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1.
Cells ; 13(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38920701

RESUMO

While the transcription factor GATA-3 is well-established for its crucial role in T cell development, its specific influence on invariant natural killer T (iNKT) cells remains relatively unexplored. Using flow cytometry and single-cell transcriptomic analysis, we demonstrated that GATA-3 deficiency in mice leads to the absence of iNKT2 and iNKT17 cell subsets, as well as an altered distribution of iNKT1 cells. Thymic iNKT cells lacking GATA-3 exhibited diminished expression of PLZF and T-bet, key transcription factors involved in iNKT cell differentiation, and reduced production of Th2, Th17, and cytotoxic effector molecules. Single-cell transcriptomics revealed a comprehensive absence of iNKT17 cells, a substantial reduction in iNKT2 cells, and an increase in iNKT1 cells in GATA-3-deficient thymi. Differential expression analysis highlighted the regulatory role of GATA-3 in T cell activation signaling and altered expression of genes critical for iNKT cell differentiation, such as Icos, Cd127, Eomes, and Zbtb16. Notably, restoration of Icos, but not Cd127, expression could rescue iNKT cell development in GATA-3-deficient mice. In conclusion, our study demonstrates the pivotal role of GATA-3 in orchestrating iNKT cell effector lineage differentiation through the regulation of T cell activation pathways and Icos expression, providing insights into the molecular mechanisms governing iNKT cell development and function.


Assuntos
Diferenciação Celular , Linhagem da Célula , Fator de Transcrição GATA3 , Células T Matadoras Naturais , Animais , Fator de Transcrição GATA3/metabolismo , Fator de Transcrição GATA3/genética , Células T Matadoras Naturais/citologia , Células T Matadoras Naturais/metabolismo , Diferenciação Celular/genética , Camundongos , Linhagem da Célula/genética , Camundongos Endogâmicos C57BL , RNA-Seq , Análise de Célula Única , Camundongos Knockout , Análise da Expressão Gênica de Célula Única
2.
Sci Adv ; 10(11): eadd9342, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38478609

RESUMO

Tumors represent ecosystems where subclones compete during tumor growth. While extensively investigated, a comprehensive picture of the interplay of clonal lineages during dissemination is still lacking. Using patient-derived pancreatic cancer cells, we created orthotopically implanted clonal replica tumors to trace clonal dynamics of unperturbed tumor expansion and dissemination. This model revealed the multifaceted nature of tumor growth, with rapid changes in clonal fitness leading to continuous reshuffling of tumor architecture and alternating clonal dominance as a distinct feature of cancer growth. Regarding dissemination, a large fraction of tumor lineages could be found at secondary sites each having distinctive organ growth patterns as well as numerous undescribed behaviors such as abortive colonization. Paired analysis of primary and secondary sites revealed fitness as major contributor to dissemination. From the analysis of pro- and nonmetastatic isogenic subclones, we identified a transcriptomic signature able to identify metastatic cells in human tumors and predict patients' survival.


Assuntos
Ecossistema , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Perfilação da Expressão Gênica , Transcriptoma
3.
Sci Adv ; 10(13): eadk5386, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38536927

RESUMO

While pancreatic ductal adenocarcinomas (PDACs) are addicted to KRAS-activating mutations, inhibitors of downstream KRAS effectors, such as the MEK1/2 kinase inhibitor trametinib, are devoid of therapeutic effects. However, the extensive rewiring of regulatory circuits driven by the attenuation of the KRAS pathway may induce vulnerabilities of therapeutic relevance. An in-depth molecular analysis of the transcriptional and epigenomic alterations occurring in PDAC cells in the initial hours after MEK1/2 inhibition by trametinib unveiled the induction of endogenous retroviruses (ERVs) escaping epigenetic silencing, leading to the production of double-stranded RNAs and the increased expression of interferon (IFN) genes. We tracked ERV activation to the early induction of the transcription factor ELF3, which extensively bound and activated nonsilenced retroelements and synergized with IRF1 (interferon regulatory factor 1) in the activation of IFNs and IFN-stimulated genes. Trametinib-induced viral mimicry in PDAC may be exploited in the rational design of combination therapies in immuno-oncology.


Assuntos
Carcinoma Ductal Pancreático , Retrovirus Endógenos , Neoplasias Pancreáticas , Humanos , Retrovirus Endógenos/genética , Transdução de Sinais , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo
4.
Clin Cardiol ; 47(1): e24175, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37872851

RESUMO

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) has low survival rates, and few patients achieve a desirable neurological outcome. Anemia is common among OHCA patients and has been linked to worse outcomes, but its impact following the return of spontaneous circulation (ROSC) is unclear. This study examines the relationship between anemia burden and clinical outcomes in OHCA patients. HYPOTHESIS: Higher anemia burden after ROSC may be related to higher mortality and worse neurologic outcomes. METHODS: Patients who experienced OHCA and had ROSC were enrolled retrospectively. Anemia burden was defined as the area under curve from the target hemoglobin level over a 72-h period after OHCA. Hemoglobin level was measured at 12-h intervals. The clinical outcomes of the study included mortality and neurological outcomes at Day 30. RESULTS: The study enrolled 258 nontraumatic OHCA patients who achieved ROSC between January 2017 and December 2021. Among the 162 patients who survived more than 72 h, a higher anemia burden, specifically target hemoglobin levels below 7 (hazard ratio [HR]: 1.129, 95% confidence interval [CI]: 1.013-1.259, p = .029), 8 (HR: 1.099, 95% CI: 1.014-1.191, p = .021), and 9 g/dL (HR: 1.066, 95% CI: 1.001-1.134, p = .046) was associated with higher 30-day mortality. Additionally, anemia burden with target hemoglobin levels below 7 (HR: 1.129, 95% CI: 1.016-1.248; p = .024) and 8 g/dL (HR: 1.088; 95% CI: 1.008-1.174, p = .031) was linked to worse neurological outcomes. CONCLUSIONS: Anemia burden predicts 30-day mortality and neurological outcomes in OHCA patients who survive more than 72 h. Maintaining higher hemoglobin levels within the first 72 h after ROSC may improve short-term outcomes.


Assuntos
Anemia , Reanimação Cardiopulmonar , Parada Cardíaca Extra-Hospitalar , Humanos , Parada Cardíaca Extra-Hospitalar/diagnóstico , Parada Cardíaca Extra-Hospitalar/terapia , Estudos Retrospectivos , Anemia/complicações , Anemia/diagnóstico , Anemia/epidemiologia , Hemoglobinas
5.
Thorac Cancer ; 15(4): 339-346, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38149471

RESUMO

BACKGROUND: Thymic carcinoma is a rare disease with an incidence of around 0.5 cases per million with a poor prognosis. The aim of this study was to assess patient outcomes with advanced thymic carcinoma receiving first-line chemotherapy. METHODS: In our retrospective cohort study, we included patients who underwent treatment for metastatic thymic carcinoma between January 2013 to December 2019 in our hospital. Overall survival, progression-free survival (PFS), objective response rates (ORR) and chemotherapy regimens were assessed and analyzed. RESULTS: A total of 27 patients were retrospectively analyzed. All patients received a platinum (cisplatin or carboplatin) based regimen as first-line chemotherapy (29.6% received ADOC, 11.1% received PE, 40.7% received CP, 14.8% received CAP). The median PFS on first-line chemotherapy was 199 days. The response rate was 40.7%. Median overall survival (OS) was 585 days. Positive CD5 staining was associated with better PFS. CONCLUSION: We highlight the critical role of platinum-based chemotherapy agents as a primary treatment modality in advanced thymic carcinoma, underscoring the efficacy of platinum as a first-line option for recurrent disease, even in cases previously treated with platinum. Additionally, our findings indicate that CD5 positivity could be associated with improved PFS, suggesting its potential as a prognostic marker.


Assuntos
Antineoplásicos , Timoma , Neoplasias do Timo , Humanos , Timoma/tratamento farmacológico , Timoma/patologia , Estudos Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antineoplásicos/uso terapêutico , Cisplatino/uso terapêutico , Platina/uso terapêutico , Neoplasias do Timo/tratamento farmacológico , Neoplasias do Timo/patologia , Resultado do Tratamento
6.
Front Immunol ; 14: 1290585, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38094295

RESUMO

Introduction: MZB1 is an endoplasmic reticulum residential protein preferentially expressed in plasma cells, marginal zone and B1 B cells. Recent studies on murine B cells show that it interacts with the tail piece of IgM and IgA heavy chain and promotes the secretion of these two classes of immunoglobulin. However, its role in primary human B cells has yet to be determined and how its function is regulated is still unknown. The conversion of peptidylarginine to peptidylcitrulline, also known as citrullination, by peptidylarginine deiminases (PADs) can critically influence the function of proteins in immune cells, such as neutrophils and T cells; however, the role of PADs in B cells remains to be elucidated. Method: An unbiased analysis of human lung citrullinome was conducted to identify citrullinated proteins that are enriched in several chronic lung diseases, including rheumatoid arthritis-associated interstitial lung disease (RA-ILD), chronic obstructive pulmonary disease, and idiopathic pulmonary fibrosis, compared to healthy controls. Mass spectrometry, site-specific mutagenesis, and western blotting were used to confirm the citrullination of candidate proteins. Their citrullination was suppressed by pharmacological inhibition or genetic ablation of PAD2 and the impact of their citrullination on the function and differentiation of human B cells was examined with enzyme-linked immunosorbent assay, flow cytometry, and co-immunoprecipitation. Results: Citrullinated MZB1 was preferentially enriched in RA-ILD but not in other chronic lung diseases. MZB1 was a substrate of PAD2 and was citrullinated during the differentiation of human plasmablasts. Ablation or pharmacological inhibition of PAD2 in primary human B cells attenuated the secretion of IgM and IgA but not IgG or the differentiation of IgM or IgA-expressing plasmablasts, recapitulating the effect of ablating MZB1. Furthermore, the physical interaction between endogenous MZB1 and IgM/IgA was attenuated by pharmacological inhibition of PAD2. Discussion: Our data confirm the function of MZB1 in primary human plasmablasts and suggest that PAD2 promotes IgM/IgA secretion by citrullinating MZB1, thereby contributing to the pathogenesis of rheumatoid arthritis and RA-ILD.


Assuntos
Artrite Reumatoide , Fibrose Pulmonar Idiopática , Doenças Pulmonares Intersticiais , Humanos , Camundongos , Animais , Desiminases de Arginina em Proteínas/genética , Proteínas/metabolismo , Imunoglobulina A , Imunoglobulina M
7.
Philos Trans R Soc Lond B Biol Sci ; 378(1890): 20220244, 2023 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-37778384

RESUMO

Proteins once translated are subjected to post-translational modifications (PTMs) that can critically modify their characteristics. Citrullination is a unique type of PTM that is catalysed by peptidylarginine deiminase (PAD) enzymes, which regulate a multitude of physiological functions such as apoptosis, gene expression and immune response by altering the structure and function of cellular proteins. However, emerging data have unravelled compelling evidence to support that PAD-mediated citrullination is not exclusive to cellular proteins; rather citrullination of extracellular matrix (ECM) proteins also plays a major contributing role in various physiological/pathological conditions. Here, we discuss putative mechanisms for citrullination-induced alterations in the function of ECM proteins. Further, we put emphasis on influential roles of ECM citrullination in various pathological scenarios to underscore the clinical potential of its manipulation in human diseases. This article is part of the Theo Murphy meeting issue 'The virtues and vices of protein citrullination'.


Assuntos
Citrulinação , Proteínas , Humanos , Desiminases de Arginina em Proteínas/genética , Desiminases de Arginina em Proteínas/metabolismo , Proteínas/genética , Processamento de Proteína Pós-Traducional
8.
Discov Nano ; 18(1): 77, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37382747

RESUMO

This study presents a comprehensive analysis of the structural and optical properties of an InGaN-based red micro-LED with a high density of V-shaped pits, offering insights for enhancing emission efficiency. The presence of V-shaped pits is considered advantageous in reducing non-radiative recombination. Furthermore, to systematically investigate the properties of localized states, we conducted temperature-dependent photoluminescence (PL). The results of PL measurements indicate that deep localization in the red double quantum wells can limit carrier escape and improve radiation efficiency. Through a detailed analysis of these results, we extensively investigated the direct impact of epitaxial growth on the efficiency of InGaN red micro-LEDs, thereby laying the foundation for improving efficiency in InGaN-based red micro-LEDs.

9.
Opt Lett ; 48(7): 1746-1749, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37221756

RESUMO

Two-dimensional fractal topologies featuring (scaling) self-similarity, dense set of Bragg (diffraction) peaks, and inherent rotation symmetry, which are not achievable with regular grid-matrix geometries, exhibit optical robustness against structural damage and noise immunity of optical transmission paths. In this work, we numerically and experimentally demonstrate phase holograms using fractal plane-divisions. By taking advantage of the symmetries of the fractal topology, we propose numerical algorithms to design the fractal holograms. This algorithm solves the inapplicability of the conventional iterative Fourier transform algorithm (IFTA) method and enables efficient optimizations of millions of adjustable parameters in the optical element. Experimental samples show that the alias and replica noises in the image plane of fractal holograms are clearly suppressed, facilitating applications for high-accuracy and compact requirements.

10.
Proc Natl Acad Sci U S A ; 120(21): e2209639120, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37186844

RESUMO

Renal medullary carcinoma (RMC) is an aggressive kidney cancer that almost exclusively develops in individuals with sickle cell trait (SCT) and is always characterized by loss of the tumor suppressor SMARCB1. Because renal ischemia induced by red blood cell sickling exacerbates chronic renal medullary hypoxia in vivo, we investigated whether the loss of SMARCB1 confers a survival advantage under the setting of SCT. Hypoxic stress, which naturally occurs within the renal medulla, is elevated under the setting of SCT. Our findings showed that hypoxia-induced SMARCB1 degradation protected renal cells from hypoxic stress. SMARCB1 wild-type renal tumors exhibited lower levels of SMARCB1 and more aggressive growth in mice harboring the SCT mutation in human hemoglobin A (HbA) than in control mice harboring wild-type human HbA. Consistent with established clinical observations, SMARCB1-null renal tumors were refractory to hypoxia-inducing therapeutic inhibition of angiogenesis. Further, reconstitution of SMARCB1 restored renal tumor sensitivity to hypoxic stress in vitro and in vivo. Together, our results demonstrate a physiological role for SMARCB1 degradation in response to hypoxic stress, connect the renal medullary hypoxia induced by SCT with an increased risk of SMARCB1-negative RMC, and shed light into the mechanisms mediating the resistance of SMARCB1-null renal tumors against angiogenesis inhibition therapies.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Traço Falciforme , Animais , Humanos , Camundongos , Carcinoma de Células Renais/patologia , Hipóxia/genética , Hipóxia/metabolismo , Rim/metabolismo , Neoplasias Renais/patologia , Traço Falciforme/genética , Traço Falciforme/metabolismo , Proteína SMARCB1/genética , Proteína SMARCB1/metabolismo
11.
Nat Commun ; 14(1): 2194, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-37069167

RESUMO

Mitochondria are hubs where bioenergetics, redox homeostasis, and anabolic metabolism pathways integrate through a tightly coordinated flux of metabolites. The contributions of mitochondrial metabolism to tumor growth and therapy resistance are evident, but drugs targeting mitochondrial metabolism have repeatedly failed in the clinic. Our study in pancreatic ductal adenocarcinoma (PDAC) finds that cellular and mitochondrial lipid composition influence cancer cell sensitivity to pharmacological inhibition of electron transport chain complex I. Profiling of patient-derived PDAC models revealed that monounsaturated fatty acids (MUFAs) and MUFA-linked ether phospholipids play a critical role in maintaining ROS homeostasis. We show that ether phospholipids support mitochondrial supercomplex assembly and ROS production; accordingly, blocking de novo ether phospholipid biosynthesis sensitized PDAC cells to complex I inhibition by inducing mitochondrial ROS and lipid peroxidation. These data identify ether phospholipids as a regulator of mitochondrial redox control that contributes to the sensitivity of PDAC cells to complex I inhibition.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Espécies Reativas de Oxigênio/metabolismo , Éteres Fosfolipídicos/metabolismo , Mitocôndrias/metabolismo , Fosfolipídeos/metabolismo , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/metabolismo , Homeostase
12.
BMJ Open ; 13(2): e055404, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36813495

RESUMO

OBJECTIVE: There are limited data on the influence of ethnicity on diabetic retinopathy (DR). We sought to determine the distribution of DR by ethnic group in Australia. DESIGN: Clinic-based cross-sectional study. SETTING: Participants with diabetes in a defined geographical region of Sydney, Australia, who attended a tertiary retina referral clinic. PARTICIPANTS: The study recruited 968 participants. INTERVENTION: Participants underwent a medical interview and retinal photography and scanning. PRIMARY OUTCOME MEASURES: DR was defined from two-field retinal photographs. Diabetic macular oedema (DMO) was defined from spectral domain optical coherence tomography (OCT-DMO). The main outcomes were any DR, proliferative DR (PDR), clinically significant macular oedema (CSME), OCT-DMO and sight-threatening DR (STDR). RESULTS: There was high proportion of any DR (52.3%), PDR (6.3%), CSME (19.7%), OCT-DMO (28.9%) and STDR (31.5%) in people attending a tertiary retinal clinic. Participants of Oceanian ethnicity had the highest proportion of any DR and STDR (70.4% and 48.1%, respectively), while the lowest proportion was in participants of East Asian ethnicity (38.3% and 15.8%, respectively). Proportion of any DR and STDR in Europeans was 54.5% and 30.3%, respectively. Independent predictive factors for diabetic eye disease were ethnicity, longer duration of diabetes, higher glycated haemoglobin and higher blood pressure. Even after adjusting for risk factors, Oceanian ethnicity remained associated with twofold higher odds of any DR (adjusted OR 2.10, 95% CI 1.10 to 4.00) and all other forms of DR including STDR (adjusted OR 2.22, 95% CI 1.19 to 4.15). CONCLUSION: In people attending a tertiary retinal clinic, the proportion of people with DR varies among ethnic groups. The high proportion in persons of Oceanian ethnicity suggests a need for targeted screening of this at-risk group. In addition to traditional risks factors, ethnicity may be an additional independent predictor of DR.


Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Edema Macular , Humanos , Retinopatia Diabética/diagnóstico , Etnicidade , Edema Macular/etiologia , Estudos Transversais , Retina , Diabetes Mellitus Tipo 2/complicações
13.
ESC Heart Fail ; 10(2): 1449-1453, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36652996

RESUMO

Furosemide, a loop diuretic, is commonly used to treat fluid overload symptoms and heart failure. Drug-induced immune haemolytic anaemia is an unusual drug-adverse event. Furosemide-induced haemolysis is even rarer. This case report presents a 91-year-old male who developed acute haemolytic anaemia 3 days after initiating furosemide to treat myocardial infarction complicated with acute decompensated heart failure. He had increased lactate dehydrogenase and unconjugated bilirubin with undetectable haptoglobin, which indicated the destruction of red blood cells. Other causes for haemolytic anaemia, including hereditary, microangiopathic haemolytic anaemia, and paroxysmal nocturnal haemoglobinuria, were also excluded. He improved with drug cessation and a short course of glucocorticoids. This report aims to raise awareness of this rare complication caused by commonly prescribed drugs. Despite a negative result of a direct antiglobulin test, physicians must remain suspicious of drug-induced immune haemolytic anaemia in unclear cases of haemolysis.


Assuntos
Anemia Hemolítica , Insuficiência Cardíaca , Masculino , Humanos , Idoso , Idoso de 80 Anos ou mais , Furosemida/efeitos adversos , Hemólise , Anemia Hemolítica/induzido quimicamente , Anemia Hemolítica/diagnóstico , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/complicações
14.
Polymers (Basel) ; 15(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36679318

RESUMO

In this study, we positioned three quaternary ammonium halide-containing cellulose derivatives (PQF, PQCl, PQBr) as interfacial modification layers between the nickel oxide (NiOx) and methylammonium lead iodide (MAPbI3) layers of inverted perovskite solar cells (PVSCs). Inserting PQCl between the NiOx and MAPbI3 layers improved the interfacial contact, promoted the crystal growth, and passivated the interface and crystal defects, thereby resulting in MAPbI3 layers having larger crystal grains, better crystal quality, and lower surface roughness. Accordingly, the photovoltaic (PV) properties of PVSCs fabricated with PQCl-modified NiOx layers were improved when compared with those of the pristine sample. Furthermore, the PV properties of the PQCl-based PVSCs were much better than those of their PQF- and PQBr-based counterparts. A PVSC fabricated with PQCl-modified NiOx (fluorine-doped tin oxide/NiOx/PQCl-0.05/MAPbI3/PC61BM/bathocuproine/Ag) exhibited the best PV performance, with a photoconversion efficiency (PCE) of 14.40%, an open-circuit voltage of 1.06 V, a short-circuit current density of 18.35 mA/cm3, and a fill factor of 74.0%. Moreover, the PV parameters of the PVSC incorporating the PQCl-modified NiOx were further enhanced when blending MAPbI3 with PQCl. We obtained a PCE of 16.53% for this MAPbI3:PQCl-based PVSC. This PQCl-based PVSC retained 80% of its initial PCE after 900 h of storage under ambient conditions (30 °C; 60% relative humidity).

15.
Phys Chem Chem Phys ; 24(46): 28314-28324, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36383178

RESUMO

We present explainable machine learning approaches for the accurate prediction and understanding of solvation free energies, enthalpies, and entropies for different salts in various protic and aprotic solvents. As key input features, we use fundamental contributions from the conceptual density functional theory (DFT) of solutions. The most accurate models with the highest prediction accuracy for the experimental validation data set are decision tree-based approaches such as extreme gradient boosting and extra trees, which highlight the non-linear influence of feature values on target predictions. The detailed assessment of the importance of features in terms of Gini importance criteria as well as Shapley Additive Explanations (SHAP) and permutation and reduction approaches underlines the prominent role of anion and cation solvation effects in combination with fundamental electronic properties of the solvents. These results are reasonably consistent with previous assumptions and provide a solid rationale for more recent theoretical approaches.


Assuntos
Eletrônica , Aprendizado de Máquina , Entropia , Sais , Solventes
16.
Chem Sci ; 13(29): 8526-8535, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35974768

RESUMO

Extracellular accumulation of ß amyloid peptides of 40 (Aß40) and 42 residues (Aß42) has been considered as one of the hallmarks in the pathology of Alzheimer's disease. In this work, we are able to prepare oligomeric aggregates of Aß with uniform size and monomorphic structure. Our experimental design is to incubate Aß peptides in reverse micelles (RMs) so that the peptides could aggregate only through a single nucleation process and the size of the oligomers is confined by the physical dimension of the reverse micelles. The hence obtained Aß oligomers (AßOs) are 23 nm in diameter and they belong to the category of high molecular-weight (MW) oligomers. The solid-state NMR data revealed that Aß40Os adopt the structural motif of ß-loop-ß but the chemical shifts manifested that they may be structurally different from low-MW AßOs and mature fibrils. From the thioflavin-T results, we found that high-MW Aß42Os can accelerate the fibrillization of Aß40 monomers. Our protocol allows performing cross-seeding experiments among oligomeric species. By comparing the chemical shifts of Aß40Os cross seeded by Aß42Os and those of Aß40Os prepared in the absence of Aß42Os, we observed that the chemical states of E11, K16, and E22 were altered, whereas the backbone conformation of the ß-sheet region near the C-terminus was structurally invariant. The use of reverse micelles allows hitherto the most detailed characterization of the structural variability of Aß40Os.

17.
ACS Appl Mater Interfaces ; 14(14): 16839-16845, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35363462

RESUMO

Titanium nitride (TiN), a transition-metal compound with tight covalent Ti-N bonding, has a high melting temperature and superior mechanical and chemical stabilities compared to noble metals. With a reduction in thickness, the optical transmittance of TiN films can be drastically increased, and in combination with its excellent electrical conductivity, the ultrathin and continuous TiN film can be considered as an ideal alternative of the metal oxide electrodes. However, the deposition of ultrathin and continuous metallic layer with a smooth surface morphology is a major challenge for typical deposition methods such as thermal evaporation or reactive sputtering. In particular, defects mainly related with oxygen contents and surface scattering can significantly limit the performance of ultrathin TiN films. In this work, ultrathin TiN films with 2-10 nm in thickness are grown by using the nitrogen plasma-assisted molecular-beam epitaxy (MBE) method in an ultrahigh vacuum environment. Excellent surface morphology with a root-mean-square roughness of ≤0.12 nm and a high optical transparency of 75% over the whole visible regime are achieved for ultrathin TiN epitaxial films. The dielectric properties determined by the spectroscopic ellipsometry and the electrical properties measured by the terahertz spectroscopy and the Hall effect method reveal that the percolation thickness of the TiN epitaxial film is less than 2.4 nm and its electrical conductivity is higher than 1.1 × 104 Ω-1 cm-1. These features make MBE-grown ultrathin TiN epitaxial films a good candidate for robust, low cost, and large-area transparent conductive electrodes.

18.
Am J Ophthalmol Case Rep ; 25: 101342, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35243133

RESUMO

PURPOSE: Presentation of a unique case of large, star-shaped retinal tear associated with orbital cosmetic filler injection. OBSERVATION: A 55-year-old healthy female presented to emergency department with sudden onset of blurred vision on her left eye occurred after an orbital cosmetic filler injection containing hyaluronic acid (HA) performed by an aesthetic nurse. On fundus examination, the left eye showed a mild - moderate, unusual appearance vitreous haze and a large, star-shaped retinal tear temporal to macula. Optical coherence tomography (OCT) examination demonstrated a normal foveal contour without any structural damage on the retinal layers. Vitrectomy, endolaser and silicon oil tamponade were performed. Visual acuity was maintained at 6/7.5 following silicon oil removal at 6 weeks after the initial surgery. CONCLUSIONS AND IMPORTANCE: In this particular case, immediate vitrectomy is key to avoid further complications such as retinal toxicity and detachment and to maintain optimal visual acuity. Importantly, facial cosmetic filler procedure should be performed by an adequately trained individual to avoid such complications.

19.
Sci Rep ; 12(1): 2847, 2022 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-35181688

RESUMO

Rheumatoid arthritis (RA)-associated interstitial lung disease (RA-ILD) is the most common pulmonary complication of RA, increasing morbidity and mortality. Anti-citrullinated protein antibodies have been associated with the development and progression of both RA and fibrotic lung disease; however, the role of protein citrullination in RA-ILD remains unclear. Here, we demonstrate that the expression of peptidylarginine deiminase 2 (PAD2), an enzyme that catalyzes protein citrullination, is increased in lung homogenates from subjects with RA-ILD and their lung fibroblasts. Chemical inhibition or genetic knockdown of PAD2 in RA-ILD fibroblasts attenuated their activation, marked by decreased myofibroblast differentiation, gel contraction, and extracellular matrix gene expression. Treatment of RA-ILD fibroblasts with the proteoglycan syndecan-2 (SDC2) yielded similar antifibrotic effects through regulation of PAD2 expression, phosphoinositide 3-kinase/Akt signaling, and Sp1 activation in a CD148-dependent manner. Furthermore, SDC2-transgenic mice exposed to bleomycin-induced lung injury in an inflammatory arthritis model expressed lower levels of PAD2 and were protected from the development of pulmonary fibrosis. Together, our results support a SDC2-sensitive profibrotic role for PAD2 in RA-ILD fibroblasts and identify PAD2 as a promising therapeutic target of RA-ILD.


Assuntos
Artrite Reumatoide/genética , Lesão Pulmonar/genética , Proteína-Arginina Desiminase do Tipo 2/genética , Fibrose Pulmonar/genética , Sindecana-2/genética , Animais , Anticorpos Antiproteína Citrulinada/genética , Artrite Reumatoide/complicações , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/patologia , Bleomicina/toxicidade , Citrulinação/genética , Fibroblastos/metabolismo , Regulação da Expressão Gênica/genética , Humanos , Pulmão/metabolismo , Pulmão/patologia , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/complicações , Lesão Pulmonar/patologia , Camundongos , Camundongos Transgênicos , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Fibrose Pulmonar/complicações , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/patologia , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores , Fator de Transcrição Sp1/genética
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