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1.
Materials (Basel) ; 17(10)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38793328

RESUMO

High-entropy alloys are promising candidates expected to be applied in transportation equipment serving in extreme environments due to their excellent properties. CoCrFeMnNi high-entropy alloy is a typical representative of them, and its low temperature performance is excellent. In this study, to evaluate the feasibility of forming HEA shells, the deformation behavior of CoCrFeMnNi under a plane-stress state at lower temperatures was thoroughly studied. Firstly, a thin-walled HEA tube was fabricated using hot extrusion and further formed into a thin shell for uniaxial tensile and biaxial bulging tests. Subsequently, uniaxial tensile tests at cryogenic temperatures were conducted. Both the strength and the ductility improves as the temperature decreases from -160 °C to -196 °C. Then, a systematic low-temperature bulging test was performed using isothermal dome tests and the thickness uniformity analysis of the bulged specimens was carried out. In addition, grain microstructural observation using EBSD was characterized analyze the possible deformation mechanism at the cryogenic temperature under the biaxial stress state. This study, for the first time, investigated the biaxial deformation behavior of HEA. Considering the plane-stress state deformation is the dominant type in the thin-walled shell deformation, this study enables us to provide direct guidance for various sheet-forming processes of HEAs.

2.
Ecotoxicol Environ Saf ; 277: 116389, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38657458

RESUMO

Microplastics (MPs), recognized as an emerging environmental menace, have been extensively investigated in both marine and terrestrial fauna. This study is comprehensive to investigate how polystyrene (PS) affects ruminant animals. The experimental design comprised 24 individually housed lambs, divided into a CON group (diet without PS) and three PS-exposed (25 µm, 50 µm, 100 µm) groups, each with six lambs, the exposure of PS was 100 mg/day, and the duration of exposure was 60 days. The study yielded noteworthy results: (ⅰ) PS leads to a decrease in average daily gain along with an increase in feed conversion rate. (ⅱ) PS decreases rumen ammonia nitrogen. The rumen microbiota diversity remains consistent. However, the relative abundance of Bacteroidetes and Actinobacteria increased in the PS-exposed groups, while the relative abundance of Coriobacteriales_incertae_Sedis and Prevotellaceae_YAB2003_group decreased. (ⅲ) PS leads to decrease in hemoglobin, thrombocytocrit, and albumin levels in lamb blood, thus triggering oxidative stress accumulation, along with swelling of the kidneys and liver. (ⅳ) PS inflicts severe damage to jejunum, consequently impacting digestion and absorption. (ⅴ) PS reduces meat quality and the nutritional value. In conclusion, PS-exposure inhibited lambs' digestive function, adversely affects blood and organs' health status, reducing average daily gain and negatively influencing meat quality. PS particles of 50-100 µm bring worse damage to lambs. This research aims to fill the knowledge void concerning MPs' influences on ruminant animals, with a specific focus on the meat quality of fattening lambs.


Assuntos
Poliestirenos , Rúmen , Animais , Ovinos , Poliestirenos/toxicidade , Gastroenteropatias/induzido quimicamente , Gastroenteropatias/veterinária , Inflamação/induzido quimicamente , Carne , Microbioma Gastrointestinal/efeitos dos fármacos , Aumento de Peso/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Microplásticos/toxicidade
3.
Front Genet ; 15: 1335223, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38596213

RESUMO

An increasing number of studies point to an association between mitochondrial proteins (MPs) and lung cancer (LC). However, the causal relationship between MPs and LC remains unclear. Consequently, our study employed a bidirectional Mendelian randomization (MR) analysis to explore the causal association between MPs and different pathological types of LC. A two-sample MR study was performed using the genome-wide association study (GWAS) data publicly available. We applied the primary inverse variance weighted (IVW) method along with additional MR methods to validate the causality between MPs and different pathological types of LC. To ensure the robustness of our findings, sensitivity analyses were employed. Moreover, we performed a bi-directional MR analysis to determine the direction of the causal association. We identified a total of seven MPs had significant causal relationships on overall LC, lung squamous cell carcinoma (LUSC), and small cell lung carcinoma (SCLC). We found two MPs had significant associations with overall LC, four MPs had significant associations with LUSC, and four MPs had significant associations with SCLC. Additionally, an MP was found to have a nominal relationship with LUSC. Moreover, no causality was found between MPs and lung adenocarcinoma (LUAD). Bidirectional MR showed no reverse effect between identified MPs and different pathological types of LC. In general, our findings of this MR study suggest causal associations of specific MPs with overall LC, LUSC, and SCLC. However, no such causality was found in LUAD.

4.
Plants (Basel) ; 13(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38475539

RESUMO

The water conservation capacity of the litter and soil layers of forest ecosystems improves the function of forest ecosystems in conserving soil and water. Plantation restoration plays a key role in preventing soil erosion. In order to evaluate the water conservation capacity of plantation restoration in Latosol soil-eroded region, we analyzed the litter thickness and mass, water absorption process, water holding recovery process, and soil water holding capacity of five restoration types (Hevea brasiliensis, Acacia mangium, Eucalyptus robusta, Acacia-Eucalyptus, and Acacia-Hevea) in the Mahuangling Watershed, Hainan province. The results showed that the thickness of the litter ranged from approximately 3.42 ± 0.24 to 4.73 ± 0.81 cm, and the litter mass ranged from 5.04 ± 1.52 t·ha-1 to 13.16 ± 1.76 t·ha-1, with higher litter mass in the SL layer than in the UL layer. The litter mass of A. mangium was higher than that of H. brasiliensis, E. robusta, Acacia-Eucalyptus, and Acacia-Hevea, which was 3.16 ± 1.76 t·ha-1. A. mangium forest was significantly higher than other plantation restoration types in terms of the maximum water retention capacity (Qmax) and the effective water retention capacity (Qeff). The soil bulk weight ranged from approximately 1.52 ± 0.09 to 1.59 ± 0.08 g·cm-3, and porosity ranged from 31.77 ± 4.72 to 35.62 ± 3.02%, both of which increased with the depth of the soil layer. The water holding capacity of 0-60 cm soil varied from approximately 12.94 ± 7.91 to 45.02 ± 31.79 t·ha-1, with A. mangium having the best soil permeability and the strongest soil water holding capacity. The entropy weight method was used to conduct a comprehensive evaluation, and the results showed that the water conservation capacity of the soil layer was 1.26 times higher than that of the litter layer, in which the water conservation capacity of A. mangium was the strongest, with a comprehensive evaluation value of 0.2854, which effectively intercepted rainfall and reduced surface runoff. Hence, we suggest that the planting of A. mangium should be considered in future ecological restoration projects of the erosion area of Mahuangling in order to improve the function of conserving soil and water in a restoration forest ecosystem.

5.
J Clin Nurs ; 33(5): 1958-1975, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38439168

RESUMO

AIMS AND OBJECTIVES: To examine the effectiveness of family-centred interventions among family caregivers. BACKGROUND: Family-centred interventions are an emerging form of intervention that can be effective at improving physical and mental health outcomes for patients and family caregivers. To date, no reviews have examined the effectiveness of family-centred interventions for family caregivers. DESIGN: A systematic review, including a meta-analysis, was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA 2020) checklist. METHODS: Seven English and two Chinese electronic databases were compressively searched from the outset to March 2023. Two researchers independently reviewed the abstracts and full texts, extracted the data and assessed the risk of bias independently by using the Cochrane 'Risk of bias assessment tool'. RESULTS: This systematic review and meta-analysis included 20 articles. The results of the meta-analysis showed that family-centred interventions could significantly improve caregiver burden (p=0.003), quality of life (p = 0.007), depression (p = 0.0002), and stress (p < 0.0001) but not anxiety or family functioning. According to our subgroup analysis, the family-centred empowerment model (p = 0.009) was superior to the other family intervention (p=0.004) in reducing caregiver burden. Family-centred interventions are more effective at reducing the burden of caregiving on family caregivers of adolescent patients (SMD=-0.79, 95% CI[-1.22,-0.36], p = 0.0003) than on adult patients (SMD=-0.37, 95% CI [-0.61,-0.12], p = 0.004). CONCLUSIONS: Family-centred interventions could enhance family caregivers' burden, quality of life, stress and depression but had no significant impact on anxiety or family functioning. RELEVANCE TO CLINICAL PRACTICE: Family-centred interventions have the potential to improve the health status and caregiving burden of family caregivers. Rigorous and high-quality evidence is needed to confirm the long-term effects of these interventions on family caregivers. TRIAL REGISTRATION DETAILS: The protocol has been registered in the PROSPERO international prospective register of systematic reviews (Protocol registration ID: CRD42023453607).


Assuntos
Cuidadores , Qualidade de Vida , Adulto , Adolescente , Humanos , Cuidadores/psicologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Nível de Saúde , Ansiedade
6.
PLoS One ; 19(2): e0298303, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38358983

RESUMO

The plant growth-promoting rhizobacterium Tsukamurella tyrosinosolvens P9 can improve peanut growth. In this study, a co-culture system of strain P9 and peanut was established to analyze the transcriptome of peanut roots interacting with P9 for 24 and 72 h. During the early stage of co-culturing, genes related to mitogen-activated protein kinase (MAPK) and Ca2+ signal transduction, ethylene synthesis, and cell wall pectin degradation were induced, and the up-regulation of phenylpropanoid derivative, flavonoid, and isoflavone synthesis enhanced the defense response of peanut. The enhanced expression of genes associated with photosynthesis and carbon fixation, circadian rhythm regulation, indoleacetic acid (IAA) synthesis, and cytokinin decomposition promoted root growth and development. At the late stage of co-culturing, ethylene synthesis was reduced, whereas Ca2+ signal transduction, isoquinoline alkaloid synthesis, and ascorbate and aldarate metabolism were up-regulated, thereby maintaining root ROS homeostasis. Sugar decomposition and oxidative phosphorylation and nitrogen and fatty acid metabolism were induced, and peanut growth was significantly promoted. Finally, the gene expression of seedlings inoculated with strain P9 exhibited temporal differences. The results of our study, which explored transcriptional alterations of peanut root during interacting with P9, provide a basis for elucidating the growth-promoting mechanism of this bacterial strain in peanut.


Assuntos
Actinobacteria , Arachis , Cálcio , Arachis/metabolismo , Cálcio/metabolismo , Plântula/metabolismo , Etilenos/metabolismo , Raízes de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
7.
Medicine (Baltimore) ; 103(8): e36897, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38394497

RESUMO

BACKGROUND: Atopic dermatitis (AD) is a common and recurrent inflammatory disease with strong genetic susceptibility. The abnormal production of chemokines plays an important role in the occurrence and development of AD. METHODS: A comprehensive online literature search was performed in databases of China National Knowledge Infrastructure, Wanfang, VIP China Science and Technology Journal Database, China Biomedical Literature Database, PubMed, Embase and Cochrane Library to retrieve relevant articles published from January 2000 to October 2022. The odds ratio (OR) with its 95% confidence interval (CI) was employed to calculate this relationship. RESULTS: A total of 7 studies were finally screened out, including 1316 AD patients and 1099 controls. There were 3 studies for CC chemokine ligand 5 (CCL5) polymorphisms, 2 for CCL11 polymorphisms, and 2 for CCL17 polymorphisms, respectively. The meta-analysis revealed a significant association between the CCL5 - 403G/A polymorphism and AD under the allelic model (A vs G: OR = 1.25, 95% CI = 1.02-1.52, P = .03), heterozygous model (AG vs GG: OR = 1.40, 95% CI = 1.08-1.80, P = .01) and dominant model (AA + AG vs GG: OR = 1.38, 95% CI = 1.08-1.76, P = .01) in a fixed-effect model. The allelic model (G vs C: OR = 1.46, 95% CI = 1.07-1.98, P < .01) and dominant model (GG + GC vs CC: OR = 1.74, 95% CI = 1.23-2.47, P < .001) of the CCL5 - 28C/G polymorphism were also associated with an increased risk of AD. However, this significant association was not found in other alleles and genotypes (P > .05). CONCLUSION: Our results show that the A allele, AG and AA + AG genotypes of the CCL5 - 403G/A polymorphism, the G allele and GG + GC genotype of the CCL5 - 28C/G polymorphism are risk factors for AD. Future studies with large population are still needed to further explore those correlations.


Assuntos
Quimiocina CCL11 , Quimiocina CCL17 , Quimiocina CCL5 , Dermatite Atópica , Humanos , Quimiocina CCL11/genética , Quimiocina CCL17/genética , Quimiocina CCL5/genética , Dermatite Atópica/genética , Predisposição Genética para Doença , Genótipo , Ligantes , Polimorfismo de Nucleotídeo Único , Fatores de Risco
8.
Cell Mol Immunol ; 21(3): 213-226, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38177245

RESUMO

Despite the tremendous progress of chimeric antigen receptor T (CAR-T) cell therapy in hematological malignancies, their application in solid tumors has been limited largely due to T-cell exhaustion in the tumor microenvironment (TME) and systemic toxicity caused by excessive cytokine release. As a key regulator of the immunosuppressive TME, TGF-ß promotes cytokine synthesis via the NF-κB pathway. Here, we coexpressed SMAD7, a suppressor of TGF-ß signaling, with a HER2-targeted CAR in engineered T cells. These novel CAR-T cells displayed high cytolytic efficacy and were resistant to TGF-ß-triggered exhaustion, which enabled sustained tumoricidal capacity after continuous antigen exposure. Moreover, SMAD7 substantially reduced the production of inflammatory cytokines by antigen-primed CAR-T cells. Mechanistically, SMAD7 downregulated TGF-ß receptor I and abrogated the interplay between the TGF-ß and NF-κB pathways in CAR-T cells. As a result, these CAR-T cells persistently inhibited tumor growth and promoted the survival of tumor-challenged mice regardless of the hostile tumor microenvironment caused by a high concentration of TGF-ß. SMAD7 coexpression also enhanced CAR-T-cell infiltration and persistent activation in patient-derived tumor organoids. Therefore, our study demonstrated the feasibility of SMAD7 coexpression as a novel approach to improve the efficacy and safety of CAR-T-cell therapy for solid tumors.


Assuntos
Neoplasias , Receptores de Antígenos Quiméricos , Animais , Humanos , Camundongos , Citocinas/metabolismo , Imunoterapia Adotiva , Neoplasias/terapia , NF-kappa B/metabolismo , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/metabolismo , Proteína Smad7/genética , Proteína Smad7/metabolismo , Linfócitos T , Fator de Crescimento Transformador beta/metabolismo , Microambiente Tumoral
9.
Environ Sci Pollut Res Int ; 31(7): 10689-10701, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38206462

RESUMO

The frozen period interaction of groundwater and lakes is crucial for hydrological properties and aquatic ecology in cold and arid regions. In this study, we investigate the spatial hydrochemical characteristics, influencing factors in the Hulun Lake basin. The hydrochemical type of lake water exhibits Na-HCO3-SO4-Cl, while river shows a primary classification of Na-Ca-HCO3. Groundwater in the eastern and western regions is characterized by Na-SO4-Cl and Na-HCO3, respectively. Silicic acid and ion exchange predominantly influence groundwater chemistry in the western region, whereas evaporation and concentration play a major role in the eastern region. Total dissolved solids, Cl-, and F- emerge as the primary influencing factors of hydrochemical components in the Hulun Lake basin. Ion content decreased from the southern to the northern region, with the lowest value occurring near the Urson River. The high-temperature water body is primarily distributed in the central and southern regions of the lake. Based on characteristic ions and partial characteristics of ice surface temperature, the potential groundwater discharge areas near the inlet of the Xinkai River, the central and southern region are determined. This study reveals the hydrochemical characteristics, vertical ice distribution, and provides a scientific foundation for water resource management in cold and arid regions.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Lagos , Monitoramento Ambiental , Gelo , Tecnologia de Sensoriamento Remoto , Poluentes Químicos da Água/análise , Água Subterrânea/química , Qualidade da Água , China
10.
J Am Chem Soc ; 145(43): 23832-23841, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37850961

RESUMO

Norepinephrine (NE) is a key neurotransmitter in the central and sympathetic nervous systems, whose content fluctuates dynamically and rapidly in various brain regions during different physiological and pathophysiological processes. However, it remains a great challenge to directly visualize and precisely quantify the transient NE dynamics in living systems with high accuracy, specificity, sensitivity, and, in particular, high temporal resolution. Herein, we developed a series of small-molecular probes that can specifically detect NE through a sequential nucleophilic substitution-cyclization reaction, accompanied by a ratiometric near-infrared fluorescence response, within an impressively short time down to 60 ms, which is 3 orders of magnitude faster than that of present small-molecular probes. A unique water-promoted intermolecular proton transfer mechanism is disclosed, which dramatically boosted the recognition kinetics by ∼680 times. Benefiting from these excellent features, we quantitatively imaged the transient endogenous NE dynamics under external stimuli at the single living neuron level and further revealed the close correlations between NE fluctuations and Parkinson's disease pathology at the level of acute brain slices and live mouse brains in vivo.


Assuntos
Encéfalo , Norepinefrina , Animais , Camundongos , Encéfalo/diagnóstico por imagem , Sondas Moleculares , Imagem Óptica , Neurônios
11.
Pediatr Allergy Immunol ; 34(9): e14024, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37747750

RESUMO

BACKGROUND: Asthma is an inflammatory disease. The potential of n-3 polyunsaturated fatty acids (PUFAs) to alleviate asthma symptoms through their anti-inflammatory effects and immune modulation has been explored. However, the precise role of dietary n-3 PUFAs in childhood and adolescent asthma remains unclear. OBJECTIVE: This study aimed to evaluate the association between dietary n-3 PUFAs intake and asthma in children and adolescents in the United States. METHODS: We conducted a cross-sectional analysis of 8543 children and adolescents from the National Health and Nutrition Examination Survey (NHANES) between 2013 and 2020 by adjusting for covariates and using multivariate logistic regression, restricted cubic spline, threshold effects, and subgroup analyses. RESULTS: Among 8354 participants, 1456 (16.5%) self-reported diagnosis of asthma by a healthcare provider. After adjusting for potential confounding factors, compared with individuals in the lowest n-3 PUFA consumption group (T1, <26.07 mg/kg/day), the adjusted odds ratio (OR) for asthma was 0.71 (95% CI: 0.6-0.84, p < .001) in the second group (T2, 26.07-48.93 mg/kg/day) and 0.58 (95% CI: 0.47-0.73, p < .001) in the third group (T3, >48.93 mg/kg/day). Furthermore, a nonlinear (L-shaped) relationship was observed between n-3 PUFA intake and asthma (p = .009), with subgroup and sensitivity analyses confirming the stability of the results. In the threshold analysis, a critical turning point was observed at approximately 59.0 mg/kg/day (OR = 0.984, 95% CI: 0.977-0.991, p < .001). CONCLUSION: Dietary intake of n-3 PUFAs exhibited an L-shaped relationship with asthma in children and adolescents in the United States, with a critical turning point observed at approximately 59.0 mg/kg/day.


Assuntos
Asma , Ácidos Graxos Ômega-3 , Adolescente , Humanos , Criança , Estudos Transversais , Inquéritos Nutricionais , Asma/epidemiologia , Ácidos Graxos
12.
Arch Med Sci ; 19(5): 1270-1280, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37732066

RESUMO

Introduction: The present study aimed to investigate the differences in the proteomic expression between uncomplicated parapneumonic pleural effusion (UPPE) and complicated parapneumonic pleural effusion (CPPE). Material and methods: There were 10 patients with UPPE and 10 patients with CPPE. These patients were combined due to the complication of pleural effusion and further divided into group A and group B. An LC-MS analysis was conducted with the extraction of high-abundance proteins, and proteins with 1.5-fold or higher difference multiples were identified as differential proteins. Then, gene ontology (GO) and KEGG analyses were conducted on the differential proteins between the groups. Results: Compared with the UPPE group, there were 38 upregulated proteins and 29 downregulated proteins in the CPPE group. The GO analysis revealed that the CPPE group had enhanced expressions in monosaccharide biosynthesis, glucose catabolism, fructose-6-phosphate glycolysis, glucose-6-phosphate glycolysis, and NADH regeneration as well as reduced expressions in fibrinogen complexes, protein polymerization, and coagulation. Moreover, the KEGG analysis showed that the CPPE group had enhanced expressions in amino acid synthesis, the HIF-1 signalling pathway, and glycolysis/glycoisogenesis and decreased expressions in platelet activation and complement activation. Conclusions: In pleural effusion in patients with CPPE, there are enhanced expressions of proteins concerning glucose and amino acid metabolism, NADH regeneration, and HIF-1 signalling pathways together with decreased expressions of proteins concerning protein polymerization, blood coagulation, platelet activation, and complement activation.

13.
Anim Sci J ; 94(1): e13871, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37720923

RESUMO

Our objective was to determine effects of feeding lamb's peony byproducts, including stem and leaves (PSL), root (PR), and seeds meal (PSM), on growth, rumen fermentation, slaughter parameters, and meat quality. Sixty-four lambs (14.0 ± 2.1 kg) were allocated into eight treatments based on BW: no additives (CON), 0.15% aureomycin (CONA), low/high levels of PSL (5%/10% PSL replaced 5%/10% Chinese hay), PR (basal diet with 0.5%/1.0% PR), PSM (5%/10% PSM replaced 5%/10% soybean meal). Growth, digestibility, and rumen fermentation had dose responses whereas slaughter parameters, meat quality, or amino acids indexes were not. Peony byproducts increased DMI (p < 0.001) compared to CON, but higher levels were more advantageous (p = 0.003). However, low levels of peony byproducts decreased the NH3 -N concentration, but increased total volatile fatty acids mole percent more than high levels of that (p < 0.001). All peony byproducts increased dressing percentage (p < 0.05), increased pH and tenderness than CON (p < 0.05). In addition, PSL and PSM improved amino acid profiles of meat compared to CON, and were even better than CONA (p < 0.05). Therefore, peony byproducts not only improved animal growth but also reduced the frequency of antibiotic use in animal feeding.


Assuntos
Paeonia , Rúmen , Ovinos , Animais , Rúmen/metabolismo , Fermentação , Antibacterianos/farmacologia , Carneiro Doméstico , Carne/análise , Dieta/veterinária , Ração Animal/análise , Digestão
14.
Sci Rep ; 13(1): 12076, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37495578

RESUMO

Glaucoma is an acquired optic neuropathy, which can lead to irreversible vision loss. Deep learning(DL), especially convolutional neural networks(CNN), has achieved considerable success in the field of medical image recognition due to the availability of large-scale annotated datasets and CNNs. However, obtaining fully annotated datasets like ImageNet in the medical field is still a challenge. Meanwhile, single-modal approaches remain both unreliable and inaccurate due to the diversity of glaucoma disease types and the complexity of symptoms. In this paper, a new multimodal dataset for glaucoma is constructed and a new multimodal neural network for glaucoma diagnosis and classification (GMNNnet) is proposed aiming to address both of these issues. Specifically, the dataset includes the five most important types of glaucoma labels, electronic medical records and four kinds of high-resolution medical images. The structure of GMNNnet consists of three branches. Branch 1 consisting of convolutional, cyclic and transposition layers processes patient metadata, branch 2 uses Unet to extract features from glaucoma segmentation based on domain knowledge, and branch 3 uses ResFormer to directly process glaucoma medical images.Branch one and branch two are mixed together and then processed by the Catboost classifier. We introduce a gradient-weighted class activation mapping (Grad-GAM) method to increase the interpretability of the model and a transfer learning method for the case of insufficient training data,i.e.,fine-tuning CNN models pre-trained from natural image dataset to medical image tasks. The results show that GMNNnet can better present the high-dimensional information of glaucoma and achieves excellent performance under multimodal data.


Assuntos
Glaucoma , Metadados , Humanos , Redes Neurais de Computação , Interpretação de Imagem Assistida por Computador/métodos , Glaucoma/diagnóstico por imagem , Aprendizado de Máquina
15.
Anal Chim Acta ; 1271: 341477, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37328253

RESUMO

An efficient photoelectrochemical (PEC) sensing platform was developed for detection of di-2-ethylhexyl phthalate (DEHP) based on nitrogen and sulfur co-doped graphene quantum dots/TiO2 nanorods (N, S-GQDs/TiO2 NRs) coupling with exonuclease I (Exo I)-assisted target recycling for remarkable signal amplification. N, S-GQDs uniformly grown on TiO2 NRs by simple hydrothermal method showed high electron-hole separation efficiency and superior photoelectric performance, which was explored as the photoactive substrate for anchoring anti-DEHP aptamer and its complementary DNA (cDNA). With the addition of DEHP, aptamer molecules fell from the electrode surface owing to the specific recognition of aptamer to DEHP, resulting in the increment of photocurrent signal. At this moment, Exo I could stimulate aptamer hydrolysis in the aptamer-DEHP complexes, so that DEHP was released from the complexes to take part in the next reaction cycling, which remarkably increasing the photocurrent response and achieving signal amplification. The designed PEC sensing platform exhibited excellent analytical performance for DEHP with a low detection limit of 0.1 pg L-1. Also, its applications in real samples were further investigated in detail. Thus, the established method would provide a simple and efficient tool for DEHP or other pollutants monitoring in the environment.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Grafite , Nanotubos , Pontos Quânticos , Pontos Quânticos/química , Grafite/química , Técnicas Eletroquímicas/métodos , DNA Complementar , Aptâmeros de Nucleotídeos/química , Nanotubos/química , Técnicas Biossensoriais/métodos , Limite de Detecção
16.
Anal Chem ; 95(27): 10178-10185, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37368510

RESUMO

It is significantly vital to develop a convenient assay method in clinical treatment due to an atypically low abundance (∼5 µM) of bleomycin (BLM) used in clinics. Herein, an electrochemiluminescence (ECL) biosensor using a zirconium-based metal-organic frameworks (Zr-MOFs) as an intramolecular coordination-induced electrochemiluminescence (CIECL) emitter was proposed for sensitive detection of BLM. Zr-MOFs were synthesized using Zr(IV) as metal ions and 4,4',4″-nitrilotribenzoic acid (H3NTB) as ligands for the first time. The H3NTB ligand not only acts as coordination units bonding with Zr(IV) but functions as a coreactant to enhance ECL efficiency rooted in its tertiary nitrogen atoms. Specifically, a long guanine-rich (G-rich) single-stranded DNA (ssDNA) was released by the target-BLM-controlled DNA machine that could perform π-π stacking with another G-quadruplex, ssDNA-rhodamine B (S-RB), by shearing DNA's fixed sites 5'-GC-3' and the auxiliary role of exonuclease III (Exo III). Finally, due to the quenching effect of rhodamine B, a negative correlation trend was obtained between ECL intensity and BLM concentration in the range from 5.0 nM to 50 µM and the limit of detection was 0.50 nM. We believe that it is a promising approach to guide the preparation of CIECL-based functional materials and establishment of analytical methods.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas , Técnicas Biossensoriais/métodos , Zircônio , Técnicas Eletroquímicas , DNA/química , Bleomicina/análise , Bleomicina/química
17.
Analyst ; 148(12): 2709-2716, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37231936

RESUMO

The detection of 4-aminophenol (4-AP) is of critical importance due to its high toxicity, and the development of accurate, sensitive, and portable methods for this purpose is essential. Here, a facile colorimetric and electrochemical dual-mode sensor based on a CuO nanorod-decorated hemin-functionalized graphene nanocomposite (CuO/H-Gr) is successfully constructed for the detection of 4-AP. CuO/H-Gr exhibited superior peroxidase-mimicking activity, catalyzing the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) by H2O2 and generating a colorimetric signal. The catalytic system was found to contain hydroxyl radicals, as revealed by reactive oxygen species trials. Meanwhile, TMB was found to be an electroactive indicator that could be oxidized on a glassy carbon electrode. In the presence of CuO/H-Gr and H2O2, an enhanced electrochemical signal of TMB was generated. Upon the addition of 4-AP, the catalytic performance of CuO/H-Gr in the oxidation of TMB was significantly reduced, leading to a decrease in colorimetric and electrochemical signals. Based on this, a dual-mode sensor for the detection of 4-AP was developed. The linear response ranges for colorimetric and electrochemical sensors are 1.00-200 µM and 0.0100-300 µM, with detection limits of 0.687 µM and 0.00756 µM, respectively. Real water samples were tested to estimate the feasibility of the dual-mode sensor, and the recoveries were found to be consistent with those obtained by high-performance liquid chromatography. In addition, a smartphone-based assay was used to evaluate the levels of 4-AP, which opened a new path for on-site detection.


Assuntos
Grafite , Nanotubos , Grafite/química , Peroxidase/química , Hemina/química , Colorimetria/métodos , Peróxido de Hidrogênio/química , Smartphone , Corantes
18.
Anal Chem ; 95(22): 8679-8686, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37218622

RESUMO

Improving the sensitivity and accuracy of bioimmunoassays has been the focus of research into the development of electrochemiluminescence (ECL) sensing platforms, as this is a critical factor in their application to practical analysis. In this work, an electrochemiluminescence-electrochemistry (ECL-EC) dual-mode biosensing platform based on an "off-on-super on" signals pattern strategy was developed for the ultrasensitive detection of Microcystin-LR (MC-LR). In this system, sulfur quantum dots (SQDs) are a novel class of ECL cathode emitter with almost no potentially toxic effects. The sensing substrate is made from rGO/Ti3C2Tx composites, whose huge specific surface area greatly reduces the possibility of aggregation-caused quenching of SQDs. The ECL detection system was constructed based on the ECL-resonance energy transfer (ERET) strategy, where methylene blue (MB) with an ECL receptor function was bound to the aptamer of MC-LR by electrostatic adsorption and the center actual distance between the donor and the acceptor was calculated to be 3.84 nm, which was verified to be in accordance with the ERET theory. Meanwhile, the introduction of Ag+ as an ECL signal-amplifying molecule greatly improved the sensitivity of sensing analysis. Based on the specific binding of MC-LR to the aptamer, the concentration of MC-LR was found to have a positive correlation with the ECL signal. Also, EC detection was realized with the benefit of the excellent electrochemical properties of MB. The dual-mode biosensor greatly improves the confidence of the detection, examination areas of 0.001-100 pg/mL with MC-LR for ECL and EC were obtained, and the detection limits are 0.17 and 0.24 pg/mL, respectively.


Assuntos
Técnicas Biossensoriais , Pontos Quânticos , Pontos Quânticos/química , Medições Luminescentes , Técnicas Eletroquímicas , Transferência de Energia , Oligonucleotídeos , Limite de Detecção
19.
Curr Microbiol ; 80(5): 190, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37079055

RESUMO

Wetlands are the most biologically diverse ecosystems on Earth. The isolation of Streptomyces strains from wetlands is helpful to study their diversity and functions in such habitats. In this study, six strains of Streptomyces were isolated from the rhizosphere soil of three plant species in the Huaxi Wetland at Guiyang and were identified as Streptomyces galilaeus, S. avidinii, S. albogriseolus, S. albidoflavus, S. spororaveus, and S. cellulosae, respectively. The six strains all solubilized phosphate, fixed nitrogen, and produced ACC deaminase and siderophores, and four strains also secreted indole-3-acetic acid. The six strains had the ability to resist to certain degrees of salinity, drought, and acidic/alkaline pH stress. In addition, the S. avidinii WL3 and S. cellulosae WL9 strains significantly promoted seed germination of mung bean, pepper, and cucumber, especially the WL3 strain. A pot experiment further showed that WL3 significantly promoted the growth of cucumber seedlings. Thus, strains of six species of Streptomyces with multiple plant growth-promoting characteristics were isolated from the wetland. These results lay a foundation for their potential use as microbial agents for seed-coating treatments.


Assuntos
Rizosfera , Streptomyces , Germinação , Áreas Alagadas , Verduras , Ecossistema , Sementes , China , Microbiologia do Solo
20.
Anal Chem ; 95(16): 6655-6663, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37018483

RESUMO

The essential expansion of electrochemiluminescence (ECL) technology into clinical detection relies on sensitive and stable signal and maintenance of the activity of the immune molecules during the analysis. This poses a critical challenge for an ECL biosensor as a luminophore in general requires high potential excitation resulting in a strong ECL signal; nevertheless, it has an irreversible effect on the activity of the antigen or antibody. Herein, a novel electrochemiluminescence (ECL) biosensor utilizing nitrogen-doped carbon quantum dots (N-CQDs) as emitters and molybdenum sulfide/ferric oxide (MoS2@Fe2O3) nanocomposites as a coreaction accelerator was developed for detection of neuron-specific enolase (NSE), a biomarker of small cell lung cancer. The doping of nitrogen allows the CQDs to exhibit ECL signals with low excitation potential, with a more viable activity possible for immune molecules. MoS2@Fe2O3 nanocomposites exhibit superior coreaction acceleration characteristics in hydrogen peroxide than any single component of them, and the highly branched dendrite microstructure provides a large number of binding sites for immune molecular, which is an inevitable factor for trace detection. In addition, ion beam sputtering gold particle technology is introduced into the sensor fabrication via an Au-N bond, which will provide sufficient density orientation for capturing the antibody load via the Au-N bonds. With excellent repeatability, stability, and specificity, the as-purposed sensing platform showed differentiated ECL responses of NSE range from 10.00 fg/mL to 500 ng/mL, and the limit of detection (LOD) was calculated of 6.30 fg/mL (S/N = 3). The proposed biosensor is prospective to provide a new avenue for the analysis of NSE or other biomarkers.


Assuntos
Técnicas Biossensoriais , Pontos Quânticos , Carbono/química , Pontos Quânticos/química , Medições Luminescentes/métodos , Nitrogênio/química , Molibdênio/química , Estudos Prospectivos , Técnicas Biossensoriais/métodos , Imunoensaio/métodos , Técnicas Eletroquímicas/métodos , Limite de Detecção
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