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51.
This study was conducted to gain insight into the characteristics of algal blooms in relation to the marine environment of
Gamak Bay. From the first known occurrence of algal blooms in 1984 until 2006, 23 causal species have been identified, the
most common ones being Prorocentrum sp., Cochlodinium polykrikoides, Chaetoceros sp., Skeletonema costatum, and Heterosigma akashiwo. A principal component analysis indicated that blooms of these species develop under different conditions in terms of water
temperature, salinity, precipitation, and insolation. Field data showed Cochlodinium polykrikoides to be favored by high temperatures and to be euryhaline, whereas Skeletonema costatum appeared to be eurythermal and euryhaline. Prorocentrum sp. and Chaetoceros sp. appeared to be stenothermal and stenohaline. Finally, Heterosigma akashiwo appeared at the lowest temperature and highest salinity of the five species and was classified here as stenothermal and stenohaline. 相似文献
52.
53.
Toxicity of Lavandula angustifolia oil constituents and spray formulations to insecticide‐susceptible and pyrethroid‐resistant Plutella xylostella and its endoparasitoid Cotesia glomerata
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54.
So Young Kim Myoung-Sook Shin Geum Jin Kim Hyukbean Kwon Myong Jin Lee Ah-Reum Han Joo-Won Nam Chan-Hun Jung Ki Sung Kang Hyukjae Choi 《Marine drugs》2021,19(8)
The epithelial–mesenchymal transition (EMT) of cancer cells is a crucial process in cancer cell metastasis. An Aquimarina sp. MC085 extract was found to inhibit A549 human lung cancer cell invasion, and caprolactin C (1), a new natural product, α-amino-ε-caprolactam linked to 3-methyl butanoic acid, was purified through bioactivity-guided isolation of the extract. Furthermore, its enantiomeric compound, ent-caprolactin C (2), was synthesized. Both 1 and 2 inhibited the invasion and γ-irradiation-induced migration of A549 cells. In transforming growth factor-β (TGF-β)-treated A549 cells, 2 inhibited the phosphorylation of Smad2/3 and suppressed the EMT cell marker proteins (N-cadherin, β-catenin, and vimentin), as well as the related messenger ribonucleic acid expression (N-cadherin, matrix metalloproteinase-9, Snail, and vimentin), while compound 1 did not suppress Smad2/3 phosphorylation and the expression of EMT cell markers. Therefore, compound 2 could be a potential candidate for antimetastatic agent development, because it suppresses TGF-β-induced EMT. 相似文献
55.
While much is known about the metabolism of exogenous nutrients such as glucose, lactate, pyruvate, amino acids by oocytes and pre-implantation mammalian embryos, the role of endogenous stores, particularly lipid, has been largely overlooked. The presence of lipid within oocytes and early embryos has been long known, and comparisons between species indicate that the amounts and types of lipid present vary considerably. Large amounts of intracellular lipid can compromise the success of cryopreservation and the removal of such lipid has been the subject of considerable effort. In this review, we present evidence that strongly suggests a metabolic role for lipid, specifically with regard to energy provision, in the late-stage oocyte and the pre-implantation embryo. We focus initially on oxygen consumption as a global indicator of metabolic activity, before reviewing different approaches that either have been designed to investigate directly, or have revealed indirectly the role of endogenous lipid in energy generation. These fall under five headings: (i) fatty acid oxidation; (ii) inhibition of triglyceride oxidation; (iii) culture in the absence of exogenous substrates; (iv) cytoplasmic organization; and (v) delipidation. On the basis of the data derived from these studies, we conclude that there is strong evidence for the utilization of endogenous lipid as an energy substrate by oocytes and early embryos. 相似文献
56.
Hye Kwon Kim Jeong Sun Yang Hyoung Joon Moon Seong Jun Park Yuzi Luo Chul Seung Lee Dae Sub Song Bo Kyu Kang Soo Kyung Ann Chan Hyuk Jun Bong Kyun Park 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(2):121-130
The 23 open reading frame (ORF) 5 sequences of Korean type II porcine reproductive and respiratory syndrome virus (PRRSV) were collected from viremic sera from the (modified live vaccine) MLV-vaccinating and non-vaccinating farms from 2007 to 2008. The samples were phylogenetically analyzed with previous ORF5 sequences, including type I Korean PRRSV, and previously reported or collected sequences from 1997 to 2008. A MN184-like subgroup of type II Korean PRRSV was newly identified in the viremic sera collected from 2007 to 2008. And of the type I PRRSVs, one subgroup had 87.2~88.9% similarity with the Lelystad virus, showing a close relationship with the 27~2003 strain of Spain. The maximum parsimony tree of type II PRRSV from 1997 to 2008 showed that they had evolved to four lineages, subgroups 1, 2, 3 and 4. Most of the recently collected type II PRRSVs belonged to subgroup 4 (48%). The region of three B-cell epitopes and two T-cell epitopes of ORF5 amino acids sequences was considerably different from the MLV in subgroups 3 and 4. In conclusion, the existence of type I PRRSV, which was genetically different from Lelystad virus (Prototype of type I PRRSV), and heterologous type II PRRSVs of viremic pigs detected even in the MLV-vaccinating farms indicated the need for new vaccine approaches for the control of PRRSV in Korea. 相似文献
57.
Dae Sub Song Youn Jeong Lee Ok Mi Jeong Yong Joo Kim Chan Hee Park Jung Eun Yoo Woo Jin Jeon Jun Hun Kwon Gun Woo Ha Bo Kyu Kang Chul Seung Lee Hye Kwon Kim Byeong Yeal Jung Jae Hong Kim Jin Sik Oh 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(4):323-329
Active serologic surveillance is necessary to control the spread of the avian influenza virus (AIV). In this study, we evaluated a commercially-available cELISA in terms of its ability to detect AIV antibodies in the sera of 3,358 animals from twelve species. cELISA detected antibodies against reference H1- through H15-subtype AIV strains without cross reactivity. Furthermore, the cELISA was able to detect antibodies produced following a challenge of the AIV H9N2 subtype in chickens, or following vaccination of the AIV H9 or H5 subtypes in chickens, ducks and geese. Next, we tested the sensitivity and specificity of the cELISA with sera from twelve different animal species, and compared these results with those obtained by the hemagglutination-inhibition (HI) test, the "gold standard" in AIV sera surveillance, a second commercially-available cELISA (IZS ELISA), or the agar gel precipitation (AGP) test. Compared with the HI test, the sensitivities and specificities of cELISA were 95% and 96% in chicken, 86% and 88% in duck, 97% and 100% in turkey, 100% and 87% in goose, and 91% and 97% in swine, respectively. The sensitivities and specificities of the cELISA in this study were higher than those of IZS ELISA for the duck, turkey, goose, and grey partridge sera samples. The results of AGP test against duck and turkey sera also showed significant correlation with the results of cELISA (R-value >0.9). In terms of flock sensitivity, the cELISA correlated better with the HI test than with commercially-available indirect ELISAs, with 100% flock sensitivity. 相似文献
58.
Hee Ock Boo Jeong Hun Park Hag Hyun Kim Soo Jeong Kwon Sun Hee Woo 《Journal of Crop Science and Biotechnology》2018,21(5):507-514
This study was conducted to investigate cytotoxic effect, phenolic content, DPPH, ABTS radical scavenging rate and nitrite scavenging rate from different solvent fractions of Codonopsis lanceolate root. At all extracts concentration, the cytotoxic effect on different fractions against human cancer cells was higher in n-hexane and butyl alcohol fractions than in the other fractions. The IC50 value on HeLa cell showed the lowest by 62.70 μg.mL-1 on n-hexane fraction, and exhibited the values of butyl alcohol fraction 341.36 μg.mL-1, methylene chloride 598.33 μg.mL-1, ethyl acetate fraction 860.44 μg.mL-1, DW fraction 2896.82 μg.mL-1. Total polyphenol content on different solvent fractions varied from 102.43 to 153.52 mg.g-1, and that of ethyl acetate fraction showed the highest amount. The DPPH and ABTS radical scavenging activity showed that the increase was proportional to the concentration, and the scavenging activity also showed the highest in ethyl acetate fraction. The nitrite scavenging activity of each fraction at pH 1.2 was in the order of EA > BA > MC > n-H > DW, and the lower the acidity, the higher nitrite scavenging activity, and there was no distinct detection of nitrite scavenging effects of the pH range 6.0. The results of this study suggested that the extract of Codonopsis lanceolate root may assist in the potential biological activities, and it was found that the activity was different depending on the organic solvent fraction and the water fraction. 相似文献
59.
Dong-Gun Kim Jaihyunk Ryu Min-Kyu Lee Jung Min Kim Joon-Woo Ahn Jin-Baek Kim Si-Yong Kang Chang-Hyu Bae Soon-Jae Kwon 《Journal of Crop Science and Biotechnology》2018,21(3):229-239
Kenaf is an economically important crop that contains various functional compounds. The objective of this study was to evaluate the nutritional properties of leaves, stem bark, flowers, and seeds collected from three mutant kenaf cultivars (Jangdae, Baekma, and Jeokbong) and two original cultivars (Jinju and C14). For all analyzed tissues, there were no significant differences in the proximate compositions (moisture, crude protein, crude fiber, crude fat, ash, and nitrogen-free extract) among the tested genotypes, except for the leaf crude protein content, which was highest in Jinju plants. Of the tested minerals, potassium and calcium were the most abundant in all tissues. Additionally, we detected significant differences in the mineral contents (e.g., calcium, phosphorus, potassium, magnesium, zinc, and iron) of various tissues in all cultivars. Proline and phenylalanine were the major amino acids detected in leaves, and the highest total amino acid (TAA) and essential amino acid (EAA) contents were observed in Jinju plants. The TAA and EAA contents were lower in stem bark than in the other tissues, except in Baekma plants, in which the lowest levels were observed in flowers. Moreover, the TAA and EAA contents were approximately 20 times lower in white flowers (Baekma) than in ivory flowers. Furthermore, the highest TAA and EAA concentrations were observed in Jangdae seeds. These results may be useful for identifying the optimal cultivar and tissues for use in food products. 相似文献
60.
Effect of catheter size and injection rate of contrast agent on enhancement and image quality for triple‐phase helical computed tomography of the liver in small dogs
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Sang‐Kwon Lee Dahae Lee Dongeun Kim Ahyoung Cha Jihye Choi 《Veterinary radiology & ultrasound》2017,58(6):664-670
Rapid contrast injection is recommended for triple‐phase helical computed tomography (CT) of the liver. However, a large‐gauge catheter is needed for faster contrast injection and this is not practical for small breed dogs or cats. The purpose of this crossover group study was to evaluate applicability of a lower injection rate with a small‐gauge (G) catheter for triple‐phase hepatic CT in small dogs. Triple‐phase CT images were acquired for six beagle dogs using three protocols: an injection rate of 1.5 ml/s with a 24 G catheter, 3.0 ml/s with a 22 G catheter, and 4.5 ml/s with a 20 G catheter. Enhancement of the aorta, portal vein, and hepatic parenchyma was measured in each phase (arterial, portal, and delayed) and image quality was scored subjectively by two observers. Injection duration, time to scan delay, and time to peak enhancement were also recorded. Contrast injection duration decreased with a higher injection rate (n = 6, P ≤ 0.01), but time to peak enhancement and time to scan delay were not significantly affected by injection rates and catheter sizes. Contrast injection rate did not significantly affect aortic, portal, and hepatic enhancement. In addition, separation between each phase and quality of images was subjectively scored as good regardless of injection rate. Findings from the current study supported using an injection rate of 1.5 ml/s with a catheter size of 24 G for triple‐phase hepatic CT in small dogs (weight < 12 kg). 相似文献