Automated, Point-of-Care mobile flow cytometry: Bringing the laboratory to the sample

Background

Innate effector cells are very responsive to infectious and inflammatory cues found in damaged and inflamed tissues. Their activation is a potential target to assess the state of the immune system. Unfortunately, these cells are very susceptible for ex-vivo activation, hampering accurate interpretation of flow cytometry data. Whether a brief window exists before ex-vivo activation starts to occur is currently unknown.

Aims

1) This study extensively investigated ex-vivo activation of innate effector cells over time. 2) We tested the feasibility of applying a mobile, automated, flow cytometry laboratory for out-of-hospital Point-of-Care analyses to minimize ex-vivo activation bias.

Methods

1) Ex-vivo neutrophil, eosinophil and monocyte activation in a blood collection tube over time and the reactivity to a formyl-peptide was investigated in a healthy cohort. 2) To facilitate fast, out-of-hospital analysis, application of the mobile flow cytometry was tested by placing an automated flow cytometer into a van. The stability of the setup was assessed by repetitively measuring laser alignment and fluorescence verification beads.

Findings

1) Immediately after venipuncture activation marker expression on neutrophils, eosinophils and monocyte subsets started to change in a time-dependent manner. 2) The mobile flow cytometry laboratory travelled over 3000 km, performing measurements at 19 locations with a median single-person-set-up time of 14 min. The laser alignment and fluorescence were stable during all experiments.

Conclusions

Accurate flow data of innate immune cells are only obtained when ex-vivo activation is kept to minimum. The use of a mobile, fast, automated, flow cytometry laboratory for out-of-hospital Point-of-Care analyses provides new investigational and diagnostic possibilities outside major hospital flow cytometry laboratories.

DEATH AND DYING IN GREEN CARE FARMS

Green care farms form an alternative to traditional nursing homes for people with dementia and combine agriculture production with health-related, social and educational services. Twenty-four-hour care green care farms offer end-of-life care. The aim of the study was to explore the experiences of healthcare workers and family caregivers with end-of-life care for people with dementia who died on a green care farm in the Netherlands. Semi-structured, in-depth interviews were conducted to explore their experiences with end-of-life care, including topics such as advance care planning, bereavement support and the influence of COVID-19. The study showed that most experiences were characterized by personal attention for the resident and family caregivers, and tailored holistic care. The duration of the dying phase was typically short, and most residents remained active until their final days. Despite the COVID-19 measures, healthcare workers and family caregivers still experienced adequate end-of-life care.

"When I am breathless now, I don't have the fear that's linked to it": a case series on the potential of EMDR to break the dyspnea-anxiety cycle in COPD

BACKGROUND

Expectations can enhance the intensity and the neural processing of breathlessness. Previous breathlessness episodes may influence the perception of subsequent episodes because of psycho-traumatic consequences. In post-traumatic stress disorder, eye movement desensitization and reprocessing (EMDR) is the therapy of choice.

AIMS AND OBJECTIVES

We explored the hypothesis that EMDR in patients with chronic obstructive pulmonary disease (COPD) and previous severe breathlessness episodes, improves breathlessness mastery by decreasing the anxiety component.

METHODS

As we found no literature on previous research on this subject, we undertook a qualitative case series on four patients with COPD GOLD 4/D and refractory breathlessness who wished to undergo EMDR for psychotraumatic breathlessness episodes. Amongst others, we used the Chronic Respiratory Disease Questionnaire (CRQ) before and after EMDR, and semi-structured, face-to-face, in-depth interviews.

RESULTS

All patients had between three and five EMDR sessions. On CRQ, subset mastery, three patients had a large improvement and one patient a moderate improvement. On subset emotional functioning, three patients showed a large improvement and one showed no change. All patients made a distinction between 'regular' breathlessness and breathlessness intertwined with anxiety. They all stated that the anxiety component of their breathlessness diminished or disappeared. All four would recommend EMDR for other COPD patients.

CONCLUSION

There is ground for a randomized controlled clinical trial to test the effects of EMDR on breathlessness mastery in a subset of COPD patients with previous severe breathlessness episodes and high levels of anxiety.

Neutrophil and Eosinophil Responses Remain Abnormal for Several Months in Primary Care Patients With COVID-19 Disease

Introduction

Neutrophil and eosinophil activation and its relation to disease severity has been understudied in primary care patients with COVID-19. In this study, we investigated whether the neutrophil and eosinophil compartment were affected in primary care patients with COVID-19.

Methods

COVID-19 patients, aged ≥ 40 years with cardiovascular comorbidity presenting to the general practitioner with substantial symptoms, partaking in the COVIDSat@Home study between January and April 2021, were included. Blood was drawn during and 3 to 6 months after active COVID-19 disease and analyzed by automated flow cytometry, before and after stimulation with a formyl-peptide (fNLF). Mature neutrophil and eosinophil markers at both time points were compared to healthy controls. A questionnaire was conducted on disease symptoms during and 3 to 6 months after COVID-19 disease.

Results

The blood of 18 COVID-19 patients and 34 healthy controls was analyzed. During active COVID-19 disease, neutrophils showed reduced CD10 (p = 0.0360), increased CD11b (p = 0.0002) and decreased CD62L expression (p < 0.0001) compared to healthy controls. During active COVID-19 disease, fNLF stimulated neutrophils showed decreased CD10 levels (p < 0.0001). Three to six months after COVID-19 disease, unstimulated neutrophils showed lowered CD62L expression (p = 0.0003) and stimulated neutrophils had decreased CD10 expression (p = 0.0483) compared to healthy controls. Both (un)stimulated CD10 levels increased 3 to 6 months after active disease (p = 0.0120 and p < 0.0001, respectively) compared to during active disease. Eosinophil blood counts were reduced during active COVID-19 disease and increased 3 to 6 months after infection (p < 0.0001). During active COVID-19, eosinophils showed increased unstimulated CD11b (p = 0.0139) and decreased (un)stimulated CD62L expression (p = 0.0036 and p = 0.0156, respectively) compared to healthy controls. Three to six months after COVID-19 disease, (un)stimulated eosinophil CD62L expression was decreased (p = 0.0148 and p = 0.0063, respectively) and the percentage of CD11bbright cells was increased (p = 0.0083 and p = 0.0307, respectively) compared to healthy controls.

Conclusion

Automated flow cytometry analysis reveals specific mature neutrophil and eosinophil activation patterns in primary care patients with COVID-19 disease, during and 3 to 6 months after active disease. This suggests that the neutrophil and eosinophil compartment are long-term affected by COVID-19 in primary care patients. This indicates that these compartments may be involved in the pathogenesis of long COVID.

Ottawa classification for symptomatic acetabular dysplasia assessment of interobserver and intraobserver reliability

Aims

The aim of the current study was to assess the reliability of the Ottawa classification for symptomatic acetabular dysplasia.

Methods

In all, 134 consecutive hips that underwent periacetabular osteotomy were categorized using a validated software (Hip2Norm) into four categories of normal, lateral/global, anterior, or posterior. A total of 74 cases were selected for reliability analysis, and these included 44 dysplastic and 30 normal hips. A group of six blinded fellowship-trained raters, provided with the classification system, looked at these radiographs at two separate timepoints to classify the hips using standard radiological measurements. Thereafter, a consensus meeting was held where a modified flow diagram was devised, before a third reading by four raters using a separate set of 74 radiographs took place.

Results

Intrarater results per surgeon between Time 1 and Time 2 showed substantial to almost perfect agreement among the raters (κappa = 0.416 to 0.873). With respect to inter-rater reliability, at Time 1 and Time 2 there was substantial agreement overall between all surgeons (Time 1 κappa = 0.619; Time 2 κappa = 0.623). Posterior and anterior rating categories had moderate and fair agreement at Time 1 (posterior κappa = 0.557; anterior κappa = 0.438) and Time 2 (posterior κappa = 0.506; anterior κappa = 0.250), respectively. At Time 3, overall reliability (κappa = 0.687) and posterior and anterior reliability (posterior κappa = 0.579; anterior κappa = 0.521) improved from Time 1 and Time 2.

Conclusion

The Ottawa classification system provides a reliable way to identify three categories of acetabular dysplasia that are well-aligned with surgical management. The term ‘borderline dysplasia’ should no longer be used.

Cite this article: Bone Joint Res. 2020;9(5):242–249.

The Khorana score for prediction of venous thromboembolism in cancer patients: a systematic review and meta-analysis

We aimed to evaluate the performance of the Khorana score in predicting venous thromboembolic events in ambulatory cancer patients. Embase and MEDLINE were searched from January 2008 to June 2018 for studies which evaluated the Khorana score. Two authors independently screened studies for eligibility, extracted data, and assessed risk of bias. Additional data on the 6-month incidence of venous thromboembolism were sought by contacting corresponding authors. The incidence in each Khorana score risk group was estimated with random effects meta-analysis. A total of 45 articles and eight abstracts were included, comprising 55 cohorts enrolling 34,555 ambulatory cancer patients. For 27,849 patients (81%), 6-month follow-up data were obtained. Overall, 19% of patients had a Khorana score of 0 points, 64% a score of 1 or 2 points, and 17% a score of 3 or more points. The incidence of venous thromboembolism in the first six months was 5.0% (95%CI: 3.9-6.5) in patients with a low-risk Khorana score (0 points), 6.6% (95%CI: 5.6-7.7) in those with an intermediate-risk Khorana score (1 or 2 points), and 11.0% (95%CI: 8.8-13.8) in those with a high-risk Khorana score (3 points or higher). Of the patients with venous thromboembolism in the first six months, 23.4% (95%CI: 18.4-29.4) had been classified as high risk according to the Khorana score. In conclusion, the Khorana score can be used to select ambulatory cancer patients at high risk of venous thromboembolism for thromboprophylaxis; however, most events occur outside this high-risk group.

Comparison of risk prediction scores for venous thromboembolism in cancer patients: a prospective cohort study

In ambulatory patients with solid cancer, routine thromboprophylaxis to prevent venous thromboembolism is not recommended. Several risk prediction scores to identify cancer patients at high risk of venous thromboembolism have been proposed, but their clinical usefulness remains a matter of debate. We evaluated and directly compared the performance of the Khorana, Vienna, PROTECHT, and CONKO scores in a multinational, prospective cohort study. Patients with advanced cancer were eligible if they were due to undergo chemotherapy or had started chemotherapy in the previous three months. The primary outcome was objectively confirmed symptomatic or incidental deep vein thrombosis or pulmonary embolism during a 6-month follow-up period. A total of 876 patients were enrolled, of whom 260 (30%) had not yet received chemotherapy. Fifty-three patients (6.1%) developed venous thromboembolism. The c-statistics of the scores ranged from 0.50 to 0.57. At the conventional positivity threshold of 3 points, the scores classified 13–34% of patients as high-risk; the 6-month incidence of venous thromboembolism in these patients ranged from 6.5% (95%CI: 2.8–12) for the Khorana score to 9.6% (95%CI: 6.6–13) for the PROTECHT score. High-risk patients had a significantly increased risk of venous thromboembolism when using the Vienna (subhazard ratio 1.7; 95%CI: 1.0–3.1) or PROTECHT (subhazard ratio 2.1; 95%CI: 1.2–3.6) scores. In conclusion, the prediction scores performed poorly in predicting venous thromboembolism in cancer patients. The Vienna CATS and PROTECHT scores appear to discriminate better between low- and high-risk patients, but further improvements are needed before they can be considered for introduction into clinical practice.

Performance of a cylindrical diode array for use in a 1.5 T MR-linac

At the UMC Utrecht, a linear accelerator with integrated magnetic resonance imaging (MRI) has been developed, the MR-linac. Patient-specific quality assurance (QA) of treatment plans for MRI-based image guided radiotherapy requires QA equipment compatible with this 1.5 T magnetic field. The purpose of this study was to examine the performance characteristics of the ArcCHECK-MR in a transverse 1.5 T magnetic field. To this end, the short-term reproducibility, dose linearity, dose rate dependence, field size dependence, dose per pulse dependence and inter-diode dose response variation of the ArcCHECK-MR diode array were evaluated on a conventional linac and on the MR-linac. The ArcCHECK-MR diode array performed well for all tests on both linacs, no significant differences in performance characteristics were observed. Differences in the maximum dose deviations between both linacs were less than 1.5%. Therefore, we conclude that the ArcCHECK-MR can be used in a transverse 1.5 T magnetic field.

Raman spectroscopic analysis of isomers of biliverdin dimethyl ester

The constitutional isomers of biliverdin dimethyl ester, IX alpha and XIII alpha, were studied by resonance Raman spectroscopy. The far-reaching spectral similarities suggest that despite the different substitution patterns, the compositions of the normal modes are closely related. This conclusion does not hold only for the parent state (ZZZ, sss configuration) but also for the configurational isomers which were obtained upon double-bond photoisomerization. Based on a comparison of the resonance Raman spectra, a EZZ configuration is proposed for one of the two photoisomers of biliverdin dimethyl ester IX alpha, while a ZZE, ssa configuration has been assigned previously to the second isomer.

A coherent pattern among social behavior, blood pressure, corticosterone and catecholamine measures in individual male rats

Behavioral and physiological responses of 18 chronically cannulated male TMD-S3 rats were assessed during various social interactions with conspecifics, both with and without the possibility for physical contact (social vs. psychosocial stimulation). Response magnitudes (behavior, blood pressure, plasma catecholamines) depend upon both the social environmental requirements (offense, defense, psychosocial stimulus following defense) and individual characteristics. The more competitive males generally reacted with higher responses of blood pressure and catecholamines than more passive rats. In addition, these competitive males had higher baseline levels of noradrenaline. The present experiment shows that male rats differ in the individual sympathetic tone and reactivity in relation to their behavior in a social environment.