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The modern-day athlete participating in elite sports is exposed to high training loads and increasingly saturated competition calendar. Emerging evidence indicates that inappropriate load management is a significant risk factor for acute illness and the overtraining syndrome. The IOC convened an expert group to review the scientific evidence for the relationship of load-including rapid changes in training and competition load, competition calendar congestion, psychological load and travel-and health outcomes in sport. This paper summarises the results linking load to risk of illness and overtraining in athletes, and provides athletes, coaches and support staff with practical guidelines for appropriate load management to reduce the risk of illness and overtraining in sport. These include guidelines for prescription of training and competition load, as well as for monitoring of training, competition and psychological load, athlete well-being and illness. In the process, urgent research priorities were identified., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

Anterior cruciate ligament (ACL) reconstruction is one of the most extensively studied surgical procedures in orthopaedics. The importance of this ligament for knee function and stability has been widely studied. For athletes who participate in activities involving cutting, twisting, and running, surgical reconstruction of the ACL has become the standard of care. However, there is much debate regarding the techniques involved in ACL reconstruction, including graft choice, technique of drilling the femoral tunnel, and single- versus double-bundle reconstruction. In recent studies, ACL femoral tunnel drilling via a medial parapatellar or accessory anteromedial portal provides a more anatomic graft placement than transtibial femoral drilling. Long-term outcomes of these techniques have not been widely studied. This article details our technique for ACL reconstruction with bone-patellar tendon-bone autograft and a medial parapatellar portal.

Objective: To synthesize and critically evaluate all available evidence investigating whether localized, provoked vestibulodynia is associated with a specific inflammatory profile at both a local and a systemic level., Data Sources: Comprehensive electronic searches were performed in MEDLINE, EMBASE, Scopus, PubMed, Web of Science, Cumulative Index to Nursing and Allied Health Literature, the Cochrane Collaboration databases, and ClinicalTrials.gov. The search strategy was developed using MeSH terms related to localized, provoked vestibulodynia, and inflammatory markers., Methods of Study Selection: Two independent investigators screened titles and abstracts and performed data extraction and risk of bias assessments. Studies were included if they reported at least one baseline inflammatory marker in women with localized, provoked vestibulodynia and compared them with healthy women. Reference lists from published reviews on localized, provoked vestibulodynia were screened for additional studies., Tabulation, Integration, and Results: There were 1,619 studies identified. Eighteen studies met the inclusion criteria, including 400 women with localized, provoked vestibulodynia and 212 healthy women in a control group. Risk of bias assessment revealed that the methodologic quality was generally low. Fifteen studies investigated local inflammation and three studies investigated systemic inflammation. On a local level, the number of mast cells expressed in vestibular tissues was greater in women with localized, provoked vestibulodynia expressed than in women in the control group. Several studies reported undefined inflammatory infiltrate in vestibular tissues to a greater level in women with localized, provoked vestibulodynia than in women in the control group. Systemically, levels of natural killer cells were lower in women with localized, provoked vestibulodynia than in women in the control group. There were no systemic differences in systemic interferon-α and interferon-υ levels between groups., Conclusion: There is limited and contradictory evidence regarding the characteristics of local and systemic inflammation in women with localized, provoked vestibulodynia.

This work reports on the development of an optical fiber based probe for in vivo measurements of brain temperature. By utilizing a thin layer of rare-earth doped tellurite glass on the tip of a conventional silica optical fiber a robust probe, suitable for long-term in vivo measurements of temperature can be fabricated. This probe can be interrogated using a portable optical measurement setup, allowing for measurements to be performed outside of standard optical laboratories.

Introduction: While numerous publications have demonstrated the correlation of poor single-leg balance and core motor control with an increased risk of anterior cruciate ligament (ACL) injuries in skeletally mature female athletes, few have analysed the preadolescent population regarding when indeed comparative deficits in balance and core control actually occur. The purpose of this study was to assess whether the neuromotor factors that place mature females at increased risk of ACL injury actually are present in preadolescents and if so when., Methods: This study used simplified modifications of classic drop-jump testing as well as single-leg balance tests performed on stable and unstable surfaces to assess balance and core motor control. 84 children (males and females) ranging in age from 6 to 13 years were divided into 4 equally sized groups based on their academic classes. Each group was compared with each other, and compared with a cohort of 205 collegiate athletes. The latter served as a comparative norm of mature athletes who had performed the same or similar testing., Results: Outcomes revealed that the preadolescent population performed poorly on the tests when compared with the collegiate population but the children matured with age until the eldest subgroups compared more favourably with the college-aged athletes. Girls appear to mature at a slightly earlier pace than boys. This study focusing on preadolescent children concluded that the neuromuscular changes that place females at greater risk of injury do not appear to occur prior to adolescence., Conclusions: Based on the outcomes of this study, it is suggested that sex differences regarding balance and core control deficits that can increase risk of ACL injuries likely occur after grade school (age 12-13).

Strong epidemiological data indicate that chemotherapy-induced gut toxicity and pain occur in parallel, indicating common underlying mechanisms. We have recently outlined evidence suggesting that TLR4 signaling may contribute to both side effects. We therefore aimed to determine if genetic deletion of TLR4 improves chemotherapy-induced gut toxicity and pain. Forty-two female wild-type (WT) and 42 Tlr4 null (-/-) BALB/c mice weighing between 18 and 25 g (10-13 weeks) received a single 270 mg/kg (i.p.) dose of irinotecan hydrochloride or vehicle control and were killed at 6, 24, 48, 72, and 96 hours. Bacterial sequencing was conducted on cecal samples of control animals to determine the gut microbiome profile. Gut toxicity was assessed using validated clinical and histopathologic markers, permeability assays, and inflammatory markers. Chemotherapy-induced pain was assessed using the validated rodent facial grimace criteria, as well as immunologic markers of glial activation in the lumbar spinal cord. TLR4 deletion attenuated irinotecan-induced gut toxicity, with improvements in weight loss (P = 0.0003) and diarrhea (P < 0.0001). Crypt apoptosis was significantly decreased in BALB/c-Tlr4(-/-billy) mice (P < 0.0001), correlating with lower mucosal injury scores (P < 0.005). Intestinal permeability to FITC-dextran (4 kDa) and LPS translocation was greater in WT mice than in BALB/c-Tlr4(-/-billy) (P = 0.01 and P < 0.0001, respectively). GFAP staining in the lumbar spinal cord, indicative of astrocytic activation, was increased at 6 and 72 hours in WT mice compared with BALB/c-Tlr4(-/-billy) mice (P = 0.008, P = 0.01). These data indicate that TLR4 is uniquely positioned to mediate irinotecan-induced gut toxicity and pain, highlighting the possibility of a targetable gut/CNS axis for improved toxicity outcomes. Mol Cancer Ther; 15(6); 1376-86. ©2016 AACR., (©2016 American Association for Cancer Research.)

The detection of cytokines in body fluids, cells, tissues and organisms continues to attract considerable attention due to the importance of these key cell signaling molecules in biology and medicine. In this review, we describe recent advances in cytokine detection in the course of ongoing pursuit of new analytical approaches for these trace analytes with specific focus on immunosensing. We discuss recent elegant designs of sensing interface with improved performance with respect to sensitivity, selectivity, stability, simplicity, and the absence of sample matrix effects. Various immunosensing approaches based on multifunctional nanomaterials open novel opportunities for ultrasensitive detection of cytokines in body fluids in vitro and in vivo. Methodologies such as suspension arrays also known as bead assays together with optical fiber-based sensors, on their own or in combination with microfluidic devices will continue to have an important role to address the grand challenge of real-time in vivo multiplex cytokine detection., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Purpose: Chemotherapy-induced gut toxicity is associated with significant pain, and pain influences gut function. Toll-like receptors (TLRs) that regulate gut homeostasis are activated by tissue damage and microbes, and their altered expression following chemotherapy may change cellular responses. This study examined the interaction between chemotherapy-induced gut toxicity and pain and related these to gut TLR and glial fibrillary acidic protein (GFAP) expression., Methods: Female tumor bearing Dark Agouti rats received irinotecan (175 mg/kg, n = 34) or vehicle (n = 5) and were assessed over 120 h for gut toxicity (diarrhea, weight loss), pain (facial), and GFAP, TLR2, 4, 5, and 9 gut expression., Results: Irinotecan caused diarrhea (72 % of animals grade ≥ 1), weight loss (11.1 ± 6.6 %, P < 0.0001), and pain (5 (0-5), P < 0.0001) all peaking at 72 h. Higher pain scores were observed in rats with diarrhea versus those without: median (range) of 2.0 (0-5) versus 0 (0-5), P = 0.01. Irinotecan also caused a decrease in TLR4 and 5, and an increase in GFAP expression in jejuna crypt at 96 and 120 h (all P < 0.05); with lower TLR4 expression associated with lower pain (P = 0.012)., Conclusions: The association between gut toxicity and pain suggests these toxicities are linked, possibly via TLR-mediated inflammatory pathways. Further, as TLR4 and 5 expression was absent during recovery in the jejuna and GFAP expression was increased in the jejuna, this implies expression of these may be critical in the healing phase following chemotherapy. Detailed studies of gut TLRs and GFAP are now warranted.

Background and Purpose: The toll-like receptor TLR4 is involved in neuropathic pain and in drug reward and reinforcement. The opioid inactive isomers (+)-naltrexone and (+)-naloxone act as TLR4 antagonists, reversing neuropathic pain and reducing opioid and cocaine reward and reinforcement. However, how these agents modulate TLR4 signalling is not clear. Here, we have elucidated the molecular mechanism of (+)-naltrexone and (+)-naloxone on TLR4 signalling., Experimental Approach: BV-2 mouse microglial cell line, primary rat microglia and primary rat peritoneal macrophages were treated with LPS and TLR4 signalling inhibitors. Effects were measured using Western blotting, luciferase reporter assays, fluorescence microscopy and ELISA KEY RESULTS: (+)-Naltrexone and (+)-naloxone were equi-potent inhibitors of the LPS-induced TLR4 downstream signalling and induction of the pro-inflammatory factors NO and TNF-α. Similarly, (+)-naltrexone or (+)-naloxone inhibited production of reactive oxygen species and increased microglial phagocytosis, induced by LPS. However, (+)-naltrexone and (+)-naloxone did not directly inhibit the increased production of IL-1β, induced by LPS. The drug interaction of (+)-naloxone and (+)-naltrexone was additive. (+)-Naltrexone or (+)-naloxone inhibited LPS-induced activation of IFN regulatory factor 3 and production of IFN-β. However, they did not inhibit TLR4 signalling via the activation of either NF-κB, p38 or JNK in these cellular models., Conclusions and Implications: (+)-Naltrexone and (+)-naloxone were TRIF-IFN regulatory factor 3 axis-biased TLR4 antagonists. They blocked TLR4 downstream signalling leading to NO, TNF-α and reactive oxygen species. This pattern may explain, at least in part, the in vivo therapeutic effects of (+)-naltrexone and (+)-naloxone., (© 2015 The British Pharmacological Society.)

Drug addiction and dependence have proven to be difficult psychiatric disorders to treat. The limited efficacy of neuronally acting medications, such as acamprosate and naltrexone, highlights the need to identify novel targets. Recent research has underscored the importance of the neuroimmune system in many behavioural manifestations of drug addiction. In this review, we propose that our appreciation for complex phenotypes such as drug addiction and dependence will come with a greater understanding that these disorders are the result of intricate, interconnected signalling pathways that are, if only partially, determined at the receptor level. The idea of receptor heteromerisation and receptor mosaics will be introduced to explain cross talk between the receptors and signalling molecules implicated in neuroimmune signalling pathways., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The initial reinforcing properties of drugs of abuse, such as cocaine, are largely attributed to their ability to activate the mesolimbic dopamine system. Resulting increases in extracellular dopamine in the nucleus accumbens (NAc) are traditionally thought to result from cocaine's ability to block dopamine transporters (DATs). Here we demonstrate that cocaine also interacts with the immunosurveillance receptor complex, Toll-like receptor 4 (TLR4), on microglial cells to initiate central innate immune signaling. Disruption of cocaine signaling at TLR4 suppresses cocaine-induced extracellular dopamine in the NAc, as well as cocaine conditioned place preference and cocaine self-administration. These results provide a novel understanding of the neurobiological mechanisms underlying cocaine reward/reinforcement that includes a critical role for central immune signaling, and offer a new target for medication development for cocaine abuse treatment.

An inflammatory response is instrumental in the physiological process of parturition but the upstream signals initiating inflammation are undefined. Because endogenous ligands for Toll-like receptor 4 (TLR4) are released in late gestation, we hypothesized that on-time labor requires TLR4 signaling, to trigger a cytokine and leukocyte response and accelerate the parturition cascade. In pregnant TLR4-deficient (Tlr4-/-) mice, average gestation length was extended by 13 hours and increased perinatal mortality was seen compared with wild-type controls. Quantification of cytokine and uterine activation gene expression showed that late gestation induction of Il1b, Il6, Il12b, and Tnf expression seen in control placenta and fetal membranes was disrupted in Tlr4-/- mice, and accompanied by a transient delay in expression of uterine activation genes, including prostaglandin F receptor, oxytocin receptor, and connexin-43. Leukocyte populations were altered before birth in TLR4-deficient females, with fewer neutrophils and macrophages in the placenta, and fewer dendritic cells and more regulatory T cells in the myometrium. Administration of TLR4 ligand lipopolysaccharide to pregnant wild-type mice induced cytokine expression and fetal loss, whereas Tlr4-/- pregnancies were protected. The small molecule TLR4 antagonist (+)-naloxone increased mean duration of gestation by 16 hours in wild-type mice. Collectively, these data demonstrate that TLR4 is a key upstream regulator of the inflammatory response acting to drive uterine activation and control the timing of labor. Because causal pathways for term and preterm labor converge with TLR4, interventions to manipulate TLR4 signaling may have therapeutic utility for women at risk of preterm labor, or in postterm pregnancy.

Background: Medication overuse headache (MOH) is a condition bordering between a chronic pain condition and a substance dependence disorder. Activation of immunocompetent glial cells in the central nervous system has been linked to both pathological pain and drug addiction/reward. Preclinically, ibudilast attenuates glial activation and is able to reduce neuropathic pain and markers of substance dependence. We therefore hypothesized ibudilast would reduce headache burden and opioid analgesic requirements in patients with opioid overuse headache., Objective: To determine if treatment with ibudilast provides a greater reduction in headache index than placebo in MOH patients consuming opioids., Methods: Participants with MOH who were using opioids were randomized via computer-generated code to ibudilast 40 mg or placebo twice daily for 8 weeks in a double-blind, parallel groups study. Before randomization participants completed a 4-week baseline headache diary. During treatment, headache diary data collection continued and participants attended 4 study visits during which quantitative sensory testing was performed. Blood samples for immune biomarker analyses were collected before and after treatment in a subgroup of participants., Results: Thirty-four participants were randomized, 13 of 15 randomized to ibudilast and 17 of 19 randomized to placebo completed treatment. Ibudilast was generally well-tolerated with mild, transient nausea reported as the most common adverse event (66.7% vs 10.5% in placebo group). Results are shown as mean (SD). At the end of treatment no differences in the primary outcome average daily headache index (placebo 62 [44] vs ibudilast 77 [72] groups, difference -15, CI -65 to 35 h × numerical rating scale), or secondary outcomes headache frequency (placebo 23 [8.1] vs ibudilast 24.5 [6.2], difference -1.5, CI -7.7 to 4.8 days/month) and opioid intake (placebo 20.6 [43] vs ibudilast 19 [24.3], difference 1.6, CI -31.5 to 34.8 mg morphine equivalent) were observed between placebo and ibudilast groups., Conclusions: Using the current dosing regimen, ibudilast does not improve headache or reduce opioid use in patients with MOH without mandated opioid withdrawal. However, it would be of interest to determine in future trials if ibudilast is able to improve ease of withdrawal during a forced opioid down-titration when incorporated into an MOH detoxification program., (© 2015 American Headache Society.)

Context: Patellar tendinopathy is a common condition. There are a wide variety of treatment options available, the majority of which are nonoperative. No consensus exists on the optimal method of treatment., Evidence Acquisition: PubMed spanning 1962-2014., Study Design: Clinical review., Level of Evidence: Level 4., Results: The majority of cases resolve with nonoperative therapy: rest, physical therapy with eccentric exercises, cryotherapy, anti-inflammatories, corticosteroid injections, extracorporeal shockwave therapy, glyceryl trinitrate, platelet-rich plasma injections, and ultrasound-guided sclerosis. Refractory cases may require either open or arthroscopic debridement of the patellar tendon. Corticosteroid injections provide short-term pain relief but increase risk of tendon rupture. Anti-inflammatories and injectable agents have shown mixed results. Surgical treatment is effective in many refractory cases unresponsive to nonoperative modalities., Conclusion: Physical therapy with an eccentric exercise program is the mainstay of treatment for patellar tendinopathy. Platelet-rich plasma has demonstrated mixed results; evidence-based recommendations on its efficacy cannot be made. In the event that nonoperative treatment fails, surgical intervention has produced good to excellent outcomes in the majority of patients., (© 2015 The Author(s).)

Background: Surgical intervention for partial and full-thickness gluteus medius tears is often recommended for patients who have persistent pain despite nonoperative treatment. Traditionally, the surgical intervention has been carried out through open techniques with good results; however, advantages of endoscopic techniques include less tissue dissection, improved tendon mobilization, and the benefit of arthroscopic correction of intra-articular pathological conditions. The purpose of this report is to provide an update on a previously published study of patients with a gluteus medius tear, with inclusion of additional patients followed for a minimum of two years., Methods: The study included thirty-four patients who had undergone an endoscopic gluteus medius repair with correction of intra-articular pathological conditions between April 2009 and April 2012 and had been followed for a minimum of two years. Patient-reported outcome measures included the modified Harris hip score, Nonarthritic Hip Score, and Hip Outcome Score-Activities of Daily Living and Sport-Specific Subscale. A visual analog scale (VAS) pain score and a patient satisfaction score were also recorded., Results: The cohort consisted of two men and thirty-two women with a mean age of fifty-seven years (range, twenty to seventy-nine years). Ten patients had a full-thickness tear, and twenty-four patients had a partial-thickness tear. Seventeen patients were treated with a suture bridge technique, after completion of the tear if it was not already complete, and seventeen patients were treated with the transtendinous technique. All patients had surgical correction of intra-articular pathological conditions. There was a significant improvement in all four patient-reported outcomes at three specified time-points. The mean VAS pain score decreased from 6.6 preoperatively to 2.4 at the time of the two-year follow-up (p < 0.001). The mean satisfaction score was 8.5 at two years postoperatively. Of twenty-six patients who had a gait deviation preoperatively, fifteen (58%) regained a completely normal gait. There was no significant difference in patient-reported outcome measures between the two surgical techniques. Four patients required total hip replacement at eleven to sixteen months postoperatively., Conclusions: After a minimum of two years of follow-up, endoscopic surgical repair with correction of intra-articular pathological conditions was found to be an effective treatment for patients with a gluteus medius tear., (Copyright © 2015 by The Journal of Bone and Joint Surgery, Incorporated.)

Purpose: To determine whether reaming of anterior cruciate ligament (ACL) reconstruction tibial tunnels with a 10-mm-diameter reamer would result in injury to the anterior roots of the medial and lateral menisci in an in vitro model when using a tibial aiming device at two settings (40° and 60°)., Methods: Three-dimensional footprints of the ACL and the anterior roots of the menisci were measured for 12 human cadaveric tibias. Measurements were taken before and after attempted reaming of an ACL tibial reconstruction tunnel in the calculated ACL centre using a tibial aiming device set at two angles (40° and 60°)., Results: Iatrogenic injury to the anterior root of the medial meniscus caused by overlap with the reamed tibial tunnel was found in 3/6 specimens in Group 1 (40°) and 0/6 specimens in Group 2 (60°). The average area of iatrogenic injury in Group 1 was 9.6 mm(2) (8.6 % of the root). There was iatrogenic injury to the anterior root of the lateral meniscus in 4/6 specimens for both groups. The average area of iatrogenic injury was 20.5 mm(2) (28.8 %) for Group 1 and 16.2 mm(2) (25.9 %) for Group 2., Conclusions: Reaming of ACL tibial reconstruction tunnels carries a risk of iatrogenic injury to the anterior meniscus roots, even when tunnels are reamed based on guide pin placement in the calculated centre of the ACL. Reaming at varying tibial aiming device angle settings can affect the obliquity of the tunnel aperture and cause iatrogenic injury to the anterior meniscal roots. Caution should be exercised clinically to avoid iatrogenic injury to both the anterior meniscal roots while reaming tibial tunnels during ACL reconstructions.

Aims: Ketamine analgesia is limited by low intrinsic efficacy compounded by large interindividual variability in drug responses, possibly due to the heterogeneity in drug concentration. The CYP2B6*6 allele is associated with substantially reduced ketamine metabolism in vitro and, therefore, may affect ketamine clearance. Our aims were to examine the impact of the CYP2B6*6 allele on ketamine plasma clearance and on adverse effects in chronic pain patients., Methods: CYP2B6 genotypes were identified in 49 chronic pain patients who received 24 h continuous subcutaneous infusions of ketamine. Steady-state plasma concentrations of ketamine (Css,k ) and norketamine (Css,nk ) were determined using HPLC., Results: The median plasma clearance of ketamine after 100 mg 24 h(-1) dose was significantly lower in patients with the CYP2B6*6/*6 (21.6 l h(-1) ) and CYP2B6*1/*6 (40.6 l h(-1) ) genotypes compared with patients with the CYP2B6*1/*1 genotype (68.1 l h(-1) , P < 0.001). The ketamine : norketamine plasma metabolic ratio was significantly higher in patients with the CYP2B6*6/*6 genotype than in those with the CYP2B6*1/*6 and the CYP2B6*1/*1 genotypes (P < 0.001). Patients who experienced adverse effects had lower plasma clearance (45.6 l h(-1) ) than those who did not (52.6 l h(-1) , P = 0.04). The CYP2B6*6 genotype and age, and their combined impact explained 40%, 30% and 60% of the variation in Css,k , respectively. Similar results were observed after higher doses., Conclusions: The CYP2B6*6 allele is associated with a substantial decrease in steady-state ketamine plasma clearance in chronic pain patients. The decreased clearance and resultant higher plasma concentrations may be associated with a higher incidence of ketamine adverse effects., (© 2015 The British Pharmacological Society.)

Background: To report a case series of failures of bioabsorbable interference screws with possible identification of a novel failure mechanism., Methods: A retrospective review of ACL reconstructions by the senior author utilizing BioComposite™ Interference Screws (Arthrex, Inc., Naples, FL) was performed. Complications related to screw placement, including fracture, breakage or bending were examined. Our rate and methods of failure were compared to those quoted in the current literature., Results: Eighty-seven patients of average age 23.8 years met inclusion criteria. There were eight screw failures in six patients, with femoral failure in seven and tibial failure in one. The femoral screw fractured halfway between the tip and head in five, while the head of the screw broke in one and the screw bent in another. In the case of tibial interference screw fracture, failure occurred halfway between the tip and head. The insertion device that was used was replaced after recognition of material deformation and considered a potential contributor to the breakage risk as no further screw failures have occurred since., Conclusions: We demonstrate a unique failure mechanism of bio-absorbable interference screws. In each case, the reconstruction was salvaged. Regular inspection of materials and implants can ensure optimal outcomes and decrease complications intra-operatively., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Lactation mastitis is a common, but poorly understood, inflammatory breast disease that is a significant health burden. A better understanding of the aetiology of mastitis is urgently required, and will assist in the development of improved prevention and treatment strategies in both human and animal species. Studies in mice have the potential to greatly assist in identifying new drug candidates for clinical trials, and in developing a better understanding of the disease. Mouse models of mastitis involve administration of a mastitis-inducing agent to the mammary gland usually during lactation to examine the host immune response, and progression through to resolution of the disease. There are important variations in the protocols of these mouse models that critically affect the conclusions that can be drawn from the research. Some protocols involve weaning of offspring at the time of mastitis induction, and there are variations in the mastitis-inducing agent and its carrier. Induction of mammary gland involution through weaning of offspring limits the capacity to study the disease in the context of a lactating mammary gland. Administration of live bacteria in an aqueous carrier can cause sepsis, restricting the physiological relevance of the model. Mouse model research should employ appropriately designed controls and closely monitor the health of the mice. In this commentary, we discuss the advantages and study design limitations of each mouse model, and highlight the potential for further development of physiologically relevant mouse models of mastitis.

Increasing evidence demonstrates induction of proinflammatory Toll-like receptor (TLR) 2 and TLR4 signaling by morphine and, TLR4 signaling by alcohol; thus indicating a common site of drug action and a potential novel innate immune-dependent hypothesis for opioid and alcohol drug interactions. Hence, the current study aimed to assess the role of TLR2, TLR4, MyD88 (as a critical TLR-signaling participant), NF-κB, Interleukin-1β (IL-1β; as a downstream proinflammatory effector molecule) and the μ opioid receptor (MOR; as a classical site for morphine action) in acute alcohol-induced sedation (4.5g/kg) and alcohol (2.5g/kg) interaction with morphine (5mg/kg) by assessing the loss of righting reflex (LORR) as a measure of sedation. Wild-type male Balb/c mice and matched genetically-deficient TLR2, TLR4, and MyD88 strains were utilized, together with pharmacological manipulation of MOR, NF-κB, TLR4 and Interleukin-1β. Alcohol induced significant LORR in wild-type mice; this was halved by MyD88 and TLR4 deficiency, and surprisingly nearly completely eliminated by TLR2 deficiency. In contrast, the interaction between morphine and alcohol was found to be MOR-, NF-κB-, TLR2- and MyD88-dependent, but did not involve TLR4 or Interleukin-1β. Morphine-alcohol interactions caused acute elevations in microglial cell counts and NF-κB-p65 positive cells in the motor cortex in concordance with wild-type and TLR2 deficient mouse behavioral data, implicating neuroimmunopharmacological signaling as a pivotal mechanism in this clinically problematic drug-drug interaction., (Copyright © 2014 Elsevier Inc. All rights reserved.)

We have recently shown that several classes of glucuronide metabolites, including the morphine metabolite morphine-3-glucuronide and the ethanol metabolite ethyl glucuronide, cause toll like receptor 4 (TLR4)-dependent signaling in vitro and enhanced pain in vivo. Steroid hormones, including estrogens and corticosterone, are also metabolized through glucuronidation. Here we demonstrate that in silico docking predicts that corticosterone, corticosterone-21-glucuronide, estradiol, estradiol-3-glucuronide and estradiol-17-glucuronide all dock with the MD-2 component of the TLR4 receptor complex. In addition to each docking with MD-2, the docking of each was altered by pre-docking with (+)-naloxone, a TLR4 signaling inhibitor. As agonist versus antagonist activity cannot be determined from these in silico interactions, an in vitro study was undertaken to clarify which of these compounds can act in an agonist fashion. Studies using a cell line transfected with TLR4, necessary co-signaling molecules, and a reporter gene revealed that only estradiol-3-glucuronide and estradiol-17-glucuronide increased reporter gene product, indicative of TLR4 agonism. Finally, in in vivo studies, each of the 5 drugs was injected intrathecally at equimolar doses. In keeping with the in vitro results, only estradiol-3-glucuronide and estradiol-17-glucuronide caused enhanced pain. For both compounds, pain enhancement was blocked by the TLR4 antagonist lipopolysaccharide from Rhodobacter sphaeroides, evidence for the involvement in TLR4 in the resultant pain enhancement. These findings have implications for several chronic pain conditions, including migraine and temporomandibular joint disorder, in which pain episodes are more likely in cycling females when estradiol is decreasing and estradiol metabolites are at their highest., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background: There has been an increase in minimally invasive surgery for chronic exertional compartment syndrome (CECS), despite the potential for incomplete compartment release and iatrogenic injuries. To our knowledge, no study has examined the effect of the length of fascial release on compartment pressures., Purpose/hypothesis: The purpose was to explain the high failure rate seen in fascial release for CECS by evaluating the effect of fasciotomy length on intracompartmental pressures. We hypothesized that complete fascial release would need to be performed to return pressures to baseline levels., Study Design: Controlled laboratory study., Methods: Five male swine (10 lower extremities) were anesthetized. A slit catheter, connected to a pressure monitor, was inserted into the anterior compartment and a solution containing 5% swine albumin was injected into the compartment until the compartment pressure was >25 mm Hg for 10 minutes. Pressures were measured at rest, after the injection, and after each 10% incremental fasciotomy release., Results: The mean resting intracompartmental pressure was 3.2 mm Hg (range, 0-6 mm Hg), which increased after the injection to a mean of 37 mm Hg (range, 26-67 mm Hg). After complete fasciotomy, the mean pressure was 1.1 mm Hg (range, 0-4 mm Hg). There was a strong negative correlation (r=-0.693) between fasciotomy length and intracompartmental pressure. In 90% of the specimens, the pressures were <15 mm Hg after 80% fascial release, and after 90% release, all pressures were ≤8 mm Hg., Conclusion: This study demonstrates a strong correlation between fasciotomy length and a reduction in intracompartmental pressures in a swine model. Our study suggests that 90% fascial release may represent a possible watershed zone, returning the intracompartmental pressure to a value at or near baseline values., Clinical Relevance: The results suggest that even in cases with near complete fascial release, intracompartmental pressures may decrease enough to provide symptomatic relief and avoid possible iatrogenic injuries associated with percutaneous release. It is unknown whether the swine model may adequately translate to the clinical setting; thus, recommendations should be taken with caution, and future studies should be performed to examine the correlation in a human model., (© 2014 The Author(s).)

There is growing recognition that glial proinflammatory activation importantly contributes to the rewarding and reinforcing effects of a variety of drugs of abuse, including cocaine, methamphetamine, opioids, and alcohol. It has recently been proposed that glia are recognizing, and becoming activated by, such drugs as a CNS immunological response to these agents being xenobiotics; that is, substances foreign to the brain. Activation of glia, primarily microglia, by various drugs of abuse occurs via toll like receptor 4 (TLR4). The detection of such xenobiotics by TLR4 results in the release of glial neuroexcitatory and neurotoxic substances. These glial products of TLR4 activation enhance neuronal excitability within brain reward circuitry, thereby enhancing their rewarding and reinforcing effects. Indeed, selective pharmacological blockade of TLR4 activation, such as with the non-opioid TLR4 antagonist (+)-naltrexone, suppresses a number of indices of drug reward/reinforcement. These include: conditioned place preference, self-administration, drugprimed reinstatement, incubation of craving, and elevations of nucleus accumbens shell dopamine. Notably, TLR4 blockade fails to alter self-administration of food, indicative of a selective effect on drugs of abuse. Genetic disruption of TLR4 signaling recapitulates the effects of pharmacological TLR4 blockade, providing converging lines of evidence of a central importance of TLR4. Taken together, multiple lines of evidence converge to raise TLR4 as a promising therapeutic target for drug abuse.

Background: There is a lack of consensus regarding the optimal surgical approach and fixation method for distal biceps tendon ruptures. The purpose of this study was to conduct a systematic review comparing the results of the various surgical approaches and repair techniques for acute distal biceps tendon ruptures., Methods: We searched the MEDLINE, Cochrane, and Embase databases for all published randomized controlled trials, prospective cohort studies, or case series that involved primary repairs of acute distal biceps tendon ruptures with use of a cortical button, intraosseous screws, suture anchors, or bone tunnels for fixation. Exclusion criteria included case reports, cadaveric studies, repairs of partial ruptures, revision repairs, and multiple methods of fixation in the same patient. Statistical analysis was performed with use of the chi-square test., Results: Twenty-two studies met the inclusion criteria. The total number of patients was 494 (498 elbows). The complication rate was 24.5% (122 of 498 elbows) overall, and it was 23.9% (seventy-eight of 327) for one-incision procedures and 25.7% (forty-four of 171) for two-incision procedures (p = 0.32). The complication rate was 26.4% (seventy-five of 284) for suture anchors, 20.4% (thirty-four of 167) for bone tunnels, 44.8% (thirteen of twenty-nine) for intraosseous screws, and 0% (zero of eighteen) for cortical button fixation. The complication rate for use of bone tunnels was significantly lower than that for intraosseous screws (p < 0.01). Similarly, the cortical button method proved superior to intraosseous screws (p = 0.01). The most common complication was lateral antebrachial cutaneous nerve neurapraxia (9.6% across all studies, 11.6% for one incision, and 5.8% for two incisions)., Conclusions: The complication rate did not differ significantly between one and two-incision distal biceps repairs; however, the bone tunnel and cortical button methods had significantly lower complication rates compared with suture anchors and intraosseous screws. Further studies are needed to determine the optimal number of incisions., (Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.)

Chronic morphine therapy has been associated with paradoxically increased pain. Codeine is a widely used opioid, which is metabolized to morphine to elicit analgesia. Prolonged morphine exposure exacerbates pain by activating the innate immune toll-like receptor-4 (TLR4) in the central nervous system. In silico docking simulations indicate codeine also docks to MD2, an accessory protein for TLR4, suggesting potential to induce TLR4-dependent pain facilitation. We hypothesized codeine would cause TLR4-dependent hyperalgesia/allodynia that is disparate from its opioid receptor-dependent analgesic rank potency. Hyperalgesia and allodynia were assessed using hotplate and von Frey tests at days 0, 3 and 5 in mice receiving intraperitoneal equimolar codeine (21 mg kg(-1)), morphine (20 mg kg(-1)) or saline, twice daily. This experiment was repeated in animals with prior partial nerve injury and in TLR4 null mutant mice. Interventions with interleukin-1 receptor antagonist (IL-1RA) and glial-attenuating drug ibudilast were assessed. Analyses of glial activation markers (glial fibrillary acid protein and CD11b) in neuronal tissue were conducted at the completion of behavioural testing. Despite providing less acute analgesia (P=0.006), codeine induced similar hotplate hyperalgesia to equimolar morphine vs saline (-9.5 s, P<0.01 and -7.3 s, P<0.01, respectively), suggesting codeine does not rely upon conversion to morphine to increase pain sensitivity. This highlights the potential non-opioid receptor-dependent nature of codeine-enhanced pain sensitivity-although the involvement of other codeine metabolites cannot be ruled out. IL-1RA reversed codeine-induced hyperalgesia (P<0.001) and allodynia (P<0.001), and TLR4 knock-out protected against codeine-induced changes in pain sensitivity. Glial attenuation with ibudilast reversed codeine-induced allodynia (P<0.001), and thus could be investigated further as potential treatment for codeine-induced pain enhancement.

CNS immune signaling contributes to deleterious opioid effects including hyperalgesia, tolerance, reward, and dependence/withdrawal. Such effects are mediated by opioid signaling at toll-like receptor 4 (TLR4), presumptively of glial origin. Whether CNS endothelial cells express TLR4 is controversial. If so, they would be well positioned for activation by blood-borne opioids, contributing to opioid-induced pro-inflammatory responses. These studies examined adult primary rat CNS endothelial cell responses to (-)-morphine or its mu opioid receptor (MOR)-inactive metabolite morphine-3-glucuronide (M3G), both known TLR4 agonists. We demonstrate that adult rat CNS endothelial cells express functional TLR4. M3G activated nuclear factor kappaB (NF-κB), increased tumor necrosis factor-α (TNFα) and cyclooxygenase-2 (COX2) mRNAs, and released prostaglandin E2 (PGE2) from these cells. (-)-Morphine-induced upregulation of TNFα mRNA and PGE2 release were unmasked by pre-treatment with nalmefene, a MOR antagonist without TLR4 activity (unlike CTAP, shown to have both MOR- and TLR4-activity), suggestive of an interplay between MOR and TLR4 co-activation by (-)-morphine. In support, MOR-dependent Protein Kinase A (PKA) opposed TLR4 signaling, as PKA inhibition (H-89) also unmasked (-)-morphine-induced TNFα and COX2 mRNA upregulation. Intrathecal injection of CNS endothelial cells, stimulated in vitro with M3G, produced TLR4-dependent tactile allodynia. Further, cortical suffusion with M3G in vivo induced TLR4-dependent vasodilation. Finally, endothelial cell TLR4 activation by lipopolysaccharide and/or M3G was blocked by the glial inhibitors AV1013 and propentofylline, demonstrating endothelial cells as a new target of such drugs. These data indicate that (-)-morphine and M3G can activate CNS endothelial cells via TLR4, inducing proinflammatory, biochemical, morphological, and behavioral sequelae. CNS endothelial cells may have previously unanticipated roles in opioid-induced effects, in phenomena blocked by presumptive glial inhibitors, as well as TLR4-mediated phenomena more broadly., (Copyright © 2014 IBRO. All rights reserved.)

Background: There is a paucity of articles in the surgical literature demonstrating transfer validity (transfer of training). The purpose of this study was to assess whether skills learned on the ArthroSim virtual-reality arthroscopic knee simulator transferred to greater skill levels in the operating room., Methods: Postgraduate year-3 orthopaedic residents were randomized into simulator-trained and control groups at seven academic institutions. The experimental group trained on the simulator, performing a knee diagnostic arthroscopy procedure to a predetermined proficiency level based on the average proficiency of five community-based orthopaedic surgeons performing the same procedure on the simulator. The residents in the control group continued their institution-specific orthopaedic education and training. Both groups then performed a diagnostic knee arthroscopy procedure on a live patient. Video recordings of the arthroscopic surgery were analyzed by five pairs of expert arthroscopic surgeons blinded to the identity of the residents. A proprietary global rating scale and a procedural checklist, which included visualization and probing scales, were used for rating., Results: Forty-eight (89%) of the fifty-four postgraduate year-3 residents from seven academic institutions completed the study. The simulator-trained group averaged eleven hours of training on the simulator to reach proficiency. The simulator-trained group performed significantly better when rated according to our procedural checklist (p = 0.031), including probing skills (p = 0.016) but not visualization skills (p = 0.34), compared with the control group. The procedural checklist weighted probing skills double the weight of visualization skills. The global rating scale failed to reach significance (p = 0.061) because of one extreme outlier. The duration of the procedure was not significant. This lack of a significant difference seemed to be related to the fact that residents in the control group were less thorough, which shortened their time to completion of the arthroscopic procedure., Conclusions: We have demonstrated transfer validity (transfer of training) that residents trained to proficiency on a high-fidelity realistic virtual-reality arthroscopic knee simulator showed a greater skill level in the operating room compared with the control group., Clinical Relevance: We believe that the results of our study will stimulate residency program directors to incorporate surgical simulation into the core curriculum of their residency programs., (Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.)

: While the preparticipation physical evaluation (PPE) is widely accepted, its usage and content are not standardized. Implementation is affected by cost, access, level of participation, participant age/sex, and local/regional/national mandate. Preparticipation physical evaluation screening costs are generally borne by the athlete, family, or club. Screening involves generally agreed-upon questions based on expert opinion and tested over decades of use. No large-scale prospective controlled tracking programs have examined PPE outcomes. While the panel did not reach consensus on electrocardiogram (ECG) screening as a routine part of PPE, all agreed that a history and physical exam focusing on cardiac risk is essential, and an ECG should be used where risk is increased. The many areas of consensus should help the American College of Sports Medicine and Fédération Internationale du Médicine du Sport in developing a universally accepted PPE. An electronic PPE, using human-centered design, would be comprehensive, would provide a database given that PPE is mandatory in many locations, would simplify PPE administration, would allow remote access to clinical data, and would provide the much-needed data for prospective studies in this area.

While the preparticipation physical evaluation (PPE) is widely accepted, its usage and content are not standardized. Implementation is affected by cost, access, level of participation, participant age/sex, and local/regional/national mandate. PPE screening costs are generally borne by the athlete, family, or club. Screening involves generally agreed-upon questions based on expert opinion and tested over decades of use. No large-scale prospective controlled tracking programs have examined PPE outcomes. While the panel did not reach consensus on electrocardiogram screening as a routine part of PPE, all agreed that a history and physical exam focusing on cardiac risk is essential, and an ECG should be used where risk is increased. The many areas of consensus should help the American College of Sports Medicine and the Fédération Internationale du Médicine du Sport in developing a universally accepted PPE. An electronic PPE, using human-centered design, would be comprehensive, would provide a database given that PPE is mandatory in many locations, would simplify PPE administration, would allow remote access to clinical data, and would provide the much-needed data for prospective studies in this area.

Opioids activate glia in the central nervous system in part by activating the toll-like receptor 4 (TLR4)/myeloid differentiation 2 (MD2) complex. TLR4/MD2-mediated activation of glia by opioids compromises their analgesic actions. Glial activation is also hypothesized as pivotal in opioid-mediated reward and tolerance and as a contributor to opioid-mediated respiratory depression. We tested the contribution of TLR4 to opioid-induced respiratory depression using rhythmically active medullary slices that contain the pre-Bötzinger Complex (preBötC, an important site of respiratory rhythm generation) and adult rats in vivo. Injection with DAMGO (μ-opioid receptor agonist; 50 μM) or bath application of DAMGO (500 nM) or fentanyl (1 μM) slowed frequency recorded from XII nerves to 40%, 40%, or 50% of control, respectively. This DAMGO-mediated frequency inhibition was unaffected by preapplication of lipopolysaccharides from Rhodobacter sphaeroides (a TLR4 antagonist, 2,000 ng/ml) or (+)naloxone (1-10 μM, a TLR4-antagonist). Bath application of (-)naloxone (500 nM; a TLR4 and μ-opioid antagonist), however, rapidly reversed the opioid-mediated frequency decrease. We also compared the opioid-induced respiratory depression in slices in vitro in the absence and presence of bath-applied minocycline (an inhibitor of microglial activation) and in slices prepared from mice injected (ip) 18 h earlier with minocycline or saline. Minocycline had no effect on respiratory depression in vitro. Finally, the respiratory depression evoked in anesthetized rats by tail vein infusion of fentanyl was unaffected by subsequent injection of (+)naloxone, but completely reversed by (-)naloxone. These data indicate that neither activation of microglia in preBötC nor TLR4/MD2-activation contribute to opioid-induced respiratory depression.

Background: Ulnar collateral ligament (UCL) reconstruction of the elbow has become increasingly more frequent among elite overhead athletes. The purpose of this study was to conduct a systematic review comparing the clinical outcomes and biomechanical results of the Jobe, modified Jobe, docking, modified docking, Endobutton, and interference screw techniques for UCL reconstruction., Hypothesis: The docking technique will have significantly fewer complications and improved return-to-play rate., Study Design: Systematic review; Level of evidence, 4., Methods: Using the Medline PubMed, Cochrane, and EMBASE databases, a search was performed of all published articles, including randomized controlled trials, cohort studies, and case series, examining UCL reconstructions performed using one of the above noted techniques and excluding case reports and hybrid techniques. Statistical analysis was performed using a χ(2) test of independence and 2-proportion Z test., Results: A total of 21 studies, 7 biomechanical and 14 clinical, met the inclusion criteria. There were 1368 patients. The overall complication rate was 18.6% (255/1368), further subdivided into 21 for the Jobe technique (29.2%), 203 for the modified Jobe technique (19.1%), 2 for the interference screw technique (10.0%), 2 (4.3%) for the modified docking technique, and 10 for the docking technique (6.0%). The most common complication across all studies was ulnar nerve neurapraxia in 176 patients (12.9%). The overall rate of return to play was 78.9%., Conclusion: Ulnar collateral ligament reconstruction utilizing the docking technique results in a significantly higher rate of return to play and a lower complication rate when compared with the Jobe and modified Jobe techniques., Clinical Relevance: A lower complication rate can lead to increased rates of return to play and better outcomes postoperatively., (© 2013 The Author(s).)

Major depressive disorder (MDD) poses one of the highest disease burdens worldwide. Yet, current treatments targeting serotonergic and noradrenaline reuptake systems are insufficient to provide long-term relief from depressive symptoms in most patients, indicating the need for new treatment targets. Having the ability to influence behavior similar to depressive symptoms, as well as communicate with neuronal and neuroendocrine systems, the innate immune system is a strong candidate for MDD treatments. Given the complex nature of immune signaling, the main question becomes: What is the role of the innate immune system in MDD? The current review presents evidence that toll-like receptor 4 (TLR4), via driving both peripheral and central immune responses, can interact with serotonergic neurotransmission and cause neuroendocrine disturbances, thus integrating with widely observed hallmarks of MDD. Additionally, through describing the multi-directional communication between immune, neural and endocrine systems in stress, TLR4-related mechanisms can mediate stress-induced adaptations, which are necessary for the development of MDD. Therefore, apart from exogenous pathogenic mechanisms, TLR4 is involved in immune changes as a result of endogenous stress signals, playing an integral part in the pathophysiology, and could be a potential target for pharmacological treatments to improve current interventions for MDD.

Background: Microglial activation is a prominent feature throughout the optic pathway in experimental glaucoma. Pro-inflammatory microglial activation may contribute to neurodegeneration through the release of pro-inflammatory cytokines and other inflammatory mediators. Systemic administration of lipopolysaccharide stimulates microglia to produce pro-inflammatory cytokines and chemoattractants. A preliminary investigation demonstrated pro-inflammatory microglial activation throughout the optic pathway following systemic lipopolysaccharide challenge. The aim of the current work was to investigate whether microglial priming with lipopolysaccharide would exacerbate optic nerve injury in rats following experimental glaucoma., Methods: Adult female Sprague-Dawley rats were divided into lipopolysaccharide treatment (n = 15) and saline treatment groups (n = 15). Microglial priming was induced with a 2.5-mg/kg intraperitoneal injection of lipopolysaccharide; control animals received saline. Experimental glaucoma was induced 48 h later in the right eyes of animals by laser photocoagulation of the trabecular meshwork. Animals were sacrificed 9 days after laser treatment., Results: The estimated number of axons per optic nerve was 51 327 ± 3868 (mean ± standard error of the mean) in the lipopolysaccharide group and 54 569 ± 6687 (mean ± standard error of the mean) in the saline group. Optic nerve axon counts were not significantly different between lipopolysaccharide and saline groups (P = 0.67)., Conclusions: Systemic lipopolysaccharide challenge had no discernible effect on optic nerve injury in laser-induced experimental glaucoma. These findings do not support the hypothesis that this model of experimental glaucoma involves inflammation and instead suggest that microglial activation may occur secondary to chronic neurodegeneration., (© 2013 Royal Australian and New Zealand College of Ophthalmologists.)

Mastitis is a common inflammatory disease during lactation that causes reduced milk supply. A growing body of evidence challenges the central role of pathogenic bacteria in mastitis, with disease severity associated with markers of inflammation rather than infection. Inflammation in the mammary gland may be triggered by microbe-associated molecular patterns (MAMPs) as well as danger-associated molecular patterns (DAMPs) binding to pattern recognition receptors such as the toll-like receptors (TLRs) on the surface of mammary epithelial cells and local immune cell populations. Activation of the TLR4 signalling pathway and downstream nuclear factor kappa B (NFkB) is critical to mediating local mammary gland inflammation and systemic immune responses in mouse models of mastitis. However, activation of NFkB also induces epithelial cell apoptosis and reduced milk protein synthesis, suggesting that inflammatory mediators activated during mastitis promote partial involution. Perturbed milk flow, maternal stress and genetic predisposition are significant risk factors for mastitis, and could lead to a heightened TLR4-mediated inflammatory response, resulting in increased susceptibility and severity of mastitis disease in the context of low MAMP abundance. Therefore, heightened host inflammatory signalling may act in concert with pathogenic or commensal bacterial species to cause both the inflammation associated with mastitis and lactation insufficiency. Here, we present an alternate paradigm to the widely held notion that breast inflammation is driven principally by infectious bacterial pathogens, and suggest there may be other therapeutic strategies, apart from the currently utilised antimicrobial agents, that could be employed to prevent and treat mastitis in women.

Examination of the patellofemoral joint can prove to be challenging. Although certain acute injuries such as patella fracture or tendon rupture can be diagnosed quickly, more chronic injuries such as patellar subluxation and patellofemoral pain syndrome are more difficult to diagnose because of the subtlety of the examination findings. The source of the problem can also vary, and must be identified to direct treatment. Adding to the complexity is that other structures around the knee may present with anterior knee pain and can be mistaken for patellofemoral disorder, which is why the patellofemoral examination should be performed in the context of a complete knee examination. For all of these reasons, performing a thorough and systematic examination of the patellofemoral joint can lead to optimal outcomes for patients., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Lactation mastitis is a debilitating inflammatory breast disease in postpartum women. Disease severity is associated with markers of inflammation rather than bacterial load, suggesting that immune-signaling pathways activated in the host are important in the disease pathology. The role of the innate pattern recognition receptor toll-like receptor 4 (TLR4) in progression and resolution of mastitislike disease was investigated in a mouse model. Lipopolysaccharide in Matrigel (10 μg/10 μl) was administered into the teat canal of lactating Tlr4 null mutant and wild-type mice to induce a localized area of inflammation. Mastitis induction resulted in a marked influx of RB6-positive neutrophils and F4/80-positive macrophages, which was higher in Tlr4(-/-) mice compared to wild-type mice. Tlr4 null mutation resulted in an altered immune-signaling fingerprint following induction of mastitis, with attenuated serum cytokines, including CXCL1, CCL2, interleukin 1 beta, and tumor necrosis factor alpha compared to wild-type mice. In both genotypes, the localized area of inflammation had resolved after 7 days, and milk protein was evident. However, the mammary glands of wild-type mice exhibited reduced capacity for milk production, with decreased percent area populated with glandular epithelium and decreased abundance of nuclear phosphorylated signal transducer and activator of transcription 5 compared to Tlr4 null mice. This study demonstrates that inflammatory pathways activated in the host are critically important in mastitis disease progression and suggests that lactation insufficiency associated with mastitis may be a consequence of TLR4-mediated inflammation, rather than the bacterial infection itself.

Objective: Sensory illusions may reveal fundamental features of the nervous system. The thermal grill illusion is such a pain illusion, where interlaced warm and cool temperature bars (thermal grill) produce a paradoxical burning sensation. Previous studies have only systematically investigated the thermal grill illusion in pain-free volunteers. The objective of this study was to investigate whether the response to the thermal grill illusion was tolerable in patients with chronic pain and whether the response differed between patients with chronic pain and pain-free volunteers., Subjects: Sixteen pain-free participants and 18 chronic pain patients (seven not receiving opioids and 11 receiving opioids)., Methods: The thermal grill response was investigated using a custom-built thermal grill. Heat and cold pain thresholds were also determined., Results: Chronic pain patients reported less intense pain, heat, and unpleasantness to the thermal grill compared with pain-free participants; in particular, there was an overall main effect for significantly less heat from the thermal grill compared with pain-free participants (P = 0.016). At the 22/38°C combination, although the majority of pain-free participants experienced the illusion to some degree, the majority of pain patients in both groups did not (median pain score 0). Although perceived heat from the thermal grill was significantly lower in chronic pain patients, both heat and cold pain thresholds did not differ among the three populations., Conclusions: This preliminary data suggest that the thermal grill response may provide insights into pain sensitivity that are not detected by conventional thermal quantitative sensory testing., (Wiley Periodicals, Inc.)

Reciprocal signalling between immunocompetent cells in the central nervous system (CNS) has emerged as a key phenomenon underpinning pathological and chronic pain mechanisms. Neuronal excitability can be powerfully enhanced both by classical neurotransmitters derived from neurons, and by immune mediators released from CNS-resident microglia and astrocytes, and from infiltrating cells such as T cells. In this Review, we discuss the current understanding of the contribution of central immune mechanisms to pathological pain, and how the heterogeneous immune functions of different cells in the CNS could be harnessed to develop new therapeutics for pain control. Given the prevalence of chronic pain and the incomplete efficacy of current drugs--which focus on suppressing aberrant neuronal activity--new strategies to manipulate neuroimmune pain transmission hold considerable promise.

The electroencephalogram (EEG) records the electrical activity of the brain and enables effects of anaesthetic drugs on brain functioning to be monitored. Identification of genes contributing to EEG variability during anaesthesia is important to the clinical application of anaesthesia monitoring and may provide an avenue to identify molecular mechanisms underlying the generation and regulation of brain oscillations. Central immune signalling can impact neuronal activity in the brain and accumulating evidence suggests an important role for cytokines as neuronal modulators. We tested 21 single-nucleotide polymorphisms (SNPs) in immune-related genes for associations with three anaesthesia-induced EEG patterns; spindle amplitude, delta power and alpha power, during general anaesthesia with desflurane in 111 patients undergoing general, gynaecological or orthopaedic surgery. Wide inter-patient variability was observed for all EEG variables. MYD88 rs6853 (p = 6.7 × 10(-4)) and IL-1β rs1143627 in conjunction with rs6853 (p = 1.5 × 10(-3)) were associated with spindle amplitude, and IL-10 rs1800896 was associated with delta power (p = 1.3 × 10(-2)) suggesting involvement of cytokine signalling in modulation of EEG patterns during desflurane anaesthesia. BDNF rs6265 was associated with alpha power (p = 3.9 × 10(-3)), suggesting differences in neuronal plasticity might also influence EEG patterns during desflurane anaesthesia. This is the first study we are aware of that has investigated genetic polymorphisms that may influence the EEG during general anaesthesia.

Translating promising preclinical drug discoveries to successful clinical trials remains a significant hurdle in pain research. Although animal models have significantly contributed to understanding chronic pain pathophysiology, the majority of research has focused on male rodents using testing procedures that produce sex difference data that do not align well with comparable clinical experiences. Additionally, the use of animal pain models presents ongoing ethical challenges demanding continuing refinement of preclinical methods. To this end, this study sought to test a quantitative allodynia assessment technique and associated statistical analysis in a modified graded nerve injury pain model with the aim to further examine sex differences in allodynia. Graded allodynia was established in male and female Sprague Dawley rats by altering the number of sutures placed around the sciatic nerve and quantified by the von Frey test. Linear mixed effects modeling regressed response on each fixed effect (sex, oestrus cycle, pain treatment). On comparison with other common von Frey assessment techniques, utilizing lower threshold filaments than those ordinarily tested, at 1 s intervals, appropriately and successfully investigated female mechanical allodynia, revealing significant sex and oestrus cycle difference across the graded allodynia that other common behavioral methods were unable to detect. Utilizing this different von Frey approach and graded allodynia model, a single suture inflicting less allodynia was sufficient to demonstrate exaggerated female mechanical allodynia throughout the phases of dioestrus and pro-oestrus. Refining the von Frey testing method, statistical analysis technique and the use of a graded model of chronic pain, allowed for examination of the influences on female mechanical nociception that other von Frey methods cannot provide.

Tiger sharks (Galecerdo cuvier) are apex predators characterized by their broad diet, large size and rapid growth. Tiger shark maximum size is typically between 380 & 450 cm Total Length (TL), with a few individuals reaching 550 cm TL, but the maximum size of tiger sharks in Hawaii waters remains uncertain. A previous study suggested tiger sharks grow rather slowly in Hawaii compared to other regions, but this may have been an artifact of the method used to estimate growth (unvalidated vertebral ring counts) compounded by small sample size and narrow size range. Since 1993, the University of Hawaii has conducted a research program aimed at elucidating tiger shark biology, and to date 420 tiger sharks have been tagged and 50 recaptured. All recaptures were from Hawaii except a single shark recaptured off Isla Jacques Cousteau (24°13'17″N 109°52'14″W), in the southern Gulf of California (minimum distance between tag and recapture sites  =  approximately 5,000 km), after 366 days at liberty (DAL). We used these empirical mark-recapture data to estimate growth rates and maximum size for tiger sharks in Hawaii. We found that tiger sharks in Hawaii grow twice as fast as previously thought, on average reaching 340 cm TL by age 5, and attaining a maximum size of 403 cm TL. Our model indicates the fastest growing individuals attain 400 cm TL by age 5, and the largest reach a maximum size of 444 cm TL. The largest shark captured during our study was 464 cm TL but individuals >450 cm TL were extremely rare (0.005% of sharks captured). We conclude that tiger shark growth rates and maximum sizes in Hawaii are generally consistent with those in other regions, and hypothesize that a broad diet may help them to achieve this rapid growth by maximizing prey consumption rates.

A major development in drug addiction research in recent years has been the discovery that immune signaling within the central nervous system contributes significantly to mesolimbic dopamine reward signaling induced by drugs of abuse, and hence is involved in the presentation of reward behaviors. Additionally, in the case of opioids, these hypotheses have advanced through to the discovery of the novel site of opioid action at the innate immune pattern recognition receptor Toll-like receptor 4 as the necessary triggering event that engages this reward facilitating central immune signaling. Thus, the hypothesis of major proinflammatory contributions to drug abuse was born. This review will examine these key discoveries, but also address several key lingering questions of how central immune signaling is able to contribute in this fashion to the pharmacodynamics of drugs of abuse. It is hoped that by combining the collective wisdom of neuroscience, immunology and pharmacology, into Neuroimmunopharmacology, we may more fully understanding the neuronal and immune complexities of how drugs of abuse, such as opioids, create their rewarding and addiction states. Such discoveries will point us in the direction such that one day soon we might successfully intervene to successfully treat drug addiction. This article is part of a Special Issue entitled 'NIDA 40th Anniversary Issue'., (Copyright © 2013 Elsevier Ltd. All rights reserved.)