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1.
Science ; 380(6648): eabl8621, 2023 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-37262163

RESUMEN

The biological mechanisms that underpin primate social evolution remain poorly understood. Asian colobines display a range of social organizations, which makes them good models for investigating social evolution. By integrating ecological, geological, fossil, behavioral, and genomic analyses, we found that colobine primates that inhabit colder environments tend to live in larger, more complex groups. Specifically, glacial periods during the past 6 million years promoted the selection of genes involved in cold-related energy metabolism and neurohormonal regulation. More-efficient dopamine and oxytocin pathways developed in odd-nosed monkeys, which may have favored the prolongation of maternal care and lactation, increasing infant survival in cold environments. These adaptive changes appear to have strengthened interindividual affiliation, increased male-male tolerance, and facilitated the stepwise aggregation from independent one-male groups to large multilevel societies.


Asunto(s)
Aclimatación , Clima Frío , Evolución Molecular , Presbytini , Evolución Social , Animales , Femenino , Masculino , Aclimatación/genética , Filogenia , Presbytini/genética , Presbytini/fisiología , Presbytini/psicología
2.
Molecules ; 28(3)2023 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-36770966

RESUMEN

Curcumin (Cur), a natural hydrophobic polyphenolic compound, exhibits multiple beneficial biological activities. However, low water solubility and relative instability hinder its application in food fields. In this study, carrier-free curcumin nanoparticles (CFC NPs) were prepared by adding the DMSO solution of Cur into DI water under continuous rapid stirring. The morphology of CFC NPs was a spherical shape with a diameter of 65.25 ± 2.09 nm (PDI = 0.229 ± 0.107), and the loading capacity (LC) of CFC NPs was as high as 96.68 ± 0.03%. The thermal property and crystallinity of CFC NPs were investigated by XRD. Furthermore, the CFC NPs significantly accelerated the release of Cur in vitro owing to its improved water dispersibility. Importantly, CFC NPs displayed significantly improved DPPH radical scavenging activity. Overall, all these results suggested that CFC NPs would be a promising vehicle to widen the applications of Cur in food fields.


Asunto(s)
Curcumina , Nanopartículas , Curcumina/farmacología , Curcumina/química , Antioxidantes/farmacología , Portadores de Fármacos/química , Solubilidad , Nanopartículas/química , Tamaño de la Partícula
3.
Environ Res ; 220: 115211, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36603657

RESUMEN

The Pacific Ocean plays an important role in regulating the budget of climatically active gases and the burden of sulfate aerosols. Here, a field investigation was conducted to clarify the key processes and factors controlling climatically active gases, including dimethyl sulfide (DMS), carbonyl sulfide (OCS), carbon disulfide (CS2), and carbon dioxide (CO2), in both surface seawater and the lower atmosphere of the western Pacific. In addition, the relative contributions of different sources to atmospheric sulfate aerosols were quantitatively estimated, and their causes were explored. The maximum concentrations of DMS, OCS and CS2 and the minimum partial pressure of CO2 (pCO2) were observed in the Kuroshio-Oyashio Extension. Kuroshio-induced mesoscale eddies brought abundant nutrients and organic matter from the subsurface layer of Oyashio into the euphotic layer, thus enhancing primary productivity and accelerating the photoreaction of organic matter. These processes led to higher concentrations of DMS, OCS and CS2 and lower pCO2. However, the oligotrophic subsurface layer in the subtropical gyre and the strong barrier layer in the equatorial waters suppressed the upward fluxes of nutrients and organic matter, resulting in lower surface concentrations of DMS, OCS, and CS2 in these areas. Being far from the continents, atmospheric concentrations of DMS, OCS and CS2 and pCO2 in the western Pacific generally were observed to depend on the local sea-to-air exchange and may be regulated by atmospheric oxidation and mixing of air masses. In general, oceanic DMS emissions played an important role in the formation of sulfate aerosols in the western Pacific (accounting for ∼19.5% of total sulfate aerosols), especially in the Kuroshio-Oyashio Extension (∼32.3%). These processes in seawater may also determine the variations and emissions of other climatically active gases from biogenic and photochemical sources.


Asunto(s)
Dióxido de Carbono , Gases , Sulfatos , Océano Pacífico , Aerosoles
4.
Int J Biol Macromol ; 234: 123432, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-36716835

RESUMEN

Immunostimulatory CpG oligodeoxynucleotides (CpG ODNs) show strong potential in cancer immunotherapy. However, therapeutic efficacy of CpG ODNs is hindered due to rapid nuclease degradation and insufficient cellular uptake. Transfecting CpG ODNs into antigen presenting cells (APCs) is vital to enhance their therapeutic efficacy while reduce the potential side effects. Herein, a multifunctional CpG ODNs vector was fabricated through functionalization of graphene oxide (GO) with yeast ß-D-glucan, and its potential in cancer immunotherapy was further investigated. GO-ß-D-glucan protected CpG ODNs from nuclease digestion. ß-D-glucan endowed the delivery system with targeting ability for macrophage due to its recognition with dectin-1. Thus, GO-ß-D-glucan enhanced the delivery of CpG ODNs into RAW264.7 cells due to dectin-1-mediated endocytosis. More importantly, ß-D-glucan functioned synergistically with CpG ODNs in inducing antitumor immunity. GO-ß-D-glucan/CpG ODNs inhibited the tumor cells growth more effectively. This work provides a macrophage-targeted CpG ODNs delivery system for cancer immunotherapy. Graphic abstract.


Asunto(s)
Adyuvantes Inmunológicos , Neoplasias , Humanos , Adyuvantes Inmunológicos/farmacología , Saccharomyces cerevisiae , Glucanos/farmacología , Macrófagos , Oligodesoxirribonucleótidos/farmacología
5.
Sci Total Environ ; 860: 160496, 2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36436631

RESUMEN

Perfluorinated compounds (PFCs) are useful man-made chemicals and serve as new emerging organic pollutants due to their environmental and health concerns. Chromatography-mass detection methods often need complex procedure and are also too expensive, so there is a critical demand to develop rapid, inexpensive, easy-to-operate and sensitive methods for PFCs detection. In this work, double fluorescent biosensors ('DT sensor' and 'FT sensor') have been designed to quantitatively detect long-chain perfluorinated compounds (PFCs), due to their strong hydrophobic interaction with DNA probe or lysozyme fiber. The ratio and rapid fluorescence responses offered more obvious signal changes, and high sensitivity with a limit of detection (LOD) of 0.16 µM (98.2 ppb) for perfluorododecanoic acid (PFDoA). For three PFCs with longer perfluoroalkyl chain (CF2), increased detection sensitivity was achieved due to a stronger hydrophobicity. The fluorescent biosensors showed a good selectivity for long-chain PFCs and served as cross-reactive sensors to differentiate three different long-chain PFCs. The biosensors also had robust signal response in tap water or serum samples, and the LOD can be further lowered to pM (ppt) level after sample preconcentration.


Asunto(s)
Técnicas Biosensibles , Monitoreo del Ambiente , Contaminantes Ambientales , Fluorocarburos , Humanos , Sondas de ADN , Contaminantes Ambientales/análisis , Fluorocarburos/análisis , Límite de Detección , Muramidasa/química , Contaminantes Químicos del Agua/análisis , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Monitoreo del Ambiente/instrumentación
6.
Integr Zool ; 18(3): 493-505, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36049759

RESUMEN

Understanding how natural selection shapes unique traits in mammals is a central topic in evolutionary biology. The mammalian order Chiroptera (bats) is attractive for biologists as well as the general public due to their specific traits of extraordinary immunity and inverted resting posture. However, genomic resources for bats that occupy key phylogenetic positions are not sufficient, which hinders comprehensive investigation of the molecular mechanisms underpinning the origin of specific traits in bats. Here, we sequenced the transcriptomes of 5 bats that are phylogenetically divergent and occupy key positions in the phylogenetic tree of bats. In combination with the available genomes of 19 bats and 21 other mammals, we built a database consisting of 10 918 one-to-one ortholog genes and reconstructed phylogenetic relationships of these mammals. We found that genes related to immunity, bone remodeling, and cardiovascular system are targets of natural selection along the ancestral branch of bats. Further analyses revealed that the T cell receptor signaling pathway involved in immune adaptation is specifically enriched in bats. Moreover, molecular adaptations of bone remodeling, cardiovascular system, and balance sensing may help to explain the reverted resting posture in bats. Our study provides valuable transcriptome resources, enabling us to tentatively identify genetic changes associated with bat-specific traits. This work is among the first to advance our understanding of the molecular underpinnings of inverted resting posture in bats, which could provide insight into healthcare applications such as hypertension in humans.


Asunto(s)
Quirópteros , Humanos , Animales , Quirópteros/genética , Transcriptoma , Filogenia , Mamíferos/genética , Perfilación de la Expresión Génica , Postura , Evolución Molecular
8.
Curr Zool ; 66(2): 113-122, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32211037

RESUMEN

In the face of ongoing habitat fragmentation, many primate species have experienced reduced gene flow resulting in a reduction of genetic diversity, population bottlenecks, and inbreeding depression, including golden snub-nosed monkeys Rhinopithecus roxellana. Golden snub-nosed monkeys live in a multilevel society composed of several 1 male harem units that aggregate to form a cohesive breeding band, which is followed by one or more bachelor groups composed of juvenile, subadult, and adult male members. In this research, we examine the continuous landscape resistance surface, the genetic diversity and patterns of gene flow among 4 isolated breeding bands and 1 all-male band in the Qinling Mountains, China. Landscape surface modeling suggested that human activities and ecological factors severely limit the movement of individuals among breeding bands. Although these conditions are expected to result in reduced gene flow, reduced genetic diversity, and an increased opportunity for a genetic bottleneck, based on population genetic analyses of 13 microsatellite loci from 188 individuals inhabiting 4 isolated breeding bands and 1 all-male band, we found high levels of genetic diversity but low levels of genetic divergence, as well as high rates of gene flow between males residing in the all-male band and each of the 4 breeding bands. Our results indicate that the movement of bachelor males across the landscape, along with their association with several different breeding bands, appears to provide a mechanism for promoting gene flows and maintaining genetic diversity that may counteract the otherwise isolating effects of habitat fragmentation.

9.
Gigascience ; 8(8)2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31437279

RESUMEN

BACKGROUND: The golden snub-nosed monkey (Rhinopithecus roxellana) is an endangered colobine species endemic to China, which has several distinct traits including a unique social structure. Although a genome assembly for R. roxellana is available, it is incomplete and fragmented because it was constructed using short-read sequencing technology. Thus, important information such as genome structural variation and repeat sequences may be absent. FINDINGS: To obtain a high-quality chromosomal assembly for R. roxellana qinlingensis, we used 5 methods: Pacific Bioscience single-molecule real-time sequencing, Illumina paired-end sequencing, BioNano optical maps, 10X Genomics link-reads, and high-throughput chromosome conformation capture. The assembled genome was ∼3.04 Gb, with a contig N50 of 5.72 Mb and a scaffold N50 of 144.56 Mb. This represented a 100-fold improvement over the previously published genome. In the new genome, 22,497 protein-coding genes were predicted, of which 22,053 were functionally annotated. Gene family analysis showed that 993 and 2,745 gene families were expanded and contracted, respectively. The reconstructed phylogeny recovered a close relationship between R. rollexana and Macaca mulatta, and these 2 species diverged ∼13.4 million years ago. CONCLUSION: We constructed a high-quality genome assembly of the Qinling golden snub-nosed monkey; it had superior continuity and accuracy, which might be useful for future genetic studies in this species and as a new standard reference genome for colobine primates. In addition, the updated genome assembly might improve our understanding of this species and could assist conservation efforts.


Asunto(s)
Especies en Peligro de Extinción , Genoma , Genómica , Presbytini/genética , Animales , Biología Computacional/métodos , Ontología de Genes , Genómica/métodos , Anotación de Secuencia Molecular , Filogenia , Presbytini/clasificación
10.
Proc Biol Sci ; 285(1885)2018 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-30158315

RESUMEN

Detection of evolutionary shifts in sensory systems is challenging. By adopting a molecular approach, our earlier study proposed a sensory trade-off hypothesis between a loss of colour vision and an origin of high-duty-cycle (HDC) echolocation in Old World bats. Here, we test the hypothesis in New World bats, which include HDC echolocators that are distantly related to Old World HDC echolocators, as well as vampire bats, which have an infrared sensory system apparently unique among bats. Through sequencing the short-wavelength opsin gene (SWS1) in 16 species (29 individuals) of New World bats, we identified a novel SWS1 polymorphism in an HDC echolocator: one allele is pseudogenized but the other is intact, while both alleles are either intact or pseudogenized in other individuals. Strikingly, both alleles were found to be pseudogenized in all three vampire bats. Since pseudogenization, transcriptional or translational changes could separately result in functional loss of a gene, a pseudogenized SWS1 indicates a loss of dichromatic colour vision in bats. Thus, the same sensory trade-off appears to have repeatedly occurred in the two divergent lineages of HDC echolocators, and colour vision may have also been traded off against the infrared sense in vampire bats.


Asunto(s)
Evolución Biológica , Quirópteros/fisiología , Ecolocación , Polimorfismo Genético , Opsinas de Bastones/genética , Américas , Animales , Quirópteros/genética , Filogenia , Opsinas de Bastones/metabolismo , Análisis de Secuencia de ADN/veterinaria
11.
Appl Plant Sci ; 5(7)2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28791205

RESUMEN

PREMISE OF THE STUDY: Microsatellite or simple sequence repeat (SSR) markers were developed to investigate the influence of ecological factors on gene flow and spatial genetic structuring of the submerged plant Ranunculus bungei (Ranunculaceae), which is regarded as an important species for understanding how plants adapt to an aquatic environment. METHODS AND RESULTS: Twenty-two microsatellite loci were identified from an expressed sequence tag (EST) library. The number of alleles per locus ranged from one to five, and the expected heterozygosity varied from 0.0 to 0.5 in four Chinese populations of R. bungei. Fourteen loci were polymorphic and significantly deviated from Hardy-Weinberg equilibrium. All of the loci were found to be amplifiable in two other species of Ranunculus section Batrachium, and cross-amplification in six riparian and aquatic species of Ranunculaceae was also partially successful. CONCLUSIONS: These novel EST-SSR markers will be useful for ecological and evolutionary studies of R. bungei as well as related species.

12.
BMC Genomics ; 18(1): 119, 2017 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-28143394

RESUMEN

BACKGROUND: Waterlogging or flooding is one of the most challenging abiotic stresses experienced by plants. Unlike many flooding-tolerant plants, floating-leaved aquatic plants respond actively to flooding stress by fast growth and elongation of its petioles to make leaves re-floating. However, the molecular mechanisms of this plant group responding to flood have not been investigated before. Here, we investigated the genetic basis of this adaptive response by characterizing the petiole transcriptomes of a floating-leaved species Nymphoides peltata under normal and flooding conditions. RESULTS: Clean reads under normal and flooding conditions with pooled sampling strategy were assembled into 124,302 unigenes. A total of 8883 unigenes were revealed to be differentially expressed between normal and flooding conditions. Among them, top ranked differentially expressed genes were mainly involved in antioxidant process, photosynthesis process and carbohydrate metabolism, including the glycolysis and a modified tricarboxylic acid cycle - alanine metabolism. Eight selected unigenes with significantly differentiated expression changes between normal and flooding conditions were validated by qRT-PCR. CONCLUSIONS: Among these processes, antioxidant process and glycolysis are commonly induced by waterlogging or flooding environment in plants, whereas photosynthesis and alanine metabolism are rarely occurred in other flooding-tolerant plants, suggesting the significant contributions of the two processes in the active response of N. peltata to flooding stress. Our results provide a valuable genomic resource for future studies on N. peltata and deepen our understanding of the genetic basis underlying the response to flooding stress in aquatic plants.


Asunto(s)
Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Hojas de la Planta/genética , Estrés Fisiológico/genética , Tracheophyta/genética , Transcriptoma , Adaptación Biológica/genética , Biología Computacional/métodos , Inundaciones , Ontología de Genes , Secuenciación de Nucleótidos de Alto Rendimiento , Anotación de Secuencia Molecular , Reproducibilidad de los Resultados
13.
Water Res ; 78: 1-8, 2015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25898247

RESUMEN

Sulfate radicals ( [Formula: see text] ) are applied to degrade various organic pollutants. Due to its high oxidative potential, [Formula: see text] is presumed to be able to transform bromide to reactive bromine species that can react with natural organic matter subsequently to form brominated products including brominated disinfection by-products (Br-DBPs). This research was designed to investigate the transformation of bromide in thermo activated persulfate oxidation process in the presence of humic acid (HA). Significant formation of bromoform and bromoacetic acids was verified. Their formation was attributed to the reactions of HA and reactive bromine species including Br·, [Formula: see text] HOBr(-), and free bromine resulted from the oxidation of bromide by [Formula: see text] . Yields of Br-DBPs increased monotonically at persulfate concentration of 1.0 mM and working temperature of 70 °C. However, the time-depended formation exhibited an increasing and the decreasing profile when persulfate was 5.0 mM, suggesting further degradation of organic bromine. HPLC/ICP-MS analysis demonstrated that the organic bromine was eventually transformed to bromate at this condition. Thus, a transformation scheme was proposed in which the bromine could be recycled multiple times between inorganic bromide and organic bromine before being finally transformed to bromate. This is the first study that reveals the comprehensive transformation map of bromine in [Formula: see text] based reaction systems, which should be taken into consideration when such technologies are used to eliminate contamination in real practice.


Asunto(s)
Bromuros/química , Sulfatos/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Acetatos/química , Desinfección/métodos , Halogenación , Sustancias Húmicas , Oxidación-Reducción , Trihalometanos/química
14.
Am J Bot ; 102(2): 239-47, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25667077

RESUMEN

PREMISE OF THE STUDY: Comparative phylogeography of intercontinental disjunct taxa allowed us not only to elucidate their diversification and evolution following geographic isolation, but also to understand the effect of climatic and geological histories on the evolutionary processes of closely related species. A phylogeographic analysis was conducted on the eastern Asian-North American disjunct genus Zizania to compare intracontinental phylogeographic patterns between different continents. METHODS: Surveys were conducted of 514 individuals using three chloroplast DNA fragments and three nuclear microsatellite loci. These individuals included 246 from 45 populations of Zizania latifolia in eastern Asia, and the following from North America: 154 individuals from 26 populations of Z. aquatica, 84 individuals from 14 populations of Z. palustris, and 30 individuals from one population of Z. texana. KEY RESULTS: The genetic diversity of North American Zizania was significantly higher than that of eastern Asian Zizania. High levels of genetic differentiation among populations and no signal of population expansion were detected in three widespread species. No phylogeographic structure was observed in Z. latifolia, and discordant patterns of cpDNA and microsatellite markers were observed in North American Zizania. CONCLUSIONS: Reduced variation in Zizania latifolia likely reflects its perennial life history, the North American origin of Zizania, and the relative homogeneity of aquatic environments. High levels of genetic differentiation suggest limited dispersal among populations in all Zizania species. The more complex patterns of diversification and evolution in North American Zizania may be driven by the greater impact of glaciation in North America relative to eastern Asia.


Asunto(s)
ADN de Plantas/análisis , Evolución Molecular , Variación Genética , Oryza/genética , Filogenia , Filogeografía , Poaceae/genética , ADN de Cloroplastos/análisis , Asia Oriental , Geografía , Repeticiones de Microsatélite , América del Norte , Análisis de Secuencia de ADN , Especificidad de la Especie
15.
Neural Regen Res ; 9(17): 1616-20, 2014 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-25368649

RESUMEN

Previous studies have found that methylmercury can damage hippocampal neurons and accordingly cause cognitive dysfunction. However, a non-invasive, safe and accurate detection method for detecting hippocampal injury has yet to be developed. This study aimed to detect methylmercury-induced damage on hippocampal tissue using proton magnetic resonance spectroscopy. Rats were given a subcutaneous injection of 4 and 2 mg/kg methylmercury into the neck for 50 consecutive days. Water maze and pathology tests confirmed that cognitive function had been impaired and that the ultrastructure of hippocampal tissue was altered after injection. The results of proton magnetic resonance spectroscopy revealed that the nitrogen-acetyl aspartate/creatine, choline complex/creatine and myoinositol/creatine ratio in rat hippocampal tissue were unchanged. Therefore, proton magnetic resonance spectroscopy can not be used to determine structural damage in the adult rat hippocampus caused by methylmercury chloride.

16.
Molecules ; 19(5): 6822-37, 2014 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-24858269

RESUMEN

A series of amino acid and dipeptide prodrugs of IMB-070593, a fluoroquinolone candidate discovered in our lab, were synthesized and evaluated for their water solubility and then antibacterial activity. Our results reveal that four amino acid prodrugs 4a,b,e,f and two dipeptide prodrugs 4k,l have much greater solubility (>85 mg/mL) than IMB-070593 mesylate (22.5 mg/mL). Compounds 4a and 4k show good in vivo efficacy against MSSA 12-1 (p.o./i.v., 5.32-7.68 mg/kg) and S. pneumoniae12-10 (p.o., 18.39-23.13 mg/kg) which is 1.19-1.50 fold more active than the parent drug.


Asunto(s)
Antibacterianos/farmacología , Dipéptidos/química , Dipéptidos/farmacología , Oximas/química , Piperidinas/química , Profármacos/química , Animales , Antibacterianos/administración & dosificación , Antibacterianos/química , Técnicas de Química Sintética , Inyecciones Intravenosas , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Ratones , Pruebas de Sensibilidad Microbiana , Profármacos/síntesis química , Profármacos/farmacología , Solubilidad
17.
Bioorg Med Chem Lett ; 23(6): 1754-9, 2013 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-23402878

RESUMEN

We report herein the synthesis of a series of 7-[3-alkoxyimino-4-(methyl)aminopiperidin-1-yl]quinolone/naphthyridone derivatives. In vitro antibacterial activity of these derivatives was evaluated against representative strains, and compared with ciprofloxacin (CPFX), levofloxacin (LVFX) and gemifloxacin (GMFX). The results reveal that all of the target compounds 19a-c and 20 have considerable Gram-positive activity, although they are generally less active than the reference drugs against the Gram-negative strains with some exceptions. Especially, novel compounds 19a2, 19a4 and 19a5 were found to show strong antibacterial activity (MICs: <0.008-0.5µg/mL) against all of the tested 15 Gram-positive strains including MRSA, LVFX- and GMFX-resistant MRSE, and CPFX-, LVFX- and GMFX-resistant MSSA.


Asunto(s)
Antibacterianos/síntesis química , Piperidinas/química , Quinolonas/química , Antibacterianos/química , Antibacterianos/farmacología , Farmacorresistencia Bacteriana/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Quinolonas/síntesis química , Quinolonas/farmacología , Relación Estructura-Actividad
18.
ChemMedChem ; 7(7): 1230-6, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22639240

RESUMEN

A series of novel (R)/(S)-7-(3-alkoxyimino-2-aminomethyl-1-azetidinyl)fluoroquinolone derivatives were synthesized and evaluated for their in vitro antibacterial activity against representative strains. Our results reveal that 12 of the target compounds generally show better activity (MIC: <0.008-0.5 µg mL(-1)) against the tested Gram-positive strains including MRSA and MRSE than levofloxacin (LVFX, MIC: 0.125-8 µg mL(-1)). Their activity is similar to that of gemifloxacin (GMFX, MIC: <0.008-4 µg mL(-1)). However, they are generally less active than the two reference drugs against Gram-negative strains. Moreover, against clinical strains of S. aureus including MRSA and S. epidermidis including MRSE, the MIC(50) values (0.06-16 µg mL(-1)) and MIC(90) values (0.5-32 µg mL(-1)) of compounds 16 w, y, and z are 2-8- and 2-16-fold less than LVFX, respectively, and 16 w (MIC(90) range: 0.5-4 µg mL(-1)) was also found to be more active than GMFX (MIC(90) range: 1-8 µg mL(-1)).


Asunto(s)
Antibacterianos/farmacología , Azetidinas/química , Diseño de Fármacos , Fluoroquinolonas/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Antibacterianos/síntesis química , Antibacterianos/química , Relación Dosis-Respuesta a Droga , Fluoroquinolonas/síntesis química , Fluoroquinolonas/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Estereoisomerismo , Relación Estructura-Actividad
19.
J Cell Biochem ; 113(4): 1152-8, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22275065

RESUMEN

Chronic exposure to elevated concentration of free fatty acids (FFA) has been verified to induce endoplasmic reticulum (ER) stress, which leads to pancreatic ß-cell apoptosis. As one of the medium and long chain FFA receptors, GPR40 is highly expressed in pancreatic ß cells, mediates both acute and chronic effects of FFA on ß-cell function, but the role of GPR40 in FFA-induced ß-cell apoptosis remains unclear. In this study, we investigated the possible effects of GPR40 in palmitate-induced MIN6 ß-cell apoptosis, and found that DC260126, a novel small molecular antagonist of GPR40, could protect MIN6 ß cells from palmitate-induced ER stress and apoptosis. Similar results were observed in GPR40-deficient MIN6 cells, indicating that palmitate-induced ß-cell apoptosis is at least partially dependent on ER stress pathway via GRP40.


Asunto(s)
Apoptosis/efectos de los fármacos , Retículo Endoplásmico/efectos de los fármacos , Islotes Pancreáticos/efectos de los fármacos , Ácido Palmítico/farmacología , Receptores Acoplados a Proteínas G/antagonistas & inhibidores , Animales , Secuencia de Bases , Western Blotting , Línea Celular , Cartilla de ADN , Regulación hacia Abajo , Retículo Endoplásmico/metabolismo , Islotes Pancreáticos/citología , Islotes Pancreáticos/metabolismo , Ratones , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores Acoplados a Proteínas G/metabolismo , Sulfonamidas/farmacología
20.
J Nat Prod ; 75(1): 82-7, 2012 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-22165973

RESUMEN

Two novel 2-arylbenzofuran dimers, morusyunnansins A and B (1 and 2), two new biflavonoids, morusyunnansins C and D (3 and 4), two new flavans, morusyunnansins E and F (5 and 6), and four known flavans (7-10) were isolated from the leaves of Morus yunnanensis. Compounds 5-8 showed potent inhibitory effects on mushroom tyrosinase with IC(50) values ranging from 0.12 ± 0.02 to 1.43 ± 0.43 µM.


Asunto(s)
Benzofuranos/aislamiento & purificación , Biflavonoides/aislamiento & purificación , Medicamentos Herbarios Chinos/aislamiento & purificación , Flavonoides/aislamiento & purificación , Monofenol Monooxigenasa/antagonistas & inhibidores , Morus/química , Agaricales/enzimología , Benzofuranos/química , Benzofuranos/farmacología , Biflavonoides/química , Biflavonoides/farmacología , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Flavonoides/química , Flavonoides/farmacología , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Hojas de la Planta/química , Relación Estructura-Actividad
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