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Most teleost fishes exhibit a biphasic life history with a larval oceanic phase that is transformed into morphologically and physiologically different demersal, benthic, or pelagic juveniles. This process of transformation is characterized by a myriad of hormone-induced changes, during the often abrupt transition between larval and juvenile phases called metamorphosis. Thyroid hormones (TH) are known to be instrumental in triggering and coordinating this transformation but other hormonal systems such as corticoids, might be also involved as it is the case in amphibians. In order to investigate the potential involvement of these two hormonal pathways in marine fish post-embryonic development, we used the Malabar grouper (Epinephelus malabaricus) as a model system. We assembled a chromosome-scale genome sequence and conducted a transcriptomic analysis of nine larval developmental stages. We studied the expression patterns of genes involved in TH and corticoid pathways, as well as four biological processes known to be regulated by TH in other teleost species: ossification, pigmentation, visual perception, and metabolism. Surprisingly, we observed an activation of many of the same pathways involved in metamorphosis also at an early stage of the larval development, suggesting an additional implication of these pathways in the formation of early larval features. Overall, our data brings new evidence to the controversial interplay between corticoids and thyroid hormones during metamorphosis as well as, surprisingly, during the early larval development. Further experiments will be needed to investigate the precise role of both pathways during these two distinct periods and whether an early activation of both corticoid and TH pathways occurs in other teleost species.

Crustaceans' endocrinology is a vastly understudied area of research. The major focus of the studies on this topic to date has been on the molting cycle (and in particular, the role of crustacean hyperglycemic hormone (CHH)), as well as the role of other hormones in facilitating physiological phenotypic adjustments to salinity changes. Additionally, while many recent studies have been conducted on the acclimation and adaptation capacity of crustaceans to a changing environment, only few have investigated internal hormonal balance especially with respect to an endocrine response to environmental challenges. Consequently, our study aimed to identify and characterize endocrine components of acid–base regulation in the European green crab, Carcinus maenas. We show that both the biogenic amine octopamine (OCT) and the CHH are regulatory components of branchial acid–base regulation. While OCT suppressed branchial proton excretion, CHH seemed to promote it. Both hormones were also capable of enhancing branchial ammonia excretion. Furthermore, mRNA abundance for branchial receptors (OCT-R), or G-protein receptor activated soluble guanylate cyclase (sGC1b), are affected by environmental change such as elevated pCO2 (hypercapnia) and high environmental ammonia (HEA). Our findings support a role for both OCT and CHH in the general maintenance of steady-state acid–base maintenance in the gill, as well as regulating the acid–base response to environmental challenges that C. maenas encounters on a regular basis in the habitats it dwells in and more so in the future ocean. [ABSTRACT FROM AUTHOR]

Stevia rebaudiana (Bertoni) Bertoni is a plant known for its natural sweeteners and potential health benefits. Traditionally used to treat diabetes, its impact on cellular signaling proteins such as PKC is unknown. This study begins with examining a database to analyse publications related to S. rebaudiana. The objective was to identify its experimentally validated phytochemicals and biological targets and to perform network pharmacological analysis of gene-disease associations. The identified targets are subsequently validated using a mouse model for LPS-induced PKC phosphorylation assay on mouse macrophage cells. The effect of HPTLC-standardized S. rebaudiana extract was also evaluated using FACS, ELISA, and fluorescence microscopical analysis. A total of 32 unique phytochemicals were found to interact with three targeted proteins, including 5′-Adenosine Monophosphate (AMP)-activated protein kinase catalytic subunit alpha-2/beta-1/gamma-1, 1,3-beta-D-glucan synthase, and xanthine dehydrogenase/oxidase. Network analysis and molecular modelling also supported targeted lead's binding and inhibition with AMP-activated protein kinase. The LPS significantly enhanced the phosphorylation of PKC in both ex vivo and in vivo assays. The standardised extract, which contains Rebaudioside and Stevioside at 4.82% w/w and 20.12 % w/w, respectively, attenuated the phosphorylation of PKC, suppressed nitric oxide (NO) and reactive oxygen species (ROS). This study found that stevia extract inhibited PKC phosphorylation in macrophages induced by LPS. Additional research is necessary to understand the potential effects of S. rebaudiana in managing PKC-mediated disorders. This includes exploring the mechanisms by which S. rebaudiana may interact with PKC and the possible therapeutic implications for various health conditions associated with PKC dysregulation. [Display omitted] [ABSTRACT FROM AUTHOR]

The endocrine system plays a pivotal role in shaping the mechanisms that ensure successful reproduction. With over a million known insect species, understanding the endocrine control of reproduction has become increasingly complex. Some of the key players include the classic insect lipid hormones juvenile hormone (JH) and ecdysteroids, and neuropeptides such as insulin-like peptides (ILPs). Individual endocrine factors not only modulate their own target tissue but also play crucial roles in crosstalk among themselves, ensuring successful vitellogenesis and oogenesis. Recent advances in omics, gene silencing, and genome editing approaches have accelerated research, offering both fundamental insights and practical applications for studying in-depth endocrine signaling pathways. This review provides an updated and integrated view of endocrine factors modulating vitellogenesis and oogenesis in insect females. [ABSTRACT FROM AUTHOR]

Resumen: Introducción: Los niños con hipotiroidismo congénito (HC) están en riesgo de presentar déficit cognitivos sutiles, a pesar de tener un rendimiento intelectual global dentro de rangos normales. Estos déficits pueden ser consecuencia de condiciones inherentes a la enfermedad y a factores relacionados con el tratamiento. El presente estudio explora el efecto de las desviaciones del estado de eutiroidismo durante los primeros 3 años de vida en el rendimiento atencional durante la edad escolar. Métodos: Fueron evaluados 49 niños con HC diagnosticado y bajo tratamiento, de ellos 14 fueron niños (9,5 ± 2,8 años de edad) y 35 niñas (9,6 ± 2,6 años de edad). Se calculó el total de episodios de sobre, infra y normotratamiento a partir de los valores de TSH durante los primeros 3 años de vida (medidos a los 12, 18, 24, 30 y 36 meses de edad). Los niños fueron evaluados mediante una versión computarizada del Test de atención sostenida. Se calcularon los modelos lineales generales usando el índice de atención como variable dependiente y el género, la etiología y los episodios de sobre, infra y normotratamiento como independientes. Resultados: El número de episodios de sobretratamiento (TSH baja) se asoció a un peor rendimiento atencional en la edad escolar (p = 0,005, r = –0,45). Conclusión: Debe realizarse un seguimiento estrecho en los 3 primeros años en pacientes con HC para evitar no solo el hipotiroidismo, sino también los efectos adversos de episodios de hipertratamiento que pueden comprometer el procesamiento atencional en edad escolar. Abstract: Introduction: Children with congenital hypothyroidism (CH) are at risk of developing mild cognitive impairment despite normal overall intellectual performance. These deficits may be caused by disease-related and treatment-related factors. This study explores the impact of abnormal thyroid function during the first 3 years of life on attention performance at school age. Methods: We included 49 children diagnosed with CH and receiving treatment for the condition: 14 boys (mean age 9.5 ± 2.8 years) and 35 girls (9.6 ± 2.6 years). The number of episodes of normal, under-, and overtreatment were estimated based on TSH levels during their first 3 years of life (at 12, 18, 24, 30, and 36 months). Children were assessed using a computerised version of a Sustained attention test. General linear models were calculated with the attention index as the dependent variable and sex, aetiology, and number of episodes of normal, under-, and overtreatment as independent variables. Results: Higher numbers of episodes of overtreatment (low TSH level) were associated with poorer attention performance at school age (P = .005, r = –0.45). Conclusions: Children with CH should be monitored closely during the first 3 years of life in order to prevent not only hypothyroidism but also any adverse effects of overtreatment that may affect attentional function at school age.

To effectively improve the vehicle suspension dynamic performances, minimizing discomfort of passengers and realize vibration energy recovery, a new kind of electromagnetic hybrid suspension (EMHS) system with parallel structure of linear motor and solenoid valve shock absorber is put forward. The linear motor actuator can work at the active state for active control or energy-regenerative state for energy recovery, the solenoid valve shock absorber work at the semi-active state for damping control. Firstly, for the analysis of the hybrid suspension, a quarter dynamic model of EMHS is established. Meanwhile, the mathematical models of linear motor actuator and solenoid valve shock absorber are founded, respectively. Then, for the better suspension control effect based on fuzzy control strategy, a novel endocrine composite fuzzy control strategy is designed. By learning the biological endocrine hormone regulation mechanism, the endocrine control with long feedback and ultra-short feedback is designed. The control laws of the fuzzy controller and endocrine controller are, respectively, designed. Finally, the simulation analysis of suspension dynamic performances and energy-regenerative characteristics is done, respectively. At the same time, the bench test is carried out based on the rapid control prototype with dSPACE platform. The results show the control effect of endocrine composite fuzzy control is better than that of fuzzy control, which improves the dynamic performances. Moreover, part of vibration energy is recovered.

Most teleost fishes exhibit a biphasic life history with a larval oceanic phase that is transformed into morphologically and physiologically different demersal, benthic, or pelagic juveniles. This process of transformation is characterized by a myriad of hormone-induced changes, during the often abrupt transition between larval and juvenile phases called metamorphosis. Thyroid hormones (TH) are known to be instrumental in triggering and coordinating this transformation but other hormonal systems such as corticoids, might be also involved as it is the case in amphibians. In order to investigate the potential involvement of these two hormonal pathways in marine fish post-embryonic development, we used the Malabar grouper ( Epinephelus malabaricus ) as a model system. We assembled a chromosome-scale genome sequence and conducted a transcriptomic analysis of nine larval developmental stages. We studied the expression patterns of genes involved in TH and corticoid pathways, as well as four biological processes known to be regulated by TH in other teleost species: ossification, pigmentation, visual perception, and metabolism. Surprisingly, we observed an activation of many of the same pathways involved in metamorphosis also at an early stage of the larval development, suggesting an additional implication of these pathways in the formation of early larval features. Overall, our data brings new evidence to the controversial interplay between corticoids and thyroid hormones during metamorphosis as well as, surprisingly, during the early larval development. Further experiments will be needed to investigate the precise role of both pathways during these two distinct periods and whether an early activation of both corticoid and TH pathways occurs in other teleost species., Competing Interests: RH, NR, KM, PP, SM, HC, MI, VL, TR No competing interests declared, (© 2024, Huerlimann, Roux et al.)

Objective: We take the release of stress hormone cortisol as a part of an intermittent control feedback system in contrast to the existing continuous models. By modeling cortisol secretion as an impulsive system, we design an impulsive controller as opposed to a continuous controller for adjusting cortisol levels while maintaining the blood cortisol levels within bounds that satisfy circadian demand and cost constraints. Methods: We develop an analytical approach along with an algorithm for identifying both the timing and amplitude of the control. Results: The model and the algorithm are tested by two examples to illustrate that the proposed approach achieves impulsive control and that the obtained blood cortisol levels render the circadian rhythm and the ultradian rhythm consistent with the known physiology of cortisol secretion. Conclusions: The approach successfully achieves the desired circadian impulsive control, which has great potential to be used in personalizing the medications in order to control the cortisol levels optimally. Significance: This type of bioinspired intermittent controllers can be employed for designing noncontinuous controllers in treating Addisonian disease, which is caused by the adrenal deficiency. [ABSTRACT FROM AUTHOR]

Orchestration of endocrine factors modulates many biological and physiological events including feeding behaviour. Concomitantly occurring impacts by neuropeptides on food intake and visceral contraction imply endocrine communication among the bioactive neuropeptides, which will cause successful feeding behaviour in insects. A number of physiological studies have demonstrated that neuropeptides and peptide hormones are involved in regulating insect feeding behaviours. In particular, allatoregulatory peptides modulate both food intake and gut contraction. In addition, adipokinetic hormone and insulin-like peptides might be significant factors contributing to energy homeostasis. Harmonization of those factors may generate the innate feeding behaviour. In this review, we address the communication of those endocrine factors which may lead to a putative endocrine network to execute a nutritionally appropriate feeding behaviour in insects. [ABSTRACT FROM AUTHOR]

A career interest in thermoregulation research has included wide contrasts in the subjects of enquiry, extending from heat stroke to hypothermia, special investigations in many different purpose-built climatic chambers, laboratorybased biomedical studies together with hospital practice, and field work in tropical climates to physiological surveys on urban populations in temperate environments. The scientific process and need to focus on careful planning of experiments, using the most appropriate methods, selecting the right controls and eventually applying correct statistical analysis do not always follow a smooth transition, as illustrated in this account. The result of endeavour to resolve a human environmental problem, however, is greatly satisfying, and sometimes becomes a unique experience when the solution reveals new fundamental facts. [ABSTRACT FROM AUTHOR]

Cholecystokinin (CCK) is an important regulator of pancreatic enzyme secretion in adult mammals and teleosteans. Although some studies have focused on the interaction between CCK and trypsin in marine fish larvae, little is known about the circadian patterns of the regulatory mechanism involving these two digestive components. In this study, we took advantage of the characteristic change from a diurnal to a nocturnal feeding habit that occurs in Senegalese sole ( Solea senegalensis ) post-larvae, to conduct an experiment where larvae and postlarvae were submitted to three different feeding regimes from mouth opening: continuous feeding, diurnal feeding and nocturnal feeding. The aim was to establish different daily feeding scenarios to uncover the operating mechanisms of CCK and tryptic enzyme activity over the 24-hour cycle to better understand the regulation of digestion in developing fish larvae. Results show a prevalence of simultaneous and opposing trends of CCK level and tryptic activity as a function of the postprandial time. This finding supports the existence of a regulatory loop between these two digestive components in pre- and post-metamorphic Senegal sole larvae. In addition, CCK level was also modulated by the gut content, tending to be lower when the gut is full and higher when is being emptied. Furthermore, larvae were able to synchronize digestive functions to very different feeding regimes, although it seems to be important having a diurnal feeding phase during pre-metamorphic stages for a proper development. [ABSTRACT FROM AUTHOR]

Adipose tissue has long been regarded as an organ the sole purpose of which was to store excess energy as triglycerides, and release energy as free fatty acids, which itself is an essential self-defense system for survival during starvation. This point of view has now changed, fat tissue has emerged as an endocrine and secretory organ affecting more than one metabolic pathway. Its major endocrine function is secreting several hormones, notably leptin and adiponectin. Also, adipose tissue releases adipokines involved in inflammation and hemostasis: growth factors (TNFa, transforming growth factor-beta, nerve growth factor, VEGF), cytokines (IL-1b, IL-6, IL-10), chemokines (IL-8), acute-phase proteins (haptoglobin, se rum amyloid A) and prothrombotic factor (plasminogen activator inhibitor-1). This review aims to present some of the recent topics of selected adipokine research that may be of particular importance.

Cortisol is released to relay information to cells to regulate metabolism and reaction to stress and inflammation. In particular, cortisol is released in the form of pulsatile signals. This low-energy method of signaling seems to be more efficient than continuous signaling. We hypothesize that there is a controller in the anterior pituitary that leads to pulsatile release of cortisol, and propose a mathematical formulation for such controller, which leads to impulse control as opposed to continuous control. We postulate that this controller is minimizing the number of secretory events that result in cortisol secretion, which is a way of minimizing the energy required for cortisol secretion; this controller maintains the blood cortisol levels within a specific circadian range while complying with the first order dynamics underlying cortisol secretion. We use an l0-norm cost function for this controller, and solve a reweighed l1-norm minimization algorithm for obtaining the solution to this optimization problem. We use 4 examples to illustrate the performance of this approach: (i) a toy problem that achieves impulse control, (ii) two examples that achieve physiologically plausible pulsatile cortisol release, (iii) an example where the number of pulses is not within the physiologically plausible range for healthy subjects while the cortisol levels are within the desired range. This novel approach results in impulse control where the impulses and the obtained blood cortisol levels have a circadian rhythm and an ultradian rhythm that are in agreement with the known physiology of cortisol secretion. The proposed formulation is a first step in developing intermittent controllers for curing cortisol deficiency. This type of bio-inspired pulse controllers can be employed for designing non-continuous controllers in brain-machine interface design for neuroscience applications.

Cortisol is released to relay information to cells to regulate metabolism and reaction to stress and inflammation. In particular, cortisol is released in the form of pulsatile signals. This low-energy method of signaling seems to be more efficient than continuous signaling. We hypothesize that there is a controller in the anterior pituitary that leads to pulsatile release of cortisol, and propose a mathematical formulation for such controller, which leads to impulse control as opposed to continuous control. We postulate that this controller is minimizing the number of secretory events that result in cortisol secretion, which is a way of minimizing the energy required for cortisol secretion; this controller maintains the blood cortisol levels within a specific circadian range while complying with the first order dynamics underlying cortisol secretion. We use an ℓ0-norm cost function for this controller, and solve a reweighed ℓ1-norm minimization algorithm for obtaining the solution to this optimization problem. We use four examples to illustrate the performance of this approach: (i) a toy problem that achieves impulse control, (ii) two examples that achieve physiologically plausible pulsatile cortisol release, (iii) an example where the number of pulses is not within the physiologically plausible range for healthy subjects while the cortisol levels are within the desired range. This novel approach results in impulse control where the impulses and the obtained blood cortisol levels have a circadian rhythm and an ultradian rhythm that are in agreement with the known physiology of cortisol secretion. The proposed formulation is a first step in developing intermittent controllers for curing cortisol deficiency. This type of bio-inspired pulse controllers can be employed for designing non-continuous controllers in brain-machine interface design for neuroscience applications. [ABSTRACT FROM AUTHOR]

Vitellogenin (Vtg) is an important precursor yolk protein in egg-laying vertebrates, including fish. The 17β-oestradiol (E2) plays a crucial role in the Vtg synthesis; moreover, certain hormones can stimulate Vtg synthesis. We investigated the possible role of E2, carp recombinant growth hormone (cr GH), insulin (Ins), progesterone (P4) and 11-deoxycortisol (11- DOC) hormones in Vtg synthesis on primary juvenile Chalcalburnus tarichi hepatocyte culture. The amount of Vtg in the medium was measured at 2-day intervals using enzyme-linked immunosorbent assay (ELISA). The hepatocytes were maintained in culture for more than 2 weeks without the addition of serum components. Vitellogenin localization was visualized with the immunofluorescence method in E2-supplemented hepatocytes. Among hormones applied to the culture, only E2 had an influence on Vtg synthesis in a time-dependent manner, while cr GH, Ins, P4 and 11- DOC had no effect. However, in hepatocytes stimulated with E2 in combination with P4, a lower Vtg production was seen compared with Vtg produced when hepatocytes were stimulated with E2 alone. P4 proved to have potentiating effects on co-treatment with E2-induced Vtg production. As a result, E2 and P4 are the most important hormones for Vtg synthesis in juvenile C. tarichi hepatocyte culture. [ABSTRACT FROM AUTHOR]

Abstract: Improving the understanding of digestive physiology in first feeding larvae is a prerequisite for advancing diet formulations and feeding protocols. In marine fish larvae that lack a stomach at first-feeding trypsin represents the main proteolytic enzyme. CCK is one of the key regulators of digestive enzyme secretion in adult vertebrates and current knowledge suggests that it is also involved in early stages of teleosts, although this may vary between species. Here, we investigated the influence of Artemia and a commercial microdiet on the ontogenetic development of tryptic enzyme activity as an indicator for digestive capacity in first-feeding sea bass. In order to examine the regulation and feedback mechanisms in the digestive tract we followed the response of gut CCK and tryptic enzyme activity during a one-day observation depending on the feeding regime at 23days post hatch. Larvae fed the microdiet showed a higher tryptic enzyme activity, probably as an adaptation to the higher content in complex protein in the diet. The plant protein phytohemagglutinin (PHA), added to the microdiet as a potential stimulator for the digestive system, did not induce elevated tryptic enzyme activity nor was it beneficial for growth. This was possibly due to adverse effects of too high doses. We observed an endogenous rhythm of CCK over the day, independent of the dietary treatment or short-term fasting. Higher tryptic enzyme activity in larvae fed Artemia during the day might indicate a better stimulation by live prey in the digestive tract or the superiority of a discontinuous feeding schedule in this group. We suggest that a reduction in tryptic enzyme activity after several feeding events indicates a limit in diurnal digestive capacity. Sea bass larvae are apparently able to adapt to the feeding schedule by synchronizing the tryptic enzyme activity like adult fish. [Copyright &y& Elsevier]

Abstract: In order to maximize protein digestion, the release of enzymes into the gut lumen is closely controlled by a regulatory loop. Cholecystokinin (CCK) is among the enteric hormones that play a key role in the control of digestive enzyme secretion, but its role in first-feeding larvae is still unclear and may differ between species. However, in all marine fish larvae that have not developed a stomach by first-feeding, trypsin is the most important proteolytic enzyme. In order to examine the regulation and feedback mechanisms in the gut of larval cod, we therefore studied the interactions between cholecystokinin and tryptic enzyme activity following the administration of solutions containing test substances directly into the gut. We tube-fed a single dose of physiological saline solution containing either CCK, CCK antagonist, trypsin inhibitor, phytohemagglutinin (PHA; a possible trigger for the digestive response) or physiological saline alone, while a further control group was left untreated. We then followed the response in CCK and tryptic enzyme activity for 0.5–8h after the administration. We performed the experiment on larvae at 26day post first-feeding, which is before the stomach has evolved and the size of the larvae allows easier handling. Individual larvae were analyzed for CCK and tryptic enzyme activity using radioimmunoassay and fluorimetric techniques respectively. Both factors varied over time in the untreated control group, possibly due to an endogenous daily rhythm. The higher CCK levels at 4h and 8h in the saline-injected group may be caused by reflexes initiated by distension of the gut. An increase in tryptic enzyme activity after injection of CCK supports the hypothesis that this hormone plays a part in the release of pancreatic enzymes in larval cod at this developmental stage. However, administration of a CCK antagonist and a trypsin inhibitor did not reveal conclusive results, probably due to the relatively low concentrations used. The response in tryptic activity in the PHA group was similar to the administration of CCK, pointing towards a stimulatory effect of PHA on the proteolytic enzyme capacity of cod larvae. [Copyright &y& Elsevier]

Abstract: The ontogenetic development of the gut hormone cholecystokinin (CCK) and the key proteolytic enzyme trypsin was described in Atlantic cod larvae (Gadus morhua) from first-feeding until 38days post first-feeding (dpff). CCK is known to play a major role in the endocrine control of digestive processes in mammals and adult fish, but its regulatory role in the larval stages of marine fish is largely unknown. Only small amounts of CCK were found in the body (excluding head) in cod larvae at first-feeding, but CCK levels increased exponentially with development, suggesting a more pronounced role of CCK during ontogeny. Tryptic enzyme activity increased slightly until a standard length of ca. 8mm (approx. 33days dpff) with a significant increase in larvae larger than 8mm standard length, indicating limited digestive capacity in the early stages. To entangle the short-term feedback mechanism between CCK and tryptic enzyme activity, we conducted a 12hour feeding experiment at 21 dpff. Cod larvae receiving only algae revealed a noticeable response in tryptic enzyme activity within two hours in the morning, whereas larvae fed algae and rotifers at the same time showed a slightly delayed response up to four hours. Tryptic enzyme activity remained low in the group receiving only algae as well as the two fed groups in the afternoon. No reaction in tryptic enzyme activity was observed in larvae that received a second meal of rotifers in the afternoon, indicating limited regulatory and digestive capacity to handle several meals in a short period. CCK levels remained relatively constant throughout the day but increased in the afternoon in all three groups when tryptic enzyme activity was low, suggesting that a negative feedback mechanism between CCK and tryptic enzyme activity is present in larval cod at least from 21 dpff. [Copyright &y& Elsevier]

The article presents a study which evaluates the timing of the adult remigial wing molt in female Branta Bernicla Nigricans Black Brant. The study used the data collected from 1992-2008 to evaluate the hypotheses on the role of molt completion and advantages in depleted nutrient reserve restoration in the prebasic molt initiation by Black Brant. Results suggest the advantage of greater volume of stored nutrient levels before the occurrence of molt initiation.

Background/Aims: Contradictory results regarding the optimal initial dose of levothyroxine in children with congenital hypothyroidism (CH) hamper the clinical management of these children during their early infancy. We explore the relationships between the initial dose of levothyroxine and endocrine control during the first 6 months and cognition at school age. Subjects and Methods: Fifty children with CH, 14 boys (10 ± 3.1 years) and 36 girls (9.7 ± 2.6 years), at the Pediatric Endocrine Unit of the Hospital Gregorio Marañón in Madrid were studied. Neurocognitive evaluation was carried out exploring alertness and inhibitory control. The number of episodes of overtreatment during the first 6 months, the initial dose of levothyroxine, etiology and sex were the predictor variables. Results: Inhibitory control was significantly lower in children with CH than in controls. An interaction with gender and etiology was obtained. Alertness had an inverse relationship with the number of episodes of overtreatment with no interaction with gender or etiology. Conclusion: Episodes of overtreatment and not the initial dose of levothyroxine are a risk factor for deficit in alertness whereas subtle inhibitory control deficit seems to be a permanent problem with the current therapeutic approach. [ABSTRACT FROM AUTHOR]

The article examines the hormonal and metabolic effects of dietary supplements on athletes. Some of the adverse effects of the intake of protein supplements include higher urea/nitrogen load on the kidneys and liver, gout, calcium loss and weight loss. It relates the possible impact of amino acid supplements on basal and stress related hormone levels. It emphasizes that there is no scientific evidence that the use of vitamin and mineral supplementation in young athletes has beneficial effects.

A significant component of aquaculture is the production of good quality larvae, and, in the case of flatfish, this is tied up with the change from a symmetric larva to an asymmetric juvenile. Despite the pioneering work carried out on the metamorphosis of the Japanese flounder (Paralichthys olivaceus) and summer flounder (Paralichthys dentatus), the underlying molecular basis of flatfish metamorphosis is still relatively poorly characterized. It is a thyroid hormone (TH) driven process, and the role of other hormones in the regulation of the process along with the interplay of abiotic factors are still relatively poorly characterized as is the extent of tissue and organ remodeling, which underlie the profound structural and functional modifications that accompany the larval/juvenile transition. The isolation of genes for hormones, receptors, binding proteins, and other accessory factors has provided powerful tools with which to pursue this question. The application of molecular methodologies such as candidate gene approaches and microarray analysis coupled to functional genomics has started to contribute to understanding the complexity of tissue and organ modifications that accompany flatfish metamorphosis. A better understanding of the biology of normal metamorphosis is essential to identify factors contributing to abnormal metamorphosis. [ABSTRACT FROM AUTHOR]

Abstract: The flightless bug Pyrrhocoris apterus (L.) is polymorphic for both wing length and flight muscle development. The developed flight muscles of macropterous adults of both sexes first enlarge their volume during the first 5 days after adult emergence, but are then histolyzed in all males and females older than 10 and 14 days, respectively. The flight muscles of brachypterous adult males and females are underdeveloped due to their arrested growth. The total protein content of histolyzed dorsolongitudinal flight muscles from 21-day-old macropterous adults of both sexes is lower than that of developed dorsolongitudinal flight muscles in 5–10-days-old macropterous bugs, but substantially higher than the protein content of underdeveloped dorsolongitudinal flight muscles from adult brachypters. Histolyzed dorsolongitudinal flight muscles differ from the developed ones by decreased quantities of 18 electrophoretically separated proteins. Histolysis of developed dorsolongitudinal flight muscles is accompanied by significant decreases in citrate synthase, glyceraldehyde-3-phosphate dehydrogenase and β-hydroxyacyl-CoA dehydrogenase enzyme activities and an increase in alanine aminotransferase activity, and can be precociously induced by application of a juvenile hormone analogue. This is the first report of flight muscle polymorphism, histolysis of developed flight muscles and its endocrine control in insects displaying non-functional wing polymorphism. [Copyright &y& Elsevier]