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71.
Background
Fetal movement counting is a method used by the mother to quantify her baby''s movements, and may prevent adverse pregnancy outcome by a timely evaluation of fetal health when the woman reports decreased fetal movements. We aimed to assess effects of fetal movement counting on identification of fetal pathology and pregnancy outcome.Methodology
In a multicentre, randomized, controlled trial, 1076 pregnant women with singleton pregnancies from an unselected population were assigned to either perform fetal movement counting from gestational week 28, or to receive standard antenatal care not including fetal movement counting (controls). Women were recruited from nine Norwegian hospitals during September 2007 through November 2009. Main outcome was a compound measure of fetal pathology and adverse pregnancy outcomes. Analysis was performed by intention-to-treat.Principal Findings
The frequency of the main outcome was equal in the groups; 63 of 433 (11.6%) in the intervention group, versus 53 of 532 (10.7%) in the control group [RR: 1.1 95% CI 0.7–1.5)]. The growth-restricted fetuses were more often identified prior to birth in the intervention group than in the control group; 20 of 23 fetuses (87.0%) versus 12 of 20 fetuses (60.0%), respectively, [RR: 1.5 (95% CI 1.0–2.1)]. In the intervention group two babies (0.4%) had Apgar scores <4 at 1 minute, versus 12 (2.3%) in the control group [RR: 0.2 (95% CI 0.04–0.7)]. The frequency of consultations for decreased fetal movement was 71 (13.1%) and 57 (10.7%) in the intervention and control groups, respectively [RR: 1.2 (95% CI 0.9–1.7)]. The frequency of interventions was similar in the groups.Conclusions
Maternal ability to detect clinically important changes in fetal activity seemed to be improved by fetal movement counting; there was an increased identification of fetal growth restriction and improved perinatal outcome, without inducing more consultations or obstetric interventions.Trial Registration
ClinicalTrials.gov NCT00513942相似文献72.
Börnke F 《Journal of plant physiology》2005,162(2):73-168
Sucrose-6-phosphate synthase (SPS) is a target for 14-3-3 protein binding in plants. Because several isoforms of the 14-3-3 protein are expressed in plants, I investigated which isoforms have the ability to bind SPS. Two 14-3-3 isoforms (T14-3d and a novel isoform designated T14-3 g) were found to interact with SPS from tobacco (Nicotiana tabacum L.) in a two-hybrid screen. To further address the question of isoform specificity of 14-3-3s, four additional isoforms were tested for their ability to interact with SPS in the yeast two-hybrid system. The results clearly revealed large differences in affinity between individual 14-3-3 isoforms toward SPS. Deletion analysis suggested that these differences were mediated by the variable C-terminus of 14-3-3s. Site-directed mutagenesis of candidate 14-3-3 binding sites on SPS demonstrated that interaction could be independent of a phosphorylated serine residue within conserved binding motifs in the yeast system. These findings suggest that the large number of 14-3-3 isoforms present in plants reflects functional specificity. 相似文献
73.
74.
Hommelgaard AM Roepstorff K Vilhardt F Torgersen ML Sandvig K van Deurs B 《Traffic (Copenhagen, Denmark)》2005,6(9):720-724
The role of caveolae in endocytosis is hotly debated. Here, we argue that most caveolae are stable microdomains at the cell surface. Only a small fraction of caveolae is constitutively internalized, leading to a quantitatively minor uptake of ligands and receptors. In addition, we suggest that a more pronounced downregulation of caveolae from the plasma membrane can occur, presumably stimulated by receptor cross-linking and clustering in caveolae. Finally, we propose that future studies dealing with internalization of caveolae should actually document such internalization and include kinetic data. 相似文献
75.
Blaney Davidson EN Scharstuhl A Vitters EL van der Kraan PM van den Berg WB 《Arthritis research & therapy》2005,7(6):R1338-R1347
Osteoarthritis (OA) is a common joint disease, mainly effecting the elderly population. The cause of OA seems to be an imbalance
in catabolic and anabolic factors that develops with age. IL-1 is a catabolic factor known to induce cartilage damage, and
transforming growth factor (TGF)-beta is an anabolic factor that can counteract many IL-1-induced effects. In old mice, we
observed reduced responsiveness to TGF-beta-induced IL-1 counteraction. We investigated whether expression of TGF-beta and
its signaling molecules altered with age. To mimic the TGF-beta deprived conditions in aged mice, we assessed the functional
consequence of TGF-beta blocking. We isolated knee joints of mice aged 5 months or 2 years, half of which were exposed to
IL-1 by intra-articular injection 24 h prior to knee joint isolation. Immunohistochemistry was performed, staining for TGF-beta1,
-2 or -3, TGF-betaRI or -RII, Smad2, -3, -4, -6 and -7 and Smad-2P. The percentage of cells staining positive was determined
in tibial cartilage. To mimic the lack of TGF-beta signaling in old mice, young mice were injected with IL-1 and after 2 days
Ad-LAP (TGF-beta inhibitor) or a control virus were injected. Proteoglycan (PG) synthesis (35S-sulfate incorporation) and PG content of the cartilage were determined. Our experiments revealed that TGF-beta2 and -3 expression
decreased with age, as did the TGF-beta receptors. Although the number of cells positive for the Smad proteins was not altered,
the number of cells expressing Smad2P strongly dropped in old mice. IL-1 did not alter the expression patterns. We mimicked
the lack of TGF-beta signaling in old mice by TGF-beta inhibition with LAP. This resulted in a reduced level of PG synthesis
and aggravation of PG depletion. The limited response of old mice to TGF-beta induced-IL-1 counteraction is not due to a diminished
level of intracellular signaling molecules or an upregulation of intracellular inhibitors, but is likely due to an intrinsic
absence of sufficient TGF-beta receptor expression. Blocking TGF-beta distorted the natural repair response after IL-1 injection.
In conclusion, TGF-beta appears to play an important role in repair of cartilage and a lack of TGF-beta responsiveness in
old mice might be at the root of OA development. 相似文献
76.
Boucquey A Vilhardt F Mitrovic T Franco D Weber A Horellou P 《Biochemical and biophysical research communications》2005,331(4):1485-1493
Tumors frequently express urokinase (uPA) receptor (uPAR). To investigate whether uPAR can efficiently target cancerous cells using amphotropic retroviral vectors, we generated a retrovirus displaying the amino-terminal fragment (ATF) of uPA as an N-terminal extension of viral envelope protein. We also made use of a "two-step strategy" by inserting a uPA cleavage site between the ATF moiety and the envelope. We measured the ability of ATF-bearing chimeric envelopes to infect huPAR-overexpressing Madin-Darby canine kidney (MDCK) and control MDCK II cells. The ATF-viruses infected both MDCK cell lines with an equivalent efficiency, suggesting that the chimeric viruses were not sequestered by uPAR and infect cells preferentially via the Pit-2 receptor. The addition of a uPA cleavage site increased the infection level of huPAR-MDCK cells by 2-fold when uPA was present in the infection medium. Surprisingly, ATF-env viruses infected huPAR-MDCK cells 5.5-fold more efficiently in the presence of exogenous uPA. This stimulatory effect of uPA on infection of huPAR-MDCK cells by the ATF-env virus was completely abolished by methyl-beta-cyclodextrin, suggesting that this effect involves the caveolar endocytosis pathway. 相似文献
77.
Sommer F Drepper F Haehnel W Hippler M 《The Journal of biological chemistry》2004,279(19):20009-20017
On the lumenal side of photosystem I (PSI), each of the two large core subunits, PsaA and PsaB, expose a conserved tryptophan residue to the surface. PsaB-Trp(627) is part of the hydrophobic recognition site that is essential for tight binding of the two electron donors plastocyanin and cytochrome c(6) to the donor side of PSI (Sommer, F., Drepper, F., and Hippler, M. (2002) J. Biol. Chem. 277, 6573-6581). To examine the function of PsaA-Trp(651) in binding and electron transfer of both donors to PSI, we generated the mutants PsaA-W651F and PsaA-W651S by site-directed mutagenesis and biolistic transformation of Chlamydomonas reinhardtii. The protein-protein interaction and the electron transfer between the donors and PSI isolated from the mutants were analyzed by flash absorption spectroscopy. The mutation PsaA-W651F completely abolished the formation of a first order electron transfer complex between plastocyanin (pc) and the altered PSI and increased the dissociation constant for binding of cytochrome (cyt) c(6) by more than a factor of 10 as compared with wild type. Mutation of PsaA-Trp(651) to Ser had an even larger impact on the dissociation constant. The K(D) value increased another 2-fold when the values obtained for the interaction and electron transfer between cyt c(6) and PSI from PsaA-W651S and PsaA-W651F are compared. In contrast, binding and electron transfer of pc to PSI from PsaA-W651S improved as compared with PSI from PsaA-W651F and admitted the formation of an inter-molecular electron transfer complex, resulting in a K(D) value of about 554 microm that is still five times higher than observed for wild type. These results demonstrate that PsaA-Trp(651) is, such as PsaB-Trp(627), crucial for high affinity binding of pc and cyt c(6) to PSI. Our results also indicate that the highly conserved structural recognition motif that is formed by PsaA-Trp(651) and PsaB-Trp(627) confers a differential selectivity in binding of both donors to PSI. 相似文献
78.
This report describes a case series of septicaemia caused by infection with Aerococcus viridans in immunodeficient NOD/LtSz-Prkdc(scid) (NOD/SCID) mice. During a period of 3 weeks more than 40 animals died or became ill with clinical signs of ruffled coat, weight loss, laboured breeding, and distended abdomen. At necropsy it was found that the animals displayed symptoms of sepsis with widespread abscesses in the liver, heart, lungs or pyogenic peritonitis. A Gram-positive coccus was isolated in pure culture from the abscesses or peritoneum from affected animals. According to phenotypic and phylogenetic characterization, the isolate was identified as A. viridans. This is the first report of a spontaneous outbreak of septicaemia caused by A. viridans infection in immunodeficient laboratory mice and we conclude that A. viridans should be considered as a pathogen in immunodeficient mice. 相似文献
79.
Hutterer A Berdnik D Wirtz-Peitz F Zigman M Schleiffer A Knoblich JA 《Developmental cell》2006,11(2):147-157
The protein kinase Aurora-A is required for centrosome maturation, spindle assembly, and asymmetric protein localization during mitosis. Here, we describe the identification of Bora, a conserved protein that is required for the activation of Aurora-A at the onset of mitosis. In the Drosophila peripheral nervous system, bora mutants have defects during asymmetric cell division identical to those observed in aurora-A. Furthermore, overexpression of bora can rescue defects caused by mutations in aurora-A. Bora is conserved in vertebrates, and both Drosophila and human Bora can bind to Aurora-A and activate the kinase in vitro. In interphase cells, Bora is a nuclear protein, but upon entry into mitosis, Bora is excluded from the nucleus and translocates into the cytoplasm in a Cdc2-dependent manner. We propose a model in which activation of Cdc2 initiates the release of Bora into the cytoplasm where it can bind and activate Aurora-A. 相似文献
80.
Joke Hollants Frederik Leliaert Olivier De Clerck Anne Willems 《Symbiosis (Philadelphia, Pa.)》2010,51(1):131-138
In the search for endosymbiotic bacteria, elimination of ectosymbionts is a key point of attention. Commonly, the surface
of the host itself or the symbiotic structures are sterilized with aggressive substances such as chlorine or mercury derivatives.
Although these disinfectants are adequate to treat many species, they are not suitable for surface sterilization of delicate
samples. In order to study the bacterial endosymbionts in the marine green alga Bryopsis, the host plant’s cell wall was mechanically, chemically and enzymatically cleaned. Merely a chemical and enzymatic approach
proved to be highly effective. Bryopsis thalli treated with cetyltrimethylammonium bromide (CTAB) lysis buffer, proteinase K and bactericidal cleanser Umonium Master
showed no bacterial growth on agar plates or bacterial fluorescence when stained with a DNA fluorochrome. Moreover, the algal
cells were intact after sterilization, suggesting endophytic DNA is still present within these algae. This new surface sterilization
procedure opens the way to explore endosymbiotic microbial communities of other, even difficult to handle, samples. 相似文献