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Anthracenylidene is an intriguing structural unit with potential in various fields. The study presents a novel approach to introducing axial chirality into this all-carbon core skeleton through a remotely controlled desymmetrization strategy. A palladium-catalyzed enantioselective Heck arylation of exocyclic double bond of anthracene with two distinct substituents at the C10 position is harnessed to realize such a transformation. The judicious identification of the P-centrally chiral ligand is pivotal to ensure the competitive competence in reactivity and stereocontrol when the heteroatom handle is absent from the anthracenylidene skeleton. Both C10 mono- and disubstituted substrates were compatible for the established catalytic system, and structurally diverse anthracenylidene-based frameworks were forged with good-to-high enantiocontrol. The subsequent derivatization of the obtained products yielded a valuable array of centrally and axially chiral molecules, thus emphasizing the practicality of this chemistry. DFT calculations shed light on the catalytic mechanism and provided insights into the origin of the experimentally observed enantioselectivity for this reaction.
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Herbivore-associated molecular patterns (HAMPs) enable plants to recognize herbivores and may help plants adjust their defense responses. Here, we report on herbivore-induced changes in a protein disulfide isomerase (PDI) widely distributed across arthropods. PDI from the spider mite Tetranychus evansi (TePDI), a mesophyll-feeding agricultural pest worldwide, triggered immunity in multiple Solanaceae plants. TePDI-mediated cell death in Nicotiana benthamiana required the plant signaling proteins SGT1 (suppressor of the G2 allele of skp1) and HSP90 (heat shock protein 90), but was suppressed by spider mite effectors Te28 and Te84. Moreover, PDIs from phylogenetically distinct herbivorous and nonherbivorous arthropods triggered plant immunity. Finally, although PDI-induced plant defenses impaired the performance of spider mites on plants, RNAi experiments revealed that PDI genes are essential for the survival of mites and whiteflies. Our findings indicate that plants recognize evolutionarily conserved HAMPs to activate plant defense and resist pest damage, pointing to opportunities for broad-spectrum pest management.
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Herbivoria , Tetranychidae , Animales , Proteína Disulfuro Isomerasas/genética , Plantas , Nicotiana/genética , Proteínas de Plantas/genética , Tetranychidae/fisiologíaRESUMEN
Ventricular arrhythmias are the leading cause of sudden cardiac death in patients after myocardial infarction (MI). Connexin43 (Cx43) is the most important gap junction channel-forming protein in cardiomyocytes. Dysfunction of Cx43 contributes to impaired myocardial conduction and the development of ventricular arrhythmias. Following an MI, Cx43 undergoes structural remodeling, including expression abnormalities, and redistribution. These alterations detrimentally affect intercellular communication and electrical conduction within the myocardium, thereby increasing the susceptibility to post-infarction ventricular arrhythmias. Emerging evidence suggests that post-translational modifications play essential roles in Cx43 regulation after MI. Therefore, Cx43-targeted management has the potential to be a promising protective strategy for the prevention and treatment of post infarction ventricular arrhythmias. In this article, we primarily reviewed the regulatory mechanisms of Cx43 mediated post-translational modifications on post-infarction ventricular arrhythmias. Furthermore, Cx43-targeted therapy have also been discussed, providing insights into an innovative treatment strategy for ventricular arrhythmias after MI.
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Conexina 43 , Infarto del Miocardio , Humanos , Arritmias Cardíacas/metabolismo , Conexina 43/genética , Conexina 43/metabolismo , Infarto del Miocardio/complicaciones , Infarto del Miocardio/metabolismo , Miocardio/metabolismo , Procesamiento Proteico-PostraduccionalRESUMEN
Chiral cyclobutene units are commonly found in natural products and biologically active molecules. Transition-metal-catalysis has been extensively used in asymmetric synthesis of such structures, while organocatalytic approaches remain elusive. In this study, bicyclo[1.1.0]butanes are involved in enantioselective transformation for the first time to offer a highly efficient route toward cyclobutenes with good regio- and enantiocontrol. The utilization of N-triflyl phosphoramide as a chiral Brønsted acid promoter enables this isomerization process to proceed under mild conditions with low catalyst loading as well as good functional group compatibility. The resulting chiral cyclobutenes could serve as platform molecules for downstream manipulations with excellent reservation of stereochemical integrity, demonstrating the synthetic practicality of the developed method. Control experiments have also been performed to verify the formation of a key carbocation intermediate at the benzylic position.
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Microbes play a key role in the biology, ecology, and evolution of arthropods. Despite accumulating data on microbial communities in arthropods that feed on plants using piercing-sucking mouthparts, we still lack a comprehensive understanding of the composition and assembly factors of the microbiota, particularly in field-collected spider mites. Here, we applied 16S rRNA amplicon sequencing to investigate the characters of the bacterial community in 140 samples representing 420 mite individuals, belonging to eight Tetranychus species (Acari: Tetranychidae) collected from 26 sites in China. The results showed that the bacterial composition of spider mites varied significantly among different species, locations, and plants. The environment showed a significant influence on the bacterial community of spider mites, with different relative contributions. Latitude and precipitation were found to be the main factors influencing the bacterial community composition. The dissimilarity of bacterial community and geographical distance between mite locations were significantly correlated. The assembly of spider mite bacterial communities seemed to be mainly influenced by stochastic processes. Furthermore, the symbiont Cardinium was found to be important in shaping the microbiota of many Tetranychus species. The relative abundance of Cardinium was > 50% in T. viennensis, T. urticae G, T. urticae R, and T. turkestani. Removing Cardinium reads from our analysis significantly changed Shannon diversity index and weighted beta diversity in these species. Altogether, this study provides novel insights into bacterial diversity patterns that contribute to our knowledge of the symbiotic relationships between arthropods and their bacterial communities.
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Artrópodos , Microbiota , Tetranychidae , Humanos , Animales , ARN Ribosómico 16S/genética , Bacteroidetes/genéticaRESUMEN
BACKGROUND: Diabetes is associated with myocardial fibrosis, while the underlying mechanisms remain elusive. The aim of this study is to investigate the underlying role of calcineurin/nuclear factor of activated T cell 3 (CaN/NFATc3) pathway and the Enhancer of zeste homolog 2 (EZH2) in diabetes-related myocardial fibrosis. METHODS: Streptozotocin (STZ)-injected diabetic rats were randomized to two groups: the controlled glucose (Con) group and the diabetes mellitus (DM) group. Eight weeks later, transthoracic echocardiography was used for cardiac function evaluation, and myocardial fibrosis was visualized by Masson trichrome staining. The primary neonatal rat cardiac fibroblasts were cultured with high-glucose medium with or without cyclosporine A or GSK126. The expression of proteins involved in the pathway was examined by western blotting. The nuclear translocation of target proteins was assessed by immunofluorescence. RESULTS: The results indicated that high glucose treatment increased the expression of CaN, NFATc3, EZH2 and trimethylates lysine 27 on histone 3 (H3K27me3) in vitro and in vivo. The inhibition of the CaN/NFATc3 pathway alleviated myocardial fibrosis. Notably, inhibition of CaN can inhibit the nuclear translocation of NFATc3, and the expression of EZH2 and H3K27me3 protein induced by high glucose. Moreover, treatment with GSK126 also ameliorated myocardial fibrosis. CONCLUSION: Diabetes can possibly promote myocardial fibrosis by activating of CaN/NFATc3/EZH2 pathway.
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Calcineurina , Diabetes Mellitus Experimental , Animales , Ratas , Diabetes Mellitus Experimental/complicaciones , Proteína Potenciadora del Homólogo Zeste 2/genética , Fibroblastos , Glucosa , Histonas , Factores de Transcripción NFATCRESUMEN
BACKGROUND: In 2017, surveillance for tickborne diseases in China led to the identification of a patient who presented to a hospital in Inner Mongolia with a febrile illness that had an unknown cause. The clinical manifestation of the illness was similar to that of tickborne encephalitis virus (TBEV) infection, but neither TBEV RNA nor antibodies against the virus were detected. METHODS: We obtained a blood specimen from the index patient and attempted to isolate and identify a causative pathogen, using genome sequence analysis and electron microscopy. We also initiated a heightened surveillance program in the same hospital to screen for other patients who presented with fever, headache, and a history of tick bites. We used reverse-transcriptase-polymerase-chain-reaction (RT-PCR) and cell-culture assays to detect the pathogen and immunofluorescence and neutralization assays to determine the levels of virus-specific antibodies in serum specimens from the patients. RESULTS: We found that the index patient was infected with a previously unknown segmented RNA virus, which we designated Alongshan virus (ALSV) and which belongs to the jingmenvirus group of the family Flaviviridae. ALSV infection was confirmed by RT-PCR assay in 86 patients from Inner Mongolia and Heilongjiang who presented with fever, headache, and a history of tick bites. Serologic assays showed that seroconversion had occurred in all 19 patients for whom specimens were available from the acute phase and the convalescent phase of the illness. CONCLUSIONS: A newly discovered segmented virus was found to be associated with a febrile illness in northeastern China. (Funded by the National Key Research and Development Program of China and the National Natural Science Foundation of China.).
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Enfermedades Transmisibles Emergentes/virología , Flaviviridae/aislamiento & purificación , Enfermedades por Picaduras de Garrapatas/virología , Adulto , Anciano , Animales , China/epidemiología , Enfermedades Transmisibles Emergentes/epidemiología , Fatiga/etiología , Femenino , Fiebre/etiología , Flaviviridae/clasificación , Flaviviridae/genética , Flaviviridae/ultraestructura , Cefalea/etiología , Humanos , Masculino , Microscopía Electrónica , Persona de Mediana Edad , Filogenia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Evaluación de Síntomas , Enfermedades por Picaduras de Garrapatas/complicaciones , Enfermedades por Picaduras de Garrapatas/epidemiología , Garrapatas/virologíaRESUMEN
The present study explored the effective components, functional targets, and mechanism of Sparganii Rhizoma(vinegar-processed Sparganii Rhizoma) in the treatment of hyperlipidemia based on network pharmacology and experimental verification. In the network pharmacology, the screening of active components, target prediction, and pathway enrichment analysis of Sparganii Rhizoma were carried out, followed by the comparison with targets and pathways related to hyperlipidemia. In the experimental verification, the hyperlipidemia model in rats was induced to detect hemorheological parameters and coagulation function. The liver index was observed by HE staining, and PCR technology was used to verify the results of the network pharmacological analysis. Compared with the model group, the Sparganii Rhizoma and vinegar-processed Sparganii Rhizoma groups showed decreased liver index(P<0.05), reduced liver lipid deposition, dwindled serum low-density lipoprotein cholesterol(LDL-c) level(P<0.05), diminished blood viscosity, and increased prothrombin time(PT), thrombin time(TT), and activated partial thrombin time(APTT)(P<0.05). As revealed by the PCR assay, Sparganii Rhizoma could affect LDL-c and high-density lipoprotein cholesterol(HDL-c) levels and reduce the inhibitory effect of cholesterol ester transporter by regulating the expression of Apol2, Apof, and Stab2, thereby treating hyperlipidemia. Vinegar-processed Sparganii Rhizoma could enhance triglyceride metabolism and cholesterol reversal by regulating the expression of Hmgcr, Hmgcs2, Abca1, Abcg1, Cyp7 b1, and Stab2. Compared with the Sparganii Rhizoma, the vinegar-processed one was potent in treating hyperlipidemia. The active components of Sparganii Rhizoma in the treatment of hyperlipidemia may be L-alpha-palmitin,(1S,2S)-1,2-bis(2-furyl)ethane-1,2-diol, cis-zimtsaeure, o-acetyl-p-cresol, sanleng, and 9-hexadecenoic acid. Based on the network pharmacology and experimental verification, this study preliminarily explored the potential active components and possible mechanism of Sparganii Rhizoma in the treatment of hyperlipidemia, which is expected to provide a certain basis for in-depth research on active components, mechanism, and clinical application.
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Medicamentos Herbarios Chinos , Hiperlipidemias , Ácido Acético , Animales , Colesterol , LDL-Colesterol/uso terapéutico , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Hiperlipidemias/tratamiento farmacológico , Hiperlipidemias/genética , Farmacología en Red , RatasRESUMEN
BACKGROUNDS: One of the most common complications in diabetic nephropathy is generation of high levels of ROS which can be regulated by herbal antioxidants. However, polyphenols like calycosin, the bioactive compound of Radix astragali suffer from low solubility and poor bioavailability. METHODS: Therefore, in the present study, calycosin-loaded nanoliposomes were fabricated and characterized by TEM, DLS and FTIR techniques. Afterwards, the drug loading (DL) and entrapment efficiency (EE), drug release, solubility, stability, and pharmacodynamic assays were performed. Finally, the antinephropathic effects of calycosin-loaded-nanoliposomes on mitochondria of kidney cells were explored by MTT, ROS, MDA, mitochondrial respiratory function assays. RESULTS: The result showed that the size, hydrodynamic radius, zeta potential, EE, and DL were, 80 nm, 133.99 ± 21.44 nm, - 20.53 ± 3.57, 88.37 ± 2.28%, and 7.48 ± 1.19%, respectively. The outcomes of in vitro release assay showed that calycosin-loaded nanoliposomes were significantly slow-release in dialysis media with pH 1.2, pH 6.9 and pH 7.4, at about 30 min, the dissolution of calycosin from nanoliposome became almost complete, and after 2 months, the calycosin-loaded nanoliposomes were still stable. Pharmacokinetic assay revealed that the AUC0-t of calycosin in calycosin-loaded nanoliposome group was 927.39 ± 124.91 µg/L*h, which was 2.26 times than that of the free calycosin group (**P < 0.01). Additionally, the MRT0-t and t1/2 of calycosin in the calycosin-loaded nanoliposome group were prolonged by 1.54 times and 1.33 times than that of free calycosin group, respectively (*P < 0.05). Finally, it was shown that calycosin-loaded nanoliposomes regulated the viability, ROS production, lipid peroxidation and function of mitochondria in kidney cells of diabetic rats as a model of diabetic nephropathy. CONCLUSION: In conclusion it may be suggested that new therapies based on nano-formulated calycosin can restore mitochondrial function which can improve diabetic nephropathy.
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Nefropatías Diabéticas/tratamiento farmacológico , Isoflavonas/química , Isoflavonas/farmacología , Liposomas/química , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Animales , Antioxidantes , Astragalus propinquus , Disponibilidad Biológica , Diabetes Mellitus Experimental , Liberación de Fármacos , Medicamentos Herbarios Chinos , Isoflavonas/uso terapéutico , Riñón , Peroxidación de Lípido , Masculino , Tamaño de la Partícula , Ratas , Ratas Sprague-DawleyRESUMEN
Described herein is an imidazole ring formation strategy for the synthesis of axially chiral N-arylbenzimidazoles by means of chiral phosphoric acid catalysis. Two sets of conditions were developed to transform two classes of 2-naphthylamine derivatives into structurally diverse N-arylbenzimidazole atropisomers with excellent chemo- and regioselectivity as well as high levels of enantiocontrol. It is worth reflecting on the unique roles played by the nitroso group in this domino reaction. It functions as a linchpin by first offering an electrophilic site (N) for the initial C-N bond formation while the resulting amine performs the nucleophilic addition to form the second C-N bond. Additionally, it could facilitate the final oxidative aromatization as an oxidant. The atropisomeric products could be conveniently elaborated to a series of axially chiral derivatives, enabling the exploitation of N-arylbenzimidazoles for their potential utilities in asymmetric catalysis.
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Tendon repair is a clinical challenge because of the limited understanding on tenogenesis. The synthesis of type I collagen (Collagen I) and other extracellular matrix are essential for tendon differentiation and homeostasis. Current studies on tenogenesis focused mostly on the tenogenic transcriptional factors while the signaling controlling tenogenesis on translational level remains largely unknown. Here, we showed that mechanistic target of rapamycin (mTOR) signaling was activated by protenogenic growth factor, transforming growth factors beta1, and insulin-like growth factor-I. The expression of mTOR was upregulated during tenogenesis of mesenchymal stem cells (MSCs). Moreover, mTOR was downregulated in human tendinopathy tissues and was inactivated upon statin treatment. Both inhibition and depletion of AKT or mTOR significantly reduced type I collagen production and impaired tenogenesis of MSCs. Tendon specific-ablation of mTOR resulted in tendon defect and reduction of Collagen I. However, there is no evident downregulation of tendon associated collagens at the transcription level. Our study demonstrated that AKT-mTOR axis is a key mediator of tendon differentiation and provided a novel therapeutic target for tendinopathy and tendon injuries. Stem Cells 2018;36:527-539.
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Diferenciación Celular , Células Madre Mesenquimatosas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo , Tendones/metabolismo , Animales , Células Madre Mesenquimatosas/citología , Ratones , Tendones/citología , Factor de Crecimiento Transformador beta1/metabolismoRESUMEN
A series of novel anionic e-surfactants n-C cP pS was molecular designed and synthesized from long-chain fatty alcohols by polypropoxylation and sulfation followed by neutralization. Excellent all-round performance of extended surfactants (e-surfactants) interests us how a simple polypropylene oxide (PPO) spacer has great effects on properties. By a comparative study of conventional/ethoxylated/extended n-alkylsulfate surfactants, we were surprised to find that e-surfactants are in an obvious rugby shape at the air/water surface according to molecular surface area ( am), and it comes down to the intramolecular PPO spacer coiling and surface-induced collapse. On the basis of the interfacial properties of the e-surfactants, it is found that the PPO spacer can provide both hydrophilic and lipophilic contributions to an e-surfactant molecule. The synergism between PPO spacers and alkyl chains indicates that a certain PPO spacer can adjust the contributions in view of different alkyl chain lengths. Therefore, it is both the rugby-shaped molecular geometry of e-surfactants and the dynamic amphipathicity of a PPO spacer that makes e-surfactants behave with excellent interfacial and solution properties for household cleaning. Therefore, this work gives us a hint that the molecular geometry of surfactants plays a vital role in interfacial and solution properties similar to molecular amphipathicity.
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The longhorn beetle Dorysthenes paradoxus (Faldermann, 1833) (Coleoptera: Cerambycidae) is not only a serious agricultural pest but also a traditionally edible insect in China. However, no genetic information on this species has been acquired. In the present study, we report the mitochondrial genome (mitogenome) of Do. paradoxus, as the first complete mitogenome of Prioninae. The circular mitogenome of 15,922 bp encodes 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), and two ribosomal RNAs (rRNAs), and it contains an A+T-rich region. This mitogenome exhibits the lowest A+T content (71.13%) but harbors the largest AT skew (0.116) among the completely sequenced Cerambycidae species. Eleven of the 13 PCGs have a typical ATN start codon, whereas COI and ND1 are tentatively designated by AAT and TTG, respectively. Only 4 of the 13 PCGs harbor a complete termination codon, and the remaining 9 possess incomplete termination codons (T or TA). Apart from tRNASer(AGN), the other 21 tRNAs can fold into a typical clover-leaf secondary structures. The Do. paradoxus A+T-rich region contains two poly-T stretches and a tandem repeat that comprises two 47-bp-long copies. Both Bayesian inference and Maximum likelihood analyses confirmed the subfamily ranks of Cerambycidae ([Prioninae + Cerambycinae] + Lamiinae) and the close relationship between Philinae and Prioninae/Cerambycinae. However, the data did not support the monophyly of Prioninae and Cerambycinae. The mitogenome presented here provides basic genetic information for this economically important species.
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Escarabajos/genética , Genoma de los Insectos , Genoma Mitocondrial , Animales , FilogeniaRESUMEN
Described herein is an environmentally benign method for the synthesis of multisubstituted 3-alkoxylated-2-oxindoles 3 via direct alkoxylation of 3-halooxindoles 1. A wide variety of such multisubstituted 3-alkoxylated-2-oxindole scaffolds were smoothly obtained in good yields (up to 94%) by heating in an oil bath at 35 °C for 24 h. A particularly valuable feature of this method was the development of environment-friendly chemistry using alcohols 2 as both the substrates and solvents in the presence of a catalytic amount of base.
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Alcoholes/química , Indoles/química , Solventes/química , Catálisis , Estructura Molecular , Oxindoles , EstereoisomerismoRESUMEN
The amount of sulfur dioxide residue is currently employed by Chinese Pharmacopoeia (CP) as an index to screen sulfur-fumigated herbs, but it is unclear if this index can objectively reflect the quality of sulfur-fumigated herbs. In the present study, sulfur-containing derivatives were confirmed in sulfur-fumigated Moutan Cortex (MC) by UPLC-QTOF-MS/MS analysis, and the contents of sulfur-containing derivatives and sulfur dioxide residues were statistically analyzed both in self-made and commercially available sulfur-fumigated and non-fumigated MC as well as the samples thereof before and after eight-month storage. The amount of sulfur dioxide was significantly decreased, but that of the newly-generated sulfur-containing markers was not, after eight-month storage of the sulfur-fumigated MC samples, indicating that the amount of sulfur dioxide residue may not be positively correlated with the quality of sulfur-fumigated MC. Therefore, sulfur dioxide residue index alone may not objectively reflect the sulfur-fumigation extent (quality change extent) of MC, more specific method using characteristic sulfur-containing derivatives as chemical markers should be developed to supplement the sulfur dioxide residue determination in the quality control of sulfur-fumigated MC.
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Medicamentos Herbarios Chinos/química , Fumigación , Paeonia/química , Control de Calidad , Azufre/química , Cromatografía Líquida de Alta Presión , Dióxido de Azufre , Espectrometría de Masas en TándemRESUMEN
The stability of cyclodextrin (CD)-based emulsions is attributed to the formation of a solid film of oil-CD complexes at the oil/water interface. However, competitive interactions between CDs and other components at the interface still need to be understood. Here we develop two different routes that allow the incorporation of a model protein (sodium caseinate, SC) into emulsions based on ß-CD. One route is the components adsorbed simultaneously from a mixed solution to the oil/water interface (route I), and the other is SC was added to a previously established CD-stabilized interface (route II). The adsorption mechanism of ß-CD modified by SC at the oil/water interface is investigated by rheological and optical methods. Strong sensitivity of the rheological behavior to the routes is indicated by both steady-state and small-deformation oscillatory experiments. Possible ß-CD/SC interaction models at the interface are proposed. In route I, the protein, due to its higher affinity for the interface, adsorbs strongly at the interface with blocking of the adsorption of ß-CD and formation of oil-CD complexes. In route II, the protein penetrates and blends into the preadsorbed layer of oil-CD complexes already formed at the interface. The revelation of interfacial assembly is expected to help better understand CD-based emulsions in natural systems and improve their designs in engineering applications.
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Dimethylsulfoniopropionate (DMSP) and nitric oxide (NO) in marine microalgae are considered as two important compounds involved in a variety of physiological functions. We examined the NO responses and the growth of Isochrysis galbana Parke and Gymnodinium sp. when supplemented with different concentrations of DMSP solutions in the cultures. Production of DMSP and dimethylsulfide (DMS) in Amphidinium carterae and Emiliania Huxleyi was investigated after the addition of NO donor sodium nitroprusside (SNP) and NO solution to algal media. The release peaks of NO were observed in cell suspensions of I. galbana Parke and Gymnodinium sp. immediately after the injection of DMSP solutions. The growth of these two microalgae was found to be significantly promoted or inhibited caused by exogenous DMSP. There was a decrease of DMSP concentrations in algal cultures within 24 h, accompanied with an increase in DMS, due to the effect of NO. The results provided direct evidence to confirm that there exist mutual effects of DMSP and NO during the growth of marine microalgae, which is speculated to be related to their roles as signaling molecules in planktonic communities.
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Biología Marina , Microalgas/crecimiento & desarrollo , Óxido Nítrico/farmacología , Compuestos de Sulfonio/farmacologíaRESUMEN
In the present paper, the authors use permanent scatterers synthetic aperture radar interferometry (PS-InSAR) technique and 29 acquisitions by Envisat during 2003 to 2009 to monitor and analyze the spatial-temporal distribution and mechanism characterize of land subsidence in Beijing plain area. The results show that subsidence bowls have been bounded together in Beijing plain area, which covers Chaoyang, Changping, Shunyi and Tongzhou area, and the range of subsidence has an eastward trend. The most serious regional subsidence is mainly distributed by the quaternary depression in Beijing plain area. PS-Insar results also show a new subsidence bowl in Pinggu. What's more, the spatial and temporal distribution of deformation is controlled mainly by faults, such as Liangxiang-Shunyi fault, Huangzhuang-Gaoliying fault, and Nankou-Sunhe fault. The subsidence and level of groundwater in study area shows a good correlation, and the subsidence shows seasonal ups trend during November to March and seasonal downs trend during March to June along with changes in groundwater levels. The contribution of land subsidence is also influenced by stress-strain behavior of aquitards. The compaction of aquitards shows an elastic, plastic, viscoelastic pattern.
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The content of SO2 in Paeoniae Radix Alba (RPA) was determined by the method documented in Chinese Pharmacopoeia (CP) 2010 edition to validate the repeatability of the method for evaluating RPA, and the contents of paeoniflorin sulfonate in both the residual material and distilled solution of RPA were determined by HPLC to study the transformation of paeoniflorin sulfonate to SO2 by HCl. It was found that the repeatability of the method in CP for evaluating RPA is unacceptable, and paeoniflorin sulfonate was detectable in both the residual material and distilled solution of RPA even at "the end point" of SO2 determination, merely about 50% of paeoniflorin sulfonate was transformed to SO2 by HCl, indicating that the current SO2 determination method in CP is not able to accurately quantify SO2 in RPA. It is recommended that more special method for determining SO2 content in RPA should be developed regarding the chemical characteristics of sulfur-fumigated RPA.
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Técnicas de Química Analítica/métodos , Medicamentos Herbarios Chinos/análisis , Paeonia/química , Farmacopeas como Asunto/normas , Dióxido de Azufre/química , Química Farmacéutica , Fumigación , Glucósidos/análisis , Monoterpenos/análisisRESUMEN
An ultra-performance liquid chromatography-quadrupole/time of flight mass spectrometry (UPLC-Q-TOF-MS/MS) combined with reference herb method was developed to rapidly screen commercial sulfur-fumigated ginseng. Sufur-fumigated ginseng reference herb was prepared using genuine ginseng by conventional procedure. Then the reference sulfur-fumigated ginseng sample was analyzed by UPLC-Q-TOF-MS/MS to identify characteristic marker components. 25-hydroxyl-Re sulfate with higher abundance was se- lected as marker compound from 8 characteristic components identified in sulfur-fumigated ginseng reference herb. The fragmentation of 25-hydroxyl-Re sulfate was extensively investigated, fragment ion m/z 879.44 with higher intensity was chosen as the characteristic ion of sulfur-fumigated ginseng. The response of ion m/z 879. 44 was improved by optimizing the MS conditions so that this ion could be used as the characteristic marker ion for screening purpose in ion extracting screening mode. The established approach was successfully applied to inspect 21 commercial ginseng samples collected from different cities in China It was found that the chemical profiles of 9 samples were similar to that of sulfur-fumigated ginseng reference herb, and the characteristic ion m/z 879. 44 of 25-hydroxyl-Re sulfate was also detected in these samples, suggesting that there were nearly 43% ginseng samples analyzed being sulfur-fumigated. This findng agreed well with the results of sulfur dioxide residues of these 21 commercial ginseng samples determined with the method documented in Chinese Pharmacopeia Compared with the method documented in Chinese Pharmacopeia, the proposed approach is more rapid and specific for screening sulfur-fumigated ginseng. SFDA of China should strengthen the enforcement to prohibit ginseng being sulfur-fumigated, so that ginseng and it preparations could be effectively and safely benefit to the health of human beings.