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1.
Phytomedicine ; 126: 155452, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38422650

RESUMEN

BACKGROUND: Depression is a common and recurrent neuropsychiatric disorder. Recent studies have shown that the N-methyl-d-aspartate (NMDA) receptor (NMDAR) is involved in the pathophysiology of depression. Previous studies have found that Kaji-ichigoside F1 (KF1) has a protective effect against NMDA-induced neurotoxicity. However, the antidepressant mechanism of KF1 has not been confirmed yet. PURPOSE: In the present study, we aimed to evaluate the rapid antidepressant activity of KF1 and explore the underlying mechanism. STUDY DESIGN: First, we explored the effect of KF1 on NMDA-induced hippocampal neurons and the underlying mechanism. Second, depression was induced in C57BL/6 mice via chronic unpredictable mild stress (CUMS), and the immediate and persistent depression-like behavior was evaluated using the forced swimming test (FST) after a single administration of KF1. Third, the contributions of NMDA signaling to the antidepressant effect of KF1 were investigated using pharmacological interventions. Fourth, CUMS mice were treated with KF1 for 21 days, and then their depression-like behaviors and the underlying mechanism were further explored. METHODS: The FST was used to evaluate immediate and persistent depression-like behavior after a single administration of KF1 with or without NMDA pretreatment. The effect of KF1 on depressive-like behavior was investigated in CUMS mice by treating them with KF1 once daily for 21 days through the sucrose preference test, FST, open field test, and tail suspension test. Then, the effects of KF1 on the morphology and molecular and functional phenotypes of primary neuronal cells and hippocampus of mice were investigated by hematoxylin-eosin staining, Nissl staining, propidium iodide staining, TUNEL staining, Ca2+ imaging, JC-1 staining, ELISA, immunofluorescence analysis, RT-PCR, and Western blot. RESULTS: KF1 could effectively improve cellular viability, reduce apoptosis, inhibit the release of LDH and Ca2+, and increase the mitochondrial membrane potential and the number of dendritic spines numbers in hippocampal neurons. Moreover, behavioral tests showed that KF1 exerted acute and sustained antidepressant-like effects by reducing Glu-levels and ameliorating neuronal damage in the hippocampus. Additionally, in vivo and in vitro experiments revealed that PSD95, Syn1, α-amino-3­hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), and brain-derived neurotrophic factor (BDNF) were upregulated at the protein level, and BDNF and AMPA were upregulated at the mRNA level. NR1 and NR2A showed the opposite trend. CONCLUSION: These results confirm that KF1 exerts rapid antidepressant effects mainly by activating the AMPA-BDNF-mTOR pathway and inhibiting the NMDAR-CaMKIIα pathway. This study serves as a new reference for discovering rapid antidepressants.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo , Depresión , Ratones , Animales , Depresión/metabolismo , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico/metabolismo , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico/farmacología , Factor Neurotrófico Derivado del Encéfalo/metabolismo , N-Metilaspartato/metabolismo , N-Metilaspartato/farmacología , Ratones Endogámicos C57BL , Antidepresivos/farmacología , Antidepresivos/uso terapéutico , Serina-Treonina Quinasas TOR/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Hipocampo , Estrés Psicológico/tratamiento farmacológico , Modelos Animales de Enfermedad
2.
J Ethnopharmacol ; 325: 117619, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38272103

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Calcium oxalate (CaOx) kidney stones are widely acknowledged as the most prevalent type of urinary stones, with high incidence and recurrence rates. Incarvillea diffusa Royle (ID) is a traditionally used medicinal herb in the Miao Minzu of Guizhou province, China, for treating urolithiasis. However, the active components and the underlying mechanism of its pharmacodynamic effects remain unclear. AIM OF THE STUDY: This study aimed to investigate the potential inhibitory effect of the active component of ID on the formation of CaOx nephrolithiasis and elucidate the underlying mechanism. MATERIALS AND METHODS: In vivo, a CaOx kidney stone model was induced in Sprague-Dawley (SD) rats using an ethylene glycol and ammonium chloride protocol for four weeks. Forty-eight male SD rats were randomly assigned to 6 groups (n = 8): blank group, model group, apocynin group, and low, medium, and high dose of ID's active component (IDW) groups. After three weeks of administration, rat urine, serum, and kidney tissues were collected. Renal tissue damage and crystallization, Ox, BUN, Ca2+, CRE, GSH, MDA, SOD contents, and levels of IL-1ß, IL-18, MCP-1, caspase-1, IL-6, and TNF-α in urine, serum, and kidney tissue were assessed using HE staining and relevant assay kits, respectively. Protein expression of Nrf2, HO-1, p38, p65, and Toll-4 in kidney tissues was quantified via Western blot. The antioxidant capacities of major compounds were evaluated through DPPH, O2·-, and ·OH radical scavenging assays, along with their effects on intracellular ROS production in CaOx-induced HK-2 cells. RESULTS: We found that IDW could significantly reduce the levels of CRE, GSH, MDA, Ox, and BUN, and enhancing SOD activity. Moreover, it could inhibit the secretion of TNF-α, IL-1ß, IL-18, MCP-1, caspase-1, and decreased protein expression of Nrf2, HO-1, p38, p65, and Toll-4 in renal tissue. Three major compounds isolated from IDW exhibited promising antioxidant activities and inhibited intracellular ROS production in CaOx-induced HK-2 cells. CONCLUSIONS: IDW facilitated the excretion of supersaturated Ca2+ and decreased the production of Ox, BUN in SD rat urine, and mitigated renal tissue damage by regulating Nrf2/HO-1 signaling pathway. Importantly, the three major compounds identified as active components of IDW contributed to the inhibition of CaOx nephrolithiasis formation. Overall, IDW holds significant potential for treating CaOx nephrolithiasis.


Asunto(s)
Oxalato de Calcio , Nefrolitiasis , Ratas , Masculino , Animales , Oxalato de Calcio/orina , Especies Reactivas de Oxígeno/metabolismo , Interleucina-18/efectos adversos , Interleucina-18/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Antioxidantes/efectos adversos , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa/metabolismo , Nefrolitiasis/inducido químicamente , Nefrolitiasis/tratamiento farmacológico , Riñón/metabolismo , Superóxido Dismutasa/metabolismo , Caspasas/metabolismo
3.
Molecules ; 28(5)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36903552

RESUMEN

Hydrogen-bonding catalytic reactions have gained great interest. Herein, a hydrogen-bond-assisted three-component tandem reaction for the efficient synthesis of N-alkyl-4-quinolones is described. This novel strategy features the first proof of polyphosphate ester (PPE) as a dual hydrogen-bonding catalyst and the use of readily available starting materials for the preparation of N-alkyl-4-quinolones. The method provides a diversity of N-alkyl-4-quinolones in moderate to good yields. The compound 4h demonstrated good neuroprotective activity against N-methyl-ᴅ-aspartate (NMDA)-induced excitotoxicity in PC12 cells.


Asunto(s)
Quinolonas , Ratas , Animales , Quinolonas/química , Enlace de Hidrógeno , Catálisis , Hidrógeno , 4-Quinolonas
4.
Molecules ; 28(4)2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-36838533

RESUMEN

Pyrola corbieri Levl has been used to strengthen bones and nourish the kidney (the kidney governs the bone and is beneficial to the brain) by the local Miao people in China. However, the functional components and neurotrophic activity have not been reported. A new acidic homogeneous heteropolysaccharide named LTC-1 was obtained and characterized by periodate oxidation, Smith degradation, partial acid hydrolysis, GC-MS spectrometry, methylation analysis, and Fourier transform infrared spectroscopy, and its molecular weight was 3239 Da. The content of mannuronic acid (Man A) in LTC-1 was 46%, and the neutral sugar was composed of L-rhamnose (L-Rha), L-arabinose (L-Ara), D-xylose (D-Xyl), D-mannose (D-Man), D-glucose (D-Glc) and D-galactose (D-Gal) with a molar ratio of 1.00:3.63:0.86:1.30:6.97:1.30. The main chain of LTC-1 was composed of Glc, Gal, Man, Man A and the branched chain Ara, Glc, Gal. The terminal residues were composed of Glc and Gal. The main chain and branched chains were linked by (1→5)-linked-Ara, (1→3)-linked-Glc, (1→4)-linked-Glc, (1→6)-linked-Glc, (1→3)-linked-Gal, (1→6)-linked-Gal, (1→3, 6)-linked-Man and ManA. Meanwhile, neurotrophic activity was evaluated through PC12 and primary hippocampal neuronal cell models. LTC-1 exhibited neurotrophic activity in a concentration-dependent manner, which significantly induced the differentiation of PC12 cells, promoted the neurite outgrowth of PC12 cells, enhanced the formation of the web architecture of dendrites, and increased the density of dendritic spines in hippocampal neurons and the expression of PSD-95. These results displayed significant neurotrophic factor-like activity of LTC-1, which suggests that LTC-1 is a potential treatment option for neurodegenerative diseases.


Asunto(s)
Pyrola , Humanos , Polisacáridos/química , Carbohidratos , Galactosa , Glucosa
5.
J Ethnopharmacol ; 301: 115832, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36283636

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Gastrodia elata Blume (GE) is a Chinese medicinal herb commonly used to treat central nervous system-related diseases, including headaches, dizziness, epilepsy, numbness of the limbs and depression. AIM OF THE STUDY: Microbial-based fermentation has been successfully used to increase the extract efficiency of medicinal herbs in recent years. However, no study has hitherto explored the anti-depressant-like effect of GE processed by microorganisms. Herein, this subject aimed to clarify the anti-depressant-like effect of fermented Gastrodia elata Bl. (FGE) and its active chemical constituents. MATERIALS AND METHODS: The chronic unpredictable mild stress (CUMS) model, a well-established animal model of depression, was induced in Kunming (KM) mice. The mice were administrated with FGE for 3 weeks. The sucrose preference test (SPT), open field test (OFT) and tail suspension test (TST) were conducted. Moreover, the levels of serotonin (5-HT) and dopamine (DA) in brain tissue homogenates, the concentration of Ca2+ and the activity of MAO in serum, H&E and Nissl staining in the hippocampus, and the hippocampus protein expressions of BDNF, NMDAR1, NMDAR2A and NMDAR2B relevant to depression were detected. Furthermore, chemical constituents of FGE were further isolated, and the protective activity of the obtained compounds against NMDA-induced PC-12 cell damage was assessed. RESULTS: FGE could alleviate the depression state in CUMS-induced mice and reduce apoptosis of neuronal cells in the hippocampus. Furthermore, FGE could improve the contents of 5-HT, DA and decrease the concentration of Ca2+ and MAO activity in brain tissue and serum compared with the control group. It could reverse the decreased expression of BDNF, NMDAR2A and NMDAR2B and increase NMDAR1 protein expression. Investigation of the active constituents from FGE yielded two new compounds, (4-(((4-ethoxybenzyl) oxy)methyl)-phenol 1 and 3-((4-hydroxy benzyl)oxy)propane-1,2-diol) 2, with twelve known compounds (3-14). The compounds (3-((4-hydroxybenzyl)oxy)propane-1,2-diol 2, 4, 4'-dihydroxyd iphenyl methane 3, and bungein A 4) protected against NMDA-induced PC-12 cells damage. CONCLUSION: This study demonstrated that FGE could improve the depressive behavior of CUMS-induced mice and exert a protective effect on nerve cells in the brain. Importantly, compounds 2-4 are the active components of FGE. Overall, the above findings suggest that FGE has huge prospects for application in treating depression-related diseases.


Asunto(s)
Gastrodia , Animales , Ratones , Antidepresivos/farmacología , Antidepresivos/uso terapéutico , Conducta Animal , Factor Neurotrófico Derivado del Encéfalo , Depresión/tratamiento farmacológico , Depresión/metabolismo , Modelos Animales de Enfermedad , Dopamina/metabolismo , Gastrodia/química , Monoaminooxidasa/metabolismo , N-Metilaspartato , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Extractos Vegetales/química , Propano/farmacología , Serotonina/metabolismo , Estrés Psicológico/tratamiento farmacológico , Receptores de N-Metil-D-Aspartato/metabolismo
6.
Int J Mol Sci ; 23(24)2022 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-36555790

RESUMEN

Kaji-ichigoside F1 (KF1), a natural oleanane-type triterpenoid saponin, is the main active constituent from Rosa roxburghii. In the southwest regions of China, particularly in Guizhou Province, this plant was used as a Miao ethnic medicine to prevent and treat dyspepsia, dysentery, hypoimmunity, and neurasthenia. In the present study, the neuroprotective effect of KF1 was evaluated against N-methyl-D-aspartate (NMDA)-induced neurotoxicity in vivo and in vitro. An NMDA-induced PC12 cell neurotoxicity assay showed that KF1 effectively improved cellular viability, inhibited the release of lactate dehydrogenase (LDH), and reduced cell apoptosis. Furthermore, KF1-treated NMDA-induced excitotoxicity mice displayed a remarkable capacity for improving spatial learning memory in the Y-maze and Morris water maze tests. In addition, KF1 increased the levels of the neurotransmitters 5-hydroxytryptamine, dopamine, and monoamine oxidase and reduced the calcium ion concentration in the hippocampus of mice. Hematoxylin and eosin and Nissl staining indicated that KF1 effectively reduced the impairment of neurons. Furthermore, Western blot assays showed that KF1 decreased NMDAR1 expression. In contrast, the NMDAR2B (NR2B), glutamate receptor (AMPA), TrkB, protein kinase B (AKT), mammalian target of rapamycin (mTOR), PSD95, and synapsin 1 were upregulated in NMDA-induced PC12 cells and an animal model. These results suggest that KF1 has a remarkable protective effect against NMDA-induced neurotoxicity, which is directly related to the regulation of the NMDA receptor and the activation of the α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor (AMPAR) and BDNF/AKT/mTOR signaling pathways.


Asunto(s)
Fármacos Neuroprotectores , Proteínas Proto-Oncogénicas c-akt , Animales , Ratones , Ratas , Factor Neurotrófico Derivado del Encéfalo/metabolismo , N-Metilaspartato/metabolismo , Neuroprotección , Fármacos Neuroprotectores/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo
7.
Artículo en Inglés | MEDLINE | ID: mdl-35497912

RESUMEN

The deficiency of traditional calcium preparation will gradually be replaced by the new type of calcium preparation. Rosa roxburghii fruit (R. roxburghii) is popular for its rich nutrients and functional ingredients. The fermentation broth of R. roxburghii, involving amino acids, flavonoids, triterpenes, polysaccharides, and other compounds, is favorable for calcium chelation. Thus, this study fabricated calcium-incorporated R. roxburghii (FECa) and further illustrated its efficacy on bone mineral density (BMD) in rats. The calcium holding capacity of FECa was identified and confirmed using AAS. Ion complexation of FECa was characterized using 1H-NMR, UV, SEM and EDS, and FTIR. The calcium contents of femurs were increased by 36%, and the bone trabeculae of femurs were significantly increased. Net calcium balance was enhanced to further improve BMD by oral administration of FECa. The above results indicate that FECa can be a potential and efficient calcium supplementation agent.

8.
Bioorg Chem ; 95: 103508, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31927315

RESUMEN

Diosgenone [(20S,22R,25R)-spirost-4-en-3-one, C27H40O3] has been considered as a potential therapeutic alternative remedy for malaria. An efficient and economical approach of microbial transformation with diosgenin to diosgenone by the yeast strain Wickerhamomyces anomalus JQ-1 from Naxi traditional Jiu Qu was developed in this study. Chromatographic analysis confirmed that 85% of 0.1 mM diosgenin was transformed to diosgenone within 72 h. This research demonstrates that diosgenin could be converted to diosgenone through two-step pathway including 3ß-hydroxyl oxidation and double bond isomerization rather than through one-step pathway, which prompted a further inference that the oxidation activity in W. anomalus JQ-1 has the same function with the Oppenauer-type oxidation which can convert diosgenin into diosgenone. Gaining specific functional strains from traditional fermented products will be a potential direction and ethnobotanical researches could provide helps with discovery and utilization of microbial resources.


Asunto(s)
Diosgenina/metabolismo , Saccharomycetales/química , Compuestos de Espiro/metabolismo , Triterpenos/metabolismo , China , Diosgenina/química , Relación Dosis-Respuesta a Droga , Estructura Molecular , Saccharomycetales/aislamiento & purificación , Saccharomycetales/metabolismo , Compuestos de Espiro/química , Relación Estructura-Actividad , Triterpenos/química
9.
Sensors (Basel) ; 19(9)2019 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-31086068

RESUMEN

In this paper, we propose a novel fuzzy expectation maximization (FEM) based Takagi-Sugeno (T-S) fuzzy particle filtering (FEMTS-PF) algorithm for a passive sensor system. In order to incorporate target spatial-temporal information into particle filtering, we introduce a T-S fuzzy modeling algorithm, in which an improved FEM approach is proposed to adaptively identify the premise parameters, and the model probability is adjusted by the premise membership functions. In the proposed FEM, the fuzzy parameter is derived by the fuzzy C-regressive model clustering method based on entropy and spatial-temporal characteristics, which can avoid the subjective influence caused by the artificial setting of the initial value when compared to the traditional FEM. Furthermore, using the proposed T-S fuzzy model, the algorithm samples particles, which can effectively reduce the particle degradation phenomenon and the parallel filtering, can realize the real-time performance of the algorithm. Finally, the results of the proposed algorithm are evaluated and compared to several existing filtering algorithms through a series of Monte Carlo simulations. The simulation results demonstrate that the proposed algorithm is more precise, robust and that it even has a faster convergence rate than the interacting multiple model unscented Kalman filter (IMMUKF), interacting multiple model extended Kalman filter (IMMEKF) and interacting multiple model Rao-Blackwellized particle filter (IMMRBPF).

10.
J Ethnobiol Ethnomed ; 14(1): 74, 2018 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-30486880

RESUMEN

BACKGROUND: Bai people in the Dali Prefecture of Northwest Yunnan, China, have a long history of using plant extracts to dye their traditional costumes and maintain this culture for posterity. However, the development of modern technology, while vastly improving the dyeing efficiency, is also replacing indigenous knowledge which threatens the indigenous practice, causing the latter disappearing gradually. This study sought to examine the indigenous knowledge of plants used for textile dyeing in Bai communities, so as to provide a foundation for their sustainable development. METHODS: We conducted a semi-structured interview among 344 informants (above age 36) selected through a snowball sampling method. Free lists and participant observation were used as supplementary methods for the interviews. Three quantitative indicators (informant consensus factor [ICF], use frequency, and cultural importance index [CI]) were used to evaluate the indigenous knowledge of the dye-yielding plants. RESULTS: Twenty-three species belonging to 19 plant taxonomic families were used for dye by Bai communities. We summarized them into four life forms, eight used parts, five colors, three processing methods, and four dyeing methods. Among them, Strobilanthes cusia (Nees) O. Kuntze was the most traditional dyeing plant and has an important cultural value. Location, age, and gender were found to have a significant effect on indigenous knowledge, and the dyeing knowledge was dynamic and influenced by social factors. CONCLUSIONS: Diverse plant resources and rich indigenous knowledge of textile dyeing persist at settlements of Bai communities in Dali Prefecture. However, high labor costs and thinning market of traditional products that use plant dye cause repulsion toward traditional practice. To that, a good income in other profession attracts indigenous people to shift from their tradition of making plant-based dye and associated cultural systems at risk of extinction. More research for market development for products that use plant-based dye is necessary for the conservation of this valuable knowledge and biodiversity protection in Bai communities.


Asunto(s)
Colorantes , Conocimiento , Plantas , Textiles , Adulto , Anciano , Anciano de 80 o más Años , Biodiversidad , China/etnología , Etnobotánica , Femenino , Humanos , Masculino , Persona de Mediana Edad
11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 25(2): 426-430, 2017 Apr.
Artículo en Chino | MEDLINE | ID: mdl-28446287

RESUMEN

OBJECTIVE: To investigate the prognostic significance of Follicular Lymphoma International Prognostic Index 2 (FLIPI2) in FL patients treated with rituximab maintenance. METHODS: A tatol of 140 newly diagnosed FL patients who received Rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) chemotherapy in our department were retrospectively analyzed from December 2002 to December 2014. Among 140 patients with FL 122 patients achieved response, from them 56 patients received R maintenance (RM) every 2 months for median 8 times (RM group) while the rest 66 patients did not receive further anti-lymphoma treatment (non-RM group). RESULTS: There was no statistical difference in age, sex, pathologic grading, staging, FLIPI or FLIPI2 between RM and non-RM groups. The 2-year progression-free survival (PFS) of RM and non-RM groups were 89.7% and 77.6% (P=0.043) while the 2-year overall survival were 100% and 98.6% (P=0.131). FLIPI2 is a significant prognostic model either in the total cohort, RM or non-RM groups (P<0.001 all). In subgroup analysis, RM was able to decrease disease progression in low and intermediate-risk group of FLIPI2, while the 2-year PFS of RM and non-RM groups in high-risk group were similar (55.6% vs 46.9%)(P=0.920). CONCLUSION: FLIPI2 presents robust prognostic significance either in RM or OBS patients, the patients in FLIPI2 low and intermediate-risk group may benefite from RM, but the role of RM in high-risk patients should be further to investigate.


Asunto(s)
Antineoplásicos Inmunológicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfoma Folicular/tratamiento farmacológico , Rituximab/uso terapéutico , Anticuerpos Monoclonales de Origen Murino/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Ciclofosfamida/administración & dosificación , Supervivencia sin Enfermedad , Doxorrubicina/administración & dosificación , Humanos , Prednisona/administración & dosificación , Pronóstico , Estudios Retrospectivos , Vincristina/administración & dosificación
12.
Sensors (Basel) ; 17(5)2017 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-28448470

RESUMEN

Novel auxiliary truncated unscented Kalman filtering (ATUKF) is proposed for bearings-only maneuvering target tracking in this paper. In the proposed algorithm, to deal with arbitrary changes in motion models, a modified prior probability density function (PDF) is derived based on some auxiliary target characteristics and current measurements. Then, the modified prior PDF is approximated as a Gaussian density by using the statistical linear regression (SLR) to estimate the mean and covariance. In order to track bearings-only maneuvering target, the posterior PDF is jointly estimated based on the prior probability density function and the modified prior probability density function, and a practical algorithm is developed. Finally, compared with other nonlinear filtering approaches, the experimental results of the proposed algorithm show a significant improvement for both the univariate nonstationary growth model (UNGM) case and bearings-only target tracking case.

13.
Sensors (Basel) ; 17(2)2017 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-28212291

RESUMEN

Tracking the target that maneuvers at a variable turn rate is a challenging problem. The traditional solution for this problem is the use of the switching multiple models technique, which includes several dynamic models with different turn rates for matching the motion mode of the target at each point in time. However, the actual motion mode of a target at any time may be different from all of the dynamic models, because these models are usually limited. To address this problem, we establish a formula for estimating the turn rate of a maneuvering target. By applying the estimation method of the turn rate to the multi-target Bayes (MB) filter, we develop a MB filter with an adaptive estimation of the turn rate, in order to track multiple maneuvering targets. Simulation results indicate that the MB filter with an adaptive estimation of the turn rate, is better than the existing filter at tracking the target that maneuvers at a variable turn rate.

14.
Nat Prod Bioprospect ; 6(3): 183-6, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27095015

RESUMEN

Catalytic asymmetric formal synthesis of (-)-Triptophenolide and (+)-Triptolide have been achieved. Key reaction involves Palladium catalyzed asymmetric conjugate addition of aryl boronic acid to 3-methyl cyclohexe-1-none to form quaternary carbon. Claisen rearrangement and subsequent aldol reaction furnished trans-decaline key intermediate, which assured a formal total synthesis of (-)-Triptophenolide and (+)-Triptolide.

15.
Zhonghua Xue Ye Xue Za Zhi ; 35(6): 481-5, 2014 Jun.
Artículo en Chino | MEDLINE | ID: mdl-24985167

RESUMEN

OBJECTIVE: To compare the clinical efficacy and safety among different chemotherapeutic regimens in treatment of refractory/relapsed acute myeloid leukemia (AML). METHODS: The clinical data of 67 refractory/relapsed AML patients enrolled from September 2008 to April 2013 were collected. The differences of clinical outcome and adverse events among the patients treated with decitabine combined with DAG regimen, CAG regimen or "3+7" regimen were analyzed. RESULTS: Among 19 patients in decitabine treatment group, 5 (26.3%) achieved complete remission (CR), 4 (21.1%) partial remission (PR), with overall response rate (ORR) of 47.4 %. Of 26 patients in CAG regimen group, 8 (30.8%) achieved CR, 1 (3.8%) PR, with ORR of 34.6%. Of 22 patients in "3+7" regimen group, 4 (18.2%) achieved CR, with ORR of 18.2%. The ORR of decitabine group was significantly higher than that of "3+7" group (P<0.05). However, no significant difference of ORR was observed among the three groups (P>0.05). It was interesting to note that in decitabine group, the marrow blast counts were lower in CR patients compared with those in non-CR patients (P<0.05), while this was not found in "3+7" group (P>0.05) and CAG regimen group (P>0.05). Adverse events in the three groups were similar, mainly including myelosuppression, pulmonary infection, nausea, vomiting and liver dysfunction, and could be well tolerated. Followed- up to September 2013, the median overall survival (OS) of decitabine group, CAG regimen group and "3+7" group after relapse was 7.5, 4 and 3 months, respectively (P>0.05), while significant difference was obtained between decitabine group and "3+7" regimen group (P<0.05). CONCLUSION: Decitabine combined with DAG regimen is effective and well tolerated in refractory/relapsed AML patients who were unsuitable for intensive chemotherapy and hematopoietic stem cell transplantation, and the patients with low marrow blast counts are more suitable for the application of decitabine combined with DAG regimen.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Azacitidina/análogos & derivados , Leucemia Mieloide Aguda/tratamiento farmacológico , Adulto , Anciano , Azacitidina/administración & dosificación , Decitabina , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
16.
Org Lett ; 16(8): 2196-9, 2014 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-24697243

RESUMEN

High contents of curcusones A and B and trace amounts of spirocurcasone exist in the roots of Jatropha curcas. Here, a one-step semisynthesis method of spirocurcasone and pyracurcasone was built, not only resulted an increased yield of spirocurcasone but also produced pyracurcasone, which exhibited greater cytotoxicity compared to curcusones A and B. The plausible mechanism of the formation of pyracurcasone was proposed, and the proposed biogenetic origin for spirocurcasone by Taglialatela-Scafati was confirmed.


Asunto(s)
Diterpenos/síntesis química , Cisplatino/farmacología , Diterpenos/química , Diterpenos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Células HL-60 , Humanos , Jatropha/química , Estructura Molecular , Raíces de Plantas/química , Relación Estructura-Actividad
17.
Org Lett ; 15(15): 3902-5, 2013 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-23879614

RESUMEN

Four new phragmalin limonoids (chukfuransins A-D) were isolated from the twigs and leaves of Chukrasia tabularis. Chukfuransins A (1) and B (2) feature a unique C-15/C-20 linkage proposed to be built by a biogenetic pathway involving Michael addition. Chukfuransins C (3) and D (4) feature the C-15/C-21 linkage. Their structures and absolute configurations were established by NMR techniques and X-ray crystallographic analysis.


Asunto(s)
Furanos/química , Furanos/aislamiento & purificación , Limoninas/química , Limoninas/aislamiento & purificación , Meliaceae/química , Corteza de la Planta/química , Tallos de la Planta/química , Cristalografía por Rayos X , Limoninas/análisis , Espectroscopía de Resonancia Magnética , Estructura Molecular
18.
J Nat Prod ; 75(7): 1409-13, 2012 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-22742732

RESUMEN

Previous analyses of the naphthomycin biosynthetic gene cluster and a comparison with known naphthomycin-type products from Streptomyces sp. CS have suggested that new products can be found from this strain. In this study, screening by LC-MS of Streptomyces sp. CS products formed under different culture conditions revealed several unknown peaks in the product spectra of extracts derived from oatmeal medium cultures. Three new naphthomycins, naphthomycins L (1), M (2), and N (3), and the known naphthomycins A (4), E (5), and D (6) were obtained. The structures were elucidated using spectroscopic data from 1D and 2D NMR and HRESIMS experiments.


Asunto(s)
Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Antifúngicos/aislamiento & purificación , Naftoquinonas/aislamiento & purificación , Naftoquinonas/farmacología , Streptomyces/química , Streptomyces/genética , Antibacterianos/química , Antifúngicos/química , Antifúngicos/farmacología , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Familia de Multigenes , Naftoquinonas/química
19.
Molecules ; 15(6): 3993-7, 2010 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-20657420

RESUMEN

The strain T1BF was isolated from the old bast tissue of Taxus yunnanensis and determined to be a member of Talaromyces. The extracts from the solid fermentation of Talaromycessp. T1BF were purified and obtained three azaphilones, including a new one. They were identified on the basis of spectral data as 6alpha-hydroxy-7beta-methyl-8-oxo-3-((E)- prop-1-en-1-yl)-5,6,7,8-tetrahydro-1H-isochromen-7-yl-4'-hydroxy-2'-methoxy-6'-methyl- benzoate, named as kasanosin C (1), entonaemin A (2) and (+)-mitorubrin (3).


Asunto(s)
Benzopiranos/química , Pigmentos Biológicos/química , Talaromyces/química , Espectroscopía de Resonancia Magnética , Estructura Molecular
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