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991.
Theunissen EL Kauert GF Toennes SW Moeller MR Sambeth A Blanchard MM Ramaekers JG 《Psychopharmacology》2012,220(2):341-350
Rationale
Experienced cannabis users demonstrate tolerance to some of the impairing acute effects of cannabis. 相似文献992.
Elliott A Joiakim A Mathieu PA Duniec-Dmuchowski Z Kocarek TA Reiners JJ 《Drug metabolism and disposition》2012,40(5):1032-1040
The aryl hydrocarbon receptor (AhR) is targeted by ubiquitination for degradation by the proteasome shortly after its activation by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). In silico screening identified p-anilinoaniline (pAA) as a putative inhibitor of an E2 ligase that partners with an E3 ligase implicated in AhR ubiquitination. We investigated whether pAA could modify AhR-dependent activation of its target gene CYP1A1. pAA (1-200 μM) alone did not affect AhR content, or stimulate CYP1A1 mRNA accumulation in human mammary epithelial MCF10A cultures. However, pretreatment with ≥100 μM pAA suppressed TCDD-induced CYP1A1 activation and AhR degradation via its functioning as an AhR antagonist. At a lower concentration (25 μM), pAA cotreatment increased TCDD-induced CYP1A1 mRNA accumulation, without inhibiting AhR turnover or altering CYP1A1 mRNA half-life. Whereas TCDD alone did not affect MCF10A proliferation, 25 μM pAA was cytostatic and induced a G(1) arrest that lasted ~7 h and induced an S phase arrest that peaked 5 to 8 h later. TCDD neither affected MCF10A cell cycle progression nor did it alter pAA effects on the cell cycle. The magnitude of CYP1A1 activation depended upon the time elapsed between pAA pretreatment and TCDD addition. Maximal AhR occupancy of the CYP1A1 promoter and accumulation of CYP1A1 heterogeneous nuclear RNA and mRNA occurred when pAA-pretreated cultures were exposed to TCDD in late G(1) and early/mid S phase. TCDD-mediated induction of CYP2S1 was also cell cycle-dependent in MCF10A cultures. Similar studies with HepG2 cultures indicated that the cell cycle dependence of CYP1A1 induction is cell context-dependent. 相似文献
993.
The use of phantoms comprising diluted tissue homogenates with a buried capillary containing quantum dots is demonstrated as a method to investigate the optical and biophysical factors influencing the imaging of subsurface fluorescence contrast agents. Validation of the method is demonstrated using both liquid phantoms of known optical absorption and reduced scattering and Monte Carlo computer simulations of photon transport. Conclusions regarding the optimal excitation wavelength are given and quantified with respect to the tissue optical properties. The tissue homogenate method should be of value for quantitative optimization studies relevant to, for example, endoscopic imaging. 相似文献
994.
Maurin M Stéphan O Vial JC Marder SR van der Sanden B 《Journal of biomedical optics》2011,16(3):036001
Our purpose is to test if Pluronic? fluorescent nanomicelles can be used for in vivo two-photon imaging of both the normal and the tumor vasculature. The nanomicelles were obtained after encapsulating a hydrophobic two-photon dye: di-stryl benzene derivative, in Pluronic block copolymers. Their performance with respect to imaging depth, blood plasma staining, and diffusion across the tumor vascular endothelium is compared to a classic blood pool dye Rhodamin B dextran (70 kDa) using two-photon microscopy. Pluronic nanomicelles show, like Rhodamin B dextran, a homogeneous blood plasma staining for at least 1 h after intravenous injection. Their two-photon imaging depth is similar in normal mouse brain, using 10 times less injected mass. In contrast with Rhodamin B dextran, no extravasation is observed in leaky tumor vessels due to their large size: 20-100 nm. In conclusion, Pluronic nanomicelles can be used as a blood pool dye, even in leaky tumor vessels. The use of Pluronic block copolymers is a valuable approach for encapsulating two-photon fluorescent dyes that are hydrophobic and not suitable for intravenous injection. 相似文献
995.
Puente N Cui Y Lassalle O Lafourcade M Georges F Venance L Grandes P Manzoni OJ 《Nature neuroscience》2011,14(12):1542-1547
The reason why neurons synthesize more than one endocannabinoid (eCB) and how this is involved in the regulation of synaptic plasticity in a single neuron is not known. We found that 2-arachidonoylglycerol (2-AG) and anandamide mediate different forms of plasticity in the extended amygdala of rats. Dendritic L-type Ca(2+) channels and the subsequent release of 2-AG acting on presynaptic CB1 receptors triggered retrograde short-term depression. Long-term depression was mediated by postsynaptic mGluR5-dependent release of anandamide acting on postsynaptic TRPV1 receptors. In contrast, 2-AG/CB1R-mediated retrograde signaling mediated both forms of plasticity in the striatum. These data illustrate how the eCB system can function as a polymodal signal integrator to allow the diversification of synaptic plasticity in a single neuron. 相似文献
996.
997.
Bavu E Gennisson JL Couade M Bercoff J Mallet V Fink M Badel A Vallet-Pichard A Nalpas B Tanter M Pol S 《Ultrasound in medicine & biology》2011,37(9):1361-1373
Supersonic shear imaging (SSI) has recently been demonstrated to be a repeatable and reproducible transient bidimensional elastography technique. We report a prospective clinical evaluation of the performances of SSI for liver fibrosis evaluation in 113 patients with hepatitis C virus (HCV) and a comparison with FibroScan (FS). Liver elasticity values using SSI and FS ranged from 4.50 kPa to 33.96 kPa and from 2.60 kPa to 46.50 kPa, respectively. Analysis of variance (ANOVA) shows a good agreement between fibrosis staging and elasticity assessment using SSI and FS (p < 10−5). The areas under receiver operating characteristic (ROC) curves for elasticity values assessed from SSI were 0.948, 0.962 and 0.968 for patients with predicted fibrosis levels F ≥ 2, F ≥ 3 and F = 4, respectively. These values are compared with FS area under the receiver operating characteristic curve (AUROC) of 0.846, 0.857 and 0.940, respectively. This comparison between ROC curves is particularly significant for mild and intermediate fibrosis levels. SSI appears to be a fast, simple and reliable method for noninvasive liver fibrosis evaluation. 相似文献
998.
Gelhaye M Padzys GS Olry JC Thornton SN Martrette JM Trabalon M 《Developmental psychobiology》2011,53(3):303-316
The effects of short-term bilateral naris occlusion (inducing olfactory deprivation) on mother-pup interactions, suckling behavior and hormonal status during post-natal development in Wistar rats were studied. Bilateral naris occlusion was performed on 8-day-old rat pups and its effects were evaluated at Day 9 and at Day 15. The narins opened spontaneously between Day 12 and 14. Olfactory-deprived pups exhibited a greater level of corticosterone at both ages versus untreated or sham animals. Olfactory deprivation via naris occlusion, in young rats, alters mother-pup interactions with a decrease in the duration of mother-pup retrieving and an increase in pup licking. Olfactory-deprived pups showed also a lower mean duration of nursing and a decrease in nipple attachment, which appeared related to difficulties in finding the nipple. Olfactory-deprived pups had difficulty recognizing their nest. These behavioral alterations were accompanied by a diminution in milk ingested and growth retardation associated with a reduced level of thyroxin at both 9 and 15 days of age. 相似文献
999.
Rodríguez SM Florins A Gillet N de Brogniez A Sánchez-Alcaraz MT Boxus M Boulanger F Gutiérrez G Trono K Alvarez I Vagnoni L Willems L 《Viruses》2011,3(7):1210-1248
Bovine leukemia virus (BLV) is a retrovirus closely related to the human T-lymphotropic virus type 1 (HTLV-1). BLV is a major animal health problem worldwide causing important economic losses. A series of attempts were developed to reduce prevalence, chiefly by eradication of infected cattle, segregation of BLV-free animals and vaccination. Although having been instrumental in regions such as the EU, these strategies were unsuccessful elsewhere mainly due to economic costs, management restrictions and lack of an efficient vaccine. This review, which summarizes the different attempts previously developed to decrease seroprevalence of BLV, may be informative for management of HTLV-1 infection. We also propose a new approach based on competitive infection with virus deletants aiming at reducing proviral loads. 相似文献
1000.
Baptiste Coustet Philippe Dieud Mickael Guedj Mathieu Bouaziz Jerome Avouac Barbara Ruiz Eric Hachulla Elisabeth Diot Jean‐Luc Cracowski Kiet Tiev Jean Sibilia Luc Mouthon Camille Frances Zahir Amoura Patrick Carpentier Anne Cosnes Olivier Meyer Andre Kahan Catherine Boileau Gilles Chiocchia Yannick Allanore 《Arthritis \u0026amp; Rheumatology》2011,63(7):2091-2096