20 research outputs found

    Alterations of T cell activation signalling and cytokine production by postmenopausal estrogen levels

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    <p>Abstract</p> <p>Background</p> <p>Immunosenescence is an age-associated disorder occurring primarily in T cell compartments, including altered subset composition, functions, and activation. In women, evidence implicates diminished estrogen in the postmenopausal period as a contributing factor to diminished T cell responsiveness. Since hypoestrogenism is present in postmenopausal women, our objective focused on whether T cell activation, defined as signalling molecule expressions and activation, and function, identified as IL-2 production, were affected by low estrogen.</p> <p>Methods</p> <p>Using Jurkat 6.1 T cells, consequences of 4 pg/ml (corresponding to postmenopausal levels) or 40 pg/ml (premenopausal levels) of estradiol (E<sub>2</sub>) were analyzed on signalling proteins, CD3-zeta, JAK2, and JAK3, determined by Western immunoblotting. These consequences were correlated with corresponding gene expressions, quantified by real time-polymerase chain reaction. Tyrosine phosphorylation of CD3-zeta was defined by immunoprecipitation and western immunoblotting following activation by T cell receptor (TcR) cross-linking. CD3-zeta expression and modulation was also confirmed in T cells from pre- and postmenopausal women. To assess functional consequences, IL-2 production, induced by PMA and ionomycin, was determined using enzyme-linked immunosorbent spot assay (ELISpot).</p> <p>Results</p> <p>At 40 pg/ml E<sub>2</sub>, the level of signalling protein CD3-zeta was elevated 1.57-fold, compared with cells exposed to 4 pg/ml E<sub>2</sub>. The CD3-zeta proteins also exhibited altered levels of activation-induced phosphorylation in the presence of 40 pg/ml E<sub>2 </sub>versus 4 pg/ml: 23 kD phosphorylated form increased 2.64-fold and the 21 kD form was elevated 2.95-fold. Examination of kinases associated with activation signalling also demonstrated that, in the presence of 40 pg/ml E<sub>2</sub>, JAK2 protein expression was increased 1.64-fold (p < 0.001) and JAK3 enhanced 1.79-fold (p < 0.001) compared to 4 pg/ml. mRNA levels for CD3-zeta, JAK2, and JAK3 were significantly increased following exposure to 40 pg/ml E<sub>2 </sub>(2.39, 2.01, and 2.21 fold, respectively) versus 4 pg/ml. These findings were confirmed in vivo, since T cells from postmenopausal women exhibited 7.2-fold diminished CD3-zeta expression, compared to pre-menopausal controls and this expression was elevated 3.8-fold by addition of 40 pg/ml E<sub>2</sub>. Functionally, Jurkat cells exposed to 40 pg/ml E<sub>2 </sub>and activated exhibited significantly elevated numbers of IL-2 producing colonies compared to 4 pg/ml (75.3 ± 2.2 versus 55.7 ± 2.1 colonies, p < 0.0001).</p> <p>Conclusion</p> <p>Jurkat T cells exposed to 4 pg/ml E<sub>2 </sub>expressed significantly diminished activation signalling proteins, correlating with reduced IL-2 production. Lower signalling protein levels appear to result from decreased CD3-zeta, JAK2, and JAK3 gene expressions. These findings may provide a molecular basis for immunosenescence associated with the postmenopausal state.</p

    Maternal serum concentration of anti-MĂĽllerian hormone is a better predictor than basal follicle stimulating hormone of successful blastocysts development during IVF treatment.

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    BackgroundThe conditions of diminished ovarian reserve and primary ovarian insufficiency, characterized by poor fertility outcomes, currently comprise a major challenge in reproductive medicine, particularly in vitro fertilization. Currently in the IVF industry, blastocyst developmental success rate per treatment is routinely overlooked when a live birth results from treatment. Limited data are available on this significant and actionable variable of blastocyst development optimization, which contributes to improvement of treatment success Women with elevated basal FSH concentration are reported to still achieve reasonable pregnancy rates, although only a few studies report correlations with blastocysts development. Diagnostic values of AMH/basal FSH concentrations can be useful for determining the optimal stimulation protocol as well as identification of individuals who will not benefit from IVF due to poor prognosis. The objective of this study is to identify actionable clinical and culture characteristics of IVF treatment that influence blastocyst developmental rate, with the goal of acquiring optimal success.Methods and findingsA retrospective observational study was performed, based on 106 women undergoing IVF, regardless of prognosis, over a six-month period from January 1, 2015 to June 31, 2015. Rate of high-quality blastocyst production, which can be used for embryo transfer or vitrification, per normally fertilized oocyte, was evaluated. Treatment was determined successful when outcome was ≥ 40% high-quality blastocysts. The data were initially evaluated with the Evtree algorithm, a statistical computational analysis which is inspired by natural Darwinian evolution incorporating concepts such as mutation and natural selection (see Supplementary Material). The analysis processes all variables simultaneously against the outcome, aiming to maximize discrimination of each variable to then create a "branch" of the tree which can be used as a decision in treatment. The final model results in only those variables which are significant to outcomes. Generalized linear model (GLM) employing logistic regression and survival analysis with R software was used and the final fitting of the model was determined through the use of random forest and evolutionary tree algorithms. Individuals presenting with an [AMH] of >3.15 ng/ml and a good prognosis had a lower success per treatment (n = 11, 0% success) when total gonadotropin doses were greater than 3325 IU. Individuals that presented with an [AMH] of Conclusions[AMH] is a superior indicator of ovarian stimulation response and an actionable variable for stimulation dose management for optimizing blastocyst development in culture. Women whose [AMH] is ≥3.2 mg/ml, having a good prognosis, and developing >12 mature follicles result in <40% blastocysts when gonadotropin doses exceed 3325 IU per treatment. IVF treatments for poor responders that present with infertility due to diminished ovarian reserve, if managed appropriately, can produce more usable blastocyst per IVF treatment, thus increasing rate of blastocyst developmental success and ultimately increasing live birth rates. Future studies are needed to investigate the intra-follicular and the intra-cellular mechanisms that lead to the inverse relationship of blastocysts development and total gonadotropin doses in good responders in contrast to poor responders

    micromachines Holographic Fabrication of Designed Functional Defect Lines in Photonic Crystal Lattice Using a Spatial Light Modulator

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    Abstract: We report the holographic fabrication of designed defect lines in photonic crystal lattices through phase engineering using a spatial light modulator (SLM). The diffracted beams from the SLM not only carry the defect&apos;s content but also the defect related phase-shifting information. The phase-shifting induced lattice shifting in photonic lattices around the defects in three-beam interference is less than the one produced by five-beam interference due to the alternating shifting in lattice in three beam interference. By designing the defect line at a 45 degree orientation and using three-beam interference, the defect orientation can be aligned with the background photonic lattice, and the shifting is only in one side of the defect line, in agreement with the theory. Finally, a new design for the integration of functional defect lines in a background phase pattern reduces the relative phase shift of the defect and utilizes the different diffraction efficiency between the defect line and background phase pattern. We demonstrate that the desired and functional defect lattice can be registered into the background lattice through the direct imaging of designed phase patterns

    Maternal Obesity Induces Epigenetic Modifications to Facilitate Zfp423 Expression and Enhance Adipogenic Differentiation in Fetal Mice

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    Maternal obesity (MO) predisposes offspring to obesity and type 2 diabetes despite poorly defined mechanisms. Zfp423 is the key transcription factor committing cells to the adipogenic lineage, with exceptionally dense CpG sites in its promoter. We hypothesized that MO enhances adipogenic differentiation during fetal development through inducing epigenetic changes in the Zfp423 promoter and elevating its expression. Female mice were subjected to a control (Con) or obesogenic (OB) diet for 2 months, mated, and maintained on their diets during pregnancy. Fetal tissue was harvested at embryonic day 14.5 (E14.5), when the early adipogenic commitment is initiated. The Zfp423 expression was 3.6-fold higher and DNA methylation in the Zfp423 promoter was lower in OB compared with Con. Correspondingly, repressive histone methylation (H3K27me3) was lower in the Zfp423 promoter of OB fetal tissue, accompanied by reduced binding of enhancer of zeste 2 (EZH2). Gain- and loss-of-function analysis showed that Zfp423 regulates early adipogenic differentiation in fetal progenitor cells. In summary, MO enhanced Zfp423 expression and adipogenic differentiation during fetal development, at least partially through reducing DNA methylation in the Zfp423 promoter, which is expected to durably elevate adipogenic differentiation of progenitor cells in adult tissue, programming adiposity and metabolic dysfunction later in life
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