29 research outputs found
Accumulation of defense systems in phage-resistant strains of Pseudomonas aeruginosa
Prokaryotes encode multiple distinct anti-phage defense systems in their genomes. However, the impact of carrying a multitude of defense systems on phage resistance remains unclear, especially in a clinical context. Using a collection of antibiotic-resistant clinical strains of Pseudomonas aeruginosa and a broad panel of phages, we demonstrate that defense systems contribute substantially to defining phage host range and that overall phage resistance scales with the number of defense systems in the bacterial genome. We show that many individual defense systems target specific phage genera and that defense systems with complementary phage specificities co-occur in P. aeruginosa genomes likely to provide benefits in phage-diverse environments. Overall, we show that phage-resistant phenotypes of P. aeruginosa with at least 19 phage defense systems exist in the populations of clinical, antibiotic-resistant P. aeruginosa strains
Assessing the Quality of Clinical Teachers: A Systematic Review of Content and Quality of Questionnaires for Assessing Clinical Teachers
BACKGROUND: Learning in a clinical environment differs from formal educational settings and provides specific challenges for clinicians who are teachers. Instruments that reflect these challenges are needed to identify the strengths and weaknesses of clinical teachers. OBJECTIVE: To systematically review the content, validity, and aims of questionnaires used to assess clinical teachers. DATA SOURCES: MEDLINE, EMBASE, PsycINFO and ERIC from 1976 up to March 2010. REVIEW METHODS: The searches revealed 54 papers on 32 instruments. Data from these papers were documented by independent researchers, using a structured format that included content of the instrument, validation methods, aims of the instrument, and its setting. Results : Aspects covered by the instruments predominantly concerned the use of teaching strategies (included in 30 instruments), supporter role (29), role modeling (27), and feedback (26). Providing opportunities for clinical learning activities was included in 13 instruments. Most studies referred to literature on good clinical teaching, although they failed to provide a clear description of what constitutes a good clinical teacher. Instrument length varied from 1 to 58 items. Except for two instruments, all had to be completed by clerks/residents. Instruments served to provide formative feedback ( instruments) but were also used for resource allocation, promotion, and annual performance review (14 instruments). All but two studies reported on internal consistency and/or reliability; other aspects of validity were examined less frequently. CONCLUSIONS: No instrument covered all relevant aspects of clinical teaching comprehensively. Validation of the instruments was often limited to assessment of internal consistency and reliability. Available instruments for assessing clinical teachers should be used carefully, especially for consequential decisions. There is a need for more valid comprehensive instruments
Successfully sustaining sex and gender issues in undergraduate medical education: a case study
Although several projects have addressed the importance of gender health issues in medical education, the sustainability of change efforts in medical education has rarely been addressed. Understanding the possible facilitators or barriers to sustainability may help to develop future interventions that are effective in maintaining gender health issues as a topic in medical curricula. The aim of this study is to provide a longitudinal evaluation of changes regarding gender health issues that occurred in the past decade and the factors that influenced this process. The coursebooks of eight theoretical courses of the Nijmegen medical curriculum were screened on the basis of criteria for an integrated gender perspective in medical education. To assess the sustainability of gender health issues, the screening results from 2014 were compared with those of a similar project in 2005. In addition, open interviews were conducted with eight coordinators to identify facilitators and barriers influencing the sustainability of gender health issues. Analysis showed that, over the past decade, the implementation of gender health issues was mainly sustained and additional changes were made, resulting in an ongoing gender perspective in the Nijmegen medical curriculum. The coordinators mentioned several factors that influenced the sustainability of implementation in medical education: coordinators' and teachers' gender-sensitive attitude, competing demands, the presence of sex and gender in learning objectives, examinations and evaluation, organizational support and curriculum revisions. Our findings suggest that, in implementing sex and gender in medical education, medical faculties need to focus on top-down support in incorporating sex and gender into core objectives and time spent on incorporating sex and gender into medicine, and on the continuous training of teaching staff
Functionality-packed additively manufactured porous titanium implants
The holy grail of orthopedic implant design is to ward off both aseptic and septic loosening for long enough that the implant outlives the patient. Questing this holy grail is feasible only if orthopedic biomaterials possess a long list of functionalities that enable them to discharge the onerous task of permanently replacing the native bone tissue. Here, we present a rationally designed and additive manufacturing (AM) topologically ordered porous metallic biomaterial that is made from Ti-6Al-4V using selective laser melting and packs most (if not all) of the required functionalities into a single implant. In addition to presenting a fully interconnected porous structure and form-freedom that enables realization of patient-specific implants, the biomaterials developed here were biofunctionalized using plasma electrolytic oxidation to locally release both osteogenic (i.e. strontium) and antibacterial (i.e. silver ions) agents. The same single-step biofunctionalization process also incorporated hydroxyapatite into the surface of the implants. Our measurements verified the continued release of both types of active agents up to 28 days. Assessment of the antibacterial activity in vitro and in an ex vivo murine model demonstrated extraordinarily high levels of bactericidal effects against a highly virulent and multidrug-resistant Staphylococcus aureus strain (i.e. USA300) with total eradication of both planktonic and adherent bacteria. This strong antibacterial behavior was combined with a significantly enhanced osteogenic behavior, as evidenced by significantly higher levels of alkaline phosphatase (ALP) activity compared with non-biofunctionalized implants. Finally, we discovered synergistic antibacterial behavior between strontium and silver ions, meaning that 4β32 folds lower concentrations of silver ions were required to achieve growth inhibition and total killing of bacteria. The functionality-packed biomaterial presented here demonstrates a unique combination of functionalities that make it an advanced prototype of future orthopedic biomaterials where implants will outlive patients.</p
PHYSIOTHERAPY IN RHEUMATOID ARTHRITIS: DEVELOPMENT OF A PRACTICE GUIDELINE
Background: To improve the quality of the physiotherapy management in patients with rheumatoid arthritis (RA) a Dutch practice guideline, based on current scientific evidence and best practice, was developed. This guideline comprised all elements of a structured approach (assessment, treatment and evaluation) and was based on the International Classification of Functioning, disability and Health (ICF) and the ICF core sets for RA.
Methods: A guideline steering committee, comprising 10 expert physiotherapists, selected topics concerning the guideline chapters initial assessment, treatment and evaluation. With respect to treatment a systematic literature search was performed using various databases, and the evidence was graded (1-4). For the initial assessment and evaluation mainly review papers and textbooks were used. Based on evidence and expert opinion, recommendations were formulated. A first draft of the guideline was reviewed by 10 experts from different professional backgrounds resulting in the final guideline.
Results: In total 7 topics were selected. For the initial assessment, three recommendations were made. Based on the ICF core sets for RA a list of health problems relevant for the physiotherapist was made and completed with red flags and points of attention. Concerning treatment, three recommendations were formulated; both exercise therapy and education on physiotherapy were recommended, whereas passive interventions (delivery of heat or cold, mechanical, electric and electromagnetic energy, massage, passive mobilization/manipulation and balneotherapy) were neither recommended nor discouraged. For treatment evaluation at the level of activities and participation, the Health Assessment Questionnaire was recommended. For evaluating specific body structures and functions the handheld dynamometer, 6-minute walk test or Astrand bicycle test (including Borg-scale for rating the perceived exertion), Escola Paulista de Medicina Range of Motion Scale and a Visual Analog Scale for pain and morning stiffness were recommended.
Conclusion: This physiotherapy practice guideline for RA included seven recommendations on the initial assessment, treatment and evaluation, which were all based on the ICF and the ICF Core Set for RA. The implementation of the guideline in clinical practice needs further evaluation.Pathophysiology and treatment of rheumatic disease
Functionality-packed additively manufactured porous titanium implants
The holy grail of orthopedic implant design is to ward off both aseptic and septic loosening for long enough that the implant outlives the patient. Questing this holy grail is feasible only if orthopedic biomaterials possess a long list of functionalities that enable them to discharge the onerous task of permanently replacing the native bone tissue. Here, we present a rationally designed and additive manufacturing (AM) topologically ordered porous metallic biomaterial that is made from Ti-6Al-4V using selective laser melting and packs most (if not all) of the required functionalities into a single implant. In addition to presenting a fully interconnected porous structure and form-freedom that enables realization of patient-specific implants, the biomaterials developed here were biofunctionalized using plasma electrolytic oxidation to locally release both osteogenic (i.e. strontium) and antibacterial (i.e. silver ions) agents. The same single-step biofunctionalization process also incorporated hydroxyapatite into the surface of the implants. Our measurements verified the continued release of both types of active agents up to 28 days. Assessment of the antibacterial activity in vitro and in an ex vivo murine model demonstrated extraordinarily high levels of bactericidal effects against a highly virulent and multidrug-resistant Staphylococcus aureus strain (i.e. USA300) with total eradication of both planktonic and adherent bacteria. This strong antibacterial behavior was combined with a significantly enhanced osteogenic behavior, as evidenced by significantly higher levels of alkaline phosphatase (ALP) activity compared with non-biofunctionalized implants. Finally, we discovered synergistic antibacterial behavior between strontium and silver ions, meaning that 4β32 folds lower concentrations of silver ions were required to achieve growth inhibition and total killing of bacteria. The functionality-packed biomaterial presented here demonstrates a unique combination of functionalities that make it an advanced prototype of future orthopedic biomaterials where implants will outlive patients.Biomaterials & Tissue BiomechanicsMechanical, Maritime and Materials Engineerin
Functionality-packed additively manufactured porous titanium implants
The holy grail of orthopedic implant design is to ward off both aseptic and septic loosening for long enough that the implant outlives the patient. Questing this holy grail is feasible only if orthopedic biomaterials possess a long list of functionalities that enable them to discharge the onerous task of permanently replacing the native bone tissue. Here, we present a rationally designed and additive manufacturing (AM) topologically ordered porous metallic biomaterial that is made from Ti-6Al-4V using selective laser melting and packs most (if not all) of the required functionalities into a single implant. In addition to presenting a fully interconnected porous structure and form-freedom that enables realization of patient-specific implants, the biomaterials developed here were biofunctionalized using plasma electrolytic oxidation to locally release both osteogenic (i.e. strontium) and antibacterial (i.e. silver ions) agents. The same single-step biofunctionalization process also incorporated hydroxyapatite into the surface of the implants. Our measurements verified the continued release of both types of active agents up to 28 days. Assessment of the antibacterial activity in vitro and in an ex vivo murine model demonstrat