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1.
Immunity ; 57(6): 1413-1427.e9, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38823390

RESUMO

Influenza B viruses (IBVs) comprise a substantial portion of the circulating seasonal human influenza viruses. Here, we describe the isolation of human monoclonal antibodies (mAbs) that recognized the IBV neuraminidase (NA) glycoprotein from an individual following seasonal vaccination. Competition-binding experiments suggested the antibodies recognized two major antigenic sites. One group, which included mAb FluB-393, broadly inhibited IBV NA sialidase activity, protected prophylactically in vivo, and bound to the lateral corner of NA. The second group contained an active site mAb, FluB-400, that broadly inhibited IBV NA sialidase activity and virus replication in vitro in primary human respiratory epithelial cell cultures and protected against IBV in vivo when administered systemically or intranasally. Overall, the findings described here shape our mechanistic understanding of the human immune response to the IBV NA glycoprotein through the demonstration of two mAb delivery routes for protection against IBV and the identification of potential IBV therapeutic candidates.


Assuntos
Anticorpos Monoclonais , Anticorpos Antivirais , Vírus da Influenza B , Influenza Humana , Neuraminidase , Neuraminidase/imunologia , Humanos , Vírus da Influenza B/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Vacinas contra Influenza/imunologia , Camundongos , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Proteínas Virais/imunologia , Replicação Viral/efeitos dos fármacos
2.
Genome Res ; 34(5): 778-783, 2024 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-38692839

RESUMO

In silico simulation of high-throughput sequencing data is a technique used widely in the genomics field. However, there is currently a lack of effective tools for creating simulated data from nanopore sequencing devices, which measure DNA or RNA molecules in the form of time-series current signal data. Here, we introduce Squigulator, a fast and simple tool for simulation of realistic nanopore signal data. Squigulator takes a reference genome, a transcriptome, or read sequences, and generates corresponding raw nanopore signal data. This is compatible with basecalling software from Oxford Nanopore Technologies (ONT) and other third-party tools, thereby providing a useful substrate for development, testing, debugging, validation, and optimization at every stage of a nanopore analysis workflow. The user may generate data with preset parameters emulating specific ONT protocols or noise-free "ideal" data, or they may deterministically modify a range of experimental variables and/or noise parameters to shape the data to their needs. We present a brief example of Squigulator's use, creating simulated data to model the degree to which different parameters impact the accuracy of ONT basecalling and downstream variant detection. This analysis reveals new insights into the nature of ONT data and basecalling algorithms. We provide Squigulator as an open-source tool for the nanopore community.


Assuntos
Sequenciamento por Nanoporos , Software , Sequenciamento por Nanoporos/métodos , Simulação por Computador , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Nanoporos , Humanos , Genômica/métodos , Análise de Sequência de DNA/métodos , Algoritmos
3.
J Am Chem Soc ; 146(1): 532-542, 2024 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-38134439

RESUMO

Aggregation of transthyretin (TTR) is associated with devastating amyloid diseases. Amyloidosis begins with the dissociation of the native homotetramer (a dimer of dimers) to form a monomeric intermediate that assembles into pathogenic aggregates. This process is accelerated in vitro at low pH, but the process by which TTR dissociates and reassembles at neutral pH remains poorly characterized due to the low population of intermediates. Here, we use 19F-nuclear magnetic resonance (NMR) and a highly sensitive trifluoromethyl probe to determine the relative populations of the species formed by the dissociation of a destabilized variant, A25T. The A25T mutation perturbs both the strong dimer and weak dimer-dimer interfaces. A tetramer ⇌ dimer ⇌ monomer (TDM) equilibrium model is proposed to account for concentration- and temperature-dependent population changes. Thermodynamic and kinetic parameters and activation energetics for dissociation of the native A25T tetramer, as well as a destabilized alternative tetramer (T*) with a mispacked F87 side chain, were extracted by van't Hoff and 19F-NMR line shape analysis, saturation transfer, and transition state theory. Chemical shifts for the dimer and T* species are degenerate for 19F and methyl probes close to the strong dimer interface, implicating interfacial perturbation as a common structural feature of these destabilized species. All-atom molecular dynamics simulations further suggest more frequent F87 ring flipping on the nanosecond time scale in the A25T dimer than in the native A25T tetramer. Our integrated approach offers quantitative insights into the energy landscape of the dissociation pathway of TTR at neutral pH.


Assuntos
Pré-Albumina , Pré-Albumina/genética , Pré-Albumina/química , Pré-Albumina/metabolismo , Mutação , Espectroscopia de Ressonância Magnética
4.
Am Heart J ; 271: 182-187, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38658076

RESUMO

In the Emergency Department, patients with suspected myocardial infarction can be risk stratified using the HEART pathway, which has recently been amended for prehospital use and modified for the incorporation of a high-sensitivity cardiac troponin test. In a prospective analysis, the performance of both HEART pathways in the prehospital setting, with a high-sensitivity cardiac troponin test using 3 different thresholds, was evaluated for major adverse cardiac events at 30 days. We found that both low-risk HEART pathways, when using the most conservative cardiac troponin thresholds, approached but did not reach accepted rule-out performance in the Emergency Department.


Assuntos
Serviços Médicos de Emergência , Infarto do Miocárdio , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/sangue , Serviços Médicos de Emergência/métodos , Estudos Prospectivos , Medição de Risco/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Biomarcadores/sangue , Serviço Hospitalar de Emergência , Pessoal Técnico de Saúde , Troponina/sangue , Auxiliares de Emergência , Paramédico
5.
J Virol ; 97(11): e0070523, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37843370

RESUMO

IMPORTANCE: The lack of a reliable method to accurately detect when replication-competent HIV has been cleared is a major challenge in developing a cure. This study introduces a new approach called the HIVepsilon-seq (HIVε-seq) assay, which uses long-read sequencing technology and bioinformatics to scrutinize the HIV genome at the nucleotide level, distinguishing between defective and intact HIV. This study included 30 participants on antiretroviral therapy, including 17 women, and was able to discriminate between defective and genetically intact viruses at the single DNA strand level. The HIVε-seq assay is an improvement over previous methods, as it requires minimal sample, less specialized lab equipment, and offers a shorter turnaround time. The HIVε-seq assay offers a promising new tool for researchers to measure the intact HIV reservoir, advancing efforts towards finding a cure for this devastating disease.


Assuntos
Infecções por HIV , HIV , Provírus , Feminino , Humanos , Linfócitos T CD4-Positivos , DNA Viral/genética , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Nucleotídeos , Provírus/genética , Carga Viral , Análise de Sequência de DNA , Masculino , Fatores Sexuais , HIV/genética
6.
Bioinformatics ; 39(6)2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37252813

RESUMO

MOTIVATION: Nanopore sequencing is emerging as a key pillar in the genomic technology landscape but computational constraints limiting its scalability remain to be overcome. The translation of raw current signal data into DNA or RNA sequence reads, known as 'basecalling', is a major friction in any nanopore sequencing workflow. Here, we exploit the advantages of the recently developed signal data format 'SLOW5' to streamline and accelerate nanopore basecalling on high-performance computing (HPC) and cloud environments. RESULTS: SLOW5 permits highly efficient sequential data access, eliminating a potential analysis bottleneck. To take advantage of this, we introduce Buttery-eel, an open-source wrapper for Oxford Nanopore's Guppy basecaller that enables SLOW5 data access, resulting in performance improvements that are essential for scalable, affordable basecalling. AVAILABILITY AND IMPLEMENTATION: Buttery-eel is available at https://github.com/Psy-Fer/buttery-eel.


Assuntos
Nanoporos , Software , Análise de Sequência de DNA/métodos , Genoma , Genômica , Sequenciamento de Nucleotídeos em Larga Escala
7.
Liver Transpl ; 30(1): 30-45, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-38109282

RESUMO

Normothermic machine perfusion (NMP) enables pretransplant assessment of high-risk donor livers. The VITTAL trial demonstrated that 71% of the currently discarded organs could be transplanted with 100% 90-day patient and graft survivals. Here, we report secondary end points and 5-year outcomes of this prospective, open-label, phase 2 adaptive single-arm study. The patient and graft survivals at 60 months were 82% and 72%, respectively. Four patients lost their graft due to nonanastomotic biliary strictures, one caused by hepatic artery thrombosis in a liver donated following brain death, and 3 in elderly livers donated after circulatory death (DCD), which all clinically manifested within 6 months after transplantation. There were no late graft losses for other reasons. All the 4 patients who died during the study follow-up had functioning grafts. Nonanastomotic biliary strictures developed in donated after circulatory death livers that failed to produce bile with pH >7.65 and bicarbonate levels >25 mmol/L. Histological assessment in these livers revealed high bile duct injury scores characterized by arterial medial necrosis. The quality of life at 6 months significantly improved in all but 4 patients suffering from nonanastomotic biliary strictures. This first report of long-term outcomes of high-risk livers assessed by normothermic machine perfusion demonstrated excellent 5-year survival without adverse effects in all organs functioning beyond 1 year (ClinicalTrials.gov number NCT02740608).


Assuntos
Transplante de Fígado , Idoso , Humanos , Constrição Patológica/etiologia , Fígado/cirurgia , Transplante de Fígado/efeitos adversos , Preservação de Órgãos , Perfusão , Estudos Prospectivos , Qualidade de Vida
8.
J Biol Chem ; 298(8): 102162, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35724960

RESUMO

Transthyretin (TTR) amyloidosis is associated with tissue deposition of TTR aggregates. TTR aggregation is initiated by dissociation of the native tetramer to form a monomeric intermediate, which locally unfolds and assembles into soluble oligomers and higher-order aggregates. However, a detailed mechanistic understanding requires kinetic and structural characterization of the low population intermediates formed. Here, we show that the monomeric intermediate exchanges with an ensemble of oligomers on the millisecond timescale. This transient and reversible exchange causes broadening of the 19F resonance of a trifluoromethyl probe coupled to the monomeric intermediate at S85C. We show the 19F linewidth and R2 relaxation rate increase with increasing concentration of the oligomer. Furthermore, introduction of 19F probes at additional TTR sites yielded distinct 19F chemical shifts for the TTR tetramer and monomer when the trifluoromethyl probe was attached at S100C, located near the same subunit interface as S85C, but not with probes attached at S46C or E63C, which are distant from any interfaces. The 19F probe at E63C shows that part of the DE loop, which is solvent accessible in the tetramer, becomes more buried in the NMR-visible oligomers. Finally, using backbone amides as probes, we show that parts of the EF helix and H-strand become highly flexible in the otherwise structured monomeric intermediate at acidic pH. We further find that TTR aggregation can be reversed by increasing pH. Taken together, this work provides insights into location-dependent conformational changes in the reversible early steps of a kinetically concerted TTR aggregation pathway.


Assuntos
Amiloidose , Pré-Albumina , Agregados Proteicos , Amiloide/química , Cinética , Pré-Albumina/química , Agregação Patológica de Proteínas , Conformação Proteica
9.
Clin Gastroenterol Hepatol ; 21(3): 694-703.e8, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35337981

RESUMO

BACKGROUND & AIMS: The clinical course of cirrhosis does not follow a predictable trajectory. Transient elastography (TE) is commonly used in clinical practice to diagnose liver fibrosis and increasingly to risk stratify patients. The aim of this study was to assess the natural history of advanced chronic liver disease (ACLD) defined by TE using electronic health record (EHR) data in a multistate framework. METHODS: TE data were collected between 2008 and 2019. Patients with a liver stiffness measurement (LSM) >10 kPa were included. Disease and procedure code information held in EHR was analyzed. Clinical events including decompensation, hepatocellular carcinoma (HCC), and death were identified. Outcomes were described in a multistate model using flexible parametric survival methods including LSM and the albumin bilirubin (ALBI) score. RESULTS: Three thousand and twenty eight patients were included. Median follow up was 3.1 years. LSM and ALBI were associated with the development of varices and decompensation, and ALBI, age, sex, and viral liver disease were associated with the development of HCC from the compensated state. The cumulative incidence of HCC before decompensation was low for patients with alcohol-related liver disease (3.8%) and nonalcoholic fatty liver disease (1.3%) at 5 years after TE. Importantly, death was predicted to occur before decompensation or HCC in most cases. CONCLUSIONS: Liver stiffness, ALBI score, and disease etiology are each associated with outcomes in a large contemporary cohort with ACLD. EHR data can be used to define clinical progression in these patients, facilitating large clinical effectiveness trials and cost-effectiveness analyses.


Assuntos
Carcinoma Hepatocelular , Técnicas de Imagem por Elasticidade , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Técnicas de Imagem por Elasticidade/métodos , Fígado/patologia , Cirrose Hepática/complicações
10.
Genome Res ; 30(9): 1345-1353, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32907883

RESUMO

Nanopore sequencing enables direct measurement of RNA molecules without conversion to cDNA, thus opening the gates to a new era for RNA biology. However, the lack of molecular barcoding of direct RNA nanopore sequencing data sets severely affects the applicability of this technology to biological samples, where RNA availability is often limited. Here, we provide the first experimental protocol and associated algorithm to barcode and demultiplex direct RNA nanopore sequencing data sets. Specifically, we present a novel and robust approach to accurately classify raw nanopore signal data by transforming current intensities into images or arrays of pixels, followed by classification using a deep learning algorithm. We demonstrate the power of this strategy by developing the first experimental protocol for barcoding and demultiplexing direct RNA sequencing libraries. Our method, DeePlexiCon, can classify 93% of reads with 95.1% accuracy or 60% of reads with 99.9% accuracy. The availability of an efficient and simple multiplexing strategy for native RNA sequencing will improve the cost-effectiveness of this technology, as well as facilitate the analysis of lower-input biological samples. Overall, our work exemplifies the power, simplicity, and robustness of signal-to-image conversion for nanopore data analysis using deep learning.


Assuntos
Aprendizado Profundo , Sequenciamento por Nanoporos/métodos , Análise de Sequência de RNA/métodos , Algoritmos
11.
Bioinformatics ; 38(5): 1443-1446, 2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-34908106

RESUMO

MOTIVATION: InterARTIC is an interactive web application for the analysis of viral whole-genome sequencing (WGS) data generated on Oxford Nanopore Technologies (ONT) devices. A graphical interface enables users with no bioinformatics expertise to analyze WGS experiments and reconstruct consensus genome sequences from individual isolates of viruses, such as SARS-CoV-2. InterARTIC is intended to facilitate widespread adoption and standardization of ONT sequencing for viral surveillance and molecular epidemiology. RESULTS: We demonstrate the use of InterARTIC for the analysis of ONT viral WGS data from SARS-CoV-2 and Ebola virus, using a laptop computer or the internal computer on an ONT GridION sequencing device. We showcase the intuitive graphical interface, workflow customization capabilities and job-scheduling system that facilitate execution of small- and large-scale WGS projects on any common virus. AVAILABILITY AND IMPLEMENTATION: InterARTIC is a free, open-source web application implemented in Python that executes best-practice command line workflows from the ARTIC network. The application can be downloaded as a set of pre-compiled binaries that are compatible with all common Linux distributions, Windows with Linux subsystems, MacOSX and ARM systems. All code can be found on GitHub at https://github.com/Psy-Fer/interARTIC/ and documentation can be found at https://github.com/Psy-Fer/interARTIC/. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
COVID-19 , Sequenciamento por Nanoporos , Nanoporos , Humanos , SARS-CoV-2/genética , Software , Genoma Viral
12.
Emerg Med J ; 40(7): 474-481, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37268413

RESUMO

INTRODUCTION: The History, Electrocardiogram (ECG), Age, Risk Factors and Troponin (HEART) score is commonly used to risk stratify patients with possible myocardial infarction as low risk or high risk in the Emergency Department (ED). Whether the HEART score can be used by paramedics to guide care were high-sensitivity cardiac troponin testing available in a prehospital setting is uncertain. METHODS: In a prespecified secondary analysis of a prospective cohort study where paramedics enrolled patients with suspected myocardial infarction, a paramedic Heart, ECG, Age, Risk Factors (HEAR) score was recorded contemporaneously, and a prehospital blood sample was obtained for subsequent cardiac troponin testing. HEART and modified HEART scores were derived using laboratory contemporary and high-sensitivity cardiac troponin I assays. HEART and modified HEART scores of ≤3 and ≥7 were applied to define low-risk and high-risk patients, and performance was evaluated for an outcome of major adverse cardiac events (MACEs) at 30 days. RESULTS: Between November 2014 and April 2018, 1054 patients were recruited, of whom 960 (mean 64 (SD 15) years, 42% women) were eligible for analysis and 255 (26%) experienced a MACE at 30 days. A HEART score of ≤3 identified 279 (29%) as low risk with a negative predictive value of 93.5% (95% CI 90.0% to 95.9%) for the contemporary assay and 91.4% (95% CI 87.5% to 94.2%) for the high-sensitivity assay. A modified HEART score of ≤3 using the limit of detection of the high-sensitivity assay identified 194 (20%) patients as low risk with a negative predictive value of 95.9% (95% CI 92.1% to 97.9%). A HEART score of ≥7 using either assay gave a lower positive predictive value than using the upper reference limit of either cardiac troponin assay alone. CONCLUSIONS: A HEART score derived by paramedics in the prehospital setting, even when modified to harness the precision of a high-sensitivity assay, does not allow safe rule-out of myocardial infarction or enhanced rule-in compared with cardiac troponin testing alone.


Assuntos
Síndrome Coronariana Aguda , Infarto do Miocárdio , Humanos , Feminino , Masculino , Estudos Prospectivos , Síndrome Coronariana Aguda/diagnóstico , Dor no Peito/etiologia , Medição de Risco , Troponina I , Serviço Hospitalar de Emergência , Eletrocardiografia , Biomarcadores
13.
Dev Biol ; 478: 25-40, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34166654

RESUMO

Skin development and patterning is dependent on factors that regulate the stepwise differentiation of dermal fibroblasts concomitant with dermal-epidermal reciprocal signaling, two processes that are poorly understood. Here we show that dermal EZH2, the methyltransferase enzyme of the epigenetic Polycomb Repressive Complex 2 (PRC2), is a new coordinator of both these processes. Dermal EZH2 activity is present during dermal fibroblast differentiation and is required for spatially restricting Wnt/ß-catenin signaling to reinforce dermal fibroblast cell fate. Later in development, dermal EZH2 regulates the expression of reticular dermal markers and initiation of secondary hair follicles. Embryos lacking dermal Ezh2 have elevated epidermal proliferation and differentiation that can be rescued by small molecule inhibition of retinoic acid (RA) signaling. Together, our study reveals that dermal EZH2 is acting like a rheostat to control the levels of Wnt/ß-catenin and RA signaling to impact fibroblast differentiation cell autonomously and epidermal keratinocyte development non-cell autonomously, respectively.


Assuntos
Derme/citologia , Derme/embriologia , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Epiderme/embriologia , Fibroblastos/citologia , Queratinócitos/citologia , Complexo Repressor Polycomb 2/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Derme/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Epiderme/metabolismo , Fibroblastos/metabolismo , Hiperplasia , Queratinócitos/metabolismo , Camundongos , Organogênese , Retinoides/farmacologia , Transdução de Sinais , Células-Tronco/citologia , Células-Tronco/metabolismo , Tretinoína/metabolismo , Via de Sinalização Wnt , beta Catenina/metabolismo
14.
PLoS Med ; 19(4): e1003954, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35385471

RESUMO

BACKGROUND: The importance of patient-reported outcome measurement in chronic kidney disease (CKD) populations has been established. However, there remains a lack of research that has synthesised data around CKD-specific symptom and health-related quality of life (HRQOL) burden globally, to inform focused measurement of the most relevant patient-important information in a way that minimises patient burden. The aim of this review was to synthesise symptom prevalence/severity and HRQOL data across the following CKD clinical groups globally: (1) stage 1-5 and not on renal replacement therapy (RRT), (2) receiving dialysis, or (3) in receipt of a kidney transplant. METHODS AND FINDINGS: MEDLINE, PsycINFO, and CINAHL were searched for English-language cross-sectional/longitudinal studies reporting prevalence and/or severity of symptoms and/or HRQOL in CKD, published between January 2000 and September 2021, including adult patients with CKD, and measuring symptom prevalence/severity and/or HRQOL using a patient-reported outcome measure (PROM). Random effects meta-analyses were used to pool data, stratified by CKD group: not on RRT, receiving dialysis, or in receipt of a kidney transplant. Methodological quality of included studies was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data, and an exploration of publication bias performed. The search identified 1,529 studies, of which 449, with 199,147 participants from 62 countries, were included in the analysis. Studies used 67 different symptom and HRQOL outcome measures, which provided data on 68 reported symptoms. Random effects meta-analyses highlighted the considerable symptom and HRQOL burden associated with CKD, with fatigue particularly prevalent, both in patients not on RRT (14 studies, 4,139 participants: 70%, 95% CI 60%-79%) and those receiving dialysis (21 studies, 2,943 participants: 70%, 95% CI 64%-76%). A number of symptoms were significantly (p < 0.05 after adjustment for multiple testing) less prevalent and/or less severe within the post-transplantation population, which may suggest attribution to CKD (fatigue, depression, itching, poor mobility, poor sleep, and dry mouth). Quality of life was commonly lower in patients on dialysis (36-Item Short Form Health Survey [SF-36] Mental Component Summary [MCS] 45.7 [95% CI 45.5-45.8]; SF-36 Physical Component Summary [PCS] 35.5 [95% CI 35.3-35.6]; 91 studies, 32,105 participants for MCS and PCS) than in other CKD populations (patients not on RRT: SF-36 MCS 66.6 [95% CI 66.5-66.6], p = 0.002; PCS 66.3 [95% CI 66.2-66.4], p = 0.002; 39 studies, 24,600 participants; transplant: MCS 50.0 [95% CI 49.9-50.1], p = 0.002; PCS 48.0 [95% CI 47.9-48.1], p = 0.002; 39 studies, 9,664 participants). Limitations of the analysis are the relatively few studies contributing to symptom severity estimates and inconsistent use of PROMs (different measures and time points) across the included literature, which hindered interpretation. CONCLUSIONS: The main findings highlight the considerable symptom and HRQOL burden associated with CKD. The synthesis provides a detailed overview of the symptom/HRQOL profile across clinical groups, which may support healthcare professionals when discussing, measuring, and managing the potential treatment burden associated with CKD. PROTOCOL REGISTRATION: PROSPERO CRD42020164737.


Assuntos
Qualidade de Vida , Insuficiência Renal Crônica , Adulto , Estudos Transversais , Fadiga , Humanos , Diálise Renal , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/terapia
15.
Lancet ; 397(10286): 1770-1780, 2021 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-33714360

RESUMO

This Review, in addressing the unacceptably high mortality of patients with liver disease admitted to acute hospitals, reinforces the need for integrated clinical services. The masterplan described is based on regional, geographically sited liver centres, each linked to four to six surrounding district general hospitals-a pattern of care similar to that successfully introduced for stroke services. The plan includes the establishment of a lead and deputy lead clinician in each acute hospital, preferably a hepatologist or gastroenterologist with a special interest in liver disease, who will have prime responsibility for organising the care of admitted patients with liver disease on a 24/7 basis. Essential for the plan is greater access to intensive care units and high-dependency units, in line with the reconfiguration of emergency care due to the COVID-19 pandemic. This Review strongly recommends full implementation of alcohol care teams in hospitals and improved working links with acute medical services. We also endorse recommendations from paediatric liver services to improve overall survival figures by diagnosing biliary atresia earlier based on stool colour charts and better caring for patients with impaired cognitive ability and developmental mental health problems. Pilot studies of earlier diagnosis have shown encouraging progress, with 5-6% of previously undiagnosed cases of severe fibrosis or cirrhosis identified through use of a portable FibroScan in primary care. Similar approaches to the detection of early asymptomatic disease are described in accounts from the devolved nations, and the potential of digital technology in improving the value of clinical consultation and screening programmes in primary care is highlighted. The striking contribution of comorbidities, particularly obesity and diabetes (with excess alcohol consumption known to be a major factor in obesity), to mortality in COVID-19 reinforces the need for fiscal and other long delayed regulatory measures to reduce the prevalence of obesity. These measures include the food sugar levy and the introduction of the minimum unit price policy to reduce alcohol consumption. Improving public health, this Review emphasises, will not only mitigate the severity of further waves of COVID-19, but is crucial to reducing the unacceptable burden from liver disease in the UK.


Assuntos
Hospitalização , Hepatopatias/prevenção & controle , Diagnóstico Precoce , Humanos , Hepatopatias/diagnóstico , Reino Unido
16.
World J Urol ; 40(3): 671-677, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34132897

RESUMO

Image-guidance during partial nephrectomy enables navigation within the operative field alongside a 3-dimensional roadmap of renal anatomy generated from patient-specific imaging. Once a process is performed by the human mind, the technology will allow standardization of the task for the benefit of all patients undergoing robot-assisted partial nephrectomy. Any surgeon will be able to visualize the kidney and key subsurface landmarks in real-time within a 3-dimensional simulation, with the goals of improving operative efficiency, decreasing surgical complications, and improving oncologic outcomes. For similar purposes, image-guidance has already been adopted as a standard of care in other surgical fields; we are now at the brink of this in urology. This review summarizes touch-based approaches to image-guidance during partial nephrectomy, as the technology begins to enter in vivo human evaluation. The processes of segmentation, localization, registration, and re-registration are all described with seamless integration into the da Vinci surgical system; this will facilitate clinical adoption sooner.


Assuntos
Neoplasias Renais , Procedimentos Cirúrgicos Robóticos , Robótica , Humanos , Rim/cirurgia , Neoplasias Renais/cirurgia , Nefrectomia/métodos , Tato
17.
Biochemistry ; 60(10): 756-764, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33645214

RESUMO

Misfolding and aggregation of transthyretin (TTR) are linked to amyloid disease. Amyloidosis occurs when the TTR homotetramer dissociates into aggregation-prone monomers that self-assemble into amyloid. In familial transthyretin amyloidosis, hereditary amino acid substitutions destabilize TTR and promote aggregation. In this work, we used 19F nuclear magnetic resonance (NMR) to determine the effect of mutations in the EF helix (Y78F, K80D, K80E, and A81T) and EF loop (G83R and I84S) on the aggregation kinetics and stability of the TTR tetramer and monomer. The EF region acts as a scaffold that stabilizes interactions in both the strong and weak dimer interfaces of the tetramer and is the site of a cluster of pathogenic mutations. K80D and K80E are non-natural mutants that destabilize the EF helix and yield an equilibrium mixture of tetramer and monomer at neutral pH, providing a unique opportunity to determine the thermodynamic parameters for tetramer assembly under nondenaturing conditions. Of the pathogenic mutants studied, only A81T formed appreciable monomer at neutral pH. Real-time 19F NMR measurements showed that the pathogenic Y78F mutation accelerates aggregation by destabilizing both the tetrameric and monomeric species. The pathogenic mutations A81T, G83R, and I84S destabilize the monomer and increase its aggregation rate by disrupting a Schellman helix C-capping motif. These studies provide new insights into the mechanism by which relatively subtle mutations that affect tetramer or monomer stability promote entry of TTR into the dissociation-aggregation pathway.


Assuntos
Amiloide/química , Pré-Albumina/química , Pré-Albumina/metabolismo , Termodinâmica , Sítios de Ligação , Humanos , Cinética , Modelos Moleculares , Mutação , Pré-Albumina/genética , Conformação Proteica
18.
BMC Genomics ; 22(1): 188, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33726677

RESUMO

BACKGROUND: Basenjis are considered an ancient dog breed of central African origins that still live and hunt with tribesmen in the African Congo. Nicknamed the barkless dog, Basenjis possess unique phylogeny, geographical origins and traits, making their genome structure of great interest. The increasing number of available canid reference genomes allows us to examine the impact the choice of reference genome makes with regard to reference genome quality and breed relatedness. RESULTS: Here, we report two high quality de novo Basenji genome assemblies: a female, China (CanFam_Bas), and a male, Wags. We conduct pairwise comparisons and report structural variations between assembled genomes of three dog breeds: Basenji (CanFam_Bas), Boxer (CanFam3.1) and German Shepherd Dog (GSD) (CanFam_GSD). CanFam_Bas is superior to CanFam3.1 in terms of genome contiguity and comparable overall to the high quality CanFam_GSD assembly. By aligning short read data from 58 representative dog breeds to three reference genomes, we demonstrate how the choice of reference genome significantly impacts both read mapping and variant detection. CONCLUSIONS: The growing number of high-quality canid reference genomes means the choice of reference genome is an increasingly critical decision in subsequent canid variant analyses. The basal position of the Basenji makes it suitable for variant analysis for targeted applications of specific dog breeds. However, we believe more comprehensive analyses across the entire family of canids is more suited to a pangenome approach. Collectively this work highlights the importance the choice of reference genome makes in all variation studies.


Assuntos
Lobos , Animais , China , Cromossomos , Cães , Feminino , Genoma , Genômica , Masculino , Lobos/genética
19.
J Hepatol ; 75(6): 1409-1419, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34437910

RESUMO

BACKGROUND & AIMS: Management of long-term immunosuppression following liver transplantation (LT) remains empirical. Surveillance liver biopsies in combination with transcriptional profiling could overcome this challenge by identifying recipients with active alloimmune-mediated liver damage despite normal liver tests, but this approach lacks applicability. Our aim was to investigate the utility of non-invasive tools for the stratification of stable long-term survivors of LT, according to their immunological risk and need for immunosuppression. METHODS: We conducted a cross-sectional multicentre study of 190 adult LT recipients assessed to determine their eligibility to participate in an immunosuppression withdrawal trial. Patients had stable liver allograft function and had been transplanted for non-autoimmune non-replicative viral liver disease >3 years before inclusion. We performed histological, immunogenetic and serological studies and measured the intrahepatic transcript levels of an 11-gene classifier highly specific for T cell-mediated rejection (TCMR). RESULTS: In this cohort, 35.8% of patients harboured clinically silent fibro-inflammatory liver lesions (13.7% had mild damage and 22.1% had moderate-to-severe damage). The severity of liver allograft damage was positively associated with TCMR-related transcripts, class II donor-specific antibodies (DSAs), ALT, AST, and liver stiffness measurement (LSM), and negatively correlated with serum creatinine and tacrolimus trough levels. Liver biopsies were stratified according to their TCMR transcript levels using a cut-off derived from biopsies with clinically significant TCMR. Two multivariable prediction models, integrating ALT+LSM or ALT+class II DSAs, had a high discriminative capacity for classifying patients with or without alloimmune damage. The latter model performed well in an independent cohort of 156 liver biopsies obtained from paediatric liver recipients with similar inclusion/exclusion criteria. CONCLUSION: ALT, class II DSAs and LSM are valuable tools to non-invasively identify stable LT recipients without significant underlying alloimmunity who could benefit from minimisation of immunosuppression. LAY SUMMARY: A large proportion of liver transplant patients with normal liver tests have inflammatory liver lesions, which in 17% of cases are molecularly indistinguishable from those seen at the time of rejection. ALT, class II donor-specific antibodies and liver stiffness are useful in identifying patients with this form of subclinical rejection. We propose these markers as a useful tool to help clinicians determine if the immunosuppression administered is adequate.


Assuntos
Hemocromatose/diagnóstico , Transplante de Fígado/efeitos adversos , Medição de Risco/normas , Adulto , Idoso , Biópsia/métodos , Biópsia/estatística & dados numéricos , Estudos Transversais , Feminino , Hemocromatose/epidemiologia , Humanos , Transplante de Fígado/métodos , Transplante de Fígado/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Tolerância ao Transplante
20.
Lancet ; 395(10219): 226-239, 2020 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-31791690

RESUMO

This final report of the Lancet Commission into liver disease in the UK stresses the continuing increase in burden of liver disease from excess alcohol consumption and obesity, with high levels of hospital admissions which are worsening in deprived areas. Only with comprehensive food and alcohol strategies based on fiscal and regulatory measures (including a minimum unit price for alcohol, the alcohol duty escalator, and an extension of the sugar levy on food content) can the disease burden be curtailed. Following introduction of minimum unit pricing in Scotland, alcohol sales fell by 3%, with the greatest effect on heavy drinkers of low-cost alcohol products. We also discuss the major contribution of obesity and alcohol to the ten most common cancers as well as measures outlined by the departing Chief Medical Officer to combat rising levels of obesity-the highest of any country in the west. Mortality of severely ill patients with liver disease in district general hospitals is unacceptably high, indicating the need to develop a masterplan for improving hospital care. We propose a plan based around specialist hospital centres that are linked to district general hospitals by operational delivery networks. This plan has received strong backing from the British Association for Study of the Liver and British Society of Gastroenterology, but is held up at NHS England. The value of so-called day-case care bundles to reduce high hospital readmission rates with greater care in the community is described, along with examples of locally derived schemes for the early detection of disease and, in particular, schemes to allow general practitioners to refer patients directly for elastography assessment. New funding arrangements for general practitioners will be required if these proposals are to be taken up more widely around the country. Understanding of the harm to health from lifestyle causes among the general population is low, with a poor knowledge of alcohol consumption and dietary guidelines. The Lancet Commission has serious doubts about whether the initiatives described in the Prevention Green Paper, with the onus placed on the individual based on the use of information technology and the latest in behavioural science, will be effective. We call for greater coordination between official and non-official bodies that have highlighted the unacceptable disease burden from liver disease in England in order to present a single, strong voice to the higher echelons of government.


Assuntos
Alcoolismo/epidemiologia , Hepatopatias/epidemiologia , Hepatopatias/prevenção & controle , Obesidade/epidemiologia , Bebidas Alcoólicas/economia , Alcoolismo/complicações , Alcoolismo/terapia , Comércio , Redes Comunitárias/organização & administração , Comorbidade , Efeitos Psicossociais da Doença , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Legislação sobre Alimentos , Hepatopatias/diagnóstico , Hepatopatias/etiologia , Transplante de Fígado/estatística & dados numéricos , Obesidade/complicações , Pacotes de Assistência ao Paciente , Escócia , Reino Unido/epidemiologia
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