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The inverted coaxial point contact high purity germanium (ICPC HPGe) detector exhibits the advantages of large volume, low depletion voltage, small capacitance, and excellent pulse shape discrimination (PSD) capability. An ICPC detector prototype with 0.9 pF capacitance was successfully fabricated and tested in this study using two different front-end electronics. The detector weighted approximately 1.5 kg and the depletion voltage was only 1800 V. The optimized operating voltage was found to be 2500 V and the leakage current was 7 pA. The detector was first connected to a homemade JFET based front-end with a pulsed reset design to minimize parallel noise. An energy resolution of 1.72 keV (full width at half maximum) was achieved at 1332 keV, demonstrating the good charge collection efficiency of the detector. An RC feedback front-end circuit was employed to test the PSD properties using a 228Th source. The PSD capability is similar to that of typical broad energy or point contact HPGe detectors, but is notably improved when the charge trapping is corrected using the drift time. [ABSTRACT FROM AUTHOR]

What is the effect of micro-RNA (miR)-21-5p-loaded bone marrow mesenchymal stem cell-derived exosomes (miR-21-Exo) on autoimmune premature ovarian insufficiency (POI)? The Cell Counting Kit 8 (CCK8) assay, fluorescence-activated cell sorting, western blotting, quantitative reverse transcriptase (qRT)-PCR and enzyme-linked immunosorbent assay (ELISA) verified the effect of miR-21-Exo on interferon-γ (IFN-γ)-induced KGN cells. qRT-PCR, western blotting and dual-luciferase reporter gene assays verified that miR-21-Exo mediated Msh homeobox 1 (MSX1) regulation of the Notch signalling pathway and that miR-21 interacted directly with MSX1. The effects of miR-21-Exo on the ovaries were verified by monitoring of the oestrous cycle, haematoxylin and eosin staining, follicle counts, ELISA, immunohistochemistry, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL), western blotting and qRT-PCR. The results showed that miR-21-Exo promoted IFN-γ-induced KGN cell proliferation and hormone synthesis, and inhibited apoptosis. Using dual-luciferase reporter gene assays, miR-21 and MSX1 were shown to have direct interactions. Moreover, the findings elucidated that miR-21-Exo inhibited cell apoptosis and promoted hormone synthesis by mediating MSX1 to regulate the Notch signalling pathway. miR-21-Exo restored the ovarian structure in a mouse model of autoimmune POI, promoted endocrine function and proliferation, and inhibited apoptosis and inflammation in vivo. This study demonstrates that miR-21-Exo regulates the MSX1-mediated Notch signalling pathway to inhibit granulosa cell apoptosis and improve hormone synthesis function, providing insight into a potential mechanism of molecular therapy for the treatment of autoimmune POI. [Display omitted] [ABSTRACT FROM AUTHOR]

trans -Resveratrol, a natural polyphenol enriched in grape seed and skin, has been extensively investigated for its antioxidant, anti-inflammatory and anti-psychiatric properties. The present study examined the effects of trans -resveratrol on ameliorating anxiety-like behaviors and fear memory deficits induced by time-dependent sensitization (TDS) procedure, which is a classical animal model for mimicking posttraumatic stress disorder (PTSD). The results suggested that trans -resveratrol at doses of 10, 20 and 40 mg/kg (via gavage, i.g.) reversed TDS-induced decreases in the percentage of time spent in the center of arena, the open arm entries and time spent in the open arms in the open field and elevated plus maze tests. It also decreased the percentage of freezing time in the contextual fear paradigm that was increased in TDS treated rats. Further study suggested that TDS-induced abnormality in the limbic hypothalamus-pituitary-adrenal gland (L-HPA) axis was reversed by trans -resveratrol, i.e. it reversed increased adrenal gland index and corticotropin-releasing factor (CRF) levels, and rescued the differential expression of glucocorticoid receptor (GR) in the hypothalamus, hippocampus and amygdala. Neurobiological studies suggested that trans -resveratrol increased phosphorylation of cAMP response element binding protein (pCREB) and brain derived neurotrophic factor (BDNF) levels, which were decreased in rats subjected to TDS. These results provide compelling evidence that trans- resveratrol protects neurons against PTSD-like stress insults by regulation of L-HPA axis function and activation of downstream neuroprotective molecules, such as pCREB and BDNF expression. [ABSTRACT FROM AUTHOR]