Response to 'Monotreme middle ear is not primitive for Mammalia'.
Ontology highlight
ABSTRACT:
SUBMITTER: Wible JR
PROVIDER: S-EPMC8566169 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description: Not available
| S-EPMC8566185 | biostudies-literature
Project description:Bats are the only mammals capable of powered flight. One of the oldest bats known from a complete skeleton is Onychonycteris finneyi from the Early Eocene (Green River Formation, Wyoming, 52.5 Ma). Estimated to weigh approximately 40 g, Onychonycteris exhibits the most primitive combination of characters thus far known for bats. Here, we reconstructed the aerofoil of the two known specimens, calculated basic aerodynamic variables and compared them with those of extant bats and gliding mammals. Onychonycteris appears in the edges of the morphospace for bats, underscoring the primitive conformation of its flight apparatus. Low aerodynamic efficiency is inferred for this extinct species as compared to any extant bat. When we estimated aerofoil variables in a model of Onychonycteris excluding the handwing, it closely approached the morphospace of extant gliding mammals. Addition of a handwing to the model lacking this structure results in a 2.3-fold increase in aspect ratio and a 28% decrease in wing loading, thus greatly enhancing aerodynamics. In the context of these models, the rapid evolution of the chiropteran handwing via genetically mediated developmental changes appears to have been a key transformation in the hypothesized transition from gliding to flapping in early bats.
| S-EPMC6451380 | biostudies-literature
Project description:Objective: Otitis media is known to alter expression of cytokine and other genes in the mouse middle ear and inner ear. However, whole mouse genome studies of gene expression in otitis media have not previously been undertaken. Ninety-nine percent of mouse genes are shared in the human, so these studies are relevant to the human condition. Methods: To assess inflammation-driven processes in the mouse ear, gene chip analyses were conducted on mice treated with trans-tympanic heat-killed Hemophilus influenza using untreated mice as controls. Middle and inner ear tissues were separately harvested at 6 hours, RNA extracted, and samples for each treatment processed on the Affymetrix 430 2.0 Gene Chip for expression of its 34,000 genes. Results: Statistical analysis of gene expression compared to control mice showed significant alteration of gene expression in 2,355 genes, 11% of the genes tested and 8% of the mouse genome. Significant middle and inner ear upregulation (fold change >1.5, p<0.05) was seen in 1,081 and 599 genes respectively. Significant middle and inner ear downregulation (fold change <0.67, p<0.05) was seen in 978 and 287 genes respectively. While otitis media is widely believed to be an exclusively middle ear process with little impact on the inner ear, the inner ear changes noted in this study were numerous and discrete from the middle ear responses. This suggests that the inner ear does indeed respond to otitis media and that its response is a distinctive process. Numerous new genes, previously not studied, are found to be affected by inflammation in the ear. Conclusion: Whole genome analysis via gene chip allows simultaneous examination of expression of hundreds of gene families influenced by inflammation in the middle ear. Discovery of new gene families affected by inflammation may lead to new approaches to the study and treatment of otitis media. There are 8 control samples and 9 samples trans-tympanically injected with H flu 10e9 for 6 hours. Each sample is from a single animal.
2013-07-23 | E-GEOD-49128 | biostudies-arrayexpress
Project description:NTHi bacteria or saline were inoculated into the middle ears of mice. Mice were sacrificed at various times to monitor the course of infection. We used Mouse430_2 arrays to profile gene expression in response to bacterial infection RNA extracted at sacrifice
2015-09-01 | E-GEOD-66141 | biostudies-arrayexpress
Project description:The transfer function H(V) between stapes velocity V(S) and sound pressure near the tympanic membrane P(TM) is a descriptor of sound transmission through the middle ear (ME). The ME power transmission efficiency (MEE), the ratio of sound power entering the cochlea to power entering the middle ear, was computed from H(V) measured in seven chinchilla ears and previously reported measurements of ME input admittance Y(TM) and ME pressure gain G(MEP) [Ravicz and Rosowski, J. Acoust. Soc. Am. 132, 2437-2454 (2012); J. Acoust. Soc. Am. 133, 2208-2223 (2013)] in the same ears. The ME was open, and a pressure sensor was inserted into the cochlear vestibule for most measurements. The cochlear input admittance Y(C) computed from H(V) and G(MEP) is controlled by a combination of mass and resistance and is consistent with a minimum-phase system up to 27 kHz. The real part Re{Y(C)}, which relates cochlear sound power to inner-ear sound pressure, decreased gradually with frequency up to 25 kHz and more rapidly above that. MEE was about 0.5 between 0.1 and 8 kHz, higher than previous estimates in this species, and decreased sharply at higher frequencies.
| S-EPMC3805178 | biostudies-other
Project description:A comparative study of ossicular reconstrution using four different graft material was carried out on 40 patients as a second stage procedure from July 1989 to June 1991. The graft materials used were : aulologus ossicular bone graft, allogeneic ossicular bone graft, autologus cartilage and bio-compatible materials. All patients were observed for a period ranging from one to two years. Extrusion of ossicular graft was prevented by use of a lace of cartilage between the ossicular graft and neotympanic membrance. Satisfactory results were obtained with cartilage graft in 6%, allogeneic ossicles 70%, autologus ossicular graft 80% and bio-compatible materials 33.3%.
| S-EPMC5529717 | biostudies-other
Project description:Middle ear diseases in childhood play an important role in daily ENT practice due to their high incidence. Some of these like acute otitis media or otitis media with effusion have been studied extensively within the last decades. In this article, we present a selection of important childhood middle ear diseases and discuss the actual literature concerning their treatment, management of complications and outcome. Another main topic of this paper deals with the possibilities of surgical hearing rehabilitation in childhood. The bone-anchored hearing aid BAHA(®) and the active partially implantable device Vibrant Soundbridge(®) could successfully be applied for children. In this manuscript, we discuss the actual literature concerning clinical outcomes of these implantable hearing aids.
| S-EPMC4273172 | biostudies-other
Project description:Chronic Otitis Media (OM) develops after sustained inflammation and is characterized by secretory middle ear epithelial metaplasia and effusion, most frequently mucoid. Non-typeable Haemophilus influenzae (NTHi), the most common acute OM pathogen, is known to activate inflammation and mucin expression in vitro and in animal models of OM. The goals of this study were to: examine expression profiling epithelial effects of NTHi challenge in murine middle ears. We used microarrays to detail examine the global programme of gene expression underlying epithelial effects of NTHi challenge in murine middle ears during this study. Weekly transtympanic inoculation of Balb/c mice with 300 µg/ml of NTHi lysates vs saline was performed. Bacteria were grown on chocolate agar at 37ºC in 5% CO2 overnight and inoculated in brain heart infusion (BHI) broth supplemented with 3.5 mg of nicotinamide adenine dinucleotide per ml. After overnight incubation, bacteria were subcultured into 5 ml of fresh brain heart infusion (BHI) and upon reaching log phase growth, NTHi were washed and suspended in phosphate-buffered saline (PBS) followed by sonication for lysis. Three transtympanic inoculation of 6 Balb/c mice middle ears (3 animals, 6 ears) with 50 uL of 300 ug/ml of NTHi bacterial lysate and 6 Balb/c mice middle ears (3 animals, 6 ears) with 50 uL of 1X phosphate buffered saline (PBS) were carried out weekly over 4 weeks (injection on days 7, 14, and 21). On day 28, the mice were euthanized and their bullae harvested. Expression microarray analysis was performed at 1 and 7 days. Microarray findings were validated in independent animal samples and in a cultured murine middle ear epithelial cell (mMEEC) line.
2012-11-13 | E-GEOD-40087 | biostudies-arrayexpress
Project description:Nontypeable Haemophilus influenzae (NTHi) is a major pathogen causing acute otitis media (AOM). The pathology of AOM increases during long-term infection in the middle ear (ME), but the host cellular immune response to bacterial infection in this inflamed environment is poorly understood. Using the Junbo mouse, a characterized NTHi infection model, we analyzed the cellular response to NTHi infection in the Junbo mouse middle ear fluid (MEF). NTHi infection increased the total cell number and significantly decreased the proportion of live cells in the MEF at day 1, and this further decreased gradually on each day up to day 7. Flow cytometry analysis showed that neutrophils were the dominant immune cell population in the MEF and that NTHi infection significantly increased their proportion whereas it decreased the monocyte, macrophage, and dendritic cell proportions. Neutrophil and macrophage numbers increased in blood and spleen after NTHi infection. The T-cell population was dominated by T-helper (Th) cells in noninoculated MEF, and the effector Th (CD44+) cell population increased at day 2 of NTHi infection with an increase in IL-12p40 levels. Sustained NTHi infection up to 3?days increased the transforming growth factor ? levels, decreasing the effector cell population and increasing the T-regulatory (T-reg) cell population. In the preinflamed ME environment of the Junbo mouse, neutrophils are the first responder to NTHi infection followed by T-reg immune suppressive cells. These data indicate that sustained NTHi infection in the ME induces the immune suppressive response by inducing the T-reg cell population and reducing immune cell infiltration, thus promoting longer-term infection.
| S-EPMC6867859 | biostudies-literature
Project description:NTHi bacteria or saline were inoculated into the middle ears of mice. Mice were sacrificed at various times to monitor the course of infection. We used Mouse430_2 arrays to profile gene expression in response to bacterial infection
2015-09-01 | GSE66141 | GEO