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Tomic D Frech MS Babus JK Symonds D Furth PA Koos RD Flaws JA 《Reproductive toxicology (Elmsford, N.Y.)》2007,23(3):317-325
Recently, we generated transgenic mice in which ERalpha can be inducibly overexpressed in reproductive tissues (ERalpha overexpressors). These mice were used to test the hypothesis that prenatal and postnatal ERalpha overexpression reduces female fertility. To do so, litter sizes, ovulation, follicle numbers, uterine histology, implantation sites, and hormone levels were compared in ERalpha overexpressors and controls. The data indicate that ERalpha overexpressors have reduced fertility compared to controls and that the reduced fertility is not due to reduced ovulatory capacity, altered levels of estradiol, FSH, and LH, or impaired follicular growth. ERalpha overexpressors, however, had a higher number of apoptotic cells in the endometrial epithelium and a reduced number of implantation sites compared to controls. Thus, the increased number of apoptotic cells and reduced number of implantation sites observed in ERalpha overexpressing uteri compared to controls may, in part, account for the reduced litter size produced by ERalpha overexpressing females. 相似文献
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SJ Mundell A-L Matharu S Nisar TM Palmer JL Benovic E Kelly 《British journal of pharmacology》2010,159(3):518-533
Background and purpose:
We have investigated the effect of deletions of a postsynaptic density, disc large and zo-1 protein (PDZ) motif at the end of the COOH-terminus of the rat A2B adenosine receptor on intracellular trafficking following long-term exposure to the agonist 5′-(N-ethylcarboxamido)-adenosine.Experimental approach:
The trafficking of the wild type A2B adenosine receptor and deletion mutants expressed in Chinese hamster ovary cells was studied using an enzyme-linked immunosorbent assay in combination with immunofluorescence microscopy.Key results:
The wild type A2B adenosine receptor and deletion mutants were all extensively internalized following prolonged treatment with NECA. The intracellular compartment through which the Gln325-stop receptor mutant, which lacks the Type II PDZ motif found in the wild type receptor initially trafficked was not the same as the wild type receptor. Expression of dominant negative mutants of arrestin-2, dynamin or Eps-15 inhibited internalization of wild type and Leu330-stop receptors, whereas only dominant negative mutant dynamin inhibited agonist-induced internalization of Gln325-stop, Ser326-stop and Phe328-stop receptors. Following internalization, the wild type A2B adenosine receptor recycled rapidly to the cell surface, whereas the Gln325-stop receptor did not recycle.Conclusions and implications:
Deletion of the COOH-terminus of the A2B adenosine receptor beyond Leu330 switches internalization from an arrestin- and clathrin-dependent pathway to one that is dynamin dependent but arrestin and clathrin independent. The presence of a Type II PDZ motif appears to be essential for arrestin- and clathrin-dependent internalization, as well as recycling of the A2B adenosine receptor following prolonged agonist addition. 相似文献117.
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Justin van Loon Daniël Hoornenborg Harm M van der Vis Inger N Sierevelt Kim TM Opdam Gino MMJ Kerkhoffs Daniël Haverkamp 《World journal of orthopedics》2021,12(1):14
BACKGROUNDIn press-fit total hip arthroplasty (THA) ceramic-on-ceramic (CoC) bearings are a potential for overcoming the wear that is seen in ceramic-on-polyethylene (CoPE) bearings, and can lead to wear-induced osteolysis, resulting in loosening of the implant. However, CoC bearings show disadvantages as well, such as squeaking sounds and being more fragile, which can cause ceramic head or liner fracture. Because comparative long-term studies are limited, the objective of this study was to determine the long-term difference in wear, identify potential predictive factors for wear, investigate radiological findings such as osteolysis, and evaluate clinical functioning and complications between these bearings.AIMTo determine 10-year differences in wear, predictive factors for wear, and investigate radiological findings and clinical functioning between CoC and CoPE.METHODSThis observational prospective single-center cohort study with a 10-year follow-up includes a documented series of elective THAs. Primary outcome was wear measured by anteroposterior (AP) radiographs. Secondary outcomes were potential predictive factors for wear, complications during follow-up, Harris hip score (HHS), and radiological findings such as presence of radiolucency, osteolysis, atrophy, and hypertrophy around the cup. Due to the absence of wear in the CoC group, stratified analysis to identify risk factors for wear was only performed in the CoPE group by use of univariate linear regression analysis. HHS was expressed as a change from baseline and the association with bearing type was assessed by use of multivariate linear regression analysis, adjusted for potential confounders.RESULTSA total of 17 CoPE (63.0%) and 25 CoC (73.5%) cases were available for follow-up and showed a linear wear of respectively 0.130 mm/year (range 0.010; 0.350) and 0.000 mm/year (range 0.000; 0.005), which was significant (P < 0.001) between both groups. Wear always occurred in the cranial direction. Cup inclination was the only predictive factor for polyethylene (PE) wear. No dislocations, ceramic head, or liner fractures were seen. The HHS showed a mean change from baseline of 37.1 points (SD 18.5) in the CoPE group and 43.9 (SD 17.0) in the CoC group. This crude difference of 6.8 (range -5.2; 18.7) in favor of the CoC group was not significant (P = 0.26) and was not significant when adjusted for age, gender, and diagnosis either (P = 0.99). No significant differences in complications and radiological findings were seen between groups. CONCLUSIONCoC bearing shows lower wear rates compared to CoPE at 10-year follow-up with cup inclination as a predictive factor for wear and no differences in complications, HHS, and radiological findings. 相似文献
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Yan X Lukas J Witt M Wree A Hübner R Frech M Köhling R Rolfs A Luo J 《Metabolic brain disease》2011,26(4):299-306
Niemann-Pick type C 1 (NPC1) disease is an autosomal recessive cholesterol transport defect resulting in a neurodegenerative
process in patients mainly at an early age, although some patients may start with manifestation in adult. Since loss of myelin
is considered as a main pathogenetic factor, the precise mechanism inducing dysmylination in NPC1 disease is still unclear.
In the present study, a quantitative evaluation on the myelin protein and its regulatory factors of oligodendrocytes, such
as SRY-related HMG-box 10 (Sox10), Yin Yang 1 factor (YY1) and myelin gene regulatory factor (MRF), in different parts of
the brain and spinal cord was performed in NPC1-mutant mice. The results showed that NPC1 protein was expressed in oligodendrocytes
and the amount of myelin protein was generally decreased in all parts of the brain and spinal cord in NPC1-mutant mice. Compared
to wild type, the amount of Sox10 and YY1 was not different in NPC1-mutant mice, but MRF was significantly decreased, suggesting
a possible mechanism perturbing differentiation of oligodendrocytes and the myelination process in the NPC1-mutant mouse. 相似文献
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