Gangliosides are major glycans on vertebrate nerve cells, and their metabolic disruption results in congenital disorders with marked cognitive and motor deficits. The sialyltransferase gene
is ...responsible for terminal sialylation of two prominent brain gangliosides in mammals, GD1a and GT1b. In this study, we analyzed the expression of calcium-binding interneurons in primary sensory (somatic, visual, and auditory) and motor areas of the neocortex, hippocampus, and striatum of
-null mice as well as
-null and
-double null. Immunohistochemistry with highly specific primary antibodies for GABA, parvalbumin, calretinin, and calbindin were used for interneuron detection.
-null mice had decreased expression of all three analyzed types of calcium-binding interneurons in all analyzed regions of the neocortex. These results implicate gangliosides GD1a and GT1b in the process of interneuron migration and maturation.
Lipid rafts, specialised microdomains within cell membranes, play a central role in orchestrating various aspects of neurodevelopment, ranging from neural differentiation to the formation of ...functional neuronal networks. This review focuses on the multifaceted involvement of lipid rafts in key neurodevelopmental processes, including neural differentiation, synaptogenesis and myelination. Through the spatial organisation of signalling components, lipid rafts facilitate precise signalling events that determine neural fate during embryonic development and in adulthood. The evolutionary conservation of lipid rafts underscores their fundamental importance for the structural and functional complexity of the nervous system in all species. Furthermore, there is increasing evidence that environmental factors can modulate the composition and function of lipid rafts and influence neurodevelopmental processes. Understanding the intricate interplay between lipid rafts and neurodevelopment not only sheds light on the fundamental mechanisms governing brain development but also has implications for therapeutic strategies aimed at cultivating neuronal networks and addressing neurodevelopmental disorders.
The study aimed to determine the effectiveness of early antidiabetic therapy in reversing metabolic changes caused by high-fat and high-sucrose diet (HFHSD) in both sexes.
Elderly Sprague-Dawley ...rats, 45 weeks old, were randomized into four groups: a control group fed on the standard diet (STD), one group fed the HFHSD, and two groups fed the HFHSD along with long-term treatment of either metformin (HFHSD+M) or liraglutide (HFHSD+L). Antidiabetic treatment started 5 weeks after the introduction of the diet and lasted 13 weeks until the animals were 64 weeks old.
Unexpectedly, HFHSD-fed animals did not gain weight but underwent significant metabolic changes. Both antidiabetic treatments produced sex-specific effects, but neither prevented the onset of prediabetes nor diabetes.
Liraglutide vested benefits to liver and skeletal muscle tissue in males but induced signs of insulin resistance in females.
Kompetencija podrazumijeva sposobnost ili stručnost pojedinca za uspješno ovladavanje različitih ciljeva. Razlikuju se opće kompetencije, prenosive i neovisne o profesiji, i specifične kompetencije ...koje su profesionalno ovisne. Svaki pojedinac djeluje u svojem osobnom ili profesionalnom životu koristeći se jednima i drugima. Nastavnicima za obavljanje njihova posla potrebne su brojne kompetencije koje se u radu jednim imenom nazivaju pedagoškim kompetencijama koje, kao i ostale kompetencije, nisu statične i ne mogu se u potpunosti steći tijekom inicijalnog obrazovanja, nego su vrlo dinamične i razvijaju se cijelog života. U radu je predloženo i raspravljeno kako nastavnici tijekom svojega svakodnevnog rada mogu planirati i pratiti vlastiti razvoj pedagoških kompetencija ne bi li bili pasivni sudionici vlastitoga profesionalnog razvoja. Predložen je model ponavljajućih refleksija tijekom kojih se prikupljaju povratne informacije o učinkovitosti razvoja i utvrđivanja novih potreba za daljnji razvoj.
Competence implies the ability or expertise of an individual to successfully master a variety of goals. There are general competences that are transferrable and profession independent, and specific, ...profession dependent competences. Everyone uses both specific and general competences in their personal and professional life. Teachers need numerous competences to be able to do their job, and these are called pedagogical competences. Pedagogical competences, like other competences, are not static and cannot fully be acquired during professional education. Moreover, they are dynamic and require a lifetime of dedication, development, and growth. This paper discusses and suggests methods for teachers to monitor and plan the development of pedagogical competences in their everyday work so as not to become passive observers in their professional growth. The paper suggests a model of iterative reflections that gather feedback on the effectiveness of development and identifies novel requirements for continuous development.
Mono-, di- and trisialo gangliosides are major glycosphingolipids in the brain of higher vertebrates involved in lipid raft assembly. In contrast, the fish brain is abundant in ...polisialo-gangliosides, whose function is implicated in the modulation of repulsive and attractive intercellular interactions during embryonic development and a temperature adaptation process. The histological distribution of gangliosides is usually studied in rodent and mammalian brains, but to date it has not been described in the case of fish brain.
Gangliosides were extracted from adult brains of trout, carp and zebrafish and separated by TLC. High-affinity anti-ganglioside (GM1, GD1a, GD1b, GT1b) IgG antibodies were used for immunohistochemistry.
In trout and carp brains GM1 and GT1b are expressed in the same neuronal cell bodies from the telencephalon to the spinal cord. In zebrafish brain GM1 was not detected, whereas GT1b is a general neuropil staining. GD1a is specific for unmyelinated parallel fibers in carp and zebrafish brains as well as parallel fibers in the molecular layer of all cerebellar divisions. In trout brain GD1b is found in parallel fibers of the cerebellum, but not in the tectum mesencephali. GD1b is expressed in zebrafish neuronal cell bodies.
Each studied species has a different expression of complex gangliosides. GT1b is widely present, whereas GD1a and GD1b appear in a specific group of unmyelinated fibers and could be used as their specific marker.
This is the first report on mono-, di- and trisialo ganglioside (GM1, GD1a, GD1b and GT1b) distribution in the brain of adult Actinopterygian fishes. This article is part of a Special Issue entitled Glycoproteomics.
► Different Actinopterygian species show different complex ganglioside distributions. ► GD1a and GD1b appear on a specific group of unmyelinated fibers. ► GM1 and GT1b are specific for neuronal cell bodies in fish brain. ► The pattern found in GD1a and GD1b is not consistent in all three fish species.
Teachers must enhance their teaching skills in accordance with institutional policies at higher education institutions. This research aims to determine effective professional development techniques ... for biology teachers in higher education. The modified OZON form (cro. obrazac za opažanje nastave, teaching observation form) facilitated self-reflection and assessed the impact of reflection-based actions on the learning environment. Teachers participated in workshops, experiencing both student and curriculum-designer roles. Proficiency in creating an engaging learning environment and using technology was well developed. However, teachers should improve their understanding of curricular aspects, constructive alignment, outcome-driven selection of activities and formative and summative evaluation. Our research suggests modifying professional learning strategies to align with biology teachers' needs in higher education. Combining extended learning time, implementation in teaching practice, ongoing expert support, and action research fosters positive changes in a constructively aligned classroom. The results indicate that biology teachers in higher education need the continuous support of experts in the didactic design of the lesson plan to improve the creation of a learning environment through positive alignment. This approach promotes active professional development management in a concise format.
To evaluate the changes in the expression level of gonadal steroid, insulin, and leptin receptors in the brain of adult Sprague-Dawley female rats due to ovariectomy and/or chronic stress.
...Sixteen-week-old ovariectomized and non-ovariectomized female Sprague-Dawley rats were divided in two groups and exposed to three 10-day-sessions of sham or chronic stress. After the last stress-session the brains were collected and free-floating immunohistochemical staining was performed using androgen (AR), progesterone (PR), estrogen-β (ER-β), insulin (IR-α), and leptin receptor (ObR) antibodies. The level of receptors expression was analyzed in hypothalamic (HTH), cortical (CTX), dopaminergic (VTA/SNC), and hippocampal regions (HIPP).
Ovariectomy downregulated AR in the hypothalamic satiety centers and hippocampus. It prevented or attenuated the stress-specific upregulation of AR in these regions. The main difference in stress response between non-ovariectomized and ovariectomized females was in PR level. Ovariectomized ones had increased PR level in the HTH, VTA, and HIPP. Combination of stressors pushed the hypothalamic satiety centers toward the rise of ObR and susceptibility to leptin resistance. When exposed to combined stressors, the HIPP, SNC and piriform cortex upregulated the expression of IR-α and the possibility to develop insulin resistance.
Ovariectomy exacerbates the effect of chronic stress by preventing gonadal receptor-specific stress response reflected in the up-regulation of AR in the satiety and hippocampal regions, while stress after ovariectomy usually raises PR. The final outcome of inadequate stress response is reflected in the upregulation of ObR in the satiety centers and IR-α in the regions susceptible to early neurodegeneration. We discussed the possibility of stress induced metabolic changes under conditions of hormone deprivation.
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