Routine use of the sniffing position appears to provide no significant advantage over simple head extension for tracheal intubation in this setting. The sniffing position appears to be advantageous in obese and head extension-limited patients.
The understanding of HTLV-induced disease is hampered by the lack of a suitable animal model allowing the study of both viral replication and leukemogenesis in vivo. Although valuable information has been obtained in different species, such as rabbits, mice, rats, and monkeys, none of these systems was able to conciliate topics as different as viral infectivity, propagation within the host, and generation of leukemic cells. An alternate strategy is based on the understanding of diseases induced by viruses closely related to HTLV-1, like bovine leukemia virus (BLV). Both viruses indeed belong to the same subfamily of retroviruses, harbor a similar genomic organization, and infect and transform cells of the hematopoietic system. The main advantage of the BLV system is that it allows direct experimentation in two different species, cattle and sheep.
Background Limited data are available regarding antiviral therapy efficacy in most severe patients under mechanical ventilation for Covid-19-related acute respiratory distress syndrome (ARDS). Methods Comparison of antiviral strategies (none, hydroxychloroquine (OHQ), lopinavir/ritonavir (L/R), others (combination or remdesivir) in an observational multicentre cohort of patients with moderate-to-severe Covid-19 ARDS. The primary endpoint was the number of day 28 ventilator-free days (VFD). Patients who died before d28 were considered as having 0 VFD. The variable was dichotomized into “patients still ventilated or dead at day 28” versus “patients weaned and alive at day 28”. Results We analyzed 415 patients (85 treated with standard of care (SOC), 57 with L/R, 220 with OHQ, and 53 others). The median number of d28-VFD was 0 (IQR 0–13) and differed between groups (P = 0.03), SOC patients having the highest d28-VFD. After adjustment for age, sex, Charlson Comorbidity Index, PaO2/FiO2 ratio and plateau pressure and accounting for center effect with a generalized linear mixed model, none of the antiviral strategies increased the chance of being alive and weaned from MV at day 28 compared to the SOC strategy (OR 0.48 CI95% (0.18–1.25); OR 0.96 (0.47–2.02) and OR 1.43 (0.53–4.04) for L/R, OHQ and other treatments, respectively). Acute kidney injury during ICU stay was frequent (55%); its incidence was higher in patients receiving lopinavir (66 vs 53%, P = 0.03). After adjustment for age, sex, BMI, chronic hypertension and chronic renal disease, the use of L/R was associated with an increased risk of renal replacement therapy (RRT). (OR 2.52 CI95% 1.16–5.59). Conclusion In this multicentre observational study of moderate-to-severe Covid-19 ARDS patients, we did not observe any benefit among patients treated with OHQ or L/R compared with SOC. The use of L/R treatment was associated with an increased need for RRT. Take home message Neither hydroxychloroquine nor lopinavir/ritonavir as COVID-19 antiviral treatment is associated with higher ventilator-free days at day 28 when compared with standard of care (no antiviral treatment) in ICU patients under invasive mechanical ventilation. Lopinavir/ritonavir is associated with an increased risk of renal replacement therapy requirement. Tweet COVID-19: Insights from ARDS cohort: no signal of efficacy of any antiviral drugs. Lopinavir/ritonavir may be associated with need for RRT
G4 and p13II are accessory proteins encoded by the X region of bovine leukemia virus and human T-cell leukemia virus type 1 (HTLV-1), respectively. Disruption of the G4 and p13 II open reading frames interferes with viral spread in animal model systems, indicating that the corresponding proteins play a key role in viral replication. In addition, G4 is oncogenic in primary cell cultures and is absolutely required for efficient onset of leukemogenesis in sheep. To gain insight into the function of these proteins, we utilized the yeast two-hybrid system to identify protein partners of G4. Results revealed that G4 interacts with farnesyl pyrophosphate synthetase (FPPS), a protein involved in the mevalonate/squalene pathway and in synthesis of FPP, a substrate required for prenylation of Ras. The specificity of the interaction was verified by glutathione S-transferase (GST) pull-down assays and by coimmunoprecipitation experiments. Furthermore, confocal microscopy showed that the subcellular localization of G4 was profoundly affected by FPPS. The G4 protein itself was not prenylated, at least in rabbit reticulocyte lysate-based assays. The domain of G4 required for binding to FPPS was restricted to an amphipathic ␣-helix rich in arginine residues. Subtle mutation of this ␣-helix abrogated G4 oncogenic potential in vitro, providing a biological relevance for FPPS-G4 complex formation in cells. Finally, HTLV-1 p13 II was also found to specifically interact with FPPS (in yeast as well as in GST pull-down assays) and to colocalize with G4 in mitochondria, suggesting a functional analogy between these oncoviral accessory proteins. Identification of FPPS as a molecular partner for p13 II and G4 accessory proteins opens new prospects for treatment of retrovirus-induced leukemia.Bovine leukemia virus (BLV), a naturally occurring B-lymphotropic retrovirus, is a member of the Oncovirinae subfamily and belongs to the Deltaretrovirus genus, which also includes the human T-cell leukemia virus types 1 and 2 (HTLV-1 and -2) and the simian T-cell leukemia viruses. All these viruses share a similar genomic organization and induce related pathologies in their respective host species (reviewed in references 44 and 54). In addition to the gag, pol, and env genes, deltaretroviruses contain an X region, located between the env sequences and the 3Ј long terminal repeat. At least four proteins are encoded by this genomic region; perhaps the bestcharacterized ones are the Tax transactivator and the Rex posttranscriptional regulator. These two proteins are expressed from a single double-spliced RNA and are considered to be essential since their mutation abrogates viral infectivity or pathogenicity (39,40,52). Two additional open reading frames are transcribed from the X region, and the corresponding mRNAs potentially encode accessory proteins: R3 and G4 for BLV, p12 I /p13 II /p30 II for HTLV-1, and p10
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.