Sex and gender differences in healthcare utilisation trajectories: a cohort study among Quebec workers living with chronic pain

OBJECTIVES

Chronic pain (CP) is a poorly recognised and frequently inadequately treated condition affecting one in five adults. Reflecting on sociodemographic disparities as barriers to CP care in Canada was recently established as a federal priority. The objective of this study was to assess sex and gender differences in healthcare utilisation trajectories among workers living with CP.

DESIGN

Retrospective cohort study.

PARTICIPANTS

This study was conducted using the TorSaDE Cohort which links the 2007-2016 Canadian Community Health Surveys and Quebec administrative databases (longitudinal claims). Among 2955 workers living with CP, the annual number of healthcare contacts was computed during the 3 years after survey completion.

OUTCOME

Group-based trajectory modelling was used to identify subgroups of individuals with similar patterns of healthcare utilisation over time (healthcare utilisation trajectories).

RESULTS

Across the study population, three distinct 3-year healthcare utilisation trajectories were found: (1) low healthcare users (59.9%), (2) moderate healthcare users (33.6%) and (3) heavy healthcare users (6.4%). Sex and gender differences were found in the number of distinct trajectories and the stability of the number of healthcare contacts over time. Multivariable analysis revealed that independent of other sociodemographic characteristics and severity of health condition, sex-but not gender-was associated with the heavy healthcare utilisation longitudinal trajectory (with females showing a greater likelihood; OR 2.6, 95% CI 1.6 to 4.1).

CONCLUSIONS

Our results underline the importance of assessing sex-based disparities in help-seeking behaviours, access to healthcare and resource utilisation among persons living with CP.

Review: Targeted nutrition in gestating sows: opportunities to enhance sow performance and piglet vitality

Birth weight is a key factor for piglet survival, and therefore, there is ongoing interest in how nutrition during gestation can influence birth weight. Interestingly, sows are generally fed one single diet throughout gestation. This paper reviews past attempts to increase foetal growth to term and discusses opportunities to target nutritional manipulations at specific windows of gestation where key developmental events occur. Birth weight limits chances to survive mainly in piglets with birth weight below 1 kg. These piglets represent around 16% of the population. Given the normal distribution of birth weight, the mean birth weight needs to be increased by at least 50-100 g to have a meaningful impact on this proportion of the population and on perinatal survival. Based on existing variation in reported mean birth weight across a number of studies, it is argued that it is unrealistic to expect an increase in mean birth weight of more than 100 g. Attempts in the past to increase birth weight have focussed on the last trimester of gestation, when foetal growth is accelerated. Increase in feed allowance or nutritional concepts that target placenta vascularisation have not been successful. It is argued that nutritional manipulations should rather focus on the middle of gestation, since in that period, placenta growth occurs and since placenta size limits the foetal size. Alternatively, nutritional manipulations can target placentation during the embryonic phase.

Effect of low colostrum intake on gastrointestinal development and uterine and cervical morphometrical architecture in the neonatal gilt

To assess the importance of natural variation in colostrum intake on piglet gastrointestinal and reproductive development, two equally sized female piglets from each of 27 litters were selected, one with low (average 226 g) and one with high (average 401 g) colostrum intake. At weaning (23 d of age), piglets were euthanised to perform macromorphological measurements on ileum, colon, cervix and uterus tissues, and to obtain tissue samples from the cervix and uterus for histology. Sections of uterine and cervical preparations were analysed using digital image analysis. Despite being selected for the same birth weight (average 1.1 kg, standard deviation 0.18 kg), piglets with low colostrum intake weighed 5.91 ± 0.17 kg and piglets with high colostrum intake weighed 6.96 ± 0.19 kg at weaning (P < 0.05). Most of the micro- and macroscopic measures such as length and weight of ileum and colon, cervix and uterus, luminal size of cervix and uterus, number of cervical crypts and uterine glands, were greater in gilts with high colostrum intake. The histological architecture of the uterus and cervix in gilts with high colostrum intake showed more complexity, reflecting more advanced development in these piglets. In conclusion, these data demonstrate that independent of birth weight, natural variation in colostrum intake is related to the overall development of neonatal piglets, affecting body growth, as well as growth and development of the gut and reproductive tract.

NFL strongly correlates with TNF-R1 in the plasma of AD patients, but not with cognitive decline

Peripheral inflammation mechanisms involved in Alzheimer's disease (AD) have yet to be accurately characterized and the identification of blood biomarker profiles could help predict cognitive decline and optimize patient care. Blood biomarkers described to date have failed to provide a consensus signature, which is mainly due to the heterogeneity of the methods used or the cohort. The present work aims to describe the potential informativity of peripheral inflammation in AD, focusing in particular on the potential association between the level of plasma neurofilament light (NFL), peripheral inflammation (by quantifying IL-1β, IL-6, TNFα, CCL5, TNF-R1, sIL-6R, TIMP-1, IL-8 in blood) and cognitive decline (assessed by the MMSE and ADAScog scales) through a 2-year follow-up of 40 AD patients from the Cytocogma cohort (CHU Poitiers, Pr M. Paccalin). Our results show for the first time a strong correlation between plasma NFL and TNF-R1 at each time of follow-up (baseline, 12 and 24 months), thus opening an interesting perspective for the prognosis of AD patients.

Exploiting digital droplet PCR and Next Generation Sequencing technologies to determine the relative abundance of individual Eimeria species in a DNA sample

DNA-based diagnostic assays for detecting infections with Eimeria species have been limited to providing identification and presence/absence data for samples containing oocysts. Modern technologies that generate quantitative data, such as droplet digital PCR (ddPCR) and Next Generation Sequencing (NGS), utilize a relatively short amplicon size containing sufficient species-specific variation for reliable species level identification. Targeting the cytochrome c oxidase subunit III gene in the mitochondrial genome, we established protocols using these technologies to determine the relative abundance of the number of copies/μL of Eimeria species in a sample. Samples from chickens of known and unknown Eimeria species composition were analyzed to determine the suitability of these technologies as diagnostic assays. All technologies demonstrated robust capability of identifying and quantifying the Eimeria species in samples. The new quantitative assays described herein will produce invaluable detail of Eimeria species infections for an array of situations in commercial chicken production systems, enabling further characterization of the disease profile and allowing for the development or enhancement of new intervention strategies.

A method for experimental warming of developing tree seeds with a common garden demonstration of seedling responses

BACKGROUND

Forest dieback driven by rapid climate warming threatens ecosystems worldwide. The health of forested ecosystems depends on how tree species respond to warming during all life history stages. While it is known that seed development is temperature-sensitive, little is known about possible effects of climate warming on seed development and subsequent seedling performance. Exposure of seeds to high air temperatures may influence subsequent seedling performance negatively, though conversely, warming during seed development may aid acclimation of seedlings to subsequent thermal stress. Technical challenges associated with in-situ warming of developing tree seeds limit understanding of how tree species may respond to seed development in a warmer climate.

RESULTS

We developed and validated a simple method for passively warming seeds as they develop in tree canopies to enable controlled study of climate warming on seedling performance. We quantified thermal effects of the cone-warming method across individual pine trees and stands by measuring the air temperature surrounding seed cones using thermal loggers and the temperature of seed cone tissue using thermocouples. We then investigated seedling phenotypes in relation to the warming method through a common garden study. We assessed seedling morphology, physiology, and mycorrhizal nodulation in response to experimental cone-warming in 20 seed-source-tree canopies on the San Francisco Peaks in northern Arizona, USA. The warming method increased air temperature surrounding developing seed cones by 2.1 °C, a plausible increase in mean air temperature by 2050 under current climate projections. Notable effect sizes of cone-warming were detected for seedling root length, shoot length, and diameter at root collar using Cohen's Local f². Root length was affected most by cone-warming, but effect sizes of cone-warming on root length and diameter at root collar became negligible after the first year of growth. Cone-warming had small but significant effects on mycorrhizal fungal richness and seedling multispectral near-infrared indices indicative of plant health.

CONCLUSIONS

The method was shown to reliably elevate the temperature surrounding seed cones and thereby facilitate experimental in-situ climate warming research on forest trees. The method was furthermore shown to influence plant traits that may affect seedling performance under climate warming.

Selective beta-3 adrenergic receptor blockade increases contractility of human ventricular trabeculae from HFrEF donors

Background

Alterations of the beta-adrenergic system have been extensively described in the setting of heart failure (HF). Upregulation of beta-3 adrenergic receptor (β3-AdrR) expression in human failing hearts depresses myocardial contractility and, during an acute decompensation event, can be considered a maladaptive compensatory mechanism that exacerbates cardiac dysfunction. APD418 is a selective β3-AdrR antagonist currently in development for patients who have acute heart failure with reduced ejection fraction (HFrEF). APD418 is designed to improve myocardial contractility by selectively antagonizing the β3-AdrR and thereby avoiding the cAMP/Ca2+ signaling pathway stimulated by current inotropes.

Purpose

This study evaluated the effect of a selective β3-AdrR antagonist (APD418) on contractile responses in explanted human ventricular trabeculae obtained from normal and HFrEF hearts.

Methods

Left ventricular trabeculae from normal and HFrEF donors were electrically stimulated (1 Hz) ex-vivo to analyze force generated during contractions. First, BRL37344, a selective β3-AdrR agonist, was applied at increasing concentrations (0.01–10 μM) to confirm β3-AdrR mediated negative inotropy in human myocardial tissue. To test the effect of a selective β3-AdrR antagonist on contractile force, myocardial tissue was pre-treated with APD418 or vehicle for 5 minutes, followed by treatment with non-selective β-AdrR agonists isoproterenol (10 nM) or norepinephrine (5 μM).

Results

In heart tissue from normal donors, the β3-AdrR agonist BRL37344 did not affect contractile function at 0.01 and 0.1 μM. However, in heart tissue from HFrEF donors, BRL37344 induced a significant decrease in contractility at 0.01, 0.1 and 1 μM (85.9±1.8% with 0.1 μM BRL37344 vs 104.1±2.9% with vehicle). Selective blockade of β3-AdrR with APD418 had no effect on force of contraction induced by norepinephrine in cardiac tissue from normal donors. In contrast, APD418 potentiated the force of contraction induced by either isoproterenol (49.1±20.6% increase with 0.1 μM APD418 compared to baseline) or norepinephrine (26.5±4.9% increase with 0.01 μM APD418 compared to baseline) in cardiac tissue from HFrEF patients.

Conclusion

This is, to our knowledge, the first evidence showing that selective blockade of β3-AdrR increases contractility of human ventricular trabeculae from HFrEF donors and suggests that further studies evaluating the therapeutic benefit of APD418 in patients with HFrEF are warranted.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Arena Pharmaceuticals

Monitoring coccidia in commercial broiler chicken flocks in Ontario: comparing oocyst cycling patterns in flocks using anticoccidial medications or live vaccination

Coccidiosis, the parasitic disease caused by Eimeria spp., is controlled during broiler chicken production through the inclusion of in-feed anticoccidial medications. Live-coccidiosis vaccination has become an increasingly common alternative to these medications. Monitoring infections with Eimeria spp. in flocks can be accomplished through determining the concentration of oocysts excreted in the fecal material (i.e., oocysts per gram; OPG). The purpose of our study was to sample commercial Ontario broiler chicken flocks at various times of the year to determine weekly OPG counts for flocks that use either an in-feed anticoccidial medication or a live-coccidiosis vaccine. Weekly sampling of 95 flocks from placement to market permitted documentation of oocyst cycling patterns typical of conventional and antibiotic-free flocks, and variation of these patterns in summer and winter. Medicated flocks had higher and later peak oocyst shedding compared with vaccinated flocks. Flocks reared in the summer peaked in oocyst shedding earlier than flocks reared in the winter. Despite what appears to be poorer coccidiosis control in the medicated flocks, the performance data were similar for these flocks compared with vaccinated flocks. This is the first study describing typical patterns of parasite shedding in Ontarian commercial broiler chicken flocks; these data will provide a baseline of expected Eimeria spp. infections in Canadian broiler chicken flocks to ensure optimal coccidiosis prevention.

The effect of added oat hulls or sugar beet pulp to diets containing rapidly or slowly digestible protein sources on broiler growth performance from 0 to 36 days of age

The effects of formulating broiler diets that contain sources of either rapidly or slowly digestible protein and 2 different dietary fiber sources on growth performance were studied in broilers chickens from 0 to 36 d of age. A total of 1,920 one-day-old, male Ross 708 broiler chickens were randomly allocated and housed in 48 floor pens (40 birds/pen) to one of 4 dietary treatments. Birds were allotted according to a completely randomized block design using a factorial arrangement of treatments with 2 protein digestion rates (rapidly or slowly) and 2 dietary fiber sources [3% oat hulls (OH) or 3% sugar beet pulp (SBP)] from 0 to 36 d of age. All diets were formulated to be isocaloric and isonitrogenous. The pen was the experimental unit for all variables studied (12 replicates/treatment). Data were analyzed using the MIXED procedure of SAS, and the model included the main effects of the protein digestion rate, dietary fiber source, and their interaction. There were 3 experimental feeding phases; starter (from day 0–14), grower (from day 14–28), and finisher (from day 28–36). Results indicated that broilers fed diets containing sources that supplied more rapidly digestible protein had 4% greater (P < 0.01) ADG and improved (P < 0.01) the feed conversion ratio (FCR) by 5% throughout the experiment, most notably after the starter phase. Diets containing 3% OH increased (P < 0.05) the ADFI and ADG (P < 0.05) in the starter phase compared with broilers fed diets containing 3% SBP, without affecting the FCR. The ADG and FCR of broilers fed diets containing sources of slowly digestible protein were improved (P < 0.05) to the level of broilers fed rapidly digestible protein containing diets with the addition of 3% OH. It is concluded that broiler diets should be formulated to contain a high concentration of ingredients that supply rapidly digestible protein, but if this is cost-prohibitive, then 3% OH could be used to increase the ADFI and ADG and potentially protein digestion rates to reduce the FCR.

Current and emerging avenues for Alzheimer's disease drug targets

Alzheimer's disease (AD), the most frequent cause of dementia, is escalating as a global epidemic, and so far, there is neither cure nor treatment to alter its progression. The most important feature of the disease is neuronal death and loss of cognitive functions, caused probably from several pathological processes in the brain. The main neuropathological features of AD are widely described as amyloid beta (Aβ) plaques and neurofibrillary tangles of the aggregated protein tau, which contribute to the disease. Nevertheless, AD brains suffer from a variety of alterations in function, such as energy metabolism, inflammation and synaptic activity. The latest decades have seen an explosion of genes and molecules that can be employed as targets aiming to improve brain physiology, which can result in preventive strategies for AD. Moreover, therapeutics using these targets can help AD brains to sustain function during the development of AD pathology. Here, we review broadly recent information for potential targets that can modify AD through diverse pharmacological and nonpharmacological approaches including gene therapy. We propose that AD could be tackled not only using combination therapies including Aβ and tau, but also considering insulin and cholesterol metabolism, vascular function, synaptic plasticity, epigenetics, neurovascular junction and blood-brain barrier targets that have been studied recently. We also make a case for the role of gut microbiota in AD. Our hope is to promote the continuing research of diverse targets affecting AD and promote diverse targeting as a near-future strategy.

The key-features approach to assess clinical decisions: validity evidence to date

The key-features (KFs) approach to assessment was initially proposed during the First Cambridge Conference on Medical Education in 1984 as a more efficient and effective means of assessing clinical decision-making skills. Over three decades later, we conducted a comprehensive, systematic review of the validity evidence gathered since then. The evidence was compiled according to the Standards for Educational and Psychological Testing's five sources of validity evidence, namely, Content, Response process, Internal structure, Relations to other variables, and Consequences, to which we added two other types related to Cost-feasibility and Acceptability. Of the 457 publications that referred to the KFs approach between 1984 and October 2017, 164 are cited here; the remaining 293 were either redundant or the authors simply mentioned the KFs concept in relation to their work. While one set of articles reported meeting the validity standards, another set examined KFs test development choices and score interpretation. The accumulated validity evidence for the KFs approach since its inception supports the decision-making construct measured and its use to assess clinical decision-making skills at all levels of training and practice and with various types of exam formats. Recognizing that gathering validity evidence is an ongoing process, areas with limited evidence, such as item factor analyses or consequences of testing, are identified as well as new topics needing further clarification, such as the use of the KFs approach for formative assessment and its place within a program of assessment.

Wrestling with the complexity of evaluation for organizations at the boundary of science, policy, and practice

Boundary organizations are situated between science, policy, and practice and have a goal of supporting communication and collaboration among these sectors. They have been promoted as a way to improve the effectiveness of conservation efforts by building stronger relationships between scientists, policy makers, industry, and practitioners (Cook et al. 2013). Although their promise has been discussed in theory, the work of and expectations for boundary organizations are less defined in practice. Biodiversity conservation is characterized by complexity, uncertainty, dissent, and tight budgets, so boundary organizations face the challenging task of demonstrating their value to diverse stakeholders. We examined the challenges boundary organizations face when seeking to evaluate their work and thus aimed to encourage more productive conversations about evaluation of boundary organizations and their projects. Although no off-the-shelf solution is available for a given boundary organization, we identified 4 principles that will support effective evaluation for boundary organizations: engage diverse stakeholders, support learning and reflection, assess contribution to change, and align evaluation with assumption and values.

Longitudinal chemokine profile expression in a blood-brain barrier model from Alzheimer transgenic versus wild-type mice

BACKGROUND

Alzheimer's disease is widely described since the discovery of histopathological lesions in Mrs. Auguste Deter in 1906. However to date, there is no effective treatment to deal with the many cellular and molecular alterations. The complexity is even higher with the growing evidence of involvement of the peripheral blood mononuclear cells (PBMCs). Indeed, monocytes and T cells are shown in the cerebral parenchyma of AD patients, and these cells grafted to the periphery are able to go through the blood-brain barrier (BBB) in transgenic mouse models. It is known that BBB is disrupted at a late stage of AD. Chemokines represent major regulators of the transmigration of PBMCs, but many data were obtained on AD animal models. No data are available on the role of AD BBB in a healthy brain parenchyma. Therefore, the purpose of this study was to analyze the longitudinal chemokine profile expression in a BBB model from AD transgenic mice versus wild-type (WT) mice.

METHODS

A primary mouse BBB model was used with a luminal compartment either AD or WT and an abluminal compartment WT consisting of astrocytes and microglia. PBMCs were extracted by a ficoll gradient and incubated in the transwell with a direct contact with the luminal side, including the endothelial cells and pericytes. Then, the complete BBB model was incubated during 48 h, before supernatants and cell lysates were collected. Chemokines were quantified by X-MAP® luminex technology.

RESULTS

Abluminal CX3CL1 production increased in 12-month-old AD BBB while CX3CL1 levels decreased in luminal lysates. CCL3 in luminal compartment increased with aging and was significantly different compared to AD BBB at 12 months. In addition, abluminal CCL2 in 12-month-old AD BBB greatly decreased compared to levels in WT BBB. On the contrary, no modification was observed for CCL4, CCL5, and CXCL10.

CONCLUSION

These first findings highlighted the impact of AD luminal compartment on chemokine signature in a healthy brain parenchyma, suggesting new therapeutic or diagnostic approaches.

ICP Monitoring and Phase-Contrast MRI to Investigate Intracranial Compliance

OBJECTIVE

The amplitude of intracranial pressure (ICP) can be measured by ICP monitoring. Phase-contrast magnetic resonance imaging (PCMRI) can quantify blood and cerebrospinal fluid (CSF) flows. The aim of this work was to investigate intracranial compliance at rest by combining baseline ICP monitoring and PCMRI in hydrocephalus patients.

MATERIALS AND METHODS

ICP monitoring was performed before infusion testing to quantify ΔICP_rest at the basal condition in 33 suspected hydrocephalus patients (74 years). The day before, patients had had a PCMRI to assess total cerebral blood flow (tCBF), intracranial blood volume change (stroke volume SVblood), and cervical CSF volume change (the stroke volume CSV). Global (blood and CSF) intracranial volume change (ΔIVC) during each cardiac cycle (CC) was calculated. Finally, Compliance: C_rest = ΔIVC/ΔICP_rest was calculated. The data set was postprocessed by two operators according to blind analysis.

RESULTS

Bland-Altman plots showed that measurements presented no significant difference between the two operators. ΔICP_rest = 2.41 ± 1.21 mmHg, tCBF = 469.89 ± 127.54 mL/min, SVblood = 0.82 ± 0.32 mL/cc, CSV = 0.50 ± 0.22 mL/cc, ΔIVC = 0.44 ± 0.22 mL, and C_rest = 0.23 ± 0.15 mL/mmHg. There are significant relations between SVblood and CSV and also SVblood and tCBF.

CONCLUSIONS

During "basal" condition, the compliance amplitude of the intracranial compartment is heterogeneous in suspected hydrocephalus patients, and its value is lower than expected! This new parameter could represent new information, complementary to conventional infusion tests. We hope that this information can be applied to improve the selection of patients for shunt surgery.

Maternal and neonatal outcomes in a treated versus non- treated cohort of women with Gestational Diabetes Mellitus according to the HAPO 5 and 4 criteria

BACKGROUND

Our aim was to evaluate the treatment effect of gestational diabetes mellitus (GDM) according to the Hyperglycemia and Adverse Pregnancy Outcome group (HAPO) screening.

RESULTS

The prevalence of GDM, using HAPO 5 was 23.8%. Of these, 72.8% were treated. Comparison of outcomes between treated and untreated patients showed no differences. The prevalence of GDM according to HAPO 4 criteria was 16.9%. In the untreated group, there were more cases of (pre)eclampsia (P=0.038), more admissions to neonatal care department (P=0.036), pregnancy duration was shorter (P=0.05), and Apgar score at five minutes was significantly lower (P=0.019). The outcomes didn't differ in the MAGG (midly aberrant glycemic group).

CONCLUSIONS

Using HAPO 5 criteria in population-based screening doubled the prevalence of GDM. There were no differences between untreated and treated HAPO 5 and MAGG patients, while in the HAPO 4 group there might be a trend of therapy effectiveness.

Long-term non-invasive interrogation of human dorsal root ganglion neuronal cultures on an integrated microfluidic multielectrode array platform

Scientific studies in drug development and toxicology rely heavily on animal models, which often inaccurately predict the true response for human exposure. This may lead to unanticipated adverse effects or misidentified risks that result in, for example, drug candidate elimination. The utilization of human cells and tissues for in vitro physiological platforms has become a growing area of interest to bridge this gap and to more accurately predict human responses to drugs and toxins. The effects of new drugs and toxins on the peripheral nervous system are often investigated with neurons isolated from dorsal root ganglia (DRG), typically with one-time measurement techniques such as patch clamping. Here, we report the use of our multi-electrode array (MEA) platform for long-term noninvasive assessment of human DRG cell health and function. In this study, we acquired simultaneous optical and electrophysiological measurements from primary human DRG neurons upon chemical stimulation repeatedly through day in vitro (DIV) 23. Distinct chemical signatures were noted for the cellular responses evoked by each chemical stimulus. Additionally, the cell viability and function of the human DRG neurons were consistent through DIV 23. To the best of our knowledge, this is the first report on long-term measurements of the cell health and function of human DRG neurons on a MEA platform. Future generations will include higher electrode numbers in customized arrangements as well as integration with different tissue types on a single device. This platform will provide a valuable testing tool for both rodent and human cells, enabling a more comprehensive risk assessment for drug candidates and toxicants.

Female gender and diabetes mellitus increase the risk of recurrence after laparoscopic incisional hernia repair

BACKGROUND

Laparoscopic hernia repair is used widely for the repair of incisional hernias. Few case studies have focussed on purely 'incisional' hernias. This multicentre series represents a collaborative effort and employed statistical analyses to provide insight into the factors predisposing to recurrence of incisional hernia after laparoscopic repair. A specific hypothesis (ie, laterality of hernias as well as proximity to the xyphoid process and pubic symphysis predisposes to recurrence) was also tested.

METHODS

This was a retrospective study of all laparoscopic incisional hernias undertaken in six centres from 1 January 2004 to 31 December 2010. It comprised a comprehensive review of case notes and a follow-up using a structured telephone questionnaire. Patient demographics, previous medical/surgical history, surgical procedure, postoperative recovery, and perceived effect on quality of life were recorded. Repairs undertaken for primary ventral hernias were excluded. A logistic regression analysis was then fitted with recurrence as the primary outcome.

RESULTS

A total of 186 cases (91 females) were identified. Median follow-up was 42 months. Telephone interviews were answered by 115/186 (62%) of subjects. Logistic regression analyses suggested that only female sex (odds ratio (OR) 3.53; 95% confidence interval (CI) 1.39-8.97) and diabetes mellitus (3.54; 1-12.56) significantly increased the risk of recurrence. Position of the defect had no statistical effect.

CONCLUSIONS

These data suggest an increased risk of recurrence after laparoscopic incisional hernia repair in females and subjects with diabetes mellitus. These data will help inform surgeons and patients when considering laparoscopic management of incisional hernias. We recommend a centrally hosted, prospectively maintained national/international database to carry out additional research.

Neuroinflammation and β amyloid deposition in Alzheimer's disease: in vivo quantification with molecular imaging

BACKGROUND/AIMS

Neuroinflammation plays a crucial role in the pathogenesis of Alzheimer's disease (AD). Its relationship with underlying β amyloid deposition remains unclear. In vivo visualization of microglial activation has become possible with the development of molecular imaging ligands when used with positron emission tomography (PET). The translocator protein (TSPO) is upregulated during neuroinflammation. Consequently, targeting TSPO with radiolabeled ligands for PET is an attractive biomarker for neuroinflammation.

METHODS

A review of the research literature on PET imaging which studied in vivo neuroinflammation in AD subjects and its relationship with amyloid load was performed, including papers published between 2001 and 2012.

RESULTS

Six studies were included using either [(11)C]PK-11195 or another non-TSPO radioligand that binds to the monoaminooxidase B. All the studies evaluated amyloid load with [(11)C]PIB. Microglial activation and astrocytosis are potentially early phenomena in AD. However, the individual levels of amyloid deposition and microglial activation were not correlated.

CONCLUSION

Noninvasive in vivo molecular imaging to visualize neuroinflammation in AD may contribute to our understanding of the kinetics of neuroinflammation and its relationship to the hallmarks of the disease. Both are important for the development of future therapeutic modalities and for quantifying the efficacy of future disease-modifying treatments.

The specific PKR inhibitor C16 prevents apoptosis and IL-1β production in an acute excitotoxic rat model with a neuroinflammatory component

The double-stranded RNA-dependent protein kinase (PKR), an apoptotic inducer, regulates much pro-inflammatory cytokine production. The purpose of this study was to evaluate in vivo the effects of the specific PKR inhibitor C16 in the striatum in an acute excitotoxic rat model with an important neuroinflammatory component. Inflammation was induced by unilateral striatal injection of quinolinic acid (QA) in 10-week-old normotensive rats. Animals were separated into groups receiving either vehicle or C16 for both sham and QA rats. The effects were assessed in ipsi- and contralateral striata by immunoblotting for PKR activation, by Luminex assay for cytokine levels and by immunofluorescent staining for cleaved caspase-3 to detect neuronal apoptosis. The highest dose of C16 (600μg/kg; C16-2) in QA rats reduced expression of the active catalytic domain of the PKR vs. that in vehicle-injected QA rats. A robust increase of IL-1β levels on the contralateral side of QA rats was prevented by C16-2 (97% inhibition). Macroscopic and microscopic observation of cerebral tissue (Hematoxylin & Eosin staining) revealed that tissue integrity was more preserved with C16-2 treatment than its vehicle in QA rats. Furthermore, C16-2 treatment decreased by 47% the neuronal loss and by 37% the number of positive cleaved caspase-3 neurons induced by QA injection. In conclusion, C16 prevented not only the PKR-induced neuronal loss but also the inflammatory response in this acute excitotoxic in vivo model, highlighting its promising neuroprotective properties to rescue acute brain lesions.

Prevention of the β-amyloid peptide-induced inflammatory process by inhibition of double-stranded RNA-dependent protein kinase in primary murine mixed co-cultures

Background

Inflammation may be involved in the pathogenesis of Alzheimer's disease (AD). There has been little success with anti-inflammatory drugs in AD, while the promise of anti-inflammatory treatment is more evident in experimental models. A new anti-inflammatory strategy requires a better understanding of molecular mechanisms. Among the plethora of signaling pathways activated by β-amyloid (Aβ) peptides, the nuclear factor-kappa B (NF-κB) pathway could be an interesting target. In virus-infected cells, double-stranded RNA-dependent protein kinase (PKR) controls the NF-κB signaling pathway. It is well-known that PKR is activated in AD. This led us to study the effect of a specific inhibitor of PKR on the Aβ42-induced inflammatory response in primary mixed murine co-cultures, allowing interactions between neurons, astrocytes and microglia.

Methods

Primary mixed murine co-cultures were prepared in three steps: a primary culture of astrocytes and microglia for 14 days, then a primary culture of neurons and astrocytes which were cultured with microglia purified from the first culture. Before exposure to Aβ neurotoxicity (72 h), co-cultures were treated with compound C16, a specific inhibitor of PKR. Levels of tumor necrosis factor-α (TNFα), interleukin (IL)-1β, and IL-6 were assessed by ELISA. Levels of P_T451-PKR and activation of IκB, NF-κB and caspase-3 were assessed by western blotting. Apoptosis was also followed using annexin V-FITC immunostaining kit. Subcellular distribution of P_T451-PKR was assessed by confocal immunofluorescence and morphological structure of cells by scanning electron microscopy. Data were analysed using one-way ANOVA followed by a Newman-Keuls' post hoc test

Results

In these co-cultures, PKR inhibition prevented Aβ42-induced activation of IκB and NF-κB, strongly decreased production and release of tumor necrosis factor (TNFα) and interleukin (IL)-1β, and limited apoptosis.

Conclusion

In spite of the complexity of the innate immune response, PKR inhibition could be an interesting anti-inflammatory strategy in AD.

Novel aspects on the contribution of T cells and dendritic cells in the pathogenesis of myositis

This review focuses on recent advances and new hypothesis in the understanding of the T and dendritic cells contribution to the pathogenesis of idiopathic inflammatory myopathies (IIMs), especially polymyositis (PM) and dermatomyositis (DM). The new data show that non-specific amplification of muscle inflammation by T lymphocyte and dendritic cells may result from the local production of cytokines and chemokines. Synergistic interactions between these factors explain some of the clinical features. The potent role of these molecules suggests their potential for therapeutic manipulation using specific inhibitors.

Activated double-stranded RNA-dependent protein kinase and neuronal death in models of Alzheimer's disease

Neuronal death is a pathological hallmark of Alzheimer's disease. We have shown previously that phosphorylated double-stranded RNA-dependent protein kinase is present in degenerating hippocampal neurons and in senile plaques of Alzheimer's disease brains and that genetically down-regulating double-stranded RNA-dependent protein kinase activity protects against in vitro beta-amyloid peptide neurotoxicity. In this report, we showed that two double-stranded RNA-dependent protein kinase blockers attenuate, in human neuroblastoma cells, beta-amyloid peptide toxicity evaluated by caspase 3 assessment. In addition, we have used the newly engineered APP(SL)/presenilin 1 knock-in transgenic mice, which display a severe neuronal loss in hippocampal regions, to analyze the activation of double-stranded RNA-dependent protein kinase. Western blots revealed the increased levels of activated double-stranded RNA-dependent protein kinase and the inhibition of eukaryotic initiation factor 2 alpha activity in the brains of these double transgenic mice. Phosphorylated RNA-dependent protein kinase-like endoplasmic reticulum-resident kinase was also increased in the brains of these mice. The levels of activated double-stranded RNA-dependent protein kinase were also increased in the brains of patients with Alzheimer's disease. At 3, 6 and 12 months, hippocampal neurons display double stranded RNA-dependent protein kinase labelings in both the nucleus and the cytoplasm. Confocal microscopy showed that almost constantly activated double-stranded RNA-dependent protein kinase co-localized with DNA strand breaks in apoptotic nuclei of CA1 hippocampal neurons. Taken together these results demonstrate that double-stranded RNA-dependent protein kinase is associated with neurodegeneration in APP(SL)/presenilin 1 knock-in mice and could represent a new therapeutic target for neuroprotection.

Confirmation and fine mapping of the chromosome 1 alcohol dependence risk locus

Two previous large genetic linkage studies in the US population have implicated an area in chromosome 1p to contain a susceptibility gene for alcohol dependence. The 1-LOD support interval of the linkage signal spans about 30 cM and contains >30000000 DNA base pairs (bp) and 700 predicted genes. In order to reduce the size of the candidate area and potentially identify novel candidate genes within this region, we fine-mapped this area using closely spaced short tandem repeat (STR) markers and the transmission disequilibrium test (TDT) in small nuclear families. The subjects were 87 European-American families including one or more alcohol-dependent offspring (93 children and 174 parents). The initial marker set consisted of 30 STR markers, spanning the Marshfield map interval between 101.48 and 130.73 cM. Using the TDTPHASE program, we identified three markers in the distal part of this region (125-126 cM), which showed evidence of transmission disequilibrium. On the basis of this result, an additional 12 STR markers were genotyped in this region; some of these markers provided additional evidence for linkage disequilibrium. The strongest evidence for transmission disequilibrium was obtained at the marker D1S406 (P=0.005, 126.16 cM), with supporting evidence from three neighboring STR markers D1S424 (126.16 cM, P=0.01), D1S2804 (126.16 cM, P=0.04), and D1S2776 (126.16 cM, P=0.02), which are all located within a <350000 bp interval. These findings suggest that a gene (or genes) causing susceptibility to alcohol dependence resides near location 126.16 cM on chromosome 1. In addition, these results provide independent confirmation of the linkage finding regarding the identification of at least one gene in this region increasing the risk for alcohol dependence.

Interleukin-17 increases the effects of IL-1 beta on muscle cells: arguments for the role of T cells in the pathogenesis of myositis

We studied the production of interleukin (IL)-6 and CCL20/macrophage inflammatory protein-3 alpha (MIP-3 alpha) by human myoblasts and muscle samples in response to IL-17 alone or in combination with IL-1 beta. Both IL-17 and IL-1 beta induced IL-6 production by normal myoblasts and muscle samples. IL-17 had no effect on CCL20 production by myoblasts. Combination of IL-17 and IL-1 beta further increased IL-6 and CCL20 production by muscle samples but not that of CK. IL-17 induced also HLA class I, C-Fos, nuclear factor kappa B (NF-kappa B) and C-Jun expression by myoblasts but not that of HLA class II, CD40, vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1). Finally, immunostaining of dermatomyositis (DM) and polymyositis (PM) muscle biopsies showed IL-17 and CCL20 expression. Our study shows that low levels of cytokines produced by T cells (IL-17) and monocytes (IL-1 beta) can act in combination on skeletal myoblasts and muscle tissue.

The clinical importance of variation within the HLA-Bw4 complex

BACKGROUND

Antibody screening of a patient with a failed renal transplant showed positive reactions with most, but not all HLA-Bw4-associated B-locus antigens. However, the patient's serological HLA class I type suggested the presence of HLA-Bw4.

METHODS

Standard molecular techniques were used to re-type the patient and donor. ELISA antibody screening helped determine the patient's antibody specificity.

RESULTS

The patient's type was HLA-B*1402,4703;Bw6 and the donor HLA-B*4703,51011;Bw4,6. Analysis of ELISA results identified three amino acids (positions 77,80,81) as the most likely epitope recognised by the patient's serum. These corresponded to HLA-B*51011 amino acid mismatches, explaining the lymphocytotoxic reactivity pattern. This epitope is located on a subgroup of the HLA-Bw4 antigen suggesting anti-Bw4 was not a sufficient description of this antibody.

CONCLUSIONS

This report identifies an antibody to a sub-group of the Bw4 public specificity and also confirms the need for sequence-level analysis in the tissue-typing laboratory to determine future unacceptable mismatches.

Enhancing effect of IL-1, IL-17, and TNF-alpha on macrophage inflammatory protein-3alpha production in rheumatoid arthritis: regulation by soluble receptors and Th2 cytokines

Macrophage inflammatory protein (MIP)-3alpha is a chemokine involved in the migration of T cells and immature dendritic cells. To study the contribution of proinflammatory cytokines and chemokines to the recruitment of these cells in rheumatoid arthritis (RA) synovium, we looked at the effects of the monocyte-derived cytokines IL-1beta and TNF-alpha and the T cell-derived cytokine IL-17 on MIP-3alpha production by RA synoviocytes. Addition of IL-1beta, IL-17, and TNF-alpha induced MIP-3alpha production in a dose-dependent manner. At optimal concentrations, IL-1beta (100 pg/ml) was much more potent than IL-17 (100 ng/ml) and TNF-alpha (100 ng/ml). When combined at lower concentrations, a synergistic effect was observed. Conversely, the anti-inflammatory cytokines IL-4 and IL-13 inhibited MIP-3alpha production by activated synoviocytes, but IL-10 had no effect. Synovium explants produced higher levels of MIP-3alpha in RA than osteoarthritis synovium. MIP-3alpha-producing cells were located in the lining layer and perivascular infiltrates in close association with CD1a immature dendritic cells. Addition of exogenous IL-17 or IL-1beta to synovium explants increased MIP-3alpha production. Conversely, specific soluble receptors for IL-1beta, IL-17, and TNF-alpha inhibited MIP-3alpha production to various degrees, but 95% inhibition was obtained only when the three receptors were combined. Similar optimal inhibition was also obtained with IL-4, but IL-13 and IL-10 were less active. These findings indicate that interactions between monocyte and Th1 cell-derived cytokines contribute to the recruitment of T cells and dendritic cells by enhancing the production of MIP-3alpha by synoviocytes. The inhibitory effect observed with cytokine-specific inhibitors and Th2 cytokines may have therapeutic applications.

Impairment of the neuronal dopamine transporter activity in MPP(+)-treated rat was not prevented by treatments with nitric oxide synthase or poly(ADP-ribose) polymerase inhibitors

The neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) causes, via its metabolite MPP(+), damages of the nigrostriatal dopaminergic pathway, similar to those observed in Parkinson's disease. An intranigral injection of 10 microg MPP(+) in rat induced a decrease of about 30% of the neuronal dopamine transporter (DAT) activity 21 days after lesion. Based on the hypothesis that MPTP/MPP(+) neurotoxicity involves the nitric oxide (NO) production and/or an activation of poly(ADP-ribose) polymerase (PARP), we investigated the preventive effects of a treatment either with L-Name, a NO synthase (NOS) inhibitor or 3-aminobenzamide, a PARP inhibitor on the reduction of dopamine uptake induced by MPP(+). Rats received a daily injection i.p. of 50 mg/kg L-Name or 10 mg/kg 3-aminobenzamide 3 days before and during 21 days after the MPP(+) lesion. The results showed that inhibitors of NOS and PARP did not prevent the alteration of DAT activity induced by 10 microg MPP(+), indicating that NO and PARP were not involved in the biochemical cascade leading to the inhibition of rat DAT activity by MPP(+) in our experimental conditions.

Linkage genome scan for loci predisposing to panic disorder or agoraphobia

We conducted a 10 cM linkage genome scan in a set of 20 American pedigrees (153 subjects), ascertained through probands with panic disorder (PD). Several anxiety disorders segregate in these families; they were diagnosed on the basis of Schedule for Affective Disorders and Schizophrenia interview. In this article, we describe results for panic disorder and agoraphobia, which are closely related, common, heritable anxiety disorders. This is the first complete linkage genome scan for agoraphobia and the third for PD. A total of 407 markers (389 autosomal, 18 X chromosome) were genotyped. Multipoint LOD score and NPL analysis were completed using GENEHUNTER2. For PD, two genomic regions meet criteria for suggestive linkage. One of these regions is on chromosome 1 (LOD score = 2.04). This region coincides with a region that generated a LOD score of 1.1 in a previous genome scan by Crowe et al. [2001: Am J Med Genet (Neuropsychiatr Genet) 105:105-109]. The other (LOD score = 2.01) is located on chromosome 11p and occurs at marker CCKBR, one of eight candidate genes examined. For agoraphobia, the most promising potential linkage was on chromosome 3 (NPL score = 2.75; P = 0.005). This was accounted for primarily by a single family that by itself generated an NPL score of 10.01 (P = 0.0039) and a LOD score of 2.10. These results provide initial evidence for a genetic locus on chromosome 3 that contributes to risk for agoraphobia. They also support suggestive linkage to two risk loci for panic disorder. Additional potential loci were identified with lesser statistical support; several of these were consistent with previously reported panic disorder linkage results. Overall, the results presented here suggest that PD and agoraphobia are complex traits that share some, but not all, of their susceptibility loci. Published 2001 Wiley-Liss, Inc.

A new in vitro approach for investigating the MPTP effect on DA uptake

Previous studies have shown that dopamine (DA) uptake was decreased after preincubation of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or 1-methyl-4-phenylpyridinium (MPP(+)) in in vitro slice and synaptosome models. The present study, conducted with and without preincubation, attempted to determine whether inhibition results from a direct effect of neurotoxins on neuronal DA transporter or from an alteration of the transporter secondary to other toxic events. DA uptake was inhibited about 50% in the presence of MPTP+O(2) or MPP(+) (0.1, 1 and 5 mM) in rat striatal slices and synaptosomes. Such inhibition was obtained in synaptosomes preincubated for 150 min with MPP(+) and then washed. Inhibition of DA uptake was lower in slices preincubated with MPTP (5 mM)+O(2) and then washed (30%). Experiments in synaptosomes prepared from slices preincubated with MPTP or MPP(+) showed greater inhibition of DA uptake with MPTP. The results suggest that the inhibition of DA uptake in vitro by MPTP or MPP(+) results initially from a direct effect on the transporter during its penetration in nerve endings and subsequently from a transporter alteration related to toxic events. Thus, the preincubation of striatal slices followed by DA uptake measurement in synaptosomes would appear to be a good in vitro model for studying the dopaminergic toxicity of MPTP.

Modulation of the neuronal dopamine transporter activity by the metabotropic glutamate receptor mGluR5 in rat striatal synaptosomes through phosphorylation mediated processes

There is considerable evidence that the activity of the neuronal dopamine transporter (DAT) is dynamically regulated and a putative implication of its phosphorylation in this process has been proposed. However, there is little information available regarding the nature of physiological stimuli that contribute to the endogenous control of the DAT function. Based on the close relationship between glutamatergic and dopaminergic systems in the striatum, we investigated the modulation of the DAT activity by metabotropic glutamate receptors (mGluRs). Short-term incubations of rat striatal synaptosomes with micromolar concentrations of the group I mGluR selective agonist (S)-3,5-dihydroxyphenylglycine were found to significantly decrease the DAT capacity and efficiency. This alteration was completely prevented by a highly selective mGluR5 antagonist, 2-methyl-6-(phenylethynyl)pyridine hydrochloride (MPEP). The effect of (S)-3,5-dihydroxyphenylglycine was also inhibited by staurosporine and by selective inhibitors of protein kinase C and calcium calmodulin-dependent protein kinase II. Co-application of okadaic acid prolonged the transient effect of the agonist, supporting a critical role for phosphorylation in the modulation of the DAT activity by mGluRs. In conclusion, we propose that striatal mGluR5 contribute to the control of the DAT activity through concomitant activation of both protein kinase C and calcium calmodulin-dependent protein kinase II.

Cost of linkage versus association methods

Identifying genetic factors that influence disease risk is a major goal in genetic epidemiology. In the past, for disease with relatively simple etiology, genetic linkage methods have been highly effective for this purpose. However, as we begin to study more complex diseases and disorders for which each specific genetic factor may play a minor role in causation, the relative values of genetic linkage methods that do not require linkage disequilibrium versus association-based methods that do require linkage disequilibrium must be evaluated. Here, we compare the cost-effectiveness of linkage and association methods for identifying genetic factors for a quantitative trait locus that explains 10% of interindividual variability. We find that the choice of analytical scheme depends upon the degree of disequilibrium in the population. Because this parameter has not been adequately assessed, planning association studies is currently difficult.

Increased dopamine uptake in striatal synaptosomes after treatment of rats with amantadine

The aim of the present study was to investigate the effect of short- and long-term treatments with amantadine on the activity of the neuronal dopamine transporter (DAT) in the rat striatum. For this purpose, the [3H]dopamine uptake was measured in striatal synaptosomes prepared from rats treated for 2, 7 and 14 days with amantadine (40 mg/kg; i.p.). After 7 days of treatment, amantadine increased the apparent V(max) by 30% without modification of the apparent K(m) of dopamine uptake whereas no change in these parameters was observed after 2 and 14 days treatment. Binding assays conducted with [3H]GBR-12935 on membranes prepared from animals treated with amantadine revealed no difference in the density and the affinity of striatal DAT binding sites as compared to control. This indicates that the increased dopamine uptake was not reflecting a modification at the level of the DAT expression. The activity of the DAT is regulated by phosphorylation and one may propose that ionotropic glutamate receptors present on presynaptic terminals directly modulate this phosphorylation. An indirect mechanism would involve presynaptic dopamine receptors that control the activity of the DAT in response to the increased dopamine concentration in the synaptic cleft.

Transfer of telemedical support to Cornwall from a national telemedicine network during a solar eclipse

During late 1998 and early 1999, planning officers in Cornwall predicted a huge increase in summer visitors to the county to observe the August solar eclipse. There was the possibility that a mass gathering in Cornwall could overload existing arrangements for handling accident and emergency patients. We therefore set up a telemedicine system to support the county's minor injury units (MIUs) from hospitals throughout the UK. Six main hospital accident and emergency departments outside Cornwall with existing links to their own MIUs were twinned with 10 of the 11 MIUs in Cornwall before the expected date of the gathering. The network was live for nine days, starting four days before the eclipse, and 2045 patients were seen in the 10 MIUs. There were 93 telemedicine calls from the 10 MIUs, involving 91 patients. Overall, 4.6% of the patients required a telemedicine consultation. Fifty-seven calls were made during working hours. Thirty-four patients were referred for further management, of whom 18 were referred on the same day. The transfer of telemedical support to a national network was successful.

Interaction partners of Dlk/ZIP kinase: co-expression of Dlk/ZIP kinase and Par-4 results in cytoplasmic retention and apoptosis

Dlk/ZIP kinase is a newly discovered serine/threonine kinase which, due to its homology to DAP kinase, was named DAP like kinase, Dlk. This kinase is tightly associated with nuclear structures, it undergoes extensive autophosphorylation and phosphorylates myosin light chain and core histones H3, H2A and H4 in vitro. Moreover, it possesses a leucine zipper which mediates interaction with transcription factor ATF-4, therefore it was called ZIP kinase. We employed the yeast two-hybrid system to identify interaction partners of Dlk that might serve as regulators or targets. Besides ATF-4 and others we found Par-4, a modulator of transcription factor WT1 and mediator of apoptosis. Complex formation between Dlk and Par-4 was confirmed by GST pull-down experiments and kinase reactions in vitro and coexpression experiments in vivo. The interaction domain within Dlk was mapped to an arginine-rich region between residues 338 - 417, rather than to the leucine zipper. Strikingly, coexpression of Dlk and Par-4 lead to relocation of Dlk from the nucleus to the cytoplasm, particularly to actin filaments. These interactions provoked a dramatic reorganization of the cytoskeleton and morphological symptoms of apoptosis, thus suggesting a functional relationship between Dlk and Par-4 in the control of apoptosis.