Frequency, kinetics and determinants of viable SARS-CoV-2 in bioaerosols from ambulatory COVID-19 patients infected with the Beta, Delta or Omicron variants

Airborne transmission of SARS-CoV-2 aerosol remains contentious. Importantly, whether cough or breath-generated bioaerosols can harbor viable and replicating virus remains largely unclarified. We performed size-fractionated aerosol sampling (Andersen cascade impactor) and evaluated viral culturability in human cell lines (infectiousness), viral genetics, and host immunity in ambulatory participants with COVID-19. Sixty-one percent (27/44) and 50% (22/44) of participants emitted variant-specific culture-positive aerosols <10μm and <5μm, respectively, for up to 9 days after symptom onset. Aerosol culturability is significantly associated with lower neutralizing antibody titers, and suppression of transcriptomic pathways related to innate immunity and the humoral response. A nasopharyngeal Ct <17 rules-in ~40% of aerosol culture-positives and identifies those who are probably highly infectious. A parsimonious three transcript blood-based biosignature is highly predictive of infectious aerosol generation (PPV > 95%). There is considerable heterogeneity in potential infectiousness i.e., only 29% of participants were probably highly infectious (produced culture-positive aerosols <5μm at ~6 days after symptom onset). These data, which comprehensively confirm variant-specific culturable SARS-CoV-2 in aerosol, inform the targeting of transmission-related interventions and public health containment strategies emphasizing improved ventilation.

Functional annotation of rare structural variation in the human brain

Structural variants (SVs) contribute to many disorders, yet, functionally annotating them remains a major challenge. Here, we integrate SVs with RNA-sequencing from human post-mortem brains to quantify their dosage and regulatory effects. We show that genic and regulatory SVs exist at significantly lower frequencies than intergenic SVs. Functional impact of copy number variants (CNVs) stems from both the proportion of genic and regulatory content altered and loss-of-function intolerance of the gene. We train a linear model to predict expression effects of rare CNVs and use it to annotate regulatory disruption of CNVs from 14,891 independent genome-sequenced individuals. Pathogenic deletions implicated in neurodevelopmental disorders show significantly more extreme regulatory disruption scores and if rank ordered would be prioritized higher than using frequency or length alone. This work shows the deleteriousness of regulatory SVs, particularly those altering CTCF sites and provides a simple approach for functionally annotating the regulatory consequences of CNVs.

Plant-based formulation for bronchial asthma: a controlled clinical trial to compare its efficacy with oral salbutamol and theophylline

BACKGROUND

Plant-based medicine is the 3rd most popular choice of both adults (11%) and children (6%) suffering from Asthma. While several plant-based formulations have been reported for the treatment of asthma in the past, many authors have published their reservations on clinical trials carried out using complementary and alternative medicines.

OBJECTIVES

The authors desired to eliminate the shortcomings of the earlier clinical trials carried out by many investigators in a structured study. Therefore, a 12-week randomized double-blind placebo-controlled clinical study was conducted to investigate the efficacy of a plant-based formulation (DCBT4567-Astha-15) in comparison with oral salbutamol, salbutamol + theophylline and a matching placebo in patients with reversible asthma.

METHODS

Ninety-four patients between 15 and 50 years of age, showing 15% improvement in forced expiratory volume in 1 s (FEV(1)) 15 min after a bronchial challenge of inhaled salbutamol (200 microg) were recruited, and the end point of the study was determined as a 15% improvement in FEV(1) and clinical symptoms like dyspnoea, wheezing, cough, expectoration, disability, sleep disturbances and respiration rate.

RESULTS

DCBT4567-Astha-15, salbutamol and salbutamol + theophylline patients showed statistically significant improvement in FEV(1), while placebo patients did not show any improvement. Fifty percent of DCBT4567-Astha-15, 48% of salbutamol, 58% of salbutamol + theophylline and 26% of placebo patients showed the desired 15% improvement in FEV(1). Improved mean FEV(1) values at the end of the trial indicated that the salbutamol - theophylline combination was superior followed by salbutamol and DCBT4567-Astha-15. Clinical symptoms like dyspnoea, wheezing, cough, expectoration, disability, and sleep disturbances were significantly reduced in DCBT4567-Astha-15 patients compared to patients of the other three arms.

CONCLUSIONS

DCBT4567-Astha-15 was as efficacious as salbutamol (12 mg/day) or salbutamol (12 mg/day) in combination with theophylline (200 mg/day) in the treatment of reversible asthmatics. Quality of life of patients also improved with DCBT4567-Astha-15 drug treatment.

Effect of timing of ondansetron administration on incidence of postoperative vomiting in paediatric strabismus surgery

This prospective, randomized, double-blinded study evaluated the effect of the timing of ondansetron administration on its antiemetic efficacy in children undergoing elective strabismus surgery. One hundred and twenty children aged one to 15 years, ASA physical status 1 or 2, were randomly allocated to receive intravenous ondansetron 100 micrograms/kg either at induction (Group 1) or at the end of the surgery (Group 2). All patients had general anaesthesia induced and maintained with nitrous oxide and halothane, muscle relaxation with vecuronium, endotracheal intubation, reversal with neostigmine and glycopyrrolate, and pethidine 0.5 mg/kg analgesia. Episodes of nausea and vomiting were evaluated at 0 to 2, 2 to 6 and 6 to 24 hour intervals by a blinded observer. Demographic data, duration of anaesthesia, type of surgery, incidence of previous postoperative nausea or vomiting and motion sickness and number of patients who developed oculocardiac reflex requiring atropine treatment were similar in both groups. The incidence of emesis in the first 24 hours following surgery was similar in both groups (35% Group 1, 33.3% Group 2, P = 1.00). Severity of emesis (median number of emetic episodes, rescue antiemetic requirement and mean time to the onset of first episode of emesis) and mean time to discharge from the post anaesthesia care unit were also similar in the two groups. We conclude that the timing of ondansetron administration either before or after the surgical manipulation of extraocular muscles had similar antiemetic efficacy following strabismus surgery in children.