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81.
Hwei-Ru Tsou Gloria MacEwan Gary Birnberg George Grosu Matthew G. Bursavich Joel Bard Natasja Brooijmans Lourdes Toral-Barza Irwin Hollander Tarek S. Mansour Semiramis Ayral-Kaloustian Ker Yu 《Bioorganic & medicinal chemistry letters》2010,20(7):2321-2325
We discovered 2-(4-substituted-pyrrolo[2,3-b]pyridin-3-yl)methylene-4-hydroxybenzofuran-3(2H)-ones as potent and selective ATP-competitive inhibitors of the mammalian target of rapamycin (mTOR). Since phenolic OH groups pose metabolic liability, one of the two hydroxyl groups was selectively removed. The SAR data showed the structural features necessary for subnanomolar inhibitory activity against mTOR kinase as well as selectivity over PI3Kα. An X-ray co-crystal structure of one inhibitor with the mTOR-related PI3Kγ revealed the key hydrogen bonding interactions. 相似文献
82.
Crina Cismaş Nicolas Vanthuyne Hélène Rispaud Richard Attila Varga Elena Bogdan Christian Roussel Ion Grosu 《Chirality》2011,23(2):167-171
The first geometric enantiomers in the cyclic compounds series are reported. The investigated compounds are 2,2‐disubstituted‐5‐methyl‐1,3‐dioxane derivatives in which the substituents at position 2 bear chiral centers with identical substituents but with opposite configurations. The structure of the unlike isomers was determined from the solid state molecular structure of the compounds obtained by single crystal X‐ray diffractometry and the enantiomers of these diastereoisomers were observed by chiral column HPLC base‐line separation. The investigated compounds were obtained by a diastereoselective bromination reaction of the corresponding 2,2‐dialkyl and 2,2‐dibenzyl‐5‐methyl‐1,3‐dioxanes. Chirality, 2011. © 2010 Wiley‐Liss, Inc. 相似文献
83.
Koci J Movila A Taragel'ová V Toderas I Uspenskaia I Derdáková M Labuda M 《Experimental & applied acarology》2007,41(1-2):147-152
We examined 198 questing Ixodes ricinus ticks collected in Chisinau City, Republic of Moldova by PCR assays for Anaplasma phagocytophilum, Borrelia burgdorferi sensu lato and co-infection of both pathogens, which were detected in 9%, 25.2% and 2.5% of tested ticks, respectively. B. burgdorferi s.l. genotyping revealed the presence of five genospecies with dominance of B. garinii. Our preliminary study provides evidence about occurrence of both pathogens in this populated area, which represent a potential
health risk for inhabitants. 相似文献
84.
Romulus Ion Scorei Cristina Ciofrangeanu Raluca Ion Anisoara Cimpean Bianca Galateanu Valentina Mitran Dana Iordachescu 《Biological trace element research》2010,135(1-3):334-344
The present study is supported by our previous findings suggesting that calcium fructoborate (CF) has anti-inflammatory and antioxidant properties. Thus, we investigated the effects of CF on a model for studying inflammatory disorders in vitro represented by lipopolysaccharide (LPS)-stimulated murine macrophage RAW 264.7 cells. This investigation was performed by analyzing the levels of some mediators released during the inflammatory process: cytokines such as tumor necrosis factor-α (TNF-α), interleukins IL-1β and IL-6 as well as cyclooxygenase-2 (COX-2), the main enzyme responsible for endotoxin/LPS-induced prostaglandin synthesis by macrophages. We also measured production of nitric oxide (NO) that plays an important role in the cytotoxicity activity of macrophages towards microbial pathogens. After CF treatment of LPS-stimulated macrophages we found an up-regulation of TNF-α protein level in culture medium, no significant changes in the level of COX-2 protein expression and a decrease in NO production as well as in IL-1β and IL-6 release. Collectively, this series of experiments indicate that CF affect macrophage production of inflammatory mediators. However, further research is required in order to establish whether CF treatment can be beneficial in suppression of pro-inflammatory cytokine production and against progression of endotoxin-related diseases. 相似文献
85.
86.
Alexandru Movila Helen V. Dubinina Natalia Sitnicova Liubov Bespyatova Inga Uspenskaia Galina Efremova Ion Toderas Andrey N. Alekseev 《Experimental & applied acarology》2014,63(1):65-76
Characterizing the tick-borne microorganism communities of Ixodes ricinus (sheep tick) and Ixodes persulcatus (taiga tick) from the I. ricinus species complex in distinct geographical regions of Eastern Europe and European Russia, we demonstrated differences between the two ticks. Taiga ticks were more frequently mono- and co-infected than sheep ticks: 24.4 % (45/184 tested ticks) versus 17.5 % (52/297) and 4.3 % (8/184) versus 3.4 % (10/297), respectively. Ginsberg co-infection index values were significant at the various sites. Diversity of the tick-borne microorganism communities was estimated by the Shannon index, reaching values of 1.71 ± 0.46 and 1.20 ± 0.15 at the sheep-tick and the taiga-tick harbored sites, respectively. Richness of the tick-borne microorganism community in the sheep tick collection sites was about twice the value of the taiga tick collection sites. Future investigations are warranted to further characterize the peculiarities of the tick-borne microorganism communities among the ticks of the Ixodes ricinus complex. 相似文献
87.
We have previously developed a software package called PrimerHunter to design primers for PCR-based virus subtyping. In this study, 9 pairs of primers were designed with PrimerHunter and successfully used to differentiate the 9 neuraminidase (NA) genes of avian influenza viruses (AIVs) in multiple PCR-based assays. Furthermore, primer pools were designed and successfully used to decrease the number of reactions needed for NA subtyping from 9 to 4. The quadruplicate primer-pool method is cost-saving, and was shown to be suitable for the NA subtyping of both cultured AIVs and uncultured AIV swab samples. The primers selected for this study showed excellent sensitivity and specificity in NA subtyping by RT-PCR, SYBR green-based Real-time PCR and Real-time RT-PCR methods. AIV RNA of 2 to 200 copies (varied by NA subtypes) could be detected by these reactions. No unspecific amplification was displayed when detecting RNAs of other avian infectious viruses such as Infectious bronchitis virus, Infectious bursal disease virus and Newcastle disease virus. In summary, this study introduced several sensitive and specific PCR-based assays for NA subtyping of AIVs and also validated again the effectiveness of the PrimerHunter tool for the design of subtyping primers. 相似文献
88.
89.
Change of strategy or always overlooked? Third recent record of the beardless tadpole goby Benthophiloides brauneri from an inland location far from the coast 下载免费PDF全文
The present study documents three specimens of Benthophiloides brauneri from the River Dniester. It is one of the rarest freshwater fishes in Europe, living along the western coast of the Black and Asov Seas, but these new records are 200 river km from the coast. We discuss whether the species has recently started to establish inland populations or inland specimens have previously been overlooked. 相似文献
90.
Calcium fructoborate is a boron-based nutritional supplement. Its chemical structure is similar to one of the natural forms
of boron such as bis-manitol, bis-sorbitol, bis-fructose, and bis-sucrose borate complexes found in edible plants. In vitro studies revealed that calcium fructoborate is a superoxide ion
scavenger and anti-inflammatory agent. It may influence macrophage production of inflammatory mediators, can be beneficial
for the suppression of cytokine production, and inhibits progression of endotoxin-associated diseases, as well as the boric
acid and other boron sources. The mechanisms by which calcium fructoborate exerts its beneficial anti-inflammatory effects
are not entirely clear, but some of its molecular biological in vitro activities are understood: inhibition of the superoxide
within the cell; inhibition of the interleukin-1β, interleukin-6, and nitric oxide release in the culture media; and increase
of the tumor necrosis factor-α production. Also, calcium fructoborate has no effects on lipopolysaccharide-induced cyclooxygenase-2
protein express. The studies on animals and humans with a dose range of 1–7 mg calcium fructoborate (0.025–0.175 mg elemental
boron)/kg body weight/day exhibited a good anti-inflammatory activity, and it also seemed to have negligible adverse effect
on humans. 相似文献