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1.
Phys Med Biol ; 66(23)2021 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-34706355

RESUMEN

This work provides a quantitative assessment of helium ion CT (HeCT) for particle therapy treatment planning. For the first time, HeCT based range prediction accuracy in a heterogeneous tissue phantom is presented and compared to single-energy x-ray CT (SECT), dual-energy x-ray CT (DECT) and proton CT (pCT). HeCT and pCT scans were acquired using the US pCT collaboration prototype particle CT scanner at the Heidelberg Ion-Beam Therapy Center. SECT and DECT scans were done with a Siemens Somatom Definition Flash and converted to RSP. A Catphan CTP404 module was used to study the RSP accuracy of HeCT. A custom phantom of 20 cm diameter containing several tissue equivalent plastic cubes was used to assess the spatial resolution of HeCT and compare it to DECT. A clinically realistic heterogeneous tissue phantom was constructed using cranial slices from a pig head placed inside a cylindrical phantom (ø150 mm). A proton beam (84.67 mm range) depth-dose measurement was acquired using a stack of GafchromicTM EBT-XD films in a central dosimetry insert in the phantom. CT scans of the phantom were acquired with each modality, and proton depth-dose estimates were simulated based on the reconstructions. The RSP accuracy of HeCT for the plastic phantom was found to be 0.3 ± 0.1%. The spatial resolution for HeCT of the cube phantom was 5.9 ± 0.4 lp cm-1for central, and 7.6 ± 0.8 lp cm-1for peripheral cubes, comparable to DECT spatial resolution (7.7 ± 0.3 lp cm-1and 7.4 ± 0.2 lp cm-1, respectively). For the pig head, HeCT, SECT, DECT and pCT predicted range accuracy was 0.25%, -1.40%, -0.45% and 0.39%, respectively. In this study, HeCT acquired with a prototype system showed potential for particle therapy treatment planning, offering RSP accuracy, spatial resolution, and range prediction accuracy comparable to that achieved with a commercial DECT scanner. Still, technical improvements of HeCT are needed to enable clinical implementation.


Asunto(s)
Helio , Protones , Animales , Helio/uso terapéutico , Fantasmas de Imagen , Plásticos , Porcinos , Tomografía Computarizada por Rayos X , Rayos X
2.
Spinal Cord ; 56(1): 63-70, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28853447

RESUMEN

STUDY DESIGN: Cross-sectional, observational. OBJECTIVES: To investigate the association of conflicts between work and family life with indicators of health and to examine the antecedents of those conflicts in employees with spinal cord injury (SCI) and their caregiving partners. SETTING: Community, Switzerland. METHODS: Data from employed persons with SCI (n=79) and caregiving partners (n=93) who participated in the pro-WELL study were used. Logistic and tobit regressions were performed to assess the association of work-family and family-work conflicts with health indicators, namely mental health (36-item Short Form Health Survey (SF-36)), vitality (SF-36), well-being (WHOQoL BREF) and positive and negative affect (Positive and Negative Affect Scale short form (PANAS-S)). Own and partners' engagement in productive activities and socioeconomic circumstances were evaluated as potential antecedents of work-family and family-work conflicts using logistic regression. RESULTS: Work-family conflicts were related to reduced mental health (caregiving partners only), vitality and well-being. Family-work conflicts were linked to reduced mental health, vitality, well-being and positive affect in SCI and to reduced vitality in caregiving partners. Persons with lower income (SCI only) and lower subjective social position reported more conflicts than persons with higher income and higher subjective position. Higher workload increased work-family conflicts in caregiving partners and decreased family-work conflicts in SCI. Education, amount of caregiving, care-receiving and partners' employment status were not associated with the occurrence of conflicts. CONCLUSION: The optimal balance between work and family life is important to promote mental health, vitality and well-being in employees with SCI and their caregiving partners. This is especially true in employees perceiving their social position as low and in caregivers with a high workload.


Asunto(s)
Cuidadores/psicología , Empleo , Conflicto Familiar/psicología , Traumatismos de la Médula Espinal/psicología , Adulto , Femenino , Estado de Salud , Encuestas Epidemiológicas , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Características de la Residencia , Traumatismos de la Médula Espinal/epidemiología , Traumatismos de la Médula Espinal/enfermería , Estadísticas no Paramétricas , Suiza/epidemiología
3.
Endocrinology ; 157(6): 2356-66, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27046436

RESUMEN

The hypothalamic activation of thyroid hormones by type 2 deiodinase (D2), catalyzing the conversion of thyroxine to T3, is critical for the proper function of the hypothalamo-pituitary-thyroid (HPT) axis. Regulation of D2 expression in tanycytes alters the activity of the HPT axis. However, signals that regulate D2 expression in tanycytes are poorly understood. The pituitary adenylate cyclase-activating polypeptide (PACAP) increases intracellular cAMP level, a second messenger known to stimulate the DIO2 gene; however, its importance in tanycytes is not completely characterized. Therefore, we tested whether this ubiquitously expressed neuropeptide regulates the HPT axis through stimulation of D2 in tanycytes. PACAP increased the activity of human DIO2 promoter in luciferase reporter assay that was abolished by mutation of cAMP-response element. Furthermore, PAC1R receptor immunoreactivity was identified in hypothalamic tanycytes, suggesting that these D2-expressing cells could be regulated by PACAP. Intracerebroventricular PACAP administration resulted in increased D2 activity in the mediobasal hypothalamus, suppressed Trh expression in the hypothalamic paraventricular nucleus, and decreased Tshb expression in the pituitary demonstrating that PACAP affects the D2-mediated control of the HPT axis. To understand the role of endogenous PACAP in the regulation of HPT axis, the effect of decreased PACAP expression was studied in heterozygous Adcyap1 (PACAP) knockout mice. These animals were hypothyroid that may be the consequence of altered hypothalamic T3 degradation during set-point formation of the HPT axis. In conclusion, PACAP is an endogenous regulator of the HPT axis by affecting T3-mediated negative feedback via cAMP-induced D2 expression of tanycytes.


Asunto(s)
Hipotálamo/efectos de los fármacos , Hipotálamo/metabolismo , Yoduro Peroxidasa/metabolismo , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/metabolismo , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/farmacología , Hipófisis/efectos de los fármacos , Hipófisis/metabolismo , Glándula Tiroides/efectos de los fármacos , Glándula Tiroides/metabolismo , Animales , Western Blotting , Células HEK293 , Humanos , Inmunohistoquímica , Yoduro Peroxidasa/genética , Masculino , Ratones , Ratones Noqueados , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/genética , Hormonas Tiroideas/metabolismo , Tirotropina/metabolismo , Yodotironina Deyodinasa Tipo II
4.
Endocrinology ; 157(3): 1211-21, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26779746

RESUMEN

The hypothalamic-pituitary-thyroid axis is governed by hypophysiotropic TRH-synthesizing neurons located in the hypothalamic paraventricular nucleus under control of the negative feedback of thyroid hormones. The mechanisms underlying the ontogeny of this phenomenon are poorly understood. We aimed to determine the onset of thyroid hormone-mediated hypothalamic-negative feedback and studied how local hypothalamic metabolism of thyroid hormones could contribute to this process in developing chicken. In situ hybridization revealed that whereas exogenous T4 did not induce a statistically significant inhibition of TRH expression in the paraventricular nucleus at embryonic day (E)19, T4 treatment was effective at 2 days after hatching (P2). In contrast, TRH expression responded to T3 treatment in both age groups. TSHß mRNA expression in the pituitary responded to T4 in a similar age-dependent manner. Type 2 deiodinase (D2) was expressed from E13 in tanycytes of the mediobasal hypothalamus, and its activity increased between E15 and P2 both in the mediobasal hypothalamus and in tanycyte-lacking hypothalamic regions. Nkx2.1 was coexpressed with D2 in E13 and P2 tanycytes and transcription of the cdio2 gene responded to Nkx2.1 in U87 glioma cells, indicating its potential role in the developmental regulation of D2 activity. The T3-degrading D3 enzyme was also detected in tanycytes, but its level was not markedly changed before and after the period of negative feedback acquisition. These findings suggest that increasing the D2-mediated T3 generation during E18-P2 could provide the sufficient local T3 concentration required for the onset of T3-dependent negative feedback in the developing chicken hypothalamus.


Asunto(s)
Retroalimentación Fisiológica/fisiología , Regulación del Desarrollo de la Expresión Génica/genética , Sistema Hipotálamo-Hipofisario/metabolismo , Yoduro Peroxidasa/metabolismo , Neuronas/metabolismo , Núcleo Hipotalámico Paraventricular/metabolismo , ARN Mensajero/metabolismo , Glándula Tiroides/metabolismo , Hormona Liberadora de Tirotropina/metabolismo , Tiroxina/metabolismo , Animales , Encéfalo/efectos de los fármacos , Encéfalo/embriología , Encéfalo/metabolismo , Línea Celular Tumoral , Embrión de Pollo , Células Ependimogliales/efectos de los fármacos , Células Ependimogliales/metabolismo , Retroalimentación Fisiológica/efectos de los fármacos , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Humanos , Sistema Hipotálamo-Hipofisario/embriología , Hipotálamo/efectos de los fármacos , Hipotálamo/embriología , Hipotálamo/metabolismo , Inmunohistoquímica , Hibridación in Situ , Yoduro Peroxidasa/efectos de los fármacos , Neuronas/efectos de los fármacos , Proteínas Nucleares/efectos de los fármacos , Proteínas Nucleares/metabolismo , Núcleo Hipotalámico Paraventricular/efectos de los fármacos , Núcleo Hipotalámico Paraventricular/embriología , Hipófisis/efectos de los fármacos , Hipófisis/metabolismo , ARN Mensajero/efectos de los fármacos , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor Nuclear Tiroideo 1 , Tirotropina de Subunidad beta/genética , Tiroxina/farmacología , Factores de Transcripción/efectos de los fármacos , Factores de Transcripción/metabolismo , Triyodotironina/efectos de los fármacos , Triyodotironina/metabolismo , Yodotironina Deyodinasa Tipo II
5.
Spinal Cord ; 54(7): 553-60, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26481705

RESUMEN

STUDY DESIGN: Cross-sectional validation study. OBJECTIVES: To validate the Italian version of the Spinal Cord Independence Measure Self-Report (SCIM SR). SETTING: Two spinal cord injury (SCI) rehabilitation facilities in Italy. METHODS: The SCIM III comprises items on 19 daily tasks, grouped into three subscales: 'Self-care,' 'Respiration and sphincter management' and 'Mobility'. The total SCIM score ranges between 0 and 100. The Italian self-reported version (SCIM SR) was translated from the German tool. We studied 116 patients on their first hospitalization for rehabilitation after an SCI. At the time of discharge, patients were evaluated by the rehabilitation team using the SCIM III and self-assessed their independence with regard to activities of daily living using the SCIM SR. Pearson's correlation, Bland-Altman method, and stratified and regression analyses were used to examine the differences between evaluations. RESULTS: On the basis of Pearson's correlation, there was good agreement between the data from the SCIM III and SCIM SR (r=0.918 for 'Self-care,' 0.806 for 'Respiration and sphincter management,' 0.906 for 'Mobility' and 0.934 for total scores). By Bland-Altman analysis, patients rated their functioning nearly the same as professionals-the mean difference between SCIM III and SCIM SR scores was approximately 0 for all subscales and total scores. The stratified and regression analyses failed to identify any specific factor that was associated with differences between SCIM III and SCIM SR scores. CONCLUSIONS: These results support the validity of the Italian version of the SCIM SR, which can facilitate longer-term evaluations of the independence of individuals with SCIs.


Asunto(s)
Evaluación de Resultado en la Atención de Salud/métodos , Traumatismos de la Médula Espinal/psicología , Traumatismos de la Médula Espinal/rehabilitación , Resultado del Tratamiento , Adulto , Estudios Transversales , Evaluación de la Discapacidad , Femenino , Hospitalización , Humanos , Italia , Masculino , Persona de Mediana Edad , Análisis de Regresión , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Traducción
6.
Sci Rep ; 5: 11525, 2015 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-26089239

RESUMEN

Few studies have included subjects with the propensity to reach old age in good health, with the aim to disentangle mechanisms contributing to staying healthier for longer. The hypothalamic-pituitary-thyroid (HPT) axis maintains circulating levels of thyroid stimulating hormone (TSH) and thyroid hormone (TH) in an inverse relationship. Greater longevity has been associated with higher TSH and lower TH levels, but mechanisms underlying TSH/TH differences and longevity remain unknown. The HPT axis plays a pivotal role in growth, development and energy metabolism. We report that offspring of nonagenarians with at least one nonagenarian sibling have increased TSH secretion but similar bioactivity of TSH and similar TH levels compared to controls. Healthy offspring and spousal controls had similar resting metabolic rate and core body temperature. We propose that pleiotropic effects of the HPT axis may favour longevity without altering energy metabolism.


Asunto(s)
Metabolismo Energético , Longevidad , Tirotropina/metabolismo , Anciano de 80 o más Años , Comorbilidad , Familia , Femenino , Humanos , Sistema Hipotálamo-Hipofisario/metabolismo , Yodo/metabolismo , Masculino , Factores de Riesgo , Hormonas Tiroideas/sangre , Hormonas Tiroideas/metabolismo , Tirotropina/sangre
7.
Spinal Cord ; 52(9): 706-11, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24937697

RESUMEN

STUDY DESIGN: Secondary data analysis of a questionnaire-based, cross-sectional survey in persons with spinal cord injury (SCI) in Switzerland. OBJECTIVE: To describe the frequency of participation in sport (PiS) and to identify correlates for PiS in persons with SCI in Switzerland. SETTING: Community sampleMethods:Frequency of PiS was assessed retrospectively for the time before the onset of SCI and the time of the survey using a single-item question. A comprehensive set of independent variables was selected from the original questionnaire. Descriptive statistics, bivariate analyses and ordinal regressions were carried out. RESULTS: Data from 505 participants were analyzed. Twenty independent variables were selected for analyses. PiS decreased significantly from the time before the onset of SCI to the time of the survey (P<0.001). Sport levels were significantly lower in women than men for the time of the survey (P<0.001), whereas no difference was observed before onset of SCI (P=0.446). Persons with tetraplegia participated significantly less often in sport than persons with paraplegia (P<0.001). Lesion level, active membership in a club, frequency of PiS before the onset of SCI and the subjective evaluation of the importance of sport correlate with PiS. When controlling for gender differences, only the subjective importance of sport for persons with SCI determines PiS, particularly among women. CONCLUSIONS: Persons with tetraplegia and women need special attention when planning interventions to improve PiS. Furthermore, the subjective importance of sport is important for PiS, particularly among women, whereas most other factors were only weakly associated with PiS.


Asunto(s)
Traumatismos de la Médula Espinal , Deportes , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Encuestas y Cuestionarios , Suiza
8.
Spinal Cord ; 51(1): 40-7, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22890418

RESUMEN

STUDY DESIGN: Cross-sectional validation study. OBJECTIVES: To develop and validate a self-report version of the Spinal Cord Independence Measure (SCIM III). SETTING: Two SCI rehabilitation facilities in Switzerland. METHODS: SCIM III comprises 19 questions on daily tasks with a total score between 0 and 100 and subscales for 'self-care', 'respiration & sphincter management' and 'mobility'. A self-report version (SCIM-SR) was developed by expert discussions and pretests in individuals with spinal cord injury (SCI) using a German translation. A convenience sample of 99 inpatients with SCI was recruited. SCIM-SR data were analyzed together with SCIM III data obtained from attending health professionals. RESULTS: High correlations between SCIM III and SCIM-SR were observed. Pearson's r for the total score was 0.87 (95% confidence interval (CI) 0.82-0.91), for the subscales self-care 0.87 (0.81-0.91); respiration & sphincter management 0.81 (0.73-0.87); and mobility 0.87 (0.82-0.91). Intraclass correlations were: total score 0.90 (95% CI 0.85-0.93); self-care 0.86 (0.79-0.90); respiration & sphincter management 0.80 (0.71-0.86); and mobility 0.83 (0.76-0.89). Bland-Altman plots showed that patients rated their functioning higher than professionals, in particular for mobility. The mean difference between SCIM-SR and SCIM III for the total score was 5.14 (point estimate 95% CI 2.95-7.34), self-care 0.89 (0.19-1.59), respiration & sphincter management 1.05 (0.18-2.28 ) and mobility 3.49 (2.44-4.54). Particularly patients readmitted because of pressure sores rated their independence higher than attending professionals. CONCLUSION: Our results support the criterion validity of SCIM-SR. The self-report version may facilitate long-term evaluations of independence in persons with SCI in their home situation.


Asunto(s)
Vida Independiente/psicología , Traumatismos de la Médula Espinal/psicología , Actividades Cotidianas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Evaluación de la Discapacidad , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Vida Independiente/estadística & datos numéricos , Lenguaje , Masculino , Persona de Mediana Edad , Centros de Rehabilitación , Reproducibilidad de los Resultados , Autoinforme , Factores Socioeconómicos , Encuestas y Cuestionarios , Suiza , Resultado del Tratamiento , Adulto Joven
9.
J Neuroendocrinol ; 24(11): 1423-31, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22734660

RESUMEN

After fasting, satiety is observed within 2 h after reintroducing food, accompanied by activation of anorexigenic, pro-opiomelanocortin (POMC)-synthesising neurones in the arcuate nucleus (ARC), indicative of the critical role that α-melanocyte-stimulating hormone has in the regulation of meal size during refeeding. To determine whether refeeding-induced activation of POMC neurones in the arcuate is dependent upon the vagus nerve and/or ascending brainstem pathways, bilateral subdiaphragmatic vagotomy or transection of the afferent brainstem input to one side of the ARC was performed. One day after vagotomy or 2 weeks after brain surgery, animals were fasted and then refed for 2 h. Sections containing the ARC from vagotomised animals or animals with effective transection were immunostained for c-Fos and POMC to detect refeeding-induced activation of POMC neurones. Quantitative analyses of double-labelled preparations demonstrated that sham-operated and vagotomised animals markedly increased the number of c-Fos-immunoreactive (-IR) POMC neurones with refeeding. Furthermore, transection of the ascending brainstem pathway had no effect on diminishing c-Fos-immunoreactivity in POMC neurones on either side of the ARC, although it did diminish activation in a separate, subpopulation of neurones in the dorsomedial posterior ARC (dmpARC) on the transected side. We conclude that inputs mediated via the vagus nerve and/or arising from the brainstem do not have a primary role in refeeding-induced activation of POMC neurones in the ARC, and propose that these neurones may be activated solely by direct effects of circulating hormones/metabolites during refeeding. Activation of the dmpARC by refeeding indicates a previously unrecognised role for these neurones in appetite regulation in the rat.


Asunto(s)
Tronco Encefálico/fisiología , Ingestión de Alimentos/fisiología , Neuronas/metabolismo , Neuronas/fisiología , Proopiomelanocortina/metabolismo , Nervio Vago/fisiología , Animales , Anorexia/metabolismo , Depresores del Apetito/metabolismo , Regulación del Apetito/fisiología , Núcleo Arqueado del Hipotálamo/metabolismo , Núcleo Arqueado del Hipotálamo/fisiología , Tronco Encefálico/metabolismo , Ingestión de Líquidos/fisiología , Ayuno , Masculino , Ratas , Ratas Sprague-Dawley , Transmisión Sináptica/fisiología , Nervio Vago/metabolismo
10.
J Neuroendocrinol ; 24(6): 930-43, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22295972

RESUMEN

Interleukin (IL)-6 deficient mice develop mature-onset obesity. Furthermore, i.c.v. administration of IL-6 increases energy expenditure, suggesting that IL-6 centrally regulates energy homeostasis. To investigate whether it would be possible for IL-6 to directly influence the energy homeostasis via hypothalamic regulation in humans and rodents, we mapped the distribution of the ligand binding IL-6 receptor α (IL-6Rα) in this brain region. In the human hypothalamus, IL-6Rα-immunoreactivity was detected in perikarya and first-order dendrites of neurones. The IL-6Rα-immunoreactive (-IR) neurones were observed posterior to the level of the interventricular foramen. There, IL-6Rα-IR neurones were located in the lateral hypothalamic, perifornical, dorsal and posterior hypothalamic areas, the hypothalamic dorsomedial nucleus and in the zona incerta. In the caudal part of the hypothalamus, the density of the IL-6Rα-IR neurones gradually increased. Double-labelling immunofluorescent studies demonstrated that IL-6Rα immunoreactivity was localised in the same neurones as the orexigenic neuropeptide, melanin-concentrating hormone (MCH). By contrast, IL-6Rα-immunoreactivity was not observed in the orexin B-IR neurones. To determine whether the observed expression of IL-6Rα is evolutionary conserved, we studied the co-localisation of IL-6Rα with MCH and orexin in the mouse hypothalamus, where IL-6Rα-immunoreactivity was present in numerous MCH-IR and orexin-IR neurones. Our data demonstrate that the MCH neurones of the human hypothalamus, as well as the MCH and orexin neurones of the mouse hypothalamus, contain IL-6Rα. This opens up the possibility that IL-6 influences the energy balance through the MCH neurones in humans, and both MCH and orexin neurones in mice.


Asunto(s)
Hormonas Hipotalámicas/metabolismo , Hipotálamo/metabolismo , Melaninas/metabolismo , Hormonas Hipofisarias/metabolismo , Receptores de Interleucina-6/metabolismo , Adulto , Animales , Humanos , Hormonas Hipotalámicas/fisiología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Masculino , Melaninas/fisiología , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Neuropéptidos/metabolismo , Orexinas , Hormonas Hipofisarias/fisiología
11.
J Clin Endocrinol Metab ; 96(12): 3785-93, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21956412

RESUMEN

BACKGROUND: Morphological studies of the pancreas in persistent hyperinsulinemic hypoglycemia of infancy (PHHI) have focused on the diagnosis of focal vs. diffuse forms, a distinction that determines the optimal surgical management. ABCC8 or KCNJ11 genomic mutations are present in most of them. AIM: Our aim was to report a new form of PHHI with peculiar morphological and clinical characteristics. RESEARCH DESIGN AND METHODS: Histopathological review of 217 pancreatic PHHI specimens revealed 16 cases morphologically different from diffuse and focal forms. They were analyzed by conventional microscopy, quantitative morphometry, immunohistochemistry, and in situ hybridization. RESULTS: Their morphological peculiarity was the coexistence of two types of islet: large islets with cytoplasm-rich ß-cells and occasional enlarged nuclei and shrunken islets with ß-cells exhibiting little cytoplasm and small nuclei. In small islets, ß-cells had abundant insulin content but limited amount of Golgi proinsulin. Large islets had low insulin storage and high proinsulin production and were mostly confined to a few lobules. No evidence for K(ATP) channels involvement or 11p15 deletion was found. Genomic mutations for ABCC8, KCNJ11, and GCK were absent. Patients had normal birth weight and late hypoglycemia onset and improved with diazoxide. Ten were cured by limited pancreatectomy. Six recurred after surgery and were medically controlled. CONCLUSION: This new form of PHHI is characterized by a morphological mosaicism. Pathologists should recognize this mosaicism on intraoperative frozen sections because it is often curable by partial pancreatectomy. The currently unknown genetic background does not involve the classical genomic mutations responsible for diffuse and focal PHHI.


Asunto(s)
Hiperinsulinismo Congénito/patología , Islotes Pancreáticos/patología , Hiperinsulinismo Congénito/genética , Hiperinsulinismo Congénito/cirugía , Femenino , Humanos , Lactante , Recién Nacido , Islotes Pancreáticos/cirugía , Masculino , Repeticiones de Microsatélite , Mosaicismo , Mutación , Pancreatectomía , Resultado del Tratamiento
12.
J Med Genet ; 47(11): 752-9, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20685672

RESUMEN

BACKGROUND: Congenital hyperinsulinism (CHI) is characterised by an over secretion of insulin by the pancreatic ß-cells. This condition is mostly caused by mutations in ABCC8 or KCNJ11 genes encoding the SUR1 and KIR6.2 subunits of the ATP-sensitive potassium (K(ATP)) channel. CHI patients are classified according to their responsiveness to diazoxide and to their histopathological diagnosis (either focal, diffuse or atypical forms). Here, we raise the benefits/limits of the genetic diagnosis in the clinical management of CHI patients. METHODS: ABCC8/KCNJ11 mutational spectrum was established in 109 diazoxide-unresponsive CHI patients for whom an appropriate clinical management is essential to prevent brain damage. Relationships between genotype and radiopathological diagnosis were analysed. RESULTS: ABCC8 or KCNJ11 defects were found in 82% of the CHI cases. All patients with a focal form were associated with a single K(ATP) channel molecular event. In contrast, patients with diffuse forms were genetically more heterogeneous: 47% were associated with recessively inherited mutations, 34% carried a single heterozygous mutation and 19% had no mutation. There appeared to be a predominance of paternally inherited mutations in patients diagnosed with a diffuse form and carrying a sole K(ATP) channel mutation. CONCLUSIONS: The identification of recessively inherited mutations related to severe and diffuse forms of CHI provides an informative genetic diagnosis and allows prenatal diagnosis. In contrast, in patients carrying a single K(ATP) channel mutation, genetic analysis should be confronted with the PET imaging to categorise patients as focal or diffuse forms in order to get the appropriate therapeutic management.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Hiperinsulinismo Congénito/genética , Mutación , Canales de Potasio de Rectificación Interna/genética , Receptores de Droga/genética , Hiperinsulinismo Congénito/diagnóstico , Hiperinsulinismo Congénito/tratamiento farmacológico , Análisis Mutacional de ADN , Diazóxido/uso terapéutico , Resistencia a Medicamentos , Femenino , Genotipo , Humanos , Lactante , Recién Nacido , Masculino , Receptores de Sulfonilureas , Vasodilatadores/uso terapéutico
13.
Pediatr Blood Cancer ; 52(1): 55-9, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18816692

RESUMEN

BACKGROUND: Children with WT1 gene-related disorders such as Denys-Drash syndrome (DDS) and Frasier syndrome (FS) are at increased risk of Wilms tumor and end-stage renal disease. We investigated whether Wilms tumors in these patients displayed a specific phenotype or behavior and whether nephron-sparing surgery was beneficial. PROCEDURE: We retrospectively studied all patients with DDS, FS, or other WT1 mutations treated at our institutions between 1980 and 2007. RESULTS: We identified 20 patients, of whom 18 had benign or malignant tumors. Wilms tumors occurred in 15 patients, being unilateral in 10 and bilateral in 5 (20 tumors). Median age at Wilms tumor diagnosis was 9 months. No patients had metastases. According to the International Society of Pediatric Oncology Working Classification, there were 19 intermediate-risk tumors and one high-risk tumor; no tumor was anaplastic. In patients with nephropathy who underwent unilateral nephrectomy for Wilms tumor or nephron-sparing surgery for bilateral Wilms tumor, mean time to dialysis was 11 or 9 months, respectively. Other tumors included three gonadoblastomas (in two patients), one retroperitoneal soft-tissue tumor, and one transitional cell papilloma of the bladder. Two patients, both with stage I Wilms tumor, died from end-stage renal disease-related complications. The median follow-up time for the 18 survivors was 136 months (range, 17-224 months). CONCLUSION: Most Wilms tumors in children with WT1-related disorders were early-stage and intermediate-risk tumors, with a young age at diagnosis. In patients without end-stage renal disease, nephron-sparing surgery should be considered for delaying the onset of renal failure.


Asunto(s)
Síndrome de Denys-Drash/terapia , Síndrome de Frasier/terapia , Tumor de Wilms/terapia , Adolescente , Niño , Preescolar , Síndrome de Denys-Drash/complicaciones , Manejo de la Enfermedad , Síndrome de Frasier/complicaciones , Humanos , Fallo Renal Crónico/prevención & control , Nefrectomía , Estudios Retrospectivos , Tumor de Wilms/complicaciones , Adulto Joven
15.
J Clin Endocrinol Metab ; 93(12): 4941-7, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18796520

RESUMEN

CONTEXT: Focal forms of congenital hyperinsulinism are due to a constitutional heterozygous mutation of paternal origin in the ABCC8 gene, more often than the KCNJ11 gene, located in the 11p15.1 region. This mutation is associated with the loss of the maternally inherited 11p15.1 to 11p15.5 region in the lesion. We investigated the possible occurrence of a compensatory duplication of the paternal 11p15.1-11p15.5 region. MATERIALS AND METHODS: A combined immunohistochemistry and fluorescent in situ hybridization study on beta-cell interphase nuclei with probes covering two genes located in this region (ABCC8 and CDKN1C genes) was performed in four cases of focal forms of hyperinsulinism. RESULTS: beta-Cells in the lesions of four cases of focal congenital hyperinsulinism were diploid for chromosomes 11 and 13. The 11p15.1 to 11p15.2 and 11p15.4 to 11p15.5 regions containing ABCC8 and CDKN1C genes, respectively, were present with two copies. Loss of the maternal allele was confirmed in these focal lesions with microsatellite markers flanking the ABCC8 and CDKN1C genes, whereas a heterozygous mutation in the ABCC8 gene was inherited from the father. CONCLUSIONS: There is a duplication of the paternal allele on chromosome 11 in the focal forms of hyperinsulinism lesion. The paternal isodisomy observed rendered the beta-cells homozygous for ABCC8 mutation and harbored a K-channel defect in the lesion similar to that observed in diffuse forms of congenital hyperinsulinism.


Asunto(s)
Cromosomas Humanos Par 11/genética , Hiperinsulinismo/congénito , Hiperinsulinismo/genética , Disomía Uniparental/genética , Transportadoras de Casetes de Unión a ATP/genética , Alelos , Cromosomas Humanos Par 13/genética , ADN/biosíntesis , ADN/genética , Padre , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Recién Nacido , Células Secretoras de Insulina/metabolismo , Masculino , Repeticiones de Microsatélite , Ploidias , Canales de Potasio de Rectificación Interna/genética , Receptores de Droga/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Receptores de Sulfonilureas
16.
J Pediatr Adolesc Gynecol ; 21(4): 201-6, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18656074

RESUMEN

INTRODUCTION: The authors describe and discuss the clinical and therapeutic features of 40 ovarian torsions (OT) in children with its urgent treatment that has advanced in recent years. MATERIALS AND METHODS: A retrospective study of 40 cases of OT in 38 children under 16 years of age, excluding adnexal torsions in neonates. RESULTS: Abdominal and/or pelvic pain was the presenting symptom ; 8 of these children had pain between 2 to 9 months prior to surgery and 27/40 (67.5%) had associated vomiting. Before the procedure, ultrasound (US) diagnosed 29 ovarian lesions, related to 14 mature teratomas (MTE) and 10 cystadenomas (CA), one association of MTE and CA in the same ovary, 2 functional cysts and 2 malignant neoplasms. 19/40 torsions could benefit from conservative management. Eleven torsions occurred, 10/11 of these ovaries had an increased volume, and 5/11 had US evidence of small subcortical cysts. Three detorsions with incomplete removal of CA were followed by enlargement of the tumor and re-torsion in 2 of them. Five children had bilateral ovarian pathology which led to unilateral ovariectomy, while the other benefited from conservative treatment. CONCLUSIONS: In any girl presenting with abdominal pain, the diagnosis of an ovarian torsion must be considered. US is performed emergently, but only surgery, most often a laparoscopic procedure, assures diagnosis. The treatment of the torsion is an emergency and must be as conservative as possible in order to preserve the ovarian function. Bilateral torsions are not unusual.


Asunto(s)
Enfermedades del Ovario/cirugía , Neoplasias Ováricas/cirugía , Anomalía Torsional/cirugía , Adolescente , Niño , Preescolar , Femenino , Humanos , Recurrencia Local de Neoplasia/cirugía , Enfermedades del Ovario/complicaciones , Neoplasias Ováricas/complicaciones , Ovariectomía , Estudios Retrospectivos
17.
J Neuroendocrinol ; 20(9): 1058-66, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18624928

RESUMEN

Infectious diseases and the administration of bacterial lipopolysaccharide (LPS) result in decreased food intake and increased energy expenditure. Because the hypothalamic paraventricular nucleus (PVN) has pivotal roles in the regulation of energy homeostasis and expresses an anorexic peptide, cocaine- and amphetamine-regulated transcript (CART), we hypothesised that increased CART synthesis in this nucleus may contribute to LPS-induced changes in energy homeostasis. Therefore, we studied the effects of intraperitoneal administration of LPS on CART gene expression in the PVN by semiquantitative in situ hybridisation. LPS caused a rapid increase in CART mRNA levels in the PVN. One hour after treatment, the density of silver grains was increased by three-fold in the PVN, and remained elevated 3 h after treatment. Because the dorsal vagal complex, an important vegetative centre in the brainstem, is heavily innervated by CART-containing axons, we determined whether the retrograde tracer, cholera toxin B subunit (CTB), accumulates in CART neurons in the PVN following stereotaxic injection of the tracer into the dorsal vagal complex. One week after injection, CTB accumulated in CART neurons in the ventral, medial, and lateral parvocellular subdivisions of the PVN. In addition, LPS administration induced c-fos expression in a population of CART neurons in the PVN that project to the dorsal vagal complex. These data indicate that increased CART gene expression in neurons of PVN may contribute to LPS-induced anorexia, and suggest that this action may be mediated, at least in part, through a PVN-dorsal vagal complex pathway.


Asunto(s)
Metabolismo Energético/efectos de los fármacos , Homeostasis/efectos de los fármacos , Lipopolisacáridos/farmacología , Proteínas del Tejido Nervioso/genética , Neuronas/efectos de los fármacos , Núcleo Hipotalámico Paraventricular/efectos de los fármacos , Animales , Anorexia/inducido químicamente , Anorexia/genética , Endotoxinas/farmacología , Metabolismo Energético/genética , Regulación de la Expresión Génica/efectos de los fármacos , Homeostasis/genética , Masculino , Proteínas del Tejido Nervioso/metabolismo , Neuronas/metabolismo , Núcleo Hipotalámico Paraventricular/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Ratas Wistar
18.
Hum Mutat ; 29(7): 903-10, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18449898

RESUMEN

Currarino syndrome (CS) is a rare congenital malformation described in 1981 as the association of three main features: typical sacral malformation (sickle-shaped sacrum or total sacral agenesis below S2), hindgut anomaly, and presacral tumor. In addition to the triad, tethered cord and/or lipoma of the conus are also frequent and must be sought, as they may lead to severe complications if not treated. The HLXB9 gene, located at 7q36, is disease-causing. It encodes the HB9 transcription factor and interacts with DNA through a highly evolutionarily conserved homeodomain early in embryological development. Thus far, 43 different heterozygous mutations have been reported in patients fulfilling CS criteria. Mutation detection rate is about 50%, and reaches 90% in familial cases. Here, we report 23 novel mutations in 26 patients among a series of 50 index cases with CS, and review mutational reports published since the identification of the causative gene. Three cytogenetic anomalies encompassing the HLXB9 gene are described for the first time. Truncating mutations (frameshifts or nonsense mutations) represent 57% of those identified, suggesting that haploinsufficiency is the basis of CS. No obvious genotype-phenotype correlation can be drawn thus far. Genetic heterogeneity is suspected, since at least 19 of the 24 patients without HLXB9 gene mutation harbor subtle phenotypic variations.


Asunto(s)
Anomalías Múltiples/genética , Proteínas de Homeodominio/genética , Intestinos/anomalías , Sacro/anomalías , Factores de Transcripción/genética , Secuencia de Bases , Exones , Familia , Femenino , Genotipo , Proteínas de Homeodominio/fisiología , Humanos , Masculino , Mutación , Fenotipo , Síndrome , Factores de Transcripción/fisiología
19.
Best Pract Res Clin Endocrinol Metab ; 21(3): 351-65, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17875484

RESUMEN

Ambiguous genitalia of the newborn is the paradigm of a disorder of sex development that demands a multidisciplinary team approach to management. The problem is immediately apparent at birth. Abnormalities of the external genitalia sufficient to warrant genetic and endocrine studies occur in one in 4500 births. In recent decades there have been improvements in diagnosis and early management, particularly with respect to congenital adrenal hyperplasia, the commonest cause of ambiguous genitalia of the newborn. However, dissatisfaction with overall management remains. A Clinical Guidelines and Handbook for Parents generated by a partnership of health professionals and support groups is available on the internet. The professional societies representing paediatric endocrinology responded by organizing a consensus meeting on the management of intersex. This resulted in the publication of a Consensus Statement encompassing many aspects of management, extending from birth to adulthood.


Asunto(s)
Atención Integral de Salud/normas , Trastornos del Desarrollo Sexual , Diferenciación Sexual/genética , Hiperplasia Suprarrenal Congénita/diagnóstico , Hiperplasia Suprarrenal Congénita/epidemiología , Hiperplasia Suprarrenal Congénita/terapia , Niño , Atención Integral de Salud/ética , Atención Integral de Salud/organización & administración , Trastornos del Desarrollo Sexual/diagnóstico , Trastornos del Desarrollo Sexual/etiología , Trastornos del Desarrollo Sexual/psicología , Trastornos del Desarrollo Sexual/terapia , Femenino , Humanos , Recién Nacido , Masculino , Guías de Práctica Clínica como Asunto , Estudios Retrospectivos , Análisis para Determinación del Sexo/ética , Análisis para Determinación del Sexo/tendencias , Diferenciación Sexual/fisiología , Terminología como Asunto
20.
Am J Med Genet A ; 143A(8): 871-4, 2007 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-17352395

RESUMEN

The most frequent cause of ventriculomegaly is spina bifida when associated with Arnold-Chiari type II malformation. We report on a prenatal diagnosis of severe ventriculomegaly in association with spinal dysraphism that was indicative of a Currarino syndrome (CS) due to a c.584delA, p.H195fsX28 truncated mutation within the HLXB9 gene. Physiopathology of the ventriculomegaly is discussed in reference to the fetopathological examination and CS embryopathology. In the present case, prognosis was poor and pregnancy termination was authorized. However, such a decision may be controversial in fetuses with less severe malformations on sonographic examination, since mutations in the HLXB9 gene can predict neither the severity nor the long-term prognosis of the disease. Due to a lack of genotype-phenotype correlation and the broad variability of phenotype in heterozygotes, clinical and genetic investigations among relatives are mandatory in all HLXB9 gene mutation cases, to detect asymptomatic CS cases and to prevent the occurrence of severe complications.


Asunto(s)
Cardiopatías Congénitas/diagnóstico , Diagnóstico Prenatal , Disrafia Espinal/diagnóstico , Salud de la Familia , Femenino , Enfermedades Fetales/diagnóstico , Asesoramiento Genético , Pruebas Genéticas , Atrios Cardíacos/anomalías , Humanos , Recién Nacido , Embarazo , Resultado del Embarazo , Pronóstico , Síndrome
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