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101.
102.
This study covers a fifty-year period between 1953 and 2005 and looks at secular trends in stature, weight and sitting height sizes among French boys and girls between the ages of 3 and 11. A special modelling in function to the age and variable for each child was established so that a comparison could be made in the kinetic growth patterns over these same two periods. Statistical analysis shows a significant increase in growth, of 0.8cm per decade in stature, characterised by a certain increase in the lower limbs and the weight (0.8kg per decade) together with a proportional increase on the body mass index. Positive secular trends of this anthropometric nature are generally thanks to improved eating and sanitary habits and this study enables us to build and elaborate new standards in growth patterns essential for monitoring auxological development in 3 to 11-year-old children in the years 2000 and onwards.  相似文献   
103.
For influenza viruses to become infectious, the proteolytic cleavage of hemagglutinin (HA) is essential. This usually is mediated by trypsin-like proteases in the respiratory tract. The binding of plasminogen to influenza virus A/WSN/33 leads to the cleavage of HA, a feature determining its pathogenicity and neurotropism in mice. Here, we demonstrate that plasminogen also promotes the replication of other influenza virus strains. The inhibition of the conversion of plasminogen into plasmin blocked influenza virus replication. Evidence is provided that the activation of plasminogen is mediated by the host cellular protein annexin II, which is incorporated into the virus particles. Indeed, the inhibition of plasminogen binding to annexin II by using a competitive inhibitor inhibits plasminogen activation into plasmin. Collectively, these results indicate that the annexin II-mediated activation of plasminogen supports the replication of influenza viruses, which may contribute to their pathogenicity.  相似文献   
104.
Clinical findings in vitiligo challenge the widely accepted organ specific autoimmune pathomechanisms. We draw the attention to the fact that the distribution of segmental vitiligo (SV) fits in at least a subset of patients a pattern usually associated with cutaneous mosaicism. The association of SV to non-segmental vitiligo (NSV) now confirmed by several observations indicates a continuum between the two subsets with shared predisposing genetic factors, including genes operating specifically in the skin. Some pedigrees associating SV and NSV further suggest a mechanism of loss of heterozygosity for a dominant gene controlling part of the cutaneous phenotype. The mosaic hypothesis applies only to SV and to the rare SV-NSV association, but suggests that predisposing genetic factors in common NSV should also be searched directly in the skin. SV would be a good candidate disease to explore as a proof of principle of a new gene discovery strategy useful for multigenic disorders with organ specificity, applicable in priority to chronic inflammatory skin disorders.  相似文献   
105.
ASAP3, an Arf GTPase-activating protein previously called DDEFL1 and ACAP4, has been implicated in the pathogenesis of hepatocellular carcinoma. We have examined in vitro and in vivo functions of ASAP3 and compared it to the related Arf GAP ASAP1 that has also been implicated in oncogenesis. ASAP3 was biochemically similar to ASAP1: the pleckstrin homology domain affected function of the catalytic domain by more than 100-fold; catalysis was stimulated by phosphatidylinositol 4,5-bisphosphate; and Arf1, Arf5, and Arf6 were used as substrates in vitro. Like ASAP1, ASAP3 associated with focal adhesions and circular dorsal ruffles. Different than ASAP1, ASAP3 did not localize to invadopodia or podosomes. Cells, derived from a mammary carcinoma and from a glioblastoma, with reduced ASAP3 expression had fewer actin stress fiber, reduced levels of phosphomyosin, and migrated more slowly than control cells. Reducing ASAP3 expression also slowed invasion of mammary carcinoma cells. In contrast, reduction of ASAP1 expression had no effect on migration or invasion. We propose that ASAP3 functions nonredundantly with ASAP1 to control cell movement and may have a role in cancer cell invasion. In comparing ASAP1 and ASAP3, we also found that invadopodia are dispensable for the invasive behavior of cells derived from a mammary carcinoma.  相似文献   
106.
107.
Two mutants of Chlamydomonas reinhardtii, mf1 and mf2, characterized by a marked reduction in their phosphatidylglycerol content together with a complete loss in its Delta3-trans hexadecenoic acid-containing form, also lost photosystem II (PSII) activity. Genetic analysis of crosses between mf2 and wild-type strains shows a strict cosegregation of the PSII and lipid deficiencies, while phenotypic analysis of phototrophic revertant strains suggests that one single nuclear mutation is responsible for the pleiotropic phenotype of the mutants. The nearly complete absence of PSII core is due to a severely decreased synthesis of two subunits, D1 and apoCP47, which is not due to a decrease in translation initiation. Trace amounts of PSII cores that were detected in the mutants did not associate with the light-harvesting chlorophyll a/b-binding protein antenna (LHCII). We discuss the possible role of phosphatidylglycerol in the coupled process of cotranslational insertion and assembly of PSII core subunits.  相似文献   
108.
109.
Integrity of epithelial tissues relies on the proper apical-basolateral polarity of epithelial cells. Members of the LAP (LRR and PDZ) protein family such as LET-413 and Scribble are involved in maintaining epithelial cell polarity in Caenorhabditis elegans and Drosophila melanogaster, respectively. We previously described Erbin as a mammalian LET-413 homologue interacting with ERBB2/HER2, an epidermal growth factor receptor family member. Erbin and ERBB2/HER2 are located in the basolateral membranes of epithelial cells. We show here that Erbin interacts with p0071 (also called plakophilin-4), an armadillo repeat protein linked to the cytoskeleton. Erbin binds to p0071 in vitro and in vivo in a PDZ domain-dependent manner, and both proteins colocalized in desmosomes of epithelial cells. Using a dominant negative approach, we found that integrity of epithelial cell monolayer is impaired when interaction between Erbin and p0071 is disrupted. We propose that Erbin is connected by p0071 to cytoskeletal networks in an interaction crucial for epithelial homeostasis.  相似文献   
110.
The analysis of gene function during retinal development can be addressed by perturbing gene expression either by inhibition or by overexpression in desired regions and at defined stages of development. An in vivo lipofection strategy has been applied for stage-specific and region-specific expression of genes in Xenopus retina. Due to colipofection efficiency, this strategy enables us to study functional interaction of genes by lipofecting multiple expression constructs. This lipofection technique also allows us to transfect morpholino oligonucleotides into retinoblasts to block gene function. We present here various aspects of this technique, including recent improvements and modifications.  相似文献   
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