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991.
Qiao Liya Zhang Xifang Jan Catherine Li Xiaoxia Li Meng Wang Huaizhou 《中国科学:生命科学英文版》2019,62(7):930-936
Optical coherence tomography angiography(Angio-OCT) has introduced a new non-invasive, quantitative method to assess superficial and deep capillary networks of the retina. In this study, we investigated macular retinal thickness and flow density change following posterior scleral reinforcement(PSR) surgery, using an RTVue XR Avanti Angio-OCT, in patients with pathological myopia. A total of 13 patients with pathological myopia were recruited and all patients completed the 6 months follow-up visit. Data from 22 eyes were used in this study. The mean age was 36.23±15.29 years, and 43%(n=6) were men.Spherical equivalent refractive error(SE) ranged from –8.0 to –24.0 D. Postoperative axial length, best-corrected visual acuity and SE did not change significantly at each follow-up, compared with pre-operative measures(P0.05). Postoperative flow density of superficial and deep retinal layers at each sector did not change significantly at each follow-up, compared with preoperative measures(P0.05). However, we found significant decrease in retinal thickness of parafovea-inferior sector after PSR surgery(P0.01), indicating potential relaxation of vitreofoveal traction after PSR surgery. 相似文献
992.
Xuting Bian Tianyao Liu Mei Zhou Gang He Yuanyuan Ma Youxing Shi Yunjiao Wang Hong Tang Xia Kang Mingyu Yang Jan‐ke Gustafsson Xiaotang Fan Kanglai Tang 《Journal of cellular and molecular medicine》2019,23(11):7406-7416
Achilles tendon injury is one of the challenges of sports medicine, the aetiology of which remains unknown. For a long time, estrogen receptor β (ERβ) has been known as a regulating factor of the metabolism in many connective tissues, such as bone, muscle and cartilage, but little is known about its role in tendon. Recent studies have implicated ERβ as involved in the process of tendon healing. Tendon‐derived stem cells (TDSCs) are getting more and more attention in tendon physiological and pathological process. In this study, we investigated how ERβ played a role in Achilles tendon healing. Achilles tendon injury model was established to analyse how ERβ affected on healing process in vivo. Cell proliferation assay, Western blots, qRT‐PCR and immunocytochemistry were performed to investigate the effect of ERβ on TDSCs. Here, we showed that ERβ deletion in mice resulted in inferior gross appearance, histological scores and, most importantly, increased accumulation of adipocytes during the early tendon healing which involved activation of peroxisome proliferator‐activated receptor γ (PPARγ) signalling. Furthermore, in vitro results of ours confirmed that the abnormity might be the result of abnormal TDSC adipogenic differentiation which could be partially reversed by the treatment of ERβ agonist LY3201. These data revealed a role of ERβ in Achilles tendon healing for the first time, thereby providing a new target for clinical treatment of Achilles tendon injury. 相似文献
993.
Risk and essential elements were determined in fruiting bodies of wild growing edible mushrooms Chlorophyllum rhacodes, Suillus grevillei, Imleria badia, and Xerocomellus chrysenteron collected in an unpolluted site in South Bohemia, the Czech Republic. The elements were also determined in underlying soils and the bioconcentration factors were calculated. The analyses revealed that C. rhacodes accumulated Ag, Cu, Rb, Se, Zn, As, Cd, and Tl. On the other hand, S. grevillei accumulated Cd, Rb, Ag, Se, and Cs. I. badia and X. chrysenteron strongly accumulated Rb, Cs, and Ag; these species showed the ability to accumulate Cu and Zn as well. Contents of detrimental CrVI were in all cases below the quantification limit (0.003 mg kg?1 dry matter). Studied mushroom species (mainly C. rhacodes) accumulated some toxic elements. However, no considerable effect on human health is expected since they are usually consumed as a delicacy and do not represent a major component of diet. 相似文献
994.
Hennigs Jan K. Lüneburg Nicole Stage Annett Schmitz Melanie Körbelin Jakob Harbaum Lars Matuszcak Christiane Mienert Julia Bokemeyer Carsten Böger Rainer H. Kiefmann Rainer Klose Hans 《Purinergic signalling》2019,15(3):299-311
Purinergic Signalling - Dysfunction of the pulmonary endothelium is associated with most lung diseases. Extracellular nucleotides modulate a plethora of endothelial functions in the lung such as... 相似文献
995.
Henk‐Jan van den Ham Nadine A. Binai Fatiha Zaaraoui‐Boutahar Albert J. R. Heck Arno C. Andeweg 《Proteomics》2019,19(7)
Helper T cell differentiation is a key process in the regulation of adaptive immune responses. Here, mouse Th1 and Th2 cells are profiled using high‐throughput proteomics to increase the understanding of the molecular biology of Th differentiation to support the design of prophylactic and therapeutic intervention strategies for (infectious) diseases. Protein profiling of Th1/Th2 differentiated cells results in the quantification of almost 6000 proteins of which 41 are differentially expressed at FDR < 0.1, and 19 at the FDR < 0.05 level, respectively. Differential protein expression analysis identifies a number of the expected canonical Th differentiation markers, and gene set analysis using the REACTOME database and a hypergeometric test (FDR < 0.05) confirms that helper T cell pathways are the top sets that are differentially expressed. Additionally, by network analysis, many differentially expressed proteins are associated with the Th1 and Th2 pathways. Data are available via PRIDE database with identifier PXD004532. 相似文献
996.
997.
Jan M. Klenk Paulina Dubiel Mahima Sharma Gideon Grogan Bernhard Hauer 《Microbial biotechnology》2019,12(2):377-391
One of the major challenges in chemical synthesis is the selective oxyfunctionalization of non-activated C-H bonds, which can be enabled by biocatalysis using cytochrome P450 monooxygenases. In this study, we report on the characterization of the versatile CYP109Q5 from Chondromyces apiculatus DSM436, which is able to functionalize a wide range of substrates (terpenes, steroids and drugs), including the ring of β-ionone in non-allylic positions. The crystal structure of CYP109Q5 revealed flexibility within the active site pocket that permitted the accommodation of bulky substrates, and enabled a structure-guided approach to engineering the enzyme. Some variants of CYP109Q5 displayed a switch in selectivity towards the non-allylic positions of β-ionone, allowing the simultaneous production of 2- and 3-hydroxy-β-ionone, which are chemically challenging to synthesize and are important precursors for carotenoid synthesis. An efficient whole-cell system finally enabled the production of up to 0.5 g l−1 hydroxylated products of β-ionone; this system can be applied to product identification in further biotransformations. Overall, CYP109Q5 proved to be highly evolvable and active. The studies in this work demonstrate that, using rational mutagenesis, the highly versatile CYP109Q5 generalist can be progressively evolved to be an industrially valuable specialist for the synthesis of specific products. 相似文献
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999.
1000.
Sybryn L. Maes Michael P. Perring Margot Vanhellemont Leen Depauw Jan Van den Bulcke Guntis Brmelis Jrg Brunet Guillaume Decocq Jan den Ouden Werner Hrdtle Radim Hdl Thilo Heinken Steffi Heinrichs Bogdan Jaroszewicz Martin Kopecký Frantiek Mli Monika Wulf Kris Verheyen 《Global Change Biology》2019,25(1):201-217
Forecasting the growth of tree species to future environmental changes requires a better understanding of its determinants. Tree growth is known to respond to global‐change drivers such as climate change or atmospheric deposition, as well as to local land‐use drivers such as forest management. Yet, large geographical scale studies examining interactive growth responses to multiple global‐change drivers are relatively scarce and rarely consider management effects. Here, we assessed the interactive effects of three global‐change drivers (temperature, precipitation and nitrogen deposition) on individual tree growth of three study species (Quercus robur/petraea, Fagus sylvatica and Fraxinus excelsior). We sampled trees along spatial environmental gradients across Europe and accounted for the effects of management for Quercus. We collected increment cores from 267 trees distributed over 151 plots in 19 forest regions and characterized their neighbouring environment to take into account potentially confounding factors such as tree size, competition, soil conditions and elevation. We demonstrate that growth responds interactively to global‐change drivers, with species‐specific sensitivities to the combined factors. Simultaneously high levels of precipitation and deposition benefited Fraxinus, but negatively affected Quercus’ growth, highlighting species‐specific interactive tree growth responses to combined drivers. For Fagus, a stronger growth response to higher temperatures was found when precipitation was also higher, illustrating the potential negative effects of drought stress under warming for this species. Furthermore, we show that past forest management can modulate the effects of changing temperatures on Quercus’ growth; individuals in plots with a coppicing history showed stronger growth responses to higher temperatures. Overall, our findings highlight how tree growth can be interactively determined by global‐change drivers, and how these growth responses might be modulated by past forest management. By showing future growth changes for scenarios of environmental change, we stress the importance of considering multiple drivers, including past management and their interactions, when predicting tree growth. 相似文献