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A trypsin affinity material was prepared by covalently immobilizing buckwheat trypsin inhibitor (BTI) on epichlorohydrin-activated cross-linked agarose gel (Selfinose CL 6 B). The optimal conditions for activating Selfinose CL 6 B were 15 % epichlorohydrin and 0.8 M NaOH at 40 °C for 2 h. The optimal pH for immobilizing BTI was 9.5. BTI-Sefinose CL 6 B showed a maximum adsorption capacity of 2.25 mg trypsin/(g support). The material also displayed good reusability, retaining over 90 % of its initial adsorption capacity after 30 cycles. High-purity trypsin was obtained from locust homogenate using BTI-Selfinose CL 6 B through one-step affinity chromatography. The molecular mass and Km value of locust trypsin were determined as 27 kDa and 0.241 mM using N-benzoyl-DL-arginine-nitroanilide as substrate. The optimal temperature and pH of trypsin activity were 55 °C and 9.0, respectively. The enzyme exhibited good stability in the temperature range of 30-50 °C and pH range of 4.0-10.0. BTI-Selfinose CL 6 B demonstrates potential application in the preparation of high-purity trypsin and the discovery of more novel trypsin from various species.
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Cromatografia de Afinidade , Proteínas Recombinantes , Inibidores da Tripsina , Tripsina , Tripsina/química , Tripsina/metabolismo , Inibidores da Tripsina/química , Inibidores da Tripsina/isolamento & purificação , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Cromatografia de Afinidade/métodos , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/química , Concentração de Íons de Hidrogênio , Fagopyrum/química , Temperatura , Sefarose/química , Estabilidade EnzimáticaRESUMO
Dopamine (DA) neurons play a crucial role in the development and manifestation of depression, as well as in response to antidepressant treatments. While the function of the predominantly distributed DA neurons in the ventral tegmental area (VTA) is well established, the contribution of a small fraction of DA neurons in the dorsal raphe nucleus (DRN) during depression remains unclear. In this study, we found that chronic unpredictable stress (CUS) induces depression-related behaviors and decreases spontaneous firing rates, excitatory and inhibitory postsynaptic currents of DA neurons in the DRN associated with reduced excitatory synaptic transmission in male and female mice. The chemogenetic inhibition of DA neurons in the DRN produces depressive phenotypes. Conversely, their activation completely reversed the anhedonic and despair behaviors induced by CUS. Furthermore, we showed that a DRN dopaminergic projecting to the dorsal bed nucleus of the stria terminalis (dBNST) selectively controls depressive behaviors by influencing the neural activity and N-methyl-D-aspartate receptor (NMDAR) mediating EPSC of calcium/calmodulin-dependent protein kinase II+ (CaMKII+) target neurons by regulating dopamine neurotransmitter and dopamine receptor 2 (DR2) in the dBNST. Overall, these findings highlight the essential role of the DRNDA â dBNSTCaMKII+ neural circuit in bi-directionally mediating stress-induced depression-related behaviors. Our findings indicate that DRN DA neurons are a key component of the neural circuitry involved in regulating depression-related behaviors, making them a potential therapeutic target for depression.
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Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Depressão , Neurônios Dopaminérgicos , Núcleo Dorsal da Rafe , Núcleos Septais , Animais , Neurônios Dopaminérgicos/metabolismo , Núcleo Dorsal da Rafe/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Camundongos , Núcleos Septais/metabolismo , Núcleos Septais/fisiopatologia , Masculino , Feminino , Depressão/metabolismo , Depressão/fisiopatologia , Estresse Psicológico/metabolismo , Estresse Psicológico/fisiopatologia , Camundongos Endogâmicos C57BL , Comportamento Animal , Modelos Animais de Doenças , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores de Dopamina D2/metabolismo , Potenciais Pós-Sinápticos Excitadores/fisiologia , Transmissão Sináptica/fisiologiaRESUMO
Adipocyte enhancer-binding protein 1 (AEBP1) is closely implicated in osteoblastic differentiation and bone fracture; this research aimed to investigate the effect of AEBP1 on restoring osteoblastic differentiation under dexamethasone (Dex) treatment, and its interaction with the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway. Pre-osteoblastic MC3T3-E1 cells were cultured in osteogenic medium and treated by Dex to mimic steroid-induced osteonecrosis cellular model. They were then further transfected with control or AEBP1-overexpressed lentiviral vectors. Finally, cells were treated with the PI3K inhibitor LY294002, with or without AEBP1-overexpressed lentiviral vectors. AEBP1 expression showed a downward trend in MC3T3-E1 cells under Dex treatment in a dose-dependent manner. AEBP1-overexpressed lentiviral vectors increased relative cell viability, alkaline phosphatase (ALP) staining, Alizarin red staining and osteoblastic differentiation markers including osteocalcin (OCN), osteopontin (OPN), collagen type I alpha 1 (COL1A1), runt-related transcription factor 2 (RUNX2) and bone morphogenetic protein 2 (BMP2), but decreased cell apoptosis rate in MC3T3-E1 cells under Dex treatment; besides, AEBP1-overexpressed lentiviral vectors positively regulated p-PI3K and p-AKT expressions. Furthermore, LY294002 treatment decreased relative cell viability, Alizarin red staining, osteoblastic differentiation markers including OCN, OPN, RUNX2 and BMP, increased cell apoptosis rate and did not affect ALP staining in MC3T3-E1 cells under Dex treatment; meanwhile, LY294002 treatment weakened the effect of AEBP1 overexpression vectors on the above cell functions. AEBP1 restores osteoblastic differentiation under Dex treatment by activating the PI3K/AKT pathway.
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Diferenciação Celular , Dexametasona , Osteoblastos , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Osteoblastos/efeitos dos fármacos , Osteoblastos/citologia , Osteoblastos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Diferenciação Celular/efeitos dos fármacos , Camundongos , Animais , Dexametasona/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular , Osteogênese/efeitos dos fármacos , Apoptose/efeitos dos fármacosRESUMO
BACKGROUND AND AIMS: Cardiac glycosides (CGs), traditionally used for heart failure, have shown potential as anti-cancer agents. This study aims to explore their multifaceted mechanisms in cancer cell biology using proteome integral solubility alteration (PISA), focusing on the interaction with key proteins implicated in cellular metabolism and mitochondrial function. METHODS: We conducted lysate-based and intact-cell PISA assays on cancer cells treated with CGs (Digoxin, Digitoxin, Ouabain) to analyze protein solubility changes. This was followed by mass spectrometric analysis and bioinformatics to identify differentially soluble proteins (DSPs). Molecular docking simulations were performed to predict protein-CG interactions. Public data including gene expression changes upon CG treatment were re-analyzed for validation. RESULTS: The PISA assays revealed CGs' broad-spectrum interactions, particularly affecting proteins like PKM2, ANXA2, SLC16A1, GOT2 and GLUD1. Molecular docking confirmed stable interactions between CGs and these DSPs. Re-analysis of public data supported the impact of CGs on cancer metabolism and cell signaling pathways. CONCLUSION: Our findings suggest that CGs could be repurposed for cancer therapy by modulating cellular processes. The PISA data provide insights into the polypharmacological effects of CGs, warranting further exploration of their mechanisms and clinical potential.
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Glicosídeos Cardíacos , Simulação de Acoplamento Molecular , Proteoma , Solubilidade , Humanos , Glicosídeos Cardíacos/farmacologia , Glicosídeos Cardíacos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Biologia Computacional/métodosRESUMO
Tumour immunotherapy represented by immune checkpoint inhibitors (ICIs) has greatly improved the overall prognosis of patients with malignant tumours, and is regarded as an important breakthrough in the field of medicine in recent years. ICIs have gradually become the core of tumour therapy and are increasingly used in the clinic. In order to achieve early clinical prediction and management of immune-related adverse events (irAEs), it is still necessary to perform further research on the mechanisms, risk factors, and predictors of irAE occurrence in the future. Zhou et al describe the consultation of a patient with advanced gastric cancer combined with chronic plaque psoriasis. This case provides an important reference for the use of programmed cell death protein-1 (PD-1) inhibitors in patients of tumours combined with chronic plaque psoriasis. This case also highlights that screening of high-risk groups for irAEs is critical before applying PD-1 inhibitors to patients with chronic psoriasis combined with tumours. PD-1 inhibitors are new and potent antineoplastic agents that can cause serious immune-related adverse events such as toxic epidermal necrolysis release and psoriasis. Glucocorticosteroids are the first-line agents for irAEs. The incidence of rheumatic irAEs may be higher in reality, which will inevitably become a new challenge for rheumatologists and dermatologists.
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BACKGROUND AND OBJECTIVE: This study focuses on investigating the role of CDKN1A in cisplatin-induced AKI ( acute kidney injury, AKI) and its potential as a biomarker for early diagnosis and therapeutic intervention by integrating bioinformatics analysis, machine learning, and experimental validation. METHODS: We analyzed the GSE85957 dataset to find genes that changed between control and cisplatin-treated rats. Using bioinformatics and machine learning, we found 13 important genes related to ferroptosis and the P53 pathway. The key gene, CDKN1A, was identified using various algorithms. We then tested how reducing CDKN1A in human kidney cells affected cell health, ROS, and iron levels. We also checked how CDKN1A changes the levels of proteins linked to ferroptosis using Q-PCR and Western Blot. RESULTS: CDKN1A was found to negatively regulate the G1/S phase transition and was associated with ferroptosis in p53 signaling. Experiments in human renal tubular epithelial cells (HK-2) and rat NRK-52E cells showed that CDKN1A knockdown mitigated cisplatin-induced cell injury by reducing oxidative stress and ferroptosis. CONCLUSION: Our integrated approach identified CDKN1A as a biomarker for cisplatin-induced AKI. Its regulation could be key in AKI pathogenesis, offering new therapeutic insights and aiding in early diagnosis and intervention.
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Staphylococcus aureus (S. aureus) is a prevalent foodborne pathogen that poses significant challenges to food safety. Herein, a sensitive and specific electrochemical biosensor based on RPA-CRISPR/Cas12a is developed for evaluating S. aureus. In the presence of S. aureus, the extracted target DNA fragments are efficiently amplified by recombinase polymerase amplification (RPA). The designed crRNA, binding to Cas12a, effectively recognizes the target fragment cleaving hpDNA. The signal molecule of hpDNA is cleaved from the sensing interface, resulting in a reduction of current response. Under optimal experimental conditions, the developed electrochemical biosensor exhibits remarkable sensitivity in detecting S. aureus. The linear range for quantifying S. aureus in pure culture is 1.04 × 101-1.04 × 108 CFU/mL, with a detection limit as low as 3 CFU/mL. In addition, the biosensor enables the accurate and sensitive detection of S. aureus in milk within a linear range of 1.07 × 101-1.07 × 107 CFU/mL. The electrochemical biosensor enhances anti-interference capability owing to the specific amplification of RPA primers and the single-base recognition ability of crRNA. The RPA-CRISPR/Cas12a biosensor exhibits exceptional anti-interference capability, precision, and sensitivity, thereby establishing a robust foundation for real-time monitoring of microbial contamination.
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The widespread use of endocrine disruptors (EDPs) has certain potential hazards to organisms and environments, and it is particularly important to develop effective pretreatment methods before detection of EDPs in complex samples. In this work, a novel magnetic nanocomposite decorated with layered double hydroxides (LDHs) and carbon dots (CDs) was designed and prepared for magnetic solid-phase extraction (MSPE) of EDPs (bisphenol S, bisphenol F, bisphenol A, bisphenol AF, diethylstilbestrol and 4-cumylphenol) combined with high-performance liquid chromatography-ultraviolet (HPLC-UV) detection. The prepared composites were characterized by field emission scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS), and the adsorption mechanism towards these EDPs might be mainly based on hydrogen bonds and π-π conjugation. Under the optimized conditions, the proposed method showed limits of detection within 0.05-0.50 µg L-1 and limits of quantitation within 0.2-2.0 µg L-1, and good linearity (R2 ≥ 0.9975) was presented in the range of 0.2-200 µg L-1. Finally, the Fe3O4@C@NiCo-LDH@CDs composite-based MSPE-HPLC-UV method was applied for enrichment and determination of EDPs in water, milk, and tea beverage samples with recoveries in the range of 81.2-119.8% and relative standard deviations below 9.7%.
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Heat stress at the flowering stage significantly impacts rice grain yield, yet the number of identified genes associated with rice heat tolerance at this crucial stage remains limited. This study focuses on elucidating the function of the heat-induced gene reduced heat stress tolerance 1 (OsRHS). Overexpression of OsRHS leads to reduced heat tolerance, while RNAi silencing or knockout of OsRHS enhances heat tolerance without compromising yield, as assessed by the seed setting rate. OsRHS is localized in the cytoplasm and mainly expressed in the glume and anther of spikelet. Moreover, OsRHS was found to interact with the HSP protein cHSP70-4, and the knockout of cHSP70-4 resulted in increased heat tolerance. Complementation assays revealed that the knockout of cHSP70-4 could restore the compromised heat tolerance in OsRHS overexpression plants. Additional investigation reveals that elevated temperatures can amplify the bond between OsRHS and cHSP70-4 within rice. Furthermore, our findings indicate that under heat stress conditions during the flowering stage, OsRHS plays a negative regulatory role in the expression of many stress-related genes. These findings unveil the crucial involvement of OsRHS and cHSP70-4 in modulating heat tolerance in rice and identify novel target genes for enhancing heat resilience during the flowering phase in rice.
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Anoikis resistance allows cancer cells to avoid death caused by detachment from the extracellular matrix's adhesion, enabling these cells to infiltrate and migrate to regions such as the peritoneum. This study emphasizes GRP94's involvement in anoikis resistance and peritoneal metastasis in gastric cancer (GC). It's found that GRP94 overexpression, linked to poor prognosis, was potentially due to SP1 and GRP94 promoter interactions, confirmed through dual luciferase reporter (DLR), chromatin immunoprecipitation (ChIP), and quantitative real-time PCR (real-time qPCR). Increased GRP94 enhanced GC cells' anoikis resistance and metastasis. Decreasing GRP94 had opposite effects, potentially through yes-associated protein (YAP)/TEAD1 axis inhibition, with raised YAP phosphorylation and decreased TEAD1 levels detected by western blotting (WB). Inhibiting YAP counteracted GRP94's effects on anoikis resistance and metastasis, while activating YAP reversed the effects of GRP94 reduction. Animal experiments verified GRP94's contribution to GC's peritoneal metastasis. In conclusion, our work highlights the effect of GRP94 on anoikis resistance, showing potential value in treating peritoneal metastasis of GC.
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The sludge contains many high-value biological materials. However, current extraction methods focus only on individual materials, neglecting the further extraction potential of the residual after extraction. This study used continuous extraction to extract extracellular polymeric substances (EPS) and proteins (PN) from sludge, verified the flame retardancy of EPS and the foaming properties of PN and finally analyzed the economic feasibility of continuous extraction. The results showed that continuous extraction increased the protein extraction from 857.11 mg/L to 1089.41 mg/L. EPS reduced the heat release rate of linen fabric from 379.2 (J/g·K) to 38.3 (J/g·K), and PN achieved foaming capacity and stability reaching 770% and 71%, meeting the standards of foam extinguishing agents. The binding form of EPS with linen fabric and the peptide content in PN are crucial factors affecting their application effectiveness. Economic analysis showed that continuous extraction reduced processing costs by 37.64% compared to traditional sludge disposal methods.
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Antimony selenosulfide (Sb2(S,Se)3) has obtained widespread concern for photovoltaic applications as a light absorber due to superior photoelectric features. Accordingly, various deposition technologies have been developed in recent years, especially hydrothermal deposition method, which has achieved a great success. However, device performances are limited with severe carrier recombination, relating to the quality of absorber and interfaces. Herein, bulk and interface defects are simultaneously suppressed by regulating heterogeneous nucleation kinetics with barium dibromide (BaBr2) introduction. In details, the Br adsorbs and dopes on the polar planes of cadmium sulfide (CdS) buffer layer, promoting the exposure of nonpolar planes of CdS, which facilitates the favorable growth of [hk1]-Sb2(S,Se)3 films possessing superior crystallinity and small interface defects. Additionally, the Se/S ratio is increased due to the replacement of S/Se by Br, causing a downshift of the Fermi levels with a benign band alignment and a shallow-level defect. Moreover, Ba2+ is located at grain boundaries by coordination with S and Se ions, passivating grain boundary defects. Consequently, the efficiency is increased from 7.70% to 10.12%. This work opens an avenue towards regulating the heterogeneous nucleation kinetics of Sb2(S,Se)3 film deposited via hydrothermal deposition approach to optimize its crystalline orientation and defect features.
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The application of camellia oil is limited by its susceptibility to oxidation and insolubility in water, particularly under high humidity and temperature conditions. In order to effectively reduce the oxidation rate of camellia oil, prolong the shelf life in order to improve the stability in storage under different conditions, this study encapsulates camellia oil in Pickering emulsions stabilized by Octenyl succinic acid (OSA) starch, achieving a 100-fold reduction in release rate and enhanced lipid oxidation stability. The smooth surface and complete particles of the emulsion were observed and no new chemical bonds were formed. The minimum particle sizes were 1.72⯵m and 2.73⯵m, when the Pickering emulsion was set at pHâ¯6 and 0.1â¯M NaCl. In the digestion process, the microstructures observed that Pickering emulsion possessed super stability against oral and gastric digestions, prolonged the release time and improved the bioavailability compared with camellia oil, and the digestibility of the emulsion was 56.16â¯% within 120â¯min. All these results indicate that OSA-starch stabilized camellia oil can effectively increase solubility, improve stability and expand the application range.
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With the proceeding of global warming and water eutrophication, the phenomenon of green tide has garnered significant societal interest. Consequently, researchers had increasingly focused on the potential applications of green algae biomass, particularly its polysaccharides. The polysaccharide serves as the primary active constituent of green algae and has demonstrated numerous advantageous biological activities, including antioxidant, antiviral, anticoagulant, hypolipidemic and immuno-modulatory activities. The favorable bioavailability and solubility of green algae oligosaccharides are attributed to their low molecular weight. So there has been a growing interest in researching green algae polysaccharides and oligosaccharides for the utilization of marine biological resources. This review summarized the extraction, purification, chemical structure, composition, biological activity, and potential applications prospect of polysaccharides and oligosaccharides derived from green algae. The review could be helpful for expanding the applications of polysaccharides and oligosaccharides of green algae.
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Background: Ocular comorbidities of hidradenitis suppurativa (HS) has been widely evaluated; however real-world evidence was scarce. Moreover, risk of glaucoma in HS patients remained unclear. This study aimed to evaluate the 5-year glaucoma risk in HS patients. Methods: This retrospective cohort study used the TriNetX database covering 2005-2017. In total, 53,281 HS patients were propensity score matched 1:1 to controls based on demographics, including comorbidities, medications, healthcare utilization, etc. Patients were followed for 5 years post-index date. Glaucoma risks were calculated based on hazard ratios and 95% confidence intervals (95% CI). Stratified analyses by sex and age were performed. Results: After matching, baseline characteristics were similar between groups. HS was associated with a 1.25 times higher 5-year glaucoma risk (95% CI, 1.10-1.42). The risk was significant within 1 year (HR=1.37; 95% CI, 1.03-1.82), 3 years (HR=1.31; 95% CI, 1.12-1.54), and 5 years post-index. In subgroup analysis, women had a 1.28 times higher risk (95% CI, 1.10-1.49). Patients aged 18-64 years (HR=1.33; 95% CI, 1.14-1.55) and ≥65 years (HR=1.33; 95% CI, 1.05-1.67) also presented elevated glaucoma risks. Conclusion: This real-world data analysis demonstrated a significantly increased 5-year glaucoma risk in HS patients versus matched controls. Ocular complications should be concerned while managing HS patients.
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Glaucoma , Hidradenite Supurativa , Pontuação de Propensão , Humanos , Feminino , Masculino , Hidradenite Supurativa/epidemiologia , Hidradenite Supurativa/complicações , Adulto , Estudos Retrospectivos , Pessoa de Meia-Idade , Glaucoma/epidemiologia , Glaucoma/etiologia , Fatores de Risco , Adulto Jovem , Idoso , Comorbidade , Medição de Risco/estatística & dados numéricos , Bases de Dados Factuais/estatística & dados numéricosRESUMO
Predicting drug-target interactions (DTI) is a crucial stage in drug discovery and development. Understanding the interaction between drugs and targets is essential for pinpointing the specific relationship between drug molecules and targets, akin to solving a link prediction problem using information technology. While knowledge graph (KG) and knowledge graph embedding (KGE) methods have been rapid advancements and demonstrated impressive performance in drug discovery, they often lack authenticity and accuracy in identifying DTI. This leads to increased misjudgment rates and reduced efficiency in drug development. To address these challenges, our focus lies in refining the accuracy of DTI prediction models through KGE, with a specific emphasis on causal intervention confidence measures (CI). These measures aim to assess triplet scores, enhancing the precision of the predictions. Comparative experiments conducted on three datasets and utilizing 9 KGE models reveal that our proposed confidence measure approach via causal intervention, significantly improves the accuracy of DTI link prediction compared to traditional approaches. Furthermore, our experimental analysis delves deeper into the embedding of intervention values, offering valuable insights for guiding the design and development of subsequent drug development experiments. As a result, our predicted outcomes serve as valuable guidance in the pursuit of more efficient drug development processes.
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Background: Total knee replacement (TKR) is a common surgical procedure for osteoarthritis (OA) patients. TKR may increase susceptibility to herpes zoster (HZ) by inducing immunosuppression, surgical stress, and nerve injury. However, limited data exist on the relationship between TKR and HZ. This study examined the risk of HZ over time among OA patients who underwent TKR and those who did not, using a large population-based cohort. Method: Utilizing the TriNetX research network, people with OA and underwent TKR were recruited as case group. After 1:1 propensity score matching, OA patients who never experienced TKR were included as control group. Covariates, including demographics, comorbidities, and laboratory data, were balanced using propensity score matching. A 5-year follow-up assessed the hazard ratio of incident HZ and related complications. Results: Compared to the control group, a significantly elevated risk of HZ was observed in the TKR cohort across 5-year follow-up period, with the hazard ratio of 1.223 (95% CI: 1.089-1.373). Zoster without complications presented 1.173-fold risk in TKR patients while comparing with non-TKR controls. However, most other secondary outcomes related to HZ complications-such as encephalitis, neurological involvement, ocular disease, and disseminated zoster-did not show a significant increase in risk. The risk of HZ was statistically significant for females and older adults in the TKR cohort than in the control cohort. Conclusions: OA patients who underwent TKR had an increased risk of HZ compared to those who did not receive the procedure, especially females and older adults. These findings highlight the need for HZ monitoring/prevention protocols and further research on mitigating viral reactivation after major joint surgery.
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Artroplastia do Joelho , Herpes Zoster , Osteoartrite do Joelho , Pontuação de Propensão , Humanos , Herpes Zoster/epidemiologia , Herpes Zoster/etiologia , Artroplastia do Joelho/efeitos adversos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Osteoartrite do Joelho/cirurgia , Osteoartrite do Joelho/epidemiologia , Fatores de Risco , Incidência , SeguimentosRESUMO
In this study, free radicals generated by ultrasound were used to prepare conjugates of food proteins (soybean protein isolates, sodium caseinate and gelatin) with epigallocatechin gallate (EGCG). The changes in free amino and sulfhydryl group contents were used to confirm the occurrence of conjugation. The formation of covalent interactions on surface hydrophobicity, functional groups, structures, thermal stability, and gelation behavior of three proteins were investigated. The results showed that conjugation led to decrease in free amino and sulfhydryl group contents, reduction in the intensity of amide A and fluorescence intensity, and increase in ß-fold content. The conjugation also resulted in a decrease in surface hydrophobicity and thermal stability of soybean protein isolates and sodium caseinate, but an increase in the surface hydrophobicity and thermal stability of gelatin. Furthermore, the covalent bonding between proteins and EGCG improved gel strength, water holding capacity, and resulted in a denser and more compact microstructure.
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Although enrofloxacin (ENR) is a widely used broad-spectrum antibiotic in veterinary medicine, its residues in animals can pose a risk to human health. Thus, we developed a new method for detecting ENR based on aptamers and AuNPs. In the absence of ENR, the aptamers attached to the surface of the AuNPs via electrostatic interactions to protect the AuNPs from NaCl, and the solution remained red. Conversely, the aptamer bonded with ENR, leading the aptamer to detach from the AuNP surface, and the color of the solution changed from red to blue. Based on this principle, ENR can be qualitatively detected by the naked eye and quantitatively detected by measuring the absorbance ratio at 650 nm and 530 nm. The experimental results showed a good linear relationship within the ENR concentration range of 0-400 nM, with a limit of detection (LOD) of 1.72 nM, which is satisfactory for detection in food safety. Additionally, this method has also been successfully applied to the detection of ENR in tap water, river water, milk, serum and urine, with good recovery rates and RSD values of less than 7%, indicating its great potential for ENR detection in environmental water samples. More importantly, the combination of this method with a smartphone platform provided great convenience for on-site and visual detection of ENR, offering promising applicability prospects.
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Introduction: This study aims to explore the impact of economic agglomeration on the urban prosperity through economies of scale and agglomeration, it may also affect the public health of the agglomeration area. Methods: This paper takes 280 cities in China as the research object, and explores the impact of economic agglomeration on public health through a two-way fixed effects model, instrumental variable method, and generalized moment estimation. Results: The results indicate that: (1) the improvement of China's economic agglomeration can significantly promote urban public health, and economic agglomeration is a prerequisite for the improvement of urban public health, but there is no reverse causal relationship. (2) The enhancement of economic agglomeration in Northeast China has the greatest promotion effect on public health, followed by the eastern, western, and central regions; The economic agglomeration enhancement of the pilot medical group in closely connected cities has a greater promoting effect on public health than the pilot medical group in non-closely connected cities. (3) Empirical results based on micro sample data show that the improvement of economic agglomeration will also promote the increase of the number of public hospitals in cities. Discussion: This study emphasizes the important role of economic accumulation in the improvement of urban public health and provides empirical support for future economic development policies and practices.