Diagnostic yield of serial SARS-CoV-2 testing in hospitalized patients.

BACKGROUND: The detection rate of SARS-CoV-2 by polymerase chain reaction (PCR) varies depending on the time since exposure and is highest around the time of symptom onset. It is conceivable that patients who are incubating SARS-CoV-2 may screen negative at admission and develop transmissible but undetected asymptomatic or pre-symptomatic disease while in hospital. The incidence of COVID-19 in Montreal, Canada started to increase in December 2020. In anticipation of a much larger rise after the holiday period, the McGill University Health Centre implemented serial SARS-CoV-2 testing for all admitted patients on day 5 and 10 after admission, to evaluate the clinical utility of serial SARS-CoV-2 testing among patients who test negative on admission screening. METHODS: We retrospectively analyzed the diagnostic yield of SARS-CoV-2 serial testing for patients admitted between January 4, 2021 and April 30, 2021. RESULTS: A total of 1,505 patients underwent serial testing at day 5 and 841 patients underwent serial testing at day 10. Only 10 patients were positive on serial testing at day 5 and only 12 patients were positive on serial testing at day 10, for a yield at day 5 and day 10 of 0.7% and 1.4%, respectively. CONCLUSIONS: The yield of serial SARS-CoV-2 testing was 0.7% at day 5 and 1.4% at day 10. We found that the yield of serial testing was higher when the community incidence was higher and could be considered in this situation. Policies which target repeat testing towards symptomatic or exposed individuals appear to be effective in identifying those with a positive test while admitted but testing negative upon admission.

HISTORIQUE: Le taux de détection du SRAS-CoV-2 par l'amplification en chaîne par polymérase (PCR) varie en fonction de la période écoulée depuis l'exposition et est plus élevé aux alentours du moment d'apparition des symptômes. Il se peut que les patients en période d'incubation du SRAS-CoV-2 obtiennent un résultat négatif à leur admission, puis développent une maladie asymptomatique ou présymptomatique non détectée pendant leur séjour hospitalier. L'incidence de COVID-19 a commencé à augmenter à Montréal, au Canada, en décembre 2020. En prévision d'une hausse beaucoup plus marquée après la période des fêtes, le Centre universitaire de santé McGill a mis en œuvre des tests sériels du SRAS-CoV-2 pour tous les patients hospitalisés le cinquième et le dixième jour après leur hospitalisation, afin d'évaluer l'utilité clinique des tests sériels du SRAS-CoV-2 chez les patients qui avaient reçu un résultat négatif lors du dépistage à leur admission. MÉTHODOLOGIE: Les chercheurs ont procédé à une analyse rétrospective du taux diagnostique des tests sériels du SRAS-CoV-2 chez les patients hospitalisés entre le 4 janvier et le 30 avril 2021. RÉSULTATS: Au total, 1 505 patients se sont soumis au test sériel le cinquième jour et 841 patients, le dixième jour. Seulement dix patients ont obtenu un résultat positif au test sériel le cinquième jour (0,7 %) et seulement 12, le dixième jour (1,4 %). CONCLUSIONS: Le taux de résultats positifs aux tests sériels du SRAS-CoV-2 s'élevait à 0,7 % le cinquième jour et à 1,4 % le dixième jour. Il était plus marqué lorsque l'incidence communautaire était plus élevée; les tests sériels pourraient être envisagés dans cette situation. Les politiques qui ciblent les tests répétés chez les personnes symptomatiques ou exposées semblent efficaces pour détecter celles dont le résultat est positif pendant leur hospitalisation, mais qui ont obtenu un résultat négatif à leur admission.

Finding distinctions between oral cancer and periodontitis using saliva metabolites and machine learning.

OBJECTIVE: The aim of this research is the study of metabolic pathways related to oral cancer and periodontitis along with development of machine-learning model for elucidation of these diseases based on saliva metabolites of patients. METHODS: Data mining, metabolomic pathways analysis, study of metabolite-gene networks related to these diseases. Machine-learning and deep-learning methods for development of the model for recognition of oral cancer versus periodontitis, using patients' saliva. RESULTS: The most accurate classifications between oral cancer and periodontitis were performed using neural networks, logistic regression and stochastic gradient descent confirmed by the separate 10-fold cross-validations. The best results were achieved by the deep-learning neural network with the TensorFlow program. Accuracy of the resulting model was 79.54%. The other methods, which did not rely on deep learning, were able to achieve comparable, although slightly worse results with respect to accuracy. CONCLUSION: Our results demonstrate a possibility to distinguish oral cancer from periodontal disease by analysis the saliva metabolites of a patient, using machine-learning methods. These findings may be useful in the development of a non-invasive method to aid care providers in determining between oral cancer and periodontitis quickly and effectively.

Relationship between dietary patterns and COPD: a systematic review and meta-analysis.

BACKGROUND: Findings from previous studies reporting on the associations between chronic obstructive pulmonary disease (COPD) and various dietary patterns have been inconsistent. This review aims to summarise the evidence on the strength of the association between dietary patterns and the prevalence and incidence of COPD. METHODS: We conducted a comprehensive search of seven databases between 1 January 1980 and 30 November 2019. Two reviewers independently reviewed each manuscript through the screening, selection, data extraction and quality assessment stages. Data from eight observational studies that met the inclusion criteria were extracted and random-effects meta-analysis was subsequently conducted. RESULTS: Eight observational studies (all eight reporting on healthy dietary patterns and three on unhealthy dietary patterns) met the inclusion criteria and data were extracted to include in the meta-analysis. Consumption of a healthy dietary pattern was associated with a lower risk of COPD (pooled OR 0.88, 95% CI 0.82-0.94). Consumption of unhealthy dietary patterns was associated with a higher risk of COPD (OR 1.22, 95% CI 0.84-1.76); however, the results were not statistically significant and had high heterogeneity (I2=91%). CONCLUSION: Our results suggests that healthy dietary patterns are associated with a lower prevalence of COPD, while unhealthy dietary patterns are not. More studies, particularly adequately powered longitudinal studies, are needed to further elucidate the effects of healthy and unhealthy dietary patterns on risk of COPD.

Validation of concurrent preimplantation genetic testing for polygenic and monogenic disorders, structural rearrangements, and whole and segmental chromosome aneuploidy with a single universal platform.

Preimplantation genetic testing (PGT) has been successfully applied to reduce the risk of miscarriage, improve IVF success rates, and prevent inheritance of monogenic disease and unbalanced translocations. The present study provides the first method capable of simultaneous testing of aneuploidy (PGT-A), structural rearrangements (PGT-SR), and monogenic (PGT-M) disorders using a single platform. Using positive controls to establish performance characteristics, accuracies of 97 to >99% for each type of testing were observed. In addition, this study expands PGT to include predicting the risk of polygenic disorders (PGT-P) for the first time. Performance was established for two common diseases, hypothyroidism and type 1 diabetes, based upon availability of positive control samples from commercially available repositories. Data from the UK Biobank, eMERGE, and T1DBASE were used to establish and validate SNP-based predictors of each disease (7,311 SNPs for hypothyroidism and 82 for type 1 diabetes). Area under the curve of disease status prediction from genotypes alone were 0.71 for hypothyroidism and 0.68 for type 1 diabetes. The availability of expanded PGT to evaluate the risk of polygenic disorders in the preimplantation embryo has the potential to lower the prevalence of common genetic disease in humans.

18F-DCFPyL PET/CT in Oncocytoma.

A 76-year-old man with biochemical failure after primary radiotherapy for prostate cancer had no malignant disease detected on Tc-MDP bone scan and diagnostic CT. Prostate-specific membrane antigen (PSMA), a type II transmembrane glycoprotein, is overexpressed in prostate cancer cells. The PSMA-targeted F-DCFPyL PET/CT demonstrated lymph node disease and photopenic defects in the left kidney associated with a cyst and biopsy-proven oncocytoma. Prostate-specific membrane antigen is expressed in the neovasculature of several solid tumors. It has been reported that PSMA expression is seen in approximately 50% of oncocytoma versus 76% of clear cell renal carcinomas. Biopsy confirmation is needed regardless of F-DCFPyL avidity.

Addictive Eating and Its Relation to Physical Activity and Sleep Behavior.

The obesity epidemic has led to the exploration of factors contributing to its etiology. Addictive eating, physical activity, and sleep behaviors have all been independently associated with obesity, and recent research suggests plausible interrelationships between food addiction, physical activity, and sleep. This study aims to investigate the relationship between food addiction with physical activity and sleep behavior. Australian adults were invited to complete an online survey which collected information including: demographics, food addiction symptoms, physical activity, sitting time and sleep behavior items. The sample comprised 1344 individuals with a mean age of 39.8 ± 13.1 years (range 18⁻91), of which 75.7% were female. Twenty-two percent of the sample met the criteria for a diagnosis of food addiction as per the Yale Food Addiction Scale (YFAS 2.0) criteria, consisting of 0.7% with a "mild" addiction, 2.6% "moderate", and 18.9% classified as having a "severe" food addiction. Food-addicted individuals had significantly less physical activity (1.8 less occasions walking/week, 32 min less walking/week, 58 min less moderate to vigorous physical activity (MVPA)/week; p < 0.05), reported sitting for longer on weekends (83 min more on weekends/week; p < 0.001), and reported significantly more symptoms of poorer-quality sleep (more likely to snore, more likely to have fallen asleep while driving, reported more days of daytime falling asleep; p < 0.05) compared to non-food-addicted individuals. These differences were also observed in those with a "severe" food addiction classification. The present study suggests frequency and duration of physical activity, time spent sitting and sleep duration are associated with food addiction.

Computational modeling and design of a new open clip surgical instrument.

This research introduces a new surgical clip instrument with improved mechanism to apply the metal clips to patient's vessel/tissues in the surgical operations. The improved clip delivery system has been designed and developed in the instrument to improve the clip distal move from clip channel into jaw guide track and resolve the problems of clip accidental shooting out when clip is being loaded into jaw pair by compression spring that has been normally used in some current surgical clip instruments. With this improvement, this new surgical open clip instrument can prevent patient's vessels and tissues from being damaging because the distal move of clips is well controlled without clip drop-off incident. Plus the operational force to form the clip is lower than regular surgical instruments due to new mechanism design. In addition to the above, the manufacturing and product cost can be decreased because the dimensional tolerance of components, such as clip channel and jaw guide track, can be wider due to this new instrument design. The prototype of this new instrument is analyzed and optimized through computer aided modeling and simulation, in order to prove its feasible function, reliable performance, and mechanical advantage. All these improved features have also been tested and verified through the prototype. With some further improvement to this new instrument design and valuable evaluations from surgeon and clinical fields in next several months, the commercial availability of this surgical clip instrument will be anticipate in 1-2 years.