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1.
Nat Immunol ; 25(9): 1742-1753, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39164477

RESUMEN

The differentiation and specificity of human CD4+ T follicular helper cells (TFH cells) after influenza vaccination have been poorly defined. Here we profiled blood and draining lymph node (LN) samples from human volunteers for over 2 years after two influenza vaccines were administered 1 year apart to define the evolution of the CD4+ TFH cell response. The first vaccination induced an increase in the frequency of circulating TFH (cTFH) and LN TFH cells at week 1 postvaccination. This increase was transient for cTFH cells, whereas the LN TFH cells further expanded during week 2 and remained elevated in frequency for at least 3 months. We observed several distinct subsets of TFH cells in the LN, including pre-TFH cells, memory TFH cells, germinal center (GC) TFH cells and interleukin-10+ TFH cell subsets beginning at baseline and at all time points postvaccination. The shift toward a GC TFH cell phenotype occurred with faster kinetics after the second vaccine compared to the first vaccine. We identified several influenza-specific TFH cell clonal lineages, including multiple responses targeting internal influenza virus proteins, and found that each TFH cell state was attainable within a clonal lineage. Thus, human TFH cells form a durable and dynamic multitissue network.


Asunto(s)
Diferenciación Celular , Centro Germinal , Vacunas contra la Influenza , Gripe Humana , Células T Auxiliares Foliculares , Vacunación , Humanos , Vacunas contra la Influenza/inmunología , Células T Auxiliares Foliculares/inmunología , Gripe Humana/inmunología , Gripe Humana/prevención & control , Centro Germinal/inmunología , Diferenciación Celular/inmunología , Ganglios Linfáticos/inmunología , Adulto , Femenino , Masculino , Persona de Mediana Edad , Interleucina-10/inmunología , Interleucina-10/metabolismo , Memoria Inmunológica/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Adulto Joven
2.
Nat Immunol ; 22(3): 336-346, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33574616

RESUMEN

The anatomic location and immunologic characteristics of brain tumors result in strong lymphocyte suppression. Consequently, conventional immunotherapies targeting CD8 T cells are ineffective against brain tumors. Tumor cells escape immunosurveillance by various mechanisms and tumor cell metabolism can affect the metabolic states and functions of tumor-infiltrating lymphocytes. Here, we discovered that brain tumor cells had a particularly high demand for oxygen, which affected γδ T cell-mediated antitumor immune responses but not those of conventional T cells. Specifically, tumor hypoxia activated the γδ T cell protein kinase A pathway at a transcriptional level, resulting in repression of the activatory receptor NKG2D. Alleviating tumor hypoxia reinvigorated NKG2D expression and the antitumor function of γδ T cells. These results reveal a hypoxia-mediated mechanism through which brain tumors and γδ T cells interact and emphasize the importance of γδ T cells for antitumor immunity against brain tumors.


Asunto(s)
Neoplasias Encefálicas/inmunología , Citotoxicidad Inmunológica , Glioblastoma/inmunología , Linfocitos Intraepiteliales/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Escape del Tumor , Microambiente Tumoral , Animales , Apoptosis , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Antígenos CD8/genética , Antígenos CD8/metabolismo , Línea Celular Tumoral , Técnicas de Cocultivo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Regulación Neoplásica de la Expresión Génica , Genes Codificadores de la Cadena delta de los Receptores de Linfocito T , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patología , Humanos , Linfocitos Intraepiteliales/metabolismo , Linfocitos Intraepiteliales/patología , Linfocitos Infiltrantes de Tumor/metabolismo , Linfocitos Infiltrantes de Tumor/patología , Masculino , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones Noqueados , Ratones Desnudos , Subfamilia K de Receptores Similares a Lectina de Células NK/genética , Subfamilia K de Receptores Similares a Lectina de Células NK/metabolismo , Fenotipo , Transducción de Señal , Hipoxia Tumoral
3.
Nature ; 623(7989): 942-948, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37968401

RESUMEN

Magic-angle twisted trilayer graphene (MATTG) exhibits a range of strongly correlated electronic phases that spontaneously break its underlying symmetries1,2. Here we investigate the correlated phases of MATTG using scanning tunnelling microscopy and identify marked signatures of interaction-driven spatial symmetry breaking. In low-strain samples, over a filling range of about two to three electrons or holes per moiré unit cell, we observe atomic-scale reconstruction of the graphene lattice that accompanies a correlated gap in the tunnelling spectrum. This short-scale restructuring appears as a Kekulé supercell-implying spontaneous inter-valley coherence between electrons-and persists in a wide range of magnetic fields and temperatures that coincide with the development of the gap. Large-scale maps covering several moiré unit cells further reveal a slow evolution of the Kekulé pattern, indicating that atomic-scale reconstruction coexists with translation symmetry breaking at a much longer moiré scale. We use auto-correlation and Fourier analyses to extract the intrinsic periodicity of these phases and find that they are consistent with the theoretically proposed incommensurate Kekulé spiral order3,4. Moreover, we find that the wavelength characterizing moiré-scale modulations monotonically decreases with hole doping away from half-filling of the bands and depends weakly on the magnetic field. Our results provide essential insights into the nature of the correlated phases of MATTG in the presence of strain and indicate that superconductivity can emerge from an inter-valley coherent parent state.

4.
Nature ; 606(7914): 494-500, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35705819

RESUMEN

Magic-angle twisted trilayer graphene (MATTG) has emerged as a moiré material that exhibits strong electronic correlations and unconventional superconductivity1,2. However, local spectroscopic studies of this system are still lacking. Here we perform high-resolution scanning tunnelling microscopy and spectroscopy of MATTG that reveal extensive regions of atomic reconstruction favouring mirror-symmetric stacking. In these regions, we observe symmetry-breaking electronic transitions and doping-dependent band-structure deformations similar to those in magic-angle bilayers, as expected theoretically given the commonality of flat bands3,4. Most notably in a density window spanning two to three holes per moiré unit cell, the spectroscopic signatures of superconductivity are manifest as pronounced dips in the tunnelling conductance at the Fermi level accompanied by coherence peaks that become gradually suppressed at elevated temperatures and magnetic fields. The observed evolution of the conductance with doping is consistent with a gate-tunable transition from a gapped superconductor to a nodal superconductor, which is theoretically compatible with a sharp transition from a Bardeen-Cooper-Schrieffer superconductor to a Bose-Einstein-condensation superconductor with a nodal order parameter. Within this doping window, we also detect peak-dip-hump structures that suggest that superconductivity is driven by strong coupling to bosonic modes of MATTG. Our results will enable further understanding of superconductivity and correlated states in graphene-based moiré structures beyond twisted bilayers5.

5.
Nature ; 589(7843): 536-541, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33462504

RESUMEN

Magic-angle twisted bilayer graphene (MATBG) exhibits a range of correlated phenomena that originate from strong electron-electron interactions. These interactions make the Fermi surface highly susceptible to reconstruction when ±1, ±2 and ±3 electrons occupy each moiré unit cell, and lead to the formation of various correlated phases1-4. Although some phases have been shown to have a non-zero Chern number5,6, the local microscopic properties and topological character of many other phases have not yet been determined. Here we introduce a set of techniques that use scanning tunnelling microscopy to map the topological phases that emerge in MATBG in a finite magnetic field. By following the evolution of the local density of states at the Fermi level with electrostatic doping and magnetic field, we create a local Landau fan diagram that enables us to assign Chern numbers directly to all observed phases. We uncover the existence of six topological phases that arise from integer fillings in finite fields and that originate from a cascade of symmetry-breaking transitions driven by correlations7,8. These topological phases can form only for a small range of twist angles around the magic angle, which further differentiates them from the Landau levels observed near charge neutrality. Moreover, we observe that even the charge-neutrality Landau spectrum taken at low fields is considerably modified by interactions, exhibits prominent electron-hole asymmetry, and features an unexpectedly large splitting between zero Landau levels (about 3 to 5 millielectronvolts). Our results show how strong electronic interactions affect the MATBG band structure and lead to correlation-enabled topological phases.

6.
Nature ; 583(7816): 379-384, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32669697

RESUMEN

Magic-angle twisted bilayer graphene (TBG), with rotational misalignment close to 1.1 degrees, features isolated flat electronic bands that host a rich phase diagram of correlated insulating, superconducting, ferromagnetic and topological phases1-6. Correlated insulators and superconductivity have been previously observed only for angles within 0.1 degree of the magic angle and occur in adjacent or overlapping electron-density ranges; nevertheless, the origins of these states and the relation between them remain unclear, owing to their sensitivity to microscopic details. Beyond twist angle and strain, the dependence of the TBG phase diagram on the alignment4,6 and thickness of the insulating hexagonal boron nitride (hBN)7,8 used to encapsulate the graphene sheets indicates the importance of the microscopic dielectric environment. Here we show that adding an insulating tungsten diselenide (WSe2) monolayer between the hBN and the TBG stabilizes superconductivity at twist angles much smaller than the magic angle. For the smallest twist angle of 0.79 degrees, superconductivity is still observed despite the TBG exhibiting metallic behaviour across the whole range of electron densities. Finite-magnetic-field measurements further reveal weak antilocalization signatures as well as breaking of fourfold spin-valley symmetry, consistent with spin-orbit coupling induced in the TBG via its proximity to WSe2. Our results constrain theoretical explanations for the emergence of superconductivity in TBG and open up avenues towards engineering quantum phases in moiré systems.

7.
Ann Neurol ; 95(3): 596-606, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38054838

RESUMEN

OBJECTIVE: Spinal and bulbar muscular atrophy (SBMA) is characterized by slow, progressive bulbar and limb muscle weakness; however, the pattern of progression of muscle fat infiltration remains unclear. We assessed the progression of muscle involvement in 81 patients with SBMA using whole-body muscle magnetic resonance imaging (MRI), alongside clinical and laboratory findings. METHODS: This prospective study included patients with genetically confirmed SBMA who underwent whole-body muscle MRI. We analyzed muscle fat infiltration and the pattern of involved muscles using cluster analysis, visualizing the sequential progression of fat infiltration. Muscle clusters demonstrated correlation with clinical scales and laboratory findings. Additionally, linear regression analysis was performed to identify the MRI section most strongly associated with 6-minute walk test (6MWT). RESULTS: We included 81 patients with SBMA (age = 54.3 years). After categorizing the patients into 6 clusters based on the pattern of muscle fat infiltration, we observed that muscle involvement began in the posterior calf and progressed to the posterior thigh, pelvis, trunk, anterior thigh, medial thigh, anterior calf, and upper extremity muscles. These muscle clusters correlated significantly with disease duration (τ = 0.47, p < 0.001), 6MWT (τ = -0.49, p < 0.001), and serum creatinine level (τ = -0.46, p < 0.001). The whole-body MRI indicated the thigh as the section most significantly correlated with 6MWT. INTERPRETATION: We used whole-body muscle MRI to determine the sequential progression of the fat infiltration in SBMA. Our findings may enable the identification of objective and reliable imaging outcome measures in the study of the natural history or future clinical trials of SBMA. ANN NEUROL 2024;95:596-606.


Asunto(s)
Atrofia Bulboespinal Ligada al X , Atrofia Muscular Espinal , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Atrofia Bulboespinal Ligada al X/diagnóstico por imagen , Atrofia Bulboespinal Ligada al X/patología , Atrofia Muscular/patología , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/patología , Atrofia Muscular Espinal/diagnóstico por imagen , Atrofia Muscular Espinal/patología , Imagen por Resonancia Magnética
8.
Ann Neurol ; 95(6): 1040-1054, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38520151

RESUMEN

OBJECTIVES: Intracerebral hemorrhage (ICH) and cerebral microbleeds (CMB) in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy are more common in East Asian populations than in people of white European ancestry. We hypothesized that the ethnic difference is explained by the East Asian-specific NOTCH3 p.R75P mutation. METHODS: This retrospective observational study included 118 patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy in Japanese and Korean cohorts. We investigated whether the p.R75P mutation is associated with symptomatic ICH and multiple CMB (>5) using quasi-Poisson regression models. We predicted the NOTCH3 extracellular domain protein structures in silico and graded NOTCH3 extracellular domain immunostaining in skin vessels of some patients, with subsequent comparisons between p.R75P and other conventional mutations. RESULTS: Among 63 Japanese patients (median age 55 years; 56% men), 15 had a p.R75P mutation, significantly associated with symptomatic ICH (adjusted relative risk 9.56, 95% CI 2.45-37.31), multiple CMB (3.00, 1.34-6.71), and absence of temporopolar lesions (4.91, 2.29-10.52) after adjustment for age, sex, hypertension, and antithrombotics. In the Korean cohort (n = 55; median age 55 years; 51% men), the p.R75P mutation (n = 13) was also associated with symptomatic ICH (8.11, 1.83-35.89), multiple CMB (1.90, 1.01-3.56), and absence of temporopolar lesions (2.32, 1.08-4.97). Structural analysis revealed solvent-exposed free cysteine thiols in conventional mutations, directly causing aggregation, whereas a stereochemically incompatible proline residue structure in p.R75P lowers correct disulfide bond formation probability, indirectly causing aggregation. Pathologically, the p.R75P mutation resulted in less vascular NOTCH3 extracellular domain accumulation than the other conventional mutations. INTERPRETATION: NOTCH3 p.R75P mutation is associated with hemorrhagic presentations, milder temporopolar lesions, and distinct mutant protein structure properties. ANN NEUROL 2024;95:1040-1054.


Asunto(s)
CADASIL , Hemorragia Cerebral , Mutación , Receptor Notch3 , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pueblo Asiatico/genética , CADASIL/genética , Hemorragia Cerebral/genética , Pueblos del Este de Asia/genética , Japón , Mutación/genética , Receptor Notch3/genética , República de Corea , Estudios Retrospectivos
9.
Stem Cells ; 42(3): 251-265, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38051601

RESUMEN

Human periodontal ligament cells (hPDLCs) cultured from periodontal ligament (PDL) tissue contain postnatal stem cells that can be differentiated into PDL fibroblasts. We obtained PDL fibroblasts from hPDLCs by treatment with low concentrations of TGF-ß1. Since the extracellular matrix and cell surface molecules play an important role in differentiation, we had previously developed a series of monoclonal antibodies against PDL fibroblast-specific cell surface molecules. One of these, the anti-PDL51 antibody, recognized a protein that was significantly upregulated in TGF-ß1-induced PDL fibroblasts and highly accumulated in the PDL region of the tooth root. Mass spectrometry revealed that the antigen recognized by the anti-PDL51 antibody was leucine-rich repeat containing 15 (LRRC15), and this antibody specifically recognized the extracellular glycosylated moiety of LRRC15. Experiments presented here show that as fibroblastic differentiation progresses, increased amounts of LRRC15 localized at the cell surface and membrane. Inhibition of LRRC15 by siRNA-mediated depletion and by antibody blocking resulted in downregulation of the representative PDL fibroblastic markers. Moreover, following LRRC15 inhibition, the directed and elongated cell phenotypes disappeared, and the long processes of the end of the cell body were no longer found. Through a specific interaction between integrin ß1 and LRRC15, the focal adhesion kinase signaling pathway was activated in PDL fibroblasts. Furthermore, it was shown that increased LRRC15 was important for the activation of the integrin-mediated cell adhesion signal pathway for regulation of cellular functions, including fibroblastic differentiation, proliferation, and cell migration arising from the expression of PDL-related genes in TGF-ß1-induced PDL fibroblastic differentiation.


Asunto(s)
Ligamento Periodontal , Factor de Crecimiento Transformador beta1 , Humanos , Factor de Crecimiento Transformador beta1/metabolismo , Adhesión Celular , Leucina/metabolismo , Proliferación Celular , Diferenciación Celular , Transducción de Señal , Fibroblastos/metabolismo , Integrinas/metabolismo , Células Cultivadas , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo
10.
Am J Gastroenterol ; 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39292188

RESUMEN

INTRODUCTION: Noninvasive stool DNA-based methylation testing has emerged as an effective strategy for the early colorectal cancer (CRC) detection. Syndecan-2 (SDC2) methylation frequently occurs in all stages of CRC; therefore, the aim of this study was to evaluate the clinical performance of a stool DNA-based SDC2 methylation test for detecting CRC in asymptomatic or high-risk CRC populations. METHODS: This multicenter prospective study was conducted to determine the clinical performance of the SDC2 methylation test on stool DNA using real-time polymerase chain reaction. Stool samples were collected from asymptomatic individuals before colonoscopy, and the test results were independently analyzed through comparison with colonoscopic findings and pathological outcomes as reference standards. RESULTS: Of the 1,124 evaluable participants, 20 had CRC, 73 had advanced adenomatous polyps (≥1.0 cm), 469 had nonadvanced adenomatous polyps (<1.0 cm), 178 had non-neoplastic polyps, and 384 had negative colonoscopy results. The stool SDC2 methylation test had a sensitivity and specificity of 95.0% and 81.5%, respectively, for detecting CRC, while the sensitivity for detecting advanced adenomatous polyps and CRC was 58.1%. The rate of adenoma detection increased with polyp size (P < 0.01), and sensitivity was not associated with CRC stage (P = 0.864). DISCUSSION: The stool DNA-based SDC2 methylation test attained a high sensitivity for CRC detection in an asymptomatic high-risk population. Further large-scale clinical studies are required to validate the clinical utility of this test as a population-based CRC screening tool.

11.
Small ; : e2405493, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39087376

RESUMEN

Simultaneous monitoring of critical parameters (e.g., pressure, shear, and temperature) at bony prominences is essential for the prevention of pressure injuries in a systematic manner. However, the development of wireless sensor array for accurate mapping of risk factors has been limited due to the challenges in the convergence of wireless technologies and wearable sensor arrays with a thin and small form factor. Herein, a battery-free, wireless, miniaturized multi-modal sensor array is introduced for continuous mapping of pressure, shear, and temperature at skin interfaces. The sensor array includes an integrated pressure and shear sensor consisting of 3D strain gauges and micromachined components. The mechanically decoupled design of the integrated sensor enables reliable data acquisition of pressure and shear at skin interfaces without the need for additional data processing. The sensor platform enables the analysis of interplay among localized pressure, shear, and temperature in response to changes in the patient's movement, posture, and bed inclination. The validation trials using a novel combination of wireless sensor arrays and customized pneumatic actuator demonstrate the efficacy of the platform in continuous monitoring and efficient redistribution of pressure and shear without repositioning, thereby improving the patient's quality of life.

12.
Artículo en Inglés | MEDLINE | ID: mdl-38777578

RESUMEN

BACKGROUND: The risk-benefit relationship of immunosuppressive therapies (ISTs) for elderly patients with neuromyelitis optica spectrum disorder (NMOSD) is not well established. This study aimed to investigate the safety and efficacy of IST in elderly patients with NMOSD. METHODS: This retrospective study analysed IST efficacy and safety in 101 patients with aquaporin-4 antibody-positive NMOSD aged over 65 years, treated for at least 6 months at five Korean referral centres, focusing on relapse rates, infection events and discontinuation due to adverse outcomes. RESULTS: The mean age at disease onset was 59.8 years, and female-to-male ratio was 4:1. Concomitant comorbidities at NMOSD diagnosis were found in 87 patients (86%). The median Expanded Disability Status Scale score at the initiation of IST was 3.5. The administered ISTs included azathioprine (n=61, 60%), mycophenolate mofetil (MMF) (n=48, 48%) and rituximab (n=41, 41%). Over a median of 5.8 years of IST, 58% of patients were relapse-free. The median annualised relapse rate decreased from 0.76 to 0 (p<0.001), and 81% experienced improved or stabilised disability. Patients treated with rituximab had a higher relapse-free rate than those treated with azathioprine or MMF (p=0.022). During IST, 21 patients experienced 25 severe infection events (SIEs) over the age of 65 years, and 3 died from pneumonia. 14 patients (14%) experienced 17 adverse events that led to switching or discontinuation of IST. When comparing the incidence rates of SIEs and adverse events, no differences were observed among patients receiving azathioprine, MMF and rituximab. CONCLUSION: In elderly patients with NMOSD, IST offers potential benefits in reducing relapse rates alongside a tolerable risk of adverse events.

13.
Langmuir ; 40(9): 4567-4578, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38377328

RESUMEN

Capacitive deionization (CDI) has emerged as a promising desalination technology and recently promoted the development of multichannel membrane capacitive deionization (MC-MCDI). In MC-MCDI, the independent control of multiflow channels, including the feed and electrolyte channels, enables the optimization of electrode operation in various modes, such as concentration gradients and reverse voltage discharge, facilitating semicontinuous operation. Moreover, the integration of redox couples into MC-MCDI has led to advancements in redox-mediated desalination. Specifically, the introduction of redox-active species helps enhance the ion removal efficiency and reduce energy consumption during desalination. This systematic approach, combining principles from CDI and electrodialysis, results in more sustainable and efficient desalination. These advancements have contributed to improved desalination performance and practical feasibility, rendering MC-MCDI an increasingly attractive option for addressing water scarcity challenges. Despite the considerable interest in and potential of this process, there is currently no comprehensive review available that covers the operational features and applications of MC-MCDI. Therefore, this Review provides an overview of recent research progress, focusing on the unique cell configuration, vital operation principles, and potential advantages over conventional CDI. Additionally, innovative applications of MC-MCDI are discussed. The Review concludes with insights into future research directions, potential opportunities in industrial desalination technology, and the fundamental and practical challenges for successful implementation.

14.
Inorg Chem ; 63(2): 1414-1426, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38166391

RESUMEN

Reevaluating the composition of the double metal cyanide catalyst (DMC) as a salt of (NC)6Co3- anions with 1:1 Zn2+/(X)Zn+ cations (X = Cl, RO, AcO), we prepared a series of well-defined DMCs, [ClZn+][Zn2+][(NC)6Co3-][ROH], [(RO)Zn+][Zn2+][(NC)6Co3-], [(AcO)Zn+][Zn2+][(NC)6Co3-], [(RO)Zn+]p[ClZn+](1-p)[Zn2+][(NC)6Co3-], [(AcO)Zn+]p[(tBuO)Zn+]q[Zn2+][(NC)6Co3-], and [(AcO)Zn+]p[(tBuO)Zn+]q[ClZn+]r[Zn2+][(NC)6Co3-]. The structure of [(MeOC3H6O)Zn+][Zn2+][(NC)6Co3-] was precisely determined at the atomic level through Rietveld refinement of the synchrotron X-ray powder diffraction data. By evaluating the catalyst's performance in both propylene oxide (PO) polymerization and PO/CO2 copolymerization, a correlation between structure and performance was established on various aspects including activity, dispersity, unsaturation level, and carbonate fraction in the resulting polyols. Ultimately, our study identified highly efficient catalysts that outperformed the state-of-the-art benchmark DMC not only in PO polymerization [DMC-(OAc/OtBu/Cl)(0.59/0.38/0.15)] but also in PO/CO2 copolymerization [DMC-(OAc/OtBu)(0.95/0.08)].

15.
J Pathol ; 260(4): 443-454, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37341658

RESUMEN

PIK3CA mutations in cancer regulate tumour immunogenicity. Given that PIK3CA mutation subtypes influence therapeutic responses to AKT inhibitor and that H1047R mutation confers selective growth advantages after immunotherapy, we hypothesised that immune phenotypes may depend on PIK3CA mutation subtypes. We investigated 133 gastric cancers (GCs) harbouring PIK3CA mutation [21 E542K (15.8%), 36 E545X (27.1%), 26 H1047X (19.5%), and 46 others (34.6%)]. Four patients (3.0%) had a combination of mutations (E542K + E545K in 3 patients and E545K + H1047R in 1 patient). Epstein-Barr virus (EBV) and microsatellite instability (MSI) status, PD-L1 (programmed death-ligand 1) combined positive score (CPS), and stromal tumour-infiltrating lymphocytes (TILs) were assessed. Concurrent genomic alterations, GeoMx digital spatial profiling (DSP), and OPAL multiplex immunohistochemistry (mIHC) were analysed, and correlation between the two assays was investigated. Of the 133 PIK3CA-mutant (PIK3CAm ) GCs, MSI-high GC was significantly frequent in the H1047X mutation subtype (p = 0.005), while EBV positivity did not affect the mutation subtypes. There was no significant survival difference between the E542K, E545X, and H1047X subgroups. However, in the subgroup analysis for EBV-positive GC, H1047Xm GC showed a trend towards shorter survival than E542K and E545Xm GC (p = 0.090 and 0.062). With DSP analysis, H1047Xm GC showed elevated VISTA (p = 0.0003), granzyme B (p < 0.0001), CD4 (p = 0.0001), and CD45 (p < 0.0001) expression compared with the E542Km or E545Xm GC subgroups, and only VISTA expression remained significant (p < 0.0001) using OPAL mIHC. DSP and OPAL analyses showed a moderate correlation of CD4 (ρ = 0.42, p = 0.004) and CD8 (ρ = 0.62, p < 0.001) expression levels in a comparison of six antibodies. Immune-related protein expression levels were evident when classified by the three PIK3CA hotspot mutations, and H1047Xm GC showed the highest immune-related protein expression compared with E542Km or E545Xm GC. Our results demonstrated distinct immune profiles in GC with PIK3CA hotspot mutations using GeoMx DSP and OPAL mIHC, and there was a correlation between the two multiplex platforms. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Asunto(s)
Carcinoma , Infecciones por Virus de Epstein-Barr , Neoplasias Gástricas , Humanos , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Neoplasias Gástricas/patología , Inestabilidad de Microsatélites , Antígeno B7-H1 , Fosfatidilinositol 3-Quinasa Clase I/genética , Mutación
16.
Brain ; 146(7): 2957-2974, 2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-37062541

RESUMEN

Reactive astrogliosis is a hallmark of Alzheimer's disease (AD). However, a clinically validated neuroimaging probe to visualize the reactive astrogliosis is yet to be discovered. Here, we show that PET imaging with 11C-acetate and 18F-fluorodeoxyglucose (18F-FDG) functionally visualizes the reactive astrocyte-mediated neuronal hypometabolism in the brains with neuroinflammation and AD. To investigate the alterations of acetate and glucose metabolism in the diseased brains and their impact on the AD pathology, we adopted multifaceted approaches including microPET imaging, autoradiography, immunohistochemistry, metabolomics, and electrophysiology. Two AD rodent models, APP/PS1 and 5xFAD transgenic mice, one adenovirus-induced rat model of reactive astrogliosis, and post-mortem human brain tissues were used in this study. We further curated a proof-of-concept human study that included 11C-acetate and 18F-FDG PET imaging analyses along with neuropsychological assessments from 11 AD patients and 10 healthy control subjects. We demonstrate that reactive astrocytes excessively absorb acetate through elevated monocarboxylate transporter-1 (MCT1) in rodent models of both reactive astrogliosis and AD. The elevated acetate uptake is associated with reactive astrogliosis and boosts the aberrant astrocytic GABA synthesis when amyloid-ß is present. The excessive astrocytic GABA subsequently suppresses neuronal activity, which could lead to glucose uptake through decreased glucose transporter-3 in the diseased brains. We further demonstrate that 11C-acetate uptake was significantly increased in the entorhinal cortex, hippocampus and temporo-parietal neocortex of the AD patients compared to the healthy controls, while 18F-FDG uptake was significantly reduced in the same regions. Additionally, we discover a strong correlation between the patients' cognitive function and the PET signals of both 11C-acetate and 18F-FDG. We demonstrate the potential value of PET imaging with 11C-acetate and 18F-FDG by visualizing reactive astrogliosis and the associated neuronal glucose hypometablosim for AD patients. Our findings further suggest that the acetate-boosted reactive astrocyte-neuron interaction could contribute to the cognitive decline in AD.


Asunto(s)
Enfermedad de Alzheimer , Ratones , Humanos , Ratas , Animales , Enfermedad de Alzheimer/metabolismo , Fluorodesoxiglucosa F18/metabolismo , Astrocitos/metabolismo , Radioisótopos de Carbono/metabolismo , Gliosis/diagnóstico por imagen , Encéfalo/patología , Tomografía de Emisión de Positrones/métodos , Ácido gamma-Aminobutírico/metabolismo
17.
Environ Res ; 245: 118076, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38160977

RESUMEN

Owing to the ever-increasing generation of plastic waste, the need to develop environmentally friendly disposal methods has increased. This study explored the potential of waste plastic straw to generate valuable light olefins and monocyclic aromatic hydrocarbons (MAHs) via catalytic pyrolysis using high-silica zeolite-based catalysts. HZSM-5 (SiO2/Al2O3:200) exhibited superior performance, yielding more light olefins (49.8 wt%) and a higher MAH content than Hbeta (300). This was attributed to the increased acidity and proper shape selectivity. HZSM-5 displayed better coking resistance (0.7 wt%) than Hbeta (4.4 wt%) by impeding secondary reactions, limiting coke precursor formation. The use of HZSM-5 (80) resulted in higher MAHs and lower light olefins than HZSM-5 (200) because of its higher acidity. Incorporation of Co into HZSM-5 (200) marginally lowered light olefin yield (to 44.0 wt%) while notably enhancing MAH production and boosting propene selectivity within the olefin composition. These observations are attributed to the well-balanced coexistence of Lewis and Brønsted acid sites, which stimulated the carbonium ion mechanism and induced H-transfer, cyclization, Diels-alder, and dehydrogenation reactions. The catalytic pyrolysis of plastic straw over high-silica and metal-loaded HZSM-5 catalysts has been suggested as an efficient and sustainable method for transforming plastic waste materials into valuable light olefins and MAHs.


Asunto(s)
Hidrocarburos Aromáticos , Zeolitas , Dióxido de Silicio , Pirólisis , Calor , Biomasa , Alquenos , Catálisis , Hidrocarburos
18.
BMC Vet Res ; 20(1): 233, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38807154

RESUMEN

Canine mammary gland tumors (MGT) have a poor prognosis in intact female canines, posing a clinical challenge. This study aimed to establish novel canine mammary cancer cell lines from primary tumors and characterize their cellular and molecular features to find potential therapeutic drugs. The MGT cell lines demonstrated rapid cell proliferation and colony formation in an anchorage-independent manner. Vimentin and α-SMA levels were significantly elevated in MGT cell lines compared to normal canine kidney (MDCK) cells, while CDH1 expression was either significantly lower or not detected at all, based on quantitative real-time PCR (qRT-PCR) analysis. Functional annotation and enrichment analysis revealed that epithelial-mesenchymal transition (EMT) phenotypes and tumor-associated pathways, particularly the PI3K/Akt signaling pathway, were upregulated in MGT cells. BYL719 (Alpelisib), a PI3K inhibitor, was also examined for cytotoxicity on the MGT cell lines. The results show that BYL719 can significantly inhibit the proliferation of MGT cell lines in vitro. Overall, our findings suggest that the MGT cell lines may be valuable for future studies on the development, progression, metastasis, and management of tumors.


Asunto(s)
Enfermedades de los Perros , Neoplasias Mamarias Animales , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Animales , Perros , Femenino , Línea Celular Tumoral , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Enfermedades de los Perros/tratamiento farmacológico , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Proliferación Celular/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Transducción de Señal , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacología
19.
Mol Cell ; 62(1): 7-20, 2016 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-27052731

RESUMEN

The Src-homology 2 (SH2) domain is a protein interaction domain that directs myriad phosphotyrosine (pY)-signaling pathways. Genome-wide screening of human SH2 domains reveals that ∼90% of SH2 domains bind plasma membrane lipids and many have high phosphoinositide specificity. They bind lipids using surface cationic patches separate from pY-binding pockets, thus binding lipids and the pY motif independently. The patches form grooves for specific lipid headgroup recognition or flat surfaces for non-specific membrane binding and both types of interaction are important for cellular function and regulation of SH2 domain-containing proteins. Cellular studies with ZAP70 showed that multiple lipids bind its C-terminal SH2 domain in a spatiotemporally specific manner and thereby exert exquisite spatiotemporal control over its protein binding and signaling activities in T cells. Collectively, this study reveals how lipids control SH2 domain-mediated cellular protein-protein interaction networks and suggest a new strategy for therapeutic modulation of pY-signaling pathways.


Asunto(s)
Metabolismo de los Lípidos , Linfocitos T/metabolismo , Proteína Tirosina Quinasa ZAP-70/química , Proteína Tirosina Quinasa ZAP-70/metabolismo , Dominios Homologos src , Sitios de Unión , Células Cultivadas , Humanos , Células Jurkat , Modelos Moleculares , Simulación del Acoplamiento Molecular , Fosfotirosina/efectos de los fármacos , Fosfotirosina/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , Transducción de Señal
20.
BMC Pregnancy Childbirth ; 24(1): 93, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38297236

RESUMEN

BACKGROUND: To evaluate the clinical significance of noninvasive prenatal testing (NIPT) for detecting fetal sex chromosome aneuploidies (SCAs) in Korean pregnant women. METHODS: We retrospectively analyzed NIPT data from 9,176 women with singleton pregnancies referred to the CHA Biotech genome diagnostics center. Cell-free fetal DNA (cffDNA) was extracted from maternal peripheral blood, and high-throughput massively parallel sequencing was conducted. Subsequently, the positive NIPT results for SCA were validated via karyotype and chromosomal microarray analyses. RESULTS: Overall, 46 cases were SCA positive after NIPT, including 20, 12, 8, and 6 for Turner, triple X, Klinefelter, and Jacob syndromes, respectively. Among 37 women with invasive prenatal diagnosis, 19 had true positive NIPT results. The overall positive predictive value (PPV) of NIPT for detecting SCAs was 51.35%. The PPV was 18.75% for Turner, 88.89% for triple X, 71.43% for Klinefelter, and 60.00% for Jacob's syndromes. NIPT accuracy for detecting sex chromosome trisomies was higher than that for sex chromosome monosomy (P = 0.002). No significant correlation was observed between fetal SCA incidence and maternal age (P = 0.914), except for the borderline significance of Jacob's syndrome (P = 0.048). No significant differences were observed when comparing NIPT and karyotyping validation for fetal SCA according to pregnancy characteristics. CONCLUSION: Our data suggest that NIPT can reliably screen for SCAs, and it performed better in predicting sex chromosome trisomies compared with monosomy X. No correlation was observed between maternal age and fetal SCA incidence, and no association was observed between different pregnancy characteristics. The accuracy of these findings requires improvements; however, our study provides an important reference for clinical genetic counseling and further management. Larger scale studies, considering confounding factors, are required for accurate evaluation.


Asunto(s)
Pruebas Prenatales no Invasivas , Trastornos de los Cromosomas Sexuales , Trisomía , Cariotipo XYY , Femenino , Embarazo , Humanos , Estudios Retrospectivos , Mujeres Embarazadas , Aneuploidia , Aberraciones Cromosómicas Sexuales , Diagnóstico Prenatal/métodos , Cromosomas Sexuales/genética , República de Corea
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