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1.
Nat Methods ; 21(2): 213-216, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37500758

RESUMO

Quantitative evaluation of image segmentation algorithms is crucial in the field of bioimage analysis. The most common assessment scores, however, are often misinterpreted and multiple definitions coexist with the same name. Here we present the ambiguities of evaluation metrics for segmentation algorithms and show how these misinterpretations can alter leaderboards of influential competitions. We also propose guidelines for how the currently existing problems could be tackled.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador/métodos
2.
Brief Bioinform ; 25(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38483256

RESUMO

Numerous imaging techniques are available for observing and interrogating biological samples, and several of them can be used consecutively to enable correlative analysis of different image modalities with varying resolutions and the inclusion of structural or molecular information. Achieving accurate registration of multimodal images is essential for the correlative analysis process, but it remains a challenging computer vision task with no widely accepted solution. Moreover, supervised registration methods require annotated data produced by experts, which is limited. To address this challenge, we propose a general unsupervised pipeline for multimodal image registration using deep learning. We provide a comprehensive evaluation of the proposed pipeline versus the current state-of-the-art image registration and style transfer methods on four types of biological problems utilizing different microscopy modalities. We found that style transfer of modality domains paired with fully unsupervised training leads to comparable image registration accuracy to supervised methods and, most importantly, does not require human intervention.


Assuntos
Aprendizado Profundo , Humanos , Microscopia
3.
Cell ; 144(4): 539-50, 2011 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-21335236

RESUMO

Disassembly of nuclear pore complexes (NPCs) is a decisive event during mitotic entry in cells undergoing open mitosis, yet the molecular mechanisms underlying NPC disassembly are unknown. Using chemical inhibition and depletion experiments we show that NPC disassembly is a phosphorylation-driven process, dependent on CDK1 activity and supported by members of the NIMA-related kinase (Nek) family. We identify phosphorylation of the GLFG-repeat nucleoporin Nup98 as an important step in mitotic NPC disassembly. Mitotic hyperphosphorylation of Nup98 is accomplished by multiple kinases, including CDK1 and Neks. Nuclei carrying a phosphodeficient mutant of Nup98 undergo nuclear envelope breakdown slowly, such that both the dissociation of Nup98 from NPCs and the permeabilization of the nuclear envelope are delayed. Together, our data provide evidence for a phosphorylation-dependent mechanism underlying disintegration of NPCs during prophase. Moreover, we identify mitotic phosphorylation of Nup98 as a rate-limiting step in mitotic NPC disassembly.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Mitose , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Poro Nuclear/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Aspergillus/citologia , Proteína Quinase CDC2/metabolismo , Ciclo Celular , Núcleo Celular/metabolismo , Células HeLa , Humanos , Mutação , Quinase 1 Relacionada a NIMA , Membrana Nuclear/metabolismo , Fosforilação , Prófase
4.
Small ; : e2401472, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38863131

RESUMO

The pre-clinical validation of cell therapies requires monitoring the biodistribution of transplanted cells in tissues of host organisms. Real-time detection of these cells in the circulatory system and identification of their aggregation state is a crucial piece of information, but necessitates deep penetration and fast imaging with high selectivity, subcellular resolution, and high throughput. In this study, multiphoton-based in-flow detection of human stem cells in whole, unfiltered blood is demonstrated in a microfluidic channel. The approach relies on a multiphoton microscope with diffractive scanning in the direction perpendicular to the flow via a rapidly wavelength-swept laser. Stem cells are labeled with metal oxide harmonic nanoparticles. Thanks to their strong and quasi-instantaneous second harmonic generation (SHG), an imaging rate in excess of 10 000 frames per second is achieved with pixel dwell times of 1 ns, a duration shorter than typical fluorescence lifetimes yet compatible with SHG. Through automated cell identification and segmentation, morphological features of each individual detected event are extracted and cell aggregates are distinguished from isolated cells. This combination of high-speed multiphoton microscopy and high-sensitivity SHG nanoparticle labeling in turbid media promises the detection of rare cells in the bloodstream for assessing novel cell-based therapies.

5.
Nat Methods ; 18(11): 1294-1303, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34725485

RESUMO

Spheroids are three-dimensional cellular models with widespread basic and translational application across academia and industry. However, methodological transparency and guidelines for spheroid research have not yet been established. The MISpheroID Consortium developed a crowdsourcing knowledgebase that assembles the experimental parameters of 3,058 published spheroid-related experiments. Interrogation of this knowledgebase identified heterogeneity in the methodological setup of spheroids. Empirical evaluation and interlaboratory validation of selected variations in spheroid methodology revealed diverse impacts on spheroid metrics. To facilitate interpretation, stimulate transparency and increase awareness, the Consortium defines the MISpheroID string, a minimum set of experimental parameters required to report spheroid research. Thus, MISpheroID combines a valuable resource and a tool for three-dimensional cellular models to mine experimental parameters and to improve reproducibility.


Assuntos
Biomarcadores Tumorais/genética , Proliferação de Células , Bases de Conhecimento , Neoplasias/patologia , Software , Esferoides Celulares/patologia , Microambiente Tumoral , Técnicas de Cultura de Células/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/classificação , Neoplasias/metabolismo , RNA-Seq , Reprodutibilidade dos Testes , Esferoides Celulares/imunologia , Esferoides Celulares/metabolismo , Células Tumorais Cultivadas
6.
Brief Bioinform ; 23(1)2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-34962256

RESUMO

The pharmacological arsenal against the COVID-19 pandemic is largely based on generic anti-inflammatory strategies or poorly scalable solutions. Moreover, as the ongoing vaccination campaign is rolling slower than wished, affordable and effective therapeutics are needed. To this end, there is increasing attention toward computational methods for drug repositioning and de novo drug design. Here, multiple data-driven computational approaches are systematically integrated to perform a virtual screening and prioritize candidate drugs for the treatment of COVID-19. From the list of prioritized drugs, a subset of representative candidates to test in human cells is selected. Two compounds, 7-hydroxystaurosporine and bafetinib, show synergistic antiviral effects in vitro and strongly inhibit viral-induced syncytia formation. Moreover, since existing drug repositioning methods provide limited usable information for de novo drug design, the relevant chemical substructures of the identified drugs are extracted to provide a chemical vocabulary that may help to design new effective drugs.


Assuntos
Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , COVID-19 , Células Gigantes , Pirimidinas/farmacologia , SARS-CoV-2/metabolismo , Estaurosporina/análogos & derivados , Células A549 , COVID-19/metabolismo , Biologia Computacional , Avaliação Pré-Clínica de Medicamentos , Reposicionamento de Medicamentos , Células Gigantes/metabolismo , Células Gigantes/virologia , Humanos , Estaurosporina/farmacologia
7.
Chemistry ; 30(19): e202400024, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38197554

RESUMO

Small-molecule dyes are generally designed based on well-understood electronic effects. However, steric hindrance can promote excited-state geometric relaxation, increasing the difference between the positions of absorption and emission bands (the Stokes shift). Accordingly, we hypothesized that sterically induced central ring puckering in xanthene dyes could be used to systematically increase their Stokes shift. Through a combined experimental/quantum-chemical approach, we screened a group of (9-acylimino)-pyronin dyes with a perturbed central ring geometry. Our results showed that an atom with sp3 hybridization in position 10 of (9-acylimino)-pyronins induces central ring puckering and facilitates excited-state geometric relaxation, thereby markedly enhancing their Stokes shifts (by up to ~2000 cm-1). Thus, we prepared fluorescent (9-acylimino)-pyronin pH sensors, which showed a Stokes shift disparity between acid and base forms of up to ~8700 cm-1. Moreover, the concept of ring puckering-enhanced Stokes shift can be applied to a wide range of xanthene analogues found in the literature. Therefore, central ring puckering may be reliably used as a strategy for enhancing Stokes shifts in the rational design of dyes.

8.
Nucleic Acids Res ; 50(5): 2872-2888, 2022 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35150276

RESUMO

Ribosome assembly is an essential process that is linked to human congenital diseases and tumorigenesis. While great progress has been made in deciphering mechanisms governing ribosome biogenesis in eukaryotes, an inventory of factors that support ribosome synthesis in human cells is still missing, in particular regarding the maturation of the large 60S subunit. Here, we performed a genome-wide RNAi screen using an imaging-based, single cell assay to unravel the cellular machinery promoting 60S subunit assembly in human cells. Our screen identified a group of 310 high confidence factors. These highlight the conservation of the process across eukaryotes and reveal the intricate connectivity of 60S subunit maturation with other key cellular processes, including splicing, translation, protein degradation, chromatin organization and transcription. Intriguingly, we also identified a cluster of hits comprising metabolic enzymes of the polyamine synthesis pathway. We demonstrate that polyamines, which have long been used as buffer additives to support ribosome assembly in vitro, are required for 60S maturation in living cells. Perturbation of polyamine metabolism results in early defects in 60S but not 40S subunit maturation. Collectively, our data reveal a novel function for polyamines in living cells and provide a rich source for future studies on ribosome synthesis.


Assuntos
Poliaminas , Proteínas de Saccharomyces cerevisiae , Humanos , Poliaminas/metabolismo , Interferência de RNA , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Subunidades Ribossômicas Maiores de Eucariotos/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
9.
Int J Mol Sci ; 25(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38473730

RESUMO

The G-quadruplex is one of the non-canonical structures formed by nucleic acids, which can be formed by guanine-rich sequences. They became the focus of much research when they were found in several oncogene promoter regions and also in the telomeres. Later on, they were discovered in viruses as well. Various ligands have been developed in order to stabilize DNA G-quadruplexes, which were believed to have an anti-cancer or antiviral effect. We investigated three of these ligands, and whether they can also affect the stability of the G-quadruplex-forming sequences of the RNA genome of SARS-CoV-2. All three investigated oligonucleotides showed the G-quadruplex form. We characterized their stability and measured their thermodynamic parameters using the Förster resonance energy transfer method. The addition of the ligands caused an increase in the unfolding temperature, but this effect was smaller compared to that found earlier in the case of G-quadruplexes of the hepatitis B virus, which has a DNA genome.


Assuntos
Acridinas , COVID-19 , Compostos de Anéis Fundidos , Quadruplex G , Porfirinas , Humanos , SARS-CoV-2
10.
Glob Chang Biol ; 29(15): 4440-4452, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37303068

RESUMO

Dynamic Global Vegetation Models (DGVMs) provide a state-of-the-art process-based approach to study the complex interplay between vegetation and its physical environment. For example, they help to predict how terrestrial plants interact with climate, soils, disturbance and competition for resources. We argue that there is untapped potential for the use of DGVMs in ecological and ecophysiological research. One fundamental barrier to realize this potential is that many researchers with relevant expertize (ecology, plant physiology, soil science, etc.) lack access to the technical resources or awareness of the research potential of DGVMs. Here we present the Land Sites Platform (LSP): new software that facilitates single-site simulations with the Functionally Assembled Terrestrial Ecosystem Simulator, an advanced DGVM coupled with the Community Land Model. The LSP includes a Graphical User Interface and an Application Programming Interface, which improve the user experience and lower the technical thresholds for installing these model architectures and setting up model experiments. The software is distributed via version-controlled containers; researchers and students can run simulations directly on their personal computers or servers, with relatively low hardware requirements, and on different operating systems. Version 1.0 of the LSP supports site-level simulations. We provide input data for 20 established geo-ecological observation sites in Norway and workflows to add generic sites from public global datasets. The LSP makes standard model experiments with default data easily achievable (e.g., for educational or introductory purposes) while retaining flexibility for more advanced scientific uses. We further provide tools to visualize the model input and output, including simple examples to relate predictions to local observations. The LSP improves access to land surface and DGVM modelling as a building block of community cyberinfrastructure that may inspire new avenues for mechanistic ecosystem research across disciplines.


Assuntos
Clima , Ecossistema , Humanos , Fenômenos Fisiológicos Vegetais , Software , Plantas
11.
Cell Commun Signal ; 21(1): 333, 2023 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-37986165

RESUMO

BACKGROUND: Although interest in the role of extracellular vesicles (EV) in oncology is growing, not all potential aspects have been investigated. In this meta-analysis, data regarding (i) the EV proteome and (ii) the invasion and proliferation capacity of the NCI-60 tumor cell lines (60 cell lines from nine different tumor types) were analyzed using machine learning methods. METHODS: On the basis of the entire proteome or the proteins shared by all EV samples, 60 cell lines were classified into the nine tumor types using multiple logistic regression. Then, utilizing the Least Absolute Shrinkage and Selection Operator, we constructed a discriminative protein panel, upon which the samples were reclassified and pathway analyses were performed. These panels were validated using clinical data (n = 4,665) from Human Protein Atlas. RESULTS: Classification models based on the entire proteome, shared proteins, and discriminative protein panel were able to distinguish the nine tumor types with 49.15%, 69.10%, and 91.68% accuracy, respectively. Invasion and proliferation capacity of the 60 cell lines were predicted with R2 = 0.68 and R2 = 0.62 (p < 0.0001). The results of the Reactome pathway analysis of the discriminative protein panel suggest that the molecular content of EVs might be indicative of tumor-specific biological processes. CONCLUSION: Integrating in vitro EV proteomic data, cell physiological characteristics, and clinical data of various tumor types illuminates the diagnostic, prognostic, and therapeutic potential of EVs. Video Abstract.


Assuntos
Vesículas Extracelulares , Neoplasias , Humanos , Proteoma/metabolismo , Proteômica/métodos , Neoplasias/patologia , Proliferação de Células , Vesículas Extracelulares/metabolismo
12.
BMC Infect Dis ; 23(1): 330, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37194021

RESUMO

BACKGROUND: While others have reported severe acute respiratory syndrome-related coronavirus 2(SARS-CoV-2) seroprevalence studies in health care workers (HCWs), we leverage the use of a highly sensitive coronavirus antigen microarray to identify a group of seropositive health care workers who were missed by daily symptom screening that was instituted prior to any epidemiologically significant local outbreak. Given that most health care facilities rely on daily symptom screening as the primary method to identify SARS-CoV-2 among health care workers, here, we aim to determine how demographic, occupational, and clinical variables influence SARS-CoV-2 seropositivity among health care workers. METHODS: We designed a cross-sectional survey of HCWs for SARS-CoV-2 seropositivity conducted from May 15th to June 30th 2020 at a 418-bed academic hospital in Orange County, California. From an eligible population of 5,349 HCWs, study participants were recruited in two ways: an open cohort, and a targeted cohort. The open cohort was open to anyone, whereas the targeted cohort that recruited HCWs previously screened for COVID-19 or work in high-risk units. A total of 1,557 HCWs completed the survey and provided specimens, including 1,044 in the open cohort and 513 in the targeted cohort. Demographic, occupational, and clinical variables were surveyed electronically. SARS-CoV-2 seropositivity was assessed using a coronavirus antigen microarray (CoVAM), which measures antibodies against eleven viral antigens to identify prior infection with 98% specificity and 93% sensitivity. RESULTS: Among tested HCWs (n = 1,557), SARS-CoV-2 seropositivity was 10.8%, and risk factors included male gender (OR 1.48, 95% CI 1.05-2.06), exposure to COVID-19 outside of work (2.29, 1.14-4.29), working in food or environmental services (4.85, 1.51-14.85), and working in COVID-19 units (ICU: 2.28, 1.29-3.96; ward: 1.59, 1.01-2.48). Amongst 1,103 HCWs not previously screened, seropositivity was 8.0%, and additional risk factors included younger age (1.57, 1.00-2.45) and working in administration (2.69, 1.10-7.10). CONCLUSION: SARS-CoV-2 seropositivity is significantly higher than reported case counts even among HCWs who are meticulously screened. Seropositive HCWs missed by screening were more likely to be younger, work outside direct patient care, or have exposure outside of work.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Masculino , COVID-19/epidemiologia , Estudos Transversais , Pandemias , Estudos Soroepidemiológicos , Pessoal de Saúde , Anticorpos Antivirais
13.
BMC Pulm Med ; 23(1): 71, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36814243

RESUMO

BACKGROUND: Ablation of malignant pulmonary nodules is a novel therapeutic option for patients who cannot undergo surgery. Current transthoracic approaches cause pneumothorax and/or bleeding in a significant number of cases. OBJECTIVE: Our purpose with this study was to evaluate cryoablation under in vitro conditions with a commercially available cryosurgery system. METHODS: We used ballistic gelatin to model the thermal conduction of lung tissue. The cryoprobe was inserted in the ballistic gelatin with two thermal sensors, they were placed 0.5 cm and 1.0. cm from the probe, respectively, temperature was measured on both sides. We used single-, double- and triple-freeze protocols to see if we could freeze it to -20 °C. RESULTS: We achieved - 18.6 ± 3.26 °C on the closer sensor (sensor 1) and - 3.7 ± 4.61 °C on the sensor further away (sensor 2) after 15 min using the single-freeze protocol. Using the dual-freeze protocol, we achieved - 23.2 ± 2,23 °C on sensor 1 and - 16.5 ± 2.82 °C on sensor 2. With the triple-freeze protocol we obtained - 23.5 ± 2.38 °C on sensor 1 and - 19.05 ± 3.22 °C on sensor 2. CONCLUSION: With dual-freeze, values above - 20 °C were achieved using nearer sensor data, but a plateau phase occurred as with continuous freezing. Using triple freeze, we reached - 20 °C at a distance of 0.5 cm from the probe, but not at 1 cm; therefore, we did not expand the diameter of the predicted necrosis zone.


Assuntos
Criocirurgia , Nódulos Pulmonares Múltiplos , Humanos , Projetos Piloto , Gelatina , Criocirurgia/métodos , Congelamento , Necrose/patologia
14.
BMC Biol ; 20(1): 74, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35361222

RESUMO

BACKGROUND: Understanding the contribution of gene function in distinct organ systems to the pathogenesis of human diseases in biomedical research requires modifying gene expression through the generation of gain- and loss-of-function phenotypes in model organisms, for instance, the mouse. However, methods to modify both germline and somatic genomes have important limitations that prevent easy, strong, and stable expression of transgenes. For instance, while the liver is remarkably easy to target, nucleic acids introduced to modify the genome of hepatocytes are rapidly lost, or the transgene expression they mediate becomes inhibited due to the action of effector pathways for the elimination of exogenous DNA. Novel methods are required to overcome these challenges, and here we develop a somatic gene delivery technology enabling long-lasting high-level transgene expression in the entire hepatocyte population of mice. RESULTS: We exploit the fumarylacetoacetate hydrolase (Fah) gene correction-induced regeneration in Fah-deficient livers, to demonstrate that such approach stabilizes luciferase expression more than 5000-fold above the level detected in WT animals, following plasmid DNA introduction complemented by transposon-mediated chromosomal gene transfer. Building on this advancement, we created a versatile technology platform for performing gene function analysis in vivo in the mouse liver. Our technology allows the tag-free expression of proteins of interest and silencing of any arbitrary gene in the mouse genome. This was achieved by applying the HADHA/B endogenous bidirectional promoter capable of driving well-balanced bidirectional expression and by optimizing in vivo intronic artificial microRNA-based gene silencing. We demonstrated the particular usefulness of the technology in cancer research by creating a p53-silenced and hRas G12V-overexpressing tumor model. CONCLUSIONS: We developed a versatile technology platform for in vivo somatic genome editing in the mouse liver, which meets multiple requirements for long-lasting high-level transgene expression. We believe that this technology will contribute to the development of a more accurate new generation of tools for gene function analysis in mice.


Assuntos
Mutação com Ganho de Função , Edição de Genes , Animais , Fígado/metabolismo , Camundongos , Fenótipo , Tecnologia
15.
Int J Mol Sci ; 25(1)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38203583

RESUMO

The presence of a chiral or chirally perturbed chromophore in the molecule under investigation is a fundamental requirement for the appearance of a circular dichroism (CD) spectrum. For native and for most of the substituted cyclodextrins, this condition is not applicable, because although chiral, cyclodextrins lack a chromophore group and therefore have no characteristic CD spectra over 220 nm. The reason this method can be used is that if the guest molecule has a chromophore group and this is in the right proximity to the cyclodextrin, it becomes chirally perturbed. As a result, the complex will now provide a CD signal, and this phenomenon is called induced circular dichroism (ICD). The appearance of the ICD spectrum is clear evidence of the formation of the complex, and the spectral sign and intensity is a good predictor of the structure of the complex. By varying the concentration of cyclodextrin, the ICD signal changes, resulting in a saturation curve, and from these data, the stability constant can be calculated for a 1:1 complex. This article compares ICD and NMR spectroscopic and molecular modeling results of cyclodextrin complexes of four model compounds: nimesulide, fenbufen, fenoprofen, and bifonazole. The results obtained by the different methods show good agreement, and the structures estimated from the ICD spectra are supported by NMR data and molecular modeling.


Assuntos
Ciclodextrinas , Dicroísmo Circular , Fenoprofeno
16.
Int J Mol Sci ; 24(8)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37108706

RESUMO

The stability of host-guest complexes of two NSAID drugs with similar physicochemical properties, fenbufen and fenoprofen, was investigated by comparing induced circular dichroism and 1H nuclear magnetic resonance methods using eight cyclodextrins of different degrees of substitution and isomeric purity as guest compounds. These cyclodextrins include native ß-cyclodextrin (BCyD), 2,6-dimethyl-ß-cyclodextrin 50 (DIMEB50), 80 (DIMEB80) and 95% (DIMEB95) isomerically pure versions, low-methylated CRYSMEB, randomly methylated ß-cyclodextrin (RAMEB) and 4.5 and 6.3 average substitution grade hydroxypropyl-ß-cyclodextrin (HPBCyD). The stability constants obtained by the two methods show good agreement in most cases. For fenbufen complexes, there is a clear trend that the stability constant increases with the degree of substitution while isomer purity has a smaller effect on the magnitude of stability constants. A significant difference was found in the case of DIMEB50 when compared to DIMEB80/DIMEB95, while the latter two are similar. In the fenbufen-fenoprofen comparison, fenbufen, with its linear axis, gives a more stable complex, while fenoprofen shows lower constants and poorly defined trends.


Assuntos
Ciclodextrinas , beta-Ciclodextrinas , 2-Hidroxipropil-beta-Ciclodextrina , beta-Ciclodextrinas/química , Ciclodextrinas/química , Fenoprofeno/química , Ligantes , Espectroscopia de Ressonância Magnética/métodos
17.
Int J Mol Sci ; 24(3)2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36768492

RESUMO

The interaction between human serum albumin (HSA) and apremilast (APR), a novel antipsoriatic drug, was characterized by multimodal analytical techniques including high-performance liquid chromatography (HPLC), fluorescence spectroscopy and molecular docking for the first time. Using an HSA chiral stationary phase, the APR enantiomers were well separated, indicating enantioselective binding between the protein and the analytes. The influence of chromatographic parameters-type and concentration of the organic modifier, buffer type, pH, ionic strength of the mobile phase, flow rate and column temperature-on the chromatographic responses (retention factor and selectivity) was analyzed in detail. The results revealed that the eutomer S-APR bound to the protein to a greater extent than the antipode. The classical van 't Hoff method was applied for thermodynamic analysis, which indicated that the enantioseparation was enthalpy-controlled. The stability constants of the protein-enantiomer complexes, determined by fluorescence spectroscopy, were in accordance with the elution order observed in HPLC (KR-APR-HSA = 6.45 × 103 M-1, KS-APR-HSA = 1.04 × 104 M-1), showing that, indeed, the later-eluting S-APR displayed a stronger binding with HSA. Molecular docking was applied to study and analyze the interactions between HSA and the APR enantiomers at the atomic level. It was revealed that the most favored APR binding occurred at the border between domains I and II of HSA, and secondary interactions were responsible for the different binding strengths of the enantiomers.


Assuntos
Albumina Sérica Humana , Albumina Sérica , Humanos , Albumina Sérica Humana/metabolismo , Simulação de Acoplamento Molecular , Albumina Sérica/metabolismo , Estereoisomerismo , Cromatografia Líquida de Alta Pressão/métodos , Termodinâmica , Ligação Proteica , Sítios de Ligação , Espectrometria de Fluorescência
18.
Int J Mol Sci ; 24(11)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37298130

RESUMO

Diagnosing interstitial lung disease (ILD) can be a challenging process. New biomarkers may support diagnostic decisions. Elevated serum progranulin (PGRN) levels have been reported in liver fibrosis and dermatomyositis-associated acute interstitial pneumonia. Our aim was to assess the role of PGRN in the differential diagnosis of idiopathic pulmonary fibrosis (IPF) and other ILDs. Serum levels of PGRN were measured by enzyme-linked immunosorbent assay in stable IPF (n = 40), non-IPF ILD (n = 48) and healthy controls (n = 17). Patient characteristics, lung function, CO diffusion (DLCO), arterial blood gases, 6-min walk test, laboratory parameters and high-resolution (HR)CT pattern were assessed. In stable IPF, PGRN levels did not differ from healthy controls; however, serum PGRN levels were significantly higher in non-IPF ILD patients compared to healthy subjects and IPF (53.47 ± 15.38 vs. 40.99 ± 5.33 vs. 44.66 ± 7.77 ng/mL respectively; p < 0.01). The HRCT pattern of usual interstitial pneumonia (UIP) was associated with normal PGRN level, while for non-UIP patterns, significantly elevated PGRN level was measured. Elevated serum PGRN levels may be associated with non-IPF ILD, especially non-UIP patterns and might be helpful in cases of unclear radiological patterns in the differentiation between IPF and other ILDs.


Assuntos
Pneumonias Intersticiais Idiopáticas , Fibrose Pulmonar Idiopática , Doenças Pulmonares Intersticiais , Humanos , Progranulinas , Fibrose Pulmonar Idiopática/diagnóstico , Doenças Pulmonares Intersticiais/diagnóstico , Diagnóstico Diferencial , Pulmão
19.
Eur Respir J ; 59(5)2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34649975

RESUMO

Clinical trials evaluating the management of acute exacerbations of COPD assess heterogeneous outcomes, often omitting those that are clinically relevant or more important to patients. We have developed a core outcome set, a consensus-based minimum set of important outcomes that we recommend are evaluated in all future clinical trials on exacerbations management, to improve their quality and comparability. COPD exacerbations outcomes were identified through methodological systematic reviews and qualitative interviews with 86 patients from 11 countries globally. The most critical outcomes were prioritised for inclusion in the core outcome set through a two-round Delphi survey completed by 1063 participants (256 patients, 488 health professionals and 319 clinical academics) from 88 countries in five continents. Two global, multi-stakeholder, virtual consensus meetings were conducted to 1) finalise the core outcome set and 2) prioritise a single measurement instrument to be used for evaluating each of the prioritised outcomes. Consensus was informed by rigorous methodological systematic reviews. The views of patients with COPD were accounted for at all stages of the project. Survival, treatment success, breathlessness, quality of life, activities of daily living, the need for a higher level of care, arterial blood gases, disease progression, future exacerbations and hospital admissions, treatment safety and adherence were all included in the core outcome set. Focused methodological research was recommended to further validate and optimise some of the selected measurement instruments. The panel did not consider the prioritised set of outcomes and associated measurement instruments to be burdensome for patients and health professionals to use.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Qualidade de Vida , Atividades Cotidianas , Técnica Delphi , Humanos , Doença Pulmonar Obstrutiva Crônica/terapia , Projetos de Pesquisa , Resultado do Tratamento
20.
Eur Respir J ; 60(2)2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35086829

RESUMO

The Human Cell Atlas (HCA) consortium aims to establish an atlas of all organs in the healthy human body at single-cell resolution to increase our understanding of basic biological processes that govern development, physiology and anatomy, and to accelerate diagnosis and treatment of disease. The Lung Biological Network of the HCA aims to generate the Human Lung Cell Atlas as a reference for the cellular repertoire, molecular cell states and phenotypes, and cell-cell interactions that characterise normal lung homeostasis in healthy lung tissue. Such a reference atlas of the healthy human lung will facilitate mapping the changes in the cellular landscape in disease. The discovAIR project is one of six pilot actions for the HCA funded by the European Commission in the context of the H2020 framework programme. discovAIR aims to establish the first draft of an integrated Human Lung Cell Atlas, combining single-cell transcriptional and epigenetic profiling with spatially resolving techniques on matched tissue samples, as well as including a number of chronic and infectious diseases of the lung. The integrated Human Lung Cell Atlas will be available as a resource for the wider respiratory community, including basic and translational scientists, clinical medicine, and the private sector, as well as for patients with lung disease and the interested lay public. We anticipate that the Human Lung Cell Atlas will be the founding stone for a more detailed understanding of the pathogenesis of lung diseases, guiding the design of novel diagnostics and preventive or curative interventions.


Assuntos
Pneumopatias , Pulmão , Humanos , Proteômica , Tórax
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