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1.
BMC Neurol ; 23(1): 2, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36597038

RESUMO

BACKGROUND: Although of high individual and socioeconomic relevance, a reliable prediction model for the prognosis of juvenile stroke (18-55 years) is missing. Therefore, the study presented in this protocol aims to prospectively validate the discriminatory power of a prediction score for the 3 months functional outcome after juvenile stroke or transient ischemic attack (TIA) that has been derived from an independent retrospective study using standard clinical workup data. METHODS: PREDICT-Juvenile-Stroke is a multi-centre (n = 4) prospective observational cohort study collecting standard clinical workup data and data on treatment success at 3 months after acute ischemic stroke or TIA that aims to validate a new prediction score for juvenile stroke. The prediction score has been developed upon single center retrospective analysis of 340 juvenile stroke patients. The score determines the patient's individual probability for treatment success defined by a modified Rankin Scale (mRS) 0-2 or return to pre-stroke baseline mRS 3 months after stroke or TIA. This probability will be compared to the observed clinical outcome at 3 months using the area under the receiver operating characteristic curve. The primary endpoint is to validate the clinical potential of the new prediction score for a favourable outcome 3 months after juvenile stroke or TIA. Secondary outcomes are to determine to what extent predictive factors in juvenile stroke or TIA patients differ from those in older patients and to determine the predictive accuracy of the juvenile stroke prediction score on other clinical and paraclinical endpoints. A minimum of 430 juvenile patients (< 55 years) with acute ischemic stroke or TIA, and the same number of older patients will be enrolled for the prospective validation study. DISCUSSION: The juvenile stroke prediction score has the potential to enable personalisation of counselling, provision of appropriate information regarding the prognosis and identification of patients who benefit from specific treatments. TRIAL REGISTRATION: The study has been registered at https://drks.de on March 31, 2022 ( DRKS00024407 ).


Assuntos
Ataque Isquêmico Transitório , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Adulto Jovem , Idoso , Ataque Isquêmico Transitório/diagnóstico , Ataque Isquêmico Transitório/epidemiologia , Ataque Isquêmico Transitório/complicações , AVC Isquêmico/complicações , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/complicações , Prognóstico , Valor Preditivo dos Testes , Estudos Observacionais como Assunto
2.
Mult Scler ; 28(10): 1630-1640, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35301890

RESUMO

BACKGROUND: Pregnancies have an impact on the disease course of multiple sclerosis (MS), but their relationship with MS risk is yet unclear. OBJECTIVE: To determine the relationships of pregnancies and gynecological diagnoses with MS risk. METHODS: In this retrospective case-control study, we assessed differences in gynecological International Classification of Diseases, 10th Revision (ICD-10) code recording rates between women with MS (n = 5720), Crohn's disease (n = 6280), or psoriasis (n = 40,555) and women without these autoimmune diseases (n = 26,729) in the 5 years before diagnosis. RESULTS: Twenty-eight ICD-10 codes were recorded less frequently for women with MS as compared to women without autoimmune disease, 18 of which are pregnancy-related. After adjustment for pregnancies, all codes unrelated to pregnancies were still negatively associated with MS. In a sensitivity analysis excluding women with evidence for possible demyelinating events before diagnosis, all associations were more pronounced. In comparison to women with psoriasis, most associations could be confirmed; that was not true in comparison to women with Crohn's disease. CONCLUSION: Our findings provide evidence for a possible protective effect of pregnancies on MS risk likely independent of or in addition to a previously suggested reversed causality. The negative associations of gynecological disorders with disease risk need further investigation. The associations might be shared by different autoimmune diseases.


Assuntos
Doenças Autoimunes , Doença de Crohn , Esclerose Múltipla , Psoríase , Estudos de Casos e Controles , Doença de Crohn/epidemiologia , Feminino , Humanos , Esclerose Múltipla/epidemiologia , Esclerose Múltipla/etiologia , Gravidez , Psoríase/complicações , Psoríase/epidemiologia , Estudos Retrospectivos
3.
Orthopade ; 51(1): 44-51, 2022 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-34032883

RESUMO

BACKGROUND: Periprosthetic infection (PPI) is a rare but serious complication. An elementary component of the therapy of PPI is the use of bone cement with the addition of antibiotics. For targeted therapy, manual mixing of antibiotics with industrially produced bone cement mixtures is often necessary. Possible problems resulting from manual mixing have not been described sufficiently so far. OBJECTIVES: Therefore, the aim of the present study was to describe the influence of the additional homogenisation by dry mixing of a polymer-active substance mixture on the quality of manually added cement. MATERIAL AND METHODS: In the laboratory-based study, four cement samples were prepared using different methods for manual addition and homogenisation of antibiotics (vancomycin). The reference control was Copal® G + V (Heraeus Medical GmbH, Wehrheim, Germany), to which the vancomycin (V) had already been industrially added. The samples were then examined for mechanical, microbiological and microscopic parameters. RESULTS: In the mechanical and microbiological results, no statistically significant differences were found between the manually added mixtures and the reference. After dry mixing of the polymer powder, the inner surface of the mixing cartridges used showed signs of scratching in the microscopic examination and showed indications of abrasion during mixing. CONCLUSION: The manual addition of antibiotics to industrially produced bone cement should be reserved for selected indications if the bone cement mixtures produced by industry are not sufficient.


Assuntos
Antibacterianos , Cimentos Ósseos , Alemanha , Humanos , Polimetil Metacrilato/efeitos adversos , Vancomicina
4.
Eur J Epidemiol ; 36(2): 233-241, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33492549

RESUMO

Infectious complications are the major cause of morbidity and mortality after solid organ and stem cell transplantation. To better understand host and environmental factors associated with an increased risk of infection as well as the effect of infections on function and survival of transplanted organs, we established the DZIF Transplant Cohort, a multicentre prospective cohort study within the organizational structure of the German Center for Infection Research. At time of transplantation, heart-, kidney-, lung-, liver-, pancreas- and hematopoetic stem cell- transplanted patients are enrolled into the study. Follow-up visits are scheduled at 3, 6, 9, 12 months after transplantation, and annually thereafter; extracurricular visits are conducted in case of infectious complications. Comprehensive standard operating procedures, web-based data collection and monitoring tools as well as a state of the art biobanking concept for blood, purified PBMCs, urine, and faeces samples ensure high quality of data and biosample collection. By collecting detailed information on immunosuppressive medication, infectious complications, type of infectious agent and therapy, as well as by providing corresponding biosamples, the cohort will establish the foundation for a broad spectrum of studies in the field of infectious diseases and transplant medicine. By January 2020, baseline data and biosamples of about 1400 patients have been collected. We plan to recruit 3500 patients by 2023, and continue follow-up visits and the documentation of infectious events at least until 2025. Information about the DZIF Transplant Cohort is available at https://www.dzif.de/en/working-group/transplant-cohort .


Assuntos
Bancos de Espécimes Biológicos , Terapia de Imunossupressão , Transplante de Órgãos , Complicações Pós-Operatórias , Projetos de Pesquisa , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Bacterianas , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
J Med Internet Res ; 23(6): e27348, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-33999836

RESUMO

BACKGROUND: Overcoming the COVID-19 crisis requires new ideas and strategies for online communication of personal medical information and patient empowerment. Rapid testing of a large number of subjects is essential for monitoring and delaying the spread of SARS-CoV-2 in order to mitigate the pandemic's consequences. People who do not know that they are infected may not stay in quarantine and, thus, risk infecting others. Unfortunately, the massive number of COVID-19 tests performed is challenging for both laboratories and the units that conduct throat swabs and communicate the results. OBJECTIVE: The goal of this study was to reduce the communication burden for health care professionals. We developed a secure and easy-to-use tracking system to report COVID-19 test results online that is simple to understand for the tested subjects as soon as these results become available. Instead of personal calls, the system updates the status and the results of the tests automatically. This aims to reduce the delay when informing testees about their results and, consequently, to slow down the virus spread. METHODS: The application in this study draws on an existing tracking tool. With this open-source and browser-based online tracking system, we aim to minimize the time required to inform the tested person and the testing units (eg, hospitals or the public health care system). The system can be integrated into the clinical workflow with very modest effort and avoids excessive load to telephone hotlines. RESULTS: The test statuses and results are published on a secured webpage, enabling regular status checks by patients; status checks are performed without the use of smartphones, which has some importance, as smartphone usage diminishes with age. Stress tests and statistics show the performance of our software. CTest is currently running at two university hospitals in Germany-University Hospital Ulm and University Hospital Tübingen-with thousands of tests being performed each week. Results show a mean number of 10 (SD 2.8) views per testee. CONCLUSIONS: CTest runs independently of existing infrastructures, aims at straightforward integration, and aims for the safe transmission of information. The system is easy to use for testees. QR (Quick Response) code links allow for quick access to the test results. The mean number of views per entry indicates a reduced amount of time for both health care professionals and testees. The system is quite generic and can be extended and adapted to other communication tasks.


Assuntos
COVID-19/diagnóstico , COVID-19/psicologia , Comunicação , Informática Médica/organização & administração , Informática Médica/normas , Pandemias , Participação do Paciente , SARS-CoV-2/isolamento & purificação , COVID-19/epidemiologia , COVID-19/virologia , Alemanha , Humanos , Fatores de Tempo
7.
BMC Med Inform Decis Mak ; 20(1): 29, 2020 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-32046701

RESUMO

BACKGROUND: Modern data driven medical research promises to provide new insights into the development and course of disease and to enable novel methods of clinical decision support. To realize this, machine learning models can be trained to make predictions from clinical, paraclinical and biomolecular data. In this process, privacy protection and regulatory requirements need careful consideration, as the resulting models may leak sensitive personal information. To counter this threat, a wide range of methods for integrating machine learning with formal methods of privacy protection have been proposed. However, there is a significant lack of practical tools to create and evaluate such privacy-preserving models. In this software article, we report on our ongoing efforts to bridge this gap. RESULTS: We have extended the well-known ARX anonymization tool for biomedical data with machine learning techniques to support the creation of privacy-preserving prediction models. Our methods are particularly well suited for applications in biomedicine, as they preserve the truthfulness of data (e.g. no noise is added) and they are intuitive and relatively easy to explain to non-experts. Moreover, our implementation is highly versatile, as it supports binomial and multinomial target variables, different types of prediction models and a wide range of privacy protection techniques. All methods have been integrated into a sound framework that supports the creation, evaluation and refinement of models through intuitive graphical user interfaces. To demonstrate the broad applicability of our solution, we present three case studies in which we created and evaluated different types of privacy-preserving prediction models for breast cancer diagnosis, diagnosis of acute inflammation of the urinary system and prediction of the contraceptive method used by women. In this process, we also used a wide range of different privacy models (k-anonymity, differential privacy and a game-theoretic approach) as well as different data transformation techniques. CONCLUSIONS: With the tool presented in this article, accurate prediction models can be created that preserve the privacy of individuals represented in the training set in a variety of threat scenarios. Our implementation is available as open source software.


Assuntos
Confidencialidade , Anonimização de Dados , Sistemas de Apoio a Decisões Clínicas , Modelos Estatísticos , Software , Pesquisa Biomédica , Humanos , Aprendizado de Máquina , Curva ROC , Reprodutibilidade dos Testes
8.
Dis Esophagus ; 32(8)2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31329831

RESUMO

Risk stratification in patients with Barrett's esophagus (BE) to prevent the development of esophageal adenocarcinoma (EAC) is an unsolved task. The incidence of EAC and BE is increasing and patients are still at unknown risk. BarrettNET is an ongoing multicenter prospective cohort study initiated to identify and validate molecular and clinical biomarkers that allow a more personalized surveillance strategy for patients with BE. For BarrettNET participants are recruited in 20 study centers throughout Germany, to be followed for progression to dysplasia (low-grade dysplasia or high-grade dysplasia) or EAC for >10 years. The study instruments comprise self-administered epidemiological information (containing data on demographics, lifestyle factors, and health), as well as biological specimens, i.e., blood-based samples, esophageal tissue biopsies, and feces and saliva samples. In follow-up visits according to the individual surveillance plan of the participants, sample collection is repeated. The standardized collection and processing of the specimen guarantee the highest sample quality. Via a mobile accessible database, the documentation of inclusion, epidemiological data, and pathological disease status are recorded subsequently. Currently the BarrettNET registry includes 560 participants (23.1% women and 76.9% men, aged 22-92 years) with a median follow-up of 951 days. Both the design and the size of BarrettNET offer the advantage of answering research questions regarding potential causes of disease progression from BE to EAC. Here all the integrated methods and materials of BarrettNET are presented and reviewed to introduce this valuable German registry.


Assuntos
Adenocarcinoma/diagnóstico , Esôfago de Barrett/complicações , Detecção Precoce de Câncer/métodos , Neoplasias Esofágicas/diagnóstico , Vigilância da População/métodos , Medição de Risco/métodos , Adenocarcinoma/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Regras de Decisão Clínica , Progressão da Doença , Neoplasias Esofágicas/etiologia , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sistema de Registros , Fatores de Risco , Adulto Jovem
9.
BMC Med Inform Decis Mak ; 17(1): 30, 2017 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-28330491

RESUMO

BACKGROUND: Translational researchers need robust IT solutions to access a range of data types, varying from public data sets to pseudonymised patient information with restricted access, provided on a case by case basis. The reason for this complication is that managing access policies to sensitive human data must consider issues of data confidentiality, identifiability, extent of consent, and data usage agreements. All these ethical, social and legal aspects must be incorporated into a differential management of restricted access to sensitive data. METHODS: In this paper we present a pilot system that uses several common open source software components in a novel combination to coordinate access to heterogeneous biomedical data repositories containing open data (open access) as well as sensitive data (restricted access) in the domain of biobanking and biosample research. Our approach is based on a digital identity federation and software to manage resource access entitlements. RESULTS: Open source software components were assembled and configured in such a way that they allow for different ways of restricted access according to the protection needs of the data. We have tested the resulting pilot infrastructure and assessed its performance, feasibility and reproducibility. CONCLUSIONS: Common open source software components are sufficient to allow for the creation of a secure system for differential access to sensitive data. The implementation of this system is exemplary for researchers facing similar requirements for restricted access data. Here we report experience and lessons learnt of our pilot implementation, which may be useful for similar use cases. Furthermore, we discuss possible extensions for more complex scenarios.


Assuntos
Bancos de Espécimes Biológicos/normas , Pesquisa Biomédica/normas , Segurança Computacional/normas , Conjuntos de Dados como Assunto , Pesquisa Translacional Biomédica/normas , Humanos , Projetos Piloto
10.
Unfallchirurg ; 120(7): 561-572, 2017 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-28643095

RESUMO

The treatment of superficial wound infections with local antibiotics is considered to be problematic as it is accompanied by an increased risk of resistance development and ineffectiveness in deeper regions. On the contrary, the local application of antibiotics is useful in arthroplasty and necessary if implants are utilized. The reason for this is the prevention of a rapid biofilm formation on foreign implants and a resulting infection may remain undiscovered until it becomes chronic. Apart from exogenous material, necrotic tissue (e. g. bone sequestra) provides suitable retreat areas for pathogens in the body. Because of the characteristics of bone and joint infections and an exceptional infection recurrence rate, a combined approach is required. Systemic antibiotic prophylaxis is able to reduce the number of pathogens acquired by perioperative contamination or hematogenic spread from another focus of infection; however, systemically applied antibiotics often fail to form an effective colonization barrier around the implant because their ability to penetrate the bone is relatively low. On the other hand, the high concentration of locally released antibiotics leads to an effective protection of the implant from bacteria in situ. Thus, for the treatment of implant-associated infections, systemic and local application of anti-infective agents is a reliable adjuvant measure that improves the therapeutic success. Polymethylmethacrylate (PMMA) bone cement is the most commonly used local drug carrier. Based on clinical and microbiological results, microbiologists and infectious disease experts together with the surgeon and pharmacist determine which anti-infective agents are indicated for systemic and local, PMMA cement-related application. Because there is no evident concept for the local application, unlike the recommendation for systemic use of anti-infective agents, this review article describes which aspects should be taken into account.


Assuntos
Antibacterianos/administração & dosagem , Infecção dos Ferimentos/tratamento farmacológico , Administração Tópica , Antibioticoprofilaxia , Artroplastia , Artroplastia de Substituição , Biofilmes/efeitos dos fármacos , Portadores de Fármacos , Quimioterapia Combinada , Humanos , Polimetil Metacrilato , Infecções Relacionadas à Prótese/tratamento farmacológico , Infecção da Ferida Cirúrgica/tratamento farmacológico
11.
BMC Med Inform Decis Mak ; 16: 49, 2016 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-27130179

RESUMO

BACKGROUND: Privacy must be protected when sensitive biomedical data is shared, e.g. for research purposes. Data de-identification is an important safeguard, where datasets are transformed to meet two conflicting objectives: minimizing re-identification risks while maximizing data quality. Typically, de-identification methods search a solution space of possible data transformations to find a good solution to a given de-identification problem. In this process, parts of the search space must be excluded to maintain scalability. OBJECTIVES: The set of transformations which are solution candidates is typically narrowed down by storing the results obtained during the search process and then using them to predict properties of the output of other transformations in terms of privacy (first objective) and data quality (second objective). However, due to the exponential growth of the size of the search space, previous implementations of this method are not well-suited when datasets contain many attributes which need to be protected. As this is often the case with biomedical research data, e.g. as a result of longitudinal collection, we have developed a novel method. METHODS: Our approach combines the mathematical concept of antichains with a data structure inspired by prefix trees to represent properties of a large number of data transformations while requiring only a minimal amount of information to be stored. To analyze the improvements which can be achieved by adopting our method, we have integrated it into an existing algorithm and we have also implemented a simple best-first branch and bound search (BFS) algorithm as a first step towards methods which fully exploit our approach. We have evaluated these implementations with several real-world datasets and the k-anonymity privacy model. RESULTS: When integrated into existing de-identification algorithms for low-dimensional data, our approach reduced memory requirements by up to one order of magnitude and execution times by up to 25 %. This allowed us to increase the size of solution spaces which could be processed by almost a factor of 10. When using the simple BFS method, we were able to further increase the size of the solution space by a factor of three. When used as a heuristic strategy for high-dimensional data, the BFS approach outperformed a state-of-the-art algorithm by up to 12 % in terms of the quality of output data. CONCLUSIONS: This work shows that implementing methods of data de-identification for real-world applications is a challenging task. Our approach solves a problem often faced by data custodians: a lack of scalability of de-identification software when used with datasets having realistic schemas and volumes. The method described in this article has been implemented into ARX, an open source de-identification software for biomedical data.


Assuntos
Algoritmos , Confidencialidade , Informática Médica/métodos , Modelos Estatísticos , Humanos
12.
Cell Tissue Bank ; 17(4): 629-642, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27631323

RESUMO

The rising number of primary joint replacements worldwide causes an increase of revision surgery of endoprostheses due bacterial infection. Revision surgery using non-cemented implants seems beneficial for the long-term outcome and the use of antibiotic-impregnated bone grafts might control the infection and give a good support for the implant. In this study we evaluated the release of antibiotics from fresh-frozen and lyophilized allogeneic bone grafts. Lyophilized bone chips and fresh frozen bone chips were mixed with gentamicin sulphate, gentamicin palmitate, vancomycin, calcium carbonate/calcium sulphate impregnated with gentamicin sulphate, and calcium carbonate/calcium sulphate bone substitute material impregnated with vancomycin. The efficacy of each preparation was measured by drug release tests and bacterial susceptibility using B. subtilis, S. aureus and methicillin-resistant Staphylococcus aureus. The release of gentamicin from lyophilized bone was similar to the release rate from fresh frozen bone during all the experimental time. That fact might be related to the similar porosity and microstructure of the bone chips. The release of gentamicin from lyophilized and fresh frozen bone was high in the first and second day, decreasing and keeping a low rate until the end of the second week. Depending on the surgical strategy either polymethylmethacrylate or allogeneic bone are able to deliver sufficient concentrations of gentamicin to achieve bacterial inhibition within two weeks after surgery. In case of uncemented revision of joint replacements allogeneic bone is able to deliver therapeutic doses of gentamicin and peak levels immediately after implantation during a fortnight. The use of lyophilized and fresh frozen bone allografts as antibiotic carriers is recommended for prophylaxis of bone infection.


Assuntos
Antibacterianos/administração & dosagem , Portadores de Fármacos/química , Cabeça do Fêmur/química , Cabeça do Fêmur/transplante , Gentamicinas/administração & dosagem , Vancomicina/administração & dosagem , Aloenxertos/química , Aloenxertos/microbiologia , Antibacterianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Substitutos Ósseos/química , Transplante Ósseo , Cabeça do Fêmur/microbiologia , Liofilização , Gentamicinas/farmacologia , Humanos , Doadores Vivos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Transplante Homólogo , Vancomicina/farmacologia
13.
Artigo em Alemão | MEDLINE | ID: mdl-26809823

RESUMO

BACKGROUND: In addition to the Biobanking and BioMolecular resources Research Initiative (BBMRI), which is establishing a European research infrastructure for biobanks, a network for large European prospective cohorts (LPC) is being built to facilitate transnational research into important groups of diseases and health care. One instrument for this is the database "LPC Catalogue," which supports access to the biomaterials of the participating cohorts. OBJECTIVES: To present the LPC Catalogue as a relevant tool for connecting European biobanks. In addition, the LPC Catalogue has been extended to establish compatibility with existing Minimum Information About Biobank data Sharing (MIABIS) and to allow for more detailed search requests. This article describes the LPC Catalogue, its organizational and technical structure, and the aforementioned extensions. MATERIALS AND METHODS: The LPC Catalogue provides a structured overview of the participating LPCs. It offers various retrieval possibilities and a search function. To support more detailed search requests, a new module has been developed, called a "data cube". The provision of data by the cohorts is being supported by a "connector" component. RESULTS: The LPC Catalogue contains data on 22 cohorts and more than 3.8 million biosamples. At present, data on the biosamples of three cohorts have been acquired for the "cube," which is continuously being expanded. In the BBMRI-LPC, tendering for scientific projects using the data and samples of the participating cohorts is currently being carried out. In this context, several proposals have already been approved. CONCLUSIONS: The LPC Catalogue is supporting transnational access to biosamples. A comparison with existing solutions illustrates the relevance of its functionality.


Assuntos
Bancos de Espécimes Biológicos/organização & administração , Pesquisa Biomédica/organização & administração , Catálogos como Assunto , Sistemas de Gerenciamento de Base de Dados/organização & administração , Bases de Dados Factuais , Relações Interinstitucionais , Estudos de Coortes , Europa (Continente) , Previsões , Disseminação de Informação/métodos , Armazenamento e Recuperação da Informação/métodos , Modelos Organizacionais , Sistema de Registros , Manejo de Espécimes/métodos
14.
J Biomed Inform ; 58: 37-48, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26385376

RESUMO

OBJECTIVE: With the ARX data anonymization tool structured biomedical data can be de-identified using syntactic privacy models, such as k-anonymity. Data is transformed with two methods: (a) generalization of attribute values, followed by (b) suppression of data records. The former method results in data that is well suited for analyses by epidemiologists, while the latter method significantly reduces loss of information. Our tool uses an optimal anonymization algorithm that maximizes output utility according to a given measure. To achieve scalability, existing optimal anonymization algorithms exclude parts of the search space by predicting the outcome of data transformations regarding privacy and utility without explicitly applying them to the input dataset. These optimizations cannot be used if data is transformed with generalization and suppression. As optimal data utility and scalability are important for anonymizing biomedical data, we had to develop a novel method. METHODS: In this article, we first confirm experimentally that combining generalization with suppression significantly increases data utility. Next, we proof that, within this coding model, the outcome of data transformations regarding privacy and utility cannot be predicted. As a consequence, existing algorithms fail to deliver optimal data utility. We confirm this finding experimentally. The limitation of previous work can be overcome at the cost of increased computational complexity. However, scalability is important for anonymizing data with user feedback. Consequently, we identify properties of datasets that may be predicted in our context and propose a novel and efficient algorithm. Finally, we evaluate our solution with multiple datasets and privacy models. RESULTS: This work presents the first thorough investigation of which properties of datasets can be predicted when data is anonymized with generalization and suppression. Our novel approach adopts existing optimization strategies to our context and combines different search methods. The experiments show that our method is able to efficiently solve a broad spectrum of anonymization problems. CONCLUSION: Our work shows that implementing syntactic privacy models is challenging and that existing algorithms are not well suited for anonymizing data with transformation models which are more complex than generalization alone. As such models have been recommended for use in the biomedical domain, our results are of general relevance for de-identifying structured biomedical data.


Assuntos
Serviços de Informação/economia , Serviços de Informação/normas , Segurança Computacional , Modelos Teóricos , Privacidade
15.
J Mater Sci Mater Med ; 26(1): 5344, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25578698

RESUMO

In this study HERAFILL(®) granules containing gentamicin was evaluated as a bone void filling material once mixed with allograft bone grafts. The efficacy of the bone grafts mixed with HERAFILL(®) was measured by drug release tests and bacterial susceptibility using Bacillus subtilis, Staphylococcus epidermidis and Staphylococcus aureus. The effect of storage at -80 °C on the delivery and efficacy of gentamicin from bone grafts mixed with HERAFILL(®) was also investigated. Higher elution of gentamicin was detected in all stored groups (1 and 6 months) in comparison with non-stored samples. The gentamicin elution released from all groups was efficient on reducing S. aureus and S. epidermidis CFU. The susceptibility tests using S. aureus showed less resistance of the strain after 1 month of the elution storage. That resistance was not observed after 6 months of storage. The capacity of bone grafts to act as gentamicin carriers has been confirmed in this study. The different granules sizes did not interfere in the delivery rate of the antibiotics or in the activity against the bacteria. Storage at -80 °C does not interfere on the antibiotic activity.


Assuntos
Antibacterianos/química , Materiais Biocompatíveis/química , Substitutos Ósseos/química , Transplante Ósseo/métodos , Carbonato de Cálcio/química , Sulfato de Cálcio/química , Fêmur/efeitos dos fármacos , Antibacterianos/administração & dosagem , Artroplastia de Quadril , Bacillus subtilis/efeitos dos fármacos , Bioensaio , Sistemas de Liberação de Medicamentos , Gentamicinas/administração & dosagem , Gentamicinas/química , Humanos , Testes de Sensibilidade Microbiana , Ortopedia , Ácido Palmítico/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos
16.
BMC Med Inform Decis Mak ; 15: 100, 2015 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-26621059

RESUMO

BACKGROUND: Collaborative collection and sharing of data have become a core element of biomedical research. Typical applications are multi-site registries which collect sensitive person-related data prospectively, often together with biospecimens. To secure these sensitive data, national and international data protection laws and regulations demand the separation of identifying data from biomedical data and to introduce pseudonyms. Neither the formulation in laws and regulations nor existing pseudonymization concepts, however, are precise enough to directly provide an implementation guideline. We therefore describe core requirements as well as implementation options for registries and study databases with sensitive biomedical data. METHODS: We first analyze existing concepts and compile a set of fundamental requirements for pseudonymized data management. Then we derive a system architecture that fulfills these requirements. Next, we provide a comprehensive overview and a comparison of different technical options for an implementation. Finally, we develop a generic software solution for managing pseudonymized data and show its feasibility by describing how we have used it to realize two research networks. RESULTS: We have found that pseudonymization models are highly heterogeneous, already on a conceptual level. We have compiled a set of requirements from different pseudonymization schemes. We propose an architecture and present an overview of technical options. Based on a selection of technical elements, we suggest a generic solution. It supports the multi-site collection and management of biomedical data. Security measures are multi-tier pseudonymity and physical separation of data over independent backend servers. Integrated views are provided by a web-based user interface. Our approach has been successfully used to implement a national and an international rare disease network. CONCLUSIONS: We were able to identify a set of core requirements out of several pseudonymization models. Considering various implementation options, we realized a generic solution which was implemented and deployed in research networks. Still, further conceptual work on pseudonymity is needed. Specifically, it remains unclear how exactly data is to be separated into distributed subsets. Moreover, a thorough risk and threat analysis is needed.


Assuntos
Pesquisa Biomédica/normas , Confidencialidade/normas , Conjuntos de Dados como Assunto/normas , Guias como Assunto/normas , Sistema de Registros/normas , Humanos
17.
Int J Behav Nutr Phys Act ; 11(1): 28, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-24575796

RESUMO

BACKGROUND: Elderly people obtain significant health benefits from physical activity (PA), but the role of activity patterns has scarcely been researched. The present study aims to describe the patterns of PA among different intensities of activity in elderly people. We assess how patterns differ between more and less active groups ('rare', 'average', and 'frequent'), and explore whether and how various PA parameters are associated with functional exercise capacity (FEC). METHODS: PA was measured in 168 subjects (78 males; 65-89 years of age), using a triaxial GT3X accelerometer for ten consecutive days. Subjects were divided into three groups by activity and the groups were compared. A multiple linear regression model was used to predict FEC. RESULTS: Participants greater than or equal to 80 years are most prone to being sedentary for long periods, while women and the obese are the groups most likely to spend insufficient time in moderate to vigorous PA (MVPA). Rarely active elderly people had a decreased proportion of long bouts of MVPA and light PA and of short bouts in sedentary behavior than frequently active subjects did (p<0.001). As predictors of FEC, younger age, lower BMI, male sex, better lung function, absence of multimorbidity, longer times and longer bouts of MVPA emerged as significant parameters (r(2)=0.54). Patterns of MVPA explained most of the variance. CONCLUSIONS: PA patterns provide information beyond reports of activity alone. MVPA in elderly people may be increased by increasing the proportion of long bouts, in order to increase FEC as well as average PA. However, health conditions may limit PA. In rarely active people (often with reduced FEC, worse lung function, and diagnosis of multimorbidity or disability), longer periods of time in light PA may be sufficient to increase the overall level of activity.


Assuntos
Acelerometria , Atividade Motora , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Modelos Lineares , Masculino , Obesidade/metabolismo , Comportamento Sedentário , Inquéritos e Questionários
18.
J Biomed Inform ; 50: 62-76, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24333850

RESUMO

Sensitive biomedical data is often collected from distributed sources, involving different information systems and different organizational units. Local autonomy and legal reasons lead to the need of privacy preserving integration concepts. In this article, we focus on anonymization, which plays an important role for the re-use of clinical data and for the sharing of research data. We present a flexible solution for anonymizing distributed data in the semi-honest model. Prior to the anonymization procedure, an encrypted global view of the dataset is constructed by means of a secure multi-party computing (SMC) protocol. This global representation can then be anonymized. Our approach is not limited to specific anonymization algorithms but provides pre- and postprocessing for a broad spectrum of algorithms and many privacy criteria. We present an extensive analytical and experimental evaluation and discuss which types of methods and criteria are supported. Our prototype demonstrates the approach by implementing k-anonymity, ℓ-diversity, t-closeness and δ-presence with a globally optimal de-identification method in horizontally and vertically distributed setups. The experiments show that our method provides highly competitive performance and offers a practical and flexible solution for anonymizing distributed biomedical datasets.


Assuntos
Sistemas Computadorizados de Registros Médicos , Privacidade , Algoritmos , Modelos Teóricos
19.
Cell Tissue Bank ; 15(1): 139-44, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23793827

RESUMO

During surgery with bone grafting, the impaction of bone tissue creates an avascular area where local circulation is disrupted. If infections arise, they may prevent systemically administered antibiotics from reaching the infected bone. In this study we evaluated gentamicin palmitate (GP) mixed with gentamicin sulfate (GS) as a coating for bone chips (BCh). The efficacy of the coated BCh was measured by gentamicin base release tests using B. subtilis, S. epidermidis and S. aureus. Gentamicin base release was evaluated in phosphate-buffered saline for up to 7 days using B. subtilis bioassay. Antimicrobial efficacy was tested with S. aureus and S. epidermidis. A significant difference on the release of gentamicin base between GS and GS + GP was observed. S. epidermidis are significantly more susceptible to GS + GP and GS than S. aureus. BCh can act as gentamicin carriers and showed efficacy against S. aureus and S. epidermidis.


Assuntos
Antibioticoprofilaxia/métodos , Transplante Ósseo/métodos , Osso e Ossos/microbiologia , Gentamicinas/farmacologia , Infecções por Bactérias Gram-Positivas/prevenção & controle , Aloenxertos , Antibacterianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Desinfecção , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Humanos , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos
20.
Orthopadie (Heidelb) ; 53(3): 163-175, 2024 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-37889315

RESUMO

BACKGROUND: Hip and knee implants can be either fixated without cement, press-fit, or with bone cement. Real-world data from arthroplasty registers, as well as studies, provide a broad database for the discussion of cemented versus uncemented arthroplasty procedures. OBJECTIVES: What is the recommendation for cemented or cementless anchorage of hip and knee implants based on the current evidence from international arthroplasty registries and meta-analyses? METHODS: A recommendation is generated by means of a direct comparison of data from the arthroplasty registries of eight different countries (USA, Germany, Australia, UK, Sweden, Norway, New Zealand, and The Netherlands), the comparison of 22 review studies and meta-analyses based on registry data, as well as the evaluation of the recommendation of healthcare systems of different nations. For this purpose, reviews and meta-analyses whose results were statistically significant were selected, as were the annual reports of the arthroplasty registries that were current at the time of writing. RESULTS: For knee endoprostheses, a long survival time, as well as a lower risk of revision can be achieved with the help of cemented anchorage with antibiotic-laden bone cement. In patients aged 70 years and older, cemented anchorage of the hip stem implant significantly reduces the risk of intraoperative or postoperative periprosthetic fracture (times four), this applies both to elective total hip arthroplasties (TEPs) and to hemiarthroplasty after femoral neck fractures. Antibiotic-loaded bone cement significantly (p = 0.041) reduces the risk of periprosthetic infection, especially in patients with femoral neck fractures. CONCLUSIONS: Total knee replacement with antibiotic-loaded bone cement is well established in Germany and evidence based. Registry data and meta-analyses recommend cemented fixation of the hip stem in older patients-in Germany the evidence-based recommendations must still be transferred to daily practice.


Assuntos
Artroplastia de Quadril , Fraturas do Colo Femoral , Prótese de Quadril , Humanos , Idoso , Idoso de 80 Anos ou mais , Cimentos Ósseos/uso terapêutico , Falha de Prótese , Reoperação , Desenho de Prótese , Artroplastia de Quadril/efeitos adversos , Antibacterianos , Fraturas do Colo Femoral/cirurgia
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