Theranos revisited: the trial and lessons learned

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Pancreatic cancer-derived S-100A8 N-terminal peptide: a diabetes cause?

BACKGROUND: Our aim was to identify the pancreatic cancer diabetogenic peptide. METHODS: Pancreatic tumor samples from patients with (n=15) or without (n=7) diabetes were compared with 6 non-neoplastic pancreas samples using SDS-PAGE. RESULTS: A band measuring approximately 1500 Da was detected in tumors from diabetics, but not in neoplastic samples from non-diabetics or samples from non-neoplastic subjects. Sequence analysis revealed a 14 amino acid peptide (1589.88 Da), corresponding to the N-terminal of the S100A8. At 50 nmol/L and 2 mmol/L, this peptide significantly reduced glucose consumption and lactate production by cultured C(2)C(12) myoblasts. The 14 amino acid peptide caused a lack of myotubular differentiation, the presence of polynucleated cells and caspase-3 activation. CONCLUSIONS: The 14 amino acid peptide from S100A8 impairs the catabolism of glucose by myoblasts in vitro and may cause hyperglycemia in vivo. Its identification in biological fluids might be helpful in diagnosing pancreatic cancer in patients with recent onset diabetes mellitus

Pancreatic cancer-associated diabetes mellitus: an open field for proteomic applications.

Background: Diabetes mellitus is associated with pancreatic cancer in more than 80% of the cases. Clinical, epidemiological, and experimental data indicate that pancreatic cancer causes diabetes mellitus by releasing soluble mediators which interfere with both beta-cell function and liver and muscle glucose metabolism. Methods: We analysed, by matrix-assisted laser desorption ionization time of flight (MALDI-TOF), a series of pancreatic cancer cell lines conditioned media, pancreatic cancer patients' peripheral and portal sera, comparing them with controls and chronic pancreatitis patients' sera. Results: MALDI-TOF analysis of pancreatic cancer cells conditioned media and patients' sera indicated a low molecular weight peptide to be the putative pancreatic cancer-associated diabetogenic factor. The sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis of tumor samples from diabetic and non-diabetic patients revealed the presence of a 1500 Da peptide only in diabetic patients. The amino acid sequence of this peptide corresponded to the N-terminal of an S-100 calcium binding protein, which was therefore suggested to be the pancreatic cancer-associated diabetogenic factor. Conclusions: We identified a tumor-derived peptide of 14 amino acids sharing a 100% homology with an S-100 calcium binding protein, which is probably the pancreatic cancer-associated diabetogenic facto

Comparison of three different immunoassays in the diagnosis of heparin-induced thrombocytopenia.

Background: Heparin-induced thrombocytopenia (HIT) is caused by platelet activating antibodies that recognize platelet factor 4/heparin (PF4/H) complexes. Laboratory testing plays a key role in the diagnosis of HIT. As functional assays are unfeasible for most clinical laboratories, antigen binding assays are commonly used in routine testing. However, their low specificity leads to overdiagnosis of HIT. Therefore, it is advisable to improve screening tests in this setting. Methods: Blood samples from 114 patients in whom HIT was suspected were investigated using a chemiluminescence test (HemosIL (R) AcuStar HIT-IgG), a PF4/H IgG enzyme immunoassay (Lifecodes PF4 IgG), an IgG-specific lateral flow immunoassay heparin-induced thrombocytopenia (LFI-HIT, STic Expert (R) HIT) and the heparin-induced platelet aggregation (HIPA) test. Results: Twenty-nine (25.4%) out of 114 subjects with suspected HIT had a positive HIPA test. None of patients with a 4Ts score <4 were positive at HIPA. HemosIL (R) AcuStar HIT-IgG showed the best performance in term of sensitivity and specificity when used as single test. Receiver operating characteristic (ROC) analysis showed optimization of sensitivity and specificity using a cut-off of 1.13 U/mL (0.95 and 0.98, respectively). As an alternative approach, a strategy based on screening samples by STic Expert (R) HIT and then retesting positive results by Lifecodes PF4 IgG (cut-off 1 OD) or HemosIL (R) AcuStar HIT-IgG (cut-off 1.3 U/mL) showed a performance compared to a single test approach by HemosIL (R) AcuStar HIT-IgG. Conclusions: The HemosIL (R) AcuStar HIT or a combinatorial approach with the STic Expert (R) HIT and the PF4/H IgG enzyme immunoassay provide an accurate diagnosis of immune HIT

Neonates with SARS-CoV-2 infection: spectrum of disease from a prospective nationwide observational cohort study.

Coronavirus disease 2019 (COVID-19) can be more severe in infants than in older children. To date, only a few case series have reported data on neonates with COVID-19, including mostly asymptomatic neonates who were tested because of exposure to maternal SARS-CoV-2 infection. This study summarises nationwide epidemiological data, clinical characteristics, treatment and outcomes of neonates presenting with symptomatic SARS-CoV-2 infection. Data were prospectively collected through the Swiss Paediatric Surveillance Unit from hospitalised neonates with laboratory-confirmed SARS-CoV-2 infection (positive polymerase chain reaction on a respiratory sample) from 1 March 2020 to 31 September 2021. All 29 paediatric hospitals in Switzerland reported cases. In total, 73 neonates were included; 7 (10%) were preterm. The median age at presentation was 17 days (interquartile range [IQR] 11-23); 40 (55%) were female. The majority of neonates (64, 88%) were admitted from home. Nine (12%) had a pre-existing medical condition. Overall, the most common symptom recorded was fever in 52 (71%), followed by rhinorrhoea or nasal congestion in 32 (44%) and respiratory distress in 19 (26%). Twenty (27%) neonates presented with fever without a source. Seven (10%) neonates were admitted to an intensive care unit (5 for respiratory failure and 2 for monitoring). One (1%) neonate required inotropic support. The median length of hospital stay in term neonates was 4 days (IQR 3-5). Two (3%) were treated with corticosteroids and 1 (1%) with remdesivir. In total, 60 (82%) neonates had contact with a known or suspected SARS-CoV-2 index case. All of the 71 neonates for whom data were available were discharged to their homes without symptoms. In neonates, COVID-19 mainly presents with fever, and symptoms of upper and lower respiratory tract infection. The clinical course is mostly mild, requiring a short period of hospitalisation. COVID-19 needs to be added as a differential diagnosis in neonates who present with fever without a source. However, the presence of SARS-CoV-2 should not deter from the search for a serious bacterial infection. Further data from surveillance studies are needed to better understand COVID-19 in neonates, guide therapy and to evaluate whether the clinical spectrum is changing with new SARS-CoV-2 variants

Non-specific oral and cutaneous manifestations of coronavirus disease 2019 in children

Background: Coronavirus Disease 2019 (COVID-19) seems to affect children only marginally, as a result, there is less knowledge of its manifestations in childhood. The purpose of this retrospective cross-sectional study was to investigate the oral and cutaneous manifestations in children affected by COVID-19. Material and Methods: All the medical records of children with COVID-19 admitted to the Pediatric Clinic-ASST Spedali Civili of Brescia from March to April 2020 were reviewed. The following data were recorded: Age, temperature, clinical presentation, oral mucosa lesions, taste alteration and cutaneous lesions. Results: The medical records of twenty-seven pediatric patients (mean age 4,2 years + 1,7) were analyzed. The clinical presentation of the disease mainly included elevated body temperature and cough. The following oral lesions were recorded: Oral pseudomembranous candidiasis (7.4 %), geographic tongue (3.7%), coated tongue (7.4 %) and hyperaemic pharynx (37 %). Taste alteration was reported by 3 patients. Six patients presented cutaneous flat papular lesions. Conclusions: As for our paediatric sample, COVID-19 resulted to be associated with non-specific oral and cutaneous manifestations

Beta-agonist stimulation ameliorates the phenotype of spinal and bulbar muscular atrophy mice and patient-derived myotubes

Spinal and bulbar muscular atrophy (SBMA) is a neuromuscular disease characterized by the loss of lower motor neurons. SBMA is caused by expansions of a polyglutamine tract in the gene coding for androgen receptor (AR). Expression of polyglutamine-expanded AR causes damage to motor neurons and skeletal muscle cells. Here we investigated the effect of β-agonist stimulation in SBMA myotube cells derived from mice and patients, and in knock-in mice. We show that treatment of myotubes expressing polyglutamine-expanded AR with the β-agonist clenbuterol increases their size. Clenbuterol activated the phosphatidylinositol-3-kinase (PI3K)/Akt/mechanistic target of rapamycin (mTOR) pathway and decreased the accumulation of polyglutamine-expanded AR. Treatment of SBMA knock-in mice with clenbuterol, which was started at disease onset, ameliorated motor function and extended survival. Clenbuterol improved muscle pathology, attenuated the glycolytic-to-oxidative metabolic alterations occurring in SBMA muscles and induced hypertrophy of both glycolytic and oxidative fibers. These results indicate that β-agonist stimulation is a novel therapeutic strategy for SBMA

Pepsinogen A, pepsinogen C, and gastrin as markers of atrophic chronic gastritis in European dyspeptics

Serum levels of pepsinogen and gastrin are parameters that can be used as biomarkers for gastric mucosa. The aim of this study was to validate these serum biomarkers, that is pepsinogen A (PGA), pepsinogen C (PGC), PGA/PGC ratio, and gastrin, as screening tests for precancerous lesions: atrophic chronic gastritis (ACG) or Helicobacter pylori-related corpus-predominant or multifocal atrophy. The study population was comprised of a subsample of 284 patients from the 451 included in the Eurohepygast cohort, between 1995 and 1997. The concentrations of PGA, PGC, and gastrin were measured by radioimmunoassays. Histological diagnosis was the gold standard. Cut-off points were calculated using receiving operator characteristics (ROC) curves. Factors linked to variation of biomarkers were identified using multivariate linear regression. The mean of each biomarker in the sample was: PGA, 77.4 μg l−1; PGC, 13.2 μg l−1; PGA/PGC, 6.7; and gastrin, 62.4 ng l−1. For ACG patients, the areas under the PGA, PGC, PGA/PGC, and gastrin ROC curves were 0.55, 0.62, 0.73, and 0.58, respectively. The best cut-off point for PGA/PGC was 5.6, with sensitivity 65% and specificity 77.9%. For H. pylori-related corpus-predominant or multifocal atrophy, the areas under the respective ROC curves were 0.57, 0.67, 0.84, and 0.69. The best cut-off point for PGA/PGC was 4.7, with sensitivity 77.1% and specificity 87.4%. The results suggested that only the PGA/PGC ratio can be considered as a biomarker for precancerous lesions of the stomach, and may be useful as a screening test

Plasma and dried blood spot lysosphingolipids for the diagnosis of different sphingolipidoses: a comparative study.

Abstract Background Lysosphingolipids, the N-deacylated forms of sphingolipids, have been identified as potential biomarkers of several sphingolipidoses, such as Gaucher, Fabry, Krabbe and Niemann-Pick diseases and in GM1 and GM2 gangliosidoses. To date, different methods have been developed to measure various lysosphingolipids (LysoSLs) in plasma. Here, we present a novel liquid chromatography tandem mass spectrometry (LC-MS/MS) assay for a simultaneous quantification of LysoSLs (HexSph, LysoGb3, LysoGM1, LysoGM2, LysoSM and LysoSM509) in dried blood spot (DBS). This LC-MS/MS method was used to compare the levels of LysoSLs in DBS and plasma in both affected patients and healthy controls. Methods Lysosphingolipids were extracted from a 3.2 mm diameter DBS with a mixture of methanol:acetonitrile:water (80:15:5, v/v) containing internal stable isotope standards. Chromatographic separation was performed using a C18 column with a gradient of water and acetonitrile both with 0.1% formic acid in a total run time of 4 min. The compounds were detected in the positive ion mode electrospray ionization (ESI)-MS/MS by multiple reaction monitoring (MRM). Results The method was validated on DBS to demonstrate specificity, linearity, lowest limit of quantification, accuracy and precision. The reference ranges were determined in pediatric and adult populations. The elevated levels of LysoSLs were identified in Gaucher disease (HexSph), Fabry disease (LysoGb3), prosaposin deficiency (HexSph and LysoGb3) and Niemann-Pick disease types A/B and C (LysoSM and LysoSM509). The correlation in the levels between DBS and plasma was excellent for LysoGb3 and HexSph but poor for LysoSM and LysoSM509. Conclusions Despite the fact that plasma LysoSLs determination remains the gold standard, our LC-MS/MS method allows a rapid and reliable quantification of lysosphingolipids in DBS. The method is a useful tool for the diagnosis of different sphingolipidoses except for Niemann-Pick type C

Inherited human gp91phox deficiency is associated with impaired isoprostane formation and platelet dysfunction

Platelet isoprostane 8-ISO-prostaglandin F2α (8-iso-PGF2α), a proaggregating molecule, is believed to derive from nonenzymatic oxidation of arachidonic acid. We hypothesized that NADPH is implicated in isoprostane formation and platelet activation