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Mitochondrial activity differs markedly between organs, but it is not known how and when this arises. Here we show that cell lineage-specific expression profiles involving essential mitochondrial genes emerge at an early stage in mouse development, including tissue-specific isoforms present before organ formation. However, the nuclear transcriptional signatures were not independent of organelle function. Genetically disrupting intra-mitochondrial protein synthesis with two different mtDNA mutations induced cell lineage-specific compensatory responses, including molecular pathways not previously implicated in organellar maintenance. We saw downregulation of genes whose expression is known to exacerbate the effects of exogenous mitochondrial toxins, indicating a transcriptional adaptation to mitochondrial dysfunction during embryonic development. The compensatory pathways were both tissue and mutation specific and under the control of transcription factors which promote organelle resilience. These are likely to contribute to the tissue specificity which characterizes human mitochondrial diseases and are potential targets for organ-directed treatments.
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Mitocondrias , Organogénesis , Animales , Femenino , Humanos , Ratones , Embarazo , Linaje de la Célula , ADN Mitocondrial/genética , Mitocondrias/metabolismo , Enfermedades Mitocondriales , Especificidad de Órganos , Desarrollo Embrionario , Embrión de Mamíferos/citología , Embrión de Mamíferos/metabolismoRESUMEN
Preventing SARS-CoV-2 infection by modulating viral host receptors, such as angiotensin-converting enzyme 2 (ACE2)1, could represent a new chemoprophylactic approach for COVID-19 that complements vaccination2,3. However, the mechanisms that control the expression of ACE2 remain unclear. Here we show that the farnesoid X receptor (FXR) is a direct regulator of ACE2 transcription in several tissues affected by COVID-19, including the gastrointestinal and respiratory systems. We then use the over-the-counter compound z-guggulsterone and the off-patent drug ursodeoxycholic acid (UDCA) to reduce FXR signalling and downregulate ACE2 in human lung, cholangiocyte and intestinal organoids and in the corresponding tissues in mice and hamsters. We show that the UDCA-mediated downregulation of ACE2 reduces susceptibility to SARS-CoV-2 infection in vitro, in vivo and in human lungs and livers perfused ex situ. Furthermore, we reveal that UDCA reduces the expression of ACE2 in the nasal epithelium in humans. Finally, we identify a correlation between UDCA treatment and positive clinical outcomes after SARS-CoV-2 infection using retrospective registry data, and confirm these findings in an independent validation cohort of recipients of liver transplants. In conclusion, we show that FXR has a role in controlling ACE2 expression and provide evidence that modulation of this pathway could be beneficial for reducing SARS-CoV-2 infection, paving the way for future clinical trials.
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Enzima Convertidora de Angiotensina 2 , COVID-19 , Receptores Virales , Ácido Ursodesoxicólico , Animales , Humanos , Ratones , Enzima Convertidora de Angiotensina 2/genética , Enzima Convertidora de Angiotensina 2/metabolismo , COVID-19/metabolismo , COVID-19/prevención & control , Receptores Virales/genética , Receptores Virales/metabolismo , Estudios Retrospectivos , SARS-CoV-2/metabolismo , Tratamiento Farmacológico de COVID-19 , Cricetinae , Transcripción Genética , Ácido Ursodesoxicólico/farmacología , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Organoides/efectos de los fármacos , Organoides/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Mucosa Nasal/efectos de los fármacos , Mucosa Nasal/metabolismo , Sistema de Registros , Reproducibilidad de los Resultados , Trasplante de HígadoRESUMEN
Contrary to the long-held view that most humans harbour only identical mitochondrial genomes, deep resequencing has uncovered unanticipated extreme genetic variation within mitochondrial DNA (mtDNA). Most, if not all, humans contain multiple mtDNA genotypes (heteroplasmy); specific patterns of variants accumulate in different tissues, including cancers, over time; and some variants are preferentially passed down or suppressed in the maternal germ line. These findings cast light on the origin and spread of mtDNA mutations at multiple scales, from the organelle to the human population, and challenge the conventional view that high percentages of a mutation are required before a new variant has functional consequences.
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ADN Mitocondrial , Heterogeneidad Genética , Orgánulos/genética , Animales , Variación Biológica Poblacional , Predisposición Genética a la Enfermedad , HumanosRESUMEN
Influenza A virus (IAV) and SARS-CoV-2 (COVID-19) cause pandemic infections where cytokine storm syndrome and lung inflammation lead to high mortality. Given the high social and economic cost of respiratory viruses, there is an urgent need to understand how the airways defend against virus infection. Here we use mice lacking the WD and linker domains of ATG16L1 to demonstrate that ATG16L1-dependent targeting of LC3 to single-membrane, non-autophagosome compartments - referred to as non-canonical autophagy - protects mice from lethal IAV infection. Mice with systemic loss of non-canonical autophagy are exquisitely sensitive to low-pathogenicity IAV where extensive viral replication throughout the lungs, coupled with cytokine amplification mediated by plasmacytoid dendritic cells, leads to fulminant pneumonia, lung inflammation and high mortality. IAV was controlled within epithelial barriers where non-canonical autophagy reduced IAV fusion with endosomes and activation of interferon signalling. Conditional mouse models and ex vivo analysis showed that protection against IAV infection of lung was independent of phagocytes and other leucocytes. This establishes non-canonical autophagy in airway epithelial cells as a novel innate defence that restricts IAV infection and lethal inflammation at respiratory surfaces.
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Proteínas Relacionadas con la Autofagia/genética , Virus de la Influenza A/patogenicidad , Proteínas Asociadas a Microtúbulos/metabolismo , Infecciones por Orthomyxoviridae/genética , Eliminación de Secuencia , Células Epiteliales Alveolares/metabolismo , Células Epiteliales Alveolares/virología , Animales , Autofagia , Proteínas Relacionadas con la Autofagia/química , Proteínas Relacionadas con la Autofagia/metabolismo , Embrión de Pollo , Citocinas/metabolismo , Perros , Células de Riñón Canino Madin Darby , Ratones , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/mortalidad , Dominios Proteicos , Replicación ViralRESUMEN
Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis worldwide, responsible for approximately 20 million infections annually. Among the three open reading frames (ORFs) of the HEV genome, the ORF3 protein is involved in virus release. However, the host proteins involved in HEV release need to be clarified. In this study, a host protein, thioredoxin domain-containing protein 5 (TXNDC5), interacted with the non-palmitoylated ORF3 protein by co-immunoprecipitation analysis. We determined that the overexpression or knockdown of TXNDC5 positively regulated HEV release from the host cells. The 17FCL19 mutation of the ORF3 protein lost the ability to interact with TXNDC5. The releasing amounts of HEV with the ORF3 mutation (FCL17-19SSP) were decreased compared with wild-type HEV. The overexpression of TXNDC5 can stabilize and increase ORF3 protein amounts, but not the TXNDC5 mutant with amino acids 1-88 deletion. Meanwhile, we determined that the function of TXNDC5 on the stabilization of ORF3 protein is independent of the Trx-like domains. Knockdown of TXNDC5 could lead to the degradation of ORF3 protein by the endoplasmic reticulum (ER)-associated protein degradation-proteasome system. However, the ORF3 protein cannot be degraded in the knockout-TXNDC5 stable cells, suggesting that it may hijack other proteins for its stabilization. Subsequently, we found that the other members of protein disulfide isomerase (PDI), including PDIA1, PDIA3, PDIA4, and PDIA6, can increase ORF3 protein amounts, and PDIA3 and PDIA6 interact with ORF3 protein. Collectively, our study suggested that HEV ORF3 protein can utilize TXNDC5 for its stability in ER to facilitate viral release. IMPORTANCE: Hepatitis E virus (HEV) infection is the leading cause of acute viral hepatitis worldwide. After the synthesis and modification in the cells, the mature ORF3 protein is essential for HEV release. However, the host protein involved in this process has yet to be determined. Here, we reported a novel host protein, thioredoxin domain-containing protein 5 (TXNDC5), as a chaperone, contributing to HEV release by facilitating ORF3 protein stability in the endoplasmic reticulum through interacting with non-palmitoylated ORF3 protein. However, we also found that in the knockout-TXNDC5 stable cell lines, the HEV ORF3 protein may hijack other proteins for its stabilization. For the first time, our study demonstrated the involvement of TXNDC5 in viral particle release. These findings provide some new insights into the process of the HEV life cycle, the interaction between HEV and host factors, and a new direction for antiviral design.
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Virus de la Hepatitis E , Hepatitis E , Hepatitis Viral Humana , Humanos , Virus de la Hepatitis E/genética , Factores Inmunológicos , Proteína Disulfuro Isomerasas/genética , Tiorredoxinas/genética , Virión/metabolismoRESUMEN
Vaccination is the most effective method to protect humans and animals from diseases. Anti-idiotype vaccines are safer due to their absence of pathogens. However, the commercial production of traditional anti-idiotype vaccines using monoclonal and polyclonal antibodies (mAb and pAb) is complex and has a high failure rate. The present study designed a novel, simple, low-cost strategy for developing anti-idiotype vaccines with nanobody technology. We used porcine circovirus type 2 (PCV2) as a viral model, which can result in serious economic loss in the pig industry. The neutralizing mAb-1E7 (Ab1) against PCV2 capsid protein (PCV2-Cap) was immunized in the camel. And 12 nanobodies against mAb-1E7 were screened. Among them, Nb61 (Ab2) targeted the idiotype epitope of mAb-1E7 and blocked mAb-1E7's binding to PCV2-Cap. Additionally, a high-dose Nb61 vaccination can also protect mice and pigs from PCV2 infection. Epitope mapping showed that mAb-1E7 recognized the 75NINDFL80 of PCV2-Cap and 101NYNDFLG107 of Nb61. Subsequently, the mAb-3G4 (Ab3) against Nb61 was produced and can neutralize PCV2 infection in the PK-15 cells. Structure analysis showed that the amino acids of mAb-1E7 and mAb-3G4 respective binding to PCV2-Cap and Nb61 were also similar on the amino acids sequences and spatial conformation. Collectively, our study first provided a strategy for producing nanobody-based anti-idiotype vaccines and identified that anti-idiotype nanobodies could mimic the antigen on amino acids and structures. Importantly, as more and more neutralization mAbs against different pathogens are prepared, anti-idiotype nanobody vaccines can be easily produced against the disease with our strategy, especially for dangerous pathogens.IMPORTANCEAnti-idiotype vaccines utilize idiotype-anti-idiotype network theory, eliminating the need for external antigens as vaccine candidates. Especially for dangerous pathogens, they were safer because they did not contact the live pathogenic microorganisms. However, developing anti-idiotype vaccines with traditional monoclonal and polyclonal antibodies is complex and has a high failure rate. We present a novel, universal, simple, low-cost strategy for producing anti-idiotype vaccines with nanobody technology. Using a neutralization antibody against PCV2-Cap, a nanobody (Ab2) was successfully produced and could mimic the neutralizing epitope of PCV2-Cap. The nanobody can induce protective immune responses against PCV2 infection in mice and pigs. It highlighted that the anti-idiotype vaccine using nanobody has a very good application in the future, especially for dangerous pathogens.
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Infecciones por Circoviridae , Circovirus , Anticuerpos de Dominio Único , Vacunas Virales , Animales , Humanos , Ratones , Proteínas de la Cápside , Infecciones por Circoviridae/prevención & control , Infecciones por Circoviridae/veterinaria , Epítopos , Porcinos , Vacunas Virales/química , Vacunas Virales/inmunologíaRESUMEN
Human mitochondria possess a multi-copy circular genome, mitochondrial DNA (mtDNA), that is essential for cellular energy metabolism. The number of copies of mtDNA per cell, and their integrity, are maintained by nuclear-encoded mtDNA replication and repair machineries. Aberrant mtDNA replication and mtDNA breakage are believed to cause deletions within mtDNA. The genomic location and breakpoint sequences of these deletions show similar patterns across various inherited and acquired diseases, and are also observed during normal ageing, suggesting a common mechanism of deletion formation. However, an ongoing debate over the mechanism by which mtDNA replicates has made it difficult to develop clear and testable models for how mtDNA rearrangements arise and propagate at a molecular and cellular level. These deletions may impair energy metabolism if present in a high proportion of the mtDNA copies within the cell, and can be seen in primary mitochondrial diseases, either in sporadic cases or caused by autosomal variants in nuclear-encoded mtDNA maintenance genes. These mitochondrial diseases have diverse genetic causes and multiple modes of inheritance, and show notoriously broad clinical heterogeneity with complex tissue specificities, which further makes establishing genotype-phenotype relationships challenging. In this review, we aim to cover our current understanding of how the human mitochondrial genome is replicated, the mechanisms by which mtDNA replication and repair can lead to mtDNA instability in the form of large-scale rearrangements, how rearranged mtDNAs subsequently accumulate within cells, and the pathological consequences when this occurs.
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Replicación del ADN , ADN Mitocondrial , Enfermedades Mitocondriales , Humanos , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Enfermedades Mitocondriales/genética , Enfermedades Mitocondriales/metabolismo , Enfermedades Mitocondriales/patología , Eliminación de Secuencia , Genoma Mitocondrial , Mitocondrias/genética , Mitocondrias/metabolismo , Reparación del ADNRESUMEN
Mosquito blood-feeding behavior is a key determinant of the epidemiology of dengue viruses (DENV), the most-prevalent mosquito-borne viruses. However, despite its importance, how DENV infection influences mosquito blood-feeding and, consequently, transmission remains unclear. Here, we developed a high-resolution, video-based assay to observe the blood-feeding behavior of Aedes aegypti mosquitoes on mice. We then applied multivariate analysis on the high-throughput, unbiased data generated from the assay to ordinate behavioral parameters into complex behaviors. We showed that DENV infection increases mosquito attraction to the host and hinders its biting efficiency, the latter resulting in the infected mosquitoes biting more to reach similar blood repletion as uninfected mosquitoes. To examine how increased biting influences DENV transmission to the host, we established an in vivo transmission model with immuno-competent mice and demonstrated that successive short probes result in multiple transmissions. Finally, to determine how DENV-induced alterations of host-seeking and biting behaviors influence dengue epidemiology, we integrated the behavioral data within a mathematical model. We calculated that the number of infected hosts per infected mosquito, as determined by the reproduction rate, tripled when mosquito behavior was influenced by DENV infection. Taken together, this multidisciplinary study details how DENV infection modulates mosquito blood-feeding behavior to increase vector capacity, proportionally aggravating DENV epidemiology. By elucidating the contribution of mosquito behavioral alterations on DENV transmission to the host, these results will inform epidemiological modeling to tailor improved interventions against dengue.
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Aedes/virología , Virus del Dengue/fisiología , Dengue/transmisión , Dengue/virología , Conducta Alimentaria/fisiología , Interacciones Huésped-Patógeno/fisiología , Animales , Conducta Animal/fisiología , Análisis MultivarianteRESUMEN
BACKGROUND: The extent to which infection versus vaccination has conferred similarly durable severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunity during the Omicron era remains unclear. METHODS: In a cohort of 4496 adults under continued serological surveillance throughout the first year of Omicron-predominant SARS-CoV-2 transmission, we examined incidence of new infection among individuals whose last known antigenic exposure was either recent (<90 days) or remote (≥90 days) infection or vaccination. RESULTS: We adjudicated 2053 new-onset infections occurring between 15 December 2021 through 22 December 2022. In multivariable-adjusted analyses, compared to individuals whose last known exposure was remote vaccination, those with recent vaccination (odds ratio [OR], 0.82 [95% confidence interval {CI}, .73-.93]; P = .002) or recent infection (OR, 0.14 [95% CI, .05-.45]; P = .001) had lower risk for new infection within the subsequent 90-day period. Given a significant age interaction (P = .004), we found that remote infection compared to remote vaccination was associated with significantly greater new infection risk in persons aged ≥60 years (OR, 1.88 [95% CI, 1.13-3.14]; P = .015) with no difference seen in those <60 years (1.03 [95% CI, .69-1.53]; P = .88). CONCLUSIONS: During the initial year of Omicron, prior infection and vaccination both offered protection against new infection. However, remote prior infection was less protective than remote vaccination for individuals aged ≥60 years. In older adults, immunity gained from vaccination appeared more durable than immunity gained from infection.
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Circulating tumour DNA (ctDNA) allows genotyping and minimal residual disease (MRD) detection in lymphomas. Using a next-generation sequencing (NGS) approach (EuroClonality-NDC), we evaluated the clinical and prognostic value of ctDNA in a series of R-CHOP-treated diffuse large B-cell lymphoma (DLBCL) patients at baseline (n = 68) and after two cycles (n = 59), monitored by metabolic imaging (positron emission tomography combined with computed tomography [PET/CT]). A molecular marker was identified in 61/68 (90%) ctDNA samples at diagnosis. Pretreatment high ctDNA levels significantly correlated with elevated lactate dehydrogenase, advanced stage, high-risk International Prognostic Index and a trend to shorter 2-year progression-free survival (PFS). Valuable NGS data after two cycles of treatment were obtained in 44 cases, and 38 achieved major molecular response (MMR; 2.5-log drop in ctDNA). PFS curves displayed statistically significant differences among those achieving MMR versus those not achieving MMR (2-year PFS of 76% vs. 0%, p < 0.001). Similarly, more than 66% reduction in ΔSUVmax by PET/CT identified two subgroups with different prognosis (2-year PFS of 83% vs. 38%; p < 0.001). Combining both approaches MMR and ΔSUVmax reduction, a better stratification was observed (2-year PFS of 84% vs. 17% vs. 0%, p < 0.001). EuroClonality-NDC panel allows the detection of a molecular marker in the ctDNA in 90% of DLBCL. ctDNA reduction at two cycles and its combination with interim PET results improve patient prognosis stratification.
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Protocolos de Quimioterapia Combinada Antineoplásica , ADN Tumoral Circulante , Linfoma de Células B Grandes Difuso , Neoplasia Residual , Humanos , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/diagnóstico , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/sangre , Linfoma de Células B Grandes Difuso/mortalidad , Linfoma de Células B Grandes Difuso/patología , Neoplasia Residual/diagnóstico , Femenino , Masculino , Persona de Mediana Edad , Anciano , Adulto , ADN Tumoral Circulante/sangre , ADN Tumoral Circulante/genética , Biopsia Líquida/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Anciano de 80 o más Años , Tomografía Computarizada por Tomografía de Emisión de Positrones , Rituximab/uso terapéutico , Rituximab/administración & dosificación , Ciclofosfamida/uso terapéutico , Ciclofosfamida/administración & dosificación , Biomarcadores de Tumor/sangre , Vincristina/uso terapéutico , Vincristina/administración & dosificación , Pronóstico , Doxorrubicina/uso terapéutico , Doxorrubicina/administración & dosificación , Secuenciación de Nucleótidos de Alto Rendimiento , Prednisona/uso terapéutico , Prednisona/administración & dosificaciónRESUMEN
OBJECTIVES: Antiviral interventions are required to complement vaccination programmes and reduce the global burden of COVID-19. Prior to initiation of large-scale clinical trials, robust preclinical data to support candidate plausibility are required. This work sought to further investigate the putative antiviral activity of probenecid against SARS-CoV-2. METHODS: Vero E6 cells were preincubated with probenecid, or control media for 2 h before infection (SARS-CoV-2/Human/Liverpool/REMRQ0001/2020). Probenecid or control media was reapplied, plates reincubated and cytopathic activity quantified by spectrophotometry after 48 h. In vitro human airway epithelial cell (HAEC) assays were performed for probenecid against SARS-CoV-2-VoC-B.1.1.7 (hCoV-19/Belgium/rega-12211513/2020; EPI_ISL_791333, 2020-12-21) using an optimized cell model for antiviral testing. Syrian golden hamsters were intranasally inoculated (SARS-CoV-2 Delta B.1.617.2) 24 h prior to treatment with probenecid or vehicle for four twice-daily doses. RESULTS: No observable antiviral activity for probenecid was evident in Vero E6 or HAEC assays. No reduction in total or subgenomic RNA was observed in terminal lung samples (P > 0.05) from hamsters. Body weight of uninfected hamsters remained stable whereas both probenecid- and vehicle-treated infected hamsters lost body weight (P > 0.5). CONCLUSIONS: These data do not support probenecid as a SARS-CoV-2 antiviral drug.
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Pulmón , Probenecid , Cricetinae , Animales , Humanos , Mesocricetus , Probenecid/farmacología , Peso Corporal , Antivirales/farmacologíaRESUMEN
BACKGROUND: Internet-based health education is increasingly vital in patient care. However, the readability of online information often exceeds the average reading level of the US population, limiting accessibility and comprehension. This study investigates the use of chatbot artificial intelligence to improve the readability of cancer-related patient-facing content. METHODS: We used ChatGPT 4.0 to rewrite content about breast, colon, lung, prostate, and pancreas cancer across 34 websites associated with NCCN Member Institutions. Readability was analyzed using Fry Readability Score, Flesch-Kincaid Grade Level, Gunning Fog Index, and Simple Measure of Gobbledygook. The primary outcome was the mean readability score for the original and artificial intelligence (AI)-generated content. As secondary outcomes, we assessed the accuracy, similarity, and quality using F1 scores, cosine similarity scores, and section 2 of the DISCERN instrument, respectively. RESULTS: The mean readability level across the 34 websites was equivalent to a university freshman level (grade 13±1.5). However, after ChatGPT's intervention, the AI-generated outputs had a mean readability score equivalent to a high school freshman education level (grade 9±0.8). The overall F1 score for the rewritten content was 0.87, the precision score was 0.934, and the recall score was 0.814. Compared with their original counterparts, the AI-rewritten content had a cosine similarity score of 0.915 (95% CI, 0.908-0.922). The improved readability was attributed to simpler words and shorter sentences. The mean DISCERN score of the random sample of AI-generated content was equivalent to "good" (28.5±5), with no significant differences compared with their original counterparts. CONCLUSIONS: Our study demonstrates the potential of AI chatbots to improve the readability of patient-facing content while maintaining content quality. The decrease in requisite literacy after AI revision emphasizes the potential of this technology to reduce health care disparities caused by a mismatch between educational resources available to a patient and their health literacy.
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Inteligencia Artificial , Comprensión , Alfabetización en Salud , Internet , Neoplasias , Humanos , Alfabetización en Salud/métodos , Alfabetización en Salud/normas , Educación del Paciente como Asunto/métodos , Educación del Paciente como Asunto/normas , Información de Salud al Consumidor/normas , Información de Salud al Consumidor/métodosRESUMEN
The main protease (Mpro) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) plays an important role in viral replication and transcription and received great attention as a vital target for drug/peptide development. Therapeutic agents such as small-molecule drugs or peptides that interact with the Cys-His present in the catalytic site of Mpro are an efficient way to inhibit the protease. Although several emergency-approved vaccines showed good efficacy and drastically dropped the infection rate, evolving variants are still infecting and killing millions of people globally. While a small-molecule drug (Paxlovid) received emergency approval, small-molecule drugs have low target specificity and higher toxicity. Besides small-molecule drugs, peptide therapeutics are thus gaining increasing popularity as they are easy to synthesize and highly selective and have limited side effects. In this study, we investigated the therapeutic value of 67 peptides targeting Mpro using molecular docking. Subsequently, molecular dynamics (MD) simulations were implemented on eight protein-peptide complexes to obtain molecular-level information on the interaction between these peptides and the Mpro active site, which revealed that temporin L, indolicidin, and lymphocytic choriomeningitis virus (LCMV) GP1 are the best candidates in terms of stability, interaction, and structural compactness. These peptides were synthesized using the solid-phase peptide synthesis protocol, purified by reversed-phase high-performance liquid chromatography (RP-HPLC), and authenticated by mass spectrometry (MS). The in vitro fluorometric Mpro activity assay was used to validate the computational results, where temporin L and indolicidin were observed to be very active against SARS-CoV-2 Mpro with IC50 values of 38.80 and 87.23 µM, respectively. A liquid chromatography-MS (LC-MS) assay was developed, and the IC50 value of temporin L was measured at 23.8 µM. The solution-state nuclear magnetic resonance (NMR) structure of temporin L was determined in the absence of sodium dodecyl sulfate (SDS) micelles and was compared to previous temporin structures. This combined investigation provides critical insights and assists us to further develop peptide inhibitors of SARS-CoV-2 Mpro through structural guided investigation.
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COVID-19 , Péptido Hidrolasas , Humanos , SARS-CoV-2 , Simulación del Acoplamiento Molecular , Antivirales/farmacología , Inhibidores de Proteasas/farmacología , Simulación de Dinámica MolecularRESUMEN
BACKGROUND: Increasing evidence links higher air pollution exposures to increased risk of cognitive impairment. While midlife risk factors are often most strongly linked to dementia risk, few studies have considered associations between midlife roadway proximity or ambient air pollution exposure and incident dementia decades later, in late life. OBJECTIVES: Our objective was to determine if midlife exposures to ambient air pollution or roadway proximity are associated with increased risk of dementia in the Atherosclerosis Risk in Communities (ARIC) study over up to 29 years of follow-up. METHODS: Our eligible sample included Black and White ARIC participants without dementia at Visit 2 (1990-1992). Participants were followed through Visit 7 (2018-2019), with dementia status and onset date defined based on formal dementia ascertainment at study visits, informant interviews, and surveillance efforts. We used adjusted Weibull survival models to assess the associations of midlife ambient air pollution and road proximity with incident dementia. RESULTS: The median age at baseline (1990-1992, Visit 2) of the 12,700 eligible ARIC participants was 57.0 years; 56.0% were female, 24.2% were Black, and 78.9% had at least a high school education. Over up to 29 years of follow-up, 2511 (19.8%) persons developed dementia. No associations were found between ambient air pollutants and proximity to major roadways with risk of incident dementia. In exploratory analyses, living closer to roadways in midlife increased dementia risk in individuals younger at baseline and those without midlife hypertension, and there was evidence of increased risk of dementia with increased midlife exposure to NOx, several PM2.5 components, and trace metals among those with diabetes in midlife. CONCLUSIONS: Midlife exposure to ambient air pollution and midlife roadway proximity was not associated with dementia risk over decades of follow-up. Further investigation to explore potential for greater susceptibility among specific subgroups identified here is needed.
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Contaminantes Atmosféricos , Contaminación del Aire , Demencia , Exposición a Riesgos Ambientales , Humanos , Persona de Mediana Edad , Demencia/epidemiología , Demencia/inducido químicamente , Demencia/etiología , Femenino , Masculino , Exposición a Riesgos Ambientales/efectos adversos , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Anciano , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/efectos adversos , Incidencia , Factores de Riesgo , Aterosclerosis/epidemiología , Aterosclerosis/etiología , Material Particulado/análisis , Material Particulado/efectos adversos , Emisiones de Vehículos/análisisRESUMEN
BACKGROUND: Reported associations between particulate matter with aerodynamic diameter ≤2.5 µm (PM2.5) and cognitive outcomes remain mixed. Differences in exposure estimation method may contribute to this heterogeneity. OBJECTIVES: To assess agreement between PM2.5 exposure concentrations across 11 exposure estimation methods and to compare resulting associations between PM2.5 and cognitive or MRI outcomes. METHODS: We used Visit 5 (2011-2013) cognitive testing and brain MRI data from the Atherosclerosis Risk in Communities (ARIC) Study. We derived address-linked average 2000-2007 PM2.5 exposure concentrations in areas immediately surrounding the four ARIC recruitment sites (Forsyth County, NC; Jackson, MS; suburbs of Minneapolis, MN; Washington County, MD) using 11 estimation methods. We assessed agreement between method-specific PM2.5 concentrations using descriptive statistics and plots, overall and by site. We used adjusted linear regression to estimate associations of method-specific PM2.5 exposure estimates with cognitive scores (n = 4678) and MRI outcomes (n = 1518) stratified by study site and combined site-specific estimates using meta-analyses to derive overall estimates. We explored the potential impact of unmeasured confounding by spatially patterned factors. RESULTS: Exposure estimates from most methods had high agreement across sites, but low agreement within sites. Within-site exposure variation was limited for some methods. Consistently null findings for the PM2.5-cognitive outcome associations regardless of method precluded empirical conclusions about the potential impact of method on study findings in contexts where positive associations are observed. Not accounting for study site led to consistent, adverse associations, regardless of exposure estimation method, suggesting the potential for substantial bias due to residual confounding by spatially patterned factors. DISCUSSION: PM2.5 estimation methods agreed across sites but not within sites. Choice of estimation method may impact findings when participants are concentrated in small geographic areas. Understanding unmeasured confounding by factors that are spatially patterned may be particularly important in studies of air pollution and cognitive or brain health.
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Contaminantes Atmosféricos , Encéfalo , Cognición , Exposición a Riesgos Ambientales , Imagen por Resonancia Magnética , Material Particulado , Material Particulado/análisis , Humanos , Masculino , Persona de Mediana Edad , Femenino , Cognición/efectos de los fármacos , Contaminantes Atmosféricos/análisis , Encéfalo/diagnóstico por imagen , Encéfalo/efectos de los fármacos , Anciano , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisisRESUMEN
BACKGROUND: Heterogeneity in ageing rates drives the need for research into lifestyle secrets of successful agers. Biological age, predicted by epigenetic clocks, has been shown to be a more reliable measure of ageing than chronological age. Dietary habits are known to affect the ageing process. However, much remains to be learnt about specific dietary habits that may directly affect the biological process of ageing. OBJECTIVE: To identify food groups that are directly related to biological ageing, using Copula Graphical Models. METHODS: We performed a preregistered analysis of 3,990 postmenopausal women from the Women's Health Initiative, based in North America. Biological age acceleration was calculated by the epigenetic clock PhenoAge using whole-blood DNA methylation. Copula Graphical Modelling, a powerful data-driven exploratory tool, was used to examine relations between food groups and biological ageing whilst adjusting for an extensive amount of confounders. Two food group-age acceleration networks were established: one based on the MyPyramid food grouping system and another based on item-level food group data. RESULTS: Intake of eggs, organ meat, sausages, cheese, legumes, starchy vegetables, added sugar and lunch meat was associated with biological age acceleration, whereas intake of peaches/nectarines/plums, poultry, nuts, discretionary oil and solid fat was associated with decelerated ageing. CONCLUSION: We identified several associations between specific food groups and biological ageing. These findings pave the way for subsequent studies to ascertain causality and magnitude of these relationships, thereby improving the understanding of biological mechanisms underlying the interplay between food groups and biological ageing.
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Envejecimiento , Metilación de ADN , Conducta Alimentaria , Humanos , Femenino , Anciano , Persona de Mediana Edad , Factores de Edad , Epigénesis Genética , Dieta/estadística & datos numéricos , PosmenopausiaRESUMEN
One of the most reactive intermediates for oxidative reactions is the oxyl radical, an electron-deficient oxygen atom. The discovery of a new vibration upon photoexcitation of the oxygen evolution catalysis detected the oxyl radical at the SrTiO3 surface. The vibration was assigned to a motion of the sub-surface oxygen underneath the titanium oxyl (Ti-Oâ-) created upon hole transfer to (or electron extraction from) a hydroxylated surface site. Evidence for such an interfacial mode is derived from its spectral shape, which exhibited a Fano resonance-a coupling of a sharp normal mode to continuum excitations. Here, this Fano resonance is utilized to derive precise formation kinetics of the oxyl radical and its associated potential energy surface (PES). From the Fano lineshape, the formation kinetics are obtained from the anti-resonance (the kinetics of the coupling factor), the resonance (the kinetics of the coupled continuum excitations), and the frequency integrated spectrum (the kinetics of the normal mode's cross-section). All three perspectives yield logistic function growth with a half-rise of 2.3 ± 0.3 ps and a time constant of 0.48 ± 0.09 ps. A non-equilibrium transient associated with photoexcitation is separated from the rise of the equilibrated PES. The logistic function characterizes the oxyl coverage at the very initial stages (t â¼ 0) to have an exponential growth rate that quickly decreases toward zero as a limiting coverage is reached. Such time-dependent reaction kinetics identify a dynamic activation barrier associated with the formation of a PES and quantify it for oxyl radical coverage.
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BACKGROUND: Ambient air pollution, including traffic-related air pollution (TRAP), increases cardiovascular disease risk, possibly through vascular alterations. Limited information exists about in-vehicle TRAP exposure and vascular changes. OBJECTIVE: To determine via particle filtration the effect of on-roadway TRAP exposure on blood pressure and retinal vasculature. DESIGN: Randomized crossover trial. (ClinicalTrials.gov: NCT05454930). SETTING: In-vehicle scripted commutes driven through traffic in Seattle, Washington, during 2014 to 2016. PARTICIPANTS: Normotensive persons aged 22 to 45 years (n = 16). INTERVENTION: On 2 days, on-road air was entrained into the vehicle. On another day, the vehicle was equipped with high-efficiency particulate air (HEPA) filtration. Participants were blinded to the exposure and were randomly assigned to the sequence. MEASUREMENTS: Fourteen 3-minute periods of blood pressure were recorded before, during, and up to 24 hours after a drive. Image-based central retinal arteriolar equivalents (CRAEs) were measured before and after. Brachial artery diameter and gene expression were also measured and will be reported separately. RESULTS: Mean age was 29.7 years, predrive systolic blood pressure was 122.7 mm Hg, predrive diastolic blood pressure was 70.8 mm Hg, and drive duration was 122.3 minutes (IQR, 4 minutes). Filtration reduced particle count by 86%. Among persons with complete data (n = 13), at 1 hour, mean diastolic blood pressure, adjusted for predrive levels, order, and carryover, was 4.7 mm Hg higher (95% CI, 0.9 to 8.4 mm Hg) for unfiltered drives compared with filtered drives, and mean adjusted systolic blood pressure was 4.5 mm Hg higher (CI, -1.2 to 10.2 mm Hg). At 24 hours, adjusted mean diastolic blood pressure (unfiltered) was 3.8 mm Hg higher (CI, 0.02 to 7.5 mm Hg) and adjusted mean systolic blood pressure was 1.1 mm Hg higher (CI, -4.6 to 6.8 mm Hg). Adjusted mean CRAE (unfiltered) was 2.7 µm wider (CI, -1.5 to 6.8 µm). LIMITATIONS: Imprecise estimates due to small sample size; seasonal imbalance by exposure order. CONCLUSION: Filtration of TRAP may mitigate its adverse effects on blood pressure rapidly and at 24 hours. Validation is required in larger samples and different settings. PRIMARY FUNDING SOURCE: U.S. Environmental Protection Agency and National Institutes of Health.
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Contaminantes Atmosféricos , Contaminación del Aire , Humanos , Adulto , Presión Sanguínea , Contaminantes Atmosféricos/efectos adversos , Material Particulado/efectos adversos , Material Particulado/análisis , Estudios Cruzados , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisisRESUMEN
Eggs of oviparous reptiles are ideal models for studying evolutionary patterns of embryonic metabolism since they allow tracking of energy allocation during development. Analyzing oxygen consumption of whole eggs throughout development indicates three patterns among reptiles. Embryos initially grow and consume oxygen exponentially, but oxygen consumption slows, or drops before hatching in some species. Turtles, crocodilians, and most lizards follow curves with initial exponential increases followed by declines, whereas embryonic snakes that have been studied exhibit a consistently exponential pattern. This study measured oxygen consumption of corn snake, Pantherophis guttatus, embryos to determine if this species also exhibits an exponential increase in oxygen consumption. Individual eggs, sampled weekly from oviposition to hatching, were placed in respirometry chambers for 24-h during which oxygen consumption was recorded. Embryos were staged and carcasses and yolk were weighed separately. Results indicate steady inclines in oxygen consumption during early stages of development, with a rapid increase prior to hatching. The findings support the hypothesis that embryonic oxygen consumption of snakes differs from most other non-avian reptiles. Total energy required for development was determined based on calorimetry of initial yolk compared to hatchlings and residual yolk and by integration of the area under the curve plotting oxygen consumption versus age of embryos. The cost of development estimates based on these two methods were 6.4 and 10.0 kJ, respectively. Our results emphasize the unique physiological aspects of snake embryogenesis and illustrate how the study of physiological characteristics can contribute to the broader understanding of reptilian evolution.
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Colubridae , Oviparidad , Zea mays , Femenino , Animales , Oviparidad/fisiología , Embrión no Mamífero/fisiología , SerpientesRESUMEN
Melioidosis, caused by the environmental gram-negative bacterium Burkholderia pseudomallei, usually develops in adults with predisposing conditions and in Australia more commonly occurs during the monsoonal wet season. We report an outbreak of 7 cases of melioidosis in immunocompetent children in Australia. All the children had participated in a single-day sporting event during the dry season in a tropical region of Australia, and all had limited cutaneous disease. All case-patients had an adverse reaction to oral trimethoprim/sulfamethoxazole treatment, necessitating its discontinuation. We describe the clinical features, environmental sampling, genomic epidemiologic investigation, and public health response to the outbreak. Management of this outbreak shows the potential benefits of making melioidosis a notifiable disease. The approach used could also be used as a framework for similar outbreaks in the future.