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1.
Nat Biomed Eng ; 8(3): 233-247, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37474612

RESUMO

Protein glycosylation, a complex and heterogeneous post-translational modification that is frequently dysregulated in disease, has been difficult to analyse at scale. Here we report a data-independent acquisition technique for the large-scale mass-spectrometric quantification of glycopeptides in plasma samples. The technique, which we named 'OxoScan-MS', identifies oxonium ions as glycopeptide fragments and exploits a sliding-quadrupole dimension to generate comprehensive and untargeted oxonium ion maps of precursor masses assigned to fragment ions from non-enriched plasma samples. By applying OxoScan-MS to quantify 1,002 glycopeptide features in the plasma glycoproteomes from patients with COVID-19 and healthy controls, we found that severe COVID-19 induces differential glycosylation in IgA, haptoglobin, transferrin and other disease-relevant plasma glycoproteins. OxoScan-MS may allow for the quantitative mapping of glycoproteomes at the scale of hundreds to thousands of samples.


Assuntos
COVID-19 , Glicopeptídeos , Humanos , Espectrometria de Massas , Glicosilação , Glicopeptídeos/análise , Glicopeptídeos/química , Glicopeptídeos/metabolismo , Íons
2.
HardwareX ; 15: e00443, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37795340

RESUMO

Behaviour is the ultimate output of neural circuit computations, and therefore its analysis is a cornerstone of neuroscience research. However, every animal and experimental paradigm requires different illumination conditions to capture and, in some cases, manipulate specific behavioural features. This means that researchers often develop, from scratch, their own solutions and experimental set-ups. Here, we present OptoPi, an open source, affordable (∼ £600), behavioural arena with accompanying multi-animal tracking software. The system features highly customisable and reproducible visible and infrared illumination and allows for optogenetic stimulation. OptoPi acquires images using a Raspberry Pi camera, features motorised LED-based illumination, Arduino control, as well as irradiance monitoring to fine-tune illumination conditions with real time feedback. Our open-source software (BioImageProcessing) can be used to simultaneously track multiple unmarked animals both in on-line and off-line modes. We demonstrate the functionality of OptoPi by recording and tracking under different illumination conditions the spontaneous behaviour of larval zebrafish as well as adult Drosophila flies and their first instar larvae, an experimental animal that due to its small size and transparency has classically been hard to track. Further, we showcase OptoPi's optogenetic capabilities through a series of experiments using transgenic Drosophila larvae.

3.
IEEE Trans Med Imaging ; 42(12): 3956-3971, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37768797

RESUMO

In this paper, we present the results of the MitoEM challenge on mitochondria 3D instance segmentation from electron microscopy images, organized in conjunction with the IEEE-ISBI 2021 conference. Our benchmark dataset consists of two large-scale 3D volumes, one from human and one from rat cortex tissue, which are 1,986 times larger than previously used datasets. At the time of paper submission, 257 participants had registered for the challenge, 14 teams had submitted their results, and six teams participated in the challenge workshop. Here, we present eight top-performing approaches from the challenge participants, along with our own baseline strategies. Posterior to the challenge, annotation errors in the ground truth were corrected without altering the final ranking. Additionally, we present a retrospective evaluation of the scoring system which revealed that: 1) challenge metric was permissive with the false positive predictions; and 2) size-based grouping of instances did not correctly categorize mitochondria of interest. Thus, we propose a new scoring system that better reflects the correctness of the segmentation results. Although several of the top methods are compared favorably to our own baselines, substantial errors remain unsolved for mitochondria with challenging morphologies. Thus, the challenge remains open for submission and automatic evaluation, with all volumes available for download.


Assuntos
Córtex Cerebral , Mitocôndrias , Humanos , Ratos , Animais , Estudos Retrospectivos , Microscopia Eletrônica , Processamento de Imagem Assistida por Computador/métodos
4.
Traffic ; 22(7): 240-253, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33914396

RESUMO

Advancements in volume electron microscopy mean it is now possible to generate thousands of serial images at nanometre resolution overnight, yet the gold standard approach for data analysis remains manual segmentation by an expert microscopist, resulting in a critical research bottleneck. Although some machine learning approaches exist in this domain, we remain far from realizing the aspiration of a highly accurate, yet generic, automated analysis approach, with a major obstacle being lack of sufficient high-quality ground-truth data. To address this, we developed a novel citizen science project, Etch a Cell, to enable volunteers to manually segment the nuclear envelope (NE) of HeLa cells imaged with serial blockface scanning electron microscopy. We present our approach for aggregating multiple volunteer annotations to generate a high-quality consensus segmentation and demonstrate that data produced exclusively by volunteers can be used to train a highly accurate machine learning algorithm for automatic segmentation of the NE, which we share here, in addition to our archived benchmark data.


Assuntos
Aprendizado Profundo , Células HeLa , Humanos , Microscopia Eletrônica , Membrana Nuclear , Voluntários
5.
Telemed J E Health ; 24(12): 940-957, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30129884

RESUMO

Objective: To investigate the potential of an integrated care system that acquires vital clinical signs and habits data to support independent living for elderly people with chronic disease. Materials and Methods: We developed an IEEE 11073 standards-based telemonitoring platform for monitoring vital signs and activity data of elderly living alone in their home. The platform has important features for monitoring the elderly: unobtrusive, simple, elderly-friendly, plug and play interoperable, and self-integration of sensors. Thirty-six (36) patients in a primary care practice in the United Kingdom (mean [standard deviation] age, 82 [10] years) with congestive heart failure (CHF) or chronic obstructive pulmonary disease (COPD) were provided with clinical sensors to measure the vital signs for their disease (blood pressure [BP] and weight for CHF, and oxygen saturation for COPD) and one passive infrared (PIR) motion sensor and/or a chair/bed sensor were installed in a patient's home to obtain their activity data. The patients were asked to take one measurement each day of their vital signs in the morning before breakfast. All data were automatically transmitted wirelessly to the remote server and displayed on a clinical portal for clinicians to monitor each patient. An alert algorithm detected outliers in the data and indicated alerts on the portal. Patient data have been analyzed retrospectively following hospital admission, emergency room visit or death, to determine whether the data could predict the event. Results: Data of patients who were monitored for a long period and had interventions were analyzed to identify useful parameters and develop algorithms to define alert rules. Twenty of the 36 participants had a clinical referral during the time of monitoring; 16 of them received some type of intervention. The most common reason for intervention was due to low oxygen levels for patients with COPD and high BP levels for CHF. Activity data were found to contain information on the well-being of patients, in particular for those with COPD. During exacerbation the activity level from PIR sensors increased slightly, and there was a decrease in bed occupancy. One subject with CHF who felt unwell spent most of the day in the bedroom. Conclusions: Our results suggest that integrated care monitoring technologies have a potential for providing improved care and can have positive impact on well-being of the elderly by enabling timely intervention. Long-term BP and pulse oximetry data could indicate exacerbation and lead to effective intervention; physical activity data provided important information on the well-being of patients. However, there remains a need for better understanding of long-term variations in vital signs and activity data to establish intervention protocols for improved disease management.


Assuntos
Idoso Fragilizado , Insuficiência Cardíaca/terapia , Monitorização Ambulatorial/métodos , Doença Pulmonar Obstrutiva Crônica/terapia , Telemetria/métodos , Idoso , Pressão Sanguínea , Peso Corporal , Doença Crônica , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Oximetria , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Estudos Retrospectivos
6.
Int J Technol Assess Health Care ; 34(2): 163-171, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29633673

RESUMO

OBJECTIVES: Value assessment frameworks have gained prominence recently in the context of U.S. healthcare. Such frameworks set out a series of factors that are considered in funding decisions. The UK's National Institute of Health and Care Excellence (NICE) is an established health technology assessment (HTA) agency. We present a novel application of text analysis that characterizes NICE's Technology Appraisals in the context of the newer assessment frameworks and present the results in a visual way. METHODS: A total of 243 documents of NICE's medicines guidance from 2007 to 2016 were analyzed. Text analysis was used to identify a hierarchical set of decision factors considered in the assessments. The frequency of decision factors stated in the documents was determined and their association with terms related to uncertainty. The results were incorporated into visual representations of hierarchical factors. RESULTS: We identified 125 decision factors, and hierarchically grouped these into eight domains: Clinical Effectiveness, Cost Effectiveness, Condition, Current Practice, Clinical Need, New Treatment, Studies, and Other Factors. Textual analysis showed all domains appeared consistently in the guidance documents. Many factors were commonly associated with terms relating to uncertainty. A series of visual representations was created. CONCLUSIONS: This study reveals the complexity and consistency of NICE's decision-making processes and demonstrates that cost effectiveness is not the only decision-criteria. The study highlights the importance of processes and methodology that can take both quantitative and qualitative information into account. Visualizations can help effectively communicate this complex information during the decision-making process and subsequently to stakeholders.


Assuntos
Tomada de Decisões , Medicina Estatal/organização & administração , Avaliação da Tecnologia Biomédica/organização & administração , Análise Custo-Benefício , Humanos , Anos de Vida Ajustados por Qualidade de Vida , Incerteza , Reino Unido
7.
IEEE Trans Biomed Eng ; 65(5): 1014-1025, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28796600

RESUMO

This paper describes the implementation of an end-to-end remote monitoring platform based on the IEEE 11073 standards for personal health devices (PHD). It provides an overview of the concepts and approaches and describes how the standard has been optimized for small devices with limited resources of processor, memory, and power that use short-range wireless technology. It explains aspects of IEEE 11073, including the domain information model, state model, and nomenclature, and how these support its plug-and-play architecture. It shows how these aspects underpin a much larger ecosystem of interoperable devices and systems that include IHE PCD-01, HL7, and BlueTooth LE medical devices, and the relationship to the Continua Guidelines, advocating the adoption of data standards and nomenclature to support semantic interoperability between health and ambient assisted living in future platforms. The paper further describes the adaptions that have been made in order to implement the standard on the ZigBee Health Care Profile and the experiences of implementing an end-to-end platform that has been deployed to frail elderly patients with chronic disease(s) and patients with diabetes.


Assuntos
Monitorização Ambulatorial/métodos , Telemedicina/métodos , Idoso , Doença Crônica , Redes de Comunicação de Computadores , Serviços de Assistência Domiciliar , Humanos , Tecnologia sem Fio
8.
BMC Med Inform Decis Mak ; 14: 102, 2014 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-25433372

RESUMO

BACKGROUND: Changes in daily habits can provide important information regarding the overall health status of an individual. This research aimed to determine how meaningful information may be extracted from limited sensor data and transformed to provide clear visualization for the clinicians who must use and interact with the data and make judgments on the condition of patients. We ascertained that a number of insightful features related to habits and physical condition could be determined from usage and motion sensor data. METHODS: Our approach to the design of the visualization follows User Centered Design, specifically, defining requirements, designing corresponding visualizations and finally evaluating results. This cycle was iterated three times. RESULTS: The User Centered Design method was successfully employed to converge to a design that met the main objective of this study. The resulting visualizations of relevant features that were extracted from the sensor data were considered highly effective and intuitive to the clinicians and were considered suitable for monitoring the behavior patterns of patients. CONCLUSIONS: We observed important differences in the approach and attitude of the researchers and clinicians. Whereas the researchers would prefer to have as many features and information as possible in each visualization, the clinicians would prefer clarity and simplicity, often each visualization having only a single feature, with several visualizations per page. In addition, concepts considered intuitive to the researchers were not always to the clinicians.


Assuntos
Sistemas de Apoio a Decisões Clínicas/instrumentação , Idoso Fragilizado , Hábitos , Monitorização Ambulatorial/instrumentação , Reconhecimento Visual de Modelos , Telemedicina/instrumentação , Idoso , Atitude do Pessoal de Saúde , Desenho de Equipamento , Estudos de Avaliação como Assunto , Feminino , Humanos , Entrevistas como Assunto , Masculino , Monitorização Ambulatorial/métodos , Movimento (Física) , Pesquisa Qualitativa , Telemedicina/métodos
9.
J Chromatogr A ; 1218(36): 6144-7, 2011 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-21227439

RESUMO

Selected test results have been taken from various publications and resolution and stage efficiency measured using an established model. All experiments used the same sample and, where possible, the same sample loading. The results show that stage mixing efficiencies have increased from 1.1% in 1998 to greater than 25% in the latest scaled-up version of a Toroidal coil chromatography (TCC) instrument working at 240 g.


Assuntos
Cromatografia/métodos , Muramidase/isolamento & purificação , Mioglobina/isolamento & purificação , Cromatografia/instrumentação
10.
J Chromatogr A ; 1218(36): 6009-14, 2011 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-21211802

RESUMO

Chromatography models, liquid-liquid models and specifically Counter-Current Chromatography (CCC) models are usually either iterative, or provide a final solution for peak elution. This paper describes providing a better model by finding a more elemental solution. A completely new model has been developed based on simulating probabilistic units. This model has been labelled ProMISE (probabilistic model for immiscible phase separations and extractions), and has been realised in the form of a computer application, interactively visualising the behaviour of the units in the CCC process. It does not use compartments or cells like in the Craig based models, nor is it based on diffusion theory. With this new model, all the CCC flow modes can be accurately predicted. The main advantage over the previously developed model, is that it does not require a somewhat arbitrary number of steps or theoretical plates, and instead uses an efficiency factor. Furthermore, since this model is not based on compartments or cells like the Craig model, and is therefore not limited to a compartment or cell nature, it allows for an even greater flexibility.


Assuntos
Fracionamento Químico/instrumentação , Distribuição Contracorrente/instrumentação , Fracionamento Químico/métodos , Distribuição Contracorrente/métodos , Modelos Estatísticos , Modelos Teóricos
11.
J Chromatogr A ; 1216(19): 4218-24, 2009 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-19070863

RESUMO

There is clearly a need for a model which is versatile enough to take into account the numerous operating modes and pump out procedures that can be used with counter-current chromatography (CCC). This paper will describe a universal model for counter-current chromatography based on counter-current distribution. The model is validated with real separations from the literature and against established CCC partition theory. This universal model is proven to give good results for isocratic flow modes, as well as for co-current CCC and dual flow CCC, and will likely also give good results for other modes such as intermittent CCC.


Assuntos
Distribuição Contracorrente/métodos , Modelos Teóricos , Algoritmos , Simulação por Computador , Reprodutibilidade dos Testes
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