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PURPOSE: To develop a deep learning (DL) model that can simultaneously detect lateral and medial collateral ligament injuries of the ankle, aiding in the diagnosis of chronic ankle instability (CAI), and assess its impact on clinicians' diagnostic performance. METHODS: DL models were developed and externally validated on retrospectively collected ankle magnetic resonance imaging (MRI) between April 2016 and March 2022 respectively at 3 centers. Included patients had confirmed diagnoses of CAI through arthroscopy, as well as individuals who had undergone MRI and physical examinations that ruled out ligament injuries. DL models were constructed based on a multilabel paradigm. A transformer-based multilabel DL model (AnkleNet) was developed and compared with 4 convolution neural network (CNN) models. Subsequently, a reader study was conducted to evaluate the impact of model assistance on clinicians when diagnosing challenging cases: identifying rotational CAI (RCAI). Diagnostic performance was assessed using area under the receiver operating characteristic curve (AUC). RESULTS: Our transformer-based model achieved AUCs of 0.910 and 0.892 for detecting lateral and medial collateral ligament injury, respectively, both of which were significantly higher than those of CNN-based models (all P < .001). In terms of further CAI diagnosis, there was a macro-average AUC of 0.870 and a balanced accuracy of 0.805. The reader study indicated that incorporation with our model significantly enhanced the diagnostic accuracy of clinicians (P = .042), particularly junior clinicians, and led to a reduction in diagnostic variability. The code of the model can be accessed at https://github.com/ChiariRay/AnkleNet. CONCLUSIONS: Our transformer-based model was able to detect lateral and medial collateral ligament injuries based on MRI and outperformed CNN-based models, demonstrating a promising performance in diagnosing CAI, especially patients with RCAI. CLINICAL RELEVANCE: Developing such an algorithm can improve the diagnostic performance of clinicians, aiding in identifying patients who would benefit from arthroscopy, such as patients with RCAI.
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Glycosylation plays a pivotal role in the intricate landscape of human cholangiocarcinoma (CCA), actively participating in key pathophysiological processes driving tumor progression. Among the various glycosylation modifications, O-linked ß-N-acetyl-glucosamine modification (O-GlcNAcylation) emerges as a dynamic regulator influencing diverse tumor-associated biological activities. In this study, we employed a state-of-the-art chemical proteomic approach to analyze intact glycopeptides, unveiling the critical role of O-GlcNAcylation in orchestrating Keratin 18 (K18) and its interplay with tricarboxylic acid (TCA) cycle enzymes, specifically isocitrate dehydrogenases (IDHs), to propel CCA progression. Our findings shed light on the mechanistic intricacies of O-GlcNAcylation, revealing that site-specific modification of K18 on Ser 30 serves as a stabilizing factor, amplifying the expression of cell cycle checkpoints. This molecular event intricately fosters cell cycle progression and augments cellular growth in CCA. Notably, the interaction between O-GlcNAcylated K18 and IDHs orchestrates metabolic reprogramming by down-regulating citrate and isocitrate levels while elevating α-ketoglutarate (α-KG). These metabolic shifts further contribute to the overall tumorigenic potential of CCA. Our study thus expands the current understanding of protein O-GlcNAcylation and introduces a new layer of complexity to post-translational control over metabolism and tumorigenesis.
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African swine fever (ASF) is a lethal disease caused by ASF virus (ASFV), severely impacting the global swine industry. Though nuclear acid-based detection methods are reliable, they are laboratory-dependent. In this study, we developed a device-independent, user friendly and cost-effective quantum dots based immunochromatographic strip (QDs-ICS) with high specificity and sensitivity for the rapid and on-site detection of ASFV antigen. For the preparation of the QDs-ICS, we generated a monoclonal antibody (mAb) mAb-8G8 and polyclonal antibody (pAb) against ASFV-p72 protein. The pAb was labelled with QDs to be used as the detection probe and the mAb-8G8 was coated on the nitrocellulose membrane as the test line. Our results proved that the strip displayed no cross-reactivity with other swine viruses and detection limit of the QDs-ICS was down to 1 ng/mL for the ASFV-p72 protein with great reproducibility. The strip also exhibited high stability with a storage period up to 12 months under room temperature. Twenty blind samples and one hundred clinical samples were examined by the QDs-ICS, conventional PCR and real-time PCR method, respectively. Results showed that the agreement rate between the QDs-ICS and PCR method was 100%, and the agreement rate between the strip and real-time PCR was 94%. The novel QDs-ICS developed here would be an effective tool for on-site detection of ASFV.
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Virus de la Fiebre Porcina Africana , Fiebre Porcina Africana , Anticuerpos Monoclonales , Anticuerpos Antivirales , Antígenos Virales , Cromatografía de Afinidad , Puntos Cuánticos , Sensibilidad y Especificidad , Virus de la Fiebre Porcina Africana/aislamiento & purificación , Virus de la Fiebre Porcina Africana/inmunología , Virus de la Fiebre Porcina Africana/genética , Animales , Fiebre Porcina Africana/diagnóstico , Fiebre Porcina Africana/virología , Fiebre Porcina Africana/inmunología , Porcinos , Anticuerpos Monoclonales/inmunología , Anticuerpos Antivirales/inmunología , Cromatografía de Afinidad/métodos , Antígenos Virales/análisis , Antígenos Virales/inmunología , Reproducibilidad de los Resultados , Tiras ReactivasRESUMEN
BACKGROUND: Unicompartmental knee arthroplasty is an effective treatment for knee osteoarthritis, but it has the risk of failure, and the installation position of the prosthesis is one of the factors affecting the failure. There are few biomechanical studies on the installation angle of unicompartmental knee prosthesis. METHODS: Constructed a finite element model of a normal human knee joint, and the validity of the model was verified by stress and front anterior methods. The mobile-bearing unicompartmental knee arthroplasty femoral prosthesis was placed at 3° intervals from 0° sagittal plane to 15° flexion, and - 2° and 17°were established, and observing the biomechanical changes of components. FINDINGS: Maximum peak stresses occurred at a sagittal mounting angle of -2° for the insert and the contralateral meniscus, with the tibia showing a maximum at 17° sagittal and the tibial prosthesis stress maximum occurring at 6° sagittal. As the sagittal plane angle of the femoral prosthesis increases and the osteotomy distance extends posteriorly, more bone is amputated during the osteotomy. The ratio of the distance from the tip of the anterior intramedullary nail to the anterior end of the osteotomy to the total anteroposterior length of the sagittal osteotomy ranged from 43.2% to 44.6%. INTERPRETATION: In this paper, the more appropriate sagittal mounting position for the femoral prosthesis is between 9 and 12°, based on the amount of osteotomy and the peak stress of each component in a standing position.
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Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Osteoartritis de la Rodilla , Humanos , Artroplastia de Reemplazo de Rodilla/métodos , Análisis de Elementos Finitos , Fenómenos Biomecánicos , Articulación de la Rodilla/cirugía , Osteoartritis de la Rodilla/cirugía , Tibia/cirugíaRESUMEN
Echinococcus granulosus (Eg) and Echinococcus multilocularis (Em) are the two most widely prevalent types of echinococcosis. Several diagnostic methods have been developed for detecting Eg and Em. However, some limitations, such as being time-consuming, needing expensive instruments, or exhibiting low sensitivity, make these methods unsuitable for on-site detection. In this study, a dual-RPA assay was established to detect and differentiate Eg and Em. The primer concentration ratio, reaction time, and reaction temperature of the dual-RPA were optimized. The result showed that the primer concentration ratio of Eg:Em was 400 nM:400 nM, and the best amplification efficiency was obtained by reacting at 38 °C for 20 min. The sensitivity, specificity, and repeatability of the assay were also tested. The assay's detection limit for both Eg and Em was 10 copies/µL. The assay showed reasonable specificity by testing ten parasitic nucleic acids. The assay's intra- and inter-batch coefficients of variation were below 10%, which indicates robust reproducibility of the assay. Finally, to validate the performance of the dual-RPA assay, it was compared with real-time PCR by using 86 clinical nucleic acid samples. The coincidence rate of Eg between dual-RPA and TaqMan real-time PCR was 96.51%, and the coincidence rate of Em between dual-RPA and TaqMan real-time PCR was 98.84%, indicating its potential for accurate clinical diagnosis. Therefore, this study established a rapid and sensitive dual-RPA assay that can rapidly detect and differentiate Eg and Em in one reaction tube and provided a new assay for the detection of echinococcosis in the field.
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Equinococosis , Echinococcus granulosus , Animales , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Equinococosis/diagnóstico , Echinococcus granulosus/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Recombinasas , Técnicas de Amplificación de Ácido Nucleico/métodosRESUMEN
In this study, we successfully developed a nanobody-based double antibody sandwich ELISA kit for the detection of clinical serum C-reactive protein (CRP) by using two novel CRP specific nanobodies. The developed method exhibited a linear detection range of approximately 6-200 ng/mL, with a detection limit of 1 ng/mL. Furthermore, the method demonstrated excellent specificity, as there was no cross-reactivity with interfering substances such as total bilirubin and hemoglobin and so on. To assess reproducibility, independent measurements of the samples were conducted under experimental conditions, resulting in intra- and inter-batch coefficients of variation below 10% and a recovery rate of 93%-102%. These results indicate robust reproducibility of the method. To evaluate the performance of the developed kit, we collected 90 clinical samples for correlation analysis with commercial kits. The results showed a high correlation coefficient value (R2) of 0.98, indicating accurate concordance between the developed and commercial kits. In conclusion, our study successfully developed a nanobody-based double antibody sandwich ELISA kit to detect clinical serum CRP. The utilization of nanobodies represents a significant advancement in the field of CRP immunoassay development. The developed kit demonstrates excellent performance characteristics and holds promise for clinical applications.
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Proteína C-Reactiva , Ensayo de Inmunoadsorción Enzimática , Anticuerpos de Dominio Único , Ensayo de Inmunoadsorción Enzimática/métodos , Proteína C-Reactiva/análisis , Humanos , Anticuerpos de Dominio Único/inmunología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Límite de DetecciónRESUMEN
OBJECTIVE: To elucidate the molecular mechanism of overloading-induced osteoarthritis (OA) and to find a novel therapeutic target. METHODS: We utilized human cartilage specimens, mouse chondrocytes, a destabilization of the medial meniscus (DMM) mouse model, and a mouse hindlimb weight-bearing model to validate the role of overloading on chondrocyte senescence and OA development. Then, we observed the effect of PIEZO1-miR-155-5p-GDF6-SMAD2/3 signaling axis on the preservation of joint metabolic homeostasis under overloading in vivo, in vitro and ex vivo by qPCR, Western blot, enzyme-linked immunosorbent assay (ELISA), immunohistochemistry, immunofluorescence, SA-ß-gal staining, CCK8 assay, et al. Finally, we verified the therapeutic effects of intra-articular injection of miR-155-5p inhibitor or recombinant GDF6 on the murine overloading-induced OA models. RESULTS: Chondrocytes sensesed the mechanical overloading through PIEZO1 and up-regulated miR-155-5p expression. MiR-155-5p mimics could copy the effects of overloading-induced chondrocyte senescence and OA. Additionally, miR-155-5p could suppress the mRNA expression of Gdf6-Smad2/3 in various tissues within the joint. Overloading could disrupt joint metabolic homeostasis by downregulating the expression of anabolism indicators and upregulating the expression of catabolism indicators in the chondrocytes and synoviocytes, while miR-155-5p inhibition or GDF6 supplementation could exert an antagonistic effect by preserving the joint homeostasis. Finally, in the in vivo overloading models, intra-articular injection of miR-155-5p inhibitor or recombinant GDF6 could significantly mitigate the severity of impending OA and lessened the progression of existing OA. CONCLUSION: GDF6 overexpression or miR-155-5p inhibition could attenuate overloading-induced chondrocyte senescence and OA through the PIEZO1-miR-155-5p-GDF6-SMAD2/3 signaling pathway. Our study provides a new therapeutic target for the treatment of overloading-induced OA.
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MicroARNs , Osteoartritis , Animales , Humanos , Ratones , Apoptosis , Condrocitos/metabolismo , Factor 6 de Diferenciación de Crecimiento/metabolismo , Factor 6 de Diferenciación de Crecimiento/farmacología , Factor 6 de Diferenciación de Crecimiento/uso terapéutico , Canales Iónicos/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Osteoartritis/metabolismo , Transducción de Señal , Proteína Smad2/metabolismo , Estrés MecánicoRESUMEN
Covalent organic frameworks (COFs) are promising iodine adsorbents. For improved performances, it is critical and essential to fundamentally understand the underlying mechanism. Here, using the operando dark-field optical microscopy (DFM) imaging technique, the observation of an extraordinary structure shrinkage of 2D triphenylbenzene (TPB)-dimethoxyterephthaldehyde (DMTP)-COF upon the adsorption of I2 vapor at the single-particle resolution is reported. Combining single-particle DFM imaging with other experimental and theoretical methods, it is revealed that the shrinkage mechanism of the TPB-DMTP-COF is attributed to the I2 sorption-induced synchronous skeleton-pore interactions. The redox reaction of I2 and TPB-DMTP-COF yields some cationic skeletons and I3 - species, which triggers the multi-directional halogen-bonding interactions of I2 and I3 - as well as strong cation-π interactions between neutral and cationic skeletons, accompanying the synchronous in-plane skeleton shrinking in the xy plane and compact out-of-plane layer packing in the z-direction. This understanding of the synchronous action between the skeleton and pore breaks the perspective on the structure robustness of 2D COFs with excellent stability during the I2 uptake, which offers pivotal guidance for the rational design and creation of advanced microporous adsorbents.
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Peste des petits ruminants (PPR) is an acute, contact infectious disease caused by the small ruminant morbillivirus (SRMV), and its morbidity in goats and sheep can be up to 100% with significant mortality. Nanobody generated from camelid animals such as alpaca has attracted wide attention because of its unique advantages compared with conventional antibodies. The main objective of this study was to produce specific nanobodies against SRMV and identify its characteristics. To obtain the coding gene of SRMV-specific nanobodies, we first constructed an immune phage-displayed library from the VHH repertoire of alpaca that was immunized with SRMV-F and -H proteins. By using phage display technology, the target antigen-specific VHHs can be obtained after four consecutive rounds of biopanning. Results showed that the size of this VHH library was 2.26 × 1010 CFU/mL and the SRMV-F and -H specific phage particles were greatly enriched after four rounds of biopanning. The positive phage clones were selected and sequenced, and total of five independent different sequences of SRMV-specific nanobodies were identified. Subsequently, the DNA fragments of the five nanobodies were cloned into E. coli BL21(DE3), respectively, and three of them were successfully expressed and purified. Specificity and affinity towards inactivated SRMV of these purified nanobodies were then evaluated using the ELISA method. Results demonstrated that NbSRMV-1-1, NbSRMV-2-10, and NbSRMV-1-21 showed no cross-reactivity with other antigens, such as inactivated BTV, inactivated FMDV, His-tag labeled protein, and BSA. The ELISA titer of these three nanobodies against inactivated SRMV was up to 1:1000. However, only NbSRMV-1-21 displayed SRMV neutralizing activity at a maximum dilution of 1:4. The results indicate that the nanobodies against SRMV generated in this study could be useful in future applications. This study provided a novel antibody tool and laid a foundation for the treatment and detection of SRMV.
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Bacteriófagos , Camélidos del Nuevo Mundo , Peste de los Pequeños Rumiantes , Virus de la Peste de los Pequeños Rumiantes , Anticuerpos de Dominio Único , Animales , Ovinos , Anticuerpos de Dominio Único/genética , Escherichia coli/genética , Virus de la Peste de los Pequeños Rumiantes/genética , Peste de los Pequeños Rumiantes/prevención & control , Anticuerpos , Antígenos , CabrasRESUMEN
BACKGROUND: Magnetic resonance imaging (MRI) is the preferred imaging modality for diagnosing knee disease. Segmentation of the knee MRI images is essential for subsequent quantification of clinical parameters and treatment planning for knee prosthesis replacement. However, the segmentation remains difficult due to individual differences in anatomy, the difficulty of obtaining accurate edges at lower resolutions, and the presence of speckle noise and artifacts in the images. In addition, radiologists must manually measure the knee's parameters which is a laborious and time-consuming process. PURPOSE: Automatic quantification of femoral morphological parameters can be of fundamental help in the design of prosthetic implants for the repair of the knee and the femur. Knowledge of knee femoral parameters can provide a basis for femoral repair of the knee, the design of fixation materials for femoral prostheses, and the replacement of prostheses. METHODS: This paper proposes a new deep network architecture to comprehensively address these challenges. A dual output model structure is proposed, with a high and low layer fusion extraction feature module designed to extract rich features through the cross-fusion mechanism. A multi-scale edge information extraction spatial feature module is also developed to address the boundary-blurring problem. RESULTS: Based on the precise automated segmentation results, 10 key clinical parameters were automatically measured for a knee femoral prosthesis replacement program. The correlation coefficients of the quantitative results of these parameters compared to manual results all achieved at least 0.92. The proposed method was extensively evaluated with MRIs of 78 patients' knees, and it consistently outperformed other methods used for segmentation. CONCLUSIONS: The automated quantization process produced comparable measurements to those manually obtained by radiologists. This paper demonstrates the viability of automatic knee MRI image segmentation and quantitative analysis with the proposed method. This provides data to support the accuracy of assessing the progression and biomechanical changes of osteoarthritis of the knee using an automated process, thus saving valuable time for the radiologists and surgeons.
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Procesamiento de Imagen Asistido por Computador , Articulación de la Rodilla , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Articulación de la Rodilla/diagnóstico por imagen , Rodilla/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Fémur/diagnóstico por imagenAsunto(s)
Enfermedad Crítica , Riñón , Humanos , Incidencia , Pruebas de Función Renal , Factores de Riesgo , Antibacterianos , CreatininaRESUMEN
Metabolic oligosaccharide engineering (MOE) is a classical chemical approach to perturb, profile and perceive glycans in physiological systems, but probes upon bioorthogonal reaction require accessibility and the background signal readout makes it challenging to achieve glycan quantification. Here we develop SeMOE, a selenium-based metabolic oligosaccharide engineering strategy that concisely combines elemental analysis and MOE,enabling the mass spectrometric imaging of glycome. We also demonstrate that the new-to-nature SeMOE probes allow for detection, quantitative measurement and visualization of glycans in diverse biological contexts. We also show that chemical reporters on conventional MOE can be integrated into a bifunctional SeMOE probe to provide multimodality signal readouts. SeMOE thus provides a convenient and simplified method to explore the glyco-world.
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Selenio , Polisacáridos/metabolismo , Oligosacáridos/metabolismo , Ingeniería Metabólica , Espectrometría de MasasRESUMEN
Ferroptosis is a recently identified form of cell death characterized by iron-dependent lipid peroxidation. Understanding the effects of lipid peroxidation on cellular processes during ferroptosis requires insights into lipid droplets (LDs) and their viscosity changes. To gain further insights into the intricacies of ferroptosis, it is crucial to have a fluorescent probe that targets LDs and responds to changes in viscosity. In this study, we introduce a novel LD-targeting viscosity fluorescent probe named TQE, based on the principles of aggregation-induced emission (AIE). The probe displayed AIE characteristics in tetrahydrofuran, possessing a partition coefficient (logP) of 5.87. With increased viscosity, intramolecular rotation was restricted, leading to a remarkable 3.3-fold enhancement in emission. Notably, TQE exhibited robust resistance to photo-bleaching during cellular imaging, maintaining approximately 75% of its emission intensity even after 30 min of laser irradiation. Importantly, the AIEgen could not generate hydroxyl radicals when exposed to light for up to 3 h, suggesting the low photo-toxicity of TQE to cells. Leveraging these properties, we successfully employed the probe for fluorescent imaging of the viscosity change in LDs during ferroptosis.
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The construction of polymer-based mimicry on cell surface to manipulate cell behaviors and functions offers promising prospects in the field of biotechnology and cell therapy. However, precise control of polymer grafting sites is essential to successful implementation of biomimicry and functional modulation, which has been overlooked by most current research. Herein, we report a biological site-selected, in situ controlled radical polymerization platform for living cell surface engineering. The method utilizes metabolic labeling techniques to confine the growth sites of polymers and designs a Fenton-RAFT polymerization technique with cytocompatibility. Polymers grown at different sites (glycans, proteins, lipids) have different membrane retention time and exhibit differential effects on the recognition behaviors of cellular glycans. Of particular importance is the achievement of in situ copolymerization of glycomonomers on the outermost natural glycan sites of cell membrane, building a biomimetic glycocalyx with distinct recognition properties.
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Glicocálix , Polisacáridos , Polimerizacion , Membrana Celular , PolímerosRESUMEN
PURPOSE: Heart failure (HF) remains a major cause of late morbidity and mortality after myocardial infarction (MI). To date, no clinically established 18F-labeled sympathetic nerve PET tracers for monitoring myocardial infarction are available. Therefore, in this study, we synthesized a series of 18F-labeled benzyl guanidine analogs and evaluated their efficacy as cardiac neuronal norepinephrine transporter (NET) tracers for myocardial imaging. We also investigated the preliminary diagnostic capabilities of these tracers in myocardial infarction animal models, as well as the structure-activity relationship of these tracers. PROCEDURES: Three benzyl guanidine-NET tracers, including [18F]1, [18F]2, and [18F]3, were synthesized and evaluated in vivo as PET tracers in a myocardial infarction mouse model. [18F]LMI1195 was used as a positive control for the tracers. H&E staining of the isolated myocardial infarction heart tissue sections was performed to verify the efficacy of the selected PET tracer. RESULTS: Our data show that [18F]3 had a moderate decay corrected labeling yield (~10%) and high radiochemical purity (>95%) compared to other tracers. The uptake of [18F]3 in normal mouse hearts was 1.7±0.1%ID/cc at 1 h post-injection (p. i.), while it was 2.4±0.1, 2.6±0.9, and 2.1±0.4%ID/cc in the MI mouse hearts at 1, 2, and 3 days after surgery, respectively. Compared with [18F]LMI1195, [18F]3 had a better myocardial imaging effect in terms of the contrast between normal and MI hearts. The area of myocardial infarction shown by PET imaging corresponded well with the infarcted tissue demonstrated by H&E staining. CONCLUSIONS: With an obvious cardiac uptake contrast between normal mice and the myocardial infarction mouse model, [18F]3 appears to be a potential tool in the diagnosis of myocardial infarction. Therefore, it is necessary to conduct further structural modification studies on the chemical structure of [18F]3 to improve its in vivo stability and diagnostic detection ability to achieve reliable and practical imaging effects.
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Infarto del Miocardio , Proteínas de Transporte de Noradrenalina a través de la Membrana Plasmática , Ratones , Animales , Infarto del Miocardio/diagnóstico por imagen , Guanidinas , Tomografía de Emisión de Positrones/métodos , Modelos Animales de Enfermedad , Radioisótopos de Flúor/químicaRESUMEN
Porous hydroxyapatite (HA) scaffolds prepared by three-dimensional (3D) printing have wide application prospects owing to personalized structural design and excellent biocompatibility. However, the lack of antimicrobial properties limits its widespread use. In this study, a porous ceramic scaffold was fabricated by digital light processing (DLP) method. The multilayer chitosan/alginate composite coatings prepared by layer-by-layer method were applied to scaffolds and Zn2+ was doped into coatings in the form of ion crosslinking. The chemical composition and morphology of coatings were characterized by scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). Energy dispersive spectroscopy (EDS) analysis demonstrated that Zn2+ was uniformly distributed in the coating. Besides, the compressive strength of coated scaffolds (11.52 ± 0.3 MPa) was slightly improved compared with that of bare scaffolds (10.42 ± 0.56 MPa). The result of soaking experiment indicated that coated scaffolds exhibited delayed degradation. In vitro experiments demonstrated that within the limits of concentration, a higher Zn content in the coating has a stronger capacity to promote cell adhesion, proliferation and differentiation. Although excessive release of Zn2+ led to cytotoxicity, it presented a stronger antibacterial effect against Escherichia coli (99.4%) and Staphylococcus aureus (93%).
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Recently, laser powder bed fusion (LPBF) has shown great potential in advanced manufacturing. However, the rapid melting and re-solidification of the molten pool in LPBF leads to the distortion of parts, especially thin-walled parts. The traditional geometric compensation method, which is used to overcome this problem, is simply based on mapping compensation, with the general effect of distortion reduction. In this study, we used a genetic algorithm (GA) and backpropagation (BP) network to optimize the geometric compensation of Ti6Al4V thin-walled parts fabricated by LPBF. The GA-BP network method can generate free-form thin-walled structures with enhanced geometric freedom for compensation. For the GA-BP network training, an arc thin-walled structure was designed and printed by LBPF and measured via optical scanning measurements. The final distortion of the compensated arc thin-walled part based on GA-BP was reduced by 87.9% compared with PSO-BP and mapping method. The effectiveness of this GA-BP compensation method is further evaluated in an application case using new data points, and the result shows that the final distortion of the oral maxillary stent was reduced by 71%. In summary, the GA-BP-based geometric compensation proposed in this study can better reduce the distortion of thin-walled parts with higher time and cost efficiencies.
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Algoritmos , StentsRESUMEN
INTRODUCTION: As one of the most important and frequently used molecular imaging techniques in the clinic, positron emission tomography (PET) features high sensitivity and specificity, which generally involves the use of PET contrast agents. Despite the exceptional promise, the availability of novel PET agents could limit its application and there is a clear need to develop new PET agents to improve our understanding of targets of interest and increase the diagnostic specificity. METHODS: Based on the fact that amino acid transport and protein anabolism are increased in tumor tissues, a series of 18F-labeled amino acid analog was labeled with 18F by using [18F]fluoro-4-(vinylsulfonyl)benzene as the radionuclide linker. The obtained probes were subjected to in vitro and in vivo evaluation, including stability, cell line transport channel specificity, PET/CT imaging on tumor and inflammation bearing mice, and biodistribution. RESULTS: Our data shows that [18F]2a had moderate decay corrected labeling yield (>42 %) and high radiochemical purity (>99 %). When tested in vivo, the uptake of [18F]2a was 1.5 ± 0.2%ID/g in NCI-H1975 tumors and 1.1 ± 0.2%ID/g in inflammatory tissues. In contrast, the values for [18F]FDG were 5.7 ± 0.2%ID/g and 4.8 ± 0.1%ID/g, respectively. The inflammatory lesion-to-muscle contrast is 2.4 for [18F]2a, which is 3.0 for [18F]FDG. CONCLUSION: Clearly, [18F]2a hold the great potential for cancer imaging. Its application in distinguishing tumor from inflammatory lesion would still need to be investigated further.
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Neoplasias , Tomografía Computarizada por Tomografía de Emisión de Positrones , Ratones , Animales , Fluorodesoxiglucosa F18 , Distribución Tisular , Tomografía de Emisión de Positrones/métodos , Línea Celular Tumoral , Aminoácidos , Radioisótopos de Flúor/químicaRESUMEN
The treatment of acid wastewater to remove organic matter in acid wastewater and recycle valuable resources has great significance. However, the classical advanced oxidation process (AOPs), such as the Fenton reaction, encountered a bottleneck under the conditions of strong acid. Herein, making use of the oxidation properties of CeAY (CeO2@acid clay), we built an AOPs reaction system without H2O2 under a strong acid condition that can realize the transformation of organic matter in industrial wastewater. The X-ray photoelectron spectroscopy (XPS) proved that the CeAY based on Ce3+ as an active center has abundant oxygen vacancies, which can catalyze O2 to produce reactive oxygen species (ROS). Based on the electron spin-resonance spectroscopy spectrum and radical trapping experiments, the production of â¢O2- and â¢OH can be determined, which are the essential factors of the degradation of organic compounds. In the system of pH = 1.0, when 1 mg CeAY is added to 10 mL of wastewater, the degradation efficiency of an aniline solution with a 5 mg/L effluent concentration is 100%, and that of a benzoic acid solution with a 100 mg/L effluent concentration is 50% after 10 min of reaction. This work may provide novel insights into the removal of organic pollutants in a strong acid water matrix.
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BACKGROUND: Fumonisin B1 (FB1) is a secondary metabolite produced mainly by Fusarium verticillioides or Fusarium proliferatum. It poses a huge threat to the sustainable animal industry and human health as well via food chains (egg, meat and milk). Although E. coli-expressed nanobodies are documented for diagnostic applications, nanobodies remain elusive as FB1 detoxifiers in feed and food. RESULTS: In the present study, the E. coli-expressed nanobody was assessed to remove FB1 in fresh milk, embryonated eggs and broilers. Firstly, 2 alpacas received intramuscularly FB1-adjuvanted BSA 6 times, and then the variable domain of the heavy-chain antibody (VHH) of fb1 genes were amplified to clone into the pCANTAB 5 E vector in order to generate a VHH-FB1 phage antibody display library, yielding 3.4 × 1010 capacity with 96.7% positivity. Afterwards, 5 anti-FB1 nanobodies were expressed and identified. Furthermore, maximal 43.2% FB1 was removed from milk by 1:2000 concentration of nanobody 5 (Nb5). Furthermore, SPF-embryonated eggs were inoculated into albumens with nanobody-treated FB1. The Nb5 group yielded an 83.3% hatching rate, higher body weight, lower gizzard ulceration and fewer FB1 residuals. In order to warrant the above results, 50 broilers aged 10 days were received orally with 20 ppm of FB1 for 20 days. At the same time, birds were fed orally with 50 µg of Nb5 or bivalent nanobody 11 (BiNb11). Finally, the Nb5 group showed a higher relative body weight gain and lower gastric ulcerations and fewer inflammations in the thymus and bursa. CONCLUSIONS: Based on the above evidence, the Nb5 nanobody may be considered as an additional FB1 detoxifier, contributing to FB1 decontamination.