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1.
Nat Immunol ; 19(9): 973-985, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30127434

RESUMEN

Human inborn errors of IFN-γ immunity underlie mycobacterial diseases. We describe patients with Mycobacterium bovis (BCG) disease who are homozygous for loss-of-function mutations of SPPL2A. This gene encodes a transmembrane protease that degrades the N-terminal fragment (NTF) of CD74 (HLA invariant chain) in antigen-presenting cells. The CD74 NTF therefore accumulates in the HLA class II+ myeloid and lymphoid cells of SPPL2a-deficient patients. This toxic fragment selectively depletes IL-12- and IL-23-producing CD1c+ conventional dendritic cells (cDC2s) and their circulating progenitors. Moreover, SPPL2a-deficient memory TH1* cells selectively fail to produce IFN-γ when stimulated with mycobacterial antigens in vitro. Finally, Sppl2a-/- mice lack cDC2s, have CD4+ T cells that produce small amounts of IFN-γ after BCG infection, and are highly susceptible to infection with BCG or Mycobacterium tuberculosis. These findings suggest that inherited SPPL2a deficiency in humans underlies mycobacterial disease by decreasing the numbers of cDC2s and impairing IFN-γ production by mycobacterium-specific memory TH1* cells.


Asunto(s)
Ácido Aspártico Endopeptidasas/genética , Ácido Aspártico Endopeptidasas/metabolismo , Células Dendríticas/inmunología , Proteínas de la Membrana/metabolismo , Infecciones por Mycobacterium/inmunología , Mycobacterium bovis/fisiología , Mycobacterium tuberculosis/fisiología , Células TH1/inmunología , Tuberculosis/inmunología , Animales , Antígenos de Diferenciación de Linfocitos B/metabolismo , Células Cultivadas , Antígenos HLA/metabolismo , Antígenos de Histocompatibilidad Clase II/metabolismo , Humanos , Inmunidad , Memoria Inmunológica , Lactante , Interferón gamma/metabolismo , Linfadenopatía , Masculino , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mutación/genética , Infecciones por Mycobacterium/genética , Vacunación
2.
Nat Mater ; 23(3): 331-338, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37537355

RESUMEN

The properties of two-dimensional (2D) van der Waals materials can be tuned through nanostructuring or controlled layer stacking, where interlayer hybridization induces exotic electronic states and transport phenomena. Here we describe a viable approach and underlying mechanism for the assisted self-assembly of twisted layer graphene. The process, which can be implemented in standard chemical vapour deposition growth, is best described by analogy to origami and kirigami with paper. It involves the controlled induction of wrinkle formation in single-layer graphene with subsequent wrinkle folding, tearing and re-growth. Inherent to the process is the formation of intertwined graphene spirals and conversion of the chiral angle of 1D wrinkles into a 2D twist angle of a 3D superlattice. The approach can be extended to other foldable 2D materials and facilitates the production of miniaturized electronic components, including capacitors, resistors, inductors and superconductors.

3.
Phys Rev Lett ; 132(5): 056601, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38364175

RESUMEN

In this Letter, we theoretically explore the physical properties of a new type of three-dimensional graphite moiré superlattice, the bulk alternating twisted graphite (ATG) system with homogeneous twist angle, which is grown by in situ chemical vapor decomposition method. Compared to twisted bilayer graphene (TBG), the bulk ATG system is bestowed with an additional wave vector degree of freedom due to the extra dimensionality. As a result, when the twist angle of bulk ATG is smaller than twice of the magic angle of TBG, there always exist "magic momenta" which host topological flat bands with vanishing in-plane Fermi velocities. Most saliently, when the twist angle is relatively large, a dispersionless three-dimensional zeroth Landau level would emerge in the bulk ATG, which may give rise to robust three-dimensional quantum Hall effects and unusual quantum-Hall physics over a large range of twist angles.

4.
Eur Radiol ; 2024 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-38308680

RESUMEN

OBJECTIVES: To use three-dimensional real inversion recovery (3D-real IR) MRI to investigate correlations between endolymphatic hydrops (EH) grades or the degree of perilymphatic enhancement (PE) and clinical features of Ménière's disease (MD), as previous findings have been inconsistent. METHODS: A total of 273 consecutive patients with definite unilateral MD were retrospectively enrolled from September 2020 to October 2021. All patients underwent 3D-real IR and 3D-T2WI 6 h after intravenous gadolinium injection. MD-related symptom duration and vertigo frequency were recorded. EH grades were evaluated, the signal intensity ratio (SIR) was measured, and correlations between clinical features and EH, PE were assessed respectively. RESULTS: The study included 123 males and 150 females, with a mean age of 53.0 years. A longer duration of vertigo was associated with higher cochlear EH grades, whereas the opposite was true for the duration of aural fullness. A longer time since vertigo onset was associated with higher vestibular EH grades; the opposite was true for the duration of individual vertigo attacks. The multiple regression analysis revealed that age, tinnitus duration, and vestibular EH were risk factors for SIR. Furthermore, the low-frequency hearing threshold (HT) was a risk factor for cochlear and vestibular EH, and the SIR. CONCLUSION: The EH grade and SIR (an indicator for the quantitative evaluation of PE) were correlated with clinical features and HT of MD; thus, imaging can be a valuable tool in planning individualised treatment. CLINICAL RELEVANCE STATEMENT: This study revealed that the grade of endolymphatic hydrops and degree of perilymphatic enhancement positively correlates with the length of time since onset of clinical symptoms and hearing thresholds in patients with Ménière's disease, facilitating the tailored treatment. KEY POINTS: • Relationships between 3-dimensional real inversion recovery features and clinical symptoms in Ménière's disease are unknown. • Symptom duration and hearing thresholds correlated with endolymphatic hydrops grades and degree of perilymphatic enhancement. • MRI features correlate with MD severity; thus, imaging is valuable for planning tailored treatment.

5.
J Biochem Mol Toxicol ; 38(4): e23698, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38501767

RESUMEN

Accumulating evidence confirms that sleep insufficiency is a high risk factor for cognitive impairment, which involves inflammation and synaptic dysfunction. Resveratrol, an agonist of the Sirt1, has demonstrated anti-inflammation and neuroprotective effects in models of Alzheimer's disease, Parkinson's disease, and schizophrenia. However, the beneficial effects of resveratrol on sleep deprivation-induced cognitive deficits and its underlying molecular mechanisms are unclear. In the present study, thirty-two male C57BL/6 J mice were randomly divided into a Control+DMSO group, Control+Resveratrol group, SD+DMSO group, and SD+Resveratrol group. The mice in the SD+Resveratrol group underwent 5 days of sleep deprivation after pretreatment with resveratrol (50 mg/kg) for 2 weeks, while the mice in the SD+DMSO group only underwent sleep deprivation. After sleep deprivation, we evaluated spatial learning and memory function using the Morris water maze test. We used general molecular biology techniques to detect changes in levels of pro-inflammatory cytokines and Sirt1/miR-134 pathway-related synaptic plasticity proteins. We found that resveratrol significantly reversed sleep deprivation-induced learning and memory impairment, elevated interleukin-1ß, interleukin-6, and tumor necrosis factor-α levels, and decreased brain-derived neurotrophic factor, tyrosine kinase receptor B, postsynaptic density protein-95, and synaptophysin levels by activating the Sirt1/miR-134 pathway. In conclusion, resveratrol is a promising agent for preventing sleep deprivation-induced cognitive dysfunction by reducing pro-inflammatory cytokines and improving synaptic function via the Sirt1/miR-134 pathway.


Asunto(s)
Disfunción Cognitiva , MicroARNs , Masculino , Ratones , Animales , Resveratrol/farmacología , Privación de Sueño/complicaciones , Privación de Sueño/metabolismo , Sirtuina 1/metabolismo , Dimetilsulfóxido/metabolismo , Dimetilsulfóxido/farmacología , Ratones Endogámicos C57BL , Disfunción Cognitiva/tratamiento farmacológico , Disfunción Cognitiva/etiología , Disfunción Cognitiva/prevención & control , Hipocampo/metabolismo , MicroARNs/metabolismo , Citocinas/metabolismo , Cognición
6.
Mol Genet Genomics ; 298(6): 1493-1503, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37845373

RESUMEN

Previous studies have observed relationships between immune cells and systemic lupus erythematosus (SLE), but their causal links remain undetermined. Based on the public available genome-wide association studies (GWAS) summary statistics, we conducted two-sample Mendelian randomization (MR) to evaluate the associations between 731 immune phenotypes and SLE pairs. Pairwise pleiotropy analysis was performed to identify pleiotropic genes for significant immunophenotype-SLE pairs. A comprehensive gene function analysis was undertaken to explore the mechanisms of immune cells in SLE. By using the instrumental variables extracted from GWAS data, we observed that increased levels of five immune phenotypes were causally associated with SLE risk (FDR < 0.05), that were CD20 on IgD+ CD38- naïve, BAFF-R on IgD+ CD38dim, CD39+ secreting Treg AC, CD14- CD16+ monocyte AC, and HLA DR on CD14+ monocyte. Pairwise gene-based analyses identified a total of 38 pleiotropic genes for 5 significant pairs identified and gene set enrichment analysis revealed the involvement of the identified pleiotropic genes in complex pathways (i.e., systemic lupus erythematosus, an integral component of luminal side of endoplasmic reticulum membrane, C-type lectin receptor signaling pathway and regulation of hormone secretion). This study demonstrates that the immune response influences the progression of SLE in a complex pattern. These findings greatly improve our understanding of the interaction between immune response and SLE risk and also aid in the design of therapeutic strategies from an immunological perspective.


Asunto(s)
Lupus Eritematoso Sistémico , Análisis de la Aleatorización Mendeliana , Humanos , Estudio de Asociación del Genoma Completo , Fenotipo , Transducción de Señal/genética , Lupus Eritematoso Sistémico/genética , Polimorfismo de Nucleótido Simple
7.
Neuroradiology ; 65(9): 1371-1379, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37328652

RESUMEN

PURPOSE: To determine whether magnetic resonance imaging (MRI) can improve diagnostic accuracy for definite and probable Ménière's disease (MD) based on perilymphatic enhancement (PE) and endolymphatic hydrops (EH). METHODS: 363 patients with unilateral MD (probable MD, n = 75 and definite MD, n = 288) were recruited. A three-dimensional zoomed imaging technique with parallel transmission SPACE real inversion recovery was performed 6 h after intravenous gadolinium injection to investigate the presence of PE and to evaluate the grading and location of EH. PE and EH characteristics were analyzed and compared between the probable and definite MD groups. RESULTS: The cochlear and vestibular EH grading on the affected side was more severe in the definite MD group than that in the probable MD group (P < 0.001). The EH locations within the inner ear on the affected side also differed between the two groups (χ2 = 81.15, P < 0.001). The signal intensity ratio (SIR) on the affected side was significantly higher in the definite MD group than in the probable MD group (t = 2.18, P < 0.05). The assessment of the combination of PE and EH parameters within the inner ear revealed a higher area under the curve (AUC) in the definite MD group (0.82) compared with the AUCs of the parameters assessed alone. CONCLUSION: The assessment of a combination of PE and EH parameters improved the diagnostic accuracy for probable and definite MD, suggesting that MRI findings may be clinically useful in the diagnosis of MD.


Asunto(s)
Hidropesía Endolinfática , Enfermedad de Meniere , Vestíbulo del Laberinto , Humanos , Enfermedad de Meniere/diagnóstico por imagen , Hidropesía Endolinfática/diagnóstico por imagen , Vestíbulo del Laberinto/patología , Inyecciones Intravenosas , Imagen por Resonancia Magnética/métodos , Imagenología Tridimensional
8.
Nano Lett ; 22(12): 4661-4668, 2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35640103

RESUMEN

Confined nanospaces provide a new platform to promote catalytic reactions. However, the mechanism of catalytic enhancement in the nanospace still requires insightful exploration due to the lack of direct visualization. Here, we report operando investigations on the etching and growth of graphene in a two-dimensional (2D) confined space between graphene and a Cu substrate. We observed that the graphene layer between the Cu and top graphene layer was surprisingly very active in etching (more than 10 times faster than the etching of the top graphene layer). More strikingly, at a relatively low temperature (∼530 °C), the etched carbon radicals dissociated from the bottom layer, in turn feeding the growth of the top graphene layer with a very high efficiency. Our findings reveal the in situ dynamics of the anomalous confined catalytic processes in 2D confined spaces and thus pave the way for the design of high-efficiency catalysts.

9.
J Sci Food Agric ; 103(6): 2939-2948, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36460619

RESUMEN

BACKGROUND: Calcium is an essential dietary mineral nutrient for humans. Digestive instability limits the bioavailability of calcium ions. Peptide-calcium chelate has been proven to excite higher calcium absorption than amino acid-calcium chelate, organic and inorganic calcium. Soy yogurt, which is produced via liquid-state fermentation using lactic acid bacteria, has a high amount of bioavailable calcium. In this study, a novel peptide with high calcium binding affinity was purified and identified from soy yogurt. The binding mechanism of peptide and calcium was then analyzed by bioinformatics and spectral analysis. Furthermore, the effect of the novel peptide on gastrointestinal stability by the Caco-2 cell model and calcium bioavailability in vivo were investigated by the zebrafish model. RESULTS: The results showed that a novel peptide was purified and identified as DEDEQIPSHPPR (CBP). Calcium ions probably coordinate with Glu-2 and Glu-4 carboxyl groups via salt bridges and interact with Asp-1, Asp-3, and Arg-12 in CBP via charge pairing. The calcium binding activity of the CBP was 36.64 ± 0.04 mg g-1 . Fourier transform infrared (FTIR) spectra showed that calcium spontaneously bound to the amino group nitrogen and oxygen atoms of the carboxyl group. The binding mode is either bidentate or unidentate, depending on the circumstances. More importantly, the CBP peptide substantially increased the bone mass in a zebrafish osteoporosis model. CONCLUSION: The more glutamic acid and aspartic acid, the high was the calcium affinity with peptide. Soy yogurt-derived peptides can be used as carriers of calcium ions throughout the gastrointestinal tract, which may be clinically useful for osteoporosis therapy. © 2022 Society of Chemical Industry.


Asunto(s)
Calcio , Osteoporosis , Humanos , Animales , Calcio/metabolismo , Simulación del Acoplamiento Molecular , Pez Cebra/metabolismo , Células CACO-2 , Yogur , Péptidos/química , Calcio de la Dieta/metabolismo
10.
J Am Chem Soc ; 144(12): 5606-5613, 2022 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-35297632

RESUMEN

Despite three decades of intense research efforts, the most fundamental question "why do carbon nanotubes grow?" remains unanswered. In fact, carbon nanotubes (CNTs) should not grow since the encapsulation of a catalyst with graphitic carbon is energetically more favorable than CNT growth in every aspect. Here, we answer this question using a theoretical model based on extensive first-principles and molecular dynamics calculations. We reveal a historically overlooked yet fundamental aspect of the CNT-catalyst interface, viz., that the interfacial energy of the CNT-catalyst edge is contact angle-dependent. The contact angle increases via graphitic cap lift-off, drastically decreasing the interfacial formation energy by up to 6-9 eV/nm, overcoming van der Waals cap-catalyst adhesion, and driving CNT growth. Mapping this remarkable and simple interplay allows us to understand, for the first time, why CNTs grow.


Asunto(s)
Nanotubos de Carbono , Catálisis , Simulación de Dinámica Molecular
11.
Osteoporos Int ; 33(9): 1957-1967, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35583602

RESUMEN

The widely recommended fracture prediction tool FRAX was developed based on and for the general population. Although several adjusted FRAX methods were suggested for type 2 diabetes (T2DM), they still need to be evaluated in T2DM cohort. INTRODUCTION: This study was undertaken to develop a prediction model for Chinese diabetes fracture risk (CDFR) and compare its performance with those of FRAX. METHODS: In this retrospective cohort study, 1730 patients with T2DM were enrolled from 2009.08 to 2013.07. Major osteoporotic fractures (MOFs) during follow-up were collected from Electronic Health Records (EHRs) and telephone interviews. Multivariate Cox regression with backward stepwise selection was used to fit the model. The performances of the CDFR model, FRAX, and adjusted FRAX were compared in the aspects of discrimination and calibration. RESULTS: 6.3% of participants experienced MOF during a median follow-up of 10 years. The final model (CDFR) included 8 predictors: age, gender, previous fracture, insulin use, diabetic peripheral neuropathy (DPN), total cholesterol, triglycerides, and apolipoprotein A. This model had a C statistic of 0.803 (95%CI 0.761-0.844) and calibration χ2 of 4.63 (p = 0.86). The unadjusted FRAX underestimated the MOF risk (calibration χ2 134.5, p < 0.001; observed/predicted ratio 2.62, 95%CI 2.17-3.08), and there was still significant underestimation after diabetes adjustments. Comparing FRAX, the CDFR had a higher AUC, lower calibration χ2, and better reclassification of MOF. CONCLUSION: The CDFR model has good performance in 10-year MOF risk prediction in T2DM, especially in patients with insulin use or DPN. Future work is needed to validate our model in external cohort(s).


Asunto(s)
Diabetes Mellitus Tipo 2 , Fracturas de Cadera , Insulinas , Osteoporosis , Fracturas Osteoporóticas , Densidad Ósea , Diabetes Mellitus Tipo 2/complicaciones , Fracturas de Cadera/epidemiología , Humanos , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/etiología , Estudios Retrospectivos , Medición de Riesgo/métodos , Factores de Riesgo
12.
J Gastroenterol Hepatol ; 37(6): 973-982, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35384041

RESUMEN

BACKGROUND AND AIM: Humans with inborn errors of immunity (IEI), or primary immunodeficiencies, may be associated with a potential risk factor for early-onset gastrointestinal (GI) cancer. METHODS: We systematically reviewed all cases with clinical diagnoses of both an IEI and a GI cancer in three databases (MEDLINE, SCOPUS, and EMBASE). In total, 76 publications satisfying our inclusion criteria were identified, and data for 149 cases were analyzed. We also searched our institutional cancer registry for such cases. RESULTS: We identified 149 patients with both an IEI and a GI cancer, 95 presented gastric cancer, 13 small bowel cancer, 35 colorectal cancer, and 6 had an unspecified cancer or cancer at another site. Gastric and colon adenocarcinomas were the most common. For both gastric and colorectal cancers, age at onset was significantly earlier in patients with IEIs than in the general population, based on the SEER database. Common variable immunodeficiency (CVID) was the most common IEI associated with gastrointestinal cancer. About 12% of patients had molecular genetic diagnoses, the three most frequently implicated genes being ATM, CARMIL2, and CTLA4. Impaired humoral immunity and Epstein-Barr virus (EBV) infection were frequently reported as factors potentially underlying early-onset GI cancers in patients with IEIs. We identified one patient with CVID and early-onset gastric adenocarcinoma, recurrent diarrhea, and gastrointestinal CMV infection from a retrospective survey. CONCLUSION: Patients with IEIs should be considered at risk of early-onset GI cancers and should therefore undergo cancer screening at an earlier age.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Neoplasias Gastrointestinales , Neoplasias Gástricas , Infecciones por Virus de Epstein-Barr/complicaciones , Neoplasias Gastrointestinales/epidemiología , Herpesvirus Humano 4 , Humanos , Inmunogenética , Estudios Retrospectivos , Neoplasias Gástricas/epidemiología
13.
BMC Psychiatry ; 22(1): 449, 2022 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-35790932

RESUMEN

BACKGROUND: The objective of this study was to explore the stigma and related influencing factors in individuals with chronic insomnia disorder (CID). METHODS: A total of 70 CID patients and 70 healthy controls (CON) were enrolled in the study. All subjects completed the assessments of sleep, emotion, and cognition. Their stigma and life quality were measured using the Chronic Stigma Scale and the 36-Item Short-Form Health Survey (SF-36). RESULTS: The ratio of individuals with stigma was significantly different between CID and CON groups (C2 = 35.6, p < 0.001). Compared with the CON group, the CID group had higher scores for total stigma (U = 662.0, p < 0.001), internalized stigma (U = 593.0, p < 0.001), enacted stigma (U = 1568.0, p < 0.001), PSQI (U = 2485.0, p < 0.001) and HAMD-17 (U = 69.5, p < 0.001) as well as lower scores for MoCA-C (U = 3997.5, p < 0.001) and most items of SF-36. Partial correlation analysis showed that different items of the Chronic Stigma Scale were positively correlated with illness duration, PSQI and HAMD-17 scores, while negatively correlated with one or more items of the SF-36. Multivariate regression analysis showed that illness duration and the Mental Health domain of the SF-36 were independent risk factors for one or more items of stigma in CID patients. CONCLUSION: Patients with CID have an increased risk of stigma. Moreover, illness duration and Mental Health may be primary factors related to stigma.


Asunto(s)
Trastornos del Inicio y del Mantenimiento del Sueño , Emociones , Humanos , Calidad de Vida/psicología , Estigma Social , Encuestas y Cuestionarios
14.
J Chem Phys ; 156(7): 074701, 2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-35183079

RESUMEN

We theoretically investigate the high-order harmonic generation (HHG) of the monolayer hexagonal boron nitride by two-color laser pulses, based on the ab initio time-dependent density-functional theory. We find that the waveform of the two-color laser field can dramatically control the harmonic spectrum. The two-color laser field can enhance the harmonic radiation more efficiently than the monochromatic pulse laser with the same incident energy. We investigate the influence of incident laser pulse parameters on the harmonic radiation, such as the relative phase of the two-color field, the amplitude ratio between component electric fields, and the laser orientation. We show that the HHG spectrum is controlled by both the electric field and the vector potential. The electronic band structure and the laser-matter energy transfer play an important role in determining the laser polarization for optimal HHG in the hBN crystal. Our work supplies a scheme to manipulate HHGs in two-dimensional materials and provides a potential methodology for the generation of intense extreme-ultraviolet pulses.

15.
Proc Natl Acad Sci U S A ; 116(33): 16463-16472, 2019 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-31346092

RESUMEN

Heterozygous in-frame mutations in coding regions of human STAT3 underlie the only known autosomal dominant form of hyper IgE syndrome (AD HIES). About 5% of familial cases remain unexplained. The mutant proteins are loss-of-function and dominant-negative when tested following overproduction in recipient cells. However, the production of mutant proteins has not been detected and quantified in the cells of heterozygous patients. We report a deep intronic heterozygous STAT3 mutation, c.1282-89C>T, in 7 relatives with AD HIES. This mutation creates a new exon in the STAT3 complementary DNA, which, when overexpressed, generates a mutant STAT3 protein (D427ins17) that is loss-of-function and dominant-negative in terms of tyrosine phosphorylation, DNA binding, and transcriptional activity. In immortalized B cells from these patients, the D427ins17 protein was 2 kDa larger and 4-fold less abundant than wild-type STAT3, on mass spectrometry. The patients' primary B and T lymphocytes responded poorly to STAT3-dependent cytokines. These findings are reminiscent of the impaired responses of leukocytes from other patients with AD HIES due to typical STAT3 coding mutations, providing further evidence for the dominance of the mutant intronic allele. These findings highlight the importance of sequencing STAT3 introns in patients with HIES without candidate variants in coding regions and essential splice sites. They also show that AD HIES-causing STAT3 mutant alleles can be dominant-negative even if the encoded protein is produced in significantly smaller amounts than wild-type STAT3.


Asunto(s)
Proteínas de Unión al ADN/genética , Síndrome de Job/genética , Sitios de Empalme de ARN/genética , Factor de Transcripción STAT3/genética , Adulto , Alelos , Linfocitos B/metabolismo , Linfocitos B/patología , Preescolar , Exones/genética , Femenino , Regulación de la Expresión Génica/genética , Heterocigoto , Humanos , Síndrome de Job/patología , Mutación con Pérdida de Función/genética , Masculino , Persona de Mediana Edad , Linfocitos T/metabolismo , Linfocitos T/patología
16.
Nano Lett ; 21(18): 7815-7822, 2021 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-34491064

RESUMEN

Chemical etching can create novel structures inaccessible by growth and provide complementary understanding on the growth mechanisms of complex nanostructures. Screw dislocation-driven growth influences the layer stackings of transition metal dichalcogenides (MX2) resulting in complex spiral morphologies. Herein, we experimentally and theoretically study the etching of screw dislocated WS2 and WSe2 nanostructures using H2O2 etchant. The kinetic Wulff constructions and Monte Carlo simulations establish the etching principles of single MX2 layers. Atomic force microscopy characterization reveals diverse etching morphology evolution behaviors around the dislocation cores and along the exterior edges, including triangular, hexagonal, or truncated hexagonal holes and smooth or rough edges. These behaviors are influenced by the edge orientations, layer stackings, and the strain of screw dislocations. Ab initio calculation and kinetic Monte Carlo simulations support the experimental observations and provide further mechanistic insights. This knowledge can help one to understand more complex structures created by screw dislocations through etching.


Asunto(s)
Nanoestructuras , Elementos de Transición , Tornillos Óseos , Peróxido de Hidrógeno , Microscopía de Fuerza Atómica
17.
Genet Med ; 23(3): 576-580, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33060835

RESUMEN

PURPOSE: Rare genetic conditions like Down syndrome (DS) are historically understudied. Infection is a leading cause of mortality in DS, along with cardiac anomalies. Currently, it is unknown how the COVID-19 pandemic affects individuals with DS. Herein, we report an analysis of individuals with DS who were hospitalized with COVID-19 in New York, New York, USA. METHODS: In this retrospective, dual-center study of 7246 patients hospitalized with COVID-19, we analyzed all patients with DS admitted in the Mount Sinai Health System and Columbia University Irving Medical Center. We assessed hospitalization rates, clinical characteristics, and outcomes. RESULTS: We identified 12 patients with DS. Hospitalized individuals with DS are on average ten years younger than patients without DS. Patients with DS have more severe disease than controls, particularly an increased incidence of sepsis and mechanical ventilation. CONCLUSION: We demonstrate that individuals with DS who are hospitalized with COVID-19 are younger than their non-DS counterparts, and that they have more severe disease than age-matched controls. We conclude that particular care should be considered for both the prevention and treatment of COVID-19 in these patients.


Asunto(s)
COVID-19/patología , Síndrome de Down , Adulto , Comorbilidad , Síndrome de Down/complicaciones , Femenino , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , New York/epidemiología , Pandemias , Estudios Retrospectivos
18.
Hepatology ; 71(6): 2005-2022, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31541481

RESUMEN

BACKGROUND AND AIMS: Cancer cell survival depends on the balance between reactive oxygen species production and scavenging, which is regulated primarily by NRF2 during tumorigenesis. Here, we demonstrate that deletion of RBP5-mediating protein (RMP) in an autonomous mouse model of intrahepatic cholangiocarcinoma (ICC) delays tumor progression. APPROACH AND RESULTS: RMP-overexpressing tumor cells exhibited enhanced tolerance to oxidative stress and apoptosis. Mechanistically, RMP competes with NRF2 for binding to the Kelch domain of KEAP1 (Kelch-like ECH-associated protein 1) through the E**E motif, leading to decreased NRF2 degradation via ubiquitination, thus increasing NRF2 nuclear translocation and downstream transactivation of antioxidant genes. This RMP-KEAP1-NRF2 axis promotes ICC tumorigenesis, metastasis, and drug resistance. Consistent with these findings, the RMP level in human ICC is positively correlated with the protein level of NRF2 and is associated with poor prognosis. CONCLUSION: These findings reveal that RMP is involved in the oxidative stress defense program and could be exploited for targeted cancer therapies.


Asunto(s)
Carcinogénesis , Colangiocarcinoma/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Proteínas Represoras/metabolismo , Animales , Apoptosis , Carcinogénesis/efectos de los fármacos , Carcinogénesis/metabolismo , Línea Celular , Transformación Celular Neoplásica/metabolismo , Colangiocarcinoma/patología , Resistencia a Antineoplásicos , Humanos , Ratones , Estrés Oxidativo
19.
J Integr Plant Biol ; 63(12): 2123-2135, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34655280

RESUMEN

Pear has an S-RNase-based gametophytic self-incompatibility (SI) system. Nuclear DNA degradation is a typical feature of incompatible pollen tube death, and is among the many physiological functions of vacuoles. However, the specific changes that occur in vacuoles, as well as the associated regulatory mechanism in pear SI, are currently unclear. Although research in tobacco has shown that decreased activity of diacylglycerol kinase (DGK) results in the morphological change of pollen tube vacuole, whether DGK regulates the pollen tube vacuole of tree plants and whether it occurs in SI response, is currently unclear. We found that DGK activity is essential for pear pollen tube growth, and DGK4 regulates pollen tube vacuole morphology following its high expression and deposition at the tip and shank edge of the pollen tube of pear. Specifically, incompatible S-RNase may induce cytoplasmic acidification of the pollen tube by inhibiting V-ATPase V0 domain a1 subunit gene expression as early as 30 min after treatment, when the pollen tube is still alive. Cytoplasmic acidification induced by incompatible S-RNase results in reduced DGK4 abundance and deposition, leading to morphological change of the vacuole and fragmentation of nuclear DNA, which indicates that DGK4 is a key factor in pear SI response.


Asunto(s)
Pyrus , ADN/metabolismo , Diacilglicerol Quinasa/genética , Diacilglicerol Quinasa/metabolismo , Concentración de Iones de Hidrógeno , Tubo Polínico/metabolismo , Pyrus/genética , Pyrus/metabolismo , Vacuolas/metabolismo
20.
Hum Mol Genet ; 27(22): 3919-3935, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-31222290

RESUMEN

Mendelian susceptibility to mycobacterial disease (MSMD) is characterized by clinical disease caused by weakly virulent mycobacteria, such as environmental mycobacteria and Bacillus Calmette-Guérin vaccines, in otherwise healthy individuals. All known genetic etiologies disrupt interferon (IFN)-γ immunity. Germline bi-allelic mutations of IFNGR2 can underlie partial or complete forms of IFN-γ receptor 2 (IFN-γR2) deficiency. Patients with partial IFN-γR2 deficiency express a dysfunctional molecule on the cell surface. We studied three patients with MSMD from two unrelated kindreds from Turkey (P1, P2) and India (P3), by whole-exome sequencing. P1 and P2 are homozygous for a mutation of the initiation codon(c.1A>G) of IFNGR2, whereas P3 is homozygous for a mutation of the second codon (c.4delC). Overexpressed mutant alleles produce small amounts of full-length IFN-γR2 resulting in an impaired, but not abolished, response to IFN-γ. Moreover, SV40-fibroblasts of P1 and P2 responded weakly to IFN-γ, and Epstein Barr virus-transformed B cells had a barely detectable response to IFN-γ. Studies in patients' primary T cells and monocyte-derived macrophages yielded similar results. The residual expression of IFN-γR2 protein of normal molecular weight and function is due to the initiation of translation between the second and ninth non-AUG codons. We thus describe mutations of the first and second codons of IFNGR2, which define a new form of partial recessive IFN-γR2 deficiency. Residual levels of IFN-γ signaling were very low, accounting for the more severe clinical phenotype of these patients with residual expression levels of normally functional surface receptors than of patients with partial recessive IFN-γR2 deficiency due to surface-expressed dysfunctional receptors, whose residual levels of IFN-γ signaling were higher.


Asunto(s)
Alelos , Codón Iniciador , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Homocigoto , Infecciones por Mycobacterium/genética , Receptores de Interferón/genética , Niño , Preescolar , Femenino , Humanos , India , Lactante , Recién Nacido , Masculino , Turquía , Secuenciación del Exoma
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