Condensed-matter physics. Reprise of first experiment casts doubt on supersolid helium     

Cho A 《Science (New York, N.Y.)》2012,336(6082):661

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Astronomy. How hot is dark matter?     

Cho A 《Science (New York, N.Y.)》2012,336(6085):1091-1092

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Antiviral activity of Alpinia katsumadai extracts against rotaviruses     

Kim HH  Kwon HJ  Ryu YB  Chang JS  Cho KO  Hosmillo MD  Rho MC  Park SJ  Lee WS 《Research in veterinary science》2012,92(2):320-323

In vitro anti-rotavirus activity of Alpinia katsumadai (AK) extracts were evaluated against bovine G8P[7] and porcine G5P[7] rotaviruses in two different assay strategies, a mixed treatment assay and a post treatment assay. In the mixed treatment assay, six AK extracts [AK-1 (EtOH extract), AK-3 (H(2)O layer), AK-5 (40% methanol fraction), and AK-9-11 (H(2)O extract, polysaccharide fraction, supernatant fraction)] exhibited inhibitory activities against G5P[7] rotavirus with the EC(50) values ranging from 0.7±0.4 to 33.7±6.5 μg/mL. Extracts AK-1, AK-3, and AK-5 inhibited rotavirus infection against G8P[7] rotavirus, the with EC(50) values of 8.4±2.2 μg/mL, 6.5±0.8 μg/mL and 8.4±5.0 μg/mL, respectively. By hemagglutination inhibition (HI) assay, six AK extracts completely inhibited viral adsorption onto human RBCs in both strains of rotaviruses at less than 11 μg/mL. However, in the post treatment assay, there was no anti activity shown against both strains of rotaviruses. As a result, six AK extracts were attributed mainly to having a strong interaction with hemagglutinin protein on the outer surface of rotavirus, resulting to blockage of viral adsorption.  相似文献   

Cyproconazole impregnation into wood using sub- and supercritical carbon dioxide     

Sung-Mo Kang  Myeung-Won Cho  Kwon-Min Kim  Dong-yeop Kang  Won-Mo Koo  Kyu-Hyeok Kim  Jong-Young Park  Sung-Suk Lee 《Wood Science and Technology》2012,46(4):643-656

Supercritical fluid (SCF) impregnation is a promising preservative treatment method for wood. In order to commercialize the sub- and supercritical CO₂ biocide treatment, better understanding of the fluid phase and its effect on treatment results have to be demonstrated and developed. Preservative treatability under super- and subcritical fluid conditions was evaluated using radiata pine sapwood, and treating characteristics in relation to different fluid phases and treatability were discussed. Various treatment conditions resulted in varying biocide retentions and distributions. Higher pressure conditions enhanced biocide retentions resulting from increasing biocide input in the applied saturation method. Subcritical CO₂ condition produced higher biocide retentions and little retention gradients from face to core. Subcritical CO₂ treatment has a couple of benefits such as investment costs and energy consumption compared with supercritical CO₂.  相似文献   

Animal Biowarfare Research: Historical Perspective and Potential Future Attacks     

Jung‐Yong Yeh  Jee‐Yong Park  Yun Sang Cho  In‐Soo Cho 《Zoonoses and public health》2012,59(8):536-544

A biological attack on livestock or poultry could result in the loss of valuable animals, costs related to the containment of outbreaks and the disposal of carcasses, lost trade and other economic effects involving suppliers, transporters, distributors and restaurants; however, it is not possible to secure all livestock, and livestock are much less well guarded than human targets. Thus, the vulnerability of the livestock industry to the introduction of biological agents varies for the following reasons: (i) the majority of lethal and contagious biological agents are environmentally resilient, endemic in foreign countries and harmless to humans, making it easier for terrorists to acquire, handle and deploy these pathogens, (ii) with animals concentrated in fewer production facilities and frequently transported between these facilities, a single pathogen introduction could cause widespread infection and (iii) the extent of human travel around the globe makes it difficult to exclude exotic animal diseases as possible biological agents. Historically, many governments have developed and planned to use biological agents for direct attacks on livestock or poultry. In the past, developed nations have actively developed biological weapons to target animals. The potential spectrum of bioterrorism ranges from isolated acts against individuals by individuals to tactical and strategic military attacks and state‐sponsored international terrorism intended to cause mass casualties in animals, humans or both. This review provides an overview of the past development and use of biological weapons and describes potential future attacks.  相似文献   

Detection and molecular characterization of porcine type 3 orthoreoviruses circulating in South Korea     

Kwon HJ  Kim HH  Kim HJ  Park JG  Son KY  Jung J  Lee WS  Cho KO  Park SJ  Kang MI 《Veterinary microbiology》2012,157(3-4):456-463

Orthoreoviruses infect virtually all mammalian species, causing systemic infections including mild gastrointestinal and respiratory illnesses. However, little is known about the prevalence or genetic diversity of porcine orthoreoviruses in South Korea. We examined 237 diarrheic fecal samples collected from 78 pig farms around the country. RT-PCR utilizing primers specific for the L1 gene of mammalian orthoreoviruses showed that 45 (19.0%) samples were positive. The 10 strains isolated from orthoreovirus-positive samples formed typical perinuclear cytoplasmic inclusion bodies and had an atypical hemagglutination pattern; these are characteristics of type 3 orthoreovirus. Phylogenetic analysis of the S1 gene in these 10 Korean and other strains showed that type 3 orthoreoviruses could be divided into four lineages; the 10 Korean strains were included in porcine lineage IV, along with T3/porcine/Sichuan/2006. Sequence analysis showed that strains in lineage IV had nucleotide identities of 97.0-98.1% and deduced amino acid identities of 96.4-98.2%. Sequence analysis of the σ1 protein, a viral attachment protein, revealed that the amino acid sequences associated with neurotropism (amino acids 198-204, 249I, 350D, and 419E) were highly conserved among the Korean strains, confirming that neural tropism was present. In conclusion, our findings suggest that porcine orthoreovirus infections are endemic in pig farms in South Korea and that the 10 novel Korean porcine orthoreoviruses belong to porcine lineage IV of type 3 orthoreovirus. In addition, sequence analysis of S1 genes encoding the σ1 protein showed that the 9 of 10 Korean porcine orthoreoviruses exhibited neural tropism.  相似文献   

Pathogenicity characterization of a bovine triple reassortant rotavirus in calves and piglets   总被引：1，自引：0，他引：1  

Kim HJ  Park JG  Alfajaro MM  Kim DS  Hosmillo M  Son KY  Lee JH  Bae YC  Park SI  Kang MI  Cho KO 《Veterinary microbiology》2012,159(1-2):11-22

Rotaviruses are important human and animal pathogens with high impact on public health and livestock industry. There is little evidence about the cross-species pathogenicity and extra-intestinal infections of animal and human reassortant rotaviruses, particularly based on all 11 genotyping data. In this study, the bovine triple reassortant KJ56-1 strain harboring two bovine-like genome segments, eight porcine-like genome segments, and one human-like genome segment was used to evaluate the cross-species pathogenicity in its parent species, calves and piglets, and to determine its abilities of causing viremia and extra-intestinal tropisms in piglets. The KJ56-1 strain isolated from a calf diarrhea fecal sample replicated without causing diarrhea and severe intestinal pathology in calves. However, piglets inoculated with this strain showed persistent severe diarrhea and marked intestinal pathology. By SYBR Green real-time RT-PCR, viral RNA was detected in the sera, mesenteric lymph node, lung, liver, choroid plexus, and cerebrospinal fluid in the experimental piglets. An immunofluorescence assay confirmed viral replication in these extra-intestinal organs and tissues. These results indicated that the bovine triple reassortant KJ56-1 strain was virulent to piglets but not to calves. Our data also demonstrated that the reassortant rotaviruses had the ability to spread to the bloodstream from the gut, enter and amplify in the mesenteric lymph node, and disseminate to the extra-intestinal organs and tissues.  相似文献   

Dietary sophorolipid accelerates growth by modulation of gut microbiota population and intestinal environments in broiler chickens     

Min-Jin Kwak  Min-Young Park  Yong-Soon Choi  Junghwan Cho  Duleepa Pathiraja  Jonggun Kim  Hanbae Lee  In-Geol Choi  Kwang-Youn Whang 《畜牧与生物技术杂志(英文版)》2022,(1):256-264

Background:Gut is a crucial organ for the host’s defense system due to its filtering action of the intestinal membrane from hazardous foreign substances.One strategy to strengthen the gut epithelial barrier function is to upregulate beneficial microflora populations and their metabolites.Sophorolipid(SPL),which is a glycolipid biosurfactant,could increase beneficial microflora and decrease pathogenic bacteria in the gastrointestinal tract.Therefore,herein,we conducted an experiment with broiler chickens to investigate the fortifying effects of SPL on the host’s gut defense system by modulating the microbiota population.Methods:A total of 5401-day-old chicks(Ross 308)were used,and they were immediately allotted into three treatment groups(6 replications with 30 chicks/pen)according to their initial body weight.The dietary treatments consisted of CON(basal diet),BAM(10 mg/kg bambermycin),and SPL(10 mg/kg SPL).During the experiment,birds freely accessed feed and water,and body weight and feed intake were measured at the end of each phase.On d 35,birds(one bird/pen)were sacrificed to collect jejunum and cecum samples.Results:Dietary SPL and BAM supplementation significantly accelerated birds’growth and also significantly improved feed efficiency compared to CON.Intestinal microbial community was significantly separated by dietary SPL supplementation from that of CON,and dietary SPL supplementation significantly increased Lactobacillus spp.and Akkermansia muciniphila.Moreover,birds fed with dietary SPL also showed the highest concentration of cecal butyrate among all treatment groups.Gut morphological analysis showed that dietary SPL significantly increased villus height,ratio of villus height to crypt depth,goblet cell numbers,and the gene expression levels of claudin-1 and mucin 2.Additionally,dietary SPL significantly decreased the mRNA expression level of pro-inflammatory cytokine,interleukin-6,and increased that of anti-inflammatory cytokine,interleukin-10,compared to other treatments.Conclusions:Dietary SPL increases the beneficial bacterial population and butyrate concentration,which leads to a strengthened gut barrier function.In addition,the intestinal inflammation was also downregulated by dietary SPL supplementation.  相似文献   

Distribution and characterization of class 1 integrons in Salmonella enterica serotype Gallinarum biotype Gallinarum     

Kwon HJ  Kim TE  Cho SH  Seol JG  Kim BJ  Hyun JW  Park KY  Kim SJ  Yoo HS 《Veterinary microbiology》2002,89(4):303-309

Fowl typhoid caused by Salmonella enterica subsp. enterica serotype Gallinarum biotype Gallinarum is the most important chicken disease in Korea. Due to appearance of new or multiple antibiotics resistances in the recently isolated strains, it was difficult to control the disease using antibiotics in our country. Therefore, the prevalence and genetic contents of class 1 integrons in biotype Gallinarum isolated between 1992 and 2001 were investigated by PCR and direct sequencing, respectively. Out of 90 strains, 35 (39%) carried class 1 integrons. The 1.0, 1.6 and 2.0kbp amplicons were amplified in 32 strains (36%), 2 strains (2%) and 1 strain (1%), respectively. The 1.0, 1.6 and 2.0 kbp amplicons contained one (aadA1a), two (aadB-aadA1b) and three cassettes (dhfrXII-orfF-aadA2), respectively, providing resistances against aminoglycosides (aadA1a, aadA1b, aadB, and aadA2) and trimethoprim (dhfrXII). The integron-carrying strains of biotype Gallinarum appeared in 1996 and acquired additional cassettes in 2000. Although the resistances to ampicillin, tetracycline and chloramphenicol are unrelated to class 1 integrons, relatively high prevalence of integron in biotype Gallinarum may be a dormant threat to the chemotherapy of the disease in the near future because of potency to acquire additional antibiotics resistances.  相似文献   

Comparative analysis of physicochemicals and antioxidative properties in new red rice (Oryza sativa L. cv. Gunganghongmi)     

Woo Duck Seo  Jun Young Kim  You-Chun Song  Jun-Hyun Cho  Ki Chang Jang  Sang-Ik Han  Ji-Eun Ra  Seong-Hwan Oh  Hyeon-Jung Kang  Byung-Joo Kim  Nam-In Baek  Rak-Hun Jeong  Min Hee Nam 《Journal of Crop Science and Biotechnology》2013,16(1):63-68

The main objectives of this study were to investigate physicochemicals and antioxidant activities of new red rice (Oryza sativa cv. Gunganghongmi (GH)) by comparing normal brown (Nampyeongbyeo, NB) and reported red rice (Jukjinjubyeo, JB) in Korea. The nutritional constituents, including protein, oil, sugar, fatty acid, GABA, and γ-oryzanol were not significantly different between normal brown and colored rice. However, the ethanol extract of GH showed the highest phenolic content (24.7 ± 1.3 mg g^?1). The ethanol extracts of GH showed higher scavenging activities against DPPH (0.2 mg mL^?1 = 62.1 ± 2.5%) and ABTS (0.2 mg mL^?1 = 63.2 ± 3.5%) radicals. Moreover, GH more inhibited LPS-induced nitric oxide (NO) production (13.2 ± 1.4 μM) than JB (18.3 ± 2.3 μM) and NB (22.1 ± 1.4 μM) at the same concentration (0.2 mg mL^?1) without cytotoxicity. These results suggest that new red rice (GH) would be considered to be new functional rice due to its anti-oxidative effect and high nutrition.  相似文献