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1.
Bioelectrochemistry ; 160: 108777, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38991474

RESUMEN

To take advantage of the high specificity of enzymatic catalysis along with the high efficiency of electrochemical cofactor regeneration, a bacterial surface displayed enzyme-nanomaterial hybrid bioelectrocatalytic system is herein developed. A cofactor-dependent xylose reductase, capable of reducing xylose to xylitol, is displayed on the surface of Bacillus subtilis, followed by the attachment of copper nanomaterials via the binding of His-tagged enzyme with the nickel ion. This hybrid system can regenerate NADPH with a highest efficiency of 71.6% in 4 h without the usage of extra electron mediators, and 2.35 mM of xylitol can be synthesized after a series of optimization processes. This work opens up new possibilities for the construction and application of bioelectrocatalytic systems with enzyme-nanomaterial hybrids.

2.
Biodes Res ; 6: 0039, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39081856

RESUMEN

Terpenoids of substantial industrial interest are mainly obtained through direct extraction from plant sources. Recently, microbial cell factories or in vitro enzymatic biosystems have emerged as promising alternatives for terpenoid production. Here, we report a route for the synthesis of α-farnesene based on an in vitro enzyme cascade reaction using methanol as an inexpensive and renewable C1 substrate. Thirteen biocatalytic reactions divided into 2 modules were optimized and coupled to achieve methanol-to-α-farnesene conversion via integration with natural thylakoid membranes as a green energy engine. This in vitro enzymatic biosystem driven by light enabled the production of 1.43 and 2.40 mg liter-1 α-farnesene using methanol and the intermediate glycolaldehyde as substrates, respectively. This work could provide a promising strategy for developing light-powered in vitro biosynthetic platforms to produce more natural compounds synthesized from C1 substrates.

3.
Chem Asian J ; : e202400366, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39058230

RESUMEN

The rational design of efficient, stable, low-cost non-precious metal-based electrocatalysts with enhanced oxygen reduction reaction (ORR) activity has attracted widespread attention. In this study, a novel electrocatalyst, Fe/Co-N-MWCNT, was prepared by in-situ growth of ZIF-8 and Fe/Co-Phen on multi-walled carbon nanotubes (MWCNTs), then pyrolysis under different temperature to obtain optimal one. During the pyrolysis process, the incorporation of Fe and Co facilitated the formation of metal active sites and Fe-Co alloy, thereby promoting electron transfer and enhancing the ORR activity. Compared to Pt/C (E1/2 = 0.854V, JL = 4.90 mA cm-2), Fe/Co-N-MWCNT demonstrated a comparable half-wave potential (E1/2 = 0.812V) and an enhanced limiting current density (JL = 5.37 mA cm-2). Furthermore, Fe/Co-N-MWCNT was stable and showed no significant change after 2000 cycles, with only a negative shift of 7 mV in E1/2. Ampere response testing revealed that the current decay of Fe/Co-N-MWCNT after 10000 s was only about 7.8%, while that of Pt/C was about 18.4%. Due to its excellent catalytic stability, Fe/Co-N-MWCNT was demonstrated to be an excellent candidate for rechargeable zinc-air batteries. The outstanding electrocatalytic performance of Fe/Co-N-MWCNT can be attributed to its high pyridinic nitrogen content, the unique structure and abundant metal active sites.

4.
Biomed Pharmacother ; 176: 116832, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38850659

RESUMEN

Berberine (BBR) is a compound derived from Chinese herbal medicine, known for its anticancer properties through multiple signaling pathways. However, whether BBR can inhibit tumor growth by participating in ferroptosis remains unconfirmed. In this study, we demonstrated that berberine synergistically inhibited NSCLC in combination with multiple ferroptosis inducers, and this combination synergistically down-regulated the mRNA and protein expression of SLC7A11, GPX4, and NRF2, resulting in ferroptosis accompanied by significant depletion of GSH, and aberrant accumulation of reactive oxygen species and malondialdehyde. In a lung cancer allograft model, the combination treatment exhibited enhanced anticancer effects compared to using either drug alone. Notably, p53 is critical in determining the ferroptosis sensitivity. We found that the combination treatment did not elicit a synergistic anticancer effect in cells with a p53 mutation or with exogenous expression of mutant p53. These findings provide insight into the mechanism by which combination induces ferroptosis and the regulatory role of p53 in this process. It may guide the development of new strategies for treating NSCLC, offering great medical potential for personal diagnosis and treatment.


Asunto(s)
Sistema de Transporte de Aminoácidos y+ , Berberina , Carcinoma de Pulmón de Células no Pequeñas , Sinergismo Farmacológico , Ferroptosis , Neoplasias Pulmonares , Fosfolípido Hidroperóxido Glutatión Peroxidasa , Transducción de Señal , Proteína p53 Supresora de Tumor , Ferroptosis/efectos de los fármacos , Berberina/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Humanos , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Fosfolípido Hidroperóxido Glutatión Peroxidasa/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Sistema de Transporte de Aminoácidos y+/metabolismo , Sistema de Transporte de Aminoácidos y+/genética , Animales , Transducción de Señal/efectos de los fármacos , Línea Celular Tumoral , Especies Reactivas de Oxígeno/metabolismo , Ratones , Ratones Desnudos , Ratones Endogámicos BALB C , Factor 2 Relacionado con NF-E2/metabolismo , Células A549
5.
Plants (Basel) ; 13(11)2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38891336

RESUMEN

Natural plants contain numerous chemical compounds that are beneficial to human health. The berries from the Lycium genus are widely consumed and are highly nutritious. Moreover, their chemical constituents have attracted attention for their health-promoting properties. In East Asia, there are three varieties of the Lycium genus (Lycium barbarum L., Lycium chinense Miller, and L. ruthenicum Murray) that possess medicinal value and are commonly used for treating chronic diseases and improving metabolic disorders. These varieties are locally referred to as "red Goji berries" or "black Goji berries" due to their distinct colors, and they differ in their chemical compositions, primarily in terms of carotenoid and anthocyanin content. The pharmacological functions of these berries include anti-aging, antioxidant, anti-inflammatory, and anti-exercise fatigue effects. This review aims to analyze previous and recent studies on the active ingredients and pharmacological activities of these Lycium varieties, elucidating their signaling pathways and assessing their impact on the gut microbiota. Furthermore, the potential prospects for using these active ingredients in the treatment of COVID-19 are evaluated. This review explores the potential targets of these Lycium varieties in the treatment of relevant diseases, highlighting their potential value in drug development.

6.
Front Pediatr ; 12: 1332020, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38813546

RESUMEN

Objective: The study aims to analyze the clinical characteristics of acute phase of SARS-CoV-2 infection in children aged 0-17 years with the Omicron variant, and summarize the persistent symptoms or new-onset clinical manifestations from 4 to 12 weeks after acute COVID. Explore the association between the vaccination status and SARS-CoV-2 neutralizing antibody levels post infection among preschool-aged children. The comprehensive study systematically describes the clinical characteristics of children infected with SARS-CoV-2, providing a foundation for diagnosis and evaluating long-term COVID in pediatric populations. Methods: The study enrolled children who were referred to the Children's Hospital, Capital Institute of Pediatrics, (Beijing, China) from January 10, 2023 to March 31, 2023. Participants were classified as infant and toddlers, preschool, school-age, and adolescent groups. Children or their legal guardians completed survey questionnaires to provide information of previous SARS-CoV-2 infection history, as well as clinical presentation during the acute phase and long-term symptoms from 4 to 12 weeks following infection. Furthermore, serum samples were collected from children with confirmed history of SARS-CoV-2 infection for serological testing of neutralizing antibodies. Results: The study recruited a total of 2,001 children aged 0-17 years who had previously tested positive for SARS-CoV-2 through nucleic acid or antigen testing. Fever emerged as the predominant clinical manifestation in 1,902 (95.1%) individuals with body temperature ranging from 37.3 to 40.0°C. Respiratory symptoms were identified as secondary clinical manifestations, with cough being the most common symptom in 777 (38.8%) children, followed by sore throat (22.1%), nasal congestion (17.8%), and runnning nose (17.2%). Fatigue (21.6%), headache (19.8%) and muscle-joint pain (13.5%) were frequently reported systemic symptoms in children. The proportion of children with symptoms of SARS-CoV-2 infection varied across age groups. 1,100 (55.0%) children experienced persistent symptoms from 4 to 12 weeks post the acute phase of infection. Trouble concentrating (22.1%), cough (22.1%), and fatigue (12.1%) were frequently reported across age groups in the extended period. A limited number of children exhibited cardiovascular symptoms with chest tightness, tachycardia, and chest pain reported by 3.5%, 2.5%, and 1.8% of children, respectively. Among 472 children aged 3-5 years, 208 children had received two doses of SARS-CoV-2 vaccine at least 6 months prior to infection, and no association was found between the incidence of long-term COVID and pre-infection vaccination statuses among the 3-5 years age groups (χ2 = 1.136, P = 0.286). Conclusions: In children aged 0-17 years infected with SARS-CoV-2 Omicron variant, fever was the primary clinical manifestation in the acute phase, followed by respiratory symptoms, systemic non-specific and digestive presentations. In particular, respiratory and digestive system symptoms were more frequent in children aged above 6 years. Regarding the long-term symptoms from 4 to 12 weeks post-infection, the most common presentations were concentrating difficulty, cough, and fatigue. The incidence of persistent symptoms of SARS-CoV-2 did not exhibit a significant correlation with vaccination status, which was attributed to the waning efficacy of the vaccine-induced humoral immune response after 6 months.

7.
Int J Colorectal Dis ; 39(1): 45, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38563889

RESUMEN

BACKGROUND: Depression and anxiety are common mental disorders in patients with colorectal cancer (CRC); however, it remains unclear whether they are related to cancer mortality. METHOD: Based on a systematic literature search, 12 eligible studies involving 26,907 patients with CRC were included in this study. RESULTS: Univariate analysis revealed that anxiety was associated with an all-cause mortality rate of 1.42 (1.02, 1.96), whereas multivariate analysis revealed that anxiety was not associated with an all-cause mortality rate of 0.73 (0.39, 1.36). In univariate and multivariate analyses, depression was associated with all-cause mortality rates of 1.89 (1.68, 2.13) and 1.62 (1.27, 2.06), respectively, but not with the cancer-associated mortality rate of 1.16 (0.91, 1.48) in multivariate analyses. Multivariate subgroup analysis of depression and all-cause mortality showed that younger age (≤65 years), being diagnosed with depression/anxiety after a confirmed cancer diagnosis, and shorter follow-up time (<5 years) were associated with poor prognosis. CONCLUSIONS: Our study emphasizes the key roles of depression and anxiety as independent factors for predicting the survival of patients with CRC. However, owing to the significant heterogeneity among the included studies, the results should be interpreted with caution. Early detection and effective treatment of depression and anxiety in patients with CRC have public health and clinical significance.


Asunto(s)
Ansiedad , Neoplasias Colorrectales , Depresión , Humanos , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/complicaciones , Neoplasias Colorrectales/psicología , Depresión/complicaciones , Ansiedad/complicaciones , Pronóstico , Análisis Multivariante , Anciano , Persona de Mediana Edad , Femenino , Masculino
8.
Breast Cancer Res ; 26(1): 37, 2024 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-38454442

RESUMEN

Increasing evidence shows the oncogenic function of FAM83D in human cancer, but how FAM83D exerts its oncogenic function remains largely unclear. Here, we investigated the importance of FAM83D/FBXW7 interaction in breast cancer (BC). We systematically mapped the FBXW7-binding sites on FAM83D through a comprehensive mutational analysis together with co-immunoprecipitation assay. Mutations at the FBXW7-binding sites on FAM83D led to that FAM83D lost its capability to promote the ubiquitination and proteasomal degradation of FBXW7; cell proliferation, migration, and invasion in vitro; and tumor growth and metastasis in vivo, indicating that the FBXW7-binding sites on FAM83D are essential for its oncogenic functions. A meta-evaluation of FAM83D revealed that the prognostic impact of FAM83D was independent on molecular subtypes. The higher expression of FAM83D has poorer prognosis. Moreover, high expression of FAM83D confers resistance to chemotherapy in BCs, which is experimentally validated in vitro. We conclude that identification of FBXW7-binding sites on FAM83D not only reveals the importance for FAM83D oncogenic function, but also provides valuable insights for drug target.


Asunto(s)
Neoplasias de la Mama , Proteínas de Ciclo Celular , Humanos , Femenino , Proteína 7 que Contiene Repeticiones F-Box-WD/genética , Proteína 7 que Contiene Repeticiones F-Box-WD/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Pronóstico , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo
9.
Sci Rep ; 14(1): 6814, 2024 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-38514736

RESUMEN

The present study aims to assess the treatment outcome of patients with diabetes and tuberculosis (TB-DM) at an early stage using machine learning (ML) based on electronic medical records (EMRs). A total of 429 patients were included at Chongqing Public Health Medical Center. The random-forest-based Boruta algorithm was employed to select the essential variables, and four models with a fivefold cross-validation scheme were used for modeling and model evaluation. Furthermore, we adopted SHapley additive explanations to interpret results from the tree-based model. 9 features out of 69 candidate features were chosen as predictors. Among these predictors, the type of resistance was the most important feature, followed by activated partial throm-boplastic time (APTT), thrombin time (TT), platelet distribution width (PDW), and prothrombin time (PT). All the models we established performed above an AUC 0.7 with good predictive performance. XGBoost, the optimal performing model, predicts the risk of treatment failure in the test set with an AUC 0.9281. This study suggests that machine learning approach (XGBoost) presented in this study identifies patients with TB-DM at higher risk of treatment failure at an early stage based on EMRs. The application of a convenient and economy EMRs based on machine learning provides new insight into TB-DM treatment strategies in low and middle-income countries.


Asunto(s)
Diabetes Mellitus , Humanos , Comorbilidad , Insuficiencia del Tratamiento , Registros Electrónicos de Salud , Aprendizaje Automático
10.
Int J Biol Macromol ; 267(Pt 1): 131150, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38556236

RESUMEN

Gut microbial ß-glucuronidases (gmß-GUS) played crucial roles in regulating a variety of endogenous substances and xenobiotics on the circulating level, thus had been recognized as key modulators of drug toxicity and human diseases. Inhibition or inactivation of gmß-GUS enzymes has become a promising therapeutic strategy to alleviate drug-induced intestinal toxicity. Herein, the Rhodiola crenulata extract (RCE) was found with potent and broad-spectrum inhibition on multiple gmß-GUS enzymes. Subsequently, the anti-gmß-GUS activities of the major constituents in RCE were tested and the results showed that 1,2,3,4,6-penta-O-galloyl-ß-d-glucopyranose (PGG) acted as a strong and broad-spectrum inhibitor on multiple gmß-GUS (including EcGUS, CpGUS, SaGUS, and EeGUS). Inhibition kinetic assays demonstrated that PGG effectively inhibited four gmß-GUS in a non-competitive manner, with the Ki values ranging from 0.12 µM to 1.29 µM. Docking simulations showed that PGG could tightly bound to the non-catalytic sites of various gmß-GUS, mainly via hydrogen bonding and aromatic interactions. It was also found that PGG could strongly inhibit the total gmß-GUS activity in mice feces, with the IC50 value of 1.24 µM. Collectively, our findings revealed that RCE and its constituent PGG could strongly inhibit multiple gmß-GUS enzymes, suggesting that RCE and PGG could be used for alleviating gmß-GUS associated enterotoxicity.


Asunto(s)
Inhibidores Enzimáticos , Microbioma Gastrointestinal , Simulación del Acoplamiento Molecular , Rhodiola , Rhodiola/química , Animales , Ratones , Microbioma Gastrointestinal/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Medicina Tradicional Tibetana , Cinética , Masculino
11.
J Biotechnol ; 385: 65-74, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38503366

RESUMEN

Ethyl carbamate (EC), a multisite carcinogenic compound, is naturally produced from urea and ethanol in alcoholic beverages. In order to reduce the content of EC in wine, the accumulation of arginine in Saccharomyces cerevisiae was regulated by genetic modifying genes involved in arginine transport and synthesis pathways to reduce the production of urea. Knockout of genes encoding arginine permease (Can1p) and amino acid permease (Gap1p) on the cell membrane as well as argininosuccinate synthase (Arg1) respectively resulted in a maximum reduction of 66.88% (9.40 µg/L) in EC, while overexpressing the gene encoding amino acid transporter (Vba2) reduced EC by 52.94% (24.13 µg/L). Simultaneously overexpressing Vba2 and deleting Arg1 showed the lowest EC production with a decrease of 68% (7.72 µg/L). The yield of total higher alcohols of the mutants all decreased compared with that of the original strain. Comprehensive consideration of flavor compound contents and sensory evaluation results indicated that mutant YG21 obtained by deleting two allele coding Gap1p performed best in must fermentation of Cabernet Sauvignon with the EC content low to 9.40 µg/L and the contents of total higher alcohols and esters of 245.61 mg/L and 41.71 mg/L respectively. This study has provided an effective strategy for reducing the EC in wine.


Asunto(s)
Proteínas de Saccharomyces cerevisiae , Vino , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Vino/análisis , Uretano/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Arginina/metabolismo , Etanol/metabolismo , Urea/metabolismo , Fermentación
12.
Plant Commun ; 5(6): 100849, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38384133

RESUMEN

Brassinosteroids (BRs) are a class of phytohormones that regulate plant growth and development. In previous studies, we cloned and identified PROTEIN PHOSPHATASE WITH KELCH-LIKE1 (OsPPKL1) as the causal gene for the quantitative trait locus GRAIN LENGTH3 (qGL3) in rice (Oryza sativa). We also showed that qGL3/OsPPKL1 is mainly located in the cytoplasm and nucleus and negatively regulates BR signaling and grain length. Because qGL3 is a negative regulator of BR signaling, its turnover is critical for rapid response to changes in BRs. Here, we demonstrate that qGL3 interacts with the WD40-domain-containing protein WD40-REPEAT PROTEIN48 (OsWDR48), which contains a nuclear export signal (NES). The NES signal is crucial for the cytosolic localization of OsWDR48 and also functions in the self-turnover of qGL3. We show that OsWDR48 physically interacts with and genetically acts through qGL3 to modulate BR signaling. Moreover, qGL3 may indirectly promote the phosphorylation of OsWDR48 at the Ser-379 and Ser-386 sites. Substitutions of both phosphorylation sites in OsWDR48 to non-phosphorylatable alanine enhanced the strength of the OsWDR48-qGL3 interaction. Furthermore, we found that brassinolide can promote the accumulation of non-phosphorylated OsWDR48, leading to strong interaction intensity between qGL3 and OsWDR48. Taken together, our results show that OsWDR48 facilitates qGL3 retention and induces degradation of qGL3 in the cytoplasm. These findings suggest that qGL3 self-modulates its turnover by binding to OsWDR48 to regulate its cytoplasmic localization and stability, leading to efficient orchestration of BR signal transduction in rice.


Asunto(s)
Brasinoesteroides , Oryza , Proteínas de Plantas , Transducción de Señal , Oryza/genética , Oryza/metabolismo , Brasinoesteroides/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Fosfoproteínas Fosfatasas/metabolismo , Fosfoproteínas Fosfatasas/genética , Regulación de la Expresión Génica de las Plantas , Fosforilación
13.
Sci Rep ; 14(1): 3138, 2024 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-38326459

RESUMEN

Scrub typhus may be one of the world's most prevalent, neglected and serious, but easily treatable, febrile diseases. It has become a significant potential threat to public health in China. In this study we used national disease surveillance data to analyze the incidence and spatial-temporal distribution of scrub typhus in mainland China during 1952-1989 and 2006-2018. Descriptive epidemiological methods and spatial-temporal epidemiological methods were used to investigate the epidemiological trends and identify high-risk regions of scrub typhus infection. Over the 51-year period, a total of 182,991 cases and 186 deaths were notified. The average annual incidence was 0.13 cases/100,000 population during 1952-1989. The incidence increased sharply from 0.09/100,000 population in 2006 to 1.93/100,000 population in 2018 and then exponentially increased after 2006. The incidence was significantly higher in females than males (χ2 = 426.32, P < 0.001). Farmers had a higher incidence of scrub typhus than non-farmers (χ2 = 684.58, P < 0.001). The majority of cases each year were reported between July and November with peak incidence occurring during October each year. The trend surface analysis showed that the incidence of scrub typhus increased gradually from north to south, and from east and west to the central area. The spatial autocorrelation analysis showed that a spatial positive correlation existed in the prevalence of scrub typhus on a national scale, which had the characteristic of aggregated distribution (I = 0.533, P < 0.05). LISA analysis showed hotspots (High-High) were primarily located in the southern and southwestern provinces of China with the geographical area expanding annually. These findings provide scientific evidence for the surveillance and control of scrub typhus which may contribute to targeted strategies and measures for the government.


Asunto(s)
Tifus por Ácaros , Masculino , Femenino , Humanos , Tifus por Ácaros/epidemiología , Estaciones del Año , Análisis Espacial , Incidencia , China/epidemiología
14.
Environ Res ; 246: 118151, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38191045

RESUMEN

Nitric acid, an important basic chemical raw material, plays an important role in promoting the development of national economy. However, such liquid hazardous chemicals are easy to cause accidental leakage during production, transportation, storage and use. The high concentration and corrosive toxic gas generated from decomposition shows tremendous harm to the surrounding environment and human life safety. Therefore, how to inhibit the volatilization of nitric acid and effectively control and block the generation of the toxic gas in the first time are the key to deal with the nitric acid leakage accident. Herein, a new method of molecular film obstruction is proposed to inhibit the nitric acid volatilization. The molecular film inhibitor spontaneously spread and form an insoluble molecular film on the gas-liquid interface, changing the state of nitric acid liquid surface and inhibiting the volatilization on the molecular scale. The inhibition rate up to 96% can be achieved below 45 °C within 400 min. Cluster structure simulation and energy barrier calculation is performed to elucidate the inhibition mechanism. Theoretical analysis of energy barrier shows that the specific resistance of the inhibitor significantly increased to 460 s·cm-1 at 45 °C, and the generated energy barrier is about 17,000 kJ·mol-1, which is much higher than the maximum energy required for nitric acid volatilization of 107.97 kJ·mol-1. The molecular film obstruction strategy can effectively inhibit the volatilization of nitric acid. This strategy paves the way for preventing the volatilization of liquid hazardous chemicals in accidental leakage treatment.


Asunto(s)
Modelos Teóricos , Ácido Nítrico , Humanos , Volatilización , Sustancias Peligrosas/toxicidad
15.
Nat Commun ; 15(1): 602, 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38238334

RESUMEN

Plants usually produce defence metabolites in non-active forms to minimize the risk of harm to themselves and spatiotemporally activate these defence metabolites upon pathogen attack. This so-called two-component system plays a decisive role in the chemical defence of various plants. Here, we discovered that Panax notoginseng, a valuable medicinal plant, has evolved a two-component chemical defence system composed of a chloroplast-localized ß-glucosidase, denominated PnGH1, and its substrates 20(S)-protopanaxadiol ginsenosides. The ß-glucosidase and its substrates are spatially separated in cells under physiological conditions, and ginsenoside hydrolysis is therefore activated only upon chloroplast disruption, which is caused by the induced exoenzymes of pathogenic fungi upon exposure to plant leaves. This activation of PnGH1-mediated hydrolysis results in the production of a series of less-polar ginsenosides by selective hydrolysis of an outer glucose at the C-3 site, with a broader spectrum and more potent antifungal activity in vitro and in vivo than the precursor molecules. Furthermore, such ß-glucosidase-mediated hydrolysis upon fungal infection was also found in the congeneric species P. quinquefolium and P. ginseng. Our findings reveal a two-component chemical defence system in Panax species and offer insights for developing botanical pesticides for disease management in Panax species.


Asunto(s)
Ginsenósidos , Panax , Plantas Medicinales , Ginsenósidos/farmacología , Ginsenósidos/química , Panax/química , Panax/metabolismo , beta-Glucosidasa/metabolismo , Plantas Medicinales/metabolismo , Extractos Vegetales/química
16.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-955480

RESUMEN

Although herbal medicines(HMs)are widely used in the prevention and treatment of obesity and obesity-associated disorders,the key constituents exhibiting anti-obesity activity and their molecular mechanisms are poorly understood.Recently,we assessed the inhibitory potentials of several HMs against human pancreatic lipase(hPL,a key therapeutic target for human obesity),among which the root-extract of Rhodiola crenulata(ERC)showed the most potent anti-hPL activity.In this study,we adopted an integrated strategy,involving bioactivity-guided fractionation techniques,chemical profiling,and biochemical assays,to identify the key anti-hPL constituents in ERC.Nine ERC fractions(retention time=12.5-35 min),obtained using reverse-phase liquid chromatography,showed strong anti-hPL activity,while the major constituents in these bioactive fractions were subsequently identified using liquid chromatography-quadrupole time-of-flight mass spectrometry(LC-Q-TOF-MS/MS).Among the identified ERC constituents,1,2,3,4,6-penta-O-galloyl-β-D-glucopyranose(PGG)and catechin gallate(CG)showed the most potent anti-hPL activity,with pIC50 values of 7.59±0.03 and 7.68±0.23,respectively.Further investigations revealed that PGG and CG potently inhibited hPL in a non-competitive manner,with inhibition constant(Ki)values of 0.012 and 0.082 μM,respectively.Collectively,our integrative analyses enabled us to efficiently identify and characterize the key anti-obesity constituents in ERC,as well as to elucidate their anti-hPL mechanisms.These findings provide convincing evidence in support of the anti-obesity and lipid-lowering properties of ERC.

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