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1.
Cell ; 164(1-2): 81-90, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26748718

RESUMO

MicroRNA maturation is initiated by RNase III DROSHA that cleaves the stem loop of primary microRNA. DROSHA functions together with its cofactor DGCR8 in a heterotrimeric complex known as Microprocessor. Here, we report the X-ray structure of DROSHA in complex with the C-terminal helix of DGCR8. We find that DROSHA contains two DGCR8-binding sites, one on each RNase III domain (RIIID), which mediate the assembly of Microprocessor. The overall structure of DROSHA is surprisingly similar to that of Dicer despite no sequence homology apart from the C-terminal part, suggesting that DROSHA may have evolved from a Dicer homolog. DROSHA exhibits unique features, including non-canonical zinc-finger motifs, a long insertion in the first RIIID, and the kinked link between Connector helix and RIIID, which explains the 11-bp-measuring "ruler" activity of DROSHA. Our study implicates the evolutionary origin of DROSHA and elucidates the molecular basis of Microprocessor assembly and primary microRNA processing.


Assuntos
MicroRNAs/metabolismo , Processamento Pós-Transcricional do RNA , Ribonuclease III/química , Sequência de Aminoácidos , Cristalografia por Raios X , RNA Helicases DEAD-box/química , RNA Helicases DEAD-box/metabolismo , Evolução Molecular , Humanos , MicroRNAs/química , Modelos Químicos , Modelos Moleculares , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Dobramento de Proteína , Estrutura Terciária de Proteína , Proteínas de Ligação a RNA/metabolismo , Ribonuclease III/genética , Ribonuclease III/metabolismo , Alinhamento de Sequência , Homologia Estrutural de Proteína
2.
Mol Cell ; 83(11): 1810-1826.e8, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37267903

RESUMO

Microprocessor (MP), DROSHA-DGCR8, processes primary miRNA transcripts (pri-miRNAs) to initiate miRNA biogenesis. The canonical cleavage mechanism of MP has been extensively investigated and comprehensively validated for two decades. However, this canonical mechanism cannot account for the processing of certain pri-miRNAs in animals. In this study, by conducting high-throughput pri-miRNA cleavage assays for approximately 260,000 pri-miRNA sequences, we discovered and comprehensively characterized a noncanonical cleavage mechanism of MP. This noncanonical mechanism does not need several RNA and protein elements essential for the canonical mechanism; instead, it utilizes previously unrecognized DROSHA dsRNA recognition sites (DRESs). Interestingly, the noncanonical mechanism is conserved across animals and plays a particularly significant role in C. elegans. Our established noncanonical mechanism elucidates MP cleavage in numerous RNA substrates unaccounted for by the canonical mechanism in animals. This study suggests a broader substrate repertoire of animal MPs and an expanded regulatory landscape for miRNA biogenesis.


Assuntos
MicroRNAs , Animais , MicroRNAs/metabolismo , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Ligação a RNA/metabolismo , Ribonuclease III/metabolismo , RNA de Cadeia Dupla , Processamento Pós-Transcricional do RNA
3.
Cell ; 161(6): 1374-87, 2015 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-26027739

RESUMO

MicroRNA (miRNA) maturation is initiated by Microprocessor composed of RNase III DROSHA and its cofactor DGCR8, whose fidelity is critical for generation of functional miRNAs. To understand how Microprocessor recognizes pri-miRNAs, we here reconstitute human Microprocessor with purified recombinant proteins. We find that Microprocessor is an ∼364 kDa heterotrimeric complex of one DROSHA and two DGCR8 molecules. Together with a 23-amino acid peptide from DGCR8, DROSHA constitutes a minimal functional core. DROSHA serves as a "ruler" by measuring 11 bp from the basal ssRNA-dsRNA junction. DGCR8 interacts with the stem and apical elements through its dsRNA-binding domains and RNA-binding heme domain, respectively, allowing efficient and accurate processing. DROSHA and DGCR8, respectively, recognize the basal UG and apical UGU motifs, which ensure proper orientation of the complex. These findings clarify controversies over the action mechanism of DROSHA and allow us to build a general model for pri-miRNA processing.


Assuntos
MicroRNAs/metabolismo , Processamento Pós-Transcricional do RNA , Proteínas de Ligação a RNA/química , Ribonuclease III/química , Sequência de Bases , Dimerização , Humanos , MicroRNAs/genética , Dados de Sequência Molecular , Motivos de Nucleotídeos , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Ribonuclease III/genética , Ribonuclease III/metabolismo
4.
Nucleic Acids Res ; 52(4): 1860-1877, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38167721

RESUMO

In humans, DICER is a key regulator of gene expression through its production of miRNAs and siRNAs by processing miRNA precursors (pre-miRNAs), short-hairpin RNAs (shRNAs), and long double-stranded RNAs (dsRNAs). To advance our understanding of this process, we employed high-throughput dicing assays using various shRNA variants and both wild-type and mutant DICER. Our analysis revealed that DICER predominantly cleaves shRNAs at two positions, specifically at 21 (DC21) and 22 (DC22) nucleotides from their 5'-end. Our investigation identified two different motifs, mWCU and YCR, that determine whether DICER cleaves at DC21 or DC22, depending on their locations in shRNAs/pre-miRNAs. These motifs can work together or independently to determine the cleavage sites of DICER. Furthermore, our findings indicate that dsRNA-binding domain (dsRBD) of DICER enhances its cleavage, and mWCU strengthens the interaction between dsRBD and RNA, leading to an even greater enhancement of the cleavage. Conversely, YCR functions independently of dsRBD. Our study proposes a two-motif model that sheds light on the intricate regulatory mechanisms involved in gene expression by elucidating how DICER recognizes its substrates, providing valuable insights into this critical biological process.


Assuntos
MicroRNAs , Humanos , MicroRNAs/metabolismo , Ribonuclease III/metabolismo , RNA de Cadeia Dupla/genética , RNA Interferente Pequeno/genética
5.
Nucleic Acids Res ; 51(4): 1512-1527, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36598924

RESUMO

Microprocessor (MP) is a complex involved in initiating the biogenesis of microRNAs (miRNAs) by cleaving primary microRNAs (pri-miRNAs). miRNAs are small single-stranded RNAs that play a key role in the post-transcriptional regulation of gene expression. Thus, understanding the molecular mechanism of MP is critical for interpreting the roles of miRNAs in normal cellular processes and during the onset of various diseases. MP comprises a ribonuclease enzyme, DROSHA, and a dimeric RNA-binding protein, which is called DGCR8 in humans and Pasha in Caenorhabditis elegans. DROSHA cleaves stem-loop structures located within pri-miRNAs to generate pre-miRNAs. Although the molecular mechanism of human MP (hMP; hDROSHA-DGCR8) is well understood, that of Caenorhabditis elegans MP (cMP; cDrosha-Pasha) is still largely unknown. Here, we reveal the molecular mechanism of cMP and show that it is distinct from that of hMP. We demonstrate that cDrosha and Pasha measure ∼16 and ∼25 bp along a pri-miRNA stem, respectively, and they work together to determine the site of cMP cleavage in pri-miRNAs. We also demonstrate the molecular basis for their substrate measurement. Thus, our findings reveal a previously unknown molecular mechanism of cMP; demonstrate the differences between the mechanisms of hMP and cMP; and provide a foundation for revealing the mechanisms regulating miRNA expression in different animal species.


The Microprocessor complex that initiates miRNA biogenesis was discovered in animals in 2004. However, the molecular mechanism of C. elegans Microprocessor (cMP) has remained elusive since its discovery 18 years ago. In this study, we revealed the unique molecular mechanism of cMP by conducting high-throughput pri-miRNA cleavage assays. We demonstrated that cMP, consisting of cDrosha and Pasha, each can measure the stem lengths of pri-miRNAs. cDrosha measures ∼16 bp of the lower stem length, whereas Pasha measures ∼25 bp of the upper stem in pri-miRNAs. In addition, we identified the cleavage sites and cleavage efficiency of cMP in C. elegans pri-miRNAs. These results will be helpful for future studies of miRNA biogenesis in C. elegans.


Assuntos
Caenorhabditis elegans , MicroRNAs , Proteínas de Ligação a RNA , Animais , Humanos , Caenorhabditis elegans/química , Caenorhabditis elegans/metabolismo , Regulação da Expressão Gênica , MicroRNAs/genética , Ribonuclease III/metabolismo , Processamento Pós-Transcricional do RNA , Proteínas de Ligação a RNA/metabolismo
6.
Emerg Infect Dis ; 30(5): 991-994, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38666642

RESUMO

African swine fever virus (ASFV) genotype II is endemic to Vietnam. We detected recombinant ASFV genotypes I and II (rASFV I/II) strains in domestic pigs from 6 northern provinces in Vietnam. The introduction of rASFV I/II strains could complicate ongoing ASFV control measures in the region.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Genótipo , Filogenia , Animais , Vírus da Febre Suína Africana/genética , Vírus da Febre Suína Africana/classificação , Vietnã/epidemiologia , Febre Suína Africana/epidemiologia , Febre Suína Africana/virologia , Suínos , Sus scrofa/virologia , Recombinação Genética
7.
RNA ; 28(7): 1028-1038, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35487691

RESUMO

Hairpin-containing pre-miRNAs, produced from pri-miRNAs, are precursors of miRNAs (microRNAs) that play essential roles in gene expression and various human diseases. Current qPCR-based methods used to quantify pre-miRNAs are not effective to discriminate between pre-miRNAs and their parental pri-miRNAs. Here, we developed the intramolecular ligation method (iLIME) to quantify and sequence pre-miRNAs specifically. This method utilizes T4 RNA ligase 1 to convert pre-miRNAs into circularized RNAs, allowing us to design PCR primers to quantify pre-miRNAs, but not their parental pri-miRNAs. In addition, the iLIME also enables us to sequence the ends of pre-miRNAs using next-generation sequencing. Therefore, this method offers a simple and effective way to quantify and sequence pre-miRNAs, so it will be highly beneficial for investigating pre-miRNAs when addressing research questions and medical applications.


Assuntos
MicroRNAs , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , MicroRNAs/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
8.
AIDS Care ; 36(5): 631-640, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37339000

RESUMO

The Human Immunodeficiency Virus (HIV) epidemic remains a major public health issue worldwide. In Vietnam, the HIV epidemic is essentially driven by people who inject drugs (PWID). This study aims to compare mortality and loss to follow-up (LTFU) between PWID and other patients. From June 2017 to April 2018, HIV-infected adults were enrolled in a prospective cohort from time of ART initiation in six provinces of North Vietnam. The end date was July 2020. Mortality and LTFU were described using competing-risk survival models. Factors associated with mortality and with LTFU were identified using Cox models with a competing-risk approach. Of the 578 participants, 261 (45.2%) were PWID and almost exclusively male. 49 patients died, corresponding to a mortality rate (95% confidence interval (CI)) of 3.7 (2.8-4.9) per 100 person-months, and 79 were lost to follow-up, corresponding to a rate (95% CI) of 6.0 (4.8-7.4) per 100 person-months. PWID were at higher risk of death but not of LTFU. Overall, LTFU was high in both groups. Latecomers to clinical visits were more at risk of both death and LTFU. Therefore, this should be a warning to clinical teams and preventive actions taken in these patients.Trial registration: ClinicalTrials.gov identifier: NCT03249493..


Assuntos
Infecções por HIV , Abuso de Substâncias por Via Intravenosa , Adulto , Humanos , Masculino , HIV , Infecções por HIV/epidemiologia , Incidência , Perda de Seguimento , Estudos Prospectivos , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/epidemiologia , Vietnã/epidemiologia , Feminino
9.
J Biomed Inform ; 156: 104673, 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38862083

RESUMO

OBJECTIVE: Pneumothorax is an acute thoracic disease caused by abnormal air collection between the lungs and chest wall. Recently, artificial intelligence (AI), especially deep learning (DL), has been increasingly employed for automating the diagnostic process of pneumothorax. To address the opaqueness often associated with DL models, explainable artificial intelligence (XAI) methods have been introduced to outline regions related to pneumothorax. However, these explanations sometimes diverge from actual lesion areas, highlighting the need for further improvement. METHOD: We propose a template-guided approach to incorporate the clinical knowledge of pneumothorax into model explanations generated by XAI methods, thereby enhancing the quality of the explanations. Utilizing one lesion delineation created by radiologists, our approach first generates a template that represents potential areas of pneumothorax occurrence. This template is then superimposed on model explanations to filter out extraneous explanations that fall outside the template's boundaries. To validate its efficacy, we carried out a comparative analysis of three XAI methods (Saliency Map, Grad-CAM, and Integrated Gradients) with and without our template guidance when explaining two DL models (VGG-19 and ResNet-50) in two real-world datasets (SIIM-ACR and ChestX-Det). RESULTS: The proposed approach consistently improved baseline XAI methods across twelve benchmark scenarios built on three XAI methods, two DL models, and two datasets. The average incremental percentages, calculated by the performance improvements over the baseline performance, were 97.8% in Intersection over Union (IoU) and 94.1% in Dice Similarity Coefficient (DSC) when comparing model explanations and ground-truth lesion areas. We further visualized baseline and template-guided model explanations on radiographs to showcase the performance of our approach. CONCLUSIONS: In the context of pneumothorax diagnoses, we proposed a template-guided approach for improving model explanations. Our approach not only aligns model explanations more closely with clinical insights but also exhibits extensibility to other thoracic diseases. We anticipate that our template guidance will forge a novel approach to elucidating AI models by integrating clinical domain expertise.

10.
BMC Health Serv Res ; 24(1): 156, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302993

RESUMO

BACKGROUND: As Vietnam and other low- and middle-income countries (LMIC) experience a rapid increase in the number of people living with dementia, an acute need exists to strengthen research capacity to inform policy, improve care and support, and develop national dementia plans. We describe the development and early outcomes of an National Institutes of Health (NIH)/National Institute on Aging (NIA)-funded national dementia research capacity building program in Vietnam. METHODS: The research capacity building program commenced in 2019 and has three components: (1) Vietnam Alzheimer's and other dementias research Network (VAN), (2) a mentored pilot grant program, and (3) research training, networking, and dissemination activities. The pilot grant program funds Vietnamese researchers for one to two years to conduct research focusing on Alzheimer's Disease and Alzheimer's Disease Related Dementias (AD/ADRD). Grants are reviewed and scored using NIH criteria, and priority is given to pilot grants with policy relevance and potential for future funding. An international pool of high-income country (e.g., United States, Australia, and United Kingdom) mentors has been engaged and mentors paired with each funded project. Training and networking activities include workshops on AD/ADRD research topics and regular meetings in conjunction with Vietnam's annual national dementia/geriatric conferences. Dissemination is facilitated through targeted outreach and the creation of a national network of institutions. RESULTS: Over four years (2019-2023), we received 62 applications, reviewed 58 applications, and funded 21 projects (4-5 per year). Funded investigators were from diverse disciplines and institutions across Vietnam with projects on a range of topics, including biomarkers, prevention, diagnosis, neuropsychological assessment, family caregiver support, dementia education, and clinical trials. A network of 12 leading academic and research institutions nationwide has been created to facilitate dissemination. Six research training workshops have been organized and included presentations from international speakers. Grantees have published or presented their studies at both national and international levels. The mentoring program has helped grantees to build their research skills and expand their research network. CONCLUSION: This research capacity building program is the first of its kind in Vietnam and may serve as a useful model for other LMIC.


Assuntos
Doença de Alzheimer , Tutoria , Humanos , Estados Unidos , Idoso , Vietnã , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/terapia , Mentores , Cuidadores
11.
BMC Health Serv Res ; 24(1): 86, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233921

RESUMO

BACKGROUND: Dementia is a global public health priority. The World Health Organization adopted a Global Action Plan on Dementia, with dementia awareness a priority. This study examined the knowledge, attitudes, and self-confidence with skills required for providing dementia care among primary health care providers in Vietnam. METHODS: A cross-sectional study was conducted with 405 primary health care providers who worked at commune health stations and district health centers in eight provinces across Vietnam. RESULTS: The results showed that primary health care providers had poor knowledge and little confidence but more positive attitudes toward dementia care and management. CONCLUSIONS: The results suggest the training needs for building capacity amongst primary health care providers, which will be critical as Vietnam's population ages.


Assuntos
Demência , Médicos , Humanos , Conhecimentos, Atitudes e Prática em Saúde , Vietnã , Estudos Transversais , Atenção Primária à Saúde , Demência/terapia
12.
BMC Health Serv Res ; 24(1): 151, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291402

RESUMO

BACKGROUND: Inpatient rehabilitation services are challenged by increasing demand. Where appropriate, a shift in service models towards more community-oriented approaches may improve efficiency. We aimed to estimate the hypothetical cost of delivering a consensus-based rehabilitation in the home (RITH) model as hospital substitution for patients requiring reconditioning following medical illness, surgery or treatment for cancer, compared to the cost of inpatient rehabilitation. METHODS: Data were drawn from the following sources: the results of a Delphi survey with health professionals working in the field of rehabilitation in Australia; publicly available data and reports; and the expert opinion of the project team. Delphi survey data were analysed descriptively. The costing model was developed using assumptions based on the sources described above and was restricted to the Australian National Subacute and Non-Acute Patient Classification (AN-SNAP) classes 4AR1 to 4AR4, which comprise around 73% of all reconditioning episodes in Australia. RITH cost modelling estimates were compared to the known cost of inpatient rehabilitation. Where weighted averages are provided, these were determined based on the modelled number of inpatient reconditioning episodes per annum that might be substitutable by RITH. RESULTS: The cost modelling estimated the weighted average cost of a RITH reconditioning episode (which mirrors an inpatient reconditioning episode in intensity and duration) for AN-SNAP classes 4AR1 to 4AR4, to be A$11,371, which is 28.1% less than the equivalent weighted average public inpatient cost (of A$15,820). This represents hypothetical savings of A$4,449 per RITH reconditioning substituted episode of care. CONCLUSIONS: The hypothetical cost of a model of RITH which would provide patients with as comprehensive a rehabilitation service as received in inpatient rehabilitation, has been determined. Findings suggest potential cost savings to the public hospital sector. Future research should focus on trials which compare actual clinical and cost outcomes of RITH for patients in the reconditioning impairment category, to inpatient rehabilitation.


Assuntos
Pacientes Internados , Humanos , Austrália , Previsões
13.
J Biol Chem ; 298(12): 102677, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36336075

RESUMO

Cytokines of the interleukin 12 (IL-12) family are assembled combinatorially from shared α and ß subunits. A common theme is that human IL-12 family α subunits remain incompletely structured in isolation until they pair with a designate ß subunit. Accordingly, chaperones need to support and control specific assembly processes. It remains incompletely understood, which chaperones are involved in IL-12 family biogenesis. Here, we site-specifically introduce photocrosslinking amino acids into the IL-12 and IL-23 α subunits (IL-12α and IL-23α) for stabilization of transient chaperone-client complexes for mass spectrometry. Our analysis reveals that a large set of endoplasmic reticulum chaperones interacts with IL-12α and IL-23α. Among these chaperones, we focus on protein disulfide isomerase (PDI) family members and reveal IL-12 family subunits to be clients of several incompletely characterized PDIs. We find that different PDIs show selectivity for different cysteines in IL-12α and IL-23α. Despite this, PDI binding generally stabilizes unassembled IL-12α and IL-23α against degradation. In contrast, α:ß assembly appears robust, and only multiple simultaneous PDI depletions reduce IL-12 secretion. Our comprehensive analysis of the IL-12/IL-23 chaperone machinery reveals a hitherto uncharacterized role for several PDIs in this process. This extends our understanding of how cells accomplish the task of specific protein assembly reactions for signaling processes. Furthermore, our findings show that cytokine secretion can be modulated by targeting specific endoplasmic reticulum chaperones.


Assuntos
Citocinas , Isomerases de Dissulfetos de Proteínas , Humanos , Interleucina-12 , Interleucina-23 , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Isomerases de Dissulfetos de Proteínas/metabolismo , Dobramento de Proteína , Retículo Endoplasmático
14.
Int J Geriatr Psychiatry ; 38(7): e5965, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37430439

RESUMO

OBJECTIVES: More people with dementia live in low- and middle-income countries (LMICs) than in high-income countries, but best-practice care recommendations are often based on studies from high-income countries. We aimed to map the available evidence on dementia interventions in LMICs. METHODS: We systematically mapped available evidence on interventions that aimed to improve the lives of people with dementia or mild cognitive impairment (MCI) and/or their carers in LMICs (registered on PROSPERO: CRD42018106206). We included randomised controlled trials (RCTs) published between 2008 and 2018. We searched 11 electronic academic and grey literature databases (MEDLINE, EMBASE, PsycINFO, CINAHL Plus, Global Health, World Health Organization Global Index Medicus, Virtual Health Library, Cochrane CENTRAL, Social Care Online, BASE, MODEM Toolkit) and examined the number and characteristics of RCTs according to intervention type. We used the Cochrane risk of bias 2.0 tool to assess the risk of bias. RESULTS: We included 340 RCTs with 29,882 (median, 68) participants, published 2008-2018. Over two-thirds of the studies were conducted in China (n = 237, 69.7%). Ten LMICs accounted for 95.9% of included RCTs. The largest category of interventions was Traditional Chinese Medicine (n = 149, 43.8%), followed by Western medicine pharmaceuticals (n = 109, 32.1%), supplements (n = 43, 12.6%), and structured therapeutic psychosocial interventions (n = 37, 10.9%). Overall risk of bias was judged to be high for 201 RCTs (59.1%), moderate for 136 (40.0%), and low for 3 (0.9%). CONCLUSIONS: Evidence-generation on interventions for people with dementia or MCI and/or their carers in LMICs is concentrated in just a few countries, with no RCTs reported in the vast majority of LMICs. The body of evidence is skewed towards selected interventions and overall subject to high risk of bias. There is a need for a more coordinated approach to robust evidence-generation for LMICs.


Assuntos
Disfunção Cognitiva , Demência , Humanos , China , Disfunção Cognitiva/terapia , Bases de Dados Factuais , Demência/terapia , Países em Desenvolvimento , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
Nucleic Acids Res ; 49(11): e62, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-33684219

RESUMO

The genetic code of mammalian cells can be expanded to allow the incorporation of non-canonical amino acids (ncAAs) by suppressing in-frame amber stop codons (UAG) with an orthogonal pyrrolysyl-tRNA synthetase (PylRS)/tRNAPylCUA (PylT) pair. However, the feasibility of this approach is substantially hampered by unpredictable variations in incorporation efficiencies at different stop codon positions within target proteins. Here, we apply a proteomics-based approach to quantify ncAA incorporation rates at hundreds of endogenous amber stop codons in mammalian cells. With these data, we compute iPASS (Identification of Permissive Amber Sites for Suppression; available at www.bultmannlab.eu/tools/iPASS), a linear regression model to predict relative ncAA incorporation efficiencies depending on the surrounding sequence context. To verify iPASS, we develop a dual-fluorescence reporter for high-throughput flow-cytometry analysis that reproducibly yields context-specific ncAA incorporation efficiencies. We show that nucleotides up- and downstream of UAG synergistically influence ncAA incorporation efficiency independent of cell line and ncAA identity. Additionally, we demonstrate iPASS-guided optimization of ncAA incorporation rates by synonymous exchange of codons flanking the amber stop codon. This combination of in silico analysis followed by validation in living mammalian cells substantially simplifies identification as well as adaptation of sites within a target protein to confer high ncAA incorporation rates.


Assuntos
Aminoácidos/metabolismo , Código Genético , Animais , Linhagem Celular , Códon , Códon de Terminação , Simulação por Computador , Células-Tronco Embrionárias/metabolismo , Citometria de Fluxo , Genes Reporter , Células HEK293 , Humanos , Modelos Lineares , Camundongos , Mutação , Proteômica
16.
BMC Health Serv Res ; 23(1): 113, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36737750

RESUMO

BACKGROUND: Reconditioning for patients who have experienced functional decline following medical illness, surgery or treatment for cancer accounts for approximately 26% of all reported inpatient rehabilitation episodes in Australia. Rehabilitation in the home (RITH) has the potential to offer a cost-effective, high-quality alternative for appropriate patients, helping to reduce pressure on the acute care sector. This study sought to gain consensus on a model for RITH as hospital substitution for patients requiring reconditioning. METHODS: A multidisciplinary group of health professionals working in the rehabilitation field was identified from across Australia and invited to participate in a three-round online Delphi survey. Survey items followed the patient journey, and also included items on practitioner roles, clinical governance, and budgetary considerations. Survey items mostly comprised statements seeking agreement on 5-point Likert scales (strongly agree to strongly disagree). Free text boxes allowed participants to qualify item answers or make comments. Analysis of quantitative data used descriptive statistics; qualitative data informed question content in subsequent survey rounds or were used in understanding item responses. RESULTS: One-hundred and ninety-eight health professionals received an invitation to participate. Of these, 131/198 (66%) completed round 1, 101/131 (77%) completed round 2, and 78/101 (77%) completed round 3. Consensus (defined as ≥ 70% agreement or disagreement) was achieved on over 130 statements. These related to the RITH patient journey (including patient assessment and development of the care plan, case management and program provision, and patient and program outcomes); clinical governance and budgetary considerations; and included items for initial patient screening, patient eligibility and case manager roles. A consensus-based model for RITH was developed, comprising five key steps and the actions within each. CONCLUSIONS: Strong support amongst survey participants was found for RITH as hospital substitution to be widely available for appropriate patients needing reconditioning. Supportive legislative and payment systems, mechanisms that allow for the integration of primary care, and appropriate clinical governance frameworks for RITH are required, if broad implementation is to be achieved. Studies comparing clinical outcomes and cost-benefit of RITH to inpatient rehabilitation for patients requiring reconditioning are also needed.


Assuntos
Pessoal de Saúde , Hospitais , Reabilitação , Humanos , Austrália , Consenso , Técnica Delphi , Inquéritos e Questionários
17.
J Med Internet Res ; 25: e43224, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-37018013

RESUMO

BACKGROUND: A rapidly aging population, a shifting disease burden and the ongoing threat of infectious disease outbreaks pose major concerns for Vietnam's health care system. Health disparities are evident in many parts of the country, especially in rural areas, and the population faces inequitable access to patient-centered health care. Vietnam must therefore explore and implement advanced solutions to the provision of patient-centered care, with a view to reducing pressures on the health care system simultaneously. The use of digital health technologies (DHTs) may be one of these solutions. OBJECTIVE: This study aimed to identify the application of DHTs to support the provision of patient-centered care in low- and middle-income countries in the Asia-Pacific region (APR) and to draw lessons for Vietnam. METHODS: A scoping review was undertaken. Systematic searches of 7 databases were conducted in January 2022 to identify publications on DHTs and patient-centered care in the APR. Thematic analysis was conducted, and DHTs were classified using the National Institute for Health and Care Excellence evidence standards framework for DHTs (tiers A, B, and C). Reporting was in line with the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews) guidelines. RESULTS: Of the 264 publications identified, 45 (17%) met the inclusion criteria. The majority of the DHTs were classified as tier C (15/33, 45%), followed by tier B (14/33, 42%) and tier A (4/33, 12%). At an individual level, DHTs increased accessibility of health care and health-related information, supported individuals in self-management, and led to improvements in clinical and quality-of-life outcomes. At a systems level, DHTs supported patient-centered outcomes by increasing efficiency, reducing strain on health care resources, and supporting patient-centered clinical practice. The most frequently reported enablers for the use of DHTs for patient-centered care included alignment of DHTs with users' individual needs, ease of use, availability of direct support from health care professionals, provision of technical support as well as user education and training, appropriate governance of privacy and security, and cross-sectorial collaboration. Common barriers included low user literacy and digital literacy, limited user access to DHT infrastructure, and a lack of policies and protocols to guide the implementation and use of DHTs. CONCLUSIONS: The use of DHTs is a viable option to increase equitable access to quality, patient-centered care across Vietnam and simultaneously reduce pressures on the health care system. Vietnam can take advantage of the lessons learned by other low- and middle-income countries in the APR when developing a national road map to digital health transformation. Recommendations that Vietnamese policy makers may consider include emphasizing stakeholder engagement, strengthening digital literacy, supporting the improvement of DHT infrastructure, increasing cross-sectorial collaboration, strengthening governance of cybersecurity, and leading the way in DHT uptake.


Assuntos
Países em Desenvolvimento , Tecnologia Digital , Idoso , Humanos , Ásia , Assistência Centrada no Paciente , Vietnã
18.
Aging Ment Health ; 27(2): 301-316, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35549573

RESUMO

Objectives: This paper aimed to review and synthesise the qualitative research evidence on the experiences and perceptions of dementia in Vietnam and among the Vietnamese diaspora.Methods: Systematic searches were conducted in June 2019 using Medline, Embase, Emcare, PsycINFO and Cochrane electronic databases, as well as grey literature. Keywords and Medical Subject Headings [MeSH terms] for dementia and associated terms were combined with keywords for Vietnam and its provinces. Qualitative research articles published in English or Vietnamese were included to examine evidence on the life experiences of Vietnamese people with dementia using thematic analysis.Results: Our searches resulted in 3,940 papers, from which 21 qualitative research studies were included for final analysis. The majority of research has not been undertaken in Vietnam but with the Vietnamese diaspora in Western countries and has taken a cultural perspective to analyses. Research in Western countries has focused on the need for culturally adapted and culturally sensitive models of care. Emerging themes about the life experiences of Vietnamese people with dementia identified from the studies included: many people do not have diagnostic terms for dementia but use the descriptive language of symptoms; stigma was a reported problem and on occasions can be observed in the descriptive language used for people with dementia; cultural and traditional values create both an opportunity and a barrier, supporting compassion, family care and relaxation, but creating barriers to accessing health services or long-term residential care.Conclusions: This is the first systematic review reporting qualitative evidence on the life experiences of people with dementia in Vietnam and among the Vietnamese diaspora. Future research is needed on the voice of people with dementia themselves and their caregivers particularly in Vietnam, and low and middle-income countries with regards to living with dementia, pathways to care from diagnosis, treatment, care and support, additional social care and preparedness for end of life care for people with dementia.


Assuntos
Demência , População do Sudeste Asiático , Humanos , Vietnã , Demência/terapia , Idioma , Pesquisa Qualitativa , Cuidadores
19.
Sensors (Basel) ; 23(23)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38067858

RESUMO

In the rapidly evolving urban advanced mobility (UAM) sphere, Vehicular Ad Hoc Networks (VANETs) are crucial for robust communication and operational efficiency in future urban environments. This paper quantifies VANETs to improve their reliability and availability, essential for integrating UAM into urban infrastructures. It proposes a novel Stochastic Petri Nets (SPN) method for evaluating VANET-based Vehicle Communication and Control (VCC) architectures, crucial given the dynamic demands of UAM. The SPN model, incorporating virtual machine (VM) migration and Edge Computing, addresses VANET integration challenges with Edge Computing. It uses stochastic elements to mirror VANET scenarios, enhancing network robustness and dependability, vital for the operational integrity of UAM. Case studies using this model offer insights into system availability and reliability, guiding VANET optimizations for UAM. The paper also applies a Design of Experiments (DoE) approach for a sensitivity analysis of SPN components, identifying key parameters affecting system availability. This is critical for refining the model for UAM efficiency. This research is significant for monitoring UAM systems in future cities, presenting a cost-effective framework over traditional methods and advancing VANET reliability and availability in urban mobility contexts.

20.
RNA ; 26(12): 1777-1786, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32994184

RESUMO

The Microprocessor complex of DROSHA and DGCR8 initiates the biosynthesis of microRNAs (miRNAs) by processing primary miRNAs (pri-miRNAs). The Microprocessor can be oriented on pri-miRNAs in opposite directions to generate productive and unproductive cleavages at their basal and apical junctions, respectively. However, only the productive cleavage gives rise to miRNAs. A single nucleotide polymorphism (SNP, rs2910164) in pri-mir-146a is associated with various human diseases. Although this SNP was found to reduce the expression of miRNA, it is still not known if it affects the activity of the Microprocessor directly, and how it functions. In this study, we revealed that the SNP creates an unexpected mGHG motif at the apical junction of pri-mir-146a. This mGHG motif interacts with the double-stranded RNA-binding domain (dsRBD) of DROSHA, switching its orientation on pri-mir-146a from the basal to the apical junction. As a result, the SNP facilitates Microprocessor to cleave SNP-pri-mir-146a at its unproductive sites. Our findings help to elucidate the molecular mechanism that explains how the disease-associated SNP modulates the biogenesis of pri-mir-146a and thereby affects its cellular functions.


Assuntos
Doença/genética , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único , Processamento Pós-Transcricional do RNA , Ribonuclease III/química , Humanos , MicroRNAs/química , MicroRNAs/metabolismo , Ribonuclease III/metabolismo
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