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1.
Immunity ; 46(1): 38-50, 2017 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-27986454

RESUMO

Lipopolysaccharide (LPS), the major component of the outer membrane of Gram-negative bacteria, binds Toll-like receptor 4 (TLR4)-MD2 complex and activates innate immune responses. LPS transfer to TLR4-MD2 is catalyzed by both LPS binding protein (LBP) and CD14. To define the sequential molecular interactions underlying this transfer, we reconstituted in vitro the entire LPS transfer process from LPS micelles to TLR4-MD2. Using electron microscopy and single-molecule approaches, we characterized the dynamic intermediate complexes for LPS transfer: LBP-LPS micelles, CD14-LBP-LPS micelle, and CD14-LPS-TLR4-MD2 complex. A single LBP molecule bound longitudinally to LPS micelles catalyzed multi-rounds of LPS transfer to CD14s that rapidly dissociated from LPB-LPS complex upon LPS transfer via electrostatic interactions. Subsequently, the single LPS molecule bound to CD14 was transferred to TLR4-MD2 in a TLR4-dependent manner. The definition of the structural determinants of the LPS transfer cascade to TLR4 may enable the development of targeted therapeutics for intervention in LPS-induced sepsis.


Assuntos
Proteínas de Fase Aguda/imunologia , Proteínas de Transporte/imunologia , Receptores de Lipopolissacarídeos/imunologia , Lipopolissacarídeos/imunologia , Antígeno 96 de Linfócito/imunologia , Glicoproteínas de Membrana/imunologia , Receptor 4 Toll-Like/imunologia , Animais , Humanos , Camundongos , Microscopia Eletrônica de Transmissão , Transdução de Sinais/imunologia
2.
Nano Lett ; 24(6): 1882-1890, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38198287

RESUMO

Understanding the spatial organization of membrane proteins is crucial for unraveling key principles in cell biology. The reaction-diffusion model is commonly used to understand biochemical patterning; however, applying reaction-diffusion models to subcellular phenomena is challenging because of the difficulty in measuring protein diffusivity and interaction kinetics in the living cell. In this work, we investigated the self-organization of the plasmalemma vesicle-associated protein (PLVAP), which creates regular arrangements of fenestrated ultrastructures, using single-molecule tracking. We demonstrated that the spatial organization of the ultrastructures is associated with a decrease in the association rate by actin destabilization. We also constructed a reaction-diffusion model that accurately generates a hexagonal array with the same 130 nm spacing as the actual scale and informs the stoichiometry of the ultrastructure, which can be discerned only through electron microscopy. Through this study, we integrated single-molecule experiments and reaction-diffusion modeling to surpass the limitations of static imaging tools and proposed emergent properties of the PLVAP ultrastructure.


Assuntos
Proteínas de Transporte , Proteínas de Membrana , Proteínas de Membrana/metabolismo , Difusão , Modelos Biológicos
3.
Am J Hematol ; 99(7): 1220-1229, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38629639

RESUMO

Polycythemia vera (PV) is a clonal disorder arising from the acquired somatic mutations of the JAK2 gene, including JAK2V617F or several others in exon 12. A 38-year-old female had a stroke at age 32 and found to have elevated hemoglobin, normal leukocytes, normal platelets, and tested negative for JAK2V617F and exon 12 mutations. Next generation sequencing revealed a novel mutation: JAK2R715T in the pseudokinase domain (JH2) at 47.5%. Its presence in her nail DNA confirmed a germline origin. Her mother and her son similarly had erythrocytosis and a JAK2R715T mutation. Computer modeling indicated gain-of-function JAK2 activity. The propositus and her mother had polyclonal myelopoiesis, ruling out another somatic mutation-derived clonal hematopoiesis. Some erythroid progenitors of all three generations grew without erythropoietin, a hallmark of PV. The in vitro reporter assay confirmed increased activity of the JAK2R715T kinase. Similar to PV, the JAK2R715T native cells have increased STAT5 phosphorylation, augmented transcripts of prothrombotic and inflammatory genes, and decreased KLF2 transcripts. The propositus was not controlled by hydroxyurea, and JAK2 inhibitors were not tolerated; however, Ropeginterferon-alfa-2b (Ropeg-IFN-α) induced a remission. Ropeg-IFN-α treatment also reduced JAK2 activity in the propositus, her mother and JAK2V617F PV subjects. We report dominantly inherited erythrocytosis secondary to a novel germline JAK2R715T gain-of-function mutation with many but not all comparable molecular features to JAK2V617F PV. We also document a previously unreported inhibitory mechanism of JAK2 signaling by Ropeg-IFN-α.


Assuntos
Mutação em Linhagem Germinativa , Janus Quinase 2 , Policitemia , Adulto , Feminino , Humanos , Mutação com Ganho de Função , Interferon-alfa/uso terapêutico , Janus Quinase 2/genética , Linhagem , Policitemia/genética , Policitemia/tratamento farmacológico , Policitemia Vera/genética , Policitemia Vera/tratamento farmacológico
4.
Opt Express ; 31(3): 4920-4931, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36785447

RESUMO

Localized light matter interaction at a resonant nanostructure facilitates spectrally selective transmission of light, which has led to demonstrations of ultrathin metasurface based optical filters. Unfortunately, due to the nature of Lorentzian spectral line shape in such resonances, it is inevitable to suffer significant spectral crosstalk. In this work, we demonstrate a conceptually new type of spectral filter which exhibits near flat-top bandpass with minimized spectral overlaps. To realize this, we leverage the recent development of non-local resonance in dielectric nanostructure to design a double-layered optical filter with performance comparable to the ideal spectral filters. The designed metasurface shows averaged transmission of more than 90% across the target spectral band and suppressed transmission of less than 10% out of the spectral band.

5.
Mol Cell ; 57(2): 290-303, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25557547

RESUMO

SMC condensin complexes are central modulators of chromosome superstructure in all branches of life. Their SMC subunits form a long intramolecular coiled coil, which connects a constitutive "hinge" dimerization domain with an ATP-regulated "head" dimerization module. Here, we address the structural arrangement of the long coiled coils in SMC complexes. We unequivocally show that prokaryotic Smc-ScpAB, eukaryotic condensin, and possibly also cohesin form rod-like structures, with their coiled coils being closely juxtaposed and accurately anchored to the hinge. Upon ATP-induced binding of DNA to the hinge, however, Smc switches to a more open configuration. Our data suggest that a long-distance structural transition is transmitted from the Smc head domains to regulate Smc-ScpAB's association with DNA. These findings uncover a conserved architectural theme in SMC complexes, provide a mechanistic basis for Smc's dynamic engagement with chromosomes, and offer a molecular explanation for defects in Cornelia de Lange syndrome.


Assuntos
Proteínas de Bactérias/ultraestrutura , Proteínas de Ciclo Celular/ultraestrutura , DNA Bacteriano/química , Pyrococcus furiosus , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Ciclo Celular/química , Cristalografia por Raios X , Modelos Moleculares , Dados de Sequência Molecular , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Estrutura Secundária de Proteína
6.
J Nanobiotechnology ; 21(1): 242, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37507708

RESUMO

BACKGROUND: Central serous chorioretinopathy (CSC) is the fourth most prevalent retinal disease leading to age-related macular degeneration (AMD) and retinal atrophy. However, CSC's pathogenesis and therapeutic target need to be better understood. RESULTS: We investigated exosomal microRNA in the aqueous humor of CSC patients using next-generation sequencing (NGS) to identify potential biomarkers associated with CSC pathogenesis. Bioinformatic evaluations and NGS were performed on exosomal miRNAs obtained from AH samples of 62 eyes (42 CSC and 20 controls). For subgroup analysis, patients were divided into treatment responders (CSC-R, 17 eyes) and non-responders (CSC-NR, 25 eyes). To validate the functions of miRNA in CECs, primary cultured-human choroidal endothelial cells (hCEC) of the donor eyes were utilized for in vitro assays. NGS detected 376 miRNAs. Our results showed that patients with CSC had 12 significantly upregulated and 17 downregulated miRNAs compared to controls. miR-184 was significantly upregulated in CSC-R and CSC-NR patients compared to controls and higher in CSC-NR than CSC-R. In vitro assays using primary cultured-human choroidal endothelial cells (hCEC) demonstrated that miR-184 suppressed the proliferation and migration of hCECs. STC2 was identified as a strong candidate for the posttranscriptional down-regulated target gene of miR-184. CONCLUSION: Our findings suggest that exosomal miR-184 may serve as a biomarker reflecting the angiostatic capacity of CEC in patients with CSC.


Assuntos
Coriorretinopatia Serosa Central , MicroRNAs , Humanos , Humor Aquoso , Biomarcadores , Coriorretinopatia Serosa Central/diagnóstico , Coriorretinopatia Serosa Central/genética , Coriorretinopatia Serosa Central/tratamento farmacológico , Células Endoteliais , Angiofluoresceinografia/métodos , MicroRNAs/genética , MicroRNAs/uso terapêutico , Prognóstico
7.
FASEB J ; 35(3): e21403, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33559185

RESUMO

The retinal pigment epithelium (RPE) undergoes characteristic structural changes and epithelial-mesenchymal transition (EMT) during normal aging, which are exacerbated in age-related macular degeneration (AMD). Although the pathogenic mechanisms of aging and AMD remain unclear, transforming growth factor-ß1 (TGF-ß1) is known to induce oxidative stress, morphometric changes, and EMT as a senescence-promoting factor. In this study, we examined whether intravitreal injection of TGF-ß1 into the mouse eye elicits senescence-like morphological alterations in the RPE and if this can be prevented by suppressing mammalian target of rapamycin complex 1 (mTORC1) or NADPH oxidase (NOX) signaling. We verified that intravitreal TGF-ß1-induced stress fiber formation and EMT in RPE cells, along with age-associated morphometric changes, including increased variation in cell size and reduced cell density. In RPE cells, exogenous TGF-ß1 increased endogenous expression of TGF-ß1 and upregulated Smad3-ERK1/2-mTORC1 signaling, increasing reactive oxygen species (ROS) production and EMT. We demonstrated that inhibition of the mTORC1-NOX4 pathway by pretreatment with 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR), an activator of AMP-dependent protein kinase, or GKT137831, a NOX1/4 inhibitor, decreased ROS generation, prevented stress fiber formation, attenuated EMT, and improved the regularity of the RPE structure in vitro and in vivo. These results suggest that intravitreal TGF-ß1 injection could be used as a screening model to investigate the aging-related structural and functional changes to the RPE. Furthermore, the regulation of TGF-ß-mTORC1-NOX signaling could be a potential therapeutic target for reducing pathogenic alterations in aged RPE and AMD.


Assuntos
Alvo Mecanístico do Complexo 1 de Rapamicina/fisiologia , NADPH Oxidases/fisiologia , Epitélio Pigmentado da Retina/patologia , Fator de Crescimento Transformador beta1/fisiologia , Animais , Células Cultivadas , Senescência Celular , Transição Epitelial-Mesenquimal , Injeções Intravítreas , Degeneração Macular/tratamento farmacológico , Degeneração Macular/metabolismo , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BL , NADPH Oxidases/antagonistas & inibidores , Pirazolonas/farmacologia , Piridonas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Epitélio Pigmentado da Retina/fisiologia , Transdução de Sinais/fisiologia
8.
Int J Syst Evol Microbiol ; 72(10)2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36201336

RESUMO

Two Gram-stain-negative, aerobic, mesophilic, rod-shaped bacteria, ADR-1T and SC2-2T, were isolated from Andong sikhye and dust in a pigpen, respectively. The phylogenetic tree on the basis of 16S rRNA gene sequences showed that strains ADR-1T and SC2-2T were members of the genus Chryseobacterium and revealed the highest sequence similarities to Chryseobacterium binzhouense LM2T (97.6 %) and Chryseobacterium koreense Chj707T (94.9 %), respectively. Phylogenomic treeing using 92 core genes clearly indicated that strain ADR-1T clustered with Chryseobacterium echinoideorum CC-CZW010T, Chryseobacterium binzhouense LM2T and Chryseobacterium taihuense CGMCC 1.10941T, and strain SC2-2T formed a compact cluster with Chryseobacterium koreense CCUG 49689T. The digital DNA-DNA hybridization (dDDH) and orthologous average nucleotide identity (ANI) values of strain ADR-1T with the closely related species of the genus Chryseobacterium were ≤24.4 % and ≤80.7 %, and those of strain SC2-2T were ≤24.0 % and ≤77.8 %, respectively, which are well below the cut-off values of species discrimination (>70 % dDDH and >95-96 % ANI). The only respiratory quinone in both strains was menaquinone 6. The polar lipid profile of strain ADR-1T comprised phosphatidylethanolamine, four unidentified aminolipids and three unidentified lipids, while strain SC2-2T contained phosphatidylethanolamine, two unidentified aminolipids, one unidentified aminophospholipid and five unidentified polar lipids. The major fatty acids (>10 %) of strain ADR-1T were iso-C15 : 0, summed feature 9 (iso-C17 : 1 ω9c and/or C16 : 0 10-methyl), iso-C17 : 0 3-OH and summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), and those of strain SC2-2T were iso-C15 : 0 and anteiso-C15 : 0. On the basis of the results of phenotypic and phylogenetic analyses, strains ADR-1T and SC2-2T represent two distinct novel species in the genus Chryseobacterium, for which the names Chryseobacterium oryzae sp. nov. (type strain ADR-1T=KACC 19311T=NBRC 113104T) and Chryseobacterium suipulveris sp. nov. (type strain SC2-2T=KACC 19313T=NBRC 113106T) are proposed.


Assuntos
Chryseobacterium , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Poeira , Ácidos Graxos/química , Nucleotídeos , Fosfatidiletanolaminas , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2
9.
Fish Shellfish Immunol ; 131: 1092-1100, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36257554

RESUMO

Streptococcus parauberis, a gram-positive cocci, causes bacterial disease in farmed fish. The recent increase in S. parauberis infection in aquatic farms in South Korea has justified the importance of vaccine development for the prevention of this disease. In this study, we evaluated the effect of subunit vaccines prepared from recombinant M-like protein (SimA) and fibrinogen-binding protein (FBP) candidates with an aluminum hydroxide adjuvant against S. parauberis infection in olive flounder Paralichthys olivaceus. For the in vivo experiment, fish (average length, 7.18 cm; average weight, 3.5 g) were injected intraperitoneally with: phosphate buffer saline (PBS, group 1), PBS/aluminum hydroxide (group 2), FBP/aluminum hydroxide (group 3), SimA/aluminum hydroxide (group 4), and SimA/FBP/aluminum hydroxide (group 5). After 3 weeks, the fish in each group were boosted using PBS (group 1 and 2), FBP (group 3), SimA (group 4), and SimA/FBP (group 5) without adjuvant. We found that the relative percent survival of fish after S. parauberis exposure in group 2, 3, 4, and 5 was 6.25%, 18.75%, 50%, and 12.5%, respectively, whereas the mortality in groups 1 was 80%, respectively. We performed Western blot, ELISA, and quantitative real time RT-PCR (qRT-PCR) after vaccination to investigate the further efficacy of the vaccine. Western blot and ELISA of vaccinated fish serum confirmed the production of specific antibodies against SimA and FBP. Furthermore, results of qRT-PCR showed that recombinant protein SimA induced a remarkably specific-antibody response compared with that in FBP or control and increased the expression of various immune response-related genes including interleukin-8 (IL-8), toll-like receptor 2 (TLR2), tumor necrosis factor-α (TNF-α), CD4-1, and MHC II. Thus, these results indicate that SimA is a potent vaccine candidate for protection against S. parauberis infection.


Assuntos
Doenças dos Peixes , Linguado , Infecções Estreptocócicas , Animais , Hidróxido de Alumínio , Infecções Estreptocócicas/prevenção & controle , Infecções Estreptocócicas/veterinária , Vacinas de Subunidades Antigênicas , Adjuvantes Imunológicos/farmacologia
10.
Surg Endosc ; 36(5): 2896-2905, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34254185

RESUMO

BACKGROUND: Anastomotic leakage (AL) after gastrectomy in gastric cancer patients is associated with high mortality rates. Various endoscopic procedures are available to manage this postoperative complication. The aim of study was to evaluate the outcome of two endoscopic modalities, clippings and stents, for the treatment of AL. PATIENTS AND METHODS: There were 4916 gastric cancer patients who underwent gastrectomy between December 2007 and January 2016 at the National Cancer Center, Korea. A total of 115 patients (2.3%) developed AL. Of these, 85 patients (1.7%) received endoscopic therapy for AL and were included in this retrospective study. The endpoints were the complete leakage closure rates and risk factors associated with failure of endoscopic therapy. RESULTS: Of the 85 patients, 62 received endoscopic clippings (with or without detachable snares), and 23 received a stent insertion. Overall, the complete leakage closure rate was 80%, and no significant difference was found between the clipping and stent groups (79.0% vs. 82.6%, respectively; P = 0.89). The complete leakage closure rate was significantly lower in the duodenal and jejunal stump sites (60%) than esophageal sites (86.1%) and gastric sites (94.1%; P = 0.026). The multivariate analysis showed that stump leakage sites (adjusted odds ratio [aOR], 4.51; P = 0.031) and the presence of intra-abdominal abscess (aOR, 4.92; P = -0.025) were associated with unsuccessful leakage closures. CONCLUSIONS: Endoscopic therapy using clippings or stents is an effective method for the postoperative management of AL in gastric cancer patients. This therapy can be considered a primary treatment option due to its demonstrated efficacy, safety, and minimally invasive nature.


Assuntos
Fístula Anastomótica , Neoplasias Gástricas , Fístula Anastomótica/etiologia , Fístula Anastomótica/cirurgia , Endoscopia/efeitos adversos , Gastrectomia/efeitos adversos , Gastrectomia/métodos , Humanos , Estudos Retrospectivos , Stents/efeitos adversos , Neoplasias Gástricas/complicações , Neoplasias Gástricas/cirurgia , Resultado do Tratamento
11.
Ophthalmic Res ; 2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-35952635

RESUMO

INTRODUCTION: To evaluate the safety and efficacy of atelocollagen in preventing the fibrotic change of human tenon tissue induced by transforming growth factor ß1 (TGFß1) Methods: Primary cultured human Tenon's fibroblasts (HTFs) were incubated with TGFß1 alone, and with a various concentrations of atelocollagen respectively. Cell viability was measured by cell counting kit-8 (CCK8). The mRNA levels of α-smooth muscle actin (α-SMA), vimentin, fibronectin, zonular occludens scaffolding protein (ZO-1), cellular communication network factor 2 (CCN2) and interleukin-6 (IL-6) were measured by quantitative reverse transcription polymerase chain reaction (RT-PCR), western blot and immunofluorescence analysis. Wound healing assay and collagen contraction assay were additionally evaluated for identifying the inhibitory effect of atelocollagen in HTFs. To elucidate the mechanism by which atelocollagen affects HTFs proliferation, the phospho-extracellular-signal-regulated kinases (pERK)/total-extracellular-signal-regulated kinases (tERK), phospho-focal adhesion kinase (pFAK)/total-focal adhesion kinase (tFAK), and pSmad3/tSmad3 protein expression ratios were measured by Western blot. RESULTS: The safety of atelocollagen in HTF was identified by CCK8 analysis. The expression of α-SMA and vimentin in HTFs treated with 0.023% and 0.046% atelocollagen significantly decreased at both mRNA and protein levels, while that of ZO-1 in 0.046% atelocollagen increased compared with TGFß1-treated cells. The protein expression of fibronectin, CCN2, and IL-6 in HTFs treated with 0.023% and 0.046% atelocollagen significantly decreased. Immunofluorescence microscopy of α-SMA and ZO-1 showed results similar to those of the western blot. In the wound scratch assays, cell migration was significantly attenuated in HTFs treated with 0.005% atelocollagen. Atelocollagen at 0.005, 0.011, and 0.023% significantly inhibited the gel contraction induced by TGFß1 at both 24 h and 48 h. The increase in pERK/tERK and pSmad3/tSmad3 protein expression ratios in TGFß1-treated HTFs significantly decreased after treatment with 0.023 and 0.046% atelocollagen. CONCLUSION: Since atelocollagen gel effectively suppresses the proliferation of HTFs in TGFß1 - induced transdifferentiation, it may be a potential therapeutic agent in glaucoma surgery.

12.
Int J Mol Sci ; 23(14)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35887142

RESUMO

Lactic acid bacteria (LAB) are significant groups of probiotic organisms in fermented food and are generally considered safe. LAB regulate soil organic matter and the biochemical cycle, detoxify hazardous chemicals, and enhance plant health. They are found in decomposing plants, traditional fermented milk products, and normal human gastrointestinal and vaginal flora. Exploring LAB identified in unknown niches may lead to isolating unique species. However, their classification is quite complex, and they are adapted to high sugar concentrations and acidic environments. LAB strains are considered promising candidates for sustainable agriculture, and they promote soil health and fertility. Therefore, they have received much attention regarding sustainable agriculture. LAB metabolites promote plant growth and stimulate shoot and root growth. As fertilizers, LAB can promote biodegradation, accelerate the soil organic content, and produce organic acid and bacteriocin metabolites. However, LAB show an antagonistic effect against phytopathogens, inhibiting fungal and bacterial populations in the rhizosphere and phyllosphere. Several studies have proposed the LAB bioremediation efficiency and detoxification of heavy metals and mycotoxins. However, LAB genetic manipulation and metabolic engineered tools provide efficient cell factories tailor-made to produce beneficial industrial and agro-products. This review discusses lactic acid bacteria advantages and limitations in sustainable agricultural development.


Assuntos
Lactobacillales , Agricultura , Feminino , Fertilizantes , Humanos , Plantas , Rizosfera , Solo
13.
Blood ; 134(26): 2388-2398, 2019 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-31697804

RESUMO

The V617F mutation in the JH2 domain of Janus kinase 2 (JAK2) is an oncogenic driver in several myeloproliferative neoplasms (MPNs), including essential thrombocythemia, myelofibrosis, and polycythemia vera (PV). Other mutations in JAK2 have been identified in MPNs, most notably exon 12 mutations in PV. Here, we describe a novel recurrent mutation characterized by a common 4-amino-acid deletion and variable 1-amino-acid insertion (Leu583-Ala586DelInsSer/Gln/Pro) within the JH2 domain of JAK2. All 4 affected patients had eosinophilia, and both patients with Leu583-Ala586DelInsSer fulfilled diagnostic criteria of both PV and chronic eosinophilic leukemia (CEL). Computational and functional studies revealed that Leu583-Ala586DelInsSer (herein referred to as JAK2ex13InDel) deregulates JAK2 through a mechanism similar to JAK2V617F, activates signal transducer and activator of transcription 5 and extracellular signal-regulated kinase, and transforms parental Ba/F3 cells to growth factor independence. In contrast to JAK2V617F, JAK2ex13InDel does not require an exogenous homodimeric type 1 cytokine receptor to transform Ba/F3 cells and is capable of activating ß common chain family cytokine receptor (interleukin-3 receptor [IL-3R], IL-5R, and granulocyte-macrophage colony stimulating factor receptor) signaling in the absence of ligand, with the maximum effect observed for IL-5R, consistent with the clinical phenotype of eosinophilia. Recognizing this new PV/CEL-overlap MPN has significant clinical implications, as both PV and CEL patients are at high risk for thrombosis, and concomitant cytoreduction of red cells, neutrophils, and eosinophils may be required for prevention of thromboembolic events. Targeted next-generation sequencing for genes recurrently mutated in myeloid malignancies in patients with unexplained eosinophilia may reveal additional cases of Leu583-Ala586DelInsSer/Gln/Pro, allowing for complete characterization of this unique MPN.


Assuntos
Linfócitos B/patologia , Transformação Celular Neoplásica/patologia , Síndrome Hipereosinofílica/patologia , Mutação INDEL , Janus Quinase 2/genética , Leucemia/patologia , Policitemia Vera/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Aminoácidos , Animais , Linfócitos B/metabolismo , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Células Cultivadas , Evolução Clonal , Feminino , Humanos , Síndrome Hipereosinofílica/genética , Síndrome Hipereosinofílica/metabolismo , Janus Quinase 2/metabolismo , Leucemia/genética , Leucemia/metabolismo , Masculino , Camundongos , Oncogenes , Policitemia Vera/genética , Policitemia Vera/metabolismo
14.
Clin Endocrinol (Oxf) ; 94(3): 494-503, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32869866

RESUMO

OBJECTIVE: This study aimed to compare the diagnostic performance of core-needle biopsy (CNB) to fine-needle aspiration (FNA) as a first-line diagnostic tool in initially detected thyroid nodules, according to ultrasound (US) patterns. MATERIALS AND METHODS: This study included 778 consecutive nodules from 705 patients who underwent CNB from one institution and 627 nodules from 583 patients who underwent FNA from two institutions. Adjustments for significant differences in patients' characteristics were facilitated via propensity score matching. We compared the diagnostic performance of CNB and FNA for thyroid malignancy according to three diagnostic criteria for all nodules and the US patterns. RESULTS: A 1:1 matching of 469 patients yielded no significant differences between CNB and FNA for any covariates. CNB showed a significantly higher sensitivity for malignancy than FNA with any criterion (criterion 1: category VI, criterion 2: category V and VI, criterion 3: category IV, V and VI) in overall and high suspicion nodules (90.1-99.5% vs 69.7%-88.3%, all P-values < 0.001) and low/intermediate suspicion nodules, except criterion 1 (61.9%-100% vs 36.4%-45.5%, all P ≤ .016). In ROC curve analysis, the areas under the ROC curve of CNB were significantly higher than those for FNA with any criterion in overall and high suspicion nodules (P < .001) and in low/intermediate suspicion nodules, except criterion 1 (P ≤ .008). CNB had a slightly higher minor complication rate than FNA (0.7% vs 0%, P ≥ .069). CONCLUSION: Our study suggests that CNB has a complementary role as an alternative first-line diagnostic tool to FNA for the initial diagnosis of thyroid nodules when performed by an experienced operator.


Assuntos
Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Biópsia por Agulha Fina , Biópsia com Agulha de Grande Calibre , Humanos , Pontuação de Propensão , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/patologia
15.
Eur Radiol ; 31(7): 5041-5049, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33449180

RESUMO

OBJECTIVES: To assess the feasibility of a CNN-based liver registration algorithm to generate difference maps for visual display of spatiotemporal changes in liver PDFF, without needing manual annotations. METHODS: This retrospective exploratory study included 25 patients with suspected or confirmed NAFLD, who underwent PDFF-MRI at two time points at our institution. PDFF difference maps were generated by applying a CNN-based liver registration algorithm, then subtracting follow-up from baseline PDFF maps. The difference maps were post-processed by smoothing (5 cm2 round kernel) and applying a categorical color scale. Two fellowship-trained abdominal radiologists and one radiology resident independently reviewed difference maps to visually determine segmental PDFF change. Their visual assessment was compared with manual ROI-based measurements of each Couinaud segment and whole liver PDFF using intraclass correlation (ICC) and Bland-Altman analysis. Inter-reader agreement for visual assessment was calculated (ICC). RESULTS: The mean patient age was 49 years (12 males). Baseline and follow-up PDFF ranged from 2.0 to 35.3% and 3.5 to 32.0%, respectively. PDFF changes ranged from - 20.4 to 14.1%. ICCs against the manual reference exceeded 0.95 for each reader, except for segment 2 (2 readers ICC = 0.86-0.91) and segment 4a (reader 3 ICC = 0.94). Bland-Altman limits of agreement were within 5% across all three readers. Inter-reader agreement for visually assessed PDFF change (whole liver and segmental) was excellent (ICCs > 0.96), except for segment 2 (ICC = 0.93). CONCLUSIONS: Visual assessment of liver segmental PDFF changes using a CNN-generated difference map strongly agreed with manual estimates performed by an expert reader and yielded high inter-reader agreement. KEY POINTS: • Visual assessment of longitudinal changes in quantitative liver MRI can be performed using a CNN-generated difference map and yields strong agreement with manual estimates performed by expert readers.


Assuntos
Interpretação de Imagem Assistida por Computador , Hepatopatia Gordurosa não Alcoólica , Humanos , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Estudos Retrospectivos
16.
Eur Radiol ; 31(10): 7594-7604, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33876298

RESUMO

OBJECTIVES: According to LI-RADS, a major discriminating feature between hepatocellular carcinoma (HCC) and non-HCC malignancies is the subtype of arterial phase hyperenhancement (APHE). The aim of this study was to investigate whether APHE subtypes are consistent across multi-arterial phase (mHAP) MRI acquisitions while evaluating reader agreement. Secondarily, we investigated factors that may affect reader agreement for APHE subtype. METHODS: In this retrospective study, consecutive patients with liver cirrhosis and focal observations who underwent mHAP were included. Five radiologists reviewed MR images in 2 reading sessions. In reading session 1, individual AP series were reviewed and scored for presence of APHE and subtype. In reading session 2, readers scored observations' major and ancillary features and LI-RADS category in the complete MRI examination. Reader agreement was calculated using Fleiss' kappa for binary outcomes and Kendall's coefficient of concordance for LI-RADS categories. Univariate mixed effects logistic regressions were performed to investigate factors affecting agreement. RESULTS: In total, 61 patients with 77 focal observations were analyzed. Of observations unanimously scored as having APHE, 27.7% showed both rim and nonrim subtypes on mHAP. Inter-reader agreement for APHE subtype ranged from 0.49 (95% CI: 0.33, 0.64) to 0.57 (95% CI: 0.40, 0.74) between reading sessions. Observation size had a trend level effect on rim APHE agreement (p = 0.052). CONCLUSION: Approximately 1/3 of observations demonstrated inconsistent APHE subtype during mHAP acquisition. Small lesions were particularly challenging. Further guidance on APHE subtype classification, especially when applied to mHAP, could be a focus of LI-RADS refinement. KEY POINTS: • In a cohort of patients at risk for HCC, 28% of the observations showed inconsistent arterial phase hyperenhancement (APHE) subtypes (rim and nonrim) on multi-arterial phase imaging according to the majority score of 5 independent readers. • Inconsistent APHE subtypes may challenge reliable imaging diagnosis, i.e., LI-RADS categorization, of focal liver observations in patients at risk for HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagem , Meios de Contraste , Humanos , Fígado , Neoplasias Hepáticas/diagnóstico por imagem , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Sensibilidade e Especificidade
17.
Health Qual Life Outcomes ; 19(1): 242, 2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34656119

RESUMO

BACKGROUND: Ticagrelor has a Class I recommendation for use following percutaneous coronary intervention (PCI) in acute coronary syndrome (ACS). However, ticagrelor needs to be taken twice a day, as compared to clopidogrel. Its adverse effects, such as dyspnea or bleeding, are known to be more common than with clopidogrel. Dyspnea may tend to be uncomfortable and limit activity. Major bleeding often leads to hospitalization or transfusions, and frequent minor bleeding, which might not result in patients seeking medical care, can make ACS patients feel unhealthy. Thus, these characteristics may affect the health-related quality of life (HQOL). METHODS: In the PLEIO (comParison of ticagreLor and clopidogrEl on mIcrocirculation in patients with acute cOronary syndrome) trial, we randomized 120 participants to receive ticagrelor 90 mg twice daily or clopidogrel 75 mg once daily for at least 12 months. We carried out an HQOL assessment with the Short Form 36 Health Survey (SF-36) questionnaire on the day of discharge following PCI, as well as six months later. RESULTS: At discharge, the HQOL measures were similar in the ticagrelor and clopidogrel groups, both having a physical component summary (PCS) and a mental component summary (MCS) score. A six-month HQOL follow-up assessment showed that there were no differences between the two study groups in either the PCS or the MCS scores. In both groups, the PCS scores significantly increased over six months of treatment (both p < 0.01). However, the MCS score did not differ significantly. A baseline MCS score is an independent predictor of better physical and mental health status at six months. CONCLUSIONS: Ticagrelor, as compared to clopidogrel, did not significantly reduce the HQOL during the six months following PCI in patients with ACS. Clinical Trial Registration URL: http://www.clinicaltrials.gov . Unique identifier: NCT02618733.


Assuntos
Síndrome Coronariana Aguda , Intervenção Coronária Percutânea , Síndrome Coronariana Aguda/tratamento farmacológico , Clopidogrel/uso terapêutico , Humanos , Inibidores da Agregação Plaquetária/efeitos adversos , Qualidade de Vida , Ticagrelor/uso terapêutico , Resultado do Tratamento
18.
Plant J ; 99(3): 452-464, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30943325

RESUMO

During the transition to the reproductive phase, the shoot apical meristem switches from the developmental program that generates vegetative organs to instead produce flowers. In this study, we examined the genetic interactions of FLOWERING LOCUS T (FT)/TWIN SISTER OF FT (TSF) and TERMINAL FLOWER 1 (TFL1) in the determination of inflorescence meristem identity in Arabidopsis thaliana. The ft-10 tsf-1 mutants produced a compact inflorescence surrounded by serrated leaves (hyper-vegetative shoot) at the early bolting stage, as did plants overexpressing TFL1. Plants overexpressing FT or TSF (or both FT and TFL1) generated a terminal flower, as did tfl1-20 mutants. The terminal flower formed in tfl1-20 mutants converted to a hyper-vegetative shoot in ft-10 tsf-1 mutants. Grafting ft-10 tsf-1 or ft-10 tsf-1 tfl1-20 mutant scions to 35S::FT rootstock plants produced a normal inflorescence and a terminal flower in the scion plants, respectively, although both scions showed similar early flowering. Misexpression of FT in the vasculature and in the shoot apex in wild-type plants generated a normal inflorescence and a terminal flower, respectively. By contrast, in ft-10 tsf-1 mutants the vasculature-specific misexpression of FT converted the hyper-vegetative shoot to a normal inflorescence, and in the ft-10 tsf-1 tfl1-20 mutants converted the shoot to a terminal flower. TFL1 levels did not affect the inflorescence morphology caused by FT/TSF overexpression at the early bolting stage. Taking these results together, we proposed that FT/TSF and TFL1 play antagonistic roles in the determination of inflorescence meristem identity, and that FT/TSF are more important than TFL1 in this process.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Inflorescência/genética , Meristema/genética , Proteína de Ligação a Fosfatidiletanolamina/genética , Arabidopsis/anatomia & histologia , Arabidopsis/crescimento & desenvolvimento , Epistasia Genética , Flores/anatomia & histologia , Flores/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Inflorescência/anatomia & histologia , Inflorescência/crescimento & desenvolvimento , Meristema/anatomia & histologia , Meristema/crescimento & desenvolvimento , Mutação , Fenótipo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Plantas Geneticamente Modificadas
19.
Biochem Biophys Res Commun ; 522(1): 240-246, 2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-31759628

RESUMO

Fenestrations in choriocapillaris act as a window for molecular transports between the retina and choroid, and is crucial for maintaining visual function. Plasmalemma vesicle-associated protein (PLVAP) is essential for the development of endothelial fenestrations. There is little knowledge about how the choriocapillaris maintains the fenestrated endothelium. This study aimed to evaluate the role of vascular endothelial growth factor-A (VEGFA)-PLVAP axis in the maintenance of choroidal fenestrations using oxygen-induced retinopathy (OIR) model. In C57BL/6 J mice, the mice with OIR on postnatal day 12 (P12) presented thicker endothelium and less fenestration compared to the non-OIR mice. However, the OIR on 17 mice showed thinner endothelium with more fenestration compared to OIR on P12. In vivo angiography demonstrated the presence of hyperpermeable choroidal vessels on P17 in OIR mice. These dramatic changes in choriocapillaris were not observed in the BALB/cJ OIR model. The ultrastructural changes in the choriocapillaris were correlated with temporal variations in the expression of VEGFA and PLVAP. VEGFA stimulated expression of PLVAP in the choroidal endothelial cells. Loss of PLVAP disrupts the polarized structure of the choriocapillaris leading to retinal degeneration. These results indicate that the expression of retinal VEGFA is essential for maintaining the structure and function of choriocapillaris by preserving the endothelial PLVAP.


Assuntos
Corioide/metabolismo , Proteínas de Membrana/metabolismo , Retina/metabolismo , Doenças Retinianas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Células Cultivadas , Corioide/patologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Humanos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Oxigênio/metabolismo , Retina/patologia , Doenças Retinianas/patologia
20.
Biochem Biophys Res Commun ; 529(3): 747-752, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32736702

RESUMO

Transforming growth factor-ß (TGF-ß) plays a crucial role in the development of epithelial to mesenchymal transition (EMT) and fibrosis, particularly in an ocular disorder such as proliferative vitreoretinopathy (PVR). However, the key molecular mechanism underlying its pathogenesis remains unknown. In the present study, using cultured ARPE-19 cells, we determined that TGF-ß initiates a signaling pathway through extracellular signal-regulated kinase (ERK)-mammalian target of rapamycin complex 1 (mTORC1) that stimulates trans-differentiation and fibrosis of retinal pigment epithelium. Blocking this pathway by a TGF-ßRI, ERK or mTORC1 inhibitor protected cells from EMT and fibrotic protein expression. TGF-ß1 treatment increased reactive oxygen species (ROS) via NOX4 upregulation, which acts downstream of ERK and mTORC1, as the ROS scavenger N-acetylcysteine and a pan-NADPH oxidase (NOX) inhibitor DPI dissipated excess ROS generation. TGF-ß1-induced oxidative stress resulted in EMT and fibrotic changes, as NAC and DPI prevented α-SMA, Col4α3 expression and cell migration. All these inhibitors blocked the downstream pathway activation in addition to clearly preventing the activation of its upstream molecules, indicating the presence of a feedback loop system that may boost the upstream events. Furthermore, the FDA-approved drug trametinib (10 nM) blunted TGF-ß1-induced mTORC1 activation and downstream pathogenic alterations through ERK1/2 inhibition, which opens a therapeutic avenue for the treatment of PVR in the future.


Assuntos
Transição Epitelial-Mesenquimal , Sistema de Sinalização das MAP Quinases , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , NADPH Oxidase 4/metabolismo , Epitélio Pigmentado da Retina/patologia , Fator de Crescimento Transformador beta1/metabolismo , Linhagem Celular , Ativação Enzimática , Fibrose , Humanos , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/metabolismo , Transdução de Sinais
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