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1.
The formation of multiple cysts in one or several organs is a characteristic of several human inherited diseases. Recent research suggests that problems in planar cell polarity may be the common denominator in polycystic diseases. Mutations in at least two genes are linked to autosomal dominant polycystic liver disease (PCLD), PRKCSH and SEC63. A recent study linked PRKCSH to the signaling- and cytoskeletal adaptor-component β-catenin. In a yeast two hybrid screen we identified the cytosolic protein nucleoredoxin (NRX) as an interaction partner of human Sec63. Since NRX is involved in the Wnt signaling pathways, we characterized this interaction. Thus, Sec63 is linked to the Wnt signaling pathways and this interaction may be the reason why mutations in SEC63 can lead to PCLD.

Structured summary

Sec63physically interacts with NRX by two hybrid(View interaction)NRXbinds to Sec63 by peptide array (View Interaction 1, 2)Sec63binds to NRX by pull down(View interaction)Sec63binds to NRX by peptide array (View Interaction 1, 2, 3)  相似文献   

2.
S. Mario Sousa 《Brittonia》2010,62(4):321-336
The Lonchocarpus cruentus complex, within sect. Lonchocarpus, is described. This complex is characterized by the presence of a keeled vexillary margin on the pod. Five of the six species described and illustrated are new to science: Lonchocarpus aequatorialis, L. alternifoliolatus, L. guianensis, L. septentrionalis and L. trinitensis. A pronounced flower size difference in the north-south distribution of this complex is shown.  相似文献   

3.
Streptomyces fradiae produces several extracellular proteases and many of these are inducible. An 8.8 kb DNA fragment of Streptomyces fradiae cloned on pIJ699 caused increased protease activity in Streptomyces lividans.Clones carrying this recombinant plasmid showed a significant delay in sporulation. A protein of 18 kDa was purified from the extracellular proteins secreted by the host carrying the recombinant plasmid. Further characterization showed that this protease is a metalloprotease.  相似文献   

4.
Conferin (1), a new isoflavone, has been isolated from the ethyl acetate soluble fraction of Caragana conferta Benth. along with seven known compounds, namely biochanin A (2), p-hydroxybenzoic acid (3), 3,5- dimethoxybenzoic acid (4), ursolic acid (5), erythrodiol (6), pinoresinol (7), and syringresinol (8), reported for the first time from this species. The structure of the new isoflavone was deduced on the basis of spectroscopic studies. Compounds 1 and 2 were investigated for biological activities and showed significant anti-inflammatory activity in carrageenan induced paw edema of rats. Evaluation of antioxidant activity by the radical scavenging method indicated that compound 1 is a potent antioxidant while 2 is moderately active. It was also shown that the reducing capability of compound 2 was remarkably increased in a concentration dependent manner as compared to 1. Compound 1 showed moderate inhibitory activity against the enzyme lipoxygenase, while 2 showed weak activity.  相似文献   

5.
Tyrosinase is the rate-limiting enzyme for the production of melanin and other pigments via the oxidation of l-tyrosine. The methanol extract from Humulus lupulus showed potent inhibition against mushroom tyrosinase. The bioactivity-guided fractionation of this methanol extract resulted in the isolation of seven flavonoids (17), identified as xanthohumol (1), 4′-O-methylxanthohumol (2), xanthohumol C (3), flavokawain C (4), xanthoumol B (5), 6-prenylnaringenin (6) and isoxanthohumol (7). All isolated flavonoids (17) effectively inhibited the monophenolase (IC50s?=?15.4–58.4?µM) and diphenolase (IC50s?=?27.1–117.4?µM) activities of tyrosinase. Kinetic studies using Lineweaver–Burk and Dixon-plots revealed that chalcones (15) were competitive inhibitors, whereas flavanones (6 and 7) exhibited both mixed and non-competitive inhibitory characteristics. In conclusion, this study is the first to demonstrate that the phenolic phytochemicals of H. lupulus display potent inhibitory activities against tyrosinase.  相似文献   

6.
The aim of this study was to determine the biological activity of 4 steroidal derivatives (9a, 9b and 10a, 10b) prepared from the commercially available 17α acetoxyprogesterone, where 9a, 9b, have the Δ4-3-oxo structure and 10a and 10b an epoxy group at C-4 and C-5.

These steroids were tested as inhibitors of 5α-reductase enzyme, which is present in androgen-dependent tissues and converts testosterone to its more active reduced metabolite dihydrotestosterone.

The pharmacological effect of these steroids was demonstrated by the significant decrease of the weight of the prostate gland of gonadectomized hamsters treated with testosterone plus finasteride or with steroids 10a and 10b. For the studies in vitro the IC50 values were determined by measuring the steroid concentration that inhibits 50% of the activity of-5α-reductase. In this study we also determined the capacity of these steroids to bind to the androgen receptor present in the rat prostate cytosol.

The results from this work indicated that compounds 9a, 9b, 10a, and 10b inhibited the 5α reductase activity with IC50 values of 360, 370, 13 and 4.9 nM respectively. However these steroids did not bind to the androgen receptors since none competed with labeled mibolerone. Steroid 10b, an epoxy steroidal derivative containing bromine atom in the ester moiety, was the most active inhibitor of 5α-reductase enzyme, present in human prostate homogenates with an IC50 value of 4.9 nM and also showed in vivo pharmacological activity since it decreased the weight of the prostate from hamsters treated with testosterone in a similar way as finasteride.  相似文献   

7.
Abstract

Context: Variations in the fat mass and obesity-associated gene (FTO) has been associated with obesity in many populations, but the results are conflicting.

Objective: The aim of this study was to evaluate the effect of the rs9939609 polymorphism in the FTO gene on obesity risk and plasma leptin, adiponectin, insulin and lipid concentrations in Tunisians.

Materials and methods: Four hundred and ninety-four subjects with obesity and 334 non-obese participated in this study. The rs9939609 (T/A) genotype was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.

Results: Significant differences in genotype frequencies were observed between cases and controls. In the separate analysis by gender, the association between the AA genotype and obesity was statistically significant in women but not in men. After stratification by obesity class this association remains only with obesity class III.

Discussion: Our study is in agreement with studies on Caucasian, Portuguese and Cebu Filipino populations where a gender-specific association was found between rs9939609 polymorphism and obesity. It is also in agreement with studies on Mexican, Spanish and European populations, where an association was found with obesity class III.

Conclusion: The rs9939609 polymorphism of FTO gene is associated with obesity, especially obesity class III in women.  相似文献   

8.
Growing evidence suggests that astrocytes are the active partners of neurons in many brain functions. Astrocytic mitochondria are highly motile organelles which regulate the temporal and spatial patterns of Ca 2+ dynamics, in addition to being a major source of ATP and reactive oxygen species. Previous studies have shown that mitochondria translocate to endoplasmic reticulum during Ca 2+ release from internal stores, but whether a similar spatial interaction between mitochondria and plasma membrane occurs is not known. Using total internal reflection fluorescence (TIRF) microscopy we show that a fraction of mitochondria became trapped near the plasma membrane of cultured hippocampal astrocytes during exposure to the transmitters glutamate or ATP, resulting in net translocation of the mitochondria to the plasma membrane. This translocation was dependent on the intracellular Ca 2+ rise because it was blocked by pre-incubation with BAPTA AM and mimicked by application of the Ca 2+ ionophore ionomycin. Transmembrane Ca 2+ influx induced by raising external Ca 2+ also caused mitochondrial trapping, which occurred more rapidly than that produced by glutamate or ATP. In astrocytes treated with the microtubule-disrupting agent nocodazole, intracellular Ca 2+ rises failed to induce trapping of mitochondria near plasma membrane, suggesting a role for microtubules in this phenomenon. Our data reveal the Ca 2+ -dependent trapping of mitochondria near the plasma membrane as a novel form of mitochondrial regulation, which is likely to control the perimembrane Ca 2+ dynamics and regulate signaling by mitochondria-derived reactive oxygen species. Electronic Supplementary Materials Supplementary Materials is available in the online version of this article at  相似文献   

9.
The insect antifeedant activities of pterocarpans and a sesquiterpene alcohol from the dichloromethane extract of Pterocarpus macrocarpus Kruz. (Leguminosae) were evaluated against the common cutworm, Spodoptera litura F. (Noctuidae), and the subterranean termite, Reticulitermes speratus (Kolbe)(Rhinotermitidae). Three pterocarpans, (?)-homopterocarpin (1), (?)-pterocarpin (2), and (?)-hydroxyhomopterocarpin (3) and the sesquiterpene alcohol, (+)-pterocarpol (5), were isolated from the dichloromethane extract of the heartwood of P. macrocarpus under guidance by a biological assay. Among these natural products, the most active insect antifeedant against both S. litura and R. speratus was 1. On the other hand, sesquiterpene alcohol 5 showed less insect antifeedant activity than the other pterocarpans against both insect species. While its methylated derivative, (?)-methoxyhomopterocarpin (4), showed high biological activity, 3 showed less insect antifeedant activity in this study. Interestingly, racemic 1 did not show insect antifeedant activity against S. litura. However, all of the test pterocarpans and isoflavones showed antifeedant activity against the test termites. Additionally, since these compounds were major constituents of P. macrocarpus, these antifeedant phenolics may act as chemical defense factors in this tree. In Thailand, lumber made from this tree is used to make furniture and in building construction due to its resistance to termite attack.  相似文献   

10.
ABSTRACT

The coat colour in mammals is determined by the relative amounts of eumelanin (black/brown) and phaeomelanin (red/yellow), produced in melanocytes, which are controlled by melanocyte stimulating hormone receptor (MSH-R). Melanocyte stimulating hormone receptor is activated by α-melanocyte-stimulating hormone (α-MSH). Stimulated MSH-R activates adenylyl cyclase (AC), thereby increasing the amount of cyclic AMP in the cell, which activates the enzyme tyrosinase resulting in eumelanin synthesis. In this study the complete coding sequences of five alleles of the MSH-R gene found in Holstein, Red Holstein, Simmental, and Brown Swiss cattle were cloned into a mammalian expression vector and transfected into human embryonic kidney (HEK) 293 cells. The expressed receptors were analyzed for their ability to increase intracellular cAMP in response to stimulation by α-MSH. The recessive red allele (e) found in Red Holstein and Simmental and the dominant black allele (ED) found in Holstein were unresponsive to a wide range of α-MSH concentrations. Two alleles from Brown Swiss (Ed1, Ed2) and one allele found in the Simmental breed (ef) responded to stimulation by α-MSH in a dose-dependent manner. When compared to Ed1 and Ed2, the cells transfected with the ef MSH-R allele, however, reached the corresponding intracellular cAMP concentrations at a 10-fold higher concentration of α-MSH. In conjunction with the mode of inheritance of coat colour, the results indicate that the e MSH-R allele is a non-functional receptor, ED is constitutively activated receptor, and Ed1 and Ed2 are hormonally activated receptors. The delay in ef MSH-R response may explain the similarity between the e and ef phenotypes.  相似文献   

11.
A new series of quinoline analogs have been synthesized and found active against P. falciparum in vitro and P. yoelli in vivo. Compounds 8, 10 and 11 exhibited superior in vitro activity compared to chloroquine. Selected compounds 8, 10 and 11 exhibited significant suppression of parasitaemia in vivo assay. These analogs form a complex with hematin and inhibit the β-hematin formation, suggesting that this class of compounds act on a heme polymerization target. Further this study confirms that quinoline ring nitrogen is essential for both transportation of the molecule across the membrane as well as for tight binding to hematin.  相似文献   

12.
13.
广东省县级公立医院改革试点医院效率分析   总被引:1,自引:0,他引:1  
目的 评价县级公立医院综合改革试点医院服务体系运营效率。方法 以广东省第一批县级公立医院综合改革试点医院为研究对象,运用DEA-Malmquist指数法分析其全要素生产率及其分解因素的变化趋势。结果 2012—2015年广东第一批县级公立医院改革试点医院全要素生产率平均下降1.6%,技术进步下降2.4%,技术效率增长0.8%。纯技术效率和规模效率年平均增长率分别为0.5%和0.2%;跨年度全要素生产率由0.951上,升到1.004。结论 广东省县级公立医院全要素生产率有待提高,需补足技术短板,从而提高整体运营效率。  相似文献   

14.
Abstract

A hydrolysis study of 3-methyl-cycloSal-PCVMP 2 is described. Surprisingly, phosphotriester 5 released in this study not the expected PCVMP, but cycloPCVMP.  相似文献   

15.
Our recent molecular phylogenetic study revealed a previously unrecognized clade of six species that is sister to Elaphoglossum. Within this clade, four species are currently classified in Bolbitis, one in Lomagramma, and one in Acrostichum. For this clade, we propose the name Mickelia, with M. nicotianifolia as the type species. We also make new combinations for the species in our phylogenetic study shown to belong to Mickelia (M. bernoullii, M. guianensis, M. hemiotis, M. nicotianifolia, M. oligarchica, and M. scandens) and two other species believed to belong to the clade based on morphology (M. lindigii, M. pergamentacea). A new hybrid and two new species are also described (M. ×atrans, M. furcata, and M. pradoi). In total, Mickelia consists of ten species and one hybrid. It is entirely neotropical. We provide a key to the genera of bolbitidoid ferns and a synopsis of Mickelia that gives for each species a complete synonymy, geographical distribution, comparative discussion, and illustration.  相似文献   

16.
New acylated anthocyanins from purple yam and their antioxidant activity   总被引:2,自引:0,他引:2  
Purple yam (Dioscorea alata L.), which is widely distributed in tropical and subtropical regions, is characterized by its color and viscosity. Previous studies have shown that purple yams contain a variety of acylated anthocyanins that exhibit higher levels of antioxidant activity than the corresponding nonacylated compounds. In this study, the pigments found in purple yams from the Philippines (D. alata) were isolated and evaluated in terms of antioxidant activity. Four new acylated anthocyanins, alanins (14) were isolated from the MeOH extracts of purple yam, which were subsequently determined to be cyanidin (1, 2, and 4) and peonidin (3) type compounds, along with four known anthocyanins (58). The structures of 14 were determined by spectroscopic methods, including NMR and MS analyses. The antioxidant activities of anthocyanins 18 were investigated using oxygen radical absorbing capacity and ferric reducing antioxidant power assays.  相似文献   

17.
The interaction of a number of small organic molecules with the two lowest energy minimum conformations of [2.2.2.2]paracyclophane (4°-PCP), 1 and 2, are studied by MMP2(87) force field calculations. Formations of nesting as well as inclusion complexes were identified on the potential energy surface. With CH2Cl2 and CHCl3 used as guests, the nesting complexes are lower in energy than the inclusion ones with both conformations 1 and 2. Furthermore, the nesting complexes with 2 are found to be more stable than the nesting ones with 1. Formation of the double nesting complexes of CH2Cl2 and CHCl3 with 1 and 2 raise the difference in complexation energy in favour of 2. The preference of 4°-PCP for the form 2 in solution is explained based on the above analysis, although 2 is calculated to be 0.2 kcal·mol–1 higher in steric energy than 1 in the gas phase.Supplementary material to this paper is available in electronic form at http://dx.doi.org/10.1007/s0089490050218  相似文献   

18.
Ssanghwa-tang is a medicinal formula that is widely prescribed in Korea to decrease fatigue after an illness. Fermented herbal medicines might be made more efficacious than conventional herbal medicines by increasing the absorption and bioavailability of the active compounds. In this study, Ssanghwa-tang was fermented to produce bioconversion compositions using Lactobacillus fermentum, and six peaks were decreased, four peaks were increased and one peak newly appeared in the HPLC-DAD chromatogram. The structures of the newly-appearing compound (1) and increased (2–5) compounds were identified as follows using NMR and MS: liquiritigenin (1), nodakenetin (2), cinnamyl alcohol (3), decursinol (4), and benzoic acid (5). The decreased compounds were identified to be paeoniflorin (6), liquiritin (7), nodakenin (8), cinnamaldehyde (9), decursin (10), and decursinol angelate (11) using HPLC-DAD analysis with authentic compounds. The high performance liquid chromatography method was used to quantify the eleven constituents in Ssanghwa-tang and fermented Ssanghwa-tang. All calibration curves of the standard compounds exhibited excellent linearity with a R2 > 0.9940.  相似文献   

19.
Abstract

Objectives: Ischemic stroke is the main neurological cause of acquired incapability in adults and a prominent cause of mortality. Several association studies have been conducted to explore the role of candidate genes in this neurological condition.

Methods: In the present study, we aimed at identification of association between Glutamate Metabotropic Receptor 7 (GRM7) and risk of ischemic stroke in Iranian population. Two intronic variants within this gene (rs6782011 and rs779867) were genotyped in 318 sporadic ischemic stroke cases and 300 unrelated, healthy controls individuals.

Results: No significant difference was found in allele, genotype or haplotype frequencies of these SNPs between cases and controls after correction for multiple comparisons.

Conclusion: Consequently, the assessed GRM7 variants are not implicated in risk of ischemic stroke in Iranian population.  相似文献   

20.
Background and AimsCrassulacean acid metabolism (CAM) is an adaptation to increase water use efficiency in dry environments. Similar biochemical patterns occur in the aquatic lycophyte genus Isoëtes. It has long been assumed and accepted that CAM-like behaviour in these aquatic plants is an adaptation to low daytime carbon levels in aquatic ecosystems, but this has never been directly tested.MethodsTo test this hypothesis, populations of Isoëtes engelmannii and I. tuckermanii were grown in climate-controlled chambers and starved of atmospheric CO2 during the day while pH was measured for 24 h.Key ResultsWe demonstrate that terrestrial plants exposed to low atmospheric CO2 display diel acidity cycles similar to those in both xerophytic CAM plants and submerged Isoëtes.ConclusionsDaytime CO2 starvation induces CAM-like nocturnal acid accumulation in terrestrial Isoëtes, substantiating the hypothesis that carbon starvation is a selective pressure for this physiological behaviour.  相似文献   

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