Contrasting alterations to synaptic and intrinsic properties in upper-cervical superficial dorsal horn neurons following acute neck muscle inflammation

Background: Acute and chronic pain in axial structures, like the back and neck, are difficult to treat, and have incidence as high as 15%. Surprisingly, most preclinical work on pain mechanisms focuses on cutaneous structures in the limbs and animal models of axial pain are not widely available. Accordingly, we developed a mouse model of acute cervical muscle inflammation and assessed the functional properties of superficial dorsal horn (SDH) neurons.<p></p> Results: Male C57/Bl6 mice (P24-P40) were deeply anaesthetised (urethane 2.2?g/kg i.p) and the rectus capitis major muscle (RCM) injected with 40??l of 2% carrageenan. Sham animals received vehicle injection and controls remained anaesthetised for 2?hrs. Mice in each group were sacrificed at 2?hrs for analysis. c-Fos staining was used to determine the location of activated neurons. c-Fos labelling in carrageenan-injected mice was concentrated within ipsilateral (87% and 63% of labelled neurons in C1 and C2 segments, respectively) and contralateral laminae I - II with some expression in lateral lamina V. c-Fos expression remained below detectable levels in control and sham animals. In additional experiments, whole cell recordings were obtained from visualised SDH neurons in transverse slices in the ipsilateral C1 and C2 spinal segments. Resting membrane potential and input resistance were not altered. Mean spontaneous EPSC amplitude was reduced by ~20% in neurons from carrageenan-injected mice versus control and sham animals (20.63???1.05 vs. 24.64???0.91 and 25.87???1.32 pA, respectively). The amplitude (238???33 vs. 494???96 and 593???167 pA) and inactivation time constant (12.9???1.5 vs. 22.1???3.6 and 15.3???1.4?ms) of the rapid A type potassium current (IAr), the dominant subthreshold current in SDH neurons, were reduced in carrageenan-injected mice.<p></p> Conclusions: Excitatory synaptic drive onto, and important intrinsic properties (i.e., IAr) within SDH neurons are reduced two hours after acute muscle inflammation. We propose this time point represents an important transition period between peripheral and central sensitisation with reduced excitatory drive providing an initial neuroprotective mechanism during the early stages of the progression towards central sensitisation

FOXA1 mutations alter pioneering activity, differentiation and prostate cancer phenotypes.

Mutations in the transcription factor FOXA1 define a unique subset of prostate cancers but the functional consequences of these mutations and whether they confer gain or loss of function is unknown1-9. Here, by annotating the landscape of FOXA1 mutations from 3,086 human prostate cancers, we define two hotspots in the forkhead domain: Wing2 (around 50% of all mutations) and the highly conserved DNA-contact residue R219 (around 5% of all mutations). Wing2 mutations are detected in adenocarcinomas at all stages, whereas R219 mutations are enriched in metastatic tumours with neuroendocrine histology. Interrogation of the biological properties of wild-type FOXA1 and fourteen FOXA1 mutants reveals gain of function in mouse prostate organoid proliferation assays. Twelve of these mutants, as well as wild-type FOXA1, promoted an exaggerated pro-luminal differentiation program, whereas two different R219 mutants blocked luminal differentiation and activated a mesenchymal and neuroendocrine transcriptional program. Assay for transposase-accessible chromatin using sequencing (ATAC-seq) of wild-type FOXA1 and representative Wing2 and R219 mutants revealed marked, mutant-specific changes in open chromatin at thousands of genomic loci and exposed sites of FOXA1 binding and associated increases in gene expression. Of note, ATAC-seq peaks in cells expressing R219 mutants lacked the canonical core FOXA1-binding motifs (GTAAAC/T) but were enriched for a related, non-canonical motif (GTAAAG/A), which was preferentially activated by R219-mutant FOXA1 in reporter assays. Thus, FOXA1 mutations alter its pioneering function and perturb normal luminal epithelial differentiation programs, providing further support for the role of lineage plasticity in cancer progression

Black hole formation via hypercritical accretion during common envelope evolution

Neutron stars inspiralling into a stellar envelope can accrete at rates vastly exceeding the Eddington limit if the flow develops pressures high enough to allow neutrinos to radiate the released gravitational energy. It has been suggested that this hypercritical mode of accretion leads inevitably to the formation of stellar mass black holes during common envelope evolution. We study the hydrodynamics of this flow at large radii (R >> R_ns), and show that for low Mach number flows, in two dimensions, modest density gradients in the stellar envelope suffice to produce a hot, advection dominated accretion disk around the accreting object. The formation of outflows from such a disk is highly probable, and we discuss the impact of the resultant mass loss and feedback of energy into the envelope for the survival of the neutron star. Unless outflows are weaker than those inferred for well observed accreting systems, we argue that in most cases insufficient accretion occurs to force collapse to a black hole before the envelope has been ejected. This conclusions is of interest for black hole formation in general, for some models of gamma ray bursts, and for predictions of the event rate in future LIGO observations.Comment: ApJ, submitte

GLI1 genotypes do not predict basal cell carcinoma risk: a case control study

<p>Abstract</p> <p>Background</p> <p>Susceptibility to basal cell carcinoma results from complex interactions between ultraviolet radiation exposure and genetic factors. The <it>GLI1 </it>oncogene is believed to play a role in the genesis of these tumors. We determined whether <it>GLI1 </it>polymorphisms were risk factors for developing basal cell carcinoma, either alone or in combination with patterns of past sun exposure, and whether there were functional differences among different <it>GLI1 </it>haplotypes.</p> <p>Results</p> <p><it>GLI1 </it>genotypes at c.2798 and c.3298 from 201 basal cell carcinoma patients were compared to 201 age and sex-matched controls. Neither genotype nor haplotype frequencies differed between cases and controls. However, the odds of developing basal cell carcinoma on the trunk compared to the head/neck appeared somewhat lower with carriers of the c.3298GC than the CC genotype. There was no evidence for interactions between skin type, childhood sunburning, average adult sun exposure, adult sunbathing, or intermittency of sun exposure and <it>GLI1 </it>haplotype. Additionally, we found no significant differences in transcription activation or cell transforming ability among the four <it>GLI1 </it>haplotypes.</p> <p>Conclusion</p> <p>These results suggest that different <it>GLI1 </it>genotypes alone or in combination with past sun exposure patterns as assessed in this study do not affect basal cell carcinoma risk.</p

Laparoscopic repair of very large hiatus hernia with sutures versus absorbable mesh versus nonabsorbable mesh a randomized controlled trial

Author version made available in accordance with pubilsher policy. 12 month embargo applies from the date of publication (1 Feb 2015).Objective: Determine whether absorbable or non-absorbable mesh in repair of large hiatus hernias reduces the risk of recurrence, compared to suture repair. Summary Background Data: Repair of large hiatus hernia is associated with radiological recurrence rates of up to 30%, and to improve outcomes mesh repair has been recommended. Previous trials have shown less short term recurrence with mesh, but adverse outcomes limit mesh use. Methods: Multicentre prospective double blind randomized controlled trial of 3 methods of repair; sutures vs. absorbable mesh vs. non-absorbable mesh. Primary outcome - hernia recurrence assessed by barium meal X-ray and endoscopy at 6 months. Secondary outcomes - clinical symptom scores at 1, 3, 6 and 12 months. Results: 126 patients enrolled - 43 sutures, 41 absorbable mesh and 42 non-absorbable mesh. 96.0% were followed to 12 months, with objective follow-up data in 92.9%. A recurrent hernia (any size) was identified in 23.1% following suture repair, 30.8% - absorbable mesh, and 12.8% - non-absorbable mesh (p=0.161). Clinical outcomes were similar, except less heartburn at 3 & 6 months and less bloating at 12 months with non-absorbable mesh, and more heartburn at 3 months, odynophagia at 1 month, nausea at 3 & 12 months, wheezing at 6 months, and inability to belch at 12 months following absorbable mesh. The magnitude of the clinical differences were small. Conclusions: No significant differences were seen for recurrent hiatus hernia, and the clinical differences were unlikely to be clinically significant. Overall outcomes following sutured repair were similar to mesh repair

Formality and informality in the summative assessment of motor vehicle apprentices: a case study

This article explores the interaction of formal and informal attributes of competence‐based assessment. Specifically, it presents evidence from a small qualitative case study of summative assessment practices for competence‐based qualifications within apprenticeships in the motor industry in England. The data are analysed through applying an adaptation of a framework for exploring the interplay of formality and informality in learning. This analysis reveals informal mentoring as a significant element which influences not only the process of assessment, but also its outcomes. We offer different possible interpretations of the data and their analysis, and conclude that, whichever interpretation is adopted, there appears to be a need for greater capacity‐building for assessors at a local level. This could acknowledge a more holistic role for assessors; recognise the importance of assessors’ informal practices in the formal retention and achievement of apprentices; and enhance awareness of inequalities that may be reinforced by both informal and formal attributes of assessment practices

Reducing drug related deaths : a pre-implementation assessment of knowledge,barriers and enablers for naloxone distribution through general practice

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