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61.
Ariane Germeyer Michael von Wolff Julia Jauckus Thomas Strowitzki Tanuj Sharma Anna T Grazul-Bilska 《Reproductive biology and endocrinology : RB&E》2010,8(1):67
Background
Reproductive failure, determined as recurrent spontaneous abortions (RSA) or recurrent implantation failure (RIF) in women is not well understood. Several factors, including embryo quality, and cellular and molecular changes in endometrium may contribute to the insufficient feto-maternal interaction resulting in reproductive failure. Prior clinical studies suggest an inadequate endometrial growth and development of the endometrium, leading to a lesser endometrial thickness. 相似文献62.
New insights into the unique structure of the F0F1-ATP synthase from the chlamydomonad algae Polytomella sp. and Chlamydomonas reinhardtii
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In this study, we investigate the structure of the mitochondrial F(0)F(1)-ATP synthase of the colorless alga Polytomella sp. with respect to the enzyme of its green close relative Chlamydomonas reinhardtii. It is demonstrated that several unique features of the ATP synthase in C. reinhardtii are also present in Polytomella sp. The alpha- and beta-subunits of the ATP synthase from both algae are highly unusual in that they exhibit extensions at their N- and C-terminal ends, respectively. Several subunits of the Polytomella ATP synthase in the range of 9 to 66 kD have homologs in the green alga but do not have known equivalents as yet in mitochondrial ATP synthases of mammals, plants, or fungi. The largest of these so-called ASA (ATP Synthase-Associated) subunits, ASA1, is shown to be an extrinsic protein. Short heat treatment of isolated Polytomella mitochondria unexpectedly dissociated the otherwise highly stable ATP synthase dimer of 1,600 kD into subcomplexes of 800 and 400 kD, assigned as the ATP synthase monomer and F(1)-ATPase, respectively. Whereas no ASA subunits were found in the F(1)-ATPase, all but two were present in the monomer. ASA6 (12 kD) and ASA9 (9 kD), predicted to be membrane bound, were not detected in the monomer and are thus proposed to be involved in the formation or stabilization of the enzyme. A hypothetical configuration of the Chlamydomonad dimeric ATP synthase portraying its unique features is provided to spur further research on this topic. 相似文献
63.
Thyroid Hormones Reorganize the Cytoskeleton of Glial Cells Through Gfap Phosphorylation and Rhoa-Dependent Mechanisms 总被引:1,自引:0,他引:1
Zamoner A Funchal C Jacques-Silva MC Gottfried C Barreto Silva FR Pessoa-Pureur R 《Cellular and molecular neurobiology》2007,27(7):845-865
Thyroid hormones (3,5,3′-triiodo-l-thyronine, T3; 3,5,3′,5′-l-tetraiodothyronine, T4; TH) play crucial roles in the growth and differentiation of the central nervous system. In this study, we investigated the
actions of TH on proliferation, viability, cell morphology, in vitro phosphorylation of glial fibrillary acidic protein (GFAP)
and actin reorganization in C6 glioma cells. We first observe that long-term exposure to TH stimulates cell proliferation
without induce cell death. We also demonstrate that after 3, 6, 12, 18, and 24 h treatment with TH, C6 cells and cortical
astrocytes show a process-bearing shape. Furthermore, immunocytochemistry with anti-actin and anti-GFAP antibodies reveals
that TH induces reorganization of actin and GFAP cytoskeleton. We also observe an increased in vitro 32P incorporation into GFAP recovered into the high-salt Triton insoluble cytoskeletal fraction after 3 and 24 h exposure to
5×10−8 and 10−6 M T3, and only after 24 h exposure to 10−9 M T4. These results show a T3 action on the phosphorylating system associated to GFAP and suggest a T3-independent effect of T4 on this cytoskeletal protein. In addition, C6 cells and astrocytes treated with lysophosphatidic acid, an upstream activator
of the RhoA GTPase pathway, totally prevented the morphological alterations induced by TH, indicating that this effect could
be mediated by the RhoA signaling pathway. Considering that IF network can be regulated by phosphorylation leading to reorganization
of IF filamentous structure and that alterations of the microfilament organization may have important implications in glial
functions, the effects of TH on glial cell cytoskeleton could be implicated in essential neural events such as brain development. 相似文献
64.
Arbuscular mycorrhizal fungi can induce the production of phytochemicals in sweet basil irrespective of phosphorus nutrition 总被引:3,自引:0,他引:3
The potential of three arbuscular mycorrhizal fungi (AMF) to enhance the production of antioxidants (rosmarinic and caffeic
acids, RA and CA) was investigated in sweet basil (Ocimum basilicum). After adjusting phosphorus (P) nutrition so that P concentrations and yield were matched in AM and non-mycorrhizal (NM)
plants we demonstrated that Glomus caledonium increased RA and CA production in the shoots. Glomus mosseae also increased shoot CA concentration in basil under similar conditions. Although higher P amendments to NM plants increased
RA and CA concentrations, there was higher production of RA and CA in the shoots of AM plants, which was not solely due to
better P nutrition. Therefore, AMF potentially represent an alternative way of promoting growth of this important medicinal
herb, as natural ways of growing such crops are currently highly sought after in the herbal industry. 相似文献
65.
66.
L. Allard A. Toussaint R. Vigouroux S. Brosse 《Zeitschrift fur angewandte Ichthyologie》2015,31(3):567-570
Length‐weight relationship parameters of the form W = aLb are presented for 58 fish species representing 36 genus and 19 families captured in streams of French Guiana. LWRs for 53 of the species are estimated for the first time. 相似文献
67.
68.
Marion Nicolaus Kimberley J. Mathot Yimen G. Araya-Ajoy Ariane Mutzel Jan J. Wijmenga Bart Kempenaers Niels J. Dingemanse 《Proceedings. Biological sciences / The Royal Society》2015,282(1799)
A number of studies have suggested that avian brood size is individually optimized. Yet, optimal reproductive decisions likely vary owing to among-individual differences in environmental sensitivity. Specifically, ‘proactive’ individuals who do not track environmental changes may be less able to produce optimal brood sizes than ‘reactive’ individuals who have more precise local environmental knowledge. To test this, we quantified exploratory behaviour (a proxy for proactivity) in a great tit (Parus major) population, manipulated brood sizes (reduced, control, enlarged) and evaluated whether individuals of dissimilar coping style differed in their level of optimization. If reactive females behaved optimally, any deviation from their original brood size should lower fitness, whereas this should not be the case for proactive females. Reactive females indeed performed best at their natural brood size, whereas proactive females performed best when raising an enlarged brood. These findings imply that proactive females produced sub-optimal brood sizes. We speculate that proactive females might (i) take decisions based on biased perception of their environment, (ii) face energetic constraints in offspring production and/or (iii) be more willing to invest into current reproduction when given the option. Our findings provide experimental evidence for coping style-related differences in optimal reproductive decisions and life-history strategies. 相似文献
69.
70.
Jeffrey J. Perry Mukul Sharma Marco L.A. Sivilotti Jane Sutherland Cheryl Symington Andrew Worster Marcel ��mond Grant Stotts Albert Y. Jin Weislaw J. Oczkowski Demetrios J. Sahlas Heather E. Murray Ariane MacKey Steve Verreault George A. Wells Ian G. Stiell 《CMAJ》2011,183(10):1137-1145