18 research outputs found
Proximal Esophageal Cancer
Proximal esophageal cancer (PEC) is a highly mortal cancer with a five-year survival rate of 30%. Because second primary tumors could decrease survival in PEC patients, this research is aiming at finding out about tumors associated with PEC and their infuence on survival. With the use of a database with PEC patients, diagnosed between 1989 and 2014, it was found that head and neck cancers (H&N) are the most prevalent previous tumor in PEC patients. Previous tumors have a negative effect on surivval. Prospective studies are needed to investigate on the effectiveness of prevention and surveillance methods for H&N patients
A prospective observational study
Background: Severe bacterial infections remain a major challenge in intensive
care units because of their high prevalence and mortality. Adequate antibiotic
exposure has been associated with clinical success in critically ill patients.
The objective of this study was to investigate the target attainment of
standard meropenem dosing in a heterogeneous critically ill population, to
quantify the impact of the full renal function spectrum on meropenem exposure
and target attainment, and ultimately to translate the findings into a tool
for practical application. Methods: A prospective observational single-centre
study was performed with critically ill patients with severe infections
receiving standard dosing of meropenem. Serial blood samples were drawn over 4
study days to determine meropenem serum concentrations. Renal function was
assessed by creatinine clearance according to the Cockcroft and Gault equation
(CLCRCG). Variability in meropenem serum concentrations was quantified at the
middle and end of each monitored dosing interval. The attainment of two
pharmacokinetic/pharmacodynamic targets (100%T>MIC, 50%T>4×MIC) was evaluated
for minimum inhibitory concentration (MIC) values of 2 mg/L and 8 mg/L and
standard meropenem dosing (1000 mg, 30-minute infusion, every 8 h).
Furthermore, we assessed the impact of CLCRCG on meropenem concentrations and
target attainment and developed a tool for risk assessment of target non-
attainment. Results: Large inter- and intra-patient variability in meropenem
concentrations was observed in the critically ill population (n = 48).
Attainment of the target 100%T>MIC was merely 48.4% and 20.6%, given MIC
values of 2 mg/L and 8 mg/L, respectively, and similar for the target
50%T>4×MIC. A hyperbolic relationship between CLCRCG (25–255 ml/ minute) and
meropenem serum concentrations at the end of the dosing interval (C8h) was
derived. For infections with pathogens of MIC 2 mg/L, mild renal impairment up
to augmented renal function was identified as a risk factor for target non-
attainment (for MIC 8 mg/L, additionally, moderate renal impairment).
Conclusions: The investigated standard meropenem dosing regimen appeared to
result in insufficient meropenem exposure in a considerable fraction of
critically ill patients. An easy- and free-to-use tool (the MeroRisk
Calculator) for assessing the risk of target non-attainment for a given renal
function and MIC value was developed
Role of renal function in risk assessment of target non-attainment after standard dosing of meropenem in critically ill patients: a prospective observational study
Background: Severe bacterial infections remain a major challenge in intensive care units because of their high prevalence and mortality. Adequate antibiotic exposure has been associated with clinical success in critically ill patients. The objective of this study was to investigate the target attainment of standard meropenem dosing in a heterogeneous critically ill population, to quantify the impact of the full renal function spectrum on meropenem exposure and target attainment, and ultimately to translate the findings into a tool for practical application.
Methods: A prospective observational single-centre study was performed with critically ill patients with severe infections receiving standard dosing of meropenem. Serial blood samples were drawn over 4 study days to determine meropenem serum concentrations. Renal function was assessed by creatinine clearance according to the Cockcroft and Gault equation (CLCRCG). Variability in meropenem serum concentrations was quantified at the middle and end of each monitored dosing interval. The attainment of two pharmacokinetic/pharmacodynamic targets 100%T >MIC,50%T >4×MIC) was evaluated for minimum inhibitory concentration (MIC) values of 2 mg/L and 8 mg/L and standard meropenem dosing (1000 mg, 30-minute infusion, every 8 h). Furthermore, we assessed the impact of CLCRCG on meropenem concentrations and target attainment and developed a tool for risk assessment of target non-attainment.
Results: Large inter- and intra-patient variability in meropenem concentrations was observed in the critically ill population (n = 48). Attainment of the target 100%T >MIC was merely 48.4% and 20.6%, given MIC values of 2 mg/L and 8 mg/L, respectively, and similar for the target 50%T >4×MIC. A hyperbolic relationship between CLCRCG (25–255 ml/minute) and meropenem serum concentrations at the end of the dosing interval (C8h) was derived. For infections with pathogens of MIC 2 mg/L, mild renal impairment up to augmented renal function was identified as a risk factor for target non-attainment (for MIC 8 mg/L, additionally, moderate renal impairment).
Conclusions: The investigated standard meropenem dosing regimen appeared to result in insufficient meropenem exposure in a considerable fraction of critically ill patients. An easy- and free-to-use tool (the MeroRisk Calculator) for assessing the risk of target non-attainment for a given renal function and MIC value was developed. Trial registration Clinicaltrials.gov, NCT01793012 . Registered on 24 January 2013
Role of renal function in risk assessment of target non-attainment after standard dosing of meropenem in critically ill patients: a prospective observational study
Distributed optimization of multi-class SVMs.
Training of one-vs.-rest SVMs can be parallelized over the number of classes in a straight forward way. Given enough computational resources, one-vs.-rest SVMs can thus be trained on data involving a large number of classes. The same cannot be stated, however, for the so-called all-in-one SVMs, which require solving a quadratic program of size quadratically in the number of classes. We develop distributed algorithms for two all-in-one SVM formulations (Lee et al. and Weston and Watkins) that parallelize the computation evenly over the number of classes. This allows us to compare these models to one-vs.-rest SVMs on unprecedented scale. The results indicate superior accuracy on text classification data
Computational methods for metastasis detection in lymph nodes and characterization of the metastasis-free lymph node microarchitecture: A systematic-narrative hybrid review
Background: Histological examination of tumor draining lymph nodes (LNs) plays a vital role in cancer staging and prognostication. However, as soon as a LN is classed as metastasis-free, no further investigation will be performed and thus, potentially clinically relevant information detectable in tumor-free LNs is currently not captured. Objective: To systematically study and critically assess methods for the analysis of digitized histological LN images described in published research. Methods: A systematic search was conducted in several public databases up to December 2023 using relevant search terms. Studies using brightfield light microscopy images of hematoxylin and eosin or immunohistochemically stained LN tissue sections aiming to detect and/or segment LNs, their compartments or metastatic tumor using artificial intelligence (AI) were included. Dataset, AI methodology, cancer type, and study objective were compared between articles. Results: A total of 7201 articles were collected and 73 articles remained for detailed analyses after article screening. Of the remaining articles, 86% aimed at LN metastasis identification, 8% aimed at LN compartment segmentation, and remaining focused on LN contouring. Furthermore, 78% of articles used patch classification and 22% used pixel segmentation models for analyses. Five out of six studies (83%) of metastasis-free LNs were performed on publicly unavailable datasets, making quantitative article comparison impossible. Conclusions: Multi-scale models mimicking multiple microscopy zooms show promise for computational LN analysis. Large-scale datasets are needed to establish the clinical relevance of analyzing metastasis-free LN in detail. Further research is needed to identify clinically interpretable metrics for LN compartment characterization
1-factorization.
<p>Illustration of the solution of the 1-factorization problem of a graph with many nodes. Node 8 gets arranged centrally and at each step the pattern is rotated by one.</p