174 research outputs found
When is Better Best? A multiobjective perspective
Purpose: To identify the most informative methods for reporting results of
treatment planning comparisons.
Methods: Seven papers from the past year of International Journal of
Radiation Oncology Biology Physics reported on comparisons of treatment plans
for IMRT and IMAT. The papers were reviewed to identify methods of comparisons.
Decision theoretical concepts were used to evaluate the study methods and
highlight those that provide the most information.
Results: None of the studies examined the correlation between objectives.
Statistical comparisons provided some information but not enough to make
provide support for a robust decision analysis.
Conclusion: The increased use of treatment planning studies to evaluate
different methods in radiation therapy requires improved standards for
designing the studies and reporting the results
Matrisomal components involved in regenerative wound healing in axolotl and acomys: implications for biomaterial development
Achieving regeneration in humans has been a long-standing goal of many researchers. Whereas amphibians like the axolotl (Ambystoma mexicanum) are capable of regenerating whole organs and even limbs, most mammals heal their wounds via fibrotic scarring. Recently, the African spiny mouse (Acomys sp.) has been shown to be injury resistant and capable of regenerating several tissue types. A major focal point of research with Acomys has been the identification of drivers of regeneration. In this search, the matrisome components related to the extracellular matrix (ECM) are often overlooked. In this review, we compare Acomys and axolotl skin wound healing and blastema-mediated regeneration by examining their wound healing responses and comparing the expression pattern of matrisome genes, including glycosaminoglycan (GAG) related genes. The goal of this review is to identify matrisome genes that are upregulated during regeneration and could be potential candidates for inclusion in pro-regenerative biomaterials. Research papers describing transcriptomic or proteomic coverage of either skin regeneration or blastema formation in Acomys and axolotl were selected. Matrisome and GAG related genes were extracted from each dataset and the resulting lists of genes were compared. In our analysis, we found several genes that were consistently upregulated, suggesting possible involvement in regenerative processes. Most of the components have been implicated in regulation of cell behavior, extracellular matrix remodeling and wound healing. Incorporation of such pro-regenerative factors into biomaterials may help to shift pro-fibrotic processes to regenerative responses in treated wounds.European Unionβs Horizon 2020 ;Grant Agreement No. 955722info:eu-repo/semantics/publishedVersio
Systematic review and metaanalysis comparing the bias and accuracy of the modification of diet in renal disease and chronic kidney disease epidemiology collaboration equations in community-based population
BACKGROUND
The majority of patients with chronic kidney disease are diagnosed and monitored in primary care. Glomerular filtration rate (GFR) is a key marker of renal function, but direct measurement is invasive; in routine practice, equations are used for estimated GFR (eGFR) from serum creatinine. We systematically assessed bias and accuracy of commonly used eGFR equations in populations relevant to primary care.
CONTENT
MEDLINE, EMBASE, and the Cochrane Library were searched for studies comparing measured GFR (mGFR) with eGFR in adult populations comparable to primary care and reporting both the Modification of Diet in Renal Disease (MDRD) and the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations based on standardized creatinine measurements. We pooled data on mean bias (difference between eGFR and mGFR) and on mean accuracy (proportion of eGFR within 30% of mGFR) using a random-effects inverse-variance weighted metaanalysis. We included 48 studies of 26875 patients that reported data on bias and/or accuracy. Metaanalysis of within-study comparisons in which both formulae were tested on the same patient cohorts using isotope dilution-mass spectrometry-traceable creatinine showed a lower mean bias in eGFR using CKD-EPI of 2.2 mL/min/1.73 m2 (95% CI, 1.1β3.2; 30 studies; I2 = 74.4%) and a higher mean accuracy of CKD-EPI of 2.7% (1.6β3.8; 47 studies; I2 = 55.5%). Metaregression showed that in both equations bias and accuracy favored the CKD-EPI equation at higher mGFR values.
SUMMARY
Both equations underestimated mGFR, but CKD-EPI gave more accurate estimates of GFR
A two minute liquid based sample preparation for rapid SARS-CoV2 real-time PCR screening: a multicentre evaluation
Background: Apart from major health concerns associated to the SARS-coronavirus-2 (SARS-CoV-2) pandemic, also the diagnostic workflow encountered serious problems. Limited availability of kit components, buffers and even plastics has resulted in suboptimal testing procedures worldwide. Alternative workflows have been implemented to overcome these difficulties. Recently a liquid based sample prep has been launched as solution to overcome limitations in relation to nucleic acid extraction.Objective: Multicenter evaluation of the QlAprep& Viral RNA UM kit (QIA P&A) for rapid sample preparation and real-time PCR detection of SARS-CoV-2 in comparison to standardized laboratory testing methods.Study design: Selected samples of the routine diagnostic workflow at Clinical Microbiology Laboratories of four Dutch hospitals have been subjected to the rapid QIA P&A protocol and the results have been compared to routine diagnostic data.Results: Combining results of manual and automated procedures, a total of 377 clinical samples of which 202 had been tested positive with a wide range of C-T values, showed almost complete concordance in the QIA P&A assay for samples up to C-T values of 33 with one exception of C-T 31. Prospectively 60 samples were tested and also showed 100 % concordance with 5 positives. The method has been automated by two centres.Conclusions: Despite an input of only 8 mu L of clinical sample, the QIA P&A kit showed good performance for sample preparation and amplification of SARS-CoV-2 and can contribute as a rapid molecular testing strategy in managing the CoV-2 pandemic.Molecular basis of virus replication, viral pathogenesis and antiviral strategie
National Protocol for Model-Based Selection for Proton Therapy in Head and Neck Cancer
In the Netherlands, the model-based approach is used to identify patients with head and neck cancer who may benefit most from proton therapy in terms of prevention of late radiation-induced side effects in comparison with photon therapy. To this purpose, a National Indication Protocol Proton therapy for Head and Neck Cancer patients (NIPP-HNC) was developed, which has been approved by the health care authorities. When patients qualify according to the guidelines of the NIPP-HNC, proton therapy is fully reimbursed. This article describes the procedures that were followed to develop this NIPP-HNC and provides all necessary information to introduce model-based selection for patients with head and neck cancer into routine clinical practice.</p
Comparison of central corneal thickness and anterior chamber depth measurements using three imaging technologies in normal eyes and after phakic intraocular lens implantation
Contains fulltext :
81835.pdf (Publisherβs version ) (Open Access)BACKGROUND: The repeatability and interchangeability of imaging devices measuring central corneal thickness (CCT) and anterior chamber depth (ACD) are important in the assessment of patients considering refractive surgery. The purpose of this study was to investigate the agreement of CCT and ACD measurements using three imaging technologies in healthy eyes and in eyes after phakic intraocular lens implantation (pIOL). METHODS: In this comparative study, CCT and ACD were measured using anterior segment optical coherence tomography (AS-OCT), Orbscan II, and Pentacam in 33 healthy volunteers (66 eyes) and 22 patients (42 eyes) after pIOL implantation. Intraobserver repeatability was evaluated for all three devices in the healthy volunteer group. RESULTS: Pairwise comparison of CCT measurements showed significant differences between all devices (P < 0.001), except for the AS-OCT and Orbscan II in the healthy volunteer group (P = 0.422) and the Orbscan II and Pentacam in the pIOL group (P = 0.214). ACD measurements demonstrated significant differences between all pairwise comparisons in both groups (P < or = 0.001). Intraobserver reliability was high for CCT and ACD measurements in the healthy volunteer group, with coefficients of variation ranging from 0.6% to 1.2% and 0.4% to 0.5% respectively. CONCLUSIONS: CCT and ACD measurements using AS-OCT, Orbscan II, and Pentacam demonstrated high intraobserver reliability. However, these devices should not be used interchangeably for measurements of CCT and ACD in healthy subject and patients after pIOL implantation
Diagnosing serious infections in acutely ill children in ambulatory care (ERNIE 2 study protocol, part A): diagnostic accuracy of a clinical decision tree and added value of a point-of-care C-reactive protein test and oxygen saturation
Synchrotron radiation-based experimental determination of the optimal energy for cell radiotoxicity enhancement following photoelectric effect on stable iodinated compounds
This study was designed to experimentally evaluate the optimal X-ray energy for increasing the radiation energy absorbed in tumours loaded with iodinated compounds, using the photoelectric effect. SQ20B human cells were irradiated with synchrotron monochromatic beam tuned at 32.8, 33.5, 50 and 70 keV. Two cell treatments were compared to the control: cells suspended in 10 mg ml1 of iodine radiological contrast agent or cells pre-exposed with 10 mM of iodo-desoxyuridine (IUdR) for 48 h. Our radiobiological end point was clonogenic cell survival. Cells irradiated with both iodine compounds exhibited a radiation sensitisation enhancement. Moreover, it was energy dependent, with a maximum at 50 keV. At this energy, the sensitisation calculated at 10% survival was equal to 2.03 for cells suspended in iodinated contrast agent and 2.60 for IUdR. Cells pretreated with IUdR had higher sensitisation factors over the energy range than for those suspended in iodine contrast agent. Also, their survival curves presented no shoulder, suggesting complex lethal damages from Auger electrons. Our results confirm the existence of the 50 keV energy optimum for a binary therapeutic irradiation based on the presence of stable iodine in tumours and an external irradiation. Monochromatic synchrotron radiotherapy concept is hence proposed for increasing the differential effect between healthy and cancerous tissue irradiation
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