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1.
J Clin Nurs ; 33(3): 1048-1061, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37828751

RESUMO

AIMS: To establish a cognitive appraisal path model that examines the impact of stroke knowledge on stigma with the parallel mediating effects of negative and positive coping traits, as well as the moderating effects of family functioning. BACKGROUND: Stroke-related stigma, a 'mixture' of negative emotions involving internal criticism and external judgement, has been shown to impair patients' health outcomes. However, the specific factors underlying cognitive appraisals and their pathways remain unknown. DESIGN: A cross-sectional design. METHODS: The cross-sectional sample was from two stroke centres in China. Questionnaires were administered to collect sociodemographic data, stroke knowledge, coping traits, family functioning and stigma. Hierarchical regression models and the moderated parallel mediation model were constructed to analyse influencing pathways. The study adhered to the strengthening the reporting of observational studies in epidemiology guideline. RESULTS: All 144 samples reported stigma symptoms with a moderate-to-high standardising score. The best hierarchical regression model explains 55.5% of the variance in stigma. The parallel mediation model indicated that negative and positive coping traits co-mediating the association of stroke knowledge and stigma. After adding the family functioning as a moderator, the moderated parallel mediation model was confirmed with adequate fit indices. CONCLUSION: Among the cognitive appraisal factors affecting stroke-related stigma, stroke knowledge reduces stigma by modifying coping traits, while poor family functioning may serve as an opposing moderator. Notably, when family support is insufficient, enhanced stroke knowledge might paradoxically exacerbate the stigma. RELEVANCE TO CLINICAL PRACTICE: This study contributes knowledge on transforming health education and emphasises the pivotal roles of clinical nursing practitioners. In similar global contexts, the study highlights integrating health education, psychological counselling and family support to advance systematic nursing practices. PATIENT OR PUBLIC CONTRIBUTION: None.


Assuntos
Adaptação Psicológica , Capacidades de Enfrentamento , Humanos , Estudos Transversais , Pacientes , Cognição , Estigma Social
2.
J Environ Manage ; 366: 121860, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39025008

RESUMO

The biodegradation of guar gum by microorganisms sourced from coalbeds can result in low-temperature gel breaking, thereby reducing reservoir damage. However, limited attention has been given to the influence of salinity on the synergistic biodegradation of coal and guar gum. In this study, biodegradation experiments of guar gum and lignite were conducted under varying salinity conditions. The primary objective was to investigate the controlling effects and mechanisms of salinity on the synergistic biodegradation of lignite and guar gum. The findings revealed that salinity had an inhibitory effect on the biomethane production from the co-degradation of lignite and guar gum. The biomethane production declined with increasing salinity levels, decreasing from 120.9 mL to 47.3 mL. Even under 20 g/L salt stress conditions, bacteria in coalbeds could effectively break the gel and the viscosity decreased to levels below 5 mPa s. As salinity increased, the removal rate of soluble chemical oxygen demand (SCOD) decreased from 55.63% to 31.17%, and volatile fatty acids (VFAs) accumulated in the digestion system. High salt environment reduces the intensity of each fluorescence peak. Alterations in salinity led to changes in microbial community structure and diversity. Under salt stress, there was an increased relative abundance of Proteiniphilum and Methanobacterium, ensuring the continuity of anaerobic digestion. Hydrogentrophic methanogens exhibited higher salt tolerance compared to acetoclastic methanogens. These findings provide experimental evidence supporting the use of guar gum fracturing fluid in coalbeds with varying salinity levels.

3.
Opt Express ; 31(17): 28308-28319, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37710888

RESUMO

Quantum illumination is a quantum optical sensing technique, which employs an entangled source to detect low-reflectivity object immersed in a bright thermal background. Hybrid cavity-optomagnonics system promises to work as quantum illumination because a yttrium iron garnet (YIG) sphere can couple to microwave field and optical field. In this paper, we propose a scheme to enhance the entanglement between the output fields of the microwave and optical cavities by considering the intrinsic Kerr nonlinearity of the YIG. We investigate the difference between intrinsic Kerr nonlinearity and optomagnonical parametric-type coupling on improving entanglement. Our result show that the large value optomagnonical parametric-type coupling does not mean the large entanglement, nevertheless, the large value of Kerr nonlinearity does monotonously improve the entanglement for our group of parameters. Consequently, under feasible parameters of current experiment, the signal-to-noise ratio and probability of detection error can be improved after considering the magnon Kerr nonlinearity.

4.
J Org Chem ; 88(22): 15626-15638, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37885139

RESUMO

An efficient PhI(OAc)2-mediated regioselective hydrothiolation of allenamides with thiophenol via a radical process was developed to create a workable route to vinyl sulfides. The reaction exhibits a good functional group tolerance and high efficiency, affording the products in good to excellent yields. Mechanistic investigations indicated that the radical cascade proceeds through an allyl radical intermediate, which is formed via the addition of the PhS radical to the central carbon of allenamides. Moreover, the reaction was also efficient with selenophenol, providing the corresponding product, vinyl selenide, in a 99% yield.

5.
Org Biomol Chem ; 21(17): 3684-3690, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37070579

RESUMO

Cyclopropyl groups are widely found in pharmaceutical products and their application as precursors or key reaction intermediates benefits the development of a wide range of reactions. Herein, we report a facile protocol for the synthesis of this compound through gold-catalyzed [2 + 1] cycloaddition of allenamides with sulfoxonium ylides. The reaction exhibited good functional group tolerance and high efficiency, affording the products in good to excellent yields with good diastereoisomerism. The steric hindrance between the sulfonamide group and the gold catalyst determined the major configuration of the formed cis-cyclopropane product. Moreover, the aldehyde could be converted to amide under Schmidt reaction conditions and alcohol under reduction conditions.

6.
Mikrochim Acta ; 190(2): 56, 2023 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-36645516

RESUMO

Ultrabright green-emissive AIE nanoparticles (AIENPs) were used as signal-amplification probes to enhance the detectability of lateral flow immunoassay (LFIA). The detection performances of the green-emissive AIENP probes in both sandwich and competitive LFIA formats were systematically evaluated. Benefiting from its remarkable fluorescent brightness, the developed AIENP-LFIA showed versatile applicability for the detection of small molecules and macromolecules by using ochratoxin A (OTA) and procalcitonin (PCT) as model analytes, respectively. Under the optimum conditions, the detection limits (LODs) of the fabricated AIENP-LFIA for OTA and PCT were 0.043 ng mL-1 and 0.019 ng mL-1, respectively. These LOD values are significantly lower than those of conventional LFIA methods using gold nanoparticles as signal reporters. In addition, we demonstrated the practical application potential of AIENP-LFIA for the detection of OTA in real maize samples and PCT in real serum samples. These results indicated that the ultrabright green-emissive AIENPs were promising as signal output materials for building high-performance LFIA platform and broadening the application scenarios of LFIA.


Assuntos
Nanopartículas Metálicas , Ouro , Imunoensaio/métodos
7.
Sensors (Basel) ; 23(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37836865

RESUMO

Due to its advantages of low latency, low power consumption, and high flexibility, FPGA-based acceleration technology has been more and more widely studied and applied in the field of computer vision in recent years. An FPGA-based feature extraction and tracking accelerator for real-time visual odometry (VO) and visual simultaneous localization and mapping (V-SLAM) is proposed, which can realize the complete acceleration processing capability of the image front-end. For the first time, we implement a hardware solution that combines features from accelerated segment test (FAST) feature points with Gunnar Farneback (GF) dense optical flow to achieve better feature tracking performance and provide more flexible technical route selection. In order to solve the scale invariance and rotation invariance lacking problems of FAST features, an efficient pyramid module with a five-layer thumbnail structure was designed and implemented. The accelerator was implemented on a modern Xilinx Zynq FPGA. The evaluation results showed that the accelerator could achieve stable tracking of features of violently shaking images and were consistent with the results from MATLAB code running on PCs. Compared to PC CPUs, which require seconds of processing time, the processing latency was greatly reduced to the order of milliseconds, making GF dense optical flow an efficient and practical technical solution on the edge side.

8.
J Clin Nurs ; 32(13-14): 3909-3920, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36281076

RESUMO

AIMS AND OBJECTIVES: This study aimed to construct a structural equation model guided by the ecological model to explore the factors influencing health behaviour among hypertensive stroke patients 6 months post-stroke. BACKGROUND: Health behaviour is important for recurrence prevention in hypertensive stroke patients. Moreover, previous studies have indicated that health behaviour at the end of the recovery period is of particular concern. The ecological model provides an integrated perspective for explaining the factors influencing health behaviour. DESIGN: A cross-sectional study guided by the STROBE. METHODS: A total of 121 hypertensive stroke patients were included to assess stroke knowledge, health belief, depression, family function, chronic illness resource and health behaviour. A structural equation model was used to explore the health behaviour's factors and pathways. RESULTS: In the final ecological model, sex, education level, depression and chronic illness resource directly affected health behaviour. Stroke knowledge directly affected health behaviour and indirectly affected health behaviour through health belief and chronic illness resource. Family function indirectly affected health behaviour through health belief, depression and chronic illness resource. Health belief affected health behaviour indirectly through depression and chronic illness resource. CONCLUSIONS: Hypertensive stroke patients' health behaviour is jointly and interactively influenced by stroke knowledge, health belief, depression, family function and chronic illness resource. In particular, chronic illness resource is an important mediator of health behaviour. RELEVANCE TO CLINICAL PRACTICE: For clinical practitioners, health behaviour of men and patients with low educational levels should be specifically focused on. Additionally, it is necessary to provide stroke knowledge, establish health beliefs, control depression emotion and improve family function. Furthermore, chronic illness resources should be improved particularly due to its important mediating role. PATIENT OR PUBLIC CONTRIBUTION: Participants completed demographic and disease-related questionnaires during hospitalisation and completed other questionnaires when returning to hospital at 6 months follow-up.


Assuntos
Hipertensão , Acidente Vascular Cerebral , Masculino , Humanos , Estudos Transversais , Comportamentos Relacionados com a Saúde , Hipertensão/complicações , Modelos Teóricos , Acidente Vascular Cerebral/complicações , Inquéritos e Questionários , Doença Crônica
9.
BMC Genomics ; 23(1): 15, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34983398

RESUMO

BACKGROUND: Neonicotinoids are widely applied in the control of the destructive agricultural pest Bemisia tabaci, and resistance against these chemicals has become a common, severe problem in the control of whiteflies. To investigate the molecular mechanism underlying resistance against nenonicotinoids in whiteflies, RNA-seq technology was applied, and the variation in the transcriptomic profiles of susceptible whiteflies and whiteflies selected by imidacloprid, acetamiprid and thiamethoxam treatment was characterized. RESULTS: A total of 90.86 GB of clean sequence data were obtained from the 4 transcriptomes. Among the 16,069 assembled genes, 584, 110 and 147 genes were upregulated in the imidacloprid-selected strain (IMI), acetamiprid-selected strain (ACE), and thiamethoxam (THI)-selected strain, respectively, relative to the susceptible strain. Detoxification-related genes including P450s, cuticle protein genes, GSTs, UGTs and molecular chaperone HSP70s were overexpressed in the selected resistant strains, especially in the IMI strain. Five genes were downregulated in all three selected resistant strains, including 2 UDP-glucuronosyltransferase 2B18-like genes (LOC 109030370 and LOC 109032577). CONCLUSIONS: Ten generations of selection with the three neonicotinoids induced different resistance levels and gene expression profiles, mainly involving cuticle protein and P450 genes, in the three selected resistant whitefly strains. The results provide a reference for research on resistance and cross-resistance against neonicotinoids in B. tabaci.


Assuntos
Hemípteros , Inseticidas , Animais , Hemípteros/genética , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Neonicotinoides , Nitrocompostos , Tiametoxam
10.
Small ; 18(29): e2202623, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35754173

RESUMO

Despite the excellent optoelectronic properties, organic-inorganic hybrid perovskite solar cells (PSCs) still present significant challenges in terms of ambient stability. CsPbI2 Br, a member of all-inorganic perovskites, may respond to this challenge because of its inherent high stability against light, moisture, and heat, and therefore has gained tremendous attraction recently. However, the practical application of CsPbI2 Br is still impeded by the notorious phenomenon of photoinduced halide segregation. Herein, by applying first-principles calculations, the stability, electronic structure, defect properties, and ion-diffusion properties of the stoichiometric CsPbI2 Br (110) surface and that with the adsorption of KX (X = Cl, Br, I) are systematically investigated. It is found that the adsorbed KX can serve as an external substitute of the halogen vacancies on the surface, therefore inhibiting halogen segregation and improving the stability of the CsPbI2 Br surface. The KX can also eliminate deep-level defect states caused by antisites, thereby contributing to the promoted optoelectronic properties of CsPbI2 Br. The mechanistic understanding of surface passivation in this work can lay the foundation for the future design of CsPbI2 Br PSCs with optimized optoelectronic performance.

11.
Opt Express ; 30(23): 42347-42361, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36366690

RESUMO

In this paper, we employ the atomic arrays in one-dimensional optical waveguides to simulate topological phases, where the waveguide is modeled as a one-dimensional infinitely long coupled cavity array. Under the Markov approximation, the coherent and dissipative coupling between atoms is established by eliminating waveguide modes. When the detuning between atoms and cavity fields lies in the band gap, the dynamics of the system is completely dominated by the coherent interaction. Under this condition, we designed three atomic arrays with different geometries and show that the topologically trivial and non-trivial phases of atomic arrays can be simulated. Furthermore, by introducing periodic atomic driving, the topological phase transition can be induced by adjusting the driving parameters. Finally, we investigate the effect of next-nearest neighbor interactions on topological state transfer and find that the next-nearest neighbor interactions break the degenerated bandgap state and establish a topological state transfer channel.

12.
Immunol Invest ; 51(2): 316-330, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33161796

RESUMO

BACKGROUND: Systemic lupus erythematosus (SLE) is an autoimmune disease. Tumor necrosis factor ligand superfamily member 4 (TNFSF4) is an inflammatory factor that has been discussed in different inflammatory diseases and cancers. However, relationship between TNFSF4 and SLE is limited. MATERIAL AND METHODS: The present case-control study recruited 400 SLE patients and 600 healthy controls from Southern Chinese Han origin. Plasma levels of TNFSF4 were tested by enzyme linked-immunosorbent assay, and association of rs2205960, rs704840, rs844648, rs3850641 and rs17568 polymorphisms in TNFSF4 gene with SLE risk was evaluated by TaqMan assay according to genotyping. RESULTS: Plasma levels of TNFSF4 were significantly higher in SLE patients than that in healthy controls (390.87 (189.10-906.01) versus 132. 70 (81.27-195.58) pg/ml, P < 0.001). Increased levels of TNFSF4 were positively related to SLE disease activity score, optic nerve injury, leukopenia, and hypocompleminemia. Genotype TT+TG, allele T of rs2205960, genotype GG+GT of rs704840, genotype AA of rs844648 and rs17568 were significantly related to SLE risk (all P < 0.05). Moreover, polymorphism rs844648 was related to SLE patients with clinical feature rash either for genotype AA or allele A. CONCLUSION: TNFSF4 was elevated in SLE patients and may associate with SLE susceptibility in Southern Chinese Han population.


Assuntos
Lúpus Eritematoso Sistêmico , Ligante OX40 , Alelos , Estudos de Casos e Controles , China/epidemiologia , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Lúpus Eritematoso Sistêmico/genética , Ligante OX40/genética , Polimorfismo de Nucleotídeo Único
13.
J Integr Neurosci ; 21(1): 35, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35164471

RESUMO

Owing to the small number of patients with tyrosine hydroxylase (TH) deficiency, no genotype-phenotype correlations have yet been identified. To investigate the genotype-phenotype correlation of R233H mutation in TH deficiency, we analyzed the clinical manifestations and treatment responses of four patients with the R233H homozygous mutation. Thirty-eight additional patients, available from the literature, known to be homozygous or heterozygous for the R233H mutation, were combined with the four cases from our hospital. Data for a total of 42 patients were retrieved. Our four patients showed clinical presentation consistent with Type A TH deficiency, and responded well to levodopa therapy, with an improvement in clinical symptoms within 1-2 weeks. In the 42 patients, 20 of 42 patients (48%) were homozygous and 22 (52%) were heterozygous for the R233H mutation. Of the 20 patients who were homozygous for the R233H mutation, a majority (80%) suffered from Type A TH deficiency. Of the 8 patients that were heterozygous for the R233H/the mutation located downstream of exon 11, 7 patients (86%) suffered from Type B TH deficiency. Of the 7 patients who were heterozygous for the R233H/nonsense mutation, 6 (86%) suffered from Type B TH deficiency. Genotype-phenotype correlation of R233H mutation was observed in TH deficiency. The homozygous R233H mutation frequently manifests as Type A TH deficiency, whereas R233H/nonsense mutation or any mutation located downstream of exon 11 manifests as Type B TH deficiency.


Assuntos
Distúrbios Distônicos/congênito , Criança , Pré-Escolar , Distúrbios Distônicos/genética , Distúrbios Distônicos/fisiopatologia , Feminino , Estudos de Associação Genética , Humanos , Lactente , Masculino , Fenótipo
14.
Biochem Biophys Res Commun ; 568: 174-179, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34246051

RESUMO

The aim of the study was to develop a model of coronary microembolization (CME) in rats at a lower cost. We developed a novel rat model without thoracotomy and ventilation under the guidance of echocardiography. Rats were sacrificed at 3 h, 24 h and 1 month postoperatively in both the Echo-CME and Open-chest CME groups for the comparison of the modeling accuracy, mortality, cardiopulmonary circulation, pleural adhesion and ventilation-induced lung injury (VILI). Results showed that the coronary microthrombus formed at 3 h and reached its peak at 24 h postoperatively, which included platelet aggregation and fibrin web. The Echo-group increases success rates, decreased mortality, postoperative complications including pleural adhesion, cardiopulmonary dysfunction and VILI postoperatively than the Open-chest group at 1month postoperatively. The ejection fraction of the CME group decreased to 50% and obvious cardiac fibrosis formed at 3 months postoperatively. Our unique surgical method provided a platform to study molecular mechanisms and potential new pathways for CME treatment.


Assuntos
Vasos Coronários/patologia , Ecocardiografia , Embolia/patologia , Trombose/patologia , Animais , Vasos Coronários/diagnóstico por imagem , Modelos Animais de Doenças , Embolia/diagnóstico por imagem , Masculino , Ratos Sprague-Dawley , Trombose/diagnóstico por imagem
15.
Opt Lett ; 46(13): 3075-3078, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34197384

RESUMO

A weak force sensor scheme is presented in an optomechanical system, in which the two cavity modes couple to a mechanical mode with linear and quadratic coupling. Due to introducing time-dependent hopping, the linear and quadratic coupling terms coexist under the rotating-wave approximation in the interaction picture. Compared with the quantum non-demolition measurement (ignoring the quadratic optomechanical coupling), the current scheme can decrease the additional noise to a lower level. Our proposal provides a promising platform for improving the detection of a weak force.

16.
Aging Clin Exp Res ; 33(11): 2967-2977, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33837500

RESUMO

OBJECTIVE: Despite the high incidence and mortality of cardiovascular events in hyperuricemia patients, the role of serum uric acid in cardiovascular diseases is still controversial. The aim of this meta-analysis was to explore the difference of carotid intima-media thickness in hyperuricemia and control groups. METHODS: We performed this meta-analysis by searching the PubMed, Cochrane Library, Embase and Web of Science databases up to July 2020. The 95% confidence intervals and standard mean differences were calculated to analyze the differences in carotid intima-media thickness in hyperuricemia groups and control groups. Sensitivity analysis, subgroup analysis and meta-regression were used to explore the sources of heterogeneity. Publication bias was evaluated by funnel plot and Begg's regression test. We used Stata 14.0 software to complete our analyses. RESULTS: A total of 8 articles were included. The results showed that there was a significant increase in carotid intima-media thickness in the hyperuricemia groups compared with the control groups [SMD = 0.264, 95% CI (0.161-0.366), P < 0.001]. Subgroup analyses showed that age, sample size, blood pressure and body mass index were not the source of heterogeneity. Meta-regression enrolled the method of CIMT measurement, location, age, smoking and diabetes mellitus as categorical variables, but none of these factors was found to be significant in the model. The Begg's test value (P = 0.174) was greater than 0.05, indicating there was no publication bias. CONCLUSION: The results showed that carotid intima-media thickness was increased in hyperuricemia patients compared with controls, which indicated that hyperuricemia patients may have a higher risk of cardiovascular diseases.


Assuntos
Doenças Cardiovasculares , Hiperuricemia , Pressão Sanguínea , Espessura Intima-Media Carotídea , Humanos , Hiperuricemia/complicações , Ácido Úrico
17.
Aging Clin Exp Res ; 33(9): 2393-2403, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33783714

RESUMO

OBJECTIVE: To provide evidence on the effects of vitamin D supplementation on knee osteoarthritis (KOA) and new targets for clinical prevention and treatment of KOA. METHOD: The PubMed, Embase, Web of science, Wanfang, CNKI and SinoMed databases were retrieved to investigate the effects of vitamin D supplementation on patients with KOA. The search time was from databases establishment to 15 November 2020. RevMan5.3 software was used for meta-analysis. The results were expressed as standardized mean difference (SMD) with 95% confidence interval (CI) or weighted mean difference (WMD) with 95% confidence interval (CI). RESULTS: A total of 1599 patients with osteoarthritis of the knee were included in the study, which involved six articles. The results of the meta-analysis showed that vitamin D supplementation is statistically significant for WOMAC score (SMD = - 0.67, 95% CI - 1.23 to - 0.12) in patients with KOA, including WOMAC pain score (SMD = - 0.32, 95% CI - 0.63 to - 0.02), function score (SMD = - 0.34, 95% CI - 0.60 to - 0.08) and stiffness score (SMD = - 0.13, 95% CI - 0.26 to - 0.01). In subgroup analysis, vitamin D supplementation less than 2000 IU was statistically significant for the reduction of stiffness score (SMD = - 0.22, 95% CI - 0.40 to - 0.04). Vitamin D supplements can reduce synovial fluid volume progression in patients with KOA (SMD = - 0.20, 95% CI - 0.39 to - 0.02). There was no statistical significance in improving tibia cartilage volume (SMD = 0.12, 95% CI - 0.05 to 0.29), joint space width (SMD = - 0.10, 95% CI - 0.26 to 0.05) and bone marrow lesions (SMD = 0.03, 95% CI - 0.26 to 0.31). CONCLUSION: Vitamin D supplements can improve WOMAC pain and function in patients with KOA. But there is a lack of strong evidence that vitamin D supplementation can prevent structural progression in patients with KOA.


Assuntos
Osteoartrite do Joelho , Humanos , Articulação do Joelho , Osteoartrite do Joelho/tratamento farmacológico , Dor , Vitamina D/uso terapêutico , Vitaminas
18.
J Cell Biochem ; 121(2): 1790-1800, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31642099

RESUMO

To search the modulation mechanism of loureirin B, a flavonoid is extracted from Dracaena cochinchinensis, on tetrodotoxin-resistant (TTX-R) sodium channel in dorsal root ganglion (DRG) neurons of rats. Experiments were carried out based on patch-clamp technique and molecular biological methods. We observed the time-dependent inhibition of loureirin B on TTX-R sodium currents in DRG neurons and found that neither occupancy theory nor rate theory could well explain the time-dependent inhibitory effect of loureirin B on TTX-R sodium currents. It suggested that a second messenger-mediated signaling pathway may be involved in the modulation mechanism. So the cyclin AMP (cAMP) level of the DRG neurons before and after incubation with loureirin B was tested by ELISA Kit. Results showed that loureirin B could increase the cAMP level and the increased cAMP was caused by the enhancement of adenylate cyclase (AC) induced by loureirin B. Immunolabelling experiments further confirmed that loureirin B can promote the production of PKA in DRG neurons. In the presence of the PKA inhibitor H-89, the inhibitory effect of loureirin B on TTX-R sodium currents was reversed. Forskolin, a tool in biochemistry to raise the levels of cAMP, also could reduce TTX-R sodium currents similar to that of loureirin B. These studies demonstrated that loureirin B can modulate the TTX-R sodium channel in DRG neurons via an AC/cAMP/PKA pathway involving the activation of AC and PKA, which also can be used to explain the other pharmacological effects of loureirin B.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Resistência a Medicamentos , Gânglios Espinais/fisiologia , Neurônios/fisiologia , Resinas Vegetais/farmacologia , Canais de Sódio/química , Tetrodotoxina/farmacologia , Potenciais de Ação , Animais , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Potenciais da Membrana , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley , Bloqueadores dos Canais de Sódio/farmacologia
19.
Pestic Biochem Physiol ; 163: 209-215, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31973859

RESUMO

Neonicotinoids are commonly used for the control of the whitefly Bemisia tabaci in cotton field. Laboratory test and field experiments have found that whitefly has a high risk of developing resistance and cross-resistance to the pesticide. Over expression of cytochrome P450 is one of the main mechanism that controls pesticide resistance in many insects. In this study we use MEAM1 whitefly, the dominant cryptic species of B. tabaci in Xinjiang cotton field, to investigate the possible resistance and cross-resistance mechanism controlled by cytochrome P450 enzymes. The P450 enzyme activity was higher in both selected strains of imidacloprid and acetamipird than that of susceptible strain. Synergism test showed that piperonyl butoxide (PBO) distinctly increased the control efficiency of imidacloprid and acetamiprid to the two resistance selected strains. Four out of 13 cytochrome genes, CYP4CS3, CYP6CX5, CYP6DW2 and CYP6CM1 were significantly up-regulated in the two selected strains based on real-time fluorescence quantitative PCR results. Other 3 genes, CYP6CX2, CYP6CX4 and CYP6DW3 were only highly expressed in the acetamiprid selected strain instead of the susceptible strain and imidacloprid selected strain. CYP6CM1 showed the highest expression level among all the 13 tested genes. No functional mutation of CYP6CM1 was found by sequence analysis. The possible role of these genes involving the resistance and cross-resistance of the whitefly MEAM1 cryptic species against neonicotinoids was discussed.


Assuntos
Hemípteros , Inseticidas , Animais , China , Sistema Enzimático do Citocromo P-450 , Resistência a Inseticidas , Neonicotinoides , Nitrocompostos
20.
Water Sci Technol ; 82(1): 170-184, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32910801

RESUMO

In this study, manganese dioxide was evenly distributed on the surface of activated carbon (AC), and the porous structure of AC and the surface functional groups of manganese dioxide were used to adsorb the heavy metal ion Pb(II). The advantages of microwave heating are fast heating and high selectivity. The mole ratio control of the AC and MnO2 in 1:0.1, microwave heating to 800 °C, heat preservation for 30 min. The maximum adsorption capacity of the MnO2-AC prepared by this method on Pb(II) can reach 664 mg/L at pH = 6. It can be observed by scanning electron microscope (SEM) that manganese dioxide particles are dispersed evenly on the surface and pore diameter of AC, and there is almost no agglomeration. The specific surface area was 752.8 m2/g, and the micropore area was 483.9 m2/g. The adsorption mechanism was explored through adsorption isotherm, adsorption kinetics, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS). It is speculated that the adsorption mechanism includes electrostatic interaction and specific adsorption, indicating that lead ions enter into the void of manganese dioxide and form spherical complexes. The results showed that the adsorption behavior of Pb(II) by MnO2-AC was consistent with the Langmuir adsorption model, the quasi-second-order kinetic model, and the particle internal diffusion model.


Assuntos
Compostos de Manganês , Poluentes Químicos da Água/análise , Adsorção , Carvão Vegetal , Íons , Chumbo , Micro-Ondas , Óxidos
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