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Developing sensitive and reliable methods to distinguish normal and abnormal brain states is a key neuroscientific challenge. Topological Data Analysis, despite its relative novelty, already generated many promising applications, including in neuroscience. We conjecture its prominent tool of persistent homology may benefit from going beyond analysing structural and functional connectivity to effective connectivity graphs capturing the direct causal interactions or information flows. Therefore, we assess the potential of persistent homology to directed brain network analysis by testing its discriminatory power in two distinctive examples of disease-related brain connectivity alterations epilepsy and schizophrenia. We estimate connectivity from functional magnetic resonance imaging and electrophysiology data, employ Persistent Homology and quantify its ability to distinguish healthy from diseased brain states by applying a support vector machine to features quantifying persistent homology structure. We show howology, this could be due to notorious technical problems of accurate effective connectivity estimation.Our perception of the external world is influenced by internal bodily signals. For example, we recently showed that timing of stimulation along the cardiac cycle and spontaneous fluctuations of heartbeat-evoked potential (HEP) amplitudes influence somatosensory perception and the associated neural processing (Al et al., 2020). While cardiac phase affected detection sensitivity and late components of the somatosensory-evoked potentials (SEPs), HEP amplitudes affected detection criterion and both early and late SEP components. In a new EEG study, we investigate whether these results are replicable in a modified paradigm, which includes two succeeding temporal intervals. In one of the intervals, subjects received a weak electrical finger stimulation and reported first whether they detected any stimulation and then allocated the stimulus to one of the two intervals. Our results confirm the previously reported cardiac cycle and prestimulus HEP effects on somatosensory perception and evoked potentials. In addition, we obtained two new findings. Source analyses in this and our original study show that the increased likelihood of conscious perception goes along with HEP fluctuations in parietal and posterior cingulate regions, known to play important roles in interoceptive processes. Furthermore, HEP amplitudes were shown to decrease when subjects engaged in the somatosensory task compared to a resting state condition. Our findings are consistent with the view that HEP amplitudes are a marker of interoceptive (versus exteroceptive) attention and provide a neural underpinning for this view.Mutations in KRAS frequently occur in human cancer and are especially prevalent in pancreatic ductal adenocarcinoma (PDAC), where they have been shown to promote aggressive phenotypes. However, targeting this onco-protein has proven to be challenging, highlighting the need to further identify the various mechanisms used by KRAS to drive cancer progression. Here, we considered the role played by exosomes, a specific class of extracellular vesicles (EVs) derived from the endocytic cellular trafficking machinery, in mediating the ability of KRAS to promote cell survival. We found that exosomes isolated from the serum of PDAC patients, as well as from KRAS-transformed fibroblasts and pancreatic cancer cells, were all highly enriched in the cell survival protein Survivin. Exosomes containing Survivin, upon engaging serum-starved cells, strongly enhanced their survival. Moreover, they significantly compromised the effectiveness of the conventional chemotherapy drug paclitaxel, as well as a novel therapy that combines an ERK inhibitor with chloroquine, which is currently in clinical trials for PDAC. The survival benefits provided by oncogenic KRAS-derived exosomes were markedly reduced when depleted of Survivin using siRNA or upon treatment with the Survivin inhibitor YM155. Taken together, these findings demonstrate how KRAS mutations give rise to exosomes that provide a unique form of intercellular communication to promote cancer cell survival and therapy resistance, as well as raise interesting possibilities regarding their potential for serving as therapeutic targets and diagnostic markers for KRAS-dependent cancers.This study aimed to evaluate the effects of repeated bimodal transcranial direct current stimulation (tDCS) on alcohol consumption and immunohistological and neurochemical parameters in nerve-injured rats. Forty-eight adult male Wistar rats were distributed into six groups control, neuropathic pain (NP) + sham-tDCS, NP + alcohol + sham-tDCS, alcohol + sham-tDCS, alcohol + tDCS, and NP + alcohol + tDCS. NP is induced by chronic sciatic nerve constriction (CCI). The rats were exposed to a 10% alcohol solution by voluntary consumption for 14 days. From the 16th day after surgery, bimodal tDCS was applied for 20 min/day for 8 days. Brain structures were collected to evaluate the number of neuropeptide Y (NPY)-positive neurons, neurites, and argyrophilic grains by immunohistochemistry, and brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), interleukin (IL)-6, and IL-10 by ELISA. buy Exendin-4 Nerve-injured rats showed a progressive increase in alcohol consumption compared to the non-injured rats. In addition, there was a reduction in voluntary alcohol consumption over time induced by tDCS. Alcohol exposure, chronic pain, and tDCS treatment modulated the central NPY immunoreactivity. tDCS increased the cerebellar levels of IL-6 and IL-10, and CCI and/or tDCS reduced striatal BDNF levels. The current data suggest that tDCS could be a promising non-pharmacological adjuvant to treat patients with chronic pain who use alcohol to relieve their symptoms.Exposing mammals to adverse social environments early in life can affect brain development in ways that alter adult behaviour. For example, chronic, early-life social isolation (CELSI) has been found to cause novelty-induced hyperactivity, impaired pre-pulse inhibition, and enhanced anxiety-related behaviour. Although the molecular mechanism(s) underlying the embedding of CELSI have not been fully elucidated, evidence suggests changes in the level of excitatory neurotransmission and neurotrophic factor signalling may be quite important. Since much of the work in this area has focused upon mRNA-level analyses, and has shown variable responses across both brain region and animal sex, our study aimed to explore the impact of CELSI on the expression of two important plasticity-related proteins (Tropomyosin receptor kinase B and the GluN2B subunit of the NMDA receptor) in the pre-frontal cortex and hippocampus of both male and female rats. We observed that the expression of both proteins was clearly changed by CELSI, but that the effect occurred in a sex (but not region) specific manner.