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1.
Nature ; 633(8029): 465-472, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39143216

RESUMO

The newly identified type VII CRISPR-Cas candidate system uses a CRISPR RNA-guided ribonucleoprotein complex formed by Cas5 and Cas7 proteins to target RNA1. However, the RNA cleavage is executed by a dedicated Cas14 nuclease, which is distinct from the effector nucleases of the other CRISPR-Cas systems. Here we report seven cryo-electron microscopy structures of the Cas14-bound interference complex at different functional states. Cas14, a tetrameric protein in solution, is recruited to the Cas5-Cas7 complex in a target RNA-dependent manner. The N-terminal catalytic domain of Cas14 binds a stretch of the substrate RNA for cleavage, whereas the C-terminal domain is primarily responsible for tethering Cas14 to the Cas5-Cas7 complex. The biochemical cleavage assays corroborate the captured functional conformations, revealing that Cas14 binds to different sites on the Cas5-Cas7 complex to execute individual cleavage events. Notably, a plugged-in arginine of Cas7 sandwiched by a C-shaped clamp of C-terminal domain precisely modulates Cas14 binding. More interestingly, target RNA cleavage is altered by a complementary protospacer flanking sequence at the 5' end, but not at the 3' end. Altogether, our study elucidates critical molecular details underlying the assembly of the interference complex and substrate cleavage in the type VII CRISPR-Cas system, which may help rational engineering of the type VII CRISPR-Cas system for biotechnological applications.


Assuntos
Proteínas Associadas a CRISPR , Sistemas CRISPR-Cas , Domínio Catalítico , Microscopia Crioeletrônica , Arginina/metabolismo , Arginina/química , Proteínas Associadas a CRISPR/química , Proteínas Associadas a CRISPR/classificação , Proteínas Associadas a CRISPR/metabolismo , Proteínas Associadas a CRISPR/ultraestrutura , Modelos Moleculares , Ligação Proteica , Clivagem do RNA , RNA Guia de Sistemas CRISPR-Cas/química , RNA Guia de Sistemas CRISPR-Cas/metabolismo , RNA Guia de Sistemas CRISPR-Cas/ultraestrutura , Relação Estrutura-Atividade , Especificidade por Substrato , Multimerização Proteica
2.
Magn Reson Med ; 92(3): 1048-1063, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38725383

RESUMO

PURPOSE: To introduce a novel deep model-based architecture (DMBA), SPICER, that uses pairs of noisy and undersampled k-space measurements of the same object to jointly train a model for MRI reconstruction and automatic coil sensitivity estimation. METHODS: SPICER consists of two modules to simultaneously reconstructs accurate MR images and estimates high-quality coil sensitivity maps (CSMs). The first module, CSM estimation module, uses a convolutional neural network (CNN) to estimate CSMs from the raw measurements. The second module, DMBA-based MRI reconstruction module, forms reconstructed images from the input measurements and the estimated CSMs using both the physical measurement model and learned CNN prior. With the benefit of our self-supervised learning strategy, SPICER can be efficiently trained without any fully sampled reference data. RESULTS: We validate SPICER on both open-access datasets and experimentally collected data, showing that it can achieve state-of-the-art performance in highly accelerated data acquisition settings (up to 10 × $$ 10\times $$ ). Our results also highlight the importance of different modules of SPICER-including the DMBA, the CSM estimation, and the SPICER training loss-on the final performance of the method. Moreover, SPICER can estimate better CSMs than pre-estimation methods especially when the ACS data is limited. CONCLUSION: Despite being trained on noisy undersampled data, SPICER can reconstruct high-quality images and CSMs in highly undersampled settings, which outperforms other self-supervised learning methods and matches the performance of the well-known E2E-VarNet trained on fully sampled ground-truth data.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Imageamento por Ressonância Magnética/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Aprendizado de Máquina Supervisionado , Encéfalo/diagnóstico por imagem , Aprendizado Profundo , Imagens de Fantasmas
3.
J Med Virol ; 96(1): e29373, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38235541

RESUMO

The uncertainty and unknowability of emerging infectious diseases have caused many major public health and security incidents in recent years. As a new tick-borne disease, Dabieshan tick virus (DBTV) necessitate systematic epidemiological and spatial distribution analysis. In this study, tick samples from Liaoning Province were collected and used to evaluate distribution of DBTV in ticks. Outbreak points of DBTV and the records of the vector Haemaphysalis longicornis in China were collected and used to establish a prediction model using niche model combined with environmental factors. We found that H. longicornis and DBTV were widely distributed in Liaoning Province. The risk analysis results showed that the DBTV in the eastern provinces of China has a high risk, and the risk is greatly influenced by elevation, land cover, and meteorological factors. The risk geographical area predicted by the model is significantly larger than the detected positive areas, indicating that the etiological survey is seriously insufficient. This study provided molecular and important epidemiological evidence for etiological ecology of DBTV. The predicted high-risk areas indicated the insufficient monitoring and risk evaluation and the necessity of future monitoring and control work.


Assuntos
Doenças Transmitidas por Carrapatos , Carrapatos , Animais , Humanos , Haemaphysalis longicornis , Doenças Transmitidas por Carrapatos/epidemiologia , China/epidemiologia
4.
J Adv Nurs ; 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223032

RESUMO

OBJECTIVES: To synthesize family members' experiences and perspectives on advance care planning (ACP) in nursing homes. METHODS: The thematic synthesis is reported following the Enhancing Transparency in Reporting the Synthesis of Qualitative Research (ENTREQ) statement. A systematic search of the APA PsycINFO, CINAHL Plus, Embase and PubMed databases is initially conducted in October 2022, and the search is updated in January 2024. Qualitative studies that presented family members' quotes regarding advance care planning in nursing homes published in a peer-reviewed journal were included. Screening and data extraction were independently performed by two reviewers, and any discrepancies were resolved with the assistance of the third author. RESULTS: A total of 1027 articles were identified, and 23 articles were included in the full-text review. Subsequently, a total of 17 studies were ultimately included, and 127 quotes were extracted and analysed. The main findings were categorized into three themes: (1) invitation to conversation and care, (2) the resident's surrogate and (3) nurses. Considering the importance of family members' roles in ACP conversations in a nursing home setting, this study provided an in-depth understanding of family members' perceptions and experiences of ACP by synthesizing qualitative studies. Family members' lack of knowledge regarding the timing and pursuits of ACP was also identified. CONCLUSION: The findings of this study provide synthesized qualitative evidence of family members' perspectives on ACP, which can inform care and treatment in nursing homes. As this study synthesizes the experiences of family members in nursing homes about ACP, the findings of this study contribute to reflecting family members' experiences and providing evidence for nursing home healthcare professionals. PATIENT OR PUBLIC CONTRIBUTION: This study reports the experiences of family members in ACP nursing homes. The findings of this study contribute to reflecting family members' experiences and building evidence for nursing home healthcare professionals.

5.
J Clin Nurs ; 33(8): 3033-3055, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38764213

RESUMO

BACKGROUND: The purpose of this study is to examine and evaluate the existing clinical practice guidelines and consensus statements regarding tracheostomy care for non-mechanically ventilated patients. METHODS: A systematic search of databases, and professional organisations was conducted from inception to 19 March 2023. Two appraisers evaluated each guideline using the Appraisal of Guidelines for Research & Evaluation II (AGREE II) and the Joanna Briggs Institute (JBI) Critical Appraisal Checklist for Text and Opinion Papers. RESULTS: No specific clinical guidelines exist on airway management in non-mechanically ventilated patients. Of 6318 articles identified, we included 12 clinical practice guidelines, and 9 consensus statements, which were from China, the US, the UK, South Korea, Australia, France and Belgium. The AGREE II scores in six domains are (1) the scope and purpose, 70.30%; (2) stakeholder involvement, 37.61%; (3) rigor of development, 33.97%; (4) clarity of presentation, 68.16%; (5) applicability, 44.23% and (6) editorial independence, 40.06%. The overall quality of evidence was level B. The summarised recommendations for clinical practice encompass the following six areas: airway humidification, management of the trach cuff, management of inner cannula, tracheostoma care, tracheostomy suctioning and management and prevention of common post-operative complications. CONCLUSIONS: The overall quality of the clinical guidelines on non-ventilated tracheostomy care was moderate, and further improvements are needed in domains of stakeholder involvement, applicability, clarity of presentation and editorial independence. Recommendations on non-ventilated tracheostomy care are often embedded in the guidelines on ventilated tracheostomy. Specific clinical guidelines are needed to provide a standardised approach to tracheostomy care for non-ventilated patients. RELEVANCE TO CLINICAL PRACTICE: Patients with non-ventilated tracheostomy need specialised airway management. Improving patient outcomes requires standardised protocols, patient involvement, quality evaluation, and interdisciplinary approaches. NO PATIENT OR PUBLIC CONTRIBUTION: The study reviewed clinical practice guidelines and consensus statements, therefore patient or public input was not needed.


Assuntos
COVID-19 , Guias de Prática Clínica como Assunto , Traqueostomia , Humanos , Traqueostomia/normas , Consenso , SARS-CoV-2 , Manuseio das Vias Aéreas/normas , Manuseio das Vias Aéreas/métodos
6.
Women Health ; 64(2): 153-164, 2024 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-38267033

RESUMO

Up to 92 percent of Chinese women of reproductive age have pre-menstrual syndrome (PMS). The severe form of PMS (i.e. pre-menstrual dysphoric disorder [PMDD]) negatively affects women's everyday functioning and reproductive health. This study examined the relationships between menstrual, psychosocial characteristics and the risk of PMDD among young Chinese women. A cross-sectional online survey was conducted among Chinese university students in Hong Kong. Logistic regression was used to compute adjusted odds ratio (aOR) for the association of high-risk PMDD with menstrual and psychosocial characteristics. A total of 541 Chinese university students were recruited. Approximately 53 percent of female students were at high risk of developing PMDD. The high-risk PMDD group was significantly associated with a heavy volume of menstrual flow (aOR = 2.17, 95 percent CI 1.06-4.45), irregular menstrual cycle (1.72, 1.17-2.52), high dysmenorrhea (2.80, 1.95-4.04) and older ages of menarche (0.67, 0.45-0.98) in the menstrual characteristics. In the psychosocial characteristics, high-risk PMDD was significantly associated with symptoms of anxiety (2.19, 1.48-3.32) and depression (2.22, 1.48-3.32), high loneliness (1.94, 1.34-2.79) and low resilience (2.21, 1.52-3.23) levels. Additionally, resilience had a potential moderating effect on the associations between the high risk of PMDD and anxiety, depression and loneliness. The development and delivery of interventions that can enhance resilience and manage psychological distress would be beneficial for young Chinese women's reproductive health.


Assuntos
Transtorno Disfórico Pré-Menstrual , Síndrome Pré-Menstrual , Feminino , Humanos , Transtorno Disfórico Pré-Menstrual/epidemiologia , Transtorno Disfórico Pré-Menstrual/diagnóstico , Síndrome Pré-Menstrual/epidemiologia , Síndrome Pré-Menstrual/diagnóstico , Estudos Transversais , Universidades , Distúrbios Menstruais/complicações , Estudantes , Ciclo Menstrual
7.
AIDS Behav ; 27(5): 1486-1501, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36520336

RESUMO

Depressive symptoms can affect health outcomes in people living with HIV (PLWH) including adherence to treatment and disease prognosis. Self-management interventions targeting depressive symptoms have been effective in preventing these negative sequelae of depressive symptoms. The processes of self-management include learning skills related to living with the illness needs, accessing resources to manage the illness, and coping with the illness. A systematic literature review was conducted to appraise and synthesize the current evidence of self-management interventions targeting depressive symptoms in PLWH. Following the PRISMA guidelines, an electronic search of 4 databases was conducted. Original studies written in English that used a randomized controlled trial design to test the effect of self-management intervention on depressive symptoms were included. Studies were selected that were published on/before April 19, 2022, thus yielding 13 relevant articles. Risk of bias was assessed using the NIH Quality Assessment Tool for Controlled Intervention Studies and narrative synthesis was used to synthesize the results. 40 to 755 participants were included in the studies, with each using various measures to assess depressive symptoms pre-and post-intervention, and timepoints for assessing depressive symptoms post-intervention varied. While 12 studies showed a significant reduction in depressive symptoms post-intervention, only 4 studies that used individual coaching or technology showed lower depressive symptoms in intervention groups in comparison to the control groups. This review can be used to inform scale-up and dissemination of these interventions to improve depressive symptoms in PLWH.


RESUMEN: Los síntomas depresivos pueden afectar el estado de salud en personas que viven con el VIH (PLWH, por sus siglas en inglés), incluyendo la adherencia al tratamiento y el pronóstico de la enfermedad. Las intervenciones de autocuidado enfocadas a los síntomas depresivos han sido eficaces para prevenir estas secuelas negativas de los síntomas depresivos. Los procesos de autogestión incluyen habilidades de aprendizaje relacionadas con enfocarse a vivir con la enfermedad necesidades, acceder a recursos para manejar la enfermedad y afrontar a la enfermedad. Se realizó una revisión sistemática de la literatura para evaluar y sintetizar la evidencia actual de las intervenciones de autocuidado dirigidas a los síntomas depresivos en personas que viven con el VIH. Siguiendo las directrices PRISMA, se realizó una búsqueda electrónica en 4 bases de datos. Se incluyeron estudios originales escritos en inglés que utilizaron un diseño de ensayo controlado aleatorio para evaluar el efecto de la intervención de autocuidado sobre los síntomas depresivos. Se seleccionaron estudios que se publicaron el 19 de abril de 2022 o antes, obteniendo 13 artículos relevantes. El riesgo de sesgo se evaluó mediante la herramienta de evaluación de la calidad de los NIH para estudios de intervención controlados y se utilizó la síntesis narrativa para sintetizar los resultados. Se incluyeron de 40 a 755 participantes en los estudios. Los estudios utilizaron diversas medidas para evaluar los síntomas depresivos antes y después de la intervención, y los puntos temporales para evaluar los síntomas depresivos después de la intervención variaron. Mientras que 12 estudios mostraron una reducción significativa en los síntomas depresivos después de la intervención, solo 4 estudios que usaron entrenamiento individual o tecnología mostraron síntomas depresivos más bajos en los grupos de intervención en comparación con los grupos de control. Esta revisión se puede utilizar para informar la ampliación y difusión de estas intervenciones para mejorar los síntomas depresivos en las personas que viven con el VIH.


Assuntos
Infecções por HIV , Autogestão , Humanos , Depressão/prevenção & controle , Infecções por HIV/complicações , Infecções por HIV/terapia , Adaptação Psicológica , Aprendizagem , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Appl Opt ; 62(4): 886-893, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36821141

RESUMO

A single-lamp visible light positioning (VLP) system based on an optical camera is proposed and demonstrated. The system uses a circular light-emitting diode (LED) to transmit ID data, and a common smartphone camera for positioning. First, we propose a scheme to calculate the azimuth angle using a marked lamp bead, avoiding the use of a magnetometer, which can improve the accuracy of the azimuth angle. Second, we propose a new positioning method using a chord in the image plane, which passes through the midpoints of two chords parallel to the LED plane. The experimental results show that when the experimental area is 1.8m×3.6m, the three-dimensional (3D) average positioning errors are 8.0, 7.5, and 7.2 cm for the heights of 1.75, 1.45, and 1.2 m.

9.
AIDS Care ; 34(7): 926-935, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34612090

RESUMO

Little is known about how demographic, employment and meteorological factors impact physical activity. We conducted an analysis to explore these associations from participants (N = 447) from six cities in the United States and matched their activity data with abstracted local meteorological data from National Oceanic and Atmospheric Administration (NOAA) weather reports. Participants were purposively recruited in 3-month blocks, from December 2015 to October 2017, to reflect physical activity engagement across the seasons. We calculated total physical activity (minutes/week) based on 7-day physical activity recall. Mild correlations were observed between meteorological factors and correlated with lower physical activity. Participants were least active in autumn (Median = 220 min/week) and most active in spring (Median = 375 min/week). In addition to level of education and total hours of work, maximum temperature, relative humidity, heating degree day, precipitation and sunset time together explained 17.6% of variance in total physical activity. Programs assisting in employment for PLHIV and those that promote indoor physical activity during more strenuous seasons are needed. Additional research to better understand the selection, preferences, and impact of indoor environments on physical activity is warranted.


Assuntos
Infecções por HIV , Cidades , Exercício Físico , Infecções por HIV/epidemiologia , Humanos , Estações do Ano , Tempo (Meteorologia)
10.
Health Educ Res ; 36(1): 9-40, 2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33331898

RESUMO

The objective of this review was to investigate process of pictograph development and the effectiveness of pictographs in patient education. We conducted searches in Medline/PubMed, CINAHL with full text, PsycInfo, ERIC and Cochrane Library with keywords: (pictograph or pictorial) AND (patient education) NOT (children or adolescent or youth or child or teenagers). After excluding manuscripts that did not meet inclusion criteria, 56 articles were included between the time of the last review on this topic (January 2008) and May 2019. There are 17 descriptive studies, 27 randomized control trial studies, 9 quasi-experimental studies and 2 unique literatures in the systematic review. Major goals of the studies are pictograph development or validation. The majority of manuscripts (n = 48) supported the approach. However, six studies did not find significant differences in the outcome. Differences in patient population, pictograph designs and author-developed outcome measurements made it difficult to compare the findings. There is a lack of evidence on validating information outcome measurements. This review demonstrated that implementing pictographs into patient education is a promising approach for better information understanding and health management. Pictographic interventions need to be carefully developed and validated with both the targeted patient population and the clinical experts.


Assuntos
Família , Educação de Pacientes como Assunto , Adolescente , Criança , Compreensão , Humanos
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