995 resultados para ACTH challenge test


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The expansion of the specialty of sports and exercise medicine (SEM) is a relatively recent development in the medical community and the role of the SEM specialist continues to evolve and develop. The SEM specialist is ideally placed to care for all aspects of physical activity not only in athletes but also in the general population. As an advocate for physical activity the SEM specialist plays a broad role in advising safe effective sports and recreation participation; screening for disease related to sports participation; examining and contributing to the evidence behind treatment strategies and evaluating any potential negative impact of sports injury prevention measures. In this thesis I will demonstrate the breadth of the role the Sports and Exercise Medicine Specialist from epidemiology to in-depth examination of treatment strategies. In Chapter 2, I examined the epidemiology of sports and recreation related injury (SRI) in Ireland, an area that has previously been poorly studied. We report on 3,172 SRI (14% of total presentations) presentations to the ED over 6 months. Paediatric patients (4-16 yrs) were over represented comprising 39.9% of all SRI presentation compared to 16% of total ED presentations and 18% of the general population. These injuries were serious (32% fractures) and though 49% of injuries occurred during organised competition/practice, 41.5% occurred during recreation-most often at home. In Chapter 3, I examined risk factors associated with hand injury in hurling. The previous chapter highlighted the importance of a firm evidence base underpinning treatment strategies. When measures to improve welfare are introduced not only must potential benefits be measured, so too must potential unwanted adverse outcomes. In this study I examined a cohort of adult hurlers who had presented to the ED with a hurling related injury in order to highlight the variables associated with hand injury in this population. I found the athletes who wore a helmet were far more likely (OR 3.15 95% CI (1.51-6.56) p= 0.002) to suffer a hand injury than athletes who did not. Very few of those interviewed (4.9%) used hand protection compared to 65% who used helmet and faceguard. The introduction of the helmet and faceguard in hurling has undeniably decreased the incidence of head and face injury in hurling. However in tandem with this intervention several observational studies have demonstrated an increase in the occurrence of hurling related hand injuries. This study highlights the importance of being cognisant of unanticipated or unintended consequences when implementing a new treatment or intervention. In Chapter 4, I examined the role of population screening as applied to sport and exercise. This is a controversial area –cardiac screening in the exercising population has been the subject of much debate. Specifically I define the prevalence of exercise induced bronchoconstriction (EIB) using a specifically designed sports specific field-testing protocol. In this study I found almost a third (29%) of a full international professional rugby squad had confirmed asthma or EIB, as compared with 12-15% of the general population. Despite regular medical screening, 5 ‘new’ untreated cases (12%) were elicited by the challenge test and in the group already on treatment for asthma/EIB; over 50% still displayed EIB. In Chapter 5, I examined the evidence supporting current treatment options for iliotibial band friction syndrome (ITBFS). The practice of sports medicine has traditionally been ‘eminence based’ rather than ‘evidence based’. This may be problematic as some of these practices are based upon flawed principles- for example the treatment of iliotibial band friction syndrome (ITBFS). In this chapter, using cadaveric and biomechanical studies I expand upon the growing base of evidence clarifying the anatomy and biomechanics of the area-thereby re-examining the principles on which current treatments are based. The role of the SEM specialist is broad; we chose to examine specific examples of some of the roles that they execute. An understanding of the epidemiology of SRI presenting to the ED has implications for individual patients, sports governing bodies and health resource utilisation. Population screening is an important tool in health promotion and disease prevention in the general population. Screening in SEM may have similar less well-recognised benefits. The SEM specialist needs to be conversant in screening for medical conditions concerning physical activity. A comprehensive understanding of the pathophysiology of a disease is required for its diagnosis and treatment. Due to the ongoing evolution of SEM many treatments are eminence-based rather than evidence‐based practice. Continued re-examination of the fundamentals of current practice is essential. An awareness of potential unwanted side effects is essential prior to the introduction of any new treatment or intervention. The SEM specialist is ideally placed to advise sports governing bodies on these issues prior to and during their implementation.

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Scopo della tesi è la valutazione del potenziale di crescita (δ) di Listeria monocytogenes espressa come differenza tra il carico cellulare (log10 ufc/g) alla fine e all’inizio della prova, in monoporzioni di battuta di vitello (tartare) confezionate sottovuoto e conservate a temperatura di refrigerazione. Si tratta di un alimento ready to eat – RTE – prodotto dalla Ditta INALCA Spa e destinato ad una catena di ristorazione. I challenge test hanno lo scopo di fornire informazioni sul comportamento in determinate condizioni di conservazione, di L. monocytogenes inoculata artificialmente in un alimento. L. monocytogenes è un microrganismo patogeno ubiquitario nell’ambiente e resistente a diverse condizioni ambientali. E’ stato dimostrato che il batterio è responsabile della contaminazione post-processo degli alimenti, in quanto è stato isolato da impianti di trasformazione, macchine per l’imballaggio, nastri trasportatori, guanti, congelatori e guarnizioni. Sono state oggetto di studio: - i) 3 u.c. inoculate con soluzione fisiologica sterile su cui sono stati valutati Aw, pH, carica aerobia mesofila, batteri lattici, Pseudomonas, Enterobacteriaceae, muffe e lieviti; - ii) 1 u.c. non soggetta ad alcun inoculo per la ricerca qualitativa/quantitativa di L. monocytogenes; - iii) 9 u.c. contaminate con una miscela di 5 ceppi di L. monocytogenes (circa 100 ufc/g). Le confezioni inoculate sono state conservate per 21 giorni (pari alla shelf-life commerciale), di cui i primi 7 alla temperatura di +3°C, ed i successivi 14 giorni a +5°C. Il valore δ è risultato pari a 0.57: essendo superiore, seppure di poco, al valore soglia 0.5, le tartare in esame sono classificate come alimenti pronti che costituiscono terreno favorevole alla crescita di L. monocytogenes (categoria 1.2); in base al regolamento (CE) 2073/2005, il microrganismo deve essere assente in 25 g alla produzione e < 100 ufc/g durante la shelf–life (nota 5 e 7).

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The European sea bass (Dicentrarchus labrax) is an economically important fish native to the Mediterranean and Northern Atlantic. Its complex life cycle involves many migrations through temperature gradients that affect the energetic demands of swimming. Previous studies have shown large intraspecific variation in swimming performance and temperature tolerance, which could include deleterious and advantageous traits under the evolutionary pressure of climate change. However, little is known of the underlying determinants of this individual variation. We investigated individual variation in temperature tolerance in 30 sea bass by exposing them to a warm temperature challenge test. The eight most temperature-tolerant and eight most temperature-sensitive fish were then studied further to determine maximal swimming speed (U-CAT), aerobic scope and post-exercise oxygen consumption. Finally, ventricular contractility in each group was determined using isometric muscle preparations. The temperature-tolerant fish showed lower resting oxygen consumption rates, possessed larger hearts and initially recovered from exhaustive exercise faster than the temperature-sensitive fish. Thus, whole-animal temperature tolerance was associated with important performance traits. However, the temperature-tolerant fish also demonstrated poorer maximal swimming capacity (i.e. lower UCAT) than their temperature-sensitive counterparts, which may indicate a trade-off between temperature tolerance and swimming performance. Interestingly, the larger relative ventricular mass of the temperature-tolerant fish did not equate to greater ventricular contractility, suggesting that larger stroke volumes, rather than greater contractile strength, may be associated with thermal tolerance in this species.

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L’ipertiroidismo felino rappresenta oggi la più comune endocrinopatia della specie. I capitoli 2 e 3 costituiscono una revisione della letteratura in merito agli aspetti clinici, diagnostici e terapeutici della patologia. Il capitolo 4 indaga il ruolo della dimetilarginina simmetrica (SDMA) come marker di funzionalità renale nei gatti ipertiroidei prima e dopo terapia medica. La patologia tiroidea più comune nel cane è l’ipotiroidismo. Nello studio riportato al capitolo 5 sono state indagate le performance diagnostiche di freeT3, freeT4, rT3, 3,3-T2 e 3,5-T2, misurati tramite LC-MS/MS, nel differenziare tra cani ipotiroidei, cani con patologie non-tiroidee e cani sani. La presenza di una possibile correlazione tra la gravità della condizione clinica dei pazienti ipotiroidei, le variabili emato-chimiche e le concentrazioni sieriche di cTSH è stata valutata nel capitolo 6. Il capitolo 7 valuta l’andamento dell’SDMA in cani ipotiroidei prima e dopo supplementazione ormonale. A differenza della Sindrome di Cushing dell’uomo, che è considerata una malattia rara, nel cane l’ipercortisolismo spontaneo (HC) è una delle endocrinopatie più comuni. Gli aspetti epidemiologici dell’HC e la ricerca di un metodo di monitoraggio alternativo al test di stimolazione con ACTH nei cani trattati con Trilostano sono stati approfonditi rispettivamente nei capitoli 8 e 9. A differenza dell'HC, l'ipoadrenocorticismo primario (PH) è una patologia rara nel cane. Lo scopo dello studio riportato nel capitolo 10 consiste nel descrivere le frazioni escretorie degli elettroliti urinari nei cani con PH e di indagare se esse possano rappresentare un utile supporto alla diagnosi e al trattamento del PH canino. Il riscontro accidentale di masse surrenaliche rappresenta una criticità diagnostica. Infatti, può essere difficile distinguere morfologicamente tra lesioni corticali e midollari e tra lesioni maligne e benigne. Nel capitolo 11 vengono descritti i rilievi immunoistochimici dell'incidentaloma surrenalico nel cane e viene valutato il ruolo del Ki-67 PI come indicatore di malignità.

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Il lavoro svolto in questa tesi aveva l’obiettivo di valutare il potenziale tecnologico e bioprotettivo di ceppi di batteri lattici (LAB) isolati da salami tradizionali spagnoli. In particolare due ceppi (Lactiplantibacillus paraplantarum BPF2 e Pediococcus acidilactici ST6) che avevano dimostrato buone performance in vitro sono stati utilizzati, da soli o in miscela, come colture starter per la produzione salami e i prodotti ottenuti sono stati confrontati con un controllo a fermentazione spontanea ed un prodotto addizionato di uno starter commerciale contenente LAB e stafilococchi. Per quanto riguarda gli aspetti tecnologici, il pH ha mostrato cinetiche di acidificazione simili in tutti i prodotti, mentre il calo peso era più lento nel controllo. A livello microbiologico, i campioni addizionati di colture starter hanno mostrato carichi di LAB molto più elevati già al tempo zero, senza differenze significative in relazione al ceppo utilizzato. Enterobatteri e lieviti hanno mostrato andamenti simili in tutti i campioni. L’utilizzo di colture starter ha invece avuto un impatto rilevante sul contenuto di ammine biogene, con valori totali doppi nel campione ottenuto con fermentazione spontanea, e sul profilo in metaboliti volatili (soprattutto a carico di composti derivanti dall’acido piruvico). L’aspetto più rilevante di questa tesi è stato ottenuto nel challenge test, utilizzando come microrganismo target Listeria monocytogenes (inoculo 3 log ufc/g): infatti, nel controllo e nei campioni contenenti starter commerciale, L. monocytogenes era in grado di crescere fino a valori superiori a 5.7 log ufc/g, mentre i ceppi BPF2 e ST6 hanno determinato una riduzione del suo carico cellulare (2.4 log ufc/g). Questo conferma quindi le grandi potenzialità anti-listeria dei due ceppi testati e la loro attitudine ad essere utilizzati, oltre che come starter per i salami, anche come colture bioprotettive con lo specifico compito di contrastare lo sviluppo di L. monocytogenes.

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Significant work has been done in the areas of Pervcomp/Ubicomp Smart Environments with advances on making proactive systems, but those advances have not made these type of systems accurately proactive. On the other hand a great deal is needed to make systems more sensible/sensitive and trustable (both in terms of reliability and privacy). We put forward the thesis that a more integral and social-aware sort of intelligence is needed to effectively interact, decide and act on behalf of people’s interest and that a way to test how effective systems are achieving these desirable behaviour is needed as a consequence. We support our thesis by providing examples on how to measure effectiveness in variety of different environments.

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BACKGROUND: Although long-term implications of cancer in childhood or adolescence with regard to medical conditions are well documented, the impact on mental health and on response to stress, which may be an indicator of psychological vulnerability, is not yet well understood. In this study, psychological and physiological responses to stress were examined.¦PROCEDURE: Fifty-three participants aged 18-39 years (n = 25 survivors of childhood or adolescence cancer, n = 28 controls) underwent an experimental stress test, the Trier Social Stress Test (TSST). Participants were asked to provide repeated evaluations of perceived stress on visual-analogical scales and blood samples were collected before and after the TSST to measure plasma cortisol.¦RESULTS: The psychological perception of stress was not different between the two groups. However, the cancer survivors group showed a higher global plasma cortisol level as well as higher amplitude in the response to the TSST. The global cortisol level in cancer survivors was increased when depression symptoms were present. The subjective perception of stress and the plasma cortisol levels were only marginally correlated in both groups.¦CONCLUSIONS: It is suggested that the exposure to a life-threatening experience in childhood/adolescence increases the endocrine response to stress, and that the presence of depressive symptoms is associated with an elevation of plasma cortisol levels. A better knowledge of these mechanisms is important given that the dysregulations of the stress responses may cause psychological vulnerability. Pediatr Blood Cancer 2012; 59: 138-143. © 2011 Wiley Periodicals, Inc.

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Rapport de synthèseEnjeux et contexteL'épidémie d'obésité est un enjeu majeur de santé publique, et l'augmentation parallèle du nombre de patients obèses admis aux soins intensifs appelle à une meilleure connaissance des spécificités de la physiopathologie de cette population. De nombreuses anomalies physiologiques associées à l'obésité sont connues, notamment une inflammation sub-clinique chronique. Cependant, les connaissances concernant la réponse inflammatoire lors d'une agression des sujets obèses sont pour l'heure assez limitées. Bien que les réponses inflammatoires in vitro du tissu adipeux soient augmentées, les données in vivo sont pour l'instant non-conclusives.L'injection intraveineuse d'endotoxine est un test hautement reproductible provoquant une inflammation de durée limitée. Il s'agit d'un test validé pour l'étude in vivo lors des réponses inflammatoires. L'endotoxine est un lipopolysaccharide contenu dans les membranes externes des bactéries gram- négatives, notamment de E.Coli. Notre équipe possède une expérience de ces tests avec endotoxine acquise lors d'une série de recherches sur les propriétés modulatrices de l'inflammation des acides gras polyinsaturés oméga-3.Lors de l'élaboration de ce projet, la réponse du sujet obèse à l'endotoxine restait méconnue. L'objectif de l'essai est d'étudier les spécificités des réponses à l'endotoxine, notre hypothèse étant que les réponses physiologiques, métaboliques et endocrines sont amplifiées chez cette catégorie de sujets.Présentation de l'étudeAfin de tester notre hypothèse, nous avons conçu une étude prospective randomisée, avec 2 procédures (injection d'endotoxine vs de placebo) en cross-over: le protocole d'investigation durait chaque fois 8h. Huit volontaires obèses grade I (BMI médian de 33.8 kg/m2) sans morbidité ont été enrôlés. Les variables étudiées étaient: les fréquences cardiaque et respiratoire, la température, la tension artérielle, le débit cardiaque et la saturation veineuse en oxygène, ainsi qu'une calorimétrie indirecte en continu. Les symptômes tels que myalgie, céphalée et nausée ont également été consignés. Des marqueurs hormonaux et inflammatoires (Cortisol, ACTH, catécholamines, insuline, glucose, glucagon, leptine, TNF-alpha, IL-6 et CRP) ont été dosés de manière répétée.Statistiques : Pour limiter les effets de la variabilité inter-individuelle et permettre une comparaison des réponses, le calcul des aires sous la courbe (AUC) selon la méthode trapézoïdale a été utilisé. Le groupe étudié étant de « petite taille », bien ceci soit habituel pour les études de physiologie, et les réponses n'étant pas normalement distribuées, des tests non-paramétriques ont été appliqués : nous savons que la puissance statistique de notre étude est limitée. Considérant les désagréments majeurs (bien que rapidement réversibles) vécus par les volontaires soumis à des infections d'endotoxine, leurs réponses ont été comparées de manières qualitative à celles des non-obèse mesurés lors de précédentes études pour éviter de répliquer ces expériences désagréables et parfaitement prévisibles.Les résultats de cette étude sont parfaitement superposables à celles trouvées chez les sujets de BMI normal, invalidant notre hypothèse de départ d'une éventuelle réponse exacerbée.Conclusions et perspectivesCette étude est la première publication concernant la réponse du patient obèse à un test d'endotoxine. La similitude des résultats chez les patients obèses et non-obèses montre que l'obésité n'est pas en soi un facteur augmentant les réponses inflammatoires.Ces résultats concernent des sujets obèses sains et ne peuvent pas être extrapolés aux sujets obèses avec comorbidités, appelant à de futures investigations chez cette catégorie de patients.

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Résumé Introduction et hypothèse : Certains acides gras polyinsaturés de type n-3 PUFA, qui sont contenus dans l'huile de poisson, exercent des effets non-énergétiques (fluidité des membranes cellulaires, métabolisme énergétique et prostanoïdes, régulation génique de la réponse inflammatoire). Les mécanismes de la modulation de cette dernière sont encore mal connus. L'administration d'endotoxine (LPS) induit chez les volontaires sains une affection inflammatoire aiguë, comparable à un état grippal, associé à des modifications métaboliques et inflammatoires transitoires, similaires au sepsis. Ce modèle est utilisé de longue date pour l'investigation clinique expérimentale. Cette étude examine les effets d'une supplémentation orale d'huile de poisson sur la réponse inflammatoire (systémique et endocrinienne) de sujets sains soumis à une injection d'endotoxine. L'hypothèse était que la supplémentation d'huile de poisson réduirait les réponses physiologiques à l'endotoxine. Méthodes : Quinze volontaires masculins (âge 26.0±3.1 ans) ont participé à une étude randomisée, contrôlée. Les sujets sont désignés au hasard à recevoir ou non une supplémentation orale : 7.2 g d'huile de poisson par jour correspondant à un apport de 1.1 g/jour d'acides gras 20:5 (n-3, acide écosapentaénoïque) et 0.7 g/jour de 22:6 (n-3, acide docosahexaénoïque). Chaque sujet est investigué deux fois dans des conditions identiques : une fois il reçoit une injection de 2 ng par kg poids corporel de LPS intraveineuse, l'autre fois une injection de placebo. Les variables suivantes sont relevées avant l'intervention et durant les 360 min qui suivent l'injection :signes vitaux, dépense énergétique (EE) et utilisation nette des substrats (calorimétrie indirecte, cinétique du glucose (isotopes stables), taux plasmatique des triglycérides et FFA, du glucose, ainsi que des cytokines et hormones de stress (ACTH, cortisol, Adré, Nor-Adré). Analyses et statistiques :moyennes, déviations standards, analyse de variance (one way, test de Scheffé), différences significatives entre les groupes pour une valeur de p < 0.05. Résultats :L'injection de LPS provoque une augmentation de la température, de la fréquence cardiaque, de la dépense d'énergie et de l'oxydation nette des lipides. On observe une élévation des taux plasmatiques de TNF-a et IL-6, de la glycémie, ainsi qu'une élévation transitoire des concentrations plasmatiques des hormones de stress ACTH, cortisol, adrénaline et noradrénaline. L'huile de poisson atténue significativement la fièvre, la réponse neuro-endocrinienne (ACTH et cortisol) et sympathique (baisse de la noradrénaline plasmatique). Par contre, les taux des cytokines ne sont pas influencés par la supplémentation d'huile de poisson. Conclusion : La supplémentation d'huile de poisson atténue la réponse physiologique à l'endotoxine chez le sujet sain, en particulier la fièvre et la réponse endocrinienne, sans influencer la production des cytokines. Ces résultats soutiennent l'hypothèse que les effets bénéfiques de l'huile de poisson sont principalement caractérisés au niveau du système nerveux central, par des mécanismes non-inflammatoires qui restent encore à élucider.

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Chatterbox Challenge is an annual web-based contest for artificial conversational systems, ACE. The 2010 instantiation was the tenth consecutive contest held between March and June in the 60th year following the publication of Alan Turing’s influential disquisition ‘computing machinery and intelligence’. Loosely based on Turing’s viva voca interrogator-hidden witness imitation game, a thought experiment to ascertain a machine’s capacity to respond satisfactorily to unrestricted questions, the contest provides a platform for technology comparison and evaluation. This paper provides an insight into emotion content in the entries since the 2005 Chatterbox Challenge. The authors find that synthetic textual systems, none of which are backed by academic or industry funding, are, on the whole and more than half a century since Weizenbaum’s natural language understanding experiment, little further than Eliza in terms of expressing emotion in dialogue. This may be a failure on the part of the academic AI community for ignoring the Turing test as an engineering challenge.

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This paper assesses the performance of a vocabulary test designed to measure second language productive vocabulary knowledge.The test, Lex30, uses a word association task to elicit vocabulary, and uses word frequency data to measure the vocabulary produced. Here we report firstly on the reliability of the test as measured by a test-retest study, a parallel test forms experiment and an internal consistency measure. We then investigate the construct validity of the test by looking at changes in test performance over time, analyses of correlations with scores on similar tests, and comparison of spoken and written test performance. Last, we examine the theoretical bases of the two main test components: eliciting vocabulary and measuring vocabulary. Interpretations of our findings are discussed in the context of test validation research literature. We conclude that the findings reported here present a robust argument for the validity of the test as a research tool, and encourage further investigation of its validity in an instructional context

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Many engineers currently in professional practice will have gained a degree level qualification which involved studying a curriculum heavy with mathematics and engineering science. While this knowledge is vital to the engineering design process so also is manufacturing knowledge, if the resulting designs are to be both technically and commercially viable.
The methodology advanced by the CDIO Initiative aims to improve engineering education by teaching in the context of Conceiving, Designing, Implementing and Operating products, processes or systems. A key element of this approach is the use of Design-Built-Test (DBT) projects as the core of an integrated curriculum. This approach facilitates the development of professional skills as well as the application of technical knowledge and skills developed in other parts of the degree programme. This approach also changes the role of lecturer to that of facilitator / coach in an active learning environment in which students gain concrete experiences that support their development.
The case study herein describes Mechanical Engineering undergraduate student involvement in the manufacture and assembly of concept and functional prototypes of a folding bicycle.

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Objective: GH secretagogues (GHS) produce exaggerated ACTH and cortisol responses in Cushing`s disease (CD) patients, attributable to their direct action on GH-releasing peptide receptor type la (GHSR-1a). However, there are no studies correlating the ill vivo response to GHS and GHSR-1a mRNA expression in ACTH-dependent Cushing`s syndrome (CS) patients. The aim of this study is to correlate the patterns of ACTH and cortisol response to GH-releasing peptide-6 (GHRP-6) to GHSR-1a expression in ACTH-dependent CS patients Design: Prospective study in a tertiary referral hospital center. Fifteen CD patients and two ectopic ACTH syndrome (EAS) patients were studied. Methods: Tumor fragments were submitted to RNA extraction, and GHSR-1a expression was studied through real-time qPCR and compared with normal tissue samples. The patients were also submitted to desmopressin test and vasopressin receptor type 1B (AVPR1B) mRNA analysis by qPCR. Results: GHSR-1a expression was similar in normal pituitary samples and in corticotrophic tumor samples. GHSR-1a expression was higher in patients (CD and EAS) presenting ill vivo response to GHRP-6. Higher expression of AVPR1B was observed in the EAS patients responsive to desmopressin, as well as in corticotrophic tumors, as compared with normal pituitary samples, but no correlation between AVPR1B expression and response to desmopressin was observed in the CD patients. Conclusions: Our results revealed a higher expression of GHSR-1a in the ACTH-dependent CS patients responsive to GHRP-6, suggesting an association between receptor gene expression and ill vivo response to the secretagogue in both the CD and the EAS patients.