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1.
Nature ; 632(8024): 301-306, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39048825

RESUMEN

Molecule-based selective contacts have become a crucial component to ensure high-efficiency inverted perovskite solar cells1-5. These molecules always consist of a conjugated core with heteroatom substitution to render the desirable carrier-transport capability6-9. So far, the design of successful conjugation cores has been limited to two N-substituted π-conjugated structures, carbazole and triphenylamine, with molecular optimization evolving around their derivatives2,5,10-12. However, further improvement of the device longevity has been hampered by the concomitant limitations of the molecular stability induced by such heteroatom-substituted structures13,14. A more robust molecular contact without sacrificing the electronic properties is in urgent demand, but remains a challenge. Here we report a peri-fused polyaromatic core structure without heteroatom substitution that yields superior carrier transport and selectivity over conventional heteroatom-substituted core structures. This core structure produced a relatively chemically inert and structurally rigid molecular contact, which considerably improved the performance of perovskite solar cells in terms of both efficiency and durability. The champion device showed an efficiency up to 26.1% with greatly improved longevity under different accelerated-ageing tests.

2.
Brief Bioinform ; 25(3)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38632951

RESUMEN

In cancer genomics, variant calling has advanced, but traditional mean accuracy evaluations are inadequate for biomarkers like tumor mutation burden, which vary significantly across samples, affecting immunotherapy patient selection and threshold settings. In this study, we introduce TMBstable, an innovative method that dynamically selects optimal variant calling strategies for specific genomic regions using a meta-learning framework, distinguishing it from traditional callers with uniform sample-wide strategies. The process begins with segmenting the sample into windows and extracting meta-features for clustering, followed by using a pre-trained meta-model to select suitable algorithms for each cluster, thereby addressing strategy-sample mismatches, reducing performance fluctuations and ensuring consistent performance across various samples. We evaluated TMBstable using both simulated and real non-small cell lung cancer and nasopharyngeal carcinoma samples, comparing it with advanced callers. The assessment, focusing on stability measures, such as the variance and coefficient of variation in false positive rate, false negative rate, precision and recall, involved 300 simulated and 106 real tumor samples. Benchmark results showed TMBstable's superior stability with the lowest variance and coefficient of variation across performance metrics, highlighting its effectiveness in analyzing the counting-based biomarker. The TMBstable algorithm can be accessed at https://github.com/hello-json/TMBstable for academic usage only.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Genómica/métodos , Genoma , Algoritmos
3.
Blood ; 144(7): 729-741, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38805639

RESUMEN

ABSTRACT: Loss of long-term hematopoietic stem cell (LT-HSC) function ex vivo hampers the success of clinical protocols that rely on culture. However, the kinetics and mechanisms through which this occurs remain incompletely characterized. In this study, through time-resolved single-cell RNA sequencing, matched in vivo functional analysis, and the use of a reversible in vitro system of early G1 arrest, we defined the sequence of transcriptional and functional events that occur during the first ex vivo division of human LT-HSCs. We demonstrated that the sharpest loss in LT-HSC repopulation capacity happens early on, between 6 and 24 hours of culture, before LT-HSCs commit to cell cycle progression. During this time window, LT-HSCs adapt to the culture environment, limit the global variability in gene expression, and transiently upregulate gene networks involved in signaling and stress responses. From 24 hours, LT-HSC progression past early G1 contributes to the establishment of differentiation programs in culture. However, contrary to the current assumptions, we demonstrated that the loss of HSC function ex vivo is independent of cell cycle progression. Finally, we showed that targeting LT-HSC adaptation to culture by inhibiting the early activation of JAK/STAT signaling improves HSC long-term repopulating function ex vivo. Collectively, our study demonstrated that controlling early LT-HSC adaptation to ex vivo culture, for example, via JAK inhibition, is critically important to improve HSC gene therapy and expansion protocols.


Asunto(s)
Ciclo Celular , Células Madre Hematopoyéticas , Humanos , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/metabolismo , Células Cultivadas , Transducción de Señal , Diferenciación Celular , Técnicas de Cultivo de Célula/métodos , Adaptación Fisiológica
4.
J Cell Mol Med ; 28(9): e18354, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38686557

RESUMEN

Infections caused by Candida species, especially Candida albicans, threaten the public health and create economic burden. Shortage of antifungals and emergence of drug resistance call for new antifungal therapies while natural products were attractive sources for developing new drugs. In our study, fangchinoline, a bis-benzylisoquinoline alkaloid from Chinese herb Stephania tetrandra S. Moore, exerted antifungal effects on planktonic growth of several Candida species including C. albicans, with MIC no more than 50 µg/mL. In addition, results from microscopic, MTT and XTT reduction assays showed that fangchinoline had inhibitory activities against the multiple virulence factors of C. albicans, such as adhesion, hyphal growth and biofilm formation. Furthermore, this compound could also suppress the metabolic activity of preformed C. albicans biofilms. PI staining, followed by confocal laser scanning microscope (CLSM) analysis showed that fangchinoline can elevate permeability of cell membrane. DCFH-DA staining suggested its anti-Candida mechanism also involved overproduction of intracellular ROS, which was further confirmed by N-acetyl-cysteine rescue tests. Moreover, fangchinoline showed synergy with three antifungal drugs (amphotericin B, fluconazole and caspofungin), further indicating its potential use in treating C. albicans infections. Therefore, these results indicated that fangchinoline could be a potential candidate for developing anti-Candida therapies.


Asunto(s)
Antifúngicos , Bencilisoquinolinas , Biopelículas , Candida albicans , Pruebas de Sensibilidad Microbiana , Especies Reactivas de Oxígeno , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Candida albicans/efectos de los fármacos , Candida albicans/crecimiento & desarrollo , Antifúngicos/farmacología , Especies Reactivas de Oxígeno/metabolismo , Bencilisoquinolinas/farmacología , Hifa/efectos de los fármacos , Hifa/crecimiento & desarrollo
5.
J Am Chem Soc ; 146(7): 4993-5004, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38333965

RESUMEN

Alkyne hydrogenation on palladium-based catalysts modified with silver is currently used in industry to eliminate trace amounts of alkynes in alkenes produced from steam cracking and alkane dehydrogenation processes. Intensive efforts have been devoted to designing an alternative catalyst for improvement, especially in terms of selectivity and catalyst cost, which is still far away from that as expected. Here, we describe an atomic design of a high-performance Ni-based intermetallic catalyst aided by active machine learning combined with density functional theory calculations. The engineered NiIn catalyst exhibits >97% selectivity to ethylene and propylene at the full conversion of acetylene and propyne at mild temperature, outperforming the reported Ni-based catalysts and even noble Pd-based ones. Detailed mechanistic studies using theoretical calculations and advanced characterizations elucidate that the atomic-level defined coordination environment of Ni sites and well-designed hybridization of Ni 3d with In 5p orbital determine the semihydrogenation pathway.

6.
J Clin Microbiol ; 62(2): e0012023, 2024 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-38284761

RESUMEN

Rapid phenotypic detection assays, including Carba NP and its variants, are widely applied for clinical diagnosis of carbapenemase-producing Enterobacterales (CPE). However, these tests are based on the acidification of the pH indicator during carbapenem hydrolysis, which limits test sensitivity and speed, especially for the detection of CPE producing low-activity carbapenem (e.g., OXA-48 variants). Herein, we developed a novel rapid and sensitive CPE detection method (Carba PBP) that could measure substrate (meropenem) consumption based on penicillin-binding protein (PBP). Meropenem-specific PBP was used to develop a competitive lateral flow assay (LFA) for meropenem identification. For the detection of carbapenemase activity, meropenem concentration was optimized using a checkerboard assay. The performance of Carba PBP was evaluated and compared with that of Carba NP using a panel of 94 clinical strains characterized by whole-genome sequencing and carbapenem susceptibility test. The limit of detection of PBP-based LFA for meropenem identification was 7 ng mL-1. Using 10 ng mL-1 meropenem as the substrate, Carba PBP and Carba NP could detect 10 ng mL-1 carbapenemase within 25 min and 1,280 ng mL-1 CPE in 2 h, respectively. The sensitivity and specificity were 100% (75/75) and 100% (19/19) for Carba PBP and 85.3% (64/75) and 100% (19/19) for Carba NP, respectively. When compared with Carba NP, Carba PBP showed superior performance in detecting all the tested CPE strains (including OXA-48-like variants) within 25 min and presented two orders of magnitude higher analytical sensitivity, demonstrating potential for clinical diagnosis of CPE. IMPORTANCE This study successfully achieved the goal of carbapenemase activity detection with both high sensitivity and convenience, offering a convenient lateral flow assay for clinical diagnosis of carbapenemase-producing Enterobacterales.


Asunto(s)
Proteínas Bacterianas , beta-Lactamasas , Humanos , Proteínas de Unión a las Penicilinas/genética , Meropenem/farmacología , Pruebas de Sensibilidad Microbiana , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , beta-Lactamasas/metabolismo , Carbapenémicos/farmacología , Sensibilidad y Especificidad
7.
Biomacromolecules ; 25(3): 1602-1611, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38323536

RESUMEN

Helicobacter pylori can cause various gastric conditions including stomach cancer in an acidic environment. Although early H. pylori infections can be treated by antibiotics, prolonged antibiotic administrations may lead to the development of antimicrobial resistance, compromising the effectiveness of the treatments. Antimicrobial peptides (AMPs) have been reported to possess unique advantages against antimicrobial-resistant bacteria due to their rapid physical membrane disruptions and anti-inflammation/immunoregulation properties. Herein, we have developed an AMP hydrogel, which can be orally administered for the treatment of H. pylori infection. The hydrogel has potent antimicrobial activity against H. pylori, achieving bacterial eradication within minutes of action. Compared with the AMP solution, the hydrogel formulation significantly reduced the cytotoxicity and enhanced proteolytic stability. In vivo experiments suggested that the hydrogel formed at pH 4 had superior therapeutic effects to those at pH 7 and 10 hydrogels, attributed to its rapid release and bactericidal action within the acidic stomach environment. Compared to conventional antibiotic treatments, the AMP hydrogel had the advantages of fast bacterial killing in the gastric juice and obviated proton pump inhibitors during the treatment. Although both the AMP hydrogel and antibiotics suppressed the expression of pro-inflammatory cytokines, the former uniquely promoted inflammation resolution. These results indicate that the AMP hydrogels with effectiveness and biosafety may be potential candidates for the clinical treatment of H. pylori infections.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Humanos , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/metabolismo , Infecciones por Helicobacter/microbiología , Péptidos Antimicrobianos , Hidrogeles/farmacología , Hidrogeles/uso terapéutico , Antibacterianos
8.
Environ Sci Technol ; 58(15): 6628-6636, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38497595

RESUMEN

Biomass waste-derived engineered biochar for CO2 capture presents a viable route for climate change mitigation and sustainable waste management. However, optimally synthesizing them for enhanced performance is time- and labor-intensive. To address these issues, we devise an active learning strategy to guide and expedite their synthesis with improved CO2 adsorption capacities. Our framework learns from experimental data and recommends optimal synthesis parameters, aiming to maximize the narrow micropore volume of engineered biochar, which exhibits a linear correlation with its CO2 adsorption capacity. We experimentally validate the active learning predictions, and these data are iteratively leveraged for subsequent model training and revalidation, thereby establishing a closed loop. Over three active learning cycles, we synthesized 16 property-specific engineered biochar samples such that the CO2 uptake nearly doubled by the final round. We demonstrate a data-driven workflow to accelerate the development of high-performance engineered biochar with enhanced CO2 uptake and broader applications as a functional material.


Asunto(s)
Dióxido de Carbono , Aprendizaje Basado en Problemas , Carbón Orgánico , Adsorción
9.
BMC Psychiatry ; 24(1): 414, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38834981

RESUMEN

BACKGROUND: Fostering empathy has been continuously emphasized in the global medical education. Empathy is crucial to enhance patient-physician relationships, and is associated with medical students' academic and clinical performance. However, empathy level of medical students in China and related influencing factors are not clear. METHODS: This was a cross-sectional study among medical students in 11 universities. We used the Jefferson Scale of Empathy Student-version of Chinese version to measure empathy level of medical students. Factors associated with empathy were identified by the univariate and multivariate logistic regression analyses. Based on the variables identified above, the nomogram was established to predict high empathy probability of medical students. Receiver operating characteristic curve, calibration plot and decision curve analysis were used to evaluate the discrimination, calibration and educational utility of the model. RESULTS: We received 10,901 samples, but a total of 10,576 samples could be used for further analysis (effective response rate of 97.02%). The mean empathy score of undergraduate medical students was 67.38 (standard deviation = 9.39). Six variables including gender, university category, only child or not, self-perception doctor-patient relationship in hospitals, interest of medicine, Kolb learning style showed statistical significance with empathy of medical students (P < 0.05). Then, the nomogram was established based on six variables. The validation suggested the nomogram model was well calibrated and had good utility in education, as well as area under the curve of model prediction was 0.65. CONCLUSIONS: We identify factors influencing empathy of undergraduate medical students. Moreover, increasing manifest and hidden curriculums on cultivating empathy of medical students may be needed among medical universities or schools in China.


Asunto(s)
Educación de Pregrado en Medicina , Empatía , Relaciones Médico-Paciente , Estudiantes de Medicina , Humanos , Estudiantes de Medicina/psicología , Estudiantes de Medicina/estadística & datos numéricos , Estudios Transversales , Masculino , Femenino , China , Adulto Joven , Adulto , Nomogramas
10.
Inj Prev ; 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38768979

RESUMEN

BACKGROUND: Practical interventions of fall prevention are challenging for infants and toddlers. This study aimed to explore specific details of falls that occurred at home for kids 0-3 years old using key information from social media platforms, which provided abundant data sources for fall events. METHODS: We used internet-based search techniques to collect fall events information from 2013 to 2023. The search was restricted and implemented between 1 and 12 April 2023. Online platforms included Baidu, Weibo, WeChat, TikTok, Toutiao and Little Red Book. A qualitative descriptive approach was used to analyse the fall events and major factors, including the fall event time, child age, environmental factors and behavioural characteristics of children and caregivers. RESULTS: We identified 1005 fall injury cases among infants and toddlers. Fall mechanisms included falls from household furniture (71.2%), falls from height (21.4%) and falls on the same level (7.4%). Environmental risk factors mainly consisted of not using or installing bed rails incorrectly, a gap between beds, unstable furniture, slippery ground and windows without guardrails. Behavioural factors included caregivers leaving a child alone, lapsed attention, turning around to retrieve something, misusing baby products, inadequately holding the child and falling asleep with children. Child behavioural factors included walking or running while holding an object in hand or mouth and underdeveloped walking skills. CONCLUSION: Interventions for preventing falls should be designed specifically for Chinese families, especially considering family function in the context of Chinese culture. Social media reports could provide rich information for researchers.

11.
BMC Public Health ; 24(1): 1035, 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38614987

RESUMEN

INTRODUCTION: Widespread concern exists in today's world regarding self-harm and interpersonal violence. This study to analyze the changes in temporal trends and spatial patterns of risk factors and burdens of self-harm and interpersonal violence using the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019. METHODS: Temporal trends in self-harm and interpersonal violence were initially summarized using the estimated annual percentage change (EAPC). Data were compiled and visualized to delineate changes in disease burden and factors influencing self-harm and interpersonal violence from 1990 to 2019, stratified by gender, age and GBD region. RESULTS: In 2019, the DALY rates of self-harm were 424.7(95% UI 383.25, 466.93). Over the period from 1999 to 2019, self-harm exhibited an overall decreasing trend, with the EAPC of -1.5351 (95% CI -1.6194, -1.4507), -2.0205 (95% CI -2.166, -1.8740) and -2.0605 (95% CI -2.2089, -1.9119), respectively. In contrast, the incidence rate of interpersonal violence was significantly higher than self-harm, with a rate of 413.44 (95% UI 329.88, 502.37) per 100,000 population. Mortality and DALYs of interpersonal violence were lower than those of self-harm, at 5.22 (95% UI 4.87, 5.63) and 342.43 (95% UI 316.61, 371.55). Disease burden of self-harm and interpersonal violence varied by gender, age groups and region. Specific risk factors showed that alcohol use, high temperature and drug use were the main risk factors for self-harm, while alcohol use, intimate partner violence and high temperature were associated with interpersonal violence. Low temperature was a common protective factor for both self-harm and interpersonal violence. The burden of self-harm and interpersonal violence was attributed to different factors influences in different SDI regions. CONCLUSIONS: The study explored temporal trends and spatial distribution of the global disease burden of self-harm and interpersonal violence, emphasizing the significant impact of factors such as alcohol use, temperature, and drug use on disease burden. Further research and policy actions are needed to interpret recent changes of disease burden of self-harm and interpersonal violence, and dedicated efforts should be implemented to devise evidence-based interventions and policies to curtail risk factors and protect high-risk groups.


Asunto(s)
Violencia de Pareja , Conducta Autodestructiva , Humanos , Carga Global de Enfermedades , Conducta Autodestructiva/epidemiología , Consumo de Bebidas Alcohólicas , Factores de Riesgo
12.
Ecotoxicol Environ Saf ; 282: 116682, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39002380

RESUMEN

The effectiveness, tolerance, and safety of pesticides must be established before their scientific or rational. This study evaluates the field control efficacy of broflanilide, tetraniliprole, and chlorantraniliprole in combating Spodoptera frugiperda in maize crops, as well as the resistance of S. frugiperda to these three diamide pesticides after exposure. By assessing field control efficiency, toxicity, effects on development and reproduction, and detoxification enzyme activity of these diamide pesticides on S. frugiperda, highlights broflanilide's significant insecticidal potential. A highly sensitive and efficient method using QuEChERS/HPLCMS/MS was developed to simultaneously detect residues of these three pesticides on maize. Initial concentrations of broflanilide, tetraniliprole, and chlorantraniliprole ranged from 2.13 to 4.02 mg/kg, with their respective half-lives varying between 1.23 and 1.51 days. Following foliar application, by the time of harvest, the terminal residue concentrations of these pesticides were all under 0.01 mg/kg. Chronic dietary intake risk assessments and cumulative chronic dietary exposure for three pesticides indicated that the general population's terminal residue concentration was within acceptable limits. Not only does this research provide valuable insights into field control efficiency, insecticidal effects, resistance, residues, and risk assessment results of broflanilide, tetraniliprole, and chlorantraniliprole on maize, but additionally, it also paves the way for setting suitable Maximum Residue Limits (MRLs) values based on pre-harvest interval values, rational dosage, and application frequency.


Asunto(s)
Insecticidas , Spodoptera , Zea mays , ortoaminobenzoatos , Spodoptera/efectos de los fármacos , Animales , Insecticidas/toxicidad , Medición de Riesgo , ortoaminobenzoatos/toxicidad , Productos Agrícolas , Residuos de Plaguicidas/toxicidad , Residuos de Plaguicidas/análisis , Diamida/toxicidad , Larva/efectos de los fármacos , Resistencia a los Insecticidas
13.
Ann Gen Psychiatry ; 23(1): 15, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664741

RESUMEN

BACKGROUND: Patients with mood disorders usually require repeated and prolonged hospitalization, resulting in a heavy burden on healthcare resources. This study aims to identify variables associated with length of stay(LOS) of repeatedly hospitalized patients with mood disorders and to provide information for optimizing psychiatry management and healthcare resource allocation. METHODS: Electronic medical records (EMRs) of repeatedly hospitalized patients with mood disorders from January 2010 to December 2018 were collected and retrospectively analyzed. Chi-square and t-test were adopted to investigate the differences in characteristics between the two groups of short LOS and long LOS. Generalized estimating equation (GEE) was conducted to investigate potential factors influencing LOS. RESULTS: A total of 2,009 repeatedly hospitalized patients with mood disorders were enrolled, of which 797 (39.7%) had a long LOS and 1,212 (60.3%) had a short LOS. Adverse effects of treatment, continuous clinical manifestation, chronic onset type, suicide attempt, comorbidity and use of antidepressants were positively associated with long LOS among all repeatedly hospitalized patients with mood disorders (P < 0.050). For patients with depression, factors associated with long LOS consisted of age, monthly income, adverse effects of treatment, continuous clinical manifestation, suicide attempt and comorbidity (P < 0.050). Whereas, for patients with bipolar disorder (BD), adverse effects of treatment, four or more hospitalizations and use of antidepressants contributed to the long LOS (P < 0.050). Influencing factors of LOS also vary among patients with different effectiveness of treatment. CONCLUSION: The LOS in repeatedly hospitalized patients with mood disorders was influenced by multiple factors. There were discrepancies in the factors affecting LOS in patients with different diagnoses and effectiveness of treatment, and specific factors should be addressed when evaluating the LOS.

14.
Int J Neurosci ; : 1-15, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38738478

RESUMEN

BACKGROUND: Sciatica is a phrase used to describe radiating leg discomfort. The most common cause is lumbar disc herniation (LDH), which is considered to start in the nucleus pulposus. Advancements in lipidomics and metabolomics have unveiled the complex role of fatty acid metabolism (FAM) in both healthy and pathological states. However, the specific roles of fatty acid metabolism-related genes (FAMGs) in shaping therapeutic approaches, especially in LDH, remain largely unexplored and are a subject of ongoing research. METHODS: The junction of the weighted correlation network analysis (WGCNA) test with 6 FAMGs enabled the finding of FAMGs. Gene set variation analysis (GSVA) was used to identify the possible biological activities and pathways of FAMGs. LASSO was used to determine diagnostic effectiveness of the four FAMGs in diagnosing LDH. GSE124272, GSE147383, GSE150408, and GSE153761 were utilized to confirm the levels of expression of four FAMGs. RESULTS: Four FAMGs were discovered [Acyl-CoA Thioesterase 4 (ACOT4), Cytochrome P450 Family 4 Subfamily A Member 11 (CYP4A11), Acyl-CoA Dehydrogenase Long Chain (ACADL), Enoyl-CoA Hydratase and 3-Hydroxyacyl CoA Dehydrogenase (EHHADH)] For biological function analysis, mhc class ib receptor activity, response to thyroxine, response to l phenylalanine derivative were emphasized. CONCLUSIONS: FAMGs can help with prognosis and immunology, and provide evidence for fatty acid metabolism-related targeted therapeutics. In LDH, FAMGs and their interactions with immune cells might be therapeutic targets.

15.
BMC Med Educ ; 24(1): 832, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090597

RESUMEN

BACKGROUND: Medical school learning environment (MSLE) has a holistic impact on students' psychosomatic health, academic achievements, and personal development. Students in different grades perceive MSLE in different ways. Thus, it is essential to investigate the specific role of student's grade in the perception of MSLE. METHODS: Using the Johns Hopkins Learning Environment Scale (JHLES) as a quantification instrument for the perception level of MSLE, 10,901 medical students in 12 universities in China were categorized into low or high JHLES group according to their questionnaires. We investigated the relationship between student's grade and JHLES category by univariate analysis employing Pearson Chi-square test and Welch's ANOVA. Then multivariable logistic regression analysis confirmed the predictive efficacy of student's grade. A nomogram concerning the prediction of low JHLES score probability in medical students was also constructed. RESULTS: A significant difference between two JHLES categories among students in different grades was observed (p < 0.001), with the proportion of the high JHLES group dominating in grade 1, 5, and the graduate subgroups (p < 0.001). The mean JHLES score declined especially in the third and fourth graders compared to freshmen (p < 0.001), while the mean score among the fifth graders had a remarkable rebound from the third graders (p < 0.001). Most imperatively, identified by multivariable logistic regression analysis, students in grade 3 (OR = 1.470, 95% CI = 1.265-1.709, p < 0.001) and 4 (OR = 1.578, 95% CI = 1.326-1.878, p < 0.001) perceived more negatively than freshmen. The constructed nomogram provided a promising prediction model for student's low JHLES score probability, with accuracy, accordance, and discrimination (area under the curve (AUC) = 0.627). CONCLUSION: The student's grade was a significant influencing factor in medical students' perception of MSLE. The perceptions among the third and fourth graders got worse, probably due to the worrying changes in various aspects of MSLE during that period. The relevant and appropriate interventions to improve medical students' perceptions are urgently needed.


Asunto(s)
Estudiantes de Medicina , Humanos , Estudiantes de Medicina/psicología , Estudios Transversales , China , Femenino , Masculino , Aprendizaje , Encuestas y Cuestionarios , Facultades de Medicina , Adulto Joven , Percepción , Educación de Pregrado en Medicina , Adulto
16.
Molecules ; 29(8)2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38675680

RESUMEN

This study presents a method for analyzing dimethomorph residues in lychee using QuEChERS extraction and HPLC-MS/MS. The validation parameters for this method, which include accuracy, precision, linearity, and recovery, indicate that it meets standard validation requirements. Following first-order kinetics, the dissipation dynamic of dimethomorph in lychee was determined to range from 6.4 to 9.2 days. Analysis of terminal residues revealed that residues in whole lychee were substantially greater than those in the pulp, indicating that dimethomorph residues are predominantly concentrated in the peel. When applied twice and thrice at two dosage levels with pre-harvest intervals (PHIs) of 5, 7, and 10 days, the terminal residues in whole lychee ranged from 0.092 to 1.99 mg/kg. The terminal residues of the pulp ranged from 0.01 to 0.18 mg/kg, with the residue ratio of whole lychee to pulp consistently exceeding one. The risk quotient (RQ) for dimethomorph, even at the recommended dosage, was less than one, indicating that the potential for damage was negligible. This study contributes to the establishment of maximum residue limits (MRLs) in China by providing essential information on the safe application of dimethomorph in lychee orchards.


Asunto(s)
Litchi , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Litchi/química , Morfolinas/análisis , Residuos de Plaguicidas/análisis , Contaminación de Alimentos/análisis
17.
Molecules ; 29(11)2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38893566

RESUMEN

DFT and TD-DFT were used in this article to investigate the effects of different substitutions at multiple sites on the photophysical mechanism of bis-HBX in the gas phase. Four different substitution modes were selected, denoted as A1 (X=Me, Y=S), A2 (X=OMe, Y=S), B1 (X=Me, Y=NH), and C1 (X=Me, Y=O). The geometric parameters proved that the IHBs enhanced after photoexcitation, which was conducive to promote the ESIPT process. Combining the analysis of the PECs, it was revealed that the bis-HBX molecule underwent the ESIPT process, and the ease of the ESIPT process was in the order of A1 > A2> B1 > C1. In particular, the TICT process in A1 and B1 promoted the occurrence of the ESIPT process. In addition, the IC process was identified, particularly in C1. Meanwhile, the calculation of fluorescence lifetime and fluorescence rate further confirmed that A1 was the most effective fluorescent probe molecule. This theoretical research provides an innovative theoretical reference for regulating ESIPT reactions and optimizing fluorescent probe molecules.

18.
Wei Sheng Yan Jiu ; 53(3): 427-434, 2024 May.
Artículo en Zh | MEDLINE | ID: mdl-38839584

RESUMEN

OBJECTIVE: To investigate the association between long-term fine particulate matter(PM_(2.5)) exposure and the risk of chronic kidney disease(CKD) in people with abnormal metabolism syndrome(MS) components. METHODS: Based on health checkup data from a hospital in Beijing, a retrospective cohort study was used to collect annual checkup data from 2013-2019. A questionnaire was used to obtain information on demographic characteristics and lifestyle habits. We measured blood pressure, height, weight, waist circumference, concentrations of triglycerides(TG), fasting glucose, and high-density lipoprotein cholesterol(HDL-C). Longitude and latitude were also extracted from the addresses of the study subjects for pollutant exposure data estimation. Logistic regression models were used to explore the estimated effect of long-term PM_(2.5) exposure on the risk of CKD prevalence in people with abnormal MS components. Two-pollutant and multi-pollutant models were developed to test the stability of these result. Subgroup analysis was conducted based on age, the presence of MS, individual MS component abnormalities, and dual-component MS abnormalities. RESULTS: The study included 1540 study subjects with abnormal MS components at baseline, 206 with CKD during the study period. The association between long-term PM_(2.5) exposure and increased risk of CKD in people with abnormal MS fractions was statistically significant, with a 2.26-fold increase in risk of CKD for every 10 µg/m~3 increase in PM_(2.5) exposure(OR=3.26, 95% CI 2.72-3.90). The result in the dual-pollutant models and multi-pollutant models suggested that the association between long-term PM_(2.5) exposure and increased risk of CKD in people with abnormal MS fractions remained stable after controlling for contemporaneous confounding by other air pollutants. The result of subgroup analysis revealed that individuals aged 45 or older, without MS, with TG<1.7 mmol/L, HDL-C≥1.04 mmol/L, without hypertension, and with central obesity and high blood sugar had a stronger association between PM_(2.5) exposure and CKD-related health effects. CONCLUSION: Long-term exposure to PM_(2.5) may increase the risk of CKD in people with abnormal MS components. More attention should be paid to middle-aged and elderly people aged ≥45 years, people with central obesity and hyperglycemia.


Asunto(s)
Exposición a Riesgos Ambientales , Síndrome Metabólico , Material Particulado , Insuficiencia Renal Crónica , Humanos , Insuficiencia Renal Crónica/etiología , Insuficiencia Renal Crónica/epidemiología , Síndrome Metabólico/etiología , Síndrome Metabólico/epidemiología , Femenino , Masculino , Material Particulado/efectos adversos , Material Particulado/análisis , Persona de Mediana Edad , Estudios Retrospectivos , Exposición a Riesgos Ambientales/efectos adversos , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Adulto , Estudios de Cohortes , Factores de Riesgo , Beijing/epidemiología , Anciano , Encuestas y Cuestionarios , Modelos Logísticos
19.
Environ Sci Pollut Res Int ; 31(25): 37316-37325, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38769265

RESUMEN

Litchi and longan pests significantly affect crop yield and quality. Chemical prevention and control are very effective for production; therefore, it is crucial to study fate assessment and appropriate field efficacy before pesticide application on crops to appropriately assess the health and ecological risks linked with these agents. This study conducted Good Agricultural Practice (GAP) field trials and laboratory experiments to elucidate the dissipation, terminal residues, and efficacy of methoxyfenozide on litchi and longan in six locations throughout China. To detect methoxyfenozide residues on litchi and longan, a QuEChERS/UPLC-MS/MS-based method was designed. The initial methoxyfenozide levels in litchi and longan ranged from 2.21-2.86 to 0.83-0.95 mg kg-1 and indicated half-lives of 5.1-5.3 and 5.3-5.7 days, respectively. After 7 days of foliage treatment, the concentrations of terminal methoxyfenozide residue were 0.78-2.61 and 0.02-1.01 mg kg-1, which were less than the established maximum residue limit for methoxyfenozide in litchi and longan. The chronic (acceptable daily intake = 0.0055-0.0331%) dietary intake risk analysis for methoxyfenozide in longan and litchi indicated acceptable concentrations of terminal residue for the general population. Methoxyfenozide in litchi and longan was readily degraded in first-order kinetics models, the degradation rate on longan was higher than that on litchi, and their dietary risks were negligible to consumers. Two hundred forty grams per liter of methoxyfenozide suspension concentrate (SC) represents a highly efficacious insecticidal dose to control litchi and longan pests and indicates a significant application potential as it is rapidly degraded and linked with reduced post-treatment residue levels.


Asunto(s)
Hidrazinas , Litchi , Litchi/química , Animales , Insecticidas , China , Residuos de Plaguicidas , Hormonas Juveniles
20.
Sci Total Environ ; 944: 173881, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-38871331

RESUMEN

Plastic debris such as microplastics (MPs) and nanoplastics (NPTs), along with antibiotic resistance genes (ARGs), are pervasive in the environment and are recognized as significant global health and ecological concerns. Micro-/nano-plastics (MNPs) have been demonstrated to favor the spread of ARGs by enhancing the frequency of horizontal gene transfer (HGT) through various pathways. This paper comprehensively and systematically reviews the current study with focus on the influence of plastics on the HGT of ARGs. The critical role of MNPs in the HGT of ARGs has been well illustrated in sewage sludge, livestock farms, constructed wetlands and landfill leachate. A summary of the performed HGT assay and the underlying mechanism of plastic-mediated transfer of ARGs is presented in the paper. MNPs could facilitate or inhibit HGT of ARGs, and their effects depend on the type, size, and concentration. This review provides a comprehensive insight into the effects of MNPs on the HGT of ARGs, and offers suggestions for further study. Further research should attempt to develop a standard HGT assay and focus on investigating the impact of different plastics, including the oligomers they released, under real environmental conditions on the HGT of ARGs.


Asunto(s)
Farmacorresistencia Microbiana , Transferencia de Gen Horizontal , Microplásticos , Plásticos , Farmacorresistencia Microbiana/genética
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