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PURPOSE: In recent years, new techniques have been added to cholesteatoma surgery, and established microsurgical approaches are being reconsidered. This study aims to present the importance of individualized decision-making for the selection of an intact canal wall (CWU) or canal wall down (CWD) surgical procedure for each patient. METHODS: Using the "ChOLE" classification we categorized 264 operations retrospectively. 162 CWU and 102 CWD surgeries were performed. We focus to determine why a CWD procedure was chosen quite frequently despite some low-stage cases. Furthermore, we evaluated recidivism and hearing outcomes. RESULTS: Smaller cholesteatomas (Ch-stage 1a, 1b & 2a) were found in 182 patients (70%), ossicular chain status feasible for straightforward reconstruction (O-stage 0, 1 & 2) was present in 186 patients (70%), minor complications due to the cholesteatoma (L-stage 1) were infrequent with 28 cases (11%) and a well-pneumatized mastoid was found in 144 cases (55%). Recidivism rates were low (7%) without any difference in both groups and a mean follow-up time of 4 years and 8 months. In primary surgeries there was a significant difference (p < 0.05) in postoperative mean air-bone gap (ABG) between CWU (17dB) and CWD (27dB). CONCLUSION: The main goals of cholesteatoma surgery remain the avoidance of recidivism and optimal hearing rehabilitation. We recommend a tailored approach in the treatment of cholesteatomas and not a dogmatic one. Surgeons should not hesitate to perform a CWD procedure if required. Performed correctly it results in a dry ear and CWD surgery should remain in the skill set of the otologic surgeon.
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Treatment of 3-(3,4-di-hydroxy-phen-yl)propenoic acid (caffeic acid or 3,4-di-hydroxy-cinnamic acid) with the alkali hydroxides MOH (M = Li, Na) in aqueous solution led to the formation of poly[aqua-[µ-3-(3,4-di-hydroxy-phen-yl)propenoato]lithium], [Li(C9H7O4)(H2O)]n, 1, and poly[aqua-[µ-3-(3,4-di-hydroxy-phen-yl)propenoato]sodium], [Na(C9H7O4)(H2O)]n, 2. The crystal structure of 1 consists of a lithium cation that is coordinated nearly tetra-hedrally by three carboxyl-ate oxygen atoms and a water mol-ecule. The carboxyl-ate groups adopt a µ3-κ3 O:O':O' coordination mode that leads to a chain-like catenation of Li cations and carboxyl-ate units parallel to the b axis. Moreover, the lithium carboxyl-ate chains are connected by hydrogen bonds between water mol-ecules attached to lithium and catechol OH groups. The crystal structure of 2 shows a sevenfold coordination of the sodium cation by one water mol-ecule, two monodentately binding carboxyl-ate groups and four oxygen atoms from two catechol groups. The coordination polyhedra are linked by face- and edge-sharing into chains extending parallel to the b axis. The chains are inter-linked by the bridging 3-(3,4-di-hydroxy-phen-yl)propenoate units and by inter-molecular hydrogen bonds to form the tri-periodic network.
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Recently, glycogen synthase kinase-3ß (GSK-3ß) has been considered as a critical factor implicated in Alzheimer's disease (AD). In a previous work, a 3D pharmacophore model for GSK-3ß inhibitors was created and the results suggested that derivative ZINC67773573, VIII, may provide a promising lead for developing novel GSK-3ß inhibitors for the AD's treatment. Consequently, in this work, novel series of quinolin-2-one derivatives were synthesized and assessed for their GSK-3ß inhibitory properties. In vitro screening identified three compounds: 7c, 7e and 7f as promising GSK-3ß inhibitors. Compounds 7c, 7e and 7f were found to exhibit superior inhibitory effect on GSK-3ß with IC50 value ranges between 4.68 ± 0.59 to 8.27 ± 0.60 nM compared to that of staurosporine (IC50 = 6.12 ± 0.74 nM). Considerably, compounds 7c, 7e and 7f effectively lowered tau hyperphosphorylated aggregates and proving their safety towards the SH-SY5Y and THLE2 normal cell lines. The most promising compound 7c alleviated cognitive impairments in the scopolamine-induced model in mice. Compound 7c's activity profile, while not highly selective, may provide a starting point and valuable insights into the design of multi-target inhibitors. According to the ADME prediction results, compounds 7c, 7e and 7f followed Lipinski's rule of five and could almost permeate through the BBB. Molecular docking simulations showed that these compounds are well accommodated in the ATP binding site interacting by its quinoline-2-one ring through hydrogen bonding with the key amino acids Asp133 and Val135 at the hinge region. The findings of this study suggested that these new compounds may have potential as anti-AD drugs targeting GSK-3ß.
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Doença de Alzheimer , Neuroblastoma , Humanos , Animais , Camundongos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Simulação de Acoplamento Molecular , Glicogênio Sintase Quinase 3 beta/metabolismo , Farmacóforo , Fosforilação , Proteínas tau/metabolismoRESUMO
Oxometalates of vanadium(V), chromium(VI), and manganese(VII) have negative impacts on water resources due to their toxicity. To remove them, the kinetics of 0.04 mM oxometalates in natural and synthetic water were studied using graphene nanoplatelets (GNP). The GNP were dispersible in water and formed aggregates >15 µm that could be easily separated. Within 30 min, the GNP were covered with ~0.4 mg/g vanadium and ~1.0 mg/g chromium as Cr(OH)3. The reaction of 0.04 mM permanganate with 50 mg of GNP resulted in a coverage of 10 mg/g in 5 min, while the maximum value was 300 mg/g manganese as Mn2O3/MnO. TEM showed a random metal distribution on the surfaces; no clusters or nanoparticles were detected. The rate of disappearance in aerated water followed a pseudo second-order adsorption kinetics (PSO) for V(V), a pseudo second-order reaction for Cr(VI), and a pseudo first-order reaction for Mn(VII). For Cr(VI) and Mn(VII), the rate constants were found to depend on the GNP mass. Oxygen sorption occurred with PSO kinetics as a parallel slow process upon contact of GNP with air-saturated water. For thermally regenerated GNP, the rate constant decreased for V(V) but increased for Cr(VI), while no effect was observed for Mn(VII). GNP capacity was enhanced through regeneration for V(V) and Cr(VI); no effect was observed for Mn(VII). The reactions are well-suited for use in water purification processes and the reaction products, GNP, decorated with single metal atoms, are of great interest for the construction of sensors, electronic devices, and for application in single-atom catalysis (SAC).
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The continuous evolution of molecular biology and gene synthesis methods paired with an ever-increasing potential of synthetic biology approaches and genome engineering toolkits enables the rapid design of genetic bioparts and genetically modified organisms. Although various software solutions assist with specific design tasks and challenges, lab internal documentation and ensuring compliance with governmental regulations on biosafety assessment of the generated organisms remain the responsibility of individual academic researchers. This results in inconsistent and redundant documentation regimes and a significant time and labor burden. GMOCU (GMO documentation) is a standardized semi-automatic user-oriented software approach -written in Python and freely available- that unifies lab internal data documentation on genetic parts and genetically modified organisms (GMOs). It automatizes biological risk evaluations and maintains a shared up-to-date inventory of bioparts for team-wide data navigation and sharing. GMOCU further enables data export into customizable formats suitable for scientific publications, official biosafety documents, and the research community.
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Documentação , Software , Medição de Risco , Regulamentação GovernamentalRESUMO
Treatment of 3-formyl-acetyl-acetone with the amines benzyl-amine, tert-butyl-amine and (S)-methyl-benzyl-amine led to the formation of the corresponding Schiff bases 3-[(benzyl-amino)-methyl-idene]pentane-2,4-dione, C13H15NO2 (1), 3-[(tert-butyl-amino)-methyl-idene]pentan-2,4-dione, C10H17NO2 (2) and 3-{[(S)-benz-yl(meth-yl)amino]-methyl-idene}pentane-2,4-dione, C14H17NO2 (3). The mol-ecules of all three compounds exist as enamine tautomers that contain a nearly planar amino-methyl-ene-pentane-2,4-dione core with a strong intra-molecular N-Hâ¯O hydrogen bridge. The R group attached to the enamine N atom has no significant influence on the bond lengths and angles of the amino-methyl-ene-pentane-2,4-dione core. The supra-molecular structures in 1-3 are mainly based on weak C-Hâ¯O hydrogen bonds.
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In this article, we propose an evolved system design approach to ultra-wideband (UWB) radar based on pseudo-random noise (PRN) sequences, the key features of which are its user-adaptability to meet the demands provided by desired microwave imaging applications and its multichannel scalability. In light of providing a fully synchronized multichannel radar imaging system for short-range imaging as mine detection, non-destructive testing (NDT) or medical imaging, the advanced system architecture is presented with a special focus put on the implemented synchronization mechanism and clocking scheme. The core of the targeted adaptivity is provided by means of hardware, such as variable clock generators and dividers as well as programmable PRN generators. In addition to adaptive hardware, the customization of signal processing is feasible within an extensive open-source framework using the Red Pitaya® data acquisition platform. A system benchmark in terms of signal-to-noise ratio (SNR), jitter, and synchronization stability is conducted to determine the achievable performance of the prototype system put into practice. Furthermore, an outlook on the planned future development and performance improvement is provided.
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BACKGROUND: There is no evidence of effectiveness for interdisciplinary second opinion procedures (ISOP) for recommended back surgery (BS). Since 2015, AOK Nordost has been offering the care program RückenSPEZIAL comprising a preliminary examination, ISOP, and optional interdisciplinary multimodal pain therapy (IMPT). The objective of this study is to determine the effectiveness of RückenSPEZIAL to reduce BS and back pain-related costs (BPRC) compared to patients who likewise received a recommendation for back surgery but not RückenSPEZIAL. METHODS: Insured persons in the AOK Nordost consulted the AOK service center, presented a BS hospital admission slip and received advice to participate in RückenSPEZIAL. Following a 1:1 "matched pairs" selection, patients who participated in RückenSPEZIAL (intervention group [IG]) after this consultation (reference date) where compared with patients who did not participate after this consultation (comparison group [CG]). Patient characteristics, BS and BPRC were operationalised from AOK Nordost claims data. RESULTS: Of 108 IG patients and 108 CG patients, 34 (42%) fewer IG patients had one or more BS in 365 following days (relative risk [RR] 0.58; pâ¯< 0.001). The subgroup analysis showed for 21 IG patients with ISOP and IMPT an RR of 0.13 (pâ¯< 0.001), and for 67 IG patients with solely ISOP without IMPT an RR of 0.59 (pâ¯< 0.001). The increase in RBC from the previous year to the following year was 50.2 percentage points lower for IG patients compared to CG patients (pâ¯= 0.088). DISCUSSION: The differences in BS were significant (pâ¯< 0.05) and in favor of RückenSPEZIAL. For the specific population it can be expected that mainly savings on BS can cover the intervention costs of RückenSPEZIAL (approximately significant, small case number). Bias due to self-selection needs to be assumed.
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Dor nas Costas , Hospitalização , Humanos , Dor nas Costas/terapia , Encaminhamento e ConsultaRESUMO
Addition of 2-aminobenzothiazole (abt) and substituted derivatives to Hg(OAc)2 leads to the high yield formation of ortho-cyano-aminothiophenolate (ocap) complexes [Hg{SC6H3XN(CîN)}]n (X = H, Me, Cl, Br, NO2) resulting from dehydrogenation and C-S bond cleavage. The reaction appears to be unique to Hg(OAc)2 and with HgCl2 the product [HgCl2(abt)]n contains an intact abt ligand, but reacts with acetate to afford the ocap complex [Hg{SC6H4N(CîN)}]n. Binding of abt to Hg(II) has previously been probed in molecular structures of [Hg(sac)2(abt)L] (L = MeOH, DMSO) and these have been reexamined to understand the perturbation of abt upon coordination. When the reaction of abt and Hg(OAc)2 was carried out at low temperatures the intermediate [Hg(κ2-OAc)(EtOH)(µ-HNCNSC6H4)]2 was isolated resulting from a single ligand deprotonation thus allowing a mechanism for ring-opening to be proposed. Reactions of [Hg{SC6H3XN(CîN)}]n with mono- and bidentate phosphines have been studied, affording a series of complexes in which the ocap ligands adopt four different binding modes in the solid state, as shown by a number of crystallographic studies. In all, the ligand chelates to a single mercury centre but spans to the second via either: (i) a simple S,N-chelate, (ii) coordination through nitrogen of the CîN group, (iii) the sulfur acting as a thiolate-bridge, (iv) both thiolate bridging and cyanide coordination. With PPh3 two different binding modes are seen in complexes [Hg{SC6H3XN(CîN)}(PPh3)]2 being dependant upon the nature of the arene-substituent, while addition of excess PPh3 affords mononuclear [Hg{SC6H3XN(CîN)}(PPh3)2]. With dppm, binuclear [Hg{SC6H3XN(CîN)}(κ1-dppm)]2 result in which the diphosphine binds in a monodentate fashion. With the more flexible diphosphines, dppe and dppb, coordination polymers [Hg{SC6H3XN(CîN)}(κ1,κ1-diphosphine)]n result in which ocap binds in a simple chelate fashion. Somewhat unexpectedly, with dppp, binuclear complexes [Hg2{SC6H3XN(CîN)}2(µ,κ1,κ1-dppp)] result in which two diphosphines bridge the Hg2 centre, while with dppf mononuclear chelates are proposed to result. Thus, the simple and high-yielding ring-opening of 2-aminobenzothiazole and substituted derivatives by mercuric acetate provides ready access to a range of novel ortho-cyano-aminothiophenolate complexes, being shown to be a highly versatile ligand that can adopt a number of different coordination modes.
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Recovering speech in the absence of the acoustic speech signal itself, i.e., silent speech, holds great potential for restoring or enhancing oral communication in those who lost it. Radar is a relatively unexplored silent speech sensing modality, even though it has the advantage of being fully non-invasive. We therefore built a custom stepped frequency continuous wave radar hardware to measure the changes in the transmission spectra during speech between three antennas, located on both cheeks and the chin with a measurement update rate of 100 Hz. We then recorded a command word corpus of 40 phonetically balanced, two-syllable German words and the German digits zero to nine for two individual speakers and evaluated both the speaker-dependent multi-session and inter-session recognition accuracies on this 50-word corpus using a bidirectional long-short term memory network. We obtained recognition accuracies of 99.17% and 88.87% for the speaker-dependent multi-session and inter-session accuracy, respectively. These results show that the transmission spectra are very well suited to discriminate individual words from one another, even across different sessions, which is one of the key challenges for fully non-invasive silent speech interfaces.
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Percepção da Fala , Fala , Idioma , Radar , Reconhecimento PsicológicoRESUMO
Treatment of 3-formyl-acetyl-acetone with the isomeric o-, m- and p-amino-benzoic acids led to the formation of the corresponding Schiff bases, namely, 3-[(2-carb-oxy-phenyl-amino)-methyl-idene]pentane-2,4-dione, 1, 3-[(3-carb-oxy-phenyl-amino)-methyl-idene]pentane-2,4-dione, 2, and 3-[(4-carb-oxy-phenyl-amino)-methyl-idene]pentane-2,4-dione, 3, all C13H13NO4, that contain a planar amino-methyl-ene-pentane-2,4-dione core with a strong intra-molecular N-Hâ¯O hydrogen bridge. The carb-oxy-phenyl groups attached to the nitro-gen atom are almost coplanar to the central mol-ecular fragment. Depending on the position of the carboxyl unit, different supra-molecular structures with hydrogen-bonding networks are formed in the three title structures.
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BACKGROUND: Noninvasive remote patient management (RPM) in patients with heart failure (HF) has been shown to reduce the days lost due to unplanned cardiovascular hospital admissions and all-cause mortality in the Telemedical Interventional Management in Heart Failure II trial (TIM-HF2). The health economic implications of these findings are the focus of the present analyses from the payer perspective. METHODS AND RESULTS: A total of 1538 participants of the TIM-HF2 randomized controlled trial were assigned to the RPM and Usual Care group. Health claims data were available for 1450 patients (n = 715 RPM group, n = 735 Usual Care group), which represents 94.3% of the original TIM-HF2 patient population, were linked to primary data from the study documentation and evaluated in terms of the health care cost, total cost (accounting for intervention costs), costs per day alive and out of hospital (DAOH), and cost per quality-adjusted life year (QALY). The average health care costs per patient year amounted to 14,412 (95% CI 13,284-15,539) in the RPM group and 17,537 (95% CI 16,179-18,894) in the UC group. RPM led to cost savings of 3125 per patient year (p = 0.001). After including the intervention costs, a cost saving of 1758 per patient year remained (p = 0.048). CONCLUSION: The additional noninvasive telemedical interventional management in patients with HF was cost-effective compared to standard care alone, since such intervention was associated with overall cost savings and superior clinical effectiveness.
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Insuficiência Cardíaca , Telemedicina , Humanos , Análise Custo-Benefício , Insuficiência Cardíaca/terapia , Telemedicina/métodos , Hospitalização , Custos de Cuidados de Saúde , Anos de Vida Ajustados por Qualidade de VidaRESUMO
8-Nitrobenzothiazinones (BTZs) are a promising class of antimycobacterial agents currently under investigation in clinical trials. Starting from thiourea derivatives, a new synthetic pathway to BTZs was established. It allows the formation of the thiazinone ring system in one synthetic step and is applicable for preparation of a wide variety of BTZ analogues. The synthetic procedure furthermore facilitates the replacement of the sulphur atom in the thiazinone ring system by oxygen or nitrogen to afford the analogous benzoxazinone and quinazolinone systems. 36 BTZ analogues were prepared and tested in luminescence-based assays for inâ vitro activity against Mycobacterium tuberculosis (Mtb) using the microdilution broth method and a high-throughput macrophage infection assay.
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Mycobacterium tuberculosis , Antituberculosos/metabolismo , Antituberculosos/farmacologia , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/metabolismoRESUMO
OBJECTIVE: Stroke survivors commonly suffer from dysphagia, originating from oro-facial impairments which affect swallowing function. Functional therapy often employs tongue exercises that require the patient to perform short motion sequences. Evaluating the patient's performance on those exercises is difficult, because there is no reliable form of visual feedback. METHODS: We propose an optopalatographic device that does not require a personalized dental retainer and is capable of measuring tongue movement trajectories intraorally. The device features nine optical proximity sensors at 100 Hz and is fixated against the hard palate with a specifically developed palatal adhesive. The sensing capabilities of the device were evaluated on a tongue gesture corpus recorded from nine healthy individuals, containing eight different tongue exercises commonly used in functional dysphagia therapy. RESULTS: The measured tongue trajectories contained temporally and spatially resolved information about the tongue movement and location during each exercise. Furthermore, a simple DTW-kNN classifier was able to distinguish the exercises from one another with an average classification accuracy of 97.9 % and 61.4 % (cross-validation and inter-speaker test accuracy, respectively). CONCLUSION: the device can provide real-time feedback for tongue motion and we obtained promising gesture recognition results with relatively few sensors, even in the absence of a personalized dental retainer. SIGNIFICANCE: Non-personalized optopalatography is readily available and could aid in improving functional dysphagia therapy by providing visual feedback to both the physician and patient.
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Transtornos de Deglutição , Deglutição , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/terapia , Humanos , Pressão , Estudos Prospectivos , LínguaRESUMO
Introduction Chronic otitis media (COM) with a central perforation or a concomitant cholesteatoma are both inflammatory lesions, however, with different etiologies. Both entities may present with an intact chain, and the final reconstruction is quite similar. Does it also apply for the hearing outcome? Objectives In a retrospective analysis, we investigated the preoperative hearing and the final hearing outcome of two groups of patients: those with COM and those with cholesteatoma, and compared various factors. Methods Patients operated between 2010 and 2019 were entered prospectively into a research database, and the integrity of the ossicular chain, the extent of the cholesteatoma, and the findings on computed tomography (CT) scans were retrospectively analyzed and correlated to the final hearing outcome. Results Out of 210 tympanoplasties for COM, 162 (80%) presented with an intact chain, and 85 (40%) ears could be analyzed. Out of 283 cholesteatoma surgeries, 53 (19%) ears presented with an intact chain. The preoperative air-bone gap (ABG) was worse in the COM group, but the postoperative ABG over the frequencies of 0.5 kHz and 4 kHz was the same (10 dB to 12 dB) in both groups, and remained within 20 dB in 90% (40 and 78 patients, respectively). The extension of the disease was rather limited in the cholesteatoma group (stages Ch1a and 1b), and better pneumatization and ventilation were beneficial for a good result. Postoperatively, the frequency of 4 kHz had the largest ABG (14 dB and 18 dB). Conclusion Overall, 80% of the patients with COM and less than 20% of those with cholesteatoma had an intact and mobile chain at surgery. Using equivalent surgical techniques for the tympanoplasty, the final outcome was almost the same for both groups, with a mean ABG of 10 dB to 12 dB.
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In ultrasound nondestructive testing (NDT), a widespread approach is to take synthetic aperture measurements from the surface of a specimen to detect and locate defects within it. Based on these measurements, imaging is usually performed using the synthetic aperture focusing technique (SAFT). However, SAFT is suboptimal in terms of resolution and requires oversampling in the time domain to obtain a fine grid for the delay-and-sum (DAS). On the other hand, parametric reconstruction algorithms give better resolution, but their usage for imaging becomes computationally expensive due to the size of the parameter space and a large amount of measurement data in realistic 3-D scenarios when using oversampling. In the literature, the remedies to this are twofold. First, the amount of measurement data can be reduced using state-of-the-art sub-Nyquist sampling approaches to measure Fourier coefficients instead of time-domain samples. Second, parametric reconstruction algorithms mostly rely on matrix-vector operations that can be implemented efficiently by exploiting the underlying structure of the model. In this article, we propose and compare different strategies to choose the Fourier coefficients to be measured. Their asymptotic performance is compared by numerically evaluating the Cramér-Rao bound (CRB) for the localizability of the defect coordinates. These subsampling strategies are then combined with an l1 -minimization scheme to compute 3-D reconstructions from the low-rate measurements. Compared to conventional DAS, this allows us to formulate a fully physically motivated forward model matrix. To enable this, the projection operations of the forward model matrix are implemented matrix-free by exploiting the underlying two-level Toeplitz structure. Finally, we show that high-resolution reconstructions from as low as a single Fourier coefficient per A-scan are possible based on simulated data and measurements from a steel specimen.
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Algoritmos , Análise de Fourier , UltrassonografiaRESUMO
Abstract Introduction Chronic otitis media (COM) with a central perforation or a concomitant cholesteatoma are both inflammatory lesions, however, with different etiologies. Both entities may present with an intact chain, and the final reconstruction is quite similar. Does it also apply for the hearing outcome? Objectives In a retrospective analysis, we investigated the preoperative hearing and the final hearing outcome of two groups of patients: those with COM and those with cholesteatoma, and compared various factors. Methods Patients operated between 2010 and 2019 were entered prospectively into a research database, and the integrity of the ossicular chain, the extent of the cholesteatoma, and the findings on computed tomography (CT) scans were retrospectively analyzed and correlated to the final hearing outcome. Results Out of 210 tympanoplasties for COM, 162 (80%) presented with an intact chain, and 85 (40%) ears could be analyzed. Out of 283 cholesteatoma surgeries, 53 (19%) ears presented with an intact chain. The preoperative air-bone gap (ABG) was worse in the COM group, but the postoperative ABG over the frequencies of 0.5 kHz and 4 kHz was the same (10 dB to 12 dB) in both groups, and remained within 20 dB in 90% (40 and 78 patients, respectively). The extension of the disease was rather limited in the cholesteatoma group (stages Ch1a and 1b), and better pneumatization and ventilation were beneficial for a good result. Postoperatively, the frequency of 4 kHz had the largest ABG (14 dB and 18 dB). Conclusion Overall, 80% of the patients with COM and less than 20% of those with cholesteatoma had an intact and mobile chain at surgery. Using equivalent surgical techniques for the tympanoplasty, the final outcome was almost the same for both groups, with a mean ABG of 10 dB to 12 dB.
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Vacuolar myelinopathy is a fatal neurological disease that was initially discovered during a mysterious mass mortality of bald eagles in Arkansas in the United States. The cause of this wildlife disease has eluded scientists for decades while its occurrence has continued to spread throughout freshwater reservoirs in the southeastern United States. Recent studies have demonstrated that vacuolar myelinopathy is induced by consumption of the epiphytic cyanobacterial species Aetokthonos hydrillicola growing on aquatic vegetation, primarily the invasive Hydrilla verticillata Here, we describe the identification, biosynthetic gene cluster, and biological activity of aetokthonotoxin, a pentabrominated biindole alkaloid that is produced by the cyanobacterium A. hydrillicola We identify this cyanobacterial neurotoxin as the causal agent of vacuolar myelinopathy and discuss environmental factors-especially bromide availability-that promote toxin production.
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Toxinas Bacterianas/toxicidade , Cianobactérias , Doenças Desmielinizantes/veterinária , Águias , Alcaloides Indólicos/toxicidade , Neurotoxinas/toxicidade , Animais , Toxinas Bacterianas/biossíntese , Toxinas Bacterianas/química , Toxinas Bacterianas/isolamento & purificação , Doenças das Aves/induzido quimicamente , Brometos/metabolismo , Bromo/análise , Caenorhabditis elegans/efeitos dos fármacos , Galinhas , Cianobactérias/genética , Cianobactérias/crescimento & desenvolvimento , Cianobactérias/metabolismo , Doenças Desmielinizantes/induzido quimicamente , Genes Bacterianos , Hydrocharitaceae/metabolismo , Hydrocharitaceae/microbiologia , Alcaloides Indólicos/química , Alcaloides Indólicos/isolamento & purificação , Dose Letal Mediana , Família Multigênica , Neurotoxinas/biossíntese , Neurotoxinas/química , Neurotoxinas/isolamento & purificação , Sudeste dos Estados Unidos , Triptofano/metabolismo , Peixe-ZebraRESUMO
In response to increasingly stringent restrictions for drinking water quality, a parallel operation of two common technologies, low-pressure reverse osmosis (LPRO) and activated carbon filtration (ACF), was investigated in a comprehensive five-month pilot study for the removal of 32 typical trace organic contaminants (TrOCs) from Rhine bank filtrates employing a semi- technical plant. TrOCs have been divided into three groups: polyfluorinated aliphatic compounds; pharmaceuticals, pesticides and metabolites; in addition to volatiles, nitrosamines and aminopolycarboxylic acids, which were also examined. The net pressure behavior, normalized salt passage and rejection of TrOCs by LPRO were investigated and compared with ACF operation. In addition, autopsies from the leading and last membrane modules were performed using adenosine triphosphate (ATP), total organic carbon (TOC), ICP-OES and SEM-EDX techniques. Generally, rather stable LPRO membrane performance with limited membrane fouling was observed. TrOCs with a molecular weight of ≥ 150 Da were completely retained by LPRO, while the rejection of di- and trichloro compounds improved as the filtration progressed. ACF also showed significant removal for most of the TrOCs, but without desalination. Accordingly, the ACF and LPRO can be operated in parallel such that the LPRO permeate and the ACF-treated bypass can be mixed to produce drinking water with adjustable hardness and significantly reduced TrOCs.
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The complexes bis-(acetyl-acetonato-κ2 O,O')(N,N,N',N'-tetra-methyl-ethylenedi-amine-κ2 N,N')manganese(II), [Mn(C5H7O2)2(C6H16N2)], bis-(acetyl-acetonato-κ2 O,O')(N,N,N',N'-tetra-methyl-ethylenedi-amine-κ2 N,N')iron(II), [Fe(C5H7O2)2(C6H16N2)], and bis-(acetyl-acetonato-κ2 O,O')(N,N,N',N'-tetra-methyl-ethylenedi-amine-κ2 N,N')zinc(II), [Zn(C5H7O2)2(C6H16N2)], were synthesized from the reaction of the corresponding metal acetyl-acetonates [M(acac)2(H2O)2] with N,N,N',N'-tetra-methyl-ethylenedi-amine (TMEDA) in toluene. Each of the complexes displays a central metal atom which is nearly octa-hedrally surrounded by two chelating acac and one chelating TMEDA ligand, resulting in an N2O4 coordination set. Despite the chemical similarity of the complex units, the packing patterns for compounds 1-3 are different and thus the crystal structures are not isotypic.