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101.
Proliferation and collapse of subcuticular hyphae of Venturia nashicola race 1 were studied ultrastructurally, after inoculation of susceptible Japanese pear cv. Kousui, resistant Japanese pear
cv. Kinchaku, resistant Asian pear strain Mamenashi 12 and nonhost European pear cv. Flemish Beauty leaves, to understand
the nature of the resistance mechanism. After cuticle penetration by the pathogen, the hyphae were observed at lower frequency
in epidermal pectin layers and middle lamellae of leaves of the three resistant plants than in those of susceptible ones.
This result suggested that fungal growth was suppressed in the incompatible interaction between pear and V. nashicola race 1. In the pectin layers of all inoculated plants, some hyphae had modifications such as breaks in the plasmalemma with
plasmolysis, necrotic cytoplasm and degraded cell walls. More hyphae had collapsed in the leaves of the three resistant plants
than in those of the susceptible cv. Kousui. In collapsed hyphae, the polymerized cell walls broke into numerous fibrous and
amorphous pieces, showing that the scab resistance might be associated with cell wall-degrading enzymes from pear plants. 相似文献
102.
The present study demonstrates the effects of different muscle types and chiller ageing periods on the chemical composition, meat quality parameters, sensory characteristics and volatile compounds of Karean native cattle beed. Longissimus dorsi (LD) and Semitendinosus (ST) muscles aged for 7 days and 28 days were used. Moisture, cooking loss, total collagen and Warner‐Bratzler shear force (WBSF) values for the ST were higher than the LD muscle regardless of ageing period (P < 0.05). The LD muscle had higher intramuscular fat (IMF) (P < 0.05). Ageing for 28 days decreased WBSF values whereas it increased thiobarbituric acid of both muscles. Moreover, tenderness, juiciness and flavor scores were significantly higher for the LD muscle at both ageing periods. Increased ageing time improved tenderness of both muscles, and increased juiciness of the LD muscle, whereas there was decreased flavor score of ST muscle (P < 0.05). The majority of the volatile compounds formed from the oxidation of lipids showed differences between the two muscles. Ageing for 28 days increased in the amounts of many volatile compounds; however, the amounts of some important volatile compounds were decreased. These results clearly demonstrate that muscle type and ageing have a potential effect on meat quality, sensory characteristics and volatile profile. 相似文献
103.
104.
Yuk HJ Curtis-Long MJ Ryu HW Jang KC Seo WD Kim JY Kang KY Park KH 《Journal of agricultural and food chemistry》2011,59(23):12683-12690
Soybean leaves are eaten as seasonal edible greens in Korea. Analysis of the ethyl acetate extract of these leaves showed that it exhibited potent and selective neuraminidase inhibition, which began at the R3 stage and peaked at R7. Ten pterocarpans, including the new 6a-hydroxypterocarpan 10, were isolated from soybean leaves and their inhibition activities tested against a range of glycosidases. The relationship between structure and enzyme inhibition was investigated: 6a-hydroxypterocarpans exhibited much higher inhibition against neuraminidase (IC(50) = 2.4-89.4 μM) than α-glucosidase (IC(50) = 90.4-?>100 μM). Glyceollin VII (7) displayed 40-fold greater activity (IC(50) = 2.4 μM) against neuraminidase than α-glucosidase (IC(50) = 90.4 μM). On the other hand, coumestanes (1-3) were good α-glucosidase inhibitors (IC(50) = 6.0-42.6 μM). In kinetic analysis, the most potent neuraminidase inhibitors (5-10) were noncompetitive. HPLC analysis indicated that most pterocarpan synthesis began from the R3 stage, and a rapid change of pterocarpan concentrations was observed between the R4 and R7 stages. 相似文献
105.
Park ES Seong JK Yi SJ Kim JS Lee HS Lee IS Yoon YS 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(7):639-646
This study was carried out to investigate the changes of orexin-A (OXA) and neuropeptide Y (NPY) expression in the hypothalamus of the obese and lean Zucker Diabetic Fatty (ZDF) rats which have a missense mutation in the leptin receptor gene. The mean body weights (MBW) between the obese and lean ZDF rats were significantly different at 28 and 70 postnatal days. However, at 14 postnatal day, there was no significant difference in the MBW between the obese and lean ZDF rats in both male and female. The OXA immunoreactivities were not significantly different between the obese and lean ZDF rats in both sexes at 14, 28, and 70 postnatal days, respectively. The NPY immunoreactivity was higher in the obese than in the lean ZDF rats in both male and female at 28 and 70 postnatal days, whereas there was no significant difference between the obese and lean ZDF rats at 14 postnatal day. These results indicate that both OXA and NPY might halt their roles for food intake in the obese phenotype of the male and female ZDF rats in the preweaning period of 14 postnatal day, whereas NPY might play a main role in the obesity of these rats in the weaning period of 28 and 70 postnatal days. 相似文献
106.
Jin-Kyu Rhee Ok Kyu Park Aeju Lee Dae Hyeok Yang Kyeongsoon Park 《Marine drugs》2014,12(12):6038-6057
Theranostics is an integrated nanosystem that combines therapeutics with diagnostics in attempt to develop new personalized treatments with enhanced therapeutic efficacy and safety. As a promising therapeutic paradigm with cutting-edge technologies, theranostic agents are able to simultaneously deliver therapeutic drugs and diagnostic imaging agents and also monitor the response to therapy. Polymeric nanosystems have been intensively explored for biomedical applications to diagnose and treat various cancers. In recent years, glycol chitosan-based nanoagents have been developed as dual-purpose materials for simultaneous diagnosis and therapy. They have shown great potential in cancer therapies, such as chemotherapeutics and nucleic acid and photodynamic therapies. In this review, we summarize the recent progress and potential applications of glycol chitosan-based fluorescent theranostic nanoagents for cancer treatments and discuss their possible underlying mechanisms. 相似文献
107.
Chang Hoon Lee Ui Gum Kang Ki Do Park Do Kyoung Lee Pil Joo Kim 《Journal of plant nutrition》2013,36(8):1496-1506
ABSTRACT Long-term fertilization tests evaluated rice (Oryza sativa) productivity in relation to application of nitrogen (N)-phosphorus (P)-potassium (K) (120-34.9-66.7 kg ha? 1, respectively) during 1967–1972 and N-P-K (150-43.7-83.3 kg ha? 1, respectively) during 1973–2000. The comparison treatments (NP, PK, and NK) and the control (not fertilized) were selected for calculating nutrient efficiency. Rice grain yield increased at a 17.78 kg ha? 1 yr? 1 in the control, mainly due to development of improved cultivars. Phosphorus management was found to be important for indigenous fertility and rice productivity in this paddy soil. Yield increased significantly with P fertilization. Without N fertilization (PK), rice productivity increased 56.85 kg ha? 1 yr? 1 from 62% of NPK at the initial stage to 74% after passing 34 years, which might be affected by increasing biological N fixation with P accumulation in soil. In NK treatment, rice yield increased at a relatively low rate (37.82 kg hr? 1 yr? 1) from the same rice productivity with that of NPK in 1967 to 91% after 34 years. In comparison, yield increased at a high rate (62.82 kg hr? 1 yr? 1) without K fertilization (NP) from ca. 90% of NPK and might exceed the yield of NPK after 64 years of long-term fertilization. Therefore, K fertilization level might be readjusted after long-term fertilizing in paddy soil. 相似文献
108.
Association of Obesity with Serum Leptin,Adiponectin, and Serotonin and Gut Microflora in Beagle Dogs 下载免费PDF全文
H.‐J. Park S.‐E. Lee H.‐B. Kim R.E. Isaacson K.‐W. Seo K.‐H. Song 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(1):43-50
Background
Serotonin (5‐hydroxytryptamine, 5HT) is involved in hypothalamic regulation of energy consumption. Also, the gut microbiome can influence neuronal signaling to the brain through vagal afferent neurons. Therefore, serotonin concentrations in the central nervous system and the composition of the microbiota can be related to obesity.Objective
To examine adipokine, and, serotonin concentrations, and the gut microbiota in lean dogs and dogs with experimentally induced obesity.Animals
Fourteen healthy Beagle dogs were used in this study.Methods
Seven Beagle dogs in the obese group were fed commercial food ad libitum, over a period of 6 months to increase their weight and seven Beagle dogs in lean group were fed a restricted amount of the same diet to maintain optimal body condition over a period of 6 months. Peripheral leptin, adiponectin, 5HT, and cerebrospinal fluid (CSF‐5HT) levels were measured by ELISA. Fecal samples were collected in lean and obese groups 6 months after obesity was induced. Targeted pyrosequencing of the 16S rRNA gene was performed using a Genome Sequencer FLX plus system.Results
Leptin concentrations were higher in the obese group (1.98 ± 1.00) compared to those of the lean group (1.12 ± 0.07, P = .025). Adiponectin and 5‐hydroytryptamine of cerebrospinal fluid (CSF‐5HT) concentrations were higher in the lean group (27.1 ± 7.28) than in the obese group (14.4 ± 5.40, P = .018). Analysis of the microbiome revealed that the diversity of the microbial community was lower in the obese group. Microbes from the phylum Firmicutes (85%) were predominant group in the gut microbiota of lean dogs. However, bacteria from the phylum Proteobacteria (76%) were the predominant group in the gut microbiota of dogs in the obese group.Conclusions and Clinical Importance
Decreased 5HT levels in obese group might increase the risk of obesity because of increased appetite. Microflora enriched with gram‐negative might be related with chronic inflammation status in obese dogs. 相似文献109.
Park BS Kim JR Lee SE Kim KS Takeoka GR Ahn YJ Kim JH 《Journal of agricultural and food chemistry》2005,53(4):1152-1157
The growth-inhibiting activity of anthraquinone-2-carboxylic acid and lapachol identified in the inner bark of taheebo, Tabebuia impetiginosa, toward 10 human intestinal bacteria was evaluated by using a paper disk diffusion bioassay and compared to those of seven lapachol congeners (1,4-naphthoquinone, naphthazarin, menadione, lawsone, plumbagin, juglone, and dichlone) as well as two commercially available antibiotics, chloramphenicol and tetracycline. Anthraquinone-2-carboxylic acid exhibited very strong growth inhibition of Clostridium paraputrificum at 1 microg/disk while 100 microg/disk of lapachol was needed for moderate growth inhibition of the same organism. These two isolates exhibited weak inhibition of Clostridium perfringens and Escherichia coli at 100 microg/disk while no adverse effects were observed on the growth of Bifidobacterium adolescentis, Bifidobacterium bifidum, Bifidobacterium infantis, Lactobacillus acidophilus, and Lactobacillus casei at 1000 microg/disk. Structure-activity relationships indicate that a methyl group in the C-2 position of 1,4-naphthoquinone derivatives might play an important role in antibacterial activity. 相似文献
110.
Seong Bin Park Kyoung Kwon In Seok Cha Ho Bin Jang Seong Won Nho Fernand F. Fagutao Young Kyu Kim Jong Earn Yu Tae Sung Jung 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(1):163-166
A multiplex PCR protocol was established to simultaneously detect major bacterial pathogens in olive flounder (Paralichthys olivaceus) including Edwardsiella (E.) tarda, Streptococcus (S.) parauberis, and S. iniae. The PCR assay was able to detect 0.01 ng of E. tarda, 0.1 ng of S. parauberis, and 1 ng of S. iniae genomic DNA. Furthermore, this technique was found to have high specificity when tested with related bacterial species. This method represents a cheaper, faster, and reliable alternative for identifying major bacterial pathogens in olive flounder, the most important farmed fish in Korea. 相似文献