Changes in the central component of the hypothalamus-pituitary-thyroid axis in a rabbit model of prolonged critical illness

Introduction: Prolonged critically ill patients reveal low circulating thyroid hormone levels without a rise in thyroid stimulating hormone (TSH). This condition is labeled "low 3,5,3'-tri-iodothyronine (T3) syndrome" or "nonthyroidal illness syndrome (NTI)" or "euthyroid sick syndrome". Despite the low circulating and peripheral tissue thyroid hormone levels, thyrotropin releasing hormone (TRH) expression in the hypothalamus is reduced and it remains unclear which mechanism is responsible. We set out to study whether increased hypothalamic T3availability could reflect local thyrotoxicosis and explain feedback inhibition-induced suppression of the TRH gene in the context of the low T3syndrome in prolonged critical illness.Methods: Healthy rabbits were compared with prolonged critically ill, parenterally fed animals. We visualized TRH mRNA in the hypothalamus by in situ-hybridization and measured mRNA levels for the type II iodothyronine diodinase (D2), the thyroid hormone transporters monocarboxylate transporter (MCT) 8, MCT10 and organic anion co-transporting polypeptide 1C1 (OATP1C1) and the thyroid hormone receptors α (TRα) and β (TRβ) in the hypothalamus. We also measured the activity of the D2 and type III iodothyronine deiodinase (D3) enzymes.Results: In the hypothalamus of prolonged critically ill rabbits with low circulating T3 and TSH, we observed decreased TRH mRNA, increased D2 mRNA and increased MCT10 and OATP1C1 mRNA while MCT8 gene expression was unaltered as compared with healthy controls. This coincided with low hypothalamic thyroxine (T4) and low-normal T3concentrations, without a change at the thyroid hormone receptor level.Conclusions: Although expression of D2 and of the thyroid hormone transporters MCT10 and OATP1C1 were increased in the hypothalamus of prolonged critical ill animals, hypothalamic T4and T3content or thyroid hormone receptor expression were not elevated. Hence, decreased TRH gene expression, and hereby low TSH and T3 during prolonged critical illness, is not exclusively brought about by hypothalamic thyrotoxicosis, and infer other TRH suppressing factors to play a role

Impact of critical illness and withholding of early parenteral nutrition in the pediatric intensive care unit on long-term physical performance of children:a 4-year follow-up of the PEPaNIC randomized controlled trial

Background: Many critically ill children face long-term developmental impairments. The PEPaNIC trial attributed part of the problems at the level of neurocognitive and emotional/behavioral development to early use of parenteral nutrition (early-PN) in the PICU, as compared with withholding it for 1 week (late-PN). Insight in long-term daily life physical functional capacity after critical illness is limited. Also, whether timing of initiating PN affects long-term physical function of these children remained unknown. Methods: This preplanned follow-up study of the multicenter PEPaNIC randomized controlled trial subjected 521 former critically ill children (253 early-PN, 268 late-PN) to quantitative physical function tests 4 years after PICU admission in Leuven or Rotterdam, in comparison with 346 age- and sex-matched healthy children. Tests included handgrip strength measurement, timed up-and-go test, 6-min walk test, and evaluation of everyday overall physical activity with an accelerometer. We compared these functional measures for the former critically ill and healthy children and for former critically ill children randomized to late-PN versus early-PN, with multivariable linear or logistic regression analyses adjusting for risk factors. Results: As compared with healthy children, former critically ill children showed less handgrip strength (p &lt; 0.0001), completed the timed up-and-go test more slowly (p &lt; 0.0001), walked a shorter distance in 6 min (p &lt; 0.0001) during which they experienced a larger drop in peripheral oxygen saturation (p ≤ 0.026), showed a lower energy expenditure (p ≤ 0.024), performed more light and less moderate physical activity (p ≤ 0.047), and walked fewer steps per day (p = 0.0074). Late-PN as compared with early-PN did not significantly affect these outcomes. Conclusions: Four years after PICU admission, former critically ill children showed worse physical performance as compared with healthy children, without impact of timing of supplemental PN in the PICU. This study provides further support for de-implementing the early use of PN in the PICU. Trial registration ClinicalTrials.gov, NCT01536275; registered on February 22, 2012.</p

Intrahepatic cholestasis in subclinical and overt hyperthyroidism: two case reports

<p>Abstract</p> <p>Introduction</p> <p>Non-specific abnormalities in liver function tests might accompany the clinical course of hyperthyroidism. Hyperthyroidism can cause the elevation of hepatic enzymes and bilirubin. Jaundice is rare in overt hyperthyroidism, especially in subclinical hyperthyroidism. On the other hand, the use of anti-thyroid drugs has rarely been associated with toxic hepatitis and cholestatic jaundice.</p> <p>Case presentation</p> <p>Here we present two cases of cholestasis that accompanied two distinct forms of clinical hyperthyroidism. The first patient had a clinical presentation of severe cholestasis in the absence of congestive failure related to hyperthyroidism. The second case had developed intrahepatic cholestasis in the presence of subclinical hyperthyroidism, and improved with rifampicin treatment.</p> <p>Conclusion</p> <p>Hyperthyroidism should be a consideration in non-specific liver dysfunction.</p

The use of chemotherapy regimens carrying a moderate or high risk of febrile neutropenia and the corresponding management of febrile neutropenia: an expert survey in breast cancer and non-Hodgkin's lymphoma

The use of chemotherapy regimens with moderate or high risk of febrile neutropenia (defined as having a FN incidence of 10% or more) and the respective incidence and clinical management of FN in breast cancer and NHL has not been studied in Belgium. The existence of a medical need for G-CSF primary and secondary prophylaxis with these regimens was investigated in a real-life setting.Journal ArticleMulticenter StudyResearch Support, Non-U.S. Gov'tSCOPUS: ar.jinfo:eu-repo/semantics/publishe

American Thyroid Association Guide to Investigating Thyroid Hormone Economy and Action in Rodent and Cell Models

Background: An in-depth understanding of the fundamental principles that regulate thyroid hormone homeostasis is critical for the development of new diagnostic and treatment ap-proaches for patients with thyroid disease. Summary: Important clinical practices in use today for the treatment of patients with hypothy-roidism, hyperthyroidism, or thyroid cancer, are the result of laboratory discoveries made by scientists investigating the most basic aspects of thyroid structure and molecular biology. In this document, a panel of experts commissioned by the American Thyroid Association makes a se-ries of recommendations related to the study of thyroid hormone economy and action. These recommendations are intended to promote standardization of study design, which should in turn increase the comparability and reproducibility of experimental findings. Conclusions: It is expected that adherence to these recommendations by investigators in the field will facilitate progress towards a better understanding of the thyroid gland and thyroid hormone dependent processes

A microdissection technique for the « en face » visualisation of the human enteric nervous system

Les auteurs recommandent une méthode de visualisation "en face" de l'innervation intramurale du tractus digestif humain. La méthode comporte les étapes suivantes : fixation, microdissection, coloration des tissus nerveux et examen microscopique. Les échantillons d'organe entier, de segment tubulaire, ou de biopsie de petite taille obtenus par prélèvement chirurgical ou autopsie au départ de foetus, de nouveau-nés, et d'adultes sont manipulés « in toto » sans pratiquer de coupe. Après un étalement correct, ils sont fixés dans le fixateur de Pearson. Les différentes couches tissulaires de la paroi intestinale sont séparées par une microdissection précise sous contrôle stéréomicroscopique. Différentes méthodes de coloration des tissus nerveux peuvent être appliquées à ces feuillets tissulaires : histochimie enzymatique (acétylcholinestérases, NADPH-diaphorases), imprégnation argentique, et immunohistochimie (protéine S-100, protéine des neurofilaments, myéloprotéine basique). La topographie et la microanatomie des tissus colorés peuvent être investiguées par la stéréomicroscopie: les plexus ganglionnaires d'Auerbach, d'Henle et Meissner, les réseaux réticulaires des nerfs correspondant aux couches interne et externe de la muscutaris propria, la muqueuse musculaire, le tissu conjonctif de la sous-séreuse, la sous-muqueuse et la lamina propria. Après coloration des feuillets tissulaires,les structures neuromusculaires ayant un intérêt particulier et les éléments rares peuvent être enlevés et traités par les techniques de routine de la microscopie optique