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311.
Policosanols, long-chain alcohols, have many beneficial physiological activities. Contents and compositions in perilla seeds (Perilla frutescens) produced in Korea and China were determined. Waxy materials were extracted from perilla seeds using hot hexane. Yield of the waxy materials from perilla seeds was 72.1 mg/100 g of dry weight. Contents and compositions of the waxy materials and policosanols were identified and quantified by TLC, HPLC, and GC. Major components of the waxy materials from Korean and Chinese perilla seeds were policosanols (25.5 and 34.8%, respectively), hydrocarbons (18.8 and 10.5%), wax esters, steryl esters and aldehydes (53.0 and 49.8%), acids (1.7 and 2.1%), and triacylglycerols (1.0 and 2.9%), determined by HPLC. For comparison, waxy materials of sesame seeds were also analyzed. Yield of the waxy materials from sesame seeds were 8.6 mg/100 g. Less than 5% policosanols were detected in the waxy materials extracted from sesame seeds produced in Korea and China. Wax esters or steryl esters accounted for 93-95% of the sesame waxy materials. Policosanols in the perilla seeds were composed of 67-68% octacosanol, 16-17% hexacosanol, 6-9% triacontanol, and others.  相似文献   
312.

Purpose

This study is aimed to assess the long-term leaching of inorganic constituents from structural fills composed of reused coal bottom ash in Korea and identify key parameters that affect the amount of the constituents leached.

Materials and methods

A model for the prediction of long-term leaching by percolation of stormwater through a structural fill is adopted and used. The long-term leaching model is applied to five field sites in Korea using site-specific parameters obtained for each site and coal bottom ash specific parameters determined using column studies for two coal bottom ash samples collected from coal-fired power plants.

Results and discussion

The long-term leaching of trace inorganic constituents, As, Cu, Sb, and Zn, is variable among the sites primarily due to the variation in the total amount of leachable constituents and application depth of a structural fill. First-order leaching rate constant is also one of the key parameters when the leaching rate is relatively small. Because of the significant variability in the leaching rate constants and application depths, the time for the leachate constituent concentration to reach half the initial value, t 50%, ranges from less than a year to more than hundreds of years for the studied sites and constituents.

Conclusions

The long-term leaching characteristics of the trace inorganic constituents are predicted to significantly vary by the type of reused bottom ash and the site conditions, suggesting the need to determine the model parameters in a case-specific manner.
  相似文献   
313.
Hepatocutaneous syndrome (HS) is an uncommon skin disorder that occurs in conjunction with liver disease and is diagnosed based on decreased plasma concentrations of amino acids and the histopathology of skin lesions. The survival period generally is <6 months. A 10‐year‐old castrated male Maltese dog was presented for evaluation of lethargy, polyuria, polydipsia, and skin lesions including alopecia, erythema, and crusts. Based on increased liver enzyme activity, low plasma amino acid concentrations, and findings from liver cytology and skin biopsy, the dog was diagnosed with HS. In addition to administration of antioxidants, hepatoprotective agents, and amino acids IV, allogenic adipose tissue‐derived mesenchymal stem cells were infused 46 times over a 30‐month period: 8 times directly into the liver parenchyma guided by ultrasonography and the remainder of the times into peripheral veins. After commencing stem cell therapy, the dog's hair re‐grew and the skin lesions disappeared or became smaller. During ongoing management, the patient suddenly presented with anorexia and uncontrolled vomiting, and severe azotemia was observed. The dog died despite intensive care. On necropsy, severe liver fibrosis and superficial necrolytic dermatitis were observed. The dog survived for 32 months after diagnosis. A combination of amino acid and stem cell therapy may be beneficial for patients with HS.  相似文献   
314.
315.
An ubiquinone derivative, pseudoalteromone A (1), has been isolated from two marine-derived Pseudoalteromonas spp., APmarine002 and ROA-050, and its anti-melanogenesis activity was investigated. The anti-melanogenic capacity of pseudoalteromone A was demonstrated by assessing the intracellular and extracellular melanin content and cellular tyrosinase activity in the B16 cell line, Melan-a mouse melanocyte cell line, and MNT-1 human malignant melanoma cell line. Treatment with pseudoalteromone A (40 μg/mL) for 72 h reduced α-melanocyte-stimulating hormone (α-MSH)-induced intracellular melanin production by up to 44.68% in B16 cells and 38.24% in MNT-1 cells. Notably, pseudoalteromone A induced a concentration-dependent reduction in cellular tyrosinase activity in B16 cell, and Western blot analyses showed that this inhibitory activity was associated with a significant decrease in protein levels of tyrosinase and tyrosinase-related protein 1 (Tyrp-1), suggesting that pseudoalteromone A exerts its anti-melanogenesis activity through effects on melanogenic genes. We further evaluated the skin-whitening effect of pseudoalteromone A in the three-dimensional (3D) pigmented-epidermis model, MelanoDerm, and visualized the 3D distribution of melanin by two-photon excited fluorescence imaging in this human skin equivalent. Collectively, our findings suggest that pseudoalteromone A inhibits tyrosinase activity and expression and that this accounts for its anti-melanogenic effects in melanocytes.  相似文献   
316.
Four new chlorinated meroterpenoids, merochlorins G−J (1−4), and 10, a dihydronaphthalenedione precursor, along with known merochlorins A (5) and C−F (6−9), were obtained from cultivation of the bacterium strain Streptomyces sp. CNH-189, which was isolated from marine sediment. The planar structures of compounds 1−4 and 10 were elucidated by interpretation of MS, UV, and NMR spectroscopic data. The relative configurations of compounds 1−4 were determined via analysis of nuclear Overhauser effect (NOE) spectroscopic data, after which their absolute configurations were established by comparing the experimental electronic circular dichroism (ECD) spectra of compounds 1−4 to those of previously reported possible enantiomer models and DP4 calculations. Compound 3 displayed strong antibacterial activities against Bacillus subtilis, Kocuria rhizophila, and Staphylococcus aureus, with MIC values of 1, 2, and 2 μg/mL, respectively, whereas compound 1 exhibited weak antibacterial effects on these three strains, with a 16−32 μg/mL MIC value range.  相似文献   
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