Experimental test of contextuality in quantum and classical systems

Contextuality is considered as an intrinsic signature of non-classicality, and a crucial resource for achieving unique advantages of quantum information processing. However, recently there have been debates on whether classical fields may also demonstrate contextuality. Here we experimentally configure a contextuality test for optical fields, adopting various definitions of measurement events, and analyse how the definitions affect the emergence of non-classical correlations. The heralded single photon state, a typical non-classical light field, manifests contextuality in our setup, while contextuality for classical coherent fields strongly depends on the specific definition of measurement events which is equivalent to filtering the non-classical component of the input state. Our results highlight the importance of definition of measurement events to demonstrate contextuality, and link the contextual correlations to non-classicality defined by quasi-probabilities in phase space.Comment: 17 pages, 7 figure

Distillation of Gaussian Einstein-Podolsky-Rosen steering with noiseless linear amplification

Einstein-Podolsky-Rosen (EPR) steering is one of the most intriguing features of quantum mechanics and an important resource for quantum communication. The inevitable loss and noise in the quantum channel will lead to decrease of the steerability and turn it from two-way to one-way. Despite an extensive research on protecting entanglement from decoherence, it remains a challenge to protect EPR steering due to its intrinsic difference from entanglement. Here, we experimentally demonstrate the distillation of Gaussian EPR steering in lossy and noisy environment using measurement-based noiseless linear amplification. Our scheme recovers the two-way steerability from one-way in certain region of loss and enhances EPR steering for both directions. We also show that the distilled EPR steering allows to extract secret key in one-sided device-independent quantum key distribution. Our work paves the way for quantum communication exploiting EPR steering in practical quantum channels

Direct Conversion of Mouse Fibroblasts into Cholangiocyte Progenitor Cells

Disorders of the biliary epithelium, known as cholangiopathies, cause severe and irreversible liver diseases. The limited accessibility of bile duct precludes modeling of several cholangiocyte-mediated diseases. Therefore, novel approaches for obtaining functional cholangiocytes with high purity are needed. Previous work has shown that the combination of Hnf1β and Foxa3 could directly convert mouse fibroblasts into bipotential hepatic stem cell-like cells, termed iHepSCs. However, the efficiency of converting fibroblasts into iHepSCs is low, and these iHepSCs exhibit extremely low differentiation potential into cholangiocytes, thus hindering the translation of iHepSCs to the clinic. Here, we describe that the expression of Hnf1α and Foxa3 dramatically facilitates the robust generation of iHepSCs. Notably, prolonged in vitro culture of Hnf1α- and Foxa3-derived iHepSCs induces a Notch signaling-mediated secondary conversion into cholangiocyte progenitor-like cells that display dramatically enhanced differentiation capacity into mature cholangiocytes. Our study provides a robust two-step approach for obtaining cholangiocyte progenitor-like cells using defined factors

Longitudinal [18F]FDG and [13N]NH3 PET/CT imaging of brain and spinal cord in a canine hemisection spinal cord injury model

To further understand the neurological changes induced by spinal cord injury (SCI) in its acute and subacute stages, we evaluated longitudinal changes in glucose and glutamate metabolism in the spinal cord and brain regions of a canine hemisection SCI model. [18F]FDG and [13N]NH3 positron-emission tomography (PET) with computed tomography (CT) was performed before SCI and at 1, 3, 7, 14, and 21 days after SCI. Spinal cord [18F]FDG uptake increased and peaked at 3 days post SCI. Similar changes were observed in the brain regions but were not statistically significant. Compared to the acute phase of SCI, [13N]NH3 uptake increased in the subacute stage and peaked at 7 days post SCI in all analyzed brain regions. But in spinal cord, no [13N]NH3 uptake was detected before SCI when the blood-spinal cord barrier (BSCB) was intact, then gradually increased when the BSCB was damaged after SCI. [13N]NH3 uptake was significantly correlated with plasma levels of the BSCB disruption marker, monocyte chemoattractant protein-1 (MCP-1). Overall, we showed that SCI induced in vivo changes in glucose uptake in both the spinal cord and the examined brain regions, and changes in glutamine synthetase activity in the latter. Moreover, our results suggest that [13N]NH3 PET may serve as a potential method for assessing BSCB permeability in vivo.</div

Homozygous mutation in DNAAF4 causes primary ciliary dyskinesia in a Chinese family

Primary ciliary dyskinesia (PCD) is a rare autosomal recessive disorder that affects the structure and function of motile cilia, leading to classic clinical phenotypes, such as situs inversus, chronic sinusitis, bronchiectasis, repeated pneumonia and infertility. In this study, we diagnosed a female patient with PCD who was born in a consanguineous family through classic clinical manifestations, transmission electron microscopy and immunofluorescence staining. A novel DNAAF4 variant NM_130810: c.1118G&gt;A (p. G373E) was filtered through Whole-exome sequencing. Subsequently, we explored the effect of the mutation on DNAAF4 protein from three aspects: protein expression, stability and interaction with downstream DNAAF2 protein through a series of experiments, such as transfection of plasmids and Co-immunoprecipitation. Finally, we confirmed that the mutation of DNAAF4 lead to PCD by reducing the stability of DNAAF4 protein, but the expression and function of DNAAF4 protein were not affected

Intravenous transplantation of olfactory ensheathing cells reduces neuroinflammation after spinal cord injury via interleukin-1 receptor antagonist

Rationale: Olfactory ensheathing cell (OEC) transplantation has emerged as a promising therapy for spinal cord injury (SCI) repair. In the present study, we explored the possible mechanisms of OECs transplantation underlying neuroinflammation modulation.Methods: Spinal cord inflammation after intravenous OEC transplantation was detected in vivo and ex vivo by translocator protein PET tracer [F-18]F-DPA. To track transplanted cells, OECs were transduced with enhanced green fluorescent protein (eGFP) and HSV1-39tk using lentiviral vector and were monitored by fluorescence imaging and [F-18]FHBG study. Protein microarray analysis and ELISA studies were employed to analyze differential proteins in the injured spinal cord after OEC transplantation. The anti-inflammation function of the upregulated protein was also proved by in vitro gene knocking down experiments and OECs/microglia co-culture experiment.Results: The inflammation in the spinal cord was decreased after OEC intravenous transplantation. The HSV1-39tk-eGFP-transduced OECs showed no accumulation in major organs and were found at the injury site. After OEC transplantation, in the spinal cord tissues, the interleukin-1 receptor antagonist (IL-1Ra) was highly upregulated while many chemokines, including pro-inflammatory chemokines IL-1 alpha, IL-1 beta were downregulated. In vitro studies confirmed that lipopolysaccharide (LPS) stimulus triggered OECs to secrete IL-1Ra. OECs significantly suppressed LPS-stimulated microglial activity, whereas IL-1Ra gene knockdown significantly reduced their ability to modulate microglial activity.Conclusion: The OECs that reached the lesion site were activated by the release of pro-inflammatory cytokines from activated microglia in the lesion site and secreted IL-1Ra to reduce neuroinflammation. Intravenous transplantation of OECs has high therapeutic effectiveness for the treatment of SCI via the secretion of IL-1Ra to reduce neuroinflammation

CoNIC Challenge: Pushing the Frontiers of Nuclear Detection, Segmentation, Classification and Counting

Nuclear detection, segmentation and morphometric profiling are essential in helping us further understand the relationship between histology and patient outcome. To drive innovation in this area, we setup a community-wide challenge using the largest available dataset of its kind to assess nuclear segmentation and cellular composition. Our challenge, named CoNIC, stimulated the development of reproducible algorithms for cellular recognition with real-time result inspection on public leaderboards. We conducted an extensive post-challenge analysis based on the top-performing models using 1,658 whole-slide images of colon tissue. With around 700 million detected nuclei per model, associated features were used for dysplasia grading and survival analysis, where we demonstrated that the challenge's improvement over the previous state-of-the-art led to significant boosts in downstream performance. Our findings also suggest that eosinophils and neutrophils play an important role in the tumour microevironment. We release challenge models and WSI-level results to foster the development of further methods for biomarker discovery