Effects of particulate matters on inflammatory markers in the general adult population

Summary: Particulate air pollution is associated with increased cardiovascular risk. The induction of systemic inflammation following particle inhalation represents a plausible mechanistic pathway. The purpose of this study was to assess the associations of short-term exposure to ambient particulate matters of aerodynamic diameter less than 10 μm (PM10) with circulating inflammatory markers in 6183 adults in Lausanne, Switzerland. The results show that short-term exposure to PM10 was associated with higher levels of circulating IL-6 and TNF-α. The positive association of PM10 with markers of systemic inflammation materializes the link between air pollution and cardiovascular risk. Background: Variations in short-term exposure to particulate matters (PM) have been repeatedly associated with daily all-cause mortality. Particle-induced inflammation has been postulated to be one of the important mechanisms for increased cardiovascular risk. Experimental in-vitro, in-vivo and controlled human studies suggest that interleukin 6 (IL-6) and tumor-necrosis-factor alpha (TNF-α) could represent key mediators of the inflammatory response to PM. The associations of short-term exposure to ambient PM with circulating inflammatory markers have been inconsistent in studies including specific subgroups so far. The epidemiological evidence linking short-term exposure to ambient PM and systemic inflammation in the general population is scarce. So far, large-scale population-based studies have not explored important inflammatory markers such as IL-6, IL-1β or TNF-α. We therefore analyzed the associations between short-term exposure to ambient PM10 and circulating levels of high-sensitive CRP (hs-CRP), IL-6, IL-1β and TNF-α in the population-based CoLaus study. Objectives: To assess the associations of short-term exposure to ambient particulate matters of aerodynamic diameter less than 10 μm (PM10) with circulating inflammatory markers, including hs-CRP, IL-6, IL-1β and TNF-α, in adults aged 35 to 75 years from the general population. Methodology: All study subjects were participants to the CoLaus study (www.colaus.ch) and the baseline examination was carried out from 2003 to 2006. Overall, 6184 participants were included. For the present analysis, 6183 participants had data on at least one of the four measured circulating inflammatory markers. The monitoring data was obtained from the website of Swiss National Air Pollution Monitoring Network (NABEL). We analyzed data on PM10 as well as outside air temperature, pressure and humidity. Hourly concentrations of PM10 were collected from 1 January 2003 to 31 December 2006. Robust linear regression (PROC ROBUSTREG) was used to evaluate the relationship between cytokine inflammatory and PM10. We adjusted all analyses for age, sex, body mass index, smoking status, alcohol consumption, diabetes status, hypertension status, education levels, zip code, and statin intake. All data were adjusted for the effects of weather by including temperature, barometric pressure, and season as covariates in the adjusted models. We performed simple and multiple logistic regression analyses. Descriptive statistical analysis used the Wilcoxon rank sum test (for medians). All data analyses were performed using SAS software (version 9.2; SAS Institute Inc., Cary, NC, USA), and a two-sided significance level of 5% was used. Results: PM10 levels averaged over 24 hours were significantly and positively associated with continuous IL-6 and TNF-α levels, in the whole study population both in unadjusted and adjusted analyses. For each cytokine, there was a similar seasonal pattern, with wider confidence intervals in summer than during the other seasons, which might partly be due to the smaller number of participants examined in summer. The associations of PM10 with IL-6 and TNF-α were also found after having dichotomized these cytokines into high versus low levels, which suggests that the associations of PM10 with the continuous cytokine levels are very robust to any distributional assumption and to potential outlier values. In contrast with what we observed for continuous IL-1β levels, high PM10 levels were significantly associated with high IL-1β. PM10 was significantly associated with IL-6 and TNF-α in men, but with TNF-α only in women. However, there was no significant statistical interaction between PM10 and sex. For IL-6 and TNF-α, the associations tended to be stronger in younger people, with a significant interaction between PM10 and age groups for IL-6. PM10 was significantly associated with IL-6 and TNF-α in the healthy group and also in the "non-healthy" group, although the statistical interaction between healthy status and PM10 was not significant. Conclusion: In summary, we found significant independent positive associations of short-term exposure to PM10 with circulating levels of IL-6 and TNF-α in the adult population of Lausanne. Our findings strongly support the idea that short-term exposure to PM10 is sufficient to induce systemic inflammation on a broad scale in the general population. From a public health perspective, the reported association of elevated inflammatory cytokines with short-term exposure to PM10 in a city with relatively clean air such as Lausanne supports the importance of limiting urban air pollution levels.

Multisystem Langerhans' cell histiocytosis (Hand-Schüller-Christian disease) in an adult: a case report and review of the literature.

Langerhans' cell histiocytosis (LCH) is a rare and enigmatic clonal disorder that affects mainly children. It is characterized by single or multiple granulomatous mass lesions composed of cells with the Langerhans' cell phenotype. Clinical presentation and behavior are heterogeneous and can range from a solitary lytic bone lesion (i.e., eosinophilic granuloma) with a favorable course to a fatal disseminated leukaemia-like form, with a wide spectrum of intermediate clinical presentations between these two extremes. Although LCH typically involves the bone, lesions can be found in almost all organs. We are reporting the case of a multisystem LCH in a 47-year-old patient who presented with a panhypopituitarism and diabetes insipidus, and who, 5 years later, developed mandibular, mastoid and femoral lesions. The final diagnosis of LCH was made on mandibular biopsy.

Therapeutic concepts in adult and paediatric eosinophilic oesophagitis.

Eosinophilic oesophagitis (EoE) was first described in the early 1990s. Although initially reported to be a rare entity, EoE has rapidly become a regularly diagnosed disease with a prevalence of approximately 1 in 2,000 individuals in the USA and Europe. The disease is characterized by a combination of oesophageal dysfunction and predominant eosinophilic infiltration of the oesophageal tissue. At diagnosis, other diseases that can be associated with oesophageal eosinophilic infiltration must be ruled out. Children with EoE present with a wide variety of symptoms, whereas adults mostly present with dysphagia for solid food and chest pain. Histologic features of EoE resemble those of T-helper type 2 inflammation. Endoscopy should be carried out to establish the diagnosis, but endoscopic abnormalities are not pathognomonic for EoE and the examination might not show histologic abnormality. Treatment modalities for EoE include drugs (corticosteroids, PPIs, antiallergic and biologic agents), hypoallergenic diets and oesophageal dilatation for strictures that are unresponsive to medical therapy. Unresolved eosinophilic inflammation leads to the formation of oesophageal strictures, which probably increase the risk of food bolus impactions. To date, long-term strategies for the therapeutic management of this chronic inflammatory disease remain poorly defined.

Alcohol consumption and binge drinking in young adult childhood cancer survivors.

BACKGROUND: This study compared frequency of alcohol consumption and binge drinking between young adult childhood cancer survivors and the general population in Switzerland, and assessed its socio-demographic and clinical determinants. PROCEDURE: Childhood cancer survivors aged <16 years when diagnosed 1976-2003, who had survived >5 years and were currently aged 20-40 years received a postal questionnaire. Reported frequency of alcohol use and of binge drinking were compared to the Swiss Health Survey, a representative general population survey. Determinants of frequent alcohol consumption and binge drinking were assessed in a multivariable logistic regression. RESULTS: Of 1,697 eligible survivors, 1,447 could be contacted and 1,049 (73%) responded. Survivors reported more often than controls to consume alcohol frequently (OR = 1.7; 95%CI = 1.3-2.1) and to engage in binge drinking (OR = 2.9; 95%CI = 2.3-3.8). Peak frequency of binge drinking in males occurred at age 24-26 years in survivors, compared to age 18-20 in the general population. Socio-demographic factors (male gender, high educational attainment, French and Italian speaking, and migration background from Northern European countries) were most strongly associated with alcohol consumption patterns among both survivors and controls. CONCLUSIONS: The high frequency of alcohol consumption found in this study is a matter of concern. Our data suggest that survivors should be better informed on the health effects of alcohol consumption during routine follow-up, and that such counseling should be included in clinical guidelines. Future research should study motives of alcohol consumption among survivors to allow development of targeted health interventions for this vulnerable group.

Neurophysiologic and proteomic investigations of experience-dependent plasticity in the somatosensory cortex of the adult mouse following chronic whisker stimulation

RESUME Les follicules des vibrisses des rongeurs sont représentés sous la forme d'une carte topographique dans le cortex à tonneaux. Lorsque un groupe de vibrisses est coupé pendant plusieurs jours chez un rongeur adulte, en laissant les autres vibrisses intactes, le champ réceptif des neurones du cortex à tonneaux est modifié, ce qui démontre que les cartes corticales sont plastiques. Dans notre étude, une expérience sensorielle a été induite chez une souris adulte se comportant librement en stimulant chroniquement une de ses vibrisses pendant 24h. Par une analyse des potentiels de champ locaux, nous démontrons que les caractéristiques spatiotemporelles du flux d'excitation évoqué par la vibrisse principale (VP) dans la colonne corticale correspondante à la vibrisse stimulée n'est pas altéré. Par contre, l'enregistrement des potentiels d'actions d'un total de 1041 neurones à travers le cortex à tonneaux révèlent plusieurs modifications de l'activité neuronale. L'activité spontanée ainsi que la réponse évoquée par la VP sont déprimées dans la colonne corticale stimulée (nombre moyen de potentiels d'action évoqués par la VP diminue de 25 % et 36% dans la couche IV et les couches II&III). La réponse des neurones à la vibrisse stimulée diminue également dans les colonnes corticales adjacentes, «non-stimulées». La dépression de l'activité spontanée et de la réponse à la VP est localisée à la colonne corticale stimulée. Dans le tonneau stimulé, la première partie de la réponse à la VP n'est pas affaiblie, démontrant que la dépression de la réponse n'est pas due à un phénomène de plasticité sous-corticale ou thalamocorticale. La stimulation chronique d'une vibrisse entraîne une augmentation du nombre de synapses GABAergiques dans la couche IV du tonneau correspondant (Knott et al, 2002). Dès lors, nos résultats suggèrent qu'une augmentation de l'inhibition dans le tonneau stimulé serait à l'origine de la diminution des potentiels d'action évoqués par la vibrisse stimulée et en conséquence de l'amplitude du flux d'excitation vers les couches II&III puis vers les colonnes corticales adjacentes. Toutes les réponses des neurones du tonneau stimulé ne sont pas déprimées. Les réponses des neurones à la vibrisse voisine caudale à VP diminuent dans la couche IV (42%) et dans les couches II&III (52%) mais pas les réponses aux 7 autres vibrisses voisines. Les entrées synaptiques en provenance de la vibrisse caudale pourraient avoir été spécifiquement déprimées en raison d'une décorrélation prolongée entre l'activité évoquée dans les chemins sensoriels relatifs à la vibrisse stimulée et à la vibrisse caudale, spécificité qui découlerait du fait que, parmi les vibrisses voisines à la VP, la vibrisse caudale génère les réponses les plus fortes dans la colonne corticale. Quatre jours après l'arrêt de la stimulation, l'activité neuronale n'est plus déprimée; au contraire, nous observons une potentiation des réponses à la VP dans la couche IV de la colonne corticale stimulée. De plus, nous montrons que l'expression des protéines GLT-1 et GLAST, deux transporteurs astrocytaires du glutamate, est augmentée de ~2.5 fois dans la colonne corticale stimulée, indiquant l'existence d'une «plasticité gliale» et suggérant que les cellules gliales participent activement à l'adaptation du cerveau à l'expérience. ABSTRACT In the barrel cortex, mystacial whisker follicles are represented in the form of a topographie map. The selective removal of a set of whiskers while sparing others for several days in an adult rodent alters receptive field of barrel cortex neurons, demonstrating experience-dependent plasticity of cortical maps. Here sensory experience was altered by chronic stimulation of a whisker for a 24h period in a freely behaving adult mouse. By means of an evoked local field potential analysis, we show that chronic stimulation does not alter the flow of excitation evoked by the principal whisker (PW) in the stimulated barrel column. However, the recording of neuronal firing from a total of 1041 single units throughout the barrel cortex reveals several changes in neuronal activity. Immediately after chronic stimulation, spontaneous activity as well as PW-responses are depressed in the stimulated barrel column (mean number of spikes per PW-deflection decreases by 25% and 36% in layer IV and layers II&III, respectively). Neuronal responses towards the chronically stimulated whisker are also significantly depressed in layers II&III of the adjacent "non-stimulated" barrel' columns. The depression of both spontaneous activity and PW-responses are restricted to the stimulated ban-el column. The earliest time epoch of the PW-response in the stimulated barrel is not depressed, demonstrating that the decrease of cortical responses is not due to subcortical or thalamocortical plasticity. The depression of PW-response in the stimulated barrel correlates with an increase in the number of GABAergic synapses in layer IV (Knott et al., 2002). Therefore, our results suggest that an increase in inhibition within the stimulated barrel may reduce its excitatory output and accordingly the flow of excitation towards layers and the subsequent horizontal spread into adjacent barrel columns. Not all responses of neurons in the stimulated barrel are depressed. Neuronal responses towards the caudal in-row whisker decrease by 42% in layer IV and 52% in layers MM but responses to the other 7 immediate surround whiskers (SWs) are not affected. The synaptic inputs from the SW that elicit the strongest responses in the stimulated barrel may have been specifically depressed following a prolonged period of diminished coherence between neuronal activity evoked in the pathways from the chronically stimulated whisker and from its surrounding in-row whisker. Four days after the cessation of the stimulation, depression of neuronal activity is no longer present; on the contrary, we observe a small but significant potentiation of PW-responses in layer IV of the stimulated barrel column. Moreover we show that the expression of astrocytic glutamate transporters GLT-1 and GLAST proteins were both upregulated by ~2.5 fold in the stimulated barrel column, which indicates that glial cells exhibit experience-dependent functional changes and could actively take part in the adaptation of the cerebral cortex to experience.

Is there an age cutoff to apply adult formulas for GFR estimation in children?

BACKGROUND: Estimation of glomerular filtration rate (eGFR) using a common formula for both adult and pediatric populations is challenging. Using inulin clearances (iGFRs), this study aims to investigate the existence of a precise age cutoff beyond which the Modification of Diet in Renal Disease (MDRD), the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), or the Cockroft-Gault (CG) formulas, can be applied with acceptable precision. Performance of the new Schwartz formula according to age is also evaluated. METHOD: We compared 503 iGFRs for 503 children aged between 33 months and 18 years to eGFRs. To define the most precise age cutoff value for each formula, a circular binary segmentation method analyzing the formulas' bias values according to the children's ages was performed. Bias was defined by the difference between iGFRs and eGFRs. To validate the identified cutoff, 30% accuracy was calculated. RESULTS: For MDRD, CKD-EPI and CG, the best age cutoff was ≥14.3, ≥14.2 and ≤10.8 years, respectively. The lowest mean bias and highest accuracy were -17.11 and 64.7% for MDRD, 27.4 and 51% for CKD-EPI, and 8.31 and 77.2% for CG. The Schwartz formula showed the best performance below the age of 10.9 years. CONCLUSION: For the MDRD and CKD-EPI formulas, the mean bias values decreased with increasing child age and these formulas were more accurate beyond an age cutoff of 14.3 and 14.2 years, respectively. For the CG and Schwartz formulas, the lowest mean bias values and the best accuracies were below an age cutoff of 10.8 and 10.9 years, respectively. Nevertheless, the accuracies of the formulas were still below the National Kidney Foundation Kidney Disease Outcomes Quality Initiative target to be validated in these age groups and, therefore, none of these formulas can be used to estimate GFR in children and adolescent populations.

Semaphorin7A regulates neuroglial plasticity in the adult hypothalamic median eminence.

Reproductive competence in mammals depends on the projection of gonadotropin-releasing hormone (GnRH) neurons to the hypothalamic median eminence (ME) and the timely release of GnRH into the hypothalamic-pituitary-gonadal axis. In adult rodents, GnRH neurons and the specialized glial cells named tanycytes periodically undergo cytoskeletal plasticity. However, the mechanisms that regulate this plasticity are still largely unknown. We demonstrate that Semaphorin7A, expressed by tanycytes, plays a dual role, inducing the retraction of GnRH terminals and promoting their ensheathment by tanycytic end feet via the receptors PlexinC1 and Itgb1, respectively. Moreover, Semaphorin7A expression is regulated during the oestrous cycle by the fluctuating levels of gonadal steroids. Genetic invalidation of Semaphorin7A receptors in mice induces neuronal and glial rearrangements in the ME and abolishes normal oestrous cyclicity and fertility. These results show a role for Semaphorin7A signalling in mediating periodic neuroglial remodelling in the adult ME during the ovarian cycle.

How do gastroenterologists assess overall activity of eosinophilic esophagitis in adult patients?

OBJECTIVES: There is no "gold standard" for assessing disease activity in patients with eosinophilic esophagitis (EoE). We aimed to compare physicians' judgment of EoE activity with patients' judgment of symptom severity. We also aimed to examine the relative contribution of symptoms as well as endoscopic and histologic findings in shaping physicians' judgment of EoE activity. METHODS: Six gastroenterologists (all EoE experts) assessed EoE-associated symptoms in adult patients. Patients completed a symptom instrument and provided global assessment of EoE symptom severity (PatGA) (Likert scale: 0 (inactive) to 10 (most active)). Following esophagogastroduodenoscopy with biopsy sampling, gastroenterologists provided a global assessment of EoE activity (PhysGA) (Likert scale from 0 to 10) based on patient history and endoscopic and histologic findings. Linear regression and analysis of variance was used to quantify the extent to which variations in severity of EoE symptoms and endoscopic and histologic findings explain variations in PhysGA. RESULTS: A total of 149 EoE patients were prospectively included (71.8% male, median age at inclusion 38 years, 71.8% with concomitant allergies). A moderate positive correlation between PhysGA and PatGA (rho=0.442, P<0.001) was observed and the mean difference in the Bland-Altman plot was 1.77. Variations in severity of endoscopic findings, symptoms, and histologic findings alone explained 53%, 49%, and 30%, of the variability in PhysGA, respectively. Together, these findings explained 75% of variability in PhysGA. CONCLUSIONS: Gastroenterologists rate EoE activity mainly on the basis of endoscopic findings and symptoms and, to a lesser extent, on histologic findings.

Est-ce qu'en discuter fait la différence ? Opinions de jeunes adultes atteints de maladies chroniques après avoir été transférés vers des soins pour adultes [Does talking about it make a difference? Opinions of chronically ill young adults after being transferred to adult care].

1) Introduction: pour les jeunes souffrant de maladie chronique, l'objectif de la transition vers les soins pour adultes est d'optimiser leur fonctionnement et leur potentiel. Le but de cette étude pilote était d'évaluer si les jeunes adultes souffrant de maladie chronique jugeaient que le passage vers les soins adultes était plus facile lorsque la question de la transition avait été discutée au préalable avec leur pédiatre. 2) Matériel et méthodes: deux groupes de jeunes adultes atteints de maladie chronique ont été identifiés selon l'existence (n = 70) ou non (n = 22) d'une discussion préalable avec leur pédiatre à propos de la transition vers une prise en charge pour adultes. Ces deux groupes ont été comparés pour des variables démographiques et de santé. Les variables significatives en analyse bivariée ont été incluses dans une régression logistique descendante pas à pas. 3) Résultats: les jeunes adultes qui avaient discuté de la transition étaient significativement plus nombreux à se sentir prêts (72,9 % vs 45,5 %) et accompagnés (58,6 % vs 27,3 %) pour le transfert, à avoir consulté leur spécialiste pour adultes (60 % vs 31,8 %) et à voir leur médecin sans la présence de leurs parents (70 % vs 40,9 %). En analyse multivariée, seuls, le fait de se sentir accompagné (odds ratio ajustée [ORa] : 3,56) et celui d'avoir consulté leur spécialiste pour adultes (ORa : 4,14) étaient significatifs. 4) Conclusions: la préparation des jeunes souffrant de maladie chronique au transfert vers les soins pour adultes semble bénéfique. Cependant, le transfert lui-même n'est qu'une petite partie du concept beaucoup plus large de la transition vers la vie adulte. Une transition bien planifiée doit permettre à ces jeunes adultes d'atteindre tout leur potentiel. INTRODUCTION: The goal of transition in healthcare for young people with chronic illnesses is to maximize their functioning and potential. The purpose of this pilot study was to assess whether young adults with chronic illnesses found that the transition to adult care was easier when the transition was discussed in advance with their pediatric specialist. METHODS: Two groups were created according to whether patients had discussed (n=70) or not (n=22) the transition with their pediatric specialist and compared regarding demographic and health-related variables. All the significant variables at the bivariate level were included in a backward stepwise logistic regression. RESULTS: Youth who had discussed the transition were significantly more likely to feel ready for the transfer (72.9% vs 45.5%) and accompanied (58.6% vs 27. %) during transfer, to have consulted their specialist for adults (60.0% vs 31.8%), and seen their doctor without the presence of their parents (70.0% vs 40.9%). At the multivariate level, only feeling accompanied during transfer (adjusted odds ratio (aOR): 3.56) and having consulted their specialist for adults (aOR: 4.14) remained significant. CONCLUSIONS: Preparing chronically ill youths for transfer to adult care appears to be beneficial for them. However, transfer is only a small part of the much broader transition that is preparation for adult life. A well-planned transition should allow these young people to reach their full potential.

Données actualisées sur la physiopathologie, les phénotypes et les traitements de la maladie de Still de l'adulte [Pathophysiology, subtypes, and treatments of adult-onset Still's disease: An update].

Adult-onset Still's disease is a rare and difficult to diagnose multisystemic disorder considered as a multigenic autoinflammatory syndrome. Its immunopathogenesis seems to be at the crossroads between inflammasomopathies and hemophagocytic lymphohistiocytosis, the most severe manifestation of the disease. According to recent insights in the pathophysiology and thanks to cohort studies and therapeutic trials, two phenotypes of adult-onset Still's disease may be distinguished: a systemic pattern, initially highly symptomatic and with a higher risk to exhibit life-threatening complications such as reactive hemophagocytic lymphohistiocytosis, where interleukin-1 blockade seems to be very effective, a chronic articular pattern, more indolent with arthritis in the foreground and less severe systemic manifestations, which would threat functional outcome and where interleukin-6 blockade seems to be more effective. This review focuses on these data.

Transition aux soins adultes : une vue d'ensemble [Transition to adult care: an overview]

De nos jours, près de 90% des enfants atteints d'une maladie chronique survivent au-delà de l'âge de vingt ans et doivent passer de la pédiatrie aux soins adultes et de l'enfance à l'adolescence et à l'âge adulte. Selon la Society for Adolescent Medicine and Health (SAHM), les objectifs d'une transition organisée et coordonnée aux soins adultes pour les jeunes malades chroniques devraient permettre d'optimiser leur santé et de faciliter la réalisation de leur potentiel maximal.1 En conséquence, bien que le but principal de la transition soit la continuité des soins, elle n'est pas limitée au transfert (le passage de l'information et du patient de la pédiatrie aux soins adultes) mais est beaucoup plus large et inclut la préparation à la vie adulte. Ainsi donc, la transition devrait commencer tôt pendant l'adolescence, finir quand le patient devient un jeune adulte et englober trois parties : une phase de préparation en pédiatrie, une de transfert de la pédiatrie aux soins adultes et une dernière d'engagement aux soins adultes. Nowadays nearly 90% of children with a chronic condition survive to adulthood and must make the transition from pediatric to adult care. This transition must include not only the continuity of care but also the preparation for adult life so that these young people can develop their full potential. Divided into three phases (preparation, transfer and engagement), the transition process should be adapted to adolescents and ensure access to quality care.