A prenylated dsRNA sensor protects against severe COVID-19

Inherited genetic factors can influence the severity of COVID-19, but the molecular explanation underpinning a genetic association is often unclear. Intracellular antiviral defenses can inhibit the replication of viruses and reduce disease severity. To better understand the antiviral defenses relevant to COVID-19, we used interferon-stimulated gene (ISG) expression screening to reveal that OAS1, through RNase L, potently inhibits SARS-CoV-2. We show that a common splice-acceptor SNP (Rs10774671) governs whether people express prenylated OAS1 isoforms that are membrane-associated and sense specific regions of SARS-CoV-2 RNAs, or only express cytosolic, nonprenylated OAS1 that does not efficiently detect SARS-CoV-2. Importantly, in hospitalized patients, expression of prenylated OAS1 was associated with protection from severe COVID-19, suggesting this antiviral defense is a major component of a protective antiviral response

Accuracy of three electronic apex locators in the presence of different irrigating solutions

The present study compared the accuracy of three electronic apex locators (EALs) - Elements Diagnostic®, Root ZX® and Apex DSP® - in the presence of different irrigating solutions (0.9% saline solution and 1% sodium hypochlorite). The electronic measurements were carried out by three examiners, using twenty extracted human permanent maxillary central incisors. A size 10 K file was introduced into the root canals until reaching the 0.0 mark, and was subsequently retracted to the 1.0 mark. The gold standard (GS) measurement was obtained by combining visual and radiographic methods, and was set 1 mm short of the apical foramen. Electronic length values closer to the GS (± 0.5 mm) were considered as accurate measures. Intraclass correlation coefficients (ICCs) were used to verify inter-examiner agreement. The comparison among the EALs was performed using the McNemar and Kruskal-Wallis tests (p < 0.05). The ICCs were generally high, ranging from 0.8859 to 0.9657. Similar results were observed for the percentage of electronic measurements closer to the GS obtained with the Elements Diagnostic® and the Root ZX® EALs (p > 0.05), independent of the irrigating solutions used. The measurements taken with these two EALs were more accurate than those taken with Apex DSP®, regardless of the irrigating solution used (p < 0.05). It was concluded that Elements Diagnostic® and Root ZX® apex locators are able to locate the cementum-dentine junction more precisely than Apex DSP®. The presence of irrigating solutions does not interfere with the performance of the EALs

Abordagem diagnóstica e terapêutica da toxoplasmose em gestantes e as repercussões no recém-nascido Diagnostic and therapeutic management of toxoplasmosis in pregnancy and the effect in the newborn

OBJETIVO:Avaliar a abordagem diagnóstica e terapêutica da toxoplasmose de gestantes que apresentaram IgM positiva para a doença e o acompanhamento de seus filhos em um hospital público no Rio de Janeiro, RJ. MÉTODOS: Estudo transversal retrospectivo de 2003 a 2006, realizado por meio da análise dos prontuários de 98 gestantes com sorologia IgM positiva para toxoplasmose e seus filhos (99 crianças). O seguimento das crianças com e sem infecção congênita foram analisados, assim como a apresentação clínica daquelas com infecção congênita e os testes diagnósticos utilizados para identificar a infecção pelo Toxoplasma gondii durante a gestação. RESULTADOS: O diagnóstico sorológico foi realizado em 76 pacientes no segundo e terceiro trimestre gestacional. Em 36 gestantes, a determinação dos níveis séricos de IgM foi o único teste diagnóstico realizado para infecção pelo toxoplasma. Em 49 gestantes, os índices de IgM, pela técnica ELFA, foram baixos. O teste de avidez de IgG foi realizado em 62 gestantes e somente 13 o realizaram no primeiro trimestre gestacional. O tratamento específico para toxoplasmose foi empregado em 93 gestantes. A taxa de transmissão vertical foi de 4%. Manifestações clínicas de toxoplasmose congênita foram encontradas em todas as crianças infectadas. Todas as crianças não infectadas apresentaram declínio de IgG específica para toxoplasmose ao longo do acompanhamento ambulatorial; a idade média de IgG comprovadamente negativa nessas crianças foi de 5,4 meses. CONCLUSÕES: Os resultados sugerem que uma sorologia positiva para IgM, como um único marcador sorológico para detectar infecção recente, tem um valor limitado.<br>OBJECTIVE: To analyze the diagnostic and therapeutic approach of pregnant women with positive IgM test for toxoplasmosis and the follow-up of their children in a public hospital of Rio de Janeiro, Brazil. METHODS: This cross-sectional retrospective study from 2003 to 2006 enrolled 98 pregnant women with positive IgM test for toxoplasmosis and 99 children. The follow-up of the children with or without congenital infection was reviewed, as well as the clinical presentation of those with congenital infection and the laboratory tests used to diagnose the infection by Toxoplasma gondii during pregnancy. RESULTS: Toxoplasmosis was diagnosed in the second and third trimesters of pregnancy in 76 patients. In 36 pregnant women, determination of the serum levels of IgM was the only laboratory method used to diagnose the infection. Low IgM levels analyzed by ELFA were detected in 49 pregnant women. IgG avidity test was performed in 62 patients and in 13% of them the exam was carried out during the first trimester of pregnancy. Specific treatment for toxoplasmosis was applied in 93 women. Vertical transmission rate was 4%. Clinical manifestation of congenital toxoplasmosis was found in all infected children. All non-infected children showed a decrease in IgG serum levels for toxoplasmosis during the follow-up. The mean age for negativation of IgG serum levels in these children was 5.4 months. CONCLUSIONS: Our results suggest that the use of a positive IgM test to toxoplasmosis as the only antibody marker to detect recent infection has a limited value