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1.
BMJ Ment Health ; 27(1)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580438

RESUMO

BACKGROUND: Mental health disorders (MHDs) are associated with physical health disparities, but underlying excess risk and health burden have not yet been comprehensively assessed. OBJECTIVE: To assess the burden of comorbid physical health conditions (PHCs) across serious MHDs in Europe. METHODS: We estimated the relative prevalence risk of PHCs associated with alcohol use disorders (AUD), bipolar disorder (BD), depressive disorders (DD) and schizophrenia (SZ) across working-age populations of 32 European countries in 2019 based on a targeted literature review. Excess physical health burden was modelled using population-attributable fractions and country-level prevalence data. FINDINGS: We screened 10 960 studies, of which 41 were deemed eligible, with a total sample size of over 18 million persons. Relative prevalence of PHCs was reported in 54%, 20%, 15%, 5% and 7% of studies, respectively, for SZ, DD, BD, AUD or mixed. Significant relative risk estimates ranged from 1.44 to 3.66 for BD, from 1.43 to 2.21 for DD, from 0.81 to 1.97 for SZ and 3.31 for AUD. Excess physical health burden ranged between 27% and 67% of the total, corresponding to 84 million (AUD), 67 million (BD), 66 million (DD) and 5 million (SZ) PHC diagnoses in Europe. A 1% reduction in excess risk assuming causal inference could result in two million fewer PHCs across investigated MHDs. CONCLUSIONS: This is the first comprehensive study of the physical health burden of serious MHDs in Europe. The methods allow for updates, refinement and extension to other MHDs or geographical areas. CLINICAL IMPLICATIONS: The results indicate potential population health benefits achievable through more integrated mental and physical healthcare and prevention approaches.


Assuntos
Alcoolismo , Transtorno Bipolar , Esquizofrenia , Humanos , Alcoolismo/complicações , Saúde Mental , Transtorno Bipolar/epidemiologia , Esquizofrenia/epidemiologia , Europa (Continente)/epidemiologia
2.
Front Mol Biosci ; 9: 942406, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36213120

RESUMO

The primary aim of the study was to identify inflammatory markers relevant for osteoarthritis (OA)-related systemic (plasma) and local (synovial fluid, SF) inflammation. From this, we looked for inflammatory markers that coincided with the increased amount of O-linked Tn antigen (GalNAcα1-Ser/Thr) glycan on SF lubricin. Inflammatory markers in plasma and SF in OA patients and controls were measured using a 44-multiplex immunoassay. We found consistently 29 markers detected in both plasma and SF. The difference in their concentration and the low correlation when comparing SF and plasma suggests an independent inflammatory environment in the two biofluids. Only plasma MCP-4 and TARC increased in our patient cohort compared to control plasma. To address the second task, we concluded that plasma markers were irrelevant for a direct connection with SF glycosylation. Hence, we correlated the SF-inflammatory marker concentrations with the level of altered glycosylation of SF-lubricin. We found that the level of SF-IL-8 and SF-MIP-1α and SF-VEGFA in OA patients displayed a positive correlation with the altered lubricin glycosylation. Furthermore, when exposing fibroblast-like synoviocytes from both controls and OA patients to glycovariants of recombinant lubricin, the secretion of IL-8 and MIP-1α and VEGFA were elevated using lubricin with Tn antigens, while lubricin with sialylated and nonsialylated T antigens had less or no measurable effect. These data suggest that truncated glycans of lubricin, as found in OA, promote synovial proinflammatory cytokine production and exacerbate local synovial inflammation.

4.
Nat Commun ; 13(1): 3579, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-35739101

RESUMO

The international community has committed to achieve 169 Sustainable Development Goal (SDG) targets by 2030 and to enhance climate adaptation under the Paris Agreement. Despite the potential for synergies, aligning SDG and climate adaptation efforts is inhibited by an inadequate understanding of the complex relationship between SDG targets and adaptation to impacts of climate change. Here we propose a framework to conceptualise how ecosystems and socio-economic sectors mediate this relationship, which provides a more nuanced understanding of the impacts of climate change on all 169 SDG targets. Global application of the framework reveals that adaptation of wetlands, rivers, cropland, construction, water, electricity, and housing in the most vulnerable countries is required to safeguard achievement of 68% of SDG targets from near-term climate risk by 2030. We discuss how our framework can help align National Adaptation Plans with SDG targets, thus ensuring that adaptation advances, rather than detracts from, sustainable development.


Assuntos
Ecossistema , Desenvolvimento Sustentável , Aclimatação , Mudança Climática , Objetivos , Paris
5.
Ann Rheum Dis ; 81(8): 1085-1095, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35470158

RESUMO

OBJECTIVES: To find causal genes for rheumatoid arthritis (RA) and its seropositive (RF and/or ACPA positive) and seronegative subsets. METHODS: We performed a genome-wide association study (GWAS) of 31 313 RA cases (68% seropositive) and ~1 million controls from Northwestern Europe. We searched for causal genes outside the HLA-locus through effect on coding, mRNA expression in several tissues and/or levels of plasma proteins (SomaScan) and did network analysis (Qiagen). RESULTS: We found 25 sequence variants for RA overall, 33 for seropositive and 2 for seronegative RA, altogether 37 sequence variants at 34 non-HLA loci, of which 15 are novel. Genomic, transcriptomic and proteomic analysis of these yielded 25 causal genes in seropositive RA and additional two overall. Most encode proteins in the network of interferon-alpha/beta and IL-12/23 that signal through the JAK/STAT-pathway. Highlighting those with largest effect on seropositive RA, a rare missense variant in STAT4 (rs140675301-A) that is independent of reported non-coding STAT4-variants, increases the risk of seropositive RA 2.27-fold (p=2.1×10-9), more than the rs2476601-A missense variant in PTPN22 (OR=1.59, p=1.3×10-160). STAT4 rs140675301-A replaces hydrophilic glutamic acid with hydrophobic valine (Glu128Val) in a conserved, surface-exposed loop. A stop-mutation (rs76428106-C) in FLT3 increases seropositive RA risk (OR=1.35, p=6.6×10-11). Independent missense variants in TYK2 (rs34536443-C, rs12720356-C, rs35018800-A, latter two novel) associate with decreased risk of seropositive RA (ORs=0.63-0.87, p=10-9-10-27) and decreased plasma levels of interferon-alpha/beta receptor 1 that signals through TYK2/JAK1/STAT4. CONCLUSION: Sequence variants pointing to causal genes in the JAK/STAT pathway have largest effect on seropositive RA, while associations with seronegative RA remain scarce.


Assuntos
Artrite Reumatoide , Estudo de Associação Genômica Ampla , Artrite Reumatoide/genética , Predisposição Genética para Doença/genética , Humanos , Interferon-alfa , Janus Quinases/genética , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Proteômica , Fatores de Transcrição STAT/genética , Transdução de Sinais/genética
6.
Biol Chem ; 403(8-9): 705-715, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35025187

RESUMO

Self-cleaving ribozymes are catalytic RNAs and can be found in all domains of life. They catalyze a site-specific cleavage that results in a 5' fragment with a 2',3' cyclic phosphate (2',3' cP) and a 3' fragment with a 5' hydroxyl (5' OH) end. Recently, several strategies to enrich self-cleaving ribozymes by targeted biochemical methods have been introduced by us and others. Here, we develop an alternative strategy in which 5' OH RNAs are specifically ligated by RtcB ligase, which first guanylates the 3' phosphate of the adapter and then ligates it directly to RNAs with 5' OH ends. Our results demonstrate that adapter ligation to highly structured ribozyme fragments is much more efficient using the thermostable RtcB ligase from Pyrococcus horikoshii than the broadly applied Escherichia coli enzyme. Moreover, we investigated DNA, RNA and modified RNA adapters for their suitability in RtcB ligation reactions. We used the optimized RtcB-mediated ligation to produce RNA-seq libraries and captured a spiked 3' twister ribozyme fragment from E. coli total RNA. This RNA-seq-based method is applicable to detect ribozyme fragments as well as other cellular RNAs with 5' OH termini from total RNA.


Assuntos
Aminoacil-tRNA Sintetases , Proteínas de Escherichia coli , RNA Catalítico , Aminoacil-tRNA Sintetases/química , Aminoacil-tRNA Sintetases/genética , Aminoacil-tRNA Sintetases/metabolismo , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Ligases/genética , Fosfatos/metabolismo , RNA/metabolismo , Splicing de RNA , RNA Catalítico/genética , RNA-Seq
7.
J Bone Miner Res ; 36(10): 2039-2052, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34155688

RESUMO

In hypertrophic chondrocytes, ß-catenin has two roles. First, it locally suppresses the differentiation of osteoclasts at the chondro-osseous junction by maintaining the pro-osteoclastic factor receptor activator of NF-κB ligand (RANKL) at low levels. Second, it promotes the differentiation of osteoblast-precursors from chondrocytes. Yet, ß-catenin is a dual-function protein, which can either participate in cell-cell adherens junctions or serve as a transcriptional co-activator in canonical Wnt signaling interacting with T-cell factor/lymphoid enhancer-binding factor (TCF/LEF) transcription factors. Hence, whenever studying tissue-specific requirements of ß-catenin using a conventional conditional knockout approach, the functional mechanisms underlying the defects in the conditional mutants remain ambiguous. To decipher mechanistically which of the two molecular functions of ß-catenin is required in hypertrophic chondrocytes, we used different approaches. We analyzed the long bones of newborn mice carrying either the null-alleles of Lef1 or Tcf7, or mice in which Tcf7l2 was conditionally deleted in the hypertrophic chondrocytes, as well as double mutants for Lef1 and Tcf7l2, and Tcf7 and Tcf7l2. Furthermore, we analyzed Ctnnb1 mutant newborns expressing a signaling-defective allele that retains the cell adhesion function in hypertrophic chondrocytes. None of the analyzed Tcf/Lef single or double mutants recapitulated the previously published phenotype upon loss of ß-catenin in hypertrophic chondrocytes. However, using this particular Ctnnb1 allele, maintaining cell adhesion function, we show that it is the co-transcriptional activity of ß-catenin, which is required in hypertrophic chondrocytes to suppress osteoclastogenesis and to promote chondrocyte-derived osteoblast differentiation. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).


Assuntos
Condrócitos , beta Catenina , Animais , Diferenciação Celular , Condrócitos/metabolismo , Camundongos , Osteoclastos/metabolismo , Fatores de Transcrição TCF , Via de Sinalização Wnt , beta Catenina/genética , beta Catenina/metabolismo
8.
Cell Death Dis ; 12(5): 494, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33990546

RESUMO

Agonists and antagonists of the canonical Wnt signaling pathway are modulators of pathological aspects of rheumatoid arthritis (RA). Their activity is primarily modifying bone loss and bone formation, as shown in animal models of RA. More recently, modulation of Wnt signaling by the antagonist Sclerostin has also been shown to influence soft-tissue-associated inflammatory aspects of the disease pointing towards a role of Wnt signaling in soft-tissue inflammation as well. Yet, nothing is known experimentally about the role of Wnt ligands in RA. Here we provide evidence that altering Wnt signaling at the level of a ligand affects all aspects of the rheumatoid arthritic disease. WNT9a levels are increased in the pannus tissue of RA patients, and stimulation of synovial fibroblasts (SFB) with tumor necrosis factor (TNF) leads to increased transcription of Wnt9a. Loss of Wnt9a in a chronic TNF-dependent RA mouse model results in an aggravation of disease progression with enhanced pannus formation and joint destruction. Yet, loss of its activity in the acute K/BxN serum-transfer induced arthritis (STIA) mouse model, which is independent of TNF signaling, has no effect on disease severity or progression. Thus, suggesting a specific role for WNT9a in TNF-triggered RA. In synovial fibroblasts, WNT9a can activate the canonical Wnt/ß-catenin pathway, but it can also activate P38- and downregulate NFκB signaling. Based on in vitro data, we propose that loss of Wnt9a creates a slight proinflammatory and procatabolic environment that boosts the TNF-mediated inflammatory response.


Assuntos
Artrite Reumatoide/metabolismo , Proteínas Wnt/metabolismo , Animais , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Camundongos Transgênicos
10.
iScience ; 24(1): 101895, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33364584

RESUMO

Single-molecule localization microscopy (SMLM) reports on protein organization in cells with near-molecular resolution and in combination with stoichiometric labeling enables protein counting. Fluorescent proteins allow stoichiometric labeling of cellular proteins; however, most methods either lead to overexpression or are complex and time demanding. We introduce CRISPR/Cas12a for simple and efficient tagging of endogenous proteins with a photoactivatable protein for quantitative SMLM and single-particle tracking. We constructed a HEK293T cell line with the receptor tyrosine kinase MET tagged with mEos4b and demonstrate full functionality. We determine the oligomeric state of MET with quantitative SMLM and find a reorganization from monomeric to dimeric MET upon ligand stimulation. In addition, we measured the mobility of single MET receptors in vivo in resting and ligand-treated cells. The combination of CRISPR/Cas12a-assisted endogenous protein labeling and super-resolution microscopy represents a powerful tool for cell biological research with molecular resolution.

11.
Methods ; 193: 38-45, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-32389748

RESUMO

Fibroblast growth factor receptors (FGFRs) are a subfamily of receptor tyrosine kinases and central players in health and disease. Following ligand binding and the formation of homo- and heteromeric complexes, FGFRs initiate a cellular response. Challenges in studying FGFR activation are inner-subfamily interactions and a complex heterogeneity of these in the cell membrane, which demand for observation techniques that can resolve individual protein complexes and that are compatible with endogenous protein levels. Here, we established an imaging and analysis pipeline for multiplexed single-molecule localization microscopy (SMLM) of the FGFR network at the plasma membrane. Using DNA-labeled primary antibodies, we visualize all four FGFRs in the same cell with near-molecular spatial resolution. From the super-resolution imaging data, we extract information on FGFR density, spatial distribution, and inner-subfamily colocalization. Our approach is straightforward and easily adaptable to other multiplexed SMLM data of membrane proteins.


Assuntos
Membrana Celular , Microscopia , DNA , Receptores Proteína Tirosina Quinases , Receptores de Fatores de Crescimento de Fibroblastos/genética
12.
Cell Genom ; 1(2)2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-35072136

RESUMO

The Global Alliance for Genomics and Health (GA4GH) aims to accelerate biomedical advances by enabling the responsible sharing of clinical and genomic data through both harmonized data aggregation and federated approaches. The decreasing cost of genomic sequencing (along with other genome-wide molecular assays) and increasing evidence of its clinical utility will soon drive the generation of sequence data from tens of millions of humans, with increasing levels of diversity. In this perspective, we present the GA4GH strategies for addressing the major challenges of this data revolution. We describe the GA4GH organization, which is fueled by the development efforts of eight Work Streams and informed by the needs of 24 Driver Projects and other key stakeholders. We present the GA4GH suite of secure, interoperable technical standards and policy frameworks and review the current status of standards, their relevance to key domains of research and clinical care, and future plans of GA4GH. Broad international participation in building, adopting, and deploying GA4GH standards and frameworks will catalyze an unprecedented effort in data sharing that will be critical to advancing genomic medicine and ensuring that all populations can access its benefits.

13.
Phys Med ; 80: 101-110, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33137621

RESUMO

PURPOSE: To identify intra-lesion imaging heterogeneity biomarkers in multi-parametric Magnetic Resonance Imaging (mpMRI) for breast lesion diagnosis. METHODS: Dynamic Contrast Enhanced (DCE) and Diffusion Weighted Imaging (DWI) of 73 female patients, with 85 histologically verified breast lesions were acquired. Non-rigid multi-resolution registration was utilized to spatially align sequences. Four (4) DCE (2nd post-contrast frame, Initial-Enhancement, Post-Initial-Enhancement and Signal-Enhancement-Ratio) and one (1) DWI (Apparent-Diffusion-Coefficient) representations were analyzed, considering a representative lesion slice. 11 1st-order-statistics and 16 texture features (Gray-Level-Co-occurrence-Matrix (GLCM) and Gray-Level-Run-Length-Matrix (GLRLM) based) were derived from lesion segments, provided by Fuzzy C-Means segmentation, across the 5 representations, resulting in 135 features. Least-Absolute-Shrinkage and Selection-Operator (LASSO) regression was utilized to select optimal feature subsets, subsequently fed into 3 classification schemes: Logistic-Regression (LR), Random-Forest (RF), Support-Vector-Machine-Sequential-Minimal-Optimization (SVM-SMO), assessed with Receiver-Operating-Characteristic (ROC) analysis. RESULTS: LASSO regression resulted in 7, 6 and 7 features subsets from DCE, DWI and mpMRI, respectively. Best classification performance was obtained by the RF multi-parametric scheme (Area-Under-ROC-Curve, (AUC) ± Standard-Error (SE), AUC ± SE = 0.984 ± 0.025), as compared to DCE (AUC ± SE = 0.961 ± 0.030) and DWI (AUC ± SE = 0.938 ± 0.032) and statistically significantly higher as compared to DWI. The selected mpMRI feature subset highlights the significance of entropy (1st-order-statistics and 2nd-order-statistics (GLCM)) and percentile features extracted from 2nd post-contrast frame, PIE, SER maps and ADC map. CONCLUSION: Capturing breast intra-lesion heterogeneity, across mpMRI lesion segments with 1st-order-statistics and texture features (GLCM and GLRLM based), offers a valuable diagnostic tool for breast cancer.


Assuntos
Neoplasias da Mama , Imageamento por Ressonância Magnética Multiparamétrica , Biomarcadores , Neoplasias da Mama/diagnóstico por imagem , Meios de Contraste , Feminino , Humanos , Imageamento por Ressonância Magnética
14.
J Biol Chem ; 295(47): 16023-16036, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-32928962

RESUMO

The synovial fluid glycoprotein lubricin (also known as proteoglycan 4) is a mucin-type O-linked glycosylated biological lubricant implicated to be involved in osteoarthritis (OA) development. Lubricin's ability to reduce friction is related to its glycosylation consisting of sialylated and unsialylated Tn-antigens and core 1 and core 2 structures. The glycans on lubricin have also been suggested to be involved in crosslinking and stabilization of the lubricating superficial layer of cartilage by mediating interaction between lubricin and galectin-3. However, with the spectrum of glycans being found on lubricin, the glycan candidates involved in this interaction were unknown. Here, we confirm that the core 2 O-linked glycans mediate this lubricin-galectin-3 interaction, shown by surface plasmon resonance data indicating that recombinant lubricin (rhPRG4) devoid of core 2 structures did not bind to recombinant galectin-3. Conversely, transfection of Chinese hamster ovary cells with the core 2 GlcNAc transferase acting on a mucin-type O-glycoprotein displayed increased galectin-3 binding. Both the level of galectin-3 and the galectin-3 interactions with synovial lubricin were found to be decreased in late-stage OA patients, coinciding with an increase in unsialylated core 1 O-glycans (T-antigens) and Tn-antigens. These data suggest a defect in crosslinking of surface-active molecules in OA and provide novel insights into OA molecular pathology.


Assuntos
Proteínas Sanguíneas/metabolismo , Galectinas/metabolismo , Osteoartrite/metabolismo , Proteoglicanas/metabolismo , Membrana Sinovial/metabolismo , Adulto , Idoso , Animais , Proteínas Sanguíneas/genética , Células CHO , Cricetulus , Feminino , Galectinas/genética , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/genética , Osteoartrite/patologia , Proteoglicanas/genética , Membrana Sinovial/patologia
15.
Cell Res ; 30(10): 885-901, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32686768

RESUMO

Osteosarcoma (OS) is the most frequent primary malignant bone tumor in urgent need of better therapies. Using genetically modified mouse models (GEMMs), we demonstrate that Wnt signaling promotes c-Fos-induced OS formation via the actions of the collagen-modifying enzyme Loxl2. c-Fos/AP-1 directly regulates the expression of the Wnt ligands Wnt7b and Wnt9a in OS cells through promoter binding, and Wnt7b and Wnt9a in turn promote Loxl2 expression in murine and human OS cells through the transcription factors Zeb1 and Zeb2. Concordantly, inhibition of Wnt ligand secretion by inactivating the Wnt-less (Wls) gene in osteoblasts in c-Fos GEMMs either early or in a therapeutic setting reduces Loxl2 expression and progression of OS. Wls-deficient osteosarcomas proliferate less, are less mineralized and are enriched in fibroblastic cells surrounded by collagen fibers. Importantly, Loxl2 inhibition using either the pan-Lox inhibitor BAPN or a specific inducible shRNA reduces OS cell proliferation in vitro and decreases tumor growth and lung colonization in murine and human orthotopic OS transplantation models. Finally, OS development is delayed in c-Fos GEMMs treated with BAPN or with specific Loxl2 blocking antibodies. Congruently, a strong correlation between c-FOS, LOXL2 and WNT7B/WNT9A expression is observed in human OS samples, and c-FOS/LOXL2 co-expression correlates with OS aggressiveness and decreased patient survival. Therefore, therapeutic targeting of Wnt and/or Loxl2 should be considered to potentiate the inadequate current treatments for pediatric, recurrent, and metastatic OS.


Assuntos
Aminoácido Oxirredutases/metabolismo , Regulação Neoplásica da Expressão Gênica , Osteossarcoma/metabolismo , Via de Sinalização Wnt , Animais , Neoplasias Ósseas/metabolismo , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Endogâmicos C57BL
16.
Int J Mol Sci ; 21(8)2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32316583

RESUMO

Receptor tyrosine kinases (RTKs) orchestrate cell motility and differentiation. Deregulated RTKs may promote cancer and are prime targets for specific inhibitors. Increasing evidence indicates that resistance to inhibitor treatment involves receptor cross-interactions circumventing inhibition of one RTK by activating alternative signaling pathways. Here, we used single-molecule super-resolution microscopy to simultaneously visualize single MET and epidermal growth factor receptor (EGFR) clusters in two cancer cell lines, HeLa and BT-20, in fixed and living cells. We found heteromeric receptor clusters of EGFR and MET in both cell types, promoted by ligand activation. Single-protein tracking experiments in living cells revealed that both MET and EGFR respond to their cognate as well as non-cognate ligands by slower diffusion. In summary, for the first time, we present static as well as dynamic evidence of the presence of heteromeric clusters of MET and EGFR on the cell membrane that correlates with the relative surface expression levels of the two receptors.


Assuntos
Membrana Celular/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Imagem Individual de Molécula/métodos , Linhagem Celular Tumoral , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/metabolismo , Células HeLa , Fator de Crescimento de Hepatócito/farmacologia , Humanos , Ligantes , Complexos Multiproteicos/metabolismo , Transdução de Sinais
17.
Sci Rep ; 10(1): 4215, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32144329

RESUMO

Lubricin (PRG4) is a mucin type protein that plays an important role in maintaining normal joint function by providing lubrication and chondroprotection. Improper lubricin modification and degradation has been observed in idiopathic osteoarthritis (OA), while the detailed mechanism still remains unknown. We hypothesized that the protease cathepsin G (CG) may participate in degrading lubricin in synovial fluid (SF). The presence of endogenous CG in SF was confirmed in 16 patients with knee OA. Recombinant human lubricin (rhPRG4) and native lubricin purified from the SF of patients were incubated with exogenous CG and lubricin degradation was monitored using western blot, staining by Coomassie or Periodic Acid-Schiff base in gels, and with proteomics. Full length lubricin (∼300 kDa), was efficiently digested with CG generating a 25-kDa protein fragment, originating from the densely glycosylated mucin domain (∼250 kDa). The 25-kDa fragment was present in the SF from OA patients, and the amount was increased after incubation with CG. A CG digest of rhPRG4 revealed 135 peptides and 72 glycopeptides, and confirmed that the protease could cleave in all domains of lubricin, including the mucin domain. Our results suggest that synovial CG may take part in the degradation of lubricin, which could affect the pathological decrease of the lubrication in degenerative joint disease.


Assuntos
Catepsina G/metabolismo , Glicoproteínas/metabolismo , Osteoartrite/fisiopatologia , Proteoma/metabolismo , Líquido Sinovial/metabolismo , Idoso , Idoso de 80 Anos ou mais , Feminino , Glicopeptídeos , Glicosilação , Humanos , Masculino , Pessoa de Meia-Idade
18.
Med Biol Eng Comput ; 58(1): 187-209, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31813091

RESUMO

Quantitative assessment of microcalcification (MC) cluster image quality is presented, in terms of cluster signal-difference-to-noise ratio (SDNR) intercomparison among digital breast tomosynthesis (DBT) and 2-dimensional (2D) and synthetic-2-dimensional (s2D) mammography. A phantom that provides realistic appearance of MC clusters located in uniform and nonuniform background was imaged in 2D and DBT, considering various scattering conditions. MC cluster SDNR differentiation is investigated with respect to MC particle size (uniform background) and surrounding parenchyma density (nonuniform background). An accurate MC cluster segmentation method was used to delineate individual MC particles and estimate MC cluster SDNR. Analysis of the uniform part of the phantom indicated higher performance of DBT and 2D over s2D for the smallest cluster size (106-177 µm), no difference among mammographic modes for the largest MC cluster (224-354 µm), and enhanced role of 2D for decreasing cluster size and increasing scattering. Analysis of the nonuniform part of the phantom indicated DBT performed better than 2D and s2D in case of dense parenchyma pattern, while 2D and s2D did not differ across parenchyma density patterns and scattering conditions. The presented MC cluster SDNR analysis was capable of revealing subtle differences among mammographic modes and suggests a methodology for clinical image quality assessment. Graphical abstract.


Assuntos
Mama/diagnóstico por imagem , Mama/patologia , Calcinose/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Mamografia , Feminino , Humanos , Tamanho da Partícula , Imagens de Fantasmas , Reprodutibilidade dos Testes , Razão Sinal-Ruído
19.
Nano Lett ; 19(11): 8245-8249, 2019 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-31621335

RESUMO

Fluorescence methods are important tools in modern biology. Direct labeling of biomolecules with a fluorophore might, however, change interaction surfaces. Here, we introduce a competitive binding assay in combination with fluorescence correlation spectroscopy that reports binding affinities of both labeled and unlabeled biomolecules to their binding target. We investigated how fluorophore labels at different positions of a DNA oligonucleotide affect hybridization to a complementary oligonucleotide and found dissociation constants varying within 2 orders of magnitude. We next demonstrated that placing a fluorophore label at position Leu280 in the protein ligand internalin B does not alter the binding affinity to the MET receptor tyrosine kinase, compared to unlabeled internalin B. Our approach is simple to implement and can be applied to investigate the influence of fluorophore labels in a large variety of biomolecular interactions.


Assuntos
DNA/química , Corantes Fluorescentes/química , Oligonucleotídeos/química , Ligação Competitiva , Humanos , Modelos Moleculares , Hibridização de Ácido Nucleico/métodos , Mapeamento de Interação de Proteínas/métodos , Espectrometria de Fluorescência/métodos
20.
Biophys J ; 114(10): 2432-2443, 2018 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-29650369

RESUMO

The dynamics of biomolecules in the plasma membrane is of fundamental importance to understanding cellular processes. Cellular signaling often starts with extracellular ligand binding to a membrane receptor, which then transduces an intracellular signal. Ligand binding and receptor-complex activation often involve a complex rearrangement of proteins in the membrane, which results in changes in diffusion properties. Two widely used methods to characterize biomolecular diffusion are single-particle tracking (SPT) and imaging total internal reflection fluorescence correlation spectroscopy (ITIR-FCS). Here, we compare the results of recovered diffusion coefficients and mean-square displacements of the two methods by simulations of free, domain-confined, or meshwork diffusion. We introduce, to our knowledge, a new method for the determination of confinement radii from ITIR-FCS data. We further establish and demonstrate simultaneous SPT/ITIR-FCS for direct comparison within living cells. Finally, we compare the results obtained by SPT and ITIR-FCS for the receptor tyrosine kinase MET. Our results show that SPT and ITIR-FCS yield complementary information on diffusion properties of biomolecules in cell membranes.


Assuntos
Membrana Celular/metabolismo , Espectrometria de Fluorescência , Difusão
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