Specific involvement of gonadal hormones in the functional maturation of growth hormone releasing hormone (GHRH) neurons

Growth hormone (GH) is the key hormone involved in the regulation of growth and metabolism, two functions that are highly modulated during infancy. GH secretion, controlled mainly by GH releasing hormone (GHRH), has a characteristic pattern during postnatal development that results in peaks of blood concentration at birth and puberty. A detailed knowledge of the electrophysiology of the GHRH neurons is necessary to understand the mechanisms regulating postnatal GH secretion. Here, we describe the unique postnatal development of the electrophysiological properties of GHRH neurons and their regulation by gonadal hormones. Using GHRH-eGFP mice, we demonstrate that already at birth, GHRH neurons receive numerous synaptic inputs and fire large and fast action potentials (APs), consistent with effective GH secretion. Concomitant with the GH secretion peak occurring at puberty, these neurons display modifications of synaptic input properties, decrease in AP duration, and increase in a transient voltage-dependant potassium current. Furthermore, the modulation of both the AP duration and voltage-dependent potassium current are specifically controlled by gonadal hormones because gonadectomy prevented the maturation of these active properties and hormonal treatment restored it. Thus, GHRH neurons undergo specific developmental modulations of their electrical properties over the first six postnatal weeks, in accordance with hormonal demand. Our results highlight the importance of the interaction between the somatotrope and gonadotrope axes during the establishment of adapted neuroendocrine functions

On primitive constant dimension codes and a geometrical sunflower bound

Altres ajuts: COST project Random Network Coding and Designs over GF(q) (COST IC-1104)In this paper we study subspace codes with constant intersection dimension (SCIDs). We investigate the largest possible dimension spanned by such a code that can yield non-sunflower codes, and classify the examples attaining equality in that bound as one of two infinite families. We also construct a new infinite family of primitive SCIDs

New Integrated High-Resolution Dinoflagellate Cyst Stratigraphy and Litho- and Chemostratigraphy from the Paris and Dieppe–Hampshire Basins for the “Sparnacian”

The Paris Basin represents an historical cradle of Palaeogene stratigraphy, where during the nineteenth century the Palaeocene Series and the “Sparnacian Stage” were established. As highlighted by Aubry et al. (2005), whereas the chronostratigraphic connotation of the “Sparnacian Stage” has been controversial since its definition, modern studies of the late Palaeocene–early Eocene interval have revealed that the so-called “Sparnacian” deposits encompass a remarkable and short (~170 kyr) episode of the Cenozoic, the Palaeocene–Eocene Thermal Maximum (PETM, ~55.8–55.6 Ma). Dinoflagellate assemblages from the “Sparnacian” of the Dieppe–Hampshire and Paris basins do not contain the key species Apectodinium augustum, whereas it is present in the northern Belgian Basin Tienen Formation and is coeval there with the CIE and the Apectodinium acme interval. However, our calibration of the Apectodinium acme to the CIE in the Dieppe–Hampshire and Paris basins suggests its attribution to the A. augustum zone. The absence of species A. augustum in the Anglo–Paris Basin may be explained by its restriction to more offshore conditions

Accelerated partial breast irradiation: the case for current use

The treatment of early stage breast cancer is evolving from traditional breast conservation techniques, employing conventionally fractionated whole breast irradiation, to techniques in which partial breast irradiation is used in an accelerated fractionation scheme. A growing body of evidence exists, including favorable findings. Additional studies are under way that may ultimately prove equivalence. The logic behind this approach is reviewed, and the currently available data are presented to support the current use of carefully applied partial breast irradiation techniques in appropriately selected and informed patients

Optimal clinical management of children receiving ketogenic parenteral nutrition: a clinical practice guide

AIM To give evidence-based recommendations on the application of ketogenic diet parenteral nutrition (KD-PN) in emergency situations. METHOD An international group of experts (n=14) researched the literature and distributed a survey among 150 expert centers. International accepted guidelines (European Society for Clinical Nutrition and Metabolism/European Society for Paediatric Gastroenterology Hepatology and Nutrition and the American Society for Parenteral and Enteral Nutrition) and handbooks for parenteral nutrition were considered general standards of care. RESULTS In the literature, we identified 35 reports of patients treated by KD-PN. International guidelines and handbooks provided some conflicting information. Twenty-four expert teams from nine countries responded to the survey, reflecting the limited clinical experience. INTERPRETATION This paper highlights 23 consensus-based recommendations for safe and effective KD-PN (e.g. diet initiation, calculation, application, monitoring, and evaluation) based on the best evidence available and expert opinions

Phase II study of helical tomotherapy in the multidisciplinary treatment of oligometastatic colorectal cancer

<p>Abstract</p> <p>Background</p> <p>Complete metastasectomy provides a real chance for long-term survival in patients with oligometastatic colorectal cancer (CRC). For inoperable patients, we evaluated in this study intensity-modulated and image-guided radiotherapy (IMRT-IGRT) by helical tomotherapy.</p> <p>Methods</p> <p>Twenty-four CRC patients with ≤ 5 metastases were enrolled, receiving a dose of 50 Gy in fractions of 5 Gy. No limitations concerning dimension or localization of the metastases were imposed. Whole body PET-CT was performed at baseline and 3 months after the initiation of RT to evaluate the metabolic response rate according to PET Response Criteria in Solid Tumors (PERCIST) version 1.0.</p> <p>Results</p> <p>A total of 53 metastases were treated. Seventeen patients (71%) received previously ≥ 1 line of chemotherapy for metastatic disease, displaying residual (n = 7) or progressive (n = 10) metabolic active oligometastatic disease at time of inclusion. Most common sites were the lung, liver and lymphnodes. One patient (4%) experienced grade 3 dysphagia. Twenty-two patients were evaluated by post-treatment PET-CT. Twelve patients achieved a complete (n = 6) or partial (n = 6) metabolic response, resulting in an overall metabolic response rate of 55%. At a median follow-up of 10 months, 7 patients (29%) are in remission, of which 5 received previous chemotherapy with residual oligometastatic disease at time of inclusion. The actuarial 1-year local control, progression-free survival, and overall survival were 54%, 14% and 78%.</p> <p>Conclusions</p> <p>Helical tomotherapy delivering 10 fractions of 5 Gy resulted in a metabolic response rate of 55%, and appeared to be attractive as consolidation of inoperable oligometastatic disease after effective chemotherapy.</p> <p>Trial registration</p> <p>Eudract 2008-008300-40; <a href="http://www.clinicaltrials.gov/ct2/show/NCT00807313">NCT00807313</a></p

Modeling the effect of age in T1-2 breast cancer using the SEER database

BACKGROUND: Modeling the relationship between age and mortality for breast cancer patients may have important prognostic and therapeutic implications. METHODS: Data from 9 registries of the Surveillance, Epidemiology, and End Results Program (SEER) of the United States were used. This study employed proportional hazards to model mortality in women with T1-2 breast cancers. The residuals of the model were used to examine the effect of age on mortality. This procedure was applied to node-negative (N0) and node-positive (N+) patients. All causes mortality and breast cancer specific mortality were evaluated. RESULTS: The relationship between age and mortality is biphasic. For both N0 and N+ patients among the T1-2 group, the analysis suggested two age components. One component is linear and corresponds to a natural increase of mortality with each year of age. The other component is quasi-quadratic and is centered around age 50. This component contributes to an increased risk of mortality as age increases beyond 50. It suggests a hormonally related process: the farther from menopause in either direction, the more prognosis is adversely influenced by the quasi-quadratic component. There is a complex relationship between hormone receptor status and other prognostic factors, like age. CONCLUSION: The present analysis confirms the findings of many epidemiological and clinical trials that the relationship between age and mortality is biphasic. Compared with older patients, young women experience an abnormally high risk of death. Among elderly patients, the risk of death from breast cancer does not decrease with increasing age. These facts are important in the discussion of options for adjuvant treatment with breast cancer patients

Long-COVID cognitive impairments and reproductive hormone deficits in men may stem from GnRH neuronal death

BACKGROUND: We have recently demonstrated a causal link between loss of gonadotropin-releasing hormone (GnRH), the master molecule regulating reproduction, and cognitive deficits during pathological aging, including Down syndrome and Alzheimer's disease. Olfactory and cognitive alterations, which persist in some COVID-19 patients, and long-term hypotestosteronaemia in SARS-CoV-2-infected men are also reminiscent of the consequences of deficient GnRH, suggesting that GnRH system neuroinvasion could underlie certain post-COVID symptoms and thus lead to accelerated or exacerbated cognitive decline. METHODS: We explored the hormonal profile of COVID-19 patients and targets of SARS-CoV-2 infection in post-mortem patient brains and human fetal tissue. FINDINGS: We found that persistent hypotestosteronaemia in some men could indeed be of hypothalamic origin, favouring post-COVID cognitive or neurological symptoms, and that changes in testosterone levels and body weight over time were inversely correlated. Infection of olfactory sensory neurons and multifunctional hypothalamic glia called tanycytes highlighted at least two viable neuroinvasion routes. Furthermore, GnRH neurons themselves were dying in all patient brains studied, dramatically reducing GnRH expression. Human fetal olfactory and vomeronasal epithelia, from which GnRH neurons arise, and fetal GnRH neurons also appeared susceptible to infection. INTERPRETATION: Putative GnRH neuron and tanycyte dysfunction following SARS-CoV-2 neuroinvasion could be responsible for serious reproductive, metabolic, and mental health consequences in long-COVID and lead to an increased risk of neurodevelopmental and neurodegenerative pathologies over time in all age groups. FUNDING: European Research Council (ERC) grant agreements No 810331, No 725149, No 804236, the European Union Horizon 2020 research and innovation program No 847941, the Fondation pour la Recherche Médicale (FRM) and the Agence Nationale de la Recherche en Santé (ANRS) No ECTZ200878 Long Covid 2021 ANRS0167 SIGNAL, Agence Nationale de la recherche (ANR) grant agreements No ANR-19-CE16-0021-02, No ANR-11-LABEX-0009, No. ANR-10-LABEX-0046, No. ANR-16-IDEX-0004, Inserm Cross-Cutting Scientific Program HuDeCA, the CHU Lille Bonus H, the UK Medical Research Council (MRC) and National Institute of Health and care Research (NIHR)