A new turn-on fluorescent probe for fast detection of diabetic biomarker beta-hydroxybutyrate in vitro.

Beta-hydroxybutyrate (ß-HB) serve as a valuable diagnostic biomarker for Diabetic Ketoacidosis (DKA). Here, a new Schiff base fluorescent probe T was designed and synthesized to detect ß-HB level in aqueous solution in vitro. The probe T can detect ß-HB sensitively and selectively in DMF solution (5.0 × 10-5 M) among other interfering species (cations, anions, amino acids, biomarkers). The detection limit of probe T for ß-HB was calculated to be 0.154 µM. These results demonstrate that the probe T may provide a convenient method for rapid detection of ß-HB to diagnose diabetic ketoacidosis.

Identification of lncRNA PCAT19 as potential novel biomarker for colorectal cancer.

Long non-coding RNAs have been implicated in biological processes, and are dysregulated in types of cancer. Studies have shown that PCAT19 and CKMT2-AS1 lncRNAs promote tumor growth, invasion, and metastasis by regulating signaling pathways and modulating the gene expression. This study investigated the expression levels of lncRNAs PCAT19 and CKMT2-AS1 in colorectal tumors and normal tissues. First, Using GEPIA2 database, we compared the expression level of target lncRNAs between primary colon adenocarcinoma tumor and normal tissues. Then, the expression levels of lncRNAs PCAT19 and CKMT2-AS1 were detected in 35 colorectal tumors and paired adjacent tissues using qRT-PCR. A receiver operating characteristic (ROC) curve was used to evaluate the value of these lncRNAs as biomarkers. Statistical analysis based on GEPIA2 showed that both lncRNAs PCAT19 and CKMT2-AS1 were significantly decreased in colon adenocarcinoma compared to the normal group (P < 0.001). Experimental analysis showed that the expression level of lncRNA PCAT19 was decreased in colorectal tumors (p < 0.0001) compared to normal tissues. While the expression level of lncRNA CKMT2-AS1 did not change in tumor tissues, it decreased in non-metastatic tumors compared to normal tissues (p = 0.04). The significantly downregulation of lncRNA PCAT19 expression in both metastatic and non-metastatic colorectal tumors compared to normal tissue suggests that PCAT19 may play a role in the carcinogenesis and progression of colorectal cancer and may provide potential therapeutic targets for colorectal cancer. Based on the results of ROC curve analysis, lncRNA PCAT19 may also serves as a novel potential good biomarker in diagnosis colorectal cancer (AUC = 0.94, p < 0.0001) but no significant was found for lncRNA CKMT2-AS1 (p > 0.05).

Potential-resolved electrochemiluminescence biosensor for simultaneous determination of multiplex miRNA.

The multi-target simultaneous detection strategy based on potential-resolved electrochemiluminescence (ECL) has still been a research hotspot in analytical science, but the limited selection of ECL luminophores hinders the development of this field. Herein, polyethyleneimine functionalized perylene derivatives (PTC-PEI) and luminol functionalized gold nanoparticles (Lu-Au NPs) possessed significantly resolved emission potentials as ECL luminophore. The ternary ECL system was constructed with MoS2 nanoflowers and K2S2O8 as the coreaction accelerator and coreactant respectively, which significantly improved the cathode ECL emission of PTC-PEI. Simultaneously, the anode coreaction accelerator ZnO nanoflowers could promote the anode coreactant dissolved O2 reduction, and extremely enhanced the anode ECL emission of Lu-Au NPs. The proposed strategy addressed the major technical challenge of cross interference and competition of the coreactants for dual-biomarker detection, thus enabling accurate detection of miRNA-205 and miRNA-21 from 10 fM to 100 nM, with detection limits of 2.57 and 1.15 fM, respectively. In general, this work achieved a single-step synchronous detection of dual biomarkers, providing a new idea for the ECL detection of multiple biomarkers, and having potential value in the clinical diagnosis.

Electrochemical magneto-immunoassay for detection of ADAM10 Alzheimer's biomarker using gold nanoparticles as label.

Alzheimer's disease (AD), a neurodegenerative and progressive illness with no known cure, is the most frequent cause of dementia in older adults. Dementia in AD is usually preceded by a stage of cognitive decline known as mild cognitive impairment (MCI). MCI has gained attention as an ideal target for prevention and early interventions, considering its reversible characteristic. Here, we propose a magneto-immunoassay based on a low-cost screen-printed electrode for detecting soluble ADAM10 in plasma samples, a potential biomarker for early AD diagnosis. We present a sandwich immunoassay using magnetic beads modified with antibodies to capture ADAM10 from plasma samples and using gold nanoparticles (AuNPs) as an electrochemical label. The assay was designed to accurately detect ADAM10 in diluted plasma with a limit of detection (LoD) of 32.5 pg/mL and a dynamic linear range of 10.0-1000.0 pg/mL. Twenty-three plasma samples from the elderly, including patients with AD, MCI, and healthy subjects (negative control), were analyzed by the magneto-immunoassay and enzyme-linked immunosorbent assay (ELISA), and the ADAM10 levels correlated. This work shows the potential of this protein as a biomarker in the early diagnosis and progression of AD and provides an interesting disposable device with capabilities for applications as point-of-care (PoC) to measure ADAM10 levels.

Precise prediction of metabolites patterns using machine learning approaches in distinguishing honey and sugar diets fed to mice.

As a natural sweetener produced by honey bees, honey was recognized as being healthier for consumption than table sugar. Our previous study also indicated thatmetaboliteprofiles in mice fed honey and mixedsugardiets aredifferent. However, it is still noteworthy about the batch-to-batch consistency of the metabolic differences between two diet types. Here, the machine learning (ML) algorithms were applied to complement and calibrate HPLC-QTOF/MS-based untargeted metabolomics data. Data were generated from three batches of mice that had the same treatment, which can further mine the metabolite biomarkers. Random Forest and Extra-Trees models could better discriminate between honey and mixed sugar dietary patterns under five-fold cross-validation. Finally, SHapley Additive exPlanations tool identified phosphatidylethanolamine and phosphatidylcholine as reliable metabolic biomarkers to discriminate the honey diet from the mixed sugar diet. This study provides us new ideas for metabolomic analysis of larger data sets.

Discovery of candidate biomarkers to discriminate between Korean and Japanese red seabream (Pagrus major) using metabolomics.

Red seabream (Pagrus major) is widely consumed in East Asia. As nuclear wastewater is discharged into Japanese waterbodies, the country of origin of marine products must be accurately labeled. Here, we aimed to discover candidate metabolite biomarkers to discriminate between Korean and Japanese red seabream using LC-Orbitrap mass spectrometry. In total, 95 and 138 putative metabolites were detected via chromatographic separation of fish sampled in the warm and cold seasons, respectively. The spectrometric and chromatographic data were analyzed using principal component analysis and orthogonal partial least squares discriminant analysis. We identified 12 and 19 influential metabolites to discriminate between each origin fish in the warm and cold seasons, respectively, using variable importance in projection scores and p values. Anserine was further selected as a candidate biomarker based on receiver operating characteristic curve analysis. This study provides a basis for using anserine to determine the geographic origin of red seabream.

Capacitive biosensors for label-free and ultrasensitive detection of biomarkers.

Capacitive biosensors are label-free capacitors that can detect biomarkers with the outstanding advantages of simplicity, low cost, and ultrahigh sensitivity. A typical capacitive biosensor consists of a bioreceptor and a transducer, where the bioreceptor captures the biomarker to form a bioreceptor/biomarker conjugate and the transducer generates a detectable signal. In general, antibodies, aptamers, or proteins are exploited as the bioreceptor, while various electrodes including carbon electrodes (CEs), gold electrodes (AuEs), or interdigitated electrodes (IDEs) may serve as the transducer. Because the formation of bioreceptor/biomarker conjugates often leads to a change in capacitance, the capacitive signal is then employed for biomarker detection. This review summarizes recent advances in capacitive biosensors for the detection of biomarkers over the last five years. With a focus on the three common types of bioreceptors, i.e., antibodies, aptamers, and proteins, capacitive biosensors using CEs, AuEs, and IDEs as the transducers are discussed in detail. The immobilization of bioreceptors and signal amplification strategies are described to provide a robust overview of capacitive biosensors for biomarker detection. In addition, analytical methods and future prospects are given to support the application of capacitive biosensors.

Self-calibrated HAp:Tb-EDTA paper-based probe with dual emission ratio fluorescence for binary visual and fluorescent detection of anthrax biomarker.

Development of the portable device is significant for sensitive and rapid detection of an anthrax biomarker dipicolinic acid (DPA), existing in the B. anthracis. In this work, a novel HAp:Tb-EDTA paper-based ratiometric fluorescent sensor was obtained by a simple one-pot method for rapid and sensitive DPA detection. With the increased DPA concentration, the luminescence intensity of HAp (hydroxyapatite) remained constant, and thus applied as the stable reference signal, while the luminescence signal of Tb3+-EDTA was significantly enhanced due to the antenna effect. Therefore, the HAp:Tb-EDTA paper-based sensor was endowed with self-calibrated and ratiometric fluorescent detection performance for DPA. The proposed sensor showed excellent detection performance with a detection limit as low as 10.8 nM in the linear range of 0.5-30 µM. After combination with a smartphone, rapid visual and fluorescent detection of DPA was achieved. The proposed sensor was successfully applied to detect DPA from B. subtilis spore real samples, showing the application prospects of the paper-based sensors and opening a new horizon to develop novel paper-based point-of-care testing (POCT) devices.

Genomic characterization of Puccinia triticina using molecular marker technology / Caracterização genômica de Puccinia triticina usando tecnologia de marcadores moleculares

Leaf rust, caused by Puccinia triticina, is the most common rust disease of wheat. The fungus is an obligate parasite capable of producing infectious urediniospores. To study the genetic structure of the leaf rust population 20 RAPD primers were evaluated on 15 isolates samples collected in Pakistan. A total of 105 RAPD fragments were amplified with an average of 7 fragments per primer. The number of amplified fragments varied from 1 to 12. GL Decamer L-07 and GL Decamer L-01 amplified the highest number of bands (twelve) and primer GL Decamer A-03 amplified the lowest number of bands i.e one. Results showed that almost all investigated isolates were genetically different that confirms high genetic diversity within the leaf rust population. Rust spores can follow the migration pattern in short and long distances to neighbor areas. Results indicated that the greatest variability was revealed by 74.9% of genetic differentiation within leaf rust populations. These results suggested that each population was not completely identical and high gene flow has occurred among the leaf rust population of different areas. The highest differentiation and genetic distance among the Pakistani leaf rust populations were detected between the leaf rust population in NARC isolate (NARC-4) and AARI-11and the highest similarity was observed between NARC isolates (NARC-4) and (NARC-5). The present study showed the leaf rust population in Pakistan is highly dynamic and variable.

A ferrugem da folha, causada por Puccinia triticina, é a ferrugem mais comum do trigo. O fungo é um parasita obrigatório, capaz de produzir urediniósporos infecciosos. Para estudar a estrutura genética da população de ferrugem da folha, 20 primers RAPD foram avaliados em 15 amostras de isolados coletadas no Paquistão. Um total de 105 fragmentos RAPD foram amplificados com uma média de 7 fragmentos por primer. O número de fragmentos amplificados variou de 1 a 12. GL Decamer L-07 e GL Decamer L-01 amplificaram o maior número de bandas (doze), e o primer GL Decamer A-03 amplificou o menor número de bandas, ou seja, um. Os resultados mostraram que quase todos os isolados investigados eram geneticamente diferentes, o que confirma a alta diversidade genética na população de ferrugem da folha. Os esporos de ferrugem podem seguir o padrão de migração em distâncias curtas e longas para áreas vizinhas. Os resultados indicaram que a maior variabilidade foi revelada por 74,9% da diferenciação genética nas populações de ferrugem. Esses resultados sugeriram que cada população não era completamente idêntica e um alto fluxo gênico ocorreu entre a população de ferrugem da folha de diferentes áreas. A maior diferenciação e distância genética entre as populações de ferrugem da folha do Paquistão foram detectadas entre a população de ferrugem da folha no isolado NARC (NARC-4) e AARI-11 e a maior similaridade foi observada entre os isolados NARC (NARC-4) e (NARC-5). O presente estudo mostrou que a população de ferrugem da folha no Paquistão é altamente dinâmica e variável.

Beneficial effects of coconut oil (Cocos nucifera) on hematobiochemicl and histopathological markers in CCL4-intoxicated rabbits / Efeitos benéficos do óleo de coco (Cocos nucifera) em marcadores hematobioquímicos e histopatológicos em coelhos intoxicados com CCL4

The study was designed to investigate the effect of Coconut Oil on the levels of some liver and hematological parameters in carbon tetrachloride intoxicated rabbits. Also the antioxidant capacity of Coconut Oil for various concentrations was assessed on the basis of percent scavenging of (DPPH) free radical. Experimental animals were divided into five groups, eight rabbits in each group. These were: group A (Normal control), group B (Toxic control), group C (Standard control), group D (Treated with Coconut Oil 50 mL/kg body weight after CCl4 intoxication), group E (Treated with Coconut Oil 200 mL/kg body weight after CCl4 intoxication). The effects observed were compared with a standard hepatoprotective drug silymarine (50 mL/kg body weight). The Coconut Oil (200 mL/kg body weight) significantly (P<0.05) reduced the elevated serum levels of alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP) when compared to a toxic control rabbits. The results of extract treated rabbits were similar to silymarine administered rabbits group. Treatment with Coconut Oil root and silymarine caused no significant changes in RBC, Platelets, (Hb), (MCH) concentration and (HCT) values. However, significant (P<0.05) increase was observed in the total WBC count. The present study suggested that Coconut Oil can be used as an herbal alternative (need further exploration i.e to detect its bioactive compound and its efficacy) for hepatoprotective activit.

O estudo foi desenhado para investigar o efeito do óleo de coco nos níveis de alguns parâmetros hepáticos e hematológicos em coelhos intoxicados com tetracloreto de carbono. Também a capacidade antioxidante do óleo de coco para várias concentrações foi avaliada com base na porcentagem de eliminação de radicais livres (DPPH). Os animais experimentais foram divididos em cinco grupos, oito coelhos em cada grupo. Estes foram: grupo A (controle normal), grupo B (controle tóxico), grupo C (controle padrão), grupo D (tratado com óleo de coco 50 mL/kg de peso corporal após intoxicação por CCl4), grupo E (tratado com óleo de coco 200 mL/kg de peso corporal após intoxicação por CCl4). Os efeitos observados foram comparados com um fármaco hepatoprotetor padrão silimarina (50 mL/kg de peso corporal). O óleo de coco (200 mL/kg de peso corporal) reduziu significativamente (P<0,05) os níveis séricos elevados de alanina transaminase (ALT), aspartato transaminase (AST) e fosfatase alcalina (ALP), quando comparado a um coelho controle tóxico. Os resultados dos coelhos tratados com extrato foram semelhantes aos do grupo de coelhos administrados com silimarina. O tratamento com raiz de óleo de coco e silimarina não causou alterações significativas nos valores de RBC, Plaquetas, (Hb), (MCH) e (HCT). No entanto, observou-se aumento significativo (P<0,05) na contagem total de leucócitos. O presente estudo sugeriu que o óleo de coco pode ser usado como uma alternativa fitoterápica (precisa de mais exploração, ou seja, para detectar seu composto bioativo e sua eficácia) para atividade hepatoprotetora.

Associations between recall of proper names in story recall and CSF amyloid and tau in adults without cognitive impairment.

Neuropsychological measures sensitive to decline in the preclinical phase of Alzheimer's disease are needed. We previously demonstrated that higher amyloid-beta (Aß) assessed by positron emission tomography in adults without cognitive impairment was associated with recall of fewer proper names in Logical Memory story recall. The current study investigated the association between proper names and cerebrospinal fluid biomarkers (Aß42/40, phosphorylated tau181 [pTau181], neurofilament light) in 223 participants from the Wisconsin Registry for Alzheimer's Prevention. We assessed associations between biomarkers and delayed Logical Memory total score and proper names using binary logistic regressions. Sensitivity analyses used multinomial logistic regression and stratified biomarker groups. Lower Logical Memory total score and proper names scores from the most recent visit were associated with biomarker positivity. Relatedly, there was a 27% decreased risk of being classified Aß42/40+/pTau181+ for each additional proper name recalled. A linear mixed effects model found that longitudinal change in proper names recall was predicted by biomarker status. These results demonstrate a novel relationship between proper names and Alzheimer's disease-cerebrospinal fluid pathology.

Ag+-stabilized DNA triplex coupled with catalytic hairpin assembly and CRISPR/Cas12a amplifications for sensitive metallothionein assay.

Metallothionein (MT) is a protein biomarker secreted by liver in response to the treatment for heavy metal toxicity and oncological diseases. On the basis of a new Ag+-stabilized DNA triplex probe (Ag+-SDTP), we establish a fluorescent biosensing system for high sensitivity detection of MT by combining catalytic hairpin assembly (CHA) and the CRISPR/Cas12a signal enhancements. The MT analyte complexes with Ag+ in Ag+-SDTP to disrupt the triplex structure and to release the ssDNA strands, which trigger subsequent CHA formation of many protospacer adjacent motif (PAM)-containing dsDNAs from two hairpins. Cas12a/crRNA further recognizes these PAM sequences to activate its trans-catalytic activity to cyclically cleave the fluorescently quenched ssDNA reporters to recovery drastically amplified fluorescence for detecting MT down to 0.34 nM within the dynamic range of 1∼800 nM. Moreover, the sensing method is able to selectively discriminate MT from other non-specific molecules and can realize low level detection of MT in diluted human serums, manifesting its potentiality for monitoring the disease-specific MT biomarker at trace levels.

DAT1 and BDNF polymorphisms interact to predict Aß and tau pathology.

Previous work has associated polymorphisms in the dopamine transporter gene (rs6347 in DAT1/SLC6A3) and brain derived neurotrophic factor gene (Val66Met in BDNF) with atrophy and memory decline. However, it is unclear whether these polymorphisms relate to atrophy and cognition through associations with Alzheimer's disease pathology. We tested for effects of DAT1 and BDNF polymorphisms on cross-sectional and longitudinal ß-amyloid (Aß) and tau pathology (measured with positron emission tomography (PET)), hippocampal volume, and cognition. We analyzed a sample of cognitively normal older adults (cross-sectional n = 321) from the Alzheimer's Disease Neuroimaging Initiative (ADNI). DAT1 and BDNF interacted to predict Aß-PET, tau-PET, and hippocampal atrophy. Carriers of both "non-boptimal" DAT1 C and BDNF Met alleles demonstrated greater pathology and atrophy. Our findings provide novel links between dopamine and neurotrophic factor genes and AD pathology, consistent with previous research implicating these variants in greater risk for developing AD.

Innovative SALDI mass spectrometry analysis for Alzheimer's disease synthetic peptides detection.

Alzheimer's disease (AD) is nowadays the prominent cause of senile dementia. This pathology is characterized by aggregation of neurofibrillary tangles in cells and by the accumulation of amyloid plaques in the brain. Noteworthy, a phosphorylated protein (tau protein) and a peptide presenting two overlapping sequences of 40 or 42 residues named ß-amyloid peptides 1-40 (Aß 1-40) and 1-42 (Aß 1-42), respectively, were related to such deleterious phenomena. Singularly, the neurotoxicity was primarily attributed to the amyloid peptide Aß 1-42 form due to its capacity to fold into beta-sheets rendering it insoluble thus causing subsequent aggregation and accumulation in vivo. Regarding AD diagnosis relying on mass spectrometry, Aß 1-42 and/or Aß 1-40 were considered as relevant biomarkers being measured in cerebrospinal fluids (CSF), blood and urine. Under that context, we aimed at implementing an innovative method to evidence the depletion of circulating Aß 1-42 amyloid peptide compared to the shorter Aß 1-40 form indicating a pathologic state. We investigated Surface-Assisted Laser Desorption/Ionization Mass Spectrometry (SALDI-MS) in order to monitor the Aß 1-42/Aß 1-40 ratio without any prior sample treatment or enrichment. Taking into account that ß-amyloid peptide and 1-42 can aggregate into beta-sheets depending on the experimental conditions, specific attention was devoted to sample integrity monitoring performed by circular dichroism experiments during SALDI-MS method development.

Characterization and enrichment of spermatogonial stem cells of common carp (Cyprinus carpio).

Spermatogenesis is a systematically organized process that ensures uninterrupted sperm production in which the spermatogonial stem cells (SSCs) play a crucial role. However, the existing absence of teleost-specific molecular markers for SSCs presents a notable challenge. Herein we characterized phenotypically the spermatogonial stem cells using specific molecular markers and transmission electron microscopy. Moreover, we also describe a simple method to suppress common carp spermatogenesis using the combination of Busulfan and thermo-chemical treatment, and finally, we isolate and enrich the undifferentiated spermatogonial fraction. Our results showed that C-kit, GFRα1, and POU2 proteins were expressed by germ cells, meanwhile, undifferentiated spermatogonial populations preferentially expressed GFRα1 and POU2. Moreover, the combination of high temperature (35 °C) and Busulfan (40 mg/kg/BW) effectively suppressed the spermatogenesis of common carp males. Additionally, the amh expression analysis showed differences between the control (26 °C) when compared to 35 °C with a single or two Busulfan doses, confirming that the testes were depleted by the association of Busulfan at high temperatures. In an attempt to isolate the undifferentiated spermatogonial fraction, we used the Percoll discontinuous density gradient. Thus, we successfully dissociated the carp whole testes in different cellular fractions; subsequently, we isolated and enriched the undifferentiated spermatogonial population. Therefore, our results suggest that probably both GFRα-1 and POU2 are highly conserved factors expressed in common carp germinative epithelium and that these molecules were well conserved along the evolutionary process. Furthermore, the enriched undifferentiated spermatogonial population developed here can be used in further germ cell transplantation experiments to preserve and propagate valued and endangered fish species.

Urinary TIMP-2*IGFBP-7 to diagnose acute kidney injury in children receiving cisplatin.

BACKGROUND: Cisplatin is associated with acute kidney injury (AKI) and electrolyte abnormalities. Urine tissue inhibitor of metalloproteinase 2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP-7) may be early cisplatin-AKI biomarkers. METHODS: We conducted a 12-site prospective cohort study with pediatric patients treated with cisplatin (May 2013-December 2017). Blood and urine (measured for TIMP-2, IGFBP-7) were collected pre-cisplatin, 24-h post-cisplatin, and near hospital discharge during the first or second cisplatin cycle (early visit (EV)) and during second-to-last or last cisplatin cycle (late visit (LV)). PRIMARY OUTCOME: serum creatinine (SCr)-defined AKI (≥ stage 1). RESULTS: At EV (median (interquartile (IQR)) age: 6 (2-12) years; 78 (50%) female), 46/156 (29%) developed AKI; at LV, 22/127 (17%) experienced AKI. At EV, TIMP-2, IGFBP-7, and TIMP-2*IGFBP-7 pre-cisplatin infusion concentrations were significantly higher in participants with vs. those without AKI. At EV and LV, biomarker concentrations were significantly lower in participants with vs. those without AKI at post-infusion and near-hospital discharge. Biomarker values normalized to urine creatinine were higher in patients with AKI compared to without (LV post-infusion, median (IQR): TIMP-2*IGFBP-7: 0.28 (0.08-0.56) vs. 0.04 (0.02-0.12) (ng/mg creatinine)2/1000; P < .001). At EV, pre-infusion biomarker concentrations had the highest area under the curves (AUC) (range: 0.61-0.62) for AKI diagnosis; at LV, biomarkers measured post-infusion and near discharge yielded the highest AUCs (range: 0.64-0.70). CONCLUSIONS: TIMP-2*IGFBP-7 were poor to modest at detecting AKI post-cisplatin. Additional studies are needed to determine whether raw biomarker values or biomarker values normalized to urinary creatinine are more strongly associated with patient outcomes. A higher resolution version of the Graphical abstract is available as Supplementary information.

Predictive ability of 2-h serum neutrophil gelatinase-associated lipocalin for perinatal asphyxia-induced acute kidney injury.

BACKGROUND: Acute kidney injury (AKI) is a common cause of mortality and morbidity in asphyxiated newborns. Recent research suggests serum neutrophil gelatinase-associated lipocalin (sNGAL) as an early biomarker of AKI in newborns with perinatal asphyxia. The prospect of sNGAL is yet to be studied in Nigeria, with a huge burden of asphyxia-related neonatal deaths. METHODS: A cross-sectional analytic study was conducted on 53 asphyxiated term newborns and 53 healthy babies at the newborn unit of the Wesley Guild Hospital Ilesa, Nigeria. sNGAL was assessed in all neonates with perinatal asphyxia at baseline (within 30 min of delivery), 2 h, and 48 h of life. RESULTS: Mean sNGAL was significantly higher in asphyxiated newborns than in the control group, 81.4 (45.9) vs. 53.7 (29.2), p < 0.001. However, the mean 2-h sNGAL levels were similar in asphyxiated babies with and without AKI 100.5 (36.7) ng/ml vs. 85.3 (31.4) ng/ml, p = 0.115. The 2-h sNGAL with an AUC of 0.61 at an 83.0 ng/ml cut-off had an acceptable discriminating capability of predicting AKI. The sensitivity, specificity, positive predictive value, and negative predictive value were 80%, 51.5%, 50%, and 81%, respectively. CONCLUSION: This study shows that sNGAL levels were significantly elevated in newborns with perinatal asphyxia compared to healthy neonates, but the 2-h sNGAL is less predictive of AKI in newborns with perinatal asphyxia. The negative predictive value is high, and this may find some relevance in the attempts at early exclusion of asphyxiated babies prone to AKI. A higher resolution version of the Graphical abstract is available as Supplementary information.

Body mass index and implications for pediatric kidney health: a cross-sectional study with urinary biomarkers.

BACKGROUND: Extremes of unhealthy body weight, particularly obesity, are known to increase the risk of chronic kidney diseases. However, the current knowledge of kidney health outcomes associated with unhealthy body weight remains incomprehensive, especially in pediatrics. Therefore, the present study aimed to evaluate body mass index (BMI) and its potential associations with kidney health in a selected subset of school students in Sri Lanka. METHODS: This cross-sectional study was conducted among students of both sexes in the range of 11-18 years of age (N = 1078) in education zones with no reported cases of chronic kidney disease of uncertain etiology. Based on sex- and age-specific BMI percentiles (LMS method), the participants were classified into five BMI groups (severely thin, thin, healthy, overweight, and obese) for measurement of urinary biomarkers of kidney injury: kidney injury molecule (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), and albumin creatinine ratio (ACR). RESULTS: The median urinary levels of NGAL, ACR, and particularly KIM-1, which is a more sensitive indicator of kidney injury, showed no significant differences across the BMI strata. Importantly, moderate correlations of BMI with KIM-1 and NGAL were identified in severely thin girls. CONCLUSIONS: According to the present study, these findings do not produce plausibly strong evidence to establish a potential association of BMI with altered kidney function in the studied pediatric communities. Particularly, a likelihood of abnormal kidney health outcomes associated with undernutrition is apparent in severely thin girls. However, in-depth studies are warranted to develop a comprehensive understanding of the associations of nutritional status with pediatric kidney health in Sri Lanka. A higher resolution version of the Graphical abstract is available as Supplementary information.

(Pre)analytical considerations concerning the analysis of synovial calprotectin.

OBJECTIVES: Several studies have demonstrated that synovial calprotectin is a highly accurate biomarker in diagnosing periprosthetic joint infections (PJI). Assuring reliability is of great importance and coincides with adequate preanalytical handling. This study focuses on potentially interfering factors. METHODS: To assess the stability of synovial calprotectin, the effect of time, storage temperature, EDTA, freeze-thaw cycles, viscosity, and blood and lipid contamination was investigated. In the blood and lipid contamination experiments, hemolyzed and non-hemolyzed blood, homogenized adipose tissue, intralipid and chylomicrons were added. The effect of viscosity was investigated using freeze-thaw cycles, enzymatic pretreatment and sonification. RESULTS: No effect on synovial calprotectin levels was observed in synovial samples kept at room temperature compared to samples kept at 4 °C for up to seven days of storage. Freeze-thaw cycles did not result in significantly different calprotectin levels, although samples without EDTA resulted in higher recoveries after 1 and 2 freeze-thaw cycles. Blood and lipid contamination did not interfere with accurate synovial calprotectin analysis. Sample pretreatment to reduce sample viscosity by pretreating samples with DNAse and/or hyaluronidase did not influence calprotectin analysis. Sonification, however, resulted in increased calprotectin values. CONCLUSIONS: Synovial calprotectin is a stable biomarker and its analysis is not easily influenced by potential interfering factors.