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1.
Gastroenterology ; 167(3): 591-603.e9, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38583724

RESUMEN

BACKGROUND & AIMS: Benign ulcerative colorectal diseases (UCDs) such as ulcerative colitis, Crohn's disease, ischemic colitis, and intestinal tuberculosis share similar phenotypes with different etiologies and treatment strategies. To accurately diagnose closely related diseases like UCDs, we hypothesize that contextual learning is critical in enhancing the ability of the artificial intelligence models to differentiate the subtle differences in lesions amidst the vastly divergent spatial contexts. METHODS: White-light colonoscopy datasets of patients with confirmed UCDs and healthy controls were retrospectively collected. We developed a Multiclass Contextual Classification (MCC) model that can differentiate among the mentioned UCDs and healthy controls by incorporating the tissue object contexts surrounding the individual lesion region in a scene and spatial information from other endoscopic frames (video-level) into a unified framework. Internal and external datasets were used to validate the model's performance. RESULTS: Training datasets included 762 patients, and the internal and external testing cohorts included 257 patients and 293 patients, respectively. Our MCC model provided a rapid reference diagnosis on internal test sets with a high averaged area under the receiver operating characteristic curve (image-level: 0.950 and video-level: 0.973) and balanced accuracy (image-level: 76.1% and video-level: 80.8%), which was superior to junior endoscopists (accuracy: 71.8%, P < .0001) and similar to experts (accuracy: 79.7%, P = .732). The MCC model achieved an area under the receiver operating characteristic curve of 0.988 and balanced accuracy of 85.8% using external testing datasets. CONCLUSIONS: These results enable this model to fit in the routine endoscopic workflow, and the contextual framework to be adopted for diagnosing other closely related diseases.


Asunto(s)
Inteligencia Artificial , Colitis Ulcerosa , Colonoscopía , Humanos , Colitis Ulcerosa/diagnóstico , Estudios Retrospectivos , Femenino , Masculino , Persona de Mediana Edad , Adulto , Interpretación de Imagen Asistida por Computador/métodos , Curva ROC , Anciano , Reproducibilidad de los Resultados , Colon/patología , Colon/diagnóstico por imagen , Valor Predictivo de las Pruebas , Diagnóstico Diferencial , Grabación en Video , Aprendizaje Automático , Estudios de Casos y Controles
2.
Opt Lett ; 49(12): 3400-3403, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38875631

RESUMEN

The strong coupling of epsilon-near-zero materials with nanoantennas has demonstrated enhanced nonlinear optical responses, yet practical challenges persist. Here, we propose an alternative: an ultrathin metasurface featuring broadband response with a weakly dispersive nonlinear index, achieved through a simple implementation. Our metasurface, comprising a disordered gold nanorod array on indium tin oxide, exhibits polarization-independent behavior and a large average nonlinear refractive index of 5 cm2/GW across a broad wavelength range (1000-1300 nm). Enhanced performance is attributed to the weak coupling between gold nanorods and indium tin oxide, offering a cost-effective method for nonlinear optical metasurfaces and a flexible design in nanophotonic applications.

3.
Nicotine Tob Res ; 26(2): 126-134, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-37718628

RESUMEN

INTRODUCTION: The increasing popularity of electronic cigarettes (e-cigarettes) has led to the emergence of public health concerns, particularly among the youth. As a major producer and exporter of e-cigarettes, China has faced public health challenges in regulating the unregulated e-cigarette industry. AIMS AND METHODS: This study aims to evaluate the regulatory development of e-cigarettes in China. We searched and obtained national policy documents related to e-cigarettes and subnational smoke-free laws from LexisNexis on August 2, 2023, which were enacted between January 1, 2023 and July 31, 2023. We used 99 policy documents for the final analysis, specifically 68 national policy documents on e-cigarettes and 31 subnational smoke-free laws. We chronologically reviewed these policy documents in full text and summarized them on the basis of their content and the requirements of the World Health Organization Framework Convention on Tobacco Control (WHO FCTC). RESULTS: Chinese policymakers established the current regulatory framework for e-cigarettes by amending, enacting, and enforcing laws and regulations. E-cigarettes are categorized as tobacco products, and the State Tobacco Monopoly Administration regulates the e-cigarette industry. The Chinese authorities prioritize youth prevention in strengthening the regulation on e-cigarettes. China adopts various tobacco control measures for e-cigarettes and cigarettes. CONCLUSIONS: China gained certain degrees of progress on tobacco control by regulating e-cigarettes and adopting measures required by the WHO FCTC. However, tobacco monopoly hinders the full realization of tobacco control goals, which necessitates the National Health Commission to assume its responsibility for the complete implementation of the WHO FCTC. IMPLICATIONS: This study presents a critical review of the development of e-cigarette regulation in China by reviewing relevant policy documents and analyzing tobacco control measures. It recognizes the degrees of progress of tobacco control measures and highlights tobacco monopoly as a significant hindrance of the full implementation of the WHO FCTC. Furthermore, empirical studies are required on the enforcement of tobacco control measures in China.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Productos de Tabaco , Adolescente , Humanos , Prevención del Hábito de Fumar , Control del Tabaco , China/epidemiología
4.
Biotechnol Appl Biochem ; 71(1): 193-201, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37904286

RESUMEN

In this study, an electrochemical biosensor was constructed for the detection of fibrin, specifically by a simple two-step approach, with a novel artificial enzyme (Tetrazyme) based on the DNA tetrahedral framework as signal probe. The multichannel screen-printed electrode with the activated surface cannot only remove some biological impurities, but also serve as a carrier to immobilize a large number of antigen proteins. The DNA tetrahedral nanostructure was employed to ensure the high sensitivity of the probe for biological analysis. The hemin was chimeric into the G-quadruplex to constitute the complex with peroxidase catalytic activity (hemin/G4-DNAzyme), subsequently, Tetrazyme was formed through combining of this complex and DNA tetrahedral nucleic acid framework. The artificial enzyme signal probe formed by the covalent combination of the homing peptide (Cys-Arg-Glu-Lys-Ala, CREKA), which is the aptamer of fibrin and the new artificial enzyme is fixed on the surface of the multichannel carbon electrode by CREKA-specific recognition, so as to realize the sensitive detection of fibrin. The feasibility of sensing platform was validated by cyclic voltammetry (CV) and amperometric i-t curve (IT) methods. Effects of Tetrazyme concentration, CREKA concentrations and hybridization time on the sensor were explored. Under the best optimal conditions of 0.6 µmol/L Tetrazyme, 80 µmol/L CREKA, and 2.5 h reaction time, the immunosensor had two linear detection ranges, 10-40 nmol/L, with linear regression equation Y = 0.01487X - 0.011 (R2 = 0.992), and 50-100 nmol/L, with linear regression equation Y = 0.00137X + 0.6405 (R2 = 0.998), the detection limit was 9.4 nmol/L, S/N ≥ 3. The biosensor could provide a new method with great potential for the detection of fibrin with good selectivity, stability, and reproducibility.


Asunto(s)
Técnicas Biosensibles , Técnicas Biosensibles/métodos , Hemina/química , Fibrina , Reproducibilidad de los Resultados , Límite de Detección , Inmunoensayo , ADN/química , Técnicas Electroquímicas/métodos
5.
J Transl Med ; 21(1): 496, 2023 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-37488572

RESUMEN

BACKGROUND: Substantial studies have demonstrated that oxidative stress placenta and endothelial injury are considered to inextricably critical events in the pathogenesis of preeclampsia (PE). Systemic inflammatory response and endothelial dysfunction are induced by the circulating factors released from oxidative stress placentae. As a novel biomarker of oxidative stress, advanced oxidation protein products (AOPPs) levels are strongly correlated with PE characteristics. Nevertheless, the molecular mechanism underlying the effect of factors is still largely unknown. METHODS: With the exponential knowledge on the importance of placenta-derived extracellular vesicles (pEVs), we carried out lncRNA transcriptome profiling on small EVs (sEVs) secreted from AOPPs-treated trophoblast cells and identified upregulated lncRNA TDRKH-AS1 as a potentially causative factor for PE. We isolated and characterized sEVs from plasma and trophoblast cells by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA) and western blotting. The expression and correlation of lncRNA TDRKH-AS1 were evaluated using qRT-PCR in plasmatic sEVs and placentae from patients. Pregnant mice injected with TDRKH-AS1-riched trophoblast sEVs was performed to detect the TDRKH-AS1 function in vivo. To investigate the potential effect of sEVs-derived TDRKH-AS1 on endothelial function in vitro, transcriptome sequencing, scanning electron Microscopy (SEM), immunofluorescence, ELISA and western blotting were conducted in HUVECs. RNA pulldown, mass spectrometry, RNA immunoprecipitation (RIP), chromatin isolation by RNA purification (ChIRP) and coimmunoprecipitation (Co-IP) were used to reveal the latent mechanism of TDRKH-AS1 on endothelial injury. RESULTS: The expression level of TDRKH-AS1 was significantly increased in plasmatic sEVs and placentae from patients, and elevated TDRKH-AS1 in plasmatic sEVs was positively correlated with clinical severity of the patients. Moreover, pregnant mice injected with TDRKH-AS1-riched trophoblast sEVs exhibited a hallmark feature of PE with increased blood pressure and systemic inflammatory responses. Pyroptosis, an inflammatory form of programmed cell death, is involved in the development of PE. Indeed, our in vitro study indicated that sEVs-derived TDRKH-AS1 secreted from AOPPs-induced trophoblast elevated DDIT4 expression levels to trigger inflammatory response of pyroptosis in endothelial cells through interacting with PDIA4. CONCLUSIONS: Herein, results in the present study supported that TDRKH-AS1 in sEVs isolated from oxidative stress trophoblast may be implicated in the pathogenesis of PE via inducing pyroptosis and aggravating endothelial dysfunction.


Asunto(s)
Vesículas Extracelulares , Preeclampsia , ARN Largo no Codificante , Femenino , Embarazo , Humanos , Animales , Ratones , Células Endoteliales , Piroptosis , Productos Avanzados de Oxidación de Proteínas , Trofoblastos , Proteínas de Unión al ARN , Factores de Transcripción , Proteína Disulfuro Isomerasas
6.
J Eur Acad Dermatol Venereol ; 37(12): 2583-2588, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37591629

RESUMEN

BACKGROUND: Wide local excision (WLE) of the nail unit is widely used in treating in situ and minimally invasive malignant subungual tumours. After WLE, diverse reconstruction methods have been reported. However, the best repair method has yet to be determined. OBJECTIVE: To compare the repair effects and postoperative morbidity of secondary intention healing (SIH), artificial dermis grafting combined with secondary intention healing (ADGSIH) and full-thickness skin grafting (FSG) after WLE of the nail unit. METHODS: We retrospectively reviewed 21 patients who underwent WLE of the nail unit. The re-epithelializing time, functional and cosmetic outcomes, postoperative complications and patients' satisfaction were assessed from the follow-up records. RESULTS: The FSG group showed more rapid healing and better functional and cosmetic outcomes than the SIH and ADGSIH groups. The ADGSIH and FSG groups showed significant pain relief compared to the SIH group. No serious early and late postoperative complications were reported. The median follow-up period was 26 months, and no recurrence was observed. All patients were satisfied with the treatment. CONCLUSIONS: FSG after the WLE of the nail unit is a therapeutic option with convenient application, significant pain relief, rapid recovery and satisfying functional and cosmetic outcomes.


Asunto(s)
Neoplasias Cutáneas , Humanos , Neoplasias Cutáneas/cirugía , Neoplasias Cutáneas/patología , Estudios Retrospectivos , Uñas/cirugía , Uñas/patología , Complicaciones Posoperatorias/epidemiología , Dolor
7.
Bioprocess Biosyst Eng ; 45(1): 107-115, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34601618

RESUMEN

Polyunsaturated fatty acid (PUFA) synthase is a special and effective enzyme for PUFA synthesis, and dehydratase (DH) domain played a crucial role in it. In this work, we compared four different DH domains from different strains (Schizochytrium sp. HX-308 and Shewanella sp. BR-2) and different gene clusters. First bioinformatics analysis showed that DH1, 2 and DH3 were similar to FabA and PKS-DH, respectively, and all of them got a hot-dog structure. Second, four DH domains were expressed in Escherichia coli that increased biomass. Especially, Schi-DH1,2 presented the highest dry cell weight of 2.3 g/L which was 1.62 times of that of control. Fatty acids profile analysis showed that DH1,2 could enhance the percentage of unsaturated fatty acids, especially DH1,2 from Schizochytrium sp., while DH3 benefited for the saturated fatty acid biosynthesis. Furthermore, five kinds of fatty acids were added to the medium to study the substrate preferences. Results revealed that DH1,2 domain preferred to acting on C16:0, while DH3 domain trended acting on C14:0 and C15:0, which illustrated DH from different clusters do have specific substrate preference. Besides, DH expression could save the cell growth inhibition by mid-chain fatty acids. This study provided more information about the catalysis mechanism of polyunsaturated fatty acid synthase and might promote the modification study based on this enzyme.


Asunto(s)
Ácidos Grasos/biosíntesis , Hidroliasas/metabolismo , Shewanella/química , Estramenopilos/química
8.
Sensors (Basel) ; 22(19)2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-36236777

RESUMEN

As the main power source of new energy electric vehicles, the accurate estimation of State of Charge (SOC) of Li-ion batteries is of great significance for accurately estimating the vehicle's driving range, prolonging the battery life, and ensuring the maximum efficiency of the whole battery pack. In this paper, the ternary Li-ion battery is taken as the research object, and the Dual Polarization (DP) equivalent circuit model with temperature-varying parameters is established. The parameters of the Li-ion battery model at ambient temperature are identified by the forgetting factor least square method. Based on the state space equation of power battery SOC, an adaptive Sliding Mode Observer is used to study the estimation of the State of Charge of the power battery. The SOC estimation results are fully verified at low temperature (0 °C), normal temperature (25 °C), and high temperature (50 °C). The simulation results of the Urban Dynamometer Driving Schedule (UDDS) show that the SOC error estimated at low temperature and high temperature is within 2%, and the SOC error estimated at normal temperature is less than 1%, The algorithm has the advantages of accurate estimation, fast convergence, and strong robustness.

9.
Int J Mol Sci ; 21(21)2020 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-33171780

RESUMEN

Sclerotinia sclerotiorum (Ss) is a devastating fungal pathogen that causes Sclerotinia stem rot in rapeseed (Brassica napus), and is also detrimental to mulberry and many other crops. A wild mulberry germplasm, Morus laevigata, showed high resistance to Ss, but the molecular basis for the resistance is largely unknown. Here, the transcriptome response characteristics of M. laevigata to Ss infection were revealed by RNA-seq. A total of 833 differentially expressed genes (DEGs) were detected after the Ss inoculation in the leaf of M. laevigata. After the GO terms and KEGG pathways enrichment analyses, 42 resistance-related genes were selected as core candidates from the upregulated DEGs. Their expression patterns were detected in the roots, stems, leaves, flowers, and fruits of M. laevigata. Most of them (30/42) were specifically or mainly expressed in flowers, which was consistent with the fact that Ss mainly infects plants through floral organs, and indicated that Ss-resistance genes could be induced by pathogen inoculation on ectopic organs. After the Ss inoculation, these candidate genes were also induced in the two susceptible varieties of mulberry, but the responses of most of them were much slower with lower extents. Based on the expression patterns and functional annotation of the 42 candidate genes, we cloned the full-length gDNA and cDNA sequences of the Ss-inducible chitinase gene set (MlChi family). Phylogenetic tree construction, protein interaction network prediction, and gene expression analysis revealed their special roles in response to Ss infection. In prokaryotic expression, their protein products were all in the form of an inclusion body. Our results will help in the understanding of the molecular basis of Ss-resistance in M. laevigata, and the isolated MlChi genes are candidates for the improvement in plant Ss-resistance via biotechnology.


Asunto(s)
Ascomicetos/patogenicidad , Quitinasas/genética , Morus/genética , Ascomicetos/genética , Ascomicetos/metabolismo , Ascomicetos/fisiología , Quitinasas/metabolismo , Resistencia a la Enfermedad/genética , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica de las Plantas/genética , Morus/metabolismo , Filogenia , Enfermedades de las Plantas/microbiología , Hojas de la Planta/metabolismo , Proteínas de Plantas/metabolismo , Transcriptoma/genética
10.
Zhongguo Zhong Yao Za Zhi ; 45(16): 3900-3907, 2020 Aug.
Artículo en Zh | MEDLINE | ID: mdl-32893587

RESUMEN

A highly sensitive monoclonal antibody against aflatoxin B_1(AFB_1) was prepared and an indirect competition enzyme-linked immunosorbent assay(ic-ELISA) was established based on the antibody which was used for high-throughput and rapid screening of AFB_1 contamination in Chinese herbal medicines to ensure the safety of medication. In this study, the structure of AFB_1 was modified by improved oxime method, and the carrier protein was coupled by EDC-NHS method to obtain the complete antigen of AFB_1, which was more convenient and environmental friendly. The Balb/c female mice were immunized using increasing the immunization dose and various ways of injection, and finally the AFB_1 monoclonal antibody was prepared. The AFB_1 monoclonal antibody belongs to IgG_(2 b) immunoglobulin by identifying its immunological characteristics, and its sensitivity(IC_(50)) can reach 0.15 µg·L~(-1), and the affi-nity is 2.81×10~8 L·mol~(-1). The cross-reaction rates of AFB_2, AFG_1, and AFG_2 were 35.07%, 8.75%, and 1.15%, respectively, and there was almost no cross-reactivity with other mycotoxins. Based on the high sensitivity and specificity of the antibody, an ic-ELISA method was established and applied to the determination of AFB_1 contamination in Ziziphi Spinosae Semen. According to the matrix matching standard curve, the linear concentration range for AFB_1 was 0.05-0.58 µg·L~(-1)(R~2=0.992), the recoveries were 88.00%-119.0%, and the detection limit was 1.69 µg·kg~(-1). The AFB_1 in 33 batches of Ziziphi Spinosae Semen samples was determined by ic-ELISA, and the contamination level was 3.62-206.58 µg·kg~(-1). The linear correlation coefficient between the detection results of ic-ELISA and UHPLC-MS/MS was 0.996, and there were no false positive and false negative cases. It indicates that the established ic-ELISA is accurate and reliable, and could provide a simple and effective technique for fast screening of AFB_1 contamination in Ziziphi Spinosae Semen, and also could be considered as the reference for the detection and monitoring of AFB_1 contamination in other Chinese herbal medicines.


Asunto(s)
Aflatoxina B1/análisis , Semen/química , Animales , Anticuerpos Monoclonales , Contaminación de Medicamentos , Ensayo de Inmunoadsorción Enzimática , Femenino , Ratones , Espectrometría de Masas en Tándem
12.
Appl Microbiol Biotechnol ; 103(8): 3239-3248, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30877356

RESUMEN

Microalgae are arguably the most abundant single-celled eukaryotes and are widely distributed in oceans and freshwater lakes. Moreover, microalgae are widely used in biotechnology to produce bioenergy and high-value products such as polyunsaturated fatty acids (PUFAs), bioactive peptides, proteins, antioxidants and so on. In general, genetic editing techniques were adapted to increase the production of microalgal metabolites. The main genome editing tools available today include zinc finger nucleases (ZFNs), transcriptional activator-like effector nucleases (TALENs), and the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas nuclease system. Due to its high genome editing efficiency, the CRISPR/Cas system is emerging as the most important genome editing method. In this review, we summarized the available literature on the application of CRISPR/Cas in microalgal genetic engineering, including transformation methods, strategies for the expression of Cas9 and sgRNA, the CRISPR/Cas9-mediated gene knock-in/knock-out strategies, and CRISPR interference expression modification strategies.


Asunto(s)
Sistemas CRISPR-Cas/genética , Edición Génica , Microalgas/genética , Proteína 9 Asociada a CRISPR/genética , Regulación de la Expresión Génica , Marcación de Gen , Ingeniería Genética , ARN Guía de Kinetoplastida/genética , Transformación Genética
13.
J Sports Sci ; 37(18): 2152-2158, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31138012

RESUMEN

This study aimed to explore the plantar loading variables between habitual rearfoot strike (RFS) and non-rearfoot strike (NRFS) during running. 78 healthy males participated in this study (41 RFS, 37 NRFS). In-shoe pressure sensors were used to measure plantar loading while the participants were running on a 15 m indoor runway with their preferred foot strike pattern (FSP) at 12.0 ± 5% km/h. Results indicate that force and pressure parameters were much higher in the rearfoot and midfoot regions during RFS running and relatively greater in forefoot region during NRFS running. However, compared with NRFS running, the contact area, maximum force and force-time-integrals during RFS running on total foot were 21.44% (P < 0.001, ES = 2.29), 13.99% (P = 0.006, ES = 0.64) and 21.27% (P < 0.001, ES = 0.85) higher, respectively. Total foot peak pressure and pressure-time-integral between two FSPs were similar. Higher loads in the rearfoot region may transmit to the knee joint and result in patellofemoral joint injuries. NRFS runners' higher loads in forefoot seem to be ralated to metatarsal stress fractures and compensatory damage to the Achilles tendon. Therefore, runners should choose proper FSPs according to their unique physical conditions.


Asunto(s)
Pie/fisiología , Marcha , Carrera/fisiología , Adulto , Fenómenos Biomecánicos , Humanos , Masculino , Presión , Estrés Mecánico , Soporte de Peso , Adulto Joven
14.
Zhongguo Zhong Yao Za Zhi ; 44(23): 5072-5077, 2019 Dec.
Artículo en Zh | MEDLINE | ID: mdl-32237339

RESUMEN

An indirect competitive enzyme-linked immunosorbent assay( ic-ELISA) was developed for the rapid detection of ochratoxin A( OTA) in nutmeg( Myristicae Semen),ginger( Zingiberis Rhizoma) and turmeric( Curcumae Longae Rhizoma). The matrix matching standard curve was used instead of the standard curve of sample diluent,and the sample extract and sample diluent were optimized. The sensitivity( IC_(50)) of this method for OTA in nutmeg,ginger and turmeric were determined as 0. 146,0. 157 and 0. 153 ng·m L~(-1),respectively and the limits of detection( LODs) were 0. 040,0. 032 and 0. 031 ng·m L~(-1),respectively. The recovery of samples ranged from 75. 99% to 122. 3%,with RSD<10%. Two positive samples for nutmeg and one positive sample for turmeric occurred in 50 samples,and the highest OTA contamination value was 1 167. 8 µg·kg~(-1). The results were further confirmed by LC-MS/MS. It shows that the developed ic-ELISA method is simple,rapid and sensitive,and can be applied for rapid and high-throughput screening of OTA in nutmeg,ginger and turmeric,as well as some other CHMs.


Asunto(s)
Contaminación de Medicamentos , Medicamentos Herbarios Chinos/análisis , Ensayo de Inmunoadsorción Enzimática , Ocratoxinas/análisis , Cromatografía Liquida , Ensayos Analíticos de Alto Rendimiento , Espectrometría de Masas en Tándem
15.
Protein Expr Purif ; 151: 30-37, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29894803

RESUMEN

1-Deoxynojirimycin (DNJ) is the main bioactive compound of Morus alba L.. DNJ has pharmacological effects, including blood sugar level regulation and antiviral activity. In this study, the mulberry lysine decarboxylase gene (MaLDC), which is involved in the biosynthesis of DNJ alkaloids, was cloned, expressed, and functionally verified. MaLDC was induced and expressed in Escherichia coli BL21 (DE3). The recombinant soluble MaLDC protein had a relative molecular mass of 24.0 kDa. The protein was purified by Ni-NTA separation. The results showed that MaLDC protein could catalyze lysine decarboxylation to produce cadaverine. The Km and Vmax values were 19.2 µM and 3.31 µM/min, respectively. Quantitative real-time reverse transcription polymerase chain reaction revealed that MaLDC expression was positively correlated with DNJ content (P < 0.001), indicating that the MaLDC could encode a functional protein involved in the biosynthesis of DNJ alkaloid in mulberry. Our results provided a foundation for further studies of the enzymatic properties of LDC and established a basis for the analysis of key enzymes involved in the biosynthetic pathway of mulberry DNJ alkaloid.


Asunto(s)
Carboxiliasas/biosíntesis , Morus/enzimología , Proteínas de Plantas/biosíntesis , 1-Desoxinojirimicina/metabolismo , Cadaverina/metabolismo , Carboxiliasas/química , Clonación Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Hojas de la Planta/enzimología , Proteínas de Plantas/química , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química
16.
JMIR Mhealth Uhealth ; 12: e55061, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38904994

RESUMEN

BACKGROUND: Hospital apps are increasingly being adopted in many countries, especially since the start of the COVID-19 pandemic. Web-based hospitals can provide valuable medical services and enhanced accessibility. However, increasing concerns about personal information (PI) and strict legal compliance requirements necessitate privacy assessments for these platforms. Guided by the theory of contextual integrity, this study investigates the regulatory compliance of privacy policies for internet hospital apps in the mainland of China. OBJECTIVE: In this paper, we aim to evaluate the regulatory compliance of privacy policies of internet hospital apps in the mainland of China and offer recommendations for improvement. METHODS: We obtained 59 internet hospital apps on November 7, 2023, and reviewed 52 privacy policies available between November 8 and 23, 2023. We developed a 3-level indicator scale based on the information processing activities, as stipulated in relevant regulations. The scale comprised 7 level-1 indicators, 26 level-2 indicators, and 70 level-3 indicators. RESULTS: The mean compliance score of the 52 assessed apps was 73/100 (SD 22.4%), revealing a varied spectrum of compliance. Sensitive PI protection compliance (mean 73.9%, SD 24.2%) lagged behind general PI protection (mean 90.4%, SD 14.7%), with only 12 apps requiring separate consent for processing sensitive PI (mean 73.9%, SD 24.2%). Although most apps (n=41, 79%) committed to supervising subcontractors, only a quarter (n=13, 25%) required users' explicit consent for subcontracting activities. Concerning PI storage security (mean 71.2%, SD 29.3%) and incident management (mean 71.8%, SD 36.6%), half of the assessed apps (n=27, 52%) committed to bear corresponding legal responsibility, whereas fewer than half (n=24, 46%) specified the security level obtained. Most privacy policies stated the PI retention period (n=40, 77%) and instances of PI deletion or anonymization (n=41, 79%), but fewer (n=20, 38.5%) committed to prompt third-party PI deletion. Most apps delineated various individual rights, but only a fraction addressed the rights to obtain copies (n=22, 42%) or to refuse advertisement based on automated decision-making (n=13, 25%). Significant deficiencies remained in regular compliance audits (mean 11.5%, SD 37.8%), impact assessments (mean 13.5%, SD 15.2%), and PI officer disclosure (mean 48.1%, SD 49.3%). CONCLUSIONS: Our analysis revealed both strengths and significant shortcomings in the compliance of internet hospital apps' privacy policies with relevant regulations. As China continues to implement internet hospital apps, it should ensure the informed consent of users for PI processing activities, enhance compliance levels of relevant privacy policies, and fortify PI protection enforcement across the information processing stages.


Asunto(s)
Aplicaciones Móviles , China , Humanos , Aplicaciones Móviles/normas , Aplicaciones Móviles/estadística & datos numéricos , Aplicaciones Móviles/legislación & jurisprudencia , Seguridad Computacional/normas , Seguridad Computacional/legislación & jurisprudencia , COVID-19/prevención & control , COVID-19/epidemiología , Confidencialidad/normas , Confidencialidad/legislación & jurisprudencia , Internet , Pandemias/prevención & control
17.
Heliyon ; 10(11): e31363, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38882366

RESUMEN

The frequent occurrence of extreme heat events has notably affected human's living environment, and a considerable number of studies have reported that green space is an efficient measure by investigating the correlation between green space and land surface temperature (LST). However, spatiotemporal effects of green space on LST still remain unclear. In this study, green space patterns (e.g., core, islet, perforation, edge, loop, bridge, and branch) were identified through morphological spatial pattern analysis (MSPA). Moreover, the effects of green space pattern on LST in three periods were investigated through three kinds of models. As indicated by the results: (1) the geographically and temporally weighted regression model exhibited the optimal performance compared with other two models. (2) in general, the core, the edge, the bridge, and the branch significantly contributed to cooling, and the islet hindered cooling. However, the perforation and the loop exerted significant dual nature effects with the similar quantity of the negative and positive coefficients, showing relatively complex impact mechanism. (3) the intensity of the effect of the respective MSPA class varied across the study area. The core had the most substantial effect, which distributed in the south and middle corners. (4) the result suggested that a neighborhood scale in China, which was 960 m in this study, served as a basic unit in green space management. The spatiotemporal non-stationarity of the effects of green space morphological patterns on LST provided important insights into urban thermal environment improvement through urban green space planning and design.

18.
ACS Synth Biol ; 13(8): 2470-2479, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39096298

RESUMEN

Membrane lipid chemistry is remarkably different in archaea compared with bacteria and eukaryotes. In the evolutionary context, this is also termed the lipid divide and is reflected by distinct biosynthetic pathways. Contemporary organisms have almost without exception only one type of membrane lipid. During early membrane evolution, mixed membrane stages likely occurred, and it was hypothesized that the instability of such mixtures was the driving force for the lipid divide. To examine the compatibility between archaeal and bacterial lipids, the bacterium Escherichia coli has been engineered to contain both types of lipids with varying success. Only limited production of archaeal lipid archaetidylethanolamine was achieved. Here, we substantially increased its production in E. coli by overexpression of an archaeal phosphatidylserine synthase needed for ethanolamine headgroup attachment. Furthermore, we introduced a synthetic isoprenoid utilization pathway to increase the supply of isopentenyl-diphosphate and dimethylallyl diphosphate. This improved archaeal lipid production substantially. The archaeal phospholipids also served as a substrate for the E. coli cardiolipin synthase, resulting in archaeal and novel hybrid archaeal/bacterial cardiolipin species not seen in living organisms before. Growth of the E. coli strain with the mixed membrane shows an enhanced sensitivity to the inhibitor of fatty acid biosynthesis, cerulenin, indicating a critical dependence of the engineered E. coli strain on its native phospholipids.


Asunto(s)
Escherichia coli , Escherichia coli/metabolismo , Escherichia coli/genética , Ingeniería Metabólica/métodos , Archaea/metabolismo , Archaea/genética , Lípidos de la Membrana/metabolismo , Lípidos de la Membrana/biosíntesis , Terpenos/metabolismo , Compuestos Organofosforados/metabolismo , Hemiterpenos/metabolismo , Hemiterpenos/biosíntesis , Fosfolípidos/biosíntesis , Fosfolípidos/metabolismo , Cardiolipinas/metabolismo , Cardiolipinas/biosíntesis , CDPdiacilglicerol-Serina O-Fosfatidiltransferasa/metabolismo , CDPdiacilglicerol-Serina O-Fosfatidiltransferasa/genética , Proteínas de la Membrana , Transferasas (Grupos de Otros Fosfatos Sustitutos)
19.
MethodsX ; 13: 102862, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39171192

RESUMEN

Sustainable intensification (SI) of agriculture can produce more food to meet the demand of a growing population while considering ecosystem health. The current SI estimation framework ignores the complex coupling between input and output intensity of arable land. A method for coupled analysis of arable land input intensity and output intensity based on sliding windows is proposed. By calculating the correlation coefficient and partial correlation coefficient between input intensity and output intensity in different value ranges as the order parameter, the phase transition and the influence process of input intensity on output intensity can be explained. Meanwhile, a python-based framework is developed. An application of the method was made to reveal the interaction process between annual provincial input intensity and output intensity in mainland China. Researchers in many fields may benefit from the method by obtaining a fast way to analysis the coupling relationship between driving and dependent variables in complex systems.•New method for SI estimation is presented.•The order parameter of the coupling relationship between input and output intensity is calculated based on sliding windows.•Analysis of coupling relationships between driving and dependent variables in complex systems.

20.
Bioelectrochemistry ; 156: 108627, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38142545

RESUMEN

The level of folate receptor (FR) has become one of the independent factors for measuring human tumor diseases. The precise quantification of FR is helpful for the early diagnosis and subsequent treatment of tumors. The modification of electrodes is a key issue in ensuring and enhancing the electrochemical biosensing ability. In this study, we in-situ synthesized a nanocomposite material with excellent conductivity and stability by grafting first-generation poly(amidoamine) dendrimers onto the MXene (Ti3C2TX) as the immobilized matrix (PAMAM@MXene). An electrochemical sensor was developed for FR monitor by loading the PAMAM@MXene on screen-printed carbon electrodes (SPCEs). Scanning electron microscopy (SEM) supported the effective synthesis of PAMAM@MXene. Under optimal conditions, the prepared sensor achieved the quantification of FR with a wide range of concentrations from 10 ng/mL to 1000 ng/mL with a detection limit (LOD) of 5.6 ng/mL. It also exhibited satisfactory selectivity, reproducibility, and stability, which provided the possibility for expanding new pathways in the detection of clinical FR.


Asunto(s)
Técnicas Biosensibles , Neoplasias , Nitritos , Elementos de Transición , Humanos , Reproducibilidad de los Resultados , Técnicas Electroquímicas , Electrodos , Ácido Fólico
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