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991.
992.
Kwon D Shin K Kim S Ha Y Choi JH Yang JS Lee JY Chae C Oh HB Kang C 《Journal of microbiology (Seoul, Korea)》2010,48(5):657-662
This study aimed to characterize the replication and pathogenic properties of a Korean pandemic (H1N1) 2009 influenza virus
isolate in ferrets and mice. Ferrets infected with A/Korea/01/2009 (H1N1) virus showed mild clinical signs. The virus replicated
well in lungs and slightly in brains with no replication in any other organs. Severe bronchopneumonia and thickening of alveolar
walls were detected in the lungs. Viral antigens were detected in the bronchiolar epithelial cells, in peribronchial glands
with severe peribronchitis and in cells present in the alveoli. A/Korea/01/2009 (H1N1) virus-infected mice showed weight loss
and pathological lung lesions including perivascular cuffing, interstitial pneumonia and alveolitis. The virus replicated
highly in the lungs and slightly in the nasal tissues. Viral antigens were detected in bronchiolar epithelial cells, pneumocytes
and interstitial macrophages. However, seasonal H1N1 influenza virus did not replicate in the lungs of ferrets, and viral
antigens were not detected. Thus, this Korean pandemic (H1N1) 2009 isolate infected the lungs of ferrets and mice successfully
and caused more pathological lesions than did the seasonal influenza virus. 相似文献
993.
Park IS Park JU Seo MJ Kim MJ Lee HH Kim SR Kang BW Choi YH Joo WH Jeong YK 《Journal of microbiology (Seoul, Korea)》2010,48(6):836-841
A fibrinolytic enzyme of the mushroom, Schizophyllum commune was purified with chromatographic methods, including a DEAE-Sephadex A-50 ion-exchange column and gel filtrations with Sephadex
G-75 and Sephadex G-50 columns. The analysis of fibrin-zymography and SDS-PAGE showed that the enzyme was a monomeric subunit
that was estimated to be approximately 17 kDa in size. The fibrinolytic activity of the enzyme in plasminogen-rich and plasminogen-free
fibrin plates was 1.25 and 0.44 U/ml, respectively. The N-terminal amino acid sequence of the purified enzyme was identified
as HYNIXNSWSSFID, which was highly distinguished from known fibrinolytic enzymes. The relative activity of the purified enzyme
with an addition of 5 mM EDTA, Phosphoramidon, and Bestatin was about 76, 64, and 52%, respectively, indicating that it is
a metalloprotease. The optimum temperature for the purified enzyme was approximately 45°C, and over 87% of the enzymatic activity
was maintained as a stable state in a pH range from 4.0 to 6.0. Therefore, our results suggest that the potential thrombolytic
agent from S. commune is a unique type of fibrinolytic enzyme. 相似文献
994.
Selvaraj T Kim SK Kim YH Jeong YS Kim YJ Phuong ND Jung KH Kim J Yun HD Kim H 《Journal of microbiology (Seoul, Korea)》2010,48(6):856-861
A non-cellulosomal xylanase from Clostridium thermocellum, XynX, consists of a family-22 carbohydratebinding module (CBM22), a family-10 glycoside hydrolase (GH10) catalytic module, two family-9 carbohydrate-binding modules (CBM9-I and CBM9-II), and an S-layer homology (SLH) module. E. coli BL21(DE3) (pKM29), a transformant carrying xynX', produced several truncated forms of the enzyme. Among them, three major active species were purified by SDS-PAGE, activity staining, gel-slicing, and diffusion from the gel. The truncated xylanases were different from each other only in their C-terminal regions. In addition to the CBM22 and GH10 catalytic modules, XynX(1) had the CBM9-I and most of the CBM9-II, XynX(2) had the CBM9-I and about 40% of the CBM9-II, and XynX(3) had about 75% of the CBM9-I. The truncated xylanases showed higher binding capacities toward Avicel than those toward insoluble xylan. XynX(1) showed a higher affinity toward Avicel (70.5%) than XynX(2) (46.0%) and XynX(3) (42.1%); however, there were no significant differences in the affinities toward insoluble xylan. It is suggested that the CBM9 repeat, especially CBM9-II, of XynX plays a role in xylan degradation in nature by strengthening cellulose binding rather than by enhancing xylan binding. 相似文献
995.
Microbial communities in hot pepper (Capsicum annuum L.) cultivation fields under different cultivation methods were investigated by terminal restriction fragment length polymorphism
(T-RFLP) analysis. Rhizosphere soil and leaf samples were collected from control, conventional and nature-friendly cultivation
fields between May and July, 2009. Two Bacillus subtilis strains were applied to nature-friendly cultivation fields as biocontrol agents during the sampling period. Relative abundances
of bacteria and plant pathogenic fungi related T-RFs were also measured to monitor the effect of biocontrol agents on potential
plant pathogenic fungi. In the principal component analysis (PCA) based on T-RFLP profiles, the microbial communities from
rhizosphere soil samples in July, including bacteria and fungi, showed distinct difference between nature-friendly cultivation
fields and other cultivation fields. However, there was no correlation between cultivation methods and leaf microbial communities
at any sampling period. Changes in the abundance of bacteria related T-RF in the rhizosphere of nature-friendly cultivation
fields were observed clearly two months after application of biocontrol agent, while the abundance of plant pathogenic fungi
related T-RFs significantly decreased. 相似文献
996.
Eun Hye Kim Kyeung Hee Cho Yung Mi Lee Joung Han Yim Hong Kum Lee Jang-Cheon Cho Soon Gyu Hong 《Journal of microbiology (Seoul, Korea)》2010,48(4):426-432
A new approach for enrichment culture was applied to obtain cold-active protease-producing bacteria for marine and terrestrial samples from Svalbard, Norway. The method was developed for the enrichment of bacteria by long-term incubation at low temperatures in semi-solid agar medium containing meat pieces as the main source of carbon and energy. ZoBell and 0.1× nutrient broth were added for marine and terrestrial microorganisms, respectively, to supply basal elements for growth. One to three types of colonies were observed from each enrichment culture, indicating that specific bacterial species were enriched during the experimental conditions. Among 89 bacterial isolates, protease activity was observed from 48 isolates in the screening media containing skim milk. Good growth was observed at 4°C and 10°C while none of the isolates could grow at 37°C. At low temperatures, enzyme activity was equal to or higher than activity at higher temperatures. Bacterial isolates were included in the genera Pseudoalteromonas (33 isolates), Arthrobacter (24 isolates), Pseudomonas (16 isolates), Psychrobacter (6 isolates), Sphingobacterium (6 isolates), Flavobacterium (2 isolates), Sporosarcina (1 isolate), and Stenotrophomonas (1 isolate). Protease activity was observed from Pseudoalteromonas (33 isolates), Pseudomonas (10 isolates), Arthrobacter (4 isolates), and Flavobacterium (1 isolate). 相似文献
997.
998.
Jae Cheol Kong Myeong Soo Lee Byung-Cheul Shin Yung-Sun Song Edzard Ernst 《CMAJ》2010,182(16):1723-1729
Background
Acupuncture is frequently advocated as an adjunct treatment during stroke rehabilitation. The aim of this review was to assess its effectiveness in this setting.Methods
We searched 25 databases and 12 major Korean traditional medicine journals from their inception to October 2009. We included randomized controlled trials, with no language restrictions, that compared the effects of acupuncture (with or without electrical stimulation) with sham acupuncture. We assessed the methodologic quality of the trials using the Cochrane risk-of-bias criteria and the PEDro (Physiotherapy Evidence Database) scale.Results
Ten of 664 potentially relevant studies met our inclusion criteria. For acute and subacute stages after stroke, we included seven trials. A meta-analysis of the five studies that assessed functionality did not show a significant difference in favour of acupuncture, with high heterogeneity. A post-hoc sensitivity analysis of three trials with low risk of bias did not show beneficial effects of acupuncture on activities of daily living at the end of the intervention period (n = 244; standard mean difference 0.07, 95% confidence interval [CI] −0.18 to 0.32; I2 = 0%) or after follow-up (n = 244; standard mean difference 0.10, 95% CI −0.15 to 0.35; I2 = 0%). For the chronic stage after stroke, three trials tested effects of acupuncture on function according to the Modified Ashworth Scale; all failed to show favourable effects.Interpretation
Our meta-analyses of data from rigorous randomized sham-controlled trials did not show a positive effect of acupuncture as a treatment for functional recovery after stroke.Acupuncture is often used as an adjunct to mainstream rehabilitation after stroke. It involves the insertion of an acupuncture needle into the skin at certain points of the body. Acupuncture is claimed to be effective for a wide range of conditions, such as pain, musculoskeletal disorders and several neurologic diseases.1 Possible mechanisms of its effects on neurologic conditions include stimulation of neuronal cell proliferation,2 facilitation of neural plasticity,3 reduction of the post-ischemic inflammatory reaction4 and prevention of neuronal apoptosis.5Before acupuncture can be recommended for routine use, we require evidence from rigorous randomized clinical trials. In acupuncture trials, it is difficult to allow blinding of the treatment allocation.6 A placebo must be indistinguishable from the real treatment and inert.6 “Sham” is used to describe any control procedure that is used to blind treatment allocation in clinical trials of acupuncture.6 Several sham procedures are now available, such as the use of penetrating acupuncture on nonacupuncture points, superficial puncture of the skin on acupuncture points and nonpenetration on acupuncture points with sham needle devices.6Several reviews assessing the effects of acupuncture for stroke have been published. However, some did not include all of the relevant articles published in Asian countries; others included interventions other than acupuncture; and several were not systematic. We conducted a systematic review to critically evaluate all of the currently available randomized sham-controlled trials of acupuncture as an adjunct to mainstream stroke rehabilitation. 相似文献999.
1000.
Mi Jin Yoon Eun Hee Kim Jun Hee Lim Taeg Kyu Kwon Kyeong Sook Choi 《Free radical biology & medicine》2010,48(5):713-726
Curcumin is considered a pharmacologically safe agent that may be useful in cancer chemoprevention and therapy. Here, we show for the first time that curcumin effectively induces paraptosis in malignant breast cancer cell lines, including MDA-MB-435S, MDA-MB-231, and Hs578T cells, by promoting vacuolation that results from swelling and fusion of mitochondria and/or the endoplasmic reticulum (ER). Inhibition of protein synthesis by cycloheximide blocked curcumin-induced vacuolation and subsequent cell death, indicating that protein synthesis is required for this process. The levels of AIP-1/Alix protein, a known inhibitor protein of paraptosis, were progressively downregulated in curcumin-treated malignant breast cancer cells, and AIP-1/Alix overexpression attenuated curcumin-induced death in these cells. ERK2 and JNK activation were positively associated with curcumin-induced cell death. Mitochondrial superoxide was shown to act as a critical early signal in curcumin-induced paraptosis, whereas proteasomal dysfunction was mainly responsible for the paraptotic changes associated with ER dilation. Notably, curcumin-induced paraptotic events were not observed in normal breast cells, including mammary epithelial cells and MCF-10A cells. Taken together, our findings on curcumin-induced paraptosis may provide novel insights into the mechanisms underlying the selective anti-cancer effects of curcumin against malignant cancer cells. 相似文献