The ExPeCT (Examining Exercise, Prostate Cancer and Circulating Tumour Cells) trial: study protocol for a randomised controlled trial

Background: Prostate cancer (PrCa) is the second most common cancer in Ireland. Many men present with locally advanced or metastatic cancer for whom curative surgery is inappropriate. Advanced cancer patients are encouraged to remain physically active and therefore there is a need to investigate how patients with metastatic disease tolerate physical activity programmes. Physical activity reduces levels of systemic inflammatory mediators and so an aerobic exercise intervention may represent an accessible and cost-effective means of ameliorating the pro-inflammatory effects of obesity and subsequently decrease poor cancer-specific outcomes in this patient population. This study will assess the feasibility and safety of introducing a structured aerobic exercise intervention to an advanced cancer population. This study will also examine if the evasion of immune editing by circulating tumour cells (CTCs) is an exercise-modifiable mechanism in obese men with prostate cancer. Methods: This international multicentre prospective study will recruit men with metastatic prostate cancer. Participants will be recruited from centres in Dublin (Ireland) and London (UK). Participants will be divided into exposed and non-exposed groups based on body mass index (BMI) ≥ 25 kg/m2 and randomised to intervention and control groups. The exercise group will undertake a regular supervised aerobic exercise programme, whereas the control group will not. Exercise intensity will be prescribed based on a target heart rate monitored by a polar heart rate monitor. Blood samples will be taken at recruitment and at 3 and 6 months to examine the primary endpoint of platelet cloaking of CTCs. Participants will complete a detailed questionnaire to assess quality of life (QoL) and other parameters at each visit. Discussion The overall aim of the ExPeCT trial is to examine the relationship between PrCa, exercise, obesity, and systemic inflammation, and to improve the overall QoL in men with advanced disease. Results will inform future work in this area examining biological markers of prognosis in advanced prostate cancer. Trial registration Clinicaltrials.gov NLM identifier: NCT02453139. Registered on 12 May 2015. This document contains excerpts from the ExPeCT trial protocol Version 1.5, 28 July 2016

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

“You’re stuck in the middle here”: a qualitative study of GPs’ experiences of managing knee pain attributed to a degenerative meniscal tear

Abstract Background Exercise is the recommended first-line therapy for a degenerative meniscal tear (DMT). Despite this, knee pain attributed to DMTs are a common presentation to specialist orthopaedic clinics. In the primary care setting, the general practitioner (GP) plays a central role in managing patients with knee pain, but to date their perspective has not been explored in relation to DMTs. This study explored GPs’ experiences of managing people with knee pain attributed to a DMT. Methods A qualitative research design was adopted and practices in the South and Mid-West of Ireland were contacted via recruitment emails circulated through professional and research networks. Interested GPs contacted the researchers via email, and purposive and snowball sampling was used for recruitment. Semi-structured interviews were conducted online or over the telephone. Interviews were digitally recorded and transcribed. Data was analysed using an inductive approach to thematic analysis. Ethical approval was granted by the Irish College of General Practitioners (ICGP_REC_21_0031). Results Seventeen semi-structured one-on-one interviews were conducted. Three main themes were identified with related subthemes: (1) GPs’ experiences of relational aspects of care, (2) GP beliefs about what constitutes best care for patients with a DMT, and (3) how GP practice is enacted within the current healthcare setting. GPs described the challenge of maintaining a strong clinical alliance, while managing perceived patient expectations of a ‘quick fix’ and advanced imaging. They reported slowing down clinical decisions and feeling ‘stuck’ with limited options when conservative treatment had failed. GPs believed that exercise should be the core treatment for DMTs and emphasised engaging patients in an active approach to recovery. Some GPs believed arthroscopy had a role in circumstances where patients didn’t improve with physiotherapy. Limited access to public physiotherapy and orthopaedic services hampered GPs’ management plans and negatively impacted patient outcomes. Conclusions GP beliefs around what constitutes best care for a DMT generally aligned with the evidence base. Nonetheless, there was sometimes tension between these beliefs and the patient’s own treatment expectations. The ability to enact their beliefs was hampered by limited access to conservative management options, sometimes leading to early escalation of care

Evidence of decreased gap junction coupling between astrocytes and oligodendrocytes in the anterior cingulate cortex of depressed suicides

International audienc

A Defined Heteromeric KV1 Channel Stabilizes the Intrinsic Pacemaking and Regulates the Efferent Code of Deep Cerebellar Nuclear Neurons to Thalamic Targets

The output of the cerebellum to the motor axis of the central nervous system is orchestrated mainly by synaptic inputs and intrinsic pacemaker activity of deep cerebellar nuclear (DCN) projection neurons. Herein, we demonstrate that the soma of these cells is enriched with KV1 channels produced by mandatory multi-merization of KV1.1, 1.2 α and KV β2 subunits. Being constitutively active, the K+ current (IKV1) mediated by these channels stabilizes the rate and regulates the temporal precision of self-sustained firing of these neurons. Placed strategically, IKV1 provides a powerful counter-balance to prolonged depolarizing inputs, attenuates the rebound excitation, and dampens the membrane potential bi-stability. Somatic location with low activation threshold render IKV1 instrumental in voltage-dependent de-coupling of the axon initial segment from the cell body of projection neurons, impeding invasion of backpropagating initial segment action potentials into the somato-dendr itic compartment. The latter also promotes the dominance of clock like somatic pace-making in driving the regenerative firing activity of these neurons, to encode time variant inputs with high fidelity. Through the use of multi-compartmental modeling and retro-axonal labeling, the physiological significance of the described functions for processing and communication of information from the lateral DCN to thalamic relay nuclei is establishedPeer reviewedFinal Accepted Versio

Identifying Sources of Faecal Contamination in a Small Urban Stream Catchment: A Multiparametric Approach

Small urban streams discharging in the proximity of bathing waters may significantly contribute to the deterioration of water quality, yet their impact may be overlooked. This study focuses on the Elm Park stream in the city of Dublin that is subject to faecal contamination by unidentified sources. The aim of the study was to identify a minimum number of “sentinel” sampling stations in an urban catchment that would provide the maximum amount of information regarding faecal pollution in the catchment. Thus, high-resolution sampling within the catchment was carried out over the course of 1 year at 11 stations. Faecal indicator bacteria were enumerated and microbial source tracking (MST) was employed to evaluate human pollution. In addition, ammonium, total oxidised nitrogen, and phosphorus levels were monitored to determine if these correlated with faecal indicator and the HF183 MST marker. In addition, the effect of severe weather events on water quality was assessed using automated sampling at one of the identified “sentinel” stations during baseflow and high flow conditions over a 24-h period. Our results show that this urban stream is at times highly contaminated by point source faecal pollution and that human faecal pollution is pervasive in the catchment. Correlations between ammonium concentrations and faecal indicator bacteria (FIB) as well as the human MST marker were observed during the study. Cluster analysis identified four “sentinel” stations that provide sufficient information on faecal pollution in the stream, thus reducing the geographical complexity of the catchment. Furthermore, ammonium levels strongly correlated with FIB and the human HF183 MST marker under high flow conditions at key “sentinel” stations. This work demonstrates the effectiveness of pairing MST, faecal indicators, and ammonium monitoring to identify “sentinel” stations that could be more rapidly assessed using real-time ammonium readouts to assess remediation efforts.</p

The neuropeptide landscape of human prefrontal cortex

Human prefrontal cortex (hPFC) is a complex brain region involved in cognitive and emotional processes and several psychiatric disorders. Here, we present an overview of the distribution of the peptidergic systems in 17 subregions of hPFC and three reference cortices obtained by microdissection and based on RNA sequencing and RNAscope methods integrated with published single-cell transcriptomics data. We detected expression of 60 neuropeptides and 60 neuropeptide receptors in at least one of the hPFC subregions. The results reveal that the peptidergic landscape in PFC consists of closely located and functionally different subregions with unique peptide/transmitter–related profiles. Neuropeptide-rich PFC subregions were identified, encompassing regions from anterior cingulate cortex/orbitofrontal gyrus. Furthermore, marked differences in gene expression exist between different PFC regions (>5-fold; cocaine and amphetamine–regulated transcript peptide) as well as between PFC regions and reference regions, for example, for somatostatin and several receptors. We suggest that the present approach allows definition of, still hypothetical, microcircuits exemplified by glutamatergic neurons expressing a peptide cotransmitter either as an agonist (hypocretin/orexin) or antagonist (galanin). Specific neuropeptide receptors have been identified as possible targets for neuronal afferents and, interestingly, peripheral blood-borne peptide hormones (leptin, adiponectin, gastric inhibitory peptide, glucagon-like peptides, and peptide YY). Together with other recent publications, our results support the view that neuropeptide systems may play an important role in hPFC and underpin the concept that neuropeptide signaling helps stabilize circuit connectivity and fine-tune/modulate PFC functions executed during health and disease

The neuropeptide landscape of human prefrontal cortex

Human prefrontal cortex (hPFC) is a complex brain region involved in cognitive and emotional processes and several psychiatric disorders. Here, we present an overview of the distribution of the peptidergic systems in 17 subregions of hPFC and three reference cortices obtained by microdissection and based on RNA sequencing and RNAscope methods integrated with published single-cell transcriptomics data. We detected expression of 60 neuropeptides and 60 neuropeptide receptors in at least one of the hPFC subregions. The results reveal that the peptidergic landscape in PFC consists of closely located and functionally different subregions with unique peptide/transmitter-related profiles. Neuropeptide-rich PFC subregions were identified, encompassing regions from anterior cingulate cortex/orbitofrontal gyrus. Furthermore, marked differences in gene expression exist between different PFC regions (&gt;5-fold; cocaine and amphetamine-regulated transcript peptide) as well as between PFC regions and reference regions, for example, for somatostatin and several receptors. We suggest that the present approach allows definition of, still hypothetical, microcircuits exemplified by glutamatergic neurons expressing a peptide cotransmitter either as an agonist (hypocretin/orexin) or antagonist (galanin). Specific neuropeptide receptors have been identified as possible targets for neuronal afferents and, interestingly, peripheral blood-borne peptide hormones (leptin, adiponectin, gastric inhibitory peptide, glucagon-like peptides, and peptide YY). Together with other recent publications, our results support the view that neuropeptide systems may play an important role in hPFC and underpin the concept that neuropeptide signaling helps stabilize circuit connectivity and fine-tune/modulate PFC functions executed during health and disease.Funding agency:  Hungarian Brain Research Program (2017-1.2.1-NKP-2017-00002) </p

Circulating Tumour Cell Numbers Correlate with Platelet Count and Circulating Lymphocyte Subsets in Men with Advanced Prostate Cancer: Data from the ExPeCT Clinical Trial (CTRIAL-IE 15-21)

Interactions between circulating tumour cells (CTCs) and platelets are thought to inhibit natural killer(NK)-cell-induced lysis. We attempted to correlate CTC numbers in men with advanced prostate cancer with platelet counts and circulating lymphocyte numbers. Sixty-one ExPeCT trial participants, divided into overweight/obese and normal weight groups on the basis of a BMI ≥ 25 or n = 29). CTC count positively correlated with absolute total lymphocyte count (r2 = 0.1709, p = 0.0258) and NK-cell count (r2 = 0.49, p 2 = 0.094, p = 0.0001). Correlation was also demonstrated within the overweight/obese group (n = 123, p n = 79, p = 0.001) and blood draw samples lacking platelet cloaking (n = 128, p n = 15) had a higher proportion of CD3+ T-lymphocytes (p = 0.0003) and lower proportions of B-lymphocytes (p = 0.0264) and NK-cells (p = 0.015) than the non-exercise group (n = 14). These findings suggest that CTCs engage in complex interactions with the coagulation cascade and innate immune system during intravascular transit, and they present an attractive target for directed therapy at a vulnerable stage in metastasis