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1.
Immunity ; 54(6): 1276-1289.e6, 2021 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-33836142

RESUMEN

Interaction of the SARS-CoV-2 Spike receptor binding domain (RBD) with the receptor ACE2 on host cells is essential for viral entry. RBD is the dominant target for neutralizing antibodies, and several neutralizing epitopes on RBD have been molecularly characterized. Analysis of circulating SARS-CoV-2 variants has revealed mutations arising in the RBD, N-terminal domain (NTD) and S2 subunits of Spike. To understand how these mutations affect Spike antigenicity, we isolated and characterized >100 monoclonal antibodies targeting epitopes on RBD, NTD, and S2 from SARS-CoV-2-infected individuals. Approximately 45% showed neutralizing activity, of which ∼20% were NTD specific. NTD-specific antibodies formed two distinct groups: the first was highly potent against infectious virus, whereas the second was less potent and displayed glycan-dependant neutralization activity. Mutations present in B.1.1.7 Spike frequently conferred neutralization resistance to NTD-specific antibodies. This work demonstrates that neutralizing antibodies targeting subdominant epitopes should be considered when investigating antigenic drift in emerging variants.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Anticuerpos Antivirales/inmunología , COVID-19/inmunología , COVID-19/virología , Epítopos/inmunología , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Enzima Convertidora de Angiotensina 2/química , Enzima Convertidora de Angiotensina 2/metabolismo , Anticuerpos Monoclonales/química , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/química , COVID-19/diagnóstico , Reacciones Cruzadas/inmunología , Epítopos/química , Epítopos/genética , Humanos , Modelos Moleculares , Mutación , Pruebas de Neutralización , Unión Proteica/inmunología , Conformación Proteica , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Relación Estructura-Actividad
2.
Proc Natl Acad Sci U S A ; 121(34): e2320257121, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39150784

RESUMEN

Lysosomal degradation pathways coordinate the clearance of superfluous and damaged cellular components. Compromised lysosomal degradation is a hallmark of many degenerative diseases, including lysosomal storage diseases (LSDs), which are caused by loss-of-function mutations within both alleles of a lysosomal hydrolase, leading to lysosomal substrate accumulation. Gaucher's disease, characterized by <15% of normal glucocerebrosidase function, is the most common LSD and is a prominent risk factor for developing Parkinson's disease. Here, we show that either of two structurally distinct small molecules that modulate PIKfyve activity, identified in a high-throughput cellular lipid droplet clearance screen, can improve glucocerebrosidase function in Gaucher patient-derived fibroblasts through an MiT/TFE transcription factor that promotes lysosomal gene translation. An integrated stress response (ISR) antagonist used in combination with a PIKfyve modulator further improves cellular glucocerebrosidase activity, likely because ISR signaling appears to also be slightly activated by treatment by either small molecule at the higher doses employed. This strategy of combining a PIKfyve modulator with an ISR inhibitor improves mutant lysosomal hydrolase function in cellular models of additional LSD.


Asunto(s)
Fibroblastos , Glucosilceramidasa , Enfermedades por Almacenamiento Lisosomal , Lisosomas , Fosfatidilinositol 3-Quinasas , Humanos , Fosfatidilinositol 3-Quinasas/metabolismo , Lisosomas/metabolismo , Lisosomas/efectos de los fármacos , Glucosilceramidasa/metabolismo , Glucosilceramidasa/genética , Fibroblastos/metabolismo , Fibroblastos/efectos de los fármacos , Enfermedades por Almacenamiento Lisosomal/tratamiento farmacológico , Enfermedades por Almacenamiento Lisosomal/genética , Enfermedades por Almacenamiento Lisosomal/metabolismo , Enfermedad de Gaucher/tratamiento farmacológico , Enfermedad de Gaucher/genética , Enfermedad de Gaucher/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacología
3.
Plant Physiol ; 194(2): 787-804, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-37815230

RESUMEN

Root development influences plant responses to environmental conditions, and well-developed rooting enhances plant survival under abiotic stress. However, the molecular and genetic mechanisms underlying root development and abiotic stress tolerance in plants remain unclear. In this study, we identified the MYB transcription factor-encoding gene IbMYB73 by cDNA-amplified fragment length polymorphism and RNA-seq analyses. IbMYB73 expression was greatly suppressed under abiotic stress in the roots of the salt-tolerant sweet potato (Ipomoea batatas) line ND98, and its promoter activity in roots was significantly reduced by abscisic acid (ABA), NaCl, and mannitol treatments. Overexpression of IbMYB73 significantly inhibited adventitious root growth and abiotic stress tolerance, whereas IbMYB73-RNAi plants displayed the opposite pattern. IbMYB73 influenced the transcription of genes involved in the ABA pathway. Furthermore, IbMYB73 formed homodimers and activated the transcription of ABA-responsive protein IbGER5 by binding to an MYB binding sites I motif in its promoter. IbGER5 overexpression significantly inhibited adventitious root growth and abiotic stress tolerance concomitantly with a reduction in ABA content, while IbGER5-RNAi plants showed the opposite effect. Collectively, our results demonstrated that the IbMYB73-IbGER5 module regulates ABA-dependent adventitious root growth and abiotic stress tolerance in sweet potato, which provides candidate genes for the development of elite crop varieties with well-developed root-mediated abiotic stress tolerance.


Asunto(s)
Ácido Abscísico , Ipomoea batatas , Ácido Abscísico/farmacología , Ácido Abscísico/metabolismo , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Estrés Fisiológico/fisiología , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
4.
Proc Natl Acad Sci U S A ; 119(34): e2201541119, 2022 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-35943978

RESUMEN

Whereas pathogen-specific T and B cells are a primary focus of interest during infectious disease, we have used COVID-19 to ask whether their emergence comes at a cost of broader B cell and T cell repertoire disruption. We applied a genomic DNA-based approach to concurrently study the immunoglobulin-heavy (IGH) and T cell receptor (TCR) ß and δ chain loci of 95 individuals. Our approach detected anticipated repertoire focusing for the IGH repertoire, including expansions of clusters of related sequences temporally aligned with SARS-CoV-2-specific seroconversion, and enrichment of some shared SARS-CoV-2-associated sequences. No significant age-related or disease severity-related deficiencies were noted for the IGH repertoire. By contrast, whereas focusing occurred at the TCRß and TCRδ loci, including some TCRß sequence-sharing, disruptive repertoire narrowing was almost entirely limited to many patients aged older than 50 y. By temporarily reducing T cell diversity and by risking expansions of nonbeneficial T cells, these traits may constitute an age-related risk factor for COVID-19, including a vulnerability to new variants for which T cells may provide key protection.


Asunto(s)
Inmunidad Adaptativa , COVID-19 , Cadenas Pesadas de Inmunoglobulina , Receptores de Antígenos de Linfocitos T alfa-beta , Receptores de Antígenos de Linfocitos T , SARS-CoV-2 , Inmunidad Adaptativa/genética , Anciano , Linfocitos B/inmunología , COVID-19/genética , COVID-19/inmunología , Sitios Genéticos , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T alfa-beta/genética , SARS-CoV-2/inmunología , Seroconversión , Linfocitos T/inmunología
5.
Nano Lett ; 24(11): 3541-3547, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38451854

RESUMEN

Two-dimensional (2D) multiferroic materials have widespread application prospects in facilitating the integration and miniaturization of nanodevices. However, the magnetic, ferroelectric, and ferrovalley properties in one 2D material are rarely coupled. Here, we propose a mechanism for manipulating magnetism, ferroelectric, and valley polarization by interlayer sliding in a 2D bilayer material. Monolayer GdI2 is a ferromagnetic semiconductor with a valley polarization of up to 155.5 meV. More interestingly, the magnetism and valley polarization of bilayer GdI2 can be strongly coupled by sliding ferroelectricity, making these tunable and reversible. In addition, we uncover the microscopic mechanism of the magnetic phase transition by a spin Hamiltonian and electron hopping between layers. Our findings offer a new direction for investigating 2D multiferroic devices with implications for next-generation electronic, valleytronic, and spintronic devices.

6.
Nano Lett ; 24(1): 441-449, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38109494

RESUMEN

Conjugated polymer films are promising in wearable X-ray detection. However, achieving optimal film microstructure possessing good electrical and detection performance under large deformation via scalable printing remains challenging. Herein, we report bar-coated high-performance stretchable films based on a conjugated polymer P(TDPP-Se) and elastomer SEBS blend by optimizing the solution-processing conditions. The moderate preaggregation in solution and prolonged growth dynamics from a solvent mixture with limited dissolving capacity is critical to forming aligned P(TDPP-Se) chains/crystalline nanofibers in the SEBS phase with enhanced π-π stacking for charge transport and stress dissipation. The film shows a large elongation at break of >400% and high mobilities of 5.29 cm2 V-1 s-1 at 0% strain and 1.66 cm2 V-1 s-1 over 500 stretch-release cycles at 50% strain, enabling good X-ray imaging with a high sensitivity of 1501.52 µC Gyair-1 cm-2. Our work provides a morphology control strategy toward high-performance conjugated polymer film-based stretchable electronics.

7.
Magn Reson Med ; 92(2): 532-542, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38650080

RESUMEN

PURPOSE: CEST can image macromolecules/compounds via detecting chemical exchange between labile protons and bulk water. B1 field inhomogeneity impairs CEST quantification. Conventional B1 inhomogeneity correction methods depend on interpolation algorithms, B1 choices, acquisition number or calibration curves, making reliable correction challenging. This study proposed a novel B1 inhomogeneity correction method based on a direct saturation (DS) removed omega plot model. METHODS: Four healthy volunteers underwent B1 field mapping and CEST imaging under four nominal B1 levels of 0.75, 1.0, 1.5, and 2.0 µT at 5T. DS was resolved using a multi-pool Lorentzian model and removed from respective Z spectrum. Residual spectral signals were used to construct the omega plot as a linear function of 1/ B 1 2 $$ {B}_1^2 $$ , from which corrected signals at nominal B1 levels were calculated. Routine asymmetry analysis was conducted to quantify amide proton transfer (APT) effect. Its distribution across white matter was compared before and after B1 inhomogeneity correction and also with the conventional interpolation approach. RESULTS: B1 inhomogeneity yielded conspicuous artifact on APT images. Such artifact was mitigated by the proposed method. Homogeneous APT maps were shown with SD consistently smaller than that before B1 inhomogeneity correction and the interpolation method. Moreover, B1 inhomogeneity correction from two and four CEST acquisitions yielded similar results, superior over the interpolation method that derived inconsistent APT contrasts among different B1 choices. CONCLUSION: The proposed method enables reliable B1 inhomogeneity correction from at least two CEST acquisitions, providing an effective way to improve quantitative CEST MRI.


Asunto(s)
Algoritmos , Artefactos , Voluntarios Sanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Humanos , Imagen por Resonancia Magnética/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Adulto , Masculino , Femenino , Encéfalo/diagnóstico por imagen , Protones , Sustancia Blanca/diagnóstico por imagen , Fantasmas de Imagen
8.
NMR Biomed ; 37(5): e5099, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38185878

RESUMEN

Magnetic resonance Z-spectral imaging (ZSI) has emerged as a new approach to measure fat fraction (FF). However, its feasibility for fat spectral imaging remains to be elucidated. In this study, a single-slice ZSI sequence dedicated to fat spectral imaging was designed, and its capability for fatty acid characterization was investigated on peanut oil samples, a multiple-vial fat-water phantom with varied oil volumes, and vertebral body marrow in healthy volunteers and osteoporosis patients at 3 T. The peanut oil spectrum was also recorded with a 400-MHz NMR spectrometer. A Gaussian-Lorentzian sum model was used to resolve water and six fat signals of the pure oil sample or four fat signals of the fat-water phantom or vertebral bone marrow from Z spectra. Fat peak amplitudes were normalized to the total peak amplitude of water and all fat signals. Normalized fat peak amplitudes and FF were quantified and compared among vials of the fat-water phantom or between healthy volunteers and osteoporosis patients. An unpaired student's t-test and Pearson's correlation were conducted, with p less than 0.05 considered statistically significant. The results showed that the peanut oil spectra measured with the ZSI technique were in line with respective NMR spectra, with amplitudes of the six fat signal peaks significantly correlated between the two methods (y = x + 0.001, r = 0.996, p < 0.001 under a repetition time of 1.6 s; and y = 1.026x - 0.003, r = 0.996, p < 0.001 under a repetition time of 3.1 s). Moreover, ZSI-measured FF exhibited a significant correlation with prepared oil volumes (y = 0.876x + 1.290, r = 0.996, p < 0.001). The osteoporosis patients showed significantly higher normalized fat peak amplitudes and FF in the L4 vertebral body marrow than the healthy volunteers (all p < 0.01). In summary, the designed ZSI sequence is feasible for fatty acid characterization, and has the potential to facilitate the diagnosis and evaluation of diseases associated with fat alterations at 3 T.


Asunto(s)
Médula Ósea , Osteoporosis , Humanos , Médula Ósea/diagnóstico por imagen , Médula Ósea/patología , Aceite de Cacahuete , Imagen por Resonancia Magnética/métodos , Osteoporosis/diagnóstico por imagen , Osteoporosis/patología , Espectroscopía de Resonancia Magnética , Agua , Tejido Adiposo/diagnóstico por imagen , Tejido Adiposo/patología
9.
J Magn Reson Imaging ; 59(1): 201-208, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37246769

RESUMEN

BACKGROUND: pH MRI may provide useful information to evaluate metabolic disruption following ischemia. Radiofrequency amplitude-based creatine chemical exchange saturation transfer (CrCEST) ratiometric MRI is pH-sensitive, which could but has not been explored to examine muscle ischemia. PURPOSE: To investigate skeletal muscle energy metabolism alterations with CrCEST ratiometric MRI. STUDY TYPE: Prospective. ANIMAL MODEL: Seven adult New Zealand rabbits with ipsilateral hindlimb muscle ischemia. FIELD STRENGTH/SEQUENCE: 3 T/two MRI scans, including MRA and CEST imaging, were performed under two B1 amplitudes of 0.5 and 1.25 µT after 2 hours of hindlimb muscle ischemia and 1 hour of reperfusion recovery, respectively. ASSESSMENT: CEST effects of two energy metabolites of creatine and phosphocreatine (PCrCEST) were resolved with the multipool Lorentzian fitting approach. The pixel-wise CrCEST ratio was quantified by calculating the ratio of the resolved CrCEST peaks under a B1 amplitude of 1.25 µT to those under 0.5 µT in the entire muscle. STATISTICAL TESTS: One-way ANOVA and Pearson's correlation. P < 0.05 was considered statistically significant. RESULTS: MRA images confirmed the blood flow loss and restoration in the ischemic hindlimb at the ischemia and recovery phases, respectively. Ischemic muscles exhibited a significant decrease of PCr at the ischemia (under both B1 amplitudes) and recovery phases (under B1 amplitude of 0.5 µT) and significantly increased CrCEST from normal tissues at both phases (under both B1 levels). Specifically, CrCEST decreased, and PCrCEST increased with the CrCEST ratio. Significantly strong correlations were observed among the CrCEST ratio, and CrCEST and PCrCEST under both B1 levels (r > 0.80). DATA CONCLUSION: The CrCEST ratio altered substantially with muscle pathological states and was closely related to CEST effects of energy metabolites of Cr and PCr, suggesting that the pH-sensitive CrCEST ratiometric MRI is feasible to evaluate muscle injuries at the metabolic level. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY STAGE: 1.


Asunto(s)
Creatina , Imagen por Resonancia Magnética , Conejos , Animales , Creatina/metabolismo , Proyectos Piloto , Estudios Prospectivos , Imagen por Resonancia Magnética/métodos , Fosfocreatina/metabolismo , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/metabolismo , Metabolismo Energético , Isquemia
10.
J Magn Reson Imaging ; 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38236785

RESUMEN

BACKGROUND: Quantitative in-situ pH mapping of gliomas is important for therapeutic interventions, given its significant association with tumor progression, invasion, and metastasis. Although chemical exchange saturation transfer (CEST) offers a noninvasive way for pH imaging based on the pH-dependent exchange rate (ksw ), the reliable quantification of ksw in glioma remains constrained due to technical challenges. PURPOSE: To quantify the pH of gliomas by measuring the proton exchange rate through optimized omega plot analysis. STUDY TYPE: Prospective. PHANTOMS/ANIMAL MODEL/SUBJECTS: Creatine and murine brain lysates phantoms, six rats with glioma xenograft model, and three patients with World Health Organization grade 2-4 gliomas. FIELD STRENGTH/SEQUENCE: 11.7 T, 7.0 T, CEST imaging, T2 -weighted (T2 W) imaging, and T1 -mapping. ASSESSMENT: Omega plot analysis, quasi-steady-state (QUASS) analysis, multi-pool Lorentzian fitting, amine and amide concentration-independent detection, pH enhanced method with the combination of amide and guanidyl (pHenh ), and magnetization transfer ratio (MTR) were utilized for pH metric quantification. The clinical outcomes were determined through radiologic follow-up and histopathological analysis. STATISTICAL TESTS: Mann-Whitney U test was performed to compare glioma with normal tissue, and Pearson's correlation analysis was used to assess the relationship between ksw and other parameters. RESULTS: In vitro experiments reveal that the determined ksw at 2 ppm increases exponentially with pH (creatine phantoms: ksw = 106 + 0.147 × 10(pH-4.198) ; lysates: ksw = 185.1 + 0.101 × 10(pH-3.914) ). Omega plot analysis exhibits a linear correlation between 1/MTRRex and 1/ω1 2 in the glioma xenografts (R2 > 0.98) and glioma patients (R2 > 0.99). The exchange rate in the rat glioma decreases compared to the contralateral normal tissue (349.46 ± 30.40 s-1 vs. 403.54 ± 51.01 s-1 , P = 0.025), while keeping independence from changes in concentration (r = 0.5037, P = 0.095). Similar pattern was observed in human data. DATA CONCLUSION: Utilizing QUASS-based, spillover-, and MT-corrected omega plot analysis for the measurement of exchange rates, offers a feasible method for quantifying pH within glioma. LEVEL OF EVIDENCE: NA TECHNICAL EFFICACY: Stage 1.

11.
FASEB J ; 37(1): e22716, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36527390

RESUMEN

Non-alcoholic fatty liver disease (NAFLD) is a major health problem in Western countries and has become the most common cause of chronic liver disease. Although NAFLD is closely associated with obesity, inflammation, and insulin resistance, its pathogenesis remains unclear. The disease begins with excessive accumulation of triglycerides in the liver, which in turn leads to liver cell damage, steatosis, inflammation, and so on. P38γ is one of the four isoforms of P38 mitogen-activated protein kinases (P38 MAPKs) that contributes to inflammation in different diseases. In this research, we investigated the role of P38γ in NAFLD. In vivo, a NAFLD model was established by feeding C57BL/6J mice with a methionine- and choline-deficient (MCD) diet and adeno-associated virus (AAV9-shRNA-P38γ) was injected into C57BL/6J mice by tail vein for knockdown P38γ. The results indicated that the expression level of P38γ was upregulated in MCD-fed mice. Furthermore, the downregulation of P38γ significantly attenuated liver injury and lipid accumulation in mice. In vitro, mouse hepatocytes AML-12 were treated with free fatty acid (FFA). We found that P38γ was obviously increased in FFA-treated AML-12 cells, whereas knockdown of P38γ significantly suppressed lipid accumulation in FFA-treated AML-12 cells. Furthermore, P38γ regulated the Janus Kinase-Signal transducers and activators of transcription (JAK-STAT) signaling pathway. Inhibition of P38γ can inhibit the JAK-STAT signaling pathway, thereby inhibiting lipid accumulation in FFA-treated AML-12 cells. In conclusion, our results suggest that targeting P38γ contributes to the suppression of lipid accumulation in fatty liver disease.


Asunto(s)
Leucemia Mieloide Aguda , Enfermedad del Hígado Graso no Alcohólico , Ratones , Animales , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Metabolismo de los Lípidos , Quinasas Janus/metabolismo , Dieta Alta en Grasa , Ratones Endogámicos C57BL , Hígado/metabolismo , Transducción de Señal , Ácidos Grasos no Esterificados/metabolismo , Inflamación/metabolismo , Metionina/farmacología , Metionina/metabolismo , Leucemia Mieloide Aguda/metabolismo
12.
Cell Biol Toxicol ; 40(1): 12, 2024 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-38340268

RESUMEN

V-type immunoglobulin domain-containing suppressor of T-cell activation (VISTA), a novel negative checkpoint regulator, plays an essential role in allergic pulmonary inflammation in mice. Treatment with a VISTA agonistic antibody could significantly improve asthma symptoms. Thus, for allergic asthma treatment, VISTA targeting may be a compelling approach. In this study, we examined the functional mechanism of VISTA in allergic pulmonary inflammation and screened the FDA-approved drugs for VISTA agonists. By using mass cytometry (CyTOF), we found that VISTA deficiency primarily increased lung macrophage infiltration in the OVA-induced asthma model, accompanied by an increased proportion of M1 macrophages (CD11b+F4/80+CD86+) and a decreased proportion of M2 macrophages (CD11b+F4/80+CD206+). Further in vitro studies showed that VISTA deficiency promoted M1 polarization and inhibited M2 polarization of bone marrow-derived macrophages (BMDMs). Importantly, we discovered baloxavir marboxil (BXM) as a VISTA agonist by virtual screening of FDA-approved drugs. The surface plasmon resonance (SPR) assays revealed that BXM (KD = 1.07 µM) as well as its active form, baloxavir acid (BXA) (KD = 0.21 µM), could directly bind to VISTA with high affinity. Notably, treatment with BXM significantly ameliorated asthma symptoms, including less lung inflammation, mucus secretion, and the generation of Th2 cytokines (IL-5, IL-13, and IL-4), which were dramatically attenuated by anti-VISTA monoclonal antibody treatment. BXM administration also reduced the pulmonary infiltration of M1 macrophages and raised M2 macrophages. Collectively, our study indicates that VISTA regulates pulmonary inflammation in allergic asthma by regulating macrophage polarization and baloxavir marboxil, and an old drug might be a new treatment for allergic asthma through targeting VISTA.


Asunto(s)
Asma , Dibenzotiepinas , Neumonía , Piridonas , Triazinas , Animales , Ratones , Asma/tratamiento farmacológico , Asma/metabolismo , Morfolinas/farmacología , Morfolinas/uso terapéutico
13.
Macromol Rapid Commun ; 45(1): e2300240, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37289949

RESUMEN

The physical blending of high-mobility conjugated polymers with ductile elastomers provides a simple way to realize high-performance stretchable films. However, how to control the morphology of the conjugated polymer and elastomer blend film and its response to mechanical fracture processes during stretching are not well understood. Herein, a sandwich structure is constructed in the blend film based on a conjugated polymer poly[(5-fluoro-2,1,3-benzothiadiazole-4,7-diyl)(4,4-dihexadecyl-4H-cyclopenta[2,1-b:3,4-b″]dithiophene-2,6-diyl)(6-fluoro-2,1,3-benzothiadiazole-4,7-diyl)(4,4-dihexadecyl-4H-cyclopenta[2,1-b:3,4-b″]dithiophene-2,6-diyl)] (PCDTFBT) and an elastomer polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (SEBS). The sandwich structure is composed of a PCDTFBT:SEBS mixed layer laminated with a PCDTFBT-rich layer at both the top and bottom surfaces. During stretching, the external strain energy can be effectively dissipated by the deformation of the crystalline PCDTFBT domains and amorphous SEBS phases and the recrystallization of the PCDTFBT chains. This endows the blend film with excellent ductility, with a large crack onset strain exceeding 1100%, and minimized the electrical degradation of the blend film at a large strain. This study indicates that the electrical and mechanical performance of conjugated polymer/elastomer blend films can be improved by manipulating their microstructure.


Asunto(s)
Polímeros , Tiadiazoles , Elastómeros/química , Polímeros/química , Poliestirenos , Tiadiazoles/química , Tiofenos/química
14.
Surg Endosc ; 38(5): 2719-2725, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38532050

RESUMEN

BACKGROUND: Revisional bariatric surgery after an index adjustable gastric band (AGB) may be indicated to remedy weight relapse or band-related complications. We examined outcomes five years following revision from AGB to laparoscopic sleeve gastrectomy (AGB-LSG) or to Roux-en-Y gastric bypass (AGB-RYGB). METHODS: We conducted a retrospective review to identify patients (men and women, age 18-80) who underwent one revisional bariatric procedure with AGB as the index procedure at two medical centers in our healthcare system between January 2012 and February 2017. We only included patients with a pre-revision BMI > 30 kg/m2 for whom 5-year follow-up data were available. We compared 5-year weight loss and remission of comorbidities in patients undergoing AGB-LSG and AGB-RYGB conversion. RESULTS: A total of 114 patients met inclusion criteria (65 AGB-LSG, 49 AGB-RYGB). At 5-year post-revision, percent total weight loss (3.4% vs 19.9%; p < 0.001), percent excess weight loss (7.0% vs 50.8%; p < 0.001) and decrease in BMI (1.5 vs 8.8; p < 0.001) was greater in AGB-RYGB vs. AGB-LSG. No significant difference in remission or development of new comorbidities was observed. CONCLUSION: Conversion of AGB to RYGB is associated with superior intermediate-term weight loss compared to conversion of AGB to LSG. Future multicenter studies with larger sample sizes are necessary to further describe the intermediate-term outcomes of revisional bariatric surgery.


Asunto(s)
Gastrectomía , Derivación Gástrica , Gastroplastia , Obesidad Mórbida , Reoperación , Pérdida de Peso , Humanos , Femenino , Adulto , Persona de Mediana Edad , Reoperación/estadística & datos numéricos , Derivación Gástrica/métodos , Derivación Gástrica/efectos adversos , Estudios Retrospectivos , Gastrectomía/métodos , Masculino , Obesidad Mórbida/cirugía , Resultado del Tratamiento , Anciano , Gastroplastia/métodos , Adulto Joven , Adolescente , Laparoscopía/métodos , Anciano de 80 o más Años , Estudios de Seguimiento
15.
Nutr Neurosci ; : 1-11, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39046352

RESUMEN

Objective: Previous studies have suggested diet was associated with depressive symptoms. We aimed to develop and validate Dietary Depression Index (DDI) based on dietary prediction of depression in a large Chinese cancer screening cohort.Methods: In the training set (n = 2729), we developed DDI by using intake of 20 food groups derived from a food frequency questionnaire to predict depression as assessed by Patient Health Questionnaire-9 based on the reduced rank regression method. Sensitivity, specificity, positive predictive value, and negative predictive value were used to assess the performance of DDI in evaluating depression in the validation dataset (n = 1176).Results: Receiver operating characteristic analysis was constructed to determine the best cut-off value of DDI in predicting depression. In the study population, the DDI ranged from -3.126 to 1.810. The discriminative ability of DDI in predicting depression was good with the AUC of 0.799 overall, 0.794 in males and 0.808 in females. The best cut-off values of DDI for depression prediction were 0.204 overall, 0.330 in males and 0.034 in females. DDI was a validated method to assess the effects of diet on depression.Conclusion: Among individual food components in DDI, fermented vegetables, fresh vegetables, whole grains and onions were inversely associated, whereas legumes, pickled vegetables and rice were positively associated with depressive symptoms.

16.
J Math Biol ; 88(6): 72, 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38678110

RESUMEN

In this work, we formulate a random Wolbachia invasion model incorporating the effects of imperfect maternal transmission and incomplete cytoplasmic incompatibility (CI). Under constant environments, we obtain the following results: Firstly, the complete invasion equilibrium of Wolbachia does not exist, and thus the population replacement is not achievable in the case of imperfect maternal transmission; Secondly, imperfect maternal transmission or incomplete CI may obliterate bistability and backward bifurcation, which leads to the failure of Wolbachia invasion, no matter how many infected mosquitoes would be released; Thirdly, the threshold number of the infected mosquitoes to be released would increase with the decrease of the maternal transmission rate or the intensity of CI effect. In random environments, we investigate in detail the Wolbachia invasion dynamics of the random mosquito population model and establish the initial release threshold of infected mosquitoes for successful invasion of Wolbachia into the wild mosquito population. In particular, the existence and stability of invariant probability measures for the establishment and extinction of Wolbachia are determined.


Asunto(s)
Conceptos Matemáticos , Modelos Biológicos , Mosquitos Vectores , Wolbachia , Wolbachia/fisiología , Wolbachia/patogenicidad , Animales , Femenino , Mosquitos Vectores/microbiología , Dinámica Poblacional/estadística & datos numéricos , Citoplasma/microbiología , Culicidae/microbiología , Masculino , Simulación por Computador , Herencia Materna
17.
BMC Public Health ; 24(1): 821, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38491436

RESUMEN

BACKGROUND: Air pollution poses a significant health risk to the human population, especially for vulnerable groups such as the elderly, potentially discouraging their engagement in physical activity. However, there is a lack of sufficient objective and longitudinal data in current research on how air pollution affects physical activity among older adults. With these gaps, we aimed to explore the relationship between air pollution and objective measurement-based physical activity among older adults by engaging in a longitudinal study design. METHODS: A total of 184 older adults were recruited from three cities with varying levels of air quality. Mean daily minutes of physical activity were measured with 7 consecutive days of accelerometer monitoring (ActiGraph GT3X-BT). Corresponding air pollution data including daily PM2.5 (µg/m3), PM10 (µg/m3) and air quality index (AQI) were sourced from the China National Environmental Monitoring Centre at monitor locations close to older adults' addresses. Associations between air quality and physical activity were estimated using a fixed effect model, adjusting for average daytime temperature, rain, age and weight. RESULTS: AQI and PM2.5 were observed to exhibit significant, inverse, and linear associations with mean daily walk steps, minutes of light physical activity (LPA), moderate physical activity (MPA) and moderate-to-vigorous physical activity (MVPA) in the single variable models. A one-level increase in AQI corresponded to a decline in 550.04 steps (95% [CI] = -858.97, -241.10; p < 0.001), 10.43 min (95% [CI] = -17.07, -3.79; p < 0.001), 4.03 min (95% [CI] = -7.48, -0.59; p < 0.001) and 4.16 min (95% [CI] = -7.77, -0.56; p < 0.001) in daily walking steps, LPA, MPA, and MVPA, respectively. A one-level increase in PM2.5 correlated with a decline in daily walk steps, LPA, MPA and MVPA by 361.85 steps (95% [CI] = -516.53, -207.16; p < 0.001), 8.97 min (95% [CI] = -12.28, -5.66; p < 0.001), 3.73 min (95% [CI] = -5.46, -2.01; p < 0.001,) and 3.79 min (95% [CI] = -5.59, -1.98; p < 0.001), respectively. However, PM10 displayed a significant negative association exclusively with LPA, with one-level increase in PM10 resulting in a 3.7-minute reduction in LPA (95% [CI] = -6.81, -0.59, p < 0.05). CONCLUSION: Air pollution demonstrates an inverse association with physical activity levels among older adults, potentially discouraging their engagement in physical activity. Different air quality indicators may exert varying impacts on physical activity. Future studies are warranted to enhance policy interventions aimed at reducing air pollution and promoting physical activity.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Humanos , Anciano , Estudios Longitudinales , Material Particulado/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Ejercicio Físico , Monitoreo del Ambiente , Contaminantes Atmosféricos/análisis
18.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-33723066

RESUMEN

Recent evidence has linked testosterone, a major sex hormone, to selfishness in economic decision-making. Here, we aimed to investigate the neural mechanisms through which testosterone reduces generosity by combining functional MRI with pharmacological manipulation among healthy young males in a double-blind, placebo-controlled, between-subject design. After testosterone or placebo gel administration, participants performed a social discounting task in which they chose between selfish options (benefiting only the participant) and generous options (providing also some benefit to another person at a particular social distance). At the behavioral level, testosterone reduced generosity compared to the placebo. At the neural level (n = 60), the temporoparietal junction (TPJ) encoded the other-regarding value of the generous option during generous choices, and this effect was attenuated by testosterone, suggesting that testosterone reduced the consideration of other's welfare as underpinned by TPJ activity. Moreover, TPJ activity more strongly reflected individual differences in generosity in the placebo than the testosterone group. Furthermore, testosterone weakened the relation between the other-regarding value of generous decisions and connectivity between the TPJ and a region extending from the insula into the striatum. Together, these findings suggest that a network encompassing both cortical and subcortical components underpins the effects of testosterone on social preferences.


Asunto(s)
Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/fisiología , Personalidad/efectos de los fármacos , Testosterona/farmacología , Mapeo Encefálico , Estudios de Casos y Controles , Corteza Cerebral/diagnóstico por imagen , Toma de Decisiones , Humanos , Imagen por Resonancia Magnética , Masculino , Conducta Social
19.
J Formos Med Assoc ; 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38514372

RESUMEN

BACKGROUND: Postoperative radiotherapy (PORT) and concurrent chemoradiation (CCRT) are indicated for patients with advanced oral cancer. However, the benefits for pT1-2N1 disease without adverse pathological features are controversial. METHODS: This retrospective study using the Taiwan Cancer Registry database included patients with pT1-2N1 oral cancer from January 1, 2011, to December 31, 2017. Overall survival was analyzed in patients receiving surgery alone, PORT, or CCRT. RESULTS: Among the 862 patients, the five-year overall survival rate in patients receiving surgery alone, PORT, and CCRT was 62.2%, 58.7%, and 71.1% (P = 0.03), respectively. CCRT was associated with longer survival than PORT (P = 0.008). Survival in patients with pT2 disease was significantly higher with CCRT than PORT (P = 0.001), but no difference was observed in pT1 disease. CONCLUSION: CCRT demonstrated a favorable impact on survival outcomes in patients diagnosed with pT2N1 oral cancer when compared to PORT. However, no significant survival benefits were observed for patients with pT1 disease.

20.
Sensors (Basel) ; 24(15)2024 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-39124093

RESUMEN

High-strength bolts play a crucial role in ultra-high-pressure equipment such as bridges and railway tracks. Effective monitoring of bolt conditions is of paramount importance for common fault repair and accident prevention. This paper aims to detect and classify bolt corrosion levels accurately. We design and implement a bolt corrosion classification system based on a Wireless Acoustic Emission Sensor Network (WASN). Initially, WASN nodes collect high-speed acoustic emission (AE) signals from bolts. Then, the ReliefF feature selection algorithm is applied to identify the optimal feature combination. Subsequently, the Extreme Learning Machine (ELM) model is utilized for bolt corrosion classification. Additionally, to achieve high prediction accuracy, an improved goose algorithm (GOOSE) is employed to ensure the most suitable parameter combination for the ELM model. Experimental measurements were conducted on five classes of bolt corrosion levels: 0%, 25%, 50%, 75%, and 100%. The classification accuracy obtained using the proposed method was at least 98.04%. Compared to state-of-the-art classification diagnostic models, our approach exhibits superior AE signal recognition performance and stronger generalization ability to adapt to variations in working conditions.

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