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1.
Physiol Plant ; 176(3): e14378, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887925

RESUMO

D-2-hydroxyglutarate dehydrogenase (D2HGDH) is a mitochondrial enzyme containing flavin adenine dinucleotide FAD, existing as a dimer, and it facilitates the specific oxidation of D-2HG to 2-oxoglutarate (2-OG), which is a key intermediate in the tricarboxylic acid (TCA) cycle. A Genome-wide expression analysis (GWEA) has indicated an association between GhD2HGDH and flowering time. To further explore the role of GhD2HGDH, we performed a comprehensive investigation encompassing phenotyping, physiology, metabolomics, and transcriptomics in Arabidopsis thaliana plants overexpressing GhD2HGDH. Transcriptomic and qRT-PCR data exhibited heightened expression of GhD2HGDH in upland cotton flowers. Additionally, early-maturing cotton exhibited higher expression of GhD2HGDH across all tissues than delayed-maturing cotton. Subcellular localization confirmed its presence in the mitochondria. Overexpression of GhD2HGDH in Arabidopsis resulted in early flowering. Using virus-induced gene silencing (VIGS), we investigated the impact of GhD2HGDH on flowering in both early- and delayed-maturing cotton plants. Manipulation of GhD2HGDH expression levels led to changes in photosynthetic pigment and gas exchange attributes. GhD2HGDH responded to gibberellin (GA3) hormone treatment, influencing the expression of GA biosynthesis genes and repressing DELLA genes. Protein interaction studies, including yeast two-hybrid, luciferase complementation (LUC), and GST pull-down assays, confirmed the interaction between GhD2HGDH and GhSOX (Sulfite oxidase). The metabolomics analysis demonstrated GhD2HGDH's modulation of the TCA cycle through alterations in various metabolite levels. Transcriptome data revealed that GhD2HGDH overexpression triggers early flowering by modulating the GA3 and photoperiodic pathways of the flowering core factor genes. Taken together, GhD2HGDH positively regulates the network of genes associated with early flowering pathways.


Assuntos
Arabidopsis , Flores , Regulação da Expressão Gênica de Plantas , Giberelinas , Gossypium , Fotoperíodo , Proteínas de Plantas , Gossypium/genética , Gossypium/fisiologia , Gossypium/metabolismo , Flores/genética , Flores/fisiologia , Arabidopsis/genética , Arabidopsis/fisiologia , Arabidopsis/metabolismo , Giberelinas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/genética , Plantas Geneticamente Modificadas , Transporte de Elétrons
2.
Chinese Journal of Neurology ; (12): 333-340, 2024.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1029208

RESUMO

Objective:To investigate and analyze the use and duration of anti-seizure medications (ASMs) in patients with chronic epilepsy after autoimmune encephalitis (AE), as well as the effect of ASMs use on the formation of this epilepsy to provide relevant evidence for the choice of ASMs in patients with acute seizure or chronic epilepsy after AE.Methods:A retrospective follow-up study was performed on AE patients (including patients with antibody-negative autoimmune limbic encephalitis) diagnosed in the Affiliated Brain Hospital of Nanjing Medical University from December 1, 2013 to October 31, 2022. The dates of the first seizure onset and the chronic epilepsy formation (defined as 1 year after immunotherapy) were recorded. The initial time, types and numbers of ASMs used in acute symptomatic seizure (ASS) and the maintenance time, types and numbers of ASMs in chronic epilepsy period (the continuation or the combined therapy of ASMs) were collected, respectively. A Logistic regression model was used to analyze multi-influencing factors on the formation of chronic epilepsy after AE.Results:A total of 332 patients were enrolled in this study, of whom 32.5% (108/332) with antibody-negative autoimmune limbic encephalitis. In total, 54.8% (182/332) of patients were males, and the age of onset was (40.7±19.7) years. Finally, 81.0% (269/332) of participants manifested ASS, and 57.2% (190/332) developed chronic epilepsy up to the last follow-up. The follow-up time was 1-8 years, with a median of 2 years. All patients received ASMs treatment during ASS period. Among the ASS patients, 48.0% (129/269) were prescribed monotherapy of ASMs, and 52.0% (140/269) were given the combined therapy of ASMs. Of all the patients with ASMs, 70.3% (189/269) were given early ASMs treatment (within 24 hours of the seizure onset), and 29.7% (80/269) were given delayed ASMs treatment. Subsequently, 81.0% (218/269) of the ASS patients continued the ASMs treatment (>6 months), and 19.0% (51/269) stopped use of ASMs. In the chronic epilepsy stage, 79.5% (151/190) of thee epilepsy patients continued ASMs, of whom 37.1% (56/151) were treated with monotherapy, and 62.9% (95/151) were treated with combined therapy. The incidence of chronic epilepsy was 81.3% (65/80) in the delayed ASMs treatment group, higher than the 66.1% (125/189) in the early ASMs treatment group,with statistically significant difference (χ 2=6.189, P=0.013). There were no statistically significant differences in the ASMs types and whether combined therapy of ASMs was used between chronic epilepsy group and non-chronic epilepsy group. The Logistic regression model showed that delayed ASMs treatment ( OR=2.306,95% CI 1.032-6.387, P=0.018), positive anti-neuronal intracellular antibodies ( OR=2.626,95% CI 1.536-9.531, P=0.004,compared with anti- neuronal surface antibodies), abnormal brain magnetic resonance imaging ( OR=9.883,95% CI 3.608-27.071, P<0.001), elevated cerebrospinal fluid protein ( OR=2.874,95% CI 1.115-7.409, P=0.029), and abnormal electroencephalogram ( OR=9.287,95% CI 3.767-22.896, P<0.001) were independent risk factors for chronic epilepsy after AE. Conclusions:The development of chronic epilepsy after AE is associated with the occurrence of ASS and the delayed use of ASMs, but the type of ASMs or whether the combined ASMs therapy is used is not associated with the formation of chronic epilepsy after AE. It is concluded that early ASMs treatment for the AE patients with ASS may reduce the incidence of chronic epilepsy. For AE patients with ASS who have undergone early standardized treatment, long-term, combined ASMs treatment may not be necessary.

3.
Environ Sci Pollut Res Int ; 30(32): 78521-78536, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37271788

RESUMO

The effect of polydopamine (PDA) modification on aminated Fe3O4 nanoparticles (Fe3O4-NH2)/graphite oxide (GO)/ß-cyclodextrin polymer cross-linked by citric acid (CDP-CA) composites were studied for the removal of a cationic dye (methylene blue, MB) and an anionic dye (Congo red, CR) from waters. The micro-structural and magnetic characterizations confirmed the successful preparation of Fe3O4-NH2/GO/CDP-CA and PDA/Fe3O4-NH2/GO/CDP-CA composites. The maximum MB and CR adsorption capacities of Fe3O4-NH2/GO/CDP-CA were 75 mg/g and 104 mg/g, respectively, while the corresponding amounts for PDA/Fe3O4-NH2/GO/CDP-CA composite were 195 mg/g and 64 mg/g, respectively. The dye sorption behaviors of these two composites were explained by their corresponding surface-charged properties according to the measured zeta potential results. Moreover, the high saturation magnetizations and the stable dye removal rate in the adsorption-desorption cycles indicated the good recyclability and reusability of the fabricated composites.


Assuntos
Ciclodextrinas , Grafite , Grafite/química , Ácido Cítrico , Óxidos/química , Adsorção , Fenômenos Magnéticos
4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1024936

RESUMO

Epilepsy surgery is an effective treatment of drug-resistant epilepsy.Once patients became seizure free for certain period after epilepsy surgery,whether anti-seizure medications(ASMs)could be withdrawn is the primary concern of clinicians and patients.However,there is no consensus about management of anti-seizure medications in patients after epilepsy surgery.Patients after epilepsy surgery can withdraw ASMs when they become seizure free for 1 to 2 years.The dose reduction is usually done at every 2 to 3 months.For patients receiving multiple ASMs,each one should be individually tapered completely prior to the subsequent medication and the primary medication is always withdrawn in the end.Longer epilepsy duration prior to surgery,older age at surgery,patients with focal cortical dysplasia,incomplete resection of the epileptogenic zone and presence of interictal epileptiform discharges in postoperative EEG may predict the risk of seizure relapse in patients who underwent ASM withdrawal after epilepsy surgery.Patients with seizure relapse on ASM withdrawal generally have benign outcome after reinstitution of medical treatment.

5.
Zhongguo Zhong Yao Za Zhi ; 47(20): 5544-5549, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36471971

RESUMO

Repeated silica gel column chromatography, reversed-phase C_(18) column chromatography, Sephadex LH-20 column chromatography, high performance liquid chromatography and semi-preparative medium pressure liquid chromatography were performed to separate and purify the chemical constituents of Hypericum lagarocladum. Spectroscopic methods such as mass spectrometry(MS) and nuclear magnetic resonance(NMR) combined with physicochemical properties were adopted in identifying the structure of the isolated compounds. Ten compounds were isolated from the ethyl acetate fraction of H. lagarocladum and identified as lagarxanthone A(1), 1,7-dihydroxyxanthone(2), 3,4,5-trihydroxyxanthone(3), 2,7-dihydroxy-1-methoxyxanthone(4), 1,3-dihydroxy-7-methoxyxanthone(5), 1,5-dihydroxy-8-methoxyxanthone(6), 3,4-dihydroxy-2-methoxyxanthone(7), 3,4-dihydroxy-5-methoxyxanthone(8), 2,3-dimethoxyxanthone(9), and 2,3,4-trimethoxyxanthone(10). Among them, compound 1 was a new compound, and compounds 2-10 were isolated from this plant for the first time. These ten compounds were tested for glucose uptake in L6 cells, and the results showed that all the compounds had no significant effect on glucose uptake.


Assuntos
Hypericum , Xantonas , Hypericum/química , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Glucose
6.
Chinese Journal of Neurology ; (12): 65-70, 2022.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-933758

RESUMO

The postictal state refers to the abnormal condition occurring between the end of an epileptic seizure and return to baseline condition,including a variety of cognitive, motor, sensory, autonomic, mental and behavioral impairments. The symptoms which may last from seconds to days are various and the severity is different. It also may exert great impact on patients′ health and quality of life. However, the lack of relevant studies at home and abroad, along with the absence of correct understanding of this in clinical practice, may lead to frequent misdiagnosis and mistreatment. This article will review the concepts, pathophysiological mechanisms, clinical manifestations, diagnosis, differential diagnosis, clinical significance and intervention strategies, aiming at deepening the understanding of the phenomenon, as well as providing references for further clinical research.

7.
Acta Pharmaceutica Sinica ; (12): 2767-2773, 2022.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-941494

RESUMO

Silica gel column chromatography, reversed phase C18 column chromatography, Sephadex LH-20 gel column chromatography, high performance liquid chromatography and medium performance semi preparative liquid chromatography were performed to separate and purify the chemical constituents of Hypericum lagarocladum N. Robson. Spectroscopic methods such as MS and NMR combined with physicochemical properties were applied in identifying the structures of the isolated compounds. A total of 11 compounds were isolated and identified as hyperlagarone A (1), hyperpatulone E (2), hyperbeanol G (3), uralione D (4), tomoeone F (5), pyramidatone A (6), tomoeone A (7), tomoeone B (8), hyperbeanol C (9), hyperbeanol A (10), and hypercohone G (11), respectively. Compound 1 is a new polycyclic polyprenylated acylphloroglucinol derivative, and compounds 2-11 are isolated from this plant for the first time. 11 compounds were tested for glucose uptake in L6 cells, and the results showed that compounds 7 and 8 had significant effect on glucose uptake.

8.
Acta Pharmaceutica Sinica ; (12): 3268-3276, 2021.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-906841

RESUMO

Cryptotanshinone (CPT), an active ingredient with the inhibitory effect on brain glioma cells, is trapped with poor solubility and low tumor permeability. Therefore, it is urgent to design nano drug delivery systems characterized with deep penetration and accurate targeting. In the present study, tLyp-1 modified liposomes loaded with CPT (tLipo/CPT) was prepared by emulsion solvent evaporation method. Peptide tLyp-1 which targeting tumor angiogenesis and neuropilin receptors (NRP) was modified on surface of CPT liposomes, with the aim of active targeting brain glioma cells and further release CPT precisely. The size and polymer dispersity index (PDI) of tLipo/CPT were (162.2 ± 14.6) nm and 0.24 ± 0.03. The optimal molar ratio of tLyp-1 modified on CPT liposomes was 0.5% determined by intracellular fluorescence parameters. The morphology displayed a smooth sphericity structure as determined by transmission electron microscope. Efficiency of CPT encapsulated in tLipo/CPT was detected by high performance liquid chromatography. The encapsulation efficiency of CPT was (70.06 ± 7.22) %. Liposomes modified with tLyp-1 peptide (tLipo) were internalized more than liposomes not modified with tLyp-1 (Lipo) by GL261 cells. Fluorescence intensity of tLipo in GL261 cells increased 40% than that of Lipo. Furthermore, we proved that the intake of tLipo/CPT in GL261 cells was mediated by NRP-1 receptor. MTT analysis indicated that tLipo/CPT significantly inhibit the proliferation of GL261 cells. The half maximal inhibitory concentration (IC50) was 5.70 μmol·L-1. In vitro blood-brain barrier (BBB) model experiment indicated that tLipo/CPT could penetration across BBB. Moreover, in vivo fluorescence biodistribution study indicated tail vein injection of DiR labeled tLipo after 0.5 h, DiR fluorescence could be observed in the brain of mice. Even after 24 h, DiR fluorescence still was observed in the brain. Our research certified that tLipo/CPT can penetrate the BBB and show effect of anti-glioma by inhibiting the proliferation of GL261 cells. The animal experiment was carried out in accordance with protocol evaluated and approved by the Ethics Committee of Nanjing University of Chinese Medicine.

9.
Chinese Journal of Neurology ; (12): 211-218, 2021.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-885405

RESUMO

Objective:To explore the seizure recurrence and prognosis of epilepsy in relapse after anti-epileptic drugs (AEDs) withdrawal, and the influencing factors for these conditions.Methods:From December 2009 to August 2018, patients from the Affiliated Brain Hospital of Nanjing Medical University who relapsed after AEDs withdrawal were collected and followed up for at least 18 months. The seizure recurrence and prognosis of these patients were prospectively observed. The Kaplan-Meier method was used for survival analysis. The associated risk factors of the second relapse in the enrolled patients were analyzed by multivariate Cox analysis. The included patients were divided into good prognosis group and poor prognosis group according to whether they had achieved seizure freedom for at least one year after the first relapse. A multivariate Cox regression model was used to analyze the independent risk factors affecting their prognosis.Results:A total of 56 patients with epilepsy in relapse after AEDS withdrawal were collected. The average follow-up period was 46.23 months (18-120 months) from the initial time of seizure recurrence, and 21 patients (37.5%) had the second seizure recurrence. The relapsing risk in patients who continued to be observed without adding AEDs was higher than those who were treated immediately with drugs [9/16 vs 30.0% (12/40)], but without statistically significant difference (χ2=2.220, P=0.071). The results of univariate analysis showed that focal seizures, seizure frequency more than once per month before remission and poly-drug therapy before AEDs withdrawal were associated with high risk of the second relapse. Poly-drug therapy was an independent risk factor for the second relapse by multivariate Cox analysis ( HR=3.383, 95% CI 1.257-9.105). Of the 56 patients with epilepsy in relapse after AEDs withdrawal, 47 patients (83.9%) had a good prognosis without seizure for at least one year, and of 33 patients who were followed up for three years or more, 26 (78.8%) had no seizure for at least two years. Between the group retreated immediately after the first recurrence and the group without immediate treatment [87.5% (35/40) vs 12/16],there were no statistically significant differences on the proportions of good prognosis (χ2=2.333, P=0.258). Univariate analysis showed that the course of epilepsy>6 months before initial treatment, the frequency of seizures>1/month before remission, symptomatic epilepsy and poly-drug therapy were associated with the poor prognosis. However, none of independent risk factors was found for the poor prognosis through the multivariate analysis. Conclusions:The prognosis of patients with epilepsy in relapse after AEDs withdrawal is well, and about 2/3 patients with epilepsy in relapse after AEDs withdrawal have no more seizure recurrences. The poly-drug therapy before AEDs withdrawal may be an independent risk factor for the second seizure relapse.

10.
Acta Pharmaceutica Sinica ; (12): 2112-2118, 2021.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-887061

RESUMO

Ma-Xing-Shi-Gan Decoction is a classic prescription. However, the interaction among multiple components of the decoction and the change of phase state are not clear. Moreover, the relationship between the physical phase state aggregated by multiple components and the efficacy still needs to be studied. In this study, we monitored the particle size changes of Ma-Xing-Shi-Gan Decoction in real time. Then we isolated different phase states by centrifugation, analyzed their composition distribution and tested their antibacterial activity. We added chemical interference agents to investigate the interaction of multi-component physical phase states accompanied by the observation of particle size change and morphology. We also studied the correlation between antibacterial activity and physical structure of phase states. The results showed during boiling process the degree of hybridization of particles was decreased and the particle size distribution was narrowed and stabilized at 170 nm. The distribution of organic and inorganic components was heterogeneous among different phase states. S-13500, supernatant isolated by 13 500 ×g centrifugation, constituted by ephedrine, amygdalin, glycyrrhizic acid and inorganic components Ca, K, Mg, etc., had the strongest antibacterial activity. The molecular interaction force in the active physical phase state was mainly hydrophobic and hydrogen bond. The destruction of the interaction force will lead to the change of phase structure and the decrease of antibacterial activity in vitro and in vivo. This study confirms that, in the boiling process of the Ma-Xing-Shi-Gan Decoction, the chemical components interweave and interact to form new physical phase states, leading to heterogeneous distribution of components. The antimicrobial activity of the active phase depends on both chemical composition and physical structure, which provides a direct evidence for the physical basis of the efficacy of traditional Chinese medicine.

11.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-878919

RESUMO

To establish the HPLC fingerprint and multi-component determination method of fried Glycyrrhizae Radix et Rhizoma pieces. HPLC analysis was performed on Thermo Acclaim ~(TM)120 C_(18) column(4.6 mm×250 mm, 5 μm). Acetonitrile-0.1% phosphoric acid aqueous solution was taken as the mobile phase for gradient elution. The flow rate was 1 mL·min~(-1),the column temperature was maintained at 30 ℃, and the detection wavelength was 237 nm and 360 nm. The similarity of 15 batches of fried Glycyrrhizae Radix et Rhizoma pieces was higher than 0.849, and 17 common peaks were identified. Liquiritin, isoliquiritin apioside, isoliquiritin, liquiritigenin, isoliquiritigenin and glycyrrhizic acid were identified; among them, the mass fractions of Liquiritin, isoliquiritin apioside, isoliquiritin, liquiritigenin, glycyrrhizic acid were were 0.519%-3.058%, 0.227%-0.389%, 0.070%-0.439%, 0.038%-0.173%, 1.381%-4.252%, respectively. According to the cluster analysis, the 15 batches of decoction pieces were classified into three categories; principal component analysis screened out four principal components, with the cumulative variance contribution rate of 86.630%, indicating that the principal components contained most information of original data. Partial least squares discriminant ana-lysis marked 6 differential components in the decoction pieces. The established fingerprint and multicomponent determination are stable and reliable, and can provide a reference for the quality control of Radix Glycyrrhizae Radix et Rhizomae and fried Glycyrrhizae Radix et Rhizoma pieces.


Assuntos
Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas , Extratos Vegetais , Controle de Qualidade
12.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-879145

RESUMO

The research on the pharmacodynamic substance basis of traditional Chinese medicine(TCM) is a key scientific issue for the inheritance and development of TCM. At present, a large number of remarkable achievements have been made in the field of chemical components in Chinese medicine, however, another important aspect, namely the physical structure and mode of action of the multi-component assembly of TCM, has not been clearly understood and deeply studied. From the bottleneck of restricting material ba-sic research, we objectively analyzed the common cause of the existing problems. Based on the new discoveries and advances of active substances from TCM emerging in recent years, we extracted and summarized the concept of structural Chinese medicine, elaborated the basic ideas, main features and research modes, hoping to provide theoretical and practical references for the study on the pharmacodynamic substance basis and other research fields of TCM.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Medicina Tradicional Chinesa
13.
Chinese Herbal Medicines ; (4): 78-89, 2021.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-953683

RESUMO

Traditional Chinese medicines (TCMs), with a history of thousands of years, are widely used clinically with effective treatment. However, the drug delivery systems (DDSs) for TCMs remains major challenges due to the characteristics of multi-components including alkaloids, flavones, anthraquinones, glycosides, proteins, volatile oils and other types. Therefore, the novel preparations and technology of modern pharmaceutics is introduced to improve TCM therapeutic effects due to instability and low bioavailability of active ingredients. Salviae Miltiorrhizae Radix et Rhizoma, the radix and rhizomes of Salvia miltiorrhiza Bunge (Danshen in Chinese), is a well known Chinese herbal medicine for protecting the cardiovascular system, with active ingredients mainly including lipophilic tanshinones and hydrophilic salvianolic acids. In this review, this drug is taken as an example to present challenges and strategies in progress of DDSs for TCMs. This review would also summary the characteristics of active ingredients in it including physicochemical properties and pharmacological effects. The purpose of this review is to provide inspirations and ideas for the DDSs designed from TCMs by summarizing the advances on DDSs for both single- and multi-component from Danshen.

14.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-922768

RESUMO

Chansu has demonstrated adverse reactions in clinical settings, which is associated with its toxicity and limits its clinical applications. But there are methodological limitations for drug safety evaluation. In the current study, ultra-high performance liquid chromatography, lipidomic profiling, and molecular docking were used to systemically assess Chansu-induced acute inflammatory irritation and further identify the underlying drug targets. Compared with the EtOAc extract, Chansu water fraction containing indolealkylamines caused acute inflammatory irritation in rats, including acute pain (spontaneous raising foot reaction), and inflammation (paw edema). At the molecular level, lipids analysis revealed significantly higher levels of pro-inflammatory mediators of the COX and LOX pathways. However, anti-inflammatory mediators from the CYP 450, ALA, and DHA pathways markedly decreased after exposure to Chansu water fraction. Moreover, four indolealkylamines from Chansu showed a high theoretical affinity to a known irritation target, 5-HT


Assuntos
Animais , Ratos , Bufanolídeos , Edema/tratamento farmacológico , Inflamação , Lipidômica , Simulação de Acoplamento Molecular , Água
15.
Commun Biol ; 3(1): 569, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-33051587

RESUMO

There is an increasing demand for rapid, effective methods to identify and detect protein micro- and nano-crystal suspensions for serial diffraction data collection at X-ray free-electron lasers or high-intensity micro-focus synchrotron radiation sources. Here, we demonstrate a compact multimodal, multiphoton microscope, driven by a fiber-based ultrafast laser, enabling excitation wavelengths at 775 nm and 1300 nm for nonlinear optical imaging, which simultaneously records second-harmonic generation, third-harmonic generation and three-photon excited ultraviolet fluorescence to identify and detect protein crystals with high sensitivity. The instrument serves as a valuable and important tool supporting sample scoring and sample optimization in biomolecular crystallography, which we hope will increase the capabilities and productivity of serial diffraction data collection in the future.


Assuntos
Cristais Líquidos , Microscopia de Fluorescência por Excitação Multifotônica , Modelos Moleculares , Proteínas/química , Cristalização/métodos , Dispositivos Lab-On-A-Chip , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Conformação Proteica , Reprodutibilidade dos Testes , Relação Estrutura-Atividade
16.
Soft Matter ; 16(37): 8547-8553, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32909579

RESUMO

The time-resolved dynamic assembly and the structures of protein liquid dense clusters (LDCs) were analyzed under pulsed electric fields (EFs) applying complementary polarized and depolarized dynamic light scattering (DLS/DDLS), optical microscopy, and transmission electron microscopy (TEM). We discovered that pulsed EFs substantially affected overall morphologies and spatial distributions of protein LDCs and microcrystals, and affected the phase diagrams of LDC formation, including enabling protein solutions to overcome the diffusive flux energy barrier to phase separate. Data obtained from DLS/DDLS and TEM showed that LDCs appeared as precursors of protein crystal nuclei, followed by the formation of ordered structures within LDCs applying a pulsed EF. Experimental results of circular dichroism spectroscopy provided evidence that the protein secondary structure content is changing under EFs, which may consequently modulate protein-protein interactions, and the morphology, dimensions, and internal structure of LDCs. Data and results obtained unveil options to modulate the phase diagram of crystallization, and physical morphologies of protein LDCs and microcrystals by irradiating sample suspensions with pulsed EFs.


Assuntos
Proteínas , Cristalização , Difusão Dinâmica da Luz , Microscopia Eletrônica de Transmissão , Estrutura Secundária de Proteína
17.
Nat Prod Bioprospect ; 10(4): 209-220, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32524465

RESUMO

Alstonia scholaris (L.) R. Br., an evergreen tropical plant rich in indole alkaloids with significant physiological activity, is traditionally used to treat respiratory diseases in China. This study was conducted to establish the toxicity profile of the alkaloid extract (TA) of A. scholaris leaves in non-rodents. After oral administration of a single dose (4 g/kg.bw), a number of transient symptoms, such as unsteady gait, drooling, emesis, and reddening of peri-oral mucosa, were observed, but no treatment-related mortality. A sub-chronic toxicity study with a range of doses of TA (20, 60 and 120 mg/kg.bw) was conducted for a 13-week treatment period, followed by 4-week recovery observation. Except for emesis and drooling in majority of animals in 120 mg/kg.bw treatment group, no clinical changes were observed in TA-treated animals. Data from electrocardiography, bone marrow, urine, fecal, hematology and clinical chemistry analyses were comparable between TA-treated and control animals. No significant differences in the relative organ weights and histopathological characteristics were evident between the TA-treated and control groups. Accordingly, the non-observed-adverse-effect-level (NOAEL) of TA was established as 120 mg/kg.bw. Our results add further knowledge to the safety database for indole alkaloid extracts from A. scholaris with potential utility as novel drug candidates.

18.
Nat Prod Bioprospect ; 10(3): 119-129, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32356224

RESUMO

Indole alkaloids extract (IAAS) was prepared from leaves of Alstonia scholaris (L.) R. Br., an evergreen tropical plant widely distributed throughout the world. This plant has been used historically by the Dai ethnic people of China to treat respiratory diseases. This study evaluated the genotoxicity and safety pharmacology of IAAS to support clinical use. The bacterial reverse mutation (Ames) test, in vitro mammalian chromosomal aberration test, and in vivo mammalian erythrocyte micronucleus (MN) test were performed to evaluate genotoxicity. Mice were administered IAAS (240, 480, or 960 mg/kg bw) once orally to observe adverse central nervous system effects. Furthermore, beagle dogs were administered IAAS (10, 30, 60 mg/kg bw) once via the duodenum to evaluate its effects on the cardiovascular and respiratory systems. IAAS with or without S9-induced metabolic activation showed no genotoxicity in the Ames test up to 500 µg/plate, in the mammalian chromosomal aberration test up to 710 µg/mL, or in the MN test up to 800 mg/kg bw. No abnormal neurobehavioral effects were observed in mice following treatment with up to 960 mg/kg bw of IAAS. Moreover, blood pressure, heart rate, electrocardiogram parameters, and depth and rate of breathing in anesthetized beagle dogs did not differ among the IAAS doses or from the vehicle group. These data indicated that IAAS did not induce mutagenicity, clastogenicity, or genotoxicity, and no pharmaco-toxicological effects were observed in the respiratory, cardiovascular, or central nervous systems. Our results increased understanding of safety considerations associated with IAAS, and may indicate that IAAS is a possible drug candidate.

19.
Nat Prod Bioprospect ; 10(2): 77-88, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32236848

RESUMO

Alstonia scholaris (L.) R. Br. (Apocynaceae) is an evergreen tree that has been used to treat lung diseases. In this study, the toxicity profile of indole alkaloids from leaves of A. scholaris was investigated. In acute toxicity tests, mice were administered total alkaloids (TA) and five indole alkaloids. In a chronic toxicity test, rats were continuously administered TA (50, 100, and 300 mg/kg bw) for 13 weeks, followed by a 4-week recovery. A single administration of TA affected the behavior of mice, and at 12.8 g/kg bw, prone position, shortness of breath, wheezing, and convulsion were observed. The half-lethal dose (LD50) in mice was 5.48 g/kg bw, almost 2740 times the clinical dose in humans. Among the five indole alkaloids, the maximum tolerance dose in mice ranged from 0.75 to 4 g/kg bw. The TA-treated rats did not die and showed no adverse effects or dose-dependent changes in weight or food and water consumption, despite fluctuations in hematological and biochemical parameters compared with historical data. Furthermore, both gross and histopathological observations revealed no abnormalities in any organ. With daily oral administration to rats, the non-observed-adverse-effect-level of TA was 100 mg/kg bw. The results indicate that TA is safe for clinical use.

20.
Chinese Journal of Neurology ; (12): 152-156, 2020.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-870782

RESUMO

Both autoimmune epilepsy and autoimmune encephalitis are new clinical concepts proposed in recent years with the development of neuroimmunology.Is it appropriate for the patients with new-onset epileptic seizures and positive neuron antibodies diagnosed as autoimmune encephalitis or autoimmune epilepsy? There are still disputes and misunderstandings.Because there are usually some common anti-neuronal antibodies detected in the serum or cerebrospinal fluid of them both,and additionally their clinical manifestations have certain overlaps,such as drug resistant epilepsy and cognitive impairment,both concepts are often confused in clinical practice,resulting in unnecessary excessive long-term anti-epileptic treatment.This review interprets the differences and connections between the two diseases on concepts,epidemiology,pathogenesis and related risk factors,clinical manifestations,auxiliary examination,treatment and prognosis.

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