Glioblastoma multiforme: Metabolic differences to peritumoral tissue and IDH-mutated gliomas revealed by mass spectrometry imaging.

Kampa JM, Kellner U, Marsching C, et al. Glioblastoma multiforme: Metabolic differences to peritumoral tissue and IDH-mutated gliomas revealed by mass spectrometry imaging. Neuropathology : official journal of the Japanese Society of Neuropathology. 2020;40(6):546-558.Glioblastoma multiforme (GBM) is the most common malignant primary brain tumor. High infiltration rates and poor therapy responses make it the deadliest glioma. The tumor metabolism is known to differ from normal one and is influenced through various factors which can lead to longer survival. Metabolites are small molecules (<1500Da) that display the metabolic pathways in the tissue. To determine the metabolic alterations between tumor and peritumoral tissue in human GBMs, mass spectrometry imaging (MSI) was performed on thin sections from 25 resected tumors. In addition, the GBMs were compared with six gliomas harboring a mutation in the isocitrate dehydrogenase (IDH1) gene (IDH1). With this technique, a manifold of analytes can be easily visualized on a single tissue section. Metabolites were annotated based on their accurate mass using high resolution MSI. Differences in their mean intensities in the tumor and peritumoral areas were statistically evaluated and abundances were visualized on the tissue. Enhanced levels of the antioxidants ascorbic acid, taurine, and glutathione in tumor areas suggest protective effects on the tumor. Increased levels of purine and pyrimidine metabolism compounds in GBM areas indicate the high energy demand. In accordance with these results, enhanced abundances of lactate and glutamine were detected. Moreover, decreased abundance of N-acetylaspartate, a marker for neuronal health, was measured in tumor areas. Obtained metabolic information could potentially support and personalize therapeutic approaches, hence emphasizing the suitability of MSI for GBM research. © 2020 The Authors. Neuropathology published by John Wiley & Sons Australia, Ltd on behalf of Japanese Society of Neuropathology

The back and forth of dendritic plasticity

Synapses are located throughout the often-elaborate dendritic tree of central neurons. Hebbian models of plasticity require temporal association between synaptic input and neuronal output to produce long-term potentiation of excitatory transmission. Recent studies have highlighted how active dendritic spiking mechanisms control this association. Here, we review new work showing that associative synaptic plasticity can be generated without neuronal output and that the interplay between neuronal architecture and the active electrical properties of the dendritic tree regulates synaptic plasticity

Gender differences in relationships between urban green space and health in the United Kingdom

Natural environments, or 'green spaces', have been associated with a wide range of health benefits. Gender differences in neighbourhood effects on health have been found in a number of studies, although these have not been explored in relation to green space. We conducted the first UK-wide study of the relationship between urban green space and health, and the first such study to investigate gender differences in this relationship. An ecological approach was used. Two land use datasets were used to create a proportional green space measure (% by area) at the UK Census Area Statistic ward scale. Our sample consisted of 6432 urban wards, with a total population of 28.6 million adults aged 16–64 years in 2001. We selected health outcomes that were plausibly related to green space (cardiovascular disease mortality, respiratory disease mortality and self-reported limiting long-term illness) and another that was expected to be unrelated (lung cancer mortality). Negative binomial regression models examined associations between urban green space and these health outcomes, after controlling for relevant confounders. Gender differences in these associations were observed and tested. Male cardiovascular disease and respiratory disease mortality rates decreased with increasing green space, but no significant associations were found for women. No protective associations were observed between green space and lung cancer mortality or self-reported limiting long-term illness for either men or women. Possible explanations for the observed gender differences in the green space and health relationship are gender differences in perceptions and usage of urban green spaces. We conclude that it is important not to assume uniform health benefits of urban green space for all population subgroups. Additionally, urban green space measures that capture quality as well as quantity could be more suited to studying green space and health relationships for women