Exuberant de novo dendritic spine growth in mature neurons

Dendritic spines are structural correlates of excitatory synapses maintaining stable synaptic communications. However, this strong spine-synapse relationship was mainly characterized in excitatory pyramidal neurons (PyNs), raising a possibility that inferring synaptic density from dendritic spine number may not be universally applied to all neuronal types. Here we found that the ectopic expression of H-Ras increased dendritic protrusion numbers regardless of cortical cell types such as layer 2/3 pyramidal neurons (PyNs), parvalbumin (PV)- and vasoactive intestinal peptide (VIP)-positive interneurons (INs) in the primary motor cortex (M1). The probability of detecting dendritic protrusions, including spines, was positively correlated with the magnitude of H-Ras activity, suggesting elevated local H-Ras activity is involved in the process of dendritic spine formation. H-Ras overexpression caused a high spine turnover rate via adding more protrusions rather than eliminating them. Two-photon photolysis of glutamate triggered de novo dendritic spine formation in mature neurons, suggesting H-Ras-induced spine formation is not restricted to early development. In PyNs and PV-INs, but not VIP-INs, we observed a shift in average spine neck length towards longer filopodia-like phenotypes. The portion of dendritic protrusions lacking key excitatory synaptic proteins was significantly increased in H-Ras transfected neurons, suggesting that these increased protrusions, including spines, may not be functional. Consistent with this, high protrusion density caused by H-Ras did not result in a change in the frequency or the amplitude of miniature excitatory postsynaptic currents (mEPSCs). Thus, our results propose that dendritic protrusions, including spines, possess more multifaceted functions beyond the morphological proxy of the excitatory synapse

Characterizing Depth of Defects with Low Size/Depth Aspect Ratio and Low Thermal Reflection by Using Pulsed IR Thermography

This study is focused on the quantitative estimation of defect depth by applying pulsed thermal nondestructive testing. The majority of known defect characterization techniques are based on 1D heat conduction solutions, thus being inappropriate for evaluating defects with low aspect ratios. A novel method for estimating defect depth is proposed by taking into account the phenomenon of 3D heat diffusion, finite lateral size of defects and the thermal reflection coefficient at the boundary between a host material and defects. The method is based on the combination of a known analytical model and a non-linear fitting (NLF) procedure. The algorithm was verified both numerically and experimentally on 3D-printed polylactic acid plastic samples. The accuracy of depth prediction using the proposed method was compared with the reference characterization technique based on thermographic signal reconstruction to demonstrate the efficiency of the proposed NLF method

Decidualization and syndecan-1 knock down sensitize endometrial stromal cells to apoptosis induced by embryonic stimuli.

Human embryo invasion and implantation into the inner wall of the maternal uterus, the endometrium, is the pivotal process for a successful pregnancy. Whereas disruption of the endometrial epithelial layer was already correlated with the programmed cell death, the role of apoptosis of the subjacent endometrial stromal cells during implantation is indistinct. The aim was to clarify whether apoptosis plays a role in the stromal invasion and to characterize if the apoptotic susceptibility of endometrial stromal cells to embryonic stimuli is influenced by decidualization and Syndecan-1. Therefore, the immortalized human endometrial stromal cell line St-T1 was used to first generate a new cell line with a stable Syndecan-1 knock down (KdS1), and second to further decidualize the cells with progesterone. As a replacement for the ethically inapplicable embryo all cells were treated with the embryonic factors and secretion products interleukin-1β, interferon-γ, tumor necrosis factor-α, transforming growth factor-β1 and anti-Fas antibody to mimic the embryo contact. Detection of apoptosis was verified via Caspase ELISAs, PARP cleavage and Annexin V staining. Apoptosis-related proteins were investigated via antibody arrays and underlying signaling pathways were analyzed by Western blot. Non-decidualized endometrial stromal cells showed a resistance towards apoptosis which was rescinded by decidualization and Syndecan-1 knock down independent of decidualization. This was correlated with an altered expression of several pro- and anti-apoptotic proteins and connected to a higher activation of pro-survival Akt in non-differentiated St-T1 as an upstream mediator of apoptotis-related proteins. This study provides insight into the largely elusive process of implantation, proposing an important role for stromal cell apoptosis to successfully establish a pregnancy. The impact of Syndecan-1 in attenuating the apoptotic signal is particularly interesting in the light of an already described influence on pregnancy disorders and therefore might provide a useful clinical tool in the future to prevent pregnancy complications provoked by inadequate implantation

Can TSH level and premenstrual spotting constitute a non-invasive marker for the diagnosis of endometriosis?

Background!#!To date, there is no reliable non-invasive marker for the early detection and diagnosis of endometriosis available possibly resulting in a delayed diagnosis and consequently an unnecessary long ordeal for the individual woman. Therefore, the primary objective of the current study was to evaluate whether the combination of a thyroid-stimulating hormone (TSH) level > 2.5 µlU/ml and premenstrual spotting could serve as non-invasive markers of endometriosis. A secondary objective was to determine whether typical symptoms of endometriosis like dysmenorrhea and/or dyspareunia could increase the diagnostic reliability.!##!Methods!#!We conducted a retrospective, case-control study with 167 female patients at the Department of OB/GYN and REI (UniKiD) of the medical center of the University of Düsseldorf, between January 2015 and December 2016. 107 women with surgically confirmed endometriosis were compared to 60 without endometriosis (controls). To evaluate the diagnostic accuracy, we considered sensitivity, specificity and predictive values. In order to assess the association between the non-invasive markers and endometriosis an odds ratio (OR) with a 95% confidence interval was calculated.!##!Results!#!In our cohort, diagnosis of endometriosis with non-invasive markers according to their sensitivity yielded the following ranking: increased TSH level, premenstrual spotting, combination of both previous parameters, addition of dysmenorrhea, addition of dyspareunia and combination of all parameters.!##!Conclusion!#!The existence of endometriosis should be taken into consideration when a patient suffers from thyroid dysfunction and premenstrual spotting. Apart from an increased TSH level, the presence of premenstrual spotting underlines the possible diagnosis of endometriosis with non-invasive markers and therefore, the patient´s history needs to be taken into account carefully. Trial registration The retrospective study was approved by the Ethics Committee of the medical faculty of the Heinrich-Heine University, Düsseldorf, Germany, Registration number Düsseldorf: 5371R (approved: April 04th, 2016). Since the design of the study was retrospective no written informed consent was necessary

Serum anti-Müllerian hormone concentration and follicle density throughout reproductive life and in different diseases-implications in fertility preservation.

STUDY QUESTION How do anti-Müllerian hormone (AMH) serum concentrations and follicle densities (FDs) change with age and disease and what are the implications for fertility preservation? SUMMARY ANSWER AMH concentrations and FD do not correlate in young women, and AMH but not FD is reduced in some diseases, limiting the value of AMH as a predictive parameter of ovarian tissue transplantation. WHAT IS KNOWN ALREADY AMH is widely used as a parameter to estimate the ovarian reserve. However, the reliability of AMH to predict total number of follicles and the FD is questionable. Women with lymphoma and leukaemia have been shown to have reduced AMH concentrations, but it is unknown if the FD is also reduced. In fertility preservation it is essential to estimate the correct total number of follicles and the FD, as ovarian tissue should only be cryopreserved if ovarian reserve is high. Furthermore, the amount of tissue to be transplanted should be based on the estimation of the real FD. STUDY DESIGN, SIZE, DURATION This retrospective observational study included 830 women (mean ± SD age, 28.2 ± 6.81 years; range, 4-43 years) with malignant (n = 806) and benign (n = 24) diseases who cryopreserved tissue in a single centre as part of a national fertility preservation programme. Females with ovarian surgery or known predispositions for a reduced ovarian reserve were excluded. AMH concentrations and FD were evaluated from March 2011 to September 2016. PARTICIPANTS/MATERIALS, SETTING, METHODS AMH concentrations were analysed before gonadotoxic therapies. Standardized biopsies, obtained from different areas of ovarian cortex, were collected. FD was analysed after tissue digestion and calcein staining and was expressed as average number of primordial and primary follicles count per 3 mm biopsy and per cubic millimeter tissue. AMH concentrations and FD were analysed in relation to age and diagnosis group. Both parameters were age adjusted, and associations between the different diagnosis groups and AMH versus FD were assessed. MAIN RESULTS AND THE ROLE OF CHANCE Mean ± SD AMH concentration was 3.1 ± 2.81 g/ml, mean FD per 3 mm biopsy was 137 ± 173.9 and 19.4 ± 24.60 per mm3. Maximum AMH concentrations were found in children and teenagers at the age of 6-10 years (5.71 ng/ml) and in adults at the age of 21-25 years (3.33 ng/ml). FD was highest in young children up to an age of 15 years and decreased with increasing age. AMH and FD were not correlated in women ≤20 years and weakly to moderately correlated in women 21-40 years (r = 0.24-0.39). Age-adjusted correlations between AMH and FD were demonstrated in several diagnosis groups such as breast cancer, leukaemia, sarcoma, gastrointestinal cancer and gynaecological cancer but not in the groups exhibiting Hodgkin's and non-Hodgkin's lymphoma, cerebral cancer, other types of malignancies and other types of benign diseases. Further statistical analysis supported the finding that, in some diagnosis groups such as Hodgkin's lymphoma and in gynaecological cancer, AMH concentrations but not FDs are reduced, questioning the prognostic accuracy of AMH for the FD in these diseases. LIMITATIONS, REASONS FOR CAUTION Even though biopsies were taken from different sites, heterogenous distribution of follicles might have had some effect on the accuracy of the analysis. WIDER IMPLICATION OF THE FINDINGS AMH should be used with care to estimate the total ovarian reserve and FD of cancer patients in young women in some diseases. Therefore, calculating the amount of ovarian tissue to be transplanted based solely on AMH might be inaccurate whereas FD might be a better parameter. STUDY FUNDING/COMPETING INTEREST(S) The study did not receive any exterior funding