from normal and adenocarcinomatous colon, respectively, were 1.7 +/- 0.3, 4.0 +/- 2.0, and 15.0 +/- 4.8 ng/mg protein. Peak levels 24 h after exposure to DCA (300 microM) rose, respectively, seven-, six- and sevenfold, but CA elicited no such responses. Increases in PGE2 synthesis were preceded by sequential increases in PGH synthase-2 mRNA and protein expression and were fully prevented by a nonselective (indomethacin) or a selective (celecoxib) nonsteroidal anti-inflammatory drug. DCA, but not CA, caused abrupt, transient increases in fibroblast intracellular Ca2+ concentration ([Ca2+]i) approximately 1 min after exposure. Increased [Ca2+]i was required for DCA-mediated induction of PGE2 synthesis, and protein kinase C was a further essential component of this signaling pathway. Colonic fibroblasts may be a major target for prostanoid biogenesis induced by fecal bile acids and, potentially, other noxious actions of these agents.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2002

[Effect of trypsin on the rat keratinocyte separation and subculture].

The effect of trypsin on the separation an subculture of the keratinocytes was investigated in this work. It was found that when 0.25% trypsin was employed for 5 minutes to separate keratinocytes, the number of active keratinocytes and the cells capable of forming colony were higher than those of other experimental conditions. The maximum attached ratio of primary keratinocytes was obtained when skin tissues were treated at 0.05% concentration of trypsin. With the increase of the trypsin concentrations, the attached ratio, attachment rate constant, and colony forming efficiency were all increased. Thus, 0.25% concentration of trypsin was recommended for separating and subculturing the keratinocytes.

Animals↗
PubMed2002

[Calcium-regulated growth and differentiation of the mouse epidermal keratinocytes].

The effect of the calcium ion (Ca2+) on the growth and differentiation of the mouse epidermal keratinocytes cultured in serum-free medium was investigated. It was found that the optimal level of calcium ion in the medium was about 0.2 mmol/L. Under such a culture condition the colony forming efficiency, attachment percentage, percentage of the cells with cornified envelops, and percentage of the senesced cells were measured to be about 10.8%, 30.8%, 5.1%, and 26.8%, respectively. However, the Ca2+ concentrations in the medium above 0.6 mmol/L resulted in significant differentiation and senescence of the keratinocytes, which was found to be harmful for keratinocyte growth and expansion in vitro.

Animals↗
PubMed2002

[The effect of antioxidants on the in vitro life-span of keratinocyte].

The effect of antioxidants on the in vitro life span of mouse keratinocytes was investigated in this work. It was found that the life span of the keratinocytes cultured in the medium supplemented with antioxidants was extended significantly. The most beneficial antioxidant used in this work was the mercaptoethanol, followed by the catalase and SOD. However, the growth rates of keratinocytes in vitro under all the experimental conditions still declined with the culture time. It was also found that the antioxidants added in the medium were also helpful to enhance the keratinocyte colony formation. In addition, the aging kinetics of the mouse epidermal keratinocytes in vitro were analyzed, and finally the aging rate constants corresponding to antioxidants used were calculated.

Animals↗