Clinical Field Research Articles

Cardiac function in a large animal model of myocardial infarction at 7 T: deep learning based automatic segmentation increases reproducibility

Cardiac magnetic resonance (CMR) imaging allows precise non-invasive quantification of cardiac function. It requires reliable image segmentation for myocardial tissue. Clinically used software usually offers automatic approaches for this step. These are, however, designed for segmentation of human images obtained at clinical field strengths. They reach their limits when applied to preclinical data and ultrahigh field strength (such as CMR of pigs at 7 T). In our study, eleven animals (seven with myocardial infarction) underwent four CMR scans each. Short-axis cine stacks were acquired and used for functional cardiac analysis. End-systolic and end-diastolic images were labelled manually by two observers and inter- and intra-observer variability were assessed. Aiming to make the functional analysis faster and more reproducible, an established deep learning (DL) model for myocardial segmentation in humans was re-trained using our preclinical 7 T data (n = 772 images and labels). We then tested the model on n = 288 images. Excellent agreement in parameters of cardiac function was found between manual and DL segmentation: For ejection fraction (EF) we achieved a Pearson’s r of 0.95, an Intraclass correlation coefficient (ICC) of 0.97, and a Coefficient of variability (CoV) of 6.6%. Dice scores were 0.88 for the left ventricle and 0.84 for the myocardium.

The Personality Inventory for DSM-5-Brief Form (PID-5-BF): Psychometric indicators in a Brazilian community sample

Objective: To investigate psychometric properties (internal structure, convergent/discriminant validity, internal consistency, and test-retest) of the Personality Inventory for DSM-5-Brief Form (PID-5-BF) in a Brazilian community sample. Method: This is a study with a psychometric design. A sample of 527 adults from the general population (69.9% women; 33.5 ± 14.0 years; 74.0% ≥ 12 years education) responded to the instrument online after the study was disseminated on social networks and to the researchers’ contacts. The NEO-PI-R and sociodemographic questionnaire were applied besides the PID-5-BF, and a retest was applied 15-30 days after the initial assessment for reliability assessment. Data were analyzed using statistical techniques (IBM SPSS19 and Factor20); the significance level was set at p ≤ 0.05 for all the analyses. Results: Internal consistency was verified using Cronbach’s alpha and was adequate (domains α ≥ 0.69; total α = 0.87), in addition to test-retest reliability (domains ICC ≥ 0.82; total ICC = 0.95). Divergences were found between the PID-5-BF different domains despite them being significantly correlated with each other. Convergent validity with the NEO-PI-R was adequate, with moderate/strong correlations between the domains theoretically associated (r > 0.38). The internal structure (Exploratory Factor Analysis) indicated that the original five-factor model (CFI = 0.991; TLI = 0.986; RMSEA = 0.033) and one-factor model were adequate (CFI = 0.908; TLI = 0.899; RMSEA = 0.089. Conclusions: The findings support using the PID-5-BF Brazilian version, which presented adequate psychometric properties comparable to the original version. This instrument can be helpful in the clinical and research fields to screen general and specific traits of personality pathology. Future studies are suggested to expand the psychometric findings among clinical samples, confirming the instrument’s scope of reach.

Clinicopathological Differences between Right and Left Colorectal Cancer by Sex

Background: Until now, studies on colorectal cancer (CRC) have focused on clinicopathological characteristics based on location without considering sex differences. However, as men and women have fundamentally different physiological characteristics, research results in the clinical field are limited. We aimed to elucidate the differences in the clinicopathological characteristics between right-sided CRC (RCC) and left-sided CRC (LCC) according to sex. Methods: We classified 1492 South Korean patients with no history of colon surgery between July 2005 and June 2015 based on tumor location and sex. For these patients, differences in the clinical characteristics according to sex were compared using univariate and multivariate analyses. Results: Of the 1269 patients, 951 (74.9%) had LCC, and 318 (25.1%) had RCC, making LCC approximately three times more common than RCC. When sex was not taken into account, patients with RCC had significantly higher rates of anemia and undifferentiated cancers than the rates in those with LCC. Even considering sex, anemia and undifferentiated cancer were more prevalent in RCC than in LCC in both men and women. In contrast, age over 65 years and abnormal white blood cell count differed between RCC and LCC only in women. Conclusions: The clinicopathologic characteristics of CRC vary according to the location and sex. Therefore, sex must be considered as a fundamental characteristic of personalized treatment.

Reference Standards for C-Peptide in Korean Population: A Korean Endocrine Hormone Reference Standard Data Center Study.

The Korean Endocrine Hormone Reference Standard Data Center (KEHRS DC) has created reference standards (RSs) for endocrine hormones since 2020. This study is the first of its kind, wherein the KEHRS DC established RSs for serum Cpeptide levels in a healthy Korean population. Healthy Korean adults were recruited from May 2021 to September 2023. After excluding participants according to our criteria, serum samples were collected; each participant could then choose between fasting glucose only or fasting glucose plus an oral glucose tolerance test (OGTT). If their sample showed high glucose (≥100 mg/dL) or hemoglobin A1c (HbA1c) (≥5.70%), their C-peptide levels were excluded from analyzing the RSs. A total of 1,532 participants were recruited; however, only the data of 1,050 participants were analyzed after excluding those whose samples showed hyperglycemia or high HbA1c. Post-30-minute OGTT data from 342 subjects and post-120-minute OGTT data from 351 subjects were used. The means±2 standard deviations and expanded uncertainties of fasting, post-30-minute and 120-minute OGTT C-peptide levels were 1.26±0.82 and 0.34-3.18, 4.74±3.57 and 1.14-8.33, and 4.85±3.58 and 1.25-8.34 ng/mL, respectively. Serum C-peptide levels correlated with obesity, serum glucose levels, and HbA1c levels. The RSs for serum C-peptide levels established in this study are expected to be useful in both clinical and related fields.

Implementation Barriers and Recommendations for a Multisite Community Health Worker Intervention in Palliative Care for African American Oncology Patients: A Qualitative Study.

Background: Palliative care remains underutilized by African American patients with advanced cancer. Community health workers (CHWs) may help improve palliative care outcomes among this patient population. Objectives: To explore barriers to success of a proposed CHW intervention and synthesize design and implementation recommendations to both optimize our intervention and inform others working to alleviate palliative care disparities. Design: Semi-structured qualitative interviews. Setting/Subjects: Key informants were health care professionals across clinical, leadership, and community health fields. Participants were recruited through purposive sampling from Baltimore, Maryland; Birmingham, Alabama; and Salisbury, Maryland. Measurements: Interviewers used an interview guide grounded in established implementation science models. Data were analyzed through a combined abductive/deductive approach by independent coders. A framework methodology was used to facilitate thematic analysis. Results: In total, 25 professionals completed an interview. Key informants discussed multiple barriers, including at the patient level (lack of knowledge), clinician and facility level (decreased workflow efficiency), and health system level (limited funding). Recommendations related to the intervention's design included high quality preintervention CHW training and full integration of CHWs into the care team to "bridge" divides between outpatient, inpatient, and at-home settings. Intervention delivery recommendations included clearly defining care team roles and balancing flexibility and standardization in CHW support approaches. These recommendations were then used to adapt the planned intervention and its implementation process. Conclusions: Clinicians, cancer center leaders, and CHWs identified multilevel potential barriers to the intervention's success but also described recommendations that may mitigate these barriers. Key informant input represents an important step prior to initiating CHW-based interventions.

E-Health & Innovation to Overcome Barriers in Neuromuscular Diseases. Report from the 3rd eNMD Congress: Pisa, Italy, 29-30 October 2021.

Neuromuscular diseases (NMDs), in their phenotypic heterogeneity, share quite invariably common issues that involve several clinical and socio-economical aspects, needing a deep critical analysis to develop better management strategies. From diagnosis to treatment and follow-up, the development of technological solutions can improve the detection of several critical aspects related to the diseases, addressing both the met and unmet needs of clinicians and patients. Among several aspects of the digital transformation of health and care, this congress expands what has been learned from previous congresses editions on applicability and usefulness of technological solutions in NMDs. In particular the focus on new solutions for remote monitoring provide valuable insights to increase disease-specific knowledge and trigger prompt decision-making. In doing that, several perspectives from different areas of expertise were shared and discussed, pointing out strengths and weaknesses on the current state of the art on topic, suggesting new research lines to advance technology in this specific clinical field.

Evaluation of the Basic Training Program at the School of Ophthalmic Technology

Evaluation of the Basic Training Program at the School of Ophthalmic Technology

Translation, cross-cultural adaptation, and psychometric properties of the Arabic version of the MedRisk instrument for measuring patient satisfaction with physical therapy care

Purpose This study aimed to translate, cross-culturally adapt, and validate the MedRisk Instrument for Measuring Patient Satisfaction with Physical Therapy Care into Arabic (MRPS-Ar). Materials and Methods The 20-Item MRPS was translated and cross-culturally adapted into Arabic following international guidelines. Patients (n = 229) with musculoskeletal conditions who received physical therapy care completed the MRPS-Ar and global rating of change scale. Of these patients, 95 completed the MRPS-Ar twice. Factor structure, floor and ceiling effects, internal consistency, test-retest reliability, and construct validity of the MRPS-Ar were evaluated. Results Principal component analysis suggested 3-factor solution: a 7-item facility experience, 6-item therapeutic experience, and 3-item positive experience. The MRPS-Ar and its factors showed acceptable internal consistency (Cronbach’s alpha coefficients ranged from 0.819 to 0.936) and excellent test-retest reliability (ICCs ranged from 0.965 to 0.983). The global measures of satisfaction were significantly correlated with the global rating of change (Spearman’s rho = −0.678, p < 0.001 for item “overall satisfaction” and Spearman’s rho = −0.690, p < 0.001 for item “would return”). Conclusions The 18-item MRPS-Ar displayed adequate psychometric properties for measuring patients’ satisfaction with physical therapy care. The MRPS-Ar is a reliable and valid instrument that can be used in medical, clinical, and research fields.

Development and evaluation of RFID-integrated endoscopic clips for laparoscopic surgery marking.

As advancements in surgical instruments and techniques continue to evolve, minimally invasive surgery has become increasingly preferred as a means of reducing patient pain and recovery time. However, one major challenge in performing minimally invasive surgery for early gastrointestinal cancer is accurately identifying the location of the lesion. This is particularly difficult when the lesion is confined to the lumen of the intestine and cannot be visually confirmed from the outside during surgery. In such cases, surgeons must rely on CT or endoscopic imaging to locate the lesion. However, if the lesion is difficult to identify with these images or if the surgeon has less experience, it can be challenging to determine its precise location. This can result in an excessive resection margin, deviating from the goal of minimally invasive surgery. To address this challenge, researchers have been studying the development of a marker for identifying the lesion using a radio-frequency identification (RFID) system. One proposed method for clinical application of this detection system is to attach an RFID tag to an endoscopic hemostatic clip and fix it to the intended position, providing a stable marker for the inner wall of the organ. This approach has the potential to improve the accuracy and effectiveness of minimally invasive surgery for early gastrointestinal cancer. In the development of a marker for identifying gastrointestinal lesions using a radio-frequency identification (RFID) system, the shape of the clip and suitable materials for attaching the RFID tag were determined through finite element method (FEM) analysis. A prototype of the clip was then fabricated and ex-vivo experiments were conducted using porcine intestine to evaluate the stability of the clip in relation to its position. To further evaluate the performance of the RFID-integrated clip in vivo, the clip was placed in the gastric wall of the stomach of anesthetized porcine using an endoscopic instrument. The clip was then detected using a RFID detector designed for laparoscopic approach. And later, the accuracy of detection was confirmed by incising the lesion. The design and fabrication of a clip with varying thicknesses using STS316 and STS304 stainless steel were accomplished using the results of finite element method analysis. The stability of the clip was evaluated through ex-vivo experiments, showing it to be a viable option. In-vivo experiments were performed on anesthetized porcine, in which the RFID-integrated clip was placed in the gastric wall and detected using a custom-made RFID detector. The resection margin, measured at about 30 mm from the detector position, was accomplished with low error. These findings indicate the feasibility and efficacy of using an RFID-integrated clip as a marker in minimally invasive surgery for the identification of gastrointestinal lesions. The study evaluated the feasibility of using stainless steel clips for lesion detection in endoscopic surgery using computer-aided engineering analysis and ex-vivo experimentation. Results showed that STS304 was suitable for use while STS316L was not. The ex-vivo experiments revealed that the clip holding force and tissue retention length varied depending on the location of attachment. In-vivo experiments confirmed the accuracy and usefulness of the RFID lesion detection system. However, challenges remain for its use in clinical field, such as ensuring the stability of the clip and the safe attachment of the RFID tag, which requires further research for commercialization.

A unified classification system for HIV-1 5' long terminal repeats.

The HIV-1 provirus mainly consists of internal coding region flanked by 1 long terminal repeats (LTRs) at each terminus. The LTRs play important roles in HIV-1 reverse transcription, integration, and transcription. However, despite of the significant study advances of the internal coding regions of HIV-1 by using definite reference classification, there are no systematic and phylogenetic classifications for HIV-1 5' LTRs, which hinders our elaboration on 5' LTR and a better understanding of the viral origin, spread and therapy. Here, by analyzing all available resources of 5' LTR sequences in public databases following 4 recognized principles for the reference classification, 83 representatives and 14 consensus sequences were identified as representatives of 2 groups, 6 subtypes, 6 sub-subtypes, and 9 CRFs. To test the reliability of the supplemented classification system, the constructed references were applied to identify the 5' LTR assignment of the 22 clinical isolates in China. The results revealed that 16 out of 22 tested strains showed a consistent subtype classification with the previous LTR-independent classification system. However, 6 strains, for which recombination events within 5' LTR were demonstrated, unexpectedly showed a different subtype classification, leading a significant change of binding sites for important transcription factors including SP1, p53, and NF-κB. The binding change of these transcriptional factors would probably affect the transcriptional activity of 5' LTR. This study supplemented a unified classification system for HIV-1 5' LTRs, which will facilitate HIV-1 characterization and be helpful for both basic and clinical research fields.

Effects of Postgraduate Education on Nursing and Reflections in the Clinic Field : A Qualitative Research

Background: Nurses improve themselves with various trainings according to the developing era and patient needs. Determining the effects of postgraduate education in the clinical field opens new horizons for improving the quality of patient care.Aim: To determine the opinions of the participants about the effects of postgraduate education in nursing and the reflection of these effects on the clinic field and patient care by the nurse specialist.Methods: This is a phenomenological descriptive qualitative study which was data gathered through in-depth interviews with nurses, physicians, and patients. For content analysis, the data were subjected to thematic analysis.Results: The data obtained from the views of the participants about the effects of postgraduate education in nursing and its reflections on the clinic were combined under 4 main themes and 20 sub-codes.Conclusions: It was concluded that postgraduate education has effects on nursing roles, individual development, other professional development, increasing its professional value and scientific power, and these  effects are reflected positively in clinical field.

Design and Fabrication of Head Tilt Controlled Wheelchair for Disabled

Abstract: The quantity of crippled people is expanding consistently. Versatility helps are valuable for patients for transportation and are situation for strolling particularly in indoor and outside climate. Moving the patients from wheelchair to cot or to the clinical bed is generally an issue for the chaperon or assistant. Understanding the different issues with respect to the versatility gear and presenting a superior plan will be a resource for the clinical field and assistance for impaired people. There is a requirement for a wheelchair cum cot to work with the debilitated patient's portability and to give an original clinical hardware to use in the Indian emergency clinics. Here we are fostering a framework which is equipped for moving different positions (Seat, Semi-Seat and Cot) physically. T

Catalytic Nanoparticles in Biomedical Applications: Exploiting Advanced Nanozymes for Therapeutics and Diagnostics.

Catalytic nanoparticles (CNPs) as heterogeneous catalyst reveals superior activity due to their physio-chemical features, such as high surface-to-volume ratio and unique optical, electric, and magnetic properties. The CNPs, based on their physio-chemical nature, can either increase the reactive oxygen species (ROS) level for tumor and antibacterial therapy or eliminate the ROS for cytoprotection, anti-inflammation, and anti-aging. In addition, the catalytic activity of nanozymes could specifically trigger a specific reaction accompanied by the optical feature change, presenting the feasibility of biosensor and bioimaging applications. Undoubtedly, CNPs play a pivotal role in pushing the evolution of technologies in medical and clinical fields, and advanced strategies and nanomaterials rely on the input of chemical experts to develop. Herein, we present a systematic and comprehensive review of the challenges and recent development of catalytic NPs for biomedical applications from the viewpoint of advanced nanomaterial with unique catalytic activity and additional functions. Furthermore, we critically discuss the biosafety issue of applying biodegradable and non-biodegradable nanozymes and future perspectives to guide a promising direction in developing span-new nanozymes and more intelligent strategies for overcoming the current clinical limitations. This article is protected by copyright. All rights reserved.

Analysis of Different Nanostructures of ISFET Biosensors Towards Liposome Detection

Proteins are needed by all living cells for structural and functional purposes. However, some proteins such as liposome instability may result in medication leaks that could harm cells. The detection of liposomes is dependent on the complex interactions between proteins, which are necessary for both their structural integrity and functional characteristics. This emphasizes the critical role that proteins play in the precise identification and examination of liposomal structures. Ion-sensitive field-effect transistor (ISFET) biosensor has gained popularity in the clinical research field for biomolecule detection due to its high detection sensitivity, mass-production capability, and low manufacturing cost. Nanohub BioSensorLab software was used to analyze the performance of different structures of ISFET (planar, cylindrical nanowire, nanosphere and double-gate FET) by simulating the settling time and selectivity of the biosensors. As the structural dimension expands from 1D to 3D, the settling time increases by three folds at the lowest analyte concentration. The fastest settling times were achieved by planar ISFET and double-gate FET. For selectivity measurements, an enhanced selectivity was achieved by increasing the concentration of the target molecule and decreasing the concentration of the parasitic molecule. A higher selectivity is determined by the higher Signal-to-Noise Ratio (SNR) value. The SNR increased linearly corresponds to the increase in the concentration of the target molecule as well as the decrease in the parasitic molecule’s concentration. The parasitic molecule's size increase of 1 nm causes a rise in SNR of 5.00×103.

Emerging adulthood in medical school. Gender, school-related factors and Big Five traits related to medical students’ quarter-life crisis

Background: Quarter-life crisis is the anxiety and discomfort the young might experience at the end of their studies and at the beginning of their career. Objectives: Factors related to medical students’ quarter-life crisis were explored in this study. Methods: in the cross-sectional study, 351 medical students (74.6% female, mean of age: 23.79 years, SD: 1.53 years) filled in the online questionnaire that contained Quarter-life Crisis Questionnaire, International Personality Item Pool version of Big Five markers, and questions about different aspects of medical school. Independent t-test, Mann-Whitney U test and linear regression analysis were performed. Results: Women reported higher quarter-life crisis (t = –3.44, p = 0.001, Cohen’s d = 0.42). Higher quarter-life crisis displayed among those students who did not apply to medical university right after high school (U = 2865.5, p = 0.03, Cohen’s d = 0.24). Students who would have not applied to medical school again (t = –7.93, p &lt; 0.001, Cohen’s d = 0.90); would have not encouraged their children to apply to medical school (U = 10414.5, p &lt; 0.001, Cohen’s d = 0.57); were uncertain to finish university (t = 6.68, p&lt; 0.001, Cohen’s d = 0.74) showed higher quarter-life crisis. Students who failed at least one term for academic reason (U = 11809.5, p = 0.04, Cohen’s d = 0.23); did not feel to get proper knowledge to accomplish a medical job (t = –3.90, p &lt; 0.001, Cohen’s d = 0.54); were not satisfied with their grades (U = 11560.5, p = 0.01, Cohen’s d = 0.27) reported higher quarter-life crisis. Students who did not plan to work in a clinical field and patient care (t =–5.974, p = 0.00, Cohen’s d = 0.93); wanted to work abroad in the future (U = 12931.5, p = 0.00; Cohen’s d =0.27) had higher quarter-life crisis. Personality traits, such as extraversion (β = –0.20, p &lt; 0.001), conscientiousness (β = –0.10, p = 0.01) were significant negative, neuroticism significant positive predictor of quarter-life crisis (β = 0.61, p &lt; 0.001). Conclusion: The explored variables might be indicators of quarter-life crisis, and can be the basis of university counseling, when medical students’ quarter-life crisis and emerging adulthood is in focus.

Accuracy and Clinical Outcomes of Fluoroscopy-Guided and Robotic-Assisted Percutaneous Pedicle Screw Fixation Performed by a Single Surgeon at a Single Center

Objective: Fluoroscopy-guided percutaneous pedicle screw fixation (FGPSF) and its further development, robot-assisted percutaneous pedicle screw fixation (RAPSF), are minimally invasive spinal surgery (MISS) techniques. FGPSF is a standard technique at our hospital, and RAPSF incorporating artificial intelligence has been performed at our hospital since October 2021. This study compared these 2 techniques and analyzed their differences, accuracy, and clinical outcomes based on our experiences.Methods: This study conducted a detailed analysis of screw accuracy and the clinical outcomes of 2 MISS techniques, FGPSF, and RAPSF. Screw accuracy was evaluated using the Gertzbein and Robbins scale, categorizing placements into grades A–E, with grades A and B considered clinically acceptable. Accuracy was assessed using postoperative computed tomography images for FGPSF and intraoperative O-arm scan images for RAPSF. Clinical outcomes were compared by examining parameters, such as hospitalization duration, C-reactive protein (CRP) normalization period, estimated blood loss (EBL), and preoperative/postoperative visual analogue scale (VAS) scores. Screw-related complications were reviewed. Independent image evaluations by nonparticipating spine specialists ensured objective and reliable assessments.Results: Both FGPSF and RAPSF demonstrated high rates of clinically acceptable screw placement, with minimal breaches that required no repositioning. The clinically acceptable rates of FGPSF and RAPSF were similar (99.17% and 99.19%, respectively). Both groups also demonstrated similar clinical outcomes. The CRP normalization period, EBL, and ΔVAS (preoperative—postoperative) scores revealed no statistically significant differences between FGPSF and RAPSF. Neither group experienced screw-related complications; however, the RAPSF group exhibited a statistically significant shorter hospital stay than the FGPSF group.Conclusion: This study compared the accuracy and clinical outcomes of FGPSF and RAPSF. Both methods demonstrated no significant differences in accuracy or clinical outcomes. Spine surgeons selected between the 2 methods based on individual patient needs, and additional research is required to fully understand the practical advantages of each technique in the clinical field.

Rupture of a Previously Unruptured Cerebral Aneurysm 6 Years After Treatment With the Woven EndoBridge (WEB) Device: Case Report

BACKGROUND Introduced to the clinical field in 2011, the Woven EndoBridge (Sequent Medical) device is recognized as a significant innovation for managing wide‐neck bifurcation aneurysms. Delayed aneurysm ruptures, typically occurring hours to months after Woven EndoBridge placement, have been reported. METHODS We present a case of a previously unruptured, known residual aneurysm that ruptured 6 years after treatment with a Woven EndoBridge device. This case underscores the fact that intrasaccular flow diversion, without achieving aneurysm occlusion, does not prevent aneurysm rupture. CONCLUSION Consequently, aneurysm retreatment to attain complete occlusion is imperative.

Precision miRNA profiling: Electrochemiluminescence powered by CRISPR-Cas13a and hybridization chain reaction

The article details a groundbreaking platform for detecting microRNAs (miRNAs), crucial biomolecules involved in gene regulation and linked to various diseases. This innovative platform combines the CRISPR-Cas13a system's precise ability to specifically target and cleave RNA molecules with the amplification capabilities of the hybridization chain reaction (HCR). HCR aids in signal enhancement by creating branched DNA structures. Additionally, the platform employs electrochemiluminescence (ECL) for detection, noted for its high sensitivity and low background noise, making it particularly effective. A key application of this technology is in the detection of miR-17, a biomarker associated with multiple cancer types. It exhibits remarkable detection capabilities, characterized by low detection limits (14.38 aM) and high specificity. Furthermore, the platform's ability to distinguish between similar miRNA sequences and accurately quantify miR-17 in cell lysates underscores its significant potential in clinical and biomedical fields. This combination of precise targeting, signal amplification, and sensitive detection positions the platform as a powerful tool for miRNA analysis in medical diagnostics and research.

Influence of anode/filtration setup on X-ray multimeter energy response in mammography applications

Quality control and assurance of mammography X-ray generators include the use of solid-state detectors and/or ionization chambers calibrated in standard reference radiation fields. The IEC 61267:2005 standard defines reference mammography radiation fields for Mo/Mo anode/filtration, while various anode/filtration combinations are encountered in clinical mammography X-ray units. Not all Secondary Standard Dosimetry Laboratories have an X-ray generator with Mo/Mo radiation setup. Thus, traceability can be established only for the available anode/filter combinations, commonly limited to W/Al. In this study, W/Al radiation fields were established under laboratory conditions by performing half-value layer measurements. Then, four solid-state detectors were characterized. X-ray multimeter performance was evaluated in terms of energy response in the W/Al radiation fields. In the laboratory conditions, the energy response of the dosimeters had a large deviation from unity for dosimeters without appropriate anode/filter combination selected in the software settings, even though most of the dosimeters had a uniform relative response. The discrepancy in the response was further investigated by examining its variation induced by available detector software settings, and it was determined that the dosimeter response can vary up to 20 %. In a clinical setup, the half-value layer was determined, and detector performance was examined. Dosimeters were tested in clinical fields with Mo/Mo, Mo/Rh, W/Rh, W/Ag anode/filter combinations in the X-ray tube voltage range from 25 kV to 35 kV. For most clinical radiation fields, multi-element detectors had energy response deviation within ±5 %. The single-element detector had one software setting available and exhibited strong energy dependence. Extensive testing of detector response, such as presented in this paper. allows for correction factor interpolation based on the half-value layer.

CSF neurofilament light chain profiling and quantitation in neurological diseases.

Neurofilament light chain is an established marker of neuroaxonal injury that is elevated in CSF and blood across various neurological diseases. It is increasingly used in clinical practice to aid diagnosis and monitor progression and as an outcome measure to assess safety and efficacy of disease-modifying therapies across the clinical translational neuroscience field. Quantitative methods for neurofilament light chain in human biofluids have relied on immunoassays, which have limited capacity to describe the structure of the protein in CSF and how this might vary in different neurodegenerative diseases. In this study, we characterized and quantified neurofilament light chain species in CSF across neurodegenerative and neuroinflammatory diseases and healthy controls using targeted mass spectrometry. We show that the quantitative immunoprecipitation-tandem mass spectrometry method developed in this study strongly correlates to single-molecule array measurements in CSF across the broad spectrum of neurodegenerative diseases and was replicable across mass spectrometry methods and centres. In summary, we have created an accurate and cost-effective assay for measuring a key biomarker in translational neuroscience research and clinical practice, which can be easily multiplexed and translated into clinical laboratories for the screening and monitoring of neurodegenerative disease or acute brain injury.