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71.
Vanessa Scanlon Do Yu Soung Naga Suresh Adapala Elise Morgan Marc F. Hansen Hicham Drissi Archana Sanjay 《PloS one》2015,10(9)
Mice in which Cbl is unable to bind PI3K (YF mice) display increased bone volume due to enhanced bone formation and repressed bone resorption during normal bone homeostasis. We investigated the effects of disrupted Cbl-PI3K interaction on fracture healing to determine whether this interaction has an effect on bone repair. Mid-diaphyseal femoral fractures induced in wild type (WT) and YF mice were temporally evaluated via micro-computed tomography scans, biomechanical testing, histological and histomorphometric analyses. Imaging analyses revealed no change in soft callus formation, increased bony callus formation, and delayed callus remodeling in YF mice compared to WT mice. Histomorphometric analyses showed significantly increased osteoblast surface per bone surface and osteoclast numbers in the calluses of YF fractured mice, as well as increased incorporation of dynamic bone labels. Furthermore, using laser capture micro-dissection of the fracture callus we found that cells lacking Cbl-PI3K interaction have higher expression of Osterix, TRAP, and Cathepsin K. We also found increased expression of genes involved in propagating PI3K signaling in cells isolated from the YF fracture callus, suggesting that the lack of Cbl-PI3K interaction perhaps results in enhanced PI3K signaling, leading to increased bone formation, but delayed remodeling in the healing femora. 相似文献
72.
Said El?Shamieh Marion Neuillé Angélique Terray Elise Orhan Christel Condroyer Vanessa Démontant Christelle Michiels Aline Antonio Fiona Boyard Marie-Elise Lancelot Mélanie Letexier Jean-Paul Saraiva Thierry Léveillard Saddek Mohand-Sa?d Olivier Goureau José-Alain Sahel Christina Zeitz Isabelle Audo 《American journal of human genetics》2014,94(4):625-633
73.
Jessica L. Burpee Elise L. Bardsley Richard M. Dillaman Wade O. Watanabe Stephen T. Kinsey 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2010,180(7):967-977
White muscle (WM) fibers in many fishes often increase in size from <50 μm in juveniles to >250 μm in adults. This leads to
increases in intracellular diffusion distances that may impact the scaling with body mass of muscle metabolism. We have previously
found similar negative scaling of aerobic capacity (mitochondrial volume density, V
mt) and the rate of an aerobic process (post-contractile phosphocreatine recovery) in fish WM. In the present study, we examined
the scaling with body mass of oxygen consumption rates of isolated mitochondria (VO2mt) from WM in three species from different families that vary in morphology and behavior: an active, pelagic species (bluefish,
Pomatomus saltatrix), a relatively inactive demersal species (black sea bass, Centropristis striata), and a sedentary, benthic species (southern flounder, Paralichthys lethostigma). In contrast to our prior studies, the measurement of respiration in isolated mitochondria is not influenced by the diffusion
of oxygen or metabolites. V
mt was measured in WM and in high-density isolates used for VO2mt measurements. WM V
mt was significantly higher in the bluefish than in the other two species and VO2mt was independent of body mass when expressed per milligram protein or per milliliter mitochondria. The size-independence of
VO2mt indicates that differences in WM aerobic function result from variation in V
mt and not to changes in VO2mt. This is consistent with our prior work that indicated that while diffusion constraints influence mitochondrial distribution,
the negative scaling of aerobic processes like post-contractile PCr recovery can largely be attributed to the body size dependence
of V
mt. 相似文献
74.
75.
Mireia Martín-Satué Elise G. Lavoie Michel Fausther Joanna Lecka Elisabet Aliagas Filip Kukulski Jean Sévigny 《Histochemistry and cell biology》2010,133(6):659-668
Extracellular ATP and its hydrolysis product adenosine modulate various reproductive functions such as those requiring contraction,
steroidogenesis, and maintenance of fluid composition. Interestingly, adenosine might act as a key capacitative effector for
mammalian spermatozoa to acquire the capacity for fertilisation. Extracellular nucleotide levels are affected by cell surface
ectonucleotidases, amongst which the ectonucleoside triphosphate diphosphohydrolase (E-NTPDase) family regroups the most abundant
and effective enzymes to hydrolyse ATP and ADP to AMP in physiological conditions. In the male reproductive tract three members
of this family have been indentified: NTPDase1, NTPDase2 and NTPDase3 (Martín-Satué et al. in Histochem Cell Biol 131:615–628,
2009). The purpose of the present study was to characterize in the male reproductive tract the expression profile of the main
enzyme responsible for the generation of adenosine from AMP, namely the ecto-5′-nucleotidase (CD73). The enzyme was identified
by immunological techniques and by in situ enzymatic assays, including inhibition experiments with α,β-methylene-ADP, a specific
CD73 inhibitor. High levels of ecto-5′-nucleotidase were detected in testes in association with both germinal and somatic
cells, in smooth muscle cells throughout the tract, in secretory epithelia from exocrine glands, and remarkably, in principal
cells of epididymis, where co-localization with NTPDase3 was found. The relevance of this co-expression on nucleotide hydrolysis
in these cells directly involved in the control of sperm fluid composition was addressed biochemically. This study suggests
close regulation of extracellular nucleoside and nucleotide levels in the genital tract by ecto-5′-nucleotidase that, in concurrence
with NTPDases, may impact male fertility. 相似文献
76.
Beaulieu C Isabel E Fortier A Massé F Mellon C Méthot N Ndao M Nicoll-Griffith D Lee D Park H Black WC 《Bioorganic & medicinal chemistry letters》2010,20(24):7444-7449
Identification of potent and reversible cruzipain inhibitors for the treatment of Chagas disease is described. The identified inhibitors bearing an amino nitrile warhead in P1 exhibit low nanomolar in vitro potency against cruzipain. Further SAR in P2 portion led to the identification of compounds, such as 26, that have a unique selectivity profile against other cysteine proteases and offering new opportunities for safer treatment of Chagas disease. 相似文献
77.
The identification of new diagnostic or prognostic biomarkers is one of the main aims of clinical cancer research. In recent years, there has been a growing interest in using mass spectrometry for the detection of such biomarkers. The MS signal resulting from MALDI‐TOF measurements is contaminated by different sources of technical variations that can be removed by a prior pre‐processing step. In particular, denoising makes it possible to remove the random noise contained in the signal. Wavelet methodology associated with thresholding is usually used for this purpose. In this study, we adapted two multivariate denoising methods that combine wavelets and PCA to MS data. The objective was to obtain better denoising of the data so as to extract the meaningful proteomic biological information from the raw spectra and reach meaningful clinical conclusions. The proposed methods were evaluated and compared with the classical soft thresholding denoising method using both real and simulated data sets. It was shown that taking into account common structures of the signals by adding a dimension reduction step on approximation coefficients through PCA provided more effective denoising when combined with soft thresholding on detail coefficients. 相似文献
78.
79.
Xiuyan Huo Elise Schnabel Kelley Hughes Julia Frugoli 《Journal of Plant Growth Regulation》2006,25(2):156-165
The symbiosis between legumes and rhizobia results in the development of a new plant organ, the nodule. A role for polar auxin
transport in nodule development in Medicago truncatula has been demonstrated using molecular genetic tools. The expression of a DR5::GUS auxin-responsive promoter in uninoculated
M. truncatula roots mirrored that reported in Arabidopsis, and expression of the construct in nodulating roots confirmed results reported in white clover. The localization of a root-specific
PIN protein (MtPIN2) in normal roots, developing lateral roots and nodules provided the first evidence that a PIN protein is expressed in
nodules. Reduced levels of MtPIN2, MtPIN3, and MtPIN4 mRNAs via RNA interference demonstrated that plants with reduced expression of various MtPINs display a reduced number of
nodules. The reported results show that in M. truncatula, PIN proteins play an important role in nodule development, and that nodules and lateral roots share some early auxin responses
in common, but they rapidly differentiate with respect to auxin and MtPIN2 protein distribution. 相似文献
80.
Elise Huchard Alice Baniel Susanne Schliehe‐Diecks Peter M. Kappeler 《Molecular ecology》2013,22(15):4071-4086
Sexual selection theory suggests that choice for partners carrying dissimilar genes at the major histocompatibility complex (MHC) may play a role in maintaining genetic variation in animal populations by limiting inbreeding or improving the immunity of future offspring. However, it is often difficult to establish whether the observed MHC dissimilarity among mates drives mate choice or represents a by‐product of inbreeding avoidance based on MHC‐independent cues. Here, we used 454‐sequencing and a 10‐year study of wild grey mouse lemurs (Microcebus murinus), small, solitary primates from western Madagascar, to compare the relative importance on the mate choice of two MHC class II genes, DRB and DQB, that are equally variable but display contrasting patterns of selection at the molecular level, with DRB under stronger diversifying selection. We further assessed the effect of the genetic relatedness and of the spatial distance among candidate mates on the detection of MHC‐dependent mate choice. Our results reveal inbreeding avoidance, along with disassortative mate choice at DRB, but not at DQB. DRB‐disassortative mate choice remains detectable after excluding all related dyads (characterized by a relatedness coefficient r > 0), but varies slightly with the spatial distance among candidate mates. These findings suggest that the observed deviations from random mate choice at MHC are driven by functionally important MHC genes (like DRB) rather than passively resulting from inbreeding avoidance and further emphasize the need for taking into account the spatial and genetic structure of the population in correlative tests of MHC‐dependent mate choice. 相似文献