Publications by authors named "Valeria Castagna"

During development, inner hair cells (IHCs) in the mammalian cochlea are unresponsive to acoustic stimuli but instead exhibit spontaneous activity. During this same period, neurons originating from the medial olivocochlear complex (MOC) transiently innervate IHCs, regulating their firing pattern which is crucial for the correct development of the auditory pathway. Although the MOC-IHC is a cholinergic synapse, previous evidence indicates the widespread presence of gamma-aminobutyric acid (GABA) signaling markers, including presynaptic GABA receptors (GABAR).

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  • Cholesterol plays a crucial role in maintaining neuronal membrane integrity and proper function, and imbalances can lead to neurodegenerative diseases and age-related changes.
  • This study investigates cholesterol levels in the inner ear of young and aged mice, finding that levels decrease with age, linked to increased expression of the cholesterol enzyme CYP46A1.
  • Pharmacological activation of CYP46A1 with efavirenz reduces cholesterol in outer hair cells, negatively impacting hearing, but dietary phytosterol supplementation can help counteract this effect, suggesting a potential strategy for preventing hearing loss.
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The genetic bases underlying the evolution of morphological and functional innovations of the mammalian inner ear are poorly understood. Gene regulatory regions are thought to play an important role in the evolution of form and function. To uncover crucial hearing genes whose regulatory machinery evolved specifically in mammalian lineages, we mapped accelerated noncoding elements (ANCEs) in inner ear transcription factor (TF) genes and found that PKNOX2 harbors the largest number of ANCEs within its transcriptional unit.

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  • Aging is the leading cause of hearing loss, with age-related hearing loss (ARHL) first impacting speech comprehension, especially in noisy environments.
  • Research in mice shows that cochlear synaptic degeneration and hair cell loss occur with age, linked to changes in cholinergic receptors that affect auditory feedback.
  • Mice with enhanced nicotinic receptors maintained better cochlear function, indicating that boosting olivocochlear feedback may help prevent age-related hearing decline.
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  • The auditory system in mammals starts off immature at birth and matures through spontaneous activity in the inner ear, influenced by a brainstem efferent pathway.
  • Research using a mouse model with boosted medial efferent activity revealed smaller Wave III responses in auditory brainstem responses, indicating potential central dysfunction in auditory circuits.
  • The findings suggest that early cochlear efferent innervation is critical for refining auditory maps and synaptic transmission in the central auditory system, with disruptions seen when efferent function is genetically enhanced.
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The mammalian inner ear possesses functional and morphological innovations that contribute to its unique hearing capacities. The genetic bases underlying the evolution of this mammalian landmark are poorly understood. We propose that the emergence of morphological and functional innovations in the mammalian inner ear could have been driven by adaptive molecular evolution.

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  • - Cochlear synaptopathy, linked to loud noise exposure, leads to hidden hearing loss (HHL), affecting people's ability to understand speech in noisy situations, even without obvious changes in hearing sensitivity.
  • - This study compares two mouse models (a knock-out with reduced cholinergic activity and a knock-in with enhanced cholinergic activity) to see how the medial olivocochlear (MOC) system affects HHL after noise exposure.
  • - Results indicate that higher cholinergic activity helps protect against HHL and promotes the formation of new synapses in the inner ear, suggesting potential avenues for repairing damage from noise exposure.
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Aim: Bowlby's attachment intergenerational transmission theory suggests that a woman's attachment to her parents, particularly her mother, plays an important role in her future parenting. We studied whether there was any association between pregnant women's attachment to their baby before and after birth and their relationships with their mothers.

Methods: A longitudinal study was carried out in 2015 on 201 first-time mothers recruited in the maternity ward of the level two Misericordia e Dolce Hospital in Prato, Italy.

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Background: Social relationships provide individuals with a general sense of self-worth, psychological wellbeing, as well as allowing them access to resources during stressful periods and transitions in life. Pregnancy is a time of significant life change for every woman. The aim of this study was to verify the influence of social support perceived by mothers during pregnancy on the quality of their birth experience and post-partum depression.

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Sleeping sickness is a deadly disease that primarily affects sub-Saharan Africa and is caused by protozoan parasites of the Trypanosoma genus. Trypanosomes are purine auxotrophs and their uptake pathway has long been appreciated as an attractive target for drug design. Recently, one tight-binding competitive inhibitor of the trypanosomal purine-specific nucleoside hydrolase (IAGNH) showed remarkable trypanocidal activity in a murine model of infection.

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In this paper, we present the biochemical and biological evaluation of N-arylmethyl-substituted iminoribitol derivatives as potential chemotherapeutic agents against trypanosomiasis. Previously, a library of 52 compounds was designed and synthesized as potent and selective inhibitors of Trypanosoma vivax inosine-adenosine-guanosine nucleoside hydrolase (IAG-NH). However, when the compounds were tested against bloodstream-form Trypanosoma brucei brucei, only one inhibitor, N-(9-deaza-adenin-9-yl)methyl-1,4-dideoxy-1,4-imino-d-ribitol (UAMC-00363), displayed significant activity (mean 50% inhibitory concentration [IC(50)] +/- standard error, 0.

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