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31.
Hemoperfusion study with carbamazepine in vitro 总被引:2,自引:0,他引:2
Derzsiová K Mydlík M Petríková V 《The International journal of artificial organs》1999,22(11):730-733
Sorption efficacy of active charcoal, Amberlite XAD-2 and Amberlite XAD-4 in hemoperfusion with carbamazepine was investigated in vitro. Authors carried out 15 hemoperfusions with carbamazepine in a closed system using the above mentioned sorbents; The perfusion solution used was 3,000 ml of 0.9% NaCl. The carbamazepine concentration in the solution was 52.5+/-3.0 mg/L. In addition, two in vitro hemoperfusions with carbamazepine using Amberlite XAD-2 sorbent and 1.500 ml of human plasma as a perfusion solution, were also performed. The concentration of carbamazepine in plasma was 50.4+/-1.2 mg/L. Individual hemoperfusions lasted 5 hours. Zero values of carbamazepine were achieved after 120 min of Amberlite XAD-2 or Amberlite XAD-4 hemoperfusion in 0.9% NaCl and after 240 min of hemoperfusion in human plasma. The results gathered suggest that the most effective in vitro hemoperfusion with carbamazepine was obtained with Amberlite XAD-2 or Amberlite XAD-4 and the least effective was with active charcoal. The authors recommend the use of hemoperfusion with Amberlite XAD-2 or Amberlite XAD-4 for acute intoxications with carbamazepine in humans. In addition, authors successfully performed 5-hour hemoperfusion using Amberlite XAD-4 in vivo, in an 18-year-old girl, who suffered from acute carbamazepine intoxication after a suicidal attempt. This treatment led to the rapid survival. 相似文献
32.
W. von der Hude M. Scheutwinkel-Reich R. Braun W. Dittmar 《Archives of toxicology》1985,56(4):267-271
Valepotriates are epoxide-bearing triesters of the monoterpene alcohol 4,7-dimethylcyclopenta-(c)-pyrane isolated from the roots of several Valerianacae species. They are regarded as the main tranquilizing constituents of these drugs.Although the valepotriates valtrate/isovaltrate (VAL) and dihydrovaltrate (DH-VAL) showed a strong alkylating activity against the nucleophilic agent 4-(p-nitrobenzyl)-pyridine (NBP), they were not clearly mutagenic for the strains TA98, TA100, TA1535, and TA1537 of Salmonella typhimurium or for the strains WP2 and WP2 uvrA– of Escherichia coli in the absence of a metabolic activation system (S9-mix). However, the valepotriates were mutagenic for TA100, WP2 and WP2 uvrA– at concentrations up to about 1.0 mole/plate when S9-mix was added to the test system. With more than 1 mole/plate the valepotriates were toxic in the presence of a metabolic activation system for all strains tested. The mutagenicity of the valepotriates was inversely related to the protein content of the S9-mix used. The mutagenicity and toxicity of the valepotriates could be inhibited when the S9-mix was preincubated with the esterase inhibitor paraoxon (1 mM) for 5 min before the test compounds and bacteria were added. Therefore, bioactivation of the valepotriates by an enzymatic hydrolysis of their ester groups is considered. This could be proven by activating the valepotriates with purified esterase.Parts of this paper were presented at the Congress, Fortschritte in der Arzneimittelforschung, April 17–20, 1983 in Munich 相似文献
33.
Gabriella Sistilli Veronika Kalendova Tomas Cajka Illaria Irodenko Kristina Bardova Marina Oseeva Petr Zacek Petra Kroupova Olga Horakova Karoline Lackner Amalia Gastaldelli Ondrej Kuda Jan Kopecky Martin Rossmeisl 《Nutrients》2021,13(2)
Preclinical evidence suggests that n-3 fatty acids EPA and DHA (Omega-3) supplemented as phospholipids (PLs) may be more effective than triacylglycerols (TAGs) in reducing hepatic steatosis. To further test the ability of Omega-3 PLs to alleviate liver steatosis, we used a model of exacerbated non-alcoholic fatty liver disease based on high-fat feeding at thermoneutral temperature. Male C57BL/6N mice were fed for 24 weeks a lard-based diet given either alone (LHF) or supplemented with Omega-3 (30 mg/g diet) as PLs (krill oil; ω3PL) or TAGs (Epax 3000TG concentrate; ω3TG), which had a similar total content of EPA and DHA and their ratio. Substantial levels of TAG accumulation (~250 mg/g) but relatively low inflammation/fibrosis levels were achieved in the livers of control LHF mice. Liver steatosis was reduced by >40% in the ω3PL but not ω3TG group, and plasma ALT levels were markedly reduced (by 68%) in ω3PL mice as well. Krill oil administration also improved hepatic insulin sensitivity, and its effects were associated with high plasma adiponectin levels (150% of LHF mice) along with superior bioavailability of EPA, increased content of alkaloids stachydrine and trigonelline, suppression of lipogenic gene expression, and decreased diacylglycerol levels in the liver. This study reveals that in addition to Omega-3 PLs, other constituents of krill oil, such as alkaloids, may contribute to its strong antisteatotic effects in the liver. 相似文献
34.
Vlasák Aleš Skalický Petr Mládek Arnošt Vrána Jiří Beneš Vladimír Bradáč Ondřej 《Neurosurgical review》2021,44(1):503-514
Neurosurgical Review - To assess automated volumetric analysis as a potential presurgical diagnostic tool or as a method to potentially shed light on normal pressure hydrocephalus (NPH)... 相似文献
35.
Alexander Mülsch Markus Hecker Petr I. Mordvintcev Anatoly F. Vanin Rudi Busse 《Naunyn-Schmiedeberg's archives of pharmacology》1993,347(1):92-100
Summary The molecular mechanism(s) underlying the vasodilator activity of CAS 936 (3-(cis-2,6-dimethylpiperidino)-N-(4-methoxybenzoyl)-sydnonimine) and its metabolites 3-(cis-2,6-dimethylpiperidino)-sydnonimine (C87 3754) and N-(cis-2,6-dimethylpiperidino)-N-nitroso-2-aminoacetonitril (C873786) was investigated. These compounds were tested for their relaxant activity in isolated rabbit arterial segments, activation of purified soluble guanylyl cyclase and release of nitric oxide (NO) in vitro and in vivo. C873754 and C873786 inhibited the noradrenalin-induced contraction and increased the cyclic GMP content of endothelium-denuded rabbit aortic and femoral segments, whereas CAS 936 was without effect. Similarly, both metabolites, but not CAS 936, activated purified soluble guanylyl cyclase (EC50 about 30 M) and released NO in buffered aqueous solutions, as detected by electron spin resonance (esr) spectrometry. Both in vitro and in vivo an accumulation of NO was detected by esr spectrometry in vascular tissues exposed to the metabolites of CAS 936, whereas a significant release of NO from CAS 936 was only detected in the isolated rabbit liver, but not in vascular tissue. It is conceivable, therefore, that the metabolites of CAS 936 appearing in the systemic circulation after hepatic biotransformation induce vasodilatation by release of NO and activation of soluble guanylyl cyclase in vascular smooth muscle. Moreover, the activation of soluble guanylyl cyclase in vitro by the metabolites of CAS 936 was significantly enhanced by co-incubation with certain particulate fractions from bovine aortic endothelial and smooth muscle cells. Thus, an enzymic release of NO from these metabolites in addition to their spontaneous decomposition may play a significant role for their vasodilator activity in vivo.Correspondence to A. Mülsch at the above address 相似文献
36.
Ivan Karel Bohdana Kalvodová Martin Filipec Eva Boháčová Petr Soucek Ctibor Povýšil Jiří Vacík Marie Tlusťáková 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1997,235(3):186-189
Background: The highly swelling poly(glycerol monomethacrylate) gel (polyGLYMA) and hydrophilic polymer poly(triethylenglycol monomethacrylate (polyTEGMA) were tested as potential viscoelastics for intraopertive use in anterior segment surgery. Methods: PolyGLYMA was implanted into the anterior chamber in 5 rabbits, and 40% polyTEGMA in 16 rabbits. The eyes were enucleated 1 week to 3 months after the operation. The corneal endothelium was examined with specular microscopy, and then the whole eye histopathologically. Results: In all eyes of the polyGLYMA group, the clinical findings were characterized by a marked ciliary injection and severe secondary glaucoma, and the histologic ones by a marked inflammatory infiltration and thickening of Descemet's membrane in the anterior chamber angle. Specular microscopy revealed a decrease in the endothelial cell density and polymorphism of the endothelial cells. In the polyTEGMA group, the anterior segment and the fundus were physiologic all the time, and specular microscopy and histologic findings showed no degenerative and/or inflammatory changes. Conclusions: PolyGLYMA proved unsuitable for intracameral application in rabbits. The new polymer polyTEGMA is characterized by high biologic tolerance after its implantation into the anterior chamber of rabbits. PolyTEGMA 40% might be considered as a potential viscoelastic material in humans. 相似文献
37.
Petr J Rozinek J Vanourková Z Jílek F 《Reproduction, fertility, and development》1999,11(4-5):235-246
Calcium plays an important role in the regulation of meiotic maturation in mammalian oocytes. In the present study, mycotoxin cyclopiazonic acid (CPA), an inhibitor of calcium-dependent ATPases, was used to mobilize intracellular calcium deposits in growing pig oocytes, which had not attained full meiotic competence and in which maturation is thus spontaneously blocked at the metaphase I stage. CPA treatment significantly increased the ratio of growing oocytes that are able to overcome the spontaneously occurring metaphase I block to complete their maturation at the metaphase II stage. CPA treatment of a least 2 hours' duration is necessary to overcome the metaphase I block in growing oocytes. A similar effect upon release from the spontaneous meiotic block at the metaphase I stage was observed after treatment of growing pig oocytes with thapsigargin, another inhibitor of endogenous calcium-dependent ATPases. Numerous calcium deposits in vacuoles, the mitochondria and on the surface of yolk granules in growing pig oocytes were observed. CPA treatment is able to mobilize calcium from the mitochondria, but deposits in vacuoles and deposits on the surface of yolk granules seem to remain intact after CPA treatment. A microinjection of heparin, which is known to bind with the inositol trisphosphate receptors, significantly decreased the ratio of CPA-treated growing oocytes overcoming the block at the metaphase I stage. This indicates that CPA might mobilize calcium in growing pig oocytes through inositol trisphosphate receptors. On the other hand, a microinjection of procaine or a microinjection of ruthenium red, both inhibitors of ryanodine receptors, did not prevent the overcoming of the metaphase I block, induced by CPA treatment. The calcium channel blocker, verapamil, significantly reduces the proportion of CPA-treated growing oocytes that overcome the metaphase I block. This indicates that the influx of calcium from extracellular sources is necessary to overcome the metaphase I block. The calmodulin inhibitors ophiobolin A and W7 also reduce the proportion of CPA-treated growing oocytes overcoming the metaphase I block. 相似文献
38.
G Liszka A Petrányi N Udvarhelyi J Demeter M Bodó I Besznyák A Ladányi P Vargha L D?bróssy 《Orvosi hetilap》1999,140(27):1533-1536
Some pathological findings and prognostic indices recorded in breast cancer cases, detected, on one hand, by a provider-initiated mammography screening program (Group 1), and, opportunistically, in self-referred symptomatic women (Group 2) on the other, are compared. In 8877 symptom-free women, aged 50-65 years, individually invited to attend the screening offered for the residents of the III., XII. and XIII. districts of Budapest, 67 cancer cases were detected (7.5 in 1000 screenees), in accordance with the cancer detection rate of the first, "prevalence" round of organised screening programmes. In the other group of 1593 symptomatic, self-referred women of the same age, 113 cancer cases were diagnosed by mammography. As far as the pathological parameters are concerned, the number of cases with invasive cancer less than 15 mm in diameter, and those with axillary nodes present was found to be significantly higher in the screened group as compared to the self-referred one (p < 0.01). In "small" cancers (i.e. less than 15 mm in diameter), no significant difference was found in the proportion of histologic grade III tumours among the two groups. In screen-detected cancers both the morphometric prognostic index (as calculated by Baak et al.) and the Nottingham Prognostic Index (NPI) proved to be more favourable, as compared to those in the self-referred group. The p-value as determined by Mann-Whithey test was 0.000003 in the screened group, and 0.000015 in the other one. These findings provide convincing evidence in support of the public health importance of provider-initiated, organised mammography screening for breast cancer, therefore, the introduction on service basis of organised breast screening into the health care system in Hungary is strongly recommended by the authors. 相似文献
39.
40.
Thomeer M Vanbeckevoort D Van Breuseghem I Petré C De Vuysere S Coenegrachts K Miserez M 《European radiology》2000,10(4):674-676
This article presents a case of appendicitis 7 years after open appendectomy. Together with the apparent CT findings we discuss
the current literature of this issue.
Received: 21 April 1999; Revised: 11 August 1999; Accepted: 13 August 1999 相似文献