Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 224
Filtrar
Más filtros

Intervalo de año de publicación
1.
Proc Natl Acad Sci U S A ; 121(3): e2317668121, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38194455

RESUMEN

Orofacial clefts of the lip and palate are widely recognized to result from complex gene-environment interactions, but inadequate understanding of environmental risk factors has stymied development of prevention strategies. We interrogated the role of DNA methylation, an environmentally malleable epigenetic mechanism, in orofacial development. Expression of the key DNA methyltransferase enzyme DNMT1 was detected throughout palate morphogenesis in the epithelium and underlying cranial neural crest cell (cNCC) mesenchyme, a highly proliferative multipotent stem cell population that forms orofacial connective tissue. Genetic and pharmacologic manipulations of DNMT activity were then applied to define the tissue- and timing-dependent requirement of DNA methylation in orofacial development. cNCC-specific Dnmt1 inactivation targeting initial palate outgrowth resulted in OFCs, while later targeting during palatal shelf elevation and elongation did not. Conditional Dnmt1 deletion reduced cNCC proliferation and subsequent differentiation trajectory, resulting in attenuated outgrowth of the palatal shelves and altered development of cNCC-derived skeletal elements. Finally, we found that the cellular mechanisms of cleft pathogenesis observed in vivo can be recapitulated by pharmacologically reducing DNA methylation in multipotent cNCCs cultured in vitro. These findings demonstrate that DNA methylation is a crucial epigenetic regulator of cNCC biology, define a critical period of development in which its disruption directly causes OFCs, and provide opportunities to identify environmental influences that contribute to OFC risk.


Asunto(s)
Labio Leporino , Fisura del Paladar , Animales , Ratones , Labio Leporino/genética , Metilación de ADN , Fisura del Paladar/genética , Cresta Neural , Metilasas de Modificación del ADN , Proliferación Celular
2.
J Hepatol ; 80(4): 543-552, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38092157

RESUMEN

BACKGROUND & AIMS: Chronic liver disease (CLD) causes 1.8% of all deaths in Europe, many of them from liver cancer. We estimated the impact of several policy interventions in France, the Netherlands, and Romania. METHODS: We used a validated microsimulation model to assess seven different policy scenarios in 2022-2030: a minimum unit price (MUP) of alcohol of €0.70 or €1, a volumetric alcohol tax, a sugar-sweetened beverage (SSB) tax, food marketing restrictions, plus two different combinations of these policies compared against current policies (the 'inaction' scenario). RESULTS: All policies reduced the burden of CLD and liver cancer. The largest impact was observed for a MUP of €1, which by 2030 would reduce the cumulative incidence of CLD by between 7.1% to 7.3% in France, the Netherlands, and Romania compared with inaction. For liver cancer, the corresponding reductions in cumulative incidence were between 4.8% to 5.8%. Implementing a package containing a MUP of €0.70, a volumetric alcohol tax, and an SSB tax would reduce the cumulative incidence of CLD by between 4.29% to 4.71% and of liver cancer by between 3.47% to 3.95% in France, the Netherlands, and Romania. The total predicted reduction in healthcare costs by 2030 was greatest with the €1 MUP scenario, with a reduction for liver cancer costs of €8.18M and €612.49M in the Netherlands and France, respectively. CONCLUSIONS: Policy measures tackling primary risk factors for CLD and liver cancer, such as the implementation of a MUP of €1 and/or a MUP of €0.70 plus SSB tax could markedly reduce the number of Europeans with CLD or liver cancer. IMPACT AND IMPLICATIONS: Policymakers must be aware that alcohol and obesity are the two leading risk factors for chronic liver disease and liver cancer in Europe and both are expected to increase in the future if no policy interventions are made. This study assessed the potential of different public health policy measures to mitigate the impact of alcohol consumption and obesity on the general population in three European countries: France, the Netherlands, and Romania. The findings support introducing a €1 minimum unit price for alcohol to reduce the burden of chronic liver disease. In addition, the study shows the importance of targeting multiple drivers of alcohol consumption and obesogenic products simultaneously via a harmonized fiscal policy framework, to complement efforts being made within health systems. These findings should encourage policymakers to introduce such policy measures across Europe to reduce the burden of liver disease. The modeling methods used in this study can assist in structuring similar modeling in other regions to expand on this study's findings.


Asunto(s)
Enfermedades del Sistema Digestivo , Neoplasias Hepáticas , Humanos , Impuestos , Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/epidemiología , Consumo de Bebidas Alcohólicas/prevención & control , Obesidad/epidemiología , Obesidad/prevención & control , Etanol , Políticas , Costos de la Atención en Salud , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/prevención & control
3.
Exp Dermatol ; 33(5): e15099, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38794814

RESUMEN

Suitable human models for the development and characterization of topical compounds for inflammatory skin diseases such as atopic dermatitis are not readily available to date. We describe here the development of a translational model involving healthy human skin mimicking major aspects of AD and its application for the characterization of topical Janus kinase inhibitors. Full thickness human abdominal skin obtained from plastic surgery stimulated in vitro with IL4 and IL13 shows molecular features of AD. This is evidenced by STAT6 phosphorylation assessed by immunohistochemistry and analysis of skin lysates. Broad transcriptome changes assessed by AmpliSeq followed by gene set variation analysis showed a consistent upregulation of gene signatures characterizing AD in this model. Topical application of experimental formulations of compounds targeting the JAK pathway to full thickness skin normalizes the molecular features of AD induced by IL4 and IL13 stimulation. The inhibitory effects of topical JAK inhibitors on molecular features of AD are supported by pharmacokinetic analysis. The model described here is suited for the characterization of topical compounds for AD and has the potential to be extended to other inflammatory skin diseases and pathophysiological pathways.


Asunto(s)
Dermatitis Atópica , Inhibidores de las Cinasas Janus , Piel , Humanos , Dermatitis Atópica/tratamiento farmacológico , Piel/metabolismo , Piel/efectos de los fármacos , Inhibidores de las Cinasas Janus/farmacología , Factor de Transcripción STAT6/metabolismo , Interleucina-4/metabolismo , Interleucina-13/metabolismo , Fosforilación , Transcriptoma , Modelos Biológicos , Pirimidinas/farmacología , Administración Tópica , Piperidinas
4.
Psychol Sci ; 35(3): 304-311, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38386358

RESUMEN

There is a long-standing debate in cognitive science surrounding the source of commonalities among languages of the world. Indeed, there are many potential explanations for such commonalities-accidents of history, common processes of language change, memory limitations, constraints on linguistic representations, and so on. Recent research has used psycholinguistic experiments to provide empirical evidence linking common linguistic patterns to specific features of human cognition, but these experiments tend to use English speakers, who in many cases have direct experience with the common patterns of interest. Here we highlight the importance of testing populations whose languages go against cross-linguistic trends. We investigate whether adult monolingual speakers of Kîîtharaka, which has an unusual way of ordering words, mirror the word-order preferences of English speakers. We find that they do, supporting the hypothesis that universal cognitive representations play a role in shaping word order.


Asunto(s)
Lenguaje , Lingüística , Adulto , Humanos , Psicolingüística , Desarrollo del Lenguaje , Cognición
5.
Angew Chem Int Ed Engl ; 63(13): e202319579, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38291002

RESUMEN

A cascade of three enzymes, E1-E2-E3, is responsible for transferring ubiquitin to target proteins, which controls many different aspects of cellular signaling. The role of the E2 has been largely overlooked, despite influencing substrate identity, chain multiplicity, and topology. Here we report a method-targeted charging of ubiquitin to E2 (tCUbE)-that can track a tagged ubiquitin through its entire enzymatic cascade in living mammalian cells. We use this approach to reveal new targets whose ubiquitination depends on UbcH5a E2 activity. We demonstrate that tCUbE can be broadly applied to multiple E2s and in different human cell lines. tCUbE is uniquely suited to examine E2-E3-substrate cascades of interest and/or piece together previously unidentified cascades, thereby illuminating entire branches of the UPS and providing critical insight that will be useful for identifying new therapeutic targets in the UPS.


Asunto(s)
Enzimas Ubiquitina-Conjugadoras , Ubiquitina , Animales , Humanos , Enzimas Ubiquitina-Conjugadoras/metabolismo , Ubiquitinación , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Mamíferos/metabolismo
6.
Eur J Pediatr ; 182(2): 543-554, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36243780

RESUMEN

To assess and describe the aetiology and management of febrile illness in children with primary or acquired immunodeficiency at high risk of serious bacterial infection, as seen in emergency departments in tertiary hospitals. Prospective data on demographics, presenting features, investigations, microbiology, management, and outcome of patients within the 'Biomarker Validation in HR patients' database in PERFORM, were analysed. Immunocompromised children (< 18 years old) presented to fifteen European hospitals in nine countries, and one Gambian hospital, with fever or suspected infection and clinical indication for blood investigations. Febrile episodes were assigned clinical phenotypes using the validated PERFORM algorithm. Logistic regression was used to assess the effect size of predictive features of proven/presumed bacterial or viral infection. A total of 599 episodes in 482 children were analysed. Seventy-eight episodes (13.0%) were definite bacterial, 67 episodes probable bacterial (11.2%), and 29 bacterial syndrome (4.8%). Fifty-five were definite viral (9.2%), 49 probable viral (8.2%), and 23 viral syndrome (3.8%). One hundred ninety were unknown bacterial or viral infections (31.7%), and 108 had inflammatory or other non-infectious causes of fever (18.1%). Predictive features of proven/presumed bacterial infection were ill appearance (OR 3.1 (95% CI 2.1-4.6)) and HIV (OR 10.4 (95% CI 2.0-54.4)). Ill appearance reduced the odds of having a proven/presumed viral infection (OR 0.5 (95% CI 0.3-0.9)). A total of 82.1% had new empirical antibiotics started on admission (N = 492); 94.3% proven/presumed bacterial (N = 164), 66.1% proven/presumed viral (N = 84), and 93.2% unknown bacterial or viral infections (N = 177). Mortality was 1.9% (N = 11) and 87.1% made full recovery (N = 522).   Conclusion: The aetiology of febrile illness in immunocompromised children is diverse. In one-third of cases, no cause for the fever will be identified. Justification for standard intravenous antibiotic treatment for every febrile immunocompromised child is debatable, yet effective. Better clinical decision-making tools and new biomarkers are needed for this population. What is Known: • Immunosuppressed children are at high risk for morbidity and mortality of serious bacterial and viral infection, but often present with fever as only clinical symptom. • Current diagnostic measures in this group are not specific to rule out bacterial infection, and positivity rates of microbiological cultures are low. What is New: • Febrile illness and infectious complications remain a significant cause of mortality and morbidity in HR children, yet management is effective. • The aetiology of febrile illness in immunocompromised children is diverse, and development of pathways for early discharge or cessation of intravenous antibiotics is debatable, and requires better clinical decision-making tools and biomarkers.


Asunto(s)
Infecciones Bacterianas , Virosis , Niño , Humanos , Estudios Prospectivos , Infecciones Bacterianas/complicaciones , Infecciones Bacterianas/diagnóstico , Infecciones Bacterianas/epidemiología , Fiebre/diagnóstico , Fiebre/etiología , Fiebre/tratamiento farmacológico , Antibacterianos/uso terapéutico , Virosis/complicaciones , Virosis/diagnóstico , Virosis/tratamiento farmacológico , Biomarcadores
7.
Eur J Orthop Surg Traumatol ; 33(1): 99-105, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34807327

RESUMEN

PURPOSE: Talar neck and body fractures are uncommon injuries that are challenging to manage with high reported complication rates, including post-traumatic arthritis, avascular necrosis, and poor functional outcomes. The aim of this study was to assess the complication rates for patients with talus fractures across three major trauma centres (MTCs) in England. METHODS: A retrospective analysis was performed of prospectively collected trauma databases. Data were collected from three English MTCs. Patients with talar neck and/or body fractures sustained between August 2015 and August 2019 were identified and their clinical course reviewed radiologically and clinically. Isolated process fractures, osteochondral defects and paediatric patients were excluded. Patients were analysed by fracture type and for definitive treatment method with separation into non-operative and operative management groups. Procedure type was identified in the operative group. Superficial infection, deep infection, non-union, avascular necrosis, post-traumatic arthritis and removal of metalwork rates were analysed. RESULTS: Eighty-five patients with talar neck and/or body fractures were included. Seventy-five patients received operative management, 10 non-operative. The overall AVN rate was 5.9% (five patients), overall post-traumatic arthritis rate was 18.8% (16 patients), deep infection rate 1.2% (one patient), non-union rate 4.7% (four patients). Removal of metalwork rate was 9.4% (eight patients). CONCLUSION: Our reported outcomes and complication rates are generally lower than those previously described. This may be a result of improved techniques, a higher frequency of open reduction with direct visualisation or by surgery occurring in centralised specialist centres.


Asunto(s)
Artritis , Fracturas Óseas , Osteonecrosis , Astrágalo , Humanos , Niño , Estudios Retrospectivos , Fijación Interna de Fracturas/efectos adversos , Fijación Interna de Fracturas/métodos , Astrágalo/diagnóstico por imagen , Astrágalo/cirugía , Fracturas Óseas/complicaciones , Fracturas Óseas/cirugía , Osteonecrosis/etiología
8.
Lancet Oncol ; 23(10): 1308-1320, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36113498

RESUMEN

BACKGROUND: Localised prostate cancer is commonly treated with external beam radiotherapy and moderate hypofractionation is non-inferior to longer schedules. Stereotactic body radiotherapy (SBRT) allows shorter treatment courses without impacting acute toxicity. We report 2-year toxicity findings from PACE-B, a randomised trial of conventionally fractionated or moderately hypofractionated radiotherapy versus SBRT. METHODS: PACE is an open-label, multicohort, randomised, controlled, phase 3 trial conducted at 35 hospitals in the UK, Ireland, and Canada. In PACE-B, men aged 18 years and older with a WHO performance status 0-2 and low-risk or intermediate-risk histologically-confirmed prostate adenocarcinoma (Gleason 4 + 3 excluded) were randomly allocated (1:1) by computerised central randomisation with permuted blocks (size four and six), stratified by centre and risk group to control radiotherapy (CRT; 78 Gy in 39 fractions over 7·8 weeks or, following protocol amendment on March 24, 2016, 62 Gy in 20 fractions over 4 weeks) or SBRT (36·25 Gy in five fractions over 1-2 weeks). Androgen deprivation was not permitted. Co-primary outcomes for this toxicity analysis were Radiation Therapy Oncology Group (RTOG) grade 2 or worse gastrointestinal and genitourinary toxicity at 24 months after radiotherapy. Analysis was by treatment received and included all patients with at least one fraction of study treatment assessed for late toxicity. Recruitment is complete. Follow-up for oncological outcomes continues. The trial is registered with ClinicalTrials.gov, NCT01584258. FINDINGS: We enrolled and randomly assigned 874 men between Aug 7, 2012, and Jan 4, 2018 (441 to CRT and 433 to SBRT). In this analysis, 430 patients were analysed in the CRT group and 414 in the SBRT group; a total of 844 (97%) of 874 randomly assigned patients. At 24 months, RTOG grade 2 or worse genitourinary toxicity was seen in eight (2%) of 381 participants assigned to CRT and 13 (3%) of 384 participants assigned to SBRT (absolute difference 1·3% [95% CI -1·3 to 4·0]; p=0·39); RTOG grade 2 or worse gastrointestinal toxicity was seen in 11 (3%) of 382 participants in the CRT group versus six (2%) of 384 participants in the SBRT group (absolute difference -1·3% [95% CI -3·9 to 1·1]; p=0·32). No serious adverse events (defined as RTOG grade 4 or worse) or treatment-related deaths were reported within the analysis timeframe. INTERPRETATION: In the PACE-B trial, 2-year RTOG toxicity rates were similar for five fraction SBRT and conventional schedules of radiotherapy. Prostate SBRT was found to be safe and associated with low rates of side-effects. Biochemical outcomes are awaited. FUNDING: Accuray.


Asunto(s)
Neoplasias de la Próstata , Radiocirugia , Radioterapia de Intensidad Modulada , Andrógenos , Humanos , Masculino , Neoplasias de la Próstata/patología , Radiocirugia/efectos adversos , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/métodos , Resultado del Tratamiento
9.
Hepatology ; 74(4): 1766-1781, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33991110

RESUMEN

BACKGROUND AND AIMS: Therapeutic strategies against HBV focus, among others, on the activation of the immune system to enable the infected host to eliminate HBV. Hypoxia-inducible factor 1 alpha (HIF1α) stabilization has been associated with impaired immune responses. HBV pathogenesis triggers chronic hepatitis-related scaring, leading inter alia to modulation of liver oxygenation and transient immune activation, both factors playing a role in HIF1α stabilization. APPROACH AND RESULTS: We addressed whether HIF1α interferes with immune-mediated induction of the cytidine deaminase, apolipoprotein B mRNA editing enzyme catalytic subunit 3B (APOBEC3B; A3B), and subsequent covalently closed circular DNA (cccDNA) decay. Liver biopsies of chronic HBV (CHB) patients were analyzed by immunohistochemistry and in situ hybridization. The effect of HIF1α induction/stabilization on differentiated HepaRG or mice ± HBV ± LTßR-agonist (BS1) was assessed in vitro and in vivo. Induction of A3B and subsequent effects were analyzed by RT-qPCR, immunoblotting, chromatin immunoprecipitation, immunocytochemistry, and mass spectrometry. Analyzing CHB highlighted that areas with high HIF1α levels and low A3B expression correlated with high HBcAg, potentially representing a reservoir for HBV survival in immune-active patients. In vitro, HIF1α stabilization strongly impaired A3B expression and anti-HBV effect. Interestingly, HIF1α knockdown was sufficient to rescue the inhibition of A3B up-regulation and -mediated antiviral effects, whereas HIF2α knockdown had no effect. HIF1α stabilization decreased the level of v-rel reticuloendotheliosis viral oncogene homolog B protein, but not its mRNA, which was confirmed in vivo. Noteworthy, this function of HIF1α was independent of its partner, aryl hydrocarbon receptor nuclear translocator. CONCLUSIONS: In conclusion, inhibiting HIF1α expression or stabilization represents an anti-HBV strategy in the context of immune-mediated A3B induction. High HIF1α, mediated by hypoxia or inflammation, offers a reservoir for HBV survival in vivo and should be considered as a restricting factor in the development of immune therapies.


Asunto(s)
Citidina Desaminasa/genética , Hepatitis B Crónica/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Hígado/metabolismo , Antígenos de Histocompatibilidad Menor/genética , Factor de Transcripción ReIB/genética , Aminoácidos Dicarboxílicos/farmacología , Animales , Línea Celular , Citidina Desaminasa/metabolismo , ADN Circular/metabolismo , Regulación hacia Abajo , Técnicas de Silenciamiento del Gen , Virus de la Hepatitis B , Hepatitis B Crónica/metabolismo , Hepatitis B Crónica/virología , Humanos , Hipoxia/genética , Hipoxia/metabolismo , Receptor beta de Linfotoxina/agonistas , Ratones , Viabilidad Microbiana , Antígenos de Histocompatibilidad Menor/metabolismo , ARN Mensajero/metabolismo , Factor de Transcripción ReIB/efectos de los fármacos , Factor de Transcripción ReIB/metabolismo
10.
Int J Mol Sci ; 23(3)2022 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-35163131

RESUMEN

The pleiotropic function of 3',5'-cyclic adenosine monophosphate (cAMP)-dependent pathways in health and disease led to the development of pharmacological phosphodiesterase inhibitors (PDE-I) to attenuate cAMP degradation. While there are many isotypes of PDE, a predominant role of PDE4 is to regulate fundamental functions, including endothelial and epithelial barrier stability, modulation of inflammatory responses and cognitive and/or mood functions. This makes the use of PDE4-I an interesting tool for various therapeutic approaches. However, due to the presence of PDE4 in many tissues, there is a significant danger for serious side effects. Based on this, the aim of this review is to provide a comprehensive overview of the approaches and effects of PDE4-I for different therapeutic applications. In summary, despite many obstacles to use of PDE4-I for different therapeutic approaches, the current data warrant future research to utilize the therapeutic potential of phosphodiesterase 4 inhibition.


Asunto(s)
3',5'-AMP Cíclico Fosfodiesterasas/antagonistas & inhibidores , Disfunción Cognitiva/tratamiento farmacológico , AMP Cíclico/metabolismo , Inflamación/tratamiento farmacológico , Trastornos del Humor/tratamiento farmacológico , Inhibidores de Fosfodiesterasa 4/farmacología , Animales , Disfunción Cognitiva/enzimología , Humanos , Inflamación/enzimología , Trastornos del Humor/enzimología
11.
Int J Mol Sci ; 23(5)2022 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35269551

RESUMEN

It is well known that certain non B-DNA structures, including G-quadruplexes, are key elements that can regulate gene expression. Here, we explore the theory that DNA modifications, such as methylation of cytosine, could act as a dynamic switch by promoting or alleviating the structural formation of G-quadruplex structures in DNA or RNA. The interaction between epigenetic DNA modifications, G4 formation, and the 3D architecture of the genome is a complex and developing area of research. Although there is growing evidence for such interactions, a great deal still remains to be discovered. In vivo, the potential effect that cytosine methylation may have on the formation of DNA structures has remained largely unresearched, despite this being a potential mechanism through which epigenetic factors could regulate gene activity. Such interactions could represent novel mechanisms for important biological functions, including altering nucleosome positioning or regulation of gene expression. Furthermore, promotion of strand-specific G-quadruplex formation in differentially methylated genes could have a dynamic role in directing X-inactivation or the control of imprinting, and would be a worthwhile focus for future research.


Asunto(s)
Citosina/metabolismo , ADN/química , Animales , Metilación de ADN , Epigénesis Genética , G-Cuádruplex , Regulación de la Expresión Génica , Humanos
12.
Biochem Soc Trans ; 49(1): 281-295, 2021 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-33439253

RESUMEN

Although transport into the nucleus mediated by the importin (IMP) α/ß1-heterodimer is central to viral infection, small molecule inhibitors of IMPα/ß1-dependent nuclear import have only been described and shown to have antiviral activity in the last decade. Their robust antiviral activity is due to the strong reliance of many different viruses, including RNA viruses such as human immunodeficiency virus-1 (HIV-1), dengue (DENV), and Zika (ZIKV), on the IMPα/ß1-virus interface. High-throughput compound screens have identified many agents that specifically target this interface. Of these, agents targeting IMPα/ß1 directly include the FDA-approved macrocyclic lactone ivermectin, which has documented broad-spectrum activity against a whole range of viruses, including HIV-1, DENV1-4, ZIKV, West Nile virus (WNV), Venezuelan equine encephalitis virus, chikungunya, and most recently, SARS-CoV-2 (COVID-19). Ivermectin has thus far been tested in Phase III human clinical trials for DENV, while there are currently close to 80 trials in progress worldwide for SARS-CoV-2; preliminary results for randomised clinical trials (RCTs) as well as observational/retrospective studies are consistent with ivermectin affording clinical benefit. Agents that target the viral component of the IMPα/ß1-virus interface include N-(4-hydroxyphenyl) retinamide (4-HPR), which specifically targets DENV/ZIKV/WNV non-structural protein 5 (NS5). 4-HPR has been shown to be a potent inhibitor of infection by DENV1-4, including in an antibody-dependent enhanced animal challenge model, as well as ZIKV, with Phase II clinical challenge trials planned. The results from rigorous RCTs will help determine the therapeutic potential of the IMPα/ß1-virus interface as a target for antiviral development.


Asunto(s)
Ivermectina/farmacología , Proteínas no Estructurales Virales/metabolismo , Virosis/prevención & control , Virus/metabolismo , alfa Carioferinas/metabolismo , beta Carioferinas/metabolismo , Animales , Antivirales/farmacología , Humanos , Unión Proteica/efectos de los fármacos , Virosis/metabolismo , Virosis/virología , Virus/patogenicidad
13.
Opt Express ; 29(15): 23611-23621, 2021 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-34614624

RESUMEN

Artificial neural networks are capable of fitting highly non-linear and complex systems. Such complicated systems can be found everywhere in nature, including the non-linear interaction between optical modes in laser resonators. In this work, we demonstrate artificial neural networks trained to model these complex interactions in the cavity of a Quantum Cascade Random Laser. The neural networks are able to predict modulation schemes for desired laser spectra in real-time. This radically novel approach makes it possible to adapt spectra to individual requirements without the need for lengthy and costly simulation and fabrication iterations.

14.
Mol Cell ; 52(5): 655-66, 2013 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-24332176

RESUMEN

Most secretory preproteins exit bacterial cells through the protein translocase, comprising the SecYEG channel and the dimeric peripheral ATPase motor SecA. Energetic coupling to work remains elusive. We now demonstrate that translocation is driven by unusually dynamic quaternary changes in SecA. The dimer occupies several successive states with distinct protomer arrangements. SecA docks on SecYEG as a dimer and becomes functionally asymmetric. Docking occurs via only one protomer. The second protomer allosterically regulates downstream steps. Binding of one preprotein signal peptide to the SecYEG-docked SecA protomer elongates the SecA dimer and triggers the translocase holoenzyme to obtain a lower activation energy conformation. ATP hydrolysis monomerizes the triggered SecA dimer, causing mature chain trapping and processive translocation. This is a unique example of one protein exploiting quaternary dynamics to become a substrate receptor, a "loading clamp," and a "processive motor." This mechanism has widespread implications on protein translocases, chaperones, and motors.


Asunto(s)
Adenosina Trifosfatasas/genética , Adenosina Trifosfatasas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Adenosina Trifosfato/metabolismo , Catálisis , Dimerización , Escherichia coli/genética , Escherichia coli/metabolismo , Hidrólisis , Mutación , Unión Proteica , Conformación Proteica , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Transporte de Proteínas , Canales de Translocación SEC , Proteína SecA
15.
Graefes Arch Clin Exp Ophthalmol ; 259(2): 335-341, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32926193

RESUMEN

PURPOSE: Complicated retinal re-detachment with inferior proliferative vitreoretinopathy (PVR) remains a challenge. This study's aim was to compare vitrectomy with conventional silicon oil (CSO) combined with an encircling band (EB) and vitrectomy with heavy silicon oil (HSO) alone to treat retinal re-detachment through inferior PVR, where standard procedures have already failed. METHODS: A retrospective analysis was done on patients with inferior complex re-detachment with secondary PVR after primary surgery, who received pars plana vitrectomy (PPV) with CSO combined with EB (group 1) or PPV alone with HSO (group 2) between December 2006 and August 2017. The primary endpoint was retinal reattachment, and the secondary endpoint was visual acuity (VA) change and complications in both groups. RESULTS: This study included 119 eyes. Total single surgery anatomical success (SSAS) was 64%, with 80% (52/65) achieved in group 1 and 44.5% (24/54) in group 2 (p < 0.0001). The total final anatomical success (FAS) rate was 79% (94/119). In group 1, FAS was 91% (59/65) compared with 65% (35/54) in group 2 (p = 0.003). The pretreatment VA of group 1 had a median of 1.4 logMAR (95% CI 0.3-1.8), and group 2 showed a median of 1.4 logMAR (95% CI 0.2-1.8). The post-treatment decrease in group 1 was a median equal to - 0.6 versus - 0.1 for group 2 (p = 0.0001). Serious complications were similar in both groups. CONCLUSION: For complicated retinal re-detachment through inferior PVR, the combination of PPV with EB may lead to better anatomical (SSAS, FAS) and functional success compared with PPV alone with HSO.


Asunto(s)
Desprendimiento de Retina , Vitreorretinopatía Proliferativa , Humanos , Desprendimiento de Retina/cirugía , Estudios Retrospectivos , Aceites de Silicona , Resultado del Tratamiento , Agudeza Visual , Vitrectomía , Vitreorretinopatía Proliferativa/cirugía
16.
Biochem J ; 477(9): 1579-1599, 2020 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-32297642

RESUMEN

Osteosarcoma and chondrosarcoma are sarcomas of the bone and the cartilage that are primarily treated by surgical intervention combined with high toxicity chemotherapy. In search of alternative metabolic approaches to address the challenges in treating bone sarcomas, we assessed the growth dependence of these cancers on leucine, one of the branched-chain amino acids (BCAAs), and BCAA metabolism. Tumor biopsies from bone sarcoma patients revealed differential expression of BCAA metabolic enzymes. The cytosolic branched-chain aminotransferase (BCATc) that is commonly overexpressed in cancer cells, was down-regulated in chondrosarcoma (SW1353) in contrast with osteosarcoma (143B) cells that expressed both BCATc and its mitochondrial isoform BCATm. Treating SW1353 cells with gabapentin, a selective inhibitor of BCATc, further revealed that these cells failed to respond to gabapentin. Application of the structural analog of leucine, N-acetyl-leucine amide (NALA) to disrupt leucine uptake, indicated that all bone sarcoma cells used leucine to support their energy metabolism and biosynthetic demands. This was evident from the increased activity of the energy sensor AMP-activated protein kinase (AMPK), down-regulation of complex 1 of the mammalian target of rapamycin (mTORC1), and reduced cell viability in response to NALA. The observed changes were most profound in the 143B cells, which appeared highly dependent on cytosolic and mitochondrial BCAA metabolism. This study thus demonstrates that bone sarcomas rely on leucine and BCAA metabolism for energy and growth; however, the differential expression of BCAA enzymes and the presence of other carbon sources may dictate how efficiently these cancer cells take advantage of BCAA metabolism.


Asunto(s)
Aminoácidos de Cadena Ramificada/metabolismo , Condrosarcoma/metabolismo , Leucina/metabolismo , Osteosarcoma/metabolismo , Transducción de Señal , Proteínas Quinasas Activadas por AMP/metabolismo , Neoplasias Óseas/metabolismo , Línea Celular Tumoral , Citosol/metabolismo , Metabolismo Energético , Humanos , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Mitocondrias/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Transaminasas/metabolismo
17.
J Wound Care ; 30(Sup2): S12-S17, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33573492

RESUMEN

COVID-19 is highly contagious and its rapid spread burdens the healthcare system. As the number of confirmed cases goes up, the shortage of medical resources has become a challenge. To avoid the collapse of the healthcare system during the fight with COVID-19, all healthcare workers, including wound care practitioners, should adapt to new roles and use any appropriate methods available to slow the spread of the virus. Integrating telemedicine into wound care during the outbreak helps maintain social distancing, preserve personal protective equipment and medical resources, and eliminate unnecessary exposure for both vulnerable patients and high-risk healthcare workers.


Asunto(s)
Atención Ambulatoria , COVID-19/prevención & control , Pie Diabético/terapia , Telemedicina , Triaje , Heridas y Lesiones/terapia , Infección Hospitalaria/prevención & control , Procedimientos Quirúrgicos Electivos , Hospitalización , Humanos , Transmisión de Enfermedad Infecciosa de Paciente a Profesional/prevención & control , SARS-CoV-2
18.
Artículo en Alemán | MEDLINE | ID: mdl-33890260

RESUMEN

Gitelman syndrome is a rare inherited renal tubulopathy characterized by hypokalemia, hypomagnesemia and metabolic alcalosis. It is caused by a mutation in the SLC12A3 gene leading to a dysfunction of the thiazide-sensitive sodium chloride cotransporter and the magnesium transporters in the distal convoluted tubules. Only few reports of pregnant woman with Gitelman syndrome exist. Due to many unsolved questions about the impact on pregnancy and the maternal and fetal outcome, the obstetric and anesthesiological management remains a challenge. We discuss the case of a primary cesarean delivery in a 22-year-old woman with a new diagnosed Gitelman syndrome focusing on the anesthesiological approach.


Asunto(s)
Síndrome de Gitelman , Hipopotasemia , Adulto , Femenino , Síndrome de Gitelman/diagnóstico , Síndrome de Gitelman/genética , Humanos , Hipopotasemia/diagnóstico , Magnesio , Mutación , Embarazo , Miembro 3 de la Familia de Transportadores de Soluto 12/genética , Adulto Joven
19.
Angew Chem Int Ed Engl ; 60(33): 17952-17956, 2021 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-34129261

RESUMEN

Given the inherent performance limitations of intercalation-based lithium-ion batteries, solid-state conversion batteries are promising systems for future energy storage. A high specific capacity and natural abundancy make iron disulfide (FeS2 ) a promising cathode-active material. In this work, FeS2 nanoparticles were prepared solvothermally. By adjusting the synthesis conditions, samples with average particle diameters between 10 nm and 35 nm were synthesized. The electrochemical performance was evaluated in solid-state cells with a Li-argyrodite solid electrolyte. While the reduction of FeS2 was found to be irreversible in the initial discharge, a stable cycling of the reduced species was observed subsequently. A positive effect of smaller particle dimensions on FeS2 utilization was identified, which can be attributed to a higher interfacial contact area and shortened diffusion pathways inside the FeS2 particles. These results highlight the general importance of morphological design to exploit the promising theoretical capacity of conversion electrodes in solid-state batteries.

20.
Psychol Sci ; 31(9): 1107-1116, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32790528

RESUMEN

Similarities among the world's languages may be driven by universal features of human cognition or perception. For example, in many languages, complex words are formed by adding suffixes to the ends of simpler words, but adding prefixes is much less common: Why might this be? Previous research suggests this is due to a domain-general perceptual bias: Sequences differing at their ends are perceived as more similar to each other than sequences differing at their beginnings. However, as is typical in psycholinguistic research, the evidence comes exclusively from one population-English speakers-who have extensive experience with suffixing. Here, we provided a much stronger test of this claim by investigating perceptual-similarity judgments in speakers of Kîîtharaka, a heavily prefixing Bantu language spoken in rural Kenya. We found that Kîîtharaka speakers (N = 72) showed the opposite judgments to English speakers (N = 51), which calls into question whether a universal bias in human perception can explain the suffixing preference in the world's languages.


Asunto(s)
Lenguaje , Percepción del Habla , Percepción del Tiempo , Juicio , Kenia , Psicolingüística
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA