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1.
Cell ; 182(3): 685-712.e19, 2020 08 06.
Article in English | MEDLINE | ID: mdl-32645325

ABSTRACT

The causative agent of the coronavirus disease 2019 (COVID-19) pandemic, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected millions and killed hundreds of thousands of people worldwide, highlighting an urgent need to develop antiviral therapies. Here we present a quantitative mass spectrometry-based phosphoproteomics survey of SARS-CoV-2 infection in Vero E6 cells, revealing dramatic rewiring of phosphorylation on host and viral proteins. SARS-CoV-2 infection promoted casein kinase II (CK2) and p38 MAPK activation, production of diverse cytokines, and shutdown of mitotic kinases, resulting in cell cycle arrest. Infection also stimulated a marked induction of CK2-containing filopodial protrusions possessing budding viral particles. Eighty-seven drugs and compounds were identified by mapping global phosphorylation profiles to dysregulated kinases and pathways. We found pharmacologic inhibition of the p38, CK2, CDK, AXL, and PIKFYVE kinases to possess antiviral efficacy, representing potential COVID-19 therapies.


Subject(s)
Betacoronavirus/metabolism , Coronavirus Infections/metabolism , Drug Evaluation, Preclinical/methods , Pneumonia, Viral/metabolism , Proteomics/methods , A549 Cells , Angiotensin-Converting Enzyme 2 , Animals , Antiviral Agents/pharmacology , COVID-19 , Caco-2 Cells , Casein Kinase II/antagonists & inhibitors , Casein Kinase II/metabolism , Chlorocebus aethiops , Coronavirus Infections/virology , Cyclin-Dependent Kinases/antagonists & inhibitors , Cyclin-Dependent Kinases/metabolism , HEK293 Cells , Host-Pathogen Interactions , Humans , Pandemics , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Phosphoinositide-3 Kinase Inhibitors/pharmacology , Phosphorylation , Pneumonia, Viral/virology , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins/antagonists & inhibitors , Proto-Oncogene Proteins/metabolism , Receptor Protein-Tyrosine Kinases/antagonists & inhibitors , Receptor Protein-Tyrosine Kinases/metabolism , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/metabolism , Vero Cells , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors , p38 Mitogen-Activated Protein Kinases/metabolism , Axl Receptor Tyrosine Kinase
2.
Nature ; 583(7816): 459-468, 2020 07.
Article in English | MEDLINE | ID: mdl-32353859

ABSTRACT

A newly described coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is the causative agent of coronavirus disease 2019 (COVID-19), has infected over 2.3 million people, led to the death of more than 160,000 individuals and caused worldwide social and economic disruption1,2. There are no antiviral drugs with proven clinical efficacy for the treatment of COVID-19, nor are there any vaccines that prevent infection with SARS-CoV-2, and efforts to develop drugs and vaccines are hampered by the limited knowledge of the molecular details of how SARS-CoV-2 infects cells. Here we cloned, tagged and expressed 26 of the 29 SARS-CoV-2 proteins in human cells and identified the human proteins that physically associated with each of the SARS-CoV-2 proteins using affinity-purification mass spectrometry, identifying 332 high-confidence protein-protein interactions between SARS-CoV-2 and human proteins. Among these, we identify 66 druggable human proteins or host factors targeted by 69 compounds (of which, 29 drugs are approved by the US Food and Drug Administration, 12 are in clinical trials and 28 are preclinical compounds). We screened a subset of these in multiple viral assays and found two sets of pharmacological agents that displayed antiviral activity: inhibitors of mRNA translation and predicted regulators of the sigma-1 and sigma-2 receptors. Further studies of these host-factor-targeting agents, including their combination with drugs that directly target viral enzymes, could lead to a therapeutic regimen to treat COVID-19.


Subject(s)
Betacoronavirus/drug effects , Coronavirus Infections/drug therapy , Coronavirus Infections/metabolism , Drug Repositioning , Molecular Targeted Therapy , Pneumonia, Viral/drug therapy , Pneumonia, Viral/metabolism , Protein Interaction Maps , Viral Proteins/metabolism , Animals , Antiviral Agents/classification , Antiviral Agents/pharmacology , Betacoronavirus/genetics , Betacoronavirus/metabolism , Betacoronavirus/pathogenicity , COVID-19 , Chlorocebus aethiops , Cloning, Molecular , Coronavirus Infections/immunology , Coronavirus Infections/virology , Drug Evaluation, Preclinical , HEK293 Cells , Host-Pathogen Interactions/drug effects , Humans , Immunity, Innate , Mass Spectrometry , Pandemics , Pneumonia, Viral/immunology , Pneumonia, Viral/virology , Protein Binding , Protein Biosynthesis/drug effects , Protein Domains , Protein Interaction Mapping , Receptors, sigma/metabolism , SARS-CoV-2 , SKP Cullin F-Box Protein Ligases/metabolism , Vero Cells , Viral Proteins/genetics , COVID-19 Drug Treatment
3.
Curr Opin Infect Dis ; 37(1): 17-25, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-37889583

ABSTRACT

PURPOSE OF REVIEW: Early detection and treatment of human papillomavirus (HPV)-related anal dysplasia in some high-risk groups can help anal cancer prevention, but new tools to improve diagnostic and risk assessment are needed. Here, we aim to discuss the evidence on the role of the microbiome as a potential biomarker for anal high-grade squamous intraepithelial lesions (HSILs) in people with HIV (PWH). RECENT FINDINGS: This review covers relevant studies on the links between the microbiome and HPV infection, cervical dysplasia/cancer, and anal HPV disease. It focuses on anal samples and precancerous lesions. SUMMARY: The review highlights the promising potential of the anal microbiome as a novel biomarker for precancerous lesions in people with HIV, while also discussing limitations and future research needs.


Subject(s)
Anus Neoplasms , HIV Infections , Papillomavirus Infections , Precancerous Conditions , Female , Humans , Papillomavirus Infections/complications , Papillomavirus Infections/diagnosis , Precancerous Conditions/diagnosis , Anus Neoplasms/diagnosis , Biomarkers , HIV Infections/complications
4.
Clin Proteomics ; 21(1): 37, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38778280

ABSTRACT

BACKGROUND: Information on the microbiome's human pathways and active members that can affect SARS-CoV-2 susceptibility and pathogenesis in the salivary proteome is very scarce. Here, we studied a unique collection of samples harvested from April to June 2020 from unvaccinated patients. METHODS: We compared 10 infected and hospitalized patients with severe (n = 5) and moderate (n = 5) coronavirus disease (COVID-19) with 10 uninfected individuals, including non-COVID-19 but susceptible individuals (n = 5) and non-COVID-19 and nonsusceptible healthcare workers with repeated high-risk exposures (n = 5). RESULTS: By performing high-throughput proteomic profiling in saliva samples, we detected 226 unique differentially expressed (DE) human proteins between groups (q-value ≤ 0.05) out of 3376 unambiguously identified proteins (false discovery rate ≤ 1%). Major differences were observed between the non-COVID-19 and nonsusceptible groups. Bioinformatics analysis of DE proteins revealed human proteomic signatures related to inflammatory responses, central cellular processes, and antiviral activity associated with the saliva of SARS-CoV-2-infected patients (p-value ≤ 0.0004). Discriminatory biomarker signatures from human saliva include cystatins, protective molecules present in the oral cavity, calprotectins, involved in cell cycle progression, and histones, related to nucleosome functions. The expression levels of two human proteins related to protein transport in the cytoplasm, DYNC1 (p-value, 0.0021) and MAPRE1 (p-value, 0.047), correlated with angiotensin-converting enzyme 2 (ACE2) plasma activity. Finally, the proteomes of microorganisms present in the saliva samples showed 4 main microbial functional features related to ribosome functioning that were overrepresented in the infected group. CONCLUSION: Our study explores potential candidates involved in pathways implicated in SARS-CoV-2 susceptibility, although further studies in larger cohorts will be necessary.

5.
Eat Disord ; 32(1): 29-42, 2024 Jan 02.
Article in English | MEDLINE | ID: mdl-37599453

ABSTRACT

This study aimed to analyze body size estimates of others by patients with anorexia nervosa (AN) and to identify any differences with the perception of their own body size. Adolescent females (age, 13-17 years) were enrolled into AN (n = 30) and control(n = 23) groups. The Subjective Body Dimensions Apparatus (SBDA) was used to evaluate body size estimates for oneself (self-estimation) and others (other-estimation). Participants also completed questionnaires assessing eating disorders and depressive symptoms. The AN and control groups scored significantly higher in self-estimation than in other-estimation. However, the AN group showed higher self-estimation scores than the control group for all the body parts and for the global silhouette (p < .001). Patients with more severe eating disorder symptomatology showed more distorted self-estimation (p < .05). No statistically significant differences were found in the other-estimation scores between the groups (p = .714), indicating that AN and control patients estimate the body sizes of others similarly. Eating disorder symptomatology correlates with self-estimation scores but not with other-estimation scores in adolescents with AN. No correlations existed between clinical symptomatology and other-estimation.


Subject(s)
Anorexia Nervosa , Feeding and Eating Disorders , Female , Humans , Adolescent , Anorexia Nervosa/diagnosis , Body Image , Body Size
6.
J Sport Rehabil ; 33(3): 155-160, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38253048

ABSTRACT

CONTEXT: Suspension training devices are becoming increasingly popular. Most studies analyzed the effectiveness according to diverse measures in patients with or without conditions at any age. The characteristics of suspension training are very specific and can increase instability and; therefore, enhance balance. The goal was to determine the effects of suspension training on balance by comparing it with instability training. DESIGN: Two-arm, randomized trial. METHODS: 44 young adults, aged 22.4 years old, with no musculoskeletal condition, took part. There were 2 interventions, suspension and instability training, designed with 12 sessions in 4 weeks. The primary outcome was the Y-Balance test. Other balance outcomes were the Emery and jumping sideways tests, and platform measures while standing. RESULTS: Suspension and instability training were effective in enhancing balance in terms of the primary outcome, the Y-Balance test, with no between-group differences. Instability training enhanced the Emery test over suspension training (P = .018), but the latter was more effective in the jumping sideways test (P = .003). Neither of the training improved static balance measures. CONCLUSIONS: Training with suspension devices is effective in enhancing dynamic balance, with similar improvements to instability training. Importantly, the magnitude of change and the frequency of responders to intervention in terms of motor coordination and keeping balance in unstable conditions appear to be sensitive to the type of training.


Subject(s)
Musculoskeletal Diseases , Young Adult , Humans , Adult , Standing Position
7.
Clin Infect Dis ; 76(9): 1688-1696, 2023 05 03.
Article in English | MEDLINE | ID: mdl-36883584

ABSTRACT

In the last decade, studies in persons with HIV (PWH) on antiretroviral therapy (ART) have shed light on the significance of persistently high CD8 counts and low CD4/CD8 ratios. A low CD4/CD8 ratio reflects increased immune activation and is associated with an increased risk of severe non-AIDS events. As a result, many clinicians now believe that the CD4/CD8 ratio can help in HIV monitoring, and many researchers now report it as an efficacy marker in interventional studies. However, the topic is more complex. Recent studies have not yielded unanimous conclusions on the ability of the CD4/CD8 ratio to predict adverse outcomes, and only some clinical guidelines recommend monitoring it. Knowledge gaps remain on the best cutoff points, associated clinical events, effects of treatments, and how the CD4/CD8 ratio could improve decision making in the clinic. Here, we critically review the literature, identify knowledge gaps, and discuss the role of the CD4/CD8 ratio as a marker for HIV monitoring.


Subject(s)
Anti-HIV Agents , HIV Infections , Humans , HIV , Anti-HIV Agents/therapeutic use , CD4-CD8 Ratio , CD8-Positive T-Lymphocytes , CD4 Lymphocyte Count , Viral Load
8.
BMC Genomics ; 24(1): 567, 2023 Sep 23.
Article in English | MEDLINE | ID: mdl-37741970

ABSTRACT

Metabolic-dysfunction-associated fatty liver disease (MAFLD) is a comorbidity that generally increases in people living with HIV (PLWH). This condition is usually accompanied by persistent inflammation and premature immune system aging. In this prospective cohort study, we describe a straightforward methodology for quantifying biomarkers of aging, such as DNA methylation and telomere length, in PLWH and in the context of another relevant condition, such as MAFLD. Fifty-seven samples in total, thirty-eight from PLWH and nineteen from non-PLWH participants with or without MAFLD, were obtained and subjected to DNA extraction from peripheral blood mononuclear cells (PBMCs). Global DNA methylation and telomere length quantification were performed using an adapted enzyme-linked immunosorbent assay (ELISA) and qPCR, respectively. The quantification results were analysed and corrected by clinically relevant variables in this context, such as age, sex, and metabolic syndrome. Our results show an increased association of these biomarkers in PLWH regardless of their MAFLD status. Thus, we propose including the quantification of these age-related factors in studies of comorbidities. This will allow a better understanding of the effect of comorbidities of HIV infection and MAFLD and prevent their effects in these populations in the future.


Subject(s)
Aging, Premature , HIV Infections , Non-alcoholic Fatty Liver Disease , Humans , DNA Methylation , Non-alcoholic Fatty Liver Disease/genetics , HIV Infections/complications , HIV Infections/genetics , Leukocytes, Mononuclear , Prospective Studies , Aging/genetics , Telomere/genetics
9.
Proc Natl Acad Sci U S A ; 117(45): 28344-28354, 2020 11 10.
Article in English | MEDLINE | ID: mdl-33097660

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the ongoing coronavirus disease 2019 (COVID-19) pandemic that is a serious global health problem. Evasion of IFN-mediated antiviral signaling is a common defense strategy that pathogenic viruses use to replicate and propagate in their host. In this study, we show that SARS-CoV-2 is able to efficiently block STAT1 and STAT2 nuclear translocation in order to impair transcriptional induction of IFN-stimulated genes (ISGs). Our results demonstrate that the viral accessory protein Orf6 exerts this anti-IFN activity. We found that SARS-CoV-2 Orf6 localizes at the nuclear pore complex (NPC) and directly interacts with Nup98-Rae1 via its C-terminal domain to impair docking of cargo-receptor (karyopherin/importin) complex and disrupt nuclear import. In addition, we show that a methionine-to-arginine substitution at residue 58 impairs Orf6 binding to the Nup98-Rae1 complex and abolishes its IFN antagonistic function. All together our data unravel a mechanism of viral antagonism in which a virus hijacks the Nup98-Rae1 complex to overcome the antiviral action of IFN.


Subject(s)
COVID-19/metabolism , Interferons/metabolism , Nuclear Pore Complex Proteins/metabolism , Nuclear Pore/metabolism , STAT1 Transcription Factor/metabolism , STAT2 Transcription Factor/metabolism , Viral Proteins/metabolism , Active Transport, Cell Nucleus , Animals , Binding Sites , Chlorocebus aethiops , HEK293 Cells , Humans , Nuclear Matrix-Associated Proteins/chemistry , Nuclear Matrix-Associated Proteins/metabolism , Nucleocytoplasmic Transport Proteins/chemistry , Nucleocytoplasmic Transport Proteins/metabolism , Protein Binding , Signal Transduction , Vero Cells
10.
Eur Child Adolesc Psychiatry ; 32(3): 513-526, 2023 Mar.
Article in English | MEDLINE | ID: mdl-34604924

ABSTRACT

Anorexia nervosa (AN) typically emerges in adolescence. The cortico-striatal system (CSTS) and the default mode network (DMN) are brain circuits with a crucial development during this period. These circuits underlie cognitive functions that are impaired in AN, such as cognitive flexibility and inhibition, among others. Little is known about their involvement in adolescent AN and how weight and symptom improvement might modulate potential alterations in these circuits. Forty-seven adolescent females (30 AN, 17 healthy control) were clinically/neuropsychologically evaluated and scanned during a 3T-MRI resting-state session on two occasions, before and after a 6-month multidisciplinary treatment of the AN patients. Baseline and baseline-to-follow-up between-group differences in CSTS and DMN resting-state connectivity were evaluated, as well as their association with clinical/neuropsychological variables. Increased connectivity between the left dorsal putamen and the left precuneus was found in AN at baseline. At follow-up, body mass index and clinical symptoms had improved in the AN group. An interaction effect was found in the connectivity between the right dorsal caudate to right mid-anterior insular cortex, with lower baseline AN connectivity that improved at follow-up; this improvement was weakly associated with changes in neuropsychological (Stroop test) performance. These results support the presence of CSTS connectivity alterations in adolescents with AN, which improve with weight and symptom improvement. In addition, at the level of caudate-insula connectivity, they might be associated with inhibitory processing performance. Alterations in CSTS pathways might be involved in AN from the early stages of the disorder.


Subject(s)
Anorexia Nervosa , Brain Mapping , Female , Humans , Adolescent , Longitudinal Studies , Anorexia Nervosa/diagnostic imaging , Anorexia Nervosa/therapy , Default Mode Network , Neural Pathways/diagnostic imaging , Brain/diagnostic imaging , Magnetic Resonance Imaging/methods
11.
Salud Publica Mex ; 66(1, ene-feb): 104-112, 2023 Dec 08.
Article in Spanish | MEDLINE | ID: mdl-38065103

ABSTRACT

The growing cancer burden particularly among less developed countries requires local data to plan and evaluate cancer control measures. This article describes the development of a population-based cancer registry network (PBCRN) in Mexico that took place between 2017 and 2020 and present related data. The PBCRN, led by the National Cancer Institute (Incan), included nine registries representing 11.3% of the Mexican population. Definitions, coding, and operative processes were based on international standards. All cities were visited to set up local structure; personnel were hired by Incan and trained in basic cancer registration in Merida. A specific software was developed. Regular virtual meetings took place for data verification and quality control. Data collection included institutions of the public and private health system. Personnel included 34 registrars, nine local leaders, and 12 staff members at the Incan. A total of 13 517 cases were recorded between 2017-2020, 64% percent of them were among females. Breast cancer was the more frequent malignancy (23.3%), followed by digestive organs with (18.4%) and female genital cancers (13.5%). Childhood (0-14 years) and adolescents cancer represented 4.4% of the total new cancer cases. The network was suspended in 2020. The present effort lacked sustainability and data were only partial. However, the experience provides valuable insights to be considered for the renewed cancer registration efforts that are currently ongoing in Mexico.

12.
Medicina (Kaunas) ; 60(1)2023 Dec 26.
Article in English | MEDLINE | ID: mdl-38256308

ABSTRACT

Background and Objectives: While suspension training devices are increasingly gaining popularity, there is limited evidence on their effects on balance, and no comprehensive assessment has been conducted. This study aimed to evaluate the effects of a 9-session suspension training program on dynamic and static balance, stability, and functional performance. Materials and Methods: A total of forty-eight healthy adults, aged between 18 and 30, participated in a 9-session suspension training program. The program included exercises targeting upper and lower body muscles as well as core muscles. Balance was comprehensively assessed using various dynamic balance tests, including the Y Balance Test (YBT) as the primary outcome, single-leg Emery test, and sideways jumping test. Static balance was evaluated through the monopedal and bipedal Romberg tests. Changes from baseline were analyzed using a one-way ANOVA test. Results: Thirty-nine participants (mean age: 21.8 years) completed the intervention. The intervention resulted in significant improvements in YBT, jumping sideways, Emery, and 30s-SST scores (p < 0.001). Platform measures indicated enhanced monopedal stability (p < 0.001) but did not show a significant effect on bipedal stability (p > 0.05). Conclusions: Suspension training is a safe and feasible method for improving dynamic balance and functional performance in healthy, untrained young adults. However, it does not appear to significantly impact the ability to maintain a static posture while standing.


Subject(s)
Exercise , Research , Young Adult , Humans , Adolescent , Adult , Analysis of Variance , Exercise Therapy , Health Status , Suspensions
13.
J Proteome Res ; 21(3): 623-634, 2022 03 04.
Article in English | MEDLINE | ID: mdl-35133846

ABSTRACT

Despite the scientific and human efforts to understand COVID-19, there are questions still unanswered. Variations in the metabolic reaction to SARS-CoV-2 infection could explain the striking differences in the susceptibility to infection and the risk of severe disease. Here, we used untargeted metabolomics to examine novel metabolic pathways related to SARS-CoV-2 susceptibility and COVID-19 clinical severity using capillary electrophoresis coupled to a time-of-flight mass spectrometer (CE-TOF-MS) in plasma samples. We included 27 patients with confirmed COVID-19 and 29 healthcare workers heavily exposed to SARS-CoV-2 but with low susceptibility to infection ("nonsusceptible"). We found a total of 42 metabolites of SARS-CoV-2 susceptibility or COVID-19 clinical severity. We report the discovery of new plasma biomarkers for COVID-19 that provide mechanistic explanations for the clinical consequences of SARS-CoV-2, including mitochondrial and liver dysfunction as a consequence of hypoxemia (citrulline, citric acid, and 3-aminoisobutyric acid (BAIBA)), energy production and amino acid catabolism (phenylalanine and histidine), and endothelial dysfunction and thrombosis (citrulline, asymmetric dimethylarginine (ADMA), and 2-aminobutyric acid (2-AB)), and we found interconnections between these pathways. In summary, in this first report several metabolic pathways implicated in SARS-CoV-2 susceptibility and COVID-19 clinical progression were found by CE-MS based metabolomics that could be developed as biomarkers of COVID-19.


Subject(s)
COVID-19 , SARS-CoV-2 , Biomarkers , Humans , Metabolome , Metabolomics/methods
14.
Rev Panam Salud Publica ; 46: e144, 2022.
Article in English | MEDLINE | ID: mdl-36128473

ABSTRACT

Objective: In 2021, Mexico launched the HEARTS program to improve the prevention and control of cardiovascular disease (CVD) risk factors in 20 primary care facilities in the states of Chiapas and Yucatán. This study projects the annual cost of program implementation and discusses budgetary implications for scaling up the program. Methods: We obtained district-level data on treatment protocols, medication costs, and other resources required to prevent and treat CVD. We used the HEARTS Costing Tool to estimate total and per-patient costs. A "partial implementation" scenario calculated the costs of implementing HEARTS if existing pharmacological treatment protocols are left in place. The second scenario, "full implementation," examined costs if programs use HEARTS pharmacological protocol. Results: Respectively in the partial and full implementation scenarios, total annual costs to implement and operate HEARTS were $260 023 ($32.1 per patient/year) and $255 046 ($31.5 per patient/year) in Chiapas, and $1 000 059 ($41.3 per patient/year) and $1 013 835 ($43.3 per patient/year) in Yucatán. In Chiapas, adopting HEARTS standardized treatment protocols resulted in a 9.7 % reduction in annual medication expenditures relative to maintaining status-quo treatment approaches. In Yucatán, adoption was $12 875 more expensive, in part because HEARTS hypertension treatment regimens were more intensive than status quo regimens. Conclusion: HEARTS in the Americas offers a standardized strategy to treating and controlling CVD risk factors. In Mexico, approaches that may lead to improved program affordability include adoption of the recommended HEARTS treatment protocols with preferred medications and task shifting of services from physicians to nurses and other providers.

15.
Article in English | MEDLINE | ID: mdl-35759074

ABSTRACT

The Child Obsessive-Compulsive Impact Scale (COIS-R) is a parent- and self-report measure of the impairment related to Obsessive-Compulsive Disorder (OCD) symptoms. Previous research has demonstrated the reliability and validity of the original version of the COIS-R; to date, however, the scale has not been validated for use in Spanish samples of pediatric OCD. The present study aimed to assess the psychometric properties of this in a clinical sample of pediatric OCD (n = 91). Analyses of internal consistency, convergent and divergent validity were conducted. For both the COIS-R report scales estimates similar to those in the original instrument were obtained for internal consistency, test-retest reliability, and convergent validity. Thus, the Spanish version of the COIS-R seems to retain sound psychometric properties of its original version; it appears to be a reliable instrument for the assessment of obsessive-compulsive impairment and the effects of treatment, and can be used in other cultural contexts.

16.
Antimicrob Agents Chemother ; 63(12)2019 09 09.
Article in English | MEDLINE | ID: mdl-31570400

ABSTRACT

Lethal mutagenesis is an antiviral approach that consists in extinguishing a virus by an excess of mutations acquired during replication in the presence of a mutagenic agent, often a nucleotide analogue. One of its advantages is its broad spectrum nature that renders the strategy potentially effective against emergent RNA viral infections. Here we describe synergistic lethal mutagenesis of hepatitis C virus (HCV) by a combination of favipiravir (T-705) and ribavirin. Synergy has been documented over a broad range of analogue concentrations using the Chou-Talalay method as implemented in the CompuSyn graphics, with average dose reduction index (DRI) above 1 (68.02±101.6 for favipiravir, and 5.83±6.07 for ribavirin), and average combination indices (CI) below 1 (0.52±0.28). Furthermore, analogue concentrations that individually did not extinguish high fitness HCV in ten serial infections, when used in combination they extinguished high fitness HCV in one to two passages. Although both analogues display a preference for G→A and C→U transitions, deep sequencing analysis of mutant spectra indicated a different preference of the two analogues for the mutation sites, thus unveiling a new possible synergy mechanism in lethal mutagenesis. Prospects of synergy among mutagenic nucleotides as a strategy to confront emerging viral infections are discussed.

17.
J Virol ; 92(20)2018 10 15.
Article in English | MEDLINE | ID: mdl-30068642

ABSTRACT

Viral RNA-dependent RNA polymerases (RdRps) are major determinants of high mutation rates and generation of mutant spectra that mediate RNA virus adaptability. The RdRp of the picornavirus foot-and-mouth disease virus (FMDV), termed 3D, is a multifunctional protein that includes a nuclear localization signal (NLS) in its N-terminal region. Previous studies documented that some amino acid substitutions within the NLS altered nucleotide recognition and enhanced the incorporation of the mutagenic purine analogue ribavirin in viral RNA, but the mutants tested were not viable and their response to lethal mutagenesis could not be studied. Here we demonstrate that NLS amino acid substitution M16A of FMDV serotype C does not affect infectious virus production but accelerates ribavirin-mediated virus extinction. The mutant 3D displays polymerase activity, RNA binding, and copying processivity that are similar to those of the wild-type enzyme but shows increased ribavirin-triphosphate incorporation. Crystal structures of the mutant 3D in the apo and RNA-bound forms reveal an expansion of the template entry channel due to the replacement of the bulky Met by Ala. This is a major difference with other 3D mutants with altered nucleotide analogue recognition. Remarkably, two distinct loop ß9-α11 conformations distinguish 3Ds that exhibit higher or lower ribavirin incorporation than the wild-type enzyme. This difference identifies a specific molecular determinant of ribavirin sensitivity of FMDV. Comparison of several polymerase mutants indicates that different domains of the molecule can modify nucleotide recognition and response to lethal mutagenesis. The connection of this observation with current views on quasispecies adaptability is discussed.IMPORTANCE The nuclear localization signal (NLS) of the foot-and-mouth disease virus (FMDV) polymerase includes residues that modulate the sensitivity to mutagenic agents. Here we have described a viable NLS mutant with an amino acid replacement that facilitates virus extinction by ribavirin. The corresponding polymerase shows increased incorporation of ribavirin triphosphate and local structural modifications that implicate the template entry channel. Specifically, comparison of the structures of ribavirin-sensitive and ribavirin-resistant FMDV polymerases has identified loop ß9-α11 conformation as a determinant of sensitivity to ribavirin mutagenesis.


Subject(s)
Foot-and-Mouth Disease Virus/enzymology , Mutagenesis , RNA-Dependent RNA Polymerase/metabolism , Amino Acid Substitution , Animals , Antiviral Agents/metabolism , Cell Line , Cricetinae , Crystallography, X-Ray , Nuclear Localization Signals , RNA, Viral/biosynthesis , RNA-Dependent RNA Polymerase/chemistry , RNA-Dependent RNA Polymerase/genetics , Ribavirin/metabolism
18.
J Obstet Gynaecol ; 39(1): 98-104, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30207503

ABSTRACT

The objective of our study was to determine the utility of diffusion-weighted magnetic resonance (DWMR) to differentiate the atypical uterine leiomyomas and sarcomas, establishing a cut-off value of the apparent diffusion coefficient (ADC) to rule out the malignancy. We performed a diagnostic accuracy retrospective study including 10 patients with pelvic sarcomas and 17 patients with leiomyomas. Atypical morphological features in magnetic resonance (MR) studies occurred in 58.8% of the patients, leading to a significant number of indeterminate diagnoses. In contrast, ADC values were consistent for leiomyomas, sarcomas, primary tumours, recurrences, intrauterine and in the extrauterine pelvic locations. The ADC cut-off value was set in 1 (×10-3 mm2/s). Thus, the ADC values equal or superior to 1 × 10-3 mm2/s were always associated with a leiomyoma. The structural MR accuracy was 66.7%, reaching 100% when using DWMR with dichotomised ADC values. Diffusion-weighted imaging with the quantitative measurement of ADC may be considered a useful preoperative test for the differentiation of atypical leiomyomas from sarcomas. Impact statement What is already known on this subject? Papers reporting the utility of a diffusion-weighted MR for the diagnosis of uterine sarcomas are scarce and consist of a small series. However, the published results are consistent with our study, with the decreased ADCs in the case of malignancy. What do the results of this study add? The main differential characteristic of our study is that we selected only the atypical leiomyomas: they share sonographic and MR features with sarcomas, which often leads to an inaccurate diagnosis. This is also the first paper reporting on the role of DWMR with ADC for these types of tumours in extrauterine pelvic locations. We demonstrated a consistent relationship between dichotomised ADC values in leiomyomas/sarcomas for these particular cases and in recurrent tumours, with no overlap between both the groups, as a difference with the previous reports. What are the implications of these findings for clinical practice and/or further research? Our study can be considered as a proof of concept supporting DWMR with ADC measurement as a useful tool to enhance the diagnostic accuracy of MR, highlighting its value to rule out malignancy. Hence, DWMR seems to be a potential useful test to include in the preoperative evaluation of clinically atypical uterine tumours.


Subject(s)
Carcinosarcoma/diagnostic imaging , Diffusion Magnetic Resonance Imaging , Leiomyoma/diagnostic imaging , Leiomyosarcoma/diagnostic imaging , Uterine Neoplasms/diagnostic imaging , Adult , Aged , Aged, 80 and over , Carcinosarcoma/pathology , Diagnostic Errors/prevention & control , Female , Humans , Leiomyoma/pathology , Leiomyosarcoma/pathology , Middle Aged , Predictive Value of Tests , Retrospective Studies , Uterine Neoplasms/pathology
19.
J Virol ; 91(10)2017 05 15.
Article in English | MEDLINE | ID: mdl-28275194

ABSTRACT

Viral quasispecies evolution upon long-term virus replication in a noncoevolving cellular environment raises relevant general issues, such as the attainment of population equilibrium, compliance with the molecular-clock hypothesis, or stability of the phenotypic profile. Here, we evaluate the adaptation, mutant spectrum dynamics, and phenotypic diversification of hepatitis C virus (HCV) in the course of 200 passages in human hepatoma cells in an experimental design that precluded coevolution of the cells with the virus. Adaptation to the cells was evidenced by increase in progeny production. The rate of accumulation of mutations in the genomic consensus sequence deviated slightly from linearity, and mutant spectrum analyses revealed a complex dynamic of mutational waves, which was sustained beyond passage 100. The virus underwent several phenotypic changes, some of which impacted the virus-host relationship, such as enhanced cell killing, a shift toward higher virion density, and increased shutoff of host cell protein synthesis. Fluctuations in progeny production and failure to reach population equilibrium at the genomic level suggest internal instabilities that anticipate an unpredictable HCV evolution in the complex liver environment.IMPORTANCE Long-term virus evolution in an unperturbed cellular environment can reveal features of virus evolution that cannot be explained by comparing natural viral isolates. In the present study, we investigate genetic and phenotypic changes that occur upon prolonged passage of hepatitis C virus (HCV) in human hepatoma cells in an experimental design in which host cell evolutionary change is prevented. Despite replication in a noncoevolving cellular environment, the virus exhibited internal population disequilibria that did not decline with increased adaptation to the host cells. The diversification of phenotypic traits suggests that disequilibria inherent to viral populations may provide a selective advantage to viruses that can be fully exploited in changing environments.


Subject(s)
Carcinoma, Hepatocellular/virology , Evolution, Molecular , Hepacivirus/genetics , Hepacivirus/physiology , Virus Replication , Adaptation, Biological/genetics , DNA Replication , Genome, Viral , Hepacivirus/classification , Hepacivirus/metabolism , Host-Pathogen Interactions , Humans , Liver/virology , Mutation , Phenotype , RNA, Viral/genetics
20.
Eur J Nutr ; 57(5): 1807-1816, 2018 Aug.
Article in English | MEDLINE | ID: mdl-28456846

ABSTRACT

PURPOSE: Median urinary iodine concentration (UIC) is used to describe the iodine status of a population. However, the link between UIC and iodine intake may vary during pregnancy. The aim of this study was to compare UIC during and after pregnancy, adjusting for factors that affect iodine intake. METHODS: Two repeated measures of UIC and data on maternal iodine intake estimated through questionnaires were collected during pregnancy and 1-4 years after pregnancy in a subsample of women (n = 598) from a mother and child cohort study in Spain. Random-effects interval regression was used to assess the changes in UIC according to pregnancy status. RESULTS: Median UIC was similar during (133 µg/L) and after pregnancy (139 µg/L). After adjusting for iodised salt, iodine supplement consumption, and socio-demographic related variables, UIC was 24.0% (95% CI 11.3, 38.2) higher after than during pregnancy. This difference was maintained in a subsample of women with exhaustive information on diet (n = 291): 26.2%, 95% CI 10.3, 44.4. CONCLUSIONS: In an iodine sufficient area for the general population, iodine excretion was lower during than after pregnancy when factors affecting iodine intake were controlled for. Current recommendations of median UIC during pregnancy are based on the equivalence between iodine intake and UIC estimated from studies in non-pregnant populations, which might lead to overestimation of iodine deficiency during gestation. Further studies should evaluate the equivalence between iodine intake and its urinary excretion during pregnancy.


Subject(s)
Iodine , Nutritional Status , Pregnancy/urine , Adult , Cohort Studies , Cross-Sectional Studies , Female , Humans , Iodides , Iodine/administration & dosage , Iodine/deficiency , Iodine/metabolism , Iodine/urine , Sodium Chloride, Dietary/administration & dosage , Sodium Chloride, Dietary/metabolism , Spain
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