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591.
Ji‐Seon Yoon Koji Nishifuji Sinpei Ishioroshi Kaori Ide Toshiroh Iwasaki 《Veterinary dermatology》2013,24(1):84-e22
Background – Seborrhoea is a clinical condition resulting in excessive lipid and/or scale on the skin and is a common and important skin disease of dogs. However, there is little information on the skin surface lipid composition of dogs with seborrhoea. Hypothesis/Objectives – To compare skin surface lipid profiles in normal and seborrhoeic shih tzu dogs. Methods – Fourteen client‐owned dogs (seven seborrhoeic and seven normal) were investigated. Lipids in sebaceous glands (SGs) were extracted from homogenized tissues of SG hyperplasia. Surface lipid was collected by tape stripping [stratum corneum (SC)‐enriched fraction] and acetone‐wetted cotton swab (acetone‐extracted fraction). Lipids in SGs, SC‐enriched fractions and acetone‐extracted fractions were evaluated by high‐performance thin‐layer chromatography. Results – Lipids in SGs mainly consisted of cholesterol esters, wax esters and triglycerides, whereas lipids in the SC‐enriched fraction mainly consisted of ceramides. The acetone‐extracted fraction contained a mixture of lipid classes recognized in SG‐ and SC‐enriched fractions. In seborrhoeic dogs, concentrations of wax esters and triglycerides in the acetone‐extracted fraction were significantly higher than in control dogs (P = 0.0285). Amounts of total ceramides (in micrograms) per milligram of SC were not significantly different between the two groups (P = 0.5204). Interestingly, two unknown ceramide fractions, which accounted for 20% of the total ceramides, were recognized exclusively in seborrhoeic dogs. Conclusions and clinical importance – These results provide evidence that the skin surface lipid profiles are altered in shih tzu dogs with seborrhoea. 相似文献
592.
593.
Historical Profiles of Trace Element Concentrations in Mangrove Sediments from the Ba Lat Estuary,Red River,Vietnam 总被引:1,自引:0,他引:1
Nguyen Tai Tue Tran Dang Quy Atsuko Amano Hideki Hamaoka Shinsuke Tanabe Mai Trong Nhuan Koji Omori 《Water, air, and soil pollution》2012,223(3):1315-1330
Historical profiles of trace element concentrations were reconstructed from two mangrove sediment cores collected within the
Ba Lat Estuary (BLE), Red River, Vietnam. Chronologies of sediment cores were determined by the 210Pb method, which showed that each respective sediment core from the south and north entrances of BLE provided a record of
sediment accumulation spanning approximately 100 and 60 years. The profiles of Pb, Zn, Cu, Cr, V, Co, Sb, and Sn concentrations
markedly increased from the years of the 1920s–1950s, and leveled out from 1950s–1980s, and then gradually decreased from
1980s to present. The profiles of Cd and Ag concentrations increased from 1920s–1940s, and then decreased from 1940s to present.
The profile of Mo concentrations progressively increased from 1920s–1980s, then decreased to present. The Mn concentrations
failed to show a clear trend in both sediment cores. Results from contamination factors, Pearson’s correlation, and hierarchical
cluster analysis suggest that the trace elements were likely attributed to discharge of untreated effluents from industry,
domestic sewage, as well as non-point sources. Pollution Load Index (PLI) revealed levels higher than other mangrove sediment
studies, and the long-term variations in PLI matched significant socioeconomic shifts and population growth in Vietnam. Geoaccumulation
Index showed that mangrove sediments were moderately polluted by Pb and Ag, and from unpolluted to moderately polluted by
Zn, Cu, and Sb. The concentrations of Pb, Zn, Cu, Cr, and Cd exceeded the threshold effect levels and effect range low concentrations
of sediment quality guidelines, implying that the sediments may be occasionally associated with adverse biological effects
to benthic organisms. 相似文献
594.
Haruhisa Suga Rina Okumura Maho Ikawa Masafumi Shimizu Koji Kageyama 《Plant pathology》2022,71(3):602-610
Members of the Fusarium graminearum species complex are known to cause head blight of wheat. A natural nonpathogenic mutant, strain Fa0233007, was found in the strain collection of the Japanese F. graminearum species complex. In addition, this strain cannot form perithecia. Complete linkage of these deficiencies in the progenies obtained from crossing a wild-type strain and the mutant strain suggested that a single genomic locus was responsible for deficiencies in both traits. The locus was mapped to chromosome 1 using sequence-tagged markers. An NADPH oxidase gene (NoxA, FGSG00739) was identified in the mapped region, and a 2-bp deletion that results in premature termination of the open reading frame was detected in the gene. Both pathogenicity and perithecium formation were recovered by FGSG00739 complementation in the mutant strain. 相似文献
595.
596.
Amino acids in natural proteins have a chiral, asymmetric center at the alpha carbon that is of the L-configuration. The sugar backbone of natural RNAs are also homochiral, but of the D-configuration. Because protein synthesis requires the aminoacylation of RNA, it is this step that could have provided chiral selectivity. Here we show that an RNA minihelix was aminoacylated by an aminoacyl-phosphate-D-oligonucleotide with a clear preference for L- as opposed to D-amino acids. A mirror-image RNA system showed the opposite selectivity. These results suggest the possibility that the selection of L-amino acids for proteins was determined by the stereochemistry of RNA. 相似文献
597.
The objective of this experiment was to determine the ensiling characteristics, nutrient composition and nutritive value of Chinese yam by-product (CYBP) silage treated without additive (Control), with lactic acid bacteria (LY), with dried beet pulp (BY), or with mixtures of lactic acid bacteria and dried beet pulp (LBY) for a fermentation period of 150 days. The nutritive value of CYBP silage was studied in an in vivo digestibility trial using wethers in a 4 × 4 Latin square design. Addition of lactic acid bacteria and/or dried beet pulp greatly improved fermentation quality of CYBP silage. The pH was reduced to below 4.0 and lactic acid was produced at above 4.6% on dry matter basis. There were no statistical differences among treatments in the digestibilities of dry matter, organic matter, crude protein and energy in the silages, but neutral detergent fiber and acid detergent fiber digestibility were higher ( P < 0.001) in wethers fed BY and LBY silages compared to the control and LY silages. It was estimated that total digestible nutrient and digestible energy in the CYBP silage averaged 79.1% and 14.3 MJ/kg on dry matter basis. The study suggests that CYBP can be well preserved by making a silage and it is a good potential energy source for ruminant diets. 相似文献
598.
599.
Ito A Hattori M Yoshida T Watanabe A Sato R Takahashi K 《Journal of agricultural and food chemistry》2006,54(26):10191-10196
The binding of an amino acid, glycine (Gly), alanine (Ala), epsilon-aminocaproic acid (-AC), monosodium glutamate (GluNa), or lysine (Lys), to starch was examined by a biomolecular interaction analyzer (IAsys). A starch sample (ATS) hydrolyzed to an extent of 1% hydrolysis rate with 15% sulfuric acid was used as a model starch for the binding examination. The reducing end of ATS was oxidized by the Somogyi reagent, and the conversion of the reducing end to the carboxyl group of ATS was confirmed by a carboxylic acid fluorescence labeling reagent. The oxidized ATS was immobilized to the amino group of a sensor cuvette by using water-soluble carbodiimide and N-hydroxysuccinimide through an amide bond. The IAsys examination showed that Gly, Ala, and epsilon-AC scarcely bound to the immobilized starch chains but that GluNa and Lys favorably bound with their increasing concentrations. The relative binding index (RBI) of each amino acid was defined by the ratio of the slope of the linear regression equation between the binding response and the concentration for each amino acid to that for Gly. Because the relationships between the RBI and the pasting characteristics (pasting temperature, peak viscosity, breakdown, and swelling index) could each be expressed by a linear regression equation with a high correlation coefficient, it is concluded that the regulation of the pasting behavior of starch with an amino acid is caused by binding of the amino acid to the starch chains. 相似文献
600.
Effective sample pretreatment procedures based on solid-phase extraction (SPE) for multiresidue determination of seven neonicotinoid insecticides in agricultural products were investigated. After extraction with acetone and concentration, the insecticides in aqueous sample extracts were transferred into organic solvent phases with a Chem Elut SPE cartridge. Finally, the eluate from the cartridge was cleaned up with a SPE cartridge packed with graphitized carbon black and aminopropyl silica gel, which showed a higher cleanup efficiency than the classical silica gel SPE cartridge. Seven insecticides were separated on a reversed-phase C18 column and a gradient system of methanol and phosphate solution based on high-performance liquid chromatography. The established multiresidue determination has been applied to several artificially spiked agricultural samples, with the result that the average recoveries were excellent, with the exception of nitenpyram. The limit of detection of the method ranged from 0.01 to 0.03 mg/kg for the insecticides. 相似文献