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Copyright of Codex Aquilarensis is the property of Fundacion Santa Maria la Real del Patrimonio Historico and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Inner ear hair cells form synapses with afferent terminals and afferent neurons carry signals as action potentials to the central nervous system. Efferent neurons have their origins in the brainstem and some make synaptic contact with afferent dendrites beneath hair cells. Several neurotransmitters have been identified that may be released from efferent terminals to modulate afferent activity. Dopamine is a candidate efferent neurotransmitter in both the vestibular and auditory systems. Within the cochlea, activation of dopamine receptors may reduce excitotoxicity at the inner hair cell synapse via a direct effect of dopamine on afferent terminals. Here we investigated the effect of dopamine on sodium currents in acutely dissociated vestibular afferent calyces to determine if dopaminergic signaling could also modulate vestibular responses. Calyx terminals were isolated along with their accompanying type I hair cells from the cristae of gerbils (P15-33) and whole cell patch clamp recordings performed. Large transient sodium currents were present in all isolated calyces; compared to data from crista slices, resurgent Na+ currents were rare. Perfusion of dopamine (100 μM) in the extracellular solution significantly reduced peak transient Na+ currents by approximately 20% of control. A decrease in Na+ current amplitude was also seen with extracellular application of the D2 dopamine receptor agonist quinpirole, whereas the D2 receptor antagonist eticlopride largely abolished the response to dopamine. Inclusion of the phosphatase inhibitor okadaic acid in the patch electrode solution occluded the response to dopamine. The reduction in calyx sodium current in response to dopamine suggests efferent signaling through D2 dopaminergic receptors may occur via common mechanisms to decrease excitability in inner ear afferents. [ABSTRACT FROM AUTHOR]

Objective: Disulfiram has been repurposed as a potential candidate to suppress various cancers. However, its anti‐tumor effects and molecular mechanisms of oral squamous cell carcinoma remain unclear. In this study, we aimed to assess the anti‐cancer activity and underlying mechanisms of disulfiram in the context of oral squamous cell carcinoma. Materials and Methods: We tested the cytotoxicity of disulfiram in oral squamous cell carcinoma using a 3D culture model and a PDX model. Cell proliferation, cell death, and related signaling pathways were evaluated. Mitochondrial DNA copy number, mitochondrial respiration, mitochondrial mass, and mitochondrial complexes were analyzed. Results: Disulfiram can induce excessive autophagy in oral squamous cell carcinoma cells as a result of OXPHOS deficiency. Disulfiram‐induced OPA1 degradation can impair the functional cristae structure, which results in a dramatic reduction in mitochondrial respiration capability as well as ATP production. Subsequently, energy deprivation leads to excessive autophagy through AMPK activation. In addition, exogenous ATP blocked the activation of AMPK and rescued disulfiram‐induced cell death. Conclusion: DSF targets mitochondrial inner membrane protein OPA1 to disturb the energy supply, triggering excessive autophagy, and cell death in OSCC. Our study suggests OPA1‐dependent ATP generation is pharmacologically targetable in OSCC treatment. [ABSTRACT FROM AUTHOR]

Inner ear hair cells form synapses with afferent terminals and afferent neurons carry signals as action potentials to the central nervous system. Efferent neurons have their origins in the brainstem and some make synaptic contact with afferent dendrites beneath hair cells. Several neurotransmitters have been identified that may be released from efferent terminals to modulate afferent activity. Dopamine is a candidate efferent neurotransmitter in both the vestibular and auditory systems. Within the cochlea, activation of dopamine receptors may reduce excitotoxicity at the inner hair cell synapse via a direct effect of dopamine on afferent terminals. Here we investigated the effect of dopamine on sodium currents in acutely dissociated vestibular afferent calyces to determine if dopaminergic signaling could also modulate vestibular responses. Calyx terminals were isolated along with their accompanying type I hair cells from the cristae of gerbils (P15-33) and whole cell patch clamp recordings performed. Large transient sodium currents were present in all isolated calyces; compared to data from crista slices, resurgent Na+ currents were rare. Perfusion of dopamine (100 μM) in the extracellular solution significantly reduced peak transient Na+ currents by approximately 20% of control. A decrease in Na+ current amplitude was also seen with extracellular application of the D2 dopamine receptor agonist quinpirole, whereas the D2 receptor antagonist eticlopride largely abolished the response to dopamine. Inclusion of the phosphatase inhibitor okadaic acid in the patch electrode solution occluded the response to dopamine. The reduction in calyx sodium current in response to dopamine suggests efferent signaling through D2 dopaminergic receptors may occur via common mechanisms to decrease excitability in inner ear afferents.

The quantitative relationship between angular head movement and semicircular canal function is most often referenced to the well-known torsion-pendulum model that predicts cupular displacement from input head acceleration. The foundation of this model can be traced back to Steinhausen's series of papers between 1927 and 1933 whereby he endeavored to document observations of cupular displacements that would directly infer movement of the endolymph resulting from angular rotation. He also was the first to establish the direct relationship between cupular displacement and compensatory eye movements. While the chronology of these findings, with their successes and pitfalls, are documented in Steinhausen's work, it reflects a fascinating journey that has been inaccessible to the non-German speaking community. Therefore, the present compilation of translations, with accompanying introduction and discussion, was undertaken to allow a larger component of the vestibular scientific community to gain insight into peripheral labyrinthine mechanics provided by this historical account.

The quantitative relationship between angular head movement and semicircular canal function is most often referenced to the well-known torsion-pendulum model that predicts cupular displacement from input head acceleration. The foundation of this model can be traced back to Steinhausen's series of papers between 1927 and 1933 whereby he endeavored to document observations of cupular displacements that would directly infer movement of the endolymph resulting from angular rotation. He also was the first to establish the direct relationship between cupular displacement and compensatory eye movements. While the chronology of these findings, with their successes and pitfalls, are documented in Steinhausen's work, it reflects a fascinating journey that has been inaccessible to the non-German speaking community. Therefore, the present compilation of translations, with accompanying introduction and discussion, was undertaken to allow a larger component of the vestibular scientific community to gain insight into peripheral labyrinthine mechanics provided by this historical account. [ABSTRACT FROM AUTHOR]

• Nestin is associated with pluripotency and is expressed in the inner ear. • A lineage-tracing model tracked nestin-expressing cells in early postnatal mice. • Nestin-expressing cells are mitotically active in cochlear and vestibular tissues. • Nestin-expressing cells did not facilitate hair cell regeneration after ablation. • Further research into the mitotic activity of nestin-expressing cells is warranted. Nestin expression is associated with pluripotency. Growing evidence suggests nestin is involved in hair cell development. The objective of this study was to investigate the morphology and role of nestin-expressing cells residing in the early postnatal murine inner ear. A lineage-tracing nestin reporter mouse line was used to further characterize these cells. Their cochleae and vestibular organs were immunostained and whole-mounted for cell counting. We found Nestin-expressing cells present in low numbers throughout the inner ear. Three morphotypes were observed: bipolar, unipolar, and globular. Mitotic activity was noted in nestin-expressing cells in the cochlea, utricle, saccule, and crista. Nestin-expressing cell characteristics were then observed after hair cell ablation in two mouse models. First, a reporter model demonstrated nestin expression in a significantly higher proportion of hair cells after hair cell ablation than in control cochleae. However, in a lineage tracing nestin reporter mouse, none of the new hair cells which repopulated the organ of Corti after hair cell ablation expressed nestin, nor did the nestin-expressing cells change in morphotype. In conclusion, Nestin-expressing cells were identified in the cochlea and vestibular organs. After hair cell ablation, nestin-expressing cells did not react to the insult. However, a small number of nestin-expressing cells in all inner ear tissues exhibited mitotic activity, supporting progenitor cell potential, though perhaps not involved in hair cell regeneration. [ABSTRACT FROM AUTHOR]

Vestibular afferent neurons convey information from hair cells in the peripheral vestibular end organs to central nuclei. Primary vestibular afferent neurons can fire action potentials at high rates and afferent firing patterns vary with the position of nerve terminal endings in vestibular neuroepithelia. Terminals contact hair cells as small bouton or large calyx endings. To investigate the role of Na+ currents (INa) in firing mechanisms, we investigated biophysical properties of INa in calyx-bearing afferents. Whole cell patch-clamp recordings were made from calyx terminals in thin slices of gerbil crista at different postnatal ages: immature [postnatal day (P)5-P8, young (P13-P15), and mature (P30-P45)]. A large transient Na+ current (INaT) was completely blocked by 300 nM tetrodotoxin (TTX) in mature calyces. In addition, INaT was accompanied by much smaller persistent Na+ currents (INaP) and distinctive resurgent Na+ currents (INaR), which were also blocked by TTX. ATX-II, a toxin that slows Na+ channel inactivation, enhanced INaP in immature and mature calyces. 4,9-Anhydro-TTX (4,9-ah-TTX), which selectively blocks Nav1.6 channels, abolished the enhanced INa in mature, but not immature, calyces. Therefore, Nav1.6 channels mediate a component of INaT and INaP in mature calyces, but are minimally expressed at early postnatal days. INaR was expressed in less than one-third of calyces at P6-P8, but expression increased with development, and in mature cristae INaR was frequently found in peripheral calyces. INaR served to increase the availability of Na+ channels following brief membrane depolarizations. In current clamp, the rate and regularity of action potential firing decreased in mature peripheral calyces following 4,9-ah-TTX application. Therefore, Nav1.6 channels are upregulated during development, contribute to INaT, INaP, and INaR, and may regulate excitability by enabling higher mean discharge rates in a subpopulation of mature calyx afferents. NEW & NOTEWORTHY Action potential firing patterns differ between groups of afferent neurons innervating vestibular epithelia. We investigated the biophysical properties of Na+ currents in specialized vestibular calyx afferent terminals during postnatal development. Mature calyces express Na+ currents with transient, persistent, and resurgent components. Nav1.6 channels contribute to resurgent Na+ currents and may enhance firing in peripheral calyx afferents. Understanding Na+ channels that contribute to vestibular nerve responses has implications for developing new treatments for vestibular dysfunction. [ABSTRACT FROM AUTHOR]

The mammalian vestibular epithelia exhibit a remarkably stereotyped organization featuring cellular characteristics under planar cell polarity (PCP) control. PCP mechanisms are responsible for the organization of hair cell morphologic polarization vectors, and are thought to be responsible for the postsynaptic expression of the calcium-binding protein calretinin that defines the utricular striola and cristae central zone. However, recent analyses revealed that subtle differences in the topographic expression of oncomodulin, another calcium-binding protein, reflects heterogeneous factors driving the subtle variations in expression. Calbindin represents a third calcium-binding protein that has been previously described to be expressed in both hair cells and afferent calyces in proximity to the utricular striola and crista central zone. The objective of the present investigation was to determine calbindin's topographic pattern of expression to further elucidate the extent to which PCP mechanisms might exert control over the organization of vestibular neuroepithelia. The findings revealed that calbindin exhibited an expression pattern strikingly similar to oncomodulin. However, within calyces of the central zone calbindin was colocalized with calretinin. These results indicate that organizational features of vestibular epithelia are governed by a suite of factors that include PCP mechanisms as well others yet to be defined. [ABSTRACT FROM AUTHOR]

The LIM homeodomain transcription factor Lmx1a shows a dynamic expression in the developing mouse ear that stabilizes in the non-sensory epithelium. Previous work showed that Lmx1a functional null mutants have an additional sensory hair cell patch in the posterior wall of a cochlear duct and have a mix of vestibular and cochlear hair cells in the basal cochlear sensory epithelium. In E13.5 mutants, Sox2-expressing posterior canal crista is continuous with an ectopic "crista sensory epithelium" located in the outer spiral sulcus of the basal cochlear duct. The medial margin of cochlear crista is in contact with the adjacent Sox2-expressing basal cochlear sensory epithelium. By E17.5, this contact has been interrupted by the formation of an intervening non-sensory epithelium, and Atoh1 is expressed in the hair cells of both the cochlear crista and the basal cochlear sensory epithelium. Where cochlear crista was formerly associated with the basal cochlear sensory epithelium, the basal cochlear sensory epithelium lacks an outer hair cell band, and gaps are present in its associated Bmp4 expression. Further apically, where cochlear crista was never present, the cochlear sensory epithelium forms a poorly ordered but complete organ of Corti. We propose that the core prosensory posterior crista is enlarged in the mutant when the absence of Lmx1a expression allows JAG1-NOTCH signaling to propagate into the adjacent epithelium and down the posterior wall of the cochlear duct. We suggest that the cochlear crista propagates in the mutant outer spiral sulcus because it expresses Lmo4 in the absence of Lmx1a. [ABSTRACT FROM AUTHOR]

The vestibular system relays information about head position via afferent nerve fibers to the brain in the form of action potentials. Voltage-gated Na+ channels in vestibular afferents drive the initiation and propagation of action potentials, but their expression during postnatal development and their contributions to firing in diverse mature afferent populations are unknown. Electrophysiological techniques were used to determine Na+ channel subunit types in vestibular calyx-bearing afferents at different stages of postnatal development. We used whole cell patch clamp recordings in thin slices of gerbil crista neuroepithelium to investigate Na+ channels and firing patterns in central zone (CZ) and peripheral zone (PZ) afferents. PZ afferents are exclusively dimorphic, innervating type I and type II hair cells, whereas CZ afferents can form dimorphs or calyx-only terminals which innervate type I hair cells alone. All afferents expressed tetrodotoxin (TTX)-sensitive Na+ currents, but TTX-sensitivity varied with age. During the fourth postnatal week, 200–300 nM TTX completely blocked sodium currents in PZ and CZ calyces. By contrast, in immature calyces [postnatal day (P) 5–11], a small component of peak sodium current remained in 200 nM TTX. Application of 1 μM TTX, or Jingzhaotoxin-III plus 200 nM TTX, abolished sodium current in immature calyces, suggesting the transient expression of voltage-gated sodium channel 1.5 (Nav1.5) during development. A similar TTX-insensitive current was found in early postnatal crista hair cells (P5–9) and constituted approximately one third of the total sodium current. The Nav1.6 channel blocker, 4,9-anhydrotetrodotoxin, reduced a component of sodium current in immature and mature calyces. At 100 nM 4,9-anhydrotetrodotoxin, peak sodium current was reduced on average by 20% in P5–14 calyces, by 37% in mature dimorphic PZ calyces, but by less than 15% in mature CZ calyx-only terminals. In mature PZ calyces, action potentials became shorter and broader in the presence of 4,9-anhydrotetrodotoxin implicating a role for Nav1.6 channels in firing in dimorphic afferents.

This article aims to provoke a reflection on the dialogue, with a view to concrete action, between two areas vital to the activity and life of the Church: Christian Education and Hermeneutics. The Church, which is very present in the ecclesial communities through the programs of biblical teaching developed by them, is best known in the context of the Theological Academy as a discipline, but still a pressing need to bring the Church closer to the biblical text, which, as a rule, its interpretation. In order to do so, it is necessary first to define, although succinctly, both areas, in order to understand their contributions and relevance to the Church, and then to draw the possible relationship between Christian Education through the work of the educator Christian, with Hermeneutics, and this in a concrete way. It is recognized that, in a sense, teaching the Scriptures, as well as the Christian truths stemming from these same Scriptures, is a hermeneutical doing. It requires a great deal of hermeneutical work. It is necessary to ask how this relation can be effected, and it is to this question that the present text aims to respond. [ABSTRACT FROM AUTHOR]

The vestibular system relays information about head position via afferent nerve fibers to the brain in the form of action potentials. Voltage-gated Na+ channels in vestibular afferents drive the initiation and propagation of action potentials, but their expression during postnatal development and their contributions to firing in diverse mature afferent populations are unknown. Electrophysiological techniques were used to determine Na+ channel subunit types in vestibular calyx-bearing afferents at different stages of postnatal development. We used whole cell patch clamp recordings in thin slices of gerbil crista neuroepithelium to investigate Na+ channels and firing patterns in central zone (CZ) and peripheral zone (PZ) afferents. PZ afferents are exclusively dimorphic, innervating type I and type II hair cells, whereas CZ afferents can form dimorphs or calyx-only terminals which innervate type I hair cells alone. All afferents expressed tetrodotoxin (TTX)-sensitive Na+ currents, but TTX-sensitivity varied with age. During the fourth postnatal week, 200–300 nM TTX completely blocked sodium currents in PZ and CZ calyces. By contrast, in immature calyces [postnatal day (P) 5–11], a small component of peak sodium current remained in 200 nM TTX. Application of 1 μM TTX, or Jingzhaotoxin-III plus 200 nM TTX, abolished sodium current in immature calyces, suggesting the transient expression of voltage-gated sodium channel 1.5 (Nav1.5) during development. A similar TTX-insensitive current was found in early postnatal crista hair cells (P5–9) and constituted approximately one third of the total sodium current. The Nav1.6 channel blocker, 4,9-anhydrotetrodotoxin, reduced a component of sodium current in immature and mature calyces. At 100 nM 4,9-anhydrotetrodotoxin, peak sodium current was reduced on average by 20% in P5–14 calyces, by 37% in mature dimorphic PZ calyces, but by less than 15% in mature CZ calyx-only terminals. In mature PZ calyces, action potentials became shorter and broader in the presence of 4,9-anhydrotetrodotoxin implicating a role for Nav1.6 channels in firing in dimorphic afferents. [ABSTRACT FROM AUTHOR]

Copyright of Arquivo Brasileiro de Medicina Veterinaria e Zootecnia is the property of Universidade Federal de Minas Gerais, Escola de Veterinaria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Este artigo tem por objetivo analisar certos enunciados religiosos para o cotidiano da infância masculina presentes no manual pedagógico Escola Nova, Christã, e Politica, Na qual se ensinão os primeiros rudimentos, que deve saber o Menino Christão, e se lhes dão regras para com facilidade, e em pouco tempo aprender a ler, escrever e contar. Publicada em Portugal inicialmente no ano de 1756 a obra de autoria de Francisco Luiz Ameno (1713-1793) foi registrada pelo pseudônimo de D. Leonor Thomasia de Sousa e Silva. Ao enquadrar o manual na categoria de Literatura de Comportamento Social, interessa-me, em particular, verificar as instruções que o autor prescreveu para a rotina de um menino cristão no contexto setecentista português. Nesse sentido, o conjunto das práticas recomendadas foram percebidas, aqui como mecanismos para a produção de máximas morais e de comportamentos socialmente desejáveis, que constituíram modos específicos de ser menino infantil em Portugal no século XVIII.

Em galos de matriz pesada, o peso dos testículos se associa positivamente com a produção diária de espermatozoides e com a fertilidade. Contudo, os testículos de aves se localizam na cavidade abdominal, não sendo acessíveis para exame andrológico como os testículos de mamíferos. A avaliação reprodutiva de galos de matriz pesada é subjetiva e se baseia em características como peso corporal (PC), qualidade de pés e pernas e morfologia de cloaca e crista. Estudos que validem o potencial de associação dessas características fenotípicas com parâmetros da morfometria testicular são raros, principalmente quando se consideram galos de matriz pesada manejados em lotes comerciais. Escores de cloaca e de crista e parâmetros da morfometria testicular foram avaliados em galos Cobb 500 Slow adultos das categorias de PC leve (

In the vestibular periphery neurotransmission between hair cells and primary afferent nerves occurs via specialized ribbon synapses. Type I vestibular hair cells (HCIs) make synaptic contacts with calyx terminals, which enclose most of the HCI basolateral surface. To probe synaptic transmission, whole cell patchclamp recordings were made from calyx afferent terminals isolated together with their mature HCIs from gerbil crista. Neurotransmitter release was measured as excitatory postsynaptic currents (EPSCs) in voltage clamp. Spontaneous EPSCs were classified as simple or complex. Simple events exhibited a rapid rise time and a fast mono-exponential decay (time constant ＜ 1 ms). The remaining events, constituting ~40% of EPSCs, showed more complex characteristics. Extracellular Sr²⁺ greatly increased EPSC frequency, and EPSCs were blocked by the AMPA receptor blocker NBQX. The role of presynaptic Ca²⁺ channels was assessed by application of the L-type Ca²⁺ channel blocker nifedipine (20 µM), which reduced EPSC frequency. In contrast, the L-type Ca²⁺ channel opener BAY K 8644 increased EPSC frequency. Cyclothiazide increased the decay time constant of averaged simple EPSCs by approximately twofold. The low-affinity AMPA receptor antagonist γ-D-glutamylglycine (2 mM) reduced the proportion of simple EPSCs relative to complex events, indicating glutamate accumulation in the restricted cleft between HCI and calyx. In crista slices EPSC frequency was greater in central compared with peripheral calyces, which may be due to greater numbers of presynaptic ribbons in central hair cells. Our data support a role for L-type Ca²⁺ channels in spontaneous release and demonstrate regional variations in AMPA-mediated quantal transmission at the calyx synapse. NEW & NOTEWORTHY In vestibular calyx terminals of mature cristae we find that the majority of excitatory postsynaptic currents (EPSCs) are rapid monophasic events mediated by AMPA receptors. Spontaneous EPSCs are reduced by an L-type Ca²⁺ channel blocker and notably enhanced in extracellular Sr²⁺. EPSC frequency is greater in central areas of the crista compared with peripheral areas and may be associated with more numerous presynaptic ribbons in central hair cells. [ABSTRACT FROM AUTHOR]

Objectives/hypothesis: In this study, our objective was to histopathologically analyze the peripheral vestibular system in patients with Mondini dysplasia.Study Design: Comparative human temporal bone study.Methods: We assessed the sensory epithelium of the human vestibular system with a focus on the number of type I and type II hair cells, as well as the total number of hair cells. We compared those numbers in our Mondini dysplasia group versus our control group.Results: The loss of type I and type II hair cells in the cristae of the superior, lateral, and posterior semicircular canals, as well as in the saccular and utricular macula, was significantly higher in our Mondini dysplasia group than in our control group. The total number of hair cells significantly decreased in the cristae of the superior, lateral, and posterior semicircular canals, as well as in the saccular and utricular macula, in our Mondini dysplasia group.Conclusion: Loss of vestibular hair cells can lead to vestibular dysfunction in patients with Mondini dysplasia.Level Of Evidence: NA Laryngoscope, 127:206-209, 2017. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the genetic causes of vestibular dysfunction. We used vestibular sensory-evoked potentials (VsEPs) to characterize the vestibular function of 35 inbred mouse strains selected from the Hybrid Mouse Diversity Panel and demonstrated strain-dependent phenotypic variation in vestibular function. Using these phenotypic data, we performed the first genome-wide association study controlling for population structure that has revealed two highly suggestive loci, one of which lies within a haplotype block containing five genes (Stard6, 4930503L19Rik, Poli, Mbd2, Dcc) on Chr. 18 (peak SNP rs29632020), one gene, deleted in colorectal carcinoma (Dcc) has a well-established role in nervous system development. An in-depth analysis of Dcc-deficient mice demonstrated elevation in mean VsEP threshold for Dcc (+/-) mice (-11.86 dB) compared to wild-type (-9.68 dB) littermates. Synaptic ribbon studies revealed Dcc (-/-) (P0) and Dcc (+/-) (6-week-old) mice showed lower density of the presynaptic marker (CtBP2) as compared to wild-type controls. Vestibular ganglion cell counts of Dcc (-/-) (P0) was lower than controls. Whole-mount preparations showed abnormal innervation of the utricle, saccule, and crista ampullaris at E14.5, E16.5, and E18.5. Postnatal studies were limited by the perinatal lethality in Dcc (-/-) mice. Expression analyses using in situ hybridization and immunohistochemistry showed Dcc expression in the mouse vestibular ganglion (E15.5), and utricle and crista ampullaris (6-week-old), respectively. In summary, we report the first GWAS for vestibular functional variation in inbred mice and provide evidence for the role of Dcc in the normal innervation of the peripheral vestibular system. [ABSTRACT FROM AUTHOR]

O experimento foi conduzido com o objetivo de avaliar qual o melhor nível energético na dieta para galos reprodutores de corte da linhagem Cobb 500 e a influência da presença da crista em parâmetros como: peso corporal, volume de sêmen, concentração de células espermáticas e fertilidade. Foram utilizados 32 galos de 22 até 44 semanas de idade, distribuídos aleatoriamente em gaiolas metálicas com comedouro e bebedouro tipo calha. Utilizou-se um delineamento experimental inteiramente casualizado, em esquema fatorial 2x2, sendo dois níveis de energia (2600 e 2800kcal EM kg-1) e duas condições de crista (com e sem corte), formando quatro tratamentos com oito repetições, com uma ave por unidade experimental. Na 24ª semana, iniciou-se a coleta de dados para a análise estatística, sempre intercalando a semana de pesagem das aves com a coleta de sêmen, o qual foi coletado através do método Americano e, para contagem de células espermáticas, fez-se a diluição do sêmen a base de formol salina tamponada para posterior leitura na câmara de Neubauer. Avaliou-se a fertilidade dos machos inseminando artificialmente seis fêmeas por tratamento, duas vezes por semana com 0,05mL de sêmen por fêmea. Os ovos foram coletados quatro vezes por dia, identificados, desinfetados e incubados em condições similares. No 21° dia de incubação, os ovos que não eclodiram foram quebrados e examinados macroscopicamente para calcular a fertilidade. Os níveis de energia estudados não revelaram diferença significativa no peso corporal e no volume de sêmen dos galos durante o período experimental. Já o corte da crista reduziu 9,5% do peso corporal e 24% da fertilidade em relação a aves com crista inteira. Nas semanas 29ª, 35ª, 37ª, e 43ª, observou-se maior concentração de células espermáticas em aves que receberam dieta com 2600kcal EM kg-1. Conclui-se que o nível de 2600kcal EM kg-1 é suficiente para atender os parâmetros reprodutivos dos galos e a presença da crista é fundamental para manter a alta fertilidade em aves de 42 e 43 semanas de idade.The experiment was carried out to evaluate which is the best the diet energy level diet for male broiler breeders of cutting Cobb 500 and the influence of the presence of the crest on parameters such as body weight, semen volume, sperm cell concentration and fertility. Were used 32 roosters for 22 to 44 weeks of age, they were randomly assigned to cages equipped with feeders and drinkers type gutter. The experimental design was entirely casualized in a factorial scheme 2x2 two comb conditions (with and without crest) and two levels of metabolizable energy (2600 and 2800kcal kg-1). There was four treatments with eight replications, with one bird per experimental unit. At week 24th began collecting data for statistical analysis, when merging the week weighing the birds to the collection of semen, which was collected through the American method and count of sperm cells, The dilution of semen-based formaldehyde buffered saline and then reading in a Neubauer chamber. We assessed male fertility through artificial insemination of six females per treatment, twice weekly with 0.05mL of semen per female. Eggs were collected four times a day, identified, disinfected and incubated in the same conditions. After 21 of incubation, eggs not hatched were broken and macroscopically examined to calculate the fertility. The energy levels studied revealed no significant difference in body weight and volume of semen of roosters during the experimental period. Since cutting the crest reduced body weight and fertility of 9.5% and 24% respectively in relation to birds crested whole. In the weeks 29th, 35th, 37th and 43th there was a higher concentration of sperm cells in birds fed the diet with 2600kcal kg-1. It is concluded that the level of 2600kcal kg-1 is sufficient to meet the reproductive parameters of roosters and the presence of the crest is needed to maintaining high fertility in 42 and 43 weeks of age birds.

O objetivo deste experimento foi avaliar o efeito de diferentes níveis de proteína bruta (PB) na dieta para machos com ou sem crista. Peso corporal, volume de sêmen, número de células espermáticas e fertilidade foram os parâmetros avaliados. Foram utilizados 32 machos Cobb 500, 50% com crista inteira e 50% sem crista. Todos os machos foram submetidos às mesmas condições de manejo. Eles foram alojados em gaiolas metálicas individuais, com comedouro e bebedouro. O delineamento experimental usado foi o inteiramente casualizado com esquema fatorial 2x2, com duas condições de crista (com e sem) e dois níveis de proteína bruta (12 e 16%). O sêmen foi coletado por meio do método americano e o número de células espermáticas foi determinado por meio da câmara de Neubauer. Na 42ª, 43ª e 44ª semanas de idade, seis fêmeas para cada tratamento foram inseminadas artificialmente. As inseminações foram realizadas duas vezes por semana com sêmen fresco na dose de 0,05ml. Os ovos foram coletados quatro vezes por dia, identificados, desinfetados e incubados nas mesmas condições. Depois de 21 dias de incubação, os ovos foram quebrados e examinados macroscopicamente para análise da fertilidade. O nível de 12% de proteína bruta foi suficiente para atender as exigências reprodutivas, e a permanência da crista influenciou apenas o peso corporal dos machos, em que machos com crista apresentaram maior peso corporal.The objective of this trial was evaluated the effect of different crude protein (CP) levels of diet for males with or without coumbing. Body weight, semen volume, number of spermatic cells and fertility were evaluated. A total of 32 males Cobb 500 were used being 50% coumbed and 50% decoumbed males. The roosters were exposed the same management conditions in starting and rearing phases. They were housed in individual metallic cages with feeders and drinkers. The experimental design was entirely casualized in a factorial 2x2, two comb conditions (with or without) and two levels of crude protein (12 and 16%). Semen was collected using the American methods and number of spermatic cells was determined by counting in Neubauer chamber. At 42, 43 and 44 weeks of age, six females were artificially inseminated by treatment, twice a week, with dosage of 0.05ml of fresh semen. The eggs were collected four times a day, identified, disinfected and incubated in similar conditions. After 21 day of incubation they were broken and examined macroscopically to analyze the fertility. The level of 12% of crude protein was enough to assist the reproductive demands and the permanence of males. Combed males had body weight higher than without combed males.

Potassium-selective ion channels are important for accurate transmission of signals from auditory and vestibular sensory end organs to their targets in the central nervous system. During different gravity conditions, astronauts experience altered input signals from the peripheral vestibular system resulting in sensorimotor dysfunction. Adaptation to altered sensory input occurs, but it is not explicitly known whether this involves synaptic modifications within the vestibular epithelia. Future investigations of such potential plasticity require a better understanding of the electrophysiological mechanisms underlying the known heterogeneity of afferent discharge under normal conditions. This study advances this understanding by examining the role of the Kv1 potassium channel family in mediating action potentials in specialized vestibular afferent calyx endings in the gerbil crista and utricle. Pharmacological agents selective for different sub-types of Kv1 channels were tested on membrane responses in whole cell recordings in the crista. Kv1 channels sensitive to α-dendrotoxin and dendrotoxin-K were found to prevail in the central regions, whereas K+ channels sensitive to margatoxin, which blocks Kv1.3 and 1.6 channels, were more prominent in peripheral regions. Margatoxin-sensitive currents showed voltage-dependent inactivation. Dendrotoxin-sensitive currents showed no inactivation and dampened excitability in calyces in central neuroepithelial regions. The differential distribution of Kv1 potassium channels in vestibular afferents supports their importance in accurately relaying gravitational and head movement signals through specialized lines to the central nervous system. Pharmacological modulation of specific groups of K+ channels could help alleviate vestibular dysfunction on earth and in space.

During development of vestibular hair cells, K + conductances are acquired in a specific pattern. Functionally mature vestibular hair cells express different complements of K + channels which uniquely shape the hair cell receptor potential and filtering properties. In amniote species, type I hair cells (HCI) have a large input conductance due to a ubiquitous low–voltage-activated K + current that activates with slow sigmoidal kinetics at voltages negative to the membrane resting potential. In contrast type II hair cells (HCII) from mammalian and non-mammalian species have voltage-dependent outward K + currents that activate rapidly at or above the resting membrane potential and show significant inactivation. A-type, delayed rectifier and calcium-activated K + channels contribute to the outward K + conductance and are present in varying proportions in HCII. In many species, K + currents in HCII in peripheral locations of vestibular epithelia inactivate more than HCII in more central locations. Two types of inward rectifier currents have been described in both HCI and HCII. A rapidly activating K + -selective inward rectifier current (I K1 , mediated by Kir2.1 channels) predominates in HCII in peripheral zones, whereas a slower mixed cation inward rectifier current (I h ), shows greater expression in HCII in central zones of vestibular epithelia. The implications for sensory coding of vestibular signals by different types of hair cells are discussed. This article is part of a Special Issue entitled . [ABSTRACT FROM AUTHOR]

A avulsão da cartilagem da crista ilíaca é uma lesão infreqüente e raramente é descrita na literatura. Atletas jovens e adolescentes são os indivíduos mais predispostos à lesão. O trauma indireto causado pela contração da musculatura aderida à crista ilíaca e o movimento de angulação do tronco em sentido oposto ao da contração é o mecanismo mais comum de arrancamento da cartilagem. Como na maioria dos casos não existe trauma direto, esses podem não ser diagnosticados se não considerarmos essa possibilidade de lesão. Relatamos dois casos atendidos em nosso Serviço, que apresentaram lesão na cartilagem devido a um trauma indireto (contração muscular abrupta). Ambos foram tratados de maneira incruenta, com excelente evolução.Avulsion of the iliac crest cartilage is an infrequent, rarely described lesion. Young and adolescent athletes are prone to this lesion. Indirect trauma caused by contraction of the muscles inserted at the iliac crest and the angulation move-ment of the trunk in direction opposite to the contraction is the most common mechanism causing cartilage tearing. As most of the cases do not present direct trauma, diagnosis can be missed if that possibility is not considered. Two cases attended by our Service are described. Lesion in the cartilage was observed due to an indirect trauma (abrupt muscular contraction). Both cases were treated and the evoluti-on was excellent.