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Background: The Nijmegen Cochlear Implant Questionnaire (NCIQ) is a disease-specific questionnaire to determine the health-related quality of life (HRQoL) of patients before and after cochlear implantation., Objective: This study aimed to assess the validity and reliability of the German translation of the NCIQ., Materials and Methods: A prospective study was performed in 100 postlingually deaf or severely hearing-impaired patients. HRQoL was assessed using the NCIQ, the Abbreviated Profile of Hearing Aid Benefit (APHAB), and the Hearing Participation Scale (HPS) before as well as 3 and 6 months after cochlear implantation. An untreated group of postlingually deaf or severely hearing-impaired patients (n = 54) served as a control. Cronbach's α and test-retest reliability were measured. The content, discrimination, and agreement validity were tested. The evaluation of construct validity was based on recently published data. Sensitivity and receiver operating curve (ROC) analysis, including consideration of the area under the curve (AUC), were used as quality criteria., Results: The test-retest analysis showed stable NCIQ values 3 and 6 months postoperatively. The Cronbach's α values indicated good internal consistency. The NCIQ validly discriminated between treated and untreated patient groups. There were statistically significant albeit weak correlations between the NCIQ and the APHAB (r = -0.22; p = 0.04) and the HPS (r = 0.30; p = 0.01). Sensitivity and ROC analyses showed good measurement quality of the German-speaking NCIQ., Conclusion: The German translation of the NCIQ reliably and validly measures HRQoL before and after cochlear implantation and can be used for clinical monitoring after treatment with cochlear implants., (© 2021. The Author(s).)

Background: The pathogenesis of head and neck squamous cell carcinoma (HNSCC) is a complex and multistage process which results from the interaction of exogenous and endogenous cellular processes. Each of these processes leaves a characteristic pattern of mutations on the tumor genome, a so-called mutational signature., State of the Art: The subject of current studies is to decipher specific signatures of mutational processes operating during HNSCC pathogenesis and to address their prognostic value. Computational analysis of genomic sequencing data by The Cancer Genome Atlas (TCGA) revealed mutational signatures 1, 2, 4, 5, 7, and 13 as the main players in HNSCC pathogenesis. Signature 16 was first discovered in human papillomavirus (HPV)-negative oral and oropharyngeal tumors. In many studies, an association of signature 16 with alcohol and tobacco consumption as well as with an unfavorable prognosis was described.

Adaptation to ecologically heterogeneous environments can drive speciation. But what mechanisms maintain reproductive isolation among locally adapted populations? Using poeciliid fishes in a system with naturally occurring toxic hydrogen sulfide, we show that (a) fish from non-sulfidic sites (Poecilia mexicana) show high mortality (95 %) after 24 h when exposed to the toxicant, while locally adapted fish from sulfidic sites (Poecilia sulphuraria) experience low mortality (13 %) when transferred to non-sulfidic water. (b) Mate choice tests revealed that P. mexicana females exhibit a preference for conspecific males in non-sulfidic water, but not in sulfidic water, whereas P. sulphuraria females never showed a preference. Increased costs of mate choice in sulfidic, hypoxic water, and the lack of selection for reinforcement due to the low survival of P. mexicana may explain the absence of a preference in P. sulphuraria females. Taken together, our study may be the first to demonstrate independent-but complementary-effects of natural and sexual selection against immigrants maintaining differentiation between locally adapted fish populations.

The majority of studies on ecological speciation in animals have investigated the divergence caused by biotic factors like divergent food sources or predatory regimes. Here, we examined a system where ecological speciation can clearly be ascribed to abiotic environmental gradients of naturally occurring toxic hydrogen sulfide (H(2)S). In southern Mexico, two genera of livebearing fishes (Poeciliidae: Poecilia and Gambusia) thrive in various watercourses with different concentrations of H(2)S. Previous studies have revealed pronounced genetic differentiation between different locally adapted populations in one species (Poecilia mexicana), pointing towards incipient speciation. In the present study, we examined female reproductive life-history traits in two species pairs: Gambusia sexradiata (from a nonsulfidic and a sulfidic habitat) and Gambusia eurystoma (sulfide-endemic), as well as P. mexicana (nonsulfidic and sulfidic) and Poecilia sulphuraria (sulfide endemic). We found convergent divergence of life-history traits in response to sulfide; most prominently, extremophile poeciliids exhibit drastically increased offspring size coupled with reduced fecundity. Furthermore, within each genus, this trend increased with increasing sulfide concentrations and was most pronounced in the two endemic sulfur-adapted species. We discuss the adaptive significance of large offspring size in toxic environments and propose that divergent life-history evolution may promote further ecological divergence through isolation by adaptation.

A fundamental question in sympatric speciation is how trophic divergence is achieved. We used an extremely young (<8,000 years) species flock of pupfish (Cyprinodon spp.) from Laguna Chichancanab in south-eastern Mexico to examine divergent evolution of preferences for different feeding substrates. In a test aquarium, we presented four feeding substrates (sand, gravel, a plastic plant, and blank bottom), but no actual food was offered. The four feeding substrates were chosen to mirror the most common substrate types in Laguna Chichancanab. Previous studies demonstrated that benthic food items prevail in the diet of most Cyprinodon species. C. beltrani preferred sand, whereas C. labiosus preferred gravel. F(1) hybrids of both species showed intermediate preferences. C. maya searched for food equally at all substrates. As the test fish were reared under identical laboratory conditions (i.e., in the absence of feeding substrates), the species-specific preferences appear to be genetically fixed, suggesting rapid divergent evolution of feeding behaviors.

Male-biased predation has been described from several epigean species, and in many cases, intrinsic differences between the sexes (such as male ornaments) have been suggested as an explanation. Here we report on male-biased predation of a cave fish (Poecilia mexicana) by an aquatic insect (Belostoma sp.) in a Mexican sulfur cave. P. mexicana use aquatic surface respiration (ASR) to survive in their sulfidic, hypoxic habitat. We found that males typically exhibit more ASR activity than females, which leads to increased exposure to the sit-and-wait predator that catches fish near the water surface. Our finding is novel, because male vulnerability to predation is not directly related to male traits involved in courtship, but rather due to other sexual differences in behavior and ultimately, oxygen demands.

Extreme habitats challenge animals with highly adverse conditions, like extreme temperatures or toxic substances. In this paper, we report of a fish (Poecilia mexicana) inhabiting a limestone cave in Mexico. Several springs inside the cave are rich in toxic H(2)S. We demonstrate that a behavioural adaptation, aquatic surface respiration (ASR), allows for the survival of P. mexicana in this extreme, sulphidic habitat. Without the possibility to perform ASR, the survival rate of P. mexicana was low even at comparatively low H(2)S concentrations. Furthermore, we show that food limitation affects the survival of P. mexicana pointing to energetically costly physiological adaptations to detoxify H(2)S.

Atlantic mollies (Poecilia mexicana) inhabit a variety of surface habitats, but they also occur in a sulfur cave in southern Mexico. We examined male mate choice relative to female body size in the cave population and in the most closely related surface-dwelling population from a nearby river. Males from both populations were either light- or dark-reared and could choose between two differently sized females either on the basis of visual cues in light or on the basis of solely nonvisual cues in darkness. Sexual preferences were estimated from the degree of association. Cave molly males always showed a preference for the larger female, both in light and in darkness. Among the surface males, only light-reared males showed a preference in the visual cues test, but not in darkness. In a control experiment, we demonstrated that male association preferences directly translate into actual mating preferences. Apparently, using visual cues for mate choice is the ancestral state in this system, and using nonvisual cues has evolved as a novel trait in the cave population. We discuss the evolution of nonvisual male mate choice in the context of changed environmental conditions, namely the absence of light, hypoxia, and toxic hydrogen sulfide in the cave.