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1.
Wiad Lek ; 77(2): 305-310, 2024.
Article in English | MEDLINE | ID: mdl-38592994

ABSTRACT

OBJECTIVE: Aim: To determine the possibility of predicting adverse cardiovascular events based on the analysis of clinical and instrumental research methods, as well as sST2 in patients after myocardial infarction. PATIENTS AND METHODS: Materials and Methods: The study included 64 patients who suffered an acute myocardial infarction and underwent PCI with balloon angioplasty and stenting of the infarct-related vessel in the acute period. The predictors of adverse cardiovascular events were assessed events during 1 year of observation. Indicators of echocardiography and coronary angiography were assessed and concentrations sST2. RESULTS: Results: A worse prognosis was associated with intermediate ejection fraction (EF) (odds ratio (OR)=3.981, p<0.05), left aneurysm ventricle (LV) (OR=29.5, p<0.05), high concentrations of sST2 (OR=1.017, p<0.05) and scores on the Syntax scale (OR=1.001, p<0.05). CONCLUSION: Conclusions: In patients who underwent percutaneous coronary intervention for myocardial infarction, adverse outcome during the next 2 years is associated with coronary and echocardiographic parameters, as well as biochemical indicators of myocardial stress and fibrosis. HF patients with intermediate EF, LV aneurysm, high sST2 concentrations, and high Syntax scores have the worst prognosis.


Subject(s)
Aneurysm , Angioplasty, Balloon, Coronary , Myocardial Infarction , Percutaneous Coronary Intervention , Humans , Prognosis , Treatment Outcome , Ventricular Function, Left
2.
J Virol ; 98(5): e0190123, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38629840

ABSTRACT

Many viruses inhibit general host gene expression to limit innate immune responses and gain preferential access to the cellular translational apparatus for their protein synthesis. This process is known as host shutoff. Influenza A viruses (IAVs) encode two host shutoff proteins: nonstructural protein 1 (NS1) and polymerase acidic X (PA-X). NS1 inhibits host nuclear pre-messenger RNA maturation and export, and PA-X is an endoribonuclease that preferentially cleaves host spliced nuclear and cytoplasmic messenger RNAs. Emerging evidence suggests that in circulating human IAVs NS1 and PA-X co-evolve to ensure optimal magnitude of general host shutoff without compromising viral replication that relies on host cell metabolism. However, the functional interplay between PA-X and NS1 remains unexplored. In this study, we sought to determine whether NS1 function has a direct effect on PA-X activity by analyzing host shutoff in A549 cells infected with wild-type or mutant IAVs with NS1 effector domain deletion. This was done using conventional quantitative reverse transcription polymerase chain reaction techniques and direct RNA sequencing using nanopore technology. Our previous research on the molecular mechanisms of PA-X function identified two prominent features of IAV-infected cells: nuclear accumulation of cytoplasmic poly(A) binding protein (PABPC1) and increase in nuclear poly(A) RNA abundance relative to the cytoplasm. Here we demonstrate that NS1 effector domain function augments PA-X host shutoff and is necessary for nuclear PABPC1 accumulation. By contrast, nuclear poly(A) RNA accumulation is not dependent on either NS1 or PA-X-mediated host shutoff and is accompanied by nuclear retention of viral transcripts. Our study demonstrates for the first time that NS1 and PA-X may functionally interact in mediating host shutoff.IMPORTANCERespiratory viruses including the influenza A virus continue to cause annual epidemics with high morbidity and mortality due to the limited effectiveness of vaccines and antiviral drugs. Among the strategies evolved by viruses to evade immune responses is host shutoff-a general blockade of host messenger RNA and protein synthesis. Disabling influenza A virus host shutoff is being explored in live attenuated vaccine development as an attractive strategy for increasing their effectiveness by boosting antiviral responses. Influenza A virus encodes two proteins that function in host shutoff: the nonstructural protein 1 (NS1) and the polymerase acidic X (PA-X). We and others have characterized some of the NS1 and PA-X mechanisms of action and the additive effects that these viral proteins may have in ensuring the blockade of host gene expression. In this work, we examined whether NS1 and PA-X functionally interact and discovered that NS1 is required for PA-X to function effectively. This work significantly advances our understanding of influenza A virus host shutoff and identifies new potential targets for therapeutic interventions against influenza and further informs the development of improved live attenuated vaccines.


Subject(s)
Influenza A virus , Viral Nonstructural Proteins , Humans , A549 Cells , Host-Pathogen Interactions , Influenza A virus/genetics , Influenza, Human/virology , Influenza, Human/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Viral Nonstructural Proteins/metabolism , Viral Nonstructural Proteins/genetics , Virus Replication , Host-Parasite Interactions
3.
Viruses ; 16(2)2024 01 31.
Article in English | MEDLINE | ID: mdl-38399988

ABSTRACT

Viruses evolve many strategies to ensure the efficient synthesis of their proteins. One such strategy is the inhibition of the integrated stress response-the mechanism through which infected cells arrest translation through the phosphorylation of the alpha subunit of the eukaryotic translation initiation factor 2 (eIF2α). We have recently shown that the human common cold betacoronavirus OC43 actively inhibits eIF2α phosphorylation in response to sodium arsenite, a potent inducer of oxidative stress. In this work, we examined the modulation of integrated stress responses by OC43 and demonstrated that the negative feedback regulator of eIF2α phosphorylation GADD34 is strongly induced in infected cells. However, the upregulation of GADD34 expression induced by OC43 was independent from the activation of the integrated stress response and was not required for the inhibition of eIF2α phosphorylation in virus-infected cells. Our work reveals a complex interplay between the common cold coronavirus and the integrated stress response, in which efficient viral protein synthesis is ensured by the inhibition of eIF2α phosphorylation but the GADD34 negative feedback loop is disrupted.


Subject(s)
Betacoronavirus , Common Cold , Humans , Betacoronavirus/metabolism , Protein Phosphatase 1/metabolism , Proteins/metabolism , Phosphorylation , Protein Biosynthesis , Eukaryotic Initiation Factor-2/metabolism , eIF-2 Kinase/genetics
4.
Alcohol Clin Exp Res (Hoboken) ; 47(12): 2233-2247, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38151780

ABSTRACT

BACKGROUND: Excess reactive oxygen species generated by NADPH oxidase 2 (Nox2) in response to ethanol exposure mediate aspects of skeletal toxicity including increased osteoclast differentiation and activity. Because perturbation of chondrocyte differentiation in the growth plate by ethanol could be prevented by dietary antioxidants, we hypothesized that Nox2 in the growth plate was involved in ethanol-associated reductions in longitudinal bone growth. METHODS: Nox2 conditional knockout mice were generated, where the essential catalytic subunit of Nox2, cytochrome B-245 beta chain (Cybb), is deleted in chondrocytes using a Cre-Lox model with Cre expressed from the collagen 2a1 promoter (Col2a1-Cre). Wild-type and Cre-Lox mice were fed an ethanol Lieber-DeCarli-based diet or pair-fed a control diet for 8 weeks. RESULTS: Ethanol treatment significantly reduced the number of proliferating chondrocytes in the growth plate, enhanced bone marrow adiposity, shortened femurs, reduced body length, reduced cortical bone volume, and decreased mRNA levels of a number of osteoblast and chondrocyte genes. Conditional knockout of Nox2 enzymatic activity in chondrocytes did not consistently prevent any ethanol effects. Rather, knockout mice had fewer proliferating chondrocytes than wild-type mice in both the ethanol- and control-fed animals. Additional analysis of tibia samples from Nox4 knockout mice showed that loss of Nox4 activity also reduced the number of proliferating chondrocytes and altered chondrocyte size in the growth plate. CONCLUSIONS: Although Nox enzymatic activity regulates growth plate development, ethanol-associated disruption of the growth plate morphology is independent of ethanol-mediated increases in Nox2 activity.

5.
J Org Chem ; 88(1): 163-171, 2023 Jan 06.
Article in English | MEDLINE | ID: mdl-36520999

ABSTRACT

The reaction of trimethyl(trifluoromethyl)silane-tetrabutylammonium difluorotriphenylsilicate (CF3SiMe3-TBAT) with a series of imidazoles gives products of the formal difluorocarbene insertion into the C-H bond at the C-2 position (i.e., C-difluoromethylation). According to NMR spectra, the corresponding 2-(trimethylsilyl)difluoromethyl-substituted derivatives are likely formed as the intermediates in the reaction, and then, they slowly convert to 2-difluoromethyl-substituted imidazoles. Quantum chemical calculations of two plausible reaction mechanisms indicate that it proceeds through the intermediate imidazolide anion stabilized through the interaction with solvent molecules and counterions. In the first proposed mechanism, the anion reacts with difluorocarbene without an activation barrier, and then, the CF2 moiety of the adduct attacks the CF3SiMe3 molecule. After the elimination of the CF3 anion, 2-(trimethylsilyl)difluromethyl-substituted imidazole is formed. Another possible reaction pathway includes silylation of imidazolide anion at the N-3 atom, followed by the barrierless addition of difluorocarbene at the C-2 atom and then by 1,3-shift of the SiMe3 group from N-3 to the carbon atom of the CF2 moiety. Both proposed mechanisms do not include steps with high activation barriers.

6.
PLoS Pathog ; 18(12): e1011041, 2022 12.
Article in English | MEDLINE | ID: mdl-36534661

ABSTRACT

Stress granules (SGs) are cytoplasmic condensates that often form as part of the cellular antiviral response. Despite the growing interest in understanding the interplay between SGs and other biological condensates and viral replication, the role of SG formation during coronavirus infection remains poorly understood. Several proteins from different coronaviruses have been shown to suppress SG formation upon overexpression, but there are only a handful of studies analyzing SG formation in coronavirus-infected cells. To better understand SG inhibition by coronaviruses, we analyzed SG formation during infection with the human common cold coronavirus OC43 (HCoV-OC43) and the pandemic SARS-CoV2. We did not observe SG induction in infected cells and both viruses inhibited eukaryotic translation initiation factor 2α (eIF2α) phosphorylation and SG formation induced by exogenous stress. Furthermore, in SARS-CoV2 infected cells we observed a sharp decrease in the levels of SG-nucleating protein G3BP1. Ectopic overexpression of nucleocapsid (N) and non-structural protein 1 (Nsp1) from both HCoV-OC43 and SARS-CoV2 inhibited SG formation. The Nsp1 proteins of both viruses inhibited arsenite-induced eIF2α phosphorylation, and the Nsp1 of SARS-CoV2 alone was sufficient to cause a decrease in G3BP1 levels. This phenotype was dependent on the depletion of cytoplasmic mRNA mediated by Nsp1 and associated with nuclear accumulation of the SG-nucleating protein TIAR. To test the role of G3BP1 in coronavirus replication, we infected cells overexpressing EGFP-tagged G3BP1 with HCoV-OC43 and observed a significant decrease in virus replication compared to control cells expressing EGFP. The antiviral role of G3BP1 and the existence of multiple SG suppression mechanisms that are conserved between HCoV-OC43 and SARS-CoV2 suggest that SG formation may represent an important antiviral host defense that coronaviruses target to ensure efficient replication.


Subject(s)
COVID-19 , Coronavirus OC43, Human , Humans , Coronavirus OC43, Human/metabolism , COVID-19/metabolism , Cytoplasmic Granules/metabolism , DNA Helicases/metabolism , Poly-ADP-Ribose Binding Proteins/genetics , Poly-ADP-Ribose Binding Proteins/metabolism , RNA Helicases/genetics , RNA Helicases/metabolism , RNA Recognition Motif Proteins/metabolism , RNA, Viral/metabolism , SARS-CoV-2/metabolism , Stress Granules
7.
PLoS Pathog ; 18(9): e1010832, 2022 09.
Article in English | MEDLINE | ID: mdl-36121863

ABSTRACT

There is an outstanding need for broadly acting antiviral drugs to combat emerging viral diseases. Here, we report that thiopurines inhibit the replication of the betacoronaviruses HCoV-OC43 and SARS-CoV-2. 6-Thioguanine (6-TG) disrupted early stages of infection, limiting accumulation of full-length viral genomes, subgenomic RNAs and structural proteins. In ectopic expression models, we observed that 6-TG increased the electrophoretic mobility of Spike from diverse betacoronaviruses, matching the effects of enzymatic removal of N-linked oligosaccharides from Spike in vitro. SARS-CoV-2 virus-like particles (VLPs) harvested from 6-TG-treated cells were deficient in Spike. 6-TG treatment had a similar effect on production of lentiviruses pseudotyped with SARS-CoV-2 Spike, yielding pseudoviruses deficient in Spike and unable to infect ACE2-expressing cells. Together, these findings from complementary ectopic expression and infection models strongly indicate that defective Spike trafficking and processing is an outcome of 6-TG treatment. Using biochemical and genetic approaches we demonstrated that 6-TG is a pro-drug that must be converted to the nucleotide form by hypoxanthine phosphoribosyltransferase 1 (HPRT1) to achieve antiviral activity. This nucleotide form has been shown to inhibit small GTPases Rac1, RhoA, and CDC42; however, we observed that selective chemical inhibitors of these GTPases had no effect on Spike processing or accumulation. By contrast, the broad GTPase agonist ML099 countered the effects of 6-TG, suggesting that the antiviral activity of 6-TG requires the targeting of an unknown GTPase. Overall, these findings suggest that small GTPases are promising targets for host-targeted antivirals.


Subject(s)
COVID-19 , Monomeric GTP-Binding Proteins , Prodrugs , Angiotensin-Converting Enzyme 2 , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Humans , Hypoxanthine Phosphoribosyltransferase/metabolism , Monomeric GTP-Binding Proteins/metabolism , Nucleotides/metabolism , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/metabolism , Thioguanine , Virion/metabolism
8.
Preprint in English | bioRxiv | ID: ppbiorxiv-483772

ABSTRACT

There is an outstanding need for broadly acting antiviral drugs to combat emerging viral diseases. Here, we report that thiopurines inhibit the replication of the betacoronaviruses HCoV-OC43 and SARS-CoV-2, and to a lesser extent, the alphacoronavirus HCoV-229E. 6-Thioguanine (6-TG) disrupted early stages of infection, limiting synthesis of full-length and subgenomic HCoV RNAs. Furthermore, consistent with our previous report on the effects of thiopurines on influenza A virus glycoproteins, we observed that 6-TG inhibited accumulation of Spike glycoproteins from diverse HCoVs. Specifically, 6-TG treatment decreased the accumulation of Spike proteins and increased their electrophoretic mobility, consistent with Spike migration following the enzymatic removal of N-linked oligosaccharides with Peptide:N-glycosidase F (PNGaseF). SARS-CoV-2 virus-like particles (VLPs) harvested from 6-TG-treated cells were deficient in Spike. 6-TG treatment had a similar effect on lentiviruses pseudotyped with SARS-CoV-2 Spike; lentiviruses could be harvested from cell supernatants but were deficient in Spike and unable to infect human cells bearing ACE2 receptors. Together, these findings from complementary ectopic expression and infection models strongly indicate that defective Spike trafficking and processing is an outcome of 6-TG treatment. At low micromolar doses, the primary known mode of action of 6-TG is selective inhibition of the small GTPase Rac1. However, we observed that selective chemical inhibitors of the small GTPases Rac1, CDC42 and Rho had no effect on Spike processing and accumulation. The GTPase agonist ML099 countered the effects of 6-TG, suggesting that an unknown GTPase could be the relevant 6-TG-target protein involved in regulating Spike processing and accumulation. Overall, these findings provide important clues about the mechanism of action of a candidate antiviral that can broadly target HCoVs and suggest that small GTPases are promising targets for host-targeted antivirals. AUTHOR SUMMARYThe COVID-19 pandemic has ignited efforts to repurpose existing drugs as safe and effective antivirals. Rather than directly inhibiting viral enzymes, host-targeted antivirals inhibit host cell processes to indirectly impede viral replication and/or stimulate antiviral responses. Here, we describe a new antiviral mechanism of action for the FDA-approved thiopurine 6-thioguanine. We demonstrate that this thiopurine is a pro-drug that must be metabolized by host enzymes to gain antiviral activity. We show that it can inhibit the replication of several human coronaviruses, including SARS-CoV-2, at least in part by interfering with the processing and accumulation of Spike glycoproteins, thereby impeding assembly of infectious progeny viruses. We provide evidence implicating host cell GTPase enzymes in the antiviral mechanism of action.

9.
J Virol ; 95(11)2021 05 10.
Article in English | MEDLINE | ID: mdl-33762409

ABSTRACT

Influenza A viruses (IAVs) utilize host shutoff mechanisms to limit antiviral gene expression and redirect translation machinery to the synthesis of viral proteins. Previously, we showed that IAV replication is sensitive to protein synthesis inhibitors that block translation initiation and induce formation of cytoplasmic condensates of untranslated messenger ribonucleoprotein complexes called stress granules (SGs). In this study, using an image-based high-content screen, we identified two thiopurines, 6-thioguanine (6-TG) and 6-thioguanosine (6-TGo), that triggered SG formation in IAV-infected cells and blocked IAV replication in a dose-dependent manner without eliciting SG formation in uninfected cells. 6-TG and 6-TGo selectively disrupted the synthesis and maturation of IAV glycoproteins hemagglutinin (HA) and neuraminidase (NA) without affecting the levels of the viral RNAs that encode them. By contrast, these thiopurines had minimal effect on other IAV proteins or the global host protein synthesis. Disruption of IAV glycoprotein accumulation by 6-TG and 6-TGo correlated with activation of unfolded protein response (UPR) sensors activating transcription factor-6 (ATF6), inositol requiring enzyme-1 (IRE1) and PKR-like endoplasmic reticulum kinase (PERK), leading to downstream UPR gene expression. Treatment of infected cells with the chemical chaperone 4-phenylbutyric acid diminished thiopurine-induced UPR activation and partially restored the processing and accumulation of HA and NA. By contrast, chemical inhibition of the integrated stress response downstream of PERK restored accumulation of NA monomers but did not restore processing of viral glycoproteins. Genetic deletion of PERK enhanced the antiviral effect of 6-TG without causing overt cytotoxicity, suggesting that while UPR activation correlates with diminished viral glycoprotein accumulation, PERK could limit the antiviral effects of drug-induced ER stress. Taken together, these data indicate that 6-TG and 6-TGo are effective host-targeted antivirals that trigger the UPR and selectively disrupt accumulation of viral glycoproteins.IMPORTANCESecreted and transmembrane proteins are synthesized in the endoplasmic reticulum (ER), where they are folded and modified prior to transport. Many viruses rely on the ER for the synthesis and processing of viral glycoproteins that will ultimately be incorporated into viral envelopes. Viral burden on the ER can trigger the unfolded protein response (UPR). Much remains to be learned about how viruses co-opt the UPR to ensure efficient synthesis of viral glycoproteins. Here, we show that two FDA-approved thiopurine drugs, 6-TG and 6-TGo, induce the UPR, which represents a previously unrecognized effect of these drugs on cell physiology. This thiopurine-mediated UPR activation blocks influenza virus replication by impeding viral glycoprotein accumulation. Our findings suggest that 6-TG and 6-TGo may have broad antiviral effect against enveloped viruses that require precise tuning of the UPR to support viral glycoprotein synthesis.

10.
Rev. salud pública ; 22(6): e200, nov.-dic. 2020.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1252088

ABSTRACT

RESUMEN La crisis sanitaria mundial que enfrenta el mundo debido al COVID-19 tiene como característica principal que afecta la población más vulnerable. La principal vía de contagio de esta enfermedad es la transmisión aérea debido al contacto social. Los países adoptaron una serie de intervenciones focalizadas para mitigar las consecuencias derivadas de esta pandemia e impactar significativamente en el bienestar de las personas. No obstante, se deben fortalecer acciones que favorezcan la capacidad resolutiva en el primer nivel de atención, especialmente, en poblaciones de alta vulnerabilidad, entre ellas, las personas en situación de discapacidad, cuyas circunstancias tienden a complicarse. La rehabilitación basada en comunidad ha sido una estrategia de gran impacto social que integra una serie de factores tanto individuales como colectivos. La eficacia y efectividad de la participación intersectorial, comunitaria y de los Gobiernos locales, así como la gestión de los diferentes agentes comunitarios para darle continuidad a los procesos de atención en salud son pertinentes para amortiguar situaciones de alta complejidad que alteran, en mayor medida, el bienestar de todas las personas. Además, contribuyen a potencializar acciones para gestionar el sistema de salud.


ABSTRACT As main feature, the global health crisis due to COVID-19 affects the most vulnerable groups of people. The main way of contagion of this disease is the airway transmission by social contact. Countries take steps to reduce the consequences of the pandemic and significantly improve the well-being of the people. However, they must boost measurements to support the capacity to resolve situations at the first level of assistance, mainly for the people that are so vulnerable: persons with disabilities, that get everyday worse. The Community Based Rehabilitation has been a strategy that group together collective and individual factors. The effectiveness and efficacy of the involvement of different groups, community, and local government, as well as management of the different community agents to give continuity to the health care processes, they are relevant to mitigate problems that affect, to a greater extent, the well-being of people. Besides, they strengthen actions to manage the health system.

11.
Preprint in English | bioRxiv | ID: ppbiorxiv-319863

ABSTRACT

Enveloped viruses, including influenza A viruses (IAVs) and coronaviruses (CoVs), utilize the host cell secretory pathway to synthesize viral glycoproteins and direct them to sites of assembly. Using an image-based high-content screen, we identified two thiopurines, 6-thioguanine (6-TG) and 6-thioguanosine (6-TGo), that selectively disrupted the processing and accumulation of IAV glycoproteins hemagglutinin (HA) and neuraminidase (NA). Selective disruption of IAV glycoprotein processing and accumulation by 6-TG and 6-TGo correlated with unfolded protein response (UPR) activation and HA accumulation could be partially restored by the chemical chaperone 4-phenylbutyrate (4PBA). Chemical inhibition of the integrated stress response (ISR) restored accumulation of NA monomers in the presence of 6-TG or 6-TGo, but did not restore NA glycosylation or oligomerization. Thiopurines inhibited replication of the human coronavirus OC43 (HCoV-OC43), which also correlated with UPR/ISR activation and diminished accumulation of ORF1ab and nucleocapsid (N) mRNAs and N protein, which suggests broader disruption of coronavirus gene expression in ER-derived cytoplasmic compartments. The chemically similar thiopurine 6-mercaptopurine (6-MP) had little effect on the UPR and did not affect IAV or HCoV-OC43 replication. Consistent with reports on other CoV Spike (S) proteins, ectopic expression of SARS-CoV-2 S protein caused UPR activation. 6-TG treatment inhibited accumulation of full length S0 or furin-cleaved S2 fusion proteins, but spared the S1 ectodomain. DBeQ, which inhibits the p97 AAA-ATPase required for retrotranslocation of ubiquitinated misfolded proteins during ER-associated degradation (ERAD) restored accumulation of S0 and S2 proteins in the presence of 6-TG, suggesting that 6-TG induced UPR accelerates ERAD-mediated turnover of membrane-anchored S0 and S2 glycoproteins. Taken together, these data indicate that 6-TG and 6-TGo are effective host-targeted antivirals that trigger the UPR and disrupt accumulation of viral glycoproteins. Importantly, our data demonstrate for the first time the efficacy of these thiopurines in limiting IAV and HCoV-OC43 replication in cell culture models. IMPORTANCESecreted and transmembrane proteins are synthesized in the endoplasmic reticulum (ER), where they are folded and modified prior to transport. During infection, many viruses burden the ER with the task of creating and processing viral glycoproteins that will ultimately be incorporated into viral envelopes. Some viruses refashion the ER into replication compartments where viral gene expression and genome replication take place. This viral burden on the ER can trigger the cellular unfolded protein response (UPR), which attempts to increase the protein folding and processing capacity of the ER to match the protein load. Much remains to be learned about how viruses co-opt the UPR to ensure efficient synthesis of viral glycoproteins. Here, we show that two FDA-approved thiopurine drugs, 6-TG and 6-TGo, induce the UPR in a manner that impedes viral glycoprotein accumulation for enveloped influenza viruses and coronaviruses. These drugs may impede the replication of viruses that require precise tuning of the UPR to support viral glycoprotein synthesis for the successful completion of a replication cycle.

12.
J Cell Sci ; 133(20)2020 10 28.
Article in English | MEDLINE | ID: mdl-32989041

ABSTRACT

Translation arrest is a part of the cellular stress response that decreases energy consumption and enables rapid reprioritisation of gene expression. Often translation arrest leads to condensation of untranslated messenger ribonucleoproteins (mRNPs) into stress granules (SGs). Studies into mechanisms of SG formation and functions are complicated because various types of stress cause formation of SGs with different properties and composition. In this work, we focused on the mechanism of SG formation triggered by UV damage. We demonstrate that UV-induced inhibition of translation does not involve inhibition of the mechanistic target of rapamycin (mTOR) signaling or dissociation of the 48S preinitiation complexes. The general control non-derepressible 2 (GCN2; also known as EIF2AK4) kinase contributes to UV-induced SG formation, which is independent of the phosphorylation of the eukaryotic translation initiation factor 2α. Like many other types of SGs, condensation of UV-induced granules requires the Ras-GTPase-activating protein SH3-domain-binding protein 1 (G3BP1). Our work reveals that, in UV-treated cells, the mechanisms of translation arrest and SG formation may be unlinked, resulting in SGs that do not contain the major type of polysome-free preinitiation complexes that accumulate in the cytoplasm.This article has an associated First Person interview with the first author of the paper.


Subject(s)
DNA Helicases , RNA Helicases , Carrier Proteins , Cytoplasmic Granules , Poly-ADP-Ribose Binding Proteins , RNA Helicases/genetics , RNA Recognition Motif Proteins , TOR Serine-Threonine Kinases/genetics
13.
Diagn Interv Imaging ; 101(6): 347-353, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32360351

ABSTRACT

The COVID-19 pandemic has deeply impacted the activity of interventional oncology in hospitals and cancer centers. In this review based on official recommendations of different international societies, but also on local solutions found in different expert large-volume centers, we discuss the changes that need to be done for the organization, safety, and patient management in interventional oncology. A literature review of potential solutions in a context of scarce anesthesiologic resources, limited staff and limited access to hospital beds are proposed and discussed based on the literature data.


Subject(s)
Betacoronavirus , Cancer Care Facilities/organization & administration , Coronavirus Infections/epidemiology , Neoplasms/therapy , Pandemics , Pneumonia, Viral/epidemiology , Aerosols , Age Factors , Anesthesia, General , Anesthesiology/statistics & numerical data , Biopsy/adverse effects , Biopsy/methods , COVID-19 , COVID-19 Testing , Carcinoma, Hepatocellular/therapy , Carcinoma, Renal Cell/therapy , Chemoembolization, Therapeutic/methods , Clinical Laboratory Techniques/methods , Colonic Neoplasms/pathology , Coronavirus Infections/complications , Coronavirus Infections/diagnosis , Coronavirus Infections/transmission , Databases, Factual , Health Personnel/statistics & numerical data , Health Resources/organization & administration , Health Resources/supply & distribution , Hospital Bed Capacity/statistics & numerical data , Hospitalization/statistics & numerical data , Humans , Hyperthermia, Induced/methods , Kidney Neoplasms/therapy , Liver Neoplasms/therapy , Lung Neoplasms/secondary , Lung Neoplasms/therapy , Neoplasms/complications , Palliative Care/methods , Pneumonia, Viral/complications , Pneumonia, Viral/diagnosis , Pneumonia, Viral/transmission , SARS-CoV-2 , Triage
14.
J Virol ; 94(13)2020 06 16.
Article in English | MEDLINE | ID: mdl-32321802

ABSTRACT

Influenza A virus (IAV) increases the presentation of class I human leukocyte antigen (HLA) proteins that limit antiviral responses mediated by natural killer (NK) cells, but molecular mechanisms for these processes have not yet been fully elucidated. We observed that infection with A/Fort Monmouth/1/1947(H1N1) IAV significantly increased the presentation of HLA-B, -C, and -E on lung epithelial cells. Virus entry was not sufficient to induce HLA upregulation because UV-inactivated virus had no effect. Aberrant internally deleted viral RNAs (vRNAs) known as mini viral RNAs (mvRNAs) and defective interfering RNAs (DI RNAs) expressed from an IAV minireplicon were sufficient for inducing HLA upregulation. These defective RNAs bind to retinoic acid-inducible gene I (RIG-I) and initiate mitochondrial antiviral signaling (MAVS) protein-dependent antiviral interferon (IFN) responses. Indeed, MAVS was required for HLA upregulation in response to IAV infection or ectopic mvRNA/DI RNA expression. The effect was partially due to paracrine signaling, as we observed that IAV infection or mvRNA/DI RNA-expression stimulated production of IFN-ß and IFN-λ1 and conditioned media from these cells elicited a modest increase in HLA surface levels in naive epithelial cells. HLA upregulation in response to aberrant viral RNAs could be prevented by the Janus kinase (JAK) inhibitor ruxolitinib. While HLA upregulation would seem to be advantageous to the virus, it is kept in check by the viral nonstructural 1 (NS1) protein; we determined that NS1 limits cell-intrinsic and paracrine mechanisms of HLA upregulation. Taken together, our findings indicate that aberrant IAV RNAs stimulate HLA presentation, which may aid viral evasion of innate immunity.IMPORTANCE Human leukocyte antigens (HLAs) are cell surface proteins that regulate innate and adaptive immune responses to viral infection by engaging with receptors on immune cells. Many viruses have evolved ways to evade host immune responses by modulating HLA expression and/or processing. Here, we provide evidence that aberrant RNA products of influenza virus genome replication can trigger retinoic acid-inducible gene I (RIG-I)/mitochondrial antiviral signaling (MAVS)-dependent remodeling of the cell surface, increasing surface presentation of HLA proteins known to inhibit the activation of an immune cell known as a natural killer (NK) cell. While this HLA upregulation would seem to be advantageous to the virus, it is kept in check by the viral nonstructural 1 (NS1) protein, which limits RIG-I activation and interferon production by the infected cell.


Subject(s)
Genes, MHC Class I/genetics , HLA Antigens/metabolism , Influenza A Virus, H1N1 Subtype/genetics , A549 Cells , Adaptor Proteins, Signal Transducing/genetics , DEAD Box Protein 58/genetics , Databases, Genetic , Epithelial Cells/virology , Host-Pathogen Interactions/genetics , Humans , Immunity, Innate , Influenza A virus/genetics , Influenza, Human/genetics , Killer Cells, Natural/metabolism , Lung/virology , RNA, Viral/genetics , Signal Transduction , Transcriptional Activation , Viral Nonstructural Proteins/metabolism , Virus Replication/genetics
16.
Rev Salud Publica (Bogota) ; 22(6): 571-574, 2020 11 01.
Article in Spanish | MEDLINE | ID: mdl-36753073

ABSTRACT

As main feature, the global health crisis due to COVID-19 affects the most vulnerable groups of people. The main way of contagion of this disease is the airway transmission by social contact. Countries take steps to reduce the consequences of the pandemic and significantly improve the well-being of the people. However, they must boost measurements to support the capacity to resolve situations at the first level of assistance, mainly for the people that are so vulnerable: persons with disabilities, that get everyday worse. The Community Based Rehabilitation has been a strategy that group together collective and individual factors. The effectiveness and efficacy of the involvement of different groups, community, and local government, as well as management of the different community agents to give continuity to the health care processes, they are relevant to mitigate problems that affect, to a greater extent, the well-being of people. Besides, they strengthen actions to manage the health system.


La crisis sanitaria mundial que enfrenta el mundo debido al COVID-19 tiene como característica principal que afecta la población más vulnerable. La principal vía de contagio de esta enfermedad es la transmisión aérea debido al contacto social. Los países adoptaron una serie de intervenciones focalizadas para mitigar las consecuencias derivadas de esta pandemia e impactar significativamente en el bienestar de las personas. No obstante, se deben fortalecer acciones que favorezcan la capacidad resolutiva en el primer nivel de atención, especialmente, en poblaciones de alta vulnerabilidad, entre ellas, las personas en situación de discapacidad, cuyas circunstancias tienden a complicarse. La rehabilitación basada en comunidad ha sido una estrategia de gran impacto social que integra una serie de factores tanto individuales como colectivos. La eficacia y efectividad de la participación intersectorial, comunitaria y de los Gobiernos locales, así como la gestión de los diferentes agentes comunitarios para darle continuidad a los procesos de atención en salud son pertinentes para amortiguar situaciones de alta complejidad que alteran, en mayor medida, el bienestar de todas las personas. Además, contribuyen a potencializar acciones para gestionar el sistema de salud.


Subject(s)
COVID-19 , Disabled Persons , Humans , Disabled Persons/rehabilitation , Global Health
17.
Br J Oral Maxillofac Surg ; 58(1): 75-78, 2020 01.
Article in English | MEDLINE | ID: mdl-31735400

ABSTRACT

Treatment of bony tumours of the oral and maxillofacial area usually involve resection. However, access to certain areas may be difficult because of the size or site of the tumour. A poor view of the lesion during operation is another limiting factor, which can lead to incomplete resection in difficult cases. Percutaneous cryoablation is a common procedure for treating benign and malignant bony lesions outside the oral and maxillofacial area, but has to our knowledge never been used as a stand-alone treatment as we describe here. In 2016, three patients with benign bony tumours of the mandible (one a keratocyst, one an angiofibroma, and one a giant cell granuloma) were treated with one session of percutaneous cryoablation. Outcomes were monitored with computed tomography or magnetic resonance imaging at one year. No patient had a procedure-related complication, and there were no other complications. Radiological controls showed complete recovery. Percutaneous cryoablation seems to be an interesting and valuable alternative to resection for bony lesions with its limited access and high operative morbidity.


Subject(s)
Bone Neoplasms , Soft Tissue Neoplasms , Cryosurgery , Humans , Mandible , Treatment Outcome
19.
Cell Rep ; 27(3): 776-792.e7, 2019 04 16.
Article in English | MEDLINE | ID: mdl-30995476

ABSTRACT

Many viruses shut off host gene expression to inhibit antiviral responses. Viral proteins and host proteins required for viral replication are typically spared in this process, but the mechanisms of target selectivity during host shutoff remain poorly understood. Using transcriptome-wide and targeted reporter experiments, we demonstrate that the influenza A virus endoribonuclease PA-X usurps RNA splicing to selectively target host RNAs for destruction. Proximity-labeling proteomics reveals that PA-X interacts with cellular RNA processing proteins, some of which are partially required for host shutoff. Thus, PA-X taps into host nuclear pre-mRNA processing mechanisms to destroy nascent mRNAs shortly after their synthesis. This mechanism sets PA-X apart from other viral host shutoff proteins that target actively translating mRNAs in the cytoplasm. Our study reveals a unique mechanism of host shutoff that helps us understand how influenza viruses suppress host gene expression.


Subject(s)
Influenza A virus/physiology , RNA Splicing , RNA, Messenger/metabolism , Repressor Proteins/metabolism , Viral Nonstructural Proteins/metabolism , A549 Cells , Cleavage And Polyadenylation Specificity Factor/antagonists & inhibitors , Cleavage And Polyadenylation Specificity Factor/genetics , Cleavage And Polyadenylation Specificity Factor/metabolism , Down-Regulation , Endoribonucleases/metabolism , HEK293 Cells , Host-Pathogen Interactions , Humans , Interferons/genetics , Interferons/metabolism , Mutagenesis, Site-Directed , RNA Interference , RNA Precursors/metabolism , RNA Splice Sites , RNA, Small Interfering/metabolism , Repressor Proteins/genetics , Up-Regulation , Viral Nonstructural Proteins/genetics , mRNA Cleavage and Polyadenylation Factors/antagonists & inhibitors , mRNA Cleavage and Polyadenylation Factors/genetics , mRNA Cleavage and Polyadenylation Factors/metabolism
20.
Diagn Interv Imaging ; 100(3): 147-156, 2019 03.
Article in English | MEDLINE | ID: mdl-30503174

ABSTRACT

PURPOSE: The purpose of this study was to evaluate the feasibility, safety, and efficacy of portal vein recanalization (PVR) and propose a new classification for better selecting candidates with portal vein occlusion (PVO) in whom PVR could be feasible. MATERIALS AND METHODS: The charts of 15 non-cirrhotic patients in whom stent placement using a trans-hepatic approach was attempted for the treatment of PVO with cavernous transformation were reviewed. There were 12 men and 3 women with a mean age of 47 ± 12 years (range: 22­60 years) [corrected]. Intrahepatic involvement was classified into 3 groups according to the intrahepatic extent of PVO: type 1 included occlusions limited to the origin of the main portal vein and/or the right or left portal branches, type 2 included type 1 plus extension to the origin of segmental branches, type 3 included type 2 plus extension to distal branches. RESULTS: There were 6 patients with PVO type 1, 7 patients with PVO type 2, and 2 patients with PVO type 3. Indications for PVR were gastrointestinal bleeding (n=6), portal biliopathy (n=2), reduce portal pressure before surgery (n=4), or other (n=3). PVR was successful in 13 patients (87%) with no severe side effects. Failure of PVR or early stent thrombosis occurred in 100% of type 3 vs. 8% of type 1 and 2 patients (P=0.03). During a mean follow-up of 42±28 months (range: 6-112 months), patients with a permeable stent had resolution of portal hypertension-related manifestations. In 13 patients in whom PVR was feasible, stent permeability was 77% at 2 years (87% vs. 60% in patients who received anticoagulation or not, respectively; P=0.3). CONCLUSION: PVR is feasible in most patients with non-cirrhotic, non-tumoral portal vein occlusion when there is no extension of the occlusion to distal branches.


Subject(s)
Alloys , Hypertension, Portal/therapy , Portal Vein/abnormalities , Stents , Venous Thrombosis/therapy , Adult , Feasibility Studies , Female , Follow-Up Studies , Humans , Hypertension, Portal/diagnostic imaging , Liver Function Tests , Male , Middle Aged , Phlebography , Portal Vein/diagnostic imaging , Venous Thrombosis/diagnostic imaging , Young Adult
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