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BACKGROUND: While childhood asthma prevalence is rising in Westernized countries, farm children are protected. The mitogen-activated protein kinase (MAPK) pathway with its negative regulator dual-specificity phosphatase-1 (DUSP1) is presumably associated with asthma development. OBJECTIVES: We aimed to investigate the role of MAPK signaling in childhood asthma and its environment-mediated protection, including a representative selection of 232 out of 1062 children from two cross-sectional cohorts and one birth cohort study. METHODS: Peripheral blood mononuclear cells (PBMC) from asthmatic and healthy children were cultured upon stimulation with farm-dust extracts or lipopolysaccharide. In subgroups, gene expression was analyzed by qPCR (PBMCs, cord blood) and NanoString technology (dendritic cells). Protein expression of phosphorylated MAPKs was measured by mass cytometry. Histone acetylation was investigated by chromatin immunoprecipitation. RESULTS: Asthmatic children expressed significantly less DUSP1 (p = .006) with reduced acetylation at histone H4 (p = .012) compared with healthy controls. Farm-dust stimulation upregulated DUSP1 expression reaching healthy levels and downregulated inflammatory MAPKs on gene and protein levels (PBMCs; p ≤ .01). Single-cell protein analysis revealed downregulated pMAPKs upon farm-dust stimulation in B cells, NK cells, monocytes, and T-cell subpopulations. CONCLUSION: Lower DUSP1 baseline levels in asthmatic children and anti-inflammatory regulation of MAPK in several immune cell types by farm-dust stimulation indicate a regulatory function for DUSP1 for future therapy contributing to anti-inflammatory characteristics of farming environments.
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Asma , Leucócitos Mononucleares , Asma/epidemiologia , Asma/genética , Criança , Estudos de Coortes , Estudos Transversais , Humanos , Proteínas Quinases Ativadas por MitógenoRESUMO
BACKGROUND: Liver biotransformation is the major route for drug metabolism in humans, often catalysed by cytochrome P450 (CYP) enzymes. This first-pass effect can lead to hepatotoxicity and influences the bioavailability of drugs. OBJECTIVE: We aimed to establish in vitro culture systems simulating the liver first-pass to study effects of the proteasome inhibitor MG-132 simultaneously on hepatocytes and cancer cells. METHODS: The first-pass effect was simulated by conditioned medium transfer (CMT) from pre-treated HepG2 CYP3A4-overexpressing cells to either pancreatic cancer cell line PANC-1 or primary colon cancer cells, and by indirect co-culture (CC) of liver and cancer cells in a shared medium compartment. Experimental proteasome inhibitor MG-132 was used as test substance as it is detoxified by CYP3A4. RESULTS: Cancer cells showed higher viabilities in the first-pass simulation by CMT and CC formats when compared to monocultures indicating effective detoxification of MG-132 by HepG2 CYP3A4-overexpressing cells. HepG2-CYP3A4 cells showed reduced viabilites after treatment with MG-132. CONCLUSIONS: We successfully established two different culture systems to simulate the liver first-pass effect in vitro. Such systems easily allow to study drug effects simultaneously on liver and on target cancer cells. They are of great value in pre-clinical cancer research, pharmaceutical research and drug development.
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Citocromo P-450 CYP3A , Leupeptinas , Neoplasias , Humanos , Células Hep G2 , Inibidores de Proteassoma/farmacologia , Fígado , Sistema Enzimático do Citocromo P-450/metabolismo , BiotransformaçãoRESUMO
BACKGROUND: Cushing's syndrome (CS) can be difficult to diagnose. A timely diagnosis, however, is the cornerstone for targeted treatment, to reduce morbidity and mortality. One reason for the difficulties to identify early on patients with CS might be the presence of a mild phenotype. The aim of the study was to classify the phenotypic landscape of CS. We studied patients with overt CS and mild autonomous cortisol secretion (MACS). METHOD: The study was part of the German Cushing's registry. Patients were prospectively included at time of diagnosis and the number of comorbidities and clinical signs and symptoms were assessed in a standardized fashion. One hundred twenty-nine patients with CS (pituitary CS, n = 85, adrenal CS, n = 32, ectopic CS, n = 12, respectively) and 48 patients with MACS were included. Patients with clinical signs and/or comorbidities typical for CS and at least 2 pathological screening tests were classified as having CS. Patients with a 1â mg low-dose-dexamethasone-suppression test above 1.8â µg/dL without being clinically overt CS were classified as having MACS. RESULTS: On average, patients with CS had 2 comorbidities (range 1-3) at time of diagnosis (pituitary CS: 2 [1-3], adrenal CS: 3 [2-4], ectopic CS: 3 [2-4]). Patients with MACS, however, had 3 comorbidities (range 2-3). Hypertension was the most common comorbidity in all subtypes of CS (78%-92%) and in patients with MACS (87%). Of a total of 11 clinical signs, patients with CS had on average 5 with 28% of patients having between 0 and 3 clinical signs, 50% 4-7 signs, and 22% more than 7 clinical signs. Patients with MACS had on average 2 clinical signs (range 1-3) at time of diagnosis. CONCLUSION: The phenotypic landscape of CS is quite variable. The frequency of comorbidities is similar between patients with CS and MACS. A relevant number of patients with overt CS have just a few clinical signs. There is also an overlap in frequency of symptoms and clinical signs between patients with CS and MACS. According to the current guidelines, 96% of our patients with MACS fall into the category "consideration of adrenalectomy". This should be kept in mind when making treatment decisions in the latter group of patients.
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Síndrome de Cushing , Hidrocortisona , Humanos , Síndrome de Cushing/diagnóstico , Síndrome de Cushing/epidemiologia , Síndrome de Cushing/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Hidrocortisona/sangue , Hidrocortisona/metabolismo , Adulto , Idoso , Adulto Jovem , Estudos Prospectivos , Sistema de Registros , Comorbidade , Alemanha/epidemiologia , AdolescenteRESUMO
Advanced paternal age increases the risk of transmitting de novo germline mutations, particularly missense mutations activating the receptor tyrosine kinase (RTK) signalling pathway, as exemplified by the FGFR3 mutation, which is linked to achondroplasia (ACH). This risk is attributed to the expansion of spermatogonial stem cells carrying the mutation, forming sub-clonal clusters in the ageing testis, thereby increasing the frequency of mutant sperm and the number of affected offspring from older fathers. While prior studies proposed a correlation between sub-clonal cluster expansion in the testis and elevated mutant sperm production in older donors, limited data exist on the universality of this phenomenon. Our study addresses this gap by examining the testis-expansion patterns, as well as the increases in mutations in sperm for two FGFR3 variants-c.1138G>A (p.G380R) and c.1948A>G (p.K650E)-which are associated with ACH or thanatophoric dysplasia (TDII), respectively. Unlike the ACH mutation, which showed sub-clonal expansion events in an aged testis and a significant increase in mutant sperm with the donor's age, as also reported in other studies, the TDII mutation showed focal mutation pockets in the testis but exhibited reduced transmission into sperm and no significant age-related increase. The mechanism behind this divergence remains unclear, suggesting potential pleiotropic effects of aberrant RTK signalling in the male germline, possibly hindering differentiation requiring meiosis. This study provides further insights into the transmission risks of micro-mosaics associated with advanced paternal age in the male germline.
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Acondroplasia , Sêmen , Idoso , Humanos , Masculino , Acondroplasia/genética , Mutação , Receptores Proteína Tirosina Quinases/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Espermatozoides/metabolismo , Testículo/metabolismo , Senescência CelularRESUMO
INTRODUCTION: Endogenous hypercortisolism presents with variable phenotypes. Etiological factors accounting for the level of hypercortisolism or varying severity of associated comorbidities are lacking. Recently, the adrenal ATP-binding cassette B1 (ABCB1) gene was identified as a modulator of glucocorticoid secretion. OBJECTIVE: To evaluate the effect of ABCB1 polymorphism rs2032582 on steroid metabolome and clinical phenotypes in patients with endogenous hypercortisolism. METHODS: In this cross-sectional cohort study, 137 patients prospectively enrolled in the German Cushing's registry were included (41 with ACTH-producing pituitary adenoma, 21 with cortisol-producing adrenal adenoma, and 75 with excluded hypercortisolism). In all patients, ABCB1 polymorphism was analyzed using a TaqMan genotyping assay, glucocorticoid metabolite excretion in 24-hour urine samples was analyzed by gas chromatography-mass spectrometry, and the clinical phenotype was assessed systematically. RESULTS: In patients with cortisol-producing adrenal adenomas, but not in patients with ACTH-producing pituitary adenomas, homozygous major allele GG of ABCB1 polymorphism rs2032582 was associated with higher overall cortisol metabolite secretion (median 13515 [IQR 10347; 25669] µg/24h vs. 9645 [6146; 10732] µg/24h in minor homo- and heterozygotes, p=0.036) and elevated major cortisol metabolites αTHF, THF and THE (9339 [6929; 17789] µg/24h vs. 6288 [4184; 7455] µg/24h, p=0.045). Moreover, these patients showed higher mean arterial pressure (116 [111; 131] mmHg in major homozygotes vs. 105 [96; 112] mmHg in minor homo- and heterozygotes, p=0.036). CONCLUSION: The genotype of drug transporter gene ABCB1 rs2032582 polymorphism is associated with the degree of cortisol metabolite secretion in cortisol-producing adrenal adenomas and could, therefore, represent a modifier of disease severity in this context.
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BACKGROUND: Normalization of hypercortisolism is essential to reduce morbidity and mortality in patients with Cushing's syndrome (CS). The aim of this analysis was to assess biochemical control rates in patients with Cushing's disease (CD), ectopic Cushing's syndrome (ECS) and adrenal Cushing's syndrome (ACS). METHODS: Patients with confirmed CS (n= 296) treated in a single tertiary care center were retrospectively analysed (185 CD, 27 ECS, 84 uni- and bilateral ACS). RESULTS: Firstline treatment led to biochemical control in 82% of the patients. Time to biochemical control (median, IQR) was longer in CD (11.0 weeks, 5.6-29.8; p< 0.05) than in ACS (7.7 weeks, 4.1-17.1) and ECS (5.6 weeks, 4.1-23.3). Disease persistence or recurrence after first-line therapy was observed more often in CD (24% and 18%; p< 0.05) than in ECS (15% and 15%) and ACS (6% and 4%). Total time in hypercortisolism since diagnosis was significantly shorter in patients with CD diagnosed since 2013, after specialized patient care was implemented, compared to patients diagnosed before 2013 (13.5 weeks, vs. 26.1 weeks; p< 0.0070). Control of hypercortisolism at last follow up (76 months, 38-163) was achieved in 94% of patients with ACS, 100% of patients with ECS and 92% of patients with CD. CONCLUSIONS: Biochemical control can be achieved in most patients with different subtypes of CS within a reasonable time frame. Control of hypercortisolism has improved over time.
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BACKGROUND: Secondary hypogonadism (SH) is common in men with Cushing's syndrome (CS), but its impact on comorbidities is largely unknown and longitudinal data are scarce. If SH also affects men with mild autonomous cortisol secretion (MACS) is unknown. METHODS: We included 30 treatment-naïve adult men with CS and 17 men with MACS diagnosed since 2012. Hypogonadism was diagnosed based on total testosterone (TT) concentrations < 10.4 nmol/L and age-specific cut-offs. Outcomes were compared to age- and BMI-matched controls. In 20 men in remission of CS, a longitudinal analysis was conducted at 6, 12, and 24 months. RESULTS: Men with CS had significantly lower concentrations of TT, bioavailable T, and free T compared to controls (P < .0001) with lowest concentrations in ectopic CS. Likewise, TT was lower in men with MACS compared to controls. At baseline, 93% of men with CS and 59% of men with MACS had SH. Testosterone correlated negatively with late night salivary cortisol and serum cortisol pre- and post-1 mg dexamethasone suppression test. Following successful surgery, TT increased significantly (P = .001), normalising within 6 months. Despite normalisation, several RBC parameters remained lower in men with CS even 2 years after successful surgery. CONCLUSIONS: Secondary hypogonadism is common in men with CS and MACS but usually reversible after successful surgery. The persisting changes observed in RBC parameters need to be further investigated in larger cohorts and longer follow-up durations.
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Síndrome de Cushing , Hidrocortisona , Hipogonadismo , Testosterona , Humanos , Masculino , Hipogonadismo/epidemiologia , Hipogonadismo/metabolismo , Hipogonadismo/sangue , Síndrome de Cushing/epidemiologia , Síndrome de Cushing/metabolismo , Síndrome de Cushing/complicações , Síndrome de Cushing/sangue , Hidrocortisona/sangue , Hidrocortisona/metabolismo , Pessoa de Meia-Idade , Adulto , Testosterona/sangue , Prevalência , Estudos Longitudinais , Resultado do Tratamento , IdosoRESUMO
CONTEXT: Sexual dimorphism has direct consequences on the incidence and survival of cancer. Early and accurate diagnosis is crucial to improve prognosis. OBJECTIVE: This work aimed to characterized the influence of sex and adrenal asymmetry on the emergence of adrenal tumors. METHODS: We conducted a multicenter, observational study involving 8037 patients with adrenal tumors, including adrenocortical carcinoma (ACC), aldosterone-producing adenoma (APA), cortisol-secreting adrenocortical adenomas (CSAs), non-aldosterone-producing adrenal cortical adenoma (NAPACA), pheochromocytoma (PCC), and neuroblastoma (NB), and investigated tumor lateralization according to sex. Human adrenal tissues (n = 20) were analyzed with a multiomics approach that allows determination of gene expression, catecholamine, and steroid contents in a single sample. In addition, we performed a literature review of computed tomography and magnetic resonance imaging-based studies examining adrenal gland size. RESULTS: ACC (n = 1858); CSA (n = 68), NAPACA (n = 2174), and PCC (n = 1824) were more common in females than in males (female-to-male ratio: 1.1:1-3.8:1), whereas NBs (n = 2320) and APAs (n = 228) were less prevalent in females (0.8:1). ACC, APA, CSA, NAPACA, and NB occurred more frequently in the left than in the right adrenal (left-to-right ratio: 1.1:1-1.8:1), whereas PCC arose more often in the right than in the left adrenal (0.8:1). In both sexes, the left adrenal was larger than the right adrenal; females have smaller adrenals than males. CONCLUSION: Adrenal asymmetry in both sexes may be related to the pathogenesis of adrenal tumors and should be considered during the diagnosis of these tumors.
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Neoplasias do Córtex Suprarrenal , Neoplasias das Glândulas Suprarrenais , Adenoma Adrenocortical , Carcinoma Adrenocortical , Feocromocitoma , Feminino , Humanos , Masculino , Corticosteroides , Neoplasias do Córtex Suprarrenal/genética , Glândulas Suprarrenais/diagnóstico por imagem , Glândulas Suprarrenais/metabolismo , Adenoma Adrenocortical/metabolismo , Aldosterona/metabolismo , Feocromocitoma/metabolismo , Caracteres SexuaisRESUMO
Cyclic Cushing's syndrome is a subentity of Cushing's syndrome in which phases of biochemical hypercortisolism (peaks) are followed by spontaneous periods of physiological or even hypocortisolaemic cortisol secretion (troughs). To identify common features of cyclic Cushing's syndrome, we systematically reviewed single case reports and case series in MEDLINE from database inception to Oct 10, 2022, and identified 707 articles, of which 149 articles were assessed for eligibility and 118 articles (covering 212 cases) were included in the analysis. Pituitary tumours accounted for 67% of cases of cyclic Cushing's syndrome (n=143), ectopic tumours for 17% (n=36), and adrenal tumours for 11% (n=23). Occult tumours accounted for 2% of cases (n=4), and 3% of cases were unclassified (n=6). We compared the clinical symptoms and comorbidities of patients with cyclic Cushing's syndrome with those of patients with non-cyclic Cushing's syndrome and observed no major difference. In adrenocorticotropic hormone (ACTH)-dependent cyclic Cushing's syndrome, bilateral inferior petrosal sinus sampling had a positive (ie, true pituitary) and negative (ie, true ectopic) predictive value of 100% when performed during periods of hypercortisolism, versus a positive predictive value of 73% and a negative predictive value of 86% when performed, irrespective of cortisolaemic status. Overall, 6% of patients (n=12) with cyclic Cushing's syndrome had unnecessary surgery due to misclassification. Remission rates were significantly lower and the time to remission significantly longer in patients with cyclic Cushing's syndrome compared with patients with non-cyclic Cushing's syndrome (p<0·001). Variations in biochemical test results due to unpredictable cycle duration and frequency might cause diagnostic challenges resulting in misdiagnoses and missed diagnoses.
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Síndrome de Cushing , Neoplasias Hipofisárias , Humanos , Síndrome de Cushing/diagnóstico , Síndrome de Cushing/etiologia , Hormônio Adrenocorticotrópico , Amostragem do Seio Petroso/efeitos adversos , Amostragem do Seio Petroso/métodos , Neoplasias Hipofisárias/diagnóstico , Valor Preditivo dos Testes , Diagnóstico DiferencialRESUMO
OBJECTIVE: Endogenous Cushing's syndrome (CS) is a severe condition, often diagnosed at a late stage. To reduce mortality, early diagnosis plays an important role. Two screening tools for early identification of patients with CS have been developed in multicentric cohorts, but have not yet been validated in cohorts with different geographic backgrounds. DESIGN: We validated the Spanish score published by Leon-Justel et al. in 2016 and the Italian score by Parasiliti-Caprino et al. published in 2021 in our cohort. METHODS: In the multicentric German Cushing registry, patients with confirmed and expected but ruled out Cushing's syndrome are prospectively diagnosed and followed up. We validated both scores in a cohort of 458 subjects: 176 patients with confirmed CS and 282 patients with suspected, but finally excluded CS. RESULTS: Using the Spanish score, 17.5% of our patients with proven CS biochemical screening would not have been recommended. This concerned patients with pituitary CS (22%) and with adrenal CS (10%). On the contrary, only 14% of patients without CS would have received a recommendation for biochemical screening. Using the Italian score, 29% of patients with proven CS were classified into the low-risk classes not recommended for biochemical screening. This mostly affected patients with adrenal (31%) and pituitary CS (30%). About 12% of subjects without CS would have received a biochemical screening recommendation. CONCLUSIONS: Both scores had limited sensitivity and high specificity in a German validation cohort. Further research is necessary to develop a screening score, which is effective in different healthcare systems and ethnicities.
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Síndrome de Cushing , Hipersecreção Hipofisária de ACTH , Humanos , Síndrome de Cushing/diagnóstico , Hidrocortisona , Medição de Risco , Alemanha/epidemiologiaRESUMO
IMPORTANCE: Endogenous Cushing's syndrome (CS) leads to profound immunosuppression. Successful surgery induces biochemical remission and reversal of immunosuppression, which is characterized by clinical signs of glucocorticoid withdrawal and associated with increased susceptibility to infections and thromboembolic complications. OBJECTIVE: We hypothesized that the glucocorticoid withdrawal phase is characterized by low-grade inflammation that may be related to patient-relevant outcomes. SETTING: In this retrospective observational study, we analyzed longitudinal data from 80 patients with CS prospectively enrolled in the German Cushing's registry between 2012 and 2021. All enrolled patients underwent successful surgery. In a second step, a case-control study was performed in 25 of the patients with age-, gender-, and body mass index-matched control patients in whom hypercortisolism was excluded. Analyses included the inflammatory markers C-reactive protein and interleukin-6, as well as body composition, muscle function testing, and quality-of-life questionnaires. The patients were studied during active CS and in the postoperative remission phase 1, 3, 6, 12, and 24 months after surgery. RESULTS: Compared with the preoperative phase and matched controls, patients with CS had increased systemic inflammatory markers in the early remission phase. One month following surgery, median (interquartile range) C-reactive protein was 0.48â mg dL-1 (0.14-0.90) vs 0.10â mg dL-1 (0.06-0.39) during active CS (P ≤ .001). Similarly, interleukin-6 1 month after surgery was 7.2â pg mL-1 (3.3-11.7) vs 1.7â pg mL-1 (1.5-2.5) during active CS (P ≤ .001). Obesity and hemoglobin A1c (HbA1c) were associated with increased inflammation levels. This proinflammatory state lasted until 1 year following surgery. Moreover, inflammatory markers during early remission showed an inverse correlation with long-term muscle function. CONCLUSIONS: The glucocorticoid withdrawal phase is associated with a low-grade inflammatory state, which is particularly pronounced in obese and hyperglycemic patients and related to lower muscle function.
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Síndrome de Cushing , Doenças Musculares , Humanos , Glucocorticoides , Síndrome de Cushing/diagnóstico , Estudos de Casos e Controles , Proteína C-Reativa , Interleucina-6 , Hidrocortisona , InflamaçãoRESUMO
Background: We performed a transcriptomic analysis of adrenal signaling pathways in various forms of endogenous Cushing's syndrome (CS) to define areas of dysregulated and druggable targets. Methodology: Next-generation sequencing was performed on adrenal samples of patients with primary bilateral macronodular adrenal hyperplasia (PBMAH, n=10) and control adrenal samples (n=8). The validation groups included cortisol-producing adenoma (CPA, n=9) and samples from patients undergoing bilateral adrenalectomy for Cushing's disease (BADX-CD, n=8). In vivo findings were further characterized using three adrenocortical cell-lines (NCI-H295R, CU-ACC2, MUC1). Results: Pathway mapping based on significant expression patterns identified PPARG (peroxisome proliferator-activated receptor gamma) pathway as the top hit. Quantitative PCR (QPCR) confirmed that PPARG (l2fc<-1.5) and related genes - FABP4 (l2fc<-5.5), PLIN1 (l2fc<-4.1) and ADIPOQ (l2fc<-3.3) - were significantly downregulated (p<0.005) in PBMAH. Significant downregulation of PPARG was also found in BADX-CD (l2fc<-1.9, p<0.0001) and CPA (l2fc<-1.4, p<0.0001). In vitro studies demonstrated that the PPARG activator rosiglitazone resulted in decreased cell viability in MUC1 and NCI-H295R (p<0.0001). There was also a significant reduction in the production of aldosterone, cortisol, and cortisone in NCI-H295R and in Dihydrotestosterone (DHT) in MUC1 (p<0.05), respectively. Outcome: This therapeutic effect was independent of the actions of ACTH, postulating a promising application of PPARG activation in endogenous hypercortisolism.
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Síndrome de Cushing , Humanos , Adrenalectomia/métodos , Síndrome de Cushing/genética , Síndrome de Cushing/cirurgia , Síndrome de Cushing/tratamento farmacológico , Hidrocortisona/metabolismo , Hiperplasia , PPAR gama/genéticaRESUMO
Representative, actively collected surveillance data on asymptomatic SARS-CoV-2 infections in primary schoolchildren remain scarce. We evaluated the feasibility of a saliva mass screening concept and assessed infectious activity in primary schools. During a 10-week period from 3 March to 21 May 2021, schoolchildren and staff from 17 primary schools in Munich participated in the sentinel surveillance, cohort study. Participants were tested using the Salivette® system, testing was supervised by trained school staff, and samples were processed via reverse transcription quantitative polymerase chain reaction (RT-qPCR). We included 4433 participants: 3752 children (median age, 8 [range, 6-13] years; 1926 girls [51%]) and 681 staff members (median age, 41 [range, 14-71] years; 592 women [87%]). In total, 23,905 samples were processed (4640 from staff), with participants representing 8.3% of all primary schoolchildren in Munich. Only eight cases were detected: Five out of 3752 participating children (0.13%) and three out of 681 staff members (0.44%). There were no secondary cases. In conclusion, supervised Salivette® self-sampling was feasible, reliable, and safe and thus constituted an ideal method for SARS-CoV-2 mass screenings in primary schoolchildren. Our findings suggest that infectious activity among asymptomatic primary schoolchildren and staff was low. Primary schools appear to continue to play a minor role in the spread of SARS-CoV-2 despite high community incidence rates.
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BACKGROUND: Drug-induced liver injury (DILI) is the most common reason for withdrawal of anticancer drugs from the market. To prevent adverse side effects of drugs, it is important to investigate potential toxicity in vitro. However, outcome of cytotoxicity screenings can differ remarkably depending on the method used. OBJECTIVE: We aimed to compare XTT, ATP-based CellTiter-Glo®2.0 and trypan blue exclusion (TBE) assays regarding their sensitivity in detecting acute cytotoxicity on HepG2 cells after incubation with the classical anticancer drugs Taxol and Imatinib or with the proteasome inhibitor MG-132. METHODS: HepG2 cells were treated for 48âh and cell viability was analysed by XTT, CellTiter-Glo®2.0 or TBE assay. RESULTS: All tested compounds showed a reduction of viability of HepG2 cells. However, assay results differed significantly: Both ATP-based and TBE assay showed concentration-dependent cytotoxic effects, but outcomes were less pronounced with TBE. In contrast, the widely used XTT assay did not detect any acute cytotoxicity of Taxol and Imatinib. CONCLUSIONS: Acute cytotoxic effects of tested compounds could be revealed. However, results were significantly different from each other with ATP assay being the most sensitive one under the conditions tested. Thus, acute cytotoxicity can be dramatically underestimated if only standard XTT test is used.