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1.
Cell ; 184(2): 545-559.e22, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33357446

RESUMO

Biological processes are regulated by intermolecular interactions and chemical modifications that do not affect protein levels, thus escaping detection in classical proteomic screens. We demonstrate here that a global protein structural readout based on limited proteolysis-mass spectrometry (LiP-MS) detects many such functional alterations, simultaneously and in situ, in bacteria undergoing nutrient adaptation and in yeast responding to acute stress. The structural readout, visualized as structural barcodes, captured enzyme activity changes, phosphorylation, protein aggregation, and complex formation, with the resolution of individual regulated functional sites such as binding and active sites. Comparison with prior knowledge, including other 'omics data, showed that LiP-MS detects many known functional alterations within well-studied pathways. It suggested distinct metabolite-protein interactions and enabled identification of a fructose-1,6-bisphosphate-based regulatory mechanism of glucose uptake in E. coli. The structural readout dramatically increases classical proteomics coverage, generates mechanistic hypotheses, and paves the way for in situ structural systems biology.


Assuntos
Proteínas de Escherichia coli/metabolismo , Imageamento Tridimensional , Proteoma/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Regulação Alostérica , Sequência de Aminoácidos , Escherichia coli/enzimologia , Escherichia coli/metabolismo , Espectrometria de Massas , Simulação de Dinâmica Molecular , Pressão Osmótica , Fosforilação , Proteólise , Reprodutibilidade dos Testes , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Estresse Fisiológico
2.
Cell ; 172(1-2): 358-372.e23, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29307493

RESUMO

Metabolite-protein interactions control a variety of cellular processes, thereby playing a major role in maintaining cellular homeostasis. Metabolites comprise the largest fraction of molecules in cells, but our knowledge of the metabolite-protein interactome lags behind our understanding of protein-protein or protein-DNA interactomes. Here, we present a chemoproteomic workflow for the systematic identification of metabolite-protein interactions directly in their native environment. The approach identified a network of known and novel interactions and binding sites in Escherichia coli, and we demonstrated the functional relevance of a number of newly identified interactions. Our data enabled identification of new enzyme-substrate relationships and cases of metabolite-induced remodeling of protein complexes. Our metabolite-protein interactome consists of 1,678 interactions and 7,345 putative binding sites. Our data reveal functional and structural principles of chemical communication, shed light on the prevalence and mechanisms of enzyme promiscuity, and enable extraction of quantitative parameters of metabolite binding on a proteome-wide scale.


Assuntos
Metaboloma , Proteoma/metabolismo , Proteômica/métodos , Transdução de Sinais , Software , Regulação Alostérica , Sítios de Ligação , Escherichia coli , Metabolômica/métodos , Ligação Proteica , Mapas de Interação de Proteínas , Proteoma/química , Saccharomyces cerevisiae , Análise de Sequência de Proteína/métodos
3.
Mol Cell ; 83(18): 3360-3376.e11, 2023 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-37699397

RESUMO

Aging is associated with progressive phenotypic changes. Virtually all cellular phenotypes are produced by proteins, and their structural alterations can lead to age-related diseases. However, we still lack comprehensive knowledge of proteins undergoing structural-functional changes during cellular aging and their contributions to age-related phenotypes. Here, we conducted proteome-wide analysis of early age-related protein structural changes in budding yeast using limited proteolysis-mass spectrometry (LiP-MS). The results, compiled in online ProtAge catalog, unraveled age-related functional changes in regulators of translation, protein folding, and amino acid metabolism. Mechanistically, we found that folded glutamate synthase Glt1 polymerizes into supramolecular self-assemblies during aging, causing breakdown of cellular amino acid homeostasis. Inhibiting Glt1 polymerization by mutating the polymerization interface restored amino acid levels in aged cells, attenuated mitochondrial dysfunction, and led to lifespan extension. Altogether, this comprehensive map of protein structural changes enables identifying mechanisms of age-related phenotypes and offers opportunities for their reversal.


Assuntos
Senescência Celular , Longevidade , Longevidade/genética , Polimerização , Aminoácidos
4.
Mol Syst Biol ; 20(6): 651-675, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38702390

RESUMO

The physical interactome of a protein can be altered upon perturbation, modulating cell physiology and contributing to disease. Identifying interactome differences of normal and disease states of proteins could help understand disease mechanisms, but current methods do not pinpoint structure-specific PPIs and interaction interfaces proteome-wide. We used limited proteolysis-mass spectrometry (LiP-MS) to screen for structure-specific PPIs by probing for protease susceptibility changes of proteins in cellular extracts upon treatment with specific structural states of a protein. We first demonstrated that LiP-MS detects well-characterized PPIs, including antibody-target protein interactions and interactions with membrane proteins, and that it pinpoints interfaces, including epitopes. We then applied the approach to study conformation-specific interactors of the Parkinson's disease hallmark protein alpha-synuclein (aSyn). We identified known interactors of aSyn monomer and amyloid fibrils and provide a resource of novel putative conformation-specific aSyn interactors for validation in further studies. We also used our approach on GDP- and GTP-bound forms of two Rab GTPases, showing detection of differential candidate interactors of conformationally similar proteins. This approach is applicable to screen for structure-specific interactomes of any protein, including posttranslationally modified and unmodified, or metabolite-bound and unbound protein states.


Assuntos
alfa-Sinucleína , Humanos , alfa-Sinucleína/metabolismo , alfa-Sinucleína/química , Mapeamento de Interação de Proteínas , Espectrometria de Massas , Ligação Proteica , Proteólise , Doença de Parkinson/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Mapas de Interação de Proteínas , Conformação Proteica , Amiloide/metabolismo , Amiloide/química , Proteoma/metabolismo
5.
Proc Natl Acad Sci U S A ; 119(2)2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34983869

RESUMO

Precise information on localized variations in blood circulation holds the key for noninvasive diagnostics and therapeutic assessment of various forms of cancer. While thermal imaging by itself may provide significant insights on the combined implications of the relevant physiological parameters, viz. local blood perfusion and metabolic balance due to active tumors as well as the ambient conditions, knowledge of the tissue surface temperature alone may be somewhat inadequate in distinguishing between some ambiguous manifestations of precancer and cancerous lesions, resulting in compromise of the selectivity in detection. This, along with the lack of availability of a user-friendly and inexpensive portable device for thermal-image acquisition, blood perfusion mapping, and data integration acts as a deterrent against the emergence of an inexpensive, contact-free, and accurate in situ screening and diagnostic approach for cancer detection and management. Circumventing these constraints, here we report a portable noninvasive blood perfusion imager augmented with machine learning-based quantitative analytics for screening precancerous and cancerous traits in oral lesions, by probing the localized alterations in microcirculation. With a proven overall sensitivity >96.66% and specificity of 100% as compared to gold-standard biopsy-based tests, the method successfully classified oral cancer and precancer in a resource-limited clinical setting in a double-blinded patient trial and exhibited favorable predictive capabilities considering other complementary modes of medical image analysis as well. The method holds further potential to achieve contrast-free, accurate, and low-cost diagnosis of abnormal microvascular physiology and other clinically vulnerable conditions, when interpreted along with complementary clinically evidenced decision-making perspectives.


Assuntos
Diagnóstico por Imagem/métodos , Programas de Rastreamento/métodos , Neoplasias Bucais/diagnóstico por imagem , Perfusão/métodos , Adulto , Idoso de 80 Anos ou mais , Algoritmos , Biópsia , Diagnóstico por Imagem/instrumentação , Detecção Precoce de Câncer , Humanos , Processamento de Imagem Assistida por Computador , Aprendizado de Máquina , Masculino , Programas de Rastreamento/instrumentação , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Perfusão/instrumentação , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem
6.
Proc Natl Acad Sci U S A ; 119(43): e2207902119, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36252043

RESUMO

Self-assembly is one of the most promising strategies for making functional materials at the nanoscale, yet new design principles for making self-limiting architectures, rather than spatially unlimited periodic lattice structures, are needed. To address this challenge, we explore the tradeoffs between addressable assembly and self-closing assembly of a specific class of self-limiting structures: cylindrical tubules. We make triangular subunits using DNA origami that have specific, valence-limited interactions and designed binding angles, and we study their assembly into tubules that have a self-limited width that is much larger than the size of an individual subunit. In the simplest case, the tubules are assembled from a single component by geometrically programming the dihedral angles between neighboring subunits. We show that the tubules can reach many micrometers in length and that their average width can be prescribed through the dihedral angles. We find that there is a distribution in the width and the chirality of the tubules, which we rationalize by developing a model that considers the finite bending rigidity of the assembled structure as well as the mechanism of self-closure. Finally, we demonstrate that the distributions of tubules can be further sculpted by increasing the number of subunit species, thereby increasing the assembly complexity, and demonstrate that using two subunit species successfully reduces the number of available end states by half. These results help to shed light on the roles of assembly complexity and geometry in self-limited assembly and could be extended to other self-limiting architectures, such as shells, toroids, or triply periodic frameworks.


Assuntos
DNA , Nanoestruturas , Coloides/química , DNA/química , Nanoestruturas/química , Nanotecnologia/métodos , Conformação de Ácido Nucleico
7.
J Proteome Res ; 23(6): 2230-2240, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38690845

RESUMO

Deep proteomic profiling of complex biological and medical samples available at low nanogram and subnanogram levels is still challenging. Thorough optimization of settings, parameters, and conditions in nanoflow liquid chromatography-tandem mass spectrometry (MS)-based proteomic profiling is crucial for generating informative data using amount-limited samples. This study demonstrates that by adjusting selected instrument parameters, e.g., ion injection time, automated gain control, and minimally altering the conditions for resuspending or storing the sample in solvents of different compositions, up to 15-fold more thorough proteomic profiling can be achieved compared to conventionally used settings. More specifically, the analysis of 1 ng of the HeLa protein digest standard by Q Exactive HF-X Hybrid Quadrupole-Orbitrap and Orbitrap Fusion Lumos Tribrid mass spectrometers yielded an increase from 1758 to 5477 (3-fold) and 281 to 4276 (15-fold) peptides, respectively, demonstrating that higher protein identification results can be obtained using the optimized methods. While the instruments applied in this study do not belong to the latest generation of mass spectrometers, they are broadly used worldwide, which makes the guidelines for improving performance desirable to a wide range of proteomics practitioners.


Assuntos
Proteômica , Espectrometria de Massas em Tandem , Proteômica/métodos , Humanos , Espectrometria de Massas em Tandem/métodos , Células HeLa , Cromatografia Líquida/métodos , Proteoma/análise , Peptídeos/análise , Peptídeos/química
8.
J Proteome Res ; 23(6): 2148-2159, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38785273

RESUMO

Diverse proteomics-based strategies have been applied to saliva to quantitatively identify diagnostic and prognostic targets for oral cancer. Considering that these targets may be regulated by events that do not imply variation in protein abundance levels, we hypothesized that changes in protein conformation can be associated with diagnosis and prognosis, revealing biological processes and novel targets of clinical relevance. For this, we employed limited proteolysis-mass spectrometry in saliva samples to explore structural alterations, comparing the proteome of healthy control and oral squamous cell carcinoma (OSCC) patients with and without lymph node metastasis. Thirty-six proteins with potential structural rearrangements were associated with clinical patient features including transketolase and its interacting partners. Moreover, N-glycosylated peptides contribute to structural rearrangements of potential diagnostic and prognostic markers. Altogether, this approach utilizes saliva proteins to search for targets for diagnosing and prognosing oral cancer and can guide the discovery of potential regulated sites beyond protein-level abundance.


Assuntos
Neoplasias Bucais , Proteoma , Saliva , Humanos , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Neoplasias Bucais/diagnóstico , Saliva/química , Saliva/metabolismo , Proteoma/análise , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/diagnóstico , Feminino , Biomarcadores Tumorais/metabolismo , Masculino , Metástase Linfática , Conformação Proteica , Pessoa de Meia-Idade , Prognóstico , Proteômica/métodos , Transcetolase/metabolismo , Idoso , Espectrometria de Massas , Proteínas e Peptídeos Salivares/metabolismo , Proteínas e Peptídeos Salivares/análise
9.
J Proteome Res ; 23(7): 2332-2342, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38787630

RESUMO

Here, we present FLiPPR, or FragPipe LiP (limited proteolysis) Processor, a tool that facilitates the analysis of data from limited proteolysis mass spectrometry (LiP-MS) experiments following primary search and quantification in FragPipe. LiP-MS has emerged as a method that can provide proteome-wide information on protein structure and has been applied to a range of biological and biophysical questions. Although LiP-MS can be carried out with standard laboratory reagents and mass spectrometers, analyzing the data can be slow and poses unique challenges compared to typical quantitative proteomics workflows. To address this, we leverage FragPipe and then process its output in FLiPPR. FLiPPR formalizes a specific data imputation heuristic that carefully uses missing data in LiP-MS experiments to report on the most significant structural changes. Moreover, FLiPPR introduces a data merging scheme and a protein-centric multiple hypothesis correction scheme, enabling processed LiP-MS data sets to be more robust and less redundant. These improvements strengthen statistical trends when previously published data are reanalyzed with the FragPipe/FLiPPR workflow. We hope that FLiPPR will lower the barrier for more users to adopt LiP-MS, standardize statistical procedures for LiP-MS data analysis, and systematize output to facilitate eventual larger-scale integration of LiP-MS data.


Assuntos
Espectrometria de Massas , Proteólise , Proteômica , Proteômica/métodos , Espectrometria de Massas/métodos , Software , Proteoma/análise , Fluxo de Trabalho , Humanos
10.
Neuroimage ; 288: 120528, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38311125

RESUMO

Quantitative susceptibility mapping (QSM) is frequently employed in investigating brain iron related to brain development and diseases within deep gray matter (DGM). Nonetheless, the acquisition of whole-brain QSM data is time-intensive. An alternative approach, focusing the QSM specifically on areas of interest such as the DGM by reducing the field-of-view (FOV), can significantly decrease scan times. However, severe susceptibility value underestimations have been reported during QSM reconstruction with a limited FOV, largely attributable to artifacts from incorrect background field removal in the boundary region. This presents a considerable barrier to the clinical use of QSM with small spatial coverages using conventional methods alone. To mitigate the propagation of these errors, we proposed a harmonic field extension method based on a physics-informed generative adversarial network. Both quantitative and qualitative results demonstrate that our method outperforms conventional methods and delivers results comparable to those obtained with full FOV. Furthermore, we demonstrate the versatility of our method by applying it to data acquired prospectively with limited FOV and to data from patients with Parkinson's disease. The method has shown significant improvements in local field results, with QSM outcomes. In a clear illustration of its feasibility and effectiveness in real clinical environments, our proposed method addresses the prevalent issue of susceptibility underestimation in QSM with small spatial coverage.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Algoritmos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos
11.
Cancer ; 130(14): 2515-2527, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38511395

RESUMO

BACKGROUND: Many patients with early-stage lung cancer are not candidates for lobectomy because of various factors, with treatment options including sublobar resection or stereotactic body radiation therapy (SBRT). Limited information exists regarding patient-centered outcomes after these treatments. METHODS: Subjects with stage I-IIA non-small cell lung cancer (NSCLC) at high risk for lobectomy who underwent treatment with sublobar resection or SBRT were recruited from five medical centers. Quality of life (QOL) was compared with the Short Form 8 (SF-8) for physical and mental health and Functional Assessment of Cancer Therapy-Lung (FACT-L) surveys at baseline (pretreatment) and 7 days, 30 days, 6 months, and 12 months after treatment. Propensity score methods were used to control for confounders. RESULTS: Of 337 subjects enrolled before treatment, 63% received SBRT. Among patients undergoing resection, 89% underwent minimally invasive video-assisted thoracic surgery or robot-assisted resection. Adjusted analyses showed that SBRT-treated patients had both higher physical health SF-8 scores (difference in differences [DID], 6.42; p = .0008) and FACT-L scores (DID, 2.47; p = .004) at 7 days posttreatment. Mental health SF-8 scores were not different at 7 days (p = .06). There were no significant differences in QOL at other time points, and all QOL scores returned to baseline by 12 months for both groups. CONCLUSIONS: SBRT is associated with better QOL immediately posttreatment compared with sublobar resection. However, both treatment groups reported similar QOL at later time points, with a return to baseline QOL. These findings suggest that sublobar resection and SBRT have a similar impact on the QOL of patients with early-stage lung cancer deemed ineligible for lobectomy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Pneumonectomia , Qualidade de Vida , Radiocirurgia , Humanos , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/psicologia , Radiocirurgia/métodos , Masculino , Feminino , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/psicologia , Idoso , Pessoa de Meia-Idade , Pneumonectomia/métodos , Estadiamento de Neoplasias , Estudos Longitudinais , Resultado do Tratamento , Idoso de 80 Anos ou mais , Cirurgia Torácica Vídeoassistida/métodos
12.
Eur J Neurosci ; 59(7): 1681-1695, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38311832

RESUMO

African science has substantial potential, yet it grapples with significant challenges. Here we describe the establishment of the Biomedical Science Research and Training Centre (BioRTC) in Yobe State, Northeast Nigeria, as a case study of a hub fostering on-continent research and describe strategies to overcome current barriers. We detail the steps taken to establish BioRTC, emphasising the critical importance of stakeholder engagement, community involvement, resource optimisation and collaborations. With its state-of-the-art facilities and commitment to training African scientists, BioRTC is poised to significantly advance neuroscience research and training in the region. Although we are in the early stages of our journey, our model, emphasizing open access and inclusivity, offers a replicable blueprint for neuroscience research development in similar resource-limited settings, promising to enrich the global neuroscience community. We invite the support and collaboration of those who share our vision and believe in our potential.


Assuntos
Pesquisa Biomédica , Neurociências , Nigéria , Neurociências/educação
13.
Am Nat ; 203(1): E19-E34, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38207145

RESUMO

AbstractIn patch- or habitat-structured populations, different processes can favor adaptive polymorphism at different scales. While spatial heterogeneity can generate spatially disruptive selection favoring variation between patches, local competition can lead to locally disruptive selection promoting variation within patches. So far, almost all theory has studied these two processes in isolation. Here, we use mathematical modeling to investigate how resource variation within and between habitats influences the evolution of variation in a consumer population where individuals compete in finite patches connected by dispersal. We find that locally and spatially disruptive selection typically act in concert, favoring polymorphism under a wider range of conditions than when in isolation. But when patches are small and dispersal between them is low, kin competition inhibits the emergence of polymorphism, especially when the latter is driven by local competition for resources. We further use our model to clarify what comparisons between trait and neutral genetic differentiation (QST/FST comparisons) can tell about the nature of selection. Overall, our results help us understand the interaction between two major drivers of polymorphism: locally and spatially disruptive selection, and how this interaction is modulated by the unavoidable effects of kin selection under limited dispersal.


Assuntos
Ecossistema , Modelos Teóricos , Humanos , Dinâmica Populacional , Deriva Genética , Polimorfismo Genético , Evolução Biológica , Seleção Genética
14.
Artigo em Inglês | MEDLINE | ID: mdl-38906441

RESUMO

BACKGROUND AND AIMS: Despite the poor prognosis associated with missed or delayed spontaneous bacterial peritonitis (SBP) diagnosis, <15% get timely paracentesis, which persists despite guidelines/education in the US. Measures to exclude SBP non-invasively where timely paracentesis cannot be performed could streamline this burden. METHODS: Using Veterans Health Administration Corporate Data Warehouse (VHA-CDW) we included cirrhosis patients between 2009-2019 who underwent timely paracentesis and collected relevant clinical information (demographics, cirrhosis severity, medications, vitals, and comorbidities). XGBoost-models were trained on 75% of the primary cohort, with 25% reserved for testing. The final model was further validated in two cohorts: Validation cohort #1: In VHA-CDW, those without prior SBP who received 2nd early paracentesis, and Validation cohort #2: Prospective data from 276 non-electively admitted University hospital patients. RESULTS: Negative predictive values (NPV) at 5,10 & 15% probability cutoffs were examined. Primary cohort: n=9,643 (mean age 63.1±8.7 years, 97.2% men, SBP:15.0%) received first early paracentesis. Testing-set NPVs for SBP were 96.5%, 93.0% and 91.6% at the 5%, 10% and 15% probability thresholds respectively. In Validation cohort #1: n=2844 (mean age 63.14±8.37 years, 97.1% male, SBP: 9.7%) with NPVs were 98.8%, 95.3% and 94.5%. In Validation cohort #2: n=276 (mean age 56.08±9.09, 59.6% male, SBP: 7.6%) with NPVs were 100%, 98.9% and 98.0% The final ML model showed the greatest net benefit on decision-curve analyses. CONCLUSIONS: A machine learning model generated using routinely collected variables excluded SBP with high negative predictive value. Applying this model could ease the need to provide paracentesis in resource-limited settings by excluding those unlikely to have SBP.

15.
Biochem Biophys Res Commun ; 696: 149488, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38219485

RESUMO

Enzymatic methyl-seq (EM-seq), an enzyme-based method, identifies genome-wide DNA methylation, which enables us to obtain reliable methylome data from purified genomic DNA by avoiding bisulfite-induced DNA damage. However, the loss of DNA during purification hinders the methylome analysis of limited samples. The crude DNA extraction method is the quickest and minimal sample loss approach for obtaining useable DNA without requiring additional dissolution and purification. However, it remains unclear whether crude DNA can be used directly for EM-seq library construction. In this study, we aimed to assess the quality of EM-seq libraries prepared directly using crude DNA. The crude DNA-derived libraries provided appropriate fragment sizes and concentrations for sequencing similar to those of the purified DNA-derived libraries. However, the sequencing results of crude samples exhibited lower reference sequence mapping efficiencies than those of the purified samples. Additionally, the lower-input crude DNA-derived sample exhibited a marginally lower cytosine-to-thymine conversion efficiency and hypermethylated pattern around gene regulatory elements than the higher-input crude DNA- or purified DNA-derived samples. In contrast, the methylation profiles of the crude and purified samples exhibited a significant correlation. Our findings indicate that crude DNA can be used as a raw material for EM-seq library construction.


Assuntos
Metilação de DNA , DNA , Biblioteca Gênica , Sequência de Bases , DNA/genética , DNA/análise , Clonagem Molecular , Análise de Sequência de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Sulfitos
16.
Expert Rev Mol Med ; 26: e6, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38604802

RESUMO

Target deconvolution can help understand how compounds exert therapeutic effects and can accelerate drug discovery by helping optimise safety and efficacy, revealing mechanisms of action, anticipate off-target effects and identifying opportunities for therapeutic expansion. Chemoproteomics, a combination of chemical biology with mass spectrometry has transformed target deconvolution. This review discusses modification-free chemoproteomic approaches that leverage the change in protein thermodynamics induced by small molecule ligand binding. Unlike modification-based methods relying on enriching specific protein targets, these approaches offer proteome-wide evaluations, driven by advancements in mass spectrometry sensitivity, increasing proteome coverage and quantitation methods. Advances in methods based on denaturation/precipitation by thermal or chemical denaturation, or by protease degradation are evaluated, emphasising the evolving landscape of chemoproteomics and its potential impact on future drug-development strategies.


Assuntos
Descoberta de Drogas , Proteoma , Humanos , Proteoma/análise , Proteoma/química , Proteoma/metabolismo , Descoberta de Drogas/métodos , Espectrometria de Massas , Desenvolvimento de Medicamentos
17.
Small ; : e2311543, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38334249

RESUMO

Dendrites are ubiquitous crystals produced in supersaturated solutions and supercooled melts, but considerably less is known about their formation and growth kinetics. Here, the key factors are explored that dictate dendrite formation and growth, utilizing experimental colloidal models in which the particles act as molecules with Mie potential. Depletion attraction is employed to colloids and manipulate their strength to control supersaturation. Dendrites are predominantly produced under conditions of low supersaturation, where the separation between crystals is large due to slow nucleation. The dendrites do not emerge directly from nuclei. Instead, isotropic grains, initially produced from nuclei, morph into polygons. Arms then sprout from the vertices of these polygons, eventually giving rise to dendrites. Triggering this polygon-to-dendrite transformation requires a high diffusional flux. This necessitates a prolonged diffusion time to maintain a steep concentration gradient in the surrounding environment even after the transformation from circular grains to polygons.

18.
HIV Med ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689512

RESUMO

OBJECTIVES: Our aim was to determine the prevalence and characteristics of people with HIV on antiretroviral therapy (ART) with multidrug resistance (MDR; confirmed resistance to three or more [or resistance to two or more plus contraindication to one or more] core ART classes) and limited treatment options (LTOs) in Spain. METHODS: This was an observational, retrospective, multicentre, cross-sectional chart review study undertaken in five reference Spanish centres. Participants were people with HIV on ART with MDR and LTOs (detectable viral load [HIV-RNA >200 copies/mL], treatment-limiting drug-drug interaction [DDI], or intolerance precluding the use of one or more ART classes). Prevalence, demographic/clinical characteristics, and treatment options were assessed. Logistic regression analyses were used to identify MDR-associated variables. RESULTS: Of 14 955 screened people with HIV, 69 (0.46%) presented with MDR and 23 (0.15%) had LTOs. The population analysed was 73.9% male with a median age of 54.0 years; the median time since HIV diagnosis was 26.5 years, and median CD4+ cell count was 511.0 cells/µL. The only factor significantly associated with MDR (univariate analysis) was CD4+ cell count. Injection drug use was the most common transmission route. Comorbidities (mainly endocrine and cardiovascular disorders; 34.8% affecting HIV management) and concomitant treatments were frequent. No recent opportunistic infections were reported. Patients had been exposed to the following ART: nucleoside analogue reverse transcriptase inhibitors (100%), protease inhibitors (95.6%), non-nucleoside analogue reverse transcriptase inhibitors (87.0%), and integrase strand transfer inhibitors (82.6%). The available fully active drugs were dolutegravir (39.1%), bictegravir (30.4%), and raltegravir (21.7%). CONCLUSIONS: The prevalence of people with HIV with MDR and LTOs in Spain is very low, with approximately half of those studied not exhibiting virological suppression. Low CD4+ cell counts were associated with MDR. These findings may help address the impact and treatment needs of these patients and prevent clinical progression and transmission of MDR HIV.

19.
J Autoimmun ; 147: 103265, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38838452

RESUMO

OBJECTIVES: The aim of the study was to establish an international multicenter registry to collect data on patients with Multisystem Inflammatory Syndrome in Children (MIS-C), in order to highlight a relationship between clinical presentation, age of onset and geographical distribution on the clinical outcome. STUDY DESIGN: Multicenter retrospective study involving different international societies for rare immunological disorders.1009 patients diagnosed with MIS-C between March and September 2022, from 48 centers and 22 countries were collected. Five age groups (<1, 1-4, 5-11, 12-16, >16 years) and four geographic macro-areas, Western Europe, Central-Eastern Europe, Latin America, Asian-African resource-limited countries (LRC), were identified. RESULTS: Time to referral was significantly higher in LRC. Intensive anti-inflammatory treatment, including biologics, respiratory support and mechanic ventilation were more frequently used in older children and in European countries. The mortality rate was higher in very young children (<1 year), in older patients (>16 years of age) and in LRC. Multivariate analysis identified the residence in LRC, presence of severe cardiac involvement, renal hypertension, lymphopenia and non-use of heparin prophylaxis, as the factors most strongly associated with unfavorable outcomes. CONCLUSIONS: The stratification of patients by age and geographic macro-area provided insights into the clinical presentation, treatment and outcome of MIS-C. The mortality and sequelae rates exhibited a correlation with the age and geographical areas. Patients admitted and treated in LRC displayed more severe outcomes, possibly due to delays in hospital admission and limited access to biologic drugs and to intensive care facilities.

20.
Ann Surg Oncol ; 31(2): 1243-1251, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37947973

RESUMO

BACKGROUND: Limited anatomic resections (LARs), such as segmentectomies, performed using a fully laparoscopic approach, have gained popularity for liver malignancies. However, the oncologic efficacy of laparoscopic LARs (Lap-LARs) needs further investigation. This cohort study evaluated the oncologic outcomes of Lap-LAR for hepatocellular carcinoma (HCC) and colorectal liver metastasis (CRLM). METHODS: At a Japanese referral center, 112 patients underwent Lap-LAR using the Glissonean approach and indocyanine green (ICG) fluorescence navigation. Recurrence-free survival (RFS), overall survival (OS), time to interventional failure (TIF), and time to surgical failure (TSF) were assessed. RESULTS: Among the 112 patients (median age, 74 years [range, 66-80 years]; 80 men [71.4 %]), Lap-LAR showed promising results. The median operative time was 348 min (range, 280-460 min), and the median blood loss was 190 mL (range, 95.5-452.0 mL). The median error between the estimated and actual liver volumes was 2 % (1.2-4.8 %). Complications greater than Clavien-Dindo 3a were observed in 11.6 % of the patients. The 5-year RFS, OS, and TIF rates for HCC were 45.1 % ± 7.9 %, 73.1 % ± 6.7 %, and 74.2 % ± 6 .6 %, respectively. The 5-year RFS, OS, and TSF rates for CRLM were 36.8 % ± 8.7 %, 60.1 % ± 13.3 %, and 63.6 % ± 10.4 %, respectively. CONCLUSIONS: Lap-LAR showed favorable oncologic outcomes for HCC and CRLM. Its precise technique makes it a promising therapeutic option for liver malignancies. Further comparisons with conventional approaches are warranted.


Assuntos
Carcinoma Hepatocelular , Laparoscopia , Neoplasias Hepáticas , Masculino , Humanos , Idoso , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/secundário , Estudos de Coortes , Hepatectomia/métodos , Laparoscopia/métodos , Estudos Retrospectivos
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