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Background and Aim Methods Results Conclusions Although nonalcoholic fatty liver disease (NAFLD) and lipoprotein(a) [Lp(a)] are associated with cardiovascular diseases, existing data on Lp(a) in NAFLD are conflicting. The aim of this systematic review and meta‐analysis was to summarize and compare data on circulating Lp(a) between NAFLD patients and non‐NAFLD controls.A systematic literature search was performed in PubMed, Scopus, and Cochrane Library. This meta‐analysis included 18 studies containing data on 74 691 individuals (20 220 patients with NAFLD and 54 471 controls).Circulating Lp(a) was similar between patients with NAFLD and controls (standardized mean difference [SMD] 0.09; 95% confidence interval [95% CI] −0.21, 0.38). The heterogeneity among studies was high (I2 = 100%); no publication bias was detected (Egger's test P = 0.941). However, in subgroup analysis, Lp(a) was lower in NAFLD patients than controls, when Lp(a) was measured with nephelometry (SMD ‐0.26; 95% CI ‐0.46, −0.06), but not turbidimetry; this analysis also resulted in mild reduction of heterogeneity within the subgroup of nephelometry (I2 = 87%). The sensitivity analyses, based on the exclusion of studies with Newcastle‐Ottawa Scale score ≤6 (n = 5), studies in which liver biopsy was used for NAFLD diagnosis (n = 4) or studies that adopted the criteria of metabolic dysfunction‐associated fatty liver disease (n = 2), and meta‐regression analysis did not explain the high heterogeneity among studies.Overall, circulating Lp(a) was similar between NAFLD patients and non‐NAFLD controls; however, patients with NAFLD had lower circulating Lp(a) compared with controls, when Lp(a) was measured with nephelometry. These results should be cautiously interpreted, because of the high heterogeneity among studies. [ABSTRACT FROM AUTHOR]

Introduction: Vault particles are large cytoplasmic ribonucleoprotein particles that participate in inflammation. The aim of this study was to assess the diagnostic and prognostic value of major vault protein (MVP) in patients with inflammation, in order to determine whether MVP could be used as a biomarker for infection or inflammation. We also aimed to compare the diagnostic impact of MVP compared to other conventional measurements, such as CRP or white blood cell (WBC) counts. Methods: CRP and MVP levels were measured in 111 sera samples from 85 patients with inflammation admitted to a tertiary-care hospital and 26 healthy individuals during an 18-month period (2019–2020), using nephelometry and a custom MVP sandwich ELISA assay, respectively. In addition, WBC counts were measured using a commercial assay. Results: MVP levels were found to be elevated in patients with inflammation compared to healthy individuals (p < 0.0001). Moreover, MVP levels were higher in patients with inflammation due to an infectious etiology compared to those with non-infectious etiology (p = 0.0006). MVP levels significantly decreased during the first four days of infection in response to antibiotic treatment, while CRP levels showed a less-sensitive decline. An ROC curve analysis demonstrated that MVP and CRP have similarly high diagnostic accuracy, with AUCs of 0.955 and 0.995, respectively, followed by WBCs with an AUC of 0.805. Conclusions: The ROC curves demonstrated that MVP has the potential to serve as a diagnostic biomarker for inflammation and infection. Additionally, MVP levels may reflect the efficacy of antibiotic treatment. [ABSTRACT FROM AUTHOR]

Oligoclonal bands (OCB) analysis is the reference standard for detecting an intrathecal IgG synthesis. Alongside OCB, free light chains kappa (FLCκ) are considered an additional sensitive biomarker for determining patterns 2 or 3, indicating intrathecal Ig synthesis. However, kFLC IF is not suitable for detecting a monoclonal pattern 5. The primary aim of this study was to evaluate the impact of incorporating FLCκ analysis into routine cerebrospinal fluid (CSF) diagnostics instead of OCB testing on the rate of missed monoclonal IgG detection.A two-center retrospective biomarker study was conducted. OCB were identified using isoelectric focusing in polyacrylamide gels followed by silver staining or in agarose gels followed by immunofixation. FLCκ were quantified using nephelometry and FLCκ assay (Siemens).Out of a combined total of 17,755 OCB analyses conducted between 2011 and 2021, a subset of 269 cases (1.5 %) exhibited pattern 5. 98 samples (36 %), which included 18 samples with intrathecal inflammation as determined by additional OCB pattern 2 were included in the FLCκ analysis. Of those, 16 (89 %) had intrathecal FLCκ synthesis.While FLCκ offers a promising avenue for detecting an intrathecal inflammation, the pattern 5, though rare, remains a valuable additional finding of OCB analysis. A combined approach of FLCκ and OCB analysis is recommended for a comprehensive assessment of the humoral intrathecal immune response. [ABSTRACT FROM AUTHOR]

Therapeutic plasma exchange (TPE) is a cornerstone treatment for antibody‐mediated rejection (AMR) post‐organ transplantation, aiming to eliminate pathogenic donor‐specific HLA antibodies (DSA). However, limitations in HLA antibody interpretation due to the prozone‐like effect (PLE) can lead to inaccurate assessment of treatment efficacy. We present a case of a heart transplant recipient with suspected AMR, where an unexpected increase in DSA levels post‐TPE prompted investigation into PLE. Solid‐phase Luminex assays were employed to detect HLA antibodies. Serum was run neat as well as after treatment with ethylenediaminetetraacetic acid (EDTA). Nephelometry was used to detect complement levels. Laboratory analysis of pre‐TPE serum revealed higher DSA levels with EDTA treatment, characteristic of PLE. Complement measurements supported complement‐mediated interference in the pre‐TPE sample. This case underscores the importance of being aware that PLE can occur in HLA testing and can impact the interpretation of TPE efficacy for AMR. [ABSTRACT FROM AUTHOR]

Introduction: Muscle-specific kinase (MuSK)- myasthenia gravis (MG) is caused by pathogenic autoantibodies against MuSK that correlate with disease severity and are predominantly of the IgG4 subclass. The first-line treatment for MuSKMG is general immunosuppression with corticosteroids, but the effect of treatment on IgG4 and MuSK IgG4 levels has not been studied. Methods: We analyzed the clinical data and sera from 52 MuSK-MG patients (45 female, 7 male, median age 49 (range 17-79) years) from Italy, the Netherlands, Greece and Belgium, and 43 AChR-MG patients (22 female, 21 male, median age 63 (range 2-82) years) from Italy, receiving different types of immunosuppression, and sera from 46 age- and sex-matched non-disease controls (with no diagnosed diseases, 38 female, 8 male, median age 51.5 (range 20-68) years) from the Netherlands. We analyzed the disease severity (assessed by MGFA orQMG score), andmeasured concentrations of MuSK IgG4, MuSK IgG, total IgG4 and total IgG in the sera by ELISA, RIA and nephelometry. Results: We observed that MuSK-MG patients showed a robust clinical improvement and reduction of MuSK IgG after therapy, and that MuSK IgG4 concentrations, but not total IgG4 concentrations, correlated with clinical severity. MuSK IgG and MuSK IgG4 concentrations were reduced after immunosuppression in 4/5 individuals with before-after data, but data from non-linked patient samples showed no difference. Total serum IgG4 levels were within the normal range, with IgG4 levels above threshold (1.35g/L) in 1/52 MuSK-MG, 2/43 AChR-MG patients and 1/45 non-disease controls. MuSK-MG patients improved within the first four years after disease onset, but no further clinical improvement or reduction of MuSK IgG4 were observed four years later, and only 14/52 (26.92%) patients in total, of which 13 (93.3%) received general immunosuppression, reached clinical remission. Discussion: We conclude that MuSK-MG patients improve clinically with general immunosuppression but may require further treatment to reach remission. Longitudinal testing of individual patients may be clinically more useful than single measurements of MuSK IgG4. No significant differences in the serum IgG4 concentrations and IgG4/IgG ratio between AChR- and MuSK-MG patients were found during follow-up. Further studies with larger patient and control cohorts are necessary to validate the findings. [ABSTRACT FROM AUTHOR]

Free light chain (FLC) assays and the ratio of κ/λ are recommended for diagnosis, prognosis and monitoring of plasma cell dyscrasias (PCD). Limited data exists on FLC clinical specificity in patients diagnosed with other conditions. We assessed the κ, λ, and κ/λ FLC ratio using the FreeLite assay and the Sebia FLC ELISA assay in 176 patients with clinical presentations of fatigue, anemia, polyclonal hypergammaglobulinemia, joint disorders, kidney disease and non PCD-cancers with no monoclonal protein observed on serum protein electrophoresis or MASS-FIX immunoglobulin isotyping. Manufacturer defined reference intervals (RI) and glomerular filtration rate (GFR) specific RI (renal RI) were utilized. For the κ/λ ratio, 68.7 % (121/176) of specimens on the FreeLite and 87.5 % (154/176) of specimens on the Sebia assay were within RI. For κ, 68.2 % (120/176) and 72.2 % (127/176) of results were outside RI for FreeLite and Sebia respectively. For λ, 37.5 % (66/176) and 84.1 % (148/176) of FreeLite and Sebia results were outside RI. With FreeLite and Sebia, patients with kidney disease (n=25) had the highest κ/λ ratios. 44 patients (25.0 %) had GFR <60 mL/min/BSA. When renal RI were applied, 13.6 % had a FLCr outside the renal RI with FreeLite, and 4.5 % with Sebia. In a cohort of patients with signs and symptoms suggestive of PCDs, but ultimately diagnosed with other conditions, Sebia FLC had improved clinical specificity relative to FreeLite, if one was using an abnormal κ/λ ratio as a surrogate for monoclonality. [ABSTRACT FROM AUTHOR]

Computer vision (CV) technologies have been applied extensively in turbid water assessment. However, the accuracies of CV to detect turbidity is limited by several factors such as inferior image quality and adoptation of traditional machine learning (MsL). Several past studies have shown that the accuracy of CV to detect turbidity can be enhanced by employing image pre-processing and artificial intelligence (AI). Therefore, this study proposes a combined CV and convolution neural network (CNN) approach for turbid water classification in accordance with national water quality standards. A total of 71 turbid water samples in the range of 0–100 nephelometry turbidity units (NTU) were prepared from a mixture of 1000 NTU stock Formazine solution and distilled water. Digital images of water samples were acquired with the Asus Zenfone Go smartphone and nephelometry principle. Synthetic minority oversampling technique (SMOTE) was employed for image pre-processing, synthesis, and augmentation. Classification models were developed with Keras CNN architecture and TensorFlow framework. Two national water standards referred to were Malaysia National Water Quality Standard Class I (NWQS-C1) and France Système D'évaluation de la Qualité des cours d'EAU bleu aptitude (SEQ-EAU-b). The proposed CV-CNN approach was successfully implemented with 94.34–98.42% accuracy. The accuracy of CNN was slightly higher when trained with color images (98.42%) than with grayscale images (94.34%). This study demonstrated that CV and CNN are excellent tools for water quality assessment, especially for classifying water turbidity. [ABSTRACT FROM AUTHOR]

Introduction: Inflammation plays an important role in the process of carcinogenesis. It is associated with initiation, progression as well as metastasis of cancer. C-reactive protein (CRP) is a reliable marker for inflammation. Aim: The present study is designed to determine and compare the serum CRP levels in Oral Submucous Fibrosis (OSMF), Oral Leukoplakia (OL), Oral Cancer (OC) and Healthy Controls (HC) in order to assess its possible role in carcinogenesis. Materials and Methods: A total of 40 participants were equally divided in four groups i.e. OSMF, OL, OC and HC. From each participant, 5 ml of blood was obtained from antecubital vein. The serum was analysed for CRP levels using nephelometric analysis method. Results: There were total 29 males and 11 females, who were between 16 to 77 years of age, with a mean age of 44.45 ± 7.45 years. The serum CRP levels were significantly increased in OSMF, OL and OC groups as compared to HC group (p<0.05). Conclusion: Serum CRP levels can be used as diagnostic and prognostic marker for oral premalignant and malignant lesions. [ABSTRACT FROM AUTHOR]

Cell cultures are widely used in scientific research, biomedicine, and industry. When culturing, it is important to maintain certain conditions, including the concentration of cells. Monitoring of the culture growth and cell counting is an urgent task for the optimization of technological processes. Most existing methods require sampling from a culture flask. This procedure is time‐consuming and associated with the risks of contamination. We present a device able to monitor the growth of cells number in a suspension noninvasively. The device uses a laser beam that pass through the culture flask and measures the intensity of scattered light as a function of coordinate along the beam. This optical scheme allows one to obtain accurate results for both high‐ and low‐scattering samples. We constructed the wireless portable prototype for monitoring of cell culture growth directly in the incubator and demonstrated the applicability of the device for Jurkat cells and Escherichia coli bacteria. [ABSTRACT FROM AUTHOR]

Rheumatoid factors (RFs) are useful for diagnosis and classification of rheumatoid arthritis (RA). Nephelometric and turbidimetric techniques, which detect total RF but do not reveal the antibody isotype, are common diagnostic methods in clinical routine. Given the recent development of isotype-specific immunoassays, the detection of IgG, IgM, and IgA RFs represents an interesting challenge. The aim of the study was to evaluate whether specific RF tests performed as a second step after traditional nephelometry could help differentiating RA from other RF-positive diseases. We tested 117 consecutive serum samples that were RF-positive at nephelometry (BNII nephelometric analyzer, Siemens) for IgA, IgG, and IgM RF isotypes by a fluoroimmunoenzymatic assay (FEIA) on the Phadia 250 instrument (ThermoFisher). Fifty-five subjects had RA and 62 presented non-RA diagnoses. Eighteen sera (15.4%) were positive only by nephelometry, two were positive only for IgA RF, and the remaining 97 sera were all positive for IgM RF isotype (with or without IgG and IgA RF). Positive findings did not correlate with RA or non-RA diagnosis. Spearman rho correlation coefficient between nephelometric total RF and IgM isotype was moderate (0.657), and weak between total RF and IgA (0.396) and IgG (0.360) isotypes. Despite its low specificity, measurement of total RF by nephelometry still seems to be the method that performs best. As IgM, IgA, and IgG RF isotypes showed only a moderate correlation with total RF measurement, their diagnostic use as a second level test remains controversial. [ABSTRACT FROM AUTHOR]

Abstract Objective To find an adequate cut‐off point for beta trace protein (β‐TP) in nasal secretion (NS) and validate this diagnostic test with a large sample of patients. Likewise, we evaluated β‐TP test efficacy to confirm the cerebrospinal fluid (CSF) leakage closure after treatment. Methods We performed a retrospective analysis with 207 samples from 162 patients with suspected CSF leakage received in the Hospital Universitario Virgen de la Arrixaca between 2010 and 2016. Twenty‐five samples were included in the control group. Samples were obtained from NS through a swab to determine β‐TP using a nephelometry‐based assay. Sensitivity, specificity, and area under the curve (AUC) for β‐TP in NS were assessed using the receiver operator characteristic (ROC) analysis. Results Using imaging techniques, the diagnosis of CSF leak was confirmed in 57 patients (35.19%), while 105 had a negative diagnosis (64.81%). Patients with CSF leakage had significantly higher β‐TP values in NS (16.07 ± 16.94 mg/L, p

Trichophyton quinckeanum, the causative agent of mouse favus, has been responsible for several infections of animal owners in recent years and showed an infection peak around 2020 in Jena, Thuringia. The isolated T. quinckeanum strains from Thuringia differ in some positions of the ITS region compared to strains from the IHEM collection as well as to Trichophyton schoenleinii. All T. quinckeanum strains of the new genotype show up to a 100-fold increased itraconazole resistance as measured by microplate laser nephelometry (MLN) assays. Analysis of genes involved in Trichophyton indotineae azole resistance, such as Erg1, which encodes squalene epoxidase, and Erg11B, one of two copies of the sterol 14-α demethylase gene, show a 100% identity between the two T. quinckeanum genotypes. In contrast, Erg11A fragments differ in 15-nucleotide positions between both T. quinckeanum genotypes, resulting in the unique amino acid substitution Ala256Ser in resistant strains. The new T. quinckeanum genotype may have evolved through interspecies mating. Mating type analysis showed a nearly 100% identity of the minus type MAT1-1-1 fragment for all T. quinckeanum isolates. The closely related Trichophyton schoenleinii belongs to the plus mating type and has 100% identical fragments of Erg1 and Erg11B. Erg11A protein sequences of T. schoenleinii and T. quinckeanum showed increased diversity. [ABSTRACT FROM AUTHOR]

Objective: To find an adequate cut‐off point for beta trace protein (β‐TP) in nasal secretion (NS) and validate this diagnostic test with a large sample of patients. Likewise, we evaluated β‐TP test efficacy to confirm the cerebrospinal fluid (CSF) leakage closure after treatment. Methods: We performed a retrospective analysis with 207 samples from 162 patients with suspected CSF leakage received in the Hospital Universitario Virgen de la Arrixaca between 2010 and 2016. Twenty‐five samples were included in the control group. Samples were obtained from NS through a swab to determine β‐TP using a nephelometry‐based assay. Sensitivity, specificity, and area under the curve (AUC) for β‐TP in NS were assessed using the receiver operator characteristic (ROC) analysis. Results: Using imaging techniques, the diagnosis of CSF leak was confirmed in 57 patients (35.19%), while 105 had a negative diagnosis (64.81%). Patients with CSF leakage had significantly higher β‐TP values in NS (16.07 ± 16.94 mg/L, p <.001) than the control group (0.33 ± 0.12 mg/L) and patients without CSF leakage (0.61 ± 2.34 mg/L). Applying a 1 mg/L cut‐off point resulted in 96.5% sensitivity and 97.1% specificity. Positive and negative predictive values (PPV and NPV) at this cut‐off were 94.9% and 98.6%, respectively. Finally, this cut‐off point yields a test efficacy for CSF leak diagnosis of 97% (95% CI 92.9–98.9). Conclusion: Our study has established a 1 mg/L β‐TP concentration in NS as a cut‐off point for CSF leakage diagnosis with high sensibility and specificity. These results suggest that β‐TP analysis could be useful to check CSF leak resolution. Level of Evidence: 4. [ABSTRACT FROM AUTHOR]

The article provides stability and parenteral compatibility study guidelines for authors applying manuscript submissions to the journal. It describes the stability study design which covers assay validation and sample preparation. It discusses requirements in stability study including physical assays, storage and sampling, statistical considerations, stability and beyond-use-date definition, reporting results and stability of biologic drugs. An overview of compatibility study design is given.

In this study Trichoderma harzianum strain A was isolated from the rhizosphere of an argan tree in southern Morocco. Trichoderma harzianum strain A had previously demonstrated a high antagonistic potential in vitro by direct confrontation and in vivo on wheat plants in pots under greenhouse conditions against Zymoseptoria tritici, the agent of septoria leaf blotch. In this study, the activity of filtrates prepared from the liquid culture of T. harzianum A alone and from the confrontation medium with two Z. tritici strains [G1-1 (durum wheat) and A5-1 (soft wheat)] on the inhibition of Z. tritici pycnidiospore germination was studied by nephelometry. The results of the antibiosis assay revealed that filtrate 0 (A in confrontation with G1-1) and F3 (A against A5-1) showed 95% of G1-1 and A5-1 pycnidiospore inhibition at 9/10 dilution of the undiluted filtrates after 4 days of incubation. To understand and explain the antifungal activity of these filtrates, the extraction and identification of secondary molecules of peptaibiotic nature secreted by T. harzianum A in the three studied filtrates were performed. According to the results of high-performance liquid chromatography-mass spectrometry (HPLC-MS) analyses, 38 peptaibiotic molecules reported in the literature for their antifungal activity were identified in the different extracts at high concentrations (high peak intensities). These molecules are divided into nine groups, namely: Trichocryptin, Trichobrevin, Triochocryptin, Hypocompactin, Hyporodicin, Trichocompactin, Alamethicine, Trichoferin, and Trichokonin. It was also shown that the presence of the pathogen induces the production of peptaibols by the antagonistic strain of Trichoderma.

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterised by the presence of autoantibodies that are used for classification of the disease. Though routine diagnostics is commonly restricted to measuring rheumatoid factor (RF) and anti-citrullinated protein antibodies, detection of RF IgM, IgG and IgA isotypes, may increase the power of RA serodiagnosis by reducing the number of seronegative patients as well as provide prognostic information. The agglutination-based RF assays, such as nephelometry or turbidimetry, are unable to differentiate isotypes. We compared three different immunoassays used in current laboratory practice to detect RF isotypes. We tested 117 consecutive serum samples that were positive for total RF at nephelometry, from 55 RA and 62 non-RA subjects. IgA, IgG, and IgM isotypes of RF were tested by immunoenzymatic (ELISA, Technogenetics), fluoroenzymatic (FEIA, ThermoFisher) and chemiluminescence (CLIA, YHLO Biotech Co.) immunoassays. Diagnostic performance differed considerably between the assays, especially with regard to RF IgG isotype. Agreement among methods by Cohen's kappa ranged from 0.05 (RF IgG CLIA vs. FEIA) to 0.846 (RF IgM CLIA vs. FEIA). The poor agreement observed in this study indicates substantial lack of comparability among assays for RF isotypes. Harmonization of these tests requires further efforts before their measurement can be used in clinical practice. [ABSTRACT FROM AUTHOR]

Purpose: This study assessed whether measuring immunoglobulin G (IgG) from dried blood spots (DBSs) using nephelometry is a suitable remote monitoring method for patients with primary immunodeficiencies (PID). Methods: Patients receiving immunoglobulin replacement therapy for PID were included in this non-interventional single-arm study (DRKS-ID: DRKS00020522) conducted in Germany from December 4, 2019, to December 22, 2020. Three blood samples, two capillary DBSs (one mail-transferred and the other direct-transferred to the laboratory), and one intravenous were collected from each patient. IgG levels were determined using nephelometry. IgG levels were summarized descriptively, and significant differences were assessed using Wilcoxon matched-pairs signed-rank tests. Correlation and agreement between IgG levels were assessed using Spearman correlation and Bland–Altman analyses, respectively. Results: Among 135 included patients, IgG levels measured from DBS samples were lower than those measured in serum (p < 0.0001). There was no significant difference between IgG levels in direct- and mail-transferred DBS samples. There was a high degree of correlation between IgG levels in serum samples and DBS samples (r = 0.94–0.95). Although there was a bias for higher levels of IgG in serum than in DBS samples, most samples were within the 95% interval of agreement. There was a high degree of correlation between IgG levels measured in direct- and mail-transferred DBS samples (r = 0.96) with no bias based on the shipment process and most samples within the 95% interval of agreement. Conclusion: Monitoring IgG levels from DBS samples is a suitable alternative to the standard method, and results are not substantially affected by mailing DBS cards. [ABSTRACT FROM AUTHOR]

Background: Defensins are natural antimicrobial peptides that the human body secretes to protect itself from an infection. Thus, they are ideal molecules to serve as biomarkers for infection. This study was conducted to evaluate the levels of human β-defensins in patients with inflammation. Methods: CRP, hBD2 and procalcitonin were measured in 423 sera of 114 patients with inflammation and healthy individuals using nephelometry and commercial ELISA assays. Results: Levels of hBD2 in the serum of patients with an infection were markedly elevated compared to those of hBD2 in patients with inflammation of non-infectious etiology (p < 0.0001, t = 10.17) and healthy individuals. ROC analysis demonstrated that hBD2 showed the highest detection performance for infection (AUC 0.897; p < 0.001) followed by PCT (AUC 0.576; p = ns) and CRP (AUC 0.517; p = ns). In addition, analysis of hBD2 and CRP in patients' sera collected at different time points showed that hBD2 levels could help differentiate inflammation of infectious and non-infectious etiology during the first 5 days of hospitalization, while CRP levels could not. Conclusions: hBD2 has the potential to serve as a diagnostic biomarker for infection. In addition, the levels of hBD2 may reflect the efficacy of antibiotic treatment. [ABSTRACT FROM AUTHOR]

This study aimed to examine the agreement of the serum amyloid A (SAA) values determined using the ELISA test and the nephelometric automated method. This study included 80 serum samples obtained from patients with COVID-19. Samples were determined using ELISA and the nephelometric method. Wilcoxon signed ranks test showed a statistically significant difference in the calculated median values (Z = −2.432, p = 0.015). The correlation between methods was statistically significant (r = 0.603, p < 0.0001). Bland Altman analysis showed a bias of 56.6 mg/L and a relative bias of 7.4% between the methods. The results of this study indicate that further studies are needed that will examine the compliance between the ELISA and the nephelometric method for determining SAA, and the results must be carefully interpreted based on the method used. [ABSTRACT FROM AUTHOR]

• Data obtained from different FLC methods used in quality assurance were compared. • Kappa (κ) FLC measurements deviated significantly over time. • No clear association between instruments/reagents and lambda (λ) FLC measurements. • Imprecision in λFLC affects κFLC/λFLC ratio, importance for clinical assessments. Free light chain (FLC) measurements are important in diagnosing monoclonal gammopathies. As FLC are heterogeneous, different reagents and instruments for measuring FLC concentrations may give diverging results that affect assessment of patients with monoclonal gammopathies. Here we investigated agreement between different FLC methods using data from the Swedish external quality assurance (EQA) programme. The two main FLC assays, N Latex FLC (Siemens) and Serum Freelite (The Binding Site), using four nephelometric or turbidimetric instrument platforms, were compared. Results from 27 EQA rounds distributed to 11–16 Swedish hospital laboratories during 2015–2020 were investigated. The kappa (κ) FLC measurements deviated significantly over time, but when only nephelometry was used, deviation from the mean was lower (median ranges: −5% to 13 %). The CV was significantly higher for the Freelite assay (mean CV = 8.7) than for the N latex assay (mean CV = 5.7) (p < 0.0001). The coefficient of determination between all combinations of reagents and instrument platforms used was generally good (r2 = 0.76–0.87), and the correlation slope acceptable (0.81–1.2). For lambda (λ) FLC measurements, no concordance between combinations of instruments and reagents is apparent, deviating between −40 % to + 48 % from the mean. The CV was significantly higher for the combination with nephelometry and the Freelite assay (CV mean = 13.9 %) than nephelometry and the N latex assay (CV mean = 9.9 %) (p <0.001). The coefficient of determination varied between combinations of reagents and instrument platforms (r2 = 0.59–0.89) and the slope ranged between 0.48 and 1.5. Significant differences between the two reagents used were sometimes noted. Imprecision in λFLC affects the κFLC/λFLC ratio. This may be important in clinical assessment of patients, especially differentiating between monoclonal and polyclonal gammopathies. [ABSTRACT FROM AUTHOR]

In this study Trichoderma harzianum strain A was isolated from the rhizosphere of an argan tree in southern Morocco. Trichoderma harzianum strain A had previously demonstrated a high antagonistic potential in vitro by direct confrontation and in vivo on wheat plants in pots under greenhouse conditions against Zymoseptoria tritici, the agent of septoria leaf blotch. In this study, the activity of filtrates prepared from the liquid culture of T. harzianum A alone and from the confrontation medium with two Z. tritici strains [G1-1 (durum wheat) and A5-1 (soft wheat)] on the inhibition of Z. tritici pycnidiospore germination was studied by nephelometry. The results of the antibiosis assay revealed that filtrate 0 (A in confrontation with G1-1) and F3 (A against A5-1) showed 95% of G1-1 and A5-1 pycnidiospore inhibition at 9/10 dilution of the undiluted filtrates after 4 days of incubation. To understand and explain the antifungal activity of these filtrates, the extraction and identification of secondary molecules of peptaibiotic nature secreted by T. harzianum A in the three studied filtrates were performed. According to the results of high-performance liquid chromatography-mass spectrometry (HPLC-MS) analyses, 38 peptaibiotic molecules reported in the literature for their antifungal activity were identified in the different extracts at high concentrations (high peak intensities). These molecules are divided into nine groups, namely: Trichocryptin, Trichobrevin, Triochocryptin, Hypocompactin, Hyporodicin, Trichocompactin, Alamethicine, Trichoferin, and Trichokonin. It was also shown that the presence of the pathogen induces the production of peptaibols by the antagonistic strain of Trichoderma. [ABSTRACT FROM AUTHOR]

Background: Early and adequate antibiotic treatment is the cornerstone of improving clinical outcomes in patients with bloodstream infections (BSI). Delays in appropriate antimicrobial therapy have catastrophic consequences for patients with BSI. Microbiological characterization of multi-drug resistant pathogens (MDRP) allows clinicians to provide appropriate treatments. Current microbiologic techniques may take up to 96 h to identify causative pathogens and their resistant patterns. Therefore, there is an important need to develop rapid diagnostic strategies for MDRP. We tested a modified protocol to detect carbapenemase and extended-spectrum β-lactamase (ESBL) producing Gram-negative bacteria (GNB) from positive blood cultures. Methods: This is a prospective cohort study of consecutive patients with bacteremia. We developed a modified protocol using the HB&L® system to detect MDRP. The operational characteristics were analyzed for each test (HB&L-ESBL/AmpC® and HB&L-Carbapenemase® kits). The kappa coefficient, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), likelihood ratios (LR) with 95% confidence intervals (CI), and reduction in identification time of this novel method were calculated. Results: Ninety-six patients with BSI were included in the study. A total of 161 positive blood cultures were analyzed. Escherichia coli (50%, 81/161) was the most frequently identified pathogen, followed by Klebsiella pneumoniae (15%, 24/161) and Pseudomonas aeruginosa (8%, 13/161). Thirty-three percent of isolations had usual resistance patterns. However, 34/161 (21%) of identified pathogens were producers of carbapenemases and 21/161 (13%) of extended-spectrum β-lactamases. Concordance between our HB&L® modified protocol and the traditional method was 99% (159/161). Finally, identification times were significantly shorter using our HB&L®-modified protocol than traditional methods: median (IQR) 19 h (18, 22) vs. 61 h (60, 64), p < 0.001. Conclusions: Here, we provide novel evidence that using our HB&L®-modified protocol is an effective strategy to reduce the time to detect MDRP producers of carbapenemases or extended-spectrum β-lactamases, with an excellent concordance rate when compared to the gold standard. Further studies are needed to confirm these findings and to determine whether this method may improve clinical outcomes. [ABSTRACT FROM AUTHOR]

• We tested 7 types of turbidity sensors for concentrations in the range 0.05–100 g/L. • Measurements per sensor showed a tenfold variation among 12 sediment types. • Complementary scattering signals may allow for an extended SSC monitoring range, • and/or reduced sensitivity to covarying physical properties of river sediment. • Sensors are increasingly sensitive to sediment colour for concentrations > 10 g/L. To monitor the effects of rapid changes in climate and land use on sediment export from erodible environments, it is crucial to accurately quantify highly fluctuating suspended sediment concentrations (SSCs) in contrasted river systems that drain small to mesoscale catchments. To this end, we investigate the turbidity-based quantification of SSCs in the range of 0.05–100 g/L through laboratory experiments performed with 7 different types of turbidity sensors and sediments from 10 watersheds. We find that measurements of scattered light from multiple angles may allow for: (1) an extended monitoring range with SSCs up to 10–100 g/L, where enhanced uncertainty may occur near the transition in the effective operational ranges of the underlying signals (typically somewhere in the range of 1–10 g/L); and/or (2) a slightly reduced sensitivity to sediment properties. The specific turbidity of the investigated sensors is inversely related to particle diameter (D 10) for SSCs up to 1–5 g/L. Backscatter and combined-signal sensors also show a dependency on sediment colour (CIE a ∗ ), which becomes particularly prominent at SSCs above 10 g/L. We relate this increase in colour dependency with SSC to the expected effect of cumulative near-infrared light absorption associated with multiple scattering. We discuss covarying physical properties of naturally occurring river sediment that can dampen or enhance measurement sensitivity and result in turbidity-based SSC rating curves that may strongly differ in magnitude and form from curves derived for industrially prepared material that is often used for sensor calibration. Although the differences in SSC per sensor among sediment types are generally less than one order of magnitude, the systematic errors and uncertainties associated with high SSCs are typically greater than one order of magnitude and may disproportionally affect the quantification of sediment loads during large-magnitude flow events. [ABSTRACT FROM AUTHOR]

Interest in measuring immunoglobulin G Subclasses (IgG Subclasses) is increasing as more information is gathered and understanding regarding conditions associated with deficiencies of each IgG Subclass grows. Different methodologies are available for the measurement of IgG Subclasses, but their specificities vary. As a result, laboratories choose the methodology that better suits their routine, but which may not necessarily align with the needs of their population. In addition, the lack of standardization for the quantification of IgG Subclasses causes diagnostic gaps when comparing results provided by different methodologies. Thus, the purpose of our research is to compare the analytical performance of The Binding Site's (TBS) Optilite® human Immunoglobulin G (IgG) and IgG Subclasses Immunoturbidimetry assay, with the Nephelometry method routinely used in our clinical laboratory, Siemens BNII®. Our results show that the Immunoturbidimetry assay appears to be the most reliable to evaluate IgG Subclasses: the sum of IgG Subclasses and Total IgG correlate better than by Nephelometry. Although these methodologies share a similar principle, the comparison of results appears to be compromised. Therefore, prior to switching methodologies, further studies should be conducted to assess which methodology could be better applied to specific populations. It is also essential to standardise IgG Subclasses assays to reduce discrepancies that arise from comparing results. • Interest in IgG Subclasses measurement is growing. • Lack of standardization leads to diagnostic issues on comparison of results. • Immunoturbidimetry seems to be more reliable to evaluate IgG Subclasses. • These methodologies, although share a similar principle, the comparison of results appears to be compromised. • More studies must be performed to evaluate the best method for specific populations. [ABSTRACT FROM AUTHOR]

• Soluble CD89-IgA complex (sCD89-IgA) as a type of IgA immune complexes is associated with renal involvement in IgAV. • However, the ability of blood sCD89-IgA as a biomarker to predict renal involvement or multi-organ involvement in children with IgAV is not clear. • We conducted the first study of the relationship between blood sCD89-IgA levels and multiple organs involvement in pediatric IgAV patients, this is of great significance for the study of IgAV or IgAVN in children. Immunoglobulin A vasculitis (IgAV) is a kind of systemic vasculitis mediated by IgA immune complexes (IgA-ICs). Soluble CD89-IgA complex (sCD89-IgA) as a type of IgA-IC associated with renal involvement in IgAV, the ability of blood sCD89-IgA as a biomarker to predict renal or multi-organ involvement in children with IgAV is not evident, and this study mainly focused on this. The clinical characteristics and blood samples of 57 pediatric patients with IgAV were collected. ELISA was used to detect plasma IgA-ICs and sCD89-IgA levels. Serum IgA levels were detected by Nephelometry method. Statistical analysis was conducted to analyze the relationship between sex, age, serum IgA levels, plasma IgA-ICs levels, plasma sCD89-IgA levels and the involvement of multiple organs (except skin) including kidneys in these patients. Compared to patients with simple skin involvement, patients with multi-organ involvement, especially kidneys, had higher levels of plasma IgA-ICs and sCD89-IgA, and the statistical difference was significant. In addition, a high level of plasma sCD89-IgA was a high-risk factor for patients to develop multi-organ or renal involvement in addition to the skin. ROC curve analysis showed that the AUC was 0.861 (Sensitivity: 83 %, Specificity: 88 %, p < 0.0001) when plasma sCD89-IgA predicted multi-organ involvement, and AUC 0.926 (Sensitivity: 94 %, Specificity: 88 %, p < 0.0001) for predicting renal involvement. The results suggested that plasma sCD89-IgA may be a potential biomarker for predicting multi-organ involvement (in addition to skin), especially renal involvement in IgAV pediatric patients. [ABSTRACT FROM AUTHOR]

The constant increase in carbapenemase-producing Enterobacterales (CPE) constitutes a public health problem worldwide, due to the impact generated on the mortality of patients. The gastrointestinal tract is the main reservoir for this microorganism, which is why, rectal colonization becomes an important risk factor for the development of subsequent infections. One of the active epidemiological surveillance strategies is the search for colonized patients through screening cultures, to detect these multi-resistant microorganisms.We report the case of a patient, with a history of sepsis of pulmonary origin, colonized by Klebsiella pneumoniae with co-production of NDM + KPC carbapen-emases and NDM carbapenemase-producing Escherichia coli. This finding is more and more frequent, which implies a challenge in its detection and diagnosis. Patient characteristics, procedures performed and microbiological findings are described

Amaç: C-reaktif protein CRP ; inflamatuvar hastalıklarda, kardiyovasküler olaylarda, travma ve inflamasyonla ilişkili bir çok durumda belirteç olarak kullanılmaktadır. Bu çalışmada farklı cihazlar ile immunnefelometrik ve immunturbidimetrik yöntemler karşılaştırılmıştır.Gereç ve Yöntem: BN II System Siemens Diagnostics, Germany ’de rutin olarak çalışılan 150 CRP numunesi 4 düzey 10 mg/L oluşturularak çalışmaya alındı. Tüm numuneler Immage 800, Architect c16000, Beckman AU680, Cobas C501 cihazlarında çalışıldı.Bulgular: İkili grup olarak immunnefelometrik BN II System ve Immage 800 cihazlarındaki CRP sonuçları karşılaştırıldığında aralarında anlamlı fark olduğu saptanmıştır p

Background: Early and adequate antibiotic treatment is the cornerstone of improving clinical outcomes in patients with bloodstream infections (BSI). Delays in appropriate antimicrobial therapy have catastrophic consequences for patients with BSI. Microbiological characterization of multi-drug resistant pathogens (MDRP) allows clinicians to provide appropriate treatments. Current microbiologic techniques may take up to 96 h to identify causative pathogens and their resistant patterns. Therefore, there is an important need to develop rapid diagnostic strategies for MDRP. We tested a modified protocol to detect carbapenemase and extended-spectrum β-lactamase (ESBL) producing Gram-negative bacteria (GNB) from positive blood cultures. Methods: This is a prospective cohort study of consecutive patients with bacteremia. We developed a modified protocol using the HB&L® system to detect MDRP. The operational characteristics were analyzed for each test (HB&L-ESBL/AmpC® and HB&L-Carbapenemase® kits). The kappa coefficient, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), likelihood ratios (LR) with 95% confidence intervals (CI), and reduction in identification time of this novel method were calculated. Results: Ninety-six patients with BSI were included in the study. A total of 161 positive blood cultures were analyzed. Escherichia coli (50%, 81/161) was the most frequently identified pathogen, followed by Klebsiella pneumoniae (15%, 24/161) and Pseudomonas aeruginosa (8%, 13/161). Thirty-three percent of isolations had usual resistance patterns. However, 34/161 (21%) of identified pathogens were producers of carbapenemases and 21/161 (13%) of extended-spectrum β-lactamases. Concordance between our HB&L® modified protocol and the traditional method was 99% (159/161). Finally, identification times were significantly shorter using our HB&L®-modified protocol than traditional methods: median (IQR) 19 h (18, 22) vs. 61 h (60, 64), p < 0.001. Conclusions: Here, we provide novel evidence that using our HB&L®-modified protocol is an effective strategy to reduce the time to detect MDRP producers of carbapenemases or extended-spectrum β-lactamases, with an excellent concordance rate when compared to the gold standard. Further studies are needed to confirm these findings and to determine whether this method may improve clinical outcomes.

Bronchiectasis is a clinical syndrome characterized by chronic cough, sputum production, recurrent respiratory infections, and permanent bronchial dilation. The association between the level of alpha- 1 antitrypsin (AAT) and bronchiectasis is controversial. In this study, we aimed to investigate this association in children with idiopathic bronchiectasis. The study was conducted on 20 patients with idiopathic bronchiectasis as the case group (mean age 15.9±2.1) and 20 healthy individuals as the control group (mean age 14.9±2.6). Serum AAT level was measured using nephelometric analysis (g/L). Other criteria including sex, parent consanguinity, number of hospitalizations, age of the first symptom were evaluated in both groups related to AAT level. The mean serum level of AAT in the case and control groups were 1.3±0.29; 1.5±0.59, respectively, with statistical significance (P=0.001). There was a significant difference between the two groups in the AAT level distribution, according to AAT normal range (P=0.01). The case group had a more positive attitude toward consanguinity than the control group (66.7% versus 33.3%; P<0.001). The results showed that 80% of patients had the first symptom of disease under one year of age, 6.6% 1-5 years, 6.6% 5- 10 years, and 6.6% in more than ten years old. In the case group, 53.3% had a history of medical hospitalization for one time, 26.7% two times, while 20% of the patients had no medical hospitalization. Decreased AAT serum level and high consanguinity rates may be considered as two risk factors for idiopathic bronchiectasis occurrence in children. [ABSTRACT FROM AUTHOR]

Opalescence of biopharmaceutical solutions can indicate suboptimal colloidal stability and is therefore a generally undesirable attribute that requires investigation and potentially remediation. While there are numerous instrumentation options available for measuring opalescence, cross-instrument comparisons and detailed knowledge of analytical biases have been limited. Here, we highlight key findings from a multi-instrument investigation where differences in reported opalescence values are explained with particular emphasis on how the optical configuration and detector properties of each instrument affect the response of the sample and the primary formazin standards required for instrument calibration. In doing so, the particle size distribution, angular-dependent light scattering properties and refractive index of the primary formazin standard material are characterized and presented. Finally, the advanced application of a 90° angle light scattering instrument is presented as a suitable approach for making low volume, temperature controlled, nephelometric measurements of opalescence. Moreover, we demonstrate how this approach enables the simultaneous evaluation of key physical properties, such as hydrodynamic size, that are pertinent to investigations of opalescent biopharmaceuticals but have historically required the use of separate instrumentation. The findings reported here address key knowledge gaps and provide opportunities for improving the efficiency and inter-laboratory comparability of opalescence measurements for biopharmaceuticals. [ABSTRACT FROM AUTHOR]

Monoclonal antibody (mAb)-based drugs are often prone to unfavorable solution behaviors including high viscosity, opalescence, phase separation, and aggregation at the high concentrations needed to enable patient-centric subcutaneous dosage forms. Given that these can have a detrimental impact on manufacturability, stability, and delivery, approaches to identifying, monitoring, and controlling these behaviors during drug development are critical. Opalescence presents a significant challenge due to its relationship to liquid-liquid phase separation. Quantitative characterization of opalescence via turbidimetry is often restrictive due to large volume requirements (>2 mL) and alternative microscale approaches based on light transmittance (Eckhardt et al., J Pharm Sci Technol. 1994, 48: 64–70) may pose challenging with respect to accuracy. To address the need for accurate and quantitative microscale opalescence measurements, we have evaluated the use of a 'de-tuned' static light scattering detector which requires <10 μL sample per measurement. We show that tuning of the laser power to a range far below that of traditional light scattering measurements results in a stable detector response that can be accurately calibrated to the nephelometric turbidity unit (NTU) scale using appropriate standards. The calibrated detector signal yields NTU values for mAbs and other protein solutions that are comparable to a commercial turbidimeter. We used this microscale approach to characterize the opalescence of 48 commercial mAb drug products and found that the majority have opalescence below 15 NTU. However, in products with mAb concentrations greater than 75 mg/mL, a broad range of opalescence was observed, in a few cases greater than 20 NTU. These measurements as well as nephelometric characterization of several IgG1 and IgG4 mAbs across a broad pH range highlight subclass-specific tendencies toward opalescence in high concentration solutions. [ABSTRACT FROM AUTHOR]

PurposeTo develop an assay to quantify serum immunoglobulin (IgG, IgM, IgA) levels using dried blood spots (DBS) obtained on collection cards to be used as a tool for targeted screening for hypogammaglobulinemia.MethodsDBS samples, along with simultaneous serum samples, were collected from 107 healthy individuals (11 months to 57 years of age). After eluting proteins from DBS, IgG, IgM, and IgA were quantified by an enzyme-linked immunosorbent assay (ELISA). The Ig-DBS assay was validated through calibration curve performance, intra- and inter-assay precision, accuracy, specificity, selectivity, and linearity. The ELISA measurements were compared with serum Ig levels obtained using a standard nephelometry assay on serum samples collected simultaneously with the DBS samples and the results of the two assays were correlated. The stability of IgG, IgM, and IgA in the DBS was tested at room temperature, 36° to 38 °C, 2 to 8 °C, and -25 to -40 °C, from 4 to 14 days.ResultsThe Ig-DBS assay demonstrated precision, accuracy, specificity, selectivity, and linearity. Using the identified correlation coefficients of 0.834 for IgG, 0.789 for IgM, and 0.918 for IgA, the standard nephelometry-based normal reference ranges for all 3 serum Ig isotypes could be used with the Ig-DBS assay in individuals ≥16 years of age. The DBS samples were stable for 14 days at room temperature in a closed polyethylene bag.ConclusionsThe Ig-DBS assay is both sensitive and accurate for quantification of serum immunoglobulins. Samples are sufficiently stable at ambient temperature to allow for convenient shipping and analysis at a centralized laboratory. This assay therefore presents a new option for screening patients ≥16 years of age for hypogammaglobulinemia in any setting.

Bronchiectasis is a clinical syndrome characterized by chronic cough, sputum production, recurrent respiratory infections, and permanent bronchial dilation. The association between the level of alpha-1 antitrypsin (AAT) and bronchiectasis is controversial. In this study, we aimed to investigate this association in children with idiopathic bronchiectasis. The study was conducted on 20 patients with idiopathic bronchiectasis as the case group (mean age 15.9±2.1) and 20 healthy individuals as the control group (mean age 14.9±2.6). Serum AAT level was measured using nephelometric analysis (g/L). Other criteria including sex, parent consanguinity, number of hospitalizations, age of the first symptom were evaluated in both groups related to AAT level. The mean serum level of AAT in the case and control groups were 1.3±0.29; 1.5±0.59, respectively, with statistical significance (P=0.001). There was a significant difference between the two groups in the AAT level distribution, according to AAT normal range (P=0.01). The case group had a more positive attitude toward consanguinity than the control group (66.7% versus 33.3%; P

A new, integrated, instrumental, optical-electrochemical, microbiotesting system is described. This system can be used to assess the toxicity of various products and wastes, as well as the degree of environmental safety of various rooms, reservoirs, territories and sources of environmental pollution. A technique is presented as an example of the analysis carried out using the described system. This technique comprises incubation of Chlorella vulgaris tanks for 12 hours in the presence of various concentrations of 5 typical oil products in an aqueous solution containing sucrose with various mineral additives. At the same time, the elastic light scattering efficiency in the wavelength range of 820–915 nm (Iod), the optical density in the wavelength range of 435±5 nm (Avd) and the value of the redox potential (Е) were measured in each of the mentioned containers during the entire time of their incubation with an interval of 60 minutes. Then, ΔIod/Δτ, ΔAvd/Δτ, ΔE/Δτ values were calculated at each time τi, as well as partial and total degrees of activation or inhibition (+/–) of C.vulgaris vital activity by given concentration of each tested oil products. As a result, it was shown that the change in Iod characterized to a greater extent the intensity of growth and reproduction of C.vulgaris; whereas the change in E characterized to a greater extent the metabolic activity of test microorganisms. At the concentrations of the tested oil products equal to 2×10–3 vol.% and more, the higher concentrations of these products were in the medium and the more they contained aromatic components and chemically active groups, the greater degree of inhibitory effect on C.vulgaris they had. On the other hand, at the concentrations of the same oil products equal to 2×10–5 vol.% and less, the vital activity of C.vulgaris was activated even by very chemically active aromatic hydrocarbons. Moreover, the degree of such activation was so much the less, the more heterogeneous mixture of various hydrocarbons was present in the test sample. Thus, we were certain that the presented microbiotesting system provides the researcher with a sensitive, express, accessible and informative method for assessing the pro- and antimicrobial activity of various products and wastes, as well as the environmental safety of various premises and territories.

Morphological and physico-chemical properties of erythrocytes encapsulated by terpenoindol alkaloids (TIA) by nephelometry and osmotic resistance of erythrocytes in a medium with low concentrations of sodium chloride have been studied. Changes in the morphological and physico-chemical parameters of TIA-loaded erythrocyte carriers and freshly isolated erythrocytes have been studied. It was found that during the process of encapsulation of TIA by a modified hypotonic swelling method, the morphological and physicochemical parameters of erythrocytes change insignificantly in comparison with the control.

The anti-streptolysin O (ASO) test, which depends upon age and geographic location, is used to provide evidence for antecedent streptococcal infection in patients suspected of having rheumatic fever. Reference values of ASO have not previously been determined by nephelometric assay for laboratory use at Siriraj Hospital. A total of 402 serum specimens were collected from healthy adults aged between 16 and 63 years in Siriraj Hospital. They consisted of 235 blood donors, 150 subjects who were going to study aboard and 17 dentists. ASO concentrations from 5 groups according to five age ranges were compared and it was found that two age ranges which were 25 years old and younger and 26 years and older were appropriate to determine reference values. The reference values of ASO for these two age ranges, with 90% confidence intervals, were 486 (401-673) IU/ml and 385 (362-500) IU/ml, respectively.

Here, we describe a method to measure turbidity in liquids by probing a graphic pattern by optical transmission. Data are collected by a video camera, and a mathematical algorithm is used to correlate image loss with turbidity. We report high-resolution turbidity measurements of nanoparticle colloids to assess the proposed methodology. Measurements are differentially performed, which helps reduce noise from external sources. Using nephelometric turbidity units (NTU) standards, we obtain detectable measurements in a broad range of NTU from 1.95 to 1000. By implementing the proposed methodology, we proposed a video-based inexpensive yet reliable turbidimetry instrument. [ABSTRACT FROM AUTHOR]

Turbidity is used as a surrogate for suspended sediment concentration (SSC), and as a regulatory tool for indicating land use disturbance and environmental protection. Turbidity relates linearly to suspended material, however, can show non-linear responses to particulate organic matter (POM), concomitant with changes in particle size distribution (PSD). In the paper the influence of ultra-fine particulate matter (UFPM) on specific turbidity and its association with POM in suspended sediment are shown for alpine rivers in the Southern Alps of New Zealand. The approach was two-fold: a field-based investigation of the relations between SSC, POM, and turbidity sampled during event flow; and experimental work on hydrodynamic particle size effects on SSC, POM, PSD, and turbidity. Specific turbidity changes over event flow and are sensitive to increasing proportional amounts of sand, UFPM, and POM in suspension. Furthermore, the UFPM is the size fraction (<6 μm) where POM increases. The implications of the current study are that the slopes of turbidity-SSC relations are undesirable in locations that may be dominated by cyclic release of POM or distinct pulses of fine-grained material. At locations where the turbidity-SSC slopes approximate 2, the POM proportion is usually <10% of the total suspended load. However, when turbidity-SSC slopes are <1 this is likely caused by high amounts of side-scatter from UFPM concomitant with higher proportions of POM. Thus, the use of turbidity as a proxy for determining SSC may have serious consequences for the measurement of representative suspended sediment data, particularly in locations where POM may be a significant contributor to overall suspended load. [ABSTRACT FROM AUTHOR]

Introduction: Diabetes mellitus cases are continually rising all over the world. Glycated haemoglobin (HbA1c) used as a diagnostic test to measure long-term average glycaemic control in diabetic patients. Aim: To assess the precision and reproducibility of the Ion Exchange Column Chromatography Resin (IECR) method and nephelometry in comparison to High-Performance Liquid Chromatography (HPLC) with respect to the estimation of HbA1c. Materials and Methods: A cross-sectional comparative study was conducted on 50 blood samples, collected from the diabetic subjects at the Department of Biochemistry and their HbA1c values were estimated by HPLC based BioRad D-10, nephelometry and IECR techniques. HPLC was used as a gold standard method, to evaluate the sensitivity and specificity of nephelometry and IECR techniques. Data were expressed as mean±standard deviation and intraclass Correlation Coefficient and Pearson correlation were calculated. Results: The mean age of the study subjects was 53.06±7.67 years. The mean plasma HbA1c levels were 8.16±2.9, 7.62±2.5 and 7.84±2.5 and mean estimated Average Glucose (eAG) was 187.00±84.4, 172.0±76.8, and 289.46±199.9 by HPLC, Nephelometry and IECR, respectively. Compared with HPLC, nephelometry had excellent correlation (r-value 0.925); p<0.001) and IECR (r-value 0.869; p<0.001). Conclusion: Nephelometry and IECR both had better performance and showed a greater concordance with gold standard HPLC. Therefore, nephelometry and IECR can be used as an alternative assay for HbA1c estimation. [ABSTRACT FROM AUTHOR]

Apolipoprotein CIII (apoCIII) is associated with triglyceride (TG)-rich particles like VLDL and exerts an inhibitory effect of lipoprotein lipase. Increased levels are related to cardiovascular diseases and diabetes and therefore apoCIII has been proposed as a useful biomarker. Even if several commercial assays for measuring apoCIII in human plasma/serum are available, data is scarce concerning their reliability and none is used clinically. In the present study a comparative investigation has been done. Two ELISA-based methods (Cusabio Biotech and Assay Pro) and one nephelometric assay (Siemens Healthcare) were investigated. Serum and plasma samples were obtained from healthy volunteers and from samples sent to the Laboratory of Clinical Chemistry, preferably with higher levels of TGs. The Cusabio Biotech assay did not yield any valid results. However, both the methods from Assay Pro and Siemens Healthcare showed good performance with similar dynamic ranges. The latter assay had lower CV and required less work. In healthy individuals, apoCIII levels were not affected by fasting, freezing or thawing, nor did we find any gender differences. Individuals with elevated levels of TG displayed higher apoCIII values. Females with oral intake of contraceptives had higher levels. In conclusion, the nephelometric assay showed the best performance with the lowest CV, was less labor intensive than an assay based on ELISA and could therefore be suitable for clinical use. [ABSTRACT FROM AUTHOR]

Diet plays an important role in the regulation of chronic inflammation, which is linked to cardiovascular disease (CVD) and several cancers. The dietary inflammatory index (DII®) was developed to estimate the inflammatory potential of an individual's diet. We examined the association between DII scores and serum high-sensitivity C-reactive protein (hs-CRP) concentrations using the baseline data from the Japan Collaborative Cohort Study (JACC Study). Data were from 1176 control subjects (650 men and 526 women) in a nested case-control study of several cancers and CVD in the JACC Study who were free of cancer and CVD at baseline. DII scores were calculated from 26 food parameters that were derived from a validated food frequency questionnaire administered at the baseline. Energy-adjusted DII scores were calculated using the residual method. Serum hs-CRP concentrations were measured by latex-enhanced nephelometry or enzyme-immunoassay. In multivariable logistic regression analysis adjusting for potential confounders including sex, age, smoking habits, drinking habits, body mass index, and history of hypertension, the odds ratio (OR) and 95% confidence intervals (CI) for high serum hs-CRP concentrations (>1.0 mg/L) was significantly higher in the highest versus the lowest DII quartile (ORQuartile4vs1 = 1.32, 95% CI = 1.01 to 2.52). Likewise, a 1-point increase in DII score was associated with a 14% increased risk of high serum hs-CRP concentrations (ORContinuous = 1.09, 95%CI = 1.01 to 1.19). A pro-inflammatory diet, as represented by high DII scores, was associated with high serum hs-CRP concentrations in this Japanese population. [ABSTRACT FROM AUTHOR]

Objective: C-reactive protein (CRP) is used as a marker in inflammatory diseases, cardiovascular events, and many cases associated with trauma and inflammation. In this study, different devices and immunonephelometric and immunoturbidimetric method were compared. Material and Methods: Routinely studied 150 CRP samples in BN II System (Siemens, Germany) were included into the study by forming 4 level (<3.28, 3.28-5, 5-10, >10 mg/L). All samples were studied in Immage 800, Architect c16000, Beckman AU680, Cobas C501 devices. Results: When CRP results in BN II System and Immage 800 devices were compared dichotomously, it was found to be a significant difference (p<0.016). With Bonferroni-corrected Mann-Whitney U test, there is a significant difference between the CRP results in immunoturbidimetric Architect c16000, Beckman AU680, Cobas C501 immunonephelometric BN II System devices and immunonephelometric Immage 800 CRP results. There are no significant differences between other device groupings. According to the Bland-Altman analysis, the devices with the minimum mean value of the differences were immunoturbidimetric AU680 and Cobas C501 (-0.9) and immunonephelometric BN II System and immunoturbidimetric Cobas C501 (0.2). Conclusion: We think that the immunoturbidimetric measurement systems are technically superior to immunonephelometric systems, immunoturbidimetric systems provide a more convenient use in terms of labor and economics. [ABSTRACT FROM AUTHOR]

Background: Cystatin C is a key GFR biomarker. Recently, Siemens recalibrated the assay based on certified reference material ERM-DA471/IFCC. The NIH-funded longitudinal chronic kidney disease in children (CKiD) study has > 3000 cystatin C measurements based on a pre-IFCC calibrator provided by Siemens. Since cystatin C values for CKiD are now standardized to IFCC certified reference material, it is important to relate the IFCC-calibrated results to the previous values so that there are no discontinuous results. Methods: We diluted cystatin C ERM-DA471/IFCC (5.48 mg/L) into buffer and compared results with predicted ones. We then updated the cystatin C application on our BN II nephelometer to provide results based on pre-IFCC and IFCC calibrations of CKiD specimens simultaneously. We assayed 51 previously analyzed sera and 62 fresh additional specimens. Results: The predicted concentrations from the IFCC standard were consistently 17% higher than the measured values using the pre-IFCC calibration (y = 1.1686x). Similarly, the re-run and fresh sample concentrations were 17% higher via the IFCC calibration than by the pre-IFCC calibration (y = 1.168x). There was very high reliability in the measurements using the previous calibration for re-run specimens (0.99) and for 33 pristine specimens using IFCC calibration (0.99). Conclusions: We confirm the recalibration proposed by Siemens. To convert pre-IFCC results to IFCC-calibrated concentrations, the value is multiplied by 1.17. Conversely, one divides IFCC-calibrated results by 1.17 to estimate GFR via previously published pre-IFCC CKiD eGFR equations. For older adolescents, cystatin C has already been standardized and can be directly applied to the CKD-EPI equations. [ABSTRACT FROM AUTHOR]

Previous work has demonstrated that the physical properties of intracellular bacterial gas vesicles (GVs) can be analyzed in vivo using pressure nephelometry. In analyzing the buoyant state of GV-containing cyanobacteria, hydrostatic pressure within a sample cell is increased in a stepwise manner, where the concomitant collapse of GVs due to pressure and the resultant decrease in suspended cells are detected by changes in nephelometric scattering. As the relative pressure at which GVs collapse is a function of turgor pressure and cellular osmotic gradients, pressure nephelometry is a powerful tool for assaying changes in metabolism that affect turgor, such as photosynthetic and osmoregulatory processes. We have developed an updated and automated pressure nephelometer that utilizes visible-infrared (Vis-IR) spectra to accurately quantify GV critical collapse pressure, critical collapse pressure distribution, and cell turgor pressure. Here, using the updated pressure nephelometer and axenic cultures of Microcystis aeruginosa PCC7806, we demonstrate that GV critical collapse pressure is stable during mid-exponential growth phase, introduce pressure-sensitive turbidity as a robust metric for the abundance of gas-vacuolate cyanobacteria, and demonstrate that pressure-sensitive turbidity is a more accurate proxy for abundance and growth than photopigment fluorescence. As cyanobacterium-dominated harmful algal bloom (cyano- HAB) formation is dependent on the constituent cells possessing gas vesicles, characterization of environmental cyanobacteria populations via pressure nephelometry is identified as an underutilized monitoring method. Applications of this instrument focus on physiological and ecological studies of cyanobacteria, for example, cyanoHAB dynamics and the drivers associated with cyanotoxin production in aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Background: The analysis of serum free light chains (FLCs) is clinically relevant for the diagnosis and therapeutic management of clonal plasma cell disorders. This study compares the performance of monoclonal and polyclonal FLC κ and λ assays in clinical samples determined in a single academic center. Methods: Serum FLCs were analyzed from 102 patients using the Freelite (Binding Site) and N Latex (Siemens) assays on the BN ProSpec System (Siemens). When available, data for protein electrophoresis, immunofixation, C-reactive protein, and estimated glomerular filtration rate (eGFR) were combined with FLC results to evaluate performance. Results: Method evaluation showed acceptable imprecision and inaccuracy measures of <4.4% and 12.9%, respectively. Poor agreement between the methods was observed, including constant and proportional bias and poor correlation (Kendall τ, 0.671-0.901). The N Latex assay was not affected by the renal impairment estimated by eGFR, unlike the FLC κ/λ ratio results by the Freelite assay. With the Freelite assay, 98% of putative controls without monoclonal gammopathy (n = 42) showed a κ/λ ratio that was above the median of the standard diagnostic range or renal diagnostic range. A shift toward higher κ/λ ratios was also observed when retrospective data between 2011 and 2017 were compared. Conclusions: Unlike the Freelite assay, κ/λ ratios analyzed with the N Latex assay were not affected by renal failure. Both methods showed acceptable performances using nephelometry, but they were poorly correlated. A shift toward κ/λ ratios might impair the specificity of borderline increased κ/λ results. This should be considered when interpreting FLC κ and λ results. [ABSTRACT FROM AUTHOR]