The Bonebridge system – Our clinical experience /Case report/

Introduction: Bone conduction implants are a standard treatment option for patients with conductive or mixed, hearing loss. The Bonebridge system was introduced by MED-EL in 2012, and two years after its debut, it was used in more than 200 centers worldwide (6). For the first time the Bonebridge system was implanted in Bulgaria in 2015 by associated professor P. Rouev. The main audiological criteria for placement is conductive hearing loss, which is caused by atresia of the auditory canal or diseases of the middle ear with preserved bone conduction (below 45 dB), as well as unilateral hearing loss above 70 dB (contralateral hearing loss not more than 20 dB). The system does not penetrate the skin and consists of an internal part - an implant, which is placed completely under the skin, and an external part - a processor. The acoustic signal from the environment is transformed into mechanical vibrations that are transmitted to the mastoid bone. The expected results are an improved hearing threshold and better hearing in noisy environments.Methods: Our clinical experience with the Bonebridge system is based on three operated patients aged between 56 and 73 years. All three patients had evidence of bilateral conductive hearing loss. Here we present one of these cases.Results: Test results showed significant improvement in hearing sensitivity especially in frequencies round 1000 Hz.Conclusions: Bone conduction implants such as the Bonebridge system are an excellent treatment option for patients with bilateral conductive deafness. Bonebridge has good hearing results, relative simplicity, and low rate of complications. Experience has shown that the Bonebridge system is easy to use and highly reliable. The use of Bonebridge conduction implant system leads to a significant improvement in the quality of life

The subgroup identification problem for finitely presented groups

We introduce the subgroup identification problem, and show that there is a finitely presented group G for which it is unsolvable, and that it is uniformly solvable in the class of finitely presented locally Hopfian groups. This is done as an investigation into the difference between strong and weak effective coherence for finitely presented groups.Comment: 11 pages. This is the version submitted for publicatio

Decidability of membership problems for flat rational subsets of GL(2, Q) and singular matrices

This work relates numerical problems on matrices over the rationals to symbolic algorithms on words and finite automata. Using exact algebraic algorithms and symbolic computation, we prove new decidability results for 2 × 2 matrices over Q. Namely, we introduce a notion of flat rational sets: if M is a monoid and N ≤ M is its submonoid, then flat rational sets of M relative to N are finite unions of the form L0g1 L1 ··· gtLt where all Lis are rational subsets of N and gi ∈ M. We give quite general sufficient conditions under which flat rational sets form an effective relative Boolean algebra. As a corollary, we obtain that the emptiness problem for Boolean combinations of flat rational subsets of GL(2, Q) over GL(2, Z) is decidable. We also show a dichotomy for nontrivial group extension of GL(2, Z) in GL(2, Q): if G is a f.g. group such that GL(2, Z) < G ≤ GL(2, Q), then either G ≅ GL(2, Z) × Zk, for some k ≥ 1, or G contains an extension of the Baumslag-Solitar group BS(1, q), with q ≥ 2, of infinite index. It turns out that in the first case the membership problem for G is decidable but the equality problem for rational subsets of G is undecidable. In the second case, decidability of the membership problem is open for every such G. In the last section we prove new decidability results for flat rational sets that contain singular matrices. In particular, we show that the membership problem is decidable for flat rational subsets of M(2, Q) relative to the submonoid that is generated by the matrices from M(2, Z) with determinants 0, ± 1 and the central rational matrices

Novel merwinite/akermanite ceramics: in vitro bioactivity

The ceramics in the system CaO – MgO – SiO2 has recently received a great deal of attention because they exhibit good in vitro bioactivity and have potential use as bone implants. Biphasic calcium-magnesium-silicate ceramics was prepared by a sol-gel method. The dried gel with chemical composition 3CaO.MgO.2SiO2 was thermally treated at 1300°C for 2 h. The structural behavior of the synthesized ceramics was examined by means of X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). Merwinite, as the main crystalline phase, and akermanite, as the minor phase, were identified. The in vitro bioactivity of the synthesized ceramic samples was recorded in Simulated Body Fluid (SBF) for different times of soaking. The apatite formation on the surface of the immersed samples was detected by FTIR, SEM and Energy Dispersive Spectroscopy (EDS) techniques. The ion concentrations in the SBF solutions after the in vitro test were evaluated by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). On the basis of the results obtained, the ability of the biphasic ceramics to deposit apatite layer was found. The peculiarities of the formation of apatite layer depending on the phase composition were analyzed and discussed

Association of Epstein-Barr virus antibody titers with a human IL-10 promoter polymorphism in Japanese women

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High-Coverage Whole-Exome Sequencing Identifies Candidate Genes for Suicide in Victims with Major Depressive Disorder

We carried out whole-exome ultra-high throughput sequencing in brain samples of suicide victims who had suffered from major depressive disorder and control subjects who had died from other causes. This study aimed to reveal the selective accumulation of rare variants in the coding and the UTR sequences within the genes of suicide victims. We also analysed the potential effect of STR and CNV variations, as well as the infection of the brain with neurovirulent viruses in this behavioural disorder. As a result, we have identified several candidate genes, among others three calcium channel genes that may potentially contribute to completed suicide. We also explored the potential implication of the TGF-β signalling pathway in the pathogenesis of suicidal behaviour. To our best knowledge, this is the first study that uses whole-exome sequencing for the investigation of suicide

Rapid Selection and Proliferation of CD133(+) Cells from Cancer Cell Lines: Chemotherapeutic Implications

Cancer stem cells (CSCs) are considered a subset of the bulk tumor responsible for initiating and maintaining the disease. Several surface cellular markers have been recently used to identify CSCs. Among those is CD133, which is expressed by hematopoietic progenitor cells as well as embryonic stem cells and various cancers. We have recently isolated and cultured CD133 positive [CD133(+)] cells from various cancer cell lines using a NASA developed Hydrodynamic Focusing Bioreactor (HFB) (Celdyne, Houston, TX). For comparison, another bioreactor, the rotary cell culture system (RCCS) manufactured by Synthecon (Houston, TX) was used. Both the HFB and the RCCS bioreactors simulate aspects of hypogravity. In our study, the HFB increased CD133(+) cell growth from various cell lines compared to the RCCS vessel and to normal gravity control. We observed a (+)15-fold proliferation of the CD133(+) cellular fraction with cancer cells that were cultured for 7-days at optimized conditions. The RCCS vessel instead yielded a (−)4.8-fold decrease in the CD133(+)cellular fraction respect to the HFB after 7-days of culture. Interestingly, we also found that the hypogravity environment of the HFB greatly sensitized the CD133(+) cancer cells, which are normally resistant to chemo treatment, to become susceptible to various chemotherapeutic agents, paving the way to less toxic and more effective chemotherapeutic treatment in patients. To be able to test the efficacy of cytotoxic agents in vitro prior to their use in clinical setting on cancer cells as well as on cancer stem cells may pave the way to more effective chemotherapeutic strategies in patients. This could be an important advancement in the therapeutic options of oncologic patients, allowing for more targeted and personalized chemotherapy regimens as well as for higher response rates

Titanium silicalite-1 macrostructures for photocatalytic removal of organic pollutants from aqueous media

Titanium silicalite-1 (TS-1) structures in the form of macroscopic beads with hierarchical porosity were prepared by the resin templating method. The Ti content within the samples was varied between 1 and 7 wt%, with corresponding surface areas ranging from 725 to 350 m2 g−1, respectively. The samples contained a large amount of amorphous material, which was necessary to achieve high mechanical stability of the beads. The TS-1 macrostructures were used as catalysts for the photocatalytic degradation of methylene blue (MB), and results were compared to the results for a commercial anatase nanopowder (CristalACTiV™ PC500). All TS-1 beads showed similar MB degradation rates independently of their Ti content, which was linked to variations in the surface areas and structure. The macroscopic shape of the TS-1 beads allowed easy recovery from the mother liquor upon decolouration of the MB solutions, which was highly beneficial compared to the reference anatase nanopowder. The TS-1 beads could be reused in subsequent photocatalytic cycles after decanting exhausted solutions and replacing with fresh MB solutions without any energy-consuming regeneration steps involved. The samples were tested in five consecutive cycles and MB degradation rates remained broadly unchanged during all tests