Biomedical subjects

Ken-ichiro Kamei

Publications and source records attributed to Ken-ichiro Kamei.

4 recordsLinked to original sources

PubMed2006

Transgenic mouse for conditional, tissue-specific Cox-2 overexpression.

We constructed a cyclooxygenase-2 (Cox-2) conditional overexpression transgenic mouse (Cox-2 COE). The transgene contains a CAG promoter driving the Cox-2 and humanized Renilla luciferase (hRL) coding regions, linked by an internal ribosomal entry site. The promoter is followed by a loxP-flanked sequence containing enhanced green fluorescent protein (EGFP), a neomycin selection cassette, and a transcriptional/translational STOP sequence. In the presence of Cre recombinase the loxP-flanked sequence is excised. Cox-2/hRL expression can be monitored repeatedly and noninvasively in vivo by imaging hRL activity. To demonstrate conditional Cox-2 and hRL expression, a nonreplicating adenovirus carrying Cre recombinase (Ad.CMV.Cre) was injected intravenously; hepatic Cox-2 expression and hRL signal were elevated. Cox-2 COE embryonic fibroblasts express both Cox-2 and hRL following Ad.CMV.Cre infection. PGE(2) production is also increased following Ad.CMV.Cre infection of Cox-2 COE embryo fibroblasts. Cox-2 COE mice should be valuable for the study of Cox-2 overexpression in cardiovascular disease, acute and chronic inflammatory responses, neurodegenerative diseases, and cancer.

Adenoviridae↗

PubMed2004

The construction of endothelial cellular biosensing system for the control of blood pressure drugs.

In order to assess blood pressure control drugs, the endothelial cellular biosensing system for assessing blood pressure control drugs was constructed. This system consists of human umbilical vein endothelial cells (HUVEC) on a polyion-coated gold electrode, a platinum counter electrode and an Ag/AgCl reference electrode. Nitric oxide (NO) as an indicator of blood vessel relaxation was detected with a polyion-coated electrode in the system. The NO detection limit of this electrode was 8.4 nM by differential pulse voltammetry (DPV). The drugs of blood pressure control (acetylcholine chloride (AcChCl), NOC 7 and NG-monomethyl-L-arginine (L-NMMA)) were assessed with this endothelial cellular biosensing system. One milli molar of AcChCl make NO released from HUVEC stimulated by activating endothelial nitric oxide synthase (eNOS) in HUVEC. In the case of 5 mM of L-NMMA, NO releasing was inhibited by inhibiting eNOS activation by 1 mM of AcChCl. NOC 7 immediately released NO regardless of eNOS activation in endothelial cells.

Antihypertensive Agents↗

PubMed2003

Development of immune cellular biosensing system for assessing chemicals on inducible nitric oxide synthase signaling activator.

An immune cellular biosensing system has been constructed to assess immunomodulating effects of chemicals. Production of nitric oxide in the immune cellular biosensing system was used as readout of an immune cellular response for assessing the immunomodulating effects of chemicals. The macrophage-like cell line RAW264.7, which has signaling pathways of inducible nitric oxide synthase, was employed in the cellular biosensing system. The immune cellular biosensing system consisted of a Pt counter electrode, an Ag/AgCl reference electrode, and a gold electrode onto which a polyion complex layer was coated to allow adherence of the RAW264.7 cells. As the results of evaluating effects of a polyion complex layer on cell viabilities by using WST-8 assay, the polyion complex layer did not affect RAW264.7 cells. The polyion-coated gold electrode could measure NO without the drawback of electrochemical interference that occurs with differential pulse voltammetry. The detection limit of the immune cellular biosensing system was 4.2 nM released NO as measured by double potential step chronoamperometry. The potent immune activating abilities of lipopolysaccharide and interferon-gamma could be assessed by the cellular biosensing system; NO release from cells was detected within 600 ms.

Adjuvants, Immunologic↗

PubMed2003

Cellular biosensing system for assessing immunomodulating effects on the inducible nitric oxide synthase (iNOS) cascade.

A cellular biosensing system has been constructed to assess the biological safety/toxicity of chemicals. Detection of nitric oxide (NO) by the cellular biosensing system was used as a readout for assessing the immunomodulating effects of various chemicals, because some are known to induce NO synthase (iNOS) activity thereby increasing NO production. The macrophage-like cell line, RAW264.7, was cultured on the electrode coated with a polyion complex layer. The potent immune activating abilities of lipopolysaccharide could be verified by the cellular biosensing system: NO release from cells was detected within 600 ms by double potential step chronoamperometry.

Adjuvants, Immunologic↗