Negligible risk of surface transmission of SARS-CoV-2 in public transportation.

BACKGROUND: Exposure to pathogens in public transport systems is a common means of spreading infection, mainly by inhaling aerosol or droplets from infected individuals. Such particles also contaminate surfaces, creating a potential surface-transmission pathway. METHODS: A fast acoustic biosensor with an antifouling nano-coating was introduced to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on exposed surfaces in the Prague Public Transport System. Samples were measured directly without pre-treatment. Results with the sensor gave excellent agreement with parallel quantitative reverse-transcription polymerase chain reaction (qRT-PCR) measurements on 482 surface samples taken from actively used trams, buses, metro trains and platforms between 7 and 9 April 2021, in the middle of the lineage Alpha SARS-CoV-2 epidemic wave when 1 in 240 people were COVID-19 positive in Prague. RESULTS: Only ten of the 482 surface swabs produced positive results and none of them contained virus particles capable of replication, indicating that positive samples contained inactive virus particles and/or fragments. Measurements of the rate of decay of SARS-CoV-2 on frequently touched surface materials showed that the virus did not remain viable longer than 1-4 h. The rate of inactivation was the fastest on rubber handrails in metro escalators and the slowest on hard-plastic seats, window glasses and stainless-steel grab rails. As a result of this study, Prague Public Transport Systems revised their cleaning protocols and the lengths of parking times during the pandemic. CONCLUSIONS: Our findings suggest that surface transmission played no or negligible role in spreading SARS-CoV-2 in Prague. The results also demonstrate the potential of the new biosensor to serve as a complementary screening tool in epidemic monitoring and prognosis.

Functionalized Terpolymer-Brush-Based Biointerface with Improved Antifouling Properties for Ultra-Sensitive Direct Detection of Virus in Crude Clinical Samples.

New analytical techniques that overcome major drawbacks of current routinely used viral infection diagnosis methods, i.e., the long analysis time and laboriousness of real-time reverse-transcription polymerase chain reaction (qRT-PCR) and the insufficient sensitivity of "antigen tests", are urgently needed in the context of SARS-CoV-2 and other highly contagious viruses. Here, we report on an antifouling terpolymer-brush biointerface that enables the rapid and sensitive detection of SARS-CoV-2 in untreated clinical samples. The developed biointerface carries a tailored composition of zwitterionic and non-ionic moieties and allows for the significant improvement of antifouling capabilities when postmodified with biorecognition elements and exposed to complex media. When deployed on a surface of piezoelectric sensor and postmodified with human-cell-expressed antibodies specific to the nucleocapsid (N) protein of SARS-CoV-2, it made possible the quantitative analysis of untreated samples by a direct detection assay format without the need of additional amplification steps. Natively occurring N-protein-vRNA complexes, usually disrupted during the sample pre-treatment steps, were detected in the untreated clinical samples. This biosensor design improved the bioassay sensitivity to a clinically relevant limit of detection of 1.3 × 104 PFU/mL within a detection time of only 20 min. The high specificity toward N-protein-vRNA complexes was validated both by mass spectrometry and qRT-PCR. The performance characteristics were confirmed by qRT-PCR through a comparative study using a set of clinical nasopharyngeal swab samples. We further demonstrate the extraordinary fouling resistance of this biointerface through exposure to other commonly used crude biological samples (including blood plasma, oropharyngeal, stool, and nasopharyngeal swabs), measured via both the surface plasmon resonance and piezoelectric measurements, which highlights the potential to serve as a generic platform for a wide range of biosensing applications.

Is autoimmune pancreatitis a risk factor for pancreatic adenocarcinoma?

Immunoglobulin G4-related diseases (IgG4-RD) are a group of diseases characterized by high serum levels of immunoglobulin G4 (IgG4), increased lymphocyte and plasma cell with IgG4 positivity in the parenchyma of some organs, and storiform fibrosis. The most frequently affected organ is the pancreas. This is an autoimmune form of pancreatitis, which can be divided into two types: Type 1, which is significantly more common than Type 2, is high in IgG4 in the pancreatic parenchyma and shows a fundamental difference in the noted presence of extrapancreatic disorders. In general, chronic inflammation is a risk factor in the development of carcinomas. Chronic pancreatitis is an accepted risk factor for the development of pancreatic cancer. The question is whether this also applies to autoimmune pancreatitis (AIP), which has some mediators of inflammation in common with sporadic pancreatitis, and what role the presence of IgG4 plays. The vast majority of the work on this topic consists of case reports, yet, even based on our own experience, we would like to say that there is a relationship between the autoimmune form of pancreatitis and pancreatic cancer, which usually occurs in the first two years after diagnosis of AIP. Also significant is the fact that the group of people with AIP, who is a clinical manifestation of IgG4-RD, was found to have an even higher incidence of extrapancreatic cancer than in the pancreas itself. Differentiating AIP from pancreatic cancer can sometimes be problematic since these diseases can both present as focal pancreatic lesions. IgG4 has been considered useful for AIP diagnosis, however, IgG4 levels can be slightly elevated, as in the case with pancreatic adenocarcinoma. IgG4 levels of over twice the upper limit are rare among patients with pancreatic adenocarcinoma. However, cases of simultaneous presentation of pancreatic cancer and AIP have been documented and should not be neglected. AIP is a condition where regular followup is mandatory, including from the perspective of possible cancerogenesis.

The role of metabolic syndrome in the induction of chronic pancreatitis after a first attack of acute pancreatitis - multicenter trial.

BACKGROUND: Metabolic syndrome is a serious societal problem worldwide. In the Czech Republic more than 30% of the adult population are sufferers. The role of recurrent acute pancreatitis in the induction of chronic pancreatitis, following the socalled „mechanistic definition“ of chronic pancreatitis, has been unequivocally confirmed. However, there are a number of factors that may contribute to the development of chronic pancreatitis. The first aim of the study was to determine whether the metabolic syndrome may affect the development of chronic pancreatitis. The second question we asked ourselves was whether even one acute attack of pancreatitis could be an inductive factor in chronic pancreatitis. METHODS: Based on data obtained retrospectively from a total of 264 people diagnosed with chronic pancreatitis in 4 centers, a total of 59 people (22.3%) diagnosed within 36 months of a first attack of acute pancreatitis was obtained. Etiologies of either genetically induced pancreatitis or autoimmune pancreatitis were excluded. Diagnostics to identify the presence of metabolic syndrome were run on the 59 persons so obtained using the criteria from the socalled „harmonized“ definition of 2009 (obesity, arterial hypertension, hypertriglyceridemia, type 2 diabetes mellitus and a decreased level of HDL cholesterol). RESULTS: Comparing the findings of the individual components of metabolic syndrome in persons with chronic pancreatitis after a 1st attack of acute pancreatitis with the metabolic syndrome and in persons with chronic pancreatitis after the 1st attack of acute pancreatitis but without metabolic syndrome, a statistically significant difference in obesity was found (82.5% vs. 28.5%), hypertriglyceridemia (82.3% vs 17.8%) and arterial hypertension (70.5% vs 21.4%). The interval during which chronic pancreatitis occurred after acute pancreatitis averaged 12 months (10-14 months) in subjects with metabolic syndrome, whereas in the group without metabolic syndrome the interval was longer, 20 months (16-29 months). CONCLUSION: Our results show that even one attack of acute pancreatitis (regardless of etiology) can be an inductive factor in chronic pancreatitis. The presence of metabolic syndrome can accelerate the development of chronic pancreatitis after one has had acute pancreatitis.

Pancreatic Solid Focal Lesions: Differential Diagnosis between Autoimmune Pancreatitis and Pancreatic Cancer.

BACKGROUND: Diagnosis of pancreatic cancer (PC) in early stages is still challenging for gastroenterologists. The early detection of cancer is one of the utmost importance for the successful therapy of this malignancy. An accurate differential diagnosis of focal pancreatic lesions plays also an important role, whether it is differential diagnosis of chronic pancreatitis from PC or autoimmune pancreatitis (AIP) from PC. Raised serum immunoglobulin G4 (IgG4) levels to twice the normal value are considered one of significant diagnostic features of type 1 AIP. However, IgG4 can be increased also in patients with PC, but levels usually do not exceed twice the normal value. METHODS: In years 2012-2017, IgG4 serum levels were examined in 115 patients with histologically confirmed PC. Patients with PC and elevated IgG4 level (above 135 mg/dL) had tested their histological resection specimens or bioptic specimens from pancreatic lesion, with targeted detection of the presence of IgG4 and plasmocytes in the pancreatic tissue and changes characteristic for type 1 AIP. RESULTS: A plasmatic IgG4 level in 115 patients with diagnosed PC was higher than 135 mg/dL in 14 patients (12.2%). Out of them, 2 patients (1.7%) revealed a serum IgG4 level higher than double the normal value, that is, higher than 270.0 mg/dL (suggestive of AIP). One patient met histological criteria for diagnosis of AIP in the simultaneous presence of PC. CONCLUSION: Diagnosis of early cancer stages, particularly differentiating AIP from PC can be sometimes problematic. IgG4 levels can be slightly elevated also in case of PC. A targeted biopsy of the pancreas is the method of choice in cases suspected from a focal form of AIP and we recommend to prefer it over other modalities, such as, for example, response to steroid therapy.