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N. A. Terragno A. J. Lonigro K. U. Malik J. C. McGiff 《Cellular and molecular life sciences : CMLS》1972,28(4):437-439
Zusammenfassung Nachweis, dass Bradykinin den renalen Blutstrom um 58% der Kontrollwerte (282±40 ml min) erhöht und gleichzeitig im venösen Nierenblut die Konzentration einer Substanz, welche die physicochemischen und biologischen Eigenschatten eines Prostaglandins der E-Serie besitzt, steigert, wobei die Konzentration einer PGF-ähnlichen Substanz unverändert blieb. 相似文献
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A blend of small molecules regulates both mating and development in Caenorhabditis elegans 总被引:1,自引:0,他引:1
Srinivasan J Kaplan F Ajredini R Zachariah C Alborn HT Teal PE Malik RU Edison AS Sternberg PW Schroeder FC 《Nature》2008,454(7208):1115-1118
In many organisms, population-density sensing and sexual attraction rely on small-molecule-based signalling systems. In the nematode Caenorhabditis elegans, population density is monitored through specific glycosides of the dideoxysugar ascarylose (the 'ascarosides') that promote entry into an alternative larval stage, the non-feeding and highly persistent dauer stage. In addition, adult C. elegans males are attracted to hermaphrodites by a previously unidentified small-molecule signal. Here we show, by means of combinatorial activity-guided fractionation of the C. elegans metabolome, that the mating signal consists of a synergistic blend of three dauer-inducing ascarosides, which we call ascr#2, ascr#3 and ascr#4. This blend of ascarosides acts as a potent male attractant at very low concentrations, whereas at the higher concentrations required for dauer formation the compounds no longer attract males and instead deter hermaphrodites. The ascarosides ascr#2 and ascr#3 carry different, but overlapping, information, as ascr#3 is more potent as a male attractant than ascr#2, whereas ascr#2 is slightly more potent than ascr#3 in promoting dauer formation. We demonstrate that ascr#2, ascr#3 and ascr#4 are strongly synergistic, and that two types of neuron, the amphid single-ciliated sensory neuron type K (ASK) and the male-specific cephalic companion neuron (CEM), are required for male attraction by ascr#3. On the basis of these results, male attraction and dauer formation in C. elegans appear as alternative behavioural responses to a common set of signalling molecules. The ascaroside signalling system thus connects reproductive and developmental pathways and represents a unique example of structure- and concentration-dependent differential activity of signalling molecules. 相似文献
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Cell-specific and lamin-dependent targeting of novel transmembrane proteins in the nuclear envelope 总被引:1,自引:1,他引:0
Poonam Malik Nadia Korfali Vlastimil Srsen Vassiliki Lazou Dzmitry G. Batrakou Nikolaj Zuleger Deirdre M. Kavanagh Gavin S. Wilkie Martin W. Goldberg Eric C. Schirmer 《Cellular and molecular life sciences : CMLS》2010,67(8):1353-1369
Nuclear envelope complexity is expanding with respect to identification of protein components. Here we test the validity of
proteomics results that identified 67 novel predicted nuclear envelope transmembrane proteins (NETs) from liver by directly
comparing 30 as tagged fusions using targeting assays. This confirmed 21 as NETs, but 4 only targeted in certain cell types,
underscoring the complexity of interactions that tether NETs to the nuclear envelope. Four NETs accumulated at the nuclear
rim in normal fibroblasts but not in fibroblasts lacking lamin A, suggesting involvement of lamin A in tethering them in the
nucleus. However, intriguingly, for the NETs tested alternative mechanisms for nuclear envelope retention could be found in
Jurkat cells that normally lack lamin A. This study expands by a factor of three the number of liver NETs analyzed, bringing
the total confirmed to 31, and shows that several have multiple mechanisms for nuclear envelope retention. 相似文献
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Smith UM Consugar M Tee LJ McKee BM Maina EN Whelan S Morgan NV Goranson E Gissen P Lilliquist S Aligianis IA Ward CJ Pasha S Punyashthiti R Malik Sharif S Batman PA Bennett CP Woods CG McKeown C Bucourt M Miller CA Cox P Algazali L Trembath RC Torres VE Attie-Bitach T Kelly DA Maher ER Gattone VH Harris PC Johnson CA 《Nature genetics》2006,38(2):191-196
Meckel-Gruber syndrome is a severe autosomal, recessively inherited disorder characterized by bilateral renal cystic dysplasia, developmental defects of the central nervous system (most commonly occipital encephalocele), hepatic ductal dysplasia and cysts and polydactyly. MKS is genetically heterogeneous, with three loci mapped: MKS1, 17q21-24 (ref. 4); MKS2, 11q13 (ref. 5) and MKS3 (ref. 6). We have refined MKS3 mapping to a 12.67-Mb interval (8q21.13-q22.1) that is syntenic to the Wpk locus in rat, which is a model with polycystic kidney disease, agenesis of the corpus callosum and hydrocephalus. Positional cloning of the Wpk gene suggested a MKS3 candidate gene, TMEM67, for which we identified pathogenic mutations for five MKS3-linked consanguineous families. MKS3 is a previously uncharacterized, evolutionarily conserved gene that is expressed at moderate levels in fetal brain, liver and kidney but has widespread, low levels of expression. It encodes a 995-amino acid seven-transmembrane receptor protein of unknown function that we have called meckelin. 相似文献
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Sohail Iqbal Malik 《Systemic Practice and Action Research》2018,31(6):637-656
Programming is a rewarding and yet demanding field in the ICT labormarket, but it is considered a challenging and difficult area of learning for significant numbers of novice programmers. As a result, high attrition rates from introductory programming (IP) courses are reported despite extensive research which attempts to address the issue. In this research, an action research methodology was used with three cycles to investigate and improve the teaching and learning process of the IP course. There were nine activities performed during the span of these three cycles. All three entities of the didactic triangle (student, instructor, and content) together with learning context were incorporated into the research design to understand the problem better and execute the proposed solution. The result shows that three cycles of the action research methodology helps in understanding and improving the students learning outcomes in the IP course. Moreover, the attrition rate was also reduced in the IP course. 相似文献
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Vijaykrishna D Smith GJ Pybus OG Zhu H Bhatt S Poon LL Riley S Bahl J Ma SK Cheung CL Perera RA Chen H Shortridge KF Webby RJ Webster RG Guan Y Peiris JS 《Nature》2011,473(7348):519-522
Swine influenza A viruses (SwIV) cause significant economic losses in animal husbandry as well as instances of human disease and occasionally give rise to human pandemics, including that caused by the H1N1/2009 virus. The lack of systematic and longitudinal influenza surveillance in pigs has hampered attempts to reconstruct the origins of this pandemic. Most existing swine data were derived from opportunistic samples collected from diseased pigs in disparate geographical regions, not from prospective studies in defined locations, hence the evolutionary and transmission dynamics of SwIV are poorly understood. Here we quantify the epidemiological, genetic and antigenic dynamics of SwIV in Hong Kong using a data set of more than 650 SwIV isolates and more than 800 swine sera from 12?years of systematic surveillance in this region, supplemented with data stretching back 34?years. Intercontinental virus movement has led to reassortment and lineage replacement, creating an antigenically and genetically diverse virus population whose dynamics are quantitatively different from those previously observed for human influenza viruses. Our findings indicate that increased antigenic drift is associated with reassortment events and offer insights into the emergence of influenza viruses with epidemic potential in swine and humans. 相似文献