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1.
Front Pharmacol ; 15: 1375110, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38645557

RESUMO

Introduction: Head and neck cancer is one of the most common tumors worldwide. However, drug resistance in its treatment has become a major factor limiting the efficacy. This study aims to comprehensively understand the current status of research in this field. Methods: The study analyzes papers related to therapeutic resistance in head and neck cancer published between 2000 and 2023 in the Web of Science Core Collection To achieve the research objectives, we searched the WoSCC for research and review papers on therapeutic resistance in head and neck cancer from 2000 to 2023, screened the English literature, and analyzed the research hotspots, academic collaborations, and trends in detail using tools such as Citespace, SCImago Graphica, and VOS viewer. Results: This study summarizes 787 head and neck cancer treatment resistance publications from WoSCC. The analysis showed that China and the United States are the major contributors in this field, and Grandis Jennifer R and Yang Jai-Sing are the key scholars. Keyword analysis showed that "cisplatin resistance" is a continuing focus of attention, while "Metastasis" and "Ferroptosis" may be emerging research hotspots. Literature clustering analysis pointed out that "Ferroptosis", "Immunotherapy" and "ERK signaling" were the recent hotspots that received extensive attention and citations. Finally, we discuss the current status and challenges in drug-resistant therapies for head and neck cancer. Conclusion: This study is the first comprehensive bibliometric analysis of drug resistance in head and neck cancer. Reveals current trends and helps researchers grasp cutting-edge hotspots in the field.

2.
Oncol Lett ; 27(5): 221, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38586211

RESUMO

MicroRNAs (miRNAs) were previously demonstrated to be involved in the pathogenesis of non-small-cell lung cancer (NSCLC); however, the roles of certain miRNAs in NSCLC remain to be elucidated. The present study aimed to investigate the functions of screened miRNAs in NSCLC and the potential mechanisms. First, expression profiles of miRNAs were downloaded from the Gene Expression Omnibus (dataset no. GSE29248) and the differentially expressed miRNAs were analyzed by bioinformatics methods. Reverse transcription-quantitative PCR was used to validate the differential expression of miR-373 in clinical samples. The association between miR-373 expression levels and clinicopathological characteristics was also investigated. To further examine how miR-373 mediates the emergence of NSCLC, western blot, Cell Counting Kit-8, cell invasion and wound-healing assays, as well as apoptosis detection and a luciferase assay were used. The results indicated significant downregulation of miR-373 in NSCLC tissues and its low expression was closely associated with the degree of differentiation, clinical stage and tumor size, and was indicative of an unfavorable prognosis for patients with NSCLC. A functional study indicated that overexpression of miR-373 inhibited the proliferation, promoted apoptosis, and suppressed invasion and migration of NSCLC cells. Bioinformatics prediction and functional assays suggested that Grb-associated binding protein 2 (GAB2) was a direct target of miR-373. In addition, GAB2 was found to be significantly upregulated in NSCLC tissues, and clinically, miR-373 was negatively associated with GAB2. Furthermore, overexpression of GAB2 blocked the tumor suppressive effects of miR-373 on NSCLC cells. Mechanistically, miR-373 mimics were able to reduce the expression of GAB2 and subsequently decrease the phosphorylation level of AKT and mTOR protein. The present results indicate that miR-373 exerts its anti-tumor effects in NSCLC cells by targeting the GAB2/PI3K/AKT pathway, suggesting that miR-373 may be a potential therapeutic target in NSCLC.

3.
Anal Chim Acta ; 1299: 342406, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38499412

RESUMO

The hybridization chain reaction (HCR), as one of the nucleic acid amplification technologies, is combined with fluorescence signal output with excellent sensitivity, simplicity, and stability. However, current HCR-based fluorescence sensing methods still have some defects such as the blocking effect of the HCR combination with fluorophores and the aggregation-caused quenching (ACQ) phenomenon of traditional fluorophores. Herein, a triplex DNA-based aggregation-induced emission probe (AIE-P) was designed as the fluorescent signal transduction, which is able to provide a new platform for HCR-based sensing assay. The AIE-P was synthesized by attaching the AIE fluorophores to terminus of the oligonucleotide through amido bond, and captured the products of HCR to form triplex DNA. In this case, the AIE fluorophores were located in close proximity to generate fluorescence. This assay provided turn-on fluorescence efficiency with a high signal-to-noise ratio and excellent amplification capability to solve the shortcoming of HCR-based fluorescence sensing methods. It enabled sensitive detection of Vibrio parahaemolyticus in the range of 102-106 CFU mL-1, and with a low limit of detection down to 39 CFU mL-1. In addition, this assay expressed good specificity and practicability. The triplex DNA-based AIE probe forms a universal molecular tool for developing HCR-based fluorescence sensing methods.


Assuntos
Técnicas Biossensoriais , DNA , DNA/genética , DNA/química , Hibridização de Ácido Nucleico/métodos , Corantes Fluorescentes/química , Técnicas de Amplificação de Ácido Nucleico/métodos , Técnicas Biossensoriais/métodos , Limite de Detecção
4.
Biochem Pharmacol ; 222: 116061, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38369212

RESUMO

Activins are members of the transforming growth factor-ß (TGF-ß) superfamily and act as key regulators in various physiological processes, such as follicle and embryonic development, as well as in multiple human diseases, including cancer. They have been established to signal through three type I and two type II serine/threonine kinase receptors, which, upon ligand binding, form a final signal-transducing receptor complex that activates downstream signaling and governs gene expression. Recent research highlighted the dysregulation of the expression or activity of activin receptors in multiple human cancers and their critical involvement in cancer progression. Furthermore, expression levels of activin receptors have been associated with clinicopathological features and patient outcomes across different cancers. However, there is currently a paucity of comprehensive systematic reviews of activin receptors in cancer. Thus, this review aimed to consolidate existing knowledge concerning activin receptors, with a primary emphasis on their signaling cascade and emerging biological functions, regulatory mechanisms, and potential clinical applications in human cancers in order to provide novel perspectives on cancer prognosis and targeted therapy.


Assuntos
Ativinas , Neoplasias , Gravidez , Feminino , Humanos , Receptores de Ativinas , Ativinas/metabolismo , Proteínas Serina-Treonina Quinases , Fator de Crescimento Transformador beta/metabolismo , Neoplasias/tratamento farmacológico
5.
Cell Signal ; 114: 111002, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38048860

RESUMO

Laryngeal squamous cell carcinoma (LSCC) is one of the common malignant tumors in the head and neck region, and its high migration and invasion seriously threaten the survival and health of patients. In cancer development, m6A RNA modification plays a crucial role in regulating gene expression and signaling. This study delved into the function and mechanism of the m6A reading protein YTHDF1 in LSCC. It was found that YTHDF1 was highly expressed in the GEO database and LSCC tissues. Cell function experiments confirmed that the downregulation of YTHDF1 significantly inhibited the proliferation, migration, and invasion ability of LSCC cells. Further studies revealed that EIF4A3 was a downstream target gene of YTHDF1, and knockdown of EIF4A3 similarly significantly inhibited the malignant progression of LSCC in both in vivo and in vitro experiments. The molecular mechanism studies suggested that YTHDF1-EIF4A3 may promote the malignant development of LSCC by activating the EMT signaling pathway. This study provides important clues for an in-depth understanding of the pathogenesis of LSCC and is a solid foundation for the discovery of new therapeutic targets and approaches.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Laríngeas , MicroRNAs , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Carcinoma de Células Escamosas/patologia , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/metabolismo , Proliferação de Células/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Fator de Iniciação 4A em Eucariotos/genética , Fator de Iniciação 4A em Eucariotos/metabolismo , RNA Helicases DEAD-box/metabolismo , Proteínas de Ligação a RNA/metabolismo
6.
J Agric Food Chem ; 71(33): 12549-12557, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37552844

RESUMO

Nucleotide sugars are essential precursors for carbohydrate synthesis but are in scarce supply. Uridine diphosphate (UDP)-glucose is a core building block in nucleotide sugar preparation, making its efficient synthesis critical. Here, a process for producing valuable UDP-glucose and functional mannose from sucrose was established and improved via a semirational sucrose synthase (SuSy) design and the accurate D-mannose isomerase (MIase) cascade. Engineered SuSy exhibited enzyme activity 2.2-fold greater than that of the WT. The structural analysis identified a latch-hinge combination as the hotspot for enhancing enzyme activity. Coupling MIase, process optimization, and reaction kinetic analysis revealed that MIase addition during the high-speed UDP-glucose synthesis phase distinctly accelerated the entire process. The simultaneous triggering of enzyme modules halved the reaction time and significantly increased the UDP-glucose yield. A maximum UDP-glucose yield of 83%, space-time yield of 70 g/L/h, and mannose yield of 32% were achieved. This novel and efficient strategy for sucrose value-added exploitation has industrial promise.


Assuntos
Uridina Difosfato Glucose , Uridina Difosfato Glucose/química , Uridina Difosfato Glucose/metabolismo , Sacarose/química , Sacarose/metabolismo , Mutação , Cinética , Modelos Moleculares , Manose/química , Manose/metabolismo , Estrutura Terciária de Proteína
7.
Environ Technol ; : 1-11, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37553118

RESUMO

The present work investigates the performance of a biofilm reactor filled with a new type of combined packing used to treat wastewater and explores a new technology approach for the application of coral sand and waste non-woven fabric. The combined packing was made of coral sand and waste non-woven fabric, which was used as a biofilm carrier to treat sewage. The experimental results showed that the removal efficiencies of COD, NH4+-N and TN in the biofilm reactor containing the combined packing were 92.9%, 72.9% and 63.2%, respectively. The maximum removal efficiencies of COD, NH4+-N and TN in the biofilm reactor containing single packing were 89.0%, 63.4% and 55.2%, respectively. The properties of the combined packing were characterized by Fourier Transform Infrared (FTIR), specific surface area, SEM and dehydrogenase activity. Infrared analysis showed that there were hydroxyl, carboxyl and carbonyl groups on the surface of coral sand and non-woven fabric which were beneficial for biofilm growth and wastewater treatment. The large pores in the interior of coral sand and non-woven fabric could provide a comfortable environment for microbes to grow and reproduce. The dehydrogenase activity of the biofilm on the surface of coral sand in the third biofilm reactor was 49.91 µgTF·g-1·h-1, which was significantly higher than that of the other two biofilm reactors. The new type of combined packing is suitable for biofilm carriers with low cost, which can be applied to actual sewage treatment projects. This study provides a reference for the practical application of the technique.

8.
Front Bioeng Biotechnol ; 11: 1176352, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37180036

RESUMO

A highly efficient strategy using Copper-Glycyl-L-Histidyl-L-Lysine (GHK-Cu) as a novel inducer was developed to enhance laccase production by Trametes versicolor. After medium optimization, laccase activity increased by 12.77-fold compared to that without GHK-Cu. The laccase production of 1113.8 U L-1 was obtained by scaling-up culture in 5-L stirring tank. The laccase production induced by CuSO4 was poorer than that of GHK-Cu at the same mole concentration. GHK-Cu could increase the permeability of cell membrane with less damage, and it facilitated the adsorption, accumulation, and utilization of copper by fungal cells, which was beneficial for laccase synthesis. GHK-Cu induced better expression of laccase related genes than that of CuSO4, resulting in higher laccase production. This study provided a useful method for induced production of laccase by applying GHK chelated metal ion as a non-toxic inducer, which reduced the safety risk of laccase broth and provided the potential application of crude laccase in food industry. In addition, GHK can be used as the carrier of different metal ions to enhance the production of other metalloenzymes.

9.
Front Neurosci ; 17: 1135991, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37034177

RESUMO

Objective: This study aims to compare the binocular visual functions and balance among monocular myopic adolescents and adults and binocular low myopic adolescents and explore whether monocular myopia requires glasses. Methods: A total of 106 patients participated in this study. All patients were divided into three groups: the monocular myopia children group (Group 1 = 41 patients), the monocular myopia adult group (Group 2 = 26 patients) and the binocular low myopia children group (Group 3 = 39 patients). The refractive parameters, accommodation, stereopsis, and binocular balance were compared. Results: The binocular refractive difference in Group 1, Group 2, and Group 3 was -1.37 ± 0.93, -1.94 ± 0.91, and -0.32 ± 0.27 D, respectively. Moreover, uncorrected visual acuity (UCVA), spherical equivalent (SE) and monocular accommodative amplitude (AA) between myopic and emmetropic eyes in Group 1 and Group 2 were significantly different (all P < 0.05). There was a significant difference in the accommodative facility (AF) between myopic and emmetropic eyes in Group 2 (t = 2.131, P = 0.043). Furthermore, significant differences were found in monocular AA (t = 6.879, P < 0.001), binocular AA (t = 5.043, P < 0.001) and binocular AF (t = -3.074, P = 0.003) between Group 1 and Group 2. The normal ratio of stereopsis according to the random dots test in Group 1 was higher than in Group 2 (χ2 = 14.596, P < 0.001). The normal ratio of dynamic stereopsis in Group 1 was lower than in Group 3 (χ2 = 13.281, P < 0.001). The normal signal-to-noise ratio of the binocular balance point in Group 1 was lower than Group 3 (χ2 = 4.755, P = 0.029). Conclusion: First, monocular myopia could lead to accommodative dysfunction and unbalanced input of binocular visual signals, resulting in myopia progression. Second, monocular myopia may also be accompanied by stereopsis dysfunction, and long-term uncorrected monocular myopia may worsen stereopsis acuity in adulthood. In addition, patients with monocular myopia could exhibit stereopsis dysfunction at an early stage. Therefore, children with monocular myopia must wear glasses to restore binocular balance and visual functions, thereby delaying myopia progression.

10.
Microorganisms ; 11(3)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36985345

RESUMO

Polysaccharides are crucial dietary supplements and traditional pharmacological components of Ganoderma lucidum; however, the mechanisms responsible for high polysaccharide yields in G. lucidum remain unclear. Therefore, we investigated the mechanisms underlying the high yield of polysaccharides in submerged cultures of G. lucidum using transcriptomic and proteomic analyses. Several glycoside hydrolase (GH) genes and proteins, which are associated with the degradation of fungal cell walls, were significantly upregulated under high polysaccharide yield conditions. They mainly belonged to the GH3, GH5, GH16, GH17, GH18, GH55, GH79, GH128, GH152, and GH154 families. Additionally, the results suggested that the cell wall polysaccharide could be degraded by GHs, which is beneficial for extracting more intracellular polysaccharides from cultured mycelia. Furthermore, some of the degraded polysaccharides were released into the culture broth, which is beneficial for obtaining more extracellular polysaccharides. Our findings provide new insights into the mechanisms underlying the roles that GH family genes play to regulate high polysaccharide yields in G. lucidum.

11.
BMC Genomics ; 24(1): 126, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36932328

RESUMO

BACKGROUND: Late embryogenesis abundant (LEA) proteins play an important role in dehydration process of seed maturation. The seeds of Panax notoginseng (Burkill) F. H. Chen are typically characterized with the recalcitrance and are highly sensitive to dehydration. However, it is not very well known about the role of LEA proteins in response to dehydration stress in P. notoginseng seeds. We will perform a genome-wide analysis of the LEA gene family and their transcriptional responses to dehydration stress in recalcitrant P. notoginseng seeds. RESULTS: In this study, 61 LEA genes were identified from the P. notoginseng genome, and they were renamed as PnoLEA. The PnoLEA genes were classified into seven subfamilies based on the phylogenetic relationships, gene structure and conserved domains. The PnoLEA genes family showed relatively few introns and was highly conserved. Unexpectedly, the LEA_6 subfamily was not found, and the LEA_2 subfamily contained 46 (75.4%) members. Within 19 pairs of fragment duplication events, among them 17 pairs were LEA_2 subfamily. In addition, the expression of the PnoLEA genes was obviously induced under dehydration stress, but the germination rate of P. notoginseng seeds decreased as the dehydration time prolonged. CONCLUSIONS: We found that the lack of the LEA_6 subfamily, the expansion of the LEA_2 subfamily and low transcriptional levels of most PnoLEA genes might be implicated in the recalcitrant formation of P. notoginseng seeds. LEA proteins are essential in the response to dehydration stress in recalcitrant seeds, but the protective effect of LEA protein is not efficient. These results could improve our understanding of the function of LEA proteins in the response of dehydration stress and their contributions to the formation of seed recalcitrance.


Assuntos
Panax notoginseng , Panax notoginseng/genética , Panax notoginseng/metabolismo , Desidratação/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Filogenia , Sementes/metabolismo , Desenvolvimento Embrionário , Regulação da Expressão Gênica de Plantas
12.
Acta Ophthalmol ; 101(5): 485-503, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36774646

RESUMO

Post-laser in situ keratomileusis (post-LASIK) ectasia (PLE) is one of the most serious complications after refractive surgery, mainly manifested as progressive thinning and trembling thinning of the cornea, accompanied by increased myopia and astigmatism. The mechanisms behind mainly include genetic risk factors and external environmental factors such as eye rubbing and cornea surgery. In order to achieve the goal of reducing the incidence of ectasia, preoperative screening strategies need to be continuously improved, through the collection and assessment of genetic and environmental risk factors. Although previous preoperative screening methods did not have a uniform standard, the emergence of artificial intelligence (AI) can help us process a large amount of information and make rational use of the data. By using high-fidelity finite element modelling, differences in preoperative and postoperative strain distributions can be observed, which can predict the risk of postoperative ectasia. In this review, we describe the incidence, aetiology, prevention and treatment of PLE for the purpose of comprehensive management. In terms of treatment, corneal collagen cross-linking has been widely used to treat progressive keratoconus and other ectasia disease, either as a preventive measure during surgery or as a therapeutic modality after surgery to prevent progression of corneal dilation. Although the standard Dresden protocol has been identified as the gold standard treatment for corneal dilatation, a series of refinements, investigations and long-term studies have been conducted in recent years. Thus, understanding the factors involved in delaying the onset and slowing progression of cornea ectasia will be key to reducing the incidence worldwide.


Assuntos
Doenças da Córnea , Ceratocone , Ceratomileuse Assistida por Excimer Laser In Situ , Humanos , Ceratomileuse Assistida por Excimer Laser In Situ/efeitos adversos , Topografia da Córnea/métodos , Dilatação Patológica/etiologia , Dilatação Patológica/prevenção & controle , Dilatação Patológica/diagnóstico , Inteligência Artificial , Córnea/cirurgia , Doenças da Córnea/diagnóstico , Doenças da Córnea/etiologia , Doenças da Córnea/prevenção & controle , Ceratocone/diagnóstico , Ceratocone/etiologia , Ceratocone/prevenção & controle , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos
13.
J Agric Food Chem ; 71(8): 3832-3841, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36795895

RESUMO

The restricted availability of UDP-glucose, an essential precursor that targets oligo/polysaccharide and glycoside synthesis, makes its practical application difficult. Sucrose synthase (Susy), which catalyzes one-step UDP-glucose synthesis, is a promising candidate. However, due to poor thermostability of Susy, mesophilic conditions are required for synthesis, which slow down the process, limit productivity, and prevent scaled and efficient UDP-glucose preparation. Here, we obtained an engineered thermostable Susy (mutant M4) from Nitrosospira multiformis through automated prediction and greedy accumulation of beneficial mutations. The mutant improved the T1/2 value at 55 °C by 27-fold, resulting in UDP-glucose synthesis at 37 g/L/h of space-time yield that met industrial biotransformation standards. Furthermore, global interaction between mutant M4 subunits was reconstructed by newly formed interfaces according to molecular dynamics simulations, with residue Trp162 playing an important role in strengthening the interface interaction. This work enabled effective, time-saving UDP-glucose production and paved the way for rational thermostability engineering of oligomeric enzymes.


Assuntos
Glucosiltransferases , Uridina Difosfato Glucose , Uridina Difosfato Glucose/metabolismo , Glucosiltransferases/química , Glucose , Simulação de Dinâmica Molecular , Sacarose/metabolismo
14.
Int J Mol Sci ; 24(4)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36835274

RESUMO

Ion exchange resins are suitable as carriers for immobilized enzymes because of their stable physicochemical properties, appropriate particle size and pore structure, and lower loss in continuous operation. In this paper, we report the application of the Ni-chelated ion exchange resin in the immobilization of His-tagged enzyme and protein purification. Acrylic weak acid cation exchange resin (D113H) was selected from four cationic macroporous resins that could chelate the transition metal ion Ni. The maximum adsorption capacity of Ni was ~198 mg/g. Phosphomannose isomerase (PMI) can be successfully immobilized on Ni-chelated D113H from crude enzyme solution through chelation of transition metal ions with the His-tag on the enzyme. The maximum amount of immobilized PMI on the resin was ~143 mg/g. Notably, the immobilized enzyme showed excellent reusability and maintained 92% of its initial activity with 10 cycles of catalytic reaction. In addition, PMI was successfully purified using an affinity chromatography column prepared by Ni-chelated D113H, which showed the potential for the immobilization and purification process to be realized in one step.


Assuntos
Enzimas Imobilizadas , Resinas de Troca Iônica , Proteínas , Quelantes/química , Cromatografia de Afinidade/métodos , Enzimas Imobilizadas/química , Indicadores e Reagentes , Proteínas/isolamento & purificação
15.
J Affect Disord ; 329: 141-148, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36842651

RESUMO

BACKGROUND: Suicide hotlines are widely used, with potential for identification of callers at especially high risk. METHODS: This prospective study was conducted at the largest psychological support hotline in China. From 2015 to 2017, all distressed callers were consecutively included and assessed, using a standardized scale consisting of 12 elements, yielding scores of high risk (8-16), moderate risk (4-7), and low risk (0-3) for suicidal act. All high-risk and half of moderate- and low-risk callers were scheduled for a 12-month follow-up. Main outcomes were suicidal acts (nonlethal attempt, death) over follow-up. RESULTS: Of 21,346 fully assessed callers, 5822, 11,791, and 3733 were classified as high-, moderate-, or low-risk for suicidal acts, with 8869 callers (4076 high-, 3258 moderate-, and 1535 low-risk) followed up over 12 months. Over follow-up, 802 (9.0 %) callers attempted suicide or died by suicide. The high-risk callers (15.1 %) had 3-fold higher risk for subsequent suicidal acts than moderate- (5.1 %) and 12-fold higher risk than low-risk callers (1.3 %). The weighted sensitivity, specificity, and positive predictive value of high risk scores were 56.4 %, 74.9 %, and 14.4 %. LIMITATIONS: Assessed callers with different risk levels were followed disproportionally. CONCLUSIONS: Suicidal risk assessment during a hotline call is both feasible and predictive of risk, guiding resource allocation to higher risk callers.


Assuntos
Linhas Diretas , Prevenção ao Suicídio , Humanos , Intervenção na Crise , Ideação Suicida , Estudos Prospectivos , Fatores de Risco , Medição de Risco
16.
Biosensors (Basel) ; 13(1)2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36671980

RESUMO

Soil microbial fuel cells (SMFCs) are an innovative device for soil-powered biosensors. However, the traditional SMFC sensors relied on anodic biosensing which might be unstable for long-term and continuous monitoring of toxic pollutants. Here, a carbon-felt-based cathodic SMFC biosensor was developed and applied for soil-powered long-term sensing of heavy metal ions. The SMFC-based biosensor generated output voltage about 400 mV with the external load of 1000 Ω. Upon the injection of metal ions, the voltage of the SMFC was increased sharply and quickly reached a stable output within 2~5 min. The metal ions of Cd2+, Zn2+, Pb2+, or Hg2+ ranging from 0.5 to 30 mg/L could be quantified by using this SMFC biosensor. As the anode was immersed in the deep soil, this SMFC-based biosensor was able to monitor efficiently for four months under repeated metal ions detection without significant decrease on the output voltage. This finding demonstrated the clear potential of the cathodic SMFC biosensor, which can be further implemented as a low-cost self-powered biosensor.


Assuntos
Fontes de Energia Bioelétrica , Técnicas Biossensoriais , Metais Pesados , Solo , Eletrodos
17.
Sens Actuators B Chem ; 379: 133252, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36590306

RESUMO

SARS-CoV-2, a highly transmissible and mutagenic virus, made huge threats to global public health. The detection strategies, which are free from testing site requirements, and the reagents and instruments are portable, are vital for early screening and play a significant role in curbing the spread. This work proposed a silver-coated glass slide (SCGS)/DNA walker based on a dual targets-triggering mechanism, enzyme-catalyzed amplification, and smartphone data analysis, which build a portable visual detection strategy for the SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) gene. By this method, the detection was reflected by the ultraviolet absorbance changes and visible color changes to the naked eye which was analyzed by Red-Green-Blue (RGB) data analysis via smartphone within 30 min, simplifying the detection process and shortening the detection time. Meanwhile, the dual targets-triggering mechanism and dual signal amplification strategy ensured detection specificity and sensitivity. Further, the practicability was verified by the detection of the real sample which provided this method an application potential in SARS-CoV-2 rapid detection.

18.
Anal Chem ; 95(5): 2628-2632, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36705511

RESUMO

A novel microfiber-like biohydrogel was fabricated by a facile approach relying on electroactive bacteria-induced graphene oxide reduction and confined self-assembly in a capillary tube. The microfiber-like biohydrogel (d = ∼1 mm) embedded high-density living cells and activated efficient electron exchange between cells and the conductive graphene network. Further, a miniature whole-cell electrochemical biosensing system was developed and applied for fumarate detection under -0.6 V (vs Ag/AgCl) applied potential. Taking advantage of its small size, high local cell density, and excellent electron exchange, this microfiber-like biohydrogel-based sensing system reached a linear calibration curve (R2 = 0.999) ranging from 1 nM to 10 mM. The limit of detection obtained was 0.60 nM, which was over 1300 times lower than a traditional biosensor for fumarate detection in 0.2 µL microdroplets. This work opened a new dimension for miniature whole-cell electrochemical sensing system design, which provided the possibility for bioelectrochemical detection in small volumes or three-dimensional local detection at high spatial resolutions.


Assuntos
Técnicas Biossensoriais , Grafite , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Bactérias , Fumaratos , Condutividade Elétrica , Limite de Detecção
19.
Oxid Med Cell Longev ; 2022: 8296043, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36439692

RESUMO

Background: Myopia is a chronic ocular disease, emerging as the most common type of refractive error. This study intends to preliminarily explore the roles of protein S-nitrosylation of nitric oxide (NO) in the regulation of myopia by detecting the expression of neuronal nitric oxide synthase (nNOS) and downstream S-nitrosylation, using the animal model of lens-induced myopia (LIM) in mice. Methods: The 3-week-old C57BL/6 J mice were divided into three groups: group I, lens-induced 0-week group (take eyeballs at the age of 3 weeks); group II, self-control eyes of experimental group (take eyeballs at the age of 7 weeks); and group III, lens-induced 4-week group (take eyeballs at the age of 7 weeks). The diopter and axial length of each group were measured by streak retinoscopes and optical coherence tomography (OCT) before and after model establishment. The protein expressions and locations of nNOS and S-nitrosylated proteins (PSNOs) were measured by western blot and immunofluorescence staining. Site-specific proteomic for protein S-nitrolysation was used to detect the existence and location of S-nitrosylation proteins in the retina of myopic and nonmyopic mice. The Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and motif enrichment analyses were performed. The differential sites were analyzed by GO, KEGG, and motif. Irreversible biotinylation procedure combined with protein purification and western blot was used to detect the protein expression of α-enolase (ENO1), a key player in the hypoxia-related signal pathway. Results: The expressions of nNOS and PSNOs were significantly lower in the retina of experimental eyes than that in self-control eyes and 3-week-old baseline group. A total of 595 S-nitrosylated proteins, 709 S-nitrosylated peptides, and 708 S-nitrosylated sites were identified by site-specific S-nitrolysation proteomics in the retina of myopic and control eyes. A total of 19 differentiation loci were screened, of which 13 sites were downregulated and 6 sites were upregulated in experimental eyes compared with the self-control group. Specifically, the expression of SNO-ENO1 was significantly lower in the retina of experimental eyes than that in self-control eyes and 3-week-old baseline group. Conclusion: LIM induces the decrease of nNOS and PSNO protein levels in the retina of myopic mice. NO-mediated nonclassical protein S-nitrosylation modification may play an important role in the regulation of lens-induced myopia. ENO1 may be a key factor in the regulation of S-nitrosylation modification of myopia.


Assuntos
Miopia , Óxido Nítrico , Camundongos , Animais , Óxido Nítrico/metabolismo , Proteômica , Camundongos Endogâmicos C57BL , Miopia/metabolismo , Retina/metabolismo
20.
Front Psychiatry ; 13: 1022036, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36440401

RESUMO

Background: Emotional disturbance is an important risk factor of suicidal behaviors. To ensure speech emotion recognition (SER), a novel technique to evaluate emotional characteristics of speech, precision in labeling emotional words is a prerequisite. Currently, a list of suicide-related emotional word is absent. The aims of this study were to establish an Emotional Words List for Suicidal Risk Assessment (EWLSRA) and test the reliability and validity of the list in a suicide-related SER task. Methods: Suicide-related emotion words were nominated and discussed by 10 suicide prevention professionals. Sixty-five tape-recordings of calls to a large psychological support hotline in China were selected to test psychometric characteristics of the EWLSRA. Results: The results shows that the EWLSRA consists of 11 emotion words which were highly associated with suicide risk scores and suicide attempts. Results of exploratory factor analysis support one-factor model of this list. The Fleiss' Kappa value of 0.42 indicated good inter-rater reliability of the list. In terms of criteria validities, indices of despair (Spearman ρ = 0.54, P < 0.001), sadness (ρ = 0.37, P = 0.006), helplessness (ρ = 0.45, P = 0.001), and numbness (ρ = 0.35, P = 0.009) were significantly associated with suicidal risk scores. The index of the emotional word of numbness in callers with suicide attempt during the 12-month follow-up was significantly higher than that in callers without suicide attempt during the follow-up (P = 0.049). Conclusion: This study demonstrated that the EWLSRA has adequate psychometric performance in identifying suicide-related emotional words of recording of hotline callers to a national wide suicide prevention line. This list can be useful for SER in future studies on suicide prevention.

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