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Open access

Sarah Christine Sentis, Rebecca Oelkrug, and Jens Mittag

A normal thyroid status is crucial for body temperature homeostasis, as thyroid hormone regulates both heat loss and conservation as well as heat production in thermogenic tissues. Brown adipose tissue (BAT) is the major site of non-shivering thermogenesis and an important target of thyroid hormone action. Thyroid hormone not only regulates the tissue’s sensitivity to sympathetic stimulation by norepinephrine, but also the expression of uncoupling protein 1, the key driver of BAT thermogenesis. Vice versa, sympathetic stimulation of BAT triggers the expression of deiodinase type II, an enzyme that enhances local thyroid hormone availability and signaling. This review summarizes the current knowledge on how thyroid hormone controls BAT thermogenesis, aiming to dissect the direct actions of the hormone in BAT and its indirect actions via the central nervous system, browning of white adipose tissue or heat loss over body surfaces. Of particular relevance is the apparent dose dependency of the observed effects, as we find that minor or moderate changes in thyroid hormone levels often have different effects as compared to high pharmacological doses. Moreover, we conclude that the more recent findings require a reevaluation of older studies, as key aspects such as heat loss or central BAT activation may not have received the necessary attention during the interpretation of these early findings. Finally, we provide a list of what we believe are the most relevant questions in the field that to date are still enigmatic and require further studies.

Open access

Enora Le Roux, Florence Menesguen, Isabelle Tejedor, Marc Popelier, Marine Halbron, Pauline Faucher, Sabine Malivoir, Graziella Pinto, Juliane Léger, Stephane Hatem, Michel Polak, Christine Poitou, and Philippe Touraine

Objective

The transition from paediatric to adult medicine involves risks of poor patient outcomes and of significant losses of patients to follow up. The research aimed to analyse the implementation in an initial cohort of patients of a new programme of transition to adult care based on a case management approach.

Design

A longitudinal study of the case management approach to transition, initiated in a university hospital in France in September 2016.

Methods

Patients with the endocrine or metabolic disease diagnosed during childhood and transferred to adult care were included. The transition programme includes three steps based on case management: liaising with paediatric services, personalising care pathways, and liaising with structures outside the hospital (general practitioners, agencies in the educational and social sector).

Results

The cohort included 500 patients, with malignant brain tumour (n = 56 (11%)), obesity (n = 55 (11%)), type 1 diabetes (n = 54 (11%)), or other disease (n = 335 (67%)). Their median age at transfer was 19, and the sex ratio was 0.5. At median 21 months of follow-up, 439 (88%) had a regular follow-up in or outside the hospital, 47 (9%) had irregular follow-up (absence at the last appointment or no appointment scheduled within the time recommended), 4 had stopped care on doctor’s advice, 4 had died, 3 had moved, and 3 had refused care. The programme involved 9615 case management actions; 7% of patients required more than 50 actions. Patients requiring most support were usually those affected by a rare genetic form of obesity.

Conclusions

Case managers successfully addressed the complex needs of patients. Over time, the cohort will provide unprecedented long-term outcome results for patients with various conditions who experienced this form of transition.

Open access

Sondra O’Callaghan and Hanford Yau

Palliation of symptoms related to malignancy-associated hypercalcemia (MAH) is essential and clinically meaningful for patients, given the continued poor prognosis, with high morbidity and mortality associated with this disease process. Historically, agents have been temporizing, having no impact on patient morbidity nor survival. We suggest that cinacalcet can be an efficacious agent to be taken orally, reducing patients’ time in the hospital/clinic settings. It is well-tolerated and maintains serum calcium levels in the normal range, while targeted cancer treatments can be employed. This has a direct, major impact on morbidity. Maintaining eucalcemia can increase quality of life, while allowing targeted therapies time to improve survival. Given that our case (and others) showed calcium reduction in MAH, there is promising evidence that cinacalcet can be more widely employed in this setting. Future consideration should be given to studies addressing the efficacy of cinacalcet in calcium normalization, improvement of quality of life, and impact on survival in patients with MAH. Though the exact mechanism of action for cinacalcet’s reduction in calcium in this setting is not currently known, we can still afford patients the possible benefit from it.

Open access

Sirazum Choudhury, Tricia Tan, Katharine Lazarus, and Karim Meeran

The introduction of adrenocortical extract in 1930, improved life expectancy to between two and five years with further increases seen with the introduction of cortisone acetate from 1948. Most patients are now treated with synthetic hydrocortisone, and incremental advances have been made with optimisation of daily dosing and the introduction of multi-dose regimens. Today there remains a significant mortality gap between individuals with treated hypoadrenalism and the general population. It is unclear whether this gap is a result of glucocorticoid over-replacement, under-replacement or loss of the circadian and ultradian rhythm of cortisol secretion, with detrimental risk of excess glucocorticoid at later times in the day. The way forwards involves replacement of the diurnal cortisol rhythm with better glucocorticoid replacement regimens. The steroid profile produced by both prednisolone and dual-release hydrocortisone (Plenadren), provide a smoother glucocorticoid profile than standard oral multidose regimens of hydrocortisone and cortisone acetate. The individualisation of prednisolone doses and lower bioavailability of Plenadren offer reductions in total steroid exposure. Although there is emerging evidence of both treatments offering better cardiometabolic outcomes than standard glucocorticoid replacement regimens, there is a paucity of evidence involving very low dose prednisolone (2-4 mg daily) compared to the larger doses (~7.5 mg) historically used. Data from upcoming clinical studies on prednisolone will therefore be of key importance in informing future practice.

Open access

Ju-shuang Li, Tao Wang, Jing-jing Zuo, Cheng-nan Guo, Fang Peng, Shu-zhen Zhao, Hui-hui Li, Xiang-qing Hou, Yuan Lan, Ya-ping Wei, Chao Zheng, and Guang-yun Mao

Diabetic retinopathy (DR), the most common microvascular complication of diabetes and leading cause of visual impairment in adults worldwide, is suggested to be linked to abnormal lipid metabolism. The present study aims to comprehensively investigate the relationship between n-6 polyunsaturated fatty acids (PUFAs) and DR. This was a propensity score matching based case–control study, including 69 pairs of DR patients and type 2 diabetic patients without DR with mean age of 56.7 ± 9.2 years. Five n-6 PUFAs were determined by UPLC-ESI-MS/MS system. Principle component regression (PCR) and multiple conditional logistic regression models were used to investigate the association of DR risk with n-6 PUFAs depending on independent training and testing sets, respectively. According to locally weighted regression model, we observed obvious negative correlation between levels of five n-6 PUFAs (linoleic acid, γ-linolenic acid, eicosadienoic acid, dihomo-γ-linolenic acid and arachidonicacid) and DR. Based on multiple PCR model, we also observed significant negative association between the five n-6 PUFAs and DR with adjusted OR (95% CI) as 0.62 (0.43,0.87). When being evaluated depending on the testing set, the association was still existed, and PCR model had excellent classification performance, in which area under the curve (AUC) was 0.88 (95% CI: 0.78, 0.99). In addition, the model also had valid calibration with a non-significant Hosmer–Lemeshow Chi-square of 9.44 (P = 0.307) in the testing set. n-6 PUFAs were inversely associated with the presence of DR, and the principle component could be potential indicator in distinguishing DR from other T2D patients.

Open access

Malgorzata Oczko-Wojciechowska, Agnieszka Czarniecka, Tomasz Gawlik, Barbara Jarzab, and Jolanta Krajewska

Medullary thyroid cancer (MTC) is a rare thyroid malignancy, which arises from parafollicular C-cells. It occurs in the hereditary or sporadic form. Hereditary type is a consequence of activation of the RET proto-oncogene by germline mutations, whereas about 80% of sporadic MTC tumors harbor somatic, mainly RET or rarely RAS mutations. According to the current ATA guidelines, a postoperative MTC risk stratification and long-term follow-up are mainly based on histopathological data, including tumor stage, the presence of lymph node and/or distant metastases (TNM classification), and serum concentration of two biomarkers: calcitonin (Ctn) and carcinoembryonic antigen (CEA). The type of RET germline mutation also correlates with MTC clinical characteristics. The most common and the best known RET mutation in sporadic MTC, localized at codon 918, is related to a more aggressive MTC course and poorer survival. However, even if histopathological or clinical features allow to predict a long-term prognosis, they are not sufficient to select the patients showing aggressive MTC courses requiring immediate treatment or those, who are refractory to different therapeutic methods. Besides the RET gene mutations, there are currently no other reliable molecular prognostic markers. This review summarizes the present data of genomic investigation on molecular prognostic factors in medullary thyroid cancer.

Open access

Jing Zhang, Zhiyong Zhao, Li Dong, Tao Han, Guojin Zhang, Yuntai Cao, and Junlin Zhou

Introduction and aim

It is difficult to distinguish between non-functioning pituitary macroadenomas (NFPMAs) and sellar meningiomas because of their overlapping imaging manifestations on routine MRI, especially in cases of meningiomas growing into the saddle. Here, we aimed to differentiate between these two tumors using apparent diffusion coefficient (ADC) values and MRI characteristics.

Methods

A total of 60 NFPMA and 52 sellar meningioma cases confirmed by the pathological analysis were retrospectively reviewed. All patients were examined via routine MRI and diffusion-weighted imaging (DWI) before undergoing surgery. The clinical characteristics, MRI characteristics, and max ADC (ADCmax), average ADC (ADCmean), and minimum ADC (ADCmin) values were compared between the two tumors via Chi-square test and two sample t-tests. Receiver operating characteristic (ROC) curve and binary logistic regression analyses were conducted to determine the discrimination ability.

Results

The ADCmax, ADCmean, and ADCmin values were significantly higher in NFPMAs compared to sellar meningiomas (P < 0.001 for all). Among ADC values, ADCmax demonstrated good performance with an AUC of 0.896 (95% CI, 0.823–0.969) and accuracy of 88.7%. A cut-off value of 0.97 × 10−3 mm2/s was used for ADCmax for differentiation between tumors. A combination of ADCmax values and clinicoradiological features showed the best discrimination ability for differential diagnosis between the two tumors, with an AUC of 0.981 (95% CI, 0.958–1.000) and accuracy of 96.9%.

Conclusion

A combination of ADCmax and clinicoradiological features demonstrates good discrimination ability and high accuracy for differentiation between NFPMAs and sellar meningiomas, and is a potential quantitative tool to aid in the selection of surgical techniques.

Open access

Jasmin Asberger, Thalia Erbes, Markus Jaeger, Gerta Rücker, Claudia Nöthling, Andrea Ritter, Kai Berner, Ingolf Juhasz-Böss, and Marc Hirschfeld

Breast cancer (BC) represents the most common type of cancer in females worldwide. Endocrine therapy evolved as one of the main concepts in treatment of hormone-receptor positive BC. Current research focuses on the elucidation of tumour resistance mechanisms against endocrine therapy. In a translational in vitro approach, potential regulatory effects of clinically implemented BC anti-oestrogens on ERα, its coactivators DDX5, DDX17 and other DEADbox proteins as well as on the proliferation markers cyclin D1 and Ki67 were investigated on both the RNA and protein level. BC in vitro models for hormone-receptor positive (MCF-7, T-47D) and hormone-receptor negative cells (BT-20) were subjected to endocrine therapy. Anti-oestrogen-dependent expression regulation of target genes on the transcriptional and translational level was quantified and statistically assessed. Endocrine therapy decreases the expression levels of Ki67, cyclin D1 and ERα in hormone-receptor positive cells. In the hormone-receptor negative cells, the three parameters remained stable after endocrine therapy. Endoxifen triggers a downregulation of DDX5 and DDX23 in MCF-7 cells. Fulvestrant treatment downregulates the expression levels of all investigated DEADbox proteins in MCF-7 cells. In T-47D cells, endoxifen and fulvestrant lead to a decrease of all target gene expression levels. Interestingly, endocrine therapy affects DEADbox RNA expression levels in BT-20 cells, too. However, this result could only be confirmed for DDX1, immunocytologically. The investigated DEADbox proteins appear to correlate with the oestrogen-dependent tumourigenesis in hormone-receptor positive BC and show expression alterations after endocrine treatment.

Open access

Emanuelle Nunes-Souza, Mônica Evelise Silveira, Monalisa Castilho Mendes, Seigo Nagashima, Caroline Busatta Vaz de Paula, Guilherme Guilherme Vieira Cavalcante da Silva, Giovanna Silva Barbosa, Julia Belgrowicz Martins, Lúcia de Noronha, Luana Lenzi, José Renato Sales Barbosa, Rayssa Danilow Fachin Donin, Juliana Ferreira de Moura, Gislaine Custódio, Cleber Machado-Souza, Enzo Lalli, and Bonald Cavalcante de Figueiredo

Objective

Adaptive changes in DHEA and sulfated-DHEA (DHEAS) production from adrenal zona reticularis (ZR) have been observed in normal and pathological conditions. Here we used three different cohorts to assess timing differences in DHEAS blood level changes and characterize the relationship between early blood DHEAS reduction and cell number changes in women ZR.

Materials and methods

DHEAS plasma samples (n = 463) were analyzed in 166 healthy prepubertal girls before pubarche (<9 years) and 324 serum samples from 268 adult females (31.9–83.8 years) without conditions affecting steroidogenesis. Guided by DHEAS blood levels reduction rate, we selected the age range for ZR cell counting using DHEA/DHEAS and phosphatase and tensin homolog (PTEN), tumor suppressor and cell stress marker, immunostaining, and hematoxylin stained nuclei of 14 post-mortem adrenal glands.

Results

We confirmed that overweight girls exhibited higher and earlier DHEAS levels and no difference was found compared with the average European and South American girls with a similar body mass index (BMI). Adrenopause onset threshold (AOT) defined as DHEAS blood levels <2040 nmol/L was identified in >35% of the females >40 years old and associated with significantly reduced ZR cell number (based on PTEN and hematoxylin signals). ZR cell loss may in part account for lower DHEA/DHEAS expression, but most cells remain alive with lower DHEA/DHEAS biosynthesis.

Conclusion

The timely relation between significant reduction of blood DHEAS levels and decreased ZR cell number at the beginning of the 40s suggests that adrenopause is an additional burden for a significant number of middle-aged women, and may become an emergent problem associated with further sex steroids reduction during the menopausal transition.

Open access

Caishun Zhang, Junhua Yuan, Qian Lin, Manwen Li, Liuxin Wang, Rui Wang, Xi Chen, Zhengyao Jiang, Kun Zhu, Xiaoli Chang, Bin Wang, and Jing Dong

Ghrelin plays a pivotal role in the regulation of food intake, body weight and energy metabolism. However, these effects of ghrelin in the lateral parabrachial nucleus (LPBN) are unexplored. C57BL/6J mice and GHSR−/− mice were implanted with cannula above the right LPBN and ghrelin was microinjected via the cannula to investigate effect of ghrelin in the LPBN. In vivo electrophysiological technique was used to record LPBN glucose-sensitive neurons to explore potential udnderlying mechanisms. Microinjection of ghrelin in LPBN significantly increased food intake in the first 3 h, while such effect was blocked by [D-Lys3]-GHRP-6 and abolished in GHSR−/− mice. LPBN ghrelin microinjection also significantly increased the firing rate of glucose-excited (GE) neurons and decreased the firing rate of glucose-inhibited (GI) neurons. Additionally, LPBN ghrelin microinjection also significantly increased c-fos expression. Chronic ghrelin administration in the LPBN resulted in significantly increased body weight gain. Meanwhile, no significant changes were observed in both mRNA and protein expression levels of UCP-1 in BAT. These results demonstrated that microinjection of ghrelin in LPBN could increase food intake through the interaction with growth hormone secretagogue receptor (GHSR) in C57BL/6J mice, and its chronic administration could also increase body weight gain. These effects might be associated with altered firing rate in the GE and GI neurons.