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1.
The effect of phosphinothricin concentration on embryo production from an embryogenic callus of Chancellor (Vitis L. complex interspecific hybrid) was tested. Embryogenic callus was cultured on medium supplemented with nine phosphinothricin concentrations (0, 0.1, 0.5, 1, 1.5, 2, 3, 5, and 10 mg/l). The highest number of embryos per plate was observed at 0.5 mg/l phosphinothricin. The use of phosphinothricin to stimulate embryo production did not affect embryo germination and plantlet formation. Three germination techniques were compared. Embryo dehydration or growth on Transfergelsolidified medium gave higher germination rates than chilling treatments. Most germinated somatic embryos produced secondary embryos from the hypocotyl after a few weeks of culture. Regardless of the germination technique, the plantlet conversion rate was very low.Abbreviations AC
activated charcoal
- 2,4-D
2,4-dichlorophenoxyacetic acid
- BA
6-benzylaminopurine
- MS
Murashige and Skoog (1962) basal medium
- NN
Nitsch and Nitsch (1969) medium
- PPT
phosphinothricin 相似文献
2.
Sarah H. Ross Emma Spanjaard Anneke Post Marjolein J. Vliem Hendy Kristyanto Johannes L. Bos Johan de Rooij 《PloS one》2012,7(11)
We developed new image analysis tools to analyse quantitatively the extracellular-matrix-dependent cell spreading process imaged by live-cell epifluorescence microscopy. Using these tools, we investigated cell spreading induced by activation of the small GTPase, Rap1. After replating and initial adhesion, unstimulated cells exhibited extensive protrusion and retraction as their spread area increased, and displayed an angular shape that was remodelled over time. In contrast, activation of endogenous Rap1, via 007-mediated stimulation of Epac1, induced protrusion along the entire cell periphery, resulting in a rounder spread surface, an accelerated spreading rate and an increased spread area compared to control cells. Whereas basal, anisotropic, spreading was completely dependent on Src activity, Rap1-induced spreading was refractory to Src inhibition. Under Src inhibited conditions, the characteristic Src-induced tyrosine phosphorylations of FAK and paxillin did not occur, but Rap1 could induce the formation of actomyosin-connected adhesions, which contained vinculin at levels comparable to that found in unperturbed focal adhesions. From these results, we conclude that Rap1 can induce cell adhesion and stimulate an accelerated rate of cell spreading through mechanisms that bypass the canonical FAK-Src-Paxillin signalling cascade. 相似文献
3.
4.
Ran Zhang Zhihui Zhao Yaofeng Zhao Imre Kacskovics Marjolein van der Eijk Nanda de Groot 《Animal biotechnology》2013,24(4):242-246
In this study, we evaluated haplotypes of the bovine FCGRT (encoding the FcRn heavy chain) and their relationship to the IgG concentration in bovine colostrum. Four single nucleotide polymorphism (SNP), classified into five haplotypes, were identified in a total of 49 Holstein-Frisians cows. Haplotype 5 was found to be significantly associated with a high IgG level ([OR] = 9.90, 95%CI = 1.11–88.34, p = 0.016) and haplotype 2 exhibited a similar trend ([OR] = 2.89, 95%CI = 1.17–7.11, p = 0.019). 相似文献
5.
Audrey J. King Saskia van der Lee Archena Mohangoo Marjolein van Gent Arno van der Ark Bas van de Waterbeemd 《PloS one》2013,8(6)
Bordetella pertussis (B. pertussis) is the causative agent of whooping cough, which is a highly contagious disease in the human respiratory tract. Despite vaccination since the 1950s, pertussis remains the most prevalent vaccine-preventable disease in developed countries. A recent resurgence pertussis is associated with the expansion of B. pertussis strains with a novel allele for the pertussis toxin (ptx) promoter ptxP3 in place of resident ptxP1 strains. The recent expansion of ptxP3 strains suggests that these strains carry mutations that have increased their fitness. Compared to the ptxP1 strains, ptxP3 strains produce more Ptx, which results in increased virulence and immune suppression. In this study, we investigated the contribution of gene expression changes of various genes on the increased fitness of the ptxP3 strains. Using genome-wide gene expression profiling, we show that several virulence genes had higher expression levels in the ptxP3 strains compared to the ptxP1 strains. We provide the first evidence that wildtype ptxP3 strains are better colonizers in an intranasal mouse infection model. This study shows that the ptxP3 mutation and the genetic background of ptxP3 strains affect fitness by contributing to the ability to colonize in a mouse infection model. These results show that the genetic background of ptxP3 strains with a higher expression of virulence genes contribute to increased fitness. 相似文献
6.
Marjolein P. Brekelmans Niki Fens Paul Brinkman Lieuwe D. Bos Peter J. Sterk Paul P. Tak Dani?lle M. Gerlag 《PloS one》2016,11(3)
Objective
To investigate whether exhaled breath analysis using an electronic nose can identify differences between inflammatory joint diseases and healthy controls.Methods
In a cross-sectional study, the exhaled breath of 21 rheumatoid arthritis (RA) and 18 psoriatic arthritis (PsA) patients with active disease was compared to 21 healthy controls using an electronic nose (Cyranose 320; Smiths Detection, Pasadena, CA, USA). Breathprints were analyzed with principal component analysis, discriminant analysis, and area under curve (AUC) of receiver operating characteristics (ROC) curves. Volatile organic compounds (VOCs) were identified by gas chromatography and mass spectrometry (GC-MS), and relationships between breathprints and markers of disease activity were explored.Results
Breathprints of RA patients could be distinguished from controls with an accuracy of 71% (AUC 0.75, 95% CI 0.60–0.90, sensitivity 76%, specificity 67%). Breathprints from PsA patients were separated from controls with 69% accuracy (AUC 0.77, 95% CI 0.61–0.92, sensitivity 72%, specificity 71%). Distinction between exhaled breath of RA and PsA patients exhibited an accuracy of 69% (AUC 0.72, 95% CI 0.55–0.89, sensitivity 71%, specificity 72%). There was a positive correlation in RA patients of exhaled breathprints with disease activity score (DAS28) and number of painful joints. GC-MS identified seven key VOCs that significantly differed between the groups.Conclusions
Exhaled breath analysis by an electronic nose may play a role in differential diagnosis of inflammatory joint diseases. Data from this study warrant external validation. 相似文献7.
Socioeconomic status and anthropometric changes—A meta‐analytic approach from seven German cohorts
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Johannes Haerting Saskia Hartwig Daniel Tiller Daniel Medenwald Susanne Vogt Barbara Thorand Rolf Holle Ursula Bachlechner Heiner Boeing Benedikt Merz Ute Nöthlings Sabrina Schlesinger Sabine Schipf Till Ittermann Nicole Aumann Anja Schienkiewitz Marjolein Haftenberger Karin H. Greiser Jasmine Neamat‐Allah Verena Katzke Alexander Kluttig 《Obesity (Silver Spring, Md.)》2016,24(3):710-718
8.
Marjolein M. Eysink Smeets Roeland B. van Leeuwen Raymond van de Berg 《Tijdschrift voor gerontologie en geriatrie》2016,47(1):9-15
Balance disorders in the elderly often have several contributing causes. The search for these causes focuses on vision, proprioception, coordination and medication. The peripheral vestibular system is often overlooked. This is probably due to the fact that most clinicians overlook the vestibular system, when complaints of vertigo are missing. However, dysfunction of the vestibular system may cause imbalance without vertigo. Three cases are presented. One case illustrates several contributing causes leading to imbalance. Two other cases illustrate causes of vestibular dysfunction resulting in imbalance without vertigo: a bilateral vestibulopathy and benign paroxysmal positional vertigo. Symptoms, examination and treatment are discussed. All patients with imbalance should undergo a Head Impulse Test and Dix-Hallpike maneuver. 相似文献
9.
Tomato spotted wilt virus glycoproteins exhibit trafficking and localization signals that are functional in mammalian cells
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![点击此处可从《Journal of virology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The glycoprotein precursor (G1/G2) gene of tomato spotted wilt virus (TSWV) was expressed in BHK cells using the Semliki Forest virus expression system. The results reveal that in this cell system, the precursor is efficiently cleaved and the resulting G1 and G2 glycoproteins are transported from the endoplasmic reticulum (ER) to the Golgi complex, where they are retained, a process that could be blocked by tunicamycin. Expression of G2 alone resulted in transport to and retention in the Golgi complex, albeit less efficient, suggesting that G2 contains a Golgi retention signal. G1 alone was retained in the ER, irrespective of whether it contained the precursor's signal sequence or its own N-terminal hydrophobic sequence. Coexpression of G1 and G2 from separate gene constructs resulted in rescue of efficient G1 transport, as the proteins coaccumulated in the Golgi complex, indicating that their interaction is essential for proper targeting to this organelle. The results demonstrate that transport and targeting of the plant TSWV glycoproteins in mammalian BHK cells are strikingly similar to those of animal-infecting bunyavirus glycoproteins in mammalian cells. The observations are likely to reflect the dual tropism of TSWV, which replicates both in its plant host and in its animal (thrips) vector. 相似文献
10.
Comprehensive detection of genomic duplications and deletions in the DMD gene,by use of multiplex amplifiable probe hybridization 总被引:20,自引:0,他引:20
White S Kalf M Liu Q Villerius M Engelsma D Kriek M Vollebregt E Bakker B van Ommen GJ Breuning MH den Dunnen JT 《American journal of human genetics》2002,71(2):365-374
Duplications and deletions are known to cause a number of genetic disorders, yet technical difficulties and financial considerations mean that screening for these mutations, especially duplications, is often not performed. We have adapted multiplex amplifiable probe hybridization (MAPH) for the screening of the DMD gene, mutations in which cause Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy. MAPH involves the quantitative recovery of specifically designed probes following hybridization to immobilized genomic DNA. We have engineered probes for each of the 79 exons of the DMD gene, and we analyzed them by using a 96-capillary sequencer. We screened 24 control individuals, 102 patients, and 23 potential carriers and detected a large number of novel rearrangements, especially small, one- and two-exon duplications. A duplication of exon 2 alone was the most frequently occurring mutation identified. Our analysis indicates that duplications occur in 6% of patients with DMD. The MAPH technique as modified here is simple, quick, and accurate; furthermore, it is based on existing technology (i.e., hybridization, PCR, and electrophoresis) and should not require new equipment. Together, these features should allow easy implementation in routine diagnostic laboratories. Furthermore, the methodology should be applicable to any genetic disease, it should be easily expandable to cover >200 probes, and its characteristics should facilitate high-throughput screening. 相似文献