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We report an investigation of peripheral blood polymorphonuclear leukocytes (PMN) from untreated patients with mild, quiescent psoriasis. Four aspects of the ‘metabolic burst’ were measured to illustrate phagocytosis-related events. These were: myeloperoxidase activity, hydrogen peroxide release, superoxide production and luminol-amplified chemiluminescence. Our study does not support the concept of an intrinsic abnormality of the PMN in psoriasis, but provides additional evidence for disease activity-dependent changes in phagocytic behaviour. Possible interactions with certain humoral factors, the so-called opsonins, are discussed. [ABSTRACT FROM AUTHOR]

This article studies that cyclic AMP is decreased in mononuclear leukocytes from psoriasis patients. Certain abnormalities of monocyte function have recently been described which seem to be characteristic of the psoriatic individual, occurring even in the absence of cutaneous lesions. These include increased chemotaxis, increased phagocytic capacity and increased bacteriocidal capacity. The cyclic AMP measurements are presented in the table. The reduction in 'resting' levels in the psoriatic MNL is statistically significant and that following adrenaline stimulation is probably significant.

Esophageal cancer can be treated effectively with esophagectomy; however, the postoperative complication rate is high. In this paper, we study to what extent machine learning methods can predict anastomotic leakage and pneumonia up to two days in advance. We use a dataset with 417 patients who underwent esophagectomy between 2011 and 2021. The dataset contains multimodal temporal information, specifically, laboratory results, vital signs, thorax images, and preoperative patient characteristics. The best models scored mean test set AUROCs of 0.87 and 0.82 for leakage 1 and 2 days ahead, respectively. For pneumonia, this was 0.74 and 0.61 for 1 and 2 days ahead, respectively. We conclude that machine learning models can effectively predict anastomotic leakage and pneumonia after esophagectomy.

Understanding the diagnostic goal of medical reports is valuable information for understanding patient flows. This work focuses on extracting the reason for taking an MRI scan of Multiple Sclerosis (MS) patients using the attached free-form reports: Diagnosis, Progression or Monitoring. We investigate the performance of domain-dependent and general state-of-the-art language models and their alignment with domain expertise. To this end, eXplainable Artificial Intelligence (XAI) techniques are used to acquire insight into the inner workings of the model, which are verified on their trustworthiness. The verified XAI explanations are then compared with explanations from a domain expert, to indirectly determine the reliability of the model. BERTje, a Dutch Bidirectional Encoder Representations from Transformers (BERT) model, outperforms RobBERT and MedRoBERTa.nl in both accuracy and reliability. The latter model (MedRoBERTa.nl) is a domain-specific model, while BERTje is a generic model, showing that domain-specific models are not always superior. Our validation of BERTje in a small prospective study shows promising results for the potential uptake of the model in a practical setting.

Proximal femur fractures represent a major health concern, and substantially contribute to the morbidity of elderly. Correct classification and diagnosis of hip fractures has a significant impact on mortality, costs and hospital stay. In this paper, we present a method and empirical validation for automatic subclassification of proximal femur fractures and Dutch radiological report generation that does not rely on manually curated data. The fracture classification model was trained on 11,000 X-ray images obtained from 5000 electronic health records in a general hospital. To generate the Dutch reports, we first trained an embedding model on 20,000 radiological reports of pelvic region fractures, and used its embeddings in the report generation model. We trained the report generation model on the 5000 radiological reports associated with the fracture cases. Our report generation model is on par with state-of-the-art in terms of BLEU and ROUGE scores. This is promising, because in contrast to those earlier works, our approach does not require manual preprocessing of either images or the reports. This boosts the applicability of automatic clinical report generation in practice. A quantitative and qualitative user study among medical students found no significant difference in provenance of real and generated reports. A qualitative, in-depth clinical relevance study with medical domain experts showed that from a human perspective the quality of the generated reports approximates the quality of the original reports and highlights challenges in creating sufficiently detailed and versatile training data for automatic radiology report generation., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Hospitals often set protocols based on well defined standards to maintain the quality of patient reports. To ensure that the clinicians conform to the protocols, quality assurance of these reports is needed. Patient reports are currently written in free-text format, which complicates the task of quality assurance. In this paper, we present a machine learning based natural language processing system for automatic quality assurance of radiology reports on breast cancer. This is achieved in three steps: we i) identify the top-level structure (headings) of the report, ii) classify the report content into the top-level headings, and iii) convert the free-text detailed findings in the report to a semi-structured format (post-structuring). Top level structure and content of report were predicted with an F1 score of 0.97 and 0.94, respectively, using Support Vector Machine (SVM) classifiers. For automatic structuring, our proposed hierarchical Conditional Random Field (CRF) outperformed the baseline CRF with an F1 score of 0.78 versus 0.71. The determined structure of the report is represented in semi-structured XML format of the free-text report, which helps to easily visualize the conformance of the findings to the protocols. This format also allows easy extraction of specific information for other purposes such as search, evaluation, and research.

Processes in organisations, such as hospitals, may deviate from the intended standard processes, due to unforeseeable events and the complexity of the organisation. For hospitals, the knowledge of actual patient streams for patient populations (e.g., severe or non-severe cases) is important for quality control and improvement. Process discovery from event data in electronic health records can shed light on the patient flows, but their comparison for different populations is cumbersome and time-consuming. In this paper, we present an approach for the automatic comparison of process models that were extracted from events in electronic health records. Concretely, we propose comparing processes for different patient populations by cross-log conformance checking, and standard graph similarity measures obtained from the directed graph underlying the process model. We perform a user study with 20 participants in order to obtain a ground truth for similarity of process models. We evaluate our approach on two data sets, the publicly available MIMIC database with the focus on different cancer patients in intensive care, and a database on breast cancer patients from a Dutch hospital. In our experiments, we found average fitness to be a good indicator for visual similarity in the ZGT use case, while the average precision and graph edit distance are strongly correlated with visual impression for cancer process models on MIMIC. These results are a call for further research and evaluation for determining which similarity or combination of similarities is needed in which type of process model comparison.

Objective: To determine iron-induced free radical damage in fetal rhesus haemolytic disease (RHD) before and after repeated intrauterine red blood cell transfusions and its relation to hydrops fetalis., Design: Prospective, observational study., Setting: Department of Obstetrics, Leiden University Medical Centre, the Netherlands., Population: Fifty anaemic fetuses, including 13 hydropic ones, 9 preterm and 12 term neonates and 8 female non-pregnant adults., Methods: Venous blood plasma samples were collected from 50 fetuses suffering from RHD preliminary to the first, and if appropriate, subsequent intrauterine red blood cell transfusions for determination of iron status including non-protein-bound iron (NPBI) and iron-binding primary antioxidant proteins, total plasma anti-oxidant capacity and its contributing secondary antioxidants (e.g. vitamin C, uric acid, sulphydryl groups and peroxidation products). Results were compared with values of healthy preterm and term neonates directly at birth and adult controls. Within the fetal haemolytic group, 13 hydropic fetuses were analysed as a separate group., Main Outcome Measures: Non-protein-bound iron, antioxidants, total antioxidant capacity and peroxidation products. Sub analysis of the outcome measures of the hydropic fetuses., Results: RHD fetuses had at initial cordocentesis a significantly higher NPBI level and a significantly lower total plasma antioxidant capacity than control babies and adults. Their vitamin C tended to be more oxidised but lipid peroxidation had not increased, when compared with preterm babies. The repeated intrauterine red blood cell transfusions had a positive effect on the total antioxidant capacity of plasma and did not increase the concentration of NPBI. The hydropic fetuses, who had higher NPBI concentrations and lower plasma protein concentrations and total antioxidant capacity, did not show more peroxidation products in plasma than the non-hydropic fetuses. Fetuses without reversal of hydrops despite intrauterine transfusions showed decreasing levels of proteins with subsequent transfusions but peroxidation products remained constant., Conclusion: Repeated intrauterine red blood cell transfusions do not lead to free radical damage in the fetus in utero. Iron-induced free radical activity does not appear to play a causative role in the proceeding of hydrops fetalis in RHD.

We tested the hypotheses that Ca(2+) concentration ([Ca(2+)]) and sarcomere length (SL) modulate force development via graded effects on cross-bridge kinetics in chemically permeabilized rat cardiac trabeculae. Using sinusoidal length perturbations, we derived the transfer functions of stiffness over a range of [Ca(2+)] at a constant SL of 2.1 micrometer (n = 8) and at SL of 2.0, 2.1, and 2.2 micrometer (n = 4). We found that changes in SL affected only the magnitude of stiffness, whereas [Ca(2+)] affected the magnitude and phase-frequency relations. The data were fit to complex functions of two exponential processes. The characteristic frequencies (b and c) of these processes are indexes of cross-bridge kinetics, with b relating to cross-bridge attachment to and c to detachment from certain non-force-generating states. Both were significantly affected by [Ca(2+)], with an increase in b and c of 140 and 44%, respectively, over the range of [Ca(2+)] studied (P < 0.01). In contrast, SL had no effect on the characteristic frequencies (P > 0.6). We conclude that Ca(2+) activation modulates force development in rat myocardium, at least in part, via a graded effect on cross-bridge kinetics, whereas SL effects are mediated mainly by recruitment of cross bridges.

In a sample of 13 full-term and 10 preterm infants, the development of kicking movements was studied at 6, 12, and 18 weeks (corrected) age. In healthy full-term infants some characteristics are strikingly stable, such as the duration of the flexion and extension phase and the within-joint organization. These parameters did not differ in preterm compared to full-term infants. For other features, however, developmental changes and differences were observed. Full-term infants tended to decrease their kick frequencies slightly with age. In preterm infants much higher initial kick rates were found, followed by a steep decrease, which resulted in kick frequencies comparable to the full-term levels after the (corrected) age of 12 weeks. There is a tight coupling between the movements in the different joints of the leg in full-term newborns. Preterm infants, in contrast, initially show much lower cross-correlations between hip and ankle and between knee and ankle. This is particularly the case for those preterm infants who were born before 32 weeks gestation. Again, the differences resolved after the age of 12 weeks, which might be related to a transformation in neural functions reported previously around this age. The initial differences in the characteristics of kicking appeared to be more readily explainable by differences in neurological condition than by contrasts in leg volume or postural control.

Healthy full-term infants show a developmental trend in head position from an initial right-sided preference to one with the head in midline around the age of 12 weeks. We studied the effects of intrauterine growth retardation (IUGR) and the degree of prematurity on both aspects of development from 35 weeks postmenstrual age to 18 weeks corrected age in 35 preterm infants without overt neurological abnormalities and whose gestational ages ranged from 27 to 34 weeks. Our data reveal that, during the preterm period, infants born after pregnancies of 32 weeks or less showed a lack of right-sided preferences for head turning after release from midline but not for the subsequent maintenance of a position. IUGR did not seem to affect either preference. After term age a right-sided preference diminished while a head midline position increased. The latter was not significantly delayed in relation to birth before 32 weeks gestation or IUGR. However, when infants were classified on the basis of neurological differences as reflected in a (mildly) abnormal movement quality, a delay in the attainment of a midline posture was observed, which suggests it is related to a suboptimal neurological condition. This delay, however, was also accounted for by the side-to-side flattening of the skull.

It is hypothesised that individual differences in nervous system functioning, undetected by a neurological examination, are reflected in the quality of spontaneous movements of preterm newborns. Given this hypothesis it is expected that a short pregnancy duration and IUGR will be related to an abnormal movement quality. These expectations were confirmed in a group of 37 small-for-gestational-age and appropriate-for-gestational-age preterm newborns with gestational ages ranging from 27 to 34 weeks without serious perinatal complications and for whom no overt neurological abnormalities could be detected based on the evaluation of elicited responses and tonus at the postmenstrual age of 35 weeks. The quality of general movements was adversely affected by both IUGR and a pregnancy duration below 32 weeks. Newborns with an abnormal movement quality also had significantly lower obstetrical optimality scores. Previous research has shown these scores to be related to the neurological condition of the newborn. We conclude that observations of movement quality, being neither intrusive nor time consuming, may constitute a useful addition to the neurological assessment of preterm newborns without serious perinatal complications.

Rhythmic oscillations in forehead skin blood flow were studied with the laser Doppler technique in thirteen healthy subjects. During voluntary hyperventilation, a three-fold increase in relative amplitude of the spontaneous rhythmic oscillations in forehead skin blood flow was observed, whereas mean blood flow decreased by 15%. During hyperventilation, the relative amplitude of the oscillations was on average 36% of the mean blood flow value. The mean incidence of the oscillations increased significantly, from 68% of the measuring time before, to 96% of the measuring time during hyperventilation. The oscillation frequency was not affected by hyperventilation. Before, during and after hyperventilation the average oscillation frequency was 0.140 Hz (8.4 min-1), 0.145 Hz (8.7 min-1) respectively. The application of heat or a local anaesthetic to the skin attenuated the relative amplitude of the oscillations in forehead skin blood flow during hyperventilation as well as before and after.