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991.
Ho-Yong Park Soon Sik Park Sang Woon Shin Doo-Sang Park Mi Gwang Kim Hyun Woo Oh Chang Kyeong Joo 《Archives of insect biochemistry and physiology》1997,35(3):335-345
A protein with lytic activity against Micrococcus luteus was purified from the hemolymph of the fall webworm, Hyphantria cunea, larvae challenged with live E. coli. A bacteriolytic protein of about 14,000 daltons in mass was purified by cation exchange chromatography and reverse-phased HPLC. The optimum pH and optimum temperature range for activity were around pH 6.2 and 50°C, respectively, in a 100 mM phosphate buffer. The aminoterminal amino acid sequence of this protein was determined and the corresponding cDNA was isolated and analyzed. The deduced protein of 142 amino acid residues was composed of a putative leader sequence of 20 residues and the mature enzyme of 122 residues. The cloned lysozyme gene was strongly induced in response to bacterial injection, implying that the enzyme is a part of the immune response of H. cunea. Comparison with other known lysozyme sequences shows that our lysozyme belongs to the chicken lysozyme. Arch. Insect Biochem. Physiol. 35:335–345, 1997.© 1997 Wiley-Liss, Inc. 相似文献
992.
Tingting Yi Huifang Chen Jian Zhan Yu Li Zonghong Long Zhuoxi Wu Mi Yang Taotao Peng Hong Li 《Experimental biology and medicine (Maywood, N.J.)》2022,247(2):165
Ubiquinol-cytochrome c reductase core protein 1 (UQCRC1) is an indispensable component of mitochondrial complex III. It plays a key role in cardioprotection and maintaining mitochondrion function. However, the exact role of UQCRC1 in maintaining cardiac function has not been reported by in vivo models. Also, the exact biological functions of UQCRC1 are far from fully understood. UQCRC1+/− mice had decreased both mRNA and protein expression of UQCRC1 in the left ventricular myocardia, and these mice had reduced tolerance to acute exhaustive exercise including decreased time and distance with higher apoptosis rate, higher expression level of cleaved CASPASE 3, and higher ratio of cleaved PARP1 to full-length PARP1. Moreover, UQCRC1 knockdown led to increased LV interventricular septal thicknesses both at systole and diastole, as well as decreased LV volume both at end-systole and end-diastole. Finally, UQCRC1 gene disruption resulted in mitochondrial vacuolation, fibril disarrangement, and more severe morphological and structural changes in mitochondria after acute exhaustive exercise. In conclusion, UQCRC1 contributes to cardiac tolerance to acute exhaustive exercise in mice, and it may be an essential component of complex III, playing a crucial role in maintaining cardiac functions. 相似文献
993.
Qian Zhao ZeYuan Mi Chan Lu XinFei Zhang LiJun Chen ShiQiang Wang JunFeng Niu ZheZhi Wang 《Ecology and evolution》2022,12(2)
Ziziphus spinosa (Bunge) H.H. Hu ex F.H. Chen is a woody plant species of the family Rhamnaceae (order Rhamnales) that possesses high nutritional and medicinal value. Predicting the effects of climate change on the distribution of Z. spinosa is of great significance for the investigation, protection, and exploitation of this germplasm resource. For this study, optimized maximum entropy models were employed to predict the distribution patterns and changes of its present (1970–2000) and future (2050s, 2070s, and 2090s) potential suitable regions in China under multiple climate scenarios (SSP1‐2.6, SSP2‐4.5, SSP3‐7.0 & SSP5‐8.5). The results revealed that the total area of the present potential suitable region for Z. spinosa is 162.60 × 104 km2, which accounts for 16.94% of China''s territory. Within this area, the regions having low, medium, and high suitability were 80.14 × 104 km2, 81.50 × 104 km2, and 0.96 × 104 km2, respectively, with the high suitability regions being distributed primarily in Shanxi, Hebei, and Beijing Provinces. Except for SSP‐1‐2.6‐2070s, SSP‐5‐8.5‐2070s, and SSP‐5‐8.5‐2090s, the suitable areas for Z. spinosa in the future increased to different degrees. Meanwhile, considering the distribution of Z. spinosa during different periods and under different climate scenarios, our study predicted that the low impact areas of Z. spinosa were mainly restricted to Shanxi, Shaanxi, Ningxia, Gansu, Liaoning, Inner Mongolia, and Jilin Provinces. The results of core distributional shifts showed that, except for SSP1‐2.6, the center of the potential suitable region of Z. spinosa exhibited a trend of gradually shifting to the northwest. 相似文献
994.
Fang Xu Wanqing Du Qin Zou Yuting Wang Xin Zhang Xudong Xing Ying Li Dachuan Zhang Huimin Wang Wenhao Zhang Xinyao Hu Xin Liu Xiaoling Liu Shaojin Zhang Jinqiang Yu Jianhuo Fang Fajin Li Ying Zhou Tieqiang Yue Na Mi Haiteng Deng Peng Zou Xiaowei Chen Xuerui Yang Li Yu 《Cell research》2021,31(2):141-156
Cells mitigate ER stress through the unfolded protein response (UPR). Here, we report formation of ER whorls as an effector mechanism of the ER stress response. We found that strong ER stress induces formation of ER whorls, which contain ER-resident proteins such as the Sec61 complex and PKR-like ER kinase (PERK). ER whorl formation is dependent on PERK kinase activity and is mediated by COPII machinery, which facilitates ER membrane budding to form tubular-vesicular ER whorl precursors. ER whorl precursors then go through Sec22b-mediated fusion to form ER whorls. We further show that ER whorls contribute to ER stress-induced translational inhibition by possibly modulating PERK activity and by sequestering translocons in a ribosome-free environment. We propose that formation of ER whorls reflects a new type of ER stress response that controls inhibition of protein translation.Subject terms: Endoplasmic reticulum, Collective cell migration 相似文献
995.
Dilaram Acharya Ji-Hyuk Park Jeong-Hoon Chun Mi Yeon Kim Seok-Ju Yoo Antoine Lewin Kwan Lee 《PLoS neglected tropical diseases》2022,16(2)
The incidence of Q fever has rapidly increased in South Korea since 2015. This study was undertaken to investigate the seroprevalence and seroreactivity of Q fever and the risk factors associated with its seroprevalence among workers in the veterinary service laboratory (VSL) in South Korea. This seroepidemiologic study was conducted in a total of 661 human subjects out of 1,328 subjects working in 50 VSL existing in South Korea between July 15 and July 29, 2019. Data were collected by administering survey questionnaires and by analyzing collected blood samples to determine the presence of antibodies against Coxiella burnetii. The seroprevalence and seroreactivity of C. burnetii infection were determined based on serum titers as (phase II IgG ≥1:256 and/or IgM ≥1:16) and (phase II IgG ≥1:16 and/or IgM ≥1:16) as determined by indirect immunofluorescent assay. Work, work environment, behavioral risk and protective factors associated with seroprevalence of Q fever were assessed by employing multivariable logistic regression analysis. Among the 661, the seroprevalence and seroreactivity of C. burnetii infection were 7.9% and 16.0%, respectively. Multivariate logistic regression analysis showed the risk factors significantly associated with seroprevalence were the antemortem inspection of cattle, goats, or sheep (APR (adjusted prevalence ratio), 2.52; 95% CI, 1.23–4.70)), animal blood splashed into or around eyes (APR, 2.24; 95% CI, 1.04–4.41), and contact with animals having Q fever (APR, 6.58; 95% CI, 3.39–10.85) during the previous year. This study suggests the need for precautions when contact with cattle, goats, or sheep is expected, especially during the antemortem inspection, when dealing with C. burnetii infected animals, or when there is a risk of ocular contact with animal derivatives. Therefore, we recommend the consistent use of appropriate personal protective equipment and other protective measures including PPE treatment and washing of body surfaces after work to prevent C. burnetii infections among VSL staff in South Korea. 相似文献
996.
Ji Heun Jeong Shin Hye Kim Mi Na Park Jong Yea Park Hyun Young Park Chan Eui Song Ji Hyun Moon Ah La Choi Ki Duck Kim Nam Seob Lee Young Gil Jeong Do Kyung Kim Bong Ho Lee Yung Choon Yoo Seung Yun Han 《Current issues in molecular biology》2021,43(1):365
Although the individual consumption of medicinal mushrooms, including Phellinus linteus (PL), Ganoderma lucidum (GL), and Inonotus obliquus (IO), is known to be neuroprotective, the associated mechanisms underlying their therapeutic synergism on focal cerebral ischemia (fCI) have yet to be elucidated. This study aimed to demonstrate the neuroprotective effects of mixed mushroom mycelia (MMM) against experimental fCI. The water-fractions, ethanolic-fractions, and ethyl acetate-fractions of the MMM (PL, GL, and IO) grown in a barley medium using solid-state fermentation techniques were prepared and their protective effects against glutamate-induced excitotoxicity were compared in PC-12 cells. After the identification of the water extracts of MMM (wMMM) as the most suitable form, which possessed the lowest toxicity and highest efficacy, further analyses for evaluating the anti-apoptotic effects of wMMM, including Hoechst 33258-based nuclear staining, fluorescence-activated cell sorting, and reactive oxygen species (ROS) detection assays, were performed. Rats were subjected to a 90 min middle cerebral artery occlusion and reperfusion, after which a wMMM treatment resulted in significant dose-dependent improvements across a number of parameters. Furthermore, measurements of intracellular ROS and levels of antioxidant enzymes revealed a wMMM-mediated ROS attenuation and antioxidant enzyme upregulation. We suggest that wMMM is neuroprotective against fCI through its anti-apoptotic and anti-oxidative effects. 相似文献
997.
998.
Direct adenoviral gene transfer of viral IL-10 to rabbit knees with experimental arthritis ameliorates disease in both injected and contralateral control knees. 总被引:10,自引:0,他引:10
E R Lechman D Jaffurs S C Ghivizzani A Gambotto I Kovesdi Z Mi C H Evans P D Robbins 《Journal of immunology (Baltimore, Md. : 1950)》1999,163(4):2202-2208
IL-10, a cytokine produced primarily by macrophages, B lymphocytes, and Th2 cells, has both immunostimulatory and immunosuppressive properties. A homologue of IL-10 encoded by EBV, known as viral IL-10 (vIL-10), is also able to suppress the immune response, but may lack some of the immunostimulatory properties of IL-10. To evaluate the potential of vIL-10 to block the progression of rheumatoid arthritis, we have utilized a replication-defective adenovirus vector to deliver the gene encoding vIL-10 to the knee joints of rabbits with Ag-induced arthritis. Intraarticular expression of vIL-10 significantly reduced leukocytosis, cartilage matrix degradation, and levels of endogenous rabbit TNF-alpha, as well as the degree of synovitis, while maintaining high levels of cartilage matrix synthesis. Interestingly, an antiarthritic effect was also observed in opposing contralateral control knee joints that received only a marker gene. An adenoviral vector carrying the enhanced green fluorescent protein marker gene was used to demonstrate that a morphologically similar subset of cells infected in the injected knee joint are able to traffic to the uninjected contralateral knee joint. Our results suggest that direct, local intraarticular delivery of the vIL-10 gene may have polyarticular therapeutic effects. 相似文献
999.
Zbigniew Kaniuga Violetta Sączyńska Ewa Miśkiewicz Maciej Garstka 《Acta Physiologiae Plantarum》1999,21(1):45-56
Degradation of leaf polar lipids [monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG), sulfoquinovosyldiacylglycerol
(SQDG) and phosphatidylglycerol (PG)] and chlorophyll (Chl) were studied in four Zea mays genotypes differing in chilling susceptibility following dark chilling and post-chilling rewarming at original growth conditions.
Assessment of visual chilling injury symptoms during post-chilling rewarming differentiated maize inbred lines into chiling-sensitive
(CS) CM7 and Co151 lines and chillingtolerant (CT) S215 and EP1 lines. Severity of chilling injury in CS and CT inbreeds were
correlated with the extent of Chl and polar lipids degradation.
Chilling for either 4 or 6 days followed by 4 days of rewarming caused more extensive degradation of total polar lipids content
in CS than in CT lines. MGDG decreased mostly during chilling whereas DGDG dropped during rewarming only. Chl content was
not affected during chilling but its large decrease, greater in CS than in CT lines, was observed upon rewarming. Extent of
polar lipids breakdown in CS and CT inbreeds during chilling and post-chilling rewarming is correlated with galactolipase
activity in chloroplasts (Kaniuga et al., 1998) and visual assessment of chilling injury.
In view of the data it is likely that contribution of galactolipase activity induced during low-temperature stress of CS plants
is an important factor responsible for thylakoid lipid degradation and development of chilling injury as postulated previously
(Kaniuga 1997). It is suggested that genetically engineered reduction of galactolipase activity or elimination of the factors(s)
involved in induction/stimulation of its activity during chilling might increase tolerance of CS species to chilling stress. 相似文献
1000.
Bacterial CAT gene .with the 35S promoter of CaMV was transferred into leaf discs of cultivar Lycopersicon esculentum 462 with the help of Ti plasmid of Agrobacterium turnefaciens. These leaf discs were placed on MS salt and B5 vitamine medium containing kanamycin and carbenicillin. Several kinds of phytohormones were chosen in the medium, and it was found that zeatin and NAA have great effects on shooting and rooting. Transgenic tomato plants showed their normal flowering and fruiting. Leaves of these transgenic tomato plants were used for assaying the gene expression. Resuits of Southern Blot showed that the CAT gene was stably integrated into the genome of transgenic plants, The bacterial CAT, proteins were also detected, in transgenic tomato leaves with immunoreaction of CAT antibody. The methods presented here for culturing transformed tomato ceils will be a great help for transfering economically important genes into cultivars of tomato plants in China. 相似文献