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121.
Hannah L. Smith Alix K. Berglund James B. Robertson Lauren V. Schnabel Richard J. McMullen Jr Brian C. Gilger Annie Oh 《Veterinary ophthalmology》2023,26(4):347-354
Objective
The objective of the study was to determine the effect of gentamicin on CD3+ T-lymphocyte proliferation and cell viability using an in vitro cell culture model as a means of investigating the mechanism of action of low-dose intravitreal gentamicin injection.Animals Studied
Three adult horses with no evidence of ophthalmic or systemic disease.Procedure
Peripheral blood lymphocytes were treated with gentamicin at concentrations 37.5 μg/mL, 112.5 μg/mL, 187 μg/mL, 375 μg/mL, or 750 μg/mL then stimulated to proliferate with concanavalin A (ConA). 4′,6-diamidino-2-phenylindole (DAPI) and carboxyfluoroscein succinimidyl ester (CSFE) were used as markers of cell viability and cell proliferation, respectively. Following 5-day culture, live cell counts and CSFE fluorescent intensity data were collected via automated cell count and flow cytometry. The experimental design was duplicated using preservative-free gentamicin and a proprietary brand formulation. Statistical analysis was performed using two-way ANOVA with Tukey's multiple comparison test.Results
No statistically significant comparisons in CD3+ T-lymphocyte live cell counts and geometric mean fluorescent intensity of CSFE were identified between gentamicin concentrations or formulations.Conclusions
Gentamicin had no effect on equine peripheral blood CD3+ T-lymphocyte cell viability and proliferation in concentrations ranging from “safe” to “retinotoxic” in relation to intravitreal injection volumes. Low-dose intravitreal gentamicin may not suppress the Th1- and Th17-mediated immune response. 相似文献122.
Influenza A is a respiratory disease common in the swine industry. Three subtypes, H1N1, H1N2 and H3N2 influenza A viruses, are currently co-circulating in swine populations in Korea. An outbreak of the highly pathogenic avian influenza H5N1 virus occurred in domestic bird farms in Korea during the winter season of 2003. Pigs can serve as hosts for avian influenza viruses, enabling passage of the virus to other mammals and recombination of mammalian and avian influenza viruses, which are more readily transmissible to humans. This study reports the current seroprevalence of swine H1 and H3 influenza in swine populations in Korea by hemagglutination inhibition (HI) assay. We also investigated whether avian H5 and H9 influenza transmission occurred in pigs from Korea using both the HI and neutralization (NT) tests. 51.2% (380/742) of serum samples tested were positive against the swine H1 virus and 43.7% (324/742) were positive against the swine H3 virus by HI assay. The incidence of seropositivity against both the swine H1 virus and the swine H3 virus was 25.3% (188/742). On the other hand, none of the samples tested showed seropositivity against either the avian H5 virus or the avian H9 virus by the HI and NT tests. Therefore, we report the high current seroprevalence and co-infectivity of swine H1 and H3 influenza viruses in swine populations and the lack of seroepidemiological evidence of avian H5 and H9 influenza transmission to Korean pigs. 相似文献
123.
124.
Kim J Kim JH Choi KH Kim JH Song YS Cha J 《Journal of agricultural and food chemistry》2011,59(16):8675-8682
AprE51 from Bacillus amyloliquefaciens CH51 is a 27 kDa subtilisin-like protease with fibrinolytic activity. To enhance the catalytic activity of AprE51, two residues, Gly-169 and Ser-101, which, according to the three-dimensional structural model of subtilisin, are located in the P1 substrate-binding site and S3 subsite, respectively, were mutated by site-directed mutagenesis. Results of the mutational analysis showed that substitution of alanine for Gly-169 increased the fibrinolytic activity 1.4-fold. All four Ser-101 mutations, that is, replacements with arginine, leucine, lysine, and tryptophan, also increased the fibrinolytic activity up to 3.9-fold. The S101W mutant with a bulky side chain was more active than mutants with a positively charged or nonpolar small side chains. The fibrinolytic activity of the S101W mutant was further increased by error-prone polymerase chain reaction. The AprE51-6 mutant (S101W/G169A/V192A) had stronger fibrinolytic activity than the S101W mutant. Purified AprE51-6 had a 2.5-fold higher k(cat) and a 2.3-fold lower K(m), which resulted in a 6-fold increase in catalytic efficiency (k(cat)/K(m)) relative to that of wild-type AprE51. In addition, AprE51-6 showed a relatively broader pH range and increased thermostability as compared to AprE51. 相似文献
125.
Kimchi-Sarfaty C Oh JM Kim IW Sauna ZE Calcagno AM Ambudkar SV Gottesman MM 《Science (New York, N.Y.)》2007,315(5811):525-528
Synonymous single-nucleotide polymorphisms (SNPs) do not produce altered coding sequences, and therefore they are not expected to change the function of the protein in which they occur. We report that a synonymous SNP in the Multidrug Resistance 1 (MDR1) gene, part of a haplotype previously linked to altered function of the MDR1 gene product P-glycoprotein (P-gp), nonetheless results in P-gp with altered drug and inhibitor interactions. Similar mRNA and protein levels, but altered conformations, were found for wild-type and polymorphic P-gp. We hypothesize that the presence of a rare codon, marked by the synonymous polymorphism, affects the timing of cotranslational folding and insertion of P-gp into the membrane, thereby altering the structure of substrate and inhibitor interaction sites. 相似文献
126.
K. Panneerselvam Chigen Tsukamoto Nozomi Honda Akio Kikuchi Jeong‐Dong Lee Seung‐Hwan Yang Gyuhwa Chung 《Plant Breeding》2013,132(1):121-126
Seed saponin composition of 3025 wild soybean (Glycine soja Sieb. and Zucc.) accessions collected from nine regions of Korea was analysed by thin‐layer chromatography to determine its polymorphic variation and geographical distribution and find mutants in saponin components. The saponin composition of seed hypocotyls was primarily divided into seven phenotypes, designated as Aa, Ab, AaBc, AbBc, Aa+α, AaBc+α and AbBc+α. The predominant phenotypes were AaBc (55%), Aa (33%), AaBc+α (7.5%) and Aa+α (3.3%). The frequencies of Ab, AbBc and AbBc+α were very low (0.3‐0.5%). Codominant alleles Sg‐1a and Sg‐1b and dominant allele Sg‐4 occupied 98.6, 1.1 and 63.3%, respectively. Alleles Sg‐3 and Sg‐5 were found to be dominant in all the analysed accessions except the mutants. Three accessions were discovered as mutants via LC‐PDA/MS/MS. The accession CWS0115 did not produce saponin Aa and Ax, CWS2133 did not produce saponin Aa and Ab and CWS5095 did not produce any group A saponins. These newly determined mutants might be utilized in producing a new soybean variety with good taste as well as in biosynthetic studies. 相似文献
127.
Extra‐Firm Networks and Firm Performance: A Study of South Korean Solar PV Firms and Industry Specific Government Actors 下载免费PDF全文
Extra‐firm actors have been acknowledged as vital to the success of green energy industries. This article deploys the firm network perspective to deliver a first of its kind analysis of specific extra‐firm actor impacts on firm performance in Korea's solar photovoltaic industry. Results are based on quantitative analyses of data from 60 firm respondents and augmented by interviews with eight government officials. Three research questions capture and compare firm and government actor perceptions pertaining to extra‐firm actor influences at the national, regional, and extra‐local scales, inclusive of place–place competition and cooperation. Results indicate that firms differ in perceptions related to the impact of 18 national level government institutes, R&D centers, associations, and academic societies on their success, and that perceptions vary by level of technology concerning a plethora of other related extra‐firm actor and support infrastructure impacts. A comparative perspective is presented based on government informant interviews. 相似文献
128.
Rauf Muhammad Yoon Hyemyeong Lee Sukyeung Shin Myoung-Jae Ko Ho-Cheol Lee Myung-Chul Oh Sejong Hyun Do-Yoon Hur Onsook Choi Yu Mi 《Journal of Crop Science and Biotechnology》2019,22(5):495-507
Journal of Crop Science and Biotechnology - Oat (Avena sativa L.) is one of the world’s most important cereal crops, owing to its use as an important source of essential nutrients for both... 相似文献
129.
Feng DL Lu DH Shen KM Kim C Eisaki H Damascelli A Yoshizaki R Shimoyama J Kishio K Gu GD Oh S Andrus A O'Donnell J Eckstein JN Shen Z 《Science (New York, N.Y.)》2000,289(5477):277-281
We report that the doping and temperature dependence of photoemission spectra near the Brillouin zone boundary of Bi(2)Sr(2)CaCu(2)O(8+delta)exhibit unexpected sensitivity to the superfluid density. In the superconducting state, the photoemission peak intensity as a function of doping scales with the superfluid density and the condensation energy. As a function of temperature, the peak intensity shows an abrupt behavior near the superconducting phase transition temperature where phase coherence sets in, rather than near the temperature where the gap opens. This anomalous manifestation of collective effects in single-particle spectroscopy raises important questions concerning the mechanism of high-temperature superconductivity. 相似文献
130.
Understanding the nature of solid-liquid interfaces is important for many processes of technological interest, such as solidification, liquid-phase epitaxial growth, wetting, liquid-phase joining, crystal growth, and lubrication. Recent studies have reported on indirect evidence of density fluctuations at solid-liquid interfaces on the basis of x-ray scattering methods that have been complemented by atomistic simulations. We provide evidence for ordering of liquid atoms adjacent to an interface with a crystal, based on real-time high-temperature observations of alumina-aluminum solid-liquid interfaces at the atomic-length scale. In addition, crystal growth of alumina into liquid aluminum, facilitated by interfacial transport of oxygen from the microscope column, was observed in situ with the use of high-resolution transmission electron microscopy. 相似文献