Publications by authors named "Tadashi Nishida"

Pharmacological intervention of circadian rhythms is a potentially useful approach for ameliorating various health problems caused by disturbed circadian rhythms including sleep disorder and metabolic diseases. To find compounds that affect circadian rhythms, we screened mushroom extracts using mouse cells expressing the luciferase gene under the control of the mouse Bmal1 promoter. The culture filtrate extract from the basidiomycete Cyclocybe erebia enhanced the oscillation of bioluminescence caused by the expression of the luciferase gene and prolonged the period of bioluminescence.

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The site-specific excision of a target DNA sequence for genetic knockout or lineage tracing is a powerful tool for investigating biological systems. Currently, site-specific recombinases (SSRs), such as Cre or Flp recombination target cassettes, have been successfully excised or inverted by a single SSR to regulate transgene expression. However, the use of a single SSR might restrict the complex control of gene expression.

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Human chromosome fragments (hCFs) and human artificial chromosomes (HACs) can be transferred into mouse ES cells to produce trans-chromosomic (Tc) mice. Although hCFs and HACs containing large genomic DNAs can be autonomously maintained in Tc mice, their retention rate is variable in mouse ES cell lines and Tc mouse tissues, possibly because of centromere differences between the species. To improve the retention rate of artificial chromosomes in mouse cells, we constructed novel mouse artificial chromosome (MAC) vectors by truncating a natural mouse chromosome at a site adjacent to the centromeric region.

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Reduced coenzyme Q(10) (CoQ(10)H(2)) is known as a potent antioxidant in biological systems. However, it is not yet known whether CoQ(9)H(2) could act as an antioxidant in human cells. The aim of this study is to assess whether exogenously added CoQ(9) can protect human liver cells against injuries induced by a water-soluble radical initiator, 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) and a lipid-soluble radical initiator, 2,2'-azobis(2,4-dimethylvaleronitrile) (AMVN).

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Polaprezinc (PZ), a chelate compound consisting of zinc and l-carnosine (Car), is an anti-ulcer drug developed in Japan. In the present study, we investigated whether PZ suppresses mortality, pulmonary inflammation, and plasma nitric oxide (NO) and tumor necrosis factor (TNF)-alpha levels in endotoxin shock mice after peritoneal injection of lipopolysaccharide (LPS), and how PZ protects against LPS-induced endotoxin shock. PZ pretreatment inhibited the decrease in the survival rate of mice after LPS injection.

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Polaprezinc, a chelate compound consisting of zinc and l-carnosine, is clinically used as a medicine for gastric ulcers. It has been shown that induction of heat shock protein (HSP) is involved in protective effects of polaprezinc against gastric mucosal injury. In the present study, we investigated whether polaprezinc and its components could induce HSP70 and prevent acetaminophen (APAP) toxicity in mouse primary cultured hepatocytes.

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We investigated whether pretreatment with geranylgeranylacetone (GGA), a potent heat shock protein (HSP) inducer, could inhibit proinflammatory cytokine liberation and nitric oxide (NO) production in lipopolysaccharide (LPS)-treated murine macrophages. The levels of NO and tumor necrosis factor-alpha (TNF-alpha) released from murine macrophage RAW 264 cells were increased dose- and time-dependently following treatment with LPS (1 microg/ml). GGA (80 microM) treatment 2 h before LPS addition significantly suppressed TNF-alpha and NO productions at 12 h and 24 h after LPS, respectively, indicating that GGA inhibits activation of macrophages.

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The present study was performed to determine whether melatonin protects mouse liver against severe damage induced by acetaminophen (APAP) administration and where melatonin primarily functions in the metabolic pathway of APAP to protect mouse liver against APAP-induced injury. Treatment of mice with melatonin (50 or 100 mg/kg, p.o.

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Mineral concentrations of onions (Allium cepa L.) grown under various conditions, including factors (fertilization, crop year, variety, and provenance), were investigated to clarify how much each factor contributes to the variation of their concentrations. This was because the mineral concentrations might be affected by various factors.

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Geranylgeranylacetone (GGA), an anti-ulcer drug, has been reported to induce heat shock protein (HSP) 70 in several animal organs. The present study was performed to determine whether GGA protects mouse liver against acetaminophen (APAP)-induced injury and whether it has potential as a therapeutic agent for APAP overdose. Hepatic damage was induced by single oral administration of APAP (500 mg/kg).

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The present study was performed to determine whether oral pretreatment with geranylgeranylacetone (GGA) inhibits proinflammatory cytokine liberation and nitric oxide (NO) production in lipopolysaccharide (LPS)-treated rats and protects rats against death from LPS-induced endotoxin shock, and whether such protection by GGA is related to heat shock protein (HSP) 70 induction in multiple organs of rats. GGA (200 mg/kg) was given orally to rats. LPS (20 mg/kg) was administered intraperitoneally 4, 8, 16, or 24 h after GGA administration.

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A growing body of evidence suggests that phosphatidylserine (PS) oxidation is linked with its transmembrane migration from the inner to the outer leaflet of the plasma membrane during apoptosis. However, there is no direct evidence for the presence of oxidized PS (PSox) on the surface of cells undergoing apoptosis. The present study was performed to detect PSox externalized to the cell surface after Fas engagement in Jurkat cells.

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