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1.
Cell ; 185(15): 2632-2635, 2022 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-35868268

RESUMO

Ancient DNA (aDNA) techniques applied to human genomics have significantly advanced in the past decade, enabling large-scale aDNA research, sometimes independent of human remains. This commentary reviews the major milestones of aDNA techniques and explores future directions to expand the scope of aDNA research and insights into present-day human health.


Assuntos
DNA Antigo , Genoma Humano , História Antiga , Humanos
2.
Annu Rev Biochem ; 89: 159-187, 2020 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-32176523

RESUMO

This review focuses on imaging DNA and single RNA molecules in living cells to define eukaryotic functional organization and dynamic processes. The latest advances in technologies to visualize individual DNA loci and RNAs in real time are discussed. Single-molecule fluorescence microscopy provides the spatial and temporal resolution to reveal mechanisms regulating fundamental cell functions. Novel insights into the regulation of nuclear architecture, transcription, posttranscriptional RNA processing, and RNA localization provided by multicolor fluorescence microscopy are reviewed. A perspective on the future use of live imaging technologies and overcoming their current limitations is provided.


Assuntos
Núcleo Celular/ultraestrutura , Cromatina/ultraestrutura , DNA/ultraestrutura , Regulação da Expressão Gênica , RNA Mensageiro/ultraestrutura , Pequeno RNA não Traduzido/ultraestrutura , Animais , Núcleo Celular/genética , Núcleo Celular/metabolismo , Cromatina/metabolismo , DNA/genética , DNA/metabolismo , Replicação do DNA , Células Eucarióticas/metabolismo , Células Eucarióticas/ultraestrutura , Humanos , Microscopia de Fluorescência , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Pequeno RNA não Traduzido/genética , Pequeno RNA não Traduzido/metabolismo , Imagem Individual de Molécula/instrumentação , Imagem Individual de Molécula/métodos , Coloração e Rotulagem/métodos , Telômero/metabolismo , Telômero/ultraestrutura , Transcrição Gênica
3.
Annu Rev Biochem ; 88: 25-33, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-30986087

RESUMO

Over the past six decades, steadily increasing progress in the application of the principles and techniques of the physical sciences to the study of biological systems has led to remarkable insights into the molecular basis of life. Of particular significance has been the way in which the determination of the structures and dynamical properties of proteins and nucleic acids has so often led directly to a profound understanding of the nature and mechanism of their functional roles. The increasing number and power of experimental and theoretical techniques that can be applied successfully to living systems is now ushering in a new era of structural biology that is leading to fundamentally new information about the maintenance of health, the origins of disease, and the development of effective strategies for therapeutic intervention. This article provides a brief overview of some of the most powerful biophysical methods in use today, along with references that provide more detailed information about recent applications of each of them. In addition, this article acts as an introduction to four authoritative reviews in this volume. The first shows the ways that a multiplicity of biophysical methods can be combined with computational techniques to define the architectures of complex biological systems, such as those involving weak interactions within ensembles of molecular components. The second illustrates one aspect of this general approach by describing how recent advances in mass spectrometry, particularly in combination with other techniques, can generate fundamentally new insights into the properties of membrane proteins and their functional interactions with lipid molecules. The third reviewdemonstrates the increasing power of rapidly evolving diffraction techniques, employing the very short bursts of X-rays of extremely high intensity that are now accessible as a result of the construction of free-electron lasers, in particular to carry out time-resolved studies of biochemical reactions. The fourth describes in detail the application of such approaches to probe the mechanism of the light-induced changes associated with bacteriorhodopsin's ability to convert light energy into chemical energy.


Assuntos
Microscopia Crioeletrônica/métodos , Cristalografia por Raios X/métodos , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Biologia Molecular/métodos , Química Analítica/história , Microscopia Crioeletrônica/história , Microscopia Crioeletrônica/instrumentação , Cristalografia por Raios X/história , Cristalografia por Raios X/instrumentação , História do Século XX , História do Século XXI , Humanos , Lasers/história , Espectroscopia de Ressonância Magnética/história , Espectroscopia de Ressonância Magnética/instrumentação , Espectrometria de Massas/história , Espectrometria de Massas/instrumentação , Biologia Molecular/história , Biologia Molecular/instrumentação , Ácidos Nucleicos/química , Ácidos Nucleicos/ultraestrutura , Proteínas/química , Proteínas/ultraestrutura
4.
Annu Rev Neurosci ; 44: 27-48, 2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34236888

RESUMO

The common marmoset (Callithrix jacchus), a small New World primate, is receiving substantial attention in the neuroscience and biomedical science fields because its anatomical features, functional and behavioral characteristics, and reproductive features and its amenability to available genetic modification technologies make it an attractive experimental subject. In this review, I outline the progress of marmoset neuroscience research and summarize both the current status (opportunities and limitations) of and the future perspectives on the application of marmosets in neuroscience and disease modeling.


Assuntos
Callithrix , Neurociências , Animais , Neurobiologia , Reprodução
5.
EMBO J ; 43(14): 3009-3026, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38811852

RESUMO

The complement is a conserved cascade that plays a central role in the innate immune system. To maintain a delicate equilibrium preventing excessive complement activation, complement inhibitors are essential. One of the major fluid-phase complement inhibitors is C4b-binding protein (C4BP). Human C4BP is a macromolecular glycoprotein composed of two distinct subunits, C4BPα and C4BPß. These associate with vitamin K-dependent protein S (ProS) forming an ensemble of co-occurring higher-order structures. Here, we characterize these C4BP assemblies. We resolve and quantify isoforms of purified human serum C4BP using distinct single-particle detection techniques: charge detection mass spectrometry, and mass photometry accompanied by high-speed atomic force microscopy. Combining cross-linking mass spectrometry, glycoproteomics, and structural modeling, we report comprehensive glycoproteoform profiles and full-length structural models of the endogenous C4BP assemblies, expanding knowledge of this key complement inhibitor's structure and composition. Finally, we reveal that an increased C4BPα to C4BPß ratio coincides with elevated C-reactive protein levels in patient plasma samples. This observation highlights C4BP isoform variation and affirms a distinct role of co-occurring C4BP assemblies upon acute phase inflammation.


Assuntos
Proteína de Ligação ao Complemento C4b , Humanos , Proteína de Ligação ao Complemento C4b/metabolismo , Espectrometria de Massas , Isoformas de Proteínas/química , Isoformas de Proteínas/sangue , Modelos Moleculares , Proteína C-Reativa/metabolismo , Proteína C-Reativa/química , Microscopia de Força Atômica , Conformação Proteica
6.
Proc Natl Acad Sci U S A ; 121(10): e2314083121, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38427599

RESUMO

In a stack of atomically thin van der Waals layers, introducing interlayer twist creates a moiré superlattice whose period is a function of twist angle. Changes in that twist angle of even hundredths of a degree can dramatically transform the system's electronic properties. Setting a precise and uniform twist angle for a stack remains difficult; hence, determining that twist angle and mapping its spatial variation is very important. Techniques have emerged to do this by imaging the moiré, but most of these require sophisticated infrastructure, time-consuming sample preparation beyond stack synthesis, or both. In this work, we show that torsional force microscopy (TFM), a scanning probe technique sensitive to dynamic friction, can reveal surface and shallow subsurface structure of van der Waals stacks on multiple length scales: the moirés formed between bi-layers of graphene and between graphene and hexagonal boron nitride (hBN) and also the atomic crystal lattices of graphene and hBN. In TFM, torsional motion of an Atomic Force Microscope (AFM) cantilever is monitored as it is actively driven at a torsional resonance while a feedback loop maintains contact at a set force with the sample surface. TFM works at room temperature in air, with no need for an electrical bias between the tip and the sample, making it applicable to a wide array of samples. It should enable determination of precise structural information including twist angles and strain in moiré superlattices and crystallographic orientation of van der Waals flakes to support predictable moiré heterostructure fabrication.

7.
Circ Res ; 134(9): 1061-1082, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38662865

RESUMO

Wildfire smoke (WFS) is a mixture of respirable particulate matter, environmental gases, and other hazardous pollutants that originate from the unplanned burning of arid vegetation during wildfires. The increasing size and frequency of recent wildfires has escalated public and occupational health concerns regarding WFS inhalation, by either individuals living nearby and downstream an active fire or wildland firefighters and other workers that face unavoidable exposure because of their profession. In this review, we first synthesize current evidence from environmental, controlled, and interventional human exposure studies, to highlight positive associations between WFS inhalation and cardiovascular morbidity and mortality. Motivated by these findings, we discuss preventative measures and suggest interventions to mitigate the cardiovascular impact of wildfires. We then review animal and cell exposure studies to call attention on the pathophysiological processes that support the deterioration of cardiovascular tissues and organs in response to WFS inhalation. Acknowledging the challenges of integrating evidence across independent sources, we contextualize laboratory-scale exposure approaches according to the biological processes that they model and offer suggestions for ensuring relevance to the human condition. Noting that wildfires are significant contributors to ambient air pollution, we compare the biological responses triggered by WFS to those of other harmful pollutants. We also review evidence for how WFS inhalation may trigger mechanisms that have been proposed as mediators of adverse cardiovascular effects upon exposure to air pollution. We finally conclude by highlighting research areas that demand further consideration. Overall, we aspire for this work to serve as a catalyst for regulatory initiatives to mitigate the adverse cardiovascular effects of WFS inhalation in the community and alleviate the occupational risk in wildland firefighters.


Assuntos
Doenças Cardiovasculares , Fumaça , Incêndios Florestais , Humanos , Animais , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Fumaça/efeitos adversos , Exposição por Inalação/efeitos adversos , Poluentes Atmosféricos/efeitos adversos , Material Particulado/efeitos adversos , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/prevenção & controle , Exposição Ambiental/efeitos adversos
8.
Mol Cell Proteomics ; 23(3): 100731, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38331191

RESUMO

Proteomics data sharing has profound benefits at the individual level as well as at the community level. While data sharing has increased over the years, mostly due to journal and funding agency requirements, the reluctance of researchers with regard to data sharing is evident as many shares only the bare minimum dataset required to publish an article. In many cases, proper metadata is missing, essentially making the dataset useless. This behavior can be explained by a lack of incentives, insufficient awareness, or a lack of clarity surrounding ethical issues. Through adequate training at research institutes, researchers can realize the benefits associated with data sharing and can accelerate the norm of data sharing for the field of proteomics, as has been the standard in genomics for decades. In this article, we have put together various repository options available for proteomics data. We have also added pros and cons of those repositories to facilitate researchers in selecting the repository most suitable for their data submission. It is also important to note that a few types of proteomics data have the potential to re-identify an individual in certain scenarios. In such cases, extra caution should be taken to remove any personal identifiers before sharing on public repositories. Data sets that will be useless without personal identifiers need to be shared in a controlled access repository so that only authorized researchers can access the data and personal identifiers are kept safe.


Assuntos
Privacidade , Proteômica , Humanos , Genômica , Metadados , Disseminação de Informação
9.
Proc Natl Acad Sci U S A ; 120(38): e2301456120, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37695907

RESUMO

The Mott metal-insulator transition represents one of the most fundamental phenomena in condensed matter physics. Yet, basic tenets of the canonical Brinkman-Rice picture of Mott localization remain to be tested experimentally by quantum oscillation measurements that directly probe the quasiparticle Fermi surface and effective mass. By extending this technique to high pressure, we have examined the metallic state on the threshold of Mott localization in clean, undoped crystals of NiS2. We find that i) on approaching Mott localization, the quasiparticle mass is strongly enhanced, whereas the Fermi surface remains essentially unchanged; ii) the quasiparticle mass closely follows the divergent form predicted theoretically, establishing charge carrier slowdown as the driver for the metal-insulator transition; iii) this mass divergence is truncated by the metal-insulator transition, placing the Mott critical point inside the insulating section of the phase diagram. The inaccessibility of the Mott critical point in NiS2 parallels findings at the threshold of ferromagnetism in clean metallic systems, in which criticality at low temperature is almost universally interrupted by first-order transitions or novel emergent phases such as incommensurate magnetic order or unconventional superconductivity.

10.
Proc Natl Acad Sci U S A ; 120(12): e2216030120, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36927154

RESUMO

Network link inference from measured time series data of the behavior of dynamically interacting network nodes is an important problem with wide-ranging applications, e.g., estimating synaptic connectivity among neurons from measurements of their calcium fluorescence. Network inference methods typically begin by using the measured time series to assign to any given ordered pair of nodes a numerical score reflecting the likelihood of a directed link between those two nodes. In typical cases, the measured time series data may be subject to limitations, including limited duration, low sampling rate, observational noise, and partial nodal state measurement. However, it is unknown how the performance of link inference techniques on such datasets depends on these experimental limitations of data acquisition. Here, we utilize both synthetic data generated from coupled chaotic systems as well as experimental data obtained from Caenorhabditis elegans neural activity to systematically assess the influence of data limitations on the character of scores reflecting the likelihood of a directed link between a given node pair. We do this for three network inference techniques: Granger causality, transfer entropy, and, a machine learning-based method. Furthermore, we assess the ability of appropriate surrogate data to determine statistical confidence levels associated with the results of link-inference techniques.


Assuntos
Caenorhabditis elegans , Cálcio , Animais , Cálcio da Dieta , Fatores de Tempo , Neurônios/fisiologia
11.
Circulation ; 149(19): e1134-e1142, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38545775

RESUMO

Wearable biosensors (wearables) enable continual, noninvasive physiologic and behavioral monitoring at home for those with pediatric or congenital heart disease. Wearables allow patients to access their personal data and monitor their health. Despite substantial technologic advances in recent years, issues with hardware design, data analysis, and integration into the clinical workflow prevent wearables from reaching their potential in high-risk congenital heart disease populations. This science advisory reviews the use of wearables in patients with congenital heart disease, how to improve these technologies for clinicians and patients, and ethical and regulatory considerations. Challenges related to the use of wearables are common to every clinical setting, but specific topics for consideration in congenital heart disease are highlighted.


Assuntos
American Heart Association , Técnicas Biossensoriais , Cardiopatias Congênitas , Dispositivos Eletrônicos Vestíveis , Humanos , Cardiopatias Congênitas/diagnóstico , Técnicas Biossensoriais/instrumentação , Estados Unidos
12.
Circulation ; 149(6): e296-e311, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38193315

RESUMO

Multiple applications for machine learning and artificial intelligence (AI) in cardiovascular imaging are being proposed and developed. However, the processes involved in implementing AI in cardiovascular imaging are highly diverse, varying by imaging modality, patient subtype, features to be extracted and analyzed, and clinical application. This article establishes a framework that defines value from an organizational perspective, followed by value chain analysis to identify the activities in which AI might produce the greatest incremental value creation. The various perspectives that should be considered are highlighted, including clinicians, imagers, hospitals, patients, and payers. Integrating the perspectives of all health care stakeholders is critical for creating value and ensuring the successful deployment of AI tools in a real-world setting. Different AI tools are summarized, along with the unique aspects of AI applications to various cardiac imaging modalities, including cardiac computed tomography, magnetic resonance imaging, and positron emission tomography. AI is applicable and has the potential to add value to cardiovascular imaging at every step along the patient journey, from selecting the more appropriate test to optimizing image acquisition and analysis, interpreting the results for classification and diagnosis, and predicting the risk for major adverse cardiac events.


Assuntos
American Heart Association , Inteligência Artificial , Humanos , Aprendizado de Máquina , Coração , Imageamento por Ressonância Magnética
13.
Circulation ; 149(3): 251-266, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38227718

RESUMO

Coronary artery calcification (CAC) accompanies the development of advanced atherosclerosis. Its role in atherosclerosis holds great interest because the presence and burden of coronary calcification provide direct evidence of the presence and extent of coronary artery disease; furthermore, CAC predicts future events independently of concomitant conventional cardiovascular risk factors and to a greater extent than any other noninvasive biomarker of this disease. Nevertheless, the relationship between CAC and the susceptibility of a plaque to provoke a thrombotic event remains incompletely understood. This review summarizes the current understanding and literature on CAC. It outlines the pathophysiology of CAC and reviews laboratory, histopathological, and genetic studies, as well as imaging findings, to characterize different types of calcification and to elucidate their implications. Some patterns of calcification such as microcalcification portend increased risk of rupture and cardiovascular events and may improve prognosis assessment noninvasively. However, contemporary computed tomography cannot assess early microcalcification. Limited spatial resolution and blooming artifacts may hinder estimation of degree of coronary artery stenosis. Technical advances such as photon counting detectors and combination with nuclear approaches (eg, NaF imaging) promise to improve the performance of cardiac computed tomography. These innovations may speed achieving the ultimate goal of providing noninvasively specific and clinically actionable information.


Assuntos
Aterosclerose , Calcinose , Doença da Artéria Coronariana , Calcificação Vascular , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/complicações , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Angiografia Coronária/métodos , Medição de Risco , Aterosclerose/patologia , Calcinose/diagnóstico por imagem , Calcinose/patologia , Calcificação Vascular/patologia , Fatores de Risco
14.
Brief Bioinform ; 24(1)2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36516298

RESUMO

This paper describes a method Pprint2, which is an improved version of Pprint developed for predicting RNA-interacting residues in a protein. Training and independent/validation datasets used in this study comprises of 545 and 161 non-redundant RNA-binding proteins, respectively. All models were trained on training dataset and evaluated on the validation dataset. The preliminary analysis reveals that positively charged amino acids such as H, R and K, are more prominent in the RNA-interacting residues. Initially, machine learning based models have been developed using binary profile and obtain maximum area under curve (AUC) 0.68 on validation dataset. The performance of this model improved significantly from AUC 0.68 to 0.76, when evolutionary profile is used instead of binary profile. The performance of our evolutionary profile-based model improved further from AUC 0.76 to 0.82, when convolutional neural network has been used for developing model. Our final model based on convolutional neural network using evolutionary information achieved AUC 0.82 with Matthews correlation coefficient of 0.49 on the validation dataset. Our best model outperforms existing methods when evaluated on the independent/validation dataset. A user-friendly standalone software and web-based server named 'Pprint2' has been developed for predicting RNA-interacting residues (https://webs.iiitd.edu.in/raghava/pprint2 and https://github.com/raghavagps/pprint2).


Assuntos
Aminoácidos , RNA , Sítios de Ligação , RNA/metabolismo , Software , Proteínas de Ligação a RNA/metabolismo
15.
Mass Spectrom Rev ; 43(3): 427-476, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37070280

RESUMO

Ever since the inception of synthetic polymeric materials in the late 19th century, the number of studies on polymers as well as the complexity of their structures have only increased. The development and commercialization of new polymers with properties fine-tuned for specific technological, environmental, consumer, or biomedical applications requires powerful analytical techniques that permit the in-depth characterization of these materials. One such method with the ability to provide chemical composition and structure information with high sensitivity, selectivity, specificity, and speed is mass spectrometry (MS). This tutorial review presents and exemplifies the various MS techniques available for the elucidation of specific structural features in a synthetic polymer, including compositional complexity, primary structure, architecture, topology, and surface properties. Key to every MS analysis is sample conversion to gas-phase ions. This review describes the fundamentals of the most suitable ionization methods for synthetic materials and provides relevant sample preparation protocols. Most importantly, structural characterizations via one-step as well as hyphenated or multidimensional approaches are introduced and demonstrated with specific applications, including surface sensitive and imaging techniques. The aim of this tutorial review is to illustrate the capabilities of MS for the characterization of large, complex polymers and emphasize its potential as a powerful compositional and structural elucidation tool in polymer chemistry.

16.
Arterioscler Thromb Vasc Biol ; 44(7): 1523-1536, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38695171

RESUMO

The implementation of human induced pluripotent stem cell (hiPSC) models has introduced an additional tool for identifying molecular mechanisms of disease that complement animal models. Patient-derived or CRISPR/Cas9-edited induced pluripotent stem cells differentiated into smooth muscle cells (SMCs) have been leveraged to discover novel mechanisms, screen potential therapeutic strategies, and model in vivo development. The field has evolved over almost 15 years of research using hiPSC-SMCs and has made significant strides toward overcoming initial challenges such as the lineage specificity of SMC phenotypes. However, challenges both specific (eg, the lack of specific markers to thoroughly validate hiPSC-SMCs) and general (eg, a lack of transparency and consensus around methodology in the field) remain. In this review, we highlight the recent successes and remaining challenges of the hiPSC-SMC model.


Assuntos
Diferenciação Celular , Células-Tronco Pluripotentes Induzidas , Miócitos de Músculo Liso , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Miócitos de Músculo Liso/patologia , Miócitos de Músculo Liso/metabolismo , Animais , Fenótipo , Músculo Liso Vascular/patologia , Músculo Liso Vascular/metabolismo , Linhagem da Célula
17.
Methods ; 222: 19-27, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38141869

RESUMO

The International Classification of Diseases (ICD) serves as a global healthcare administration standard, with one of its editions being ICD-10-CM, an enhanced diagnostic classification system featuring numerous new codes for specific anatomic sites, co-morbidities, and causes. These additions facilitate conveying the complexities of various diseases. Currently, ICD-10 coding is widely adopted worldwide. However, public hospitals in Pakistan have yet to implement it and automate the coding process. In this research, we implemented ICD-10-CM coding for a private database and named it Clinical Pool of Liver Transplant (CPLT). Additionally, we proposed a novel deep learning model called Deep Recurrent-Convolution Neural Network with a lambda-scaled Attention module (DRCNN-ATT) using the CPLT database to achieve automatic ICD-10-CM coding. DRCNN-ATT combines a bi-directional long short-term memory network (bi-LSTM), a multi-scale convolutional neural network (MS-CNN), and a lambda-scaled attention module. Experimental results demonstrate that deep recurrent convolutional neural network (DRCNN) faces attention score vanishing problem with a standard attention module for automatic ICD coding. However, adding a lambda-scaled attention module resolves this issue. We evaluated DRCNN-ATT model using two distinct datasets: a private CPLT dataset and a public MIMIC III top 50 dataset. The results indicate that the DRCNN-ATT model outperformed various baselines by generating 0.862 micro F1 and 0.25 macro F1 scores on CPLT dataset and 0.705 micro F1 and 0.655 macro F1 scores on MIMIC III top 50 dataset. Furthermore, we also deployed our model for automatic ICD-10-CM coding using ngrok and the Flask APIs, which receives input, processes it, and then returns the results.


Assuntos
Aprendizado Profundo , Classificação Internacional de Doenças , Redes Neurais de Computação
18.
Nature ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816474
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