CGRP and Shh Mediate the Dental Pulp Cell Response to Neuron Stimulation.

Dental pain is a persistent, detrimental public health issue that requires a better understanding of the mechanisms of tooth pain and inflammation in order to develop more effective treatments. Calcitonin gene-related peptide (CGRP) and dental pulp cells are promising candidates for mediating tooth pain and generating reparative dental tissues, respectively, but their behavior in the context of pulpitis remains elusive. The mouse incisor requires Sonic hedgehog (Shh) secreted from sensory nerves to continuously regenerate. However, it is unknown whether sensory nerves also regulate the comparatively nonregenerative mouse molar through CGRP and Shh. This is an important knowledge gap to fill since mouse incisors differ biologically from human teeth, while mouse and human molars are similar. In this work, we identified that molar pulp cells express CGRP receptor and Gli1, a Hedgehog (Hh) signaling protein found to label a dental stem cell population in the mouse incisor. We also observed in a mouse molar injury model that Hh signaling was activated and Shh expression was upregulated in vivo. We then determined in vitro that Shh and CGRP regulate differentiation of primary mouse molar and incisor pulp cells and a human dental pulp stem cell line. Furthermore, conditioned media from stimulated sensory neurons induced Hh signaling activation and inflammatory gene expression in primary molar pulp cells, which was abolished by inhibition of either Shh or CGRP. Our results suggest that CGRP and Shh signaling may promote an inflammatory response after injury in the molar and that activated sensory nerves secrete CGRP and Shh to regulate molar pulp cell expansion and differentiation into odontoblast-like cells for dentin repair. Thus, CGRP/Shh signaling should be considered for new strategies that seek to manage pain or dentin regeneration in the molar.

Evaluation of Self-Reported Agricultural Tasks, Safety Concerns, and Health and Safety Behaviors of Young Adults in U.S. Collegiate Agricultural Programs.

Young adults enrolled in collegiate agricultural programs are a critical audience for agricultural health and safety training. Understanding the farm tasks that young adults engage in is necessary for tailoring health and safety education. The project analyzed evaluation survey responses from the Gear Up for Ag Health and Safety™ program, including reported agricultural tasks, safety concerns, frequency of discussing health and safety concerns with healthcare providers, safety behaviors, and future career plans. The most common tasks reported included operation of machinery and grain-handling. Most participants intended to work on a family-owned agricultural operation or for an agribusiness/cooperative following graduation. Reported safety behaviors (hearing protection, eye protection, and sunscreen use when performing outdoor tasks) differed by gender and education type. Male community college and university participants reported higher rates of "near-misses" and crashes when operating equipment on the roadway. One-third of participants reported discussing agricultural health and safety issues with their medical provider, while 72% were concerned about the health and safety of their family and co-workers in agriculture. These findings provide guidance for better development of agricultural health and safety programs addressing this population-future trainings should be uniquely tailored, accounting for gender and educational differences.

Effects of CGRP-Primed Dental Pulp Stem Cells on Trigeminal Sensory Neurons.

Dental pulp stem cells (DPSCs) are important in tooth physiology, contributing to development, repair, regeneration, and immunomodulatory processes. However, their role in inflammatory mechanisms underlying pulpitis is not well understood. We evaluated the influence of DPSCs stimulated with calcitonin gene-related peptide (CGRP), a proinflammatory neuropeptide, on the expression of mediators released from DPSCs and the effect of these mediators on sensory neuron activity. Human DPSCs were treated with either control media or media containing CGRP (10-8 M) for 7 d, and the conditioned media (CM) containing DPSC-released mediators was collected. The expression of cytokines and chemokines from DPSCs was evaluated by reverse transcription quantitative polymerase chain reaction. The effects of the CM from CGRP-primed DPSCs (primed DPSC-CM) were evaluated on sensory afferents by using primary cultures of mouse trigeminal neurons and an organotypic model of cultured human pulp slices. Mouse trigeminal neurons and human pulp explants were pretreated for 24 h with control or primed DPSC-CM and then stimulated with capsaicin. Afferent activity was measured by quantifying the response to capsaicin via live cell calcium imaging in mouse neurons and CGRP released from pulp explants. Gene expression analysis showed that primed DPSCs overexpressed some proinflammatory cytokines and chemokines, including chemokines CXCL1 and CXCL8, which are both agonists of the receptor CXCR2 expressed in sensory neurons. Primed DPSC-CM increased human pulp sensory afferent activity as compared with control DPSC-CM. Similarly, primed DPSC-CM increased the intensity of calcium responses in cultured mouse trigeminal neurons. Furthermore, the CXCR2 antagonist SB225002 prevented trigeminal neuron sensitization to capsaicin induced by primed DPSC-CM. In conclusion, mediators released by DPSCs, primed with the proinflammatory mediator CGRP, induce neuronal sensitization through CXCR2 receptor. These data suggest that DPSCs might contribute to pain symptoms that develop in pulpitis.

The early and mid-term fate of the axillary artery following axillary artery cut-down and cardiac catheterization in infants and young children.

OBJECTIVES: To study the early and mid-term vascular complications of axillary artery catheterization in children <2 years by clinical and ultrasound examination. BACKGROUND: Femoral arterial access for cardiac catheterization in young children is associated with significant morbidity. Early complications of axillary artery catheterization have been reported but no long-term vascular follow-up data are available. METHODS: Prospective case-control study using standard vascular ultrasound techniques to examine the upper limbs in study participants (n = 10). RESULTS: In total, 23% of axillary artery catheterizarions (56 procedures in 54 patients) resulted in acute arterial insufficiency requiring heparin. Of the survivors under follow-up (n = 33), none had symptoms of chronic arterial insufficiency. At a median follow-up of 8 years postprocedure, three out of the ten study participants had a weak brachial pulse in the test arm but no significant difference in arm measurements. Color Doppler revealed occlusion of the axillary artery in the test arm with collateralization in three patients. The brachial peak systolic velocity (V(max)) was significantly lower in the test arm than the control arm of all the patients with a mean difference of 30 cm/sec (P = 0.007). CONCLUSION: Our study is the first to examine the long-term vascular sequelae of axillary artery catheterization using ultrasound examination and highlights the importance of careful surveillance of vascular access sites. Although axillary artery cut-down for cardiac catheterization in infants and young children does not appear to result in clinical signs of chronic arterial insufficiency, we demonstrate clear evidence of flow abnormalities on vascular ultrasound which are of uncertain long-term significance.

Public health surveillance of dental pain via Twitter.

On Twitter, people answer the question, "What are you doing right now?" in no more than 140 characters. We investigated the content of Twitter posts meeting search criteria relating to dental pain. A set of 1000 tweets was randomly selected from 4859 tweets over 7 non-consecutive days. The content was coded using pre-established, non-mutually-exclusive categories, including the experience of dental pain, actions taken or contemplated in response to a toothache, impact on daily life, and advice sought from the Twitter community. After excluding ambiguous tweets, spam, and repeat users, we analyzed 772 tweets and calculated frequencies. Of the sample of 772 tweets, 83% (n = 640) were primarily categorized as a general statement of dental pain, 22% (n = 170) as an action taken or contemplated, and 15% (n = 112) as describing an impact on daily activities. Among the actions taken or contemplated, 44% (n = 74) reported seeing a dentist, 43% (n = 73) took an analgesic or antibiotic medication, and 14% (n = 24) actively sought advice from the Twitter community. Twitter users extensively share health information relating to dental pain, including actions taken to relieve pain and the impact of pain. This new medium may provide an opportunity for dental professionals to disseminate health information.

Differential TRPV1 and TRPV2 channel expression in dental pulp.

Hypersensitivity to thermal and mechanical stimuli can occur in painful pulpitis. To explore the neuro-anatomical basis of heat and mechanical sensitivity, we evaluated expression of TRPV1 (heat) and TRPV2 (heat/mechanical) channels in the cell bodies and terminal arborizations of neurons that innervate the dental pulp (DP) and periodontal tissues (PDL). We report that ~50% of trigeminal ganglion (TG) neurons retrogradely labeled from the DP express TRPV2, and this was significantly greater than the general expression of this channel in the TG (15%) and slightly more than what is expressed in the PDL by retrograde labeling (40%). The TRPV1 receptor, however, was less prevalent in neurons innervating the DP than their general expression in the TG (17% vs. 26%) and was more extensively expressed in neurons innervating the PDL (26%). Co-labeling studies showed that 70% of neurons that innervate the DP are myelinated. Approximately 1/3 of the retrogradely labeled neurons from the DP were calcitonin-gene-related-peptide-positive (peptide-expressing), but very few expressed the IB4 marker of non-peptidergic unmyelinated afferents. These findings suggest that the DP has a unique neurochemical innervation with regard to TRP receptor expression, which has significant implications for the mechanisms contributing to odontogenic pain and management strategies.

Neuropeptide Y Y1 receptor effects on pulpal nociceptors.

Neuropeptide Y (NPY) is an important modulatory neuropeptide that regulates several physiological systems, including the activity of sensory neurons. We evaluated whether activation of the NPY Y1 receptor could modulate the activity of capsaicin-sensitive nociceptors in trigeminal ganglia and dental pulp. We tested this hypothesis by measuring capsaicin-stimulated calcitonin gene-related peptide release (CGRP) as a measure of nociceptor activity. Capsaicin-evoked CGRP release was inhibited by 50% (p < 0.05) in trigeminal ganglia and by 26% (p < 0.05) in dental pulp when tissues were pre-treated with [Leu(31),Pro(34)]NPY. The Y1 receptor was found to co-localize with the capsaicin receptor TRPV1 in trigeminal ganglia. These results demonstrate that activation of the Y1 receptor results in the inhibition of the activity of capsaicin-sensitive nociceptors in the trigeminal ganglia and dental pulp. These findings are relevant to the physiological modulation of dental nociceptors by endogenous NPY and demonstrate an important novel analgesic target for the treatment of dental pain.

Neuropeptide Y modulates effects of bradykinin and prostaglandin E2 on trigeminal nociceptors via activation of the Y1 and Y2 receptors.

BACKGROUND AND PURPOSE: Although previous studies have demonstrated that neuropeptide Y (NPY) modulates nociceptors, the relative contributions of the Y1 and Y2 receptors are unknown. Therefore, we evaluated the effect of Y1 and Y2 receptor activation on nociceptors stimulated by bradykinin (BK) and prostaglandin E2 (PGE2). EXPERIMENTAL APPROACH: Combined immunohistochemistry (IHC) with in situ hybridization (ISH) demonstrated that Y1- and Y2-receptors are collocated with bradykinin (2) (B2)-receptors in rat trigeminal ganglia (TG). The relative functions of the Y1 and Y2 receptors in modulating BK/PGE2-evoked CGRP release and increased intracellular calcium levels in cultured TG neurons were evaluated. KEY RESULTS: The Y1 and Y2 receptors are co-expressed with B2 in TG neurons, suggesting the potential for direct NPY modulation of BK responses. Pretreatment with the Y1 agonist [Leu31,Pro34]-NPY, inhibited BK/PGE2-evoked CGRP release. Conversely, pretreatment with PYY(3-36), a Y2 agonist, increased BK/PGE2 evoked CGRP release. Treatment with NPY evoked an overall inhibitory effect, although of lesser magnitude. Similarly, [Leu31,Pro34]-NPY inhibited BK/PGE2-evoked increases in intracellular calcium levels whereas PYY(3-36) increased responses. NPY inhibition of BK/PGE2-evoked release of CGRP was reversed by the Y1 receptor antagonist, BIBO3304, and higher concentrations of BIBO3304 significantly facilitated CGRP release. The Y2 receptor antagonist, BIIE0246, enhanced the inhibitory NPY effects. CONCLUSIONS AND IMPLICATIONS: These results demonstrate that NPY modulation of peptidergic neurons is due to net activation of inhibitory Y1 and excitatory Y2 receptor systems. The relative expression or activity of these opposing receptor systems may mediate dynamic responses to injury and pain.

Outcome after extended arch repair for aortic coarctation.

OBJECTIVES: To assess survival and long term arch patency rates in a consecutive group of children after extended arch repair for coarctation of the aorta. METHODS: Review of 191 consecutive children (154 (81%) under 1 year of age) operated on between 1990 and 2002 by a single surgeon using extended arch reconstructive techniques. For assessment of survival patients were divided into three groups: 1, coarctation alone, n = 104; 2, coarctation and ventricular septal defect, n = 38; and 3, coarctation in association with complex intracardiac anomalies, n = 49. A prospective and systematic clinical and echocardiographic evaluation of the aortic arch was undertaken. RESULTS: Median time to follow up was 4.2 years (range 1-10.6 years). Overall actuarial survival was 92%, 88%, and 88% at two, five, and 10 years. Mortality was significantly higher in those patients with complex intracardiac anatomy. Arch obstruction recurred in seven of 165 (4.2%) patients: four of 139 (2.9%) term and three of 10 (30%) premature infants (p < 0.001). CONCLUSIONS: Survival after extended arch reconstruction for coarctation is excellent. At long follow up recurrent arch obstruction is rare, with prematurity the only risk factor.

Poor sensitivity of routine fetal anomaly ultrasound screening for antenatal detection of atrioventricular septal defect.

OBJECTIVE: To report the antenatal detection rate in a consecutive series of liveborn infants with atrioventricular septal defect (AVSD). DESIGN: Review and analysis of referrals for detailed fetal echocardiography and postnatal diagnosis of AVSD. SETTING: Tertiary referral centre for congenital heart disease centre with data prospectively collected between 1996 to 2001. RESULTS: 92 consecutively liveborn infants with AVSDs were identified of which 27 (29%) were detected by routine obstetric antenatal ultrasound. The antenatal diagnosis rate was worse for liveborn infants with trisomy 21 (12 of 49 (25%) v 15 of 43 (35%) chromosomally normal children) and for infants with AVSD without other structural heart disease (18 of 74 (24%) v 9 of 18 (50%) infants with associated structural heart disease). CONCLUSION: Despite the potential ability of fetal ultrasound to detect AVSDs, the antenatal diagnosis rate is poor. This is particularly true for infants with trisomy 21 and is of importance when counselling parents with an apparently normal fetal ultrasound scan.

Successful treatment of left atrial disk thrombus on an Amplatzer atrial septal defect occluder with abciximab and heparin.

Acute device thrombosis is a rare but important complication after transcatheter atrial septal defect closure. In this case a mobile thrombus was noted on the left side of an Amplatzer atrial septal occluder after device release in a 12 year old boy with an uncomplicated atrial septal defect. The thrombus was successfully treated with an infusion of heparin and the glycoprotein IIa/IIIb receptor antagonist abciximab. Transoesophageal ultrasound performed the following day showed complete resolution of the clot. There are no reports to guide treatment of acute thrombosis in this setting. This combination of treatments was effective without complication in this case.

Surgical and transcatheter (Amplatzer) closure of atrial septal defects: a prospective comparison of results and cost.

OBJECTIVE: To compare effectiveness, complications, and cost of Amplatzer with surgical atrial septal defect (ASD) closure. DESIGN: Prospective study. SETTING: Tertiary cardiac referral centre. PATIENTS: 43 consecutive patients (excluding non-UK residents) aged between 2.1 and 56.8 years (median 7) undergoing ASD closure. MAIN OUTCOME MEASURES: Procedural success, complications, regression of right ventricular dilatation (up to one year postprocedure), cost, inpatient stay, and home convalescent time. RESULTS: Amplatzer ASD closure was successful in 24 of 27 (89%) patients. Surgical closure was successful in all 19 cases. Cardiac complications affecting management occurred in three (11%) of the Amplatzer group (two procedural failures, one device embolisation) and 4 of 19 (21%) surgical patients (one pericardial pain, one global pericardial effusion requiring drainage, and one patient with anaemia requiring haematinics in addition to an incidental pericardial effusion and one further incidental pericardial effusion) (p = NS). There were complications that did not affect management in a further 5 of 19 surgical patients. There was no significant difference in regression of right ventricular dilatation by six months postprocedure (median right ventricular end diastolic diameter decrease: Amplatzer group 17.5%, surgical group 15.1%; median cardiothoracic ratio decrease: Amplatzer 7.9%, surgical 7.5%). Both hospital stay and home convalescent times were significantly shorter after Amplatzer closure (median hospital stay: Amplatzer one day, surgery six days; median convalescent time: Amplatzer two weeks, surgery 5.5 weeks). Median cost was similar for both groups (Amplatzer pound5375, surgical pound5412). CONCLUSIONS: Amplatzer ASD closure has a lower chance of success with a single procedure than surgery. Overall, there were more complications in the surgical group but the majority of these were minor and did not require any change in management. Resolution of right ventricular dilatation over the study period was similar for both techniques. Time spent in hospital and away from work or school was shorter for the Amplatzer group. The cost of both techniques was similar.

Identification of Streptococcus pneumoniae revisited.

The sensitivities and specificities of several different diagnostic assays for Streptococcus pneumoniae were assessed using 99 clinical isolates of S. pneumoniae and 101 viridans streptococci and were as follows: Pneumoslide, 99 and 87%, respectively; Directigen, 100 and 85%, respectively; Phadebact, 100 and 98%, respectively; deoxycholate drop test, 99 and 98%, respectively; deoxycholate tube test, 100 and 99%, respectively; optochin, 99 and 98%, respectively; and Gram Positive Identification Card, 90 and 96%, respectively. Identification of clinical isolates of S. pneumoniae should be confirmed using one or more diagnostic assays with well-documented high (e.g., > or =95%) sensitivities and specificities.

Mitral regurgitation after anthracycline treatment for childhood malignancy.

OBJECTIVE: To investigate the new onset of mitral regurgitation in patients with otherwise normal echocardiograms after anthracycline treatment and to assess its relation to other selected indicators of myocardial damage. DESIGN: Prospective echocardiographic and electrocardiographic study. SETTING: Tertiary paediatric cardiac referral centre. PATIENTS: 305 patients, aged 2-33 years (median 14 years), treated with cumulative anthracycline doses of between 150-450 mg/m(2) (median 180 mg/m(2)) for childhood malignancy. MAIN OUTCOME MEASURES: Colour flow Doppler detection of mitral regurgitation and its relation to changes in echocardiographic indices of left ventricular function (systolic and diastolic dimensions, fractional shortening) and to changes in the 12 lead ECG; and the prevalence of mitral regurgitation in the anthracycline treated patients in comparison with previously studied normal volunteers of similar age. RESULTS: 34 patients (11.6%) developed ultrasound detectable mitral regurgitation, which was not apparent clinically, during or after anthracycline treatment, compared with only 1.8% of a normal population of similar age (p < 0.0001). Nine of the 34 also developed non-specific T wave abnormalities. All 34 patients had normal systolic function at the time of initial detection of mitral regurgitation, but four later developed impaired left ventricular function (5, 11, 20, and 27 months after the first detection of mitral regurgitation). CONCLUSIONS: Mitral regurgitation occurs much more often in patients treated with anthracyclines than in the normal population. Echocardiographic detection of new mitral regurgitation with or without ECG abnormalities may be an early predictor of anthracycline cardiomyopathy.

Recommendations of the British Paediatric Cardiac Association for therapeutic cardiac catheterisation in congenital cardiac disease.

The aims of these recommendations are to improve the outcome for patients after, and to provide acceptable standards of practice of therapeutic cardiac catheterisation performed to treat congenital cardiac disease. The scope of the recommendations includes all interventional procedures, recognising that for some congenital malformations, surgical treatment is equally as effective as, or occasionally preferable to, interventional treatment. The limitations of the recommendations are that, at present, no data are available which compare the results of interventional treatment with surgery, and certainly none which evaluate the numbers and types of procedures that need to be performed for the maintenance of skills. Thus, there is a recognised need to collect comprehensive data with which these recommendations could be reviewed in the future, and re-written as evidence-based guidelines. Such a review will have to take into account the methods of collection of data, their effectiveness, and the latest developments in technology. The present recommendations should, therefore, be considered as consensus statements, and as describing accepted practice, which could be used as a basis for ensuring and improving the quality of future care.

Cardiac catheter guided surgical closure of an apical ventricular septal defect.

Surgical closure of muscular ventricular septal defects can be difficult. We report a technique in which a preoperatively placed cardiac catheter allowed accurate localization of a residual apical muscular defect at operation. The approach not only allowed improved visualization of the defect from the right side of the heart, but also helped to minimize the size of the left ventriculotomy required for satisfactory closure.

Illness understanding in children and adolescents with heart disease.

AIMS: To evaluate illness knowledge and understanding in children and adolescents with congenital and acquired heart disease, and whether the degree of understanding is related to age, sex, or complexity of the heart disease. DESIGN: Prospective cohort study. SETTING: Tertiary paediatric cardiac centre. METHODS: Patients' understanding of their congenital heart disease was assessed in a representative sample of volunteers aged between 7-18 years using semistructured interviews based upon Leventhal's illness representation model. RESULTS: 63 of 69 interviews were suitable for analysis. There were similar numbers of boys and girls and a wide distribution of heart defects. Only 30% of patients had a good understanding of their illness; 77% did not know the medical name of their condition, and 33% had a wrong or poor understanding of their illness. Understanding was unrelated to age, sex, or the nature of the heart disease. Understanding of illness duration was significantly related to age, but not to sex or to the nature of the disease. CONCLUSIONS: Illness understanding is poor in children and adolescents with heart disease, and many have an entirely wrong concept of their disease. Intensified efforts to ensure better patient and parental understanding are needed.