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81.
82.
R. Albrecht T. C. Awes P. Beckmann F. Berger D. Bock R. Bock G. Claesson G. Clewing L. Dragon A. Eklund R. L. Ferguson A. Franz S. Garpman R. Glasow H. Å. Gustafsson H. H. Gutbrod G. Hölker J. Idh P. Jacobs K. H. Kampert B. W. Kolb P. Kristiansson H. Löhner I. Lund F. E. Obenshain A. Oskarsson I. Otterlund T. Peitzmann F. Plasil A. M. Poskanzer M. Purschke H. G. Ritter R. Santo S. Saini H. R. Schmidt S. P. Sørensen K. Steffens D. Stüken E. Stenlund M. Tincknell G. R. Young 《Zeitschrift fur Physik C Particles and Fields》1991,51(1):1-10
The production of direct photons has been investigated in reactions ofp and16O projectiles at 60 and 200A·GeV with C and Au nuclei. Photon and 0 spectra have been measured in the pseudorapidity range 1.52.1 for the transverse momentum region 0.4 GeV/cp
T
2.8 GeV/c employing the lead-glass spectrometer SAPHIR. An upper limit of 15% at the 90% confidence level for the direct photon signal relative to the neutral pion production is obtained from the comparison of measured photon spectra with Monte Carlo simulations of the hadronic background based on the reconstructed yield of 0 and mesons. Consequences for a possible phase transition to a quark-gluon plasma are discussed. 相似文献
83.
84.
Straub PB Jaffe DE Glass HD Adams MR Brown CN Charpak G Cooper WE Crittenden JA Finley DA Gray R Hemmi Y Hsiung YB Hubbard JR Jonckheere AM Jöstlein H Kaplan DM Lederman LM Luk KB Maki A Mangeot P McCarthy RL Miyake K Plaag RE Rutherfoord JP Sakai Y Santiard JC Sauli F Smith SR Yoshida T Young KK 《Physical review letters》1992,68(4):452-455
85.
86.
Melvyn Rowen Churchill Clifford Bueno David A. Young 《Journal of organometallic chemistry》1981,213(1):139-150
The species FeRu3(CO)13(μ-PPH2)2, synthesized from Ru3(CO)12 and Fe(CO)4(Ph2PPPh2),has been characterized both spectroscopically and via a single-crystal X-ray structural analysis. This complex crystallizes in the centrosymmetric triclinic space group P [No. 2, Ci1] with a 10.066(3), b 12.899(3), c 17.003(4) Å, α 111.89(2), β 91.02(2), γ 102.00(2)°, V 1992.7(9) Å3, Z 2, ?(obsd) 1.79(2) g cm-3 and ?(calcd) 1.82 cm-3. Diffraction data were collected with a Syntex P21 automated four-circle diffractometer and the structure was refined to RF 6.0% and RWF 3.6% for all 5213 reflections (RF 3.8%, RWF 3.6% for those 4140 reflections with |Fo|> 3σ(|Fo|).The metal atoms define a planar triangulated rhombus, with atoms Ru(1) and Ru(2) at the bridgehead, and Fe(1) and Ru(3) at the acute apices. Fe(1) is linked to four terminal carbonyl ligands and is associated with the heteronuclear bonds Fe(1)Ru(1) 2.861(1) Å and Fe(1)Ru(2) 2.868(1) Å. The ruthenium atoms are each bonded to three terminal carbonyl groups. The retheniumruthenium distances are Ru(1)Ru(2) 3.098(1), Ru(1)Ru(3) 3.147(1), and Ru(2)Ru(3) 3.171(1) Å. The structure is completed by Ph2P bridges across the Ru(1)Ru(3) and Ru(2)(ru(3) vectors (<Ru(1)P(1)Ru(3) 84.89(5)° and <Ru(2)P(2)Ru(3) 85.56(6)°). 相似文献
87.
Na Young Kim Chakrabhavi Dhananjaya Mohan Arunachalam Chinnathambi Sulaiman Ali Alharbi Gautam Sethi Kanchugarakoppal S. Rangappa Kwang Seok Ahn 《Molecules (Basel, Switzerland)》2022,27(12)
EGFR and Wnt/β-catenin signaling pathways play a prominent role in tumor progression in various human cancers including non-small-cell lung carcinoma (NSCLC). Transactivation and crosstalk between the EGFR and Wnt/β-catenin pathways may contribute to the aggressiveness of cancers. Targeting these oncogenic pathways with small molecules is an attractive approach to counteract various types of cancers. In this study, we demonstrate the effect of euphorbiasteroid (EPBS) on the EGFR and Wnt/β-catenin pathways in NSCLC cells. EPBS induced preferential cytotoxicity toward A549 (wildtype EGFR-expressing) cells over PC-9 (mutant EGFR-expressing) cells. EPBS suppressed the expression of EGFR, Wnt3a, β-catenin, and FZD-1, and the reduction in β-catenin levels was found to be mediated through the activation of GSK-3β. EPBS reduced the phosphorylation of GSK-3βS9 with a parallel increase in β-TrCP and phosphorylation of GSK-3βY216. Lithium chloride treatment increased the phosphorylation of GSK-3βS9 and nuclear localization of β-catenin, whereas EPBS reverted these effects. Forced expression or depletion of EGFR in NSCLC cells increased or decreased the levels of Wnt3a, β-catenin, and FZD-1, respectively. Overall, EPBS abrogates EGFR and Wnt/β-catenin pathways to impart its anticancer activity in NSCLC cells. 相似文献
88.
Steven Elder John Graham Roberson James Warren Robert Lawson Daniel Young Sean Stokes Matthew K. Ross 《Molecules (Basel, Switzerland)》2022,27(12)
In this study, kartogenin was incorporated into an electrospun blend of polycaprolactone and poly(lactic-co-glycolic acid) (1:1) to determine the feasibility of this system for sustained drug delivery. Kartogenin is a small-molecule drug that could enhance the outcome of microfracture, a cartilage restoration procedure, by selectively stimulating chondrogenic differentiation of endogenous bone marrow mesenchymal stem cells. Experimental results showed that kartogenin did not affect the electrospinnability of the polymer blend, and it had negligible effects on fiber morphology and scaffold mechanical properties. The loading efficiency of kartogenin into electrospun membranes was nearly 100%, and no evidence of chemical reaction between kartogenin and the polymers was detected by Fourier transform infrared spectroscopy. Analysis of the released drug using high-performance liquid chromatography–photodiode array detection indicated an abundance of kartogenin and only a small amount of its major hydrolysis product. Kartogenin displayed a typical biphasic release profile, with approximately 30% being released within 24 h followed by a much slower, constant rate of release up to 28 days. Although additional development is needed to tune the release kinetics and address issues common to electrospun scaffolds (e.g., high fiber density), the results of this study demonstrated that a scaffold electrospun from biodegradable synthetic polymers is a suitable kartogenin delivery vehicle. 相似文献
89.
Suvarna H. Pagire Haushabhau S. Pagire Kun-Young Park Eun Jung Bae Kwang-eun Kim Minhee Kim Jihyeon Yoon Saravanan Parameswaran Jun-Ho Choi Sungmi Park Jae-Han Jeon Jin Sook Song Myung Ae Bae In-Kyu Lee Hail Kim Jae Myoung Suh Jin Hee Ahn 《Molecules (Basel, Switzerland)》2022,27(11)
Serotonin (5-hydroxytryptophan) is a hormone that regulates emotions in the central nervous system. However, serotonin in the peripheral system is associated with obesity and fatty liver disease. Because serotonin cannot cross the blood-brain barrier (BBB), we focused on identifying new tryptophan hydroxylase type I (TPH1) inhibitors that act only in peripheral tissues for treating obesity and fatty liver disease without affecting the central nervous system. Structural optimization inspired by para-chlorophenylalanine (pCPA) resulted in the identification of a series of oxyphenylalanine and heterocyclic phenylalanine derivatives as TPH1 inhibitors. Among these compounds, compound 18i with an IC50 value of 37 nM was the most active in vitro. Additionally, compound 18i showed good liver microsomal stability and did not significantly inhibit CYP and Herg. Furthermore, this TPH1 inhibitor was able to actively interact with the peripheral system without penetrating the BBB. Compound 18i and its prodrug reduced body weight gain in mammals and decreased in vivo fat accumulation. 相似文献
90.
Mi-Jin Kwon Ju-Woon Lee Kwan-Soo Kim Hao Chen Cheng-Bi Cui Gye Won Lee Young Ho Cho 《Molecules (Basel, Switzerland)》2022,27(14)
Alzheimer’s disease (AD) is an age-related neurodegenerative disorder characterized by cognitive deficits, which are accompanied by memory loss and cognitive disruption. Rhodiola sachalinensis (RSE) is a medicinal plant that has been used in northeastern Asia for various pharmacological activities. We attempted to carry out the bioconversion of RSE (Bio-RSE) using the mycelium of Bovista plumbe to obtain tyrosol-enriched Bio-RSE. The objective of this study was to investigate the effects of Bio-RSE on the activation of the cholinergic system and the inhibition of oxidative stress in mice with scopolamine (Sco)-induced memory impairment. Sco (1 mg/kg body weight, i.p.) impaired the mice’s performance on the Y-maze test, passive avoidance test, and water maze test. However, the number of abnormal behaviors was reduced in the groups supplemented with Bio-RSE. Bio-RSE treatment improved working memory and avoidance times against electronic shock, increased step-through latency, and reduced the time to reach the escape zone in the water maze test. Bio-RSE dramatically improved the cholinergic system by decreasing acetylcholinesterase activity and regulated oxidative stress by increasing antioxidant enzymes (superoxide dismutase (SOD) and catalase (CAT)). The reduction in nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling in the brain tissue due to scopolamine was restored by the administration of Bio-RSE. Bio-RSE also significantly decreased amyloid-beta 1–42 (Aβ1–42) and amyloid precursor protein (APP) expression. Moreover, the increased malondialdehyde (MDA) level and low total antioxidant capacity in Sco-treated mouse brains were reversed by Bio-RSE, and an increase in Nrf2 and HO-1 was also observed. In conclusion, Bio-RSE protected against Sco-induced cognitive impairment by activating Nrf2/HO-1 signaling and may be developed as a potential beneficial material for AD. 相似文献