Enzyme-linked Immunoassay Method Research Articles

Urinary cyclophilin A as an early marker of chronic kidney disease with underlying type 2 diabetes

Cyclophilin A (CypA) is a novel renal inflammation biomarker, with levels altered in various diseases, particularly in patients with diabetes mellitus (DM) and kidney damage. This study aimed to investigate the correlation between urinary cyclophilin A (uCypA) and chronic kidney disease (CKD) conditions with and without type 2 diabetes mellitus (T2DM) using an in-house enzyme-linked immunoassay (ELISA) method. A uCypA strip-test prototype was also developed. An indirect ELISA was performed to determine the uCypA levels. A 0.48 µg/mL uCypA cutoff differentiated healthy patients from those with early-stage CKD (stages I and II). The uCypA levels were significantly increased in patients with progression of renal deterioration, especially in the T2DM with late-stage CKD group, compared to the control group. Fasting blood sugar (FBS), estimated glomerular filtration rate (eGFR), albumin/creatinine ratio, and metformin use were associated with uCypA levels. Multinomial logistic regression analysis revealed an association between uCypA levels and T2DM diagnosed for over five years and early-stage CKD. This finding shows that uCypA could be used as a biomarker for distinguishing early-stage CKD as well as T2DM complications, which is beneficial for patients to be aware of their health status and change their behavior to slow kidney deterioration.

Are Sirtuins 1 and 2 Relevant Players in Relapsing-Remitting Multiple Sclerosis?

A total of 115 patients with RRMS (78 women, 37 men, mean age 43 ± 9.9) and 39 healthy controls were included in the study. SIRT1 and SIRT2 were detected in the serum using the enzyme-linked immunoassay (ELISA) method. In the RRMS group, relationships were investigated between the SIRT 1 and 2 levels and the demographic data, MS-related clinical variables, and the results of tests evaluating fatigue, sleep problems, cognitive performance, autonomic dysfunction, and depression. The levels of SIRT1 and SIRT2 in RRMS patients were significantly lower than in the controls (11.14 vs. 14. 23, p = 0.04; 8.62 vs. 14.2, p < 0.01). In the RRMS group, the level of both SIRTs was higher in men than in women (15.7 vs. 9.0; 11.3 vs. 7.3, p = 0.002) and showed a significant correlation with the degree of disability (R = -0.25, p = 0.018). No other relationships were found between SIRT levels and the analyzed data. The serum levels of SIRT1 and 2 were decreased in the RRMS patients (especially in the female ones) and correlated with the degree of neurological deficit. The role of SIRTs as biomarkers of disease activity or mediators relevant for "invisible disability" in MS warrants further investigation.

Direct competitive immunoassay method for sensitive detection of the histamine in foods based on a MI-Cu-GMP nanozyme marker and molecularly imprinted biomimetic antibody.

Histamine may lead to low blood pressure, skin flushing and edema when it accumulates in large amounts in the body. Therefore, establishing sensitive methods for the detection of histamine in foods is extremely important to ensure food safety and human health. The MI-Cu-GMP NPs (2-methylimidazole-copper-guanosine monophosphate nanozymes) with high laccase-like activity were synthesized. Using the prepared molecular imprinted membrane as biomimetic antibody and MI-Cu-GMP NPs as marker, a sensitive direct competitive biomimetic enzyme-linked immunoassay (BELISA) method for rapid detection of the histamine in foods was developed. Under optimal conditions, the limit of detection (LOD, IC15) and sensitivity (IC50) of the BELISA method for histamine was 0.05 mg L-1 and 1.22 mg L-1, respectively. The liquor samples spiked with histamine was detected by the BELISA method with satisfactory recoveries ranging from 90.00% to 116.00%. Further, the level of histamine in three samples (cooking wine, rice vinegar and soy sauce) was tested by the BELISA and high-performance liquid chromatography (HPLC), with no significant difference found between the two methods. Given the advantages, the established BELISA method is expected to provide practical guidance for the monitoring of histamine in food and provides a foundation for the detection of other food hazards. © 2024 Society of Chemical Industry.

Exploring the Association between Depression, Suicidality, and Serum Brain-Derived Neurotrophic Factor, FAM19A5, Total Antioxidant Status, Total Oxidant Status, Oxidative Stress Index, and Cytokine Levels: A Case-Control Study of Drug-Naive Adolescents with First-Episode Major Depressive Disorder

Introduction: Considering the importance of neuroinflammation and neurodegeneration in the pathophysiology of major depressive disorder (MDD), peripheral blood biomarkers are promising for the prediction of diagnosis and treatment outcomes. We aimed to elucidate the neuroinflammatory pathophysiology of depression by evaluating serum levels of FAM19A5 as a new biomarker of inflammatory activation, proinflammatory cytokines, brain-derived neurotrophic factor (BDNF), and oxidative stress parameters. Methods: Adolescents diagnosed with first-episode drug-naive MDD (n = 35) were compared neurobiologically healthy control group (n = 33). Serum FAM19A5 levels, cytokine levels, BDNF and oxidative stress parameters were evaluated using the enzyme-linked immunoassay method. All participants were assessed with the Level-2 Depression Severity Scale, Sleep Disturbance Scale, Somatic Symptom Scale. Results: BDNF levels were significantly higher in the patient group compared to the control group. While BDNF showed a positive correlation with all scale scores; BDNF was significantly higher in the suicide risk groups than the control group. IL-1β levels displayed a negative correlation with the severity of sleep disturbances. Conclusions: In adolescents with MDD, inflammatory and oxidative stress markers were not raised in peripheral blood, unlike in adults. However, BDNF levels, which typically decrease in neurodegenerative conditions, were higher in those with MDD.

Effects of N-Acetylcysteine on Humanin and Endostatin in Rats Exposed to Formaldehyde.

People are constantly exposed to formaldehyde, a volatile and poisonous gas, in indoor environments. In particular, anatomists, pathologists, histologists, and those involved in embalming are exposed to higher amounts of formaldehyde continuously due to their work. This study aimed to investigate the effect of N-acetylcysteine on endostatin and humanin values in male rats exposed to experimental formaldehyde. In the study, 28 male Spraque-Dawley rats aged 12-14 weeks (seven animals in each group: control group, formaldehyde group, N-acetylcysteine group, formaldehyde+N-acetylcysteine group) were used. Four weeks later, the animals were sacrificed by decapitation. Following decapitation, endostatin and humanin levels in the serum of rats were studied by the enzyme-linked immunoassay (ELISA) method. In all analyses, p<0.05 was accepted as statistically significant. Humanin and endostatin values were checked in the serum of rats. When humanin levels were compared between groups, a statistically significant difference was found between the formaldehyde group and both the control group (p<0.05) and the N-acetylcysteine group (p<0.05). In the formaldehyde+N-acetylcysteine group, it was determined that the humanin level was impaired due to formaldehyde exposure, approaching the control group values with the administered N-acetylcysteine. When the endostatin level was compared between the groups, a statistical significance (p<0.05) was found only between the formaldehyde group and the N-acetylcysteine group. In the formaldehyde+N-acetylcysteine group, it was determined that the endostatin level was impaired due to formaldehyde exposure, approaching the control group values with the administered N-acetylcysteine. In this study, the effects of N-acetylcysteine on humanin and endostatin on rats exposed to formaldehyde were demonstrated for the first time. Formaldehyde exposure negatively affected humanin and endostatin levels in rat sera. N-acetylcysteine ameliorated the negative effects of formaldehyde, bringing humanin and endostatin levels closer to the healthy control group.

Combination of distance-based paper analytical devices with ionic liquid-based dispersive liquid-liquid microextraction for enzyme-free bilirubin quantification

This article introduces the first demonstration of integrating distance-based paper analytical devices (dPADs) with ionic liquid-based dispersive liquid-liquid microextraction (IL-DLLME) for the quantitative detection of bilirubin levels in human samples. In this approach, bilirubin is preconcentrated and extracted into a small droplet of the extraction solvent using IL-DLLME. The resulting solution is then introduced into an economical and straightforward dPAD sensor. Detection relies on a colorimetric reaction between bilirubin and gold ions (Au3+), leading to the in-situ formation of gold nanoparticles (AuNPs) on the paper substrate. The observed red-purple distance length is directly proportional to the bilirubin level. Under optimization, a linear range between 0.25 nM and 5.0 nM (R2 = 0.9979) and a detection limit (LOD) of 250.0 pM were achieved. The assay exhibits notable precision and selectivity without any interference. With its distance readout feature, this method is simpler and more cost-effective, offering greater sensitivity compared to other methods requiring expensive reagents and instruments. Moreover, the technique shows high accuracy and precision for bilirubin quantification in human control samples, with recoveries ranging from 98.33% to 102.00%. No significant difference was observed between our method and the enzyme-linked immunoassay (ELISA) method. By combining a low-cost microfluidic device with a simple microextraction method, this strategy holds great potential as an alternative analytical method for determining bilirubin. It can be expanded for further applications in analytical sensing for point-of-care (POC) diagnostics.

Chronic Unpredictable Mild Stress Affects Weight Changes Through Circadian Cycle Mechanism

Everyday stress is unpredictable and comes in many different forms. The person is constantly exposed to stress because they cannot handle it. Chronic stress results from this illness. Chronic stress can affect changes in the body's standard mechanisms, including body weight modulated by the circadian cycle. Due to the fact that each person's response to stress is unique, stressful situations might result in two different variations in body weight. The purpose of this study is tobserve the effect of the CUMS on weight changes in Rattus novergicus through the circadian cycle mechanism. 16 chronic stress models of the Rattus norergicus were split into control and treatment groups. The chronic stress was provided using the Chronic Unpredictable Mild Stress (CUMS) approach. The control group did not receive any treatment but was still given maintenance such as providing food, drink and measuring their body weight every day. While the treatment group received CUMs for 20 days. Every morning before the stressor exposure, body weight was recorded. And the measurement of corticosterone levels using the Enzyme-Linked Immunoassay (ELISA) method with the Duplo technique. Before termination, blood is taken at the heart. Corticosterone levels varied across the groups (p = 0.032). The study's changes in body weight (p = 0.00) revealed a difference between the control and treatment groups, with the treatment group's weight being -11.15 ± 7.91. Chronic stress can alter how the body normally functions, mainly how the circadian cycle regulates body weight. Since each person's response to stress is unique, stressful situations might result in two different variations in body weight.

Faecal glucocorticoid analysis as indicator of stress and its effect on the reproduction hormones of the female Malayan sun bear (Helarctus malayanus) in captivity.

Faecal glucocorticoid metabolite (FGM) is frequently used as a non-invasive tool to assess adrenocortical activity in animal conservation and welfare studies. However, studies assessing the stress level and its effect on the reproductive hormones of female Malayan sun bear is lacking. This study aims to assess the level of stress of the female Malayan sun bear in captivity and its effect on the female reproductive hormones of the female Malayan sun bears in captivity in Malaysian Borneo. Through FGM analysis via the enzyme-linked immunoassay (ELISA) method, it was found that the bear living in BSBCC has the lowest level of glucocorticoid. as for the relationship between the level of stress and the female reproductive hormones, the level of estrogen which was indicated by estradiol, decreases as the level of FGM increases. In contrast, the level of progesterone increase as the level of FGM increases. It can be concluded that the level of stress in captivity could affect the level of estrogen and progesterone and a high level of progesterone does not always indicate a good reproductive function in female mammals.

Examination of empathy-like behaviour in nicotine-preferring rat lines

Aim Addiction is an important global health issue, impacting also addicts environment and society. Empathy plays crucial role in establishing successful social relationships and is a fundamental component of social life. The aim of this study is to investigate how nicotine preferring (NP) strain and oral forced nicotine administration affects empathy-like behaviour in rats, with gender differences. Materials and Methods Sprague-Dawley NP rats (10 males/10 females) and wild-type control rats (10 males/10 females) were used. Behavioural tests were administered to all rats before and after oral forced nicotine administration. The behavioural tests were completed in the fourth week of nicotine administration. Anxiety levels that could affect empathy-like behaviour were evaluated with open field, elevated plus maze tests and with blood cortisol levels. Oxytocin receptor and arginine vasopressin (AVP) levels, which have been shown to be related to empathy-like behaviour, were examined in the prefrontal cortex and amygdala regions using the enzyme-linked immunoassay method. Results It was observed that males from the NP strain showed less empathy-like behaviour than all other groups, and nicotine administration did not cause a significant change in the results. Higher levels of locomotor activity (LA) were found in control females than in all other groups. Blood nicotine and corticosterone levels were higher in NP rats. No significant differences were found in AVP and oxytocin receptor levels in the prefrontal cortex and amygdala. Conclusions It was found that coming from an addicted strain particularly reduces empathy-like behaviour in males.

High urine sodium/potassium ratio, high LDL/HDL ratio, high level of serum F2-isoprostane, and low level of microtubule-associated protein 1a/1b-light chain 3b (LC3B) as risk factors of preeclampsia

Background: Preeclampsia (PE), still a major health concern which is related to high maternal mortality and morbidity rates. It is historically correlated with early oxidative stress and autophagy dysfunction, prompting this study to investigate the potential risk factors of PE, including high level of urine sodium/potassium (Na/K) ratio, low-density lipoprotein to high-density lipoprotein (LDL/HDL) ratio, elevated serum F2-Isoprostane levels (F2-IsoPS), and diminished serum microtubule-associated protein 1a/1b-light chain 3b (LC3B). Methods: This is a case-control study, conducted at Prof. Dr. I.G.N.G Ngoerah General Hospital from June to September 2023, including 25 pregnant women with preeclampsia (PE) as cases and 25 without PE as controls. The study analyses urine sodium and potassium levels, serum LDL and HDL levels, LC3B, and F2-isoprostane levels using the Enzyme-linked Immunoassay (ELISA) method. Statistical analysis was conducted using IBM SPSS Statistics Version 25 software. Results: High urine sodium/potassium ratio (&gt;3.95), high serum LDL/HDL Ratio (&gt;2.6), high serum F2-Isoprostane levels (&gt;476.24 ng/mL), and low serum LC3B levels (&lt;291.975 ng.mL) was found to be a significant risk factor for preeclampsia, with an OR of 11.16 (p &lt; 0.001; 95% CI = 2.86 – 43.46); OR= 23.222 (p &lt; 0.001; 95% CI = 5.101 – 105.728); OR= 38.5 (p=0.000; 95% CI: 7.681-192.985); and OR=8.143 (p=0.001; 95% CI: 2.294-28.901) respectively. Based on multivariate analysis, the variables that contribute mainly to the occurrence of PE, from the highest, respectively, are high LDL/HDL ratio, high level of F2-IsoPs, low level of serum LC3B, and high urine Na/K ratio (OR=149.96; OR=95.43; OR=36.11; and OR=12.71). Conclusion: High LDL/HDL ratio, high level of F2-Isoprostanes serum, low level of serum LC3B, and high urine Na/K ratio are risk factors for preeclampsia.

Performa Rapid Diagnostik Tes Hepatitis B dengan ELISA sebagai Gold Standar

The ELISA (Enzyme Linked Immunoassay) method has high sensitivity and specificity, qualitatively and quantitatively detecting Hepatitis B Surface Antigen (HBsAg) levels, but the process is long, expensive and requires special expertise, compared to the Rapid Diagnostic Test (RDT) as a rapid test which is more practical and cheaper. The aim of this study was to compare the sensitivity and specificity of the Entebe Rapid Test Diagnostic (ERTD) produced by PT. Hepatika Mataram, with ELISA as the gold standard in detecting HBsAg. The requirement for interpreting sensitivity and specificity results according to World Health Organization (WHO) standards is a minimum of 95%. Testing with a negative panel of 00 samples and a positive panel of 1 samples from Papua in 012 at -80℃ storage. Testing in April 023 at the Molecular Diagnostics and Research Laboratory, Mataram University Hospital. Statistical analysis using MedCal software. ERD HBsAg produced by PT. Hepatika Mataram has a sensitivity of 95.45%, specificity of 99.50%, positive predictive value of 93.59%, negative predictive value of 99.65%, and accuracy of 99.21%.

Differences of Hepatitis B Serological Tests in Cirrhosis and Hepatocellular Carcinoma Patients

Cirrhosis and hepatocellular carcinoma (HCC) are the most common complications of chronic hepatitis B. Hepatitis B Virus (HBV) reactivation occurs in the inactive phase, characterized by reappearance of HBsAg or negative HBsAg. The prevalence of occult hepatitis B infection in cirrhosis and HCC ranges from 20% to 60%. This study aimed to analyze the differences in hepatitis B serological tests in patients with cirrhosis and HCC for diagnosis of acute or chronic hepatitis B. The current research was analytical and descriptive with a cross-sectional study design. This study involved 177 patients, including 50 cirrhosis patients and 127 HCC patients. Hepatitis B serological tests (HBsAg, HBeAg, anti-HBe, total anti-HBc) were analyzed using VIDAS instruments by the Enzyme-Linked Fluorescent Immunoassay (ELFA) method. Hepatitis B serological test results were grouped based on the interpretation of serological test results. The data were processed with the statistical test Kolmogorov-Smirnov test, independent T-test, and Chi-Square, and results with p&lt;0.05 were reported as significant. This study found that most males suffer from cirrhosis and HCC due to chronic HBV infection, with a mean age of 57. Chronic hepatitis was most common in patients with cirrhosis and HCC (71.2%). There was no significant difference in the interpretation of the hepatitis B serological test between patients with cirrhosis and HCC, with a p-value of 0.230 (p &gt; 0.05). There was no significant difference in interpreting the hepatitis B serological test between cirrhosis and HCC. Both reactive HBsAg and non-reactive HBsAg can be obtained in cirrhosis and HCC.

Aflatoxins and Ochratoxin A in Tea Sold in Lebanon: Effects of Type, Packaging, and Origin.

Tea is among the oldest and most-known beverages around the world, and it has many flavors and types. Tea can be easily contaminated in any of its production steps, especially with mycotoxins that are produced particularly in humid and warm environments. This study aims to examine the level of ochratoxin A (OTA) and total aflatoxin (AF) contamination in black and green tea sold in Lebanon, evaluate its safety compared to international standards, and assess the effect of different variables on the levels of OTA and AFs. For this, the Lebanese market was screened and all tea brands (n = 37; 24 black and 13 green) were collected twice. The Enzyme-Linked Immunoassay (ELISA) method was used to determine OTA and AFs in the samples. AFs and OTA were detected in 28 (75.7%) and 31 (88.6%) samples, respectively. The average of AFs in the positive (above detection limit: 1.75 μg/kg) samples was 2.66 ± 0.15 μg/kg, while the average of OTA in the positive (above detection limit: 1.6 μg/kg) samples was 3.74 ± 0.72 μg/kg. The mean AFs in black and green tea were 2.65 ± 0.55 and 2.54 ± 0.40 μg/kg, respectively, while for OTA, the mean levels were 3.67 ± 0.96 and 3.46 ± 1.09 μg/kg in black and green tea samples, respectively. Four brands (10.8%) contained total aflatoxin levels above the EU limit (4 μg/kg). As for OTA, all samples had OTA levels below the Chinese limit (5 μg/kg). No significant association (p > 0.05) was found between OTA and tea type, level of packaging, country of origin, country of packing, and country of distribution. However, AF contamination was significantly (p < 0.05) higher in unpacked tea, and in brands where the country of origin, packing, and distributor was in Asia. The results showed that the tea brands in Lebanon are relatively safe in terms of AFs and OTA.

Kruppel benzeri faktör 2 polimorfizmlerinin koroner arter hastalığı riski ile ilişkisi

Purpose: Coronary artery disease is defined as complications that develop in proportion to the prevalence of ischemia due to occlusion of the coronary arteries and the resulting cell death. The development of atherosclerosis is significantly influenced by endothelial cell dysfunction. Kruppel-like factor 2, a transcription factor, has been shown to regulate critical biological events in endothelial biology, such as vascular tone, migration, proliferation, vasoreactivity, and angiogenesis. In our study, it was aimed to clarify the relationship between coronary artery disease and Kruppel-like factor 2 protein levels and C1239A polymorphisms.&#x0D; Materials and Methods: 191 individuals who underwent coronary angiography at Mersin University Faculty of Medicine, Department of Cardiology, Health, Research and Application Center were included in the study. Measurements of serum fasting blood glucose, HDL cholesterol, total cholesterol, and triglyceride levels were performed on the AU5800 (Beckman Coulter, United States) autoanalyzer. Serum LDL levels were calculated using the Friedwald equation. Serum Kruppel-like factor 2 protein levels were measured by sandwich enzyme-linked immunoassay method on the Multiskan GO (Thermo Scientific, Finland) device. Kruppel-like factor 2 C1239A variations were detected on the Applied Biosystem VIIA™ 7 Real-Time PCR (Life Technologies Co., United States) device by TaqMan® single nucleotide polymorphism (SNP) genotyping method.&#x0D; Results: Men had a 3.8-fold higher risk of CAD than women. (Odd’s ratio 3.83, 95% Confidence interval 1.98-7.39; p

EFFECTS OF DHIKR ON SPIRITUALITY AND CORTISOL LEVELS AMONG PATIENTS WITH HEART FAILURE: A PILOT STUDY

Introduction: Depression and anxiety are common comorbid conditions in patients with heart failure (HF). Spirituality was found to have a positive impact on patients’ mental health status. However, whether the spiritual practice affects physiological modulation is still questionable. Therefore, this study aimed to analyze the effect of dhikr as spiritual practice on spirituality and cortisol levels among patients with HF. Methods: A quasi-experiment was used in this study. A sample size of 18 respondents consists of 9 respondents of the control group and 9 respondents of the treatment group. Dhikr intervention was conducted in three meetings with an interval of two days during patients’ hospitalization. Spirituality was measured using a spirituality questionnaire, whereas the cortisol levels with venous blood sampling, measured by the enzyme-linked fluorescent immunoassay (ELFA) method. Statistics analysis in this study was using t-Test for spirituality, Mann Whitney and Wilcoxon Sign Rank Test for cortisol level with a significance level of α&lt;0.05. Results: The results showed that dhikr improves the spirituality of HF patients (p=0.000) and decreases the level of cortisol (p=0.015) significantly. Dhikr interventions appears to strengthen spirituality in patients with HF by improving stress perception which further modulates the adaptive stress response in the form of decreasing cortisol levels. Conclusions: Dhikr could be one of the spiritual nursing interventions to improve spirituality and stress hormonal modulation in patients with HF.

Association between bacterial vaginosis and 25-Hydroxy vitamin D: a case-control study

IntroductionBacterial vaginosis (BV) is the most common vaginal dysbiosis among women of reproductive age. Micronutrient deficiencies, including vitamin D deficiency, can increase the risk of BV. The findings of previous studies regarding the relationship between vitamin D deficiency and BV were conflicting. Therefore, this study aimed to evaluate the association between BV and serum level of 25-hydroxy vitamin D.Materials and methodsThis case-control study was conducted in Gonabad County in 2021. One hundred and twenty-five confirmed BV cases and 125 controls who were matched based on age and intercourse frequency (maximum difference of two days per week) enrolled in the study. Data collection was performed using a demographic and reproductive data questionnaire and a checklist for recording Whiff test results, serum 25-hydroxy vitamin D level, litmus paper observation, and microscopic findings (clue cells). Serum level of vitamin D was evaluated based on enzyme-linked immunoassay method (Monobind kit) from 0.5 ml venous blood drawn from each participant. The conditional logistic regression model was used to analyze data.ResultsThe BV cases had significantly lower 25-hydroxy vitamin D serum levels than controls. The odds of BV increased with vitamin D deficiency (Adjusted odds ratio (AOR): 4.34, 95% confidence interval (CI): 1.39–13.4, p = 0.011, FDR q-value = 0.051), vitamin D insufficiency (AOR: 3.65, 95% CI: 1.23–10.85; p = 0.020; FDR q-value = 0.053), cigarette/hookah smoking (AOR: 3.65, 95% CI: 1.23, 10.85; p = 0.020; FDR q-value = 0.053) and lower age at first intercourse (AOR: 1.16, 95% CI: 1.05, 1.28; p = 0.004; FDR q-value = 0.048). The odds of BV was 0.80 and 0.78 times lower in participants who had coitus interruptus (AOR: 0.20, 95% CI: 0.06, 0.63; p = 0.006; FDR q-value = 0.048) and condom use (AOR: 0.28, 95% CI: 0.10, 0.79; p = 0.016; FDR q-value = 0.051), respectively, compared to participants who did not use contraceptives.ConclusionThese findings suggested that lower serum vitamin D levels were associated with an increased risk of developing BV. However, further studies are needed to confirm the results of the present study.

Brain damage serum biomarkers induced by COVID-19 in patients from northeast Brazil.

Neurological symptoms have been often reported in COVID-19 disease. In the present study, we evaluated brain damage associated with the increase of serum levels of neurological biomarkers S100B and neuron-specific enolase (NSE) induced by SARS-CoV-2 infection, in a population from Northeastern Brazil. Thirty-six healthy control (G1) individuals and 141 patients with confirmed COVID-19 were enrolled in this study. Positive-COVID-19 patients were divided into two groups according to the severity of illness by the National Institute of Health (NIH) criteria, 76 patients with mild symptoms for COVID-19 and (G2) and 65 with acute respiratory conditions requiring supplemental oxygenation via intensive care unit (ICU) admission (G3). A follow-up study was conducted with 23 patients from G2 14 (D14) and 21 (D21) days after the onset of symptoms. Serum levels of NSE and S100B were measured using the enzyme-linked immunoassay method (ELISA). Results revealed a significant positive association between G3 patients and S100B serum expression (p = 0.0403). The serum levels of NSE were also significantly enhanced in the G3 group compared to the control (p < 0.0001) and G2 group (p < 0.0001). In addition, clinical features such as symptoms and oxygenation status were not correlated with NSE or S100B serum expression. The follow-up study demonstrated a decrease over time (21days) in NSE serum expression (p < 0.0001). These results suggest that brain damage is followed by acute virus exposure, with no long-term effects. Future work examining COVID-19 recovery will shed light on chronic neurological damage of SARS-CoV-2 infection.

Development of an Immunoassay Method for the Sensitive Detection of Histamine and Tryptamine in Foods Based on a CuO@Au Nanoenzyme Label and Molecularly Imprinted Biomimetic Antibody.

In this paper, a novel biomimetic enzyme-linked immunoassay method (BELISA) was successfully established for the detection of histamine and tryptamine, based on catalytically active cupric oxide@gold nanoparticles (CuO@Au NPs) as a marker and a molecularly imprinted polymer (MIP) as the biomimetic antibody. Under optimized conditions, the detection limitations of the BELISA method for histamine and tryptamine were 0.04 mg L-1 and 0.14 mg L-1, respectively. For liquor spiked with histamine and tryptamine, the BELISA method delivered satisfactory recoveries ranging from 89.90% to 115.00%. Furthermore, the levels of histamine and tryptamine in fish, soy sauce, and rice vinegar samples were detected by the BELISA method and a high performance liquid chromatography method, with no significant difference between the two methods being found. Although the catalytic activity of nanozymes is still lower than that of natural enzymes, the BELISA method could still sensitively determine the histamine and tryptamine levels in food samples.

Prevalence of cardiovascular diseases in kidney transplant recipients and its relationship with asymmetric dimethylarginine, fibroblast growth factor-23 and multiple inflammatory markers.

Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of endothelial nitric oxide synthase, a marker of endothelial damage and progression of atherosclerosis. Research confirms the association of ADMA with an increased risk of cardiac complications and an increased risk of death, graft loss among kidney transplant recipients (KTRs). The aim of our study was to establish the significance of ADMA and FGF-23 as biomarkers of cardiovascular risk as well as predictors of graft failure and progression of chronic transplant kidney disease in comparison to CKD subjects. In addition, an analysis of the relationship between ADMA, FGF23 and cardiovascular diseases in CKD subjects and KTRs was performed. The study group included 132 KTRs. The control group consisted of age- and sex-adjusted 40 individuals with clinically stable CKD. ADMA, FGF-23, hs-CRP and IL-6 were measured by the enzyme-linked immunoassay method (ELISA). Parameters of body mass composition such as fat mass, FTI, lean tissue mass, LTI, body water and overhydration were assessed by multi-frequency bioimpedance analysis (BIA). Cardiovascular diseases (CVDs) were present in 31.8% of KTRs. Independent variables related to nutritional status (SGA, s-albumin), according to multivariate regression, may have an impact on the prevalence of CVD in the kidney transplant recipients' group. Our study findings suggested a correlation between ADMA and serum albumin (r=-0.41, p<0.05), oxLDL (r=-0.42, p<0.05) and overhydration (OH%, r=0.28, p<0.05). Moreover, administration of statins and/or angiotensin-converting-enzyme inhibitors was significantly related to a reduction of ADMA in KTRs. We have also identified a significant positive correlation between FGF-23 levels and inflammatory markers (hs-CRP, IL-6) and negative with overall index of renal function (eGFR-CKD EPI, eGFR-MDRD). Nutritional status, inflammation and endothelial dysfunction markers (ADMA, FGF-23) are considerably altered even in stable kidney transplant recipients.

Utilization of a Novel Immunofluorescence Instrument Prototype for the Determination of the Herbicide Glyphosate.

An enzyme-linked fluorescent immunoassay (ELFIA) method has been developed for the quantitative analytical determination of the herbicide active ingredient glyphosate in environmental matrices (surface water, soil, and plant tissues). Glyphosate, as a ubiquitous agricultural pollutant, is a xenobiotic substance with exposure in aquatic and terrestrial ecosystems due its extremely high worldwide application rate. The immunoassay developed in Project Aquafluosense is part of a fluorescence-based instrumentation setup for the in situ determination of several characteristic water quality parameters. The 96-well microplate-based competitive immunoassay method applies fluorescence signal detection in the concentration range of 0–100 ng/mL glyphosate. Application of the fluorescent signal provides a limit of detection of 0.09 ng/mL, which is 2.5-fold lower than that obtained with a visual absorbance signal. Beside the improved limit of detection, determination by fluorescence provided a wider and steeper dynamic range for glyphosate detection. No matrix effect appeared for the undiluted surface water samples, while plant tissues and soil samples required dilution rates of 1:10 and 1:100, respectively. No cross-reaction was determined with the main metabolite of glyphosate, N-aminomethylphosphonic acid, and related compounds.