Endogenous interferon-beta but not interferon-alpha or interferon-lambda levels in upper respiratory tract predict clinical outcome in critical COVID-19 patients independent of viral load

Although the subject of intensive preclinical and clinical research, controversy on the protective vs. deleterious effect of interferon (IFN) in COVID-19 remains. Some apparently conflicting results are likely due to the intricacy of IFN subtypes (type I: IFN-alpha/beta, type III: IFN-lambda), timing and mode of administration (nebulized/subcutaneous) and clinical groups targeted (asymptomatic/mild, moderate, severe/critical COVID-19). Within the COntAGIouS (COvid-19 Advanced Genetic and Immunologic Sampling) clinical trial, we investigated endogenous type I and type III IFNs in nasal mucosa as possible predictors of clinical outcome in critical patients, as well as their correlation to SARS-CoV-2 viral load, using nCounter technology. We found that endogenous IFN-beta expression in the nasal mucosa predicts clinical outcome, independent of viral replication or Apache II score, and should be considered as a prognostic tool in a precision medicine approach of IFN therapy in COVID-19 clinical management.

Mechanical ventilation affects respiratory microbiome of COVID-19 patients and its interactions with the host

Understanding the pathology of COVID-19 is a global research priority. Early evidence suggests that the respiratory microbiome may be playing a role in disease progression, yet current studies report contradictory results. Here, we examine potential confounders in COVID-19 respiratory microbiome studies by analyzing the upper (n=58) and lower (n=35) respiratory tract microbiome in well-phenotyped COVID-19 patients and controls combining microbiome sequencing, viral load determination, and immunoprofiling. We found that time in the intensive care unit and the type of oxygen support, both of which are associated to additional treatments such as antibiotic usage, explained the most variation within the upper respiratory tract microbiome, while SARS-CoV-2 viral load had a reduced impact. Specifically, mechanical ventilation was linked to altered community structure, lower species- and higher strain-level diversity, and significant shifts in oral taxa previously associated with COVID-19. Single-cell transcriptomic analysis of the lower respiratory tract of mechanically ventilated COVID-19 patients identified specific oral bacteria, different to those observed in controls. These oral taxa were found physically associated with proinflammatory immune cells, which showed higher levels of inflammatory markers. Overall, our findings suggest confounders are driving contradictory results in current COVID-19 microbiome studies and careful attention needs to be paid to ICU stay and type of oxygen support, as bacteria favored in these conditions may contribute to the inflammatory phenotypes observed in severe COVID-19 patients.

A pilot study comparing bovine mesenteric artery and expanded polytetrafluoroethylene grafts as non-autogenous hemodialysis options.

BACKGROUND: Many dialysis patients do not have the necessary conditions for construction of a native arteriovenous fistula (AVF). Expanded Polytetrafluoroethylene (ePTFE) vascular prostheses are the most widely-used option, but it is known that they are inferior to native vein AVFs. OBJECTIVES: To identify a graft with superior performance to ePTFE, comparing their results with those of AVFs made from bovine mesenteric arteries treated with L-Hydro technology (Labcor Laboratories ®). METHODS: A prospective and controlled study of 10 patients with AVFs constructed with ePTFE and 10 patients with L-Hydro bioprostheses, matched for comorbidities. The variables studied were: primary patency, assisted primary patency, and secondary patency, surgical manipulability, and prevalence of infections. The performance of prostheses was assessed by duplex-scan and repeated consultations with health professionals at hemodialysis clinics. The chi-square test was used for statistical analysis. RESULTS: After 1 year of postoperative follow-up, secondary and primary patency rates were higher for L-Hydro than ePTFE AVFs. Fewer interventions were needed to maintain AVF patency in the L-Hydro AVF group. The most common complication was graft thrombosis, which was more frequent in the ePTFE group. While the figures indicate more favorable outcomes in the L-Hydro AVFs, this could not be confirmed with the statistical treatment employed. CONCLUSIONS: The L-Hydro graft appears to be a valuable alternative option for AVFs, since it seems to require fewer interventions to maintain patency when compared to ePTFE grafts.

White grub (Coleoptera: Melolonthidae) mortality induced by Ophiocordyceps melolonthae / Mortalidade em corós (Coleoptera: Melolonthidae) induzida por Ophiocordyceps melolonthae

ABSTRACT: The occurrence of white grub roots in soybean crops in the South of Brazil has gradually increased. However, there is not information on the biological control of grubs by entomopathogenic fungi. This study aimed to induce infection by Ophiocordyceps melolonthae and analyze longevity in Cyclocephala modesta and Dyscinetus gagates larvae (Coleoptera: Melolonthidae). In the laboratory, Cyclocephala modesta and Dyscinetus gagates had a mortality rate of 85% and 75%, respectively.

RESUMO: A ocorrência de corós-praga de raízes em lavoura de soja, no Sul do Brasil, tem gradualmente aumentado. Entretanto, não há informação sobre controle biológico de corós por fungos entomopatogênicos. Este estudo tem o objetivo de induzir a infecção por Ophiocordyceps melolonthae e analisar a longevidade em larvas de Cyclocephala modesta e Dyscinetus gagates (Coleoptera: Melolonthidae). Em laboratório, Cyclocephala modesta e Dyscinetus gagates apresentaram uma taxa de mortalidade de 85% e 75%, respectivamente.

Aneurisma de veia poplítea: relato de caso e revisão da literatura / Popliteal vein aneurysm: case report and literature review

Os aneurismas venosos são raros, porém causam complicações tromboembólicas. Na maioria das vezes, são encontrados como achados de exame físico ou de imagem. Os aneurismas sintomáticos de veia poplítea são tratados por reparo cirúrgico, devido ao alto risco de recorrência de embolia pulmonar. A técnica mais utilizada é a aneurismectomia tangencial com venorrafia lateral. Na impossibilidade de se empregar esta técnica, faz-se a ressecção com reconstrução venosa. Os autores relatam o caso de uma paciente com aneurisma de veia poplítea, cujo diâmetro era de 44 mm, submetida à aneurismectomia tangencial e venorrafia lateral, com sucesso.

Venous aneurysms are rare; however, they are potential causes of thromboembolism. Most cases are found as clinical examination or by imaging methods. Symptomatic aneurysms of the popliteal vein are treated by surgical repair due to the high risk of recurrent pulmonary embolism. The most widely used procedure is tangential aneurysmectomy and lateral venorrhaphy. If this technique is not possible, the aneurysm should be removed and venous reconstruction should be performed. The authors report the case of a patient with popliteal vein aneurysm measuring 44 mm in diameter which was successfully treated by tangential aneurysmectomy and lateral venorrhaphy.