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1.
Patterns (N Y) ; 5(7): 100987, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39081570

RESUMO

Structural neuroimaging studies have identified a combination of shared and disorder-specific patterns of gray matter (GM) deficits across psychiatric disorders. Pooling large data allows for examination of a possible common neuroanatomical basis that may identify a certain vulnerability for mental illness. Large-scale collaborative research is already facilitated by data repositories, institutionally supported databases, and data archives. However, these data-sharing methodologies can suffer from significant barriers. Federated approaches augment these approaches by enabling access or more sophisticated, shareable and scaled-up analyses of large-scale data. We examined GM alterations using Collaborative Informatics and Neuroimaging Suite Toolkit for Anonymous Computation, an open-source, decentralized analysis application. Through federated analysis of eight sites, we identified significant overlap in the GM patterns (n = 4,102) of individuals with schizophrenia, major depressive disorder, and autism spectrum disorder. These results show cortical and subcortical regions that may indicate a shared vulnerability to psychiatric disorders.

2.
Front Neuroinform ; 17: 1207721, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37404336

RESUMO

Collaborative neuroimaging research is often hindered by technological, policy, administrative, and methodological barriers, despite the abundance of available data. COINSTAC (The Collaborative Informatics and Neuroimaging Suite Toolkit for Anonymous Computation) is a platform that successfully tackles these challenges through federated analysis, allowing researchers to analyze datasets without publicly sharing their data. This paper presents a significant enhancement to the COINSTAC platform: COINSTAC Vaults (CVs). CVs are designed to further reduce barriers by hosting standardized, persistent, and highly-available datasets, while seamlessly integrating with COINSTAC's federated analysis capabilities. CVs offer a user-friendly interface for self-service analysis, streamlining collaboration, and eliminating the need for manual coordination with data owners. Importantly, CVs can also be used in conjunction with open data as well, by simply creating a CV hosting the open data one would like to include in the analysis, thus filling an important gap in the data sharing ecosystem. We demonstrate the impact of CVs through several functional and structural neuroimaging studies utilizing federated analysis showcasing their potential to improve the reproducibility of research and increase sample sizes in neuroimaging studies.

3.
bioRxiv ; 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37214791

RESUMO

Collaborative neuroimaging research is often hindered by technological, policy, administrative, and methodological barriers, despite the abundance of available data. COINSTAC is a platform that successfully tackles these challenges through federated analysis, allowing researchers to analyze datasets without publicly sharing their data. This paper presents a significant enhancement to the COINSTAC platform: COINSTAC Vaults (CVs). CVs are designed to further reduce barriers by hosting standardized, persistent, and highly-available datasets, while seamlessly integrating with COINSTAC's federated analysis capabilities. CVs offer a user-friendly interface for self-service analysis, streamlining collaboration and eliminating the need for manual coordination with data owners. Importantly, CVs can also be used in conjunction with open data as well, by simply creating a CV hosting the open data one would like to include in the analysis, thus filling an important gap in the data sharing ecosystem. We demonstrate the impact of CVs through several functional and structural neuroimaging studies utilizing federated analysis showcasing their potential to improve the reproducibility of research and increase sample sizes in neuroimaging studies.

4.
Neuroinformatics ; 21(2): 287-301, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36434478

RESUMO

With the growth of decentralized/federated analysis approaches in neuroimaging, the opportunities to study brain disorders using data from multiple sites has grown multi-fold. One such initiative is the Neuromark, a fully automated spatially constrained independent component analysis (ICA) that is used to link brain network abnormalities among different datasets, studies, and disorders while leveraging subject-specific networks. In this study, we implement the neuromark pipeline in COINSTAC, an open-source neuroimaging framework for collaborative/decentralized analysis. Decentralized exploratory analysis of nearly 2000 resting-state functional magnetic resonance imaging datasets collected at different sites across two cohorts and co-located in different countries was performed to study the resting brain functional network connectivity changes in adolescents who smoke and consume alcohol. Results showed hypoconnectivity across the majority of networks including sensory, default mode, and subcortical domains, more for alcohol than smoking, and decreased low frequency power. These findings suggest that global reduced synchronization is associated with both tobacco and alcohol use. This proof-of-concept work demonstrates the utility and incentives associated with large-scale decentralized collaborations spanning multiple sites.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Humanos , Adolescente , Vias Neurais/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Consumo de Bebidas Alcoólicas , Etanol , Fumar , Mapeamento Encefálico
5.
Neuroinformatics ; 20(2): 377-390, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34807353

RESUMO

The field of neuroimaging has embraced sharing data to collaboratively advance our understanding of the brain. However, data sharing, especially across sites with large amounts of protected health information (PHI), can be cumbersome and time intensive. Recently, there has been a greater push towards collaborative frameworks that enable large-scale federated analysis of neuroimaging data without the data having to leave its original location. However, there still remains a need for a standardized federated approach that not only allows for data sharing adhering to the FAIR (Findability, Accessibility, Interoperability, Reusability) data principles, but also streamlines analyses and communication while maintaining subject privacy. In this paper, we review a non-exhaustive list of neuroimaging analytic tools and frameworks currently in use. We then provide an update on our federated neuroimaging analysis software system, the Collaborative Informatics and Neuroimaging Suite Toolkit for Anonymous Computation (COINSTAC). In the end, we share insights on future research directions for federated analysis of neuroimaging data.


Assuntos
Disseminação de Informação , Neuroimagem , Disseminação de Informação/métodos , Software
6.
Neuroinformatics ; 19(4): 553-566, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33462781

RESUMO

There has been an upward trend in developing frameworks that enable neuroimaging researchers to address challenging questions by leveraging data across multiple sites all over the world. One such open-source framework is the Collaborative Informatics and Neuroimaging Suite Toolkit for Anonymous Computation (COINSTAC) that works on Windows, macOS, and Linux operating systems and leverages containerized analysis pipelines to analyze neuroimaging data stored locally across multiple physical locations without the need for pooling the data at any point during the analysis. In this paper, the COINSTAC team partnered with a data collection consortium to implement the first-ever decentralized voxelwise analysis of brain imaging data performed outside the COINSTAC development group. Decentralized voxel-based morphometry analysis of over 2000 structural magnetic resonance imaging data sets collected at 14 different sites across two cohorts and co-located in different countries was performed to study the structural changes in brain gray matter which linked to age, body mass index (BMI), and smoking. Results produced by the decentralized analysis were consistent with and extended previous findings in the literature. In particular, a widespread cortical gray matter reduction (resembling a 'default mode network' pattern) and hippocampal increase with age, bilateral increases in the hypothalamus and basal ganglia with BMI, and cingulate and thalamic decreases with smoking. This work provides a critical real-world test of the COINSTAC framework in a "Large-N" study. It showcases the potential benefits of performing multivoxel and multivariate analyses of large-scale neuroimaging data located at multiple sites.


Assuntos
Fatores Etários , Índice de Massa Corporal , Substância Cinzenta , Neuroimagem , Fumar , Adolescente , Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética
7.
Theor Biol Med Model ; 16(1): 21, 2019 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-31829209

RESUMO

BACKGROUND: Glucose tolerance testing is a tool used to estimate glucose effectiveness and insulin sensitivity in diabetic patients. The importance of such tests has prompted the development and utilisation of mathematical models that describe glucose kinetics as a function of insulin activity. The hormone glucagon, also plays a fundamental role in systemic plasma glucose regulation and is secreted reciprocally to insulin, stimulating catabolic glucose utilisation. However, regulation of glucagon secretion by α-cells is impaired in type-1 and type-2 diabetes through pancreatic islet dysfunction. Despite this, inclusion of glucagon activity when modelling the glucose kinetics during glucose tolerance testing is often overlooked. This study presents two mathematical models of a glucose tolerance test that incorporate glucose-insulin-glucagon dynamics. The first model describes a non-linear relationship between glucagon and glucose, whereas the second model assumes a linear relationship. RESULTS: Both models are validated against insulin-modified and glucose infusion intravenous glucose tolerance test (IVGTT) data, as well as insulin infusion data, and are capable of estimating patient glucose effectiveness (sG) and insulin sensitivity (sI). Inclusion of glucagon dynamics proves to provide a more detailed representation of the metabolic portrait, enabling estimation of two new diagnostic parameters: glucagon effectiveness (sE) and glucagon sensitivity (δ). CONCLUSIONS: The models are used to investigate how different degrees of pax'tient glucagon sensitivity and effectiveness affect the concentration of blood glucose and plasma glucagon during IVGTT and insulin infusion tests, providing a platform from which the role of glucagon dynamics during a glucose tolerance test may be investigated and predicted.


Assuntos
Glucagon/metabolismo , Teste de Tolerância a Glucose/métodos , Modelos Biológicos , Glicemia/metabolismo , Simulação por Computador , Humanos , Hipoglicemia/sangue , Resistência à Insulina , Modelos Lineares , Reprodutibilidade dos Testes
8.
Sci Rep ; 9(1): 6333, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-31004119

RESUMO

Redox cycling is an understated mechanism of toxicity associated with a plethora of xenobiotics, responsible for preventing the effective treatment of serious conditions such as malaria and cardiomyopathy. Quinone compounds are notorious redox cyclers, present in drugs such as doxorubicin, which is used to treat a host of human cancers. However, the therapeutic index of doxorubicin is undermined by dose-dependent cardiotoxicity, which may be a function of futile redox cycling. In this study, a doxorubicin-specific in silico quinone redox metabolism model is described. Doxorubicin-GSH adduct formation kinetics are thermodynamically estimated from its reduction potential, while the remainder of the model is parameterised using oxygen consumption rate data, indicative of hydroquinone auto-oxidation. The model is then combined with a comprehensive glutathione metabolism model, facilitating the simulation of quinone redox cycling, and adduct-induced GSH depletion. Simulations suggest that glutathione pools are most sensitive to exposure duration at pharmacologically and supra-pharmacologically relevant doxorubicin concentrations. The model provides an alternative method of investigating and quantifying redox cycling induced oxidative stress, circumventing the experimental difficulties of measuring and tracking radical species. This in silico framework provides a platform from which GSH depletion can be explored as a function of a compound's physicochemical properties.


Assuntos
Benzoquinonas/metabolismo , Glutationa/metabolismo , Modelos Biológicos , Neoplasias/metabolismo , Animais , Humanos , Neoplasias/tratamento farmacológico , Oxirredução
9.
PLoS One ; 13(11): e0207803, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30496306

RESUMO

Cancer cells depend on glucose metabolism via glycolysis as a primary energy source, despite the presence of oxygen and fully functioning mitochondria, in order to promote growth, proliferation and longevity. Glycolysis relies upon NAD+ to accept electrons in the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) reaction, linking the redox state of the cytosolic NAD+ pool to glycolytic rate. The free cytosolic NAD+/NADH ratio is involved in over 700 oxidoreductive enzymatic reactions and as such, the NAD+/NADH ratio is regarded as a metabolic readout of overall cellular redox state. Many experimental techniques that monitor or measure total NAD+ and NADH are unable to distinguish between protein-bound and unbound forms. Yet total NAD+/NADH measurements yield little information, since it is the free forms of NAD+ and NADH that determine the kinetic and thermodynamic influence of redox potential on glycolytic rate. Indirect estimations of free NAD+/NADH are based on the lactate/pyruvate (L/P) ratio at chemical equilibrium, but these measurements are often undermined by high lability. To elucidate the sensitivity of the free NAD+/NADH ratio to changes in extracellular substrate, an in silico model of hepatocarcinoma glycolysis was constructed and validated against in vitro data. Model simulations reveal that over experimentally relevant concentrations, changes in extracellular glucose and lactate concentration during routine cancer cell culture can lead to significant deviations in the NAD+/NADH ratio. Based on the principles of chemical equilibrium, the model provides a platform from which experimentally challenging situations may be examined, suggesting that extracellular substrates play an important role in cellular redox and bioenergetic homeostasis.


Assuntos
Citosol/metabolismo , Espaço Extracelular/metabolismo , Modelos Biológicos , NAD/metabolismo , Trifosfato de Adenosina/metabolismo , Citoplasma/metabolismo , Metabolismo Energético , Glicólise , Ácido Láctico/metabolismo , Análise do Fluxo Metabólico
10.
J Environ Qual ; 47(4): 884-892, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30025054

RESUMO

The nature and management of agricultural soils can influence the forms of legacy P present in affected sediments; however, few studies have specifically characterized P in sediments affected by polder agriculture. In this study, the speciation of P as it flows from the muck soils of the Holland Marsh to the sediments of the West Holland River and Lake Simcoe, Ontario, Canada, was investigated. The distribution of P fractions and the characterization of organic P were analyzed by the sequential fractionation method and solution P nuclear magnetic resonance spectroscopy, respectively. Organic P was the predominant P form (∼58% of total P) in muck soils, whereas the redox-sensitive P fraction was predominant in surface stream sediments rich in organic matter (∼41-48% of total P), despite these sediments exhibiting near-neutral pH and high concentrations of both Ca and P. The proportion of relatively recalcitrant organic P forms was much greater in the muck soils than that exhibited by both stream and lake sediments. The decreasing proportion of recalcitrant organic P forms in sediments downstream from the Holland Marsh indicated the potential for faster organic P cycling. Our findings support the notion that diesters and pyrophosphate should be monitored, in addition to loosely bound inorganic P, due to their potential impact on water quality. The unique environment of the streams and lake area is considered to be particularly vulnerable to excessive fertilizer P use in adjacent croplands.


Assuntos
Agricultura , Fósforo/química , Resíduos Sólidos , Poluentes Químicos da Água/química , Canadá , China , Monitoramento Ambiental , Sedimentos Geológicos , Lagos , Fósforo/análise , Solo , Poluentes Químicos da Água/análise
12.
F1000Res ; 6: 1512, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29123643

RESUMO

In the era of Big Data, sharing neuroimaging data across multiple sites has become increasingly important. However, researchers who want to engage in centralized, large-scale data sharing and analysis must often contend with problems such as high database cost, long data transfer time, extensive manual effort, and privacy issues for sensitive data. To remove these barriers to enable easier data sharing and analysis, we introduced a new, decentralized, privacy-enabled infrastructure model for brain imaging data called COINSTAC in 2016. We have continued development of COINSTAC since this model was first introduced. One of the challenges with such a model is adapting the required algorithms to function within a decentralized framework. In this paper, we report on how we are solving this problem, along with our progress on several fronts, including additional decentralized algorithms implementation, user interface enhancement, decentralized regression statistic calculation, and complete pipeline specifications.

14.
Neuroimage ; 124(Pt B): 1084-1088, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26019122

RESUMO

Neuroimaging data collection is inherently expensive. Maximizing the return on investment in neuroimaging studies requires that neuroimaging data be re-used whenever possible. In an effort to further scientific knowledge, the COINS Data Exchange (DX) (http://coins.mrn.org/dx) aims to make data sharing seamless and commonplace. DX takes a three-pronged approach towards improving the overall state of data sharing within the neuroscience community. The first prong is compiling data into one location that has been collected from all over the world in many different formats. The second prong is curating the data so that it can be stored in one consistent format and so that data QA/QC measures can be assured. The third prong is disseminating the data so that it is easy to consume and straightforward to interpret. This paper explains the concepts behind each prong and describes some challenges and successes that the Data Exchange has experienced.


Assuntos
Disseminação de Informação/métodos , Neuroimagem/estatística & dados numéricos , Acesso à Informação , Humanos , Informática , Internet , Neurociências/tendências
15.
Front Neuroinform ; 8: 71, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25206330

RESUMO

Neuroscientists increasingly need to work with big data in order to derive meaningful results in their field. Collecting, organizing and analyzing this data can be a major hurdle on the road to scientific discovery. This hurdle can be lowered using the same technologies that are currently revolutionizing the way that cultural and social media sites represent and share information with their users. Web application technologies and standards such as RESTful webservices, HTML5 and high-performance in-browser JavaScript engines are being utilized to vastly improve the way that the world accesses and shares information. The neuroscience community can also benefit tremendously from these technologies. We present here a web application that allows users to explore and request the complex datasets that need to be shared among the neuroimaging community. The COINS (Collaborative Informatics and Neuroimaging Suite) Data Exchange uses web application technologies to facilitate data sharing in three phases: Exploration, Request/Communication, and Download. This paper will focus on the first phase, and how intuitive exploration of large and complex datasets is achieved using a framework that centers around asynchronous client-server communication (AJAX) and also exposes a powerful API that can be utilized by other applications to explore available data. First opened to the neuroscience community in August 2012, the Data Exchange has already provided researchers with over 2500 GB of data.

16.
Front Neuroinform ; 8: 60, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24926252

RESUMO

Accurate data collection at the ground level is vital to the integrity of neuroimaging research. Similarly important is the ability to connect and curate data in order to make it meaningful and sharable with other investigators. Collecting data, especially with several different modalities, can be time consuming and expensive. These issues have driven the development of automated collection of neuroimaging and clinical assessment data within COINS (Collaborative Informatics and Neuroimaging Suite). COINS is an end-to-end data management system. It provides a comprehensive platform for data collection, management, secure storage, and flexible data retrieval (Bockholt et al., 2010; Scott et al., 2011). It was initially developed for the investigators at the Mind Research Network (MRN), but is now available to neuroimaging institutions worldwide. Self Assessment (SA) is an application embedded in the Assessment Manager (ASMT) tool in COINS. It is an innovative tool that allows participants to fill out assessments via the web-based Participant Portal. It eliminates the need for paper collection and data entry by allowing participants to submit their assessments directly to COINS. Instruments (surveys) are created through ASMT and include many unique question types and associated SA features that can be implemented to help the flow of assessment administration. SA provides an instrument queuing system with an easy-to-use drag and drop interface for research staff to set up participants' queues. After a queue has been created for the participant, they can access the Participant Portal via the internet to fill out their assessments. This allows them the flexibility to participate from home, a library, on site, etc. The collected data is stored in a PostgresSQL database at MRN. This data is only accessible by users that have explicit permission to access the data through their COINS user accounts and access to MRN network. This allows for high volume data collection and with minimal user access to PHI (protected health information). An added benefit to using COINS is the ability to collect, store and share imaging data and assessment data with no interaction with outside tools or programs. All study data collected (imaging and assessment) is stored and exported with a participant's unique subject identifier so there is no need to keep extra spreadsheets or databases to link and keep track of the data. Data is easily exported from COINS via the Query Builder and study portal tools, which allow fine grained selection of data to be exported into comma separated value file format for easy import into statistical programs. There is a great need for data collection tools that limit human intervention and error while at the same time providing users with intuitive design. COINS aims to be a leader in database solutions for research studies collecting data from several different modalities.

19.
ACS Nano ; 5(8): 6651-60, 2011 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-21749154

RESUMO

Xanthine molecule is an intermediate in nucleic acid degradation from the deamination of guanine and is also a compound present in the ancient solar system that is found in high concentrations in extraterrestrial meteorites. The self-assembly of xanthine molecules on inorganic surfaces is therefore of interest for the study of biochemical processes, and it may also be relevant to the fundamental understanding of prebiotic biosynthesis. Using a combination of high-resolution scanning tunneling microscopy (STM) and density functional theory (DFT) calculations, two new homochiral xanthine structures have been found on Au(111) under ultrahigh vacuum conditions. Xanthine molecules are found to be self-assembled into two extended homochiral networks tiled by two types of di-pentamer units and stabilized by intermolecular double hydrogen bonding. Our findings indicate that the deamination of guanine into xanthine leads to a very different base pairing potential and the chemical properties of the base which may be of relevance to the function of the cell and potential development of human diseases. Moreover, the adsorption of xanthine molecules on inorganic surfaces leading to homochiral assemblies may be of interest for the fundamental understanding of the emerged chirality at early stages of life.

20.
Aust N Z J Obstet Gynaecol ; 51(2): 147-50, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21466517

RESUMO

AIM: To determine the body mass index (BMI) and the body composition of fathers-to-be and to compare the findings with those of mothers-to-be during early pregnancy. METHODS: This was a descriptive and comparative study based at a large university teaching hospital. We enrolled men whose partner booked for antenatal care in the first trimester of pregnancy during July 2009. The height and weight of both parents-to-be were measured digitally, and BMI was calculated. The body compositions of the couple were analysed using bioelectrical impedance. RESULTS: Of 167 fathers-to-be, 14% were obese (BMI > 29.9 kg/m2 ) compared with 16% of mothers-to-be (NS). However, 50% were overweight (BMI 25.0-29.9 kg/m(2) ) compared with 26% of mothers-to-be (P < 0.001). This may be explained, in part, because the men were on average two years older than the women, and in the men, BMI increased with age. The men had a lower overall fat percentage (P < 0.001), but their visceral fat was higher than in the women (P < 0.001). CONCLUSION: Our findings show a high level of obesity in fathers-to-be, which has implications not only for the men themselves but also their families. We suggest that public health interventions directed at obesity during pregnancy should include both parents-to-be.


Assuntos
Índice de Massa Corporal , Pai , Mães , Obesidade/diagnóstico , Sobrepeso/diagnóstico , Primeiro Trimestre da Gravidez , Adiposidade , Adulto , Composição Corporal , Estudos de Coortes , Feminino , Humanos , Masculino , Obesidade/etiologia , Sobrepeso/etiologia , Gravidez
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