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1.
Nat Immunol ; 21(12): 1611, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32681143

RESUMEN

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

2.
Cell ; 165(3): 551-65, 2016 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-27040498

RESUMEN

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by loss of tolerance to nucleic acids and highly diverse clinical manifestations. To assess its molecular heterogeneity, we longitudinally profiled the blood transcriptome of 158 pediatric patients. Using mixed models accounting for repeated measurements, demographics, treatment, disease activity (DA), and nephritis class, we confirmed a prevalent IFN signature and identified a plasmablast signature as the most robust biomarker of DA. We detected gradual enrichment of neutrophil transcripts during progression to active nephritis and distinct signatures in response to treatment in different nephritis subclasses. Importantly, personalized immunomonitoring uncovered individual correlates of disease activity that enabled patient stratification into seven groups, supported by patient genotypes. Our study uncovers the molecular heterogeneity of SLE and provides an explanation for the failure of clinical trials. This approach may improve trial design and implementation of tailored therapies in genetically and clinically complex autoimmune diseases. PAPERCLIP.


Asunto(s)
Lupus Eritematoso Sistémico/genética , Adolescente , Niño , Femenino , Humanos , Estudios Longitudinales , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/patología , Lupus Eritematoso Sistémico/terapia , Nefritis Lúpica/genética , Nefritis Lúpica/inmunología , Neutrófilos/inmunología , Polimorfismo de Nucleótido Simple , Medicina de Precisión , Transcriptoma
3.
Nat Immunol ; 17(12): 1373-1380, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27695001

RESUMEN

The respiratory tract is heavily populated with innate immune cells, but the mechanisms that control such cells are poorly defined. Here we found that the E3 ubiquitin ligase TRIM29 was a selective regulator of the activation of alveolar macrophages, the expression of type I interferons and the production of proinflammatory cytokines in the lungs. We found that deletion of TRIM29 enhanced macrophage production of type I interferons and protected mice from infection with influenza virus, while challenge of Trim29-/- mice with Haemophilus influenzae resulted in lethal lung inflammation due to massive production of proinflammatory cytokines by macrophages. Mechanistically, we demonstrated that TRIM29 inhibited interferon-regulatory factors and signaling via the transcription factor NF-κB by degrading the adaptor NEMO and that TRIM29 directly bound NEMO and subsequently induced its ubiquitination and proteolytic degradation. These data identify TRIM29 as a key negative regulator of alveolar macrophages and might have important clinical implications for local immunity and immunopathology.


Asunto(s)
Infecciones por Haemophilus/inmunología , Haemophilus influenzae/inmunología , Virus de la Influenza A/inmunología , Macrófagos/inmunología , Infecciones por Orthomyxoviridae/inmunología , Sistema Respiratorio/inmunología , Factores de Transcripción/metabolismo , Animales , Células Cultivadas , Inmunidad Innata , Interferón Tipo I/genética , Interferón Tipo I/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Macrófagos/microbiología , Macrófagos/virología , Ratones , Ratones Noqueados , FN-kappa B/metabolismo , Proteolisis , Transducción de Señal , Factores de Transcripción/genética , Ubiquitinación
4.
Nat Immunol ; 17(6): 646-55, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27111142

RESUMEN

Group 2 innate lymphoid cells (ILC2 cells) are important for type 2 immune responses and are activated by the epithelial cytokines interleukin 33 (IL-33), IL-25 and thymic stromal lymphopoietin (TSLP). Here we demonstrated that IL-1ß was a critical activator of ILC2 cells, inducing proliferation and cytokine production and regulating the expression of epithelial cytokine receptors. IL-1ß also governed ILC2 plasticity by inducing low expression of the transcription factor T-bet and the cytokine receptor chain IL-12Rß2, which enabled the conversion of these cells into an ILC1 phenotype in response to IL-12. This transition was marked by an atypical chromatin landscape characterized by the simultaneous transcriptional accessibility of the locus encoding interferon-γ (IFN-γ) and the loci encoding IL-5 and IL-13. Finally, IL-1ß potentiated ILC2 activation and plasticity in vivo, and IL-12 acted as the switch that determined an ILC2-versus-ILC1 response. Thus, we have identified a previously unknown role for IL-1ß in facilitating ILC2 maturation and plasticity.


Asunto(s)
Plasticidad de la Célula , Inmunidad Innata , Interleucina-12/metabolismo , Interleucina-1beta/metabolismo , Linfocitos/inmunología , Animales , Diferenciación Celular , Plasticidad de la Célula/inmunología , Células Cultivadas , Citocinas/metabolismo , Humanos , Interferón gamma/metabolismo , Interleucina-17/metabolismo , Interleucina-33/metabolismo , Ratones , Ratones SCID , Receptores de Interleucina-12/genética , Receptores de Interleucina-12/metabolismo , Transducción de Señal , Proteínas de Dominio T Box/genética , Proteínas de Dominio T Box/metabolismo , Células TH1/inmunología , Balance Th1 - Th2 , Células Th2/inmunología , Linfopoyetina del Estroma Tímico
6.
Nat Immunol ; 16(9): 970-9, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26168081

RESUMEN

Interleukin 17-producing helper T cells (T(H)17 cells) have a major role in protection against infections and in mediating autoimmune diseases, yet the mechanisms involved are incompletely understood. We found that interleukin 26 (IL-26), a human T(H)17 cell-derived cytokine, is a cationic amphipathic protein that kills extracellular bacteria via membrane-pore formation. Furthermore, T(H)17 cell-derived IL-26 formed complexes with bacterial DNA and self-DNA released by dying bacteria and host cells. The resulting IL-26-DNA complexes triggered the production of type I interferon by plasmacytoid dendritic cells via activation of Toll-like receptor 9, but independently of the IL-26 receptor. These findings provide insights into the potent antimicrobial and proinflammatory function of T(H)17 cells by showing that IL-26 is a natural human antimicrobial that promotes immune sensing of bacterial and host cell death.


Asunto(s)
ADN Bacteriano/inmunología , ADN/inmunología , Inmunidad Innata/inmunología , Interleucinas/inmunología , Células Th17/inmunología , Receptor Toll-Like 9/inmunología , Animales , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Humanos , Interferón Tipo I/inmunología , Interferón Tipo I/metabolismo , Ratones , Psoriasis/inmunología , Receptores de Interleucina/inmunología , Receptores de Interleucina/metabolismo
7.
PLoS Pathog ; 20(7): e1012379, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39037956

RESUMEN

RNA helicases are involved in the innate immune response against pathogens, including bacteria and viruses; however, their mechanism in the human airway epithelial cells is still not fully understood. Here, we demonstrated that DEAH (Asp-Glu-Ala-His) box polypeptide 35 (DHX35), a member of the DExD/H (Asp-Glu-x-Asp/His)-box helicase family, boosts antiviral innate immunity in human airway epithelial cells. DHX35 knockdown attenuated the production of interferon-ß (IFN-ß), IL6, and CXCL10, whereas DHX35 overexpression increased their production. Upon stimulation, DHX35 was constitutively expressed, but it translocated from the nucleus into the cytosol, where it recognized cytosolic poly(I:C) and poly(dA:dT) via its HELICc domain. Mitochondrial antiviral signaling protein (MAVS) acted as an adaptor for DHX35 and interacted with the HELICc domain of DHX35 using amino acids 360-510. Interestingly, DHX35 interacted with retinoic acid-inducible gene 1 (RIG-I), enhanced the binding affinity of RIG-I with poly(I:C) and poly(dA:dT), and formed a signalsome with MAVS to activate interferon regulatory factor 3 (IRF3), NF-κB-p65, and MAPK signaling pathways. These results indicate that DHX35 not only acted as a cytosolic nucleic acid sensor but also synergized with RIG-I to enhance antiviral immunity in human airway epithelial cells. Our results demonstrate a novel molecular mechanism for DHX35 in RIG-I-mediated innate immunity and provide a novel candidate for drug and vaccine design to control viral infections in the human airway.


Asunto(s)
Proteína 58 DEAD Box , ARN Helicasas DEAD-box , Inmunidad Innata , Receptores Inmunológicos , Humanos , Proteína 58 DEAD Box/metabolismo , Proteína 58 DEAD Box/inmunología , ARN Helicasas DEAD-box/metabolismo , ARN Helicasas DEAD-box/inmunología , Receptores Inmunológicos/metabolismo , Poli I-C/inmunología , Poli I-C/farmacología , ARN Helicasas/metabolismo , ARN Helicasas/inmunología , Transducción de Señal/inmunología , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/inmunología , Células Epiteliales/inmunología , Células Epiteliales/metabolismo , Células Epiteliales/virología , Células HEK293
9.
J Biol Chem ; 300(7): 107463, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38876304

RESUMEN

Chemotherapeutic agents for treating colorectal cancer (CRC) primarily induce apoptosis in tumor cells. The ubiquitin-proteasome system is critical for apoptosis regulation. Deubiquitinating enzymes (DUBs) remove ubiquitin from substrates to reverse ubiquitination. Although over 100 DUB members have been discovered, the biological functions of only a small proportion of DUBs have been characterized. Here, we aimed to systematically identify the DUBs that contribute to the development of CRC. Among the DUBs, ubiquitin-specific protease 36 (USP36) is upregulated in CRC. We showed that the knockdown of USP36 induces intrinsic and extrinsic apoptosis. Through gene silencing and coimmunoprecipitation techniques, we identified survivin and cIAP1 as USP36 targets. Mechanistically, USP36 binds and removes lysine-11-linked ubiquitin chains from cIAP1 and lysine-48-linked ubiquitin chains from survivin to abolish protein degradation. Overexpression of USP36 disrupts the formation of the XIAP-second mitochondria-derived activator of caspase complex and promotes receptor-interacting protein kinase 1 ubiquitination, validating USP36 as an inhibitor to intrinsic and extrinsic apoptosis through deubiquitinating survivin and cIAP1. Therefore, our results suggest that USP36 is involved in CRC progression and is a potential therapeutic target.


Asunto(s)
Apoptosis , Neoplasias Colorrectales , Proteínas Inhibidoras de la Apoptosis , Survivin , Ubiquitina Tiolesterasa , Ubiquitinación , Humanos , Línea Celular Tumoral , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/genética , Regulación Neoplásica de la Expresión Génica , Proteínas Inhibidoras de la Apoptosis/metabolismo , Proteínas Inhibidoras de la Apoptosis/genética , Survivin/metabolismo , Survivin/genética , Ubiquitina Tiolesterasa/metabolismo , Ubiquitina Tiolesterasa/genética
10.
Nat Immunol ; 14(2): 172-8, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23222971

RESUMEN

DDX41 is a sensor of intracellular double-stranded DNA (dsDNA) in myeloid dendritic cells (mDCs) that triggers a type I interferon response via the signaling adaptor STING. We identified the E3 ligase TRIM21 as a DDX41-interacting protein and found that knockdown of or deficiency in TRIM21 resulted in enhanced type I interferon responses to intracellular dsDNA and DNA viruses. Overexpression of TRIM21 resulted in more degradation of DDX41 and less production of interferon-ß (IFN-ß) in response to intracellular dsDNA. The SPRY-PRY domain of TRIM21 interacted with the DEADc domain of DDX41. Lys9 and Lys115 of DDX41 were the targets of TRIM21-mediated ubiquitination. TRIM21 is therefore an interferon-inducible E3 ligase that induces the Lys48 (K48)-linked ubiquitination and degradation of DDX41 and negatively regulates the innate immune response to intracellular dsDNA.


Asunto(s)
ADN Viral/inmunología , ADN/inmunología , Células Dendríticas/inmunología , Inmunidad Innata , Ribonucleoproteínas/inmunología , Animales , ADN/genética , ADN Viral/genética , Células Dendríticas/patología , Células Dendríticas/virología , Regulación de la Expresión Génica , Interferón beta/biosíntesis , Interferón beta/inmunología , Lisina/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/inmunología , Ratones , Ratones Transgénicos , Orthoreovirus de los Mamíferos/fisiología , Estructura Terciaria de Proteína , Proteolisis , Ribonucleoproteínas/deficiencia , Ribonucleoproteínas/genética , Transducción de Señal/inmunología , Ubiquitinación , Vesiculovirus/fisiología
11.
J Am Chem Soc ; 146(29): 19962-19973, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38985576

RESUMEN

Installing fluorine atoms onto natural products holds great promise for the generation of fluorinated molecules with improved or novel pharmacological properties. The enzymatic oxidative carbon-carbon coupling reaction represents a straightforward strategy for synthesizing biaryl architectures, but the exploration of this method for producing fluorine-substituted derivatives of natural products remains elusive. Here, in this study, we report the protein engineering of cytochrome P450 from Mycobacterium tuberculosis (MtCYP121) for the construction of a series of new-to-nature fluorine-substituted Mycocyclosin derivatives. This protocol takes advantage of a "hybrid" chemoenzymatic procedure consisting of tyrosine phenol lyase-catalyzed fluorotyrosine preparation from commercially available fluorophenols, intermolecular chemical condensation to give cyclodityrosines, and an engineered MtCYP121-catalyzed intramolecular biphenol coupling reaction to complete the strained macrocyclic structure. Computational mechanistic studies reveal that MtCYP121 employs Cpd I to abstract a hydrogen atom from the proximal phenolic hydroxyl group of the substrate to trigger the reaction. Then, conformational change makes the two phenolic hydroxyl groups close enough to undergo intramolecular hydrogen atom transfer with the assistance of a pocket water molecule. The final diradical coupling process completes the intramolecular C-C bond formation. The efficiency of the biaryl coupling reaction was found to be influenced by various fluorine substitutions, primarily due to the presence of distinct binding conformations.


Asunto(s)
Sistema Enzimático del Citocromo P-450 , Mycobacterium tuberculosis , Ingeniería de Proteínas , Sistema Enzimático del Citocromo P-450/metabolismo , Sistema Enzimático del Citocromo P-450/química , Mycobacterium tuberculosis/enzimología , Biocatálisis , Halogenación , Estructura Molecular
12.
J Am Chem Soc ; 146(8): 5461-5469, 2024 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-38355136

RESUMEN

Two-dimensional (2D) DNA origami assembly represents a powerful approach to the programmable design and construction of advanced 2D materials. Within the context of hybridization-mediated 2D DNA origami assembly, DNA spacers play a pivotal role as essential connectors between sticky-end regions and DNA origami units. Here, we demonstrated that programming the spacer length, which determines the binding radius of DNA origami units, could effectively tune sticky-end hybridization reactions to produce distinct 2D DNA origami arrays. Using DNA-PAINT super-resolution imaging, we unveiled the significant impact of spacer length on the hybridization efficiency of sticky ends for assembling square DNA origami (SDO) units. We also found that the assembly efficiency and pattern diversity of 2D DNA origami assemblies were critically dependent on the spacer length. Remarkably, we realized a near-unity yield of ∼98% for the assembly of SDO trimers and tetramers via this spacer-programmed strategy. At last, we revealed that spacer lengths and thermodynamic fluctuations of SDO are positively correlated, using molecular dynamics simulations. Our study thus paves the way for the precision assembly of DNA nanostructures toward higher complexity.


Asunto(s)
ADN , Nanoestructuras , ADN Intergénico , Conformación de Ácido Nucleico , ADN/química , Nanoestructuras/química , Hibridación de Ácido Nucleico , Nanotecnología
13.
Anal Chem ; 96(6): 2341-2350, 2024 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-38300877

RESUMEN

Multiplex assay has emerged as a robust and versatile method for the simultaneous detection of multiple analytes in a single test. However, challenges in terms of poor accuracy and complexity remained. In this work, we developed a multiplex aptamer-based fluorescence assay using magnetism-encoded nanoparticles for the simultaneous detection of multiple pathogenic bacteria. The encapsulation of different amounts of Fe3O4 nanoparticles in zeolitic imidazolate framework-90 (ZIF-90) leads to the formation of Fe3O4@ZIF-90 (FZ) composites with distinct magnetism strengths. By functionalizing a specific aptamer on the surface of the FZ composites, target bacteria can be specifically and precisely separated from a mixed sample in a sequential manner. This property allows for the simultaneous quantitative analysis of multiple target bacteria by using a single-color fluorescence label, thereby resulting in minimal spectral crosstalk interference and improved accuracy. The successful determination of multiple bacteria in contaminated milk samples demonstrates the applicability of this multiplex assay in complex biological matrices. Compared to conventional multiplex fluorescence assays, this approach offers distinct advantages of simplicity, efficiency, and implementation. We believe that this study can provide valuable insights into the development of the multiplex assay while introducing a new method for the simultaneous detection of multiple bacteria.


Asunto(s)
Aptámeros de Nucleótidos , Estructuras Metalorgánicas , Nanopartículas , Límite de Detección , Bacterias
14.
Mod Pathol ; 37(9): 100543, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38897453

RESUMEN

Gastrointestinal (GI) tract involvement by Langerhans cell histiocytosis (LCH) is rare and its clinicopathologic characteristics have only been described in case reports and small series. We reviewed hematoxylin and eosin and CD1a, S100, and Langerin immunohistochemical-stained slides from 47 patients with well-documented demographic and clinical findings. Our cases included 8 children and 39 adults, with a mean follow-up of 63 months. All pediatric patients had concurrent multisystem LCH, presented with GI symptoms, and showed nonpolypoid lesions. Seven (88%) showed multifocal GI disease, including 5 with multiple GI organ involvement. All sampled lesions from children exhibited infiltrative growth. More than half had died of the disease or manifested persistent LCH at last follow-up. Twenty-five of 39 (64%) adults had LCH involving only the GI tract (single system), with the remaining 14 (36%) exhibiting multisystem disease. Adult single-system GI LCH was typically encountered incidentally on screening/surveillance endoscopy (72%). Most exhibited isolated colorectal involvement (88%) as a solitary polyp (92%), with a well-demarcated/noninfiltrative growth pattern (70%), and excellent prognosis (100%). In comparison, adult patients with multisystem LCH more frequently presented with GI symptoms (92%, P < .001), noncolorectal GI site involvement (50%, P = .02), multifocal GI lesions (43%, P = .005), nonpolypoid lesions (71%, P < .001), infiltrative histologic growth pattern (78%, P = .04), and persistent disease (57%, P < .001). Adult patients with multisystem LCH appear to exhibit similar clinicopathologic features to those of pediatric patients. These results demonstrated that adults with single-system LCH involving the GI tract have an excellent prognosis, whereas multisystem LCH occurring at any age carries an unfavorable prognosis. High-risk features of GI LCH include pediatric age, GI symptomatology, noncolorectal GI involvement, multifocal GI disease, nonpolypoid lesions, and infiltrative growth pattern.


Asunto(s)
Enfermedades Gastrointestinales , Histiocitosis de Células de Langerhans , Humanos , Histiocitosis de Células de Langerhans/patología , Masculino , Femenino , Niño , Preescolar , Adolescente , Adulto , Enfermedades Gastrointestinales/patología , Persona de Mediana Edad , Lactante , Adulto Joven , Anciano , Inmunohistoquímica
15.
Nat Immunol ; 13(12): 1155-61, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23142775

RESUMEN

The induction of type I interferons by the bacterial secondary messengers cyclic di-GMP (c-di-GMP) or cyclic di-AMP (c-di-AMP) is dependent on a signaling axis that involves the adaptor STING, the kinase TBK1 and the transcription factor IRF3. Here we identified the heliase DDX41 as a pattern-recognition receptor (PRR) that sensed both c-di-GMP and c-di-AMP. DDX41 specifically and directly interacted with c-di-GMP. Knockdown of DDX41 via short hairpin RNA in mouse or human cells inhibited the induction of genes encoding molecules involved in the innate immune response and resulted in defective activation of STING, TBK1 and IRF3 in response to c-di-GMP or c-di-AMP. Our results suggest a mechanism whereby c-di-GMP and c-di-AMP are detected by DDX41, which forms a complex with STING to signal to TBK1-IRF3 and activate the interferon response.


Asunto(s)
GMP Cíclico/análogos & derivados , ARN Helicasas DEAD-box/metabolismo , Fosfatos de Dinucleósidos/metabolismo , Interferón Tipo I/inmunología , Listeria monocytogenes/inmunología , Listeria monocytogenes/metabolismo , Receptores de Reconocimiento de Patrones/metabolismo , Animales , Línea Celular , GMP Cíclico/metabolismo , ARN Helicasas DEAD-box/genética , Humanos , Inmunidad Innata , Factor 3 Regulador del Interferón/metabolismo , Macrófagos/inmunología , Proteínas de la Membrana/metabolismo , Ratones , Proteínas Serina-Treonina Quinasas/metabolismo , Interferencia de ARN , ARN Interferente Pequeño , Receptores de Reconocimiento de Patrones/genética , Sistemas de Mensajero Secundario , Transducción de Señal
16.
New Phytol ; 242(4): 1798-1813, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38155454

RESUMEN

It is well understood that agricultural management influences arbuscular mycorrhizal (AM) fungi, but there is controversy about whether farmers should manage for AM symbiosis. We assessed AM fungal communities colonizing wheat roots for three consecutive years in a long-term (> 14 yr) tillage and fertilization experiment. Relationships among mycorrhizas, crop performance, and soil ecosystem functions were quantified. Tillage, fertilizers and continuous monoculture all reduced AM fungal richness and shifted community composition toward dominance of a few ruderal taxa. Rhizophagus and Dominikia were depressed by tillage and/or fertilization, and their abundances as well as AM fungal richness correlated positively with soil aggregate stability and nutrient cycling functions across all or no-tilled samples. In the field, wheat yield was unrelated to AM fungal abundance and correlated negatively with AM fungal richness. In a complementary glasshouse study, wheat biomass was enhanced by soil inoculum from unfertilized, no-till plots while neutral to depressed growth was observed in wheat inoculated with soils from fertilized and conventionally tilled plots. This study demonstrates contrasting impacts of low-input and conventional agricultural practices on AM symbiosis and highlights the importance of considering both crop yield and soil ecosystem functions when managing mycorrhizas for more sustainable agroecosystems.


Asunto(s)
Productos Agrícolas , Ecosistema , Fertilizantes , Micorrizas , Microbiología del Suelo , Suelo , Triticum , Micorrizas/fisiología , Suelo/química , Triticum/microbiología , Triticum/crecimiento & desarrollo , Triticum/fisiología , Productos Agrícolas/microbiología , Productos Agrícolas/crecimiento & desarrollo , Agricultura/métodos , Biomasa , Raíces de Plantas/microbiología , Factores de Tiempo , Biodiversidad
17.
Histopathology ; 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39267205

RESUMEN

AIMS: Neuroendocrine tumours (NETs) occurring in the extrahepatic biliary system are exceedingly rare. While NETs typically manifest as mass lesions, the occurrence of microscopic neuroendocrine cell proliferation without a distinct mass remains undocumented at this location. This study aims to characterise the clinicopathological features of a series of well-differentiated neuroendocrine lesions involving the extrahepatic biliary tree, including mass forming NETs and microscopic non-mass-forming neuroendocrine cell proliferation, designated neuroendocrine cell micronests (NCMs). METHODS AND RESULTS: Surgical resections of NETs/NCMs involving the extrahepatic bile ducts and gallbladder were identified from electronic pathology databases among seven institutions spanning from January 2011 to September 2023. Clinical and histological findings were recorded. Ten patients (four female, six male: age range = 34-75 years) were included in the study. Histopathological examination revealed visible mass-forming lesions in four cases (1.6-14.0 cm in size), identified in the gallbladder (n = two) or extrahepatic bile duct (n = two), all diagnosed as well-differentiated NETs. The remaining six cases revealed incidental non-mass-forming NCMs in either the cystic duct (n = two), common bile duct (n = three) or gallbladder (n = one), ranging from < 0.1 to 0.4 cm; four were associated with biliary lithiasis. No evidence of metastasis or recurrence was seen in the follow-up period (range = 0.1-11.2 years). CONCLUSIONS: This study highlights the spectrum of extrahepatic biliary well-differentiated neuroendocrine lesions, ranging from incidental microscopic NCMs to grossly apparent mass-forming NETs, potentially requiring different clinical management. Noteworthy is the frequent association of incidental microscopic neuroendocrine cell proliferations with biliary lithiasis, indicating a potential neuroendocrine metaplastic pathogenesis that merits further exploration.

18.
Opt Lett ; 49(20): 5695-5698, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39404515

RESUMEN

In this study, a new methodology, in which the cation and chiral agent are doped in positive and negative nematic liquid crystal mixture to form cation-doped positive-negative chiral nematic liquid crystals (PN-CNLCs), is proposed. These PN-CNLCs are capable of achieving a wide wavelength tuning range close to 90 nm under the action of a high-frequency electric field. The dielectric interaction between these two liquid crystals with different dielectric anisotropies in the electric field allows for the effective change of the pitch of the CLCs. We discovered the tilting of the pitch in the PN-CNLCs by a series of well-designed validation experiments. The experimental results prove the symmetrical helix is formed along the alignment direction in PN-CNLCs. Furthermore, the experiments demonstrated that an increase in voltage does not directly affect the pitch, but it increases the tilt angle of the helix axis with respect to the normal of the LC cell. This study offers, to our knowledge, a novel perspective on the tuning performance of CLCs under electric field conditions, by integrating the properties of positive and negative liquid crystals. This finding not only contributes to the understanding of the electric field response mechanism of CLCs but also provides new avenues for the application of CLCs in fields such as wavelength tuning.

19.
Haematologica ; 109(7): 2144-2156, 2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38328859

RESUMEN

Hematopoietic stem cells (HSC) are primarily dormant in a cell-cycle quiescence state to preserve their self-renewal capacity and long-term maintenance. How HSC maintain the balance between activation and quiescence remains largely unknown. Herein, we found that phosphatase, Mg2+/Mn2+ dependent 1B (Ppm1b) is required for the expansion of phenotypic HSC in vitro. By using a conditional knockout mouse model in which Ppm1b was specifically depleted in hematopoietic cells, we demonstrated that loss of Ppm1b impaired the HSC homeostasis and hematopoietic reconstitution. Ppm1b deficiency mice also exhibited B-cell leukocytopenia, which is due to the compromised commitment and proliferation of B-biased lymphoid progenitor cells from common lymphoid progenitors. With the aid of a small molecular inhibitor, we confirmed the roles of Ppm1b in adult hematopoiesis that phenocopied the effects with loss of Ppm1b. Furthermore, transcriptome profiling of Ppm1b-deficient HSC revealed the disruptive quiescence of HSC. Mechanistically, Ppm1b interacted with ß-catenin and mediated its dephosphorylation. Loss of Ppm1b led to the decrease in the active ß-catenin (non-phosphorylated) that interrupted the Wnt/ß-catenin signaling in HSC, which consequently suppressed HSC expansion. Together, our study identified an indispensable role for Ppm1b in regulating HSC homeostasis via the Wnt/ß-catenin pathway.


Asunto(s)
Células Madre Hematopoyéticas , Homeostasis , Ratones Noqueados , Proteína Fosfatasa 2C , Vía de Señalización Wnt , Animales , Células Madre Hematopoyéticas/metabolismo , Células Madre Hematopoyéticas/citología , Ratones , Proteína Fosfatasa 2C/metabolismo , Proteína Fosfatasa 2C/genética , beta Catenina/metabolismo , Hematopoyesis
20.
Opt Lett ; 49(19): 5627-5630, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39353023

RESUMEN

pH sensing is essential in various fields including healthcare, environmental monitoring, food safety, and agriculture. In this Letter, we propose a method for a wide-range pH measurement based on the direct response of liquid crystal (LC) to pH variations via the whispering gallery mode (WGM). The liquid crystal 4-cyano-4'-pentylbiphenyl (5CB) is selected for its excellent optoelectronic properties and the birefringence of 5CB microdroplets serving as spherical resonators. This sensor achieves wide-range pH sensing without any intermediaries. Polarized optical microscopy (POM) and WGM provide a qualitative morphological analysis and accurate quantitative spectral measurements. Under alkaline conditions (pH 7.6 to 13.3), POM images of 5CB microdroplets show a complete transition from bipolar to radial structures, with an average sensitivity of 1.78 nm/pH of redshift in WGM spectra. In acidic conditions (pH 6.65 to 1.5), structural changes observed by POM are minor, with a sensitivity of 1.06 nm/pH of blueshift in WGM spectra. This difference is attributed to the varying refractive indices of HCl and NaOH solutions. This method offers a reference for theoretical studies on pH and LC interactions and holds promise for the development of LC-based pH sensors.

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