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81.
Asif J. Iqbal Daniel Regan-Komito Ivy Christou Gemma E. White Eileen McNeill Amy Kenyon Lewis Taylor Theodore S. Kapellos Edward A. Fisher Keith M. Channon David R. Greaves 《PloS one》2013,8(3)
Chemotaxis assays are an invaluable tool for studying the biological activity of inflammatory mediators such as CC chemokines, which have been implicated in a wide range of chronic inflammatory diseases. Conventional chemotaxis systems such as the modified Boyden chamber are limited in terms of the data captured given that the assays are analysed at a single time-point. We report the optimisation and validation of a label-free, real-time cell migration assay based on electrical cell impedance to measure chemotaxis of different primary murine macrophage populations in response to a range of CC chemokines and other chemoattractant signalling molecules. We clearly demonstrate key differences in the migratory behavior of different murine macrophage populations and show that this dynamic system measures true macrophage chemotaxis rather than chemokinesis or fugetaxis. We highlight an absolute requirement for Gαi signaling and actin cytoskeletal rearrangement as demonstrated by Pertussis toxin and cytochalasin D inhibition. We also studied the chemotaxis of CD14+ human monocytes and demonstrate distinct chemotactic profiles amongst different monocyte donors to CCL2. This real-time chemotaxis assay will allow a detailed analysis of factors that regulate macrophage responses to chemoattractant cytokines and inflammatory mediators. 相似文献
82.
Uhlén M Björling E Agaton C Szigyarto CA Amini B Andersen E Andersson AC Angelidou P Asplund A Asplund C Berglund L Bergström K Brumer H Cerjan D Ekström M Elobeid A Eriksson C Fagerberg L Falk R Fall J Forsberg M Björklund MG Gumbel K Halimi A Hallin I Hamsten C Hansson M Hedhammar M Hercules G Kampf C Larsson K Lindskog M Lodewyckx W Lund J Lundeberg J Magnusson K Malm E Nilsson P Odling J Oksvold P Olsson I Oster E Ottosson J Paavilainen L Persson A Rimini R Rockberg J Runeson M Sivertsson A 《Molecular & cellular proteomics : MCP》2005,4(12):1920-1932
Antibody-based proteomics provides a powerful approach for the functional study of the human proteome involving the systematic generation of protein-specific affinity reagents. We used this strategy to construct a comprehensive, antibody-based protein atlas for expression and localization profiles in 48 normal human tissues and 20 different cancers. Here we report a new publicly available database containing, in the first version, approximately 400,000 high resolution images corresponding to more than 700 antibodies toward human proteins. Each image has been annotated by a certified pathologist to provide a knowledge base for functional studies and to allow queries about protein profiles in normal and disease tissues. Our results suggest it should be possible to extend this analysis to the majority of all human proteins thus providing a valuable tool for medical and biological research. 相似文献
83.
The superior performance of F1 hybrids has a significant impact on agricultural productivity. For commercial application, the availability of an efficient
system for obtaining male-sterile lines of crops is an essential prerequisite. Here we have investigated the use of RNA interference
(RNAi) technology to silence a male-specific gene in the model host tobacco. TA29 is expressed exclusively in anthers at the time of microspore development. About 10 out of 13 tobacco lines transformed with
a hairpin RNAi construct containing TA29 sequences were male sterile. Transgenic plants were phenotypically indistinguishable from non-transgenic plants. At the anthesis
stage, pollen grains from transgenic, male-sterile plants were aborted and lysed in comparison to the round and fully developed
pollen in non-transgenic plants. Microscopic analysis of anthers showed selective degradation of tapetum in transgenic plants
with no microspore development. One week after self-pollination, the ovules of non-transgenic plants were double the size
of those in transgenic plants, due to successful self-fertilization. Male sterile transgenic plants set seed normally, when
cross-pollinated with pollen from non-transgenic plants, confirming no adverse effect on the female parts of the flower. These
results show that silencing of male-specific genes by RNAi is potentially a useful tool for generating male-sterile lines
for producing hybrid seed. 相似文献
84.
A.U. Mahmud A.K.M.A. Hoque Md. Rejwan Bhuiyan M.E. Kabir Asif Mahmud 《Archives Of Phytopathology And Plant Protection》2013,46(19):2295-2304
A field experiment was conducted to investigate the effect of some management practices to minimise jute yellow mosaic virus disease. The management practices were employed at natural condition and placed randomly with four replications. The treatments were spraying malathion 57 EC, rouging and field sanitation, top dressing of nitrogenous fertiliser, mulching with straw and untreated control. The highest percentage of mosaic incidence was recorded in control and the lowest incidence was recorded in top dressing of nitrogenous fertiliser. Among the treatments, top dressing of nitrogenous fertiliser showed the best performance in terms of increasing yield (3.05?t/ha). The second highest was obtained in rouging and field sanitation which was statistically similar to spraying malathion 57 EC. The best gross margin ($379.02/ha) and increase of gross margin (63.00%) compared to control were achieved in top dressing of nitrogenous fertiliser with the highest benefit-cost ratio (4.84). However, the treatments were found significantly profitable compared to the control indicating the usefulness of the cultural practices in integrated disease management programme for healthy and profitable jute cultivation. 相似文献
85.
Ali Zohaib Muhammad Saqib Muhammad Ammar Athar Jing Chen Awais-ur-Rahman Sial Saeed Khan Zeeshan Taj Halima Sadia Usman Tahir Muhammad Haleem Tayyab Muhammad Asif Qureshi Muhammad Khalid Mansoor Muhammad Ahsan Naeem Bing-Jie Hu Bilal Ahmed Khan Ikram Din Ujjan Bei Li Wei Zhang Yun Luo Yan Zhu Cecilia Waruhiu Iahtasham Khan Xing-Lou Yang Muhammad Sohail Sajid Victor Max Corman Bing Yan Zheng-Li Shi 《中国病毒学》2018,33(5):410-417
Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is a zoonotic pathogen capable of causing severe respiratory disease in humans. Although dromedary camels are considered as a major reservoir host, the MERS-CoV infection dynamics in camels are not fully understood. Through surveillance in Pakistan, nasal (n = 776) and serum (n = 1050)samples were collected from camels between November 2015 and February 2018. Samples were collected from animal markets, free-roaming herds and abattoirs. An in-house ELISA was developed to detect IgG against MERS-CoV. A total of 794 camels were found seropositive for MERS-CoV. Prevalence increased with the age and the highest seroprevalence was recorded in camels aged [ 10 years (81.37%) followed by those aged 3.1–10 years (78.65%) and B 3 years (58.19%).Higher prevalence was observed in female (78.13%) as compared to male (70.70%). Of the camel nasal swabs, 22 were found to be positive by RT-qPCR though with high Ct values. Moreover, 2,409 human serum samples were also collected from four provinces of Pakistan during 2016–2017. Among the sampled population, 840 humans were camel herders.Although we found a high rate of MERS-CoV antibody positive dromedaries (75.62%) in Pakistan, no neutralizing antibodies were detected in humans with and without contact to camels. 相似文献
86.
Onion (Allium cepa L.) is protandrous in nature and requires cross‐pollination to avoid inbreeding. The pollination potential of native bees (Hymenoptera) and true flies (Diptera) was assessed in the perspective of finding the best pollinators for onion cross‐pollination and seed multiplication. The community of pollinators was composed of four bee species and twelve true fly species. Episyrphus balteatus, Eupeodes sp., Musca domestica and Eristalinus aeneus were the most abundant pollinators. The maximum pollinator activity was observed from 12 to 24 days after opening of the flowers. The pollination effectiveness of tested bees (Apis dorsata and Apis florea) was greater than true flies (E. balteatus, Eupeodes sp., M. domestica, E. aeneus and Callihoridae sp.) in terms of Spears values. 相似文献
87.
A pig kidney cDNA library was screened for the porcine ortholog of the multispecific organic anion transporter 1 (pOAT1). Several positive clones were isolated resulting in two alternatively spliced cDNA clones of pOAT1 (pOAT1 and pOAT1A). pOAT1-cDNAs consist of 2126 or 1895 base pairs (EMBL Acc. No. AJ308234 and AJ308235) encoding 547 or 533 amino acid residue proteins with 89, 87, 83 and 81% homology to the human, rabbit, rat, and mouse OAT1, respectively. Heterologous expression of pOAT1 in Xenopus laevis oocytes revealed an apparent K(m) for [3H]PAH of 3.75 +/- 1.6 microM. [3H]PAH uptake mediated by pOAT1 was abolished by 0.5 mM glutarate or 1 mM probenecid. Functional characterization of pOAT1A did not show any affinity for [3H]PAH. In summary, we cloned two alternative splice variants of the pig ortholog of organic anion transporter 1. One splice form (pOAT1) showed typical functional characteristics of organic anion transporter 1, whereas the second form appears not to transport PAH. 相似文献
88.
Cai J Wu L Qi X Shaw L Li Calzi S Caballero S Jiang WG Vinores SA Antonetti D Ahmed A Grant MB Boulton ME 《PloS one》2011,6(3):e18076
Increased vascular permeability is an early event characteristic of tissue ischemia and angiogenesis. Although VEGF family members are potent promoters of endothelial permeability the role of placental growth factor (PlGF) is hotly debated. Here we investigated PlGF isoforms 1 and 2 and present in vitro and in vivo evidence that PlGF-1, but not PlGF-2, can inhibit VEGF-induced permeability but only during a critical window post-VEGF exposure. PlGF-1 promotes VE-cadherin expression via the trans-activating Sp1 and Sp3 interaction with the VE-cadherin promoter and subsequently stabilizes transendothelial junctions, but only after activation of endothelial cells by VEGF. PlGF-1 regulates vascular permeability associated with the rapid localization of VE-cadherin to the plasma membrane and dephosphorylation of tyrosine residues that precedes changes observed in claudin 5 tyrosine phosphorylation and membrane localization. The critical window during which PlGF-1 exerts its effect on VEGF-induced permeability highlights the importance of the translational significance of this work in that PLGF-1 likely serves as an endogenous anti-permeability factor whose effectiveness is limited to a precise time point following vascular injury. Clinical approaches that would pattern nature's approach would thus limit treatments to precise intervals following injury and bring attention to use of agents only during therapeutic windows. 相似文献
89.
Asif Qasim Kerry Malpass Daniel J O'Gorman Mary E Heber 《BMJ (Clinical research ed.)》2002,324(7349):1328-1331
ProblemDelay in starting thrombolytic treatment in patients arriving at hospital with chest pain who are diagnosed as having acute myocardial infarction.DesignAudit of “door to needle times” for patients presenting with chest pain and an electrocardiogram on admission that confirmed acute myocardial infarction. A one year period in each of three phases of development was studied.
Background and setting
The goal of the national service framework for coronary heart disease is that by April 2002, 75% of eligible patients should receive thrombolysis within 30 minutes of arriving at hospital. A district general hospital introduced a strategy to improve door to needle times. In phase 1 (1989-95), patients with suspected acute myocardial infarction, referred by general practitioners, were assessed in the coronary care unit; all other patients were seen first in the accident and emergency department. In phase 2 (1995-7), all patients with suspected acute myocardial infarction were transferred directly to a fast track area within the coronary care unit, where nurses assess patients and doctors started treatment.Key measures for improvement
Median door to needle time in phase 1 of 45 minutes (range 5-300 minutes), with 38% of patients treated within 30 minutes. Median door to needle time in phase 2 of 40 minutes (range 5-180 minutes), with 47% treated within 30 minutesStrategies for change
In phase 3 (1997-2001), all patients with suspected acute myocardial infarction were transferred directly to the fast track area and assessed by a “coronary care thrombolysis nurse.” If electrocardiography confirmed the diagnosis of acute myocardial infarction, the nurse could initiate thrombolytic therapy (subject to guidelines and exclusions determined by the consultant cardiologists).Effects of change
Median door to needle time in phase 3 of 15 minutes (range 5-70 minutes), with 80% of patients treated within 30 minutes. Systematic clinical review showed no cases in which a nurse initiated inappropriate thrombolysis.Lessons learnt
Thrombolysis started by nurses is safe and effective in patients with acute myocardial infarction. It may provide a way by which the national service framework''s targets for door to needle times can be achieved. 相似文献90.
Asif?S.?Tamboli Pradnya?B.?Yadav Aatiya?A.?Gothe Shrirang?R.?Yadav Sanjay?P.?GovindwarEmail author 《Plant Systematics and Evolution》2018,304(2):205-217
Capparis (Capparaceae) has been used as a medicinal plant since ancient time. Capparis species were divided into Old World and New World taxa as described by the sectional division of Capparis. However, plastid DNA sequence data of Indian Capparis species were not analyzed in previous phylogenetic studies. Here, we have added Indian Capparis data in previous phylogeny and analyzed the relationship of Indian Capparis with Old World and New World taxa. The plastid phylogeny presented here includes Capparis taxa from its major distribution areas, New World and African capparoids. The presented phylogeny is used for the determination of biogeographic history of Capparis and recently segregated genera. Phylogenetic analyses of the combined plastid data revealed that the Indian Capparis are more closely related to Old World taxa and have connections with African, Australian and Eastern Asian species. Sectional classification of Old World and Indian Capparis considered in this study is reflected from the presented plastid phylogeny. The ancestral area reconstruction using Bayesian Binary Markov Chain Monte Carlo method strongly supports for the Africa as the ancestral region for both Old World and New World Capparis. Molecular marker-based genetic diversity studies on Indian Capparis are scarce. This work also includes the genetic diversity study of Indian Capparis species. Utility and efficacy of ISSR markers to study inter- and intraspecies variation in Capparis is evident from the AMOVA results. 相似文献