958 resultados para Negative symptoms


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Matrix sublimation has demonstrated to be a powerful approach for high-resolution matrix-assisted laser desorption ionization (MALDI) imaging of lipids, providing very homogeneous solvent-free deposition. This work presents a comprehensive study aiming to evaluate current and novel matrix candidates for high spatial resolution MALDI imaging mass spectrometry of lipids from tissue section after deposition by sublimation. For this purpose, 12 matrices including 2,5-dihydroxybenzoic acid (DHB), sinapinic acid (SA), α-cyano-4-hydroxycinnamic acid (CHCA), 2,6-dihydroxyacetphenone (DHA), 2',4',6'-trihydroxyacetophenone (THAP), 3-hydroxypicolinic acid (3-HPA), 1,8-bis(dimethylamino)naphthalene (DMAN), 1,8,9-anthracentriol (DIT), 1,5-diaminonapthalene (DAN), p-nitroaniline (NIT), 9-aminoacridine (9-AA), and 2-mercaptobenzothiazole (MBT) were investigated for lipid detection efficiency in both positive and negative ionization modes, matrix interferences, and stability under vacuum. For the most relevant matrices, ion maps of the different lipid species were obtained from tissue sections at high spatial resolution and the detected peaks were characterized by matrix-assisted laser desorption ionization time-of-flight/time-of-flight (MALDI-TOF/TOF) mass spectrometry. First proposed for imaging mass spectrometry (IMS) after sublimation, DAN has demonstrated to be of high efficiency providing rich lipid signatures in both positive and negative polarities with high vacuum stability and sub-20 μm resolution capacity. Ion images from adult mouse brain were generated with a 10 μm scanning resolution. Furthermore, ion images from adult mouse brain and whole-body fish tissue sections were also acquired in both polarity modes from the same tissue section at 100 μm spatial resolution. Sublimation of DAN represents an interesting approach to improve information with respect to currently employed matrices providing a deeper analysis of the lipidome by IMS.

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In humans, NK receptors are expressed by natural killer cells and some T cells, the latter of which are preferentially alphabetaTCR+ CD8+ cytolytic T lymphocytes (CTL). In this study we analyzed the expression of nine NK receptors (p58.1, p58.2, p70, p140, ILT2, NKRP1A, ZIN176, CD94 and CD94/NKG2A) in PBL from both healthy donors and melanoma patients. The percentages of NK receptor-positive T cells (NKT cells) varied strongly, and this variation was more important between individual patients than between individual healthy donors. In all the individuals, the NKT cells were preferentially CD28-, and a significant correlation was found between the percentage of CD28- T cells and the percentage of NK receptor+ T cells. Based on these data and the known activated phenotype of CD28- T cells, we propose that the CD28- CD8+ T cell pool represents or contains the currently active CTL population, and that the frequent expression of NK receptors reflects regulatory mechanisms modulating the extent of CTL effector function. Preliminary results indicate that some tumor antigen-specific T cells may indeed be CD28- and express NK receptors in vivo.

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Purpose (1) To identify work related stressors that are associated with psychiatric symptoms in a Swiss sample of policemen and (2) to develop a model for identifying officers at risk for developing mental health problems. Method The study design is cross sectional. A total of 354 male police officers answered a questionnaire assessing a wide spectrum of work related stressors. Psychiatric symptoms were assessed using the "TST questionnaire" (Langner in J Health Hum Behav 4, 269-276, 1962). Logistic regression with backward procedure was used to identify a set of variables collectively associated with high scores for psychiatric symptoms. Results A total of 42 (11.9%) officers had a high score for psychiatric symptoms. Nearly all potential stressors considered were significantly associated (at P < 0.05) with a high score for psychiatric symptoms. A significant model including 6 independent variables was identified: lack of support from superior and organization OR = 3.58 (1.58-8.13), self perception of bad quality work OR = 2.99 (1.35-6.59), inadequate work schedule OR = 2.84 (1.22-6.62), high mental/intellectual demand OR = 2.56 (1.12-5.86), age (in decades) OR = 1.82 (1.21-2.73), and score for physical environment complaints OR = 1.30 (1.03-1.64). Conclusions Most of work stressors considered are associated with psychiatric symptoms. Prevention should target the most frequent stressors with high association to symptoms. Complaints of police officers about stressors should receive proper consideration by the management of public administration. Such complaints might be the expression of psychiatric caseness requiring medical assistance. Particular attention should be given to police officers complaining about many stressors identified in this study's multiple model. [Authors]

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Ethyl glucuronide (EtG) is a minor and direct metabolite of ethanol. EtG is incorporated into the growing hair allowing retrospective investigation of chronic alcohol abuse. In this study, we report the development and the validation of a method using gas chromatography-negative chemical ionization tandem mass spectrometry (GC-NCI-MS/MS) for the quantification of EtG in hair. EtG was extracted from about 30 mg of hair by aqueous incubation and purified by solid-phase extraction (SPE) using mixed mode extraction cartridges followed by derivation with perfluoropentanoic anhydride (PFPA). The analysis was performed in the selected reaction monitoring (SRM) mode using the transitions m/z 347-->163 (for the quantification) and m/z 347-->119 (for the identification) for EtG, and m/z 352-->163 for EtG-d(5) used as internal standard. For validation, we prepared quality controls (QC) using hair samples taken post mortem from 2 subjects with a known history of alcoholism. These samples were confirmed by a proficiency test with 7 participating laboratories. The assay linearity of EtG was confirmed over the range from 8.4 to 259.4 pg/mg hair, with a coefficient of determination (r(2)) above 0.999. The limit of detection (LOD) was estimated with 3.0 pg/mg. The lower limit of quantification (LLOQ) of the method was fixed at 8.4 pg/mg. Repeatability and intermediate precision (relative standard deviation, RSD%), tested at 4 QC levels, were less than 13.2%. The analytical method was applied to several hair samples obtained from autopsy cases with a history of alcoholism and/or lesions caused by alcohol. EtG concentrations in hair ranged from 60 to 820 pg/mg hair.

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Notch signalling has an important role in skin homeostasis, promoting keratinocyte differentiation and suppressing tumorigenesis. Here we show that this pathway also has an essential anti-apoptotic function in the keratinocyte UVB response. Notch1 expression and activity are significantly induced, in a p53-dependent manner, by UVB exposure of primary keratinocytes as well as intact epidermis of both mouse and human origin. The apoptotic response to UVB is increased by deletion of the Notch1 gene or down-modulation of Notch signalling by pharmacological inhibition or genetic suppression of 'canonical' Notch/CSL/MAML1-dependent transcription. Conversely, Notch activation protects keratinocytes against apoptosis through a mechanism that is not linked to Notch-induced cell cycle withdrawal or NF-kappaB activation. Rather, transcription of FoxO3a, a key pro-apoptotic gene, is under direct negative control of Notch/HERP transcription in keratinocytes, and upregulation of this gene accounts for the increased susceptibility to UVB of cells with suppressed Notch signalling. Thus, the canonical Notch/HERP pathway functions as a protective anti-apoptotic mechanism in keratinocytes through negative control of FoxO3a expression.

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Preterm birth may represent a traumatic situation for both parents and a stressful situation for the infant, potentially leading to difficulties in mother-infant relationships. This study aimed to investigate the impact of an early intervention on maternal posttraumatic stress symptoms, and on the quality of mother-infant interactions, in a sample of very preterm infants and their mothers. Half of the very preterm infants involved in the study (n=26) were randomly assigned to a 3-step early intervention program (at 33 and 42 weeks after conception and at 4 months' corrected age). Both groups of preterm infants (with and without intervention) were compared to a group of full-term infants. The impact of the intervention on maternal posttraumatic stress symptoms was assessed 42 weeks after conception and when the infants were 4 and 12 months of age. The impact of the intervention on the quality of mother-infant interactions was assessed when the infants were 4 months old. Results showed a lowering of mothers' posttraumatic stress symptoms between 42 weeks and 12 months in the group of preterm infants who received the intervention. Moreover, an enhancement in maternal sensitivity and infant cooperation during interactions was found at 4 months in the group with intervention. In the case of a preterm birth, an early intervention aimed at enhancing the quality of the mother-infant relationship can help to alleviate maternal post-traumatic stress symptoms and may have a positive impact on the quality of mother-infant interactions.

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Intellectual disability has long been associated with deficits in socio-emotional processing. However, studies investigating brain dynamics of maladaptive socio-emotional skills associated with intellectual disability are scarce. Here, we compared differences in brain activity between low intelligence quotient (I.Q.<75, N=13) and normal controls (N=15) while evaluating their subjective emotions. Positive (P) and negative (N) valenced pictures were presented one at a time to participants of both groups, at a rate of ¾. The task required that each participant evaluate their subjective emotion and press a predefined push-button when done, alternatively P and N. Electroencephalographic (EEG) signals were continuously recorded, and the 1000ms time window following each picture was analyzed offline for power in frequency domain. Alpha low (8-10Hz) and upper (10-13Hz) frequency bands were then compared for both groups and for both P and N emotions in 12 distributed scalp electrodes. The qualitative evaluation of emotions was similar between both groups, with constant longer reaction times for the low IQ participants. The EEG signal comparison shows marked power decrease in upper alpha frequency range for N emotions in low intelligence group. Otherwise no significant difference was noticed between low and normal IQ. Main findings of the present study are (1) results do not support the hypothesis that impairment in developmental intelligence roots in maladaptive emotional processing; (2) the strong alpha power suppression during negative-induced emotions suggests the involvement of an extended neural network and more effortful inhibition processes than positive ones. We call for further studies with a larger sample.

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OBJECTIVE: To assess the survival benefit and safety profile of low-dose (850 mg/kg) and high-dose (1350 mg/kg) phospholipid emulsion vs. placebo administered as a continuous 3-day infusion in patients with confirmed or suspected Gram-negative severe sepsis. Preclinical and ex vivo studies show that lipoproteins bind and neutralize endotoxin, and experimental animal studies demonstrate protection from septic death when lipoproteins are administered. Endotoxin neutralization correlates with the amount of phospholipid in the lipoprotein particles. DESIGN: A three-arm, randomized, blinded, placebo-controlled trial. SETTING: Conducted at 235 centers worldwide between September 2004 and April 2006. PATIENTS: A total of 1379 patients participated in the study, 598 patients received low-dose phospholipid emulsion, and 599 patients received placebo. The high-dose phospholipid emulsion arm was stopped, on the recommendation of the Independent Data Monitoring Committee, due to an increase in life-threatening serious adverse events at the fourth interim analysis and included 182 patients. MEASUREMENTS AND MAIN RESULTS: A 28-day all-cause mortality and new-onset organ failure. There was no significant treatment benefit for low- or high-dose phospholipid emulsion vs. placebo for 28-day all-cause mortality, with rates of 25.8% (p = .329), 31.3% (p = .879), and 26.9%, respectively. The rate of new-onset organ failure was not statistically different among groups at 26.3%, 31.3%, 20.4% with low- and high-dose phospholipid emulsion, and placebo, respectively (one-sided p = .992, low vs. placebo; p = .999, high vs. placebo). Of the subjects treated, 45% had microbiologically confirmed Gram-negative infections. Maximal changes in mean hemoglobin levels were reached on day 10 (-1.04 g/dL) and day 5 (-1.36 g/dL) with low- and high-dose phospholipid emulsion, respectively, and on day 14 (-0.82 g/dL) with placebo. CONCLUSIONS: Treatment with phospholipid emulsion did not reduce 28-day all-cause mortality, or reduce the onset of new organ failure in patients with suspected or confirmed Gram-negative severe sepsis.

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BACKGROUND: Active screening by mobile teams is considered the best method for detecting human African trypanosomiasis (HAT) caused by Trypanosoma brucei gambiense but the current funding context in many post-conflict countries limits this approach. As an alternative, non-specialist health care workers (HCWs) in peripheral health facilities could be trained to identify potential cases who need testing based on their symptoms. We explored the predictive value of syndromic referral algorithms to identify symptomatic cases of HAT among a treatment-seeking population in Nimule, South Sudan. METHODOLOGY/PRINCIPAL FINDINGS: Symptom data from 462 patients (27 cases) presenting for a HAT test via passive screening over a 7 month period were collected to construct and evaluate over 14,000 four item syndromic algorithms considered simple enough to be used by peripheral HCWs. For comparison, algorithms developed in other settings were also tested on our data, and a panel of expert HAT clinicians were asked to make referral decisions based on the symptom dataset. The best performing algorithms consisted of three core symptoms (sleep problems, neurological problems and weight loss), with or without a history of oedema, cervical adenopathy or proximity to livestock. They had a sensitivity of 88.9-92.6%, a negative predictive value of up to 98.8% and a positive predictive value in this context of 8.4-8.7%. In terms of sensitivity, these out-performed more complex algorithms identified in other studies, as well as the expert panel. The best-performing algorithm is predicted to identify about 9/10 treatment-seeking HAT cases, though only 1/10 patients referred would test positive. CONCLUSIONS/SIGNIFICANCE: In the absence of regular active screening, improving referrals of HAT patients through other means is essential. Systematic use of syndromic algorithms by peripheral HCWs has the potential to increase case detection and would increase their participation in HAT programmes. The algorithms proposed here, though promising, should be validated elsewhere.

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PURPOSE: Attention deficit and hyperactivity disorder (ADHD) is one of the most frequent disorders in childhood and adolescence. Both neurocognitive and environmental factors have been related to ADHD. The current study contributes to the documentation of the predictive relation between early attachment deprivation and ADHD. METHOD: Data were collected from 641 adopted adolescents (53.2 % girls) aged 11-16 years in five countries, using the DSM oriented scale for ADHD of the Child Behavior Checklist (CBCL) (Achenbach and Rescorla, Manual for the ASEBA school-age forms and profiles. University of Vermont, Research Center for Children, Youth and Families, Burlington, 2001). The influence of attachment deprivation on ADHD symptoms was initially tested taking into consideration several key variables that have been reported as influencing ADHD at the adoptee level (age, gender, length of time in the adoptive family, parents' educational level and marital status), and at the level of the country of origin and country of adoption (poverty, quality of health services and values). The analyses were computed using the multilevel modeling technique. RESULTS: The results showed that an increase in the level of ADHD symptoms was predicted by the duration of exposure to early attachment deprivation, estimated from the age of adoption, after controlling for the influence of adoptee and country variables. The effect of the age of adoption was also demonstrated to be specific to the level of ADHD symptoms in comparison to both the externalizing and internalizing behavior scales of the CBCL. CONCLUSION: Deprivation of stable and sensitive care in infancy may have long-lasting consequences for children's development.

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Résumé Objectifs : Alors que de nombreuses études suggèrent que l'exposition au tabagisme passif représente un danger pour la santé des non-fumeurs, la plupart des études s'intéressant aux effets néfastes du tabagisme passif sur la santé respiratoire de sujets adultes étaient des études transversales. Les résultats d'études longitudinales restent rares et controversés. Le but de notre étude était de mesurer les effets d'une exposition antérieure au tabagisme passif sur l'évolution journalière de quatre catégories de symptômes respiratoires dans une étude journalière incluant des adultes n'ayant jamais fumé. Méthodes : Dans le cadre de l'étude SAPALDIA (Swiss study on air pollution and lung diseases in adults), nous avons mené une étude de cohorte prospective et multicentrique. 1421 adultes n'ayant jamais fumé étaient suivis durant deux ans sur la base de questionnaires journaliers remplis durant une à six périodes de quatre semaines répartis sur deux années (1992-1993). Nous avons ensuite déterminé le risque relatif (RR) de développer ou de s'amender de symptômes respiratoires en association avec une exposition antérieure au tabagisme passif. Résultats : Dans un échantillon d'adultes n'ayant jamais fumé, nous avons trouvé une association entre une exposition antérieure au tabagisme passif et une évolution péjorée de tous les symptômes respiratoires étudiés, montrant un risque relatif de 1.09 à 1.21 de développer les symptômes respiratoires, et un risque relatif de 0.91 à 0.83 de s'amender de ces symptômes. Une exposition au tabagisme passif sur la place de travail était associée à une diminution de la durée des intervalles libres sans symptômes bronchitiques (RR 1.33) et asthmatiques (RR 1.27), alors qu'une exposition uniquement en-dehors de la place de travail était associée avec un allongement de la durée des épisodes avec symptômes respiratoires des voies aériennes hautes ou basses (RR 0.78-0.77). Conclusion : Nos résultats suggèrent que l'exposition au tabagisme passif a des effets néfastes sur la dynamique journalière symptômes respiratoires, et que l'importance et le type d'effet sont influencés par le lieu d'exposition.

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ABSTRACTSchizophrenia is a major psychiatric disorder occurring with a prevalence of 1% in the worldwide population. It develops progressively with psychosis onset in late adolescence or earlyadulthood. The disorder can take many different facets and has a highly diffuse anddistributed neuropathology including deficits in major neurotransmitter systems,myelination, stress regulation, and metabolism. The delayed onset and the heterogeneouspathology suggest that schizophrenia is a developmental disease that arises from interplayof genetic and environmental factors during sensitive periods. Redox dysregulation due to animbalance between pro-oxidants and antioxidant defence mechanisms is among the riskfactors for schizophrenia. Glutathione (GSH) is the major cellular redox regulator andantioxidant. Levels of GSH are decreased in cerebrospinal fluid, prefrontal cortex and postmortemstriatum of schizophrenia patients. Moreover, polymorphisms of the key GSHsynthesizingenzyme, glutamate-cysteine ligase, modifier (GCLM) subunit, are associatedwith the disease, suggesting that GSH deficit is of genetic origin. Here we used miceknockout (KO) for the GCLM gene, which display chronic GSH deficit (~70 to 80% decrease)to investigate the direct link between redox dysregulation and schizophrenia. Accordingly,we evaluated whether GCLM KO compared to normal wildtype mice display behavioralchanges that relate to schizophrenia symptoms and whether their brains showmorphological, functional or metabolic alterations that resemble those in patients.Moreover, we exposed pubertal GCLM mice to repeated mild stress and measured theirhormonal and behavioral stress reactivity. Our data show that chronic GSH deficit isassociated with altered emotion- and stress-related behaviors, deficient prepulse inhibition,pronounced amphetamine-induced hyperlocomotion but normal spatial learning andworking memory. These changes represent important schizophrenia endophenotypes.Moreover, this particular pattern of change indicates impairment of the ventralhippocampus (VH) and related circuitry as opposed to the dorsal hippocampus (DH), which isimplicated in spatial information processing. This is consistent with a selective deficit ofparvalbumin positive interneurons and gamma oscillation in the VH but not DH. Increasedlevels of circulating stress hormones in KO mice following pubertal stress corroborate VHdysfunction as it is involved in negative feedback control of the stress response. VHstructural and functional deficits are frequently found in the schizophrenic brain. Metabolicevaluation of the developing GCLM KO anterior cortex using in vivo magnetic resonancespectroscopy revealed elevated glutamine (Gln), glutamate (Glu), Gln/Glu and N-acetylaspartate(NAA) during the pre-pubertal period. Similar changes are reported in earlyschizophrenia. Overall, we observe phenotypic anomalies in GSH deficient GCLM KO micethat correspond to major schizophrenia endophenotypes. This supports an important rolefor redox dysregulation in schizophrenia and validates the GCLM KO mouse as model for thedisease. Moreover, our results indicate that puberty may be a sensitive period for redoxsensitivechanges highliting the importance of early intervention. Gln, Gln/Glu, Glu and NAAmay qualify as early metabolic biomarkers to identify young at-risk individuals. Since chronictreatment with NAC normalized most metabolic changes in GCLM KO mice, NAC may be oneadjunct treatment of choice for early intervention in patients.RESUMELa schizophrénie est une maladie psychiatrique majeure avec une prévalence de 1% dans lapopulation. Son développement est progressif, les premières psychoses apparaissant àl'adolescence ou au début de l'âge adulte. La maladie a plusieurs présentations et uneneuropathologie étendue, qui inclut des déficits neurochimiques, métaboliques, de lamyélination et de la régulation du stress. L'émergence tardive et l'hétérogénéité de lapathologie suggèrent que la schizophrénie est une maladie développementale, favorisée pardes facteurs génétiques et environnementaux durant des périodes sensibles. La dérégulationrédox, due à un déséquilibre entre facteurs pro-oxidantes et défenses anti-oxidantes,constitue un facteur de risque. Le glutathion (GSH) est le principal régulateur rédox et antioxidantdes cellules, ses taux sont diminués dans le liquide céphalorachidien, le cortexpréfrontal et le striatum de patients. De plus, des variations du gène codant la sous-unitémodulatrice (GCLM) de la glutamate-cystéine ligase, enzyme de synthèse du GSH, sontassociés la maladie, suggérant que le déficit observé chez les patients est d'originegénétique. Nous avons donc utilisé des souris ayant une délétion du gène GCLM (KO), quiont un déficit chronique en GSH (70-80%), afin d'étudier le lien entre une dérégulation rédoxet la schizophrénie. Nous avons évalué si ces souris présentent des altérationscomportementales analogues aux symptômes de la maladie, et des modificationsstructurelles, fonctionnelles et métaboliques au niveau du cerveau, ressemblant à celles despatients. De plus, nous avons soumis les souris à des stresses modérés durant la puberté,puis mesuré les réponses hormonales et comportementales. Les animaux présentent undéficit pré-attentionnel du traitement des informations moto-sensorielles, un déficit pourcertains apprentissages, une réponse accrue à l'amphétamine, mais leurs mémoires spatialeet de travail sont préservées. Ces atteintes comportementales sont analogues à certainsendophénotypes de la schizophrénie. De plus, ces changements comportementaux sontlargement expliqués par une perturbation morphologique et fonctionnelle de l'hippocampeventral (HV). Ainsi, nous avons observé un déficit sélectif des interneurones immunoréactifsà la parvalbumine et une désynchronisation neuronale dans l'HV. L'hippocampe dorsal,impliqué dans l'orientation spatiale, demeure en revanche intact. L'augmentationd'hormones de stress dans le sang des souris KO suite à un stress prépubertal soutien aussil'hypothèse d'une dysfonction de l'HV, connu pour moduler ce type de réponse. Des déficitsstructurels et fonctionnels dans l'hippocampe antérieur (ventral) ont d'ailleurs été rapportéschez des patients schizophrènes. Par de résonance magnétique, nous avons également suivile profil métabolique du le cortex antérieur au cours du développement postnatal des sourisKO. Ces mesures ont révélé des taux élevés de glutamine (Gln), glutamate (Glu), du ratioGln/Glu, et de N-acétyl-aspartate (NAA) durant la période prépubertale. Des altérationssimilaires sont décrites chez les patients durant la phase précoce. Nous avons donc révélédes anomalies phénotypiques chez les souris GCLM KO qui reflètent certainsendophénotypes de la schizophrénie. Nos résultats appuient donc le rôle d'une dérégulationrédox dans l'émergence de la maladie et le potentiel des souris KO comme modèle. De plus,cette étude met en évidence la puberté comme période particulièrement sensible à unedérégulation rédox, renforçant l'importance d'une intervention thérapeutique précoce. Dansce cadre, Gln, Gln/Glu, Glu and NAA seraient des biomarqueurs clés pour identifier de jeunesindividus à risque. De part son efficacité dans notre modèle, NAC pourrait être unesubstance de choix dans le traitement précoce des patients.

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The TNF family ligand ectodysplasin A (EDA) regulates the induction, morphogenesis and/or maintenance of skin-derived structures such as teeth, hair, sweat glands and several other glands. Deficiencies in the EDA - EDA receptor (EDAR) signalling pathway cause hypohidrotic ectodermal dysplasia (HED). This syndrome is characterized by the absence or malformation of several skin-derived appendages resulting in hypotrychosis, hypodontia, heat-intolerance, dry skin and dry eyes, susceptibility to airways infections and crusting of various secretions. The EDA-EDAR system is an important effector of canonical Wnt signalling in developing skin appendages. It functions by stimulating NF-κB-mediated transcription of effectors or inhibitors of the Wnt, Sonic hedgehog (SHH), fibroblast growth factor (FGF) and transforming growth factor beta (TGFβ) pathways that regulate interactions within or between epithelial and mesenchymal cells and tissues. In animal models of Eda-deficiency, soluble EDAR agonists can precisely correct clinically relevant symptoms with low side effects even at high agonist doses, indicating that efficient negative feedback signals occur in treated tissues. Hijacking of the placental antibody transport system can help deliver active molecules to developing foetuses in a timely manner. EDAR agonists may serve to treat certain forms of ectodermal dysplasia.

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Multi-span pre-tensioned pre-stressed concrete beam (PPCB) bridges made continuous usually experience a negative live load moment region over the intermediate supports. Conventional thinking dictates that sufficient reinforcement must be provided in this region to satisfy the strength and serviceability requirements associated with the tensile stresses in the deck. The American Association of State Highway and Transportation Officials (AASHTO) Load and Resistance Factor Design (LRFD) Bridge Design Specifications recommend the negative moment reinforcement (b2 reinforcement) be extended beyond the inflection point. Based upon satisfactory previous performance and judgment, the Iowa Department of Transportation (DOT) Office of Bridges and Structures (OBS) currently terminates b2 reinforcement at 1/8 of the span length. Although the Iowa DOT policy results in approximately 50% shorter b2 reinforcement than the AASHTO LRFD specifications, the Iowa DOT has not experienced any significant deck cracking over the intermediate supports. The primary objective of this project was to investigate the Iowa DOT OBS policy regarding the required amount of b2 reinforcement to provide the continuity over bridge decks. Other parameters, such as termination length, termination pattern, and effects of the secondary moments, were also studied. Live load tests were carried out on five bridges. The data were used to calibrate three-dimensional finite element models of two bridges. Parametric studies were conducted on the bridges with an uncracked deck, a cracked deck, and a cracked deck with a cracked pier diaphragm for live load and shrinkage load. The general conclusions were as follows: -- The parametric study results show that an increased area of the b2 reinforcement slightly reduces the strain over the pier, whereas an increased length and staggered reinforcement pattern slightly reduce the strains of the deck at 1/8 of the span length. -- Finite element modeling results suggest that the transverse field cracks over the pier and at 1/8 of the span length are mainly due to deck shrinkage. -- Bridges with larger skew angles have lower strains over the intermediate supports. -- Secondary moments affect the behavior in the negative moment region. The impact may be significant enough such that no tensile stresses in the deck may be experienced.