More than one millennium (2nd-16th century CE) of the White Plague in the Carpathian Basin - New cases, expanding knowledge.

The causative agent of tuberculosis is still a widespread pathogen, which caused the death of ca. 1.6 million people globally in 2021. The paleopathological study of human remains revealed the antiquity of the disease and its continuous presence throughout the history of humankind. The Carpathian Basin has always been a biocultural melting pot, since it has seen several migrations over the centuries, and served as a location of admixture and interaction for numerous populations of different cultures. Thus, this geographical territory is ideal for the examination of the coevolutionary processes of hosts and their pathogens. We aimed to reveal the spatial and temporal distribution of tuberculosis cases excavated inside the borders of Hungary between the 2nd and 16th centuries CE. We established a comprehensive database by collecting 114 already published cases and introducing 39 new cases. The involved cases include those that have been confirmed by different molecular methods, as well as possible infections that were identified based on the presence of macromorphological and radiological alterations. The progress of future molecular and paleopathological studies can be facilitated by our dataset, as it presents spatial and temporal information concerning the spread of the disease in the Carpathian Basin, as well as the biological profile and detailed paleopathological description of lesions illustrated by photo- and radiographs.

Age-related changes in cochlear and brainstem auditory functions in Fischer 344 rats.

Auditory function in Fischer 344 (F344) and Long Evans (LE) rats was monitored during their lifespan by evaluating hair cell loss, middle-ear compliance and the recording of otoacoustic emissions and auditory brainstem responses. The results revealed a faster deterioration of hearing function in F344 rats compared with LE rats, resulting in larger hearing threshold shifts, a decrease in the latency and amplitude of click-evoked auditory brainstem responses, diminution of the distortion product otoacoustic emissions and a decrease in middle-ear compliance. However, hair cell loss, observed only at the most basal and apical parts of the organ of Corti, was comparable in older individuals of both rat strains. The results suggest involvement of cochlear (stria vascularis) and extracochlear (middle-ear) pathological changes during ageing. Thus, F344 rats represent a complex mix of conductive hearing loss (with low-frequency threshold shift, declining parameters of the middle-ear admittance and asymmetric otoacoustic emissions) and sensorineural hearing loss (with a decrease in the amplitudes of auditory brainstem response and a high-frequency threshold shift).

Changes in otoacoustic emissions and high-frequency hearing thresholds in children and adolescents.

With the aim of characterizing the loss of high frequency hearing sensitivity in children, hearing thresholds and otoacoustic emissions were measured in a group of 126 normal hearing children and adolescents aged from 6 to 25 years. The subjects were divided into four 5-year age groups. Hearing thresholds over a range of 125 Hz-12.5 kHz were similar in all age groups, the average hearing threshold at 16 kHz was significantly elevated in the oldest age group. The response values of transiently evoked otoacoustic emissions (TEOAEs) significantly declined with age; the decline was negatively correlated with the hearing loss at 16 kHz. Significantly larger TEOAE responses and average distortion-product otoacoustic emission (DPOAE) values at 6.3 kHz were present in the youngest group in comparison with the other three older groups. Spontaneous otoacoustic emissions (SOAEs) were present in 70.8% of the children (in either one or both ears) with the greatest prevalence in the 11-20-year-old subjects. In the 21-25-year-old group, the hearing loss at 16 kHz was significantly smaller in ears with SOAEs than in ears without SOAEs. The results demonstrate that the increase in the high frequency hearing threshold at 16 kHz, which starts at ages over 20 years, is correlated with a decrease in the TEOAE responses at middle frequencies.

Mutations in eight small DFNB genes are not a frequent cause of non-syndromic hereditary hearing loss in Czech patients.

OBJECTIVES: To evaluate the contribution of eight small NSHL-AR (non-syndromic deafness, autosomal recessive) genes to hereditary hearing loss in Czech patients. PATIENTS AND METHODS: Unrelated Czech patients, adults and children, diagnosed with pre-lingual hereditary hearing loss with at least one similarly affected deaf sibling and with previously excluded mutations in the GJB2 gene were investigated by Sanger sequencing of the selected eight small NSHL-AR associated genes (CABP2 - 51 patients, CIB2 - 45 patients, PJVK/DFNB59 - 53 patients, GJB3 - 46 patients, ILDR1 - 48 patients, LHFPL5 - 66 patients, LRTOMT - 60 patients, TMIE - 64 patients). RESULTS: Mutations were detected in the LHFPL5 (DFNB67) gene. The patient is heterozygote for two already described pathogenic variants (p.Tyr127Cys, p.Thr165Met). In five samples, five rare heterozygous variants (two novel) predicted as pathogenic were detected in genes CABP2, ILDR1, LHFPL5 and LRTOMT. CONCLUSION: Mutations in eight small NSHL-AR genes are not a frequent cause of hereditary hearing loss in the Czech Republic. This diagnostic approach permitted the clarification of HL in only one patient - two heterozygous mutations were detected in LHFPL5 gene for the first time in Central Europe. As the use of panel base MPS certainly improves the diagnostic yield, future studies should rather profit from that diagnostic strategy.

Cochlear function in young and adult Fischer 344 rats.

Fischer 344 (F344) rats are often used as an animal model for investigation of the mechanisms underlying age-related hearing loss. The aim of this study was to assess cochlear function in young (1-month-old) and adult (6-month-old) F344 rats using recording of otoacoustic emissions and auditory brainstem responses (ABRs). The results were compared with control groups of Long Evans (LE) rats of the same ages. The results demonstrate a significant increase in the hearing threshold in F344 rats in comparison with LE rats, expressed mainly at low frequencies (1-2 kHz). In F344 rats, transient evoked otoacoustic emissions were not measurable and distortion product otoacoustic emissions could be detected within a frequency range of 2.4-6.3 kHz. Tympanometric measurements did not reveal any differences in middle ear parameters between F344 and LE rats. The amplitudes of click-evoked ABRs were significantly lower in 6-month-old F344 rats than in LE rats, but other parameters of the ABRs were almost identical in both rat strains. The results demonstrate a significant deficit in low-frequency hearing and altered otoacoustic emissions in both young and adult F344 rats, suggesting a defect of the inner ear sensory epithelium at the apical part of the cochlea.

Bioactive glasses with improved processing. Part 1. Thermal properties, ion release and apatite formation.

Bioactive glasses, particularly Bioglass® 45S5, have been used to clinically regenerate human bone since the mid-1980s; however, they show a strong tendency to undergo crystallization upon heat treatment, which limits their range of applications. Attempts at improving their processing (by reducing their tendency to crystallize) have included increasing their silica content (and thus their network connectivity), incorporating intermediate oxides or reducing their phosphate content, all of which reduce glass bioactivity. Therefore, bioactive glasses known for their good processing (e.g. 13-93) are considerably less bioactive. Here, we investigated if the processing of 45S5 bioactive glass can be improved while maintaining its network connectivity and phosphate content. The results show that, by increasing the calcium:alkali cation ratio, partially substituting potassium for sodium (thereby making use of the mixed alkali effect) and adding small amounts of fluoride, bioactive glasses can be obtained which have a larger processing window (suggesting that they can be processed more easily, allowing for sintering of scaffolds or drawing into fibres) while degrading readily and forming apatite in aqueous solution within a few hours.

Bacterial infection complications in children with cochlear implants in the Czech Republic.

OBJECTIVE: Studies describing wound infections after cochlear implantation are rare. Meticulous operative techniques and sufficient surgical skill can help to avoid severe postoperative complications. Minor complications such as seromas, superficial wound infections, skin emphysema, and swelling can all be successfully treated using conservative methods. Serious problems, however, could be caused by Pseudomonas aeruginosa and Staphylococcus aureus infections. STUDY DESIGN: Retrospective case series. SETTING: Pediatric cochlear implant center in the Czech Republic. RESULTS: In our cohort of 360 children operated on between 1994 and 2009, there were no major surgical complications. However, there were four serious wound infections, two of which resulted in explantation of the device. Two patients with a well-bordered abscess formation were successfully treated with antibiotics and drainage. Explantation was required in another two children with refractory P. aeruginosa infection. Despite favorable sensitivity to a number of antibiotics, intravenous and intensive local treatment failed. After explantation, the operative sites healed immediately. Both children were successfully implanted contralaterally 6 months later. Detailed bacteriological tests from different parts of the device were performed. CONCLUSION: The consequences of explantation were discussed in our cochlear implant center. Confirmed by the microbiological results and reports in the scientific literature, it seems preferable to cut the electrode near the cochlear array and leave it inside the cochlea in order to use the same ear for reimplantation at a later date.