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161.
Chul-Hong Park Byung Yeoup Chung Seung Sik Lee Hyoung-Woo Bai Jae Young Cho Cheorun Jo Tae Hoon Kim 《Bioorganic & medicinal chemistry letters》2013,23(4):1099-1103
Radiolytic transformation of the isoflavonoid rotenone (1) with γ-irradiation afforded two new degraded products, rotenoisins A (2) and (3). The structures of the two new rotenone derivatives were elucidated on the basis of spectroscopic methods. The new products 2 and 3 exhibited significantly enhanced inhibitory activities against pancreatic lipase and adipocyte differentiation in 3T3-L1 cells when compared to parent rotenone. 相似文献
162.
Seong Rim Byeon Hyunjin Vincent Kim Mijin Jeon Young Gil Ahn Maeng Sup Kim Jae Yang Kong Hye Yun Kim Young Soo Kim Dong Jin Kim 《Bioorganic & medicinal chemistry letters》2013,23(11):3467-3469
Alzheimer’s disease drug discovery regarding exploration into the molecules and processes has focused on the intrinsic causes of the brain disorder correlated with the accumulation of amyloid-β. An anti-amyloidogenic bis-styrylbenzene derivative, KMS80013, showed excellent oral bioavailability (F = 46.2%), facilitated brain penetration (26%, iv) in mouse and target specific in vivo efficacy in acute AD mouse model attenuating the cognitive deficiency in Y-maze test. Acute toxicity (LD50 >2000 mg/kg) and hERG channel inhibition (14% at 10 μM) results indicated safety of KMS80013. 相似文献
163.
Li Zhu Tsuneyuki Tatsuke Hiroaki Mon Zhiqing Li Jian Xu Jae Man Lee Takahiro Kusakabe 《Insect biochemistry and molecular biology》2013,43(8):664-674
The Tudor-sn protein, which contains four staphylococcal nuclease domains and a Tudor domain, is a ubiquitous protein found in almost all organisms. It has been reported that Tudor-sn in mammals participates in various cellular pathways involved in gene regulation, cell growth, and development. In insects, we have previously identified a Tudor-sn ortholog in the silkworm, Bombyx mori, and detected its interactions between with Argonaute proteins. The role of Tudor-sn in silkworm, however, still remains largely unknown. In this study, we demonstrated that silkworm Tudor-sn is a stress granule (SG) protein, and determined its interactions with other SG proteins using Bimolecular Fluorescence Complementation assay and Insect Two-Hybrid method. Depletions of Argonaute proteins and SG-marker protein Tia1 by RNAi impaired the involvement of Tudor-sn in the SG formation. Protein domain deletion analysis of Tudor-sn demonstrated that SN2 is the key domain required for the aggregation of Tudor-sn in SGs. 相似文献
164.
以不同抗白粉病的苦瓜品系幼苗为材料,对它们的叶片及上下表皮厚度、栅栏组织及海绵组织厚度、叶片结构紧密度及疏松度、蜡质含量、比叶重、气孔及茸毛密度等叶片结构进行观察比较,探讨苦瓜白粉病抗性与其主要叶片结构指标的关系。结果显示:(1)抗病苦瓜品系叶片的蜡质含量显著高于感病品系,与病情指数呈显著负相关关系,蜡质层是其抵抗和延迟病原菌侵入的一个有力结构屏障。(2)感病品系叶片的气孔和叶背面茸毛数量显著多于抗病品系,且叶背面的气孔及茸毛密度与病情指数呈显著正相关关系,即气孔和茸毛越少越抗病。(3)抗病苦瓜品系的叶片栅栏组织以及海绵组织排列整齐、紧密,而高感品系的叶片组织出现大量孔隙,较难观察到完整细胞。(4)抗病品系叶片厚度、下表皮厚度、栅栏组织厚度、叶片结构紧密度明显高于感病品系,而感病品系的海绵组织厚度、叶片结构疏松度明显高于抗病品系;且苦瓜比叶重与其白粉病抗性关系不大。研究认为,苦瓜叶片蜡质含量、叶背面气孔及茸毛密度可以作为苦瓜白粉病抗性鉴定的参考指标。 相似文献
165.
Young-Jung Lee Dong-Young Choi Yeo-Pyo Yun Sang Bae Han Ki-Wan Oh Jin Tae Hong 《The Journal of nutritional biochemistry》2013,24(1):298-310
Neuroinflammation has been known to play a critical role in the pathogenesis of Alzheimer's disease (AD) through amyloidogenesis. In a previous study, we found that systemic inflammation by intraperitoneal (ip) injection of lipopolysaccharide (LPS) induces neuroinflammation and triggers memory impairment. In this present study, we investigated the inhibitory effects of epigallocatechin-3-gallate (EGCG) on the systemic inflammation-induced neuroinflammation and amyloidogenesis as well as memory impairment. ICR mice were orally administered with EGCG (1.5 and 3 mg/kg) for 3 weeks, and then the mice were treated by ip injection of LPS (250 μg/kg) for 7 days. We found that treatment of LPS induced memory-deficiency-like behavior and that EGCG treatment prevented LPS-induced memory impairment and apoptotic neuronal cell death. EGCG also suppressed LPS-induced increase of the amyloid beta-peptide level and the expression of the amyloid precursor protein (APP), β-site APP cleaving enzyme 1 and its product C99. In addition, we found that EGCG prevented LPS-induced activation of astrocytes and elevation of cytokines including tumor necrosis factor-α, interleukin (IL)-1β, macrophage colony-stimulating factor, soluble intercellular adhesion molecule-1 and IL-16, and the increase of inflammatory proteins, such as inducible nitric oxide synthase and cyclooxygenase-2, which are known factors responsible for not only activation of astrocytes but also amyloidogenesis. In the cultured astrocytes, EGCG also inhibited LPS-induced cytokine release and amyloidogenesis. Thus, this study shows that EGCG prevents memory impairment as well as amyloidogenesis via inhibition of neuroinflammatory-related cytokines released from astrocytes and suggests that EGCG might be a useful intervention for neuroinflammation-associated AD. 相似文献
166.
Tae Young Shin Won Woo Lee Seung Hyun Ko Jae Bang Choi Sung Min Bae Jae Young Choi 《Biocontrol Science and Technology》2013,23(3):288-304
We investigated the occurrence of entomopathogenic fungi in 1080 soil samples representing multiple locations and conditions in Korea. Entomopathogenic fungi were isolated from soils using a selective medium containing dodine and antibiotics. Following an initial identification based on morphology, the fungal isolates were more precisely identified by the sequence of their nuclear ribosomal RNA (rRNA) internal transcribed spacer (ITS) regions. As a result, entomopathogenic fungi were found to occur in 32% (342 isolates) of the soil samples studied. The most abundant species were Beauveria spp. (125 isolates) and Metarhizium spp. (82 isolates). Entomopathogenic fungi were more often recovered from natural mountain and riparian soils than from agricultural habitats. The pathogenicity of isolated fungi was evaluated by using wax moth Galleria mellonella L. (Lepidoptera: Pyralidae) larvae. It was determined that 60% (207 isolates) of the isolates were pathogenic using this model. These entomopathogenic fungi may, therefore, have potential use against a variety of agricultural pests. This is the first study of the isolation and distribution of entomopathogenic fungi in representative sampling locations throughout Korea. 相似文献
167.
Aminoacyl-tRNA synthetase-interacting multifunctional protein-3 (AIMP3) stabilizes and protects mammalian methionyl-tRNA synthetase (MRS) and eukaryotic initiation factor 2 subunit gamma (eIF2γ), factors involved in the formation and the delivery of Met-tRNA i Met respectively, through the binding interactions. Due to the protections that MRS and eIF2γ are provided from the interactions with AIMP3, cellular levels of MRS and eIF2γ may be able to be maintained high enough for their canonical and/or non-canonical functions. 相似文献
168.
Pei-Ling Wang Sang Kyun Koh Kun-Sub Chung Takeshi Uozumi Teruhiko Beppu 《Bioscience, biotechnology, and biochemistry》2013,77(5):1469-1477
We cloned in E. coli the whole 17 nif genes (nifQ-J) of Klebsiella oxytoca NG13 using pBR322 as a vector, and constructed a recombinant plasmid, pNOW25 (nif+, Apr, 42.6 kb). A non nif DNA fragment was deleted from the plasmid with XhoI, and a smaller plasmid, pNOK31 (nif+, Apr, 31.1 kb), was reconstructed.We constructed the restriction map of the cloned nif genes. The map was the same as that of the K. pneumoniae M5a1 nif genes as to the EcoRI, HindIII, BamHI and XhoI sites, but differed considerably in the PstI, SalI and BglII sites.E. coli KO60 containing pNOW25 or pNOK31 can grow on a N-free medium. The acetylene reduction activities of KO60 (pNOW25) and KO60 (pNOK31) were 280 nmol and 390 nmol/48 hr per 7 ml of N-free liquid medium, whereas the activity of K. oxytoca NG13 was 3800 nmol. Thus, the expressed activity of the nif system of K. oxytoca is rather low in E. coli even if the nif genes are cloned on a multicopy plasmid. 相似文献
169.
Seongho Jang Eu Ddeum Park Hyung Joo Suh Sang Hun Lee Jin Soo Kim 《Bioscience, biotechnology, and biochemistry》2013,77(10):1716-1722
To investigate the activity of fermented deer antler on exercise endurance capacity, we evaluated endurance capacity in five-week-old male BALB/c mice by administering the fermented deer antler extract (FA) or the non-fermented deer antler extract (NFA) and then subjected the mice to exercise in the form of swimming. The mice administered 500?mg/kg/day of FA showed a significant increase in swimming time compared with mice administered placebo (16.55?min vs. 21.64?min, P?<?0.05). Serum lactate dehydrogenase (LDH), the marker of the liver and muscle damage, was significantly lower in FA groups. However, NFA groups did not show significantly different swimming time or serum LDH from that of the control group. Moreover, the FA-500 group had significantly higher hepatic superoxide dismutase (SOD) activity after forced swimming than the control and NFA groups (P?<?0.05). These findings suggest that fermentation may increase the exercise endurance capacity of the deer antler. 相似文献
170.
Jae-Myun Ryu Gwi Yeong Jang Dongsun Park Koan Sik Woo Tae Myoung Kim Heon Sang Jeong 《Bioscience, biotechnology, and biochemistry》2013,77(12):2101-2108
ABSTRACTBenign prostatic hyperplasia (BPH) is commonly observed in men > 50 years worldwide. Phytotherapy is one of the many treatment options. Sorghum (Sorghum bicolor L.) contains various health-improving phytochemicals with antioxidant and inhibitory activities on cell proliferation, both in vitro and in vivo. To confirm the effects of Donganme sorghum ethyl-acetate extract (DSEE) on BPH, we induced BPH in Spragye–Dawley rats using exogenous testosterone. We measured prostate weight, examined prostrates histopathologically, and analyzed mRNAs associated with male hormones and proteins associated with cell proliferation in the prostate. DSEE inhibited weight gain of the prostate; decreased mRNA expressions of androgen receptor and 5α-reductase II; and improved histopathological symptoms, the protein-expressed ratio of Bax/Bcl-2, and the oxidative status of BPH induced by testosterone in SD rats. Therefore, DSEE may have potential as a preventive or therapeutic agent against BPH. 相似文献