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Abstract Objectives Evaluate the relationship between cardiovascular disease (CVD) risk factors and cochlear function in African Americans. Methods Relationships between hearing loss, cochlear function, and CVD risk factors were assessed in a cross‐sectional analysis of 1106 Jackson Heart Study participants. Hearing loss was defined as puretone average (PTA0.5,1,2,4) > 15 dB HL. Distortion product otoacoustic emissions (DPOAEs) were collected for f2 = 1.0–8.0 kHz. Two amplitude averages were computed: DPOAElow (f2 ≤ 4 kHz) and DPOAEhigh (f2 ≥ 6 kHz). Based on major CVD risk factors (diabetes, current smoking, total cholesterol ≥240 mg/dL or treatment, and systolic blood pressure [BP]/diastolic BP ≥ 140/≥90 mmHg or treatment), four risk groups were created: 0, 1, 2, and ≥3 risk factors. Logistic regression estimated the odds of hearing loss and absent/reduced DPOAElow and DPOAEhigh by CVD risk status adjusting for age, sex, education, BMI, vertigo, and noise exposure. Results With multivariable adjustment, diabetes was associated with hearing loss (OR = 1.48 [95% CI: 1.04–2.10]). However, there was not a statistically significant relationship between CVD risk factors (individually or for overall risk) and DPOAEs. Conclusion Diabetes was associated with hearing loss. Neither individual CVD risk factors nor overall risk showed a relationship to cochlear dysfunction. Level of Evidence 2b.

Blast overpressure has become an increasing cause of brain injuries in both military and civilian populations. Though blast's direct effects on the cochlea and vestibular organs are active areas of study, little attention has been given to the ear's contribution to the overall spectrum of blast injury. Acute autonomic responses to blast exposure, including bradycardia and hypotension, can cause hypoxia and contribute to blast-induced neurotrauma. Existing literature suggests that these autonomic responses are elicited through blast impacting the thorax and lungs. We hypothesize that the unprotected ear also provides a vulnerable locus for blast to cause autonomic responses. We designed a blast generator that delivers controlled overpressure waves into the ear canal without impacting surrounding tissues in order to study the ear's specific contribution to blast injury. Anesthetized adult rats' left ears were exposed to a single blast wave ranging from 0 to 110 PSI (0–758 kPa). Blast exposed rats exhibited decreased heart rates and blood pressures with increased blast intensity, similar to results gathered using shock tubes and whole-body exposure in the literature. While rats exposed to blasts below 50 PSI (345 kPa) exhibited increased respiratory rate with increased blast intensity, some rats exposed to blasts higher than 50 PSI (345 kPa) stopped breathing immediately and ultimately died. These autonomic responses were significantly reduced in vagally denervated rats, again similar to whole-body exposure literature. These results support the hypothesis that the unprotected ear contributes to the autonomic responses to blast. Keywords: Blast waves, Autonomic responses, Ear, Neurotrauma

Recent projections suggest that food security may face threats due to climate change and population growth. Global warming is altering ocean temperatures, impacting productivity and aquatic ecosystems. This review delves into the impact of heat stress on fish aquaculture, focusing on the neuroendocrine system, controlled by the hypothalamic-pituitary-interrenal (HPI) axis. This axis regulates stress responses via cortisol and catecholamines, influencing energy metabolism and stress adaptation. The review discusses molecular adaptations in skeletal muscle and liver, affecting gene expression related to growth and energy metabolism. On the other hand, heat stress provokes notable molecular responses, altering the expression of genes involved in glycolysis and oxidative phosphorylation, and hormonal pathways like growth hormone and insulin growth factors, which are vital for metabolic regulation and muscle growth. In summary, this review provides insights into the neuroendocrine and molecular mechanisms underlying fish responses to thermal stress, emphasizing the importance of skeletal muscle and liver tissues in mediating physiological adaptations. Furthermore, it analyzes the implications for protein synthesis, cellular signaling pathways, oxidative stress, and enzymatic responses in aquatic organisms, highlighting the importance of understanding these molecular adaptations to develop effective mitigation strategies that ensure the sustainability of aquaculture systems amidst changing conditions.

From the early Miocene, the uplift of the Andes Mountains, intense volcanic activity and the occurrence of successive periods of dryness and humidity would have differentially influenced the modification of Altiplano watersheds, and consequently the evolutionary history of the taxa that live there. We analyzed Orestias populations from the Caquena and Lauca Altiplanic sub-basins of northern Chile to determine their genetic differentiation and relationship to their geographical distribution using mitochondrial (D-loop) and nuclear (microsatellite) molecular markers and to reconstruct its biogeographic history on these sub-basins. The results allowed reconstructing and reevaluating the evolutionary history of the genus in the area; genic diversity and differentiation together with different founding genetic groups suggest that Orestias have been spread homogeneously in the study area and would have experienced local disturbances that promoted isolation and diversification in restricted zones of their distribution.

It is known that selenium (Se) is an essential trace element, important for the growth and other biological functions of fish. One of its most important functions is to contribute to the preservation of certain biological components, such as DNA, proteins, and lipids, providing protection against free radicals resulting from normal metabolism. The objective of this study was to evaluate and optimize selenium accumulation in the native yeast Rhodotorula mucilaginosa 6S. Sodium selenite was evaluated at different concentrations (5–10–15–20–30–40 mg/L). Similarly, the effects of different concentrations of nitrogen sources and pH on cell growth and selenium accumulation in the yeast were analyzed. Subsequently, the best cultivation conditions were scaled up to a 2 L reactor with constant aeration, and the proteome of the yeast cultured with and without sodium selenite was evaluated. The optimal conditions for biomass generation and selenium accumulation were found with ammonium chloride and pH 5.5. Incorporating sodium selenite (30 mg/L) during the exponential phase in the bioreactor after 72 h of cultivation resulted in 10 g/L of biomass, with 0.25 mg total Se/g biomass, composed of 25% proteins, 15% lipids, and 0.850 mg total carotenoids/g biomass. The analysis of the proteomes associated with yeast cultivation with and without selenium revealed a total of 1871 proteins. The results obtained showed that the dynamic changes in the proteome, in response to selenium in the experimental medium, are directly related to catalytic activity and oxidoreductase activity in the yeast. R. mucilaginosa 6S could be an alternative for the generation of selenium-rich biomass with a composition of other nutritional compounds also of interest in aquaculture, such as proteins, lipids, and pigments.

La Sociedad Mexicana de Historia de la Educación ha demostrado un encomiable compromiso con la generación de conocimiento sobre la historia de la educación desde su creación. De particular relevancia resulta mencionar este compromiso en las circunstancias actuales, ya que a pesar de la pandemia por el virus de la COVID-19 y los enormes retos y lamentables pérdidas humanas derivadas de ella, los miembros de la SOMEHIDE han continuado su labor. Así, en noviembre del 2020 llevaron a cabo el XVI Encuentro Internacional de Historia de la Educación “Migraciones, fronteras y reformas educativas” y han logrado mantener sus esfuerzos editoriales publicando el Anuario Mexicano de Historia de la Educación, la colección bibliográfica “Historia de la educación en México” y esta Revista Mexicana de Historia de la Educación de publicación semestral financiada con las cuotas de los miembros de la Sociedad. Aunado a lo anterior la SOMEHIDE ha dado continuidad a los procesos internos de renovación de su mesa directiva y con ello se consolida como la Sociedad representativa de las y los historiadores de la educación de México, una de las más importantes en nuestro continente tanto por su productividad, como por la calidad del trabajo de su membresía.

Vestibular evoked myogenic potentials (VEMP) have been used to assess otolith function in clinics worldwide. However, there are accumulating evidence suggesting that the clinically used sound stimuli activate not only the otolith afferents, but also the canal afferents, indicating canal contributions to the VEMPs. To better understand the neural mechanisms underlying the VEMPs and develop discriminative VEMP protocols, we further examined sound-evoked responses of the vestibular nucleus neurons and the abducens neurons, which have the interneurons and motoneurons of the vestibulo-ocular reflex (VOR) pathways. Air-conducted clicks (50-80 dB SL re ABR threshold, 0.1 ms duration) or tone bursts (60-80 dB SL, 125-4,000 Hz, 8 ms plateau, 1 ms rise/fall) were delivered to the ears of Sprague-Dawley or Long-Evans rats. Among 425 vestibular nucleus neurons recorded in anesthetized rats and 18 abducens neurons recorded in awake rats, sound activated 35.9% of the vestibular neurons that increased discharge rates for ipsilateral head rotation (Type I neuron), 15.7% of the vestibular neurons that increased discharge rates for contralateral head rotation (Type II neuron), 57.2% of the vestibular neurons that did not change discharge rates during head rotation (non-canal neuron), and 38.9% of the abducens neurons. Sound sensitive vestibular nucleus neurons and abducens neurons exhibited characteristic tuning curves that reflected convergence of canal and otolith inputs in the VOR pathways. Tone bursts also evoked well-defined eye movements that increased with tone intensity and duration and exhibited peak frequency of ∼1,500 Hz. For the left eye, tone bursts evoked upward/rightward eye movements for ipsilateral stimulation, and downward/leftward eye movements for contralateral stimulation. These results demonstrate that sound stimulation results in activation of the canal and otolith VOR pathways that can be measured by eye tracking devices to develop discriminative tests of vestibular function in animal models and in humans., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Chen, Huang, Yu, Tang, Zhang, Xu, Arteaga, Allison, Mustain, Donald, Rappai, Zhang, Zhou and Zhu.)