Search

International audience; Accumulating evidence indicates that the MDM2 oncoprotein promotes tumorigenesis beyond its canonical negative effects on the p53 tumor suppressor, but these p53-independent functions remain poorly understood. Here, we show that a fraction of endogenous MDM2 is actively imported in mitochondria to control respiration and mitochondrial dynamics independently of p53. Mitochondrial MDM2 represses the transcription of NADH-dehydrogenase 6 (MT-ND6) in vitro and in vivo, impinging on respiratory complex I activity and enhancing mitochondrial ROS production. Recruitment of MDM2 to mitochondria increases during oxidative stress and hypoxia. Accordingly, mice lacking MDM2 in skeletal muscles exhibit higher MT-ND6 levels, enhanced complex I activity, and increased muscular endurance in mild hypoxic conditions. Furthermore, increased mitochondrial MDM2 levels enhance the migratory and invasive properties of cancer cells. Collectively, these data uncover a previously unsuspected function of the MDM2 oncoprotein in mitochondria that play critical roles in skeletal muscle physiology and may contribute to tumor progression.

The influence of socioeconomic status (SES) on access to standard chemotherapy and/or monoclonal antibody therapy, and associated secular trends, relative survival, and excess mortality, among diffuse large B-cell lymphoma (DLBCL) patients is not clear. We conducted a Hong Kong population-based cohort study and identified adult patients with histologically diagnosed DLBCL between 2000 and 2018. We examined the association of SES levels with the odds and the secular trends of receipt of chemotherapy and/or rituximab. Additionally, we estimated the long-term relative survival by SES utilizing Hong Kong life tables. Among 4017 patients with DLBCL, 2363 (58.8%) patients received both chemotherapy and rituximab and 740 (18.4%) patients received chemotherapy alone, while 1612 (40.1%) and 914 (22.8%) patients received no rituximab or chemotherapy, respectively. On multivariable analysis, low SES was associated with lesser use of chemotherapy (odd ratio [OR] 0.44; 95% CI 0.34–0.57) and rituximab (OR 0.41; 95% CI 0.32–0.52). The socioeconomic disparity for either treatment showed no secular trend of change. Additionally, patients with low SES showed increased excess mortality, with a hazard ratio of 2.34 (95% CI 1.67–3.28). Improving survival outcomes for patients with DLBCL requires provision of best available medical care and securing access to treatment regardless of patients’ SES.

The autonomic nervous system is a master regulator of homeostatic processes and stress responses. Sympathetic noradrenergic nerve fibers decrease bone mass, but the role of cholinergic signaling in bone has remained largely unknown. Here, we describe that early postnatally, a subset of sympathetic nerve fibers undergoes an interleukin-6 (IL-6)-induced cholinergic switch upon contacting the bone. A neurotrophic dependency mediated through GDNF-family receptor-α2 (GFRα2) and its ligand, neurturin (NRTN), is established between sympathetic cholinergic fibers and bone-embedded osteocytes, which require cholinergic innervation for their survival and connectivity. Bone-lining osteoprogenitors amplify and propagate cholinergic signals in the bone marrow (BM). Moderate exercise augments trabecular bone partly through an IL-6-dependent expansion of sympathetic cholinergic nerve fibers. Consequently, loss of cholinergic skeletal innervation reduces osteocyte survival and function, causing osteopenia and impaired skeletal adaptation to moderate exercise. These results uncover a cholinergic neuro-osteocyte interface that regulates skeletogenesis and skeletal turnover through bone-anabolic effects., S.G. was supported by the NIH-OXCAM Program and the Gates Cambridge Trust. A.G.G. received fellowships from Ramón Areces and La Caixa Foundations. C.K. was supported by Marie Curie Career Integration grant H2020-MSCA-IF-2015-70841. M.S. and R.S. were supported by DFG, Se 697/7-1 and BMBF through the EnergI consortium TP6. J.V. and J.J.T.-A. were supported by Instituto de Salud Carlos III (PI12/02574), Junta de Andalucia (P12-CTS-2739), and, together with S.M.-F., by Red TerCel (ISCIII-Spanish Cell Therapy Network). S.A. and C.D.B. were supported by Versus Arthritis grant 21156. A.W.M. received funding from Versus Arthritis (21156). P.G.R. and S.G. were supported by the DIR, NIDCR, a part of the IRP, NIH, and DHHS (1ZIADE000380). K.E.S.P. acknowledges the support of the Cambridge NIHR Biomedical Research Centre. This work was supported by core support grants from MRC to the Cambridge Stem Cell Institute; National Health Service Blood and Transplant (United Kingdom), European Union’s Horizon 2020 research (ERC-2014-CoG-648765), MRC-AMED grant MR/V005421/1, and a Programme Foundation Award (C61367/A26670) from Cancer Research UK to S.M.-F. This research was funded in part by the Wellcome Trust (203151/Z/16/Z).

The sympathetic nervous system has been evolutionary selected to respond to stress and activates haematopoietic stem cells via noradrenergic signals. However, the pathways preserving haematopoietic stem cell quiescence and maintenance under proliferative stress remain largely unknown. Here we found that cholinergic signals preserve haematopoietic stem cell quiescence in bone-associated (endosteal) bone marrow niches. Bone marrow cholinergic neural signals increase during stress haematopoiesis and are amplified through cholinergic osteoprogenitors. Lack of cholinergic innervation impairs balanced responses to chemotherapy or irradiation and reduces haematopoietic stem cell quiescence and self-renewal. Cholinergic signals activate α7 nicotinic receptor in bone marrow mesenchymal stromal cells leading to increased CXCL12 expression and haematopoietic stem cell quiescence. Consequently, nicotine exposure increases endosteal haematopoietic stem cell quiescence in vivo and impairs hematopoietic regeneration after haematopoietic stem cell transplantation in mice. In humans, smoking history is associated with delayed normalisation of platelet counts after allogeneic haematopoietic stem cell transplantation. These results suggest that cholinergic signals preserve stem cell quiescence under proliferative stress., The sympathetic nervous system has been shown to respond to stress and activate haematopoietic stem cells. Here they show that cholinergic signals in the bone marrow preserve haematopoietic stem cell quiescence and self-renewal under proliferative stress.

MALF was supported by the Spanish National Health Institute Carlos III (Instituto de Salud Carlos III -ISCIII), Miguel Servet--I Investigator Grant/Award Number CP17/00206--EU--FEDER., Objective We evaluated the temporal trend in gender ratios of first and last authors in the field of oncological research published in major general medical and oncology journals and examined the gender pattern in coauthorship. Design We conducted a retrospective study in PubMed using the R package RISmed. We retrieved original research articles published in four general medical journals and six oncology specialty journals. These journals were selected based on their impact factors and popularity among oncologists. We identified the names of first and last authors from 1 January 2002 to 31 December 2019. The gender of the authors was identified and validated using the Gender API database (https:// gender-​api. com/). Primary and secondary outcome measures The percentages of first and last authors by gender and the gender ratios (male to female) and temporal trends in gender ratios of first and last authors were determined. Results We identified 34 624 research articles, in which 32 452 had the gender of both first and last authors identified. Among these 11 650 (33.6%) had women as the first author and 7908 (22.8%) as the last author, respectively. The proportion of female first and last authors increased from 26.6% and 16.2% in 2002, to 32.9% and 27.5% in 2019, respectively. However, the gender ratio (male to female) of first and last authors decreased by 1.5% and 2.6% per year, respectively, which were statistically significant (first author: incidence rate ratio (IRR) 0.98, 95% CI 0.97 to 1.00; last author: IRR 0.97, 95% CI 0.96 to 0.99). Male first and last authorship was the most common combination. Male–female and female– female pairs increased by 2.0% and 5.0%, respectively (IRR 1.02, 95% CI 1.01 to 1.03 and IRR 1.05, 95% CI 1.04 to 1.06, respectively). Conclusions The continued under-representation of women means that more efforts to address parity for advancement of women in academic oncology are needed., Spanish National Health Institute Carlos III (Instituto de Salud Carlos III -ISCIII) CP17/00206--EU--FEDER

Summary Recent studies highlighted the importance of astrocytes in neuroinflammatory diseases, interacting closely with other CNS cells but also with the immune system. However, due to the difficulty in obtaining human astrocytes, their role in these pathologies is still poorly characterized. Here, we develop a serum-free protocol to differentiate human induced pluripotent stem cells (hiPSCs) into astrocytes. Gene expression and functional assays show that our protocol consistently yields a highly enriched population of resting mature astrocytes across the 13 hiPSC lines differentiated. Using this model, we first highlight the importance of serum-free media for astrocyte culture to generate resting astrocytes. Second, we assess the astrocytic response to IL-1β, TNF-α, and IL-6, all cytokines important in neuroinflammation, such as multiple sclerosis. Our study reveals very specific profiles of reactive astrocytes depending on the triggering stimulus. This model provides ideal conditions for in-depth and unbiased characterization of astrocyte reactivity in neuroinflammatory conditions., Graphical Abstract, Highlights • Human iPSCs are differentiated from blood of control and multiple sclerosis subjects • Functional astrocytes are differentiated from hiPSC in serum-free conditions • In-depth characterization of the effect of serum on astrocyte phenotype • Multiple sclerosis cytokines trigger specific activation profiles in astrocytes, Perriot et al. describe a new protocol to differentiate both resting and reactive astrocytes from human induced pluripotent stem cells in serum-free conditions. They show that astrocytes exhibit highly contrasted responses to serum and to cytokines involved in multiple sclerosis, establishing that this model is suitable to study neuroinflammation.

We explored the role of socioeconomic inequalities in COVID-19 incidence among cancer patients during the first wave of the pandemic. We conducted a case-control study within the UK Biobank cohort linked to the COVID-19 tests results available from 16 March 2020 until 23 August 2020. The main exposure variable was socioeconomic status, assessed using the Townsend Deprivation Index. Among 18,917 participants with an incident malignancy in the UK Biobank cohort, 89 tested positive for COVID-19. The overall COVID-19 incidence was 4.7 cases per 1000 incident cancer patients (95%CI 3.8–5.8). Compared with the least deprived cancer patients, those living in the most deprived areas had an almost three times higher risk of testing positive (RR 2.6, 95%CI 1.1–5.8). Other independent risk factors were ethnic minority background, obesity, unemployment, smoking, and being diagnosed with a haematological cancer for less than five years. A consistent pattern of socioeconomic inequalities in COVID-19 among incident cancer patients in the UK highlights the need to prioritise the cancer patients living in the most deprived areas in vaccination planning. This socio-demographic profiling of vulnerable cancer patients at increased risk of infection can inform prevention strategies and policy improvements for the coming pandemic waves., Spanish National Health Institute Carlos III Miguel Servet-I - CP17/00206-EU-FEDER, EU-FEDER-FIS PI-18/01593

International audience; Introduction - Actionable somatic molecular alterations are found in 15% to 20% of NSCLC in Europe. NSCLC is a tumor observed in patients with germline TP53 variants causing Li-Fraumeni syndrome (LFS), but its somatic molecular profile is unknown. Methods - Retrospective study of clinical and molecular profiles of patients with NSCLC and germline TP53 variants. Results - Among 22 patients with NSCLC and LFS (n = 23 lung tumors), 64% were women, median age was 51 years, 84% were nonsmokers, 73% had adenocarcinoma histological subtype, and 84% were diagnosed with advanced-stage disease. These patients harbored 16 distinct germline TP53 variants; the most common was p.R158H (5/22; three in the same family). Personal and family histories of cancer were reported in 71% and 90% of patients, respectively. In most cases (87%, 13/15), lung cancer was diagnosed with a late onset. Of the 21 tumors analyzed, somatic oncogenic driver mutations were found in 19 of 21 (90%), EGFR mutations in 18 (exon 19 deletion in 12 cases, L858R in three cases, and G719A, exon 20 insertion, and missing mutation subtype, each with one case), and ROS1 fusion in one case. A PI3KCA mutation was concurrently detected at diagnosis in three EGFR exon 19-deleted tumors (3/12). The median overall survival was 37.3 months in 14 patients treated with EGFR inhibitors; seven developed resistance, five (71%) acquired EGFR-T790M mutation, and one had SCLC transformation. Conclusions - Driver oncogenic alterations were observed in 90% of the LFS tumors, mainly EGFR mutations; one ROS1 fusion was also observed. The germline TP53 variants and lung cancer carcinogenesis driven by oncogenic processes need further evaluation.

Non-steroidal anti-inflammatory drugs (NSAIDs), the most commonly prescribed and consumed medicines worldwide, are the main triggers of drug hypersensitivity reactions (DHRs). The underlying mechanisms of NSAID-DHRs may be related to COX-1 inhibition (cross-hypersensitivity reactions, CRs) or to immunological recognition (selective reactions, SRs), being the latter remarkably less studied. SRs include those usually appearing within the first hour after drug intake (single-NSAID-induced urticaria/angioedema or anaphylaxis, SNIUAA), and those usually occurring more than 24 h after (single-NSAID-induced delayed reactions, SNIDR). We have evaluated the largest series of patients with SRs, analyzing the number of episodes and drugs involved, the latency for reaction onset, the clinical entities, among other variables, as well as the value of available diagnostic methods. Globally, pyrazolones and arylpropionics were the most frequent culprits (39.3% and 37.3%, respectively). Pyrazolones were the most frequent triggers in SNIUAA and arylpropionics in SNIDR. Urticaria was the most common clinical entity in SNIUAA (42.4%) followed by anaphylaxis (33.3%); whereas SNIDR induced mostly fixed drug eruption (41.1%) and maculopapular exanthema (32.6%). The percentage of patients diagnosed by clinical history was higher in SNIUAA compared with SNIDR (62.7% versus 35.3%, p = 0.00015), whereas the percentage of those diagnosed by skin tests was higher in SNIDR than in SNIUAA (47.1% versus 22.8%, p = 0.00015). Drug provocation test with the culprit was performed in 67 SNIUAA (14.5%) and in 9 SNIDR (17.6%) patients. Our results may be of interest not only for allergologists but also for other clinicians dealing with these drugs, and can be useful for the correct identification of subjects experiencing DHRs to NSAIDs, and for avoiding mislabeling. Moreover, as NSAIDs are highly consumed worldwide, our results may be of interest for evaluating other populations exposed to these drugs. Yes

Hematopoietic stem cells (HSCs) residing in the bone marrow (BM) accumulate during aging but are functionally impaired. However, the role of HSC-intrinsic and -extrinsic aging mechanisms remains debated. Megakaryocytes promote quiescence of neighboring HSCs. Nonetheless, whether megakaryocyte-HSC interactions change during pathological/natural aging is unclear. Premature aging in Hutchinson-Gilford progeria syndrome recapitulates physiological aging features, but whether these arise from altered stem or niche cells is unknown. Here, we show that the BM microenvironment promotes myelopoiesis in premature/physiological aging. During physiological aging, HSC-supporting niches decrease near bone but expand further from bone. Increased BM noradrenergic innervation promotes β2-adrenergic-receptor(AR)-interleukin-6-dependent megakaryopoiesis. Reduced β3-AR-Nos1 activity correlates with decreased endosteal niches and megakaryocyte apposition to sinusoids. However, chronic treatment of progeroid mice with β3-AR agonist decreases premature myeloid and HSC expansion and restores the proximal association of HSCs to megakaryocytes. Therefore, normal/premature aging of BM niches promotes myeloid expansion and can be improved by targeting the microenvironment., Y.-H.O. received fellowships from Alborada Scholarship (University of Cambridge), Trinity-Henry Barlow Scholarship (University of Cambridge), and R.O.C. Government Scholarship to Study Abroad (GSSA). A.G.G. received fellowships from the Ramón Areces Foundation and the LaCaixa Foundation. C.K. was supported by Marie Curie Career Integration (H2020-MSCA-IF-2015-70841). S.M.-F. was supported by Red TerCel (ISCIII-Spanish Cell Therapy Network). V.A. is supported by grants from the Spanish Ministerio de Economía, Industria y Competitividad (MEIC) with cofunding from the Fondo Europeo de Desarrollo Regional (FEDER, “Una manera de hacer Europa”) (SAF2016-79490-R), the Instituto de Salud Carlos III (AC16/00091 and AC17/00067), the Fundació Marató TV3 (122/C/2015), and the Progeria Research Foundation (Established Investigator Award 2014–52). The CNIC is supported by the Instituto de Salud Carlos III (ISCIII), the Ministerio de Ciencia, Innovación y Universidades (MCIU), and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (SEV-2015-0505). This work was supported by core support grants from the Wellcome Trust and the MRC to the Cambridge Stem Cell Institute, MEIC (SAF-2011-30308), Ramón y Cajal Program Grant (RYC-2009-04703), ConSEPOC-Comunidad de Madrid (S2010/BMD-2542), National Health Service Blood and Transplant (United Kingdom), European Union’s Horizon 2020 research (ERC-2014-CoG-64765 and Marie Curie Career Integration grant FP7-PEOPLE-2011-RG-294096), and a Programme Foundation Award from Cancer Research UK to S.M.-F., who was also supported in part by an International Early Career Scientist grant from the Howard Hughes Medical Institute.

Hematopoietic stem and progenitor cells (HSPCs) and leukocytes circulate between the bone marrow (BM) and peripheral blood following circadian oscillations. Autonomic sympathetic noradrenergic signals have been shown to regulate HSPC and leukocyte trafficking, but the role of the cholinergic branch has remained unexplored. We have investigated the role of the cholinergic nervous system in the regulation of day/night traffic of HSPCs and leukocytes in mice. We show here that the autonomic cholinergic nervous system (including parasympathetic and sympathetic) dually regulates daily migration of HSPCs and leukocytes. At night, central parasympathetic cholinergic signals dampen sympathetic noradrenergic tone and decrease BM egress of HSPCs and leukocytes. However, during the daytime, derepressed sympathetic noradrenergic activity causes predominant BM egress of HSPCs and leukocytes via β3–adrenergic receptor. This egress is locally supported by light-triggered sympathetic cholinergic activity, which inhibits BM vascular cell adhesion and homing. In summary, central (parasympathetic) and local (sympathetic) cholinergic signals regulate day/night oscillations of circulating HSPCs and leukocytes. This study shows how both branches of the autonomic nervous system cooperate to orchestrate daily traffic of HSPCs and leukocytes., This work was supported by core support grants from the Wellcome Trust and the Medical Research Council (MRC) to the Cambridge Stem Cell Institute, the Spanish Ministry of Economy and Competitiveness (SAF-2011-30308), the Pro-CNIC Foundation, Severo Ochoa Center of Excellence award SEV-2015-0505 to CNIC, Ramón y Cajal Program grant RYC-2009-04703, Marie Curie Career Integration grant FP7-PEOPLE-2011-RG-294096, ConSEPOC-Comunidad de Madrid S2010/BMD-2542, Red TerCel (Instituto de Salud Carlos III (ISCIII)-Spanish Cell Therapy Network), National Health Institute Blood and Transplant (United Kingdom), Horizon2020 grant ERC-2014-CoG-64765, and a Cancer Research UK Programme Foundation Award to S.M.-F., who was also supported in part by an International Early Career Scientist grant from the Howard Hughes Medical Institute. A.G.-G. received fellowships from the Ramón Areces and LaCaixa Foundations. C.K. was supported by Marie Curie Career Integration grant H2020-MSCA-IF-2015-708411.

Drug hypersensitivity reactions (DHRs) are unpredictable, complex responses to medicines in predisposed individuals. They represent a major health problem owing to the number of patients affected and the severity of the clinical conditions they can induce. In addition to environmental factors, the underlying mechanisms of DHRs are also influenced by genetic factors, although considerable gaps remain in our knowledge. Therefore, further study of the genetics of DHRs is necessary to shed light on their underlying mechanisms. In this manuscript, we provide an update on the genetic basis of the most frequent types of DHRs, including those mediated by immunological and nonimmunological mechanisms. For the first group, we will focus on immediate reactions to beta-lactam antibiotics, which are associated mainly with the IgE pathway (IL13, IL4R, LGALS3, and NOD2) and antigen presentation (HLA-DRA), and nonimmediate reactions to allopurinol, anticonvulsants, antibiotics, and antiretrovirals, which are often associated with polymorphisms in the HLA system. For the second group, we will focus on nonsteroidal anti-inflammatory drugs, which are mostly associated with genetic variants in enzymes and receptors from the arachidonic acid pathway (eg, ALOX5, ALOX5AP PTGDR, and CYSLTR1). The information provided here will be of interest for medical practitioners from a range of disciplines who come across these reactions in their clinical practice, as well as for allergologists.

Primary graft dysfunction (PGD) after lung transplantation is a multi-factorial syndrome of postoperative lung injury that is similar to the acute respiratory distress syndrome. PGD is a major risk factor for chronic lung allograft dysfunction and perioperative death. Pulmonary surfactant dysfunction is frequently seen in PGD and contributes to respiratory failure. Surfactant is primarily comprised of lipids, of which phosphatidylcholine (PC) species predominate. Dipalmitoylphosphatidylcholine (DPPC) is the most surface-active species that normally represents over half of all airway PC content. Combining electrospray ionisation tandem mass spectrometry with deuterium labelling of Kennedy’s PC synthetic pathway can assess surfactant phospholipid flux, with a molecular specificity that differentiates between lipids with unique functions. This technique was used to quantify perioperative phospholipid metabolic disruption in lung transplantation. The same technique was used in an ex vivo human lung model to isolate the pulmonary contribution to systemic phospholipid metabolism, and evaluate Kennedy pathway integrity during ex vivo lung perfusion (EVLP). Airway DPPC content was severely reduced after transplantation, and was associated with impaired oxygenation. Variations in Kennedy pathway activity were associated with impaired graft function for months after transplantation. Perioperative flux of phospholipids, like DPPC and polyunsaturated PC species, were strong predictors of poor postoperative lung function. Deuterium labelled ex vivo experiments confirmed continued Kennedy pathway dependent surfactant phospholipid synthesis during EVLP, and could represent a protective mechanism against PGD in clinical EVLP. Ex vivo lungs secreted a different phospholipid profile into the perfusate that is enriched with polyunsaturated PC when compared to the airways, providing compelling evidence of the previously hypothesized basolateral phospholipid secretion by the alveolar epithelium. These polyunsaturated PC species are precursors of numerous inflammatory mediators, and could contribute to PGD. Continued investigation of phospholipid flux through the Kennedy pathway could identify novel biomarkers and therapeutic targets in lung transplantation. Open Access

Journal Article; Research Support, Non-U.S. Gov't; Review; Nonsteroidal anti-inflammatory drugs (NSAIDs) are used throughout the world to treat pain and inflammation; however, they can trigger several types of drug hypersensitivity reactions (DHRs) in all age groups. Although most such reactions occur through activation of the leukotriene pathway without specific immunological recognition (cross-intolerance), a significant number of DHRs to NSAIDs are due to immunological mechanisms (selective reactions [SRs]). SRs are thought to be induced by specific IgE antibodies or by T cells. In this manuscript, we focus on SRs, which are of great concern in children and adolescents and comprise a heterogeneous set of clinical pictures ranging from mild entities such as urticaria/angioedema to potentially life-threatening conditions such as Stevens-Johnson syndrome/toxic epidermal necrolysis. Paracetamol and ibuprofen are the most frequent elicitors of IgE-mediated SRs, although pyrazolones have also been implicated. T cell-mediated reactions are infrequent in children but have been associated with ibuprofen, naproxen, and dipyrone. In this review, we analyze the available literature on SRs in children and adolescents, with emphasis on epidemiological data, mechanisms, and drugs involved, as well as on diagnostic procedures. Yes A pesar de su eficacia en el tratamiento del dolor y la inflamación los antiinflamatorios no esteroideos (AINE), los medicamentos de mayor consumo mundial, también son la causa más frecuente de reacciones de hipersensibilidad a fármacos (RHFs) en cualquier tramo de edad. Aunque en muchas de estas reacciones se liberan mediadores inflamatorios en ausencia de reconocimiento inmunológico específico (intolerancia cruzada), un porcentaje considerable de las RHFs a AINE se producen a través de mecanismos inmunológicos (reacciones selectivas, SRs). En éstas participarían anticuerpos IgE específicos o células T. Las SRs son de gran interés en niños y adolescentes e incluyen un conjunto heterogéneo de entidades que comprenden desde manifestaciones clínicas de poca gravedad como la urticaria y el angioedema hasta otras como el síndrome de Stevens-Johnson y la necrolisis epidérmica tóxica, que pueden suponer una amenaza para la vida. En niños el paracetamol y el ibuprofeno son los medicamentos más frecuentemente implicados en las SRs mediadas por IgE aunque también se ha descrito la participación de las pirazolonas. Las reacciones mediadas por linfocitos T son menos frecuentes pero también se han descrito en relación con la administración de ibuprofeno, naproxeno y dipirona. En esta revisión analizaremos la literatura actual sobre las SRs en niños y adolescentes, centrándonos en los datos epidemiológicos, mecanismos y fármacos implicados, así como las pruebas disponibles para su diagnóstico.

Dioxins are pervasive environmental contaminants, to which people are generally exposed through foods of animal origin. Children, before and after birth, are especially susceptible to their toxicity, while the risks to adults seem quite small at current exposure levels. The dioxins bind to a specialised intracellular AH receptor, directly influencing the expression of a substantial number of genes and resulting to variable toxicity depending on the affected species and the strain, as well as the gender and age of the individual. This is exemplified in the dramatic variability of the acute toxicity of the most potent dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin [TCDD]) within one species: H/W rats tolerate over 1000-fold larger doses than the L E strain. On the other hand, one of the few unifying features of acute TCDD intoxication in many laboratory species is a dramatic feed intake reduction and weight loss, termed the wasting syndrome. In this research, the pathophysiological challenge of wasting was tackled in two studies by measuring the effect of one dose of TCDD on hypothalamic mRNA levels of AHR-related proteins and feeding regulatory factors in the resistant H/W and sensitive L E rats. In the latter two experiments the perviously-employed quantitative reverse transcription PCR (RT-qPCR) methodology was refined: A set of stable reference genes for RT-qPCR was first sought, and then the identified reference genes were employed in a study comparing the robustness of various RT and qPCR enzymes and mapping the RT-qPCR variation sources. The small constitutive and TCDD-induced differences in the hypothalamic mRNA expression of some AHR signalling cascade molecules between L E and H/W rat are most likely not causally related to the wasting syndrome. However, a functional AHR signalling cascade appears to be present in the hypothalamus. The lack of any drastic changes in hypothalamic neuropeptide or receptor mRNA following TCDD treatment speak against a severe cytotoxic effect on, or permanent hyperexcitation of the cells. Notably, the employed hypothalamic block sampling might miss expression changes confined to a localised point and omits the various extra-hypothalamic systems in eating regulation. The future studies should thus be targeted to individual nuclei, but to also have a wider scope of eating regulation both inside and outside CNS. The number of genes displaying an acceptable steadiness of expression in the face of lethal TCDD toxicity is small and besides this the RT stability has a strong influence on the usability of the potential reference genes. Furthermore, RT variance markedly exceeds qPCR variance, stressing the importance of replication at the RT level. Finally, linear hierarchical models and Bayesian inference offer an efficient way to build a coherent statistical model of the whole RT-qPCR experiment maximising the use of the data. Dioksiinit ovat kaikkialle maapallolle levinneitä ympäristömyrkkyjä, joille suomalaiset altistuvat lähinnä eräiden Itämeren kalojen välityksellä. Sikiönkehitys ja lapsuus ovat erityisen alttiita dioksiinien myrkkyvaikutuksille, mutta aikuisille niiden aiheuttama vaara nykyisillä altistustasoilla lienee melko pieni. Elimistössä dioksiinit sitoutuvat solunsisäisen AH-reseptoriin, joka aktivoituessaan muuttaa satojen geenien ilmentymistä. Nämä ilmentymismuutokset, ja lopulta haitalliset vaikutukset elimistössä, näyttävät kuitenkin riippuvan eläinlajista, -kannasta iästä ja kudoksesta jossa aktivaatio tapahtuu. Dioksiinien myrkyllisyyden mekanismit ovatkin huonosti ymmärrettyjä. Esimerkki myrkyllisyyden vaihtelevuudesta on kahden rottakanan herkkyysero myrkyllisimmälle 2,3,7,8-tetraklooridibentso-p-dioksiinille eli TCDD:lle: H/W-kannan rotat kestävät yli 1000 kertaa suurempia myrkkyannoksia kuin L E-kanta. Dioksiinien yksi harvoista monilla koe-eläimillä samanlaista, mutta herkkyyseroiltaan yhtä suurista, vaikutuksista on jo yhden myrkyllisen annoksen aiheuttama voimakas ruokahalun ja painon lasku, niin sanottu näivettymisoireyhtymä. Tutkimuksessani pyrin selvittämään näivettymisoireyhtymän mekanismeja altistamalla H/W- ja L E-rottia yhdelle annokselle TCDD:tä ja mittaamalla geenien ilmentymisen muutoksia hypotalamuksessa kvantitatiivista käänteiskopiointi-PCR (RT-qPCR) -menetelmää käyttäen. Mitatut lähetti-RNA:t tuottavat AH-reseptorin signalointiin liittyviä proteiineja ja syömisen säätelyyn liittyviä neuropeptidejä tai reseptoreita. Väitöskirjan toisessa osassa parannettiin herkän RT-qPCR-menetelmän luottavuutta etsimällä sen tarvitsemia kontrolligeenejä ja kartoittamalla käänteiskopiointi (RT)- ja PCR-reaktioiden virhelähteitä. Hypotalamuksen AH-reseptorin signalointireitti toimii, mutta lähetti-RNA:n perustasot tai niiden vähäiset muutokset TCDD:n annostelun jälkeen eivät näytä selittävän H/W ja L E-kantojen herkkyyseroja. Neuropeptideissä todettiin vain pieniä muutoksia, joten TCDD ei aiheuttane hypotalamuksen syömistä säätelevän järjestelmän solujen merkittäviä toiminnan muutoksia. Mittaukset tehtiin kokonaisista kudospaloista ja tämä voi estää tumaketason vaikutusten havaitsemisen, eikä myöskään huomioi tärkeitä hypotalamuksen ulkopuolisia syömistä ja energiatasapainoa sääteleviä järjestelmiä. TCDD:n aiheuttamiin myrkkyvaikutuksiin reagoimattomia kontrolligeenejä löytyi neljä ja näistä kahden lähetti-RNA:n käänteiskopiointi toimi luotettavasti. RT-qPCR-menetelmän analysointiin käytetty lineaarinen hierarkkinen malli ja beyesiläinen päättely toimivat hyvin RT- ja PCR-reaktioiden virhelähteiden erottelussa. Tämän tutkimuksen tulokset auttavat suuntaamaan tulevia näivettymisoireyhtymätutkimuksia ja parantamaan RT-qPCR-menetelmän luotettavuutta.

Psoriasis is an immune-mediated skin disorder that is inherited as a complex genetic trait. Although genome-wide association scans (GWAS) have identified 36 disease susceptibility regions, more than 50% of the genetic variance can be attributed to a single Major Histocompatibility Complex (MHC) locus, known as PSORS1. Genetic studies indicate that HLA-C is the strongest PSORS1 candidate gene, since markers tagging HLA-Cw*0602 consistently generate the most significant association signals in GWAS. However, it is unclear whether HLA-Cw*0602 is itself the causal PSORS1 allele, especially as the role of SNPs that may affect its expression has not been investigated. Here, we have undertaken an in-depth molecular characterization of the PSORS1 interval, with a view to identifying regulatory variants that may contribute to disease susceptibility. By analysing high-density SNP data, we refined PSORS1 to a 179 kb region encompassing HLA-C and the neighbouring HCG27 pseudogene. We compared multiple MHC sequences spanning this refined locus and identified 144 candidate susceptibility variants, which are unique to chromosomes bearing HLA-Cw*0602. In parallel, we investigated the epigenetic profile of the critical PSORS1 interval and uncovered three enhancer elements likely to be active in T lymphocytes. Finally we showed that nine candidate susceptibility SNPs map within a HLA-C enhancer and that three of these variants co-localise with binding sites for immune-related transcription factors. These data indicate that SNPs affecting HLA-Cw*0602 expression are likely to contribute to psoriasis susceptibility and highlight the importance of integrating multiple experimental approaches in the investigation of complex genomic regions such as the MHC., The authors acknowledge the use of BRC Core Facilities provided by the financial support from the Department of Health via the National Institute of Health Research (NIHR,www.nihr.ac.uk/) comprehensive Biomedical Research Centre award to Guy’s and St Thomas NHS Foundation Trust in partnership with King’s College London and King’s College Hospital NHS Foundation Trust. The British 1958 Birth Cohort DNA collection was funded by Medical Research Council (www.mrc.ac.uk) grant G0000934 and Wellcome Trust (www.wellcome.ac.uk) grant 068545/Z/02, and the UK National Blood Service controls by the Wellcome Trust. This work was supported by the Medical Research Council (grant G0601387 to RCT, JNB, FON and AH), the National Psoriasis Foundation USA (www. psoriasis.org; Discovery grant to FC) and Prime Minister’s Initiative 2 (PMI2)/partnership NPF127, for UK-US partnership between KCL and UCSF. AB’s studentship was funded by The Generation Trust.

The present report describes a three-step approach that was used to characterize and define thresholds for the Least Disturbed Condition in Mediterranean streams of four different types, regarding organic pollution and nutrients, hydrological and morphological alterations, and land use. For this purpose, a common database composed of national reference sites (929 records) from seven countries, sampled for invertebrates, diatoms and macrophytes was used. The analyses of reference sites showed that small (catchment100 km(2)) siliceous and non-siliceous streams were mainly affected by channelization, bank alteration and hydropeaking. Medium-sized siliceous rivers were the most affected by stressors: 25-43% of the samples showed at least slight alterations regarding channelization, connectivity, upstream dam influence, hydropeaking and degradation of riparian vegetation. Temporary streams were the least affected by hydromorphological changes, but they were nevertheless affected by alterations in riparian vegetation. There were no major differences between all permanent stream types regarding water quality, but temporary streams showed lower values for oxygenation (DO) and wider ranges for other variables, such as nitrates. A lower threshold value for DO (60%) was determined for this stream type and can be attributed to the streams' natural characteristics. For all other river types, common limits were found for the remaining variables (ammonium, nitrate, phosphate, total P, % of artificial areas, % of intensive and extensive agriculture, % of semi-natural areas in the catchment). These values were then used to select the list of reference sites. The biological communities were characterized, revealing the existence of nine groups of Mediterranean invertebrate communities, six for diatoms and five for macrophytes: each group was characterized by specific indicator taxa that highlighted the differences between groups.

Journal Article; Research Support, Non-U.S. Gov't; SUMMARY The main objective was to evaluate the association between SNPs and haplotypes of the FABP1-4 genes and type 2 diabetes, as well as its interaction with fat intake, in one general Spanish population. The association was replicated in a second population in which HOMA index was also evaluated. METHODS 1217 unrelated individuals were selected from a population-based study [Hortega study: 605 women; mean age 54 y; 7.8% with type 2 diabetes]. The replication population included 805 subjects from Segovia, a neighboring region of Spain (446 females; mean age 52 y; 10.3% with type 2 diabetes). DM2 mellitus was defined in a similar way in both studies. Fifteen SNPs previously associated with metabolic traits or with potential influence in the gene expression within the FABP1-4 genes were genotyped with SNPlex and tested. Age, sex and BMI were used as covariates in the logistic regression model. RESULTS One polymorphism (rs2197076) and two haplotypes of the FABP-1 showed a strong association with the risk of DM2 in the original population. This association was further confirmed in the second population as well as in the pooled sample. None of the other analyzed variants in FABP2, FABP3 and FABP4 genes were associated. There was not a formal interaction between rs2197076 and fat intake. A significant association between the rs2197076 and the haplotypes of the FABP1 and HOMA-IR was also present in the replication population. CONCLUSIONS The study supports the role of common variants of the FABP-1 gene in the development of type 2 diabetes in Caucasians. Yes

Subject Areas: carotid arteries; emulsions; fatty acids; gene expression; heparin; hypothalamus; neurons; oxidation.; International audience; Variations in plasma fatty acid (FA) concentrations are detected by FA sensing neurons in specific brain areas such as the hypothalamus. These neurons play a physiological role in the control of food intake and the regulation of hepatic glucose production. Le Foll et al. previously showed in vitro that at least 50% of the FA sensing in ventromedial hypothalamic (VMH) neurons is attributable to the interaction of long chain FA with FA translocase/CD36 (CD36). The present work assessed whether in vivo effects of hypothalamic FA sensing might be partly mediated by CD36 or intracellular events such as acylCoA synthesis or β-oxidation. To that end, a catheter was implanted in the carotid artery toward the brain in male Wistar rats. After 1 wk recovery, animals were food-deprived for 5 h, then 10 min infusions of triglyceride emulsion, Intralipid +/- heparin (IL, ILH, respectively) or saline/heparin (SH) were carried out and food intake was assessed over the next 5 h. Experimental groups included: 1) Rats previously injected in ventromedian nucleus (VMN) with shRNA against CD36 or scrambled RNA; 2) Etomoxir (CPT1 inhibitor) or saline co-infused with ILH/SH; and 3) Triacsin C (acylCoA synthase inhibitor) or saline co-infused with ILH/SH. ILH significantly lowered food intake during refeeding compared to SH (p

http://www.ncbi.nlm.nih.gov/pubmed/23894333; International audience; AIMS: Hypoglycemia is a severe side effect of intensive insulin therapy. Recurrent hypoglycemia (RH) impairs the counter-regulatory response (CRR) which restores euglycemia. During hypoglycemia, ventromedial hypothalamus (VMH) production of nitric oxide (NO) and activation of its receptor soluble guanylyl cyclase (sGC) are critical for the CRR. Hypoglycemia also increases brain reactive oxygen species (ROS) production. NO production in the presence of ROS causes protein S-nitrosylation. S-nitrosylation of sGC impairs its function and induces desensitization to NO. We hypothesized that during hypoglycemia, the interaction between NO and ROS increases VMH sGC S-nitrosylation levels and impairs the CRR to subsequent episodes of hypoglycemia. VMH ROS production and S-nitrosylation were quantified following three consecutive daily episodes of insulin-hypoglycemia (RH model). The CRR was evaluated in rats in response to acute insulin-induced hypoglycemia or via hypoglycemic-hyperinsulinemic clamps. Pretreatment with the anti-oxidant N-acetyl-cysteine (NAC) was used to prevent increased VMH S-nitrosylation.RESULTS: Acute insulin-hypoglycemia increased VMH ROS levels by 49±6.3%. RH increased VMH sGC S-nitrosylation. Increasing VMH S-nitrosylation with intracerebroventricular injection of the nitrosylating agent S-nitroso-L-cysteine (CSNO) was associated with decreased glucagon secretion during hypoglycemic clamp. Finally, in RH rats pre-treated with NAC (0.5% in drinking water for 9 days) hypoglycemia-induced VMH ROS production was prevented and glucagon and epinephrine production was not blunted in response to subsequent insulin-hypoglycemia.CONCLUSION: These data suggest that NAC may be clinically useful in preventing impaired CRR in patients undergoing intensive-insulin therapy.

Journal Article; Research Support, Non-U.S. Gov't; Review; Nonsteroidal anti-inflammatory drugs (NSAIDs) are used worldwide and are responsible for several types of drug hypersensitivity reactions (DHRs) in all age groups. The 2 major groups of DHRs to NSAIDs are those induced by immunological mechanisms (selective reactions) and those where inflammatory mediators are released through activation of the prostaglandin-leukotriene pathway without specific immunological recognition (cross-intolerance). In the present review, we focus on cross-intolerance reactions, which are the most frequent DHRs and are becoming a topic of major interest in children and adolescents. Paracetamol and ibuprofen are the drugs that most frequently cause DHRs in children; other NSAIDs are responsible for reactions in adolescents. In vivo and in vitro tests are of limited diagnostic value, with some exceptions for the less common selective reactions. In cross-intolerance, the clinical history and controlled administration are in many instances the only way to establish a diagnosis and look for alternatives. The clinical history is diagnostic when consistent symptoms occur repeatedly after exposure to NSAIDs with different chemical structures. Cutaneous and respiratory symptoms often co-occur in young children. The natural history of these reactions in children is unknown, and some patients can develop tolerance over time. Atopy remains a major risk factor for cross-intolerant reactions. The increasing interest in hypersensitivity to NSAIDs with improvements in patient phenotyping and the information provided by pharmacogenetics will improve our understanding and management of these reactions in the near future. Yes Los antiinflamatorios no esteroideos (AINEs) son ampliamente utilizados en todo el mundo y en todos los tramos de edad. Son responsables de un número importante de reacciones de hipersensibilidad a fármacos (RHFs), que no sólo afectan a adultos sino también a niños y adolescentes. Existen dos grandes grupos: reacciones selectivas, inducidas por mecanismos inmunológicos específicos, y de intolerancia cruzada (IC), donde se liberan mediadores inflamatorios en ausencia de reconocimiento inmunológico específico. En esta revisión nos ocuparemos de la IC, que es la causa más frecuente de RHFs y resulta de gran interés en niños y adolescentes. El paracetamol y el ibuprofeno son los medicamentos más frecuentemente implicados en las RHFs en niños. El uso diagnóstico de los tests in vivo e in vitro es muy limitado, con algunas excepciones en las reacciones selectivas. En las de IC, la historia clínica y la administración controlada son en ocasiones la única vía para confirmar el diagnóstico y determinar las alternativas terapéuticas más adecuadas. La historia clínica tiene valor diagnóstico cuando se reproducen síntomas consistentes repetidamente tras la exposición a AINEs no relacionados estructuralmente. En niños de corta edad es especialmente frecuente la combinación de síntomas cutáneos y respiratorios. Aunque se desconoce la historia natural de la IC en niños, es probable que se desarrolle tolerancia a lo largo de la vida. El fenotipado detallado junto con la información proporcionada por la fármaco-genética no sólo proporcionarán un conocimiento más preciso de la IC sino que también facilitará el manejo clínico de estos pacientes.

Error in Figure [...].