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Neurons that connect mechanosensory hair cell receptors to the central nervous system derive from the otic vesicle from where otic neuroblasts delaminate and form the cochleovestibular ganglion (CVG). Local signals interact to promote this process, which is autonomous and intrinsic to the otic vesicle. We have studied the expression and activity of insulin-like growth factor-1 (IGF-1) during the formation of the chick CVG, focusing attention on its role in neurogenesis. IGF-1 and its receptor (IGFR) were detected at the mRNA and protein levels in the otic epithelium and the CVG. The function of IGF-1 was explored in explants of otic vesicle by assessing the formation of the CVG in the presence of anti-IGF-1 antibodies or the receptor competitive antagonist JB1. Interference with IGF-1 activity inhibited CVG formation in growth factor-free media, revealing that endogenous IGF-1 activity is essential for ganglion generation. Analysis of cell proliferation cell death, and expression of the early neuronal antigens Tuj-1, Islet-1/2, and G4 indicated that IGF-1 was required for survival, proliferation, and differentiation of an actively expanding population of otic neurobtasts. IGF-1 blockade, however, did not affect NeuroD within the otic epithelium. Experiments carried out on isolated CVG showed that exogenous IGF-1 induced cell proliferation, neurite outgrowth, and G4 expression. These effects of IGF-1 were blocked by JB1. These findings suggest that IGF-1 is essential for neurogenesis by allowing the expansion of a transit-amplifying neuroblast population and its differentiation into postmitotic neurons. IGF-1 is one of the signals underlying autonomous development of the otic vesicle. Keywords: Sensory organs; Ectodermal placodes; IGF-1; Neurogenesis; Otic vesicle autonomy; Cell proliferation; Cell differentiation; Cell survival

On the basis of a qualitative index (Daily Fire Risk) for the meteorological severity, a model for predicting the daily number of forest fires over a zone is developed. DFR is obtained for each day from (e,D) values, where a is the parameter of stability in the lowest atmospheric layer (850-700 hPa) and D is the saturation deficit at lowest level (850 hPa). Both a and D are evaluated at 00.00 UTC from radwindsonde data. Four types of day may be described: I, II, III and IV-type if a classification on (e, D) values is established. Very High fireactivity is associated with type-I days; High with Type-III; Low with type IV and Very Low with type-II days. As in the case of other qualitative indices, two days which present an identical index may register a very different number of forest fires. This is due to the fact that the fire activity on a day d does not depend exclusively upon meteorological parameters of the day d. A second question to consider is related to the prediction of the daily number of fires PNF(d). In this way, an initial hypothesis may be PNF(d) = PW(d) W(d), in which PW(d) and W(d) are the Past Weather and the (present) Weather for eachday d. If several considerations such as PW(d) = PW(d-1) are introduced, a working expression for the daily number of forest fires results. The results obtained confirm the utility of the model and, consequently, it should be used to establish correct antifire management. [ABSTRACT FROM AUTHOR]

Variation in offspring sex ratio, particularly in birds, has been frequently studied over the last century, although seldom using long-term monitoring data. In raptors, the cost of raising males and females is not equal, and several variables have been found to have significant effects on sex ratio, including food availability, parental age, and hatching order. Sex ratio differences between island populations and their mainland counterparts have been poorly documented, despite broad scientific literature on the island syndrome reporting substantial differences in population demography and ecology. Here, we assessed individual and environmental factors potentially affecting the secondary sex ratio of the long-lived Egyptian vulture Neophron percnopterus . We used data collected from Spanish mainland and island populations over a ca. 30-year period (1995-2021) to assess the effects of insularity, parental age, breeding phenology, brood size, hatching order, type of breeding unit (pairs vs. trios), and spatial and temporal variability on offspring sex ratio. No sex bias was found at the population level, but two opposite trends were observed between mainland and island populations consistent with the island syndrome. Offspring sex ratio was nonsignificantly female-biased in mainland Spain (0.47, n  = 1112) but significantly male-biased in the Canary Islands (0.55, n  = 499), where a male-biased mortality among immatures could be compensating for offspring biases and maintaining a paired adult sex ratio. Temporal and spatial variation in food availability might also have some influence on sex ratio, although the difficulties in quantifying them preclude us from determining the magnitude of such influence. This study shows that insularity influences the offspring sex ratio of the Egyptian vulture through several processes that can affect island and mainland populations differentially. Our research contributes to improving our understanding of sex allocation theory by investigating whether sex ratio deviations from parity are possible as a response to changing environments comprised by multiple and complexly interrelated factors., Competing Interests: The authors declare no conflict of interest., (© 2023 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

The liver is a main target tissue of the biguanide metformin which activates AMP-activated protein kinase (AMPK). We previously reported that administration of metformin glycinate showed a greater decrease of glycated hemoglobin A1c than a placebo in patients with type 2 diabetes mellitus (T2DM). In this study, we compared the effects of metformin hydrochloride, the oral antidiabetic drug of first choice, with those of metformin glycinate in hepatocytes from non-diabetic and diabetic mice and humans. Both formulations were equally potent regard to the reduction of basal and glucagon-induced glucose production and mRNA levels of gluconeogenic enzymes (Pck1 and G6pc) in hepatocytes from C57/Bl6 mice and humans. On the contrary, phosphorylation of AMPK and its substrate acetyl CoA carboxylase (ACC) was faster in hepatocytes treated with metformin glycinate. Likewise, we found stronger reduction in hepatocytes from obese/diabetic db/db mice of glucagon-induced glucose output and more sustained AMPK phosphorylation after treatment with metformin glycinate. Importantly, insulin sensitization regarding phosphorylation of AKT (Ser473) was enhanced in hepatocytes from db/db mice or humans pretreated with metformin glycinate. In conclusion, our data indicate that metformin glycinate may be an alternative therapy against insulin resistance during obesity and/or T2DM., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Tyrosine hydroxylase (TH) catalyzes the first step in catecholamines synthesis. We studied the impact of reduced TH in brown adipose tissue (BAT) activation. In adult heterozygous ( Th +/- ) mice, dopamine and noradrenaline (NA) content in BAT decreased after cold exposure. This reduced catecholaminergic response did not impair cold adaptation, because these mice induced uncoupling protein 1 (UCP-1) and maintained BAT temperature to a similar extent than controls ( Th +/+ ). Possible compensatory mechanisms implicated were studied. Prdm16 and Fgf21 expression, key genes in BAT activation, were elevated in Th +/- mice at thermoneutrality from day 18.5 of embryonic life. Likewise, plasma FGF21 and liver Fgf21 mRNA were increased. Analysis of endoplasmic reticulum (ER) stress, a process that triggers elevations in FGF21, showed higher phospho-IRE1, phospho-JNK, and CHOP in BAT of Th +/- mice at thermoneutrality. Also, increased lipolysis in BAT of cold-exposure Th +/- mice was demonstrated by increased phosphorylation of hormone-sensitive lipase (HSL), as well as diacylglycerol (DAG) and FFA content. Overall, these results indicate that the mild effects of Th haploinsufficiency on BAT function are likely due to compensatory mechanisms involving elevations in Fgf21 and Prdm16 and through adaptive changes in the lipid profile., (Copyright © 2018 Vázquez et al.)

Proinsulin was first identified as the primary translation product of the insulin gene in Donald Steiner's laboratory in 1967, and was the first prohormone to be isolated and sequenced. While its role as an insulin precursor has been extensively studied in the field of endocrinology, the bioactivity of the proinsulin molecule itself has received much less attention. Insulin binds to isoforms A and B of the insulin receptor (IR) with high affinity. Proinsulin, in contrast, binds with high affinity only to IR-A, which is present in the nervous system, among other tissues and elicits antiapoptotic and neuroprotective effects in the developing and postnatal nervous system. Proinsulin specifically exerts neuroprotection in the degenerating retina in mouse and rat models of retinitis pigmentosa (RP), delaying photoreceptor and vision loss after local administration in the eye or systemic (intramuscular) administration of an adeno-associated viral (AAV) vector that induces constitutive proinsulin release. AAV-mediated proinsulin expression also decreases the expression of neuroinflammation markers in the hippocampus and sustains cognitive performance in a mouse model of precocious brain senescence. We have therefore proposed that proinsulin should be considered a functionally distinct member of the insulin superfamily. Here, we briefly review the legacy of Steiner's research, the neural expression of proinsulin, and the tissue expression patterns and functional characteristics of IR-A. We discuss the neuroprotective activity of proinsulin and its potential as a therapeutic tool in neurodegenerative conditions of the central nervous system, particularly in retinal dystrophies.

Introduction: Healthy state depends on the appropriate function of the homeostatic systems (nervous, endocrine and immune systems) and the correct communication between them. The functional and redox state of the immune system is an excellent marker of health, and animals with premature immunosenescence show a shorter lifespan. Since catecholamines modulate the function of immune cells, the alteration in their synthesis could provoke immunosenescence. The social environment could be a strategy for modulating this immunosenescence., Aim: To determine if an haploinsufficiency of tyrosine hydroxylase (TH), the limiting enzyme of synthesis of catecholamines, may produce a premature immunosenescence and if this immunosenescence could be modulated by the social environment., Materials and Methods: Adult (9±1 months) male ICR-CD1 mice with deletion of a single allele (hemi-zygotic: HZ) of the tyrosine hydroxylase enzyme (TH-HZ) and wild-type (WT) mice were used. Animals were housed in four subgroups: WT>50% (in the cage, the proportion of WT mice was higher than 50% in relation to TH-HZ), WT<50%, TH-HZ<50% and TH-HZ>50%. Peritoneal leukocytes were collected and phagocytosis, chemotaxis and proliferation of lymphocytes in the presence of lipopolysaccharide were analyzed. Glutathione reductase and glutathione peroxidase activities as well as oxidized/reduced glutathione ratio were studied., Results: TH-HZ>50% mice showed a deteriorated function and redox state in leukocytes respect to WT>50% and similar to old mice. However, TH-HZ<50% animals had similar values to those found in WT<50% mice., Conclusion: The haploinsufficiency of TH generates premature immunosenescence, which appears to be compensated by living together with an appropriate number of WT animals., (Copyright © 2016 SEGG. Publicado por Elsevier España, S.L.U. All rights reserved.)

Catecholamines are essential for the maintenance of physiological homeostasis under basal and stress conditions. We aim to determine the impact of deletion of a single allele of the tyrosine hydroxylase (Th) gene might have on aging arterial pressure and life-span. We found that Th haploinsufficiency prevents age-associated increase of arterial pressure (AP) in mature adult mice, and it results in the extension of the half-life of Th-heterozygous (TH-HET) mice respect to their wild-type (WT) littermates. Heart performance was similar in both genotypes. To further investigate the lack of increase in AP with age in TH-HET mice, we measured the AP response to intra-peritoneal administration of substances involved in AP regulation. The response to acetylcholine and the basal sympathetic tone were similar in both genotypes, while norepinephrine had a greater pressor effect in TH-HET mice, which correlated with altered adrenoreceptor expression in blood vessels and the heart. Furthermore, sympatho-adrenomedular response to stress was attenuated in TH-HET mice. Plasma catecholamine levels and urine glucose increased markedly in WT but not in TH-HET mice after stress. Our results showed that TH-HET mice are resistant to age-associated hypertension, present a reduction in the sympathetic response to stress and display an extended half-life., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: Recent pandemics of influenza A H1N1pdm09 virus have caused severe illness, especially in young people. Very few studies on influenza A H1N1pdm09 in post-pandemic periods exist, and there is no information on the severity of both seasonal influenza A(H1N1) and A(H3N2) from the same season, adjusting for potential confounders, including vaccine., Methods and Results: We performed a retrospective observational study of adults hospitalized during the 2014 season with influenza A(H1N1) or A(H3N2). All patients underwent the same diagnostic and therapeutic protocol in a single hospital, including early Oseltamivir therapy. We included 234 patients: 146 (62.4%) influenza A(H1N1) and 88 (37.6%) A(H3N2). A(H1N1) patients were younger (p<0.01), developed more pneumonia (p<0.01), respiratory complications (p = 0.015), ARDS (p = 0.047), and septic shock (p = 0.049), were more frequently admitted to the ICU (p = 0.022), required IMV (p = 0.049), and were less frequently vaccinated (p = 0.008). After adjusting for age, comorbidities, time from onset of illness, and vaccine status, influenza A(H1N1) (OR, 2.525), coinfection (OR, 2.821), and no vaccination (OR, 3.086) were independent risk factors for severe disease., Conclusions: Hospitalized patients with influenza A(H1N1) were more than twice as likely to have severe influenza. They were younger and most had not received the vaccine. Our findings suggest that seasonal influenza A(H1N1) maintains some features of pandemic viruses, and recommend wider use of vaccination in younger adult high-risk patients., Competing Interests: The authors have declared that no competing interests exist.

Purpose: The induction of proinsulin expression by transgenesis or intramuscular gene therapy has been shown previously to retard retinal degeneration in mouse and rat models of retinitis pigmentosa (RP), a group of inherited conditions that result in visual impairment. We investigated whether intraocular treatment with biodegradable poly (lactic-co-glycolic) acid microspheres (PLGA-MS) loaded with proinsulin has cellular and functional neuroprotective effects in the retina., Methods: Experiments were performed using the Pde6brd10 mouse model of RP. Methionylated human recombinant proinsulin (hPI) was formulated in PLGA-MS, which were administered by intravitreal injection on postnatal days (P) 14 to 15. Retinal neuroprotection was assessed at P25 by electroretinography, and by evaluating outer nuclear layer (ONL) cellular preservation. The attenuation of photoreceptor cell death by hPI was determined by TUNEL assay in cultured P22 retinas, as well as Akt phosphorylation by immunoblotting., Results: We successfully formulated hPI PLGA-MS to deliver the active molecule for several weeks in vitro. The amplitude of b-cone and mixed b-waves in electroretinographic recording was significantly higher in eyes injected with hPI-PLGA-MS compared to control eyes. Treatment with hPI-PLGA-MS attenuated photoreceptor cell loss, as revealed by comparing ONL thickness and the number of cell rows in this layer in treated versus untreated retinas. Finally, hPI prevented photoreceptor cell death and increased AktThr308 phosphorylation in organotypic cultured retinas., Conclusions: Retinal degeneration in the rd10 mouse was slowed by a single intravitreal injection of hPI-PLGA-MS. Human recombinant proinsulin elicited a rapid and effective neuroprotective effect when administered in biodegradable microspheres, which may constitute a future potentially feasible delivery method for proinsulin-based treatment of RP.

Background: Current guidelines recommend monitoring the anesthetic depth of sedation during respiratory endoscopy by using clinical scales despite their subjective nature and the potential change in the level of sedation caused by frequent stimulation. Monitoring by means of the bispectral index (BIS) has shown its utility in reducing the use of drugs and their adverse events in general anesthesia, but evidence in prolonged sedation is insufficient., Objective: Our objective was to evaluate BIS in patients undergoing endobronchial ultrasound (EBUS)., Methods: A randomized cohort study of 90 patients with mediastinal lymph node involvement and/or lung or mediastinal lesions for whom EBUS was indicated, comparing the modified observer's assessment of alertness/sedation scale clinical evaluation (n = 45) versus the BIS evaluation (n = 45) of sedation with propofol-remifentanil, was conducted in order to evaluate the clinical parameters, doses used, adverse events, and tolerance of the procedure., Results: We found a shorter waking time and a significantly lower dose of total propofol in the BIS group. Significantly fewer overall adverse events were recorded in the BIS group and included desaturation, hypotension, and bradypnea. Tolerance was better in the BIS group. No significant differences were found in terms of cough, memory of the procedure, or the level of difficulty of EBUS on the part of the pulmonologists., Conclusions: BIS monitoring of sedation in EBUS makes it possible to reduce the dosage of propofol, thereby shortening the waking time and reducing adverse events. This form of monitoring should be taken into consideration in the future for systematic use in prolonged sedation, as in the case of EBUS., (© 2016 S. Karger AG, Basel.)