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The development of an efficient palladium probe holds significant application value, considering the detrimental impact of palladium contaminants on human health. Thus, it is critical to create a sensitive detection method. To this end, a fluorescent probe TM-TPA-Pd based on benzothianone structure was designed, using allyl carbonate as the Pd0 recognition unit. TM-TPA-Pd exhibited high sensitivity (1.4 eq), selectivity, near-infrared (NIR) fluorescence (798 nm), and low detection limit (0.46 µM) for Pd0 with a rapid "turn-on" fluorescence signal (5 min). Furthermore, TM-TPA-Pd has extremely low cytotoxicity and has been successfully applied to detecting cells and zebrafish, which has great potential for palladium detection in biological systems.
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Colorantes Fluorescentes , Paladio , Pez Cebra , Animales , Colorantes Fluorescentes/química , Paladio/química , Paladio/análisis , Humanos , Espectrometría de Fluorescencia , Límite de Detección , Espectroscopía Infrarroja Corta/métodosRESUMEN
Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease characterized by the progressive loss of motor neurons in the brain and spinal cord, and there are no effective drug treatments. Low-intensity pulsed ultrasound (LIPUS) has garnered attention as a promising noninvasive neuromodulation method. In this study, we investigate its effects on the motor cortex and underlying mechanisms using the SOD1G93A mouse model of ALS. Our results show that LIPUS treatment delays disease onset and prolongs lifespan in ALS mice. LIPUS significantly increases cerebral blood flow in the motor cortex by preserving vascular endothelial cell integrity and increasing microvascular density, which may be mediated via the ion channel TRPV4. RNA sequencing analysis reveals that LIPUS substantially reduces the expression of genes associated with neuroinflammation. These findings suggest that LIPUS applied to the motor cortex may represent a potentially effective therapeutic tool for the treatment of ALS.
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Due to the absence of definitive diagnostic criteria, there remains a lack of consensus regarding the risk assessment of central lymph node metastasis (CLNM) and the necessity for prophylactic lymph node surgery in ultrasound-diagnosed thyroid cancer. The localization of thyroid nodules is a recognized predictor of CLNM; however, quantifying this relationship is challenging due to variable measurements. In this study, we developed a differential isomorphism-based alignment method combined with a graph transformer to accurately extract localization and morphological information of thyroid nodules, thereby predicting CLNM. We collected 88,796 ultrasound images from 48,969 patients who underwent central lymph node (CLN) surgery and utilized these images to train our predictive model, ACE-Net. Furthermore, we employed an interpretable methodology to explore the factors influencing CLNM and generated a risk heatmap to visually represent the distribution of CLNM risk across different thyroid regions. ACE-Net demonstrated superior performance in 6 external multicenter tests (AUC = 0.826), surpassing the predictive accuracy of human experts (accuracy = 0.561). The risk heatmap enabled the identification of high-risk areas for CLNM, likely correlating with lymphatic metastatic pathways. Additionally, it was observed that the likelihood of metastasis exceeded 80% when the nodal margin's minimum distance from the thyroid capsule was less than 1.25 mm. ACE-Net's capacity to effectively predict CLNM and provide interpretable disease-related insights can importantly reduce unnecessary lymph node dissections by 37.9%, without missing positive cases, thus offering a valuable tool for clinical decision-making.
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Background: Endogenous retroviruses (ERVs), which blur the boundary between virus and transposable element, are genetic material derived from retroviruses and have important implications for evolution. This study examines the diversity and evolution of human endogenous retroviruses (HERVs) of the HERVL family, which has long terminal repeats (LTRs) named MLT2. Results: By probability-based sequence comparison, we uncover systematic annotation errors that conceal the true complexity and diversity of transposable elements (TEs) in the human genome. Our analysis identifies new subfamilies within the MLT2 group, proposes a refined classification scheme, and constructs new consensus sequences. We present an evolutionary analysis including phylogenetic trees that elucidate the relationships between these subfamilies and their contributions to human evolution. The results underscore the significance of accurate TE annotation in understanding genome evolution, highlighting the potential for misclassified TEs to impact interpretations of genomic studies. Availability and implementation: Not applicable.
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Environmental heterogeneity partly drives microbial succession in arthropods, while the microbial assembly mechanisms during environmental changes remain largely unknown. Here, we explored the temporal dynamics and assembly mechanisms within both bacterial and fungal communities in Liriomyza huidobrensis (Blanchard) during the transition from field to laboratory conditions. We observed a decrease in bacterial diversity and complexity of bacterial-fungal co-occurrence networks in leaf miners transitioning from wild to captive environments. Both neutral and null models revealed that stochastic processes, particularly drift (contributing over 70%), play a crucial role in governing bacterial and fungal community assembly. The relative contribution of ecological processes such as dispersal, drift, and selection varied among leaf miners transitioning from wild to captive states. Furthermore, we propose a hypothetical scenario for the assembly and succession of microbial communities in the leaf miner during the short- and long-term transition from the wild to captivity. Our findings suggest that environmental heterogeneity determines the ecological processes governing bacterial and fungal community assembly in leaf miners, offering new insights into microbiome and mycobiome assembly mechanisms in invasive pests amidst environmental change.
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Bathymodioline mussels dominate deep-sea methane seep and hydrothermal vent habitats and obtain nutrients and energy primarily through chemosynthetic endosymbiotic bacteria in the bacteriocytes of their gill. However, the molecular mechanisms that orchestrate mussel host-symbiont interactions remain unclear. Here, we constructed a comprehensive cell atlas of the gill in the mussel Gigantidas platifrons from the South China Sea methane seeps (1100 m depth) using single-nucleus RNA-sequencing (snRNA-seq) and whole-mount in situ hybridisation. We identified 13 types of cells, including three previously unknown ones, and uncovered unknown tissue heterogeneity. Every cell type has a designated function in supporting the gill's structure and function, creating an optimal environment for chemosynthesis, and effectively acquiring nutrients from the endosymbiotic bacteria. Analysis of snRNA-seq of in situ transplanted mussels clearly showed the shifts in cell state in response to environmental oscillations. Our findings provide insight into the principles of host-symbiont interaction and the bivalves' environmental adaption mechanisms.
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Simbiosis , Animales , Branquias/microbiología , Análisis de Secuencia de ARN/métodos , Bivalvos/microbiología , Bivalvos/genética , Mytilidae/genética , Mytilidae/microbiología , Bacterias/genéticaRESUMEN
RATIONALE AND OBJECTIVES: To validate the image quality of low-dose ultra-high-resolution (UHR) scanning mode of photon-counting detector CT (PCD-CT) for visceral artery computed tomography angiography (CTA). MATERIAL AND METHODS: We prospectively enrolled 57 patients each in the full dose (FD) and low-dose (LD) protocols, respectively, to undergo abdominal CT scans using the UHR mode on a PCD-CT system (NAEOTOM Alpha), between April 2023 and September 2023. Both the FD data and LD data were then reconstructed into two series of images: (a) 0.2 mm slice thickness, reconstruction kernel Bv48, quantum iterative reconstruction (QIR) 4; (b)1 mm slice thickness, Bv40, QIR 3. The signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) of seven arteries were objectively measured. The image noise, vessel sharpness, overall quality, and visibility of nine arteries were subjectively assessed by three radiologists. RESULTS: The SNRs and CNRs of 0.2 mm reconstruction set was inferior to that of 1 mm reconstruction set (p < 0.001 for all the arteries and noise), however, the image quality of 0.2 mm reconstruction set was higher than that of 1 mm reconstruction set in qualitative evaluation especially for tiny arteries in Volume-rendered (VR) image (p < 0.001). The SNRs and CNRs were not significantly higher for FD group than LD group on the same slice thickness except for SNRs of common hepatic artery, splenic artery and bilateral renal arteries in 0.2 mm reconstruction set. In the comparison on image quality between normal weight and overweight patients within the same reconstruction set, the results showed that low-dose scan did not significantly impact the image quality in overweight patients. The ratings of visibility of nine visceral arteries were not significantly different among FD and LD at the same thickness reconstruction set except for superior mesenteric artery (p = 0.002 and 0.007 for 0.2 mm and 1 mm reconstruction set in axial image; p = 0.002 and 0.007 for 0.2 mm and 1 mm reconstruction set in coronal image, respectively) and left gastric artery (p = 0.002 and p < 0.001 for 0.2 mm and 1 mm reconstruction set in VR image, respectively). CONCLUSION: The low-dose UHR scanning mode of PCD-CT has proven to be adequate for the clinical evaluation of visceral arteries. Utilizing a reconstruction with a slice thickness of 0.2 mm could enhance arterial depiction, particularly for small vessels.
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Aiming to improve the retrieval rate of retrievable vena cava filters (RVCF) and extend its dwelling time in vivo, a novel hydrogel coating loaded with 10 mg/mL heparin and 30 mg/mL cyclodextrin/paclitaxel (PTX) inclusion complex (IC) was prepared. The drug-release behavior in the phosphate buffer solution demonstrated both heparin and PTX could be sustainably released over approximately two weeks. Furthermore, it was shown that the hydrogel-coated RVCF (HRVCF) with 10 mg/mL heparin and 30 mg/mL PTX IC effectively extended the blood clotting time to above the detection limit and inhibited EA.hy926 and CCC-SMC-1 cells' proliferation in vitro compared to the commercially available bare RVCF. Both the HRVCF and the bare RVCF were implanted into the vena cava of sheep and retrieved at at 2nd and 4th week after implantation, revealing that the HRVCF had a significantly higher retrieval rate of 67 % than the bare RVCF (0 %) at 4th week. Comprehensive analyses, including histological, immunohistological, and immunofluorescent assessments of the explanted veins demonstrated the HRVCF exhibited anti-hyperplasia and anticoagulation properties in vivo, attributable to the hydrogel coating, thereby improving the retrieval rate in sheep. Consequently, the as-prepared HRVCF shows promising potential for clinical application to enhance the retrieval rates of RVCFs.
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Background: The associations between blood heavy metal levels and latent tuberculosis infection (LTBI) have not been fully elucidated. The aim of this study was to investigate the potential association between blood heavy metal levels and LTBI in adults using National Health and Nutrition Examination Survey data from 2011 to 2012. Methods: We enrolled 1710 participants in this study, and compared the baseline characteristics of participants involved. Multivariate logistic regression analysis, restricted cubic splines (RCS) analysis, along with subgroup analysis and interaction tests were utilized to explore the association between blood manganese (Mn) level and LTBI risk. Results: Participants with LTBI had higher blood Mn level compared to non-LTBI individuals (p < 0.05), while the levels of lead, cadmium, total mercury, selenium, copper, and zinc did not differ significantly between the two groups (p > 0.05). In the fully adjusted model, a slight increase in LTBI risk was observed with each 1-unit increase in blood Mn level (OR = 1.00, 95% CI: 1.00-1.01, p = 0.02). Participants in the highest quartile of blood Mn level had a threefold increase in LTBI risk compared to those in the lowest quartile (OR = 4.01, 95% CI: 1.22-11.33, p = 0.02). RCS analysis did not show a non-linear relationship between blood Mn level and LTBI (non-linear p-value = 0.0826). Subgroup analyses and interaction tests indicated that age, alcohol consumption, and income-to-poverty ratio significantly influenced LTBI risk (interaction p-values<0.05). Conclusion: Individuals with LTBI had higher blood Mn level compared to non-LTBI individuals, and higher blood Mn level associated with increased LTBI risk.
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Tuberculosis Latente , Manganeso , Encuestas Nutricionales , Humanos , Tuberculosis Latente/sangre , Tuberculosis Latente/epidemiología , Manganeso/sangre , Masculino , Femenino , Adulto , Persona de Mediana Edad , Estados Unidos/epidemiología , Factores de RiesgoRESUMEN
The white pollution caused by unsustainable materials is a significant challenge around the globe. Here, a novel and fully biobased polybutyrolactam (PBY) nanofiber membrane was fabricated via the electrospinning method. As-spun PBY nanofiber membranes have good thermal stability, high porosity of up to 71.94%, and excellent wetting behavior. The biodegradability in soil, UV aging irradiation, and seawater was investigated. The PBY nanofiber membrane is almost completely degraded in the soil within 80 days, showing excellent degradability. More interestingly, γ-aminobutyric acid, as a healthcare agent with intrinsic hypotensive, tranquilizing, diuretic, and antidiabetic efficacy, can be detected in the degradation intermediates. In addition, the PBY nanofiber membrane also exhibits antibacterial ability against Escherichia coli. As a fully biomass-derived material, the PBY membrane has excellent biodegradable performance in various environments as well as negligible cytotoxicity and commendable cell proliferation. Our PBY nanofiber membrane shows great potential as biodegradable packaging and in vitro healthcare materials.
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CT-based bronchial tree analysis is a key step for the diagnosis of lung and airway diseases. However, the topology of bronchial trees varies across individuals, which presents a challenge to the automatic bronchus classification. To solve this issue, we propose the Bronchus Classification Network (BCNet), a structure-guided framework that exploits the segment-level topological information using point clouds to learn the voxel-level features. BCNet has two branches, a Point-Voxel Graph Neural Network (PV-GNN) for segment classification, and a Convolutional Neural Network (CNN) for voxel labeling. The two branches are simultaneously trained to learn topology-aware features for their shared backbone while it is feasible to run only the CNN branch for the inference. Therefore, BCNet maintains the same inference efficiency as its CNN baseline. Experimental results show that BCNet significantly exceeds the state-of-the-art methods by over 8.0% both on F1-score for classifying bronchus. Furthermore, we contribute BronAtlas: an open-access benchmark of bronchus imaging analysis with high-quality voxel-wise annotations of both anatomical and abnormal bronchial segments. The benchmark is available at link1.
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Objective: To elucidate the role of circVRK1 and its interaction with miR-4428 in regulating proliferation and apoptosis in acute lymphoblastic leukemia (ALL) cells. Methods: KOCL44 ALL cells were cultured in vitro, and experimental groups included pcDNA, pcDNA-circVRK1, anti-miR-NC, anti-miR-4428, si-NC, si-circVRK1, pcDNA-circVRK1+miR-NC, and pcDNA-circVRK1+miR-4428. The expression levels of circVRK1 and miR-4428 were detected using qRT-PCR. CCK-8 assays and flow cytometry were used to assess cell proliferation and apoptosis, respectively. The dual luciferase reporter assays were employed to investigate the interaction between circVRK1 and miR-4428, with groups categorized as WT-circVRK1+miR-NC, WT-circVRK1+miR-4428, MUT-circVRK1+miR-NC, and MUT-circVRK1+ miR-4428. Western blotting was utilized to detect the expression levels of Ki-67, cleaved caspase-3, and cleaved caspase-9 proteins. Results: Compared to the pcDNA group, circVRK1 expression was up-regulated in the pcDNA-circVRK1 group (P<0.05). Compared to transfection with pcDNA or anti-miR-NC, transfection with pcDNA-circVRK1 or anti-miR-4428 led to decreased cell viability and Ki-67 protein levels in KOCL44 cells (P<0.05), and increased apoptosis rates and levels of cleaved caspase-3 and cleaved caspase-9 (P<0.05). circVRK1 was found to negatively regulate miR-4428 expression, with this effect observed only in the WT-circVRK1 group. miR-4428 levels were lower in the pcDNA-circVRK1 group compared to the pcDNA group (P<0.05) and higher in the si-circVRK1 group compared to the si-NC group (P<0.05). Co-transfection with pcDNA-circVRK1+miR-4428 resulted in increased cell viability (P<0.05) and Ki-67 expression (P<0.05), and decreased apoptosis rates and levels of cleaved caspase-3 and cleaved caspase-9 (P<0.05) compared to co-transfection with pcDNA-circVRK1+miR-NC. Conclusion: Overexpression of circVRK1 reduces the proliferation ability of acute ALL cells and induces cell apoptosis by downregulating miR-4428 expression.
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Apoptosis , Proliferación Celular , MicroARNs , Leucemia-Linfoma Linfoblástico de Células Precursoras , ARN Circular , MicroARNs/genética , MicroARNs/metabolismo , Humanos , Apoptosis/genética , Proliferación Celular/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , Línea Celular Tumoral , Caspasa 3/metabolismo , Caspasa 3/genética , Caspasa 9/metabolismo , Caspasa 9/genéticaRESUMEN
This study investigated the effects of the application of glycine (Gly) and Pediococcus pentosaceus R1(Pp), alone or in combination, on the physicochemical properties, oxidative stability, and taste quality of Harbin dry sausages. The results demonstrated that after nine days of fermentation, the Gly + Pp group exhibited significantly (P < 0.05) lower moisture content (19.04%), water activity (0.686), and pH (4.78) values, alongside notably (P < 0.05) higher lactic acid bacteria count (8.11 log CFU/g sausage) and redness value (17.2), compared to the other three groups (P < 0.05). In addition, the dry sausages in the Gly + Pp group exhibited the lowest peroxide value (0.34 meq/kg sausage), thiobarbituric acid reactive substances (0.46 MAD/kg sausage), and protein carbonyl content (1.26 nmol/kg protein) during fermentation, followed by the Gly group, Pp group, and control group. Electronic tongue (e-tongue) and sensory evaluations revealed that the combined treatment with P. pentosaceus R1 and Gly resulted in superior taste characteristics. Besides, partial least squares regression (PLSR) analysis illustrated that the taste qualities characterized using the e-tongue were accordant with the sensory evaluation consequences, and total free amino acids (FAAs) and organic acids contributed to the dry sausages' taste properties. In conclusion, the combined application of Gly and P. pentosaceus R1 enhanced the physicochemical properties, oxidative stability, and taste profile of Harbin dry sausages.
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Fermentación , Glicina , Productos de la Carne , Pediococcus pentosaceus , Gusto , Productos de la Carne/análisis , Productos de la Carne/microbiología , Glicina/farmacología , Animales , Humanos , Porcinos , Concentración de Iones de Hidrógeno , Oxidación-Reducción , Probióticos , Masculino , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis , Adulto , Nariz Electrónica , FemeninoRESUMEN
BACKGROUND: Sepsis-associated liver injury (SLI) is a severe and prevalent complication of sepsis. AIM: To explore the literature on SLI via a bibliometric approach. METHODS: Reviews and articles correlated with SLI published from January 1, 2000 to October 28, 2023 were searched from the Web of Science Core Collection. Then, the searched data were analyzed using VOSviewer, CiteSpace, and R language. RESULTS: There were 787 publications involved in this paper, comprising 745 articles and 42 reviews. China, the United States, and Germany are the primary publication sources in this area. Studies related to SLI primarily focused on mechanisms of pathogenesis, as evidenced by analyzing keywords, references, and the counting of original research. These studies mainly involved tumor necrosis factor alpha, inflammation, oxidative stress, and nuclear factor-kappa B. CONCLUSION: There is significant growth in the research on SLI. Current investigations primarily involve basic experiments that aimed at uncovering pathogenic mechanisms. According to the analyzed literature, the identified pathogenic mechanisms and potential therapeutic targets serve as the foundation for translating findings from basic research to clinical applications.
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Bibliometría , Sepsis , Humanos , Sepsis/complicaciones , Sepsis/etiología , Hepatopatías/etiología , Estrés Oxidativo , Hígado/lesiones , Hígado/patologíaRESUMEN
Marine mussels inhabit a wide range of ocean depths, necessitating unique adaptations to cope with varying hydrostatic pressures. This study investigates the transcriptomic responses and evolutionary adaptations of the deep-sea mussel Gigantidas platifrons and the shallow-water mussel Mytilus galloprovincialis to high hydrostatic pressure (HHP) conditions. By exposing atmospheric pressure (AP) acclimated G. platifrons and M. galloprovincialis to HHP, we aim to simulate extreme environmental challenges and assess their adaptive mechanisms. Through comparative transcriptomic analysis, we identified both conserved and species-specific mechanisms of adaptation, with a notable change in gene expression associated with immune system, substance transport, protein ubiquitination, apoptosis, lipid metabolism and antioxidant processes in both species. G. platifrons demonstrated an augmented lipid metabolism, whereas M. galloprovincialis exhibited a dampened immune function. Additionally, the expressed pattern of deep-sea mussel G. platifrons were more consistent than shallow-water mussel M. galloprovincialis under hydrostatic pressures changed conditions which corresponding the long-term living stable deep-sea environment. Moreover, evolutionary analysis pinpointed positively selected genes in G. platifrons that are linked to transmembrane transporters, DNA repair and replication, apoptosis, ubiquitination which are important to cell structural integrity, substances transport, and cellular growth regulation. This indicates a specialized adaptation strategy in G. platifrons to cope with the persistent HHP conditions of the deep sea. These results offer significant insights into the molecular underpinnings of mussel adaptation to varied hydrostatic conditions and enhance our comprehension of the evolutionary forces driving their depth-specific adaptations.
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Presión Hidrostática , Transcriptoma , Animales , Adaptación Fisiológica , Evolución Biológica , Mytilus/fisiología , Mytilus/genética , Bivalvos/genética , Bivalvos/fisiologíaRESUMEN
Residual chlorine from widespread disinfection processes forms byproducts in water that are harmful to humans and ecosystems. Portable sensors are essential tools for the on-site monitoring of residual chlorine in environmental samples. Here, an inexpensive colorimetric sensor was developed by grafting via amidation the chromogen orthotolidine (OTO) to the surface of a TEMPO-oxidized cellulose filter paper (O-TOFP). A thorough characterization of the sensor strip demonstrated that it was highly stable and that it could be stored for a long period before usage. O-TOFP had a fast response time of 30 s, was highly selective for residual chlorine ions (ClO-) with an accuracy of at least 95 %, and exhibited an excellent limit of detection of only 0.045 mg/L when combined with smartphone image acquisition. With its many positive features, the easy-to-use and robust O-TOFP sensor described here could become a useful tool for the determination of residual chlorine in different water samples.
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Celulosa Oxidada , Cloro , Colorimetría , Colorimetría/métodos , Cloro/análisis , Cloro/química , Celulosa Oxidada/análisis , Celulosa Oxidada/química , Límite de Detección , Contaminantes Químicos del Agua/análisis , PapelRESUMEN
Sweet potato starch is in high demand globally for food and industry. However, starch content is negatively correlated with fresh yield. It is urgent to uncover the genetic basis and molecular mechanisms underlying the starch yield of sweet potato. Here we systematically explore source-sink synergy-mediated sweet potato starch yield formation: the production, loading, and transport of photosynthates in leaves, as well as their unloading and allocation in storage roots, lead to starch content divergence between sweet potato varieties. Moreover, we find that six haplotypes of IbPMA1 encoding a plasma membrane H+-ATPase are significantly linked with starch accumulation. Overexpression of IbPMA1 in sweet potato results in significantly increased starch and sucrose contents, while its knockdown exhibits an opposing effect. Furthermore, a basic helix-loop-helix (bHLH) transcription factor IbbHLH49 directly targets IbPMA1 and activates its transcription. Overexpression of IbbHLH49 notably improves source-sink synergy-mediated fresh yield and starch accumulation in sweet potato. Both IbbHLH49 and IbPMA1 substantially influence sugar transport and starch biosynthesis in source and sink tissues. These findings expand our understanding of starch yield formation and provide strategies and candidate genes for high starch breeding in root and tuber crops.
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Regulación de la Expresión Génica de las Plantas , Ipomoea batatas , Hojas de la Planta , Proteínas de Plantas , Raíces de Plantas , Almidón , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Ipomoea batatas/crecimiento & desarrollo , Almidón/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Raíces de Plantas/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/genética , Hojas de la Planta/metabolismo , Hojas de la Planta/genética , Plantas Modificadas Genéticamente , Haplotipos , Sacarosa/metabolismo , ATPasas de Translocación de Protón/metabolismo , ATPasas de Translocación de Protón/genéticaRESUMEN
Dynamic environments pose great challenges for expensive optimization problems, as the objective functions of these problems change over time and thus require remarkable computational resources to track the optimal solutions. Although data-driven evolutionary optimization and Bayesian optimization (BO) approaches have shown promise in solving expensive optimization problems in static environments, the attempts to develop such approaches in dynamic environments remain rarely explored. In this article, we propose a simple yet effective meta-learning-based optimization framework for solving the expensive dynamic optimization problems. This framework is flexible, allowing any off-the-shelf continuously differentiable surrogate model to be used in a plug-in manner, either in data-driven evolutionary optimization or BO approaches. In particular, the framework consists of two unique components: 1) the meta-learning component, in which a gradient-based meta-learning approach is adopted to learn experience (effective model parameters) across different dynamics along the optimization process and 2) the adaptation component, where the learned experience (model parameters) is used as the initial parameters for fast adaptation in the dynamic environment based on few shot samples. By doing so, the optimization process is able to quickly initiate the search in a new environment within a strictly restricted computational budget. Experiments demonstrate the effectiveness of the proposed algorithm framework compared to several state-of-the-art algorithms on common benchmark test problems under different dynamic characteristics.
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Objective: To validate the feasibility of ultrasound in assessing the curative effect of botulinum toxin type A (BTXA) in treating hypertrophic scar (HS). Methods: Eight healthy New Zealand long-eared rabbits were utilized in the study. Four wounds, each measuring 1.0 cm in diameter, were created on both ears of each rabbit. Immediately after surgery, each of these wounds received an injection containing a distinct concentration of BTXA. On postoperative week 6, scar thickness, vascularity, and hardness were assessed based on high frequency ultrasound (HFUS), superb microvascular imaging (SMI), shear wave elastography (SWE), Masson staining, and immunohistochemical staining for CD31. Results: All wounds healed well, and HSs formed after 6 weeks post-surgery. Scar thickness based on HFUS presented a significant decrease with increasing BTXA concentration (p < 0.05), aligning with the gross morphology. Simultaneously, scar stiffness, evaluated using SWE, showed a significant decrease in accordance with the variation of the collagen volume fraction, which refers to the ratio of the collagen positive area to the total area (p < 0.05). Although the vascularity index obtained by SMI did not exhibit a statistically significant change across different BTXA concentrations, this technique effectively illustrated the microvascular perfusion in HS. Immunohistochemical staining for CD31 revealed that BTXA inhibited angiogenesis. Conclusion: HFUS and SWE displayed excellent performance in evaluating HS thickness and stiffness. SMI showed a good performance in reflecting microvascular signals in HS. These ultrasound techniques have great potential in assessing the therapeutic effect of BTXA in HS.