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Aqeela Ashraf Muhammad Imran Tahir Yaqub Muhammad Tayyab Wasim Shehzad Claro N. Mingala Yung-Fu Chang 《Folia microbiologica》2018,63(3):373-380
Mycoplasma mastitis is often difficult to control due to a lack of rapid and accurate diagnostic tools. The aim of the current study was to develop a loop-mediated isothermal amplification (LAMP) assay for the detection of Mycoplasma bovis (M. bovis) in mastitic milk. The assay was developed using primers designed for three different target genes: uvrC, 16S rRNA, and gyrB, and validated using mastitic milk samples previously found positive for the target pathogen. Specificity of the developed assay was determined by testing cross-reactivity of LAMP primers against closely related bovine mastitis bacterial pathogens. The sensitivity was found to be higher compared to conventional polymerase chain reaction (PCR). The LAMP assay was also capable of detecting M. bovis in PCR-negative milk samples of cows with clinical mastitis. The uvrC primers were found to be more sensitive, while gyrB primers were more specific; however, 16S rRNA primers were less specific and sensitive compared to either uvrC or gyrB primers. Cohen’s kappa values for uvrC, gyrB, and 16S rRNA primers used in the LAMP assays were 0.940, 0.970, and 0.807, respectively. There was a high level of agreement between the test results and the true-disease status as indicated by the receiver operating characteristic (ROC) curve. Our findings suggest that the newly developed LAMP assays targeting the uvrC and gyrB genes could be a useful tool for rapid and accurate diagnosis of mastitis caused by M. bovis. 相似文献
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J. Mocco Aqeela Afzal Saeed Ansari Annemarie Wolfe Kenneth Caldwell E S. Connolly Edward W. Scott 《PloS one》2014,9(1)
Background
Hematopoietic stem cells mobilize to the peripheral circulation in response to stroke. However, the mechanism by which the brain initiates this mobilization is uncharacterized.Methods
Animals underwent a murine intraluminal filament model of focal cerebral ischemia and the SDF1-A pathway was evaluated in a blinded manner via serum and brain SDF1-A level assessment, Lin−/Sca1+ cell mobilization quantification, and exogenous cell migration confirmation; all with or without SDF1-A blockade.Results
Bone marrow demonstrated a significant increase in Lin−/Sca1+ cell counts at 24 hrs (272±60%; P<0.05 vs sham). Mobilization of Lin−/Sca1+ cells to blood was significantly elevated at 24 hrs (607±159%; P<0.05). Serum SDF1-A levels were significant at 24 hrs (Sham (103±14), 4 hrs (94±20%, p = NS) and 24 hrs (130±17; p<0.05)). Brain SDF1-A levels were significantly elevated at both 4 hrs and 24 hrs (113±7 pg/ml and 112±10 pg/ml, respectively; p<0.05 versus sham 76±11 pg/ml). Following administration of an SDF1-A antibody, Lin−/Sca1+ cells failed to mobilize to peripheral blood following stroke, despite continued up regulation in bone marrow (stroke bone marrow cell count: 536±65, blood cell count: 127±24; p<0.05 versus placebo). Exogenously administered Lin−/Sca1+ cells resulted in a significant reduction in infarct volume: 42±5% (stroke alone), versus 21±15% (Stroke+Lin−/Sca1+ cells), and administration of an SDF1-A antibody concomitant to exogenous administration of the Lin−/Sca1+ cells prevented this reduction. Following stroke, exogenously administered Lin−/Sca1+ FISH positive cells were significantly reduced when administered concomitant to an SDF1-A antibody as compared to without SDF1-A antibody (10±4 vs 0.7±1, p<0.05).Conclusions
SDF1-A appears to play a critical role in modulating Lin−/Sca1+ cell migration to ischemic brain. 相似文献3.
Julia Wallmeier Diana Bracht Hessa S. Alsaif Gerard W. Dougherty Heike Olbrich Sandra Cindric Mark Dzietko Christoph Heyer Norbert Teig Charlotte Thiels Eissa Faqeih Aqeela Al-Hashim Sameena Khan Ibrahim Mogarri Mohammed Almannai Wadha Al Otaibi Fowzan S. Alkuraya Cordula Koerner-Rettberg Heymut Omran 《American journal of human genetics》2021,108(7):1318-1329
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Identifying differentially expressed genes is critical in microarray data analysis. Many methods have been developed by combining p-value, fold-change, and various statistical models to determine these genes. When using these methods, it is necessary to set up various pre-determined cutoff values. However, many of these cutoff values are somewhat arbitrary and may not have clear connections to biology. In this study, a genetic distance method based on gene expression level was developed to analyze eight sets of microarray data extracted from the GEO database. Since the genes used in distance calculation have been ranked by fold-change, the genetic distance becomes more stable when adding more genes in the calculation, indicating there is an optimal set of genes which are sufficient to characterize the stable difference between samples. This set of genes is differentially expressed genes representing both the genotypic and phenotypic differences between samples. 相似文献
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Iqbal Ahmad Zubair Anwar Kefi Iqbal Syed Abid Ali Tania Mirza Adeela Khurshid Aqeela Khurshid Adeel Arsalan 《AAPS PharmSciTech》2014,15(3):550-559
The photolysis of riboflavin (RF) in the presence of acetate buffer (pH 3.8–5.6) and carbonate buffer (pH 9.2–10.8) has been studied using a multicomponent spectrophotometric method for the simultaneous assay of RF and its photoproducts. Acetate and carbonate buffers have been found to catalyze the photolysis reaction of RF. The apparent first-order rate constants for the acetate-catalyzed reaction range from 0.20 to 2.86 × 10−4 s−1 and for the carbonate-catalyzed reaction from 3.33 to 15.89 × 10−4 s−1. The second-order rate constants for the interaction of RF with the acetate and the carbonate ions range from 2.04 to 4.33 × 10−4 M−1 s−1 and from 3.71 to 11.80 × 10−4 M−1 s−1, respectively. The k-pH profile for the acetate-catalyzed reaction is bell shaped and for the carbonate-catalyzed reaction a steep curve. Both HCO3− and CO32 − ions are involved in the catalysis of the photolysis reaction in alkaline solution. The rate constants for the HCO3− and CO32 − ions catalyzed reactions are 0.72 and 1.38 × 10−3 M−1 s−1, respectively, indicating a major role of CO32 − ions in the catalysis reaction. The loss of RF fluorescence in acetate buffer suggests an interaction between RF and acetate ions to promote the photolysis reaction. The optimum stability of RF solutions is observed in the pH range 5–6, which is suitable for pharmaceutical preparations.KEY WORDS: acetate effect, carbonate effect, photolysis, riboflavin, spectrophotometric assay 相似文献
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G. Paganga H. Al-Hashim H. Khodr B. C. Scott O. I. Aruoma R. C. Hider 《Redox report : communications in free radical research》2013,18(6):359-364
AbstractThe seleno-organic compound ebselen mimics the glutathione-dependent, hydroperoxide reducing activity of glutathione peroxidase. The activity of glutathione peroxidase determines the rate of hydroperoxide-induced Ca2+ release from mitochondria. Ebselen stimulates Ca2+ release from mitochondria, accelerates mitochondrial respiration and uncoupling, and induces mitochondrial swelling, indicating a deterioration of mitochondrial function. These manifestations are abolished by cyclo-sporine A, a potent inhibitor of the mitochondrial permeability transition. However, when ebselen-induced Ca2+ cycling is prevented with ruthenium red, an inhibitor of the Ca2+ uniporter, or by chelation of extramitochondrial Ca2+ by EGTA, no detectable elevation of swelling or uncoupling is observed. The release of Ca2+ from mitochondria is delayed in the absence of rotenone, i.e. when pyridine nucleotides are maintained in the reduced state due to succinate-driven reversed electron flow. We suggest that ebselen induces Ca2+ release from intact mitochondria via an NAD+ hydrolysis-dependent mechanism. 相似文献
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Saeed Ansari Hassan Azari Douglas J. McConnell Aqeela Afzal J Mocco 《Journal of visualized experiments : JoVE》2011,(51)
Stroke is the third leading cause of death and the leading cause of disability in the world, with an estimated cost of near $70 billion
in the United States in 20091,2. The intraluminal middle cerebral artery occlusion (MCAO) model was developed by Koizumi4 in 1986 to simulate this
impactful human pathology in the rat. A modification of the MCAO method was later presented by Longa3. Both techniques have been widely used to identify
molecular mechanisms of brain injury resulting from ischemic stroke and potential therapeutic modalities5. This relatively noninvasive method in rats has been
extended to use in mice to take advantage of transgenic and knockout strains6,7. To model focal cerebral ischemia, an intraluminal suture is advanced via
the internal carotid artery to occlude the base of the MCA. Retracting the suture after a specified period of time mimics spontaneous reperfusion, but the
suture can also be permanently retained. This video will be demonstrating the two major approaches for performing intraluminal MCAO procedure in mice in a
stepwise fashion, as well as providing insights for potential drawbacks and pitfalls. The ischemic brain tissue will subsequently be stained by
2,3,5-triphenyltetrazolium chloride (TTC) to evaluate the extent of cerebral infarction8. Download video file.(77M, mov) 相似文献
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