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991.
Long‐term recurrence of soft tissue sarcomas: Prognostic factors and implications for prolonged follow‐up
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Maud Toulmonde MD Axel Le Cesne MD Jean Mendiboure MSc Jean‐Yves Blay MD PhD Sophie Piperno‐Neumann MD Christine Chevreau MD Corinne Delcambre MD Nicolas Penel MD PhD Philippe Terrier MD Dominique Ranchère‐Vince MD Marick Lae MD Sophie Le Guellec MD Jean‐Jacques Michels MD Yves‐Marie Robin MD Carine Bellera PhD Antoine Italiano MD PhD 《Cancer》2014,120(19):3003-3006
992.
Dual-label time-resolved fluoroimmunoassay for simultaneous detection of aflatoxin B1 and ochratoxin A 总被引:3,自引:0,他引:3
Biao Huang Hualong Xiao Jue Zhang Lianfen Zhang Hailin Yang Yi Zhang Jian Jin 《Archives of toxicology》2009,83(6):619-624
A dual-label time-resolved fluoroimmunoassay (TRFIA) for simultaneous quantification of aflatoxin B1 (AFB1) and ochratoxin
A (OTA) is described. For this, microtitration wells were coated with AFB1-horse radish peroxidase (HRP) and OTA–bovine serum
albumin. The standards and samples were loaded on the coated plates, and diluted antibodies and Eu3+- and Sm3+-labeled IgG were then added. Our results showed that the sensitivity of TRFIA for AFB1 was 0.02 μg/L (range 0.02–100 μg/L).
The intra- and inter-batch coefficient of variation (CV) was 3.2 and 7.3%, respectively, and the average recovery rate was
88.1%. On the other hand, the sensitivity of OTA was 0.05 μg/L (range 0.05–50 μg/L), the intra- and inter-batch CV was 2.9
and 7.9%, respectively, and the average recovery rate was 89.9%. In the AFB1/OTA–TRFIA, AFB1 and OTA did not mutually interfere.
The correlation coefficients between the dual-label AFB1/OTA–TRFIA and the single-label AFB1–TRFIA or OTA–TRFIA were 0.972
and 0.981, respectively, indicating that the results were consistent. Our study suggests that AFB1/OTA–TRFIA allows the simultaneous
detection of AFB1 and OTA; is a simple, fast, and economic method for screening large quantities of samples, and has good
prospects of application. 相似文献
993.
Sreekanth Thota Srujana Vallala Rajeshwar Yerra Daniel Alencar Rodrigues Eliezer J. Barreiro 《Medicinal chemistry research》2016,25(10):2127-2132
The synthesis and characterization of ruthenium complexes (Ru-1–Ru-6) of the type [Ru(R)2(K)]2+ (where R?=?1,10-phenanthroline/2,2′-bipyridyl and K?=?acetyl coumarin-inh, pyrazole-tch, acetyl coumarin-tsz, are described. These ligands form bidentate octahedral ruthenium complexes. The in vitro cytotoxic activities of the complexes measurement against the human cancer T-lymphocyte cell lines. In vitro evaluation of these title complexes revealed cytotoxicity from 0.34 to 1.4?µg/mL against CEM, 0.28 to 1.8?µg/mL against L1210, 0.44 to 2.5?µg/mL against Molt4/C8, 0.98 to 1.6?µg/mL against HL60, and 0.66 to 1.4?µg/mL against BEL7402. Ruthenium complexes Ru-5 & Ru-6 showed that quite significant anticancer activities over standard drugs. 相似文献
994.
Rationale and objective Although many contingencies operating in the natural environment include continuous dimensions of responses and reinforcers,
previous studies of drug self-administration have almost exclusively used discrete dimensions of responses (e.g., a lever
press) and reinforcers (e.g., 1.0 mg/kg/injection cocaine). Therefore, the present study provides an initial examination under
experimental conditions with both responses and reinforcers measured along continuous dimensions.
Materials and methods Cocaine-maintained responding was studied in rats under a novel, hold-down schedule of reinforcement wherein the duration
of the response was directly related to the magnitude of the reinforcer. These conditions were established by activating the
syringe pump when the lever was pressed down and turning the pump off when the lever was released. The concentration of cocaine
available in the syringe was varied across sessions.
Results Cocaine self-administration was readily maintained under these conditions and remained stable across sessions. Responding
was concentration dependent, with the number of responses and total duration of the response inversely related to concentration,
and overall session intake of cocaine was stable across concentrations. In general, the duration of the responses were less
than 0.5 s and did not vary as a function of concentration.
Conclusions Stability of responding under these schedule conditions was acquired quickly. This schedule of reinforcement may be useful
for comparing across drug classes, can be extended for use with other types of responses and reinforcers, and may be more
representative of the natural world where response-reinforcer contingencies are more likely to be experienced along continuous,
rather than discrete, dimensions.
Drake Morgan and Yu Liu contributed equally to this publication. 相似文献
995.
Kamalneet Kaur Vinod Kumar Vikas Beniwal Vikas Kumar Neeraj Kumar Vishal Sharma Sundeep Jaglan 《Medicinal chemistry research》2016,25(10):2237-2249
In search of a new class of biologically active agents, some novel oxazolidinone-thiazole hybrids 4a–m have been synthesized and characterized on the basis of a combined use of infrared, NMR (1H, 13C) spectroscopy, mass spectrometry and elemental analysis. All compounds were evaluated for their antimicrobial, antioxidant and ultraviolet mediated DNA damage protective activity. Among the series, compound 4i emerged as the most potent antimicrobial agent, particularly, against Bacillus subtilis, Candida albicans and Saccharomyces cerevisiae in comparison to the standard drugs, Ciprofloxacin (antibacterial) and Amphotericin-B (antifungal). Other promising antimicrobial agents including the compounds 4f–h. In addition, all compounds 4a–m were found to show very high DNA damage protecting ability under ultraviolet irradiation. The antioxidant study revealed that the compounds 4d and 4j were found as the most potent antioxidants as compared to ascorbic acid, a reference compound considered in the study. 相似文献
996.
Woo JS 《Archives of pharmacal research》2007,30(6):778-784
Granisetron is a selective 5-HT3 receptor antagonist that is used therapeutically for the prevention of vomiting and nausea associated with emetogenic cancer chemotherapy. Although forms of the drug are commercially available for intravenous and oral dosage, there is a need for intranasal delivery formulations in specific patient populations in which the use of these dosage forms may be unfeasible and/or inconvenient. A rapid and specific high-performance liq uid chromatography method with mass spectrometric detection (LC-MS) was developed and validated for the analysis of granisetron in plasma after nasal administration in rats. Granisetron was separated in a reverse-phase C-18 column without interference from other components of plasma. This method involves a rapid assay for the determination of granisetron in a small volume of plasma with a run time of 12 min using ondansetron as an internal standard. Data were acquired in the electrospray ionization (ESI) mode with positive ion detection and application of single ion recording (SIR). Granisetron and ondansetron were detected at m/z values of 313.2 and 294.2, respectively. The method described was found to be suitable for the analysis of all samples collected during preclinical pharmacokinetic investigations of granisetron in rats after nasal administration. To date, the first pharmacokinetic study after intranasal administration of granisetron was performed and some pharmacokinetic parameters were presented in this paper. Granisetron was found to be well absorbed through nasal route and the bioavailability of this drug following nasal administration was comparable with that of intravenous administration. 相似文献
997.
Ali Najafi Ehsan Motaghi Mohammad Javad Hosseini Masoumeh Ghasemi-Pirbaluti 《Inflammopharmacology》2017,25(1):137-145
Ulcerative colitis is a chronic recurrent disease with incomplete treatment options. The current article evaluated the effect of sodium valproate on acetic acid-induced ulcerative colitis in rats. Rats were randomly distributed into six groups including Sham group, colitis control group, sodium valproate treatment groups (50, 100 and 300 mg/kg, i.p.) and dexamethasone-treatment group. Dexamethasone was used as a reference drug. Colitis was induced by intracolonic instillation of 2 mL of 3% acetic acid solution. The efficacy of sodium valproate was evaluated by macroscopical and histopathological scoring systems, hematocrit measurement as well as biochemical analysis including myeloperoxidase (MPO) and pro-inflammatory cytokines assessment. Sodium valproate, particularly with doses of 100 and 300 mg/kg significantly improved weight loss, and macroscopic damage, reduced ulcer area, colon weight, microscopic colitis index and elevated hematocrit level. Biochemical experiments showed elevated levels of colonic MPO activity, interleukin 1β (IL-1β), interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α) in colitis control group. Treatment with sodium valproate at the doses of 100 and 300 mg/Kg) decreased the MPO activity and colonic concentrations of IL-1β, IL-6 and TNF-α. The results provide evidence that sodium valproate has a protective effect in acetic acid-induced ulcerative colitis which might be due to its anti-inflammatory activities, and it may be useful in patients with ulcerative colitis. 相似文献
998.
999.
1000.
Sequential effects of cadmium on genotoxicity and lipoperoxidation in <Emphasis Type="Italic">Vicia faba</Emphasis> roots 总被引:1,自引:0,他引:1
Kinetics of stress responses to Cd exposure (50, 100 and 200 μM) expanding from 12 to 48 h were studied in roots of hydroponically
cultivated-Vicia faba seedlings. The heavy metal induced toxicity symptoms and growth arrest of Vicia roots gradually to the Cd concentration and duration of the treatment. The intracellular oxidative stress was evaluated with
the H2O2 production. The H2O2 content increased gradually with the sequestered Cd and root growth inhibition. Lipid peroxidation—evidenced by malondialdehyde
(MDA) content and Evans blue uptake—and genotoxicity—evidenced by mitotic index (MI) and micronuclei (MCN) values—were concomitantly
investigated in root tips. By 12 h, root meristematic cells lost 15% of their mitotic activity under 50 or 100 μM Cd treatment
and 50% under 200 μM Cd treatment and led cells with MCN, while the MDA content and Evans blue absorption were not affected.
The loss of membrane integrity occurred subsequently by 24 h. The increase in MDA content in root cells treated with 50, 100
and 200 μM Cd was significantly higher than the control. By 48 h, the MDA content increased 134, 178 or 208% in root cells
treated with 50, 100 and 200 μM Cd, respectively. The Evans blue absorption was also affected by 24 h in roots when treated
with 200 μM Cd and gradually increase by 48 h with the Cd concentration of the treatment. The decrease of mitotic activity
triggered by 12 h was even higher by 24 h and the MI reduced to 44, 56 or 80% compared to the control in the three different
Cd concentrations tested. The different kinetics of early in vivo physiological and cytogenetic responses to Cd might be relevant
to the characterization of its toxicity mechanisms in disrupting primarily the mitosis process. 相似文献