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1.
J Med Virol ; 93(4): 2039-2045, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32986242

RESUMO

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.


Assuntos
Distribuição por Idade , COVID-19/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Alemanha , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Pandemias , Estudos Retrospectivos , Adulto Jovem
2.
J Clin Lab Anal ; 35(9): e23940, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34346119

RESUMO

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.


Assuntos
Biotina/química , Erros de Diagnóstico/prevenção & controle , Imunoensaio/normas , Hormônios Tireóideos/sangue , Artefatos , Biotina/administração & dosagem , Biotina/sangue , Voluntários Saudáveis , Humanos , Testes de Função Tireóidea
3.
Gastroenterology ; 157(3): 705-719.e18, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31121167

RESUMO

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.


Assuntos
Fígado Gorduroso/etiologia , Metabolismo dos Lipídeos , Cirrose Hepática/etiologia , Fígado/metabolismo , Mutação , Deficiência de alfa 1-Antitripsina/complicações , alfa 1-Antitripsina/genética , Adulto , Fatores Etários , Idoso , Animais , Estudos de Casos e Controles , Técnicas de Imagem por Elasticidade , Europa (Continente) , Fígado Gorduroso/sangue , Fígado Gorduroso/diagnóstico , Feminino , Predisposição Genética para Doença , Homozigoto , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Testes de Função Hepática , Masculino , Camundongos Transgênicos , Pessoa de Meia-Idade , Fenótipo , Fatores de Risco , Fatores Sexuais , Deficiência de alfa 1-Antitripsina/diagnóstico , Deficiência de alfa 1-Antitripsina/enzimologia , Deficiência de alfa 1-Antitripsina/genética
4.
Clin Endocrinol (Oxf) ; 93(1): 44-51, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32160329

RESUMO

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.


Assuntos
Resistência à Insulina , Síndrome do Ovário Policístico , Hormônio Antimülleriano , Peptídeo C , Feminino , Glucose , Humanos , Fenótipo , Estudos Retrospectivos
5.
Clin Chem Lab Med ; 58(8): 1291-1301, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32069226

RESUMO

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.


Assuntos
Fatores Etários , Hormônio Antimülleriano/sangue , Síndrome do Ovário Policístico/diagnóstico , Adolescente , Adulto , Cromatografia Líquida/métodos , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Hormônio Luteinizante/sangue , Pessoa de Meia-Idade , Síndrome do Ovário Policístico/sangue , Valores de Referência , Espectrometria de Massas em Tandem/métodos , Testosterona/sangue , Adulto Jovem
6.
Clin Endocrinol (Oxf) ; 90(6): 827-833, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30868616

RESUMO

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.


Assuntos
Hormônio Antimülleriano/sangue , Hormônio Foliculoestimulante/sangue , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Luteinizante/sangue , Adolescente , Adulto , Criança , Feminino , Hormônio Liberador de Gonadotropina/fisiologia , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
7.
Reprod Biomed Online ; 39(6): 1017-1025, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31727499

RESUMO

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.


Assuntos
Infertilidade Feminina/sangue , Receptores de Peptídeos/sangue , Receptores de Fatores de Crescimento Transformadores beta/sangue , Adolescente , Adulto , Biomarcadores/sangue , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/diagnóstico , Pós-Menopausa/sangue , Estudos Retrospectivos , Adulto Jovem
8.
Scand J Clin Lab Invest ; 78(7-8): 584-590, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30380963

RESUMO

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.


Assuntos
Fatores de Crescimento de Fibroblastos/sangue , Imunoensaio/métodos , Ensaio de Imunoadsorção Enzimática , Fator de Crescimento de Fibroblastos 23 , Humanos , Insuficiência Renal Crônica/sangue
9.
Hum Reprod ; 30(8): 1918-26, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26093541

RESUMO

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.


Assuntos
Hormônio Antimülleriano/sangue , Imunoensaio/métodos , Adulto , Feminino , Humanos , Infertilidade/sangue , Pessoa de Meia-Idade , Síndrome do Ovário Policístico/sangue , Adulto Jovem
10.
Clin Chem Lab Med ; 53(5): 761-70, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25274943

RESUMO

BACKGROUND: Previous studies have shown that the measurement of vitamin D and its derivatives, especially its active metabolite 1α, 25-dihydroxy-vitamin D [1,25(OH)2D], is highly complex and prone to analytical error. We have evaluated a new immunological method for detecting and quantifying of 1,25(OH)2D. This assay is fully automated, sensitive and uses a specific recombinant fusion protein for capturing of 1,25(OH)2D. The assay was originally developed by DiaSorin for the immunoassay analyzer LIAISON XL. METHODS: Performance data of this assay were determined including intra- and inter-assay precision, recovery, linearity, and limit of detection of the DiaSorin 1,25(OH)2D immunoassay on the LIAISON XL analyzer. Respective data were compared from two different liquid chromatography tandem mass spectrometry (LC-MS/MS) assays and a common radioimmunoassay (RIA) using clinical samples taken from patients suffering from vitamin D deficiency, chronic renal failure, biliary atresia, hyperparathyroidism, vitamin D-dependent rickets or sarcoidosis, as well as from pregnant women and high-level athletes. RESULTS: The performance evaluation of 1,25(OH)2D resulted in an intra-assay and total imprecision correlation variant between 1.4% and 5.2% and 3.8%-7.1% with the new immunoassay and 3.5%-5.8% or 3.8%-7.5% with the LC-MS/MS method, respectively. Limits of detection and quantification of the immunoassay were 0.7 ng/L and 5.0 ng/L for the LIAISON XL immunoassay and 1.8 ng/L and 5.4 ng/L for the LC-MS/MS assay, respectively. Pearson's coefficients of correlation were 0.998 and 0.952 for method comparison to different established LC-MS/MS methods. Linear regression according to Passing and Bablok showed larger deviations to the RIA (slopes 0.64-0.97, coefficients of correlation 0.822-0.823). CONCLUSIONS: The DiaSorin LIAISON XL 1,25(OH)2D immunoassay appears to have improved comparability to LC-MS/MS with low imprecision and limits of detection. The assay time of 65 min, the small sample volume required (75 µL) and the throughput of 90 tests/hour without manually handling time for extraction and purification procedures is superior to the LC-MS/MS method.


Assuntos
Análise Química do Sangue/métodos , Vitamina D/análogos & derivados , Automação , Humanos , Imunoensaio , Modelos Lineares , Medições Luminescentes , Fatores de Tempo , Vitamina D/sangue
11.
Clin Lab ; 60(10): 1641-51, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25651709

RESUMO

BACKGROUND: The aim of the present study was to evaluate the technical performance of a new immunoassay for the detection of human growth hormone. METHODS: The Elecsys growth hormone (GH) Immunoassay which is composed of two hGH specific antibodies, one biotinylated monoclonal Ab and one polyclonal Ab coupled with a ruthenium complex, was compared with three currently available automated GH immunoassays. RESULTS: The performance evaluation resulted in an interassay and total imprecision CV between 0.6-1.7% and 1.7-4.1%, respectively. Using the 20% CV criteria, the functional sensitivity was found at 0.05 µg/L. Pearson's coefficients of correlation were > 0.98 for method comparison to three established automated GH reagents (A-C). Linear regression according to Passing and Bablok showed larger deviations to reagent A (slopes 1.36-1.44), while closer agreement was obtained with reagent B and C. Diagnostic results obtained with the Elecsys® hGH assay in various stimulation and suppression tests of patients with growth hormone deficiency and acromegaly compared to healthy controls were in close agreement to established reagents demonstrating high sensitivity and specificity for the diagnosis of growth hormone disorders. CONCLUSIONS: The evaluation of the GH immunoassay generated homogeneous performance data but the comparison with three established full automated hGH assays demonstrated a considerable degree of variability suggesting assay specific interpretation in the provocation testing of growth hormone disorders. Obviously, such discrepancies limit the applicability of consensus guidelines. Nevertheless, because of its excellent reproducibility, robustness and the short assay time, the new automated hGH assay represents a major improvement in endocrine diagnosis and treatment in clinical practice.


Assuntos
Hormônio do Crescimento Humano/análise , Imunoensaio , Adolescente , Adulto , Fatores Etários , Idoso , Automação Laboratorial , Calibragem , Criança , Pré-Escolar , Feminino , Humanos , Imunoensaio/normas , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Padrões de Referência , Reprodutibilidade dos Testes , Fatores Sexuais , Adulto Jovem
12.
Cell Death Discov ; 10(1): 94, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388533

RESUMO

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.

13.
J Med Virol ; 85(8): 1362-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23765774

RESUMO

Routine screening of patients at risk of hepatitis C virus (HCV) infection has become a priority given recent improvements in therapeutic options and the asymptomatic nature of most chronic infections. The aim of this study was to evaluate the performance of the Elecsys® Anti-HCV II assay, a new qualitative antibody immunoassay, compared with currently available assays, and assess its suitability for routine diagnostic testing. The sensitivity of the Elecsys® Anti-HCV II, ARCHITECT® Anti-HCV, AxSYM® HCV 3.0, PRISM® HCV, Vitros® ECi Anti-HCV, Elecsys® Anti-HCV, and ADVIA Centaur® HCV assays was compared using commercially available seroconversion panels and samples from patients known to be HCV positive and infected with HCV genotypes 1-6. Specificity was investigated using samples from blood donors, unselected hospitalized patients, and patients with potential cross-reacting factors or from high-risk groups. The Elecsys® Anti-HCV II assay detected more positive bleeds than the comparator assays, was more sensitive in recognizing early HCV infection, and correctly identified all 765 samples known to be HCV positive, regardless of genotype. The overall specificity of the Elecsys(®) Anti-HCV II assay was 99.84% (n=6,850) using blood donor samples, 99.66% (n=3,922) using samples from unselected hospitalized patients, and 99.66% (n=2,397) using samples from patients with potentially cross-reacting factors or from high-risk groups. The specificity of the Elecsys® Anti-HCV II assay was superior or equal to the comparator assays. In conclusion, the Elecsys® Anti-HCV II assay is a sensitive and specific assay suitable for routine use in the reliable detection of anti-HCV antibodies.


Assuntos
Técnicas de Laboratório Clínico/métodos , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/sangue , Hepatite C/diagnóstico , Feminino , Humanos , Imunoensaio/métodos , Masculino , Gravidez , Sensibilidade e Especificidade
14.
Metabolites ; 12(10)2022 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-36295802

RESUMO

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.

15.
Pract Lab Med ; 26: e00244, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34337125

RESUMO

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.

16.
World J Clin Cases ; 9(6): 1386-1393, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33644206

RESUMO

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.

17.
Cells ; 9(6)2020 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-32481590

RESUMO

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.


Assuntos
Deleção de Genes , Inflamassomos/metabolismo , Fígado/lesões , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Perilipina-5/metabolismo , Animais , Ácido Araquidônico/metabolismo , Dieta Hiperlipídica , Estresse do Retículo Endoplasmático , Feminino , Hepatócitos/metabolismo , Hepatócitos/patologia , Inflamação/patologia , Metabolismo dos Lipídeos , Fígado/patologia , Fígado/ultraestrutura , Camundongos Endogâmicos C57BL , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/ultraestrutura , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Perilipina-5/deficiência
18.
Clin Endocrinol (Oxf) ; 71(4): 566-73, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19170704

RESUMO

BACKGROUND: Most recently, a new rapid and fully automated electrochemiluminescence immunoassay for the determination of TSH receptor autoantibodies (TRAb) based on the ability of TRAb to inhibit the binding of a human thyroid-stimulating monoclonal antibody (M22) has been established. OBJECTIVE: To evaluate this assay system in clinical routine based on an international multicentre trial and to compare the results with other established TRAb assays. PATIENTS AND MEASUREMENTS: Totally 508 Graves' disease (GD), 142 autoimmune thyroiditis, 107 subacute thyroiditis, 109 nonautoimmune nodular goitre, 23 thyroid cancer patients and 446 normal controls were retrospectively evaluated. RESULTS: ROC plot analysis revealed an area under curve of 0.99 (95% CI: 0.99-1.0) indicating a high assay sensitivity and specificity. The highest sensitivity (99%) and specificity (99%) was seen at a cut-off level of 1.75 IU/l. Here, the calculated positive predictive value was 95%, whereas the negative predictive value was 100%. Applying the ROC plot-derived cut-off of 1.75 IU/l we found a sensitivity for TRAb positivity within the group of newly diagnosed GD patients of 97% which is in accordance to the sum of different nonautomated porcine TSH receptor-based assays with a sensitivity of 94% indicating an excellent analytical performance of the new assay format. Detailed comparison of the automated and the sum of manual assays revealed a near identical specificity. CONCLUSION: Our results demonstrate that this new assay system has a high sensitivity for detecting GD and specificity for discriminating from other thyroid diseases. This assay may represent the future technology for rapid fully automated TRAb detection.


Assuntos
Autoanticorpos/análise , Doença de Graves/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Autoanálise , Criança , Feminino , Doença de Graves/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Receptores da Tireotropina/análise , Receptores da Tireotropina/imunologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Doenças da Glândula Tireoide/diagnóstico , Doenças da Glândula Tireoide/imunologia , Neoplasias da Glândula Tireoide/diagnóstico , Tireoidite Autoimune/diagnóstico
19.
Clin Lab ; 55(7-8): 267-73, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19894405

RESUMO

Roche Diagnostics has developed two new rapid and fully automated assays for the detection of Anti-Toxo-IgG and Toxo-IgM antibodies from human sera and plasma. The performance evaluation of the Elecsys Toxo IgG resulted in a sensitivity of 100% and a specificity of 99.91% showing that this assay allows a very sensitive and specific detection of Toxo IgG antibodies with an excellent discrimination of positive and negative results. The performance evaluation of the Elecsys Toxo IgM assay revealed a sensitivity of 100% and a specificity of 99.11% after resolution. Less reactivity towards persistent Toxo IgM antibodies in samples from Toxoplasma infections > 3 months was found with Elecsys Toxo IgM. The performance evaluation data demonstrate that the Elecsys Toxo IgG and Elecsys Toxo IgM assays are reliable tools in routine diagnostics of Toxoplasma infections with the additional advantage of a high throughput on fully automated analyzers MODULAR ANALYTICS Serum Work Area.


Assuntos
Imunoensaio/métodos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Toxoplasma/imunologia , Toxoplasmose/imunologia , Animais , Anticorpos Antiprotozoários/sangue , Antígenos de Superfície/sangue , Antígenos de Superfície/imunologia , Automação/métodos , Calibragem , Humanos , Sensibilidade e Especificidade , Toxoplasmose/sangue , Toxoplasmose/diagnóstico
20.
Lab Med ; 50(1): 54-63, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30085194

RESUMO

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.


Assuntos
Análise Química do Sangue/normas , Complexo Vitamínico B/sangue , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Fatores Sexuais , Complexo Vitamínico B/normas
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