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1.
Artigo em Inglês | MEDLINE | ID: mdl-39244147

RESUMO

BACKGROUND: To date, long-term results of the arthroscopic repair of glenoid rim fractures are missing. The aim of this study was, to evaluate clinical and radiographic results following arthroscopic repair of anteroinferior glenoid fractures using anchors or bioabsorbable compression screws after a mean follow-up period of ten years. METHODS: Clinical outcome measures included evaluation of recurrent instability, the Constant Score (CS), Subjective Shoulder Value (SSV), Rowe Score (RS), Western Ontario Shoulder Instability Score (WOSI) and Melbourne Instability Shoulder Score (MISS). X-ray images were obtained for assessment of an instability arthropathy (IA). RESULTS: 23 patients (7 female and 16 male, mean (± SD) age 48 ± 15 years) who underwent arthroscopic repair of an acute substantial solitary or multifragmented anteroinferior glenoid rim fracture were enrolled. After a mean follow-up period of 10 ± 2 years, patients reached a mean CS of 92 ± 10 points, SSV of 93 ± 11%, RS of 84 ± 20 points, WOSI of 98 ±2% and MISS of 91 ± 11 points. No patient suffered recurrent dislocation. Radiographic results were obtained of 18 patients. Signs of IA were noted in nine patients (50%) with progression of IA in all cases in comparison to the preoperative status. Patients with IA were significantly older (52 versus 38 years, p = 0.04). Clinical score results did not show a significant difference in patients with versus without IA except for the RS (74 versus 94 points, p = 0.02). No intra- or postoperative complications were observed, and no patient required revision endoprosthetic surgery. CONCLUSION: Arthroscopic repair of acute anteroinferior glenoid rim fractures shows good clinical long-term results. High rates of IA were observed especially in older patients. However, the presence of IA did not seem to influence the subjective shoulder score outcomes.

2.
Audiol Res ; 13(5): 753-766, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37887848

RESUMO

Electric stimulation via a cochlear implant (CI) enables people with severe-to-profound sensorineural hearing loss to regain speech understanding and music appreciation and, thus, allow them to actively engage in social life. Three main manufacturers (CochlearTM, MED-ELTM, and Advanced BionicsTM "AB") have been offering CI systems, thus challenging CI recipients and otolaryngologists with a difficult decision as currently no comprehensive overview or meta-analysis on performance outcomes following CI implantation is available. The main goals of this scoping review were to (1) map the literature on speech and music performance outcomes and to (2) find whether studies have performed outcome comparisons between devices of different manufacturers. To this end, a literature search was conducted to find studies that address speech and music outcomes in CI recipients. From a total of 1592 papers, 188 paper abstracts were analyzed and 147 articles were found suitable for an examination of full text. From these, 42 studies were included for synthesis. A total of 16 studies used the consonant-nucleus-consonant (CNC) word recognition test in quiet at 60 db SPL. We found that aside from technical comparisons, very few publications compared speech outcomes across manufacturers of CI systems. However, evidence suggests that these data are available in large CI centers in Germany and the US. Future studies should therefore leverage large data cohorts to perform such comparisons, which could provide critical evaluation criteria and assist both CI recipients and otolaryngologists to make informed performance-based decisions.

3.
J Integr Bioinform ; 19(4)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36054833

RESUMO

The implementation of Artificial Intelligence (AI) still faces significant hurdles and one key factor is the access to data. One approach that could support that is federated machine learning (FL) since it allows for privacy preserving data access. For this proof of concept, a prediction model for coronary artery calcification scores (CACS) has been applied. The FL was trained based on the data in the different institutions, while the centralized machine learning model was trained on one allocation of data. Both algorithms predict patients with risk scores ≥5 based on age, biological sex, waist circumference, dyslipidemia and HbA1c. The centralized model yields a sensitivity of c. 66% and a specificity of c. 70%. The FL slightly outperforms that with a sensitivity of 67% while slightly underperforming it with a specificity of 69%. It could be demonstrated that CACS prediction is feasible via both, a centralized and an FL approach, and that both show very comparable accuracy. In order to increase accuracy, additional and a higher volume of patient data is required and for that FL is utterly necessary. The developed "CACulator" serves as proof of concept, is available as research tool and shall support future research to facilitate AI implementation.


Assuntos
Inteligência Artificial , Vasos Coronários , Humanos , Estudo de Prova de Conceito , Aprendizado de Máquina , Atenção à Saúde
4.
J Biomed Mater Res B Appl Biomater ; 110(11): 2494-2505, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35678249

RESUMO

For cochlear implants (CI) a final position of the electrode array (EA) along the inner wall of the spirally shaped cochlea is considered to be beneficial because it results in a closer proximity to the auditory nerve fibers. A shape memory effect (SME) could facilitate such shift of the EA toward the cochlear inner wall, but its implementation remains to be solved. The current study presents an EA prototype featuring the SME with minute adjustments of the material properties of Nitinol, a shape memory alloy, in combination with a suitable cooling strategy to prevent premature curling. Ten samples were successfully inserted by a CI surgeon into an artificial cochlear model submerged into a temperature-controllable water bath to simulate temporary hypothermia of the inner ear (31°C). Gentle insertions were possible, with an average insertion speed of 0.81 ± 0.14 mm/s. After recovery of body temperature, the desired position shift toward the modiolus was observed in all trials. Angular insertion depth increased by approximately 81.8° ± 23.4°. We demonstrate for the first time that using the body temperature responsive SME for perimodiolar EA positioning is feasible and does not impede a gentle surgical insertion.


Assuntos
Implante Coclear , Implantes Cocleares , Cóclea/cirurgia , Implante Coclear/métodos , Eletrodos Implantados , Ligas de Memória da Forma , Água
5.
Front Digit Health ; 3: 594971, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34713083

RESUMO

Background: Artificial Intelligence (AI) in healthcare has demonstrated high efficiency in academic research, while only few, and predominantly small, real-world AI applications exist in the preventive, diagnostic and therapeutic contexts. Our identification and analysis of success factors for the implementation of AI aims to close the gap between recent years' significant academic AI advancements and the comparably low level of practical application in healthcare. Methods: A literature and real life cases analysis was conducted in Scopus and OpacPlus as well as the Google advanced search database. The according search queries have been defined based on success factor categories for AI implementation derived from a prior World Health Organization survey about barriers of adoption of Big Data within 125 countries. The eligible publications and real life cases were identified through a catalog of in- and exclusion criteria focused on concrete AI application cases. These were then analyzed to deduct and discuss success factors that facilitate or inhibit a broad-scale implementation of AI in healthcare. Results: The analysis revealed three categories of success factors, namely (1) policy setting, (2) technological implementation, and (3) medical and economic impact measurement. For each of them a set of recommendations has been deducted: First, a risk adjusted policy frame is required that distinguishes between precautionary and permissionless principles, and differentiates among accountability, liability, and culpability. Second, a "privacy by design" centered technology infrastructure shall be applied that enables practical and legally compliant data access. Third, the medical and economic impact need to be quantified, e.g., through the measurement of quality-adjusted life years while applying the CHEERS and PRISMA reporting criteria. Conclusions: Private and public institutions can already today leverage AI implementation based on the identified results and thus drive the translation from scientific development to real world application. Additional success factors could include trust-building measures, data categorization guidelines, and risk level assessments and as the success factors are interlinked, future research should elaborate on their optimal interaction to utilize the full potential of AI in real world application.

6.
J Med Internet Res ; 22(2): e16866, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-32130134

RESUMO

BACKGROUND: Positive economic impact is a key decision factor in making the case for or against investing in an artificial intelligence (AI) solution in the health care industry. It is most relevant for the care provider and insurer as well as for the pharmaceutical and medical technology sectors. Although the broad economic impact of digital health solutions in general has been assessed many times in literature and the benefit for patients and society has also been analyzed, the specific economic impact of AI in health care has been addressed only sporadically. OBJECTIVE: This study aimed to systematically review and summarize the cost-effectiveness studies dedicated to AI in health care and to assess whether they meet the established quality criteria. METHODS: In a first step, the quality criteria for economic impact studies were defined based on the established and adapted criteria schemes for cost impact assessments. In a second step, a systematic literature review based on qualitative and quantitative inclusion and exclusion criteria was conducted to identify relevant publications for an in-depth analysis of the economic impact assessment. In a final step, the quality of the identified economic impact studies was evaluated based on the defined quality criteria for cost-effectiveness studies. RESULTS: Very few publications have thoroughly addressed the economic impact assessment, and the economic assessment quality of the reviewed publications on AI shows severe methodological deficits. Only 6 out of 66 publications could be included in the second step of the analysis based on the inclusion criteria. Out of these 6 studies, none comprised a methodologically complete cost impact analysis. There are two areas for improvement in future studies. First, the initial investment and operational costs for the AI infrastructure and service need to be included. Second, alternatives to achieve similar impact must be evaluated to provide a comprehensive comparison. CONCLUSIONS: This systematic literature analysis proved that the existing impact assessments show methodological deficits and that upcoming evaluations require more comprehensive economic analyses to enable economic decisions for or against implementing AI technology in health care.


Assuntos
Inteligência Artificial/economia , Custos de Cuidados de Saúde/normas , Análise Custo-Benefício , Humanos
7.
Aquat Toxicol ; 185: 1-10, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28142078

RESUMO

In order to identify the upper limits of the molecular size of chemicals to cross the chorion of zebrafish, Danio rerio, differently sized, non-toxic and chemically inert polyethylene glycols (PEGs; 2000-12,000Da) were applied at concentrations (9.76mM) high enough to provoke osmotic pressure. Whereas small PEGs were expected to be able to cross the chorion, restricted uptake of large PEGs was hypothesized to result in shrinkage of the chorion. Due to a slow, but gradual uptake of PEGs over time, molecular size-dependent equilibration in conjunction with a regain of the spherical chorion shape was observed. Thus, the size of molecules able to cross the chorion could be narrowed down precisely to ≤4000Da, and the time-dependency of the movement across the chorion could be described. To account for associated alterations in embryonic development, fish embryo toxicity tests (FETs) according to OECD test guideline 236 (OECD, 2013) were performed with special emphasis to changes in chorion shape. FETs revealed clear-cut size-effects: the higher the actual molecular weight (=size) of the PEG, the more effects (both acutely toxic and sublethal) were found. No effects were seen with PEGs of 2000 and 3000Da. In contrast, PEG 8000 and PEG 12,000 were found to be most toxic with LC50 values of 16.05 and 16.40g/L, respectively. Likewise, the extent of chorion shrinkage due to increased osmotic pressure strictly depended on PEG molecular weight and duration of exposure. A reflux of water and PEG molecules into the chorion and a resulting re-shaping of the chorion could only be observed for eggs exposed to PEGs ≤4000Da. Results clearly indicate a barrier function of the zebrafish chorion for molecules larger than 3000 to 4,000Da.


Assuntos
Córion/metabolismo , Embrião não Mamífero/metabolismo , Testes de Toxicidade Aguda , Poluentes Químicos da Água/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo , Animais , Córion/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Peso Molecular , Osmose/efeitos dos fármacos , Óvulo/efeitos dos fármacos , Polietilenoglicóis/toxicidade , Fatores de Tempo
8.
Microbiology (Reading) ; 152(Pt 7): 1929-1940, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16804169

RESUMO

Sphingomonas xenophaga BN6 degrades various (substituted) naphthalenesulfonates to the corresponding (substituted) salicylates. A gene cluster was identified on the plasmid pBN6 which coded for several enzymes participating in the degradative pathway for naphthalenesulfonates. A DNA fragment of 16 915 bp was sequenced which contained 17 ORFs. The genes encoding the 1,2-dihydroxynaphthalene dioxygenase, 2-hydroxychromene-2-carboxylate isomerase, and 2'-hydroxybenzalpyruvate aldolase of the naphthalenesulfonate pathway were identified on the DNA fragment and the encoded proteins heterologously expressed in Escherichia coli. Also, the genes encoding the ferredoxin and ferredoxin reductase of a multi-component, ring-hydroxylating naphthalenesulfonate dioxygenase were identified by insertional inactivation. The identified genes generally demonstrated the highest degree of homology to enzymes encoded by the phenanthrene-degrading organism Sphingomonas sp. P2, or the megaplasmid pNL1 of the naphthalene- and biphenyl-degrading strain Sphingomonas aromaticivorans F199. The genes of S. xenophaga BN6 participating in the degradation of naphthalenesulfonates also shared the same organization in three different transcriptional units as the genes involved in the degradation of naphthalene, biphenyl, and phenanthrene previously found in Sphingomonas sp. P2 and S. aromaticivorans F199. The genes were flanked in S. xenophaga BN6 by ORFs which specify proteins that show the highest homologies to proteins of mobile genetic elements.


Assuntos
Genes Bacterianos , Naftalenossulfonatos/metabolismo , Sphingomonas/genética , Sequência de Bases , Dados de Sequência Molecular , Fases de Leitura Aberta , Sphingomonas/metabolismo
9.
J Bacteriol ; 186(12): 3862-72, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15175300

RESUMO

A systematic survey for the presence of plasmids in 17 different xenobiotic-degrading Sphingomonas strains was performed. In almost all analyzed strains, two to five plasmids with sizes of about 50 to 500 kb were detected by using pulsed-field gel electrophoresis. A comparison of plasmid preparations untreated or treated with S1 nuclease suggested that, in general, Sphingomonas plasmids are circular. Hybridization experiments with labeled gene probes suggested that large plasmids are involved in the degradation of dibenzo-p-dioxin, dibenzofuran, and naphthalenesulfonates in S. wittichii RW1, Sphingomonas sp. HH69, and S. xenophaga BN6, respectively. The plasmids which are responsible for the degradation of naphthalene, biphenyl, and toluene by S. aromaticivorans F199 (pNL1) and of naphthalenesulfonates by S. xenophaga BN6 (pBN6) were site-specifically labeled with a kanamycin resistance cassette. The conjugative transfer of these labeled plasmids was attempted with various bacterial strains as putative recipient strains. Thus, a conjugative transfer of plasmid pBN6 from S. xenophaga BN6 to a cured mutant of strain BN6 and to Sphingomonas sp. SS3 was observed. The conjugation experiments with plasmid pNL1 suggested a broader host range of this plasmid, because it was transferred without any obvious structural changes to S. yanoikuyae B1, Sphingomonas sp. SS3, and S. herbicidovorans. In contrast, major plasmid rearrangements were observed in the transconjugants after the transfer of plasmid pNL1 to Sphingomonas sp. HH69 and of pBN6 to Sphingomonas sp. SS3. No indications for the transfer of a Sphingomonas plasmid to bacteria outside of the Sphingomonadaceae were obtained.


Assuntos
Conjugação Genética , Plasmídeos/genética , Sphingomonas/genética , Xenobióticos/metabolismo , Biodegradação Ambiental , DNA Bacteriano/genética , Dioxinas/metabolismo , Transferência Genética Horizontal , Naftalenossulfonatos/metabolismo , Sphingomonas/metabolismo
10.
J Am Coll Cardiol ; 40(6): 1067-74; discussion 1075-8, 2002 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-12354429

RESUMO

OBJECTIVE: The purpose of this study was to validate electromechanical viability parameters with combined myocardial perfusion and metabolic imaging and echocardiography. BACKGROUND: The NOGA System is a catheter-based, non-fluoroscopic, three-dimensional endocardial mapping system. This unique technique allows accurate simultaneous assessment of both local electrical activity and regional contractility. METHODS: The results of NOGA, myocardial single-photon emission computed tomography (SPECT), positron emission tomography, and echocardiography in 51 patients with coronary artery disease and a pathologic SPECT study were transcribed in a nine-segment bull's-eye projection and compared. The local shortening of normally contracting segments, as shown by echocardiography, was 9.2 +/- 5.1%, which decreased to 6.6 +/- 5.0% and 4.1 +/- 5.2% in hypokinetic and akinetic segments. The highest unipolar voltage (11.2 +/- 5.0 mV) and local shortening (8.2 +/- 5.0%) characterized normally perfused segments. Fixed perfusion defects with normal or limited 18-fluoro-2-deoxy-D-glucose uptake indicating viability had a significantly higher unipolar voltage than did scar tissue (7.25 +/- 2.7 vs. 5.0 +/- 3.1 mV, p = 0.029). CONCLUSION: Electromechanical parameters sufficiently defined the viability state of the myocardium and showed good concordance with the findings by nuclear perfusion and metabolism imaging and echocardiography. The NOGA technique provides all the relevant information immediately after coronary angiography and enables the physician to proceed with therapy in the same setting.


Assuntos
Sobrevivência Celular/fisiologia , Doença da Artéria Coronariana/diagnóstico por imagem , Ecocardiografia , Contração Miocárdica/fisiologia , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada de Emissão , Idoso , Doença da Artéria Coronariana/fisiopatologia , Eletromiografia , Feminino , Coração/diagnóstico por imagem , Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
11.
Appl Environ Microbiol ; 68(9): 4341-9, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12200285

RESUMO

During aerobic degradation of naphthalene-2-sulfonate (2NS), Sphingomonas xenophaga strain BN6 produces redox mediators which significantly increase the ability of the strain to reduce azo dyes under anaerobic conditions. It was previously suggested that 1,2-dihydroxynaphthalene (1,2-DHN), which is an intermediate in the degradative pathway of 2NS, is the precursor of these redox mediators. In order to analyze the importance of the formation of 1,2-DHN, the dihydroxynaphthalene dioxygenase gene (nsaC) was disrupted by gene replacement. The resulting strain, strain AKE1, did not degrade 2NS to salicylate. After aerobic preincubation with 2NS, strain AKE1 exhibited much higher reduction capacities for azo dyes under anaerobic conditions than the wild-type strain exhibited. Several compounds were present in the culture supernatants which enhanced the ability of S. xenophaga BN6 to reduce azo dyes under anaerobic conditions. Two major redox mediators were purified from the culture supernatants, and they were identified by high-performance liquid chromatography-mass spectrometry and comparison with chemically synthesized standards as 4-amino-1,2-naphthoquinone and 4-ethanolamino-1,2-naphthoquinone.


Assuntos
Proteínas de Bactérias/metabolismo , Naftalenossulfonatos/metabolismo , Sphingomonas/metabolismo , Anaerobiose , Proteínas de Bactérias/genética , Cromatografia Líquida , Espectrometria de Massas , Mutação , Oxirredução , Sphingomonas/genética
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