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1.
Cell ; 177(4): 821-836.e16, 2019 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-30982602

RESUMEN

Whole-genome-sequencing (WGS) of human tumors has revealed distinct mutation patterns that hint at the causative origins of cancer. We examined mutational signatures in 324 WGS human-induced pluripotent stem cells exposed to 79 known or suspected environmental carcinogens. Forty-one yielded characteristic substitution mutational signatures. Some were similar to signatures found in human tumors. Additionally, six agents produced double-substitution signatures and eight produced indel signatures. Investigating mutation asymmetries across genome topography revealed fully functional mismatch and transcription-coupled repair pathways. DNA damage induced by environmental mutagens can be resolved by disparate repair and/or replicative pathways, resulting in an assortment of signature outcomes even for a single agent. This compendium of experimentally induced mutational signatures permits further exploration of roles of environmental agents in cancer etiology and underscores how human stem cell DNA is directly vulnerable to environmental agents. VIDEO ABSTRACT.


Asunto(s)
Carcinógenos Ambientales/clasificación , Neoplasias/genética , Carcinógenos Ambientales/efectos adversos , Daño del ADN/genética , Análisis Mutacional de ADN/métodos , Reparación del ADN/genética , Replicación del ADN , Perfil Genético , Genoma Humano/genética , Humanos , Mutación INDEL/genética , Mutagénesis , Mutación/genética , Células Madre Pluripotentes/metabolismo , Secuenciación Completa del Genoma/métodos
2.
Mol Cell ; 82(6): 1123-1139.e8, 2022 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-35182481

RESUMEN

A mesenchymal tumor phenotype associates with immunotherapy resistance, although the mechanism is unclear. Here, we identified FBXO7 as a maintenance regulator of mesenchymal and immune evasion phenotypes of cancer cells. FBXO7 bound and stabilized SIX1 co-transcriptional regulator EYA2, stimulating mesenchymal gene expression and suppressing IFNα/ß, chemokines CXCL9/10, and antigen presentation machinery, driven by AXL extracellular ligand GAS6. Ubiquitin ligase SCFFBXW7 antagonized this pathway by promoting EYA2 degradation. Targeting EYA2 Tyr phosphatase activity decreased mesenchymal phenotypes and enhanced cancer cell immunogenicity, resulting in attenuated tumor growth and metastasis, increased infiltration of cytotoxic T and NK cells, and enhanced anti-PD-1 therapy response in mouse tumor models. FBXO7 expression correlated with mesenchymal and immune-suppressive signatures in patients with cancer. An FBXO7-immune gene signature predicted immunotherapy responses. Collectively, the FBXO7/EYA2-SCFFBXW7 axis maintains mesenchymal and immune evasion phenotypes of cancer cells, providing rationale to evaluate FBXO7/EYA2 inhibitors in combination with immune-based therapies to enhance onco-immunotherapy responses.


Asunto(s)
Proteínas F-Box , Proteína 7 que Contiene Repeticiones F-Box-WD , Neoplasias , Animales , Línea Celular Tumoral , Proteínas F-Box/genética , Proteínas F-Box/metabolismo , Proteína 7 que Contiene Repeticiones F-Box-WD/genética , Proteínas de Homeodominio/genética , Humanos , Evasión Inmune , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Ratones , Neoplasias/genética , Proteínas Nucleares/metabolismo , Fenotipo , Proteínas Tirosina Fosfatasas/genética , Ubiquitina/metabolismo
4.
Ann Intern Med ; 177(4): 476-483, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38498876

RESUMEN

BACKGROUND: In the NUDGE-FLU (Nationwide Utilization of Danish Government Electronic letter system for increasing inFLUenza vaccine uptake) trial, electronic letters incorporating cardiovascular (CV) gain-framing and repeated messaging increased influenza vaccination by approximately 1 percentage point. OBJECTIVE: To evaluate the effects of the successful nudging interventions on downstream clinical outcomes. DESIGN: Prespecified exploratory analysis of a nationwide randomized implementation trial. (ClinicalTrials.gov: NCT05542004). SETTING: The 2022 to 2023 influenza season. PARTICIPANTS: 964 870 Danish citizens aged 65 years or older. INTERVENTION: Usual care or 9 different electronically delivered behavioral nudging letters. MEASUREMENTS: Cardiovascular, respiratory, and other clinical end points during follow-up from intervention delivery (16 September 2022) through 31 May 2023. RESULTS: The analysis set included 691 820 participants. Hospitalization for pneumonia or influenza occurred in 3354 of 346 327 (1.0%) participants in the usual care group, 396 of 38 586 (1.0%) in the CV gain-framing group (hazard ratio [HR], 1.06 [95% CI, 0.95 to 1.18]; versus usual care), and 403 of 38 231 (1.1%) in the repeated letter group (HR, 1.09 [CI, 0.98 to 1.21]; versus usual care). In the usual care group, 44 682 (12.9%) participants were hospitalized for any cause, compared with 5002 (13.0%) in the CV gain-framing group (HR, 1.00 [CI, 0.97 to 1.03]; versus usual care) and 4965 (13.0%) in the repeated letter group (HR, 1.01 [CI, 0.98 to 1.04]; versus usual care). A total of 6341 (1.8%) participants died in the usual care group, compared with 721 (1.9%) in the CV gain-framing group (HR, 1.02 [CI, 0.94 to 1.10]; versus usual care) and 646 (1.7%) in the repeated letter group (HR, 0.92 [CI, 0.85 to 1.00]; versus usual care). LIMITATION: Prespecified but exploratory analysis, potential misclassification of events in routinely collected registry data, and results may not be generalizable to other health systems or countries with other racial compositions and/or cultural or societal norms. CONCLUSION: In a prespecified exploratory analysis, modest increases in influenza vaccination rates seen with electronic nudges did not translate into observable improvements in clinical outcomes. Seasonal influenza vaccination should remain strongly recommended. PRIMARY FUNDING SOURCE: Sanofi.


Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Humanos , Gripe Humana/prevención & control , Vacunación , Sistema de Registros , Hospitalización
5.
Gut ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38857990

RESUMEN

OBJECTIVE: Epigenetic mechanisms, including DNA methylation (DNAm), have been proposed to play a key role in Crohn's disease (CD) pathogenesis. However, the specific cell types and pathways affected as well as their potential impact on disease phenotype and outcome remain unknown. We set out to investigate the role of intestinal epithelial DNAm in CD pathogenesis. DESIGN: We generated 312 intestinal epithelial organoids (IEOs) from mucosal biopsies of 168 patients with CD (n=72), UC (n=23) and healthy controls (n=73). We performed genome-wide molecular profiling including DNAm, bulk as well as single-cell RNA sequencing. Organoids were subjected to gene editing and the functional consequences of DNAm changes evaluated using an organoid-lymphocyte coculture and a nucleotide-binding oligomerisation domain, leucine-rich repeat and CARD domain containing 5 (NLRC5) dextran sulphate sodium (DSS) colitis knock-out mouse model. RESULTS: We identified highly stable, CD-associated loss of DNAm at major histocompatibility complex (MHC) class 1 loci including NLRC5 and cognate gene upregulation. Single-cell RNA sequencing of primary mucosal tissue and IEOs confirmed the role of NLRC5 as transcriptional transactivator in the intestinal epithelium. Increased mucosal MHC-I and NLRC5 expression in adult and paediatric patients with CD was validated in additional cohorts and the functional role of MHC-I highlighted by demonstrating a relative protection from DSS-mediated mucosal inflammation in NLRC5-deficient mice. MHC-I DNAm in IEOs showed a significant correlation with CD disease phenotype and outcomes. Application of machine learning approaches enabled the development of a disease prognostic epigenetic molecular signature. CONCLUSIONS: Our study has identified epigenetically regulated intestinal epithelial MHC-I as a novel mechanism in CD pathogenesis.

6.
Syst Biol ; 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37801684

RESUMEN

Instances of parallel phenotypic evolution offer great opportunities to understand the evolutionary processes underlying phenotypic changes. However, confirming parallel phenotypic evolution and studying its causes requires a robust phylogenetic framework. One such example is the "black-and-white wagtails", a group of five species in the songbird genus Motacilla: one species, Motacilla alba, shows wide intra-specific plumage variation, while the four others form two pairs of very similar-looking species (M. aguimp + M. samveasnae and M. grandis + M. maderaspatensis, respectively). However, the two species in each of these pairs were not recovered as sisters in previous phylogenetic inferences. Their relationships varied depending on the markers used, suggesting that gene tree heterogeneity might have hampered accurate phylogenetic inference. Here, we use whole genome resequencing data to explore the phylogenetic relationships within this group, with a special emphasis on characterizing the extent of gene tree heterogeneity and its underlying causes. We first used multispecies coalescent methods to generate a "complete evidence" phylogenetic hypothesis based on genome-wide variants, while accounting for incomplete lineage sorting (ILS) and introgression. We then investigated the variation in phylogenetic signal across the genome, to quantify the extent of discordance across genomic regions, and test its underlying causes. We found that wagtail genomes are mosaics of regions supporting variable genealogies, because of ILS and inter-specific introgression. The most common topology across the genome, supporting M. alba and M. aguimp as sister species, appears to be influenced by ancient introgression. Additionally, we inferred another ancient introgression event, between M. alba and M. grandis. By combining results from multiple analyses, we propose a phylogenetic network for the black-and-white wagtails that confirms that similar phenotypes evolved in non-sister lineages, supporting parallel plumage evolution. Furthermore, the inferred reticulations do not connect species with similar plumage coloration, suggesting that introgression does not underlie parallel plumage evolution in this group. Our results demonstrate the importance of investigation of genome-wide patterns of gene tree heterogeneity to help understanding the mechanisms underlying phenotypic evolution.

7.
BMC Oral Health ; 24(1): 195, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38321444

RESUMEN

BACKGROUND: Urgent dental care may be the only place where many people, especially vulnerable groups, access care. This presents an opportunity for delivery of a behavioural intervention promoting planned dental visiting, which may help address one of the factors contributing to a socio-economic gradient in oral health. Although we know that cueing events such as having a cancer diagnosis may create a 'teachable moment' stimulating positive changes in health behaviour, we do not know whether delivering an opportunistic intervention in urgent dental care is feasible and acceptable to patients. METHODS: The feasibility study aimed to recruit 60 patients in a Dental Hospital and dental practices delivering urgent care within and outside working hours. Follow-up was by telephone, e mail and post over 4 months. RESULTS: Although the recruitment window was shortened because of COVID-19, of 47 patients assessed for eligibility, 28 were enrolled (70.1% of screened patients provided consent). A relatively high proportion were from disadvantaged backgrounds (46.4%, 13/28 receiving State benefits). Retention was 82.1% (23/28), which was also the rate of completion of the Oral Health Impact Profile co-primary outcome. The other primary outcome involved linking participant details at recruitment, with centrally-held data on services provided, with 84.6% (22/26) records partly or fully successfully matched. All intervention participants received at least some of the intervention, although we identified aspects of dental nurse training which would improve intervention fidelity. CONCLUSIONS: Despite recruitment being impacted by the pandemic, when the majority of clinical trials experienced reduced rates of recruitment, we found a high recruitment and consenting rate, even though patients were approached opportunistically to be enrolled in the trial and potentially receive an intervention. Retention rates were also high even though a relatively high proportion had a low socio-economic background. Therefore, even though patients may be in pain, and had not anticipated involvement before their urgent care visit, the study indicated that this was a feasible and acceptable setting in which to position an opportunistic intervention. This has the potential to harness the potential of the 'teachable moment' in people's lives, and provide support to help address health inequalities. TRIAL REGISTRATION: ISRCTN 10,853,330 07/10/2019.


Asunto(s)
COVID-19 , Humanos , Estudios de Factibilidad , Encuestas y Cuestionarios , Atención Ambulatoria , Atención Odontológica
8.
Cancer Immunol Immunother ; 72(6): 1581-1601, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36562825

RESUMEN

Cancer immunotherapy relies on improving T cell effector functions against malignancies, but despite the identification of several key transcription factors (TFs), the biological functions of these TFs are not entirely understood. We developed and utilized a novel, clinically relevant murine model to dissect the functional properties of crucial T cell transcription factors during anti-tumor responses. Our data showed that the loss of TCF-1 in CD8 T cells also leads to loss of key stimulatory molecules such as CD28. Our data showed that TCF-1 suppresses surface NKG2D expression on naïve and activated CD8 T cells via key transcriptional factors Eomes and T-bet. Using both in vitro and in vivo models, we uncovered how TCF-1 regulates critical molecules responsible for peripheral CD8 T cell effector functions. Finally, our unique genetic and molecular approaches suggested that TCF-1 also differentially regulates essential kinases. These kinases, including LCK, LAT, ITK, PLC-γ1, P65, ERKI/II, and JAK/STATs, are required for peripheral CD8 T cell persistent function during alloimmunity. Overall, our molecular and bioinformatics data demonstrate the mechanism by which TCF-1 modulated several critical aspects of T cell function during CD8 T cell response to cancer. Summary Figure: TCF-1 is required for persistent function of CD8 T cells but dispensable for anti-tumor response. Here, we have utilized a novel mouse model that lacks TCF-1 specifically on CD8 T cells for an allogeneic transplant model. We uncovered a molecular mechanism of how TCF-1 regulates key signaling pathways at both transcriptomic and protein levels. These key molecules included LCK, LAT, ITK, PLC-γ1, p65, ERK I/II, and JAK/STAT signaling. Next, we showed that the lack of TCF-1 impacted phenotype, proinflammatory cytokine production, chemokine expression, and T cell activation. We provided clinical evidence for how these changes impact GVHD target organs (skin, small intestine, and liver). Finally, we provided evidence that TCF-1 regulates NKG2D expression on mouse naïve and activated CD8 T cells. We have shown that CD8 T cells from TCF-1 cKO mice mediate cytolytic functions via NKG2D.


Asunto(s)
Subfamilia K de Receptores Similares a Lectina de Células NK , Neoplasias , Factor 1 de Transcripción de Linfocitos T , Animales , Ratones , Linfocitos T CD8-positivos , Expresión Génica , Neoplasias/metabolismo , Transducción de Señal
9.
BMC Med ; 21(1): 288, 2023 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-37542319

RESUMEN

BACKGROUND: India had an estimated 2.9 million tuberculosis cases and 506 thousand deaths in 2021. Novel vaccines effective in adolescents and adults could reduce this burden. M72/AS01E and BCG-revaccination have recently completed phase IIb trials and estimates of their population-level impact are needed. We estimated the potential health and economic impact of M72/AS01E and BCG-revaccination in India and investigated the impact of variation in vaccine characteristics and delivery strategies. METHODS: We developed an age-stratified compartmental tuberculosis transmission model for India calibrated to country-specific epidemiology. We projected baseline epidemiology to 2050 assuming no-new-vaccine introduction, and M72/AS01E and BCG-revaccination scenarios over 2025-2050 exploring uncertainty in product characteristics (vaccine efficacy, mechanism of effect, infection status required for vaccine efficacy, duration of protection) and implementation (achieved vaccine coverage and ages targeted). We estimated reductions in tuberculosis cases and deaths by each scenario compared to the no-new-vaccine baseline, as well as costs and cost-effectiveness from health-system and societal perspectives. RESULTS: M72/AS01E scenarios were predicted to avert 40% more tuberculosis cases and deaths by 2050 compared to BCG-revaccination scenarios. Cost-effectiveness ratios for M72/AS01E vaccines were around seven times higher than BCG-revaccination, but nearly all scenarios were cost-effective. The estimated average incremental cost was US$190 million for M72/AS01E and US$23 million for BCG-revaccination per year. Sources of uncertainty included whether M72/AS01E was efficacious in uninfected individuals at vaccination, and if BCG-revaccination could prevent disease. CONCLUSIONS: M72/AS01E and BCG-revaccination could be impactful and cost-effective in India. However, there is great uncertainty in impact, especially given the unknowns surrounding the mechanism of effect and infection status required for vaccine efficacy. Greater investment in vaccine development and delivery is needed to resolve these unknowns in vaccine product characteristics.


Asunto(s)
Mycobacterium tuberculosis , Vacunas contra la Tuberculosis , Tuberculosis , Adulto , Humanos , Adolescente , Vacuna BCG , Inmunización Secundaria , Tuberculosis/epidemiología , Tuberculosis/prevención & control , Vacunación , India/epidemiología
10.
PLoS Comput Biol ; 18(4): e1010002, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35452459

RESUMEN

We investigated the effects of updating age-specific social contact matrices to match evolving demography on vaccine impact estimates. We used a dynamic transmission model of tuberculosis in India as a case study. We modelled four incremental methods to update contact matrices over time, where each method incorporated its predecessor: fixed contact matrix (M0), preserved contact reciprocity (M1), preserved contact assortativity (M2), and preserved average contacts per individual (M3). We updated the contact matrices of a deterministic compartmental model of tuberculosis transmission, calibrated to epidemiologic data between 2000 and 2019 derived from India. We additionally calibrated the M0, M2, and M3 models to the 2050 TB incidence rate projected by the calibrated M1 model. We stratified age into three groups, children (<15y), adults (≥15y, <65y), and the elderly (≥65y), using World Population Prospects demographic data, between which we applied POLYMOD-derived social contact matrices. We simulated an M72-AS01E-like tuberculosis vaccine delivered from 2027 and estimated the per cent TB incidence rate reduction (IRR) in 2050 under each update method. We found that vaccine impact estimates in all age groups remained relatively stable between the M0-M3 models, irrespective of vaccine-targeting by age group. The maximum difference in impact, observed following adult-targeted vaccination, was 7% in the elderly, in whom we observed IRRs of 19% (uncertainty range 13-32), 20% (UR 13-31), 22% (UR 14-37), and 26% (UR 18-38) following M0, M1, M2 and M3 updates, respectively. We found that model-based TB vaccine impact estimates were relatively insensitive to demography-matched contact matrix updates in an India-like demographic and epidemiologic scenario. Current model-based TB vaccine impact estimates may be reasonably robust to the lack of contact matrix updates, but further research is needed to confirm and generalise this finding.


Asunto(s)
Tuberculosis , Adulto , Factores de Edad , Anciano , Niño , Humanos , Incidencia , Modelos Teóricos , Tuberculosis/epidemiología , Tuberculosis/prevención & control , Vacunación
11.
J Pediatr Gastroenterol Nutr ; 77(3): 393-395, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37256853

RESUMEN

There has been a recent surge in cases of pediatric acute hepatitis and pediatric acute liver failure (PALF) of unknown cause. Several reports have described clusters of these children who were positive for adenovirus (AdV) DNA, primarily in peripheral blood but some in liver tissue. We tested archived liver tissue specimens from a historical cohort of 44 children with PALF who were enrolled in a multicenter biorepository between 2007 and 2014 for AdV 40/41 using quantitative polymerase chain reaction. Most children had final diagnosis indeterminate. All samples were negative. Our findings suggest that AdV was unlikely to be an unidentified cause of indeterminate PALF during this past era. The significance of AdV viremia in contemporary cohorts of children with PALF remains unknown and requires further study.


Asunto(s)
Hepatitis , Fallo Hepático Agudo , Niño , Humanos , Adenoviridae , Fallo Hepático Agudo/diagnóstico , Fallo Hepático Agudo/etiología , Hepatitis/complicaciones , Enfermedad Aguda
12.
Am J Addict ; 32(6): 610-614, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37543854

RESUMEN

BACKGROUND AND OBJECTIVES: This study estimated years of life lost (YLL) among US Latinx individuals during the most recent wave of drug overdose deaths. METHODS: A serial cross-sectional study of YLL (life expectancy minus age at death) from death certificate records of Latinx individuals who died from drug overdoses from 2015 to mid-2022. RESULTS: Over the study period, 58,209 Latinx individuals aged 15-64 years died from drug overdoses resulting in 2,266,784 YLL. Age-group YLL differences remained stable, but gender YLL trajectories diverged. CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE: This study extends our understanding of the immense loss to Latinx communities from preventable drug deaths.


Asunto(s)
Sobredosis de Droga , Humanos , Estudios Transversales , Hispánicos o Latinos , Esperanza de Vida , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad
13.
J Genet Couns ; 2023 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-37864663

RESUMEN

In the genomic era, the availability of gene panel and whole genome/exome sequencing is rapidly increasing. Opportunities for providing former patients with new genetic information are also increasing over time and recontacting former patients with new information is likely to become more common. Breast cancer Refined Analysis of Sequence Tests-Risk And Penetrance (BRA-STRAP) is an Australian study of individuals who had previously undertaken BRCA1 and BRCA2 genetic testing, with no pathogenic variants detected. Using a waiver of consent, stored DNA samples were retested using a breast/ovarian cancer gene panel and clinically significant results returned to the patient (or next of kin, if deceased). This qualitative study aimed to explore patient experiences, opinions, and expectations of recontacting in the Australian hereditary cancer setting. Participants were familial cancer clinic patients (or next of kin) who were notified of a new pathogenic variant identified via BRA-STRAP. In-depth, semi-structured interviews were conducted approximately 6 weeks post-result. Interviews were transcribed verbatim and analyzed using an inductive thematic approach. Thirty participants (all female; average age = 57; range 36-84) were interviewed. Twenty-five were probands, and five were next of kin. Most women reported initial shock upon being recontacted with unexpected news, after having obtained a sense of closure related to their initial genetic testing experiences and cancer diagnosis. For most, this initial distress was short-lived, followed by a process of readjustment, meaning-making and adaptation that was facilitated by perceived clinical and personal utility of the information. Women were overall satisfied with the waiver of consent approach and recontacting process. Results are in line with previous studies suggesting that patients have positive attitudes about recontacting. Women in this study valued new genetic information gained from retesting and were satisfied with the BRA-STRAP recontact model. Practice implications to facilitate readjustment and promote psychosocial adaptation were identified.

14.
BMC Oral Health ; 23(1): 170, 2023 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-36966284

RESUMEN

INTRODUCTION: The key objective of this research was to describe the prescription rate of various antibiotics for dental problems in India and to study the relevance of the prescriptions by analysing antibiotic types associated with different dental diagnoses, using a large-scale nationally representative dataset. METHODS: We used a 12-month period (May 2015 to April 2016) medical audit dataset from IQVIA (formerly IMS Health). We coded the dental diagnosis provided in the medical audit data to the International Statistical Classification of Diseases and Related Health Problems (ICD-11) and the prescribed antibiotics for the diagnosis to the Anatomic Therapeutic Chemical (ATC) -2020 classification of the World Health Organization. The primary outcome measure was the medicine prescription rate per 1,000 persons per year (PRPY1000). RESULTS: Our main findings were-403 prescriptions per 1,000 persons per year in the year 2015 -2016 for all dental ailments. Across all ATC level 1 classification, 'Diseases of hard tissues' made up the majority of the prescriptions. 'Beta-lactam', 'Penicillin,' and 'Cephalosporins' were the most commonly prescribed antibiotics for dental diagnoses followed by 'Macrolides' and 'Quinolones'. 'Dental caries', 'Discoloration of tooth', and 'Toothache' were the most common reasons for 'Beta-Lactams' and 'Penicillin' prescriptions. CONCLUSION: To conclude our study reports first ever country (India) level estimates of antibiotic prescription by antibiotic classes, age groups, and ICD-11 classification for dental ailments.


Asunto(s)
Antibacterianos , Prescripciones de Medicamentos , Humanos , Antibacterianos/uso terapéutico , Cefalosporinas , Penicilinas , India/epidemiología
15.
Am J Respir Cell Mol Biol ; 67(4): 438-445, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35767671

RESUMEN

Influenza infection induces lung epithelial cell injury via programmed cell death. Glutathione, a potent antioxidant, has been reported to be associated with influenza infection. We hypothesized that lung epithelial cell death during influenza infection is regulated by glutathione metabolism. Eight-week-old male and female BALB/c mice were infected with influenza (PR8: A/PR/8/34 [H1N1]) via intranasal instillation. Metabolomic analyses were performed on whole lung lysate after influenza infection. For in vitro analysis, Beas-2B cells were infected with influenza. RNA was extracted, and QuantiTect Primer Assay was used to assess gene expression. Glutathione concentrations were assessed by colorimetric assay. Influenza infection resulted in increased inflammation and epithelial cell injury in our murine model, leading to increased morbidity and mortality. In both our in vivo and in vitro models, influenza infection was found to induce apoptosis and necroptosis. Influenza infection led to decreased glutathione metabolism and reduced glutathione reductase activity in lung epithelial cells. Genetic inhibition of glutathione reductase suppressed apoptosis and necroptosis of lung epithelial cells. Pharmacologic inhibition of glutathione reductase reduced airway inflammation, lung injury, and cell death in our murine influenza model. Our results demonstrate that glutathione reductase activity is suppressed during influenza. Glutathione reductase inhibition prevents epithelial cell death and morbidity in our murine influenza model. Our results suggest that glutathione reductase-dependent glutathione metabolism may play an important role in the host response to viral infection by regulating lung epithelial cell death.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Gripe Humana , Lesión Pulmonar , Infecciones por Orthomyxoviridae , Animales , Antioxidantes/metabolismo , Femenino , Glutatión/metabolismo , Glutatión Reductasa/metabolismo , Humanos , Subtipo H1N1 del Virus de la Influenza A/metabolismo , Gripe Humana/metabolismo , Pulmón/metabolismo , Lesión Pulmonar/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Infecciones por Orthomyxoviridae/metabolismo , ARN/metabolismo
16.
J Med Genet ; 58(12): 853-858, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33168572

RESUMEN

BACKGROUND: The strength of evidence supporting the validity of gene-disease relationships is variable. Hereditary cancer has the additional complexity of low or moderate penetrance for some confirmed disease-associated alleles. METHODS: To promote national consistency in interpretation of hereditary cancer/tumour gene test results, we requested opinions of representatives from Australian Family Cancer Clinics regarding the clinical utility of 157 genes initially collated for a national research project. Viewpoints were sought by initial survey, face-to-face workshop and follow-up survey. Subsequent review was undertaken by the eviQ Cancer Genetics Reference Committee, a national resource providing evidence-based and consensus-driven cancer treatment protocols. RESULTS: Genes were categorised by clinical actionability as: relevant for testing on presentation of common cancer/tumour types (n=45); relevant for testing in the context of specific rare phenotypes (n=74); insufficient clinical utility (n=34) or contentious clinical utility (n=3). Opinions for several genes altered during the study time frame, due to new information. CONCLUSION: Through an iterative process, consensus was achieved on genes with clinical utility for hereditary cancer/tumour conditions in the Australian setting. This study highlighted need for regular review of gene-disease lists, a role assumed in Australia for hereditary cancer/tumour predisposition genes by the eviQ Cancer Genetics Reference Committee.


Asunto(s)
Asesoramiento Genético/métodos , Predisposición Genética a la Enfermedad/genética , Pruebas Genéticas/métodos , Anotación de Secuencia Molecular/métodos , Neoplasias/genética , Australia , Consenso , Salud de la Familia , Femenino , Estudios de Asociación Genética/métodos , Mutación de Línea Germinal , Humanos , Masculino , Oncología Médica/métodos , Neoplasias/diagnóstico , Linaje , Proteínas Supresoras de Tumor/genética
17.
Am J Respir Cell Mol Biol ; 64(5): 579-591, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33625952

RESUMEN

Community-acquired pneumonia is the most common type of pneumonia and remains a leading cause of morbidity and mortality worldwide. Although many different pathogens can contribute to pneumonia, Streptococcus pneumoniae is one of the common bacterial pathogens that underlie community-acquired pneumonia. RIPK3 (receptor-interacting protein kinase 3) is widely recognized as a key modulator of inflammation and cell death. To elucidate a potential role of RIPK3 in pneumonia, we examined plasma from healthy control subjects and patients positive for streptococcal pneumonia. In human studies, RIPK3 protein concentrations were significantly elevated and were identified as a potential plasma marker of pneumococcal pneumonia. To expand these findings, we used an in vivo murine model of pneumococcal pneumonia to demonstrate that RIPK3 deficiency leads to reduced bacterial clearance, severe pathological damage, and high mortality. Our results illustrated that RIPK3 forms a complex with RIPK1, MLKL (mixed-lineage kinase domain-like protein), and MCU (mitochondrial calcium uniporter) to induce mitochondrial calcium uptake and mitochondrial reactive oxygen species(mROS) production during S. pneumoniae infection. In macrophages, RIPK3 initiated necroptosis via the mROS-mediated mitochondrial permeability transition pore opening and NLRP3 inflammasome activation via the mROS-AKT pathway to protect against S. pneumoniae. In conclusion, our study demonstrated a mechanism by which RIPK3-initiated necroptosis is essential for host defense against S. pneumoniae.


Asunto(s)
Macrófagos Alveolares/inmunología , Mitocondrias/inmunología , Neumonía Neumocócica/inmunología , Proteínas Quinasas/inmunología , Proteína Serina-Treonina Quinasas de Interacción con Receptores/inmunología , Streptococcus pneumoniae/patogenicidad , Anciano , Animales , Canales de Calcio/genética , Canales de Calcio/inmunología , Estudios de Casos y Controles , Modelos Animales de Enfermedad , Femenino , Regulación de la Expresión Génica , Humanos , Inflamasomas/genética , Inflamasomas/inmunología , Macrófagos Alveolares/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , Mitocondrias/patología , Poro de Transición de la Permeabilidad Mitocondrial/inmunología , Poro de Transición de la Permeabilidad Mitocondrial/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/inmunología , Necroptosis/genética , Necroptosis/inmunología , Neumonía Neumocócica/complicaciones , Neumonía Neumocócica/microbiología , Proteínas Quinasas/genética , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/inmunología , Especies Reactivas de Oxígeno/inmunología , Especies Reactivas de Oxígeno/metabolismo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/genética , Transducción de Señal , Streptococcus pneumoniae/inmunología
18.
Clin Infect Dis ; 72(1): 155-172, 2021 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-32502258

RESUMEN

Evidence is limited for infection prevention and control (IPC) measures reducing Mycobacterium tuberculosis (MTB) transmission in health facilities. This systematic review, 1 of 7 commissioned by the World Health Organization to inform the 2019 update of global tuberculosis (TB) IPC guidelines, asked: do triage and/or isolation and/or effective treatment of TB disease reduce MTB transmission in healthcare settings? Of 25 included articles, 19 reported latent TB infection (LTBI) incidence in healthcare workers (HCWs; absolute risk reductions 1%-21%); 5 reported TB disease incidence in HCWs (no/slight [high TB burden] or moderate [low burden] reduction) and 2 in human immunodeficiency virus-positive in-patients (6%-29% reduction). In total, 23/25 studies implemented multiple IPC measures; effects of individual measures could not be disaggregated. Packages of IPC measures appeared to reduce MTB transmission, but evidence for effectiveness of triage, isolation, or effective treatment, alone or in combination, was indirect and low quality. Harmonizing study designs and reporting frameworks will permit formal data syntheses and facilitate policy making.


Asunto(s)
Tuberculosis Latente , Mycobacterium tuberculosis , Atención a la Salud , Instituciones de Salud , Personal de Salud , Humanos , Control de Infecciones , Triaje
19.
PLoS Med ; 18(4): e1003566, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33901173

RESUMEN

BACKGROUND: Two weeks' isolation is widely recommended for people commencing treatment for pulmonary tuberculosis (TB). The evidence that this corresponds to clearance of potentially infectious tuberculous mycobacteria in sputum is not well established. This World Health Organization-commissioned review investigated sputum sterilisation dynamics during TB treatment. METHODS AND FINDINGS: For the main analysis, 2 systematic literature searches of OvidSP MEDLINE, Embase, and Global Health, and EBSCO CINAHL Plus were conducted to identify studies with data on TB infectiousness (all studies to search date, 1 December 2017) and all randomised controlled trials (RCTs) for drug-susceptible TB (from 1 January 1990 to search date, 20 February 2018). Included articles reported on patients receiving effective treatment for culture-confirmed drug-susceptible pulmonary TB. The outcome of interest was sputum bacteriological conversion: the proportion of patients having converted by a defined time point or a summary measure of time to conversion, assessed by smear or culture. Any study design with 10 or more particpants was considered. Record sifting and data extraction were performed in duplicate. Random effects meta-analyses were performed. A narrative summary additionally describes the results of a systematic search for data evaluating infectiousness from humans to experimental animals (PubMed, all studies to 27 March 2018). Other evidence on duration of infectiousness-including studies reporting on cough dynamics, human tuberculin skin test conversion, or early bactericidal activity of TB treatments-was outside the scope of this review. The literature search was repeated on 22 November 2020, at the request of the editors, to identify studies published after the previous censor date. Four small studies reporting 3 different outcome measures were identified, which included no data that would alter the findings of the review; they are not included in the meta-analyses. Of 5,290 identified records, 44 were included. Twenty-seven (61%) were RCTs and 17 (39%) were cohort studies. Thirteen studies (30%) reported data from Africa, 12 (27%) from Asia, 6 (14%) from South America, 5 (11%) from North America, and 4 (9%) from Europe. Four studies reported data from multiple continents. Summary estimates suggested smear conversion in 9% of patients at 2 weeks (95% CI 3%-24%, 1 single study [N = 1]), and 82% of patients at 2 months of treatment (95% CI 78%-86%, N = 10). Among baseline smear-positive patients, solid culture conversion occurred by 2 weeks in 5% (95% CI 0%-14%, N = 2), increasing to 88% at 2 months (95% CI 84%-92%, N = 20). At equivalent time points, liquid culture conversion was achieved in 3% (95% CI 1%-16%, N = 1) and 59% (95% CI 47%-70%, N = 8). Significant heterogeneity was observed. Further interrogation of the data to explain this heterogeneity was limited by the lack of disaggregation of results, including by factors such as HIV status, baseline smear status, and the presence or absence of lung cavitation. CONCLUSIONS: This systematic review found that most patients remained culture positive at 2 weeks of TB treatment, challenging the view that individuals are not infectious after this interval. Culture positivity is, however, only 1 component of infectiousness, with reduced cough frequency and aerosol generation after TB treatment initiation likely to also be important. Studies that integrate our findings with data on cough dynamics could provide a more complete perspective on potential transmission of Mycobacterium tuberculosis by individuals on treatment. TRIAL REGISTRATION: Systematic review registration: PROSPERO 85226.


Asunto(s)
Mycobacterium tuberculosis/fisiología , Esputo/microbiología , Tuberculosis Pulmonar/terapia , Humanos
20.
Biochem Biophys Res Commun ; 554: 41-48, 2021 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-33774278

RESUMEN

Fbxo7 is a key player in the differentiation and function of numerous blood cell types, and in neurons, oligodendrocytes and spermatocytes. In an effort to gain insight into the physiological and pathological settings where Fbxo7 is likely to play a key role, we sought to define the transcription factors which direct FBXO7 expression. Using sequence alignments across 28 species, we defined the human FBXO7 promoter and found that it contains two conserved regions enriched for multiple transcription factor binding sites. Many of these have roles in either neuronal or haematopoietic development. Using various FBXO7 promoter reporters, we found ELF4, Pax5 and c-Myb have functional binding sites that activate transcription. We find endogenous Pax5 is bound to the FBXO7 promoter in pre-B cells, and that the exogenous expression of Pax5 represses Fbxo7 transcription in early pro-B cells.


Asunto(s)
Linfocitos B/metabolismo , Proteínas F-Box/genética , Factor de Transcripción PAX5/metabolismo , Proteínas Proto-Oncogénicas c-myb/metabolismo , Linfocitos B/citología , Secuencia de Bases , Sitios de Unión , Diferenciación Celular/fisiología , Células Cultivadas , Secuencia Conservada , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Proteínas F-Box/metabolismo , Humanos , Factor de Transcripción PAX5/genética , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas c-myb/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
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