The development of new methods for direct viral detection using streamlined and ideally reagent-free assays is a timely and important, but challenging, problem. The challenge of combatting the ...COVID-19 pandemic has been exacerbated by the lack of rapid and effective methods to identify viral pathogens like SARS-CoV-2 on-demand. Existing gold standard nucleic acid-based approaches require enzymatic amplification to achieve clinically relevant levels of sensitivity and are not typically used outside of a laboratory setting. Here, we report reagent-free viral sensing that directly reads out the presence of viral particles in 5 minutes using only a sensor-modified electrode chip. The approach relies on a class of electrode-tethered sensors bearing an analyte-binding antibody displayed on a negatively charged DNA linker that also features a tethered redox probe. When a positive potential is applied, the sensor is transported to the electrode surface. Using chronoamperometry, the presence of viral particles and proteins can be detected as these species increase the hydrodynamic drag on the sensor. This report is the first virus-detecting assay that uses the kinetic response of a probe/virus complex to analyze the complexation state of the antibody. We demonstrate the performance of this sensing approach as a means to detect, within 5 min, the presence of the SARS-CoV-2 virus and its associated spike protein in test samples and in unprocessed patient saliva.
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IJS, KILJ, NUK, PNG, UL, UM
Introduction
Endoscopic resection (ER) of early gastric cancer (EGC) is increasingly used in Eastern countries due to their low rates of lymph node metastasis (LNM); however, there is a paucity of ...evidence in Western countries. We investigated LNM and its effect on overall survival (OS) in Western patients with EGC.
Methods
Patients diagnosed with T1 gastric cancer between 2000 and 2017 were retrospectively evaluated. Univariate Kaplan–Meier, multivariate logistic and Cox‐regression models were used to assess the associations between clinical characteristics, LNM, and OS.
Results
Among 86 patients, median age was 68 years and 72% were male. Node positivity was 30%. Two percent of patients met the classical guidelines for ER and all were node‐negative, while 16% met expanded criteria of which 14% were node‐positive. T1b disease (odds ratio OR 41.2 95% confidence interval CI 1.62–1048, p = 0.02) and lymphovascular/perineural invasion (OR 18.0 95% CI 2.41–134, p = 0.01) were predictive of node positivity. The 5‐year OS for node‐negative and node‐positive patients was 84% and 53% (p = 0.004), respectively.
Conclusions
The risk of LNM in Western patients with EGC is higher; therefore, generalizability of the expanded criteria for ER should be interpreted with caution.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Background
Surveillance guidelines following the resection of small bowel neuroendocrine tumors (SB‐NETs) are inconsistent. We evaluated the impact of surveillance imaging on SB‐NET recurrence and ...overall survival (OS).
Methods
Patients with completely resected SB‐NETs referred to a provincial cancer center (2004–2015) were reviewed. Associations between imaging frequency, recurrence, post‐recurrence treatment, and OS were determined using univariate and Cox‐regression analyses.
Results
Among 195 completely resected SB‐NET patients, 31% were ≥70 years, 43% were female, and 80% had grade 1 disease. Imaging frequency was predictive of recurrence (hazard ratio 2.52, 95% confidence interval 1.84–3.46, p < 0.001). 72% underwent interventions for recurrent disease. Patients who were treated for the recurrent disease had comparable OS to those who did not recur (median 152 vs. 164 months; p = 0.25). Imaging frequency was not associated with OS in those with treated recurrent disease (p = 0.65). Patients who recurred underwent more computerized tomography (CT) scans than those who did not recur (CT: 1.47 ± 0.89 vs. 1.02 ± 0.81 scans/year, p < 0.001). Detection of disease recurrence was 5%–7% per year during the first 6 years of surveillance and peaked at 17% in Year 9.
Conclusion
Less frequent imaging over a longer duration should be emphasized to capture clinically relevant recurrences that can be treated to improve OS.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The ability to rapidly diagnose, track, and disseminate information for SARS-CoV-2 is critical to minimize its spread. Here, we engineered a portable smartphone-based quantum barcode serological ...assay device for real-time surveillance of patients infected with SARS-CoV-2. Our device achieved a clinical sensitivity of 90% and specificity of 100% for SARS-CoV-2, as compared to 34% and 100%, respectively, for lateral flow assays in a head-to-head comparison. The lateral flow assay misdiagnosed ∼2 out of 3 SARS-CoV-2 positive patients. Our quantum dot barcode device has ∼3 times greater clinical sensitivity because it is ∼140 times more analytically sensitive than lateral flow assays. Our device can diagnose SARS-CoV-2 at different sampling dates and infectious severity. We developed a databasing app to provide instantaneous results to inform patients, physicians, and public health agencies. This assay and device enable real-time surveillance of SARS-CoV-2 seroprevalence and potential immunity.
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IJS, KILJ, NUK, PNG, UL, UM
A significant proportion of hospitalized patients are dependent on medical air. Medical air is commonly produced on-site from filtered and compressed external air before delivery to patients through ...centralized piping. Little is known about how outside ambient air composition can affect medical air quality. This study examined how chemical and microbial content of medical air varied at the delivery ports as a function of ambient air. The chemical composition was monitored near the outdoor air intake and at the indoor outlet in a patient room of a healthcare center. The microbial content was determined twice weekly using a custom-made impaction device designed for pressurized systems. Results revealed some chemical gases are not well filtered by the medical air system; the average concentrations of CO and CO2 in this medical air (160 ppb and 442 ppm) were similar to outdoor concentrations, indicating that these gases pass freely to bedside outlets. NOx and O3 are only 40% removed yielding average concentrations of 16 and 10 ppb in this medical air. Trace metals could also be detected. Bacteria were detected, but at concentrations significantly lower than 1 colony forming unit (CFU) per m3 of medical air sampled; these consisted predominantly of non-pathogenic bacteria. This study highlights the impact of changes in outdoor air quality on the composition of medical air delivered to patients, and the importance of monitoring and regulating the quality of medical air.
•Chemical and biological contamination in hospital medical air was measured.•The medical air quality reflected that of the outdoor air used to generate it.•CO and CO2 tracked outdoor air concentrations while O3 and NOx were partially removed.•Concentrations of particulate were much lower than in outside ambient air.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Around 32% of no-touch surfaces were positive for SARS-CoV-2 in long-term carefacilities.•Undetectable airborne SARS-CoV-2, 8-30 days after residents’ symptoms onset.•Reconsideration of exposure ...risks in LTCFs is necessary.•Timing is crucial in air sampling campaign deployment.•Collaboration of LTCFs is key to study and have quick access to COVID-19 outbreaks.
Long-term care facilities (LTCF) are environments particularly favorable to coronavirus disease (SARS-CoV-2) pandemic outbreaks, due to the at-risk population they welcome and the close proximity of residents. Yet, the transmission dynamics of the disease in these establishments remain unclear.
Air and no-touch surfaces of 31 rooms from 7 LTCFs were sampled and SARS-CoV-2 was quantified by real-time reverse transcription polymerase chain reaction (RT-qPCR).
Air samples were negative but viral genomes were recovered from 20 of 62 surface samples at concentrations ranging from 13 to 36,612 genomes/surface. Virus isolation (culture) from surface samples (n = 7) was negative.
The presence of viral RNA on no-touch surfaces is evidence of viral dissemination through air, but the lack of airborne viral particles in air samples suggests that they were not aerosolized in a significant manner during air sampling sessions. The air samples were collected 8 to 30 days after the residents’ symptom onset, which could indicate that viruses are aerosolized early in the infection process. Additional research is needed to evaluate viral viability conservation and the potential role of direct contact and aerosols in SARS-CoV-2 transmission in these institutions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Patterns of recurrence help to inform surveillance of patients with resected gastroenteropancreatic neuroendocrine tumors (GEP-NETs).
Patients with GEP-NETs in British Columbia, Canada (2004–2015) ...were reviewed. Associations between tumor characteristics, recurrence and survival were analyzed.
Among 759 patients, 41%, 25%, and 17% had grade 1, 2, and 3 disease, respectively. 387 patients had R0/R1 resections, of which 30% recurred (median 25 months). 5-year incidence of recurrence was 22% (grade 1), 46% (grade 2), and 59% (grade 3) (p < 0.001). Grade predicted distant recurrence (Grade 2 HR 1.89, 95% CI 1.16–3.07; p = 0.011; Grade 3 HR 3.29, 95% CI 1.81–5.99; p < 0.001). Compared to small bowel NETs, pancreas NETs had less peritoneal recurrence (OR 0.15, 95% CI 0.03–0.68, p = 0.014). No patients had isolated pulmonary recurrences.
Higher grade tumors and pancreatic NETs require more frequent surveillance. Evidence is limited for pulmonary surveillance.
•Among patients with resected GEP-NETs, tumor grade and primary location predicts timing and site of disease recurrence.•Peritoneal recurrences were most commonly associated with small bowel primaries.•Among 116 patients with recurrence, not a single GEP-NET had a first site of recurrence as the lung.•Surveillance imaging frequency and type should be based on characteristics of resected tumors to optimize patient outcomes.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Wildlife reservoirs of broad-host-range viruses have the potential to enable evolution of viral variants that can emerge to infect humans. In North America, there is phylogenomic evidence of ...continual transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from humans to white-tailed deer (Odocoileus virginianus) through unknown means, but no evidence of transmission from deer to humans. We carried out an observational surveillance study in Ontario, Canada during November and December 2021 (n = 300 deer) and identified a highly divergent lineage of SARS-CoV-2 in white-tailed deer (B.1.641). This lineage is one of the most divergent SARS-CoV-2 lineages identified so far, with 76 mutations (including 37 previously associated with non-human mammalian hosts). From a set of five complete and two partial deer-derived viral genomes we applied phylogenomic, recombination, selection and mutation spectrum analyses, which provided evidence for evolution and transmission in deer and a shared ancestry with mink-derived virus. Our analysis also revealed an epidemiologically linked human infection. Taken together, our findings provide evidence for sustained evolution of SARS-CoV-2 in white-tailed deer and of deer-to-human transmission.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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