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11.
Diagnosis and phylogenetic analysis of orf virus in Aleppo and Saanen goats from an outbreak in Turkey 总被引:1,自引:0,他引:1
正Dear Editor,The Poxviridae family is divided into Chordopoxvirinae and Entomopoxvirinae genera.Parapoxvirus is one of 11genera in the Chordopoxvirinae genus,including orf virus(ORFV),bovine papular stomatitis virus(BPSV),pseudocowpox virus(PCPV)and parapoxvirus of red deer in New Zealand(PVNZ)(Skinner et al.,2012).This virus,also known as contagious ecthyma or contagious pustular dermatitis,is a viral skin disease causing edematous proliferative lesions,most often in hairless skin 相似文献
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Enantioseparation of Mandelic Acid Enantiomers With Magnetic Nano‐Sorbent Modified by a Chiral Selector 下载免费PDF全文
In this study, R(+)‐α‐methylbenzylamine‐modified magnetic chiral sorbent was synthesized and assessed as a new enantioselective solid phase sorbent for separation of mandelic acid enantiomers from aqueous solutions. The chemical structures and magnetic properties of the new sorbent were characterized by vibrating sample magnetometry, transmission electron microscopy, Fourier transform infrared spectroscopy, and dynamic light scattering. The effects of different variables such as the initial concentration of racemic mandelic acid, dosage of sorbent, and contact time upon sorption characteristics of mandelic acid enantiomers on magnetic chiral sorbent were investigated. The sorption of mandelic acid enantiomers followed a pseudo‐second‐order reaction and equilibrium experiments were well fitted to a Langmuir isotherm model. The maximum adsorption capacity of racemic mandelic acid on to the magnetic chiral sorbent was found to be 405 mg g?1. The magnetic chiral sorbent has a greater affinity for (S)‐(+)‐mandelic acid compared to (R)‐(?)‐mandelic acid. The optimum resolution was achieved with 10 mL 30 mM of racemic mandelic acid and 110 mg of magnetic chiral sorbent. The best percent enantiomeric excess values (up to 64%) were obtained by use of a chiralpak AD‐H column. Chirality 27:835–842, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
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Kwintkiewicz J Spaczynski RZ Foyouzi N Pehlivan T Duleba AJ 《Biology of reproduction》2006,74(6):1034-1040
Insulin and moderate oxidative stress stimulate proliferation of ovarian theca-interstitial cells. The effects of these agents on selected signal transduction pathways were examined. PD98059 (inhibitor of MAP2K1, also known as MEK-1, upstream of extracellular signal-regulated protein kinases MAPK3/1, also known as ERK1/2), wortmannin (inhibitor of PIK3C2A, also known as PI3K), and rapamycin (inhibitor of FRAP1, also known as mTOR, upstream of RPS6KB1) each significantly decreased insulin and oxidative stress-induced proliferation of theca-interstitial cells. The greatest inhibition was observed in the presence of rapamycin; this effect occurred without a significant change in cell viability. Phosphorylation of AKT was stimulated by insulin only, while phosphorylation of MAPK3/1 and RPS6KB1 was increased by insulin and oxidative stress. Insulin-induced and oxidative stress-induced phosphorylation of RPS6KB1 was partly inhibited by wortmannin and partly by PD98059; the greatest inhibition was observed in the presence of a combination of wortmannin plus PD98059. Effects of insulin and oxidative stress on phosphorylation of RPS6KB1 were confirmed by kinase activity assays. These findings indicate that actions of insulin and oxidative stress converge on MAPK3/1 and RPS6KB1. Furthermore, we speculate that activation of RPS6KB1 may be in part induced via the MAPK3/1 pathway. 相似文献
15.
Bulbul Ahmed Bin Cao Jeffrey S. McLean Tuba Ica Alice Dohnalkova Ozlem Istanbullu Akin Paksoy Jim K. Fredrickson Haluk Beyenal 《Applied and environmental microbiology》2012,78(22):8001-8009
A facultative iron-reducing [Fe(III)-reducing] Paenibacillus sp. strain was isolated from Hanford 300A subsurface sediment biofilms that was capable of reducing soluble Fe(III) complexes [Fe(III)-nitrilotriacetic acid and Fe(III)-citrate] but unable to reduce poorly crystalline ferrihydrite (Fh). However, Paenibacillus sp. 300A was capable of reducing Fh in the presence of low concentrations (2 μM) of either of the electron transfer mediators (ETMs) flavin mononucleotide (FMN) or anthraquinone-2,6-disulfonate (AQDS). Maximum initial Fh reduction rates were observed at catalytic concentrations (<10 μM) of either FMN or AQDS. Higher FMN concentrations inhibited Fh reduction, while increased AQDS concentrations did not. We also found that Paenibacillus sp. 300A could reduce Fh in the presence of natural ETMs from Hanford 300A subsurface sediments. In the absence of ETMs, Paenibacillus sp. 300A was capable of immobilizing U(VI) through both reduction and adsorption. The relative contributions of adsorption and microbial reduction to U(VI) removal from the aqueous phase were ∼7:3 in PIPES [piperazine-N,N′-bis(2-ethanesulfonic acid)] and ∼1:4 in bicarbonate buffer. Our study demonstrated that Paenibacillus sp. 300A catalyzes Fe(III) reduction and U(VI) immobilization and that these reactions benefit from externally added or naturally existing ETMs in 300A subsurface sediments. 相似文献
16.
Antioxidant and radical scavenging properties of curcumin 总被引:3,自引:0,他引:3
Curcumin (diferuoyl methane) is a phenolic compound and a major component of Curcuma longa L. In the present paper, we determined the antioxidant activity of curcumin by employing various in vitro antioxidant assays such as 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH*) scavenging, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, N,N-dimethyl-p-phenylenediamine dihydrochloride (DMPD) radical scavenging activity, total antioxidant activity determination by ferric thiocyanate, total reducing ability determination by the Fe(3+)-Fe(2+) transformation method, superoxide anion radical scavenging by the riboflavin/methionine/illuminate system, hydrogen peroxide scavenging and ferrous ions (Fe(2+)) chelating activities. Curcumin inhibited 97.3% lipid peroxidation of linoleic acid emulsion at 15 microg/mL concentration (20 mM). On the other hand, butylated hydroxyanisole (BHA, 123 mM), butylated hydroxytoluene (BHT, 102 mM), alpha-tocopherol (51 mM) and trolox (90 mM) as standard antioxidants indicated inhibition of 95.4, 99.7, 84.6 and 95.6% on peroxidation of linoleic acid emulsion at 45 microg/mL concentration, respectively. In addition, curcumin had an effective DPPH* scavenging, ABTS*(+) scavenging, DMPD*(+) scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe(3+)) reducing power and ferrous ions (Fe(2+)) chelating activities. Also, BHA, BHT, alpha-tocopherol and trolox, were used as the reference antioxidant and radical scavenger compounds. According to the present study, curcumin can be used in the pharmacological and food industry because of these properties. 相似文献
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Cicek C Karatas T Altuglu I Koturoglu G Kurugol Z Bilgic A 《The new microbiologica》2007,30(2):113-118
The aim of the study was to compare an enzyme immunoassay method with shell vial cell culture method for detection of rotavirus in fecal specimens. In addition, the correlation between laboratory results and clinical scores of patients with gastroenteritis was evaluated. A total of 219 fecal specimens from children (ages 3 weeks to 5 years) with acute gastroenteritis submitted to pediatric emergency room were evaluated by both ELISA and shell vial cell culture. A Vesikari score was used for assessing the severity of the illness. Among 219 stool samples tested, 107 (48.9%) were determined to be positive. Two specimens were positive by shell vial cell culture method while they were ELISA negative. According to these results the calculated sensitivity, specificity, PPV, and NPV of ELISA were 98.1%, 100%, 100%, and 98.2%, respectively. The mean severity score for the 107 episodes of rotavirus diarrhoea was 11.0 +/- 3.6 compared to 4.5 +/- 1.9 for the 112 episodes of non-rotavirus diarrhea in the same population. Our study indicates that ELISA, which is easier to perform, faster and cheaper than cell culture methods may be suitable for routine diagnosis of rotavirus infections. The severity of rotavirus positive gastroenteritis was significantly higher than that of rotavirus negative patients. 相似文献
19.
Bisphenol A (BPA) is an endocrine disruptor chemical, which is commonly used in everyday products. Adverse effects of its exposure are reported even at picomolar doses. Effects of picomolar and nanomolar concentrations of BPA on cytotoxicity, nitric oxide (NO) levels, acetylcholinesterase (AChE) gene expression and activity, and tumor necrosis factor‐α (TNF‐α) and caspase‐8 levels were determined in SH‐SY5Y cells. The current study reveals that low‐dose BPA treatment induced cytotoxicity, NO, and caspase‐8 levels in SH‐SY5Y cells. We also evaluated the mechanism underlying BPA‐induced cell death. Ours is the first report that receptor‐interacting serine/threonine‐protein kinase 1–mediated necroptosis is induced by nanomolar BPA treatment in SH‐SY5Y cells. This effect is mediated by altered AChE and decreased TNF‐α levels, which result in an apoptosis‐necroptosis switch. Moreover, our study reveals that BPA is an activator of AChE. 相似文献
20.
Mojca Jež Tuba Bas Matija Veber Andrej Košir Tanja Dominko Raymond Page Primož Rožman 《Histochemistry and cell biology》2013,139(1):195-204
Immunocytochemistry is a powerful tool for detection and visualization of specific molecules in living or fixed cells, their localization and their relative abundance. One of the most commonly used fluorescent DNA dyes in immunocytochemistry applications is 4′,6-diamidino-2-phenylindole dihydrochloride, known as DAPI. DAPI binds strongly to DNA and is used extensively for visualizing cell nuclei. It is excited by UV light and emits characteristic blue fluorescence. Here, we report a phenomenon based on an apparent photoconversion of DAPI that results in detection of a DAPI signal using a standard filter set for detection of green emission due to blue excitation. When a sample stained with DAPI only was first imaged with the green filter set (FITC/GFP), only a weak cytoplasmic autofluorescence was observed. Next, we imaged the sample with a DAPI filter set, obtaining a strong nuclear DAPI signal as expected. Upon reimaging the same samples with a FITC/GFP filter set, robust nuclear fluorescence was observed. We conclude that excitation with UV results in a photoconversion of DAPI that leads to detection of DAPI due to excitation and emission in the FITC/GFP channel. This phenomenon can affect data interpretation and lead to false-positive results when used together with fluorochrome-labeled nuclear proteins detected with blue excitation and green emission. In order to avoid misinterpretations, extra precaution should be taken to prepare staining solutions with low DAPI concentration and DAPI (UV excitation) images should be acquired after all other higher wavelength images. Of various DNA dyes tested, Hoechst 33342 exhibited the lowest photoconversion while that for DAPI and Hoechst 33258 was much stronger. Different fixation methods did not substantially affect the strength of photoconversion. We also suggest avoiding the use of mounting medium with high glycerol concentrations since glycerol showed the strongest impact on photoconversion. This photoconversion effect cannot be avoided even when using narrow bandpass filter sets. 相似文献