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1.
J Org Chem ; 89(5): 3481-3490, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38381857

RESUMEN

We present a direct δ-amination reaction of sp3 C-H bonds, employing molecular iodine (I2) as the sole oxidant under transition-metal-free conditions. This remote C-H functionalization approach is operationally simple and provides facile, efficient access to pyrrolidines and related heterocyclic derivatives from readily accessible substrates.

2.
Clin Gerontol ; : 1-13, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38819173

RESUMEN

OBJECTIVES: Although the association between sleep disorders and frailty has been well established, little is known about the cognitive appraisal mechanisms underlying this association. Building on the transactional theory of stress and coping, this study explores the role of self-efficacy and coping style in the association between sleep quality and frailty among community-dwelling older adults. METHODS: In this cross-sectional study, 585 community-dwelling older adults were investigated using the Pittsburgh Sleep Quality Index, Tilburg Frailty Indicator, General Self-Efficacy Scale, and Simplified Coping Style Questionnaire. Descriptive statistics and hierarchical regression were performed. A moderated mediation model was established using the PROCESS macro. RESULTS: Poor sleep quality affects frailty directly (B = 0.193, p < .01) and indirectly via self-efficacy (B = 0.063, p < .01). The negative impact of poor sleep on frailty through self-efficacy was moderated by both positive and negative coping style (index = -0.007). The moderating effect was stronger when participants' negative coping tendencies increased. CONCLUSIONS: Poor sleep quality indirectly influences frailty by modifying self-efficacy. Effective coping strategies can help attenuate this association. CLINICAL IMPLICATIONS: Timely sleep assessment and tailored strategies such as psychoeducational programs and targeted coping skills training may be beneficial for preventing frailty in older adults.

3.
Curr Issues Mol Biol ; 45(9): 7110-7129, 2023 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-37754234

RESUMEN

Melon (Cucumis melo L.) is an economically important Cucurbitaceae crop grown around the globe. The sweetness of melon is a significant factor in fruit quality and consumer appeal, and the soluble solids content (SSC) is a key index of melon sweetness. In this study, 146 recombinant inbred lines (RILs) derived from two oriental melon materials with different levels of sweetness containing 1427 bin markers, and 213 melon accessions containing 1,681,775 single nucleotide polymorphism (SNP) markers were used to identify genomic regions influencing SSC. Linkage mapping detected 10 quantitative trait loci (QTLs) distributed on six chromosomes, seven of which were overlapped with the reported QTLs. A total of 211 significant SNPs were identified by genome-wide association study (GWAS), 138 of which overlapped with the reported QTLs. Two new stable, co-localized regions on chromosome 3 were identified by QTL mapping and GWAS across multiple environments, which explained large phenotypic variance. Five candidate genes related to SSC were identified by QTL mapping, GWAS, and qRT-PCR, two of which were involved in hydrolysis of raffinose and sucrose located in the new stable loci. The other three candidate genes were involved in raffinose synthesis, sugar transport, and production of substrate for sugar synthesis. The genomic regions and candidate genes will be helpful for molecular breeding programs and elucidating the mechanisms of sugar accumulation.

4.
J Org Chem ; 88(2): 1061-1074, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36630199

RESUMEN

An iodine-mediated intramolecular sp3 C-H amination reaction producing quinazolinone-fused polycyclic skeletons from 2-aminobenzamide precursors is reported. This reaction does not use transition metals, has a broad substrate scope, and can be used on a gram scale. Under the optimal reaction conditions, a variety of quinazolinone-fused tetrahydroisoquinolines and derivatives of Rutaecarpine were synthesized from readily accessible compounds. The reaction proceeds well with crude 2-aminobenzamide derivatives, allowing for the synthesis of the products from simple 2-aminobenzoic acids and tetrahydroisoquinolines without purification of the 2-aminobenzamide intermediates. Preliminary biological experiments have identified Cereblon (CRBN) inhibitory activity and relevant anti-myeloma medicinal properties in some of these polycyclic products.

5.
J Org Chem ; 88(13): 8751-8760, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37305921

RESUMEN

A new synthetic strategy for direct C(sp3)-H amination of carbonyl compounds at their α-carbon has been established employing molecular iodine and nitrogen-directed oxidative umpolung. In this transformation, iodine acts not only as an iodinating reagent but also as a Lewis acid catalyst, and both the nitrogen-containing moiety and the carbonyl group in the substrate play important roles. This synthetic approach is applicable to a broad variety of carbonyl substrates, including esters, ketones, and amides. Its features also include no requirement for transition metals, mild reaction conditions, short reaction times, and gram-scale synthesis.


Asunto(s)
Yodo , Nitrógeno , Aminación , Nitrógeno/química , Oxidación-Reducción , Estrés Oxidativo
6.
Oecologia ; 201(1): 173-182, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36512080

RESUMEN

Changes in the amount and timing of precipitation may affect plant species coexistence. However, little is known about how these changes in precipitation structure plant communities. Here, we conducted a 6-year field precipitation manipulation experiment in the semi-arid steppe of Inner Mongolia, China, to assess the importance of species extinction and colonization in community assembly by incorporating information on phylogenetic and functional relatedness. Our results demonstrated that the decline in plant species richness under decreasing precipitation in the late and entire growing season could be attributed to a decrease in species colonization and an increase in species loss, respectively. The increase in species richness under increasing precipitation in the late growing season was mainly caused by increases in colonizing species. The loss of species that were more closely related to other residents under decreasing precipitation in the late growing season did not alter patterns of phylogenetic overdispersion, and the colonization of species that were more distantly related to residents under increasing precipitation in the late growing season shifted functional relatedness from clustering to randomness. Increasing precipitation may weaken the strength of environmental filtering induced by water stress in this semi-arid steppe and thus increase the probability of successful colonization of functionally dissimilar species relative to residents. Our study suggests that incorporating information on the functional and phylogenetic relatedness of locally lost resident species and the colonization of new species into analyses of community assembly processes can provide new insights into the general responses of plant communities to global change.


Asunto(s)
Plantas , Lluvia , Filogenia , Estaciones del Año , China , Pradera
7.
Acta Pharmacol Sin ; 44(10): 1989-2003, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37268711

RESUMEN

Patients with rheumatoid arthritis (RA) have a much higher incidence of cardiac dysfunction, which contributes to the high mortality rate of RA despite anti-arthritic drug therapy. In this study, we investigated dynamic changes in cardiac function in classic animal models of RA and examined the potential effectors of RA-induced heart failure (HF). Collagen-induced arthritis (CIA) models were established in rats and mice. The cardiac function of CIA animals was dynamically monitored using echocardiography and haemodynamics. We showed that cardiac diastolic and systolic dysfunction occurred in CIA animals and persisted after joint inflammation and that serum proinflammatory cytokine (IL-1ß, TNF-α) levels were decreased. We did not find evidence of atherosclerosis (AS) in arthritic animals even though cardiomyopathy was significant. We observed that an impaired cardiac ß1AR-excitation contraction coupling signal was accompanied by sustained increases in blood epinephrine levels in CIA rats. Furthermore, serum epinephrine concentrations were positively correlated with the heart failure biomarker NT-proBNP in RA patients (r2 = +0.53, P < 0.0001). In CIA mice, treatment with the nonselective ßAR blocker carvedilol (2.5 mg·kg-1·d-1, for 4 weeks) or the specific GRK2 inhibitor paroxetine (2.5 mg·kg-1·d-1, for 4 weeks) effectively rescued heart function. We conclude that chronic and persistent ß-adrenergic stress in CIA animals is a significant contributor to cardiomyopathy, which may be a potential target for protecting RA patients against HF.


Asunto(s)
Artritis Experimental , Artritis Reumatoide , Cardiomiopatías , Insuficiencia Cardíaca , Humanos , Ratones , Ratas , Animales , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/inducido químicamente , Roedores , Adrenérgicos/efectos adversos , Artritis Reumatoide/tratamiento farmacológico , Citocinas , Insuficiencia Cardíaca/tratamiento farmacológico , Epinefrina/efectos adversos
8.
Appl Microbiol Biotechnol ; 107(15): 4947-4959, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37306707

RESUMEN

Infectious African swine fever virus (ASFV) can cause the spread and morbidity of African swine fever, while the inactivated virus cannot. When they are not distinguished separately, the detection results will lack authenticity and cause unnecessary panic and detection cost. The detection technology based on cell culture is complex, high-cost, and time-consuming in practice, which is not conducive to the rapid detection of infectious ASFV. In this study, a propidium monoazide (PMA) qPCR detection method for rapid diagnosis of infectious ASFV was constructed. Parameters of PMA concentration, light intensity, and lighting time were under strict safety verification and comparative analysis for optimization. The results determined that the optimal condition for PMA to pretreat ASFV was the final concentration of PMA 100 µM. The light intensity was 40 W, the light duration was 20 min, the target fragment size of the optimal primer probe was 484 bp, and its detection sensitivity for infectious ASFV was 101.28 HAD50/mL. In addition, the method was innovatively applied to the rapid evaluation of disinfection effect. When ASFV concentration was less than 102.28 HAD50/mL, the method could still be effective for the evaluation of thermal inactivation effect, and the evaluation ability of chlorine-containing disinfectants was better, and the applicable concentration could reach 105.28 HAD50/mL. It is worth mentioning that this method can not only reflect whether the virus is inactivated, but also indirectly reflect the degree of damage to viral nucleic acid caused by disinfectants. In conclusion, the PMA-qPCR constructed in this study can be applied to laboratory diagnosis, disinfection effect evaluation, drug development, and other aspects of infectious ASFV and can provide new technical support for effective prevention and control of ASF. KEY POINTS: • A rapid detection method for infectious ASFV was developed • Provide a new scheme for rapid evaluation of disinfection effect of chlorine-containing disinfectants • PMA-qPCR can simultaneously show the survival status of the virus and the damage of nucleic acid.


Asunto(s)
Virus de la Fiebre Porcina Africana , Fiebre Porcina Africana , Desinfectantes , Porcinos , Animales , Fiebre Porcina Africana/prevención & control , Desinfección/métodos , Cloro/farmacología , Desinfectantes/farmacología
9.
Mikrochim Acta ; 190(2): 75, 2023 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-36700977

RESUMEN

Benzotriazole UV stabilizers (BUVSs) are a class of emerging contaminants of concern; the development of rapid and convenient monitoring method for these trace-level pollutants in waters is of crucial significance in environmental science. Here, a novel magnetic flower-like molybdenum disulfide/cobalt ferrite nanocomposite (MoS2/CoFe2O4) was synthesized by hydrothermal reaction. Compared with the conventional Fe3O4-based magnetic composites, the proposed material just required a minimum consumption of Co/Fe towards the equivalent of MoS2 while providing superior magnetization performance. Taking advantages of high adsorption capacity, extraordinary stability, and repeatability in construction, MoS2/CoFe2O4 was applied to the extraction to BUVSs. The enrichment factors of three BUVSs were in the range 164-193 when 20 mL of environmental water sample was loaded on 40 mg of the adsorbent. MoS2/CoFe2O4 could be regenerated and recycled at least 10 cycles of adsorption/desorption with recoveries of 80.1-111%. The method of MoS2/CoFe2O4-based extraction coupled with high-performance liquid chromatography-variable wavelength detector was applied to the monitoring of BUVSs in seawater, lake water, and wastewater, which gave detection limits (S/N = 3) of 0.023-0.030 ng·mL-1 and recoveries of 80.1-110%. The intra-day and inter-day precisions (relative standard deviation, RSDs, n = 3) were in the range 1.6-7.5% and 3.2-11.5%, respectively. The approach is an alternative for efficient and sensitive extraction and determination of trace-level environmental pollutants in waters.

10.
Sensors (Basel) ; 23(13)2023 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-37447949

RESUMEN

Traditional path planning is mainly utilized for path planning in discrete action space, which results in incomplete ship navigation power propulsion strategies during the path search process. Moreover, reinforcement learning experiences low success rates due to its unbalanced sample collection and unreasonable design of reward function. In this paper, an environment framework is designed, which is constructed using the Box2D physics engine and employs a reward function, with the distance between the agent and arrival point as the main, and the potential field superimposed by boundary control, obstacles, and arrival point as the supplement. We also employ the state-of-the-art PPO (Proximal Policy Optimization) algorithm as a baseline for global path planning to address the issue of incomplete ship navigation power propulsion strategy. Additionally, a Beta policy-based distributed sample collection PPO algorithm is proposed to overcome the problem of unbalanced sample collection in path planning by dividing sub-regions to achieve distributed sample collection. The experimental results show the following: (1) The distributed sample collection training policy exhibits stronger robustness in the PPO algorithm; (2) The introduced Beta policy for action sampling results in a higher path planning success rate and reward accumulation than the Gaussian policy at the same training time; (3) When planning a path of the same length, the proposed Beta policy-based distributed sample collection PPO algorithm generates a smoother path than traditional path planning algorithms, such as A*, IDA*, and Dijkstra.


Asunto(s)
Algoritmos , Suplementos Dietéticos , Aprendizaje , Distribución Normal , Políticas
11.
Molecules ; 28(13)2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37446737

RESUMEN

A one-step cobaltous chloride (CoCl2) molten salt method was employed to prepare multilayer MXene-Ti3C2/Co materials with further ultrasonic treatment to acquire single-layer MXene-Ti3C2/Co nanosheets (NSs). MXene-Ti3C2/Co NSs were characterized, and their enzyme-like activities were investigated. Under the catalysis of MXene-Ti3C2/Co NSs, 3,3',5,5'-tetramethylbenzidine (TMB) could be oxidized by H2O2, with the color changing from colorless to blue. The affinity of MXene-Ti3C2/Co NSs to H2O2 and TMB was better than that of nanozymes reported in previous studies. The MXene-Ti3C2/Co NSs were used for the colorimetric determination of H2O2/glucose, with limits of detection (LODs) of 0.033 mM and 1.7 µM, respectively. MXene-Ti3C2/Co NSs embedded in sodium alginate (SA) hydrogel were used to construct a sensor platform. The digital pictures combined with a smartphone-installed app (color recognizer) could be used to analyze RGB values for colorimetric detection of glucose in beverages. This point-of-care testing platform has the advantages of cost-effectiveness and good transferability, with the potential to realize quick, intelligent and on-site detection.


Asunto(s)
Glucosa , Teléfono Inteligente , Titanio , Peróxido de Hidrógeno/análisis , Hidrogeles , Bebidas
12.
Environ Geochem Health ; 45(5): 2263-2275, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35925433

RESUMEN

Exposure to metals is associated with lung function decline. However, limited data are available about effects of co-exposure of metals on lung function. Additionally, the mechanism of the association between metals and lung function remains unclear. We conducted a longitudinal panel study in 2017-2018 among 45 healthy college students. Urinary 15 metals, lung function, biomarkers of oxidative stress and inflammation of participants were measured. Linear mixed effect (LME) and Bayesian kernel machine regression (BKMR) models were applied to explore the associations of urinary metals and mixture with lung function. Furthermore, we analyzed the mediating effect of biomarkers in the association between urinary metals and lung function. LME models showed the negative associations of aluminum (Al), vanadium (V), manganese (Mn), cobalt (Co), nickel (Ni), cadmium (Cd) or antimony (Sb) with Forced vital capacity (FVC), and V, Co, Ni, and Sb with Forced expiratory volume in one second (FEV1). BKMR models indicated the overall effect of metals mixture was negatively associated with FEV1 and FVC; urinary Sb was identified as the major contributor to decreased FVC and FEV1. Urinary 8-hydroxydeoxyguanosine mediated the association of Al, Mn, or Sb with FVC and the relationship of V with FEV1. The results revealed the longitudinal dose-response relationships of urinary metals with pulmonary function among healthy adults. Oxidative stress may be the underlying mechanisms of metals exposure associated with decreased lung function. Due to the small sample size, the interpretation of the results of this study should be cautious, and more studies are needed to verify the findings of this study.


Asunto(s)
Pulmón , Metales , Adulto , Humanos , Teorema de Bayes , Metales/toxicidad , Cobalto/toxicidad , Biomarcadores , Manganeso , Níquel/toxicidad , Aluminio , Estrés Oxidativo
13.
Zhongguo Zhong Yao Za Zhi ; 48(14): 3882-3889, 2023 Jul.
Artículo en Zh | MEDLINE | ID: mdl-37475080

RESUMEN

This study aims to explore the effect of Xiaoxuming Decoction on synaptic plasticity in rats with acute cerebral ischemia-reperfusion. A rat model of cerebral ischemia-reperfusion injury was established by middle cerebral artery occlusion(MCAO). Rats were randomly assigned into a sham group, a MCAO group, and a Xiaoxuming Decoction(60 g·kg~(-1)·d~(-1)) group. The Longa score was rated to assess the neurological function of rats with cerebral ischemia for 1.5 h and reperfusion for 24 h. The 2,3,5-triphenyltetrazolium chloride(TTC) staining and hematoxylin-eosin(HE) staining were employed to observe the cerebral infarction and the pathological changes of brain tissue after cerebral ischemia, respectively. Transmission electron microscopy was employed to detect the structural changes of neurons and synapses in the ischemic penumbra, and immunofluorescence, Western blot to determine the expression of synaptophysin(SYN), neuronal nuclei(NEUN), and postsynaptic density 95(PSD95) in the ischemic penumbra. The experimental results showed that the modeling increased the Longa score and led to cerebral infarction after 24 h of ischemia-reperfusion. Compared with the model group, Xiaoxuming Decoction intervention significantly decreased the Longa score and reduced the formation of cerebral infarction area. The modeling led to the shrinking and vacuolar changes of nuclei in the brain tissue, disordered cell arrangement, and severe cortical ischemia-reperfusion injury, while the pathological damage in the Xiaoxuming Decoction group was mild. The modeling blurred the synaptic boundaries and broadened the synaptic gap, while such changes were recovered in the Xiaoxuming Decoction group. The modeling decreased the fluorescence intensity of NEUN and SYN, while the intensity in Xiaoxuming Decoction group was significantly higher than that in the model group. The expression of SYN and PSD95 in the ischemic penumbra was down-regulated in the model group, while such down-regulation can be alleviated by Xiaoxuming Decoction. In summary, Xiaoxuming Decoction may improve the synaptic plasticity of ischemic penumbra during acute cerebral ischemia-reperfusion by up-regulating the expression of SYN and PSD95.


Asunto(s)
Isquemia Encefálica , Daño por Reperfusión , Ratas , Animales , Ratas Sprague-Dawley , Isquemia Encefálica/tratamiento farmacológico , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/metabolismo , Infarto de la Arteria Cerebral Media , Plasticidad Neuronal , Reperfusión
14.
Zhongguo Zhong Yao Za Zhi ; 48(21): 5830-5837, 2023 Nov.
Artículo en Zh | MEDLINE | ID: mdl-38114179

RESUMEN

This study investigated the effect of Xiaoxuming Decoction(XXMD) on the activation of astrocytes after cerebral ischemia/reperfusion(I/R) injury. The model of cerebral IR injury was established using the middle cerebral artery occlusion method. Fluorocitrate(FC), an inhibitor of astrocyte activation, was applied to inhibit astrocyte activation. Rats were randomly divided into a sham group, a model group, a XXMD group, a XXMD+FC group, and a XXMD+Vehicle group. Neurobehavioral changes at 24 hours after cerebral IR injury, cerebral infarction, histopathological changes observed through HE staining, submicroscopic structure of astrocytes observed through transmission electron microscopy, fluorescence intensity of glial fibrillary acidic protein(GFAP) and thrombospondin 1(TSP1) measured through immunofluorescence, and expression of GFAP and TSP1 in brain tissue measured through Western blot were evaluated in rats from each group. The experimental results showed that neurobehavioral scores and cerebral infarct area significantly increased in the model group. The XXMD group, the XXMD+FC group, and the XXMD+Vehicle group all alleviated neurobehavioral changes in rats. The pathological changes in the brain were evident in the model group, while the XXMD group, the XXMD+FC group, and the XXMD+Vehicle group exhibited milder cerebral IR injury in rats. The submicroscopic structure of astrocytes in the model group showed significant swelling, whereas the XXMD group, the XXMD+FC group, and XXMD+Vehicle group protected the submicroscopic structure of astrocytes. The fluorescence intensity and protein expression of GFAP and TSP1 increased in the model group compared with those in the sham group. However, the XXMD group, the XXMD+FC group, and XXMD+Vehicle group all down-regulated the expression of GFAP and TSP1. The combination of XXMD and FC showed a more pronounced effect. These results indicate that XXMD can improve cerebral IR injury, possibly by inhibiting astrocyte activation and down-regulating the expression of GFAP and TSP1.


Asunto(s)
Isquemia Encefálica , Daño por Reperfusión , Ratas , Animales , Astrocitos , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/metabolismo , Encéfalo , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/metabolismo , Infarto de la Arteria Cerebral Media
15.
Sci Educ (Dordr) ; 32(3): 589-615, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35411127

RESUMEN

This study used the Latent Dirichlet Allocation (LDA) topic model to analyze pre-service teachers' views on the nature of science (NOS). This approach can be used to automate the classification of documents, and at the same time, the researcher does not need to deduce with a NOS framework prior to evaluation. Participants were 155 pre-service teachers studying at the Shandong Normal University in China. To gather our data, we used an open questionnaire, namely, the Views of Nature of Science Questionnaire-Form C (VNOS-C). LDA topic modeling was used to classify the document, which was divided into 12 topics. By comparing the LDA topic modeling results with the theoretical framework behind the VNOS-C questionnaire, we categorized these 12 topics into eight descriptive aspects of the NOS: The Empirical Nature of Scientific Knowledge, Observation, Inference, and Theoretical Entities in Science, Scientific Theories and Laws, The Theory-Laden Nature of Scientific Knowledge, The Social and Cultural Embeddedness of Scientific Knowledge, The Myth of The Scientific Method, The Tentative Nature of Scientific Knowledge, and The Nature of Scientific Theory. The results show that pre-service teachers usually hold naive or mixed views of the NOS. In addition, each aspect of NOS is not independent of each other but interrelated and influencing each other. In the future, more consideration can be given to the relationship between each aspect of NOS.

16.
Small ; 18(23): e2108124, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35434905

RESUMEN

Solid-state electrolytes (SSEs) have been thrust into the limelight for the revival of energy-dense lithium metal batteries, but still face the challenge of failure caused by the dendrite penetration. Mounting evidence indicates that dendrite penetration is related to the mechanical failure in SSEs, which calls for mechanical engineering to tackle this problem. This work reports a proof of concept that ion implantation induced surface compressive stress enables resistance in the dendrite penetration. A deterministic sequential multiple ion energies implantation is used to generate compressive stress, with implanted Xe ions distributed in a range of 160-600 Å from the surface. The symmetric lithium cells show that pellets with an implantation dose of 1013 Xe cm-2 exhibit stable stripping/plating cycles and extended lifespan, while a lower dose of 1012 Xe cm-2 cannot create sufficient stress to prevent dendrite penetration, and an excessive dose of 1014 Xe cm-2 leads to structural destruction and a decrease in stress. This improved performance is attributed to the induced surface compressive stress balanced over crystal grains, which is confirmed by grazing incidence diffraction techniques. The author's efforts demonstrate the usefulness of surface compressive stress to suppress dendrite penetration, offering more insight into rational stress-strain engineering as opposed to empirical optimization.


Asunto(s)
Litio , Xenón , Dendritas , Electrólitos , Iones
17.
Opt Express ; 30(4): 4718-4736, 2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35209447

RESUMEN

Determination of macroscale detonation parameters of energetic materials (EMs) in a safe and rapid way is highly desirable. However, traditional experimental methods suffer from tedious operation, safety hazards and high cost. Herein, we present a micro-scale approach for high-precision diagnosis of explosion parameters based on radiation spectra and dynamic analysis during the interaction between laser and EMs. The intrinsic natures of micro-explosion dynamics covering nanosecond to millisecond and chemical reactions in laser-induced plasma are revealed, which reveal a tight correlation between micro-detonation and macroscopic detonation based on laser-induced plasma spectra and dynamics combined with statistic ways. As hundreds to thousands of laser pulses ablate on seven typical tetrazole-based high-nitrogen compounds and ten single-compound explosives, macroscale detonation performance can be well estimated with a high-speed and high-accuracy way. Thereby, the detonation pressure and enthalpies of formation can be quantitatively determined by the laser ablation processes for the first time to our knowledge. These results enable us to diagnose the performance of EMs in macroscale domain from microscale domain with small-dose, low-cost and multiple parameters.

18.
Acta Pharmacol Sin ; 43(2): 401-416, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33859345

RESUMEN

Our previous study showed that chronic treatment with tumor necrosis factor-α (TNF-α) decreased cAMP concentration in fibroblast-like synoviocytes (FLSs) of collagen-induced arthritis (CIA) rats. In this study we investigated how TNF-α impairs cAMP homeostasis, particularly clarifying the potential downstream molecules of TNF-α and prostaglandin receptor 4 (EP4) signaling that would interact with each other. Using a cAMP FRET biosensor PM-ICUE3, we demonstrated that TNF-α (20 ng/mL) blocked ONO-4819-triggered EP4 signaling, but not Butaprost-triggered EP2 signaling in normal rat FLSs. We showed that TNF-α (0.02-20 ng/mL) dose-dependently reduced EP4 membrane distribution in normal rat FLS. TNF-α significantly increased TNF receptor 2 (TNFR2) expression and stimulated proliferation in human FLS (hFLS) via ecruiting TNF receptor-associated factor 2 (TRAF2) to cell membrane. More interestingly, we revealed that TRAF2 interacted with G protein-coupled receptor kinase (GRK2) in the cytoplasm of primary hFLS and helped to bring GRK2 to cell membrane in response of TNF-α stimulation, the complex of TRAF2 and GRK2 then separated on the membrane, and translocated GRK2 induced the desensitization and internalization of EP4, leading to reduced production of intracellular cAMP. Silencing of TRAF2 by siRNA substantially diminished TRAF2-GRK2 interaction, blocked the translocation of GRK2, and resulted in upregulated expression of membrane EP4 and intracellular cAMP. In CIA rats, administration of paroxetine to inhibit GRK2 effectively improved the symptoms and clinic parameters with significantly reduced joint synovium inflammation and bone destruction. These results elucidate a novel form of cross-talk between TNFR (a cytokine receptor) and EP4 (a typical G protein-coupled receptor) signaling pathways. The interaction between TRAF2 and GRK2 may become a potential new drug target for the treatment of inflammatory diseases.


Asunto(s)
Quinasa 2 del Receptor Acoplado a Proteína-G/metabolismo , Subtipo EP4 de Receptores de Prostaglandina E/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Sinoviocitos/efectos de los fármacos , Factor 2 Asociado a Receptor de TNF/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Animales , Artritis Experimental/metabolismo , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Ratas , Ratas Sprague-Dawley , Sinoviocitos/metabolismo
19.
Acta Biochim Biophys Sin (Shanghai) ; 54(9): 1278-1288, 2022 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-36082932

RESUMEN

Obesity has now surpassed malnutrition and infectious diseases as the most significant contributor to health problems worldwide. In particular, obesity is associated with several metabolic disorders, including hyperlipidemia, hepatic steatosis, and subfertility. Genipin (GNP), the aglycone of geniposide, is isolated from the extract of the traditional Chinese medicine Gardenia jasminoides Ellis and has been used in traditional oriental medicine against several inflammation-driven diseases. However, the effect and molecular mechanism of GNP on obesity-associated dyslipidemia and sperm dysfunction still need to be explored. In this study, we detect the effects of GNP on hyperlipidemia, hepatic lipid accumulation and sperm function using a high-fat diet (HFD)-induced obese mouse model. We find that obese mice treated with GNP show an improvement in body weight, serum triglyceride levels, serum hormone levels, serum inflammatory cytokines, hepatic steatosis and sperm function. At the molecular level, HFD/GNP diversely regulates the expression of miR-132 in a tissue-specific manner. miR-132 further targets and regulates the expression of SREBP-1c in liver cells, as well as the expressions of SREBP-1c and StAR in Leydig cells in the testis, thus modifying lipogenesis and steroidogenesis, respectively. Collectively, our data demonstrate that GNP shows a broad effect on the improvement of HFD-induced metabolic disorder and sperm dysfunction in male mice by tissue-specific regulation of miR-132. Our findings reveal the function GNP in ameliorating hepatic lipid metabolism and sperm function and suggest that this compound is a versatile drug to treat metabolic disorders.


Asunto(s)
Hígado Graso , Hiperlipidemias , Enfermedades Metabólicas , MicroARNs , Masculino , Animales , Ratones , Metabolismo de los Lípidos , Ratones Obesos , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Semen/metabolismo , Hígado/metabolismo , Hígado Graso/inducido químicamente , Hígado Graso/metabolismo , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Hiperlipidemias/metabolismo , Dieta Alta en Grasa/efectos adversos , Enfermedades Metabólicas/metabolismo , MicroARNs/metabolismo , Espermatozoides/metabolismo , Ratones Endogámicos C57BL
20.
Ecotoxicol Environ Saf ; 230: 113168, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34999341

RESUMEN

Exposure to polycyclic aromatic hydrocarbons (PAHs) and metals is associated with many adverse effects on human health, accompanied by oxidative stress. This study aimed to investigate the effects of co-exposure to PAHs and metals on oxidative stress in healthy adults. A preliminary longitudinal panel study was conducted between 2017 and 2018 in 45 healthy college students in Caofeidian, China. Six urinary monohydroxylated-PAHs (OH-PAHs), ten metals, 8-hydroxydeoxyguanosine (8-OHdG), and 8-iso-prostaglandin-F2α (8-iso-PGF2α) were measured. Linear mixed effects (LME) models and Bayesian kernel machine regression (BKMR) models were used to explore the associations of urinary OH-PAHs and metals with 8-OHdG and 8-iso-PGF2α. LME models showed that most urinary OH-PAHs and metals were positively associated with 8-OHdG and 8-iso-PGF2α. For example, a one-unit increase in the ln-transformed level of 1-hydroxypyrene (1-OHPyr) and vanadium (V) was associated with an increase of 143.8% (95% CI: 105.7 - 188.9%) and 105.8% (95% CI: 79.2-136.4%) in 8-OHdG; 8-iso-PGF2α increased by 118.9% (95% CI: 99.2-140.5%) and 83.9% (95% CI: 67.2-102.2%) with a one-unit increase in the ln-transformed level of 3-hydroxyphenanthrene (3-OHPhe) and aluminum (Al). BKMR models indicated the overall positive associations of the mixture of six OH-PAHs, ten metals, or six OH-PAHs and ten metals with 8-OHdG and 8-iso-PGF2α. Urinary 1-OHPyr and V were identified as the major contributors to the increased urinary 8-OHdG levels, while urinary 3-OHPhe and Al were the most vital contributors to the increased urinary 8-iso-PGF2α levels. The results revealed the longitudinal dose-response relationships of urinary OH-PAHs and metals with oxidative stress among healthy adults in Caofeidian; this finding serves as an evidence regarding the early health hazard caused by exposure to PAHs and metals and has implications for the environmental management of PAH and metal emissions in this area.

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