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81.
Romain Gastineau Gert Hansen Nikolaï A. Davidovich Olga Davidovich Jean-François Bardeau Irena Kaczmarska 《欧洲藻类学杂志》2016,51(2):156-170
Haslea provincialis Gastineau, Hansen & Mouget, sp. nov., is a new, morphologically semicryptic blue diatom discovered on the French shores of the Mediterranean Sea. Like H. ostrearia and H. karadagensis, H. provincialis shares the capacity to synthesize a marennine-like blue pigment. Sexual reproduction between clones of H. provincialis has been repeatedly observed and resulted in viable initial cells. There were no sexual interactions with sexually competent clones of H. ostrearia or H. karadagensis, as would be expected for a separate biological species. There are strong similarities between the H. provincialis pigment and the marennine produced by H. ostrearia, evidenced by UV-visible spectrophotometry and Raman spectrometry. However, unlike the marennine from H. ostrearia, no differences were found between the extracellular and the intracellular forms of the pigment in H. provincialis. This indicates that the synthesis pathways and excretion mechanisms among the three ‘blue’ Haslea may be species-specific. Molecular taxonomy and phylogeny (based on rbcL, cox1 and SSU V4 DNA sequences) confirmed the distinct position of this species among the blue Haslea species. Haslea provincialis occurs in environments from which H. ostrearia has already been reported (mostly based on the presence of the blue cell vacuoles). Possible species misidentifications and the impact of the complex geological history of the Mediterranean Sea on blue diatom diversification are also discussed. 相似文献
82.
Elizabeth Chang Sergei Pourmal Chun Zhou Rupesh Kumar Marianna Teplova Nikola P. Pavletich Kenneth J. Marians Hediye Erdjument-Bromage 《Journal of biomolecular techniques》2016,27(2):61-74
In recent history, alternative approaches to Edman sequencing have been investigated,
and to this end, the Association of Biomolecular Resource Facilities (ABRF) Protein
Sequencing Research Group (PSRG) initiated studies in 2014 and 2015, looking into
bottom-up and top-down N-terminal (Nt) dimethyl derivatization of standard quantities
of intact proteins with the aim to determine Nt sequence information. We have
expanded this initiative and used low picomole amounts of myoglobin to determine the
efficiency of Nt-dimethylation. Application of this approach on protein domains,
generated by limited proteolysis of overexpressed proteins, confirms that it is a
universal labeling technique and is very sensitive when compared with Edman
sequencing. Finally, we compared Edman sequencing and Nt-dimethylation of the same
polypeptide fragments; results confirm that there is agreement in the identity of the
Nt amino acid sequence between these 2 methods. 相似文献
83.
84.
Dominic Ehrmann Nikola Bergis-Jurgan Thomas Haak Bernhard Kulzer Norbert Hermanns 《PloS one》2016,11(1)
Background
The effectiveness of an intervention in clinical practice is often reduced compared to the efficacy demonstrated in a randomised controlled trial (RCT). In this comparative effectiveness study, the RCT-proven efficacy of a diabetes education programme for type 1 diabetic patients (PRIMAS) was compared to the effectiveness observed in an implementation trial (IT) under routine care conditions.Methods
75 patients with type 1 diabetes received PRIMAS through an RCT, whereas 179 patients were observed in an implementation trial. Baseline characteristics and treatment outcomes at the 6-month follow-up (improvement of HbA1c, hypoglycaemia problems, and diabetes-related distress) were compared.Results
At baseline, the type 1 diabetic patients in the RCT had a significant longer diabetes duration (18.7±12.3 vs. 13.8±12.7 yrs., p = .005), lower self-efficacy scores (21.9±4.7 vs. 23.7±6.1, p = .02) and a greater number of diabetes complications (0.8±1.3 vs. 0.4±0.9, p = .02). After 6 months, PRIMAS achieved comparable effects under RCT and implementation trial conditions, as demonstrated by improvement in HbA1c (-0.36%±1.1 vs. -0.37±1.2; Δ -0.01, 95% CI -0.33 to 0.31) and hypoglycaemia unawareness (-0.5±1.4 vs. -0.3±1.4; Δ 0.18, 95% CI -0.21 to 0.57). The likelihood of clinical improvement did not depend on the trial setting (RCT vs. IT: OR 1.18, 95% CI 0.60 to 2.33). The participants with worse glycaemic control (OR 1.40, 95% CI 1.02 to 1.92), hypoglycaemia problems (OR 2.13, 95% CI 1.53 to 2.97) or elevated diabetes distress (OR 1.40, 95% CI 1.03 to 1.89) had a better chance of clinical improvement.Conclusions
The effectiveness of PRIMAS under routine care conditions was comparable to the efficacy demonstrated in the RCT. Clinical improvement was independent of the setting in which PRIMAS was evaluated. The PRIMAS education programme for type 1 diabetes can be delivered under conditions of routine care without a loss of effectiveness, compared to its original evaluation in an RCT. 相似文献85.
Mario E. Giardini Antonio G. Zippo Maurizio Valente Nikola Krstajic Gabriele E. M. Biella 《PloS one》2016,11(4)
Despite the continuous improvement in medical imaging technology, visualizing the spinal cord poses severe problems due to structural or incidental causes, such as small access space and motion artifacts. In addition, positional guidance on the spinal cord is not commonly available during surgery, with the exception of neuronavigation techniques based on static pre-surgical data and of radiation-based methods, such as fluoroscopy. A fast, bedside, intraoperative real-time imaging, particularly necessary during the positioning of endoscopic probes or tools, is an unsolved issue. The objective of our work, performed on experimental rats, is to demonstrate potential intraoperative spinal cord imaging and probe guidance by optical coherence tomography (OCT). Concurrently, we aimed to demonstrate that the electromagnetic OCT irradiation exerted no particular effect at the neuronal and synaptic levels. OCT is a user-friendly, low-cost and endoscopy-compatible photonics-based imaging technique. In particular, by using a Fourier-domain OCT imager, operating at 850 nm wavelength and scanning transversally with respect to the spinal cord, we have been able to: 1) accurately image tissue structures in an animal model (muscle, spine bone, cerebro-spinal fluid, dura mater and spinal cord), and 2) identify the position of a recording microelectrode approaching and inserting into the cord tissue 3) check that the infrared radiation has no actual effect on the electrophysiological activity of spinal neurons. The technique, potentially extendable to full three-dimensional image reconstruction, shows prospective further application not only in endoscopic intraoperative analyses and for probe insertion guidance, but also in emergency and adverse situations (e.g. after trauma) for damage recognition, diagnosis and fast image-guided intervention. 相似文献
86.
Žanka Bojić-Trbojević Milica Jovanović Krivokuća Nikola Kolundžić Toshihiko Kadoya Ljiljana Radojčić 《Cell Adhesion & Migration》2016,10(1-2):179-188
ABSTRACTIn the course of embryo implantation extensive interaction of the trophoblast with uterine tissue is crucial for adequate trophoblast invasion. This interaction is highly controlled, and it has been pointed out that a specific glycocode and changes in glycosylation may be important for successful implantation and maintenance of pregnancy. Both uterine and trophoblast cells have been shown to express cell surface glycoconjugates and sugar binding proteins, such as mucins (MUC) and galectins (gals). An increasing number of studies have investigated potential candidates interacting in this process. However, knowledge about the biochemical nature of the interactions and their importance for trophoblast cell function, and, consequently, for pregnancy outcome are still lacking. This review is aimed at deliberating the possibility that mucins, as heavily glycosylated proteins, might be among the functionally relevant galectin ligands in human trophoblast, based on both published data and our original research. 相似文献
87.
Summary The organ culture technique was used for the study of early cytodifferentiation in explanted rat and mouse embryonic shields. After 15 daysin vitro the main tissues were differentiated in explants. The full differentiation depended on the presence of homologous serum in the culture medium. 95% oxygen in the atmosphere was either deleterious or without measurable effect if introduced from the beginning or toward the end of the cultivation period, respectively. Some chemically defined media supported the development for only a limited time span during the initial period of cultivation.This investigation was partly supported by NIH PL 480 Research Agreement No. 02-138-1. 相似文献
88.
89.
The action of zinc on the growth of barley and the biosynthesis of indol compounds and gibberellin-like substances was investigated in a number of concentrations of zinc from doses stimulating growth to toxic doses. The seeds were soaked before sowing in solutions of zinc sulphate (5.10?5 to 5.10?1% Zn), and the plants cultivated for 7 days in water. Lower concentrations of zinc increased both plant growth and the biosynthesis of tryptophan and auxins. At the optimum concentration of 5.10?3% Zn this increase in tryptophan amounted to 241% of the variant without zinc; in substances with an RF corresponding to indolyacetic acid, the increase determined by the biological test, was 207% as against the variant without zinc. Higher concentrations of zinc inhibited growth, the tryptophan content was decreased to below that of the control without zinc and the auxin content also fell to below the control values. Zinc also influenced the content of gibberellin-like substances in the plants. At a concentration of 5.10?3% Zn the increase in the growth activity in the gibberellic acid area of the chromatogram was 294% of the variant without zinc. At toxic concentrations of zinc, the content of gibberellin-like substances fell to below that of the controls. The finding that zinc acts simultaneously on the biosynthesis of auxins and gibberellins is also evidence for the common action of growth substances of various chemical types on plant growth. 相似文献
90.
Vedrana Milinkovic Jasna Bankovic Miodrag Rakic Tijana Stankovic Milica Skender-Gazibara Sabera Ruzdijic Nikola Tanic 《PloS one》2013,8(12)
Glioblastoma is the most frequent and malignant human brain tumor. High level of genomic instability detected in glioma cells implies that numerous genetic alterations accumulate during glioma pathogenesis. We investigated alterations in AP-PCR DNA profiles of 30 glioma patients, and detected specific changes in 11 genes not previously associated with this disease: LHFPL3, SGCG, HTR4, ITGB1, CPS1, PROS1, GP2, KCNG2, PDE4D, KIR3DL3, and INPP5A. Further correlations revealed that 8 genes might play important role in pathogenesis of glial tumors, while changes in GP2, KCNG2 and KIR3DL3 should be considered as passenger mutations, consequence of high level of genomic instability. Identified genes have a significant role in signal transduction or cell adhesion, which are important processes for cancer development and progression. According to our results, LHFPL3 might be characteristic of primary glioblastoma, SGCG, HTR4, ITGB1, CPS1, PROS1 and INPP5A were detected predominantly in anaplastic astrocytoma, suggesting their role in progression of secondary glioblastoma, while alterations of PDE4D seem to have important role in development of both glioblastoma subtypes. Some of the identified genes showed significant association with p53, p16, and EGFR, but there was no significant correlation between loss of PTEN and any of identified genes. In conclusion our study revealed genetic alterations that were not previously associated with glioma pathogenesis and could be potentially used as molecular markers of different glioblastoma subtypes. 相似文献