Fresh Serum Research Articles

Efficacy and Safety of Autologous Serum Therapy in Chronic Spontaneous Urticaria in the Pediatric Population: A Prospective Pilot Study.

Chronic spontaneous urticaria (CSU) in children is mostly spontaneous in onset (57%). Treatment comprises long-term antihistaminic therapy without need for elaborate investigations. A subset of such patients don't respond to conventional treatment and novel therapies to help reduce pill burden is the need of the hour. To determine the efficacy and safety of autologous serum therapy (AST) in pediatric patients with chronic spontaneous urticaria. All pediatric patients, aged between 6-16 years, attended to our OPD from March 2019 to March 2020 were recruited. Clinico-demographic data and baseline investigations of all patients were performed. Two-weekly AST therapy was given for 8 visits with levocetrizine tablet 5mg on an on-demand basis. Urticaria activity score (UAS) sheet was provided to record and return every 2 weeks. Statistical analysis was done using the IBM SPSS 26 software package. Autologous serum skin test (ASST) was positive in 63% patients. Both the ASST positive and ASST negative group showed significant reduction in UAS7 score at week 14 compared to baseline. The reduction in mean UAS7 score was associated with a decreased pill burden and positive response in the patient and physician global assessment scale. No statistically significant difference between the two groups in terms of mean UAS7 reduction was found. This study has explored the efficacy and safety of autologous serum therapy in the pediatric CSU patients. Both ASST positive and ASST negative group respond to AST therapy.

Mass Spectrometry of Transferrin and Apolipoprotein CIII from Dried Blood Spots for Congenital Disorders of Glycosylation.

Dried blood spot (DBS) is the standard specimen for the newborn screening of inborn errors of metabolism (IEM) by tandem mass spectrometry. Availability of DBS for the mass spectrometric analysis of the diagnostic marker proteins, transferrin (Tf) and apolipoprotein CIII (apoCIII), of congenital disorders of glycosylation (CDG) was examined. Recovery of Tf from DBS was only slightly reduced compared with fresh serum. Although oxidation of the core polypeptides was observed, glycans of Tf and apoCIII were unaffected by storage of DBS in the ambient environment for at least 1 month. The combination of DBS and the triple quadrupole mass spectrometer used for IEM screening was sufficient to characterize the aberrant glycoprofiles of Tf and apoCIII in CDG. DBS or dried serum spot on filter paper can reduce the cost of sample transportation and potentially promote mass spectrometric screening of CDG.

Fluorescent copper conjugated curcumin cysteine nanoprobe for selective determination of Fe3+ and G-quadruplex DNA.

Thesynthesis of fluorescent copper-curcumin-cysteine (Cu-CC) as a sensing platformis reported. The synthesized probe has been confirmed by UV-visible spectroscopy, FT-IR, XRD, SEM, and TEM characterization techniques, respectively. The mechanistic aspects of selective sensing of Fe3+ and detection of different G-quadruplex DNA have been illustrated based on the "turn-off-on" concept of a regeneratable fluorescence sensing probe at λex 450nm. Interestingly, we have noticed a high selectivity to Fe3+ ion by the developed Cu-CC sensing probe in comparison withother metal ions. Furthermore, the restoration of fluorescence of the sensing probe in the presence of different DNA sequences is illustrating a cost-effective, convenient, and reliable detection methodology of DNA detection. It is highly sensitive for the determination of Pu27, promoter c-MYC quadruplex DNA in a wide linear range of 100-700nM having a detection limit of 13.1nM (RSD: 0.15%) and sensitivity of 37.2 cps/nM. Whereas, the Pu18 and H-telo telomeric DNA sequences are showing a narrow linear range, i.e., 10nM-200nM and 10nM-180nM, respectively. The real-world sample analysis performance of the regeneratable sensing probe for Pu27 DNA detection in fresh human blood serum samples is showing a satisfactory result.

Distinct common signatures of gut microbiota associated with damp-heat syndrome in patients with different chronic liver diseases.

Background: Chronic hepatitis B (CHB) and non-alcoholic fatty liver disease (NAFLD) are prevalent in China. According to traditional Chinese medicine (TCM) theory, damp-heat (DH) syndrome is common in chronic liver disease. However, the biological characteristics related to quantitative diagnosis remain to be determined. This study aimed to identify the consistent alterations in the gut microbiota associated with DH syndrome in patients with CHB or NAFLD. Methods: A total of 405 individuals were recruited, of which 146 were participants who met the consistent TCM diagnosis by three senior TCM physicians and were typical syndromes. All participants were required to provide fresh stool and serum samples. The gut microbiota was assessed by fecal 16S rRNA gene sequencing, and the serum metabolite profiles of participants were quantified by an ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) system. DH syndrome-related bacteria taxa were identified based on the 146 individuals with typical syndromes and validated in all 405 volunteers. Results: The results showed that CHB and NAFLD patients with typical TCM DH syndrome had consistently elevated serum total bile acid (TBA) levels. Significant alterations in microbial community were observed according to TCM syndromes identification. A total of 870 microbial operational taxonomic units and 21 serum metabolites showed the same variation trends in both the CHB and NAFLD DH syndrome groups. The functional analysis predicts consistent dysregulation of bile acid metabolism. Five genera (Agathobacter, Dorea, Lachnospiraceae_NC2004_group, Subdoligranulum, and unclassified_c__Clostridia) significantly decreased in abundance in patients with DH syndrome. We utilize these five genera combined with TBA to construct a random forest classifier model to predict TCM diagnosis. The diagnostic receiver-operator characteristic (ROC) areas for DH syndrome were 0.818 and 0.791 in internal tenfold cross-validation and the test set based on all 405 individuals, respectively. Conclusion: There are common signatures of gut microbiota associated with DH syndrome in patients with different chronic liver diseases. Serum TBA combined with DH-related genera provides a good diagnostic potential for DH syndrome in chronic liver disease.

Technetium‐99m radiolabeled nucleolin-targeted aptamer for glioma tumor imaging in murine models

Aptamers are small molecule DNA or RNA fragments that fold into well-defined 3D structures with high specificity and affinity towards target molecules, therefore emerging as a new class of probes for radiopharmaceutical applications. In this study, a technetium‐99m (99mTc) radiolabeled nucleolin-targeted aptamer AS1411 was developed for identifying glioma in murine models. MethodsA six-carbon amine group was linked at the 5′ end of AS1411 by DNA synthesis. Following the conjugation to NHS-MAG3, AS1411 was radiolabeled with 99mTc. Radiochemical purity and stability were evaluated by radio-TLC and gel electrophoresis. Cellular uptake and MTT assays were carried out in the nucleon-overexpressed U87 cell line to assess the biological ability of AS1411 after conjugating with FITC or radiolabeling with 99mTc. In vivo imaging of 99mTc-AS1411 was performed in glioma tumor xenografts and 99mTc and a 99mTc-labeled non-specific negative control (NC) nucleotide were used as control groups. Biodistribution studies were performed at the terminal time point of SPECT imaging. ResultsAS1411 was successfully labeled with 99mTc with the labeling yields of 81.5% ± 3.6% (n = 5) and was verified by gel electrophoresis and gel imaging. 99mTc-AS1411 was proved to be stable in fresh human serum at room temperature for 12 h. In U87 cells, 99mTc-AS1411 showed significantly higher cellular uptake than 99mTc-NC and 99mTc (9.4% ± 2.1% vs 1.9% ± 0.4% and 0.9% ± 0.1%, P < 0.01, n = 3). FITC-conjugated AS1411 demonstrated more fluorescent signals in U87 cells than NC. In addition, 99mTc-AS1411 displayed similar cellular inhibitory ability with AS1411, which was measured by MTT assay. In U87 tumor-bearing mice, 99mTc-AS1411 demonstrated high radioactive accumulation, whereas 99mTc-NC and 99mTc only showed weak tumor uptake, suggesting the specific uptake of 99mTc-AS1411 in nucleolin-positive U87 tumors in vivo. Biodistribution results further verified the imaging results. The tumor uptake of 99mTc-AS1411 was significantly higher than that of 99mTc-NC (5.81 ± 1.55%ID/g vs 0.51 ± 0.16%ID/g, n = 4, P < 0.01). Conclusion99mTc-AS1411 can be successfully prepared via the conjugation of NHS-MAG3 and be considered a promising imaging agent capable of identifying nucleolin-positive glioma tumors.

Development of rapid neutralization assay of viral hemorrhagic septicemia virus (VHSV) based on chimeric rhabdovirus expressing heterologous glycoprotein

The titer of neutralizing antibodies (NAbs) against viral hemorrhagic septicemia virus (VHSV) has been determined by conventional neutralization assay based on the observation of cytopathic effect (CPE) and plaque formation in cultured cells. However, this method requires several days for the determination and can be affected by operator bias. To develop a rapid and high-throughput neutralization assay against VHSV, we rescued a surrogate chimeric snakehead rhabdovirus, rSHRV-Gvhsv-eGFP, which has the enhanced green fluorescent protein (eGFP) gene between N and P genes and has VHSV G gene instead of SHRV G gene in the genome. The efficacy of rSHRV-Gvhsv-eGFP to determine serum neutralization activity was evaluated using various serum samples derived from New Zealand white rabbits and olive flounder (Paralichthys oliavaceus). Although neutralization titers analyzed using rSHRV-Gvhsv-eGFP were similar to the titers measured using rVHSV-A-eGFP, the time needed for the determination of neutralization titer was much shortened (24 h for rSHRV-Gvhsv-eGFP and 48 h for rVHSV-A-eGFP), proving the usefulness of rSHRV-Gvhsv-eGFP for the neutralization assay against VHSV. In addition, as the neutralization activities using rSHRV-Gvhsv-eGFP could be well-observed without adding fresh serum as a complement source, no preparation is required for the optimization of control fresh serum from naïve fish. The present results suggest that the rapid neutralization assay using rSHRV-Gvhsv-eGFP can be used to investigate neutralization activities against VHSV.

Gut microbiome and metabolic activity in type 1 diabetes: An analysis based on the presence of GADA.

ObjectiveType 1 diabetes (T1D) progression is affected by circulating glutamic acid decarboxylase antibody (GADA) that persist for many years. This study aimed at investigating whether and how the gut microbiome and its correlated metabolites change in T1D with the presence of GADA.MethodsWe used a radiobinding assay to measure GADA titers and identify the 49 T1D patients with GADA+ and 52 T1D patients with GADA-. The fresh feces and serum were analyzed using 16S rRNA gene sequencing and GC/MS. Then gut microbiome and serum metabolites were compared between the GADA+ patients and the GADA- patients. The association between gut microbial community and metabolites was assessed using the Spearman’s rank correlation.ResultsThe gut microbiome in diversity, composition, and function differed between these two groups. The abundance of genus Alistipes, Ruminococcus significantly increased in patients with GADA+ compared to that observed in the samples of GADA-. There were 54 significantly altered serum metabolites associated with tryptophan metabolism, phenylalanine, and tyrosine biosynthesis in individuals with GADA+ compared with those of GADA-For the serum metabolites, compared with those of GADA-, there were 54 significantly different metabolites with tryptophan metabolism, phenylalanine, and tyrosine and tryptophan biosynthesis decreased in individuals with GADA+. The abundance of Alistipes was positively correlated with altered metabolites involved in tryptophan metabolism.ConclusionWe demonstrate that T1D patients with GADA+ are characterised by aberrant profiles of gut microbiota and serum metabolites. The abundance of Alistipes disturbances may participate in the development of T1D patients with GADA by modulating the host’s tryptophan metabolism. These findings extend our insights into the association between the gut microbiota and tryptophan metabolism and GADA and might be targeted for preventing the development of T1D.

Analytical Validation of an Assay for Concurrent Measurement of Amino Acids in Dog Serum and Comparison of Amino Acid Concentrations between Whole Blood, Plasma, and Serum from Dogs.

Amino acids play an important role in metabolism. Comprehensive analytical validation of an assay for the concurrent measurement of a large number of amino acids in dogs is lacking, which precludes its usefulness in a clinical setting. Amino acids are often measured in plasma or whole blood. However, serum is commonly used for gastrointestinal diagnostic testing in dogs and is therefore convenient to use. This study aimed to analytically validate an assay for the concurrent measurement of amino acids in dog serum and to evaluate differences in amino acid concentrations in whole blood, plasma, and serum in dogs. Analytical validation of the assay (Biochrom 30+ Amino Acid Analyzer) was performed on fresh or banked serum samples from dogs. Whole blood, plasma, and serum from 36 healthy dogs were analyzed, and concentrations of the three sample types were compared. The assay was demonstrated to be precise, reproducible, accurate, linear, and stable for the measurement of the majority of compounds detected in dog serum. Cystine, glutamic acid, and ethanolamine were shown to be unstable at conditions commonly encountered in clinical settings. Significant differences in concentrations were identified between whole blood, plasma, and serum for 33 of 42 compounds. Amino acid profiles in serum and plasma were more similar to each other than to those in whole blood. While some amino acids are present in similar concentrations in whole blood, plasma, and serum, others are highly dependent on the type of biofluid, and measurements warrant strict adherence to sample type-based reference intervals.

Evaluation of analytical performances of a serum acetaminophen assay designed for round-the-clock use

Acetaminophen (paracetamol) voluntary (or not) intoxications are a major cause of life-threatening liver damage. Most of available assays on the market show an upper range measurement level that is close to thresholds considered as toxic levels. Therefore, high concentration samples must be further diluted in to accurately measure paracetamol levels. This study aims at assessing the performances of a Cambridge life sciences (CLS) test for acetaminophen determination in human serum, which solves this issue. Indeed, the particularities of this test consist in (i) an extended announced upper limit of quantitation, and (ii) in the use of a genetically unique enzyme (Aryl acylamidase). This evaluation encompasses comparison of results with those obtained using the acetaminophen Thermofisher test currently used in the University Hospital of Lille, and here after referred to as “reference method”. Analytical performance was evaluated on a Beckman Coulter AU480 chemistry analyzer. Within-run precision was determined by assaying 3 serum samples at 3 concentration levels (low, medium, high) in 10 replicates and between-run precision in running 5 samples on 6 days, twice a day. Linearity was assessed against a set of standards covering the entire claimed linearity range. Fifty-two fresh serum samples form patients were prospectively assessed for correlation to the reference method. The within-run and between-run precision (%CV) was respectively < 1% and < 3%. The assay showed good linearity with very low CV < 2% at concentrations up to 859 mg/L, consistent with the analytical range announced by the manufacturer. The regression equation against the reference method was Y = 1.133 x + 0.145, r2 = 0.99988. However, the lower limit of quantification (LLOQ) appears to be slightly higher than the manufacturer's stated (3 mg/L). Comparison to reference method showed that values given by the CLS assay were overestimated especially in the low range of concentration values (< 50 mg/L). The CLS acetaminophen assay has proven to have good analytical performance. Non-correlation to reference method does not affect the ability of the test to detect and to guide the management of paracetamol poisoning. The major advantage of CLS acetaminophen assay is the broad linearity range covering high acetaminophen concentrations. The use of this assay eliminates the need for dilution of highly positive samples and is particularly designed for round-the-clock use.

Precipitating Plasma.

An adult female diagnosed with granulomatosis with polyangiitis was admitted for treatment with immunosuppressive medication. When a stored lithium-heparin tube was retrieved for additional testing, the plasma was found to contain a precipitate that dissolved upon heating to 37°C. Cryoprecipitate testing on fresh serum and plasma collected in prewarmed tubes with prewarmed needles was performed. Visual precipitates and immunofixation results are shown in Fig. 1. ... ... The answers are below. Cryoprecipitation in plasma, but not serum, is consistent with cryofibrinogenemia (1, 2). The heparin plasma cryoprecipitate mainly consisted of fibrinogen and fibronectin. Part of the cryofibrinogen observed in this patient was caused by a heparin-precipitable fraction as the citrate plasma cryoprecipitate was significantly smaller (3–5). Cryofibrinogenemia may be primary or secondary to autoimmunity, infection, or malignancy (1, 2). Its association with skin-lesions and systemic thrombosis is strongest when observed in citrate plasma as this distinguishes cryofibrinogenemia from heparin-induced precipitation (1–5).

Development of a Nanocarrier-Based Splenic B Cell-Targeting System for Loading Antigens in Vitro.

B cells are types of lymphocytes that are involved in the production of antibodies against pathogens. They also deliver and present antigens for the priming of T cells. Recently, we developed an in vivo splenic marginal zone (MZ) B cell-targeting liposomes decorated with polyethylene glycol (PEG) containing a hydroxyl-terminus group (HO-PEG-Lip). In an expansion of a previous study, we used HO-PEG-Lip as an in vitro antigen delivery tool to splenic B cells to test the ability of this formulation to overcome the limitations of the poor antigen uptake ability of B cells for implantation. To achieve our purpose, various factors were optimized. These factors include cell number, liposome concentration, pre-opsonization of liposomes, fresh serum concentration, and incubation time, all of which affect the extent of interaction between liposomes and B cells. As a result, we confirmed that the HO-PEG-Lip required incubation at 37 °C for at least 20 min with 50% mouse fresh serum followed by a subsequent incubation at 37 °C for at least another 30 min with splenic B cells. By using such a loading system, fluorescein isothiocyanate (FITC)-labeled ovalbumin (OVA), a model antigen, encapsulated in HO-PEG-Lip could be efficiently loaded into splenic B cells. In addition, HO-PEG-Lip and FITC-labeled OVA encapsulated in HO-PEG-Lip were efficiently associated with MZ-B cells with high levels of complement receptors (CRs) rather than follicular B cells with low levels of CRs. These results propose a novel and useful system to efficiently load antigens into B cells in vitro by taking advantage of complement systems.

Use of a Point-of-Care Progesterone Assay to Predict Onset of Parturition in the Bitch.

An assay of circulating progesterone (P4) is commonly used to estimate progress through late gestation in the bitch. Point-of-care assays provide rapid results, a major advantage over laboratory-based assays. This study aims to compare P4 levels determined by the Catalyst® Progesterone point-of-care assay with those determined by chemiluminescent immunoassay (CLIA) and to identify the expected distribution of Catalyst P4 levels at time intervals 3 days prior to the onset of parturition in pregnant bitches. Twenty-eight pregnant bitches carrying two or more fetuses were admitted to a specialist veterinary reproduction hospital 53 days after the onset of cytological diestrus or, when that date was not known, 57 days after the last mating. Vaginal speculum examinations were performed every 6 h until the onset of cervical dilatation (TCD). Serum samples were collected twice daily (08h00 and 18h00) until TCD. For most samples, fresh serum was assayed for P4 immediately using the Catalyst assay (CatP4), then frozen until assayed by CLIA (IMMULITE 2000; ImmP4). However, for some samples, CatP4 was not analyzed prior to freezing. For these data points (n = 33), CatP4 for fresh serum was estimated from CatP4 assayed on frozen-thawed serum, based on a comparison between CatP4 on fresh vs. frozen-thawed sera. In comparison to ImmP4, CatP4 levels up to and including 7 nmol/L appear to have a constant bias of −1.69 nmol/L (limits of agreement −4.91 to 1.52), while levels >7 nmol/L appear to have a proportional bias of −17.9% (limits of agreement −68.6% to 32.7%). Bootstrapped percentiles of CatP4 results spanned 0.4–9 nmol/L within 12 h of TCD, 0.9–11 nmol/L 12–24 h from TCD, and 2.2–13.5 nmol/L 24–36 h from TCD. A CatP4 >9 nmol/L indicates a bitch that is unlikely to reach TCD within 12 h. Bitches with CatP4s below 3.5 nmol/L are likely to reach TCD within 36 h and bitches with a CatP4 below 2.2 nmol/L are likely to reach TCD within 24 h. In conclusion, the Catalyst Progesterone assay provides rapid assessment of circulating P4 in the bitch, with clinical application in the monitoring of late term pregnant bitches.

One-step synthesis of a radioiodinated anti-microRNA-21 oligonucleotide for theranostics in prostate tumor xenografts

Anti-miRNA oligonucleotide (AMO) has been used most widely to inhibit miRNA for loss-of-function studies and function as therapeutic agents. Iodine-131 (131I) radiolabeled AMO may have multiple functions for specific imaging, genetic inhibition, and radiotherapy. This study is to prepare a radioiodinated anti-miRNA-21 AMO by one-step synthesis for preliminary imaging in tumor xenografts and in vitro radiotherapy. A tyrosine was conjugated at the 3’ end of AMO via a C6 linker for labeling with 131I. After the molecular mass of AMO was confirmed by mass spectrometry, AMO was labeled with 131I by the chloramine-T method with high labeling yield (95.5% ± 3.1%). By gel electrophoresis, the radioactive distribution of 131I-AMO was located exactly where was AMO, verifying the successful radiolabeling. 131I-AMO presented high stability during 24 h of incubation in fresh human serum. The cellular uptake of 131I or FAM-labeled AMO in DU145 was significantly higher than that in PC-3 cells. After i.v. administration in mice, single-photon emission tomography (SPECT) imaging showed that increased 131I-AMO was found in DU145 tumor from 4 h to 24 h gradually. H&E staining of major organs validated the biocompatibility of 131I-AMO in vivo. Furthermore, the ability of 131I-AMO to inhibit cell growth is superior to that of 131I, along with stronger apoptosis in DU145 cells than in PC-3 cells. Therefore, AMO can be labeled with 131I via one-step synthesis after tyrosine conjugation in this study. Its high labeling yield, stability, inhibitory effect, and tumor distribution provide the potential value in the targeted theranostic role.

The Change of Cytokines and Gut Microbiome in Preterm Infants for Bronchopulmonary Dysplasia.

BackgroundBronchopulmonary dysplasia (BPD) is a devastating form of chronic lung disease that develops in preterm infants. BPD is speculated to arise from abnormal inflammatory responses, which is related to the composition of commensal microbiota, leading us to hypothesize that BPD susceptibility could be influenced by gut microbiota through inflammatory responses. This study is aimed to detect cytokines and the differences in fecal gut microbial composition in the BPD patients.MethodsBetween June 2018 and June 2020, preterm infants born at gestational age ≤30 weeks were recruited. The clinical data of infant characteristics were collected. On days 3–7 and 14–28 after birth, fresh stool samples and serum were collected. The gut microbiota composition between the BPD group and controls was detected by 16S rRNA sequencing. On days 3–7 and days 14–28, ten cytokines including IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, IFN-γ, and TNF-α were detected in the serum.ResultsThis study enrolled 38 preterm infants; the number of preterm infants in the BPD group and control group was, respectively, 18 and 20. The gestational age (27.4 ± 1.5 weeks vs. 29.5 ± 0.9 weeks, p = 0.000) and birth weight (971 ± 240 g vs. 1262 ± 335 g, p = 0.000) of the BPD group were lower than those of the control group. The present study found that the BPD group had high levels of IL-1β, IL-4, IL-6, IL-8, and TNF-α, whereas IL-10 was decreased. The Shannon diversity index of the BPD group was lower. The relative abundances of Proteobacteria in BPD group increased significantly from days 3–7 to days 14–28, while the Firmicutes was decreased. On days 14–28, the relative abundances of Proteobacteria in BPD group were significantly higher than those in the control group, while the Firmicutes was lower.ConclusionBronchopulmonary dysplasia could be influenced by gut microbiota through inflammatory responses. More studies are needed to explore the imbalance of cytokines and microbiome in BPD infants and whether it could be reversed by probiotics. This study provided a novel perspective for treating BPD.

Improved Performance in Measurement of Serum Cystatin C by Laboratories Participating in the College of American Pathologists 2019 CYS Survey.

Use of cystatin C for glomerular filtration rate estimation (eGFR) has garnered heightened interest as a means to avoid race-based medicine, since eGFRcys equations do not require specification of race. Before considering more widespread use of cystatin C, it is important to confirm that assays provide accurate measurements of cystatin C concentration, to ensure accurate GFR estimates. To determine if the accuracy of cystatin C measurements in laboratories participating in the College of American Pathologists (CAP) Cystatin C (CYS) survey has improved since 2014. Two fresh frozen serum pools, the first from healthy donors without chronic kidney disease (CKD), and the second from patients with CKD, along with a synthetically prepared elevated cystatin C pool, were sent to laboratories participating in the 2019 CYS-A survey. Target values were established by using 2 immunoassays and a bracketed 2-point calibration with diluted ERM-DA471/IFCC reference material. For the healthy donor fresh frozen pool (ERM-DA471/IFCC-traceable target of 0.725 mg/L), the all-method mean (standard deviation, coefficient of variation) was 0.731 mg/L (0.071, 9.7%). For the CKD pool (ERM-DA471/IFCC-traceable target of 2.136 mg/L), the all-method mean was 2.155 mg/L (0.182, 8.4%). For the synthetically spiked pool (ERM-DA471/IFCC-traceable target of 1.843 mg/L), the all-method mean was 1.886 mg/L (0.152, 8.1%). This represents marked improvement in accuracy and between-method agreement compared to the 2014 CAP survey. Manufacturers have markedly improved accuracy and between-method agreement of cystatin C measurement procedures since 2014, which allows for greater confidence in estimated GFR relying on cystatin C.

Clinical performance evaluation of Elecsys HIV Duo, Anti-HCV II, HBsAg II, Anti-HBc II, and Syphilis assays for routine screening of first-time blood donor samples at a French blood donation center.

Implementing fully automated analyzers has become a crucial safety step in blood donation centers. The Elecsys® assays were evaluated on the cobas e 801 module (Roche Diagnostics) for routine first-time blood donor screening. Five Elecsys infectious disease assays were tested on the cobas e 801 module at Etablissement Français du Sang, Montpellier, France (March-April 2018). The performance of Elecsys HIV Duo, Anti-HCV II, HBsAg II, Anti-HBc II, and Syphilis assays was compared with PRISM HIV O Plus, HCV, HBsAg, HBcore, and newbio pk TPHA assays (specificity analyses)/ARCHITECT Syphilis TP (sensitivity analyses), respectively. Specificity was determined in residual fresh serum samples from unselected first-time blood donors (n≥5195 per parameter). Elecsys assay sensitivity was tested using 30 preselected, positively characterized samples per assay and compared with archived routine testing data for comparator assays. Across all parameters, specificities for repeatedly reactive samples ranged from 99.81-100.00% for Elecsys assays and 99.71-99.98% for comparator assays. Sensitivities of Elecsys and comparator assays were the same for hepatitis C (85.19%), hepatitis B surface antigen (70.00%), hepatitis B core antigen antibodies (100.00%), and syphilis (100.00%). The sensitivity of the Elecsys HIV Duo assay was higher than the comparator assay (83.33% vs. 76.67%), but the difference was not statistically significant. Elecsys infectious disease assays on the cobas e 801 module demonstrated high specificity and sensitivity for screening first-time blood donor samples, and were comparable with other commercially available assays. The Elecsys assays are reliable tests for screening blood donations.

Near-infrared fluorescence imaging with indocyanine green for assessment of donor livers in a rat model of ischemia\u2013reperfusion

BackgroundAlthough marginal donor livers expand the donor pool, an ideal method for quantitatively evaluating the quality of donor livers has not been developed. This study aimed to explore the feasibility of indocyanine green (ICG) fluorescence imaging for estimating liver function in an ischemia–reperfusion model.MethodsForty-eight rats were randomly and evenly divided into 8 groups: the control group and the experimental groups (I-VII). The portal vein blocking period was 0 min, 10 min, 20 min, 30 min, 40 min, 50 min and 60 min. After blood flow was reestablished and the hemodynamics stabilized, ICG was injected through the dorsal penile vein as a bolus, and the fluorescence signal was recorded for 30 min in real time. The fluorescence intensity (FI) curve of the liver was fitted with an asymptotic regression model. Fresh liver tissues and serum were obtained from the middle lobe of the liver on postoperative day (POD) 1 and POD 7 for histopathological evaluation and liver function tests.ResultsThe growth rate of the FI curve, parameter b3, decreased from groups I to VII. According to the two sudden changes in b3 (20 min, 50 min), the experimental groups could be classified into 3 groups (A, B and C). Hepatocytes in groups I-II showed slight edema, group III began to show obvious hepatocyte edema and vacuolar degeneration, and in groups VI-VII, severe hepatocyte degeneration, necrosis and large inflammatory cell infiltration were observed. Suzuki’s scores in the 3 groups were also significantly different (P < 0.01). At the same time, the serum liver function in the experimental groups showed a significant increase on POD 1 and a decrease on POD 7. The alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total bilirubin (TB) levels of groups A, B, and C were significantly different on POD 1 (P < 0.05), and the ALT and direct bilirubin (DB) levels were significantly different on POD 7 (P < 0.05); the lactic dehydrogenase (LDH) level of the group C was significantly higher than that of the groups A and B on POD 1 and POD 7. Meanwhile, the 7-day survival rate of the rats in group C was poor compared to that of the rats in groups A and B (58.3% vs. 100% vs. 100%).ConclusionICG fluorescence imaging is effective for estimating the degree of liver damage and grading in an ischemia–reperfusion model. It probably has the potential for use in assessing the quality of the donor liver in liver transplantation.

Creatine and creatinine quantification in olympic athletes: dried blood spot analysis pilot study.

Capillary dried blood spot (DBS) samples facilitate field-based collection without venipuncture. This pilot study aims to evaluate the viability of creatine (Cr) and creatinine (Crt) quantification using fresh capillary serum (CrS/CrtS) and DBS samples (CrDBS/CrtDBS), using Flow Injection Analysis Mass Spectrometry (FIA – MS). Nine Olympic Athletes provided a capillary blood sample to assess CrS/CrtS and CrDBS/CrtDBS quantified by FIA – MS. No difference between CrtS (mean ± SD: 813.6 ± 102.4 μmol/L) and CrtDBS (812.4 ± 108.1 μmol/L) was observed with acceptable variance [SEM 88.7; CV 10.7%; ICC 0.57 (CI 95% 0.06 – 0.84)] and agreement [very strong (Spearman: r = 0.77; p < 0.01) or strong (Pearson: r = 0.56; p = 0.04); Bland Altman: lower (-193) and upper (+196) limits of agreement]. CrS (mean ± SD: 691.8 ± 165.2 μmol/L) was significantly different to CrDBS (2911 ± 571.4 μmol/L) with unacceptable variance [SEM 171.6; CV 27%; ICC 0.002 (CI 95% -0.02 – 0.07)] and ‘weak’ agreement [Spearman: r = 0.21, p = 0.47 and Pearson: r = 0.06, p = 0.84; Bland Altman lower (-3367) and upper (-1072) limits of agreement]. Crt quantification is viable using both CrtS and CrtDBS (but not for Cr and CrS/CrDBS), with the DBS tissue handling technique offering several methodological and practice facing advantages. Future work should expand upon the sample size, explore sport/discipline relevant analytes across a full competitive season, including key training, recovery and performance blocks of their periodized performance plan.

Seroprevalence in Argentinian healthcare workers after vaccination with Sputnik V

Background: Healthcare workers (HCW) were deeply affected by coronavirus disease 2019 (COVID-19). Therefore, vaccination of this population is crucial. However, data on Sputnik V vaccine are sparse. Objective: The aim of this study was to evaluate serological responses in HCWs following two doses of Sputnik V vaccine. Methods: A cross-sectional study was conducted at a tertiary-care private teaching hospital between April and May 2021. HCWs without a history of COVID-19 3 or more weeks after the second dose of Sputnik V had a fresh serum sample extracted and processed using Abbott® SARS-CoV-2 IgG II Quant. Values equal to or over 50 arbitrary units (AU)/mL were considered positive. Primary outcome was the proportion of participants who developed antibodies 21 or more days after the second dose of Sputnik V. Secondary outcomes were concentration of anti-spike IgG antibodies and comparison of such concentrations between samples taken 3–5 weeks and more than 5 weeks after the second dose. Results: The entire population developed anti-spike IgG antibodies. The median antibody concentration was 1234.8 AU/mL. When analysing days to extraction from second vaccine dose, there was no statistical difference between 21 and 35 days versus more than 35 days. Conclusion: Vaccination with Sputnik V in HCW at our institution demonstrated an efficacy of 100% in achieving quantifiable anti-spike IgG antibodies 21 or more days after the second dose.

Time and Temperature Stability of TGF-β1, EGF and IGF-1 in 20% and 100% Human Serum

Autologous serum eye drops (ASEDs) are used as a treatment for severe dry eye disease. The concentration and stability of various growth factors in ASEDs is determinative for their efficiency. We therefore assessed the concentrations of transforming growth factor beta 1 (TGF-β1), epidermal growth factor (EGF) and insulin-like growth factor 1 (IGF-1) in ASEDs following storage at 4–8, −20, −80 and −156 °C. Twenty % and 100% sera from eight healthy volunteers were analysed by the sandwich enzyme immunoassay at different time intervals up to seven months. The mean levels of TGF-β1 and EGF in undiluted and 20% serum did not differ significantly from the baseline levels in fresh serum for any storage conditions after 7 days at 4–8 °C, as well as after 4- and 7-month preservation at sub-zero temperatures. In 20% serum, no IGF-1 concentration decrease was found following 7 days of preservation at 4–8 °C. However, a decrease to 78 % and 81 % (P &lt; 0.01) of baseline values was found in 20% serum after 4-month storage at −20 °C and 7-month storage at −156 °C, respectively. A more pronounced decrease in IGF-1 was observed in undiluted serum. All assessed growth factors present in 20% frozen serum remained stable for up to 7 months. The highest stability was achieved at −80 °C. At −20 and −156 °C, some decrease in IGF-1 occurred. Our results indicate that 20% ASEDs can be stored frozen up to 7 months under proper conditions.