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1.
Nat Methods ; 21(3): 521-530, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38366241

RESUMO

Spatial omics technologies can reveal the molecular intricacy of the brain. While mass spectrometry imaging (MSI) provides spatial localization of compounds, comprehensive biochemical profiling at a brain-wide scale in three dimensions by MSI with single-cell resolution has not been achieved. We demonstrate complementary brain-wide and single-cell biochemical mapping using MEISTER, an integrative experimental and computational mass spectrometry (MS) framework. Our framework integrates a deep-learning-based reconstruction that accelerates high-mass-resolving MS by 15-fold, multimodal registration creating three-dimensional (3D) molecular distributions and a data integration method fitting cell-specific mass spectra to 3D datasets. We imaged detailed lipid profiles in tissues with millions of pixels and in large single-cell populations acquired from the rat brain. We identified region-specific lipid contents and cell-specific localizations of lipids depending on both cell subpopulations and anatomical origins of the cells. Our workflow establishes a blueprint for future development of multiscale technologies for biochemical characterization of the brain.


Assuntos
Aprendizado Profundo , Ratos , Animais , Espectrometria de Massas/métodos , Encéfalo , Lipídeos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
2.
Nature ; 598(7882): 646-651, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34646022

RESUMO

µ-Opioid peptide receptor (MOPR) stimulation alters respiration, analgesia and reward behaviour, and can induce substance abuse and overdose1-3. Despite its evident importance, the endogenous mechanisms for MOPR regulation of consummatory behaviour have remained unknown4. Here we report that endogenous MOPR regulation of reward consumption in mice acts through a specific dorsal raphe to nucleus accumbens projection. MOPR-mediated inhibition of raphe terminals is necessary and sufficient to determine consummatory response, while select enkephalin-containing nucleus accumbens ensembles are engaged prior to reward consumption, suggesting that local enkephalin release is the source of the endogenous MOPR ligand. Selective modulation of nucleus accumbens enkephalin neurons and CRISPR-Cas9-mediated disruption of enkephalin substantiate this finding. These results isolate a fundamental endogenous opioid circuit for state-dependent consumptive behaviour and suggest alternative mechanisms for opiate modulation of reward.


Assuntos
Analgésicos Opioides/farmacologia , Núcleo Accumbens/fisiologia , Receptores Opioides mu/fisiologia , Recompensa , Animais , Encefalinas , Feminino , Masculino , Camundongos , Camundongos Knockout
3.
Annu Rev Neurosci ; 41: 453-473, 2018 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-29852083

RESUMO

Opioids are the most commonly used and effective analgesic treatments for severe pain, but they have recently come under scrutiny owing to epidemic levels of abuse and overdose. These compounds act on the endogenous opioid system, which comprises four G protein-coupled receptors (mu, delta, kappa, and nociceptin) and four major peptide families (ß-endorphin, enkephalins, dynorphins, and nociceptin/orphanin FQ). In this review, we first describe the functional organization and pharmacology of the endogenous opioid system. We then summarize current knowledge on the signaling mechanisms by which opioids regulate neuronal function and neurotransmission. Finally, we discuss the loci of opioid analgesic action along peripheral and central pain pathways, emphasizing the pain-relieving properties of opioids against the affective dimension of the pain experience.


Assuntos
Analgésicos Opioides/metabolismo , Analgésicos Opioides/uso terapêutico , Dor/tratamento farmacológico , Dor/metabolismo , Animais , Humanos , Percepção da Dor , Receptores Acoplados a Proteínas G/metabolismo
4.
J Clin Microbiol ; 62(3): e0149823, 2024 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-38315022

RESUMO

Sepsis caused by bloodstream infection (BSI) is a major healthcare burden and a leading cause of morbidity and mortality worldwide. Timely diagnosis is critical to optimize clinical outcome, as mortality rates rise every hour treatment is delayed. Blood culture remains the "gold standard" for diagnosis but is limited by its long turnaround time (1-7 days depending on the organism) and its potential to provide false-negative results due to interference by antimicrobial therapy or the presence of mixed (i.e., polymicrobial) infections. In this paper, we evaluated the performance of resistance and pathogen ID/BSI, a direct-from-specimen molecular assay. To reduce the false-positivity rate common with molecular methods, this assay isolates and detects genomic material only from viable microorganisms in the blood by incorporating a novel precursor step to selectively lyse host and non-viable microbial cells and remove cell-free genomic material prior to lysis and analysis of microbial cells. Here, we demonstrate that the assay is free of interference from host immune cells and common antimicrobial agents at elevated concentrations. We also demonstrate the accuracy of this technology in a prospective cohort pilot study of individuals with known sepsis/BSI status, including samples from both positive and negative individuals. IMPORTANCE: Blood culture remains the "gold standard" for the diagnosis of sepsis/bloodstream infection (BSI) but has many limitations which may lead to a delay in appropriate and accurate treatment in patients. Molecular diagnostic methods have the potential for markedly improving the management of such patients through faster turnaround times and increased accuracy. But molecular diagnostic methods have not been widely adopted for the identification of BSIs. By incorporating a precursor step of selective lysis of host and non-viable microorganisms, our resistance and pathogen ID (RaPID)/BSI molecular assay addresses many limitations of blood culture and other molecular assay. The RaPID/BSI assay has an approximate turnaround time of 4 hours, thereby significantly reducing the time to appropriate and accurate diagnosis of causative microorganisms in such patients. The short turnaround time also allows for close to real-time tracking of pathogenic clearance of microorganisms from the blood of these patients or if a change of antimicrobial regimen is required. Thus, the RaPID/BSI molecular assay helps with optimization of antimicrobial stewardship; prompt and accurate diagnosis of sepsis/BSI could help target timely treatment and reduce mortality and morbidity in such patients.


Assuntos
Anti-Infecciosos , Bacteriemia , Infecções Bacterianas , Doenças Transmissíveis , Sepse , Humanos , Projetos Piloto , Sepse/diagnóstico , Bacteriemia/diagnóstico
5.
Nat Methods ; 18(10): 1233-1238, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34594032

RESUMO

Peptidergic dense-core vesicles are involved in packaging and releasing neuropeptides and peptide hormones-critical processes underlying brain, endocrine and exocrine function. Yet, the heterogeneity within these organelles, even for morphologically defined vesicle types, is not well characterized because of their small volumes. We present image-guided, high-throughput mass spectrometry-based protocols to chemically profile large populations of both dense-core vesicles and lucent vesicles for their lipid and peptide contents, allowing observation of the chemical heterogeneity within and between these two vesicle populations. The proteolytic processing products of four prohormones are observed within the dense-core vesicles, and the mass spectral features corresponding to the specific peptide products suggest three distinct dense-core vesicle populations. Notable differences in the lipid mass range are observed between the dense-core and lucent vesicles. These single-organelle mass spectrometry approaches are adaptable to characterize a range of subcellular structures.


Assuntos
Aplysia/citologia , Ensaios de Triagem em Larga Escala/métodos , Aprendizado de Máquina , Organelas/fisiologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Animais
6.
Mass Spectrom Rev ; 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37010120

RESUMO

Exploring the chemical content of individual cells not only reveals underlying cell-to-cell chemical heterogeneity but is also a key component in understanding how cells combine to form emergent properties of cellular networks and tissues. Recent technological advances in many analytical techniques including mass spectrometry (MS) have improved instrumental limits of detection and laser/ion probe dimensions, allowing the analysis of micron and submicron sized areas. In the case of MS, these improvements combined with MS's broad analyte detection capabilities have enabled the rise of single-cell and single-organelle chemical characterization. As the chemical coverage and throughput of single-cell measurements increase, more advanced statistical and data analysis methods have aided in data visualization and interpretation. This review focuses on secondary ion MS and matrix-assisted laser desorption/ionization MS approaches for single-cell and single-organelle characterization, which is followed by advances in mass spectral data visualization and analysis.

7.
Nicotine Tob Res ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538080

RESUMO

INTRODUCTION: This study assessed the efficacy of the SinHumo App combined with a cognitive-behavioral smoking cessation treatment on 12-month follow-up abstinence, compared with the same smoking cessation treatment and a control App. AIMS AND METHODS: A sample of 288 treatment-seeking people who smoke were randomized: SinHumo App plus smoking cessation treatment (n = 140) and control App plus smoking cessation treatment (n = 148). The primary outcome was 7-day point prevalence abstinence (PPA) at the 12-month follow-up. Secondary outcomes were abstinence rates at the end of the intervention and 3- and 6-month follow-ups, cigarette per day (CPD) reduction over the 12-month follow-up, intervention engagement, and satisfaction. RESULTS: Intention-to-treat analyses showed nonsignificant differences in self-reported 7-day PPA at the 12-month follow-up (37.1 and 42.6%, respectively; OR = 0.80). No significant differences were found in abstinence at the end of the treatment (68.6 vs. 62.8%) nor on 7-day PPA at 3- (35.7 vs. 45.9%) and 6-month (35.0 vs. 41.2%) follow-up. Complete case and multiple imputation analyses yielded similar results for abstinence outcomes. A significant reduction in CPD across the 12-month follow-up in the subsample of participants who smoked was observed, but nonsignificant differences between conditions were found. Higher engagement with the SinHumo App was a significant predictor of 12-month abstinence. Satisfaction with the intervention was high and similar in both groups. CONCLUSIONS: High abstinence rates over the 12-month follow-up and satisfaction were found in both conditions. The inclusion of the SinHumo App did not improve abstinence rates in the intervention. IMPLICATIONS: Scarce research has examined the long-term efficacy of smoking cessation treatments, including Apps, to support the quitting process. The present randomized controlled trial contributes to the existing literature about including information and communication technologies in behavior change interventions. The development of effective smoking cessation apps and information and communication technologies-based interventions is crucial for reducing the prevalence of smoking, as these interventions have the potential to reach a large number of people who smoke and reduce access-related barriers to treatment.

8.
BMC Med Ethics ; 25(1): 68, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858731

RESUMO

BACKGROUND: Q-CEP (Qualificação dos Comitês de Ética em Pesquisa que compõem o Sistema CEP/Conep) is a nationwide project resulting from a partnership between the Brazilian National Research Ethics Commission (Conep), the Ministry of Health and Hospital Moinhos de Vento (HMV). It was developed to consolidate policy for ethical review of research with human beings in all members of the CEP/Conep System, Brazil's national system of institutional review boards. The aim of this study was therefore to report on the experience and results of the Q-CEP project. METHODS: An observational, retrospective study includes data from the Q-CEP, obtained from visits to all the institutional research ethics committees (RECs) in the country. The actions implemented by Q-CEP were part of a two-step process: (i) training visits to each REC; (ii) development of distance learning modules on strategic topics pertaining to research ethics evaluation. The data presented herein cover step one (training visits), defined by Q-CEP as the diagnostic stage of the project. For a country with social and economics inequalities such as Brazil, this is a particularly important stage; an accurate picture of reality is needed to inform planning of quality improvement strategies. RESULTS: In 2019-2021, Q-CEP visited 832 RECs and trained 11,197 people. This sample covered almost all active RECs in the country; only 4 (0.5%) were not evaluated. Of the 94 items evaluated, 62% did not reach the target of at least 80% compliance and around 1/4 (26%) were below 50% compliance. The diagnostic stage of the process revealed inadequacies on the part of the RECs in their ethical reviews. The analysis of informed consent forms showed compliance in only 131 RECs (15.74%). The description of pending issues made by RECs in their reports was compliant in 19.33% (n = 161). Administrative and operational aspects were also considered inadequate by more than half of the RECs. CONCLUSIONS: Overall, Brazilian RECs showed poor compliance in several aspects of their operation, both in ethics evaluation and in other processes, which justifies additional training. The Q-CEP project is part of a quality improvement policy promoted by the Brazilian Ministry of Health. The data obtained in the diagnostic step of the project have contributed to the qualification and consolidation of one of the world's largest research ethics evaluation systems.


Assuntos
Pesquisa Biomédica , Comitês de Ética em Pesquisa , Ética em Pesquisa , Melhoria de Qualidade , Brasil , Humanos , Pesquisa Biomédica/ética , Estudos Retrospectivos
9.
Int J Paediatr Dent ; 34(1): 11-25, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37101236

RESUMO

BACKGROUND: Fluoride varnish (FV) is widely recommended for caries prevention in preschool children, despite its anticaries benefits being uncertain and modest. Dentists often report using clinical practice guidelines (CPGs) as a source of scientific information. AIM: To identify and analyze recommendations for clinical practice on the use of FV for caries prevention in preschool children and to assess the methodological quality of the CPG on this topic. DESIGN: Two researchers independently used 12 search strategies and searched the first five pages of Google Search™ and three guideline databases for recommendations freely available to health professionals on the use of FV for caries prevention in preschoolers. Then, they retrieved and recorded recommendations that met the eligibility criteria and extracted the data. A third researcher resolved disagreements. Each included CPG was appraised using the AGREE II instrument. RESULTS: Twenty-nine documents were included. Recommendations varied according to age, patients' caries risk, and application frequency. Of the six CPGs, only one scored above 70% in the AGREE II overall assessment. CONCLUSION: Recommendations on the use of FV lacked scientific evidence, and CPGs were of poor quality. Application of FV is widely recommended despite recent evidence showing an uncertain, modest, and possibly not clinically relevant anticaries benefit. Dentists should be aware that it is necessary to critically appraise CPGs since they may be of poor quality.


Assuntos
Cárie Dentária , Fluoretos , Humanos , Pré-Escolar , Fluoretos Tópicos/uso terapêutico , Cariostáticos/uso terapêutico , Suscetibilidade à Cárie Dentária , Cárie Dentária/prevenção & controle , Cárie Dentária/tratamento farmacológico
10.
Gastroenterol Hepatol ; 47(2): 119-129, 2024 Feb.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-36870477

RESUMO

INTRODUCTION AND AIMS: The outcomes of endoscopic submucosal dissection (ESD) in the esophagus have not been assessed in our country. Our primary aim was to analyze the effectiveness and safety of the technique. MATERIAL AND METHODS: Analysis of the prospectively maintained national registry of ESD. We included all superficial esophageal lesions removed by ESD in 17 hospitals (20 endoscopists) between January 2016 and December 2021. Subepithelial lesions were excluded. The primary outcome was curative resection. We conducted a survival analysis and used logistic regression analysis to assess predictors of non-curative resection. RESULTS: A total of 102 ESD were performed on 96 patients. The technical success rate was 100% and the percentage of en-bloc resection was 98%. The percentage of R0 and curative resection was 77.5% (n=79; 95%CI: 68%-84%) and 63.7% (n=65; 95%CI: 54%-72%), respectively. The most frequent histology was Barrett-related neoplasia (n=55 [53.9%]). The main reason for non-curative resection was deep submucosal invasion (n=25). The centers with a lower volume of ESD obtained worse results in terms of curative resection. The rate of perforation, delayed bleeding and post-procedural stenosis were 5%, 5% and 15.7%, respectively. No patient died or required surgery due to an adverse effect. After a median follow-up of 14months, 20patients (20.8%) underwent surgery and/or chemoradiotherapy, and 9 patients died (mortality 9.4%). CONCLUSIONS: In Spain, esophageal ESD is curative in approximately two out of three patients, with an acceptable risk of adverse events.


Assuntos
Ressecção Endoscópica de Mucosa , Neoplasias Esofágicas , Humanos , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/patologia , Ressecção Endoscópica de Mucosa/efeitos adversos , Ressecção Endoscópica de Mucosa/métodos , Espanha , Resultado do Tratamento , Estudos Retrospectivos
11.
J Proteome Res ; 22(2): 491-500, 2023 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-36695570

RESUMO

Improved throughput of analysis and lowered limits of detection have allowed single-cell chemical analysis to go beyond the detection of a few molecules in such volume-limited samples, enabling researchers to characterize different functional states of individual cells. Image-guided single-cell mass spectrometry leverages optical and fluorescence microscopy in the high-throughput analysis of cellular and subcellular targets. In this work, we propose DATSIGMA (DAta-driven Tools for Single-cell analysis using Image-Guided MAss spectrometry), a workflow based on data-driven and machine learning approaches for feature extraction and enhanced interpretability of complex single-cell mass spectrometry data. Here, we implemented our toolset with user-friendly programs and tested it on multiple experimental data sets that cover a wide range of biological applications, including classifying various brain cell types. Because it is open-source, it offers a high level of customization and can be easily adapted to other types of single-cell mass spectrometry data.


Assuntos
Aprendizado de Máquina , Análise de Célula Única , Espectrometria de Massas/métodos , Fluxo de Trabalho , Análise de Célula Única/métodos , Encéfalo
12.
Anal Chem ; 95(17): 6980-6988, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37070980

RESUMO

The mammalian brain contains ∼20,000 distinct lipid species that contribute to its structural organization and function. The lipid profiles of cells change in response to a variety of cellular signals and environmental conditions that result in modulation of cell function through alteration of phenotype. The limited sample material combined with the vast chemical diversity of lipids makes comprehensive lipid profiling of individual cells challenging. Here, we leverage the resolving power of a 21 T Fourier-transform ion cyclotron resonance (FTICR) mass spectrometer for chemical characterization of individual hippocampal cells at ultrahigh mass resolution. The accuracy of the acquired data allowed differentiation of freshly isolated and cultured hippocampal cell populations, as well as finding differences in lipids between the soma and neuronal processes of the same cell. Differences in lipids include TG 42:2 observed solely in the cell bodies and SM 34:1;O2 found only in the cellular processes. The work represents the first mammalian single cells analyzed at ultrahigh resolution and is an advance in the performance of mass spectrometry (MS) for single-cell research.


Assuntos
Ciclotrons , Lipídeos , Animais , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Análise de Fourier , Mamíferos
13.
Phys Rev Lett ; 130(17): 178101, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37172258

RESUMO

We consider planar liquid crystal elastomers: two-dimensional objects made of anisotropic responsive materials that remain flat when stimulated, however change their planar shape. We derive a closed form, analytical solution based on the implicit linearity featured by this subclass of deformations. Our solution provides the nematic director field on an arbitrary domain starting with two initial director curves. We discuss the different gauge choices for this problem and the inclusion of disclinations in the nematic order. Finally, we propose several applications and useful design principles based on this theoretical framework.

14.
Pacing Clin Electrophysiol ; 46(10): 1278-1286, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37695204

RESUMO

BACKGROUND: Embolic cerebrovascular events that remain of unknown etiology after a thorough diagnostic evaluation, are known as Embolic Strokes of Undetermined Source (ESUS). Subclinical atrial fibrillation (AF) represents a significant underlying cause of ESUS. Our aims were to examine the overall diagnostic yield of a prolonged cardiac monitoring wearable system (PCMw) after an ESUS to detect AF and factors associated with it, including the time frame from the ESUS event to PCMw initiation. Additionally, to evaluate the frequency of unexpected arrhythmic events (UAE) and their prognostic implications. METHODS: We retrospectively analyzed 200 ECG recordings (3-leads, 30 days duration) by means of a PCMw in patients with an ESUS to detect AF lasting longer than 30 s, between 2017 and 2021. UAE were defined as arrhythmia events that were not correlated to the main reason of prolonged cardiac monitoring. RESULTS: AF was detected in 21 patients (10.5%). Patients with AF had more left atrial enlargement (OR = 4.22 [1.59-6.85]; p = .01) and atrial arrythmias in the initial 24-h Holter during hospitalization (OR = 5.73 [2.03-16.49]; p = .001). The detection of AF was significatively higher if the PCMw was worn within the first 30 days after the ESUS compared to beyond 30 days (17% vs. 10.3%; p = .002). Fifty three patients (26.5%) had UAE during PCMw. In six of them these findings led to targeted treatment. CONCLUSION: PCMw represents a feasible non-invasive device that could reliably detect subclinical AF episodes after an ESUS. Diagnostic yield was significatively higher when used within the first 30 days after the event, especially in selected patients. UAE were common, but did not impact prognosis.

15.
Nano Lett ; 22(9): 3668-3677, 2022 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-35439419

RESUMO

The real-time monitoring of neurochemical release in vivo plays a critical role in understanding the biochemical process of the complex nervous system. Current technologies for such applications, including microdialysis and fast-scan cyclic voltammetry, suffer from limited spatiotemporal resolution or poor selectivity. Here, we report a soft implantable aptamer-graphene microtransistor probe for real-time monitoring of neurochemical release. As a demonstration, we show the monitoring of dopamine with nearly cellular-scale spatial resolution, high selectivity (dopamine sensor >19-fold over norepinephrine), and picomolar sensitivity, simultaneously. Systematic benchtop evaluations, ex vivo experiments, and in vivo studies in mice models highlight the key features and demonstrate the capability of capturing the dopamine release dynamics evoked by pharmacological stimulation, suggesting the potential applications in basic neuroscience studies and studying neurological disease-related processes. The developed system can be easily adapted for monitoring other neurochemicals and drugs by simply replacing the aptamers functionalized on the graphene microtransistors.


Assuntos
Dopamina , Grafite , Animais , Camundongos , Norepinefrina , Oligonucleotídeos
16.
Adicciones ; 0(0): 1898, 2023 Nov 29.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-39033522

RESUMO

Therapeutic Communities (TC) are residential settings that provide psychosocial rehabilitation for substance-using individuals. In general, TCs have been proven effective, although a large part of the evidence is from studies with methodological shortcomings. Therefore, the aim of this systematic review was to evaluate the effectiveness of TCs in terms of relapse rates. The search used EBSCO, PubMed, and Web of Science up to July 29, 2021 and was based on the international Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Of the 94 studies, eight met selection criteria including a total of 2,064 participants from 40 TCs. Of the eight studies, seven were cohort studies and one was a randomized controlled trial (RCT). Findings reveal that TCs were effective in reducing substance use, although some uncertainty remains regarding the long-term persistence of the improvements. Thus, further research is necessary to compare relapse rates in TC programs for substance-related disorders.


Las Comunidades Terapéuticas (CT) son entornos residenciales que brindan rehabilitación psicosocial a las personas que consumen sustancias. En general, estas han demostrado su eficacia, aunque gran parte de la evidencia proviene de estudios con limitaciones metodológicas. Por tanto, el objetivo de la presente revisión sistemática fue evaluar los resultados de las CT en relación con las tasas de recaída. La búsqueda se realizó en EBSCO, PubMed y Web of Science con fecha límite del 29 de julio de 2021 y se basó en la declaración Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). De los 94 estudios encontrados, ocho cumplieron los criterios de selección, con un total de 2064 participantes de 40 CT. De los ocho estudios, siete eran estudios de cohortes y uno era un ensayo controlado aleatorizado. Los resultados revelan que las CT eran efectivas para reducir el consumo de sustancias, aunque persiste cierta incertidumbre con respecto a la persistencia a largo plazo. Se necesita más investigación que evalúe las tasas de recaída tras finalizar el tratamiento en las CT.

17.
Anal Chem ; 94(13): 5335-5343, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35324161

RESUMO

Mass spectrometry imaging (MSI) allows for untargeted mapping of the chemical composition of tissues with attomole detection limits. MSI using Fourier transform (FT)-based mass spectrometers, such as FT-ion cyclotron resonance (FT-ICR), grants the ability to examine the chemical space with unmatched mass resolution and mass accuracy. However, direct imaging of large tissue samples using FT-ICR is slow. In this work, we present an approach that combines the subspace modeling of ICR temporal signals with compressed sensing to accelerate high-resolution FT-ICR MSI. A joint subspace and spatial sparsity constrained model computationally reconstructs high-resolution MSI data from the sparsely sampled transients with reduced duration, allowing a significant reduction in imaging time. Simulation studies and experimental implementation of the proposed method in investigation of brain tissues demonstrate a 10-fold enhancement in throughput of FT-ICR MSI, without the need for instrumental or hardware modifications.


Assuntos
Ciclotrons , Diagnóstico por Imagem , Análise de Fourier , Espectrometria de Massas/métodos
18.
Pacing Clin Electrophysiol ; 45(7): 896-899, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35191070

RESUMO

We present the case of a 75-year-old woman with severe aortic stenosis and moderate left ventricular dysfunction, who underwent elective transcatheter aortic valve replacement. After the procedure, the patient developed a left bundle branch block and a long PR interval. For this reason, a dual chamber pacemaker with pacing in the left bundle branch area was implanted. On device interrogation, we confirmed the presence of functional atrial undersensing causing loss of ventricular electric resynchronization. This case highlights the importance of recognizing this problem and, by means of device reprogramming and pharmacological intervention, suggests a stepwise approach to solve it.


Assuntos
Marca-Passo Artificial , Substituição da Valva Aórtica Transcateter , Idoso , Arritmias Cardíacas , Bloqueio de Ramo/terapia , Estimulação Cardíaca Artificial , Eletrocardiografia , Feminino , Sistema de Condução Cardíaco , Humanos , Resultado do Tratamento
19.
J Trauma Stress ; 35(4): 1115-1128, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35246860

RESUMO

The nosographic structure of posttraumatic stress disorder (PTSD) remains unclear, and attempts to determine its symptomatic organization have been unsatisfactory. Several explanations have been suggested, and the impact of trauma type is receiving increasing attention. As little is known about the differential impact trauma type in the nosographic structure of PTSD, we explored the nosology of PTSD and the effect of trauma type on its symptomatic organization. We reanalyzed five cross-sectional psychopathological networks involving different trauma types, encompassing a broad range of traumatic events in veterans, war-related trauma in veterans, sexual abuse, terrorist attacks, and various traumatic events in refugees. The weighted topological overlap was used to estimate the networks and attribute weights to their links. Coexpression differential network analysis was used to identify the common and specific network structures of the connections across different trauma types and to determine the importance of symptoms across the networks. We found a set of symptoms with more common connections with other symptoms, suggesting that these might constitute the prototypical nosographic structure of PTSD. We also found a set of symptoms that had a high number of specific connections with other symptoms; these connections varied according to trauma type. The importance of symptoms across the common and specific networks was ascertained. The present findings offer new insights into the symptomatic organization of PTSD and support previous research on the impact of trauma type on the nosology of this disorder.


Assuntos
Refugiados , Transtornos de Estresse Pós-Traumáticos , Veteranos , Estudos Transversais , Humanos , Transtornos de Estresse Pós-Traumáticos/diagnóstico
20.
Proc Natl Acad Sci U S A ; 116(43): 21427-21437, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31601737

RESUMO

Pharmacology and optogenetics are widely used in neuroscience research to study the central and peripheral nervous systems. While both approaches allow for sophisticated studies of neural circuitry, continued advances are, in part, hampered by technology limitations associated with requirements for physical tethers that connect external equipment to rigid probes inserted into delicate regions of the brain. The results can lead to tissue damage and alterations in behavioral tasks and natural movements, with additional difficulties in use for studies that involve social interactions and/or motions in complex 3-dimensional environments. These disadvantages are particularly pronounced in research that demands combined optogenetic and pharmacological functions in a single experiment. Here, we present a lightweight, wireless, battery-free injectable microsystem that combines soft microfluidic and microscale inorganic light-emitting diode probes for programmable pharmacology and optogenetics, designed to offer the features of drug refillability and adjustable flow rates, together with programmable control over the temporal profiles. The technology has potential for large-scale manufacturing and broad distribution to the neuroscience community, with capabilities in targeting specific neuronal populations in freely moving animals. In addition, the same platform can easily be adapted for a wide range of other types of passive or active electronic functions, including electrical stimulation.


Assuntos
Optogenética/métodos , Farmacologia/métodos , Animais , Encéfalo/metabolismo , Química Encefálica , Channelrhodopsins/metabolismo , Estimulação Elétrica , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Optogenética/instrumentação , Farmacologia/instrumentação , Próteses e Implantes , Tecnologia sem Fio/instrumentação
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