Perilipin 5 deletion protects against nonalcoholic fatty liver disease and hepatocellular carcinoma by modulating lipid metabolism and inflammatory responses.

The molecular mechanisms underlying the transition from nonalcoholic fatty liver disease (NAFLD) to hepatocellular carcinoma (HCC) are incompletely understood. During the development of NAFLD, Perilipin 5 (PLIN5) can regulate lipid metabolism by suppressing lipolysis and preventing lipotoxicity. Other reports suggest that the lack of PLIN5 decreases hepatic injury, indicating a protective role in NAFLD pathology. To better understand the role of PLIN5 in liver disease, we established mouse models of NAFLD and NAFLD-induced HCC, in which wild-type and Plin5 null mice were exposed to a single dose of acetone or 7,12-dimethylbenz[a]anthracene (DMBA) in acetone, followed by a 30-week high-fat diet supplemented with glucose/fructose. In the NAFLD model, RNA-seq revealed significant changes in genes related to lipid metabolism and immune response. At the intermediate level, pathways such as AMP-activated protein kinase (AMPK), signal transducer and activator of transcription 3 (STAT3), c-Jun N-terminal kinase (JNK), and protein kinase B (AKT) were blunted in Plin5-deficient mice (Plin5-/-) compared to wild-type mice (WT). In the NAFLD-HCC model, only WT mice developed liver tumors, while Plin5-/- mice were resistant to tumorigenesis. Furthermore, only 32 differentially expressed genes associated with NALFD progession were identified in Plin5 null mice. The markers of mitochondrial function and immune response, such as the peroxisome proliferator-activated receptor-γ, coactivator 1-α (PGC-1α) and phosphorylated STAT3, were decreased. Lipidomic analysis revealed differential levels of some sphingomyelins between WT and Plin5-/- mice. Interestingly, these changes were not detected in the HCC model, indicating a possible shift in the metabolism of sphingomelins during carcinogenesis.

Manipulation of THC Hair Concentrations by Commercially Available Products.

Many drug tests are carried out by means of hair analysis. The aim of the present study was to clarify if and to what extent it is possible to manipulate the results of hair analyses on tetrahydrocannabinol (THC) by using various commercially available everyday products and products advertised on the internet to be able to reduce the concentrations of drugs in hair. Fifty-four THC-positive hair samples were analyzed using liquid chromatography tandem mass spectrometry; they were analyzed untreated or treated with Vodka Gorbatschow® (n = 19), Seborin® hair tonic (n = 11), Zydot® shampoo (n = 6), Desderman® disinfectant (n = 11) and Head and Shoulders® shampoo (n = 7). A mean reduction of 52% (Zydot® shampoo) to 65% (Desderman®) was shown. Hair treatments could not be detected visually. Hair concentrations could also be decreased to non-detectability by using these everyday hair care products. Therefore, it is recommended to complement abstinence controls using hair samples by urine analysis and to not over-interpret quantitative results of THC concentrations in hair.

Quantification of Short Chain Fatty Acids (acetate, butyrate, propionate) in human blood with ion exclusion chromatography.

Short Chain Fatty Acids (SCFAs), i.e. acetate, propionate and butyrate, are mainly produced by bacterial fermentation of undigested carbohydrates in the human colon. Most important are omega-3, omega-6 and unsaturated fatty acids as being important for a healthy lifestyle. SCFAs are fundamental for proper intestinal flora and they can help to prevent type 2 diabetes. SCFAs such as acetate and propionate show promise as candidates to increase satiety-enhancing properties of food. Here we describe a simple method for determining organic acids in human blood.

The biotin interference within interference suppressed immunoassays.

BACKGROUND: Reports of false laboratory findings due to a biotin supplementation have raised concerns about the safety of immunoassays. According to current research, biotin is known to cause interference in immunoassays. Since up to 70% of medical decisions are based on laboratory results and the significantly increased intake of biotin supplements in the recent years, the reliability of immunoassays is essential. METHODS: To evaluate this reliability two experiments were conducted. In the first experiment 59 interference suppressed immunoassays of the manufacturer Roche Diagnostics were examined regarding their sensitivity to a biotin interference. In the second experiment the pharmacokinetic of biotin was examined by supplementing volunteers with biotin. RESULTS: A combination of the results of both experiments suggests that a biotin interference in laboratory findings is probable. Contrary to the current state of research on sandwich immunoassays, falsely elevated test results occur more frequently than falsely low results. CONCLUSION: The interference suppressed immunoassays have shown in the experiment that they are susceptible to a biotin interference. Therefore, laboratory institutions, medical staff and patients must be aware of the possibility of a biotin interference. As a result, Roche Diagnostics may consider reviewing the interference suppression and their indications of the tests.

Wilson disease - the impact of hyperimmunity on disease activity: A case report.

BACKGROUND: In Wilson disease lack of biliary copper excretion causes hepatocellular injury by accumulation of free toxic copper. Its overspill to serum accounts for neuronal damage as second common manifestation. Therapy with copper chelators or zinc targets the removal of this free copper. However, in some patients liver disease persists for unknown reason despite normalized free copper. The discovery of a hyperimmunity as a contributing pathogenetic factor was discovered in this case report with implication also for other liver diseases. CASE SUMMARY: A 9-year-old girl was diagnosed in August 2009 by family screening of having asymptomatic Wilson disease with elevated transaminases. Already at time of diagnosis antinuclear antibodies (ANA) were elevated without hyperimmunoglobulinemia (immunoglobulin G, IgG). After one year of therapy with D-penicillamine transaminases normalized together with free serum copper. Under continuous therapy with copper chelators free copper remained normal until today, whereas transaminases raised to alanine aminotransferase values of 571 U/L in December 2019. For hyperimmunity a tentative steroid course on top of D-penicillamine improved transaminases. Thus, hyperimmunity may have impact on liver inflammation after control of the metabolic disturbance. A retrospective cohort study confirmed the common association of elevated transaminases with ANA, but no IgG elevation. CONCLUSION: This hyperimmune-triggered condition may represent a new entity which per se or on top of other liver diseases induces liver inflammation responsive to steroids.

Retarded decline of the share of SARS-CoV-2-positive children in North Rhine-Westphalia, Germany.

Knowledge on the mechanisms of viral spread, of time-related changes, and age-specific factors of severe acute respiratory syndrome coronavirus 2 infections is important to develop recommendations aimed at controlling the pandemic. In this context, longitudinal data on proportions of positive results in different age groups are rare. Data on total positive counts and on shares of positive counts deriving from a private (MVZ) and a University (RWTH) laboratory were analyzed retrospectively and compared with public data on total positive counts of the Robert Koch Institute (RKI). Data were covered for Weeks 9-24 of the year 2020 and all patient ages. Total positive counts were lower in children compared to adults. Proportions of children and adults tested positive were 3%-5% and 5%-7%, respectively. RKI and MVZ data showed similar time-related patterns. Patients of 20-60 years of age did account for the initial virus spread (maximum infection rates at Weeks 9-11). Thereafter, infection rates decreased in older patients whereas children did not show a comparable time-related decrease. Pediatric data generated in outpatient settings and hospitals differed markedly which should be considered in further studies. In summary, compared with adults children are less affected by severe acute respiratory syndrome coronavirus 2 infections and are unlikely to account for the initial viral spread. However, children show sustained viral activity and may serve as a viral reservoir.

Deletion of Perilipin 5 Protects Against Hepatic Injury in Nonalcoholic Fatty Liver Disease via Missing Inflammasome Activation.

Nonalcoholic fatty liver disease (NAFLD) is a leading cause of chronic liver diseases with an increasing prevalence due to rising rates of obesity, metabolic syndrome and type II diabetes. Untreated NAFLD may progress to steatohepatitis (NASH) and ultimately liver cirrhosis. NAFLD is characterized by lipid accumulation, and when sufficient excess lipids are obtained, irreversible liver injury may follow. Perilipin 5 (PLIN5), a known lipid droplet coating protein and triglyceride metabolism regulator, is highly expressed in oxidatively modified tissues but it is still unclear how it affects NAFLD/NASH progress. We here studied how PLIN5 affects NAFLD development induced by a 30-week high-fat diet (HFD) administration in wild type and PLIN5 knock out (Plin5-/-) mice. The disruption of PLIN5 induced differences in lipid metabolism during HFD feeding and was associated with reduced hepatic fat accumulation. Surprisingly, Plin5-/- mice showed mitigated activation of the NLR family pyrin domain-containing 3 (NLRP3) inflammasome, leading to minor hepatic damage. We conclude that PLIN5 is a pleiotropic regulator of hepatic homeostasis in NASH development. Targeting the PLIN5 expression appears critical for protecting the liver from inflammatory activation during chronic NAFLD.

Disorders of the glucose metabolism correlate with the phenotype and the severity in women with polycystic ovary syndrome.

BACKGROUND: Different polycystic ovary syndrome (PCOS) phenotypes are correlated with different clinical severity levels. Insulin resistance correlates with higher severity. In a retrospective study, 130 patients with polycystic ovary syndrome were examined for insulin resistance. The aim of the study was to investigate relationships between glucose metabolism and different PCOS phenotypes and to identify biomarkers or combinations thereof to obtain information on the type of metabolic disorder or the severity of PCOS. METHODS: A total of 130 patients with PCOS were included in the study. Biometric data such as weight, height, cycle day and cycle length were compared with glucose metabolism parameters such as fasting glucose, insulin before and 60 and 120 minutes after 75 g glucose intake, intact proinsulin, C-peptide and ovarian function parameters including Anti-Müllerian hormone (AMH) and the soluble AMH receptor (sAMHR2). The parameters were correlated, and their diagnostic performance with respect to different expressions of PCOS was evaluated. RESULTS: The biomarkers of impaired glucose metabolism showed strong significant difference in HOMA Index, adiponectin, proinsulin and body mass index (BMI) and Insulin levels in 0-60-120 minutes of glucose tolerance test but also with parameters of ovarian function as AMH, AMH z-score sAMHR2, and sAMHR2/AMH ratio. A strong correlation between sAMHR2 and adiponectin (r = .818, P < .0001) was found indicating a relationship between the degree of glucose metabolic impairment and ovarian function. CONCLUSIONS: The parameters glucose, insulin, insulin 60 minutes after intake of 75 g glucose and adiponectin or sAMHR2 enable a biochemical classification of PCOS patients that correlates with morphological PCOS phenotypes. By determining biomarkers, it is possible to classify PCOS patients into subgroups that correlate with different PCOS phenotypes and the clinical severity.

Age-specific reference values improve the diagnostic performance of AMH in polycystic ovary syndrome.

Background The increased secretion of anti-Müllerian hormone (AMH) by the growing follicles has been supposed as a determinative feature of polycystic ovary syndrome (PCOS). The diagnostic performance of AMH in PCOS is superior compared to the free androgen index (FAI) and luteinizing hormone (LH)/follicle-stimulating hormone (FSH) quotient. We established age-dependent reference ranges to further improve the diagnostic performance of AMH. Methods In a cross-sectional study, in samples of 4712 reproductive age patients, ranging from 14 to 50 years, BMI, AMH and other reproductive hormones were determined by immunoassay or tandem mass spectrometry (LC-MS/MS) to calculate age-specific reference ranges and the diagnostic performance. Results Age-specific diagnostic performances for Elecsys® AMH, FAI and LH/FSH ratio were established in the reference group. No significant difference in BMI was found between the groups. AMH values were significantly negatively correlated with age (r = -0.628, p < 0.001) in patients with normal ovarian function, but there was no correlation between age and AMH levels in PCOS patients (r = - 0.041, p < 0.174). In all the study groups, AMH showed a weak correlation between FAI and LH/FSH ratio (r = 0.302, p < 0.001 and r = 0.434, p < 0.001, respectively). The sensitivity/specificity for AMH, FAI and LH/FSH ratio were 89/96%, 71/69% and 75/72%, respectively, according to the Youden index. Conclusions We determined the age-dependent reference ranges for serum AMH levels in a large population-based study and calculated the age-specific diagnostic performance of FAI and LH/FSH ratio, which allows physicians to evaluate patients with PCOS who have normal AMH levels. AMH is suggested as the strongest diagnostic marker in patients with PCOS compared to FAI and LH/FSH ratio.

Investigation of soluble anti-Müllerian hormone receptor type 2 as a biomarker for diagnosis of female fertility disorders.

RESEARCH QUESTION: The ectodomain of the anti-Müllerian hormone (AMH) type 2 receptor is shed by proteases under certain conditions, which makes it measurable in the blood. The aim of this study was to identify correlations of soluble anti-Müllerian hormone receptor type 2 (sAMHR2) with other sex hormone concentrations and to assess whether sAMHR2 may serve as a new biomarker in fertility disorders. DESIGN: In a retrospective cross-sectional study of women (n = 186) with different gynaecological-endocrinological disorders, mixed-effect models were used to analyse the correlation with established diagnostic hormone tests. Receiver operating characteristic curve analysis was performed to assess the diagnostic performance. RESULTS: There was a strong correlation of sAMHR2 with LH (r = 0.898) and FSH (r = 0.846) and a moderate correlation of AMH with testosterone (r = 0.666) and androstenedione (r = 0.696) (all P < 0.001). In diagnoses of polycystic ovary syndrome (PCOS), AMH showed the best performance (area under the curve [AUC] 0.981, cut-off 4 ng/ml) with 96% sensitivity and 94% specificity. sAMHR2 concentrations and sAMHR2/AMH ratios were elevated in women with ovarian insufficiency, compared with all other study groups, including post-menopausal women on hormone replacement therapy. Highest sensitivity and specificity (100% and 98.2%, respectively) were achieved with sAMHR2/AMH ratio for the diagnosis of post-menopausal status (cut-off 68.85). The sAMHR2/AMH ratio (AUC 0.997) had a better performance than sAMHR2 (AUC 0.947), FSH (AUC 0.989) and LH (AUC 0.967). CONCLUSIONS: The sAMHR2/AMH ratio may serve as a useful biomarker for infertility diagnostics to identify post-menopausal women.

Reference change values of M-protein, free light chain and immunoglobulins in monoclonal gammopathy.

OBJECTIVES: Clinical decisions in patients with monoclonal gammopathies may be highly imprecise because of variations of parameters used in diagnosis. In this study, we aimed to calculate the variation in M-protein, free light chains (FLCs), and immunoglobulins in respective patients. DESIGN & METHODS: We analyzed the data of clinically stable patients with monoclonal gammopathy (MG), which were monitored for 7-years to determine the biological variations and reference change values (RCV) of serum M-protein, monoclonal serum FLCs and immunoglobulin (Ig) concentrations. Patients that were included in the study had no change in diagnosis and showed <5 g/L change in serum M-protein during the monitoring. From the patients included at least 3 consecutive samples were analyzed within 8 months and 7 years of initial diagnosis. RESULTS: The total coefficient of variations (CV) was calculated for M-protein and involved/uninvolved fractions of FLCs and immunoglobulins. From 38 patients and 456 samples that were included in the study, the total CVs were calculated for serial M-proteins (8.9%), serum involved FLCs (iFLC, 21.4%), involved Ig (i-Ig, 8.7%) and uninvolved Ig (u-Ig, 9.1%). Combining these CVs and the interassay analytical CVs, we calculated the biological CV for the serum M-protein (8.4%), serum iFLC concentration (21.1%), i-Ig (8.6%) and u-Ig (9.0%). A significant correlation was found in multiple myeloma patients between the κ/λ light chain ratio (rFLC) with i-Ig, the difference between i-Ig level and u-Ig level (d-Ig) and ratio Ig (r-Ig) (r = 0.790, 0.703 and 0.711, respectively). These correlations were not found in patients suffering from MG of undetermined significance and smoldering multiple myeloma. CONCLUSIONS: i-Ig determinations may be an alternative to M-protein for MGs. The variations in serum FLC measurements during MG monitoring were greater than those observed in serum M-proteins and therefore need to be more rigorously revised for recommendations.

Liver Fibrosis and Metabolic Alterations in Adults With alpha-1-antitrypsin Deficiency Caused by the Pi*ZZ Mutation.

BACKGROUND & AIMS: Alpha-1 antitrypsin deficiency (AATD) is among the most common genetic disorders. Severe AATD is caused by a homozygous mutation in the SERPINA1 gene that encodes the Glu342Lys substitution (called the Pi*Z mutation, Pi*ZZ genotype). Pi*ZZ carriers may develop lung and liver diseases. Mutation-associated lung disorders have been well studied, but less is known about the effects in liver. We assessed the liver disease burden and associated features in adults with this form of AATD. METHODS: We collected data from 554 Pi*ZZ adults (403 in an exploratory cohort, 151 in a confirmatory cohort), in 9 European countries, with AATD who were homozygous for the Pi*Z mutation, and 234 adults without the Pi*Z mutation (controls), all without pre-existing liver disease. We collected data on demographic parameters, comorbidities, lung- and liver-related health, and blood samples for laboratory analysis. Liver fibrosis was assessed non-invasively via the serum tests Aspartate Aminotransferase to Platelet Ratio Index and HepaScore and via transient elastography. Liver steatosis was determined via transient elastography-based controlled attenuation parameter. We performed histologic analyses of livers from transgenic mice that overexpress the AATD-associated Pi*Z variant. RESULTS: Serum levels of liver enzymes were significantly higher in Pi*ZZ carriers vs controls. Based on non-invasive tests for liver fibrosis, significant fibrosis was suspected in 20%-36% of Pi*ZZ carriers, whereas signs of advanced fibrosis were 9- to 20-fold more common in Pi*ZZ carriers compared to non-carriers. Male sex; age older than 50 years; increased levels of alanine aminotransferase, aspartate aminotransferase, or γ-glutamyl transferase; and low numbers of platelets were associated with higher liver fibrosis burden. We did not find evidence for a relationship between lung function and liver fibrosis. Controlled attenuation parameter ≥280 dB/m, suggesting severe steatosis, was detected in 39% of Pi*ZZ carriers vs 31% of controls. Carriers of Pi*ZZ had lower serum concentrations of triglyceride and low- and very-low-density lipoprotein cholesterol than controls, suggesting impaired hepatic secretion of lipid. Livers from Pi*Z-overexpressing mice had steatosis and down-regulation of genes involved in lipid secretion. CONCLUSIONS: In studies of AATD adults with the Pi*ZZ mutation, and of Pi*Z-overexpressing mice, we found evidence of liver steatosis and impaired lipid secretion. We identified factors associated with significant liver fibrosis in patients, which could facilitate hepatologic assessment and counseling of individuals who carry the Pi*ZZ mutation. ClinicalTrials.gov Number NCT02929940.

Has GnRH a direct role in AMH regulation?

OBJECTIVE: Anti-Mullerian hormone (AMH) together with luteinizing hormone (LH) and follicle-stimulating hormone (FSH) plays crucial roles in gonadal functions. However, the possible effects of GnRH on AMH via the hypothalamic-pituitary-gonadal (HPG) axis remain unexplored. We aimed to explore the changes in AMH levels after bolus GnRH stimulation and understand the relationship of AMH with FSH and LH in healthy subjects. METHODS: Thirty-one prepubertal children (15 males/16 females) and 78 adults (36 males/42 females) were included. We collected basal (0 minute) samples for determining levels of hormones. After GnRH treatment at a dose of 2.5 µg/kg body weight (maximum of 100 µg/kg body weight) intravenously, blood was collected at 30 minutes intervals for 120 minutes. Serum LH, FSH and AMH were measured by electrochemiluminometric assays. RESULTS: After injection of GnRH, AMH levels were significantly decreased in 30 minutes (P < 0.001) in all groups with parallel increase of FSH and LH. In the second 30 minutes, all hormones levels reversed. There was also a moderate correlation between AMH and FSH (r = -0.430, P < 0.001). CONCLUSIONS: GnRH lowers serum AMH levels, which have a negative correlation with the increase in gonadotrophins. These data pinpoint GnRH as an important factor of the AMH regulation, leading new opportunities for the understanding of AMH role in reproductive function and dysfunction.

Mining the Age-Dependent Reference Intervals of B Vitamins from Routine Laboratory Test Results.

OBJECTIVE: To describe the reference intervals of folate, vitamin B12, vitamin B6, and vitamin B1 by sex and age. METHODS: The study was performed by gathering data on 55,811 subjects from 57 medical centers. Groups were categorized based on age and grouped according to statistical significance values. The reference values for the different groups were determined using the Bhattacharya and Hoffmann methods. RESULTS: Vitamin B1 and B6 values and folate (vitamin B9) levels between the sexes were statistically significantly increased in the group aged 0 to 10 years. Likewise, we witnessed a similar increase in vitamin B12 levels in the group aged 0 to 5 years. However, low vitamin B6 levels (P <.001) were detected in nongeriatric patients (aged 0-60 years), and the reference intervals (3.4-41.9 µg/L) also were significantly different from those in the geriatric group (aged 61-100 years; 2.0-29.4 µg/L). CONCLUSION: A lower vitamin B6 reference limit allows detection of subclinical vitamin deficiency more precisely in the geriatric group; respective reference intervals should be revised accordingly.

Vitamin B1 interpretation: Erroneous higher levels in non-anemic populations.

OBJECTIVES: The aims of this study were to underline the interpretation of vitamin B1 and to evaluate whether differences in hemoglobin (Hb) levels and sex effect vitamin B1 results. METHODS: Simultaneously, whole blood vitamin B1 and complete blood count were determined in 2238 individuals. Groups were categorized on the basis of sex and Hb levels. Significance and correlation between groups and reference intervals of the study group were determined. RESULTS: There was an 8.4% (P < 0.001) difference between vitamin B1 levels of men and women, whereas the ratio of vitamin B1 to Hb showed a 0.12% (P = 0.921) difference. The reference interval for the ratio of vitamin B1 to Hb was 268 to 675 ng/g Hb. CONCLUSION: Vitamin B1 concentrations >48 µg/L should be interpreted with Hb levels to avoid postanalytical errors that mask deficiency. Therefore, in comparative studies, researchers need to pay attention to eliminate the effect of Hb on whole blood vitamin B1 levels.

Technical and diagnostic performance of a new fully automated immunoassay for the determination of intact fibroblast growth factor 23 (FGF23).

There is growing interest in measuring plasma fibroblast growth factor 23 (FGF23) concentrations in a number of clinical settings. However, a reliable assay with acceptable performance is lacking. Plasma samples of healthy adults and patients with different stages of chronic kidney disease (CKD) were used to compare the precision, recovery, linearity and the pre-analytical stability characteristics of a new fully automated FGF23 (intact) assay with a commercially available FGF23 (intact) ELISA. Method agreement was evaluated, reference and stage-specific ranges for kidney disease were established. Other biomarkers relevant for CKD were measured and compared with the FGF23 assays. The fully automated FGF23 (intact) assay demonstrated superior performance compared with the ELISA. A marked positive proportional bias was detected relative to the ELISA assay readout, especially in samples of higher concentration of patients undergoing hemodialysis. Overall, the method comparison revealed a poor degree of correlation. A significant inverse correlation was found between the glomerular filtration rate and both FGF23 assays (both p < .001). Regression analysis revealed that both assays are suitable to predict progression of CKD. A positive correlation was found between FGF23 and phosphate, parathyroid hormone (PTH) and vitamin D, 25(OH)D and 1,25(OH)2D-total assays, respectively. Cutoff points between different stages of CKD were calculated by receiver operator characteristic analysis. The fully automated assay displayed an improved discrimination compared with the ELISA, especially in mild to moderate kidney disease. The new fully automated FGF23 (intact) assay demonstrates excellent analytical performance data and represents a robust, fast and precise alternative to manual FGF23 testing.

Cross-method comparison of serum androstenedione measurement with respect to the validation of a new fully automated chemiluminescence immunoassay.

OBJECTIVES: Androstenedione is an androgen produced as an intermediate product of the biosynthesis of testosterone and estradiol in testicles, ovaries and also in the adrenal cortex. Measurement is used for diagnosing and differentiating hirsutism and virilisation, enzyme deficiencies of the steroid hormone biosynthesis, and in suspicion of androgen-producing tumors. METHODS: Specimens included de-identified residual serum specimens submitted for routine testing and banked adult and pediatric sera. Samples were measured with tandem mass spectrometry, two automated immunoassays, the newly developed DiaSorin LIAISON androstenedione assay, the Immulite assay, and a radioimmunoassay (Beckman Coulter) according to manufacturer's protocols. All methods were correlated, and the analytical sensitivity, linearity and imprecision of each assay determined. Diagnostic accuracy with respect to detection of PCOS in women was evaluated by verifying the respective reference ranges of the different assays and receiver operating characteristic (ROC) curve analysis. RESULTS: Due to the methodology, LC-MS/MS demonstrated the highest analytical specificity, good performance and excellent diagnostic accuracy. The best agreement was found with the LIAISON chemiluminescent immunoassay method. Due to its lower analytical sensitivity, the measured values in children were often outside the measuring range. Although, the coefficient of correlation between LC-MS/MS and the Beckman Coulter radioimmunoassay was lower, the assay demonstrated the best analytical sensitivity and a similar diagnostic accuracy in adults. The Immulite androstenedione chemiluminescent immunoassay showed the poorest performance and was not interchangeable with the other assays. CONCLUSIONS: These data suggest the LIAISON androstenedione assay may be a suitable alternative for the measurement of androstenedione in serum of adult patients with all advantages of a fully automated assay.

Lipocalin-2 in Fructose-Induced Fatty Liver Disease.

The intake of excess dietary fructose most often leads to non-alcoholic fatty liver disease (NAFLD). Fructose is metabolized mainly in the liver and its chronic consumption results in lipogenic gene expression in this organ. However, precisely how fructose is involved in NAFLD progression is still not fully understood, limiting therapy. Lipocalin-2 (LCN2) is a small secreted transport protein that binds to fatty acids, phospholipids, steroids, retinol, and pheromones. LCN2 regulates lipid and energy metabolism in obesity and is upregulated in response to insulin. We previously discovered that LCN2 has a hepatoprotective effect during hepatic insult, and that its upregulation is a marker of liver damage and inflammation. To investigate if LCN2 has impact on the metabolism of fructose and thereby arising liver damage, we fed wild type and Lcn2-/- mice for 4 or 8 weeks on diets that were enriched in fructose either by adding this sugar to the drinking water (30% w/v), or by feeding a chow containing 60% (w/w) fructose. Body weight and daily intake of food and water of these mice was then measured. Fat content in liver sections was visualized using Oil Red O stain, and expression levels of genes involved in fat and sugar metabolism were measured by qRT-PCR and Western blot analysis. We found that fructose-induced steatosis and liver damage was more prominent in female than in male mice, but that the most severe hepatic damage occurred in female mice lacking LCN2. Unexpectedly, consumption of elevated fructose did not induce de novo lipogenesis or fat accumulation. We conclude that LCN2 acts in a lipid-independent manner to protect the liver against fructose-induced damage.

Analytical evaluation of the novel soluble fms-like tyrosine kinase 1 and placental growth factor assays for the diagnosis of preeclampsia.

OBJECTIVES: Performance evaluation of the novel BRAHMS KRYPTOR soluble fms-like tyrosine kinase 1 (sFlt-1) and placental growth factor (PlGF) assays. DESIGN AND METHODS: Intra- and inter-assay imprecision, functional sensitivity, linearity in dilution, method comparison, and diagnostic capacity were evaluated. RESULTS: Intra-assay coefficient of variations (CVs) were between 1.1% and 5.3% and inter-assay CVs between 3.9% and 11.1%. Functional sensitivity was 6.7ng/L for PlGF and 34ng/L for sFlt-1, respectively. The linearity in dilution was excellent (r>0.995) in the assay-specific relevant range of concentration. The KRYPTOR assay correlated well with the Elecsys sFlt-1 (r=0.996), Elecsys PlGF (r=0.990) and the Elecsys sFlt-1/PlGF ratio (r=0.947) with partially high mean bias values. The optimal cut points for diagnosis of preeclampsia were calculated for KRYPTOR assays at: 60.5ng/L (PlGF), 4725ng/L (sFlt-1), and 99.2 (sFlt-1/PlGF ratio) which were different with the corresponding Elecsys cut points. Nevertheless, the sensitivity, specificity, positive predictive values (PPVs), negative predictive values (NPVs), and areas under the curves (AUCs) were completely comparable in both assay platforms, even when applying the standard cut-off of 85 for sFlt-1/PlGF ratio or gestational age specific "rule in-rule-out" cut-offs for early and late onset preeclampsia. CONCLUSION: The new BRAHMS KRYPTOR sFlt-1 and PlGF immunoassay show excellent precision and reliability. The assay results and the diagnostic capacity were highly comparable to established fully automated immunoassays (Elecsys). Hence, sFlt-1/PlGF ratio generated on KRYPTOR immunoassay platform should be suitable for diagnosing preeclampsia in clinical routine laboratory.

Performance of the two new fully automated anti-Müllerian hormone immunoassays compared with the clinical standard assay.

STUDY QUESTION: How do the two new fully automated anti-Müllerian hormone (AMH) assays released in September 2014 by two different diagnostic companies perform compared with the clinical standard assay, namely the AMH Gen II enzyme-linked immunosorbent assay (ELISA)? SUMMARY ANSWER: Both fully automated AMH assays perform in a nearly identical fashion compared with the AMH Gen II assay, with a higher analytical sensitivity. WHAT IS KNOWN ALREADY: Owing to the lack of standardization, the results of AMH ELISA assays are sometimes difficult to compare. The BCI AMH Gen II assay became the clinical reference assay over the last few years. Two newly developed fully automated, highly sensitive AMH immunoassays, based on the AMH Gen II antibody composition have become available since September 2014. STUDY DESIGN, SIZE, DURATION: Previously characterized serum samples from 155 women were used to measure AMH with the three immunoassays, focusing on the aspect of predicting ovarian reserve. PARTICIPANTS/MATERIALS, SETTING, METHODS: Samples from 94 women with an unfilled desire for a child diagnosed as infertile/subfertile, 29 samples women with polycystic ovary syndrome and 32 women approaching menopause were included to the study. The precision and the linearity in dilutions of the two new AMH assays were determined and the assay results were compared with the clinical reference (the modified version of the BCI AMH Gen II assay) and to the antral follicle counts of the study participants. Cutoff values for the discrimination between each of two predefined groups were calculated using receiver operating characteristic analysis. MAIN RESULTS AND THE ROLE OF CHANCE: The performance evaluation of the fully automated AMH assays resulted in a within-run and intermediate precision of 0.9-1.9% and 2.5-6.5% with the one and 0.9-3.6% or 4.4-10.7% with the other immunoassay, respectively. Pearson's coefficient of correlation was 0.991 for the method comparison between both assays with a bias of 0.003 ng/ml and a slope of 0.97. The discrimination of the new immunoassays between subfertile women and women approaching menopause was significantly better compared with the BCI Gen II assay (87.5 versus 68.8%, P < 0.05). LIMITATIONS, REASONS FOR CAUTION: Owing to the low number of study subjects in each group, the results have to be confirmed in further studies. WIDER IMPLICATIONS OF THE FINDINGS: The findings of the study are in good agreement with studies that used the Ultra Sensitivite AMH and the pico AMH ELISA assays. The application of AMH measurement onto an automated immunoassay platform is a major step forward, allowing health care providers rapid access to the AMH result and facilitating the adoption of AMH measurement into daily clinical practice. STUDY FUNDING/COMPETING INTERESTS: We declare no financial relationships or competing interests.