Food protective and color alteration effects of acaricidal aldehydes on Tyrophagus putrescentiae (Schrank).

The activities of benzaldehyde isolated from Prunus persica seeds and of commercially available aldehydes against Tyrophagus putrescentiae (a stored-food mite) adults were examined and compared with those of the synthetic acaricides benzyl benzoate and N,N-diethyl-m-toluamide. On the basis of the 50% lethal dose (LD50), the compound most toxic to T. putrescentiae adults was salicylaldehyde (LD50 of 1.02 microg/cm2) followed by cinnamaldehyde (1.66 microg/cm2), benzaldehyde (4.23 microg/cm2), phthaldialdehyde (5.16 microg/cm2), benzyl benzoate (9.75 microg/cm2), and N,N-diethyl-m-toluamide (16.26 micorg/cm2). Benzaldehyde was about 2.3 and 3.8 times more toxic than benzyl benzoate and N,N-diethyl-m-toluamide, respectively, against T. putrescentiae adults. These results indicated that benzaldehyde isolated from P. persica seeds and the three aldehydes (cinnamaldehyde, salicylaldehyde, and phthaldialdehyde) are useful as lead compounds for developing acaricidal agents against T. putrescentiae adults. The color of the T. putrescentiae cuticle was changed by treatment with cinnamaldehyde, salicylaldehyde, and phthaldialdehyde.

CDNA for an immune response gene encoding low molecular weight polypeptide from flounder, Paralichthys olivaceus.

The cDNA for an immune response gene encoding the low molecular weight polypeptide (LMP7) was cloned and sequenced from a flounder (Paralichthys olivaceus) leukocyte cDNA library. The cDNA clone was 1,160 bp, and composed of an open reading frame of 822 bp that corresponded to a protein of 273 amino acid residues with a calculated mass of 30.5 kDa. The ScanProsite search indicated that the deduced amino acid sequence from the flounder LMP7 contains a proteasome beta-type subunit signature, which is well conserved during evolution. The sequence shares a high degree of identity with other LMP7 sequences varying from a 66% identity with zebra fish (Danio renio) to a 57% identity with the African clawed frog (Xenopus laevis), which was confirmed from a phylogenetic tree. A reverse transcription-polymerase chain reaction (RT-PCR) was used to determine tissue specificity, and the expression of LMP7 was detected from the liver, kidney, leukocyte, and spleen of the flounder.

The effect of lipopolysaccharide on enhanced inflammatory process with age: Modulation of NF-κB.

Oxidative stress is thought to be a causative factor for age-related damage in a wide variety of cellular constituents that can lead to dysfunction and various pathological conditions, including the inflammatory process. At the molecular level, the redox-sensitive transcription factor, NF-κB plays a key role in the regulation of the inflammatory process, along with cytokines, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS). We studied the mechanism underlying the modulation of the inflammatory reaction with age by investigating NF-κB activation and the expression of COX-2, iNOS, and cytokines genes in hepatic tissues isolated from young and old rats. We expanded our investigation of these factors in rats injected with the inflammatory activator, lipopolysaccharide (LPS). Data showed that NF-κB activity was up-regulated with age and was further enhanced by LPS injection, indicating an increased susceptibility and sensitivity to the inflammatory stimulus with age. To explore further the molecular events leading to NF-κB activation, we investigated the inhibitory component of NF-κB complex, IκB. Cytosolic IκBα, but not IκBß, was significantly decreased in both old and LPS-treated rats, signifying the enhanced migration of cytosolic NF-κB complex into the nucleus following dissociation from the inhibitor. The appearance of the polypeptide, p65, as determined in the nucleus, corresponded with the change in IκBα, providing further supporting evidence for the molecular process involved in NF-κB activation. Our additional investigation of two proinflammatory-related enzymes, COX-2 and iNOS, and three cytokines, interleukin-1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor-α, clearly showed aged-related increases, in corroboration with the NF-κB activation. Our results demonstrated that LPS injection caused the enhanced gene expression of inducible proinflammatory proteins, COX-2 and iNOS through NF-κB activation.