RESUMEN
mRNA vaccines have been revolutionizing disease prevention and treatment. However, their further application is hindered by inflammatory side effects, primarily caused by delivery systems such as lipid nanoparticles (LNPs). In response to this issue, we prepared cationic lipids (mLPs) derived from mildronate, a small-molecule drug, and subsequently developed the LNP (mLNP-69) comprising a low dose of mLP. Compared with the LNP (sLNP) based on SM-102, a commercially available ionizable lipid, mLNP-69 ensures effective mRNA delivery while significantly reducing local inflammation. In preclinical prophylactic and therapeutic B16-OVA melanoma models, mLNP-69 demonstrated successful mRNA cancer vaccine delivery in vivo, effectively preventing tumor occurrence or impeding tumor progression. The results suggest that the cationic lipids derived from mildronate, which exhibit efficient delivery capabilities and minimal inflammatory side effects, hold great promise for clinical application.
RESUMEN
A sensitive, rapid, and simple HPLC-MS/MS method was first developed and fully validated to determine the icaritin (ICT) and its novel 3-methylcarbamate prodrug (3N) simultaneously in rat plasma. Analytes were extracted from rat plasma using a liquid-liquid extraction (LLE) method. Chromatographic separation was performed on ACE Excel 2 C18-Amide column. Quantitation of analytes was conducted on an LCMS-8060 triple-quadrupole tandem mass spectrometer. The quantitation mode was the multiple reaction monitoring via positive electrospray ionization. The calibration curve was linear over the concentration range of 1 to 200 ng/ml for ICT with a correlation coefficient of r = 0.9950 and 1 to 400 ng/ml for 3N with a correlation coefficient of r = 0.9956. The intra-precision RSDs were ≤12% for ICT and 3N. The inter-day precision RSDs were ≤10% for ICT and 3N. The accuracy RE was between -2.6% and 7.8% for ICT and 3N. The average ICT, 3N and IS recoveries were 87.9%, 83.6%, and 84.3%. The plasma matrix of ICT and 3N complied with the guidelines. ICT and 3N were stable in rat plasma under various tested conditions. This work has been successfully applied to studying the pharmacokinetics of ICT and 3N.
RESUMEN
Existing strategies use bifunctional chimaeras to mediate extracellular protein degradation. However, these strategies rely on specific lysosome-trafficking receptors to facilitate lysosomal delivery, which may raise resistance concerns due to intrinsic cell-to-cell variation in receptor expression and mutations or downregulation of the receptors. Another challenge is establishing a universal platform applicable in multiple scenarios. Here, we develop MONOTAB (MOdified NanOparticle with TArgeting Binders), a plug-and-play monofunctional degradation platform that can drag extracellular targets into lysosomes for degradation. MONOTAB harnesses the inherent lysosome-targeting ability of certain nanoparticles to obviate specific receptor dependency and the hook effect. To achieve high modularity and programmable target specificity, we utilize the streptavidin-biotin interaction to immobilize antibodies or other targeting molecules on nanoparticles, through an antibody mounting approach or by direct binding. Our study reveals that MONOTAB can induce efficient degradation of diverse therapeutic targets, including membrane proteins, secreted proteins, and even extracellular vesicles.
Asunto(s)
Vesículas Extracelulares , Lisosomas , Nanopartículas , Proteolisis , Vesículas Extracelulares/metabolismo , Humanos , Lisosomas/metabolismo , Nanopartículas/química , Nanopartículas/metabolismo , Estreptavidina/metabolismo , Estreptavidina/química , Animales , Biotina/metabolismo , Biotina/química , Células HEK293RESUMEN
Introduction: Yeast peptides have garnered attention as valuable nutritional modifiers due to their potential health benefits. However, the precise mechanisms underlying their effects remain elusive. This study aims to explore the potential of yeast peptides, when added to diets, to mitigate lipopolysaccharide (LPS)-induced intestinal damage and microbiota alterations in rabbits. Methods: A total of 160 35-day-old Hyla line rabbits (0.96 ± 0.06 kg) were randomly assigned to 4 groups. These groups constituted a 2 × 2 factorial arrangement: basal diet (CON), 100 mg/kg yeast peptide diet (YP), LPS challenge + basal diet (LPS), LPS challenge +100 mg/kg yeast peptide diet (L-YP). The experiment spanned 35 days, encompassing a 7-day pre-feeding period and a 28-day formal trial. Results: The results indicated that yeast peptides mitigated the intestinal barrier damage induced by LPS, as evidenced by a significant reduction in serum Diamine oxidase and D-lactic acid levels in rabbits in the L-YP group compared to the LPS group (p < 0.05). Furthermore, in the jejunum, the L-YP group exhibited a significantly higher villus height compared to the LPS group (p < 0.05). In comparison to the LPS group, the L-YP rabbits significantly upregulated the expression of Claudin-1, Occludin-1 and ZO-1 in the jejunum (p < 0.05). Compared with the CON group, the YP group significantly reduced the levels of rabbit jejunal inflammatory cytokines (TNF-α, IL-1ß and IL-6) and decreased the relative mRNA expression of jejunal signaling pathway-associated inflammatory factors such as TLR4, MyD88, NF-κB and IL-1ß (p < 0.05). Additionally, notable changes in the hindgut also included the concentration of short-chain fatty acids (SCFA) of the YP group was significantly higher than that of the CON group (p < 0.05). 16S RNA sequencing revealed a substantial impact of yeast peptides on the composition of the cecal microbiota. Correlation analyses indicated potential associations of specific gut microbiota with jejunal inflammatory factors, tight junction proteins, and SCFA. Conclusion: In conclusion, yeast peptides have shown promise in mitigating LPS-induced intestinal barrier damage in rabbits through their anti-inflammatory effects, modulation of the gut microbiota, and maintenance of intestinal tight junctions.
RESUMEN
Cycloicaritin (CICT), a bioactive flavonoid derived from the genus Epimedium, exhibits a variety of beneficial biological activities, including promising anticancer effects. However, its poor oral bioavailability is attributed to its extremely low aqueous solubility and rapid elimination via phase II conjugative metabolism. To overcome these limitations, we designed and synthesized a series of carbamate-bridged prodrugs, protecting the hydroxyl group at the 3-position of cycloicaritin by binding with the N-terminus of a natural amino acid. The optimal prodrug 4b demonstrated a significant increase in aqueous solubility as compared to CICT, as well as improved stability in phase II metabolism, while allowing for a rapid release of CICT in the blood upon gastrointestinal absorption. The prodrug 4b also facilitated oral absorption through organic anion-transporting polypeptide 2B1-mediated transport and exhibited moderate cytotoxicity. Importantly, the prodrug enhanced the oral bioavailability of CICT and displayed dose-dependent antitumor activity with superior safety. In summary, the prodrug 4b is a novel potential antitumor drug candidate, and the carbamate-bridged amino acid prodrug approach is a promising strategy for the oral delivery of CICT.
Asunto(s)
Aminoácidos , Antineoplásicos , Carbamatos , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Profármacos , Solubilidad , Profármacos/síntesis química , Profármacos/química , Profármacos/farmacología , Humanos , Carbamatos/química , Carbamatos/farmacología , Carbamatos/síntesis química , Carbamatos/farmacocinética , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Animales , Relación Estructura-Actividad , Aminoácidos/química , Aminoácidos/farmacología , Aminoácidos/síntesis química , Estructura Molecular , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ratones , Agua/química , Línea Celular Tumoral , Flavonoides/química , Flavonoides/farmacología , Flavonoides/síntesis química , Flavonoides/farmacocinética , MasculinoRESUMEN
Repositionable self-expanding valves allow for repositioning during deployment to achieve optimal valve placement. However, the risk of brain injury associated with repositioning, as detected by diffusion-weighted magnetic resonance imaging (DW-MRI), is unknown. Consecutive patients undergoing transcatheter aortic valve replacement (TAVR) with repositionable self-expanding valves and receiving DW-MRI before and within 7 days post-TAVR procedure were included. The primary outcomes were incidence, number, total volume, and volume per lesion of the cerebral ischemic lesion in DW-MRI after TAVR. Univariate and multivariate logistic regression assessed the association between repositioning and bigger total lesion volume (> 1 cm3 or > 0.5 cm3). Negative binomial regressions were performed to explore the association between repositioning and number of lesions. A propensity score matching was performed to adjust the potential confounders. Moreover, inverse probability of treatment weighted regression model with nonstabilized weights was used as sensitivity analysis. Among 243 included patients, repositioning was performed in 116 (47.7%) patients. The incidence of overt stroke (1.7% vs. 1.6%, p = 0.927) and silent stroke (86.2% vs. 85.8%, p = 0.932) were comparable between two groups. However, the number of new lesions (5.0 [2.0-9.0] vs. 3.0 [2.0-6.0], p = 0.048), and total lesion volume (275.0 [90.0-947.5] mm3 vs. 180.0 [50.0-440.0] mm3, p = 0.022) were significantly higher in the repositioned group. Moreover, the proportion of patients with lesion size greater than 0.5 cm3 was higher in the repositioned group (37.9% vs. 22.0%, p = 0.007). The similar results were observed after propensity score matching. In both multivariate regression model and sensitivity analysis, the repositioning was the independent predictor of number of lesions and bigger total lesion volume after TAVR. The utilization of the repositioning feature may increase the number and volume of silent brain infarcts in DW-MRI in patients who underwent TAVR. (Transcatheter Aortic Valve Replacement Single Center Registry in Chinese Population [TORCH]; NCT02803294).
Asunto(s)
Lesiones Encefálicas , Reemplazo de la Válvula Aórtica Transcatéter , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Válvula Aórtica/cirugía , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/patología , Estenosis de la Válvula Aórtica/cirugía , Lesiones Encefálicas/etiología , Lesiones Encefálicas/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética , Prótesis Valvulares Cardíacas/efectos adversos , Incidencia , Factores de Riesgo , Accidente Cerebrovascular/etiología , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Reemplazo de la Válvula Aórtica Transcatéter/métodosRESUMEN
BACKGROUND: There are limited data available on the development of arrhythmias in patients at risk of high-degree atrioventricular block (HAVB) or complete heart block (CHB) following transcatheter aortic valve replacement (TAVR). OBJECTIVE: This study aimed to explore the incidence and evolution of arrhythmias by monitoring patients at risk of HAVB or CHB after TAVR using smartwatches. METHODS: We analyzed 188 consecutive patients in the prospective SMART TAVR (smartwatch-facilitated early discharge in patients undergoing TAVR) trial. Patients were divided into 2 groups according to the risk of HAVB or CHB. Patients were required to trigger a single-lead electrocardiogram (ECG) recording and send it to the Heart Health App via their smartphone. Physicians in the central ECG core lab would then analyze the ECG. The incidence and timing of arrhythmias and pacemaker implantation within a 30-day follow-up were compared. All arrhythmic events were adjudicated in a central ECG core lab. RESULTS: The mean age of the patients was 73.1 (SD 7.3) years, of whom 105 (55.9%) were men. The mean discharge day after TAVR was 2.0 (SD 1.8) days. There were no statistically significant changes in the evolution of atrial fibrillation or atrial flutter, Mobitz I, Mobitz II, and third-degree atrial ventricular block over time in the first month after TAVR. The incidence of the left bundle branch block (LBBB) increased in the first week and decreased in the subsequent 3 weeks significantly (P<.001). Patients at higher risk of HAVB or CHB received more pacemaker implantation after discharge (n=8, 9.6% vs n=2, 1.9%; P=.04). The incidence of LBBB was higher in the group with higher HAVB or CHB risk (n=47, 56.6% vs n=34, 32.4%; P=.001). The independent predictors for pacemaker implantation were age, baseline atrial fibrillation, baseline right bundle branch block, Mobitz II, and third-degree atrioventricular block detected by the smartwatch. CONCLUSIONS: Except for LBBB, no change in arrhythmias was observed over time in the first month after TAVR. A higher incidence of pacemaker implantation after discharge was observed in patients at risk of HAVB or CHB. However, Mobitz II and third-degree atrioventricular block detected by the smartwatch during follow-ups were more valuable indicators to predict pacemaker implantation after discharge from the index TAVR. TRIAL REGISTRATION: ClinicalTrials.gov NCT04454177; https://clinicaltrials.gov/study/NCT04454177.
Asunto(s)
Arritmias Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Masculino , Femenino , Anciano , Arritmias Cardíacas/etiología , Arritmias Cardíacas/fisiopatología , Estudios Prospectivos , Anciano de 80 o más Años , Electrocardiografía , Bloqueo Atrioventricular/etiología , Bloqueo Atrioventricular/terapiaRESUMEN
Purpose To introduce the cranial-dorsal-hip angle (â CDH) as a novel quantitative tool for assessing fetal position in the first trimester and to validate its feasibility for future AI applications. Materials and Methods 2520 first-trimester fetal NT exams with 2582 CRL images (January-August 2022) were analyzed at a tertiary hospital as the pilot group. Additionally, 1418 cases with 1450 fetal CRL images (September-December 2022) were examined for validation. Three expert sonographers defined a standard for fetal positions. â CDH measurements, conducted by two ultrasound technicians, were validated for consistency using Bland-Altman plots and the intra-class correlation coefficient (ICC). This method allowed for categorizing fetal positions as hyperflexion, neutral, and hyperextension based on â CDH. Comparative accuracy was assessed against Ioannou, Wanyonyi, and Roux methods using the weighted Kappa coefficient (k value). Results The pilot group comprised 2186 fetal CRL images, and the validation group included 1193 images. Measurement consistency was high (ICCs of 0.993; P<0.001). The established 95% reference range for â CDH in the neutral fetal position was 118.3° to 137.8°. The â CDH method demonstrated superior accuracy over the Ioannou, Wanyonyi, and Roux methods in both groups, with accuracy rates of 94.5% (k values: 0.874, 95%CI: 0.852-0.896) in the pilot group, and 92.6% (k values: 0.838, 95%CI: 0.806-0.871) in the validation group. Conclusion The â CDH method has been validated as a highly reproducible and accurate technique for first-trimester fetal position assessment. This sets the stage for its potential future integration into intelligent assessment models.
RESUMEN
BACKGROUND: There has not been a consensus on the prothesis sizing strategy in type 0 bicuspid aortic stenosis (AS) patients undergoing transcatheter aortic valve replacement (TAVR). Modifications to standard annular sizing strategies might be required due to the distinct anatomical characteristics. We have devised a downsizing strategy for TAVR using a self-expanding valve specifically for patients with type 0 bicuspid AS. The primary aim of this study is to compare the safety and efficacy of downsizing strategy with the Standard Annulus Sizing Strategy in TAVR for patients with type 0 bicuspid AS. TRIAL DESIGN: It is a prospective, multi-center, superiority, single-blinded, randomized controlled trial comparing the Down Sizing and Standard Annulus Sizing Strategy in patients with type 0 bicuspid aortic stenosis undergoing transcatheter aortic valve replacement. Eligible participants will include patients with severe type 0 bicuspid AS, as defined by criteria such as mean gradient across aortic valve ≥40 mmHg, peak aortic jet velocity ≥4.0 m/s, aortic valve area (AVA) ≤1.0 cm², or AVA index ≤0.6 cm2/m2. These patients will be randomly assigned, in a 1:1 ratio, to either the Down Sizing Strategy group or the Standard Sizing Strategy group. In the Down Sizing Strategy group, a valve one size smaller will be implanted if the "waist sign" manifests along with less than mild regurgitation during balloon pre-dilatation. The primary end point of the study is a composite of VARC-3 defined device success, absence of both permanent pacemaker implantation due to high-degree atrioventricular block and new-onset complete left bundle branch block. CONCLUSION: This study will compare the safety and efficacy of Down Sizing Strategy with the Standard Annulus Sizing Strategy and provide valuable insights into the optimal approach for sizing in TAVR patients with type 0 bicuspid AS. We hypothesize that the Down Sizing Strategy will demonstrate superiority when compared to the Standard Annulus Sizing Strategy. (Down Sizing Strategy (HANGZHOU Solution) vs Standard Sizing Strategy TAVR in Bicuspid Aortic Stenosis (Type 0) (TAILOR-TAVR), NCT05511792).
Asunto(s)
Estenosis de la Válvula Aórtica , Enfermedad de la Válvula Aórtica Bicúspide , Prótesis Valvulares Cardíacas , Diseño de Prótesis , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Estenosis de la Válvula Aórtica/cirugía , Enfermedad de la Válvula Aórtica Bicúspide/cirugía , Enfermedad de la Válvula Aórtica Bicúspide/complicaciones , Estudios Prospectivos , Método Simple Ciego , Válvula Aórtica/cirugía , Válvula Aórtica/anomalías , Válvula Aórtica/diagnóstico por imagen , Masculino , FemeninoRESUMEN
OBJECTIVE: To observe prosthetic-associated subclinical thrombotic events (PASTE) after transcatheter aortic valve implantation (TAVI) by cardiac CTA, and assess their impact on long-term patient outcomes. MATERIALS: We prospectively and consecutively enrolled 188 patients with severe aortic stenosis treated with TAVI from February 2014 to April 2017. At 5 years, 61 of 141 survived patients who had completed annual follow-up CTA (≥ 5 years) were included. We analyzed PASTE by CTA, including hypoattenuated leaflet thickening (HALT), sinus filling defect (SFD), and prosthesis filling defect (PFD). The primary outcome was a major adverse cardiovascular composite outcome (MACCO) of stroke, cardiac re-hospitalization, and bioprosthetic valve dysfunction (BVD); the secondary outcomes were bioprosthetic hemodynamics deterioration (PGmean) and cardiac dysfunction (LVEF). RESULTS: During a median follow-up time of 5.25 years, long-term incidence of HALT, SFD, and PFD were 54.1%, 37.7%, and 73.8%, respectively. In the primary outcome, SFD and early SFD were associated with the MACCO (SFD: p = 0.005; early SFD: p = 0.018), and SFD was a predictor of MACCO (HR: 2.870; 95% CI: 1.010 to 8.154, p = 0.048). In the secondary outcomes, HALT was associated with increased PGmean (p = 0.031), while persistent HALT was correlated with ΔPGmean (ß = 0.38, p = 0.035). SFD was negatively correlated with ΔLVEF (ß = -0.39, p = 0.041), and early SFD was negatively correlated with LVEF and ΔLVEF (LVEF: r = -0.50, p = 0.041; ΔLVEF: r = -0.53, p = 0.030). CONCLUSIONS: PASTE were associated with adverse long-term outcomes, bioprosthetic hemodynamics deterioration, and cardiac dysfunction. In particular, SFD was a predictor of MACCO and may be a potential target for anticoagulation after TAVI (NCT02803294). REGISTRATION: URL: https://www. CLINICALTRIALS: gov ; Unique identifier: NCT02803294. CRITICAL RELEVANCE STATEMENT: PASTE, especially SFD, after TAVI based on cardiac CTA findings impacts the long-term outcomes of patients which is a predictor of long-term major adverse outcomes in patients and may be a potential target for anticoagulation after TAVI. KEY POINTS: Transcatheter aortic valve implantation is being used more often; associated subclinical thromboses have not been thoroughly evaluated. Prosthetic-associated subclinical thrombotic events were associated with adverse outcomes, bioprosthetic hemodynamics deterioration, and cardiac dysfunction. Studies should be directed at these topics to determine if they should be intervened upon.
RESUMEN
Long-term observation of subcellular dynamics in living organisms is limited by background fluorescence originating from tissue scattering or dense labeling. Existing confocal approaches face an inevitable tradeoff among parallelization, resolution and phototoxicity. Here we present confocal scanning light-field microscopy (csLFM), which integrates axially elongated line-confocal illumination with the rolling shutter in scanning light-field microscopy (sLFM). csLFM enables high-fidelity, high-speed, three-dimensional (3D) imaging at near-diffraction-limit resolution with both optical sectioning and low phototoxicity. By simultaneous 3D excitation and detection, the excitation intensity can be reduced below 1 mW mm-2, with 15-fold higher signal-to-background ratio over sLFM. We imaged subcellular dynamics over 25,000 timeframes in optically challenging environments in different species, such as migrasome delivery in mouse spleen, retractosome generation in mouse liver and 3D voltage imaging in Drosophila. Moreover, csLFM facilitates high-fidelity, large-scale neural recording with reduced crosstalk, leading to high orientation selectivity to visual stimuli, similar to two-photon microscopy, which aids understanding of neural coding mechanisms.
RESUMEN
PURPOSE: Combined modality treatment with chemotherapy followed by consolidation radiation therapy (RT) provides excellent outcomes for patients with early-stage Hodgkin lymphoma. The international standard of care for consolidation RT, involved-site/involved-node radiation therapy (ISRT/INRT), has never been evaluated in a randomized phase 3 trial against the former standard involved-field radiation therapy (IFRT). METHODS AND MATERIALS: In the multicenter phase 3 GHSG (German Hodgkin Study Group) HD17 trial, patients with early-stage unfavorable Hodgkin lymphoma were randomized between the standard Combined modality treatment group and a positron-emission tomography (PET)-guided group. In the standard group, patients received 2 cycles of escalated bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (eBEACOPP) and 2 cycles of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) followed by 30 Gy IFRT. In the experimental group, patients received no further therapy if postchemotherapy PET was negative and 30 Gy GHSG INRT, comparable to and therefore termed here ISRT, if PET was positive. Here, we analyze the interim PET-positive patients in a post hoc analysis, and therefore the randomized comparison of IFRT versus INRT/ISRT. RESULTS: A total of 1100 patients were randomized, of which 311 had a positive PET after chemotherapy. Kaplan-Meier estimates of 4-year progression-free survival were 96.8% (95% CI, 91.6%-98.8%) in the IFRT group and 95.4% (95% CI, 89.9%-97.9%; HR, 1.40; 95% CI, 0.44-4.42) in the ISRT group. The pattern of recurrence analyses indicated that none of the cases of disease progression or recurrence in the ISRT group would have been prevented by the use of IFRT. Acute grade 3/4 toxicities occurred in 8.5% of IFRT patients and 2.6% of ISRT patients (P = .03). CONCLUSIONS: For the first time, consolidation INRT/ISRT was randomly compared with IFRT in a phase 3 trial. Regarding progression-free survival, no advantage of IFRT could be demonstrated. In summary, our data confirm the status of INRT/ISRT as the current standard of care.
RESUMEN
Tuberous Sclerosis Complex (TSC) is a severe developmental disorder with various clinical effects, primarily caused by TSC2 gene mutations, often involving loss of function(Henske,et al., 2016).To explore role of TSC2 in human heart development, we successfully developed a TSC2 knockout (TSC2-/-) human embryonic stem cells (hESCs) line using CRISPR/Cas9 gene editing. This TSC2-/- hESC line maintained a normal karyotype, expressed pluripotency markers strongly, and could differentiate into all three germ layers in vivo. This cell line will be a valuable tool for future research on the role of TSC2 in heart development.
Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Células Madre Embrionarias Humanas , Proteína 2 del Complejo de la Esclerosis Tuberosa , Humanos , Proteína 2 del Complejo de la Esclerosis Tuberosa/genética , Proteína 2 del Complejo de la Esclerosis Tuberosa/metabolismo , Células Madre Embrionarias Humanas/metabolismo , Células Madre Embrionarias Humanas/citología , Línea Celular , Técnicas de Inactivación de Genes , Diferenciación CelularRESUMEN
An imidazolyl hydrogen-bonded organic framework (HOF-T) with outstanding thermal and water stability was constructed by C-Hâ¯N hydrogen bonding and C-Hâ¯π interactions. UO22+ can be selectively captured by the imidazole group of HOF-T and rapidly reduced to UO2 under visible light irradiation, realizing exceptional uranium removal with high capacity and fast kinetics.
RESUMEN
Fusion pore opening is a transient intermediate state of synaptic vesicle exocytosis, which is highly dynamic and precisely regulated by the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex and synaptotagmin-1 (Syt1). Yet, the regulatory mechanism is not fully understood. In this work, using single-channel membrane fusion electrophysiology, we determined that SNAREpins are important for driving fusion pore opening and dilation but incapable of regulating the dynamics. When Syt1 was added, the closing frequency of fusion pores significantly increased, while the radius of fusion pores mildly decreased. In response to Ca2+, SNARE/Syt1 greatly increased the radius of fusion pores and reduced their closing frequency. Moreover, the residue F349 in the C2B domain of Syt1, which mediates Syt1 oligomerization, was required for clamping fusion pore opening in the absence of Ca2+, probably by extending the distance between the two membranes. Finally, in Ca2+-triggered fusion, the primary interface between SNARE and Syt1 plays a critical role in stabilizing and dilating the fusion pore, while the polybasic region of Syt1 C2B domain has a mild effect on increasing the radius of the fusion pore. In summary, our results suggest that Syt1, SNARE, and the anionic membrane synergically orchestrate the dynamics of fusion pore opening in synaptic vesicle exocytosis.
RESUMEN
African swine fever (ASF), caused by the ASF virus (ASFV), is a hemorrhagic and fatal viral disease that affects Eurasian wild boars and domestic pigs, posing a substantial threat to the global pig breeding industry. ASFV, a double-stranded DNA virus, possesses a large genome containing up to 160 open reading frames, most of which exhibit unknown functions. The B125R gene of ASFV, located at the 105595-105972 bp site in the ASFV-SY18 genome, remains unexplored. In this study, we discovered that B125R deletion did not affect recombinant virus rescue, nor did it hinder viral replication during the intermediate growth phase. Although the virulence of the recombinant strain harboring this deletion was attenuated, intramuscular inoculation of the recombinant virus in pigs at doses of 102 or 104 TCID50 resulted in mortality. Moreover, sequencing analysis of six recombinant strains obtained from three independent experiments consistently revealed an adenine insertion at the 47367-47375 bp site in the A104R gene due to the B125R deletion, leading to premature termination of this gene. Intriguingly, this insertion did not influence the transcription of the A104R gene between the recombinant and parental strains. Consequently, we postulate that the deletion of the B125R gene in ASFV-SY18 or other genotype II strains may marginally attenuate virulence in domestic pigs.
Asunto(s)
Virus de la Fiebre Porcina Africana , Fiebre Porcina Africana , Porcinos , Animales , Virus de la Fiebre Porcina Africana/genética , Sus scrofa , Virulencia , Mutación del Sistema de Lectura , Eliminación de GenRESUMEN
Introduction: African swine fever (ASF) is an infectious disease that causes considerable economic losses in pig farming. The agent of this disease, African swine fever virus (ASFV), is a double-stranded DNA virus with a capsid membrane and a genome that is 170-194 kb in length encoding over 150 proteins. In recent years, several live attenuated strains of ASFV have been studied as vaccine candidates, including the SY18ΔL7-11. This strain features deletion of L7L, L8L, L9R, L10L and L11L genes and was found to exhibit significantly reduced pathogenicity in pigs, suggesting that these five genes play key roles in virulence. Methods: Here, we constructed and evaluated the virulence of ASFV mutations with SY18ΔL7, SY18ΔL8, SY18ΔL9, SY18ΔL10, and SY18ΔL11L. Results: Our findings did not reveal any significant differences in replication efficiency between the single-gene deletion strains and the parental strains. Pigs inoculated with SY18ΔL8L, SY18ΔL9R and SY18ΔL10L exhibited clinical signs similar to those inoculated with the parental strains. Survival rate of pigs inoculated with 103.0TCID50 of SY18ΔL7L was 25%, while all pigs inoculated with 103.0TCID50 of SY18ΔL11L survived, and 50% inoculated with 106.0TCID50 SY18ΔL11L survived. Discussion: The results indicate that L8L, L9R and L10L do not affect ASFV SY18 virulence, while the L7L and L11L are associated with virulence.
RESUMEN
BACKGROUND: Aberrant circular RNA (circRNA) acts as an oncogene or suppressor during neoplasm initiation and development. However, the functions of most circRNAs in osteosarcoma (OS) remain unclear. OBJECTIVES: We aimed to investigate the expression, molecular functions and mechanisms underlying circRNAs in OS. MATERIAL AND METHODS: Network interaction, pathway enrichment and regression analyses were performed to determine differentially expressed (DE) circRNAs, microRNAs (miRNAs) and messenger RNAs (mRNAs). We constructed competitive endogenous RcodeNA (ceRNA) networks and integrated patient clinical data to analyze the relationship between the networks and prognosis. The circRNA, miRNA and mRNA data were retrieved from Gene Expression Omnibus (GEO) microarray datasets. A circRNA-miRNA-mRNA interaction network was established and visualized using miRNet. Protein interactions were investigated using STRING and Cytoscape, and hub genes were identified using the MCODE plug-in. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes (KEGG) and Reactome pathway analyses were performed to determine the DEmRNAs. LIMMA and RobustRankAggreg were used to screen for DERNAs. Node genes in the interaction network were analyzed using least absolute shrinkage and selection operator (LASSO) and Cox regression to obtain OS-related ceRNA networks. RESULTS: We identified 9 DEcircRNAs, 243 DEmiRNAs and 211 DEmRNAs. We found that a ceRNA subnetwork, based on 1 circRNA, 1 miRNA and 8 mRNAs, was closely associated with OS prognosis. Integrating the proportional hazards model and survival analysis revealed 3 independent protective factors: adenosine triphosphate (ATP)-binding cassette sub-family A member 8 (ABCA8), catalase (CAT) and C-X-C motif chemokine ligand 12 (CXCL12). CONCLUSIONS: Our study provides novel insights into circRNA-related ceRNA networks and identifies potential prognostic biomarkers of OS.
RESUMEN
This study proposes a set of generic rules to revise existing neural networks for 3D point cloud processing to rotation-equivariant quaternion neural networks (REQNNs), in order to make feature representations of neural networks to be rotation-equivariant and permutation-invariant. Rotation equivariance of features means that the feature computed on a rotated input point cloud is the same as applying the same rotation transformation to the feature computed on the original input point cloud. We find that the rotation-equivariance of features is naturally satisfied, if a neural network uses quaternion features. Interestingly, we prove that such a network revision also makes gradients of features in the REQNN to be rotation-equivariant w.r.t. inputs, and the training of the REQNN to be rotation-invariant w.r.t. inputs. Besides, permutation-invariance examines whether the intermediate-layer features are invariant, when we reorder input points. We also evaluate the stability of knowledge representations of REQNNs, and the robustness of REQNNs to adversarial rotation attacks. Experiments have shown that REQNNs outperform traditional neural networks in both terms of classification accuracy and robustness on rotated testing samples.
RESUMEN
Human in vitro fertilized embryos exhibit low developmental capabilities, and the mechanisms that underlie embryonic arrest remain unclear. Here using a single-cell multi-omics sequencing approach, we simultaneously analysed alterations in the transcriptome, chromatin accessibility and the DNA methylome in human embryonic arrest due to unexplained reasons. Arrested embryos displayed transcriptome disorders, including a distorted microtubule cytoskeleton, increased genomic instability and impaired glycolysis, which were coordinated with multiple epigenetic reprogramming defects. We identified Aurora A kinase (AURKA) repression as a cause of embryonic arrest. Mechanistically, arrested embryos induced through AURKA inhibition resembled the reprogramming abnormalities of natural embryonic arrest in terms of the transcriptome, the DNA methylome, chromatin accessibility and H3K4me3 modifications. Mitosis-independent sequential activation of the zygotic genome in arrested embryos showed that YY1 contributed to human major zygotic genome activation. Collectively, our study decodes the reprogramming abnormalities and mechanisms of human embryonic arrest and the key regulators of zygotic genome activation.