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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.â¢New method for SI estimation is presented.â¢The order parameter of the coupling relationship between input and output intensity is calculated based on sliding windows.â¢Analysis of coupling relationships between driving and dependent variables in complex systems.
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Background Nail unit squamous cell carcinoma (nSCC) is a malignant subungual tumour. Although it has a low risk of metastasis and mortality, the tumour has a significant local recurrence rate. There is insufficient data to determine whether functional surgery is less effective than amputation for nSCC that does not involve the bone. Objectives We aimed to investigate existing data on the outcomes of functional surgery and amputation for nSCC without bone invasion. Materials and Methods We carried out an extensive search in PubMed, Embase, Cochrane Library, Web of Science, and Scopus for appropriate English-language academic papers, starting with the creation of individual resources until February 23, 2023. The main outcome was local recurrence. Initially, 2191 studies related to nSCC were selected. Information from every research study was retrieved and subdivided, comprising the year of publication, period, number of patients, age, gender distribution, tumour stage, type of intervention, number of recurrences, and follow-up period. Results Ten independent studies (319 lesions) were finally selected. Mohs micrographic surgery was the most reported surgical modality, followed by wide surgical excision and amputation. Local recurrence rates between Mohs micrographic surgery, wide surgical excision and amputation treatment were nearly identical. Other surgical methods included limited surgical excision, partial ablation, and limited excision until the clearing of margins, with recurrence rates up to 50%. Conclusions Given the functional impairment and psychological distress associated with phalanx amputation, functional surgery, including Mohs micrographic surgery and wide surgical excision , should be the preferred therapy for nSCC without bone involvement. Amputation should remain the preferred therapy for nSCC that involves the bone. Partial excision should be avoided. Further studies on whether Mohs micrographic surgery or wide surgical excision is a better option for nSCC not involving the bone are required.
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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.
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Escherichia coli , Escherichia coli/metabolismo , Escherichia coli/genética , Engenharia Metabólica/métodos , Archaea/metabolismo , Archaea/genética , Lipídeos de Membrana/metabolismo , Lipídeos de Membrana/biossíntese , Terpenos/metabolismo , Compostos Organofosforados/metabolismo , Hemiterpenos/metabolismo , Hemiterpenos/biossíntese , Fosfolipídeos/biossíntese , Fosfolipídeos/metabolismo , Cardiolipinas/metabolismo , Cardiolipinas/biossíntese , CDPdiacilglicerol-Serina O-Fosfatidiltransferase/metabolismo , CDPdiacilglicerol-Serina O-Fosfatidiltransferase/genética , Proteínas de Membrana , Transferases (Outros Grupos de Fosfato Substituídos)RESUMO
In contemporary society, the improper use of antibiotics leads to their persistent presence in the ecological environment. Due to the diverse physical and chemical properties of antibiotics, their spatial and temporal distribution in the environment varies. Moreover, antibiotics can stimulate the emergence of antibiotic resistance genes (ARGs), which complicates the monitoring and regulation of antibiotics and poses a significant threat to both aquatic and terrestrial environments. This study investigated the distribution of 15 antibiotics and 11 typical ARGs across four categories at 19 sites of drinking water sources in Wuhan, China. The findings revealed that the concentration of antibiotics during the dry season (nd~61,883 ng/L) was significantly higher compared to both the normal water season (nd~49,883 ng/L) and the wet season (nd~28,686 ng/L). Sulfamethoxazole (SMX), sulfamethoxazole (SMD), sulfadiazine (SD), and roxithromycin (RTM) were the predominant antibiotics in the target water environments. The study indicated that most of the antibiotics analyzed posed little to no risk to aquatic organisms. The primary ARGs detected in the surface water of the study area were sul1, qnrD, and tetO. Furthermore, some ARGs showed a negative correlation with their respective antibiotics. Additional research is necessary to evaluate the impact of these emerging pollutants (antibiotics and ARGs) on the safety of high-quality drinking water for residents in Wuhan City.
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A dressing patch made of radially oriented poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanofibers was successfully manufactured with a modified electrospinning strategy. The as-electrospun PHBV radially oriented nanofiber dressing patch exhibited uniform and bead-free nanofibrous morphology and innovative radially oriented arrangement, which was demonstrated to possess obviously improved mechanical property, increased surface hydrophilicity and enhanced biological properties compared to the PHBV nanofiber dressing patch control with traditionally randomly oriented pattern. Interestingly, it was found that the radially oriented pattern could induce the cell migration from the periphery to the center along the radially oriented nanofibers in a rapid manner. To further improve the biofunction of PHBV radially oriented nanofiber dressing patch, berberine (Beri, an isoquinoline alkaloid) with two different concentrations were encapsulated into PHBV nanofibers during electrospinning, which were found to present a sustained drug release behavior for nearly one month. Importantly, the addition of Beri could impart the dressing patch with excellent anti-inflammatory property by significantly inhibiting the secretion of pro-inflammatory factors of M1 macrophages, and also showed an additive influence on promoting the proliferation of human dermal fibroblasts (HDFs), as well as inhibiting the growth of E. coli, S. aureus and C. albicans, compared with the Beri-free dressing patch. In the animal studies, the electrospun PHBV radially oriented nanofiber dressing patch loading with high Beri content was found to obviously accelerate the healing process of diabetic mouse full-thickness skin wound with shortened healing time (100% wound closure rate after 18 days' treatment) and improved healing quality (improved collagen deposition, enhanced re-epithelialization and neovascularization and increased hair follicles). In all, this study reported an innovative therapeutic strategy integrating the excellent physical cues of electrospun PHBV radially oriented nanofiber dressing patch with the multiple biological cues of Beri for the effective treatment of hard-to-heal diabetic wounds.
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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 5â cm2/GW across a broad wavelength range (1000-1300â 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.
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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.
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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.
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Aplicativos Móveis , China , Humanos , Aplicativos Móveis/normas , Aplicativos Móveis/estatística & dados numéricos , Aplicativos Móveis/legislação & jurisprudência , Segurança Computacional/normas , Segurança Computacional/legislação & jurisprudência , COVID-19/prevenção & controle , COVID-19/epidemiologia , Confidencialidade/normas , Confidencialidade/legislação & jurisprudência , Internet , Pandemias/prevenção & controleRESUMO
Background: China has the highest number of new cancer cases and deaths globally. Due to particularly low scores in health care quality for cutaneous squamous cell carcinoma (cSCC), the country's cSCC burden requires greater awareness. Consequently, we aimed to evaluate and predict the trend of the cSCC burden globally and in China from 1990 to 2030. Methods: We retrieved data from the Global Burden of Disease 2019 study, which provided estimates of the incidence, mortality, prevalence, and disability-adjusted life years (DALYs) of cSCC from 1990 to 2019. We set up joint-point analyses and Bayesian age-period-cohort (BAPC) models to predict the disease burden of cSCC up to 2030. Results: In 2019, China reported age-standardised rates of cSCC prevalence, incidence, mortality, and DALYs of 2.54, 2.12, 0.88, and 16.76 per 100 000 population, respectively. The country's prevalence and incidence rates from 1990 to 2019 were lower than the global levels, but its mortality and DALY rates were higher. The age-standardised rates were higher for males, and the disease burden increased with each age group globally and in China. Moreover, the average annual percentage change showed all indicators were growing faster than the global levels. According to the BAPC model, there will be an upward trend in the prevalence and incidence globally and in China between 2020 and 2030, with a decrease in mortality and DALYs. Conclusions: We observed an upward trend in the cSCC burden over the past 30 years in China. Prevalence and incidence are expected to continue at a higher rate than the global average in the next decade, while mortality and DALYs are predicted to decrease. As the Chinese population ages, efforts toward managing and preventing cSCC should be targeted towards the elderly population.
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Carcinoma de Células Escamosas , Carga Global da Doença , Neoplasias Cutâneas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Teorema de Bayes , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/mortalidade , China/epidemiologia , Anos de Vida Ajustados por Deficiência , Previsões , Carga Global da Doença/tendências , Incidência , Prevalência , Anos de Vida Ajustados por Qualidade de Vida , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/mortalidadeRESUMO
Hidradenitis suppurativa (HS) is an inflammatory follicular dermatological condition that typically affects the intertriginous and anogenital regions of the apocrine gland-bearing skin. The management of this chronic and recurring disease necessitates a combination of lifestyle changes, medication, and surgical approaches to achieve the best possible outcomes. While medical treatments are recommended for this multimodal disease, surgical therapy, which is the gold standard of treatment for HS, has proven to be the most effective treatment because it provides long-lasting local disease control, reduces the recurrence of lesions, and ensures complete healing of lesions. In the last decade, there has been exponential growth in research into various surgical techniques and reconstructive care, enabling patients to have more surgical options. There is a wide range of surgical management procedures available, such as incision and drainage, deroofing, excisional surgery, carbon dioxide laser therapy, and skin tissue-sparing excision with electrosurgical peeling. Among these surgical procedures, wide surgical excision is the best option since it can eradicate all the affected lesions. Meanwhile, the preferred approach to reconstruction at various anatomical locations remains debatable. Here, we review a variety of surgical treatments and reconstructive techniques for HS, particularly various flap techniques for the axillary, gluteal, and inframammary regions.
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Hidradenite Supurativa , Procedimentos de Cirurgia Plástica , Humanos , Axila/cirurgia , Nádegas/cirurgia , Procedimentos Cirúrgicos Dermatológicos/métodos , Hidradenite Supurativa/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos/transplante , Resultado do TratamentoRESUMO
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.
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Inteligência Artificial , Colite Ulcerativa , Colonoscopia , Humanos , Colite Ulcerativa/diagnóstico , Estudos Retrospectivos , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Interpretação de Imagem Assistida por Computador/métodos , Curva ROC , Idoso , Reprodutibilidade dos Testes , Colo/patologia , Colo/diagnóstico por imagem , Valor Preditivo dos Testes , Diagnóstico Diferencial , Gravação em Vídeo , Aprendizado de Máquina , Estudos de Casos e ControlesRESUMO
BACKGROUND: Endoscopic therapy (ET) of gastrointestinal stromal tumors (GIST) has become a viable treatment. We intended to compare long-term outcomes of ET versus surgical resection for 2-5 cm GIST using the Surveillance, Epidemiology, and End Results (SEER) database. METHODS: A multicenter retrospective study was conducted to compare the long-term outcomes of patients treated with ET and surgical resection for GIST. The multivariate Cox proportional hazards models were used to identify predictors for patients survival. To balance the clinicopathologic characteristics, a 1:1 propensity score matching (PSM) was utilized. RESULTS: A total of 749 patients with 2-5 cm GIST were enrolled, of whom 113 accepted ET and 636 underwent surgical resection. Before PSM, there was no significant difference in long-term outcomes between ET and surgical resection (5-year overall survival (OS): 93.5% vs. 91.6%, P=0.374; 5-year cancer-specific survival (CSS): 99.1% vs. 96.5%, P=0.546; 10-year OS: 71.1% vs. 78.2%, P=0.374; 10-year CSS: 93.6% vs. 92.7%, P=0.546). After adjusting for the relevant variables using the multivariable Cox proportional hazards models, we observed that the ET and surgical resection groups were similar in OS (HR 0.726, 95%CI 0.457-1.153, P=0.175) and CSS (HR 1.286, 95%CI 0.474-3.488, P=0.621). After PSM, the long-term OS and CSS of patients with 2-5 cm GIST after ET and surgical resection were comparable. CONCLUSIONS: We found that the long-term survival of patients with 2-5 cm gastric GIST after ET and surgical resection were comparable. Further high-quality studies are needed to confirm the role of ET in 2-5 cm GIST.
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Tumores do Estroma Gastrointestinal , Pontuação de Propensão , Programa de SEER , Neoplasias Gástricas , Humanos , Tumores do Estroma Gastrointestinal/cirurgia , Tumores do Estroma Gastrointestinal/patologia , Tumores do Estroma Gastrointestinal/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/mortalidade , Taxa de Sobrevida , Gastrectomia/métodos , Resultado do Tratamento , Modelos de Riscos Proporcionais , Adulto , Carga TumoralRESUMO
AIM: To provide the direct evidence for the crucial role of trimethylamine N-oxide (TMAO) in vascular permeability and endothelial cell dysfunction under diabetic condition. METHODS: The role of TMAO on the in vitro biological effect of human retinal microvascular endothelial cells (HRMEC) under high glucose conditions was tested by a cell counting kit, wound healing, a transwell and a tube formation assay. The inflammation-related gene expression affected by TMAO was tested by real-time polymerase chain reaction (RT-PCR). The expression of the cell junction was measured by Western blotting (WB) and immunofluorescence staining. In addition, two groups of rat models, diabetic and non-diabetic, were fed with normal or 0.1% TMAO for 16wk, and their plasma levels of TMAO, vascular endothelial growth factor (VEGF), interleukin (IL)-6 and tumor necrosis factor (TNF)-α were tested. The vascular permeability of rat retinas was measured using FITC-Dextran, and the expression of zonula occludens (ZO)-1 and claudin-5 in rat retinas was detected by WB or immunofluorescence staining. RESULTS: TMAO administration significantly increased the cell proliferation, migration, and tube formation of primary HRMEC either in normal or high-glucose conditions. RT-PCR showed elevated inflammation-related gene expression of HRMEC under TMAO stimulation, while WB or immunofluorescence staining indicated decreased cell junction ZO-1 and occludin expression after high-glucose and TMAO treatment. Diabetic rats showed higher plasma levels of TMAO as well as retinal vascular leakage, which were even higher in TMAO-feeding diabetic rats. Furthermore, TMAO administration increased the rat plasma levels of VEGF, IL-6 and TNF-α while decreasing the retinal expression levels of ZO-1 and claudin-5. CONCLUSION: TMAO enhances the proliferation, migration, and tube formation of HRMEC, as well as destroys their vascular integrity and tight connection. It also regulates the expression of VEGF, IL-6, and TNF-α.
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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.
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Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Adolescente , Humanos , Prevenção do Hábito de Fumar , Controle do Tabagismo , China/epidemiologiaRESUMO
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.
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Técnicas Biossensoriais , Técnicas Biossensoriais/métodos , Hemina/química , Fibrina , Reprodutibilidade dos Testes , Limite de Detecção , Imunoensaio , DNA/química , Técnicas Eletroquímicas/métodosRESUMO
A new lignan, named pouzolignan P (1), together with 14 known ones (2 - 15) were isolated from the roots of Pouzolzia zeylanica (L.) Benn. Their structures were deduced based on the detailed spectroscopic analysis. All the isolates were evaluated for their inhibitory activities toward the ATP citrate lyase (ACLY). Among them, four lignans, isopouzolignan K (3), gnemontanins E (5), gnetuhainin I (6), and styraxlignolide D (15) showed excellent ACLY inhibitory effect with IC50 values of 9.06, 0.59, 2.63, and 7.62 µM, respectively. These compounds were further evaluated for their cholesterol-lowing effects on ox-LDL-induced high-cholesterol HepG2 cells. Compound 15 emerges as the most potent ACLY inhibitor, which significantly decreased the TC level in a dose-dependent manner. In addition, molecular docking simulations elucidated that 15 formed a strong hydrogen-bond interaction with Glu599 of ACLY, which was an important site responsible for the enzyme catalytic activity.
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ATP Citrato (pro-S)-Liase , Lignanas , ATP Citrato (pro-S)-Liase/química , Simulação de Acoplamento Molecular , Inibidores Enzimáticos/farmacologia , ColesterolRESUMO
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.
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Técnicas Biossensoriais , Neoplasias , Nitritos , Elementos de Transição , Humanos , Reprodutibilidade dos Testes , Técnicas Eletroquímicas , Eletrodos , Ácido FólicoRESUMO
INTRODUCTION: Selective intrauterine growth restriction (sIUGR), which specifically occurs in monochorionic (MC) twins, usually has a poor prognosis and the underlying mechanisms are not well understood. It is an ideal model for exploring epigenetic-modified mechanisms for fetal development in MCDA twins due to eliminating the interference of different heritable backgrounds and intrauterine environments among individuals. METHODS: The levels of ten-eleven translocation 2 (TET2) and its upstream and downstream targets miR-29b-3p and transforming growth factor beta 1 (TGFB1) were determined using RTâqPCR, western blotting, and immunohistochemistry. Using TET2 overexpression and knockdown methods, we investigated the role of TET2 in trophoblast functions. The regulatory relationships among TET2, miR-29b-3p, and TGFB1 were explored by cell migration assay, invasion assay, apoptotic ratio assays, Western blot, hMeDIP-qPCR and dual-luciferase assay. RESULTS: A consistent upregulation of TET2 and TGFB1 was observed in the smaller placental shares compared to the larger placental shares in sIUGR. Gain-of-function studies of TET2 in trophoblasts showed decreased cell invasion and increased apoptosis, whereas loss-of-function studies of TET2 rescued this effect. Mechanistic studies revealed that miR-29b-3p and TGFB1 were the upstream factor and downstream target of TET2, respectively. Furthermore, miR-29b-3p/TET2/TGFB1-smad was identified as a unique axis that regulates trophoblast invasion, migration, and apoptosis in a DNA hydroxymethylation-dependent manner. DISCUSSION: We elucidated the functional roles of TET2 and DNA hydroxymethylation in trophoblasts and identified a novel DNA regulatory mechanism, providing a basis for further exploration of DNA epigenetic regulatory patterns in sIUGR.