Noise-Induced Hearing Threshold Shift Correlated with Body Weight and External-Ear Amplification in Chinchilla: a Preliminary Analysis.

BACKGROUND: External-ear amplification (EEA) has been shown to vary from 5-19 dB-A in large datasets of pediatric, adolescent, and adult human participants. However, variable EEA is an overlooked characteristic that likely plays a role in individual noise-induced hearing loss (NIHL) susceptibility. A noise exposure varying 5-19 dB-A translates to high-EEA individuals theoretically experiencing 3-4 times greater NIHL risk than low-EEA individuals. OBJECTIVE: The purpose of this preliminary analysis was to test the hypothesis that higher EEA is correlated with increased noise-induced threshold shift susceptibility. DESIGN: Nine chinchillas were exposed to 4-kHz octave-band noise at 89 dB-SPL for 24 h. Auditory brainstem response thresholds were obtained pre-exposure, 24-h post-exposure, and 4-week post-exposure. Relationships between EEA and threshold shift were analyzed. RESULTS: Open-ear EEA ranged 11-19 dB-SPL, and occluded-ear EEA ranged 10-21 dB-SPL. Higher occluded-ear EEA was correlated with increased NIHL susceptibility (p = 0.04), as was lower body weight (p = 0.01). Male animals exhibited more threshold shift than female animals (p = 0.02), lower body weight than female animals (p = 0.02), and higher occluded-ear EEA (male mean = 18 dB; female mean = 15 dB). CONCLUSIONS: Taken together, increased threshold shift susceptibility was observed in the smallest animals, animals with the highest occluded-ear EEA, and in male animals (which tended to have higher occluded-ear EEA). Given the established relationship between smaller body size and higher occluded-ear EEA, these preliminary results suggest that body size (and occluded-ear EEA; a function of body size) could be a potential, underlying driver of NIHL susceptibility differences, rather than true sex differences.

Young Children's Development and Behavior: Associations with Timing of Household Food Insecurity in a Racially and Ethnically Diverse Early Head Start Sample.

OBJECTIVE: The objective of this study was to assess the impact of household food insecurity (HFI) over time on behavioral and developmental health in early childhood while considering the impact of timing/persistence of HFI and potential differences among racially or ethnically minoritized children. METHODS: Families from the Early Head Start Family and Child Experiences Study (N = 760) were followed longitudinally until age 3 years. Caregiver interview data were collected on HFI, problem behaviors (PBs), delays in development (DD), and sociodemographic information. Analysis of Covariances examined differences between persistent vs transient HFI. Multiple regressions examined the impact of HFI on PB and DD and whether this relation was stronger in racially or ethnically minoritized children. RESULTS: The timing of HFI differentially affected PB, such that those with persistent HFI demonstrated greater PB than those with only early or only late HFI. A different pattern was identified for DD, in which those with late HFI had more DD than those with persistent HFI. Over and above other sociodemographics, including maternal risk factors and an income-to-needs ratio, HFI was associated with greater PB for children of all races and ethnicities. HFI was associated with more DD in non-Latino/a/e/x White families compared with non-Latino/a/e/x Black and Latino/a/e/x families. CONCLUSION: Meaningful differences were found in how the persistence/timing of HFI is differentially associated with PB and DD. In addition, while controlling for socioeconomic risk, a cumulative risk effect was not observed in how HFI affected racially or ethnically minoritized children.

Green Approach toward Triazole forming Reactions for Developing Anticancer Drugs.

Compounds containing triazole have many significant applications in the dye and ink industry, corrosion inhibitors, polymers, and pharmaceutical industries. These compounds possess many antimicrobial, antioxidant, anticancer, antiviral, anti-HIV, antitubercular, and anticancer activities. Several synthetic methods have been reported for reducing time, minimizing synthetic steps, and utilizing less hazardous and toxic solvents and reagents to improve the yield of triazoles and their analogues synthesis. Among the improvement in methods, green approaches towards triazole forming biologically active compounds, especially anticancer compounds, would be very important for pharmaceutical industries as well as global research community. In this article, we have reviewed the last five years of green chemistry approaches on click reaction between alkyl azide and alkynes to install 1,2,3-triazole moiety in natural products and synthetic drug-like molecules, such as in colchicine, flavanone cardanol, bisphosphonates, thiabendazoles, piperazine, prostanoid, flavonoid, quinoxalines, C-azanucleoside, dibenzylamine, and aryl-azotriazole. The cytotoxicity of triazole hybrid analogues was evaluated against a panel of cancer cell lines, including multidrug-resistant cell lines.

The middle ear muscle reflex: Current and future role in assessing noise-induced cochlear damage.

The middle ear muscle reflex (MEMR) in humans is a bilateral contraction of the middle ear stapedial muscle in response to moderate-to-high intensity acoustic stimuli. Clinically, MEMR thresholds have been used for differential diagnosis of otopathologies for decades. More recently, changes in MEMR amplitude or threshold have been proposed as an assessment for noise-induced synaptopathy, a subclinical form of cochlear damage characterized by suprathreshold hearing problems that occur as a function of inner hair cell (IHC) synaptic loss, including hearing-in-noise deficits, tinnitus, and hyperacusis. In animal models, changes in wideband MEMR immittance have been correlated with noise-induced synaptopathy; however, studies in humans have shown more varied results. The discrepancies observed across studies could reflect the heterogeneity of synaptopathy in humans more than the effects of parametric differences or relative sensitivity of the measurement. Whereas the etiology and degree of synaptopathy can be carefully controlled in animal models, synaptopathy in humans likely stems from multiple etiologies and thus can vary greatly across the population. Here, we explore the evolving research evidence of the MEMR response in relation to subclinical noise-induced cochlear damage and the MEMR as an early correlate of suprathreshold deficits.

No Reduction in the 226-Hz Probe Tone Acoustic Reflex Amplitude Following Severe Inner Hair Cell Loss in Chinchillas.

The relationship between the middle ear acoustic reflex (AR) and inner hair cell (IHC) loss is currently unknown. Given that IHC are believed to convey nearly all acoustic information to the central auditory nervous system, it has been assumed that loss of IHC would significantly impact the AR. To evaluate this relationship, we assessed the presence and amplitude of the AR in chinchillas before and after treatment with carboplatin, an anticancer drug that reliably and selectively destroys IHC in this species. Baseline measures of hearing sensitivity, including auditory brainstem response (ABR) thresholds and distortion product otoacoustic emissions (DPOAE), were assessed and then re-evaluated following carboplatin treatment. Post-carboplatin ABR thresholds and DPOAE were found to be unchanged or slightly elevated; results were consistent with published reports. Our main hypothesis was that loss of IHC would abolish the reflex or significantly reduce its amplitude. Contrary to our hypothesis, the ipsilateral 226-Hz AR continued to be reliably elicited following carboplatin treatment. Post-mortem histological analysis confirmed significant IHC loss (65-85 %), but no measurable loss of outer hair cells (OHCs). Given that loss of IHC alone does not significantly reduce the 226-Hz AR, our results suggest that few IHC are needed to maintain the 226-Hz AR response. These results suggest additional studies are needed to better understand the role of IHC in the reflex arc, present opportunities to further study the reflex pathway, and could change how we use the clinical AR as a potential diagnostic tool for IHC dysfunction, including those related to IHC synaptopathy.

Latinx dual language learners in the U.S.: Examining family context during early social emotional development.

Latinx dual language learners (DLLs) make up a large, growing population in the United States, yet little is known about their early childhood experiences, particularly regarding parenting, socioeconomic risk, and social emotional development (SED). This prospective, longitudinal study examined whether parental intrusiveness, parental stress, and parental warmth function differently in Latinx DLL families as compared to White monolingual (ML) families while controlling for relevant sociodemographic factors. Data were drawn from the Early Head Start (EHS) family and child experiences study, where White ML (n = 143) and Latinx DLL (n = 247) children and families were assessed at ages 2 and 3. Results indicated a significant interaction between Latinx DLL status and parental intrusiveness on behavior problems. Simple slopes indicated that greater intrusiveness was related to increased behavior problems for White ML families but was not related in Latinx DLL families. There was no significant interaction, however, between parental stress and Latinx DLL status on children's SED. Further, parental warmth did not further moderate the relationship between parental intrusiveness and Latinx DLL status. Overall, there were both similarities and differences between Latinx DLLs and White MLs in both the prevalence of these characteristics and how they relate to child behavior. These results highlight the importance of considering contextual factors, such as ethnic culture and language status, when examining parenting in both clinical and research settings. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Effect of Selective Carboplatin-Induced Inner Hair Cell Loss on Temporal Integration in Chinchillas.

Integration of acoustic information over time is essential for processing complex stimuli, such as speech, due to its continuous variability along the time domain. In both humans and animals, perception of acoustic stimuli is a function of both stimulus intensity and duration. For brief acoustic stimuli, as duration increases, thresholds decrease by approximately 3 dB for every doubling in duration until stimulus duration reaches 500 ms, a phenomenon known as temporal integration. Although hearing loss and damage to outer hair cells (OHC) have been shown to alter temporal integration in some studies, the role of cochlear inner hair cells (IHC) on temporal integration is unknown. Because IHC transmit nearly all acoustic information to the central auditory system and are believed to code both intensity and timing information, these sensory cells likely play a critical role in temporal integration. To test the hypothesis that selective IHC loss degrades the temporal integration function, behaviorally trained chinchillas were treated with carboplatin, a drug known to selectively destroy IHC with little to no effect on OHC in this species. Pure-tone thresholds were assessed across frequencies (1, 2, 4, 8, 12 kHz) as a function of signal duration (500, 100, 50, 10, and 5 ms). Baseline testing showed a significant effect of duration on thresholds. Threshold decreased as a function of increasing duration, as expected. Carboplatin treatment (75 mg/kg) produced a moderate to severe loss of IHC (45-85%) with little-to-no loss of OHC. Contrary to our hypothesis, post-carboplatin temporal integration thresholds showed no significant differences from baseline regardless of stimulus duration or frequency. These data suggest that few IHC are necessary for temporal integration of simple stimuli. Temporal integration may be sensitive to loss of OHC and loss of cochlear non-linearities but does not appear to be sensitive to selective IHC loss.

Current topics in hearing research: Deafferentation and threshold independent hearing loss.

Hearing research findings in recent years have begun to change how we think about hearing loss and how we consider the risk of auditory damage from noise exposure. These findings include evidence of noise-induced cochlear damage in the absence of corresponding permanent threshold elevation or evidence of hair cell loss. Animal studies in several species have shown that noise exposures that produce robust but only temporary threshold shifts can permanently damage inner hair cell synaptic ribbons. This type of synaptic degeneration has also been shown to occur as a result of aging in animals and humans. The emergence of these data has motivated a number of clinical studies aimed at identifying the perceptual correlates associated with synaptopathy. The deficits believed to arise from synaptopathy include poorer hearing in background noise, tinnitus and hyperacusis (loudness intolerance). However, the findings from human studies have been mixed. Key questions remain as to whether synaptopathy reliably produces suprathreshold perceptual deficits or whether it serves as an early indicator of auditory damage with suprathreshold deficits emerging later as a function of further cochlear damage. Here, we provide an overview of both human and animal studies that explore the relationship among inner hair cell damage, including loss of afferent synapses, auditory thresholds, and suprathreshold measures of hearing.

Cochlear Preconditioning as a Modulator of Susceptibility to Hearing Loss.

Significance: Acquired sensorineural hearing loss is a major public health problem worldwide. The leading causes of sensorineural hearing loss are noise, aging, and ototoxic medications, with the key underlying pathology being damage to the cochlea. The review focuses on the phenomenon of preconditioning, in which the susceptibility to cochlear injury is reduced by exposing the ear to a stressful stimulus. Recent Advances: Cochlear conditioning has focused on the use of mono-modal conditioning, specifically conditioning the cochlea with moderate noise exposures before a traumatic exposure that causes permanent hearing loss. Recently, cross-modal conditioning has been explored more thoroughly, to prevent not only noise-induced hearing loss, but also age-related and drug-induced hearing losses. Critical Issues: Noise exposures that cause only temporary threshold shifts (TTSs) can cause long-term synaptopathy, injury to the synapses between the inner hair cells and spiral ganglion cells. This discovery has the potential to significantly alter the field of cochlear preconditioning with noise. Further, cochlear preconditioning can be the gateway to the development of clinically deployable therapeutics. Therefore, understanding the underlying mechanisms of conditioning is crucial for optimizing clinical protection against sensorineural hearing loss. Future Directions: Before the discovery of synaptopathy, noise exposures that caused only TTSs were believed to be either harmless or potentially beneficial. Any considerations of preconditioning with noise must consider the potential for injury to the synapses. Further, the discovery of different methods to precondition the cochlea against injury will yield new avenues for protection against hearing loss in the vulnerable populations. Antioxid. Redox Signal. 36, 1215-1228.

Contextualizing the role of intrusive parenting in toddler behavior problems and emotion regulation: Is more always worse?

Intrusive parenting has been traditionally considered a negative parenting style and includes actions that are overly directive and controlling of children's behavior. However, current research aims to contextualize this parenting behavior. This study examined the relation between intrusive parenting and early childhood behavior problems or emotion regulation, as well as the moderating role of race/ethnicity and developmental delay. Participants (n = 511; 47.4% male) were part of a larger, longitudinal Early Head Start study, entitled Baby FACES, with a racially and ethnically diverse sample (40.1% White, 18.7% Black, and 41.2% Hispanic). Behavior problems and developmental delay were assessed via parent report, while parent intrusiveness and emotion regulation were rated by observers. More use of intrusive parenting at age 2 was associated with greater behavior problems and less emotion regulation at age 3. However, this relation was moderated by race/ethnicity and developmental level. Greater intrusiveness was related to increased behavior problems and poorer emotion regulation for White and Hispanic/Latino families; they were unrelated in Black families. Similarly, although intrusive parenting and behavior problems were positively associated at all developmental levels, the relation was strongest for children with typical development. Further, fewer maternal risk factors, being female, and being Hispanic/Latino were associated with higher emotion regulation, and more risk factors were associated with more behavior problems. These findings highlight the importance of considering how a child's context and development interact with parenting style. Children may benefit from clinical assessment and intervention that considers this intersectionality. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

The rat animal model for noise-induced hearing loss.

Rats make excellent models for the study of medical, biological, genetic, and behavioral phenomena given their adaptability, robustness, survivability, and intelligence. The rat's general anatomy and physiology of the auditory system is similar to that observed in humans, and this has led to their use for investigating the effect of noise overexposure on the mammalian auditory system. The current paper provides a review of the rat model for studying noise-induced hearing loss and highlights advancements that have been made using the rat, particularly as these pertain to noise dose and the hazardous effects of different experimental noise types. In addition to the traditional loss of auditory function following acoustic trauma, recent findings have indicated the rat as a useful model in observing alterations in neuronal processing within the central nervous system following noise injury. Furthermore, the rat provides a second animal model when investigating noise-induced cochlear synaptopathy, as studies examining this in the rat model resemble the general patterns observed in mice. Together, these findings demonstrate the relevance of this animal model for furthering the authors' understanding of the effects of noise on structural, anatomical, physiological, and perceptual aspects of hearing.

The chinchilla animal model for hearing science and noise-induced hearing loss.

The chinchilla animal model for noise-induced hearing loss has an extensive history spanning more than 50 years. Many behavioral, anatomical, and physiological characteristics of the chinchilla make it a valuable animal model for hearing science. These include similarities with human hearing frequency and intensity sensitivity, the ability to be trained behaviorally with acoustic stimuli relevant to human hearing, a docile nature that allows many physiological measures to be made in an awake state, physiological robustness that allows for data to be collected from all levels of the auditory system, and the ability to model various types of conductive and sensorineural hearing losses that mimic pathologies observed in humans. Given these attributes, chinchillas have been used repeatedly to study anatomical, physiological, and behavioral effects of continuous and impulse noise exposures that produce either temporary or permanent threshold shifts. Based on the mechanistic insights from noise-exposure studies, chinchillas have also been used in pre-clinical drug studies for the prevention and rescue of noise-induced hearing loss. This review paper highlights the role of the chinchilla model in hearing science, its important contributions, and its advantages and limitations.

Manejo de la salud oral en el paciente pediátrico infectado por VIH / Oral health management in the HIV-infected pediatric patient

El síndrome de inmunodeficiencia adquirida (SIDA) se caracteriza por una infección adquirida ocasionada por el virus de la inmunodeficiencia humana (VIH), que afecta a la población linfocitaria CD4+ y que predispone al paciente a un estado de inmunodefi ciencia que lo hace susceptible a infecciones oportunistas severas y/o neoplasias inusuales. La infección por el VIH es un problema grave de salud pública, ya que hay alrededor de 34 millones de personas infectadas según el Centro Nacional de Prevención de Enfermedades de Atlanta; de esta población seropositiva para VIH 68 por ciento vive en África Subsahariana. El VIH se transmite a través de la contaminación con sangre, semen, fluidos vaginales y leche materna. Muchos de los portadores de este virus son asintomáticos lo que complica la situación en virtud de que si no se toman las precauciones de bioseguridad adecuadas, esta situación representa un riesgo para el profesional de la salud oral. Los odontólogos deben brindar un tratamiento adecuado a este tipo de pacientes e identifi car oportunamente cualquier riesgo de infección y complicaciones asociadas

cquired immunodeficiency syndrome (AIDS) is characterized by a seemingly irreversible impairment acquired in CD4 + lymphocyte population that predisposes the host to severe opportunistic infections and/or neoplastic unusual. Infection produced by human immunode-fi ciency virus (HIV) is a serious public health problem, as there are about 34 million people infected reported by the National Center for Disease Prevention Atlanta, this 68% HIV-positive population lives in Sub-Saharan Africa. HIV is transmitted through blood contamination, semen, vaginal fl uids and breast milk. Many patients infected with this virus are asymptomatic complicating the situation under if appropriate biosecurity measures are not taken; this situation represents a risk for oral health professional. Dentists should provide adequate treatment to these patients and promptly identify any risk of infection and as-sociated complications.

The Development of a Minority Recruitment Plan for Cancer Clinical Trials.

BACKGROUND: Cancer does not occur in all ethnic and racial groups at similar rates. In addition, responses to treatment also vary in certain ethnic and racial groups. For Hispanics, the overall cancer incidence is generally lower yet for some specific tumor types, the incidence rates are higher compared to other populations. OBJECTIVES: Although disparities are recognized for treatment outcomes and prevention methodologies for Hispanics and other minority populations, specific recruiting and reporting of minorities remains a challenge. In order to circumvent this problem, the Cancer Therapy and Research Center (CTRC) has developed a new minority recruitment plan for all cancer related clinical trials at this Institute. The overall goal of this initiative is to increase the accrual of minorities in cancer clinical trials by implementing several key interventions. METHOD: The Cancer Therapy & Research Center (CTRC) at the University of Texas Health Science Center at San Antonio established the Clinical Trials Accrual Task Force to develop and monitor interventions designed to increase accrual to cancer clinical trials, specifically the accrual of minorities with a focus on the Hispanic population that makes up 68% of the CTRC's catchment area. RESULTS: A Minority Accrual Plan (MAP) was implemented in March 2013 as part of the process for initiating and conducting cancer-related clinical trials at the CTRC. The Minority Accrual Plan focuses on Hispanic enrollment due to the characteristics of the South Texas population served by the CTRC but could be easily adapted to other populations. CONCLUSIONS: The CTRC has designed a process to prospectively address the challenge of deliberately enrolling minority subjects and accurately accounting for the results by implementing a Minority Accrual Plan for every cancer-related clinical trial at CTRC.