THE HEMOCYTOLOGICAL CONSTITUTION OF ADULT MALE RABBITS FROM FIFTEEN STANDARD BREEDS

A study of the red blood cells, hemoglobin, blood platelets, and the total and individual white blood cells was made on 180 male rabbits of known age and representing fifteen standard breeds. An attempt was made to eliminate or bold constant such variables as age, sex, season, time of examination, technical errors, food, housing, and disease. The mean, variance of the mean, and standard deviation were calculated for each breed sample and for the group as a whole. An analysis of the variance showed that the variation between the breed samples was significantly greater than the variation within the breed samples for the red blood cells, hemoglobin, blood platelets, total white blood cells, basophiles, eosinophiles, and lymphocytes per cubic millimeter and in per cent and the neutrophiles in per cent. No significant variations were detected in the monocytes except when the breeds were divided into heavy and light breeds. No variation in the neutrophiles per cubic millimeter was detected; a large number of the breeds had exactly the same mean neutrophile level. Characteristic blood formulae were found for the various breed samples having an adequate numerical representation. It was concluded that the varying blood formulae could not be explained on any other, except an hereditary (genetic) basis.     

Towards clinical data-driven eligibility criteria optimization for interventional COVID-19 clinical trials

ObjectiveThis research aims to evaluate the impact of eligibility criteria on recruitment and observable clinical outcomes of COVID-19 clinical trials using electronic health record (EHR) data.Materials and MethodsOn June 18, 2020, we identified frequently used eligibility criteria from all the interventional COVID-19 trials in ClinicalTrials.gov (n = 288), including age, pregnancy, oxygen saturation, alanine/aspartate aminotransferase, platelets, and estimated glomerular filtration rate. We applied the frequently used criteria to the EHR data of COVID-19 patients in Columbia University Irving Medical Center (CUIMC) (March 2020–June 2020) and evaluated their impact on patient accrual and the occurrence of a composite endpoint of mechanical ventilation, tracheostomy, and in-hospital death.ResultsThere were 3251 patients diagnosed with COVID-19 from the CUIMC EHR included in the analysis. The median follow-up period was 10 days (interquartile range 4–28 days). The composite events occurred in 18.1% (n = 587) of the COVID-19 cohort during the follow-up. In a hypothetical trial with common eligibility criteria, 33.6% (690/2051) were eligible among patients with evaluable data and 22.2% (153/690) had the composite event.DiscussionBy adjusting the thresholds of common eligibility criteria based on the characteristics of COVID-19 patients, we could observe more composite events from fewer patients.ConclusionsThis research demonstrated the potential of using the EHR data of COVID-19 patients to inform the selection of eligibility criteria and their thresholds, supporting data-driven optimization of participant selection towards improved statistical power of COVID-19 trials.     

Exposure of Adult Mice to Environmental Tobacco Smoke Fails to Enhance the Immune Response to Inhaled Antigen

Epidemiologic evidence supports a role for environmental tobacco smoke (ETS) in the occurrence and severity of allergies/asthma. However, neither the precise combination of ETS and allergen exposure nor the mechanism (or mechanisms) by which these factors interact and contribute to asthma induction is known. Animal model studies have failed to establish a convincing relationship between ETS exposure and asthma induction, perhaps because of methodological inadequacies. Here, we tested the hypothesis that ETS inhalation would provoke an asthmatic response by overcoming normal airway tolerance to inhaled antigens. Our protocol combined daily ETS exposure with nose-only sensitization to ovalbumin. Three strains of mice were tested, each with a different level of susceptibility to airway hypersensitivity. Immunological responses were assessed by immunoglobulin production. Airway inflammation was assessed by bronchoalveolar lavage differentials and lung histopathology. Airway hyperresponsiveness was determined by methacholine challenge. The mice produced ovalbumin-specific antibodies following ovalbumin exposure in a strain-dependent manner. Only the A/J mice produced detectable levels of ovalbumin-specific immunoglobulin (Ig) E. Both A/J and BALB/c mice produced ovalbumin-specific IgG1 antibodies. The C57Bl/6 mice did not produce detectable levels of antibodies. The A/J mice also exhibited airway inflammation following ovalbumin exposure. Neither the C57Bl/6 nor the BALB/c mice exhibited signs of airway inflammation. Exposure to ETS failed to enhance ovalbumin-specific antibody production, airway inflammation, or hyperresponsiveness. Together these results indicate that ETS exposure accompanied by nose-only allergen sensitization fails to overcome aerosol tolerance in adult mice.     

Suicide and deliberate self-harm in Oxford University students over a 30-year period

Purpose  

To determine whether rates of suicide and self-harm in university students differ from those in other young people.