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1.
Front Neurosci ; 18: 1401329, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38948927

RESUMEN

Introduction: Brain medical image segmentation is a critical task in medical image processing, playing a significant role in the prediction and diagnosis of diseases such as stroke, Alzheimer's disease, and brain tumors. However, substantial distribution discrepancies among datasets from different sources arise due to the large inter-site discrepancy among different scanners, imaging protocols, and populations. This leads to cross-domain problems in practical applications. In recent years, numerous studies have been conducted to address the cross-domain problem in brain image segmentation. Methods: This review adheres to the standards of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) for data processing and analysis. We retrieved relevant papers from PubMed, Web of Science, and IEEE databases from January 2018 to December 2023, extracting information about the medical domain, imaging modalities, methods for addressing cross-domain issues, experimental designs, and datasets from the selected papers. Moreover, we compared the performance of methods in stroke lesion segmentation, white matter segmentation and brain tumor segmentation. Results: A total of 71 studies were included and analyzed in this review. The methods for tackling the cross-domain problem include Transfer Learning, Normalization, Unsupervised Learning, Transformer models, and Convolutional Neural Networks (CNNs). On the ATLAS dataset, domain-adaptive methods showed an overall improvement of ~3 percent in stroke lesion segmentation tasks compared to non-adaptive methods. However, given the diversity of datasets and experimental methodologies in current studies based on the methods for white matter segmentation tasks in MICCAI 2017 and those for brain tumor segmentation tasks in BraTS, it is challenging to intuitively compare the strengths and weaknesses of these methods. Conclusion: Although various techniques have been applied to address the cross-domain problem in brain image segmentation, there is currently a lack of unified dataset collections and experimental standards. For instance, many studies are still based on n-fold cross-validation, while methods directly based on cross-validation across sites or datasets are relatively scarce. Furthermore, due to the diverse types of medical images in the field of brain segmentation, it is not straightforward to make simple and intuitive comparisons of performance. These challenges need to be addressed in future research.

2.
Front Psychol ; 15: 1382143, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38966742

RESUMEN

Virtual urban green environment images and audio stimuli had been proven to have restorative effects on subjects' physical and mental health. In this area, researchers predominantly focused on visual, auditory and olfactory aspects, while tactile and gustatory senses have been minimally explored. However, the optimal combination of sensory stimuli for promoting physical and mental recovery remains unclear. Therefore, a simulated sensory stimulation approach involving 240 participants was employed, with 30 individuals included in each of the eight experimental groups: the visual-auditory (VA), visual-auditory-olfactory (VAO), visual-auditory-tactile (VAT), visual-auditory-gustatory(VAG), visual-auditory-olfactory-tactile (VAOT), visual-auditory-olfactory-gustatory (VAOG), visual-auditory-tactile-gustatory (VATG), and visual-auditory-olfactory-tactile-gustatory (VAOTG) groups. This study aimed to explore the differences in participants' physiological and psychological health recovery after exposure to different combinations of simulated sensory stimuli in virtual UGSs. The results indicated that the following: (1) In terms of physiological recovery, the blood pressure of the 8 experimental groups decreased significantly after the experiment, indicating that the virtual urban green space environment has a certain recovery effect on physiological state. The combination of VAOTG stimuli in the multisensory group resulted in the best blood pressure recovery (p < 0.05). Tactile is an important sense to enhance the physiological recovery effect. Olfactory-tactile or tactile-gustatory stimuli interactions significantly enhance physiological recovery, emphasizing the importance of tactile stimulation in improving physiological recovery. (2) In terms of psychological recovery, the common trigger of olfactory-gustatory is the most key element to enhance psychological recovery through multi-sensory stimulation of virtual urban green space environment. VAOG stimulation had the best effect on psychological recovery (p < 0.05), followed by VAOTG stimulation (p < 0.05). Gustatory is an important sense to enhance the psychological recovery effect, and both the tactile-gustatory interaction and the olfactory-gustatory interaction significantly enhance the recovery effect. At the same time, the psychological recovery effect obtained by four or more sensory combinations was higher than that obtained by two or three sensory stimulation groups. This study confirms more possibilities for ways to restore physical and mental health through virtual natural environments. It expands the research on the benefits of virtual nature experience and provides theoretical support for the application of this method.

3.
Quant Imaging Med Surg ; 14(7): 4950-4964, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39022246

RESUMEN

Background: Accurate efficacy evaluation of bone metastases (BMs) from breast cancer (BC) is an intractable issue in clinical practice, for which solutions are urgently needed. This study aimed to investigate the utility of 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG PET/CT) in the response evaluation of bone metastasis of BC. Methods: In total, 22 patients diagnosed with BC and BM were enrolled. These patients underwent repeated 18F-FDG PET/CT evaluations. The patients and each BM site were divided into two groups based on their response to treatment: progressive disease (PD) and nonprogressive disease (non-PD). We analyzed and compared the changes in PET and CT images, as well as the serum concentration of carcinoembryonic antigen (CEA), carbohydrate antigen 153 (CA153), alkaline phosphatase (ALP), and calcium (Ca) over the same time frame. The immunohistochemistry (IHC) of primary lesions between groups and between the primary focus and BM with high 18F-FDG uptake were compared and analyzed. Results: Maximum standard uptake value (SUVmax) after therapy [area under the curve (AUC): 0.932] and Δ-value of SUVmax (AUC: 0.811) on 18F-FDG PET imaging proved significantly valuable for the efficacy of therapy outcomes related to BM lesions (P<0.05). In terms of overall evaluation of BM, age and human epidermal growth factor receptor 2 (HER2) expression were significantly lower in the PD group than in the non-PD group (P<0.05). There were marked differences in CEA after therapy, the changes of CEA, and CA153 (∆-value) between the groups (P<0.05). The SUVmax and Ca concentration after therapy and ∆-value of SUVmax, along with the levels of CA153, CEA, and ALP, were valuable indicators for evaluating the efficacy of individual BMs (P<0.05). IHC of BM in the PD group showed differences compared to primary lesions, with antigen Ki-67 being downregulated in metastatic lesions and HER2 being downregulated in a portion of BMs (2 of 6). Meanwhile, the expression of estrogen receptor (ER) and progesterone receptor (PR) remained relatively unchanged. Conclusions: 18F-FDG PET/CT confers precise assessment of the posttreatment efficacy pertaining to BM in BC. This modality facilitates the identification of poor effect lesions following extant therapies and localization for pathological assessment and may substantially contribute to evaluating therapeutic efficacy, refining treatment strategies, and predicting the disease trajectory of patients with BC and BM.

4.
Small ; : e2402761, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38953299

RESUMEN

Flexible rechargeable Zn-air batteries (FZABs) exhibit high energy density, ultra-thin, lightweight, green, and safe features, and are considered as one of the ideal power sources for flexible wearable electronics. However, the slow and high overpotential oxygen reaction at the air cathode has become one of the key factors restricting the development of FZABs. The improvement of activity and stability of bifunctional catalysts has become a top priority. At the same time, FZABs should maintain the battery performance under different bending and twisting conditions, and the design of the overall structure of FZABs is also important. Based on the understanding of the three typical configurations and working principles of FZABs, this work highlights two common strategies for applying bifunctional catalysts to FZABs: 1) powder-based flexible air cathode and 2) flexible self-supported air cathode. It summarizes the recent advances in bifunctional oxygen electrocatalysts and explores the various types of catalyst structures as well as the related mechanistic understanding. Based on the latest catalyst research advances, this paper introduces and discusses various structure modulation strategies and expects to guide the synthesis and preparation of efficient bifunctional catalysts. Finally, the current status and challenges of bifunctional catalyst research in FZABs are summarized.

5.
J Colloid Interface Sci ; 674: 852-861, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38955016

RESUMEN

Lithium-selenium (Li-Se) batteries are considered promising alternatives to lithium-ion batteries due to their higher volumetric capacity and energy density. However, they still face limitations in efficiently utilizing the active selenium. Here, we develop surface-functionalized mesoporous hollow carbon nanospheres as the selenium host. By using KOH activation, the surface of the carbon nanospheres is functionalized with hydroxyl groups, which greatly improve the utilization of selenium and facilitate the conversion of lithium selenides, leading to much higher capacities compared to ZnCl2 activation and untreated carbon nanospheres. Theory and experimental evidence suggest that surface hydroxyl groups can enhance the reduction conversion of polyselenides to selenides and facilitate the oxidation reaction of selenides to elemental selenium. In-situ and ex-situ characterization techniques provided additional confirmation of the hydroxyl groups electrochemical durability in catalyzing selenium conversion. The meticulously engineered Se cathode demonstrates a high specific capacity of 594 mA h g-1 at 0.5C, excellent rate capability of 464 mA h g-1 at 2C, and a stable cycling performance of 500 cycles at 2C with a capacity retention of 84.8 %, corresponding to an ultra-low-capacity decay rate of 0.0144 % per cycle, surpassing many reported lithium-selenium battery technologies.

6.
Artículo en Inglés | MEDLINE | ID: mdl-39019667

RESUMEN

BACKGROUND: The rate of distant metastasis in patients with pancreatic neuroendocrine tumors (PNETs) is 20%-50% at the time of initial diagnosis. However, whether tumor size can predict distant metastasis for PNETs remains unknown up to date. METHODS: We used Surveillance, Epidemiology, and End Results (SEER) population-based data to collect 6089 patients with PNETs from 2010 to 2019. The optimal cut-off point of tumor size to predict distant metastasis was calculated by Youden's index. Multivariate logistic regression analysis was used to figure out the association between tumor size and distant metastasis patterns. RESULTS: The most common metastatic site was liver (27.2%), followed by bone (3.0%), lung (2.3%) and brain (0.4%). Based on an optimal cut-off value of tumor size (25.5 mm) for predicting distant metastasis determined by Youden's index, patients were categorized into groups of tumor size < 25.5 mm and ≥ 25.5 mm. Multivariate logistic regression analyses showed that, compared with < 25.5 mm, tumor size ≥ 25.5 mm was an independent risk predictor of overall distant metastasis [odds ratio (OR) = 4.491, 95% confidence interval (CI): 3.724-5.416, P < 0.001] and liver metastasis (OR = 4.686, 95% CI: 3.886-5.651, P < 0.001). CONCLUSIONS: Tumor size ≥ 25.5 mm was significantly associated with more overall distant and liver metastases. Timely identification of distant metastasis for tumor size ≥ 25.5 mm may provide survival benefit for timely and precise treatment.

7.
Medicine (Baltimore) ; 103(27): e38803, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38968476

RESUMEN

The objective of this study was to assess the clinical effectiveness and safety of type A botulinum toxin in the treatment of refractory overactive bladder in adolescents. We conducted a retrospective analysis of 37 adolescent patients with refractory overactive bladder who were treated at the Urology Department of Hangzhou Third People's Hospital between January 2018 and August 2023. These patients received intravesical injections of type A botulinum toxin at a concentration of 10 U/mL, with an average of 20 injection points. We recorded changes in urination diaries and urodynamic parameters both before and 1 month after treatment. After 1 month of treatment, significant improvements were observed in several parameters, when compared to the pretreatment values. These included daytime frequency of urination (11.13 ±â€…6.45), average single void volume (173.24 ±â€…36.48) mL, nighttime frequency of urination (2.43 ±â€…0.31), urgency episodes (3.12 ±â€…0.27), initial bladder capacity (149.82 ±â€…41.34) mL, and maximum bladder capacity (340.25 ±â€…57.12) mL (all P < .001). After the first treatment, 5 patients had mild hematuria, 4 patients had urinary tract infection, and 1 patient had urinary retention, which was relieved after catheterization. No serious complications or adverse reactions were observed in other patients. The follow-up period ranged from 6 to 18 months, and the duration of efficacy varied from 2 to 8 months. Eight patients who initially had treatment failure achieved symptom relief after reinjection. In adolescents with refractory overactive bladder who do not respond well to conventional drug therapy, type A botulinum toxin can be administered safely and effectively. It significantly improves lower urinary tract symptoms and enhances the quality of life for these patients.


Asunto(s)
Toxinas Botulínicas Tipo A , Vejiga Urinaria Hiperactiva , Humanos , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Toxinas Botulínicas Tipo A/uso terapéutico , Toxinas Botulínicas Tipo A/administración & dosificación , Toxinas Botulínicas Tipo A/efectos adversos , Adolescente , Femenino , Estudios Retrospectivos , Masculino , Resultado del Tratamiento , Administración Intravesical , Fármacos Neuromusculares/administración & dosificación , Fármacos Neuromusculares/uso terapéutico , Fármacos Neuromusculares/efectos adversos , Urodinámica/efectos de los fármacos
8.
Nat Commun ; 15(1): 5761, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38982055

RESUMEN

While protein aggregation's association with aging and age-related diseases is well-established, the specific proteins involved and whether dissolving them could alleviate aging remain unclear. Our research addresses this gap by uncovering the role of PKM2 aggregates in aging. We find that PKM2 forms aggregates in senescent cells and organs from aged mice, impairing its enzymatic activity and glycolytic flux, thereby driving cells into senescence. Through a rigorous two-step small molecule library screening, we identify two compounds, K35 and its analog K27, capable of dissolving PKM2 aggregates and alleviating senescence. Further experiments show that treatment with K35 and K27 not only alleviate aging-associated signatures but also extend the lifespan of naturally and prematurely aged mice. These findings provide compelling evidence for the involvement of PKM2 aggregates in inducing cellular senescence and aging phenotypes, and suggest that targeting these aggregates could be a promising strategy for anti-aging drug discovery.


Asunto(s)
Envejecimiento , Senescencia Celular , Proteínas de Unión a Hormona Tiroide , Animales , Envejecimiento/metabolismo , Ratones , Humanos , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Proteínas Portadoras/metabolismo , Glucólisis , Hormonas Tiroideas/metabolismo , Agregado de Proteínas , Piruvato Quinasa/metabolismo , Ratones Endogámicos C57BL , Masculino
9.
Anal Biochem ; 694: 115603, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38986796

RESUMEN

The recognition of DNA-binding proteins (DBPs) is the crucial step to understanding their roles in various biological processes such as genetic regulation, gene expression, cell cycle control, DNA repair, and replication within cells. However, conventional experimental methods for identifying DBPs are usually time-consuming and expensive. Therefore, there is an urgent need to develop rapid and efficient computational methods for the prediction of DBPs. In this study, we proposed a novel predictor named PreDBP-PLMs to further improve the identification accuracy of DBPs by fusing the pre-trained protein language model (PLM) ProtT5 embedding with evolutionary features as input to the classic convolutional neural network (CNN) model. Firstly, the ProtT5 embedding was combined with different evolutionary features derived from the position-specific scoring matrix (PSSM) to represent protein sequences. Then, the optimal feature combination was selected and input to the CNN classifier for the prediction of DBPs. Finally, the 5-fold cross-validation (CV), the leave-one-out CV (LOOCV), and the independent set test were adopted to examine the performance of PreDBP-PLMs on the benchmark datasets. Compared to the existing state-of-the-art predictors, PreDBP-PLMs exhibits an accuracy improvement of 0.5 % and 5.2 % on the PDB186 and PDB2272 datasets, respectively. It demonstrated that the proposed method could serve as a useful tool for the recognition of DBPs.

10.
ACS Appl Mater Interfaces ; 16(24): 31756-31767, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38837185

RESUMEN

High-performance thin films combining large optical bandgap Al2O3 and high refractive index HfO2 are excellent components for constructing the next generation of laser systems with enhanced output power. However, the growth of low-defect plasma-enhanced-atomic-layer-deposited (PEALD) Al2O3 for high-power laser applications and its combination with HfO2 and SiO2 materials commonly used in high-power laser thin films still face challenges, such as how to minimize defects, especially interface defects. In this work, substrate-layer interface defects in Al2O3 single-layer thin films, layer-layer interface defects in Al2O3-based bilayer and trilayer thin films, and their effects on the laser-induced damage threshold (LIDT) were investigated via capacitance-voltage (C-V) measurements. The experimental results show that by optimizing the deposition parameters, specifically the deposition temperature, precursor exposure time, and plasma oxygen exposure time, Al2O3 thin films with low defect density and high LIDT can be obtained. Two trilayer anti-reflection (AR) thin film structures, Al2O3/HfO2/SiO2 and HfO2/Al2O3/SiO2, were then prepared and compared. The trilayer AR thin film with Al2O3/HfO2/SiO2 structure exhibits a lower interface defect density, better interface bonding performance, and an increase in LIDT by approximately 2.8 times. We believe these results provide guidance for the control of interface defects and the design of thin film structures and will benefit many thin film optics for laser applications.

11.
Eur Spine J ; 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38869649

RESUMEN

PURPOSE: To evaluate different patterns of coronal deformity secondary to ankylosing spondylitis (AS), to propose relevant treatment strategies, and to assess efficacy of asymmetrical pedicle subtraction osteotomy (APSO). METHODS: Coronal deformity was defined as coronal Cobb angle over 20º or coronal balance distance (CBD) more than 3 cm. 65 consecutive AS patients with concomitant coronal and sagittal deformity who underwent PSO were included. The average follow-up time was 40.4 months. Radiographic evaluation included coronal Cobb angle and CBD. Furthermore, sagittal parameters were used to assess magnitude and maintenance of kyphosis correction. RESULTS: Based on curve characteristics, coronal deformity caused by AS included four different radiologic patterns: Pattern I: lumbar scoliosis; Pattern II: C-shaped thoracolumbar curve; Pattern III: trunk shift without major curve; Pattern IV: proximal thoracic scoliosis. APSO was performed for patients in Pattern I to III while conventional PSO was applied for patients in Pattern IV. Significant improvement in all the sagittal parameters were noted in 65 patients without obvious correction loss at the last follow-up. Besides, significant and sustained correction of coronal mal-alignment was identified in 59 APSO-treated patients. Rod fracture occurred in four cases and revision surgery was performed for one case. CONCLUSION: According to radiologic manifestations, coronal deformity caused by AS could be categorized into four patterns. APSO proved to be a feasible and effective procedure for correction of Pattern I to III patients. Coronal deformity pattern, apex location, sagittal profile of lumbar spine and preoperative hip function should be considered for osteotomy level selection in APSO.

12.
Environ Technol ; : 1-9, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38920111

RESUMEN

Phosphorus (P) recovery from sewage sludge ash (SSA) is considered to be an effective method for P recovery. In this work, P extraction and the removal of heavy metals were realized by electrodialysis. Low-cost, easily available, and environmentally friendly plant extracts were applied as suspension to reduce the inevitable secondary pollution. And the feasibility of using plant extracts was analysed by comparing with using deionized water (DI) and oxalic acid (OA) solution. When SSA was suspended in different solutions (DI, OA, and three plant extracts - Hovenia acerba (HA), Saponin (SA) and Portulaca oleracea (PO)), the effects of reaction time and plant extract concentration on P extraction and heavy metal separation of SSA under ED treatment were compared. After the process of electrodialysis, compared to other experimental groups, electrodialysis with plant extracts obtained more P released from SSA, but less P migrated to the anode chamber. However, when SSA was suspended in PO at a concentration of 80 g/L, the proportion of P transferred from SSA to the anode chamber can still reached 37.86%. In addition, the use of plant extracts as suspension had a positive effect on the removal of heavy metals, but its effect was lower than that of the oxalic acid-treated experimental group. The results indicated that the use of plant extracts for wet-chemical extraction combined with electrodialysis promoted the removal of heavy metals and the extraction of P from SSA, which is a feasible option.

13.
Chemistry ; : e202400668, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38822692

RESUMEN

Quinazoline (Qz)-linked covalent organic frameworks (COFs) have been constructed via a three-component reaction of ortho-acylanilines, benzaldehydes and NH4OAc. The structure of Qz-COFs has been confirmed by solid-state nuclear magnetic resonance spectroscopy, Fourier transform infrared and powder X-ray diffraction patterns. The Qz-COFs possess high chemical stability, showing good endurance to strong acid, strong base, oxidant, reductant and other conditions. Particularly, Qz-COF-3 can catalyze the aerobic photooxidation of toluene and other compounds containing C(sp3)-H bonds.

15.
Front Pediatr ; 12: 1400124, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38813545

RESUMEN

Background: Bronchopulmonary foregut malformation (BPFM) is an uncommon condition, with few case reports documented in both national and international literature. This scarcity underscores the importance of utilizing effective imaging techniques to improve our understanding and diagnostic precision concerning this disorder. Case description: In the first case report, a neonate, born at full term and aged 15 days, presented with symptoms including dyspnea, coughing, wheezing, cyanosis, and vomiting. Initial diagnostic evaluations, which included chest radiography and upper gastrointestinal tract radiography, led to an erroneous initial diagnosis of a left-sided diaphragmatic hernia, accompanied by a suspicion of infection. In the second case report, another neonate, also born at full term but aged 5 days, exhibited symptoms such as coughing, choking, and mild vomiting. Utilizing a combination of computed tomography (CT) scans (plain, enhanced, and reconstructed), chest x-ray, and upper gastrointestinal tract radiography, the diagnosis of BPFM was accurately determined. Conclusion: Comprehensive imaging examinations play a crucial role in reducing misdiagnosis and diagnostic oversights in cases of BPFM. Given its rarity, BPFM often manifests as a sequestered lung accompanied by gastrointestinal abnormalities. Hence, the integration of CT scans with gastrointestinal tract radiography can substantially improve diagnostic precision in such cases.

17.
Oncol Lett ; 28(1): 314, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38807664

RESUMEN

There has been rapid advancement in the development of neoadjuvant therapy for non-small cell lung cancer (NSCLC), which holds great promise as an effective treatment strategy. Some clinical trials have confirmed that immunotherapy in combination with chemotherapy can be a recommended first-line regimen for neoadjuvant treatment of NSCLC. The present study describes the case of a male patient aged 65 years who was diagnosed with stage IIIA (cT2N2M0) adenosquamous carcinoma of the lung. After the administration of two cycles of neoadjuvant immunotherapy (sintilimab) in combination with chemotherapy, stable disease was observed in the primary tumor, whereas partial remission was detected in the mediastinal lymph nodes based on imaging assessment. The patient underwent an immediate upper lobectomy of the left lung. Pathological analysis revealed a complete response in the primary lesion, with only minimal presence of tumor cells observed in the lymph nodes surrounding the mediastinum and bronchi. This indicated that the present neoadjuvant therapy could be used in the treatment of stage III adenosquamous lung carcinoma; however, to conclusively determine its efficacy, further studies targeting this specific cancer type are essential.

18.
Nanotechnology ; 35(31)2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38764182

RESUMEN

Semiconductor devices at the nanoscale with low-dimensional materials as channels exhibit quantum transport characteristics, thereby their electrical simulation relies on the self-consistent solution of the Schrödinger-Poisson equations. While the non-equilibrium Green's function (NEGF) method is widely used for solving this quantum many-body problem, its high computational cost and convergence challenges with the Poisson equation significantly limit its applicability. In this study, we investigate the stability of the NEGF method coupled with various forms of the Poisson equation, encompassing linear, analytical nonlinear, and numerical nonlinear forms Our focus lies on simulating carbon nanotube field-effect transistors (CNTFETs) under two distinct doping scenarios: electrostatic doping and ion implantation doping. The numerical experiments reveal that nonlinear formulas outperform linear counterpart. The numerical one demonstrates superior stability, particularly evident under high bias and ion implantation doping conditions. Additionally, we investigate different approaches for presolving potential, leveraging solutions from the Laplace equation and a piecewise guessing method tailored to each doping mode. These methods effectively reduce the number of iterations required for convergence.

19.
Int J Biol Macromol ; 269(Pt 1): 132072, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38705339

RESUMEN

Chitosan (CTS) and chitosan oligosaccharides (COS) have been widely applied in food industry due to their bioactivities and functions. However, CTS and COS with positive charges could interact with proteins, such as whey protein isolate (WPI), influencing their digestion. Interaction among CTS/COS, FUC, and WPI/enzymes was studied by spectroscopy, chromatography, and chemical methods in order to reveal the role of FUC in relieving the inhibition of protein digestibility by CTS/COS and demonstrate the action mechanisms. As shown by the results, the addition of FUC increased degree of hydrolysis (DH) and free protein in the mixture of CTS and WPI to 3.1-fold and 1.8-fold, respectively, while raise DH value and free protein in the mixture of COS and WPI to 6.7-fold and 1.2-fold, respectively. The interaction between amino, carboxyl, sulfate, and hydroxyl groups from carbohydrates and protein could be observed, and notably, FUC could interact with CTS/COS preferentially to prevent CTS/COS from combining with WPI. In addition, the addition of FUC could also relieve the combination of CTS to trypsin, increasing the fluorescence intensity and concentration of trypsin by 83.3 % and 4.8 %, respectively. Thus, the present study demonstrated that FUC could alleviate the inhibitory effect of CTS/COS on protein digestion.


Asunto(s)
Quitosano , Oligosacáridos , Polisacáridos , Quitosano/química , Quitosano/farmacología , Oligosacáridos/farmacología , Oligosacáridos/química , Polisacáridos/farmacología , Polisacáridos/química , Polisacáridos/metabolismo , Hidrólisis , Proteína de Suero de Leche/química , Proteína de Suero de Leche/farmacología , Proteína de Suero de Leche/metabolismo , Tripsina/metabolismo , Tripsina/química , Proteolisis/efectos de los fármacos
20.
Anal Chem ; 96(19): 7367-7372, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38696818

RESUMEN

Immunogold, that is, gold nanoparticles (AuNPs) conjugated with biomolecules such as antibodies and peptides, have been widely used to construct sandwiched immunosensors for biodetection. Two main challenges in these immunoassays are difficulties in finding and validating a suitable antibody, and the nonspecific interaction between the substrate and immunogold, which lowers the detection sensitivity and even causes false results. To avoid these issues, we took advantage of the nonspecific interaction between AuNPs and capture antibodies and proposed a new sensing mechanism. That is, after the capture of analyte targets by the capture antibodies on the substrate, AuNPs of certain chemical functionality would preferably bind to the free capture antibodies. Consequently, the amount of deposited AuNPs will inversely depend on the concentration of the analytes. As a proof-of-concept, we designed a mass-based sensor where anti-IgG antibodies were coated on a quartz crystal microbalance substrate. After IgG was introduced, tannic acid-capped AuNPs were applied to bind with the free anti-IgG antibody molecules. A frequency change (Δf) of the quartz substrate was induced by the increased mass loading. To further amplify the loading mass, an Ag enhancer solution was added, and Ag growth was catalyzed by the bound AuNPs. The Δf response showed a concentration-dependent decrease when increasing IgG concentration with a detection limit of 2.6 ng/mL. This method relies on the nonspecific interaction between AuNPs and anti-IgG antibodies to realize sensitive detection of IgG and eliminates the use of detection antibodies. The concept is an alternative to many existing immunoassay technologies.


Asunto(s)
Técnicas Biosensibles , Oro , Nanopartículas del Metal , Oro/química , Nanopartículas del Metal/química , Inmunoensayo/métodos , Técnicas Biosensibles/métodos , Inmunoglobulina G/inmunología , Inmunoglobulina G/análisis , Tecnicas de Microbalanza del Cristal de Cuarzo
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