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C/EBP homologous protein (CHOP), also known as DNA damage-inducible transcript 3 (DDIT3), is a member of CCAAT/enhancer-binding protein (C/EBP) family. The expression of CHOP is upregulated during unfolded protein response (UPR), and sustained CHOP activity plays an important role in UPR-induced apoptosis. MicroRNA-616 is localized in an intron of the CHOP gene. However, regulation of miR-616 expression during UPR and its function in breast cancer is not clearly understood. We show that miR-5p/-3p arms of miR-616 are expressed with levels of 5p arm higher than 3p arm. During conditions of UPR, the expression of miR-5p and miR-3p arms of miR-616 and its host gene (CHOP) was concordantly increased primarily in a PERK-dependent manner. We show that ectopic expression of miR-616 significantly suppressed cell growth and colony formation, whereas knockout of miR-616 increased it. We identified that MYC proto-oncogene (c-MYC) gene is repressed during the UPR and targeted by miR-616. Further, we show that expression of miR-616 and CHOP is downregulated in human breast cancer, where expression of miR-616 was associated with poor overall survival (OS) in luminal A subtype and better OS HER2 subtype of breast cancer. In summary, our results suggest a dual function for the DDIT3 locus, where CHOP protein and miR-616 can co-operate to regulate cancer progression.

SummaryBackgroundCoagulase Negative Staphylococci (CoNS) are responsible for 80-90 % of catheter related sepsis in neonates which can cause life threatening and damaging effects. NICUs within the UK use various practices to decolonise neonates to prevent infection ranging from regular full body bathing to localised skin decontamination before insertion of indwelling devices. There is a disparity in bathing practices for infants admitted onto neonatal units, with some choosing to regularly bathe infants and others not, and some routinely washing with skin antiseptics, and others not.AimTo compare the abundance of CoNS within two UK NICUs with different approaches to skin bathing and to test their tolerances to antiseptics.MethodsA collection of CoNS from two UK based NICUs with differing bathing routines for neonates were collated and tested for susceptibility to the antiseptics in use, octenidine and chlorhexidine.FindingsRegular bathing of neonates in octenidine did not decrease the abundance of organisms on neonatal skin. Isolates from the unit where octenidine was in frequent use did not show any increased antiseptic tolerance. Isolates from the unit where regular bathing was not routine practice were less susceptible to both antiseptics.ConclusionFrequent whole-body skin washing with octenidine does not appear to result in a lasting reduction in numbers of organisms found on the skin but also does not appear to select for antiseptic tolerant CoNS.

Background: Lymphocyte predominant breast cancers (LPBC) account for 5-30% of TNBCs; 65-80% of TNBCs have low/moderate levels of sTILs and 15-20% have no lymphocyte infiltration. TNBCs with high stromal tumor infiltrating lymphocytes (sTILs) have higher rates of pathological complete response (pCR) with anthracycline-taxane (AT) neoadjuvant chemotherapy (NACT), but the effect of carboplatin (Cb) is unclear. In GeparSixto, Cb increased pCR rates in LPBC but there was no interaction between LPBC and Cb in TNBCs. This study examines the predictive role of sTILs in TNBCs, focusing on the association between sTILs and pCR with and without Cb based NACT. Methods: Patients diagnosed with TNBC and treated with NACT in University Hospital Galway, Ireland from 2004-2016 were identified. Patients were treated with a carboplatin-anthracycline-taxane regimen (Cb-AT) (n=30) or an AT regimen (n=54). As per the International TILs Working Group, sTILs were scored on digitized slides of full-face tumor sections from diagnostic needle core biopsies. sTILs were categorized as 0-10%; 11-25%; 26-49%; ≥50% (LPBC). Odds ratio (OR) was calculated using non-pCR as the baseline. pCR was defined as ypT0/isN0. Results: Eighty-eight (n=88) cases with sufficient sTILs for analysis were identified. The median sTIL count was 12.5% (range 0-75%): 50% of cases (n=44) had sTILs 0-10%; 25% (n=22) had sTILs 11-25%; 14% (n=12) had sTILs 26-49% and 11% (n=10) had sTILs ≥50%. Cases with sTILs >10% had higher rates of pCR compared to those with sTILs ≤10% (52% vs 29%; p=0.021). In cases treated with an AT regimen, tumors with sTILs >10% had higher pCR rates than those with sTILs ≤10% (46% vs 12%; p=0.005). In cases treated with a Cb-AT regimen, there was no difference in pCR rates between sTILs >10% tumors and sTILs ≤10% tumors (60% vs 53%; p=0.500). In this cohort, pCR rates were higher in LPBC compared to non-LPBCs (80% vs 36%; p=0.010). In cases treated with AT, pCR rates were higher in LPBC than non-LPBC (83% vs 23%; p=0.007). However, in cases treated with Cb-AT, there were no differences in pCR rates between LPBC and non-LPBC (67% vs 56%; p=0.603). In LPBC, the choice of chemotherapy did not affect pCR rates: 67% vs 83% for Cb-AT and AT regimens respectively (p=0.583). In non-LPBC, pCR rates increased with Cb: 56% vs 23% for Cb-AT and AT regimens respectively (p=0.005). By univariate analysis, there was a significant association between sTILs and pCR. The association was greatest in LPBC (OR 0.14; p=0.016) and remained significant in those treated with AT (OR 0.06; p=0.014) but not in cases treated with Cb-AT (OR 0.63; p=0.714). In a multivariable model, with tumor grade and Cb use as co-variables, LPBC was independently associated with pCR (OR0.14; p=0.030). In cases treated with AT, sTILs were associated with pCR (OR 0.18, p=0.019 for sTILs >10%; OR 0.08, p=0.029 for LPBC). In cases treated with Cb-AT, sTILs were not associated with pCR (p=0.372 and p=0.622 for sTILs >10% and LPBC respectively). Conclusions: In TNBC, sTILs are predictive of response to NACT: as sTILs increase, pCR rates increase. The likelihood of a pCR increased by 86% for LPBC vs non-LPBC. The effect of sTILs on pCR was most notable in LPBC treated with AT based NACT where the odds of a pCR increased by 94%. In cases treated with Cb-AT, there was no association between sTILs and pCR. This study suggests that tumors with high sTILs are more chemosensitive than tumors with low sTILs. High sTIL tumors had high pCR rates with AT based NACT but the addition of Cb did not increase pCR rates. Cb-AT NACT could be reserved for patients with low sTIL tumors, in order to increase the rates of pCR in that subgroup, who had low rates of pCR in this study. In the future, sTILs could be used as a predictive biomarker to guide chemotherapy selection. Citation Format: Elaine M Walsh, Mark O'Loughlin, Aliaa Shalaby, Mark Webber, Michael J Kerin, Sharon A Glynn, Grace Callagy, Maccon M Keane. Pathological complete response after carboplatin-based neoadjuvant chemotherapy in triple negative breast cancer: The importance of stromal tumor infiltrating lymphocytes as a predictive biomarker [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-10-11.

A method was developed to expedite the imaging of diatoms by optimizing their orientation. This quick technique puts grooves into a SEM stub so that as the diatoms are laid down they either land on the flat surface or in a variety of positions in the grooves, thereby reducing time required to capture taxonomically critical features.

Trimethoprim and sulfamethoxazole are used commonly together as cotrimoxazole for the treatment of urinary tract and other infections. The evolution of resistance to these and other antibacterials threatens therapeutic options for clinicians. We generated and analysed a chemical-biology-whole-genome data set to predict new targets for antibacterial combinations with trimethoprim and sulfamethoxazole. For this we used a large transposon mutant library in Escherichia coli BW25113 where an outward-transcribing inducible promoter was engineered into one end of the transposon. This approach allows regulated expression of adjacent genes in addition to gene inactivation at transposon insertion sites, a methodology that has been called TraDIS-Xpress. These chemical genomic data sets identified mechanisms for both reduced and increased susceptibility to trimethoprim and sulfamethoxazole. The data identified that over-expression of FolA reduced trimethoprim susceptibility, a known mechanism for reduced susceptibility. In addition, transposon insertions into the genes tdk, deoR, ybbC, hha, ldcA, wbbK and waaS increased susceptibility to trimethoprim and likewise for rsmH, fadR, ddlB, nlpI and prc with sulfamethoxazole, while insertions in ispD, uspC, minC, minD, yebK, truD and umpG increased susceptibility to both these antibiotics. Two of these genes’ products, Tdk and IspD, are inhibited by AZT and fosmidomycin respectively, antibiotics that are known to synergise with trimethoprim. Thus, the data identified two known targets and several new target candidates for the development of co-drugs that synergise with trimethoprim, sulfamethoxazole or cotrimoxazole. We demonstrate that the TraDIS-Xpress technology can be used to generate information-rich chemical-genomic data sets that can be used for antibacterial development.

Stromal tumour infiltrating lymphocytes (sTILs) are a strong prognostic marker in triple negative breast cancer (TNBC). Consistency scoring sTILs is good and was excellent when an internet-based scoring aid developed by the TIL-WG was used to score cases in a reproducibility study. This study aimed to evaluate the reproducibility of sTILs assessment using this scoring aid in cases from routine practice and to explore the potential of the tool to overcome variability in scoring. Twenty-three breast pathologists scored sTILs in digitized slides of 49 TNBC biopsies using the scoring aid. Subsequently, fields of view (FOV) from each case were selected by one pathologist and scored by the group using the tool. Inter-observer agreement was good for absolute sTILs (ICC 0.634, 95% CI 0.539–0.735, p &lt, 0.001) but was poor to fair using binary cutpoints. sTILs heterogeneity was the main contributor to disagreement. When pathologists scored the same FOV from each case, inter-observer agreement was excellent for absolute sTILs (ICC 0.798, 95% CI 0.727–0.864, p &lt, 0.001) and good for the 20% (ICC 0.657, 95% CI 0.561–0.756, p &lt, 0.001) and 40% (ICC 0.644, 95% CI 0.546–0.745, p &lt, 0.001) cutpoints. However, there was a wide range of scores for many cases. Reproducibility scoring sTILs is good when the scoring aid is used. Heterogeneity is the main contributor to variance and will need to be overcome for analytic validity to be achieved.

Breast cancer is stratified into four distinct clinical subtypes, using three key biomarkers (Her2/Neu gene status, Estrogen and Progesterone receptor status). However, each subtype is a heterogeneous group, displaying significant variation in survival rates and treatment response. New biomarkers are required to provide more precise stratification of breast cancer cohorts to inform personalised treatment options/predict outcomes. Tip60 is a member of the MYST sub-family of histone acetyltransferases (HATs), and is directly involved in genome maintenance, gene regulation and DNA damage response/repair pathways (key chemotherapeutic influencing mechanisms). We aimed to determine if quantifying Tip60 staining patterns improved breast cancer stratification. We defined Tip60 protein in vivo, quantifying location (cytoplasmic, nuclear), percent of cells and staining intensity in a breast cancer tissue microarray (n = 337). A significant association of specific Tip60 staining patterns with breast cancer subtype, ER or PR status and Tumour grade was found. Importantly, low Tip60 mRNA expression correlated with poor overall survival and relapse free survival. We found Tip60 is a biomarker able to stratify breast cancer patients, and low Tip60 expression is a significant risk factor indicating a higher chance of disease reoccurrence. This work highlights Tip60 regulation as a key factor influencing the development of breast cancer.

The cost of enabling connectivity in Noisy-Intermediate-Scale-Quantum devices is an important factor in determining computational power. We have created a qubit routing algorithm which enables efficient global connectivity in a previously proposed trapped ion quantum computing architecture. The routing algorithm was characterized by comparison against both a strict lower bound, and a positional swap based routing algorithm. We propose an error model which can be used to estimate the achievable circuit depth and quantum volume of the device as a function of experimental parameters. We use a new metric based on quantum volume, but with native two qubit gates, to assess the cost of connectivity relative to the upper bound of free, all to all connectivity. The metric was also used to assess a square grid superconducting device. We compare these two architectures and find that for the shuttling parameters used, the trapped ion design has a substantially lower cost associated with connectivity., Comment: 12 pages

// Pablo Garrido 1, 7 , Aliaa Shalaby 1 , Elaine M. Walsh 1 , Nessa Keane 1 , Mark Webber 1 , Maccon M. Keane 2 , Francis J. Sullivan 3 , Michael J. Kerin 4 , Grace Callagy 1 , Aideen E. Ryan 5, 6 and Sharon A. Glynn 1, 3, 7 1 Discipline of Pathology, Lambe Institute for Translational Research, School of Medicine, National University of Ireland Galway, Galway, Republic of Ireland 2 Medical Oncology, Galway University Hospital, Galway, Republic of Ireland 3 Prostate Cancer Institute, National University of Ireland Galway, Galway, Republic of Ireland 4 Discipline of Surgery, Lambe Institute for Translational Research, School of Medicine, National University of Ireland Galway, Galway, Republic of Ireland 5 Discipline of Pharmacology and Therapeutics, Lambe Institute for Translational Research, School of Medicine, National University of Ireland Galway, Galway, Republic of Ireland 6 Regenerative Medicine Institute (REMEDI), Biomedical Sciences, National University of Ireland Galway, Galway, Republic of Ireland 7 Apoptosis Research Centre, National University of Ireland Galway, Galway, Republic of Ireland Correspondence to: Sharon A. Glynn, email: sharon.glynn@nuigalway.ie Keywords: triple negative breast cancer, EGFR, inflammation, metastasis, nitric oxide Received: January 17, 2017 Accepted: July 03, 2017 Published: July 26, 2017 ABSTRACT Inflammation is implicated in triple negative breast cancer (TNBC) progression. TNBC carries a worse prognosis than other breast cancer subtypes, and with the clinical and molecular heterogeneity of TNBC, there is a lack of effective therapeutic targets available. Identification of molecular targets for TNBC subtypes is crucial towards personalized patient stratification. Inducible nitric oxide synthase (iNOS) has been shown to induce p53 mutation accumulation, basal-like gene signature enrichment and transactivation of the epidermal growth factor receptor (EGFR) via s-nitrosylation. Herein we report that iNOS is associated with disease recurrence, distant metastasis and decreased breast cancer specific survival in 209 cases of TNBC. Employing TNBC cell lines representing normal basal breast, and basal-like 1 and basal-like 2 tumors, we demonstrate that nitric oxide (NO) induces EGFR-dependent ERK phosphorylation in basal-like TNBC cell lines. Moreover NO mediated cell migration and cell invasion was found to be dependent on EGFR and ERK activation particularly in basal-like 2 TBNC cells. This occurred in conjunction with NF-κB activation and increased secretion of pro-inflammatory cytokines IL-8, IL-1β and TNF-α. This provides substantial evidence for EGFR as a therapeutic target to be taken into consideration in the treatment of a specific subset of basal-like TNBC overexpressing iNOS.

We present a new database, specifically devoted to ROS homeostasis regulated proteins. This database replaced our previous database, the PeroxiBase, which was focused only on various peroxidase families. The addition of 20 new protein families related with ROS homeostasis justifies the new name for this more complex and comprehensive database as RedoxiBase.Besides enlarging the focus of the database, new analysis tools and functionalities have been developed and integrated through the web interface, with which the users can now directly access to orthologous sequences and see the chromosomal localization of sequences when available.OrthoMCL tool, completed with a post-treatment process, provides precise predictions of orthologous gene groups for the sequences present in this database. In order to explore and analyse orthogroups results, taxonomic visualization of organisms containing sequence of a specific orthogroup as well as chromosomal distribution of the orthogroup with one or two organisms have been included. Keywords: Catalase, Peroxidases, Oxido-reductases, Multigenic family, ROS homeostasis

Background Argonaute-2 (Ago2) is an essential component of microRNA biogenesis implicated in tumourigenesis. However Ago2 expression and localisation in breast cancer remains undetermined. The aim was to define Ago2 expression (mRNA and protein) and localisation in breast cancer, and investigate associations with clinicopathological details. Methods Ago2 protein was stained in breast cancer cell lines and tissue microarrays (TMAs), with intensity and localization assessed. Staining intensity was correlated with clinicopathological details. Using independent databases, Ago2 mRNA expression and gene alterations in breast cancer were investigated. Results In the breast cancer TMAs, 4 distinct staining intensities were observed (Negative, Weak, Moderate, Strong), with 64.2% of samples stained weak or negatively for Ago2 protein. An association was found between strong Ago2 staining and, the Her2 positive or basal subtypes, and between Ago2 intensity and receptor status (Estrogen or Progesterone). In tumours Ago2 mRNA expression correlated with reduced relapse free survival. Conversely, Ago2 mRNA was expressed significantly lower in SK-BR-3 (HER2 positive) and BT-20 (Basal/Triple negative) cell lines. Interestingly, high levels of Ago2 gene amplification (10–27%) were observed in breast cancer across multiple patient datasets. Importantly, knowledge of Ago2 expression improves predictions of breast cancer subtype by 20%, ER status by 15.7% and PR status by 17.5%. Conclusions Quantification of Ago2 improves the stratification of breast cancer and suggests a differential role for Ago2 in breast cancer subtypes, based on levels and cellular localisation. Further investigation of the mechanisms affecting Ago2 dysregulation will reveal insights into the molecular differences underpinning breast cancer subtypes. Electronic supplementary material The online version of this article (10.1186/s12885-019-5884-x) contains supplementary material, which is available to authorized users.

Through a consideration of policy towards the Israeli-Palestinian conflict, this article examines the autonomy and effectiveness of the European Union (EU) as an actor. We discuss first the criteria by which autonomy and effectiveness can be judged and then consider these by reference to EU policy since the formation of the Quartet in 2002. We argue that the EU has been effective in articulating a consistent and clear set of policies on Israel-Palestine. While this has placed it on-side with US-led initiatives to foster a solution to the conflict, we regard such an alignment as consistent with EU autonomy. These findings allow us to make qualified but still positive comments on the emerging EU Global Strategy. The Israeli-Palestinian conflict certainly demonstrates the limitations of EU external action but in affirming its credentials as an autonomous partner of the United States, the EU is less ineffectual than some commentators claim.

In the post-cold-war period, NATO’s mission has shifted from static territorial defence against a well-defined adversary to expeditionary missions against ill-defined adversaries along the entire conflict spectrum. We trace the evolution of NATO security strategies and the attendant changes in allied threat perception, purpose, and force structure, the range and kinds of military operations between 1990 and 2016, and military exercises undertaken after the Russian annexation of Crimea. We then assess allied contributions to those operations (burden- and risk-sharing) and the selective participation of allies in operations (risk-assuming and risk-shirking). A final substantive concern is the growing capabilities gap among the allies, its implications for future allied operations, and its consequences for the alliance. The conclusion addresses the key question facing the alliance: should NATO abandon expeditionary operations and return to static territorial defence consistent with the original intent of the North Atlantic Treaty?

Purpose The rate of pathological complete response (pCR) for patients with triple negative breast cancer (TNBC) is increased when carboplatin is added to neo-adjuvant chemotherapy (NACT). However, while phase III trial data showing a survival benefit are awaited, carboplatin is not yet standard-of-care for TNBC. The aim of this study was to examine the rate of pCR and the outcome for those treated with carboplatin and to examine the predictors of response to therapy. Methods The retrospective series comprised 333 consecutive patients with TNBC (median follow-up time, 43 months). Adjuvant chemotherapy was given to 51% (n = 168) of patients and 29% (n = 97) received anthracycline–taxane NACT with carboplatin given to 9% (n = 31) of patients. Results Overall, 25% (n = 78) of patients experienced a breast cancer recurrence and 22% (n = 68) died from disease. A pCR breast and pCR breast/axilla was more common in those who received carboplatin (n = 18, 58% and n = 17, 55%, respectively) compared those who did not (n = 23, 36% and n = 18, 28%, respectively) (p = 0.041 and p = 0.011, respectively). By multivariable analysis, carboplatin and high tumor grade were independent predictors of pCR breast/axilla (ORnon-pCR = 0.17; 95% CI 0.06–0.54; p = 0.002; and ORnon-pCR = 0.05, 95% CI 0.01–0.27; p

e12085 Background: High numbers of sTILs are predictive of pCR in TNBCs. This study examines the role of sTILs as a predictive biomarker for carboplatin (Cb) based NACT. Methods: sTILs were scored on 88 pre NACT TNBC biopsies as per the International TILs Working Group and were scored as continuous and categorical variables: 0-10%; 11-25%; 26-49%; ≥50%. OR was calculated using non-pCR as baseline parameter. Results: Patients with sTILs > 10% had increased pCR rates compared to those with sTILs ≤10%: pCR breast (B) (61% vs 31% p = 0.004); pCR breast/axilla (BA) (52% vs 29% p = 0.021). In those treated with Cb, there were no differences in pCR B between sTILs > 10% or ≤10% (67% vs 53%; p = 0.355) or pCR BA (60% vs 53%; p = 0.500). In those who did not receive Cb, sTILs > 10% had increased pCR B (57% vs 15%; p = 0.002) and pCR BA (46% vs 12%; p = 0.005) compared to sTILs ≤10%. Similar trends were seen with sTILs > 25% and ≥50%: differences were seen in patients who did not receive Cb, but not in those treated with Cb. In LPBCs, the addition of Cb did not significantly increase pCR rates: 67% vs 83% for Cb and non-Cb regimens (p = 0.583). In non-LPBC, pCR rates were increased with Cb: pCR B 59% vs 31% (p = 0.017), and pCR BA 56% vs 23% (p = 0.005) for Cb and non-Cb regimens. The association between sTILs and pCR was significant in multivariable models adjusting for grade and Cb. In patients who did not receive Cb (n = 54), increasing sTILs were associated with increased pCR B (OR 0.15 p = 0.004; OR 0.27 p = 0.039; OR 0.10 p = 0.05 for > 10%, > 25%, ≥50%) and pCR BA (OR 0.18 p = 0.019; OR 0.08 p = 0.029 for > 10%, ≥50%). In patients treated with Cb (n = 30), increasing sTILs were not associated with pCR B (OR 1.97 p = 0.581; OR 0.27 p = 0.334; OR 0.50 p = 0.719) or pCR BA (OR 2.93 p = 0.372; OR 0.79 p = 0.831; OR 0.40 p = 0.622 for > 10%, > 25%, ≥50%). Conclusions: sTILs are predictive of pCR: as sTILs increase, pCR rates increase. Tumors with high sTILs had high pCR rates to anthracycline-taxane (AT) NACT. The effect of increasing sTILs on pCR was most notable in patients who did not receive Cb based NACT, suggesting that tumors with high sTILs are inherently sensitive to AT based chemotherapy. Intensifying NACT with Cb could be used to increase pCR rates in patients with low sTILs. sTILs should be explored as a biomarker to intensify chemotherapy in those with low sTILs, and to de-escalate chemotherapy in tumors with high sTILs.

Abstract. This article examines the EU’s most prominent policy tool (short of further enlargement) intended to help stabilize and secure relations with its bordering states: the European Neighbourhood Policy (ENP). Dealing with the problem of regional stabilization has been a central rationale of the ENP and in what follows we consider how the ENP’s concern with this problem has been pursued through the framework of political dialogue with partners, focusing particularly on cooperation in external relations. There are undoubted benefits which the ENP brings to this policy domain, however the initiative is also saddled with three sets of problems. The first relates to the question of local relevance and ‘value-added’, and is a concern largely for the ENP partners. The second is the challenge of policy coherence and is played out at the EU level and among EU Member States. The third is how the ENP relates to important regional actors (principally the USA and Russia) who have the potential to both facilitate and frustrate the initiative. These three challenges frame the context for two brief regional snapshots of the ENP in action, looking at EU security relations with the South Caucasus (and Georgia more specifically) and the Middle East.

We present a linear stability analysis of viscous, pressure-driven flow in an annular pipe with a moving core. The core moves with constant speed along its axis and rotates with constant angular frequency. At both boundaries the fluid obeys slip boundary conditions. Our numerical results highlight the important role of asymmetric perturbations in the instability of the system. Boundary slip is seen to be stabilizing, as has been observed for other types of parallel flows. We show that motion of the solid core with respect to the outer cylinder causes the neutral curve to split into two distinct curves. In particular, we show that rotation has a surprising destabilizing effect.

We investigate the influence of slip boundary conditions on the onset of Benard convection in an infinite fluid layer. It is shown that the critical Rayleigh number is a decreasing function of the slip length, and therefore boundary slip is seen to have a destabilizing effect. Chebyshev-tau and compound matrix formulations for solving the eigenvalue problem are presented.

Not all neuropathic pain patients gain relief from current therapies that include the anticonvulsant, gabapentin, thought to modulate calcium channel function. We report a neural circuit that is permissive for the effectiveness of gabapentin. Substance P-saporin (SP-SAP) was used to selectively ablate superficial dorsal horn neurons expressing the neurokinin-1 receptor for substance P. These neurons project to the brain as shown by retrograde labelling and engage descending brainstem serotonergic influences that enhance spinal excitability via a facilitatory action on 5HT(3) receptors. We show the integrity of this pathway following nerve injury contributes to the behavioural allodynia, neuronal plasticity of deep dorsal horn neurons and the injury-specific actions of gabapentin. Thus SP-SAP attenuated the tactile and cold hypersensitivity and abnormal neuronal coding (including spontaneous activity, expansion of receptive field size) seen after spinal nerve ligation. Furthermore the powerful actions of gabapentin after neuropathy were blocked by either ablation of NK-1 expressing neurones or 5HT(3) receptor antagonism using ondansetron. Remarkably, 5HT(3) receptor activation provided a state-dependency (independent of that produced by neuropathy) allowing GBP to powerfully inhibit in normal uninjured animals. This circuit is therefore a crucial determinant of the abnormal neuronal and behavioural manifestations of neuropathy and importantly, the efficacy of gabapentin. As this spino-bulbo-spinal circuit contacts areas of the brain implicated in the affective components of pain, this loop may represent a route by which emotions can influence the degree of pain in a patient, as well as the effectiveness of the drug treatment. These hypotheses are testable in patients.

We have used differential display to profile and compare the mRNAs expressed in the hippocampus of freely moving animals after the induction of long-term potentiation (LTP) at the perforant path-dentate gyrus synapse with control rats receiving low-frequency stimulation. We have combined this with in situ hybridization and have identified A-kinase anchoring protein of 150 kDa (AKAP-150) as a gene selectively up-regulated during the maintenance phase of LTP. AKAP-150 mRNA has a biphasic modulation in the dentate gyrus following the induction of LTP. The expression of AKAP-150 was 29% lower than stimulated controls 1 h after the induction of LTP. Its expression was enhanced 3 (50%), 6 (239%) and 12 h (210%) after induction, returning to control levels by 24 h postinduction. The NMDA receptor antagonist CPP blocked the tetanus-induced modulation of AKAP-150 expression. Interestingly, strong generalized stimulation produced by electroconvulsive shock did not increase the expression of AKAP-150. This implies that the AKAP-150 harbours a novel property of selective responsiveness to the stimulation patterns that trigger NMDA-dependent LTP in vivo. Its selective up-regulation during LTP and its identified functions as a scaffold for protein kinase A, protein kinase C, calmodulin, calcineurin and ionotropic glutamate receptors suggest that AKAP-150 encodes is an important effector protein in the expression of late LTP.