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Majorana zero modes (MZMs) are emergent zero-energy topological quasiparticles that are their own antiparticles1,2. Detected MZMs are spatially separated and electrically neutral, so producing hybridization between MZMs is extremely challenging in superconductors3,4. Here, we report the magnetic field response of vortex bound states in superconducting topological crystalline insulator SnTe (001) films. Several MZMs were predicted to coexist in a single vortex due to magnetic mirror symmetry. Using a scanning tunnelling microscope equipped with a three-axis vector magnet, we found that the zero-bias peak (ZBP) in a single vortex exhibits an apparent anisotropic response even though the magnetic field is weak. The ZBP can robustly extend a long distance of up to approximately 100 nm at the (001) surface when the magnetic field is parallel to the ( 1 1 ¯ 0 )-type mirror plane, otherwise it displays an asymmetric splitting. Our systematic simulations demonstrate that the anisotropic response cannot be reproduced with trivial ZBPs. Although the different MZMs cannot be directly distinguished due to the limited energy resolution in our experiments, our comparisons between experimental measurements and theoretical simulations strongly support the existence and hybridization of symmetry-protected multiple MZMs. Our work demonstrates a way to hybridize different MZMs by controlling the orientation of the magnetic field and expands the types of MZM available for tuning topological states.
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Vesicular transport relies on multimeric trafficking complexes to capture cargo and drive vesicle budding and fusion. Faithful assembly of the trafficking complexes is essential to their functions but remains largely unexplored. Assembly of AP2 adaptor, a heterotetrameric protein complex regulating clathrin-mediated endocytosis, is assisted by the chaperone AAGAB. Here, we found that AAGAB initiates AP2 assembly by stabilizing its α and σ2 subunits, but the AAGAB:α:σ2 complex cannot recruit additional AP2 subunits. We identified CCDC32 as another chaperone regulating AP2 assembly. CCDC32 recognizes the AAGAB:α:σ2 complex, and its binding leads to the formation of an α:σ2:CCDC32 ternary complex. The α:σ2:CCDC32 complex serves as a template that sequentially recruits the µ2 and ß2 subunits of AP2 to complete AP2 assembly, accompanied by CCDC32 release. The AP2-regulating function of CCDC32 is disrupted by a disease-causing mutation. These findings demonstrate that AP2 is assembled by a handover mechanism switching from AAGAB-based initiation complexes to CCDC32-based template complexes. A similar mechanism may govern the assembly of other trafficking complexes exhibiting the same configuration as AP2.
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Complejo 2 de Proteína Adaptadora , Chaperonas Moleculares , Complejo 2 de Proteína Adaptadora/metabolismo , Complejo 2 de Proteína Adaptadora/genética , Humanos , Chaperonas Moleculares/metabolismo , Chaperonas Moleculares/genética , Unión Proteica , Endocitosis/fisiología , Transporte de ProteínasRESUMEN
The analysis of tissues of origin of cell-free DNA (cfDNA) is of research and diagnostic interest. Many studies focused on bisulfite treatment or immunoprecipitation protocols to assess the tissues of origin of cfDNA. DNA loss often occurs during such processes. Fragmentomics of cfDNA molecules has uncovered a wealth of information related to tissues of origin of cfDNA. There is still much room for the development of tools for assessing contributions from various tissues into plasma using fragmentomic features. Hence, we developed an approach to analyze the relative contributions of DNA from different tissues into plasma, by identifying characteristic fragmentation patterns associated with selected histone modifications. We named this technique as FRAGmentomics-based Histone modification Analysis (FRAGHA). Deduced placenta-specific histone H3 lysine 27 acetylation (H3K27ac)-associated signal correlated well with the fetal DNA fraction in maternal plasma (Pearson's r = 0.96). The deduced liver-specific H3K27ac-associated signal correlated with the donor-derived DNA fraction in liver transplantation recipients (Pearson's r = 0.92) and was significantly increased in patients with hepatocellular carcinoma (HCC) (P < 0.01, Wilcoxon rank-sum test). Significant elevations of erythroblasts-specific and colon-specific H3K27ac-associated signals were observed in patients with ß-thalassemia major and colorectal cancer, respectively. Furthermore, using the fragmentation patterns from tissue-specific H3K27ac regions, a machine learning algorithm was developed to enhance HCC detection, with an area under the curve (AUC) of up to 0.97. Finally, genomic regions with H3K27ac or histone H3 lysine 4 trimethylation (H3K4me3) were found to exhibit different fragmentomic patterns of cfDNA. This study has shed light on the relationship between cfDNA fragmentomics and histone modifications, thus expanding the armamentarium of liquid biopsy.
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Ácidos Nucleicos Libres de Células , Fragmentación del ADN , Código de Histonas , Histonas , Nucleosomas , Humanos , Nucleosomas/metabolismo , Ácidos Nucleicos Libres de Células/sangre , Ácidos Nucleicos Libres de Células/genética , Histonas/metabolismo , Histonas/sangre , Femenino , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/genética , Carcinoma Hepatocelular/sangre , Carcinoma Hepatocelular/genética , Embarazo , Acetilación , Placenta/metabolismo , MasculinoRESUMEN
Assembly of protein complexes is facilitated by assembly chaperones. Alpha and gamma adaptin-binding protein (AAGAB) is a chaperone governing the assembly of the heterotetrameric adaptor complexes 1 and 2 (AP1 and AP2) involved in clathrin-mediated membrane trafficking. Here, we found that before AP1/2 binding, AAGAB exists as a homodimer. AAGAB dimerization is mediated by its C-terminal domain (CTD), which is critical for AAGAB stability and is missing in mutant proteins found in patients with the skin disease punctate palmoplantar keratoderma type 1 (PPKP1). We solved the crystal structure of the dimerization-mediating CTD, revealing an antiparallel dimer of bent helices. Interestingly, AAGAB uses the same CTD to recognize and stabilize the γ subunit in the AP1 complex and the α subunit in the AP2 complex, forming binary complexes containing only one copy of AAGAB. These findings demonstrate a dual role of CTD in stabilizing resting AAGAB and binding to substrates, providing a molecular explanation for disease-causing AAGAB mutations. The oligomerization state transition mechanism may also underlie the functions of other assembly chaperones.
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Proteínas Adaptadoras del Transporte Vesicular , Queratodermia Palmoplantar , Humanos , Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Proteínas Portadoras/genética , Queratodermia Palmoplantar/genética , Queratodermia Palmoplantar/metabolismo , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Clatrina/metabolismo , Complejo 2 de Proteína Adaptadora/genética , Complejo 2 de Proteína Adaptadora/metabolismoRESUMEN
The endoplasmic reticulum (ER)-plasma membrane (PM) contact sites (EPCSs) are structurally conserved in eukaryotes. The Arabidopsis ER-anchored synaptotagmin 1 (SYT1), enriched in EPCSs, plays a critical role in plant abiotic stress tolerance. It has become clear that SYT1 interacts with PM to mediate ER-PM connectivity. However, whether SYT1 performs additional functions at EPCSs remains unknown. Here, we report that SYT1 efficiently transfers phospholipids between membranes. The lipid transfer activity of SYT1 is highly dependent on phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2 ], a signal lipid accumulated at the PM under abiotic stress. Mechanically, while SYT1 transfers lipids fundamentally through the synaptotagmin-like mitochondrial-lipid-binding protein (SMP) domain, the efficient lipid transport requires the C2A domain-mediated membrane tethering. Interestingly, we observed that Ca2+ could stimulate SYT1-mediated lipid transport. In addition to PI(4,5)P2 , the Ca2+ activation requires the phosphatidylserine, another negatively charged lipid on the opposed membrane. Together, our studies identified Arabidopsis SYT1 as a lipid transfer protein at EPCSs and demonstrated that it takes conserved as well as divergent mechanisms with other extend-synaptotagmins. The critical role of lipid composition and Ca2+ reveals that SYT1-mediated lipid transport is highly regulated by signals in response to abiotic stresses.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Calcio/metabolismo , Membrana Celular/metabolismo , Fosfatidilinositoles/metabolismo , Sinaptotagmina I/metabolismoRESUMEN
The clinical implementation of pharmacogenetic biomarkers continues to grow as new genetic variants associated with drug outcomes are discovered and validated. The number of drug labels that contain pharmacogenetic information also continues to expand. Published, peer-reviewed clinical practice guidelines have also been developed to support the implementation of pharmacogenetic tests. Incorporating pharmacogenetic information into health care benefits patients as well as clinicians by improving drug safety and reducing empiricism in drug selection. Barriers to the implementation of pharmacogenetic testing remain. This review explores current pharmacogenetic implementation initiatives with a focus on the challenges of pharmacogenetic implementation and potential opportunities to overcome these challenges.
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Farmacogenética , Pruebas de Farmacogenómica , Atención a la Salud , HumanosRESUMEN
BACKGROUND: Biologic asthma therapies reduce exacerbations and long-term oral corticosteroids (LTOCS) use in randomized controlled trials (RCTs); however, there are limited data on outcomes among patients ineligible for RCTs. Hence, we investigated responsiveness to biologics in a real-world population of adults with severe asthma. METHODS: Adults in the International Severe Asthma Registry (ISAR) with ≥24 weeks of follow-up were grouped into those who did, or did not, initiate biologics (anti-IgE, anti-IL5/IL5R, anti-IL4/13). Treatment responses were examined across four domains: forced expiratory volume in 1 second (FEV1) increase by ≥100 mL, improved asthma control, annualized exacerbation rate (AER) reduction ≥50%, and any LTOCS dose reduction. Super-response criteria were: FEV1 increase by ≥500 mL, new well-controlled asthma, no exacerbations, and LTOCS cessation or tapering to ≤5 mg/day. RESULTS: 5.3% of ISAR patients met basic RCT inclusion criteria; 2116/8451 started biologics. Biologic initiators had worse baseline impairment than non-initiators, despite having similar biomarker levels. Half or more of initiators had treatment responses: 59% AER reduction, 54% FEV1 increase, 49% improved control, 49% reduced LTOCS, of which 32%, 19%, 30%, and 39%, respectively, were super-responses. Responses/super-responses were more frequent in biologic initiators than in non-initiators; nevertheless, ~40-50% of initiators did not meet response criteria. CONCLUSIONS: Most patients with severe asthma are ineligible for RCTs of biologic therapies. Biologics are initiated in patients who have worse baseline impairments than non-initiators despite similar biomarker levels. Although biologic initiators exhibited clinical responses and super-responses in all outcome domains, 40-50% did not meet the response criteria.
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Antiasmáticos , Asma , Productos Biológicos , Sistema de Registros , Índice de Severidad de la Enfermedad , Humanos , Asma/tratamiento farmacológico , Productos Biológicos/uso terapéutico , Masculino , Femenino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto , Antiasmáticos/uso terapéutico , Estudios de Cohortes , AncianoRESUMEN
OBJECTIVE: Radiotherapy is a crucial treatment modality for pelvic cancers, but uncertainties persist in defining the clinical target volume (CTV) for the inguinal lymphatic drainage region. Suboptimal CTV delineation may compromise treatment efficacy and result in subpar disease control. This study aimed to investigate and map the distribution of lymph node metastases (LNM) in the groin area to facilitate an improved and detailed CTV definition using 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT). METHODS: Inguinal LNM in patients with biopsy-proven pelvic malignancies were identified using 18F-FDG PET/CT scan. The longitudinally nearest axial plane was determined based on six typical bony landmarks, and the axial direction relative to the femoral artery of LNM was recorded. The distances from the LNM to the nearest edge of the femoral artery were measured on the axial plane. An optimal margin to cover 95% of LNM was estimated to develop contouring recommendations. RESULTS: In this study, 500 positive LNM were identified by 18F-FDG PET/CT among 185 patients with primary pelvic malignancies. Relative to the femoral artery, lymph nodes were distributed laterally (10:00-11:00, n = 35), anteriorly (12:00-1:00, n = 213), and medially (2:00-4: 00, n = 252). For CTV delineation, the recommended distances from the femoral artery on the SFH were lateral 19 mm, anterior 19 mm, and medial 25 mm; on the SGT were lateral 26 mm, anterior 20 mm, and medial 25 mm; on the SPS were lateral 28 mm, anterior 29 mm, and medial 26 mm; on the IPS were anterior 29 mm and medial 28 mm; on the IIT were anterior 27 mm and medial 27 mm; on the ILT were anterior 25 mm and medial 23 mm. Use interpolation to contour the area between six axial slices, including any radiographically suspicious LNM. CONCLUSIONS: Using 18F-FDG PET/CT, we investigated the distribution pattern of inguinal LNM and propose a more comprehensive guideline for inguinal CTV delineation.
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Fluorodesoxiglucosa F18 , Ganglios Linfáticos , Metástasis Linfática , Tomografía Computarizada por Tomografía de Emisión de Positrones , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Femenino , Masculino , Persona de Mediana Edad , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patología , Anciano , Adulto , Metástasis Linfática/diagnóstico por imagen , Anciano de 80 o más Años , Conducto Inguinal/diagnóstico por imagen , Conducto Inguinal/patología , Neoplasias Pélvicas/diagnóstico por imagen , Neoplasias Pélvicas/patología , Neoplasias Pélvicas/radioterapia , Radiofármacos , Ingle/diagnóstico por imagen , Ingle/patología , Adulto JovenRESUMEN
A 5-year-old female diagnosed with severe hemophilia B began experiencing frequent muscular and joint bleeds at 19 months old. Molecular studies, including Sanger sequencing, Giemsa banding, human androgen receptor (HUMARA) assay, array-based comparative genomic hybridization (aCGH), whole-exome sequencing (WES), and multiplex ligation-dependent probe amplification (MLPA), revealed a heterozygous factor IX (F9) intron 3 substitution (c.277+1G>T) inherited from her mother and a de novo heterozygous 441 kb deletion in the Xq28 region, which flanked intron 22 homologous regions 1 (int22h1) and 2 (int22h2). This rare genetic profile explains her severe phenotype and guides hereditary consultation for family planning.
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Hemofilia B , Inactivación del Cromosoma X , Humanos , Femenino , Preescolar , Hemofilia B/genética , Cromosomas Humanos X/genética , Factor IX/genética , Deleción Cromosómica , IntronesRESUMEN
OBJECTIVE: This study evaluates the feasibility and efficacy of implanting a leadless pacemaker at the right atrial appendage (RAA) in a preclinical minipig model, aiming to address the limitations of atrial pacing with current leadless devices like the Medtronic Micra, which is typically used for right ventricular implantation. METHODS: Four minipigs, each with a median body weight of 45.8 ± 10.0 kg, underwent placement of the Micra transcatheter pacing system (TPS) via the right femoral vein into the RAA apex. The pacing performance was assessed over 1-week (short-term) and 3-month (long-term) periods. OUTCOMES: The initial findings indicated successful implantation, with satisfactory intrinsic R-wave amplitudes and pacing threshold. In the following period, the sensitivity, threshold, and impedance were stable with time. Notably, upon explanation at 3 months, a deep myocardial penetration by the device was observed, necessitating a redesign for safe long-term use in a growing subject's heart. CONCLUSION: While initial results suggest that RAA apex placement of the Micra TPS is promising for potential inclusion in a dual-chamber pacing system, the issue of myocardial penetration highlights the need for device redesign to ensure safety and effectiveness in long-term applications.
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Apéndice Atrial , Diseño de Equipo , Marcapaso Artificial , Porcinos Enanos , Animales , Porcinos , Apéndice Atrial/cirugía , Estudios de Factibilidad , Estimulación Cardíaca Artificial/métodosRESUMEN
PURPOSE: Muscle radiodensity loss after surgery and adjuvant chemotherapy is associated with poor outcomes in ovarian cancer. Assessing muscle radiodensity is a real-world clinical challenge owing to the requirement for computed tomography (CT) with consistent protocols and labor-intensive processes. This study aimed to use interpretable machine learning (ML) to predict muscle radiodensity loss. METHODS: This study included 723 patients with ovarian cancer who underwent primary debulking surgery and platinum-based chemotherapy between 2010 and 2019 at two tertiary centers (579 in cohort 1 and 144 in cohort 2). Muscle radiodensity was assessed from pre- and post-treatment CT acquired with consistent protocols, and a decrease in radiodensity ≥ 5% was defined as loss. Six ML models were trained, and their performances were evaluated using the area under the curve (AUC) and F1-score. The SHapley Additive exPlanations (SHAP) method was applied to interpret the ML models. RESULTS: The CatBoost model achieved the highest AUC of 0.871 (95% confidence interval, 0.870-0.874) and F1-score of 0.688 (95% confidence interval, 0.685-0.691) among the models in the training set and outperformed in the external validation set, with an AUC of 0.839 and F1-score of 0.673. Albumin change, ascites, and residual disease were the most important features associated with a higher likelihood of muscle radiodensity loss. The SHAP force plot provided an individualized interpretation of model predictions. CONCLUSION: An interpretable ML model can assist clinicians in identifying ovarian cancer patients at risk of muscle radiodensity loss after treatment and understanding the contributors of muscle radiodensity loss.
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Aprendizaje Automático , Neoplasias Ováricas , Tomografía Computarizada por Rayos X , Humanos , Femenino , Neoplasias Ováricas/patología , Persona de Mediana Edad , Tomografía Computarizada por Rayos X/métodos , Anciano , Estudios Retrospectivos , Adulto , Quimioterapia Adyuvante/métodos , Quimioterapia Adyuvante/efectos adversos , Procedimientos Quirúrgicos de Citorreducción/métodosRESUMEN
Di(2-ethylhexyl) phthalate (DEHP) is a worldwide common plasticizer. Nevertheless, DEHP is easily leached out to the environment due to the lack of covalent bonds with plastic. High dose of DEHP exposure is often observed in hemodialysis patients because of the continual usage of plastic medical devices. Although the liver is the major organ that catabolizes DEHP, the impact of long-term DEHP exposure on the sensitivity of liver cancer to chemotherapy remains unclear. In this study, we established long-term DEHP-exposed hepatocellular carcinoma (HCC) cells and two NOD/SCID mice models to investigate the effects and the underlying mechanisms of long-term DEHP exposure on chemosensitivity of HCC. The results showed long-term DEHP exposure potentially increased epithelial-mesenchymal transition (EMT) in HCC cells. Next generation sequencing showed that long-term DEHP exposure increased cell adhesion/migratory related genes expression and blunted sorafenib treatment induced genes alterations. Long-term exposure to DEHP reduced the sensitivity of HCC cells to sorafenib-induced anti-migratory effect by enhancing the EMT transcription factors (slug, twist, and ZEB1) and mesenchymal protein (vimentin) expression. In NOD/SCID mice model, we showed that long-term DEHP-exposed HCC cells exhibited higher growth rate. Regarding the anti-HCC effects of sorafenib, subcutaneous HuH7 tumor grew slowly in sorafenib-treated mice. Nonetheless, the anti-tumor growth effect of sorafenib was not observed in long-term DEHP-exposed mice. Higher mesenchymal markers and proliferating cell nuclear antigen (PCNA) expression were found in sorafenib-treated long-term DEHP-exposed mice. In conclusion, long-term DEHP exposure promoted migratory activity in HCC cells and decreased sorafenib sensitivity in tumor-bearing mice.
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Carcinoma Hepatocelular , Dietilhexil Ftalato , Neoplasias Hepáticas , Ácidos Ftálicos , Humanos , Ratones , Animales , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Sorafenib/farmacología , Sorafenib/uso terapéutico , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Dietilhexil Ftalato/toxicidad , Ratones SCID , Ratones Endogámicos NOD , Resultado del TratamientoRESUMEN
The electrochemical CO2 reduction reaction (CO2RR) provides an alternative protocol to producing industrial chemicals with renewable electricity sources, and the highly selective, durable, and economic catalysts should expedite CO2RR applications. Here, we demonstrate a composite Cu-In2O3 catalyst in which a trace amount of In2O3 decorated on Cu surface greatly improves the selectivity and stability for CO2-to-CO reduction as compared to the counterparts (Cu or In2O3), realizing a CO faradaic efficiency (FECO) of 95% at -0.7 V (vs RHE) and no obvious degradation within 7 h. In situ X-ray absorption spectroscopy reveals that In2O3 undergoes the redox reaction and preserves the metallic state of Cu during the CO2RR process. Strong electronic interaction and coupling occur at the Cu/In2O3 interface which serves as the active site for selective CO2RR. Theoretical calculation confirms the roles of In2O3 in preventing oxidation and altering the electronic structure of Cu to assist COOH* formation and demote CO* adsorption at the Cu/In2O3 interface.
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To assess the effects of hydroxysafflor yellow A (HSYA) on ultraviolet A (UVA)-induced damage in HaCaT keratinocytes. HaCaT keratinocytes were UVA-irradiated, and the effects of HSYA on cell viability, reactive oxygen species (ROS) generation, lipid peroxidation, and messenger (m)RNA expression were measured. mRNA expressions of matrix metalloproteinase (MMP)-1, MMP-2, MMP-9, and cyclooxygenase (COX)-2 were determined by a real-time polymerase chain reaction (RT-PCR). UVA exposure led to a decrease in cell viability and an increase in ROS generation in HaCaT keratinocytes. HSYA effectively increased the viability of HaCaT keratinocytes after UVA exposure and protected them from UVA-induced oxidative stress. Moreover, HSYA inhibited expressions of MMP-1, MMP-2, MMP-9, and COX-2 by HaCaT keratinocytes with UVA-induced photodamage. Our results suggest that HSYA can act as a free radical scavenger when keratinocytes are photodamaged. HSYA has the potential to be a skin-protective ingredient against UVA-induced photodamage.
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Supervivencia Celular , Chalcona , Células HaCaT , Queratinocitos , Quinonas , Especies Reactivas de Oxígeno , Rayos Ultravioleta , Humanos , Quinonas/farmacología , Rayos Ultravioleta/efectos adversos , Queratinocitos/efectos de los fármacos , Queratinocitos/efectos de la radiación , Queratinocitos/metabolismo , Chalcona/farmacología , Chalcona/análogos & derivados , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Especies Reactivas de Oxígeno/metabolismo , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/efectos de la radiación , Ciclooxigenasa 2/metabolismo , Ciclooxigenasa 2/genética , Metaloproteinasa 9 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/genética , Peroxidación de Lípido/efectos de los fármacos , Línea Celular , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 2 de la Matriz/genéticaRESUMEN
PURPOSE: Children with Autism Spectrum Disorder (ASD) have motor, social communication, and behavioral challenges. During the pandemic, children lost access to face-to-face (F2F) services and had to revert to telehealth (TH) options. We compared the efficacy, fidelity, acceptability, and feasibility of a general motor (GM) intervention using an F2F or telehealth (TH) format. METHODS: Fifteen children with ASD participated in an 8-week program involving gross motor games to promote motor and social communication skills. Differences across TH and F2F formats for motor and socially directed verbalization as well as stakeholder feedback on formats were collected. RESULTS: Gross motor and socially directed verbalization did not differ between the F2F and TH subgroups, and parents and trainers were satisfied with either format. However, TH interventions were longer, had more technological challenges, and required more parental effort. CONCLUSIONS: The findings of this study support the use of TH as a comparable and viable substitute for F2F interactions for children with ASD.
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Trastorno del Espectro Autista , Telemedicina , Humanos , Trastorno del Espectro Autista/rehabilitación , Proyectos Piloto , Masculino , Niño , Femenino , Preescolar , COVID-19 , Destreza MotoraRESUMEN
α-Synuclein (α-Syn) is the major protein component of Lewy bodies, a key pathological feature of Parkinson's disease (PD). The manganese ion Mn2+ has been identified as an environmental risk factor of PD. However, it remains unclear how Mn2+ regulates α-Syn aggregation. Here, we discovered that Mn2+accelerates α-Syn amyloid aggregation through the regulation of protein phase separation. We found that Mn2+ not only promotes α-Syn liquid-to-solid phase transition but also directly induces soluble α-Syn monomers to form solid-like condensates. Interestingly, the lipid membrane is integrated into condensates during Mn2+-induced α-Syn phase transition; however, the preformed Mn2+/α-syn condensates can only recruit lipids to the surface of condensates. In addition, this phase transition can largely facilitate α-Syn amyloid aggregation. Although the Mn2+-induced condensates do not fuse, our results demonstrated that they could recruit soluble α-Syn monomers into the existing condensates. Furthermore, we observed that a manganese chelator reverses Mn2+-induced α-Syn aggregation during the phase transition stage. However, after maturation, α-Syn aggregation becomes irreversible. These findings demonstrate that Mn2+ facilitates α-Syn phase transition to accelerate the formation of α-Syn aggregates and provide new insights for targeting α-Syn phase separation in PD treatment.
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Amiloide , Amiloidosis , Manganeso , Enfermedad de Parkinson , alfa-Sinucleína , Amiloide/metabolismo , Proteínas Amiloidogénicas/metabolismo , Amiloidosis/metabolismo , Humanos , Cuerpos de Lewy/metabolismo , Manganeso/metabolismo , Enfermedad de Parkinson/metabolismo , Agregado de Proteínas , Agregación Patológica de Proteínas/metabolismo , alfa-Sinucleína/metabolismoRESUMEN
BACKGROUNDS: HLA-B*58:01 allele was strongly associated with allopurinol induced severe cutaneous adverse drug reaction (SCAR). However, HLA-B genotype is not sufficient to predict the occurrence of allopurinol-induced SCAR. OBJECTIVE: To discover DNA methylation markers for allopurinol-induced SCAR which may improve the prediction accuracy of genetic testing. STUDY DESIGN: The study was designed as a retrospective case-control clinical study in multicenter hospitals across Taiwan, Mainland China, Malaysia and Canada. 125 cases of allopurinol-induced SCAR patients and 139 cases of allopurinol tolerant controls were enrolled in this study during 2005 to 2021. RESULTS: The results of genome-wide DNA methylation assay of 62 patients revealed that ITGB2 showed strong discriminative ability of allopurinol-induced SCAR in both HLA-B*58:01 positive and negative patients with AUC value of 0.9364 (95% CI 0.8682-1.000). In validation study, significant hypermethylation of ITGB2 were further validated in allopurinol-induced SCAR patients compared to tolerant controls, especially in those without HLA-B*58:01(AUC value of 0.8814 (95% CI 0.7121-1.000)). Additionally, the methylation levels of 2 sites on ITGB2 were associated with SCAR phenotypes. Combination of HLA-B*58:01 genotyping and ITGB2 methylation status could improve the prediction accuracy of allopurinol-induced SCAR with the AUC value up to 0.9387 (95% CI 0.9089-0.9684), while the AUC value of HLA-B*58:01 genotyping alone was 0.8557 (95% CI 0.8030-0.9083). CONCLUSIONS: Our study uncovers differentially methylated genes between allopurinol-induced SCAR patients and tolerant controls with positive or negative HLA-B*58:01 allele and provides the novel epigenetic marker that improves the prediction accuracy of genetic testing for prevention of allopurinol-induced SCAR.
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Hipersensibilidad a las Drogas , Síndrome de Stevens-Johnson , Humanos , Alopurinol/efectos adversos , Estudios Retrospectivos , Metilación de ADN , Hipersensibilidad a las Drogas/epidemiología , Antígenos HLA-B/genética , Síndrome de Stevens-Johnson/tratamiento farmacológico , Síndrome de Stevens-Johnson/genéticaRESUMEN
Multimeric cargo adaptors such as AP2 play central roles in intracellular membrane trafficking. We recently discovered that the assembly of the AP2 adaptor complex, a key player in clathrin-mediated endocytosis, is a highly organized process controlled by alpha- and gamma-adaptin-binding protein (AAGAB, also known as p34). In this study, we demonstrate that besides AP2, AAGAB also regulates the assembly of AP1, a cargo adaptor involved in clathrin-mediated transport between the trans-Golgi network and the endosome. However, AAGAB is not involved in the formation of other adaptor complexes, including AP3. AAGAB promotes AP1 assembly by binding and stabilizing the γ and σ subunits of AP1, and its mutation abolishes AP1 assembly and disrupts AP1-mediated cargo trafficking. Comparative proteomic analyses indicate that AAGAB mutation massively alters surface protein homeostasis, and its loss-of-function phenotypes reflect the synergistic effects of AP1 and AP2 deficiency. Taken together, these findings establish AAGAB as an assembly chaperone for both AP1 and AP2 adaptors and pave the way for understanding the pathogenesis of AAGAB-linked diseases.
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Complejo 2 de Proteína Adaptadora , Proteínas Adaptadoras del Transporte Vesicular , Complejo 1 de Proteína Adaptadora/genética , Complejo 2 de Proteína Adaptadora/genética , Proteínas Adaptadoras del Transporte Vesicular/genética , Clatrina/genética , Endocitosis , ProteómicaRESUMEN
Two new compounds, aphegiractin A1/A2 (1a/1b), and seven known compounds were isolated by phytochemical work on EtOAc-soluble ingredients extracted from stem and root barks of Daphne giraldii. Their structures were established based on extensive spectroscopic methods, including HRESIMS, CD experiments, 1D and 2D NMR. All compounds were evaluated for their antioxidant activity to DPPH, ABTS radical scavenging activity and inhibitory activity on tyrosinase. Of these compounds, compound 3 exhibited significant antioxidant activities.
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Daphne , Daphne/química , Antioxidantes/farmacología , Estructura MolecularRESUMEN
Pulmonary fibrosis (PF) is a chronic lung disorder characterized by the presence of scarred and thickened lung tissues. Although the Food and Drug Administration approved two antifibrotic drugs, pirfenidone, and nintedanib, that are currently utilized for treating idiopathic PF (IPF), the clinical therapeutic efficacy remains unsatisfactory. It is crucial to develop new drugs or treatment schemes that combine pirfenidone or nintedanib to achieve more effective outcomes for PF patients. Understanding the complex mechanisms underlying PF could potentially facilitate drug discovery. Previous studies have found that the activation of inflammasomes, including nucleotide-binding and oligomerization domain (NOD)-like receptor protein (NLRP)1, NLRP3, NOD-like receptor C4, and absent in melanoma (AIM)2, contributes to lung inflammation and fibrosis. This article aims to summarize the cellular and molecular regulatory cues that contribute to PF with a particular emphasis on the role of AIM2 inflammasome in mediating pathophysiologic events during PF development. The insights gained from this research may pave the way for the development of more effective strategies for the prevention and treatment of PF.