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Bone morphogenetic proteins are members of the transforming growth factor-beta superfamily that have multiple functions in the developing nervous system. One of them, bone morphogenetic protein-2 (BMP-2), promotes the differentiation of cultured striatal neurones, enhancing dendrite growth and calbindin-positive phenotype. Bone morphogenetic proteins have been implicated in cooperative interactions with other neurotrophic factors. Here we examined whether the effects of BMP-2 on cultured striatal neurones are mediated or enhanced by other neurotrophic factors. BMP-2 had a cooperative effect with low doses of brain-derived neurotrophic factor or neurotrophin-3 (but not with other neurotrophic factors such as glial cell line-derived neurotrophic factor, neurturin or transforming growth factor-beta 2) on the number of calbindin-positive striatal neurones. Moreover, BMP-2 induced phosphorylated Trk immunoreactivity in cultured striatal neurones, suggesting that neurotrophins are involved in BMP-2 neurotrophic effects. The addition of TrkB-IgG or antibodies against brain-derived neurotrophic factor abolished the effects of BMP-2 on the number and degree of differentiation of calbindin-positive striatal neurones. Indeed, BMP-2 treatment increased brain-derived neurotrophic factor protein levels in treated cultures media and BDNF immunocytochemistry revealed that this neurotrophin was produced by neuronal cells. Taken together, these results indicate that brain-derived neurotrophic factor mediates the effects of BMP-2 on striatal neurones. 相似文献
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X. Yin E. Griesshaber A. Checa F. Nindiyasari-Behal I. Sánchez-Almazo A. Ziegler W.W. Schmahl 《Journal of structural biology》2021,213(2):107707
Shells of calcifying foraminifera play a major role in marine biogeochemical cycles; fossil shells form important archives for paleoenvironment reconstruction. Despite their importance in many Earth science disciplines, there is still little consensus on foraminiferal shell mineralization. Geochemical, biochemical, and physiological studies showed that foraminiferal shell formation might take place through various and diverse mineralization mechanisms.In this study, we contribute to benthic foraminiferal shell calcification through deciphering crystallite organization within the shells. We base our conclusions on results gained from electron backscattered diffraction (EBSD) measurements and describe microstructure/texture characteristics within the laminated shell walls of the benthic, symbiontic foraminifera: Ammonia tepida, Amphistegina lobifera, Amphistegina lessonii. We highlight crystallite assembly patterns obtained on differently oriented cuts and discuss crystallite sizes, morphologies, interlinkages, orientations, and co-orientation strengths.We show that: (i) crystals within benthic foraminiferal shells are mesocrystals, (ii) have dendritic-fractal morphologies and (iii) interdigitate strongly. Based on crystal size, we (iv) differentiate between the two layers that comprise the shells and demonstrate that (v) crystals in the septa have different assemblies relative to those in the shell walls. We highlight that (vi) at junctions of different shell elements the axis of crystal orientation jumps abruptly such that their assembly in EBSD maps has a bimodal distribution. We prove (vii) extensive twin-formation within foraminiferal calcite; we demonstrate (viii) the presence of two twin modes: 60°/[0 0 1] and 77°/~[6 –6 1] and visualize their distributions within the shells.In a broader perspective, we draw conclusions on processes that lead to the observed microstructure/texture patterns. 相似文献
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In coastal cliffs consisting of Pliocene fine‐grained clastic sediments at El Rompido, Huelva, Spain we discovered around the high water line an extensive zone of about 1.5 m in height burrows that were made by up to 4 mm long isopods Paragnathia formica (Hesse) and small 5 mm long staphylinid beetles (Bledius cf. corniger Rosenhauer). The burrowing zone was crowded with irregular burrows 2–5 mm in diameter and extended some 5 cm deep in the cliff. The base of the cliff showed a clear (bio)erosional notch due to this burrowing activity, comparable to those produced by marine boring and scraping organisms in, for example, calcareous rocks. This indicates that the activity of Paragnathia and Bledius helps in eroding the cliffs, a phenomenon not published earlier as far as we know. A comparable but less extensive burrowed zone was found farther upstream near Cartaya. Their presence around the high tide zone also might prove these burrows to be good markers of former high tide lines in older cliffs. 相似文献
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Danilo ML Prado Fabiana B Benatti Ana L de Sá-Pinto Ana P Hayashi Bruno Gualano Rosa MR Pereira Adriana ME Sallum Eloisa Bonfá Clovis A Silva Hamilton Roschel 《Arthritis research & therapy》2013,15(2):R46
Introduction
Exercise training has emerged as a promising therapeutic strategy to counteract physical dysfunction in adult systemic lupus erythematosus. However, no longitudinal studies have evaluated the effects of an exercise training program in childhood-onset systemic lupus erythematosus (C-SLE) patients. The objective was to evaluate the safety and the efficacy of a supervised aerobic training program in improving the cardiorespiratory capacity in C-SLE patients.Methods
Nineteen physically inactive C-SLE patients were randomly assigned into two groups: trained (TR, n = 10, supervised moderate-intensity aerobic exercise program) and non-trained (NT, n = 9). Gender-, body mass index (BMI)- and age-matched healthy children were recruited as controls (C, n = 10) for baseline (PRE) measurements only. C-SLE patients were assessed at PRE and after 12 weeks of training (POST). Main measurements included exercise tolerance and cardiorespiratory measurements in response to a maximal exercise (that is, peak VO2, chronotropic reserve (CR), and the heart rate recovery (ΔHRR) (that is, the difference between HR at peak exercise and at both the first (ΔHRR1) and second (ΔHRR2) minutes of recovery after exercise).Results
The C-SLE NT patients did not present changes in any of the cardiorespiratory parameters at POST (P > 0.05). In contrast, the exercise training program was effective in promoting significant increases in time-to-exhaustion (P = 0.01; ES = 1.07), peak speed (P = 0.01; ES = 1.08), peak VO2 (P = 0.04; ES = 0.86), CR (P = 0.06; ES = 0.83), and in ΔHRR1 and ΔHRR2 (P = 0.003; ES = 1.29 and P = 0.0008; ES = 1.36, respectively) in the C-SLE TR when compared with the NT group. Moreover, cardiorespiratory parameters were comparable between C-SLE TR patients and C subjects after the exercise training intervention, as evidenced by the ANOVA analysis (P > 0.05, TR vs. C). SLEDAI-2K scores remained stable throughout the study.Conclusion
A 3-month aerobic exercise training was safe and capable of ameliorating the cardiorespiratory capacity and the autonomic function in C-SLE patients.Trial registration
NCT01515163. 相似文献7.
Emilie M. M. Santos Wiro J. Niessen Albert J. Yoo Olvert A. Berkhemer Ludo F. Beenen Charles B. Majoie Henk. A. Marquering MR CLEAN investigators 《PloS one》2016,11(1)
Background and Purpose
In acute ischemic stroke (AIS) management, CT-based thrombus density has been associated with treatment success. However, currently used thrombus measurements are prone to inter-observer variability and oversimplify the heterogeneous thrombus composition. Our aim was first to introduce an automated method to assess the entire thrombus density and then to compare the measured entire thrombus density with respect to current standard manual measurements.Materials and Method
In 135 AIS patients, the density distribution of the entire thrombus was determined. Density distributions were described using medians, interquartile ranges (IQR), kurtosis, and skewedness. Differences between the median of entire thrombus measurements and commonly applied manual measurements using 3 regions of interest were determined using linear regression.Results
Density distributions varied considerably with medians ranging from 20.0 to 62.8 HU and IQRs ranging from 9.3 to 55.8 HU. The average median of the thrombus density distributions (43.5 ± 10.2 HU) was lower than the manual assessment (49.6 ± 8.0 HU) (p<0.05). The difference between manual measurements and median density of entire thrombus decreased with increasing density (r = 0.64; p<0.05), revealing relatively higher manual measurements for low density thrombi such that manual density measurement tend overestimates the real thrombus density.Conclusions
Automatic measurements of the full thrombus expose a wide variety of thrombi density distribution, which is not grasped with currently used manual measurement. Furthermore, discrimination of low and high density thrombi is improved with the automated method. 相似文献8.
Towards a framework for the evolutionary genomics of Kinetoplastids: what kind of data and how much?
The current status of kinetoplastids phylogeny and evolution is discussed in view of the recent progresses on genomics. Some ideas on a potential framework for the evolutionary genomics of kinetoplastids are presented. 相似文献
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Carlier SG Coen VL Sabaté M Kay IP Ligthart JM Van Der Giessen WJ Levendag PC Bom K Serruys PW 《International journal of cardiovascular interventions》2000,3(1):3-12
Intracoronary brachytherapy has recently emerged as a new therapy to prevent restenosis. Initial experimental work was achieved in animal models and the results were assessed by histomorphometry. Initial clinical trials used angiography to guide dosimetry and to assess efficacy. Intravascular ultrasound (IVUS) permits tomographic examination of the vessel wall, elucidating the true morphology of the lumen and transmural components, which cannot be investigated on the lumenogram obtained by angiography. This paper reviews the use of IVUS in the clinical studies of brachytherapy conducted to date. IVUS allows clinicians to make a thorough assessment of the remodeling of the vessel and appears to have a major role to play in facilitating understanding of the underlying mechanisms of action in this emerging field. The authors propose that state-of-the-art IVUS techniques should be employed to further knowledge of the mechanisms of action of brachytherapy in atherosclerotic human coronary arteries. 相似文献
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