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921.
Cocaine dependence is a neuropsychiatric disorder in which both environmental and genetic factors are involved. Several processes, that include reward and neuroadaptations, mediate the transition from use to dependence. In this regard, dopamine and serotonin neurotransmission systems are clearly involved in reward and other cocaine‐related effects, whereas neurotrophic factors may be responsible for neuroadaptations associated with cocaine dependence. We examined the contribution to cocaine dependence of 37 genes related to the dopaminergic and serotoninergic systems, neurotrophic factors and their receptors through a case–control association study with 319 single nucleotide polymorphisms selected according to genetic coverage criteria in 432 cocaine‐dependent patients and 482 sex‐matched unrelated controls. Single marker analyses provided evidence for association of the serotonin receptor HTR2A with cocaine dependence [rs6561333; nominal P‐value adjusted for age = 1.9e?04, odds ratio = 1.72 (1.29–2.30)]. When patients were subdivided according to the presence or absence of psychotic symptoms, we confirmed the association between cocaine dependence and HTR2A in both subgroups of patients. Our data show additional evidence for the involvement of the serotoninergic system in the genetic susceptibility to cocaine dependence.  相似文献   
922.
The single‐nucleotide polymorphism (SNP) rs10503253, located within the CUB and Sushi multiple domains‐1 (CSMD1) gene on 8p23.2, was recently identified as genome‐wide significant for schizophrenia (SZ), but is of unknown function. We investigated the neurocognitive effects of this CSMD1 variant in vivo in patients and healthy participants using behavioral and imaging measures of brain structure and function. We compared carriers and non‐carriers of the risk ‘A’ allele on measures of neuropsychological performance typically impaired in SZ (general cognitive ability, episodic and working memory and attentional control) in independent samples of Irish patients (n = 387) and controls (n = 171) and German patients (205) and controls (n = 533). Across these groups, the risk ‘A’ allele at CSMD1 was associated with deleterious effects across a number of neurocognitive phenotypes. Specifically, the risk allele was associated with poorer performance on neuropsychological measures of general cognitive ability and memory function but not attentional control. These effects, while significant, were subtle, and varied between samples. Consistent with previous evidence suggesting that CSMD1 may be involved in brain mechanisms related to memory and learning, these data appear to reflect the deleterious effects of the identified ‘A’ risk allele on neurocognitive function, possibly as part of the mechanism by which CSMD1 is associated with SZ risk.  相似文献   
923.
924.
925.
Dalmatian pyrethrum (Tanacetum cinerariifolium (Trevir. ) Sch.Bip. ) is a plant species endemic to the east Adriatic coast. The bioactive substance of Dalmatian pyrethrum is a natural insecticide, pyrethrin, a mixture of six active components (pyrethrins I and II, cinerins I and II, and jasmolins I and II). The insecticidal potential of pyrethrin was recognized decades ago, and dried and ground flowers have traditionally been used in Croatian agriculture and households. A total of 25 Dalmatian pyrethrum populations from Croatia were studied to determine the pyrethrin content and composition, and to identify distinct chemotypes. The total pyrethrin content ranged from 0.36 to 1.30% (dry flower weight; DW) and the pyrethrin I/pyrethrin II ratio ranged from 0.64 to 3.33%. The statistical analyses revealed that the correlations between the percentage of pyrethrin I and of all the other components were significant and negative. The total pyrethrin content was positively correlated with the percentage of pyrethrin I and negatively correlated with cinerin II. The multivariate analysis of the chemical variability enabled the identification of five chemotypes among 25 Dalmatian pyrethrum populations. The chemical characterization of indigenous Dalmatian pyrethrum populations may serve as a good background for future breeding and agricultural exploitation.  相似文献   
926.
A rapid reversed‐phase (RP) high‐performance liquid chromatography method was developed and applied for simultaneous separation, and determination of flavonoids and phenolic acids in eight Plantago L. taxa (P. altissima L., P. argentea Chaix , P. coronopus L., P. holosteum Scop . ssp. depauperata Pilger , P. holosteum ssp. holosteum, P. holosteum ssp. scopulorum (Degen) Horvati? , P. lagopus L., and P. maritima L.) growing in Croatia. Chromatographic separation was carried out on Zorbax Eclipse XDB‐C18 using gradient elution with a H2O (pH 2.5, adjusted with CF3COOH) and MeCN mixture at 30°. The contents of analyzed phenolic compounds (% of the dry weight of the leaves, dw) varied among examined species: rutin (max. 0.024%, P. argentea), hyperoside (max. 0.020%, P. lagopus), quercitrin (max. 0.013%, P. holosteum ssp. holosteum), quercetin (max. 0.028%, P. holosteum ssp. scopulorum), chlorogenic acid (max. 0.115%, P. lagopus), and caffeic acid (max. 0.046%, P. coronopus). Isoquercitrin was detected only in P. argentea (0.020%), while isochlorogenic acid content was below limit of quantification in all investigated species. Multivariate analyses (UPGMA and PCA) showed significant differences in contents of investigated polyphenolic compounds between different Plantago taxa. Accordingly, investigated substances might be employed as chemotaxonomic markers in the study of the complex genus Plantago.  相似文献   
927.
An investigation on the secondary metabolites from the BuOH extract of the fermentation broth of the thermotolerant polyester‐degrading actinomycete Actinomadura miaoliensis BCRC 16873 was carried out. One previously undescribed α‐pyrone (=pyran‐2‐one) derivative, designated as miaolienone ( 1 ), and a new butanolide, miaolinolide ( 2 ), together with 13 known compounds, 3 – 15 , were obtained. Their structures were established on the basis of extensive 1D‐ and 2D‐NMR analyses in combination with HR‐MS experiments. In addition, the isolated compounds 1 – 15 were evaluated for the inhibitory effects of the isolates on the production of tumor necrosis factor (TNF‐α) induced by lipopolysaccharide (LPS). Among the isolates, 1 and 2 significantly inhibited TNF‐α production in U937 cells in vitro, and the IC50 values were 0.59 and 0.76 μM , respectively. Compounds 3 – 5 displayed moderate inhibitory activities on LPS‐induced TNF‐α production.  相似文献   
928.
Four highly acylated diterpenoids, designated as pierisformotoxins A–D ( 1 – 4 , resp.), along with 26 known compounds, were isolated from the flowers of Pieris formosa. Among them, pierisformotoxins A and B ( 1 and 2 , resp.) were new highly acylated grayanane diterpenoids, of which the five‐membered ring A has undergone an oxidative cleavage between C(3) and C(4), followed by lactonization, to give rise to a five‐membered lactone ring between C(3) and C(5), differing from the previously reported grayanane diterpenoids with a 5/7/6/5 ring system. Results of the cAMP‐regulation‐activity assay showed that pierisformotoxin C ( 3 ) at 10 μM (inhibitory ratio (IR): 10.1%) or 2 μM (9.8%), and pierisformotoxin B ( 2 ) at 50 μM (13.9%) significantly decreased the cAMP level in N1E‐115 neuroblastoma cells (p<0.05).  相似文献   
929.
After a survey of the special role, which the amino acid proline plays in the chemistry of life, the cell‐penetrating properties of polycationic proline‐containing peptides are discussed, and the widely unknown discovery by the Giralt group (J. Am. Chem. Soc. 2002 , 124, 8876) is acknowledged, according to which fluorescein‐labeled tetradecaproline is slowly taken up by rat kidney cells (NRK‐49F). Here, we describe details of our previously mentioned (Chem. Biodiversity 2004 , 1, 1111) observation that a hexa‐β3‐Pro derivative penetrates fibroblast cells, and we present the results of an extensive investigation of oligo‐L ‐ and oligo‐D ‐α‐prolines, as well as of oligo‐β2h‐ and oligo‐β3h‐prolines without and with fluorescence labels ( 1 – 8 ; Fig. 1). Permeation through protein‐free phospholipid bilayers is detected with the nanoFAST biochip technology (Figs. 24). This methodology is applied for the first time for quantitative determination of translocation rates of cell‐penetrating peptides (CPPs) across lipid bilayers. Cell penetration is observed with mouse (3T3) and human foreskin fibroblasts (HFF; Figs. 5 and 68, resp.). The stabilities of oligoprolines in heparin‐stabilized human plasma increase with decreasing chain lengths (Figs. 911). Time‐ and solvent‐dependent CD spectra of most of the oligoprolines (Figs. 13 and 14) show changes that may be interpreted as arising from aggregation, and broadening of the NMR signals with time confirms this assumption.  相似文献   
930.
Six new triterpenoids, meliasenins S–X ( 1 – 6 , resp.), were isolated from the stem bark of Melia toosendan. Their structures were elucidated by mass spectrometry, NMR experiments, and comparison with the known compounds. Particularly, the absolute configuration at C(24) in new compounds was determined through their CD spectra of the [Pr(FOD)3] complex (fod=1,1,1,2,2,3,3,7,7,7‐decafluoroheptane‐4,6‐dione) in CCl4, as well as by using Mosher's method.  相似文献   
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