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81.
Association mapping aimed at identifying DNA polymorphisms that contribute to variation in complex traits entails genotyping a large number of single-nucleotide polymorphisms (SNPs) in a very large panel of individuals. Few technologies, however, provide inexpensive high-throughput genotyping. Here, we present an efficient approach developed specifically for genotyping large fixed panels of diploid individuals. The cost-effective, open-source nature of our methodology may make it particularly attractive to those working in nonmodel systems. 相似文献
82.
Pavlov I Lauri S Taira T Rauvala H 《Birth defects research. Part C, Embryo today : reviews》2004,72(1):12-24
Growth and guidance of neurites (axons and dendrites) during development is the prerequisite for the establishment of functional neural networks in the adult organism. In the adult, mechanisms similar to those used during development may regulate plastic changes that underlie important nervous system functions, such as memory and learning. There is now ever-increasing evidence that extracellular matrix (ECM)-associated factors are critically involved in the formation of neuronal connections during development, and their plastic changes in the adult. Here, we review the current literature on the role of ECM components in activity-dependent synaptic development and plasticity, with the major focus on the thrombospondin type I repeat (TSR) domain-containing proteins. We propose that ECM components may modulate neuronal development and plasticity by: 1) regulating cellular motility and morphology, thus contributing to structural alterations that are associated with the expression of synaptic plasticity, 2) coordinating transsynaptic signaling during plasticity via their cell surface receptors, and 3) defining the physical parameters of the extracellular space, thereby regulating diffusion of soluble signaling molecules in the extracellular space (ECS). 相似文献
83.
Mannila J Lehtonen M Järvinen T Jarho P 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2004,810(2):283-290
The purpose of the study was to develop a gas chromatography-mass spectrometric (GC-MS) method for the identification and quantitation of Delta(9)-tetrahydrocannabinol (THC) in rabbit plasma. Two ionization techniques were utilized for GC-MS: electron impact ionization (EI) after i.v. administration and negative chemical ionization (NCI) after sublingual administration. THC was isolated from plasma by solid phase extraction and derivatized by either trimethylsilylation (EI) or trifuoroacetylation (NCI), with deuterated THC as an internal standard. The validity of analytical method was confirmed by investigating selectivity, limit of quantitation, linearity, accuracy, precision, recovery and stability of the analyte. The method proved to be selective, linear, accurate and precise over a range of 10-430 and 0.3-530 ng/ml of THC in plasma for EI and NCI, respectively. The extraction recovery was >81% for each concentration level studied, and the analyte was shown to be stable during storage and sample preparation. The method was applied successfully in analysing THC from rabbit plasma. 相似文献
84.
Krsmanovic LZ Mores N Navarro CE Tomić M Catt KJ 《Molecular endocrinology (Baltimore, Md.)》2001,15(3):429-440
In immortalized GnRH neurons, cAMP production is elevated by increased extracellular Ca2+ and the Ca2+ channel agonist, BK-8644, and is diminished by low extracellular Ca2+ and treatment with nifedipine, consistent with the expression of adenylyl cyclase type I (AC I). Potassium-induced depolarization of GT1-7 neurons causes a dose-dependent monotonic increase in [Ca2+]i and elicits a bell-shaped cAMP response. The inhibitory phase of the cAMP response is prevented by pertussis toxin (PTX), consistent with the activation of G(i)-related proteins during depolarization. Agonist activation of the endogenous GnRH receptor in GT1-7 neurons also elicits a bell-shaped change in cAMP production. The inhibitory action of high GnRH concentrations is prevented by PTX, indicating coupling of the GnRH receptors to G(i)-related proteins. The stimulation of cAMP production by activation of endogenous LH receptors is enhanced by low (nanomolar) concentrations of GnRH but is abolished by micromolar concentrations of GnRH, again in a PTX-sensitive manner. These findings indicate that GnRH neuronal cAMP production is maintained by Ca2+ entry through voltage-sensitive calcium channels, leading to activation of Ca2+-stimulated AC I. Furthermore, the Ca2+ influx-dependent activation of AC I acts in conjunction with AC-regulatory G proteins to determine basal and agonist-stimulated levels of cAMP production. 相似文献
85.
A photosynthetic reaction center (RC) complex was isolated from a purple bacterium, Acidiphilium rubrum. The RC contains bacteriochlorophyll a containing Zn as a central metal (Zn-BChl a) and bacteriopheophytin a (BPhe a) but no Mg-BChl a. The absorption peaks of the Zn-BChl a dimer (PZn), the accessory Zn-BChl a (BZn), and BPhe a (H) at 4 K in the RC showed peaks at 875, 792, and 753 nm, respectively. These peaks were shorter than the corresponding peaks in Rhodobacter sphaeroides RC that has Mg-BChl a. The kinetics of fluorescence from PZn*, measured by fluorescence up-conversion, showed the rise and the major decay with time constants of 0.16 and 3.3 ps, respectively. The former represents the energy transfer from BZn* to PZn, and the latter, the electron transfer from PZn to H. The angle between the transition dipoles of BZn and PZn was estimated to be 36° based on the fluorescence anisotropy. The time constants and the angle are almost equal to those in the Rb. sphaeroides RC. The high efficiency of A. rubrum RC seems to be enabled by the chemical property of Zn-BChl a and by the L168HE modification of the RC protein that modifies PZn. 相似文献
86.
Sergej Tomi? Jelena ?oki? Sa?a Vasiliji? Nina Ogrinc Rebeka Rudolf Primo? Pelicon Dragana Vu?evi? Petar Milosavljevi? Sr?a Jankovi? Ivan An?el Jelena Rajkovi? Marjan Slak Rupnik Bernd Friedrich Miodrag ?oli? 《PloS one》2014,9(5)
Gold nanoparticles (GNPs) are claimed as outstanding biomedical tools for cancer diagnostics and photo-thermal therapy, but without enough evidence on their potentially adverse immunological effects. Using a model of human dendritic cells (DCs), we showed that 10 nm- and 50 nm-sized GNPs (GNP10 and GNP50, respectively) were internalized predominantly via dynamin-dependent mechanisms, and they both impaired LPS-induced maturation and allostimulatory capacity of DCs, although the effect of GNP10 was more prominent. However, GNP10 inhibited LPS-induced production of IL-12p70 by DCs, and potentiated their Th2 polarization capacity, while GNP50 promoted Th17 polarization. Such effects of GNP10 correlated with a stronger inhibition of LPS-induced changes in Ca2+ oscillations, their higher number per DC, and more frequent extra-endosomal localization, as judged by live-cell imaging, proton, and electron microscopy, respectively. Even when released from heat-killed necrotic HEp-2 cells, GNP10 inhibited the necrotic tumor cell-induced maturation and functions of DCs, potentiated their Th2/Th17 polarization capacity, and thus, impaired the DCs'' capacity to induce T cell-mediated anti-tumor cytotoxicity in vitro. Therefore, GNP10 could potentially induce more adverse DC-mediated immunological effects, compared to GNP50. 相似文献
87.
Charaf Eddine Watheq Malti Imad Abdelhamid El Haci Faial Hassani Mathieu Paoli Marc Gibernau Flix Tomi Joseph Casanova Chahrazed Bekhechi 《化学与生物多样性》2020,17(6)
Cymbopogon schoenanthus (L.) Spreng . (Poaceae) is an aromatic plant whose aerial parts and rhizome produced an essential oil with pleasant odor. A chemical variability has been observed depending of the countries where the plant grows wild, including Algeria. The chemical compositions of 24 oil samples isolated from plants harvested in Central Algeria have been investigated, to evidence homogeneity or chemical variability within a given area of harvest. Twenty of these were dominated by cis‐ and trans‐p‐menth‐2‐en‐1‐ols (22.6 %±3.6 and 14.3 %±1.7, resp.) beside four atypical compositions. Otherwise, aerial parts and rhizomes produced similar essential oils. Lastly, a fair antimicrobial activity was measured against Staphylococcus aureus strain, while the antioxidant potential was low. 相似文献
88.
Allelic expression mapping across cellular lineages to establish impact of non‐coding SNPs
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89.
Zana Adama Ouattara Jean Brice Boti Koffi Barthelemy Attioua Antoine Coffy Ahibo Joseph Casanova Félix Tomi Ange Bighelli 《化学与生物多样性》2013,10(11):2053-2060
The chemical composition of 48 leaf oil samples isolated from individual plants of Cleistopholis patens (Benth .) Engl. et Diels harvested in four Ivoirian forests was investigated by GC‐FID (determination of retention indices), GC/MS, and 13C‐NMR analyses. The main components identified were β‐pinene (traces–59.1%), sabinene (traces–54.2%), (E)‐β‐caryophyllene (0.3–39.3%), linalool (0.1–38.5%), (E)‐β‐ocimene (0.1–33.2%), germacrene D (0.0–33.1%), α‐pinene (0.1–32.3%), and germacrene B (0–21.2%). The 48 oil compositions were submitted to hierarchical clustering and principal components analyses, which allowed the distinction of three groups within the oil samples. The oil composition of the major group (Group I, 33 samples) was dominated by (E)‐β‐caryophyllene and linalool. The oils of Group II (eight samples) contained mainly β‐pinene and α‐pinene, while those of Group III (seven samples) were dominated by sabinene, limonene, and β‐phellandrene. Moreover, the compositions of the Ivoirian C. patens leaf oils differed from those of Nigerian and Cameroonian origins. 相似文献
90.
Cicadivetta goumenissa, a small singing cicada described recently by Gogala et al. (2012), has been previously found only around the village of Goumenissa in northern Peloponnese. We visited this area again in June 2012 and tried to determine the distribution range of this species. We found Cicadivetta goumenissa in some further localities, but all within a very small area of about 15 by 25 km. We also made more than one hour of new song recordings and extended our knowledge of the song repertoire of this species. 相似文献