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101.
Pekmez H Kus I Colakoglu N Ogeturk M Ozyurt H Turkoglu AO Sarsilmaz M 《Cell biochemistry and function》2007,25(4):395-400
The aim of this study was to investigate the histological and biochemical changes in liver of rats exposed to cigarette smoke and effects of caffeic acid phenetyl ester (CAPE) on these changes. For this purpose, 21 male Wistar rats were divided into three groups. Animals in Group I were used as control. Rats in Group II were exposed to cigarette smoke and rats in Group III were exposed to cigarette smoke and injected daily with CAPE. At the end of the 60-days experimental period, all rats were killed by decapitation and blood samples were obtained. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin levels and hepatic superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px ), malondialdehyde (MDA) contents were determined. Following routine histological procedures, liver tissue specimens were examined under a light microscope. The levels of ALT, AST, total bilirubin, SOD, GSH-Px and MDA were significantly increased in rats exposed to cigarette smoke compared with those of the controls. Light microscopic examination of liver specimens from rats exposed to cigarette smoke revealed mononuclear cell infiltration and that some of the hepatocytes had a hyperchromatic nucleus and enlarged sinusoids. The rats which were treated with CAPE along with cigarettes had partially attenuated histological changes associated with cigarette exposure. In conclusion, the damage inflicted by cigarette in the rat liver can be partially prevented by CAPE administration. 相似文献
102.
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is a carcinogenic compound of cigarette smoke that generates electrophilic
intermediates capable of damaging DNA. Recently, we have shown that NNK can modulate mediator production by alveolar macrophages
(AM) and bronchial and alveolar epithelial cells, suggesting that cigarette smoke can alter lung immune response. Thus, we
investigated the effect of NNK and cigarette smoke extract (CSE) on AM capacity to eliminate tumoral cells. Rat AM cell line,
NR8383, was treated with NNK (500 μM) or CSE (3%) and stimulated with lipopolysaccharide (10 ng/ml). The release of cytotoxic
mediators, tumor necrosis factor (TNF) and reactive oxygen species (ROS), was measured in cell-free supernatants using ELISA
and superoxide anion production. TNF- and ROS-dependent cytotoxicity were studied using a 51Chromium-release assay and WEHI-164 and P-815 cell lines. Treatment of AM with NNK and CSE for 18 h significantly inhibited
AM TNF release. CSE exposure resulted in a significant increase of ROS production, whereas NNK did not. TNF-dependent cytotoxic
activity of NR8383 and freshly isolated rat AM was significantly inhibited after treatment with NNK and CSE. Interestingly,
although ROS production was stimulated by CSE and not affected by NNK, CSE inhibited AM ROS-dependent cytotoxicity. These
results suggest that NNK may be one of the cigarette smoke components responsible for the reduction of pulmonary cytotoxicity.
Thus, NNK may have a double pro-carcinogenic effect by contributing to DNA adduct formation and inhibiting AM cytotoxicity
against tumoral cells. 相似文献
103.
Agoston GE Shah JH Lavallee TM Zhan X Pribluda VS Treston AM 《Bioorganic & medicinal chemistry》2007,15(24):7524-7537
A series of 16-modified 2-methoxyestradiol analogs were synthesized and evaluated for antiproliferative activity toward HUVEC and MDA-MB-231 cells, and for susceptibility to conjugation. In addition, the estrogenicity of these analogs was accessed by measuring cell proliferation of the estrogen-dependent cell line MCF7 in response to compound treatment. It was observed that antiproliferative activity dropped as the size of the 16 substituent increased. Selected analogs tested in glucuronidation assays had similar rates of clearance to 2-methoxyestradiol, but had enhanced clearance in sulfonate conjugation assays. 相似文献
104.
K. A. Conrad 《Biocontrol Science and Technology》2007,17(3):303-311
In classical weed biological control, assessing weed response to simulated herbivory is one option to assist in the prioritization of available agents and prediction of their potential efficacy. Previously reported simulated herbivory studies suggested that a specialist herbivore in the leaf-feeding guild is desirable as an effective biological control agent for cat's claw creeper Macfadyena unguis-cati (Bignoniaceae), an environmental weed that is currently a target for biological control. In this study, we tested (i) whether the results from glasshouse-based simulated herbivory can be used to prioritise potential biological control agents by evaluating the impact of a leaf-sucking tingid bug Carvalhotingis visenda (Drake & Hambleton) (Hemiptera: Tingidae) in quarantine; and (ii) the likely effectiveness of low- and high-densities of the leaf-sucking tingid after its release in the field. The results suggest that a single generation of C. visenda has the potential to reduce leaf chlorophyll content significantly, resulting in reduced plant height and leaf biomass. However, the impact of one generation of tingid herbivory on below-ground plant components, including the roots and tuber size and biomass, were not significant. These findings are consistent with results obtained from a simulated herbivory trial, highlighting the potential role of simulated herbivory studies in agent prioritisation. 相似文献
105.
Ke T Jeong EK Wang X Feng Y Parker DL Lu ZR 《International journal of nanomedicine》2007,2(2):191-199
Cyclic Arg-Gly-Asp-D-Phe-Lys [c(RGDfK)] targeted poly(L-glutamic acid) (PGA)-(Gd-DO3A) conjugate with a biodegradable cystamine spacer was prepared and evaluated for in vivo detection of an angiogenesis biomarker, alpha(v)beta3 integrin, in neoplastic tissues with T1 mapping, a quantitative magnetic resonance imaging (MRI) technique. The binding activity of the c(RGDfK) containing conjugate was investigated using in vitro vitronectin assay with human prostate carcinoma DU145 cell line and Kaposi's sarcoma SLK cell line. The peptide c(RGDfK) and PGA-cystamine-(Gd-DO3A) conjugate were used as controls. The binding affinity of polymer bound c(RGDfK) was slightly lower than free c(RGDfK) peptide. The RGD targeted conjugate had higher binding affinity to the DU145 cells than the SLK cells, which was consistent to free c(RGDfK). The imaging of alpha(v)beta3 integrin with targeted PGA-cystamine-(Gd-DO3A) was evaluated in nude mice bearing DU145 and SLK xenografts at a dose of 5 micromol-Gd/kg. The targeted conjugate demonstrated higher in vivo binding affinity to the DU145 xenografts than the SLK xenografts, resulting in a significant decrease of T1 values of water protons in the periphery of the DU145 tumors as shown in the MR T1 maps. No significant decrease of T1 values was observed in the SLK tumor with the targeted conjugate and in both tumors with the non-targeted conjugate. The targeted polymeric Gd(III) chelate conjugate with a degradable spacer has the potential to be a new paradigm for safe and effective probes in molecular imaging with quantitative MR T1 mapping. 相似文献
106.
Lai F Sinico C De Logu A Zaru M Müller RH Fadda AM 《International journal of nanomedicine》2007,2(3):419-425
The effect of SLN incorporation on transdermal delivery and in vitro antiherpetic activity of Artemisia arborescens essential oil was investigated. Two different SLN formulations were prepared using the hot-pressure homogenization technique, Compritol 888 ATO as lipid, and Poloxamer 188 and Miranol Ultra C32 as surfactants. Formulations were examined for their stability for two years by monitoring average size distribution and zeta potential values. The antiviral activity of free and SLN incorporated essential oil was tested in vitro against Herpes Simplex Virus-1 (HSV-1) by a quantitative tetrazolium-based colorimetric method (MTT), while the effects of essential oil incorporation into SLN on both the permeation through and the accumulation into the skin strata was investigated by using in vitro diffusion experiments through newborn pig skin and an almond oil Artemisia essential oil solution as a control. Results showed that both SLN formulations were able to entrap the essential oil in high yields and that the mean particle size increased only slightly after two years of storage, indicating a high physical stability. In vitro antiviral assays showed that SLN incorporation did not affect the essential oil antiherpetic activity. The in vitro skin permeation experiments demonstrated the capability of SLN of greatly improving the oil accumulation into the skin, while oil permeation occurred only when the oil was delivered from the control solution. 相似文献
107.
Kim D Lee JS Park YK Kim JF Jeong H Oh TK Kim BS Lee CH 《Journal of applied microbiology》2007,102(4):937-944
AIMS: Hahella chejuensis KCTC 2396 produces red pigments, showing antibacterial and algicidal activities. The main red-coloured metabolite of the pigments was identified as antibiotic prodigiosin. With the expectation that the red pigments are a mixture of a series of close relatives, the aim of the present study is to detect new antibiotic prodigiosin analogues and to analyse the biosynthetic pattern for prodiginines in KCTC 2396. METHODS AND RESULTS: Except prodigiosin, the other constituents in the red pigments were confirmed as well-known dipyrrolyldipyrromethene prodigiosin, norprodigiosin, and undecylprodiginine. Additionally, four new prodigiosin analogues, each of which was distinguished from prodigiosin (C(5)), according to differences in alkyl chain length (C(3)-C(7)), were detected in small quantities by liquid chromatography mass spectrometry/mass spectrometry spectroscopy. Owing to the presence of a cytotoxic methoxy group, it is expected that all the new prodigiosin analogues are bioactive. CONCLUSIONS: Four characterized prodiginines, including prodigiosin and four new prodigiosin analogues are produced in different ratio in KCTC 2396. All of the prodiginines possess a common linear tripyrrolyl structure and a cytotoxic methoxy group. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows for the first time that KCTC 2396 is able to produce antibiotic prodigiosin, undecylprodiginine and new prodigiosin analogues in a mixture of pigments. It is also shown that KCTC 2396 possesses a novel system for the simultaneous production of multiple prodiginines in a single micro-organism. 相似文献
108.
109.
N. Ledn A. Casac D. Remirez A. Gonzlez J. Cruz R. Gonzlez A. Capote Z. Toln E. Rojas V.J. Rodríguez N. Merino S. Rodríguez O. Ancheta M.C. Cano 《Phytomedicine》2007,14(10):690-695
A mixture of fatty acids obtained from sugar cane (Saccharum officinarum L.) wax oil (FAM), in which the main constituents are palmitic, oleic, linoleic, and linolenic acids, was evaluated in two models of inflammation: zymosan-induced arthritis and in the tail test for psoriasis, both on mice. In the first model, FAM significantly reduced zymozan-induced increase of beta glucuronidase (DE(50) 90+/-7 mg/kg). Histopathological studies showed inhibition in cellular infiltration and reduction of synovial hyperplasia and synovitis, whereas in the second test, histopathological and ultrastructural studies showed that topical application of FAM induced orthokeratosis with the presence of keratohyalin granules in the previously parakeratotic adult mouse tail, and without effects on epidermal thickness. The ED(50) of FAM in this model was 155+/-10 mg. The results of our studies showed that topical application of FAM exerts an important anti-inflammatory activity in both tests without evidence of irritant effects. The anti-inflamatory effects exerted by FAM may be due to its inhibitory effects on arachidonic acid metabolism. To our knowledge, this is the first report on the anti-inflammatory effect of sugar cane by-products in experimental models of arthritis and psoriasis. 相似文献
110.
Hélène Bertrand Sophie Bombard David Monchaud Marie-Paule Teulade-Fichou 《Journal of biological inorganic chemistry》2007,12(7):1003-1014
A novel platinum–quinacridine hybrid, comprising a monofunctional Pt moiety and a G-quadruplex ligand (mono-para-quinacridine or MPQ), has been synthesized and shown to interact with quadruplex DNA via a dual noncovalent/covalent binding
mode. Denaturing gel electrophoresis was used to separate the various platination products of 22AG (an oligonucleotide that
mimics the human telomeric repeat) by Pt-MPQ, and it was shown that two platinated adducts are highly stable quadruplex structures.
Dimethylsulfate/piperidine treatment and 3′-exonuclease digestion of the isolated adducts allowed us to precisely determine
the platination pattern of 22AG by Pt-MPQ, which displays three main sites G2, G10 and G22. Data presented herein support
the hypothesis that Pt-MPQ traps preferentially the antiparallel structure of the 22AG quadruplex. Finally, the kinetics of
Pt-MPQ platination using a construct containing both quadruplex DNA and a duplex DNA parts provide the first insights into
the Pt-MPQ preference for quadruplex DNA over duplex DNA. 相似文献