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71.
Hemocytes of the last larva of the Japanese rhinoceros beetle A. dichotoma (Linnaeus) (Coleoptera: Scarabaeidae) were classified as granulocytes, plasmatocytes, oenocytoids, spherulocytes, prohemocytes, and adipohemocytes. Among these cell types, only the granulocytes became immunologically activated with obvious morphological changes, displaying large amoeba-like, lobopodia-like, and fan-like structures. In addition, their cytoplasmic granules became larger and greatly increased in number. To explore whether these granules could be immunologically generated as phagosomes, total hemocytes were stained with LysoTracker. Greater than 90% of the granulocytes retained the LysoTracker dye at 4 h post-bacterial infection. In flow cytometry analysis, the red fluorescent signal was highly increased at 4 h post-bacterial infection (60.36%) compared to controls (5.08%), as was confirmed by fluorescent microscopy. After 12 h post-infection, these signals returned to basal levels. The uptake of pathogens by granulocytes rapidly triggered the translocation of the microtubule-associated protein 1 light chain 3 alpha (LC3) to the phagosome, which may result in enhanced pathogen killing. 相似文献
72.
Jiu-Xiang Xie Gong-Hua Lin Cui-Xia Liu Chuan-Hua Yang Xiao-Gong Deng Xue-Feng Cui Bang Li Tong-Zuo Zhang Jian-Ping Su 《Acta theriologica》2014,59(2):337-345
Subterranean herbivores affect the plant community by plant consumption and burrowing activities. However, diet selection of subterranean herbivores has not been studied in detail in complex natural fields, mainly for lack of an accurate method to determine diet species, frequency, and biomass. Plateau zokors' (Eospalax baileyi) caching habit for the long inclement winter makes it possible to solve this problem. We studied the diet composition and biomass in caches and vicinity of plateau zokors' burrow systems. We found that plateau zokors are dietary generalist but show a significant selection among the available food items, plant parts, functional groups, organ types, and habitats. These results suggested that plateau zokors strictly selected their diet and were able to adjust their foraging strategy according to the different conditions of food abundance and quality. Plateau zokors' selective foraging can directly reduce the proportion of toxicity forbs; plateau zokors can be recognized as an important element to influence the alpine meadow plant community and cattle husbandry. 相似文献
73.
Phi Hung Nguyen Thi Van Thu Le Hu Won Kang Jooyoung Chae Sang Kyum Kim Kwang-iI Kwon Dae Bang Seo Sang Jun Lee Won Keun Oh 《Bioorganic & medicinal chemistry letters》2010,20(14):4128-4131
AMP-activated protein kinase (AMPK) is a potential therapeutic target for the treatment of metabolic syndrome including obesity and type-2 diabetes. As part of an ongoing search for new AMPK activators from plants, this study found that the total extract of Myristica fragrans (nutmeg) activated the AMPK enzyme in differentiated C2C12 cells. As active constituents, seven 2,5-bis-aryl-3,4-dimethyltetrahydrofuran lignans, tetrahydrofuroguaiacin B (1), saucernetindiol (2), verrucosin (3), nectandrin B (4), nectandrin A (5), fragransin C1 (6), and galbacin (7) were isolated from this extract. Among the isolates, compounds 1, 4, and 5 at 5 μM produced strong AMPK stimulation in differentiated C2C12 cells. In addition, the preventive effect of a tetrahydrofuran mixture (THF) on weight gain in a diet-induced animal model was further examined. These results suggest that nutmeg and its active constituents can be used not only for the development of agents to treat obesity and possibly type-2 diabetes but may also be beneficial for other metabolic disorders. 相似文献
74.
Zhao WG Chung JW Cho YI Rha WH Lee GA Ma KH Han SH Bang KH Park CB Kim SM Park YJ 《Comptes rendus biologies》2010,333(11-12):793-800
This study was conducted to assess the genetic diversity and population structure of 139 Lycium chinense accessions using 18 simple sequence repeat (SSR) markers. In total, 108 alleles were detected. The number of alleles per marker locus ranged from two to 17, with an average of six. The gene diversity and polymorphism information content value averaged 0.3792 and 0.3296, with ranges of 0.0793 to 0.8023 and 0.0775 to 0.7734, respectively. The average heterozygosity was 0.4394. The model-based structure analysis revealed the presence of three subpopulations, which was consistent with clustering based on genetic distance. An AMOVA analysis showed that the between-population component of genetic variance was less than 15.3%, in contrast to 84.7% for the within-population component. The overall FST value was 0.1178, indicating a moderate differentiation among groups. The results could be used for future L. chinense allele mining, association mapping, gene cloning, germplasm conservation, and designing effective breeding programs. 相似文献
75.
Hai‐Qing Yu Chun Zhang Chun‐Bang Ding Hai‐Qin Zhang Yong‐Hong Zhou 《Nordic Journal of Botany》2010,28(2):206-211
The genomic constitutions of Roegneria alashanica, R. elytrigioides, R. magnicaespes and R. grandis were studied using GISH. DNA of Pseudoroegneria spicata (St), P. libanotica (St), P. stipifolia (St), R. ciliaris (StY), Lopophyllum elongatum (Ee), Agropyron cristatum (P) and Hordeum bogdanii (H) were used for probing, respectively. The results indicated that: 1) R. alashanica and R. magnicaespes contained one St genome, the other genome was unidentified, however, it was not an E, P, H or Y genome; 2) R. elytrigioides contained two St genomes and should on this basis be included in Pseudoroegneria; 3) R. grandis contained an St and an Stg genome. The Stg genome is suggested to be a modified form of the St genome of Pseudoroegneria and to be homoeologous with the Y genome. It might be an intermediate type between the St and Y genomes. Therefore, R. elytrigioides should be treated as Pseudoroegneriaelytrigioides.Roegneria alashanica, R. magnicaespes and R. grandis does apparently not belong in the genus Roegneria but further studies are needed to establish their correct taxonomic position. 相似文献
76.
So-Young Bang Tae-Un Han Chan-Bum Choi Yoon-Kyoung Sung Sang-Cheol Bae Changwon Kang 《Arthritis research & therapy》2010,12(3):R115
Introduction
Anti-cyclic citrullinated peptide autoantibodies (anti-CCP) are the most specific serologic marker for rheumatoid arthritis (RA). Genetic polymorphisms in a citrullinating (or deiminating) enzyme, peptidyl arginine deiminase type IV (PADI4) have been reproducibly associated with RA susceptibility in several populations. We investigated whether PADI4 polymorphisms contribute to anti-CCP-negative as well as -positive RA, whether they influence disease severity (erosive joint status), and whether they interact with two major risk factors for RA, Human Leukocyte Antigen-DRB1 (HLA-DRB1) shared epitope (SE) alleles and smoking, depending on anti-CCP and erosive joint status. 相似文献77.
Inja Lim Jihyun Yun Jung‐Ha Kim Young‐Ku Kang Nari Kim Jin Han Hyoweon Bang Jae‐Hong Ko 《Birth defects research. Part B, Developmental and reproductive toxicology》2010,89(3):201-206
BACKGROUND: This study was conducted to evaluate the occurrence and fate of fetal lumbar rib induced by Scutellariae radix (SR) in rats. METHODS: Water extracts of SR were orally administered to pregnant rats from day 7 to day 17 of gestation at a dose of 186 mg/kg/day, equivalent to 25 g/kg of starting material, representing a 100‐fold increase over typical human intake level. RESULTS: The incidence of fetal lumbar rib in the SR‐treated group was increased on gestational day 20 and then decreased on postnatal day 50. The weight of fetuses in the SR‐treated group tended to be less than that in the control group. Alkaline phosphatase in SR‐treated dams was increased on gestational day 20, but was decreased on postnatal day 50. There were no significant differences between the vehicle control and SR‐treated groups in maternal body weight, embryological, histopathological, hematological, and serum biochemical changes. CONCLUSIONS: The present data suggest that the appearance of lumbar rib induced by SR is a transient fetal variation rather than teratogenicity or maternal toxicity. Birth Defects Res (Part B) 89:201–206, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
78.
Qihai Zhou Fuwen Wei Chengming Huang Ming Li Baoping Ren Bang Luo 《International journal of primatology》2007,28(3):657-671
Activity patterns and time budgets are 2 important aspects of animal behavior that researchers use to investigate ecological influences on individual behavior. We collected data on activity patterns and time budgets in 1 group of François’ langurs (Trachypithecus francoisi) from August 2003 to July 2004 in the Nonggang Nature Reserve, Guangxi Province, China, via instantaneous scan sampling method with 15-min intervals. The diurnal activity pattern of François’ langurs showed morning and afternoon feeding peaks, with a midday resting peak. Seasonal change was apparent in the activity pattern: 2 significant feeding peaks occurred in the dry season and only 1 significant feeding peak in the rainy season. The group spent an average of 51.5% of the daytime resting. Feeding and moving accounted on average for 23.1% and 17.3% of the activity budget, respectively. Subjects spent little time on social activities, averaging 2% for grooming and 5.5% for playing. Their time budgets showed significant seasonal variation: they spent a greater proportion of time on feeding and less time on resting and grooming in the dry season than in the rainy season. They also differed among different sex-age classes: immatures spent more time playing, whereas adults devoted more time to resting, feeding, and grooming. Correlations between time budgets and food items or food availability clearly indicated that François’ langurs might adopt an energy-maximizing strategy when preferred foods were scarce in the dry season. 相似文献
79.
Kim YK Oh SY Jeon SG Park HW Lee SY Chun EY Bang B Lee HS Oh MH Kim YS Kim JH Gho YS Cho SH Min KU Kim YY Zhu Z 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(8):5375-5382
Allergic asthma is characterized by airway inflammation initiated by adaptive immune responses to aeroallergens. Recent data suggest that severe asthma may be a different form of asthma rather than an increase in asthma symptoms and that innate immune responses to LPS can modulate adaptive immune responses to allergens. In this study, we evaluated the hypothesis that airway exposure to different doses of LPS induces different form of asthma. Our study showed that neutrophilic inflammation and IFN-gamma expression were higher in induced sputum from severe asthma patients than from mild to moderate asthmatics. Animal experiments indicated that allergen sensitization with low-dose LPS (0.1 microg) induced type 2 asthma phenotypes, i.e., airway hyperresponsiveness, eosinophilic inflammation, and allergen-specific IgE up-regulation. In contrast, allergen sensitization with high-dose LPS (10 microg) induced asthma phenotypes, i.e., airway hyperresponsiveness and noneosinophilic inflammation that were not developed in IFN-gamma-deficient mice, but unaffected in the absence of IL-4. During the allergen sensitization period, TNF-alpha expression was found to be enhanced by both low- and high-dose LPS, whereas IL-12 expression was only enhanced by high-dose LPS. Interestingly, the asthma phenotypes induced by low-dose LPS, but not by high-dose LPS, were completely inhibited in TNF-alpha receptor-deficient mice, whereas the asthma phenotypes induced by high-dose LPS were abolished in the homozygous null mutation of the STAT4 gene. These findings suggest that airway exposure levels of LPS induces different forms of asthma that are type 1 and type 2 asthma phenotypes by high and low LPS levels, respectively. 相似文献
80.
Kang SH Kim GR Seong M Baek SH Seol JH Bang OS Ovaa H Tatsumi K Komatsu M Tanaka K Chung CH 《The Journal of biological chemistry》2007,282(8):5256-5262
Ubiquitin-fold modifier 1 (Ufm1) is a recently identified new ubiquitin-like protein, whose tertiary structure displays a striking resemblance to ubiquitin. Similar to ubiquitin, it has a Gly residue conserved across species at the C-terminal region with extensions of various amino acid sequences that need to be processed in vivo prior to conjugation to target proteins. Here we report the isolation, cloning, and characterization of two novel mouse Ufm1-specific proteases, named UfSP1 and UfSP2. UfSP1 and UfSP2 are composed of 217 and 461 amino acids, respectively, and they have no sequence homology with previously known proteases. UfSP2 is present in most, if not all, of multicellular organisms including plant, nematode, fly, and mammal, whereas UfSP1 could not be found in plant and nematode upon data base search. UfSP1 and UfSP2 cleaved the C-terminal extension of Ufm1 but not that of ubiquitin or other ubiquitin-like proteins, such as SUMO-1 and ISG15. Both were also capable of releasing Ufm1 from Ufm1-conjugated cellular proteins. They were sensitive to inhibition by sulfhydryl-blocking agents, such as N-ethylmaleimide, and their active site Cys could be labeled with Ufm1-vinylmethylester. Moreover, replacement of the conserved Cys residue by Ser resulted in a complete loss of the UfSP1 and UfSP2 activities. These results indicate that UfSP1 and UfSP2 are novel thiol proteases that specifically process the C terminus of Ufm1. 相似文献