Auditory-Nerve Responses in Mice with Noise-Induced Cochlear Synaptopathy

Cochlear synaptopathy is the noise-induced or age-related loss of ribbon synapses between inner hair cells (IHCs) and auditory nerve fibers (ANFs), first reported in CBA/CaJ mice. Recordings from single ANFs in anaesthesized, noise-exposed guinea pigs suggested that neurons with low spontaneous rates (SRs) and high thresholds are more vulnerable than low-threshold, high-SR fibers. However, there is extensive post-exposure regeneration of ANFs in guinea pigs, but not in mice. Here, we exposed CBA/CaJ mice to octave-band noise and recorded sound-evoked and spontaneous activity from single ANFs at least 2 weeks later. Confocal analysis of cochleae immunostained for pre- and post-synaptic markers confirmed the expected loss of 40 - 50% of ANF synapses in the basal half of the cochlea, however, our data were not consistent with a selective loss of low-SR fibers. Rather they suggested a loss of both SR groups in synaptopathic regions. Single-fiber thresholds and frequency tuning recovered to pre-exposure levels however, response to tone bursts showed increased peak and steady-state firing rates as well as decreased jitter in first-spike latencies. This apparent gain-of-function increased the robustness of tone-burst responses in the presence of continuous masking noise. This study suggests that the nature of noise-induced synaptic damage varies between different species and that, in mouse, the noise-induced hyperexcitability seen in central auditory circuits is also observed at the level of the auditory nerve.

A new species of the genus Cerapanorpa (Mecoptera, Panorpidae) from the eastern Bashan Mountains

Cerapanorpa Gao, Ma & Hua, 2016, an endemic genus of Panorpidae in central China’s mountain regions, currently comprises 21 described species. Recently, the short-horned scorpionfly C. brevicornis (Hua & Li, 2007) was confirmed to contain two valid species by phylogeographic and morphological data. Individuals from the highlands of the eastern Bashan Mountains were suggested as a good species, separated from the original short-horned C. brevicornis. Cerapanorpa alpinasp. nov. was described from the alpine zone of the eastern Bashan Mountains in central China. The new species differs from its congeners by the following combination of characters: male bearing an extra-short anal horn on posterior margin of tergum VI; paramere elongate, extending beyond the median tooth of gonostylus and curved laterally at basal half; female medigynium slightly constricted medially without dorsal basal plate. The species number of Cerapanorpa is raised to 22.

Continuous Facial Nerve Stimulation During Cochlear Implantation – An Electrophysiological Technique to Control the Intracochlear Electrode Contact Position

Purpose: This proof of concept describes the use of evoked electromyographic (EMG) activation of the facial nerve for intraoperative monitoring of the electrode insertion during cochlear implantation (CI).Methods: Intraoperative EMG measurements from the facial nerve were conducted in nine patients undergoing CI implantation. Electric pulses were emitted from contacts on the CI array during and immediately after electrode insertion. For control, the results of EMG measurements were compared to postoperative flat panel volume computed tomography scans with secondary reconstruction (fpVCTSECO).Results: During insertion, the EMG response evoked by the electrical stimulation from the CI was growing with the stimulating contact approaching the facial nerve and declined with increasing distance. After full insertion, contacts on the apical half of the CI array stimulated higher EMG responses compared with those on the basal half. Comparison with postoperative imaging demonstrated that electrode contacts stimulating high EMG responses had the shortest distances to the facial nerve. Conclusion: It could be demonstrated that electrically evoked EMG activation of the facial nerve can be used to monitor the progress during CI electrode insertion and to control the intracochlear electrode position after full insertion.

A new species of the genus Petersenidia Lelej (Hymenoptera: Mutillidae) from Indonesia, eastward of Wallace’s line

Petersenidia mikhailovi sp. nov. (♀, Indonesia: Sulawesi) is described and illustrated. The new species is related to P. macassarica (Zavattati, 1914) by having a median longitudinal carina on the basal half of metasomal tergum 2, but differs by the carina being shorter and lower, by the lack of a posterior interrupted pale fringe on metasomal tergum 2 and by a smooth pygidium. The lectotype of Mutilla macassarica Zavattari, 1914 is designated.

A unique, large-sized stem Odonata (Insecta) found in the early Pennsylvanian of New Brunswick (Canada)

A stem relative of dragon- and damselflies, Brunellopteron norradi Béthoux, Deregnaucourt and Norrad gen. et sp. nov., is documented based on a specimen found at Robertson Point (Grand Lake, New Brunswick, Canada; Sunbury Creek Formation; early Moscovian, Pennsylvanian) and preserving the basal half of a hindwing. A comparative analysis of the evolution of wing venation in early odonates demonstrates that it belongs to a still poorly documented subset of species. Specifically, it displays a MP + CuA fusion, a CuA + CuP fusion, and a CuP + AA fusion, but it lacks the “extended” MP + Cu / CuA fusion and the “extended” (CuP / CuA + CuP) + AA fusion, the occurrence of which is typical of most Odonata, including Meganeura-like species. The occurrence of intercalary veins suggests that its closest relative might be Gallotypus oudardi Nel, Garrouste and Roques, 2008, from the Moscovian of northern France.

Classification of the sperm chromatin compaction alterations in bulls (Bos taurus) and its correlation with the efficiency of the in vitro production of embryos

This paper proposes to classify the sperm chromatin compaction alterations in bulls, according to the affected area location and its objective is evaluating the correlation of the intensity, the heterogeneity and these kinds of chromatin decompaction with the rates of cleavage and the formation of blastocysts of in vitro production of embryos (IVPE). It was used several subfertile animals sperm samples, which were evaluated using the toluidine blue staining and computer image analysis, making possible the categorization of the chromatin decompaction according to their location. The percentages of chromatin decompaction and heterogeneity were also evaluated. IVPEs were done and the rates of cleavage and of blastocysts were correlated with the chromatin characteristics. It made possible the classification of the chromatin decompaction according to the head affected part in at least four types: base decompaction, basal half decompaction, central axis decompaction, total decompaction. Based on the correlation, it can be implicated that each type of classification has different influences on the bull fertility. It made possible understanding that sperms amount with 5% or more of chromatin decompaction intensity interferes in the bull fertility and this condition can be featured as an uncompensable defect, while the heterogeneity of chromatin is not an important factor in the IVPE results.

Rapamycin Added to Diet in Late Mid-Life Delays Age-Related Hearing Loss in UMHET4 Mice

Our previous study demonstrated rapamycin added to diet at 4 months of age had significantly less age-related outer hair cell loss in the basal half of the cochlea at 22 months of age compared to mice without rapamycin. The present study tested adding rapamycin to diet later in life, at 14 months of age, and added a longitudinal assessment of auditory brain stem response (ABR). The present study used UMHET4 mice, a 4 way cross in which all grandparental strains lack the Cdh23753A allele that predisposes to early onset, progressive hearing loss. UMHET4 mice typically have normal hearing until 16–17 months, then exhibit threshold shifts at low frequencies/apical cochlea and later in more basal high frequency regions. ABR thresholds at 4, 12, 24, and 48 kHz were assessed at 12, 18, and 24 months of age and compared to baseline ABR thresholds acquired at 5 months of age to determine threshold shifts (TS). There was no TS at 12 months of age at any frequency tested. At 18 months of age mice with rapamycin added to diet at 14 months had a significantly lower mean TS at 4 and 12 kHz compared to mice on control diet with no significant difference at 24 and 48 kHz. At 24 months of age, the mean 4 kHz TS in rapamycin diet group was no longer significantly lower than the control diet group, while the 12 kHz mean remained significantly lower. Mean TS at 24 and 48 kHz in the rapamycin diet group became significantly lower than in the control diet group at 24 months. Hair cell counts at 24 months showed large loss in the apical half of most rapamycin and control diet mice cochleae with no significant difference between groups. There was only mild outer hair cell loss in the basal half of rapamycin and control diet mice cochleae with no significant difference between groups. The results show that a later life addition of rapamycin can decrease age-related hearing loss in the mouse model, however, it also suggests that this decrease is a delay/deceleration rather than a complete prevention.

Two new genera of Desmiphorini (Coleoptera, Cerambycidae, Lamiinae) with description of a species with non-retractile parameres

In this study, two new genera of Desmiphorini (Lamiinae) are proposed: Cleidaria gen. nov., to include Cleidaria cleidae sp. nov. from the state of Chiapas in Mexico, and Obscenoides gen. nov. for Desmiphora (D.) compta Martins & Galileo, 2005. The shape of tarsal claws of Cleidaria cleidae sp. nov. (abruptly narrowed from basal half) is so far, not found in any current genera of the tribe. With respect to Obscenoides compta (Martins & Galileo, 2005) comb. nov., the genitalia of males have an unusual shape with non-retractile parameres. The character combination related to this genital structure is unknown to us in other species in the family, and hypotheses about its function are suggested.

A new species of Chiridurothrips Okajima from Miocene amber of the Dominican Republic (Thysanoptera: Phlaeothripidae)

The thysanopteran genus Chiridurothrips Okajima is known from a single extant species, C. hisakoae Okajima, collected in Japan (ThripsWiki 2019). Occurring on dead leaves and branches of evergreen trees in the subtropical Ryukyu Islands, this species remains known from only five females (Okajima 1981, 2006; also pers. comm. 2018). Within Phlaeothripidae, Chiridurothrips is associated with the tribe Plectrothripini. Species of this sub-group feed on fungal hyphae or the break-down products of fungal attack on decaying plant material (Mound & Ng 2018). They are found mainly under the bark of trees or on dead branches, and they do not seem to inhabit leaf-litter (Okajima 1981). At present, Plectrothripini comprises 60 extant species in 13 genera, with no fossils recorded. Of these species 32 are placed in the genus Plectrothrips Hood, ten in Streptothrips Priesner, and six in Chirothripoides Bagnall, whereas both Menothrips Hood and Mastigothrips Priesner each include only two species. The remaining eight species are all placed in separate monobasic genera (ThripsWiki 2019). Concerning this strongly asymmetric classification, Mound and Ng (2018) suggest that Plectrothripini might be particularly old, with the large number of monobasic genera each representing a relict lineage. An alternative possibility, however, might be an unusual instability in the genes controlling morphogenetic processes, and thus resulting in striking autapomorphies on which each one of these genera is diagnosed (Mound & Ng 2018). Species associated with Plectrothripini share the following character states (Okajima 1981; Mound & Tree 2017): antennae 8-segmented, segment II with the campaniform sensillum situated in the basal half, III–IV with stout sense cones, VIII slender with narrow base; head with posterior ocelli close to compound eyes; pronotum commonly with sclerotized plate eroded or reduced, prosternal basantra week or absent; legs with fore tarsal tooth large; mid and hind tibiae commonly with apical spur-like setae; macropterae with fore wings parallel-sided, usually with duplicated cilia; pelta broad at base, abdominal tergite II eroded laterally; abdominal sternites often with reticulate glandular areas. Regarding the fore wings, it seems worth mentioning that in some members of Plectrothripini the subbasal wing vein is reduced and thus the three subbasal wing setae are lacking (see Plectrothrips tenuis Okajima, Chiridurothrips [c.f. fig. 2], Chirothripoides, Lonchothrips Hood; Bhatti 1998; Okajima 1981). This short vein that is present in (almost all) other macropterous Phlaeothripidae has been interpreted as a plesiomorphic feature that resulted from the reduction of a former well-developed longitudinal first vein of ancestral Tubulifera, the Rohrthripidae (Ulitzka 2018, 2019).

Waidelotinae, a new subfamily of Pyrochroidae (Coleoptera: Tenebrionoidea) from Baltic amber of the Sambian peninsula and the interpretation of Sambian amber stratigraphy, age and location

Waidelotus hoffeinsorum gen. et sp. nov. is described from Eocene Baltic amber and assigned to Waidelotinae subfam. nov. within family Pyrochroidae (Coleoptera). The new subfamily differs from the other subfamilies by the following combination of features: penultimate tarsomere of all tarsi deeply bilobed, antepenultimate tarsomere of each pro- and mesothoracic tarsus slightly bilobed, antepenultimate tarsomere of metathoracic tarsi slightly widened apically; pronotum laterally margined in basal half; eyes emarginate; pretarsal claws appendiculate; prosternal intercoxal process incompletely separating prothoracic coxae; pronotum with fine posterior submarginal groove; head without distinct constriction behind eyes; posterior pronotal pits absent; and elytral pubescence homogenous. It is the only authentic species of Pyrochroidae (Coleoptera) from Baltic amber, pending final placement of Palaeopyrochroa crowsoni Abdullah, 1965. Additionally, the available data on stratigraphy of amber-bearing strata on the Sambian peninsula, and the age and location of Eocene amberiferous forests are discussed. A middle Eocene (mostly Bartonian) age is interpreted for the extinct Central European resin-producing forests resulting in the Sambian amber deposits.