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31.
On‐chip assessment of human primary cardiac fibroblasts proliferative responses to uniaxial cyclic mechanical strain 下载免费PDF全文
32.
The terrestrial lizard Podarcis siculus is the most abundant reptile in Italy, where is considered a ubiquitous species. This lizard is widely distributed from the islands to the Apennines, from cultivated fields to anthropized areas such as gardens and city parks. For this reason, these animals are exposed to extensive physical and chemical stresses, as well as to the possibility of coming into contact with industrial pollutants and substances used in agricultural practices. Here, we review the health status of lizard specimens inhabiting natural non-anthropized areas and fields devoted to organic farming, considering the condition of (1) liver, representing the main detoxifying organ, directly influenced by feeding, and (2) gonads, essential for reproduction and, therefore, for the survival of the species. The morphological and biomolecular condition of these organs was then compared with those obtained from lizard specimens experimentally treated with nonylphenol, a co-formulant of many insecticides and plant protection products widely used in conventional farming, known to have harmful estrogenic effects. Taken together, data demonstrate that lizards inhabiting manured soil are in good health status and show a regular morphology of liver, testis, and ovary. Animals are found to be less exposed to the toxic heavy metals cadmium and lead if compared with specimens collected in areas not devoted to agriculture, but probably more exposed to vehicular traffic. However, manure, as well as nonylphenol, exerts a xeno-estrogenic effect, particularly evident in male specimens, more sensitive to estrogenic contamination. 相似文献
33.
Michela Buccioni Diego Dal Ben Catia Lambertucci Aleix Martí Navia Massimo Ricciutelli Andrea Spinaci Rosaria Volpini Gabriella Marucci 《Bioorganic & medicinal chemistry》2019,27(15):3328-3333
In recent years, special attention has been paid to the A3 adenosine receptor (A3AR) as a possible pharmacological target to treat intestinal inflammation. In this work, it was set up a novel method to quantify the concentration of a promising anti-inflammatory agent inside and outside of intestinal barrier using the everted gut sac technique. The compound chosen for the present study is one of the most potent and selective A3AR agonist reported so far, named AR 170 (N6-methyl-2-phenylethynyl-5′-N-methylcarboxamidoadenosine). In order to evaluate the intestinal absorption of AR 170 the radioligand binding assay in comparison with HPLC-DAD was used. Results showed that the compound is absorbed via passive diffusion by paracellular pathway. The concentrations determined in the serosal (inside the sac) fluid by radioligand binding assay are in good agreement with those obtained through the widely used HPLC/MS protocol, demonstrating the reliability of the method. It is worthwhile to note that the radioligand binding assay allows detecting very low concentrations of analyte, thus offering an excellent tool to measure the intestinal absorption of receptor ligands. Moreover, the AR 170 quantity outside the gut sac and the interaction with A3AR could presuppose good topical anti-inflammatory effects of this compound. 相似文献
34.
Gong Chang Cheng Ziliang Yang Yaping Shen Jun Zhu Yingying Ling Li Lin Wanyi Yu Zhigang Li Zhihua Tan Weige Zheng Chushan Zheng Wenbo Zhong Jiajie Zhang Xiang Zeng Yunjie Liu Qiang Huang R. Stephanie Komorowski Andrzej L. Yang Eddy S. Bertucci François Ricci Francesco Orlandi Armando Franceschini Gianluca Takabe Kazuaki Klimberg Suzanne Ishii Naohiro Toss Angela Tan Mona P. Cherian Mathew A. Song Erwei 《中国科学:生命科学英文版》2022,65(11):2205-2217
Science China Life Sciences - Patients with hormone receptor (HR)-positive tumors breast cancer usually experience a relatively low pathological complete response (pCR) to neoadjuvant chemotherapy... 相似文献
35.
Lambertucci C Cristalli G Dal Ben D Kachare DD Bolcato C Klotz KN Spalluto G Volpini R 《Purinergic signalling》2007,3(4):339-346
A new series of 2,6,9-trisubstituted adenines (5–14) have been prepared and evaluated in radioligand binding studies for their affinity at the human A1, A2A and A3 adenosine receptors and in adenylyl cyclase experiments for their potency at the human A2B subtype. From this preliminary study the conclusion can be drawn that introduction of bulky chains at the N
6 position of 9-propyladenine significantly increased binding affinity at the human A1 and A3 adenosine receptors, while the presence of a chlorine atom at the 2 position resulted in a not univocal effect, depending
on the receptor subtype and/or on the substituent present in the N
6 position. However, in all cases, the presence in the 2 position of a chlorine atom favoured the interaction with the A2A subtype. These results demonstrated that, although the synthesized compounds were found to be quite inactive at the human
A2B subtype, adenine is a useful template for further development of simplified adenosine receptor antagonists with distinct
receptor selectivity profiles. 相似文献
36.
A. Padiglia Rosaria Medda Jens Z. Pedersen Alessandro Finazzi Agrò Anita Lorrai Barbara Murgia Giovanni Floris 《Journal of biological inorganic chemistry》1999,4(5):608-613
The reaction with substrates and carbonyl reagents of native lentil Cu-amine oxidase and its modified forms, i.e. Cu-fully-depleted,
Cu-half-reconstituted, Cu-fully-reconstituted, Co-substituted, Ni-substituted and Zn-substituted, has been studied. Upon removal
of only one of the two Cu ions, the enzyme loses 50% of its enzymatic activity. Using several substrates, Co-substituted lentil
amine oxidase is shown to be active but the k
c value is different from that of native or Cu-fully-reconstituted enzyme, while K
m is similar. On the other hand, the Ni- and Zn-substituted forms are catalytically inactive. Enzymatic activity measurements
and optical spectroscopy show that only in the Co-substituted enzyme is the organic cofactor 6-hydroxydopa quinone reactive
and the enzyme catalytically competent, although less efficient. The Co-substituted amine oxidase does not form the semiquinone
radical as an intermediate of the catalytic reaction. While devoid or reduced of catalytic activity, all the enzyme preparations
are still able to oxidise two moles of substrate and to release two moles of aldehyde per mole of dimeric enzyme. The results
obtained show that although Co-substituted amine oxidase is catalytically competent, copper is essential for the catalytic
mechanism.
Received: 5 March 1999 / Accepted: 22 July 1999 相似文献
37.
Botelho MV Orlandi JM de Melo FL Mantovani MS Linhares RE Nozawa C 《Letters in applied microbiology》2004,39(2):174-177
AIMS: Chlorophyllin (CHLN) is a synthetic derivative of chlorophyll that possesses antimutagenic activity against several environmental contaminants. In the present study, CHLN was assayed for its capacity to prevent nuclear fragmentation (NF) in HEp-2 cells infected with poliovirus. METHODS AND RESULTS: CHLN was assayed at concentrations of 0.5 and 2.5 microg ml(-1), and NF was monitored using the comet assay and acridine orange staining. We demonstrated that CHLN reduced the percentage of NF in poliovirus-infected HEp-2 cells, when cells were treated with drug before infection or exposed continuously to drug. However, the highest degree of protection was achieved when the virus was exposed to CHLN before infection followed by protocol where infected cultures were continuously exposed to the drug after infection. CONCLUSIONS: It is suggested that CHLN primarily binds to the virus which inhibits cell penetration, thereby maintaining nuclear integrity. SIGNIFICANCE AND IMPACT OF THE STUDY: Considering that CHLN has several beneficial properties and no significant toxic effects in humans and animals, it would be an ideal candidate drug to test for antiviral activity. 相似文献
38.
39.
Cold-adapted organisms have developed a number of adjustments at the molecular level to maintain metabolic functions at low temperatures. Among other features, they can produce enzymes characterized by a high turnover number or a high catalytic efficiency. The present work is aimed at investigating the process of food digestion at low temperature through the study of pepsins in Antarctic notothenioids. For such a purpose, we have cloned and sequenced three forms of pepsin A and a single form of gastricsin from the gastric mucosa of Trematomus bernacchii (rock cod). Phylogenetic analysis has suggested that the three pepsin A isotypes arose from two gene duplication events leading to the most ancestral pepsin A3 and to the most recent forms represented by pepsin A1 and pepsin A2. Molecular modeling has unraveled significant structural differences in these enzymes with respect to their mesophilic counterparts. Hydropathy and flexibility determined on the substrate-binding subsites of Antarctic and mesophilic pepsins have shown for pepsin A2 reduced hydropathy and increased flexibility at the level of the substrate cleft, features typical of cold-adapted enzymes. Northern blot analysis of RNA from rock cod gastric mucosa hybridized with molecular probes designed on specific regions of different pepsin forms has shown that rock cod pepsin genes are expressed at comparable levels. The present results suggest that the Antarctic rock cod adopted two different strategies to accomplish efficient protein digestion at low temperature. One mechanism is the gene duplication that increases enzyme production to compensate for the reduced kinetic efficiency, the other is the expression of a new enzyme provided with features typical of cold-adapted enzymes. 相似文献
40.