Increasing the Level of Neopterin in patients infected with SARS-CoV-2 Indicates Fatal Mortality

Background: The severity of Coronavirus Disease-2019 (COVID-19) cases is associated with hyperinflammation. Patients with critical and severe COVID-19 have been observed to have high amounts of circulating cytokines. Neopterin, a crucial cytokine in the antiviral immune response that is released by macrophages upon stimulation with interferon-gamma, can be utilized to forecast the severity of illness in COVID-19 patients. Methods: The study included 185 patients with COVID-19. The patients with COVID-19 were divided into three groups according to disease severity as critical disease (n=51), severe disease (n=81), and moderate disease (n=53). All basic demographic and clinical data of the patients were recorded and blood samples were collected. Results: Neopterin levels were significantly higher in critical COVID-19 patients compared with severe and moderate COVID-19 patients (p < 0.0001). Further, neopterin showed significantly higher levels in the age group >50 years of patients with COVID-19 than in the age group <50 years. Neopterin levels were correlated with WBCs, Platelet, CRP, D-Dimer, Ferritin, Fibrinogen, IL-6, and Procalcitonin levels positively (ρ= 0.569, 0.474, 0.338, 0.696, 0.605, 0.77, 0.727, and 0.585;p < 0.01 respectively), and correlated with BMI, SpO2, and lymphocyte negatively (ρ= - 0.165;p < 0.05, p= - 0.754, - 0. 548;p < 0.01 respectively). A cutoff value of 23.62 nmol/L for neopterin predicted COVID-19 with a sensitivity of 95.7% and a specificity of 95.5% (AUC: 0.986;p < 0.0001). Conclusion: Neopterin may be a useful prognostic biomarker for assessing the severity of COVID-19.

Nutritional Status of Slovene Adults in the Post-COVID-19 Epidemic Period.

Background: Monitoring nutritional status data in the adult population is extremely important to mediate their health status. Unfortunately, for Slovenia (2.1 million European Union citizens), data on the body composition status of the general adult population are currently rare or nonexistent in scientific journals. Furthermore, dietary intake was last assessed several years before the COVID-19 epidemic period. Methods: We randomly recruited 844 adult Slovenes from all regions of Slovenia. The primary aim of the cross-sectional study was to examine body composition status (using a medically approved electrical bioimpedance monitor) during the post-COVID-19 epidemic period. In addition, we assessed dietary intake (using a standardized food frequency questionnaire) and compared the obesity propensity for both sexes separately using the body mass index (BMI) and body fat percentage (FAT%) obesity classification of the World Health Organization. Results: Regarding BMI classification, 43% of the whole sample was overweight (28%) or obese (15%), and there were more older adults than adults (64% vs. 42%, p < 0.001). The average FAT% of adult females and males was 26.9% and 19.5% (p < 0.001), respectively, while for older adult females and males, it was 32.7% and 23% (p < 0.001). In addition, a comparison of the proportions of obese people between the two cut-off obesity classifications (BMI vs. FAT%) showed a significantly underestimated proportion of obese female participants based on BMI classification (13% vs. 17%, p = 0.005). In terms of the dietary intake of the assessed nutrients in comparison with the national dietary reference values for energy and nutrient intake, the participants, on average, had lower intake than the recommended values for carbohydrates, fiber, vitamins C, D and E (for males) and calcium, and higher intake than the recommended values for total fat, saturated fatty acids, cholesterol, sodium and chloride (for males). Conclusions: The results urgently call for the need to not only improve the overall national nutritional status but also for regular national monitoring of body composition and dietary intake statuses.

EURAMET.EM-S44 "Comparison for Ultra-low DC Current Sources

The EURAMET.EM-S44 comparison was performed with 7 participants. The objective of this comparison is to provide technical evidence supporting their CMCs entries of those participants who did not participate in the EURAMET.EM-S24, while other participants would have an evidence for confirmation of their improvements in this field of measurement. Besides, ±9.5 fA measurements measurements have been performed in addition to the measurement points of EURAMET.EM-S24. A commercial electrometer Keithley 6430 was used as travelling standard. A linear drift of the travelling standard was observed at ±95 pA, ±9.5 pA and ±0.95 pA values.Therefore, the effect of the linear drift was eliminated for the evalution of the measurement results. The comparison reference value has been determined based on the weighted mean of participant results that survived outlier detection. The discarded results have been showed in the tables in "Measurement Results" section. Because of the Covid-19 pandemic conditions, some delays in customs and in sending the participants reports, the comparison has taken longer time period than expected. © 2023 Institute of Physics Publishing. All rights reserved.

Automatic Health Monitoring In Health Estate

This paper proposes an automatic system to monitor the health status of the individuals in an estate such as their blood pressure values, their blood glucose value, their blood oxygen value, their heart rate and their respiratory rate. In particular, the system consists of an intelligent watch, a mobile application, a central server and a medical platform. The intelligent watch acquires five photoplethysmograms (PPGs) via different photo sensors with different wavelengths and transmits the PPGs to the mobile via a bluetooth transmitter. The mobile application allows the inputs of the reference values of these health indices of the individuals and displays the estimated values. Also, it sends the PPGs and these reference values to the central server. The central server estimates the health indices. The medical platform consists of a team of medical officers. They monitor the health indices of the individuals and provide the medical advices. This system can detect the occurrence of the sudden decay of the health status of the individuals. Hence, it can reduce the death rate due to the spread of the new diseases such as the COVID19. © 2022 IEEE.

Age- and Sex-Specific Physical Fitness Reference and Association with Body Mass Index in Hong Kong Chinese Schoolchildren.

There is lacking a population-based study on the fitness level of Hong Kong schoolchildren, and it seems that increasing childhood obesity prevalence has shifted the classification of healthy fitness, with 'underfit' as normal. This cross-sectional territory study aimed to develop an age- and sex-specific physical fitness reference using a representative sample of children aged 6-17 and to determine the associations with body mass index in schoolchildren. The study analyzed Hong Kong School Physical Fitness Award Scheme data covering grade 1 to grade 12 students' physical fitness and anthropometric measurements from 2017 to 2018. This reference was established without the impact due to COVID-19. Four aspects of physical fitness tests were measured using a standardized protocol, including (i) upper limb muscle strength, (ii) one-minute sit-up, (iii) sit-and-reach, and (iv) endurance run tests. The generalized additive model for location, scale, and shape was used to construct the reference charts. A Mann-Whitney U test was used to compare the mean differences in age, weight, and height, and a Pearson's chi-square test was used to examine the distributions of sex groups. A Kruskal-Wallis test was used to compare the group differences in BMI status, followed by the Dunn test for pairwise comparisons. A 5% level of significance was regarded as statistically significant. Data of 119,693 students before the COVID-19 pandemic were included in the analysis. The association between physical fitness level and BMI status varied depending on the test used, and there were significant differences in fitness test scores among BMI groups. The mean test scores of the obese group were lower in most of the tests for both boys and girls, except for handgrip strength. The underweight group outperformed the obese group in push-ups, one-minute sit-ups, and endurance run tests, but not in handgrip strength. In conclusion, a sex- and age-specific physical fitness reference value for Hong Kong Chinese children aged 6 to 17 years old is established, and this study demonstrated a nonlinear relationship between BMI status and physical fitness. The reference will help to identify children with poor physical fitness to offer support and guidance on exercise training. It also serves as a baseline for assessing the impact of the COVID-19 pandemic on Hong Kong students' physical fitness.

Kynurenine serves as useful biomarker in acute, Long- and Post-COVID-19 diagnostics.

Introduction: In patients with SARS-CoV-2, innate immunity is playing a central role, depicted by hyperinflammation and longer lasting inflammatory response. Reliable inflammatory markers that cover both acute and long-lasting COVID-19 monitoring are still lacking. Thus, we investigated one specific inflammatory marker involved as one key player of the immune system, kynurenine (Kyn), and its use for diagnosis/detection of the Long-/Post-COVID syndrome in comparison to currently used markers in both serum and saliva samples. Material and methods: The study compromised in total 151 inpatients with a SARS-CoV-2 infection hospitalized between 03/2020 and 09/2021. The group NC (normal controls) included blood bank donors (n=302, 144f/158m, mean age 47.1 ± 18.3 years (range 18-75)). Two further groups were generated based on Group A (n=85, 27f/58m, mean age 63.1 ± 18.3 years (range 19-90), acute admission to the hospital) and Group B (n=66, 22f/44m, mean age 66.6 ± 17.6 years (range 17-90), admitted either for weaning or for rehabilitation period due to Long-COVID symptoms/syndrome). Plasma concentrations of Kyn, C-Reactive Protein (CRP) and interleukin-6 (IL-6) were measured on admission. In Group B we determined Kyn 4 weeks after the negative PCR-test. In a subset of patients (n=11) concentrations of Kyn and CRP were measured in sera and saliva two, three and four months after dismission. We identified 12 patients with Post-COVID symptoms >20 weeks with still significant elevated Kyn-levels. Results: Mean values for NC used as reference were 2.79 ± 0.61 µM, range 1.2-4.1 µM. On admission, patients showed significantly higher concentrations of Kyn compared to NC (p-values < 0.001). Kyn significantly correlated with IL-6 peak-values (r=0.411; p-values <0.001) and CRP (r=0.488, p-values<0.001). Kyn values in Group B (Long-/Post-COVID) showed still significant higher values (8.77 ± 1.72 µM, range 5.5-16.6 µM), whereas CRP values in Group B were in the normal range. Conclusion: Serum and saliva Kyn are reflecting the acute and long-term pathophysiology of the SARS-CoV-2 disease concerning the innate immune response and thus may serve a useful biomarker for diagnosis and monitoring both Long- and Post-COVID syndrome and its therapy.

A FLOW CYTOMETRIC EVALUATION OF B LYMPHOCYTE CELLS AND SUBGROUPS OF CHILDREN DIAGNOSED WITH COVID-19

Objective: During viral infections, antibody production of B cells are critical for protective immunity. It is known that the COVID-19 disease has a milder course in children. It is crucial to evaluate the causes of this situation from a pediatrician's perspective to determine the treatment goals of the disease. We aimed to examine the flow cytometric changes in B cells and subtypes observed in children diagnosed with the COVID-19 infection. Materials and Methods: This is a prospective cohort study including 22 children aged 0-18 who had been diagnosed with COVID-19. CD19(+)B cells, CD27(-)IgD(+) naive B, CD21(low )immature B, CD21(low)CD38(low) active B, CD27(-)IgD(-) double-negative B, CD27(-) non-memory B, CD27(+) memory B, CD27(+)IgD(-) switched memory B, and CD27(+)IgD(+) non-switched memory B cells were studied using flow cytometry. Results: B cells counts decreased as a percentage in the 2-5 years age group and the 10-16 age group as an absolute number. Naive and non-memory B cell frequencies increased in the 5-10 years old and over 16 years old groups. Double negative B cells were normal in all age groups. Non-memory B cells increased in the 5-10 and over 16 years old groups, whereas memory B cells decreased. In all groups, switched memory B cells decreased. Non-switched memory B cell counts were within reference ranges in all groups except for the over 16 years group. Conclusion: Although the decrease in B cell count is associated with the severity of the disease, naive B cell subgroups did not decrease in the pediatric patients included in the study. All groups showed increased switched memory B cell counts, in accordance with the literature. Unlike adults, naive B cells, non-switched memory B cells, and double-negative B cells were normal in children.

Performance Evaluation of Infrared Thermal Sensors based on Distance, Room Temperature, and Physical Activity on Objects

Fever has a sensitivity of 54% and specificity of 67% against SARS-CoV-2 so it can be used to determine whether a person is infected with COVID-19. To prevent the spread of the virus in public places, a body temperature screening process using an infrared thermometer is required. The two sensors that are commonly used as infrared thermometers are the MLX90614 and AMG8833 because of their high temperature range and good accuracy. However, the measurement results can be affected by the measuring distance, room temperature, and physical activity in the human body. Therefore, an infrared thermometer with two sensors arranged in overlay was designed to evaluate the performance of infrared thermal sensors based on measuring distances (15, 30, 40, and 60 cm), 2 rooms (26.4 oC and 30 oC), and physical activity on the object. The results in the 30 oC room at 15 – 40 cm show measured temperature above 36 oC for both sensors, while in the 26.4 oC room it decreased up to 35.32 oC. At 15 cm in a 26.4 oC room, the measured temperature results are the closest to the reference values with a difference of less than 0.3 oC for the MLX90614 sensor, while at 60 cm, the results are the furthest from the reference values also it has larger difference value, which is 0.21 oC for the MLX90614 and 1.01 oC for the AMG8833. In conclusion, the MLX90614 sensor is better than the AMG8833 sensor because its outputs are closer to the reference values. ©2021 IEEE

Receiver operating characteristic curve: overview and practical use for clinicians.

Using diagnostic testing to determine the presence or absence of a disease is essential in clinical practice. In many cases, test results are obtained as continuous values and require a process of conversion and interpretation and into a dichotomous form to determine the presence of a disease. The primary method used for this process is the receiver operating characteristic (ROC) curve. The ROC curve is used to assess the overall diagnostic performance of a test and to compare the performance of two or more diagnostic tests. It is also used to select an optimal cut-off value for determining the presence or absence of a disease. Although clinicians who do not have expertise in statistics do not need to understand both the complex mathematical equation and the analytic process of ROC curves, understanding the core concepts of the ROC curve analysis is a prerequisite for the proper use and interpretation of the ROC curve. This review describes the basic concepts for the correct use and interpretation of the ROC curve, including parametric/nonparametric ROC curves, the meaning of the area under the ROC curve (AUC), the partial AUC, methods for selecting the best cut-off value, and the statistical software to use for ROC curve analyses.