Towards a genereric 3D urban information meta-model

peer reviewedThe need of 3D urban spatial data infrastructures (3D SDI) is now almost commonly accepted. However, their implementation suffers from a lack of standardisation. This is usually due to an underestimation of the initial conceptual step, where modelling options should be clearly stated. In this article, we present a modelling ontological approach inspired by our experience in spatial data acquisition techniques. In this ontology, one considers that the universe is composed of free space and occupied space and that their interface is the only measurable feature. On that basis, we present a generic 3D urban spatial information meta-model. This meta-model is compared to the City GML standard through the study of the building object. Expect from some level-ofdetail issues, both models are compatible

Organotypic Spinal Cord Slice Culture to Study Neural Stem/Progenitor Cell Microenvironment in the Injured Spinal Cord

The molecular microenvironment of the injured spinal cord does not support survival and differentiation of either grafted or endogenous NSCs, restricting the effectiveness of the NSC-based cell replacement strategy. Studying the biology of NSCs in in vivo usually requires a considerable amount of time and cost, and the complexity of the in vivo system makes it difficult to identify individual environmental factors. The present study sought to establish the organotypic spinal cord slice culture that closely mimics the in vivo environment. The cultured spinal cord slices preserved the cytoarchitecture consisting of neurons in the gray matter and interspersed glial cells. The majority of focally applied exogenous NSCs survived up to 4 weeks. Pre-exposure of the cultured slices to a hypoxic chamber markedly reduced the survival of seeded NSCs on the slices. Differentiation into mature neurons was severely limited in this co-culture system. Endogenous neural progenitor cells were marked by BrdU incorporation, and applying an inflammatory cytokine IL-1β significantly increased the extent of endogenous neural progenitors with the oligodendrocytic lineage. The present study shows that the organotypic spinal cord slice culture can be properly utilized to study molecular factors from the post-injury microenvironment affecting NSCs in the injured spinal cord

Alpha-Synuclein Cell-to-Cell Transfer and Seeding in Grafted Dopaminergic Neurons In Vivo

Several people with Parkinson’s disease have been treated with intrastriatal grafts of fetal dopaminergic neurons. Following autopsy, 10–22 years after surgery, some of the grafted neurons contained Lewy bodies similar to those observed in the host brain. Numerous studies have attempted to explain these findings in cell and animal models. In cell culture, α-synuclein has been found to transfer from one cell to another, via mechanisms that include exosomal transport and endocytosis, and in certain cases seed aggregation in the recipient cell. In animal models, transfer of α-synuclein from host brain cells to grafted neurons has been shown, but the reported frequency of the event has been relatively low and little is known about the underlying mechanisms as well as the fate of the transferred α-synuclein. We now demonstrate frequent transfer of α-synuclein from a rat brain engineered to overexpress human α-synuclein to grafted dopaminergic neurons. Further, we show that this model can be used to explore mechanisms underlying cell-to-cell transfer of α-synuclein. Thus, we present evidence both for the involvement of endocytosis in α-synuclein uptake in vivo, and for seeding of aggregation of endogenous α-synuclein in the recipient neuron by the transferred α-synuclein. Finally, we show that, at least in a subset of the studied cells, the transmitted α-synuclein is sensitive to proteinase K. Our new model system could be used to test compounds that inhibit cell-to-cell transfer of α-synuclein and therefore might retard progression of Parkinson neuropathology

Elevated oxysterol levels in human and mouse livers reflect nonalcoholic steatohepatitis

Non-alcoholic steatohepatitis (NASH), a primary cause of liver disease, leads to complications such as fibrosis, cirrhosis, and carcinoma, but the pathophysiology of NASH is incompletely understood. Epstein Barr virus induced G protein coupled receptor 2 (EBI2) and its oxysterol ligand 7α,25-dihydroxycholesterol (7α,25-diHC) are recently discovered immune regulators. Several lines of evidence suggest a role of oxysterols in NASH pathogenesis, but rigorous testing has not been performed. We measured oxysterol levels in livers of NASH patients by liquid chromatography-mass spectrometry and tested the role of the EBI2-7α,25-diHC-system in a murine feeding model of NASH. Free oxysterol profiling in livers from NASH patients revealed a pronounced increase in 24- and 7-hydroxylated oxysterols in NASH compared to controls. Levels of 24- and 7-hydroxylated oxysterols correlated with histological NASH activity. Histological analysis of murine liver samples demonstrated ballooning and liver inflammation. No significant genotype related differences were observed in Ebi2-/- animals and animals with defects in the 7α,25-diHC synthesizing enzymes CH25H and CYP7B1 compared to wildtype littermate controls,arguing against an essential role of these genes in NASH pathogenesis. Elevated 24- and 7-hydroxylated oxysterol levels were confirmed in murine NASH liver samples. Our results suggest increased bile acid synthesis in NASH samples, as judged by enhanced level of 7α- hydroxycholest-4-en-3-one, and impaired 24S-hydroxycholesterol metabolism as characteristic biochemical changes in livers affected by NASH

Comparison of Human Primary with Human iPS Cell-Derived Dopaminergic Neuron Grafts in the Rat Model for Parkinson's Disease

Neuronal degeneration within the substantia nigra and the loss of the dopaminergic nigro-striatal pathway are the major hallmarks of Parkinson’s disease (PD). Grafts of foetal ventral mesencephalic (VM) dopaminergic (DA) neurons into the striatum have been shown to be able to restore striatal dopamine levels and to improve overall PD symptoms. However, human foetus-derived cell grafts are not feasible for clinical application. Autologous induced pluripotent stem cell (iPS cell)-derived DA neurons are emerging as an unprecedented alternative. In this review, we summarize and compare the efficacy of human iPS cell-derived DA neuron grafts to restore normal behaviour in a rat model for PD with that of human foetal primary DA neurons. The differences we observed in the efficacy to restore normal function between the 2 types of DA neuron grafts could be ascribed to intrinsic properties of the iPS cell-derived DA neurons that critically affected survival and proper neurite extension in the striatum after implantation

Acceptability and feasibility of using vaginal menstrual cups among schoolgirls in rural Nepal: a qualitative pilot study

Introduction Menstrual hygiene management can be challenging in low-income settings and among school-aged girls due to traditional beliefs, lack of knowledge and information on best hygienic practices, and limited access to appropriate and affordable menstrual hygiene products. An alternative method for menstrual hygiene management, instead of sanitary pads or tampons, is the vaginal menstrual cup. As evidence on the use of menstrual cups is relatively limited, this study aimed to explore the acceptability and feasibility of using vaginal menstrual cups among school-aged girls in Thokarpa, Sindupalchowk, Nepal. Methods This is an exploratory study based on four focus group discussions with a purposive sample of 28 schoolgirls between 13 and 19 years of age who were provided with vaginal menstrual cups in Thokarpa, Sindupalchowk, Nepal. The data were collected between February and March 2019, i.e. approximately three months after the distribution of the menstrual cup. Participants were included in the study if they had started their menstruation and never given birth. Conventional content analysis was applied. Results Most participants perceived the menstrual cup positively. Not missing a single class in school due to problems related to menstrual hygiene management was described as a major benefit. The participants found using the menstrual cup easy and convenient, and described economic and environmental advantages of using it. Cleaning the menstrual cup did not cause any problems, according to the participants. Discomforts mentioned by the participants were: pain when inserting the menstrual cup, feeling the menstrual cup sticking out of the vagina, feeling a constant urge to urinate and leakage. Concerns were related to the size, shape and texture of the menstrual cup, and that it may "get stuck" in the vagina, while relatives were said to be concerned about the use of the menstrual cup leading to reduced fertility or losing virginity. Conclusion The use of vaginal menstrual cups for menstrual hygiene management among schoolgirls in Thokarpa, Sindupalchowk, Nepal, appears feasible and acceptable, as it involves practical, economic and environmental advantages. However, the scale-up of menstrual cups will require resolving described concerns and discomforts and fostering peer and family support