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91.
Andersson BE Lundstedt S Tornberg K Schnürer Y Oberg LG Mattiasson B 《Environmental toxicology and chemistry / SETAC》2003,22(6):1238-1243
Soil artificially contaminated with fluorene, phenanthrene, pyrene, and benz[a]anthracene was inoculated with the wood-rotting fungi Plrurotus ostreatus and Antrodia vaillantii. During 12 weeks of incubation, polycyclic aromatic hydrocarbon (PAH) degradation and the formation of persistent degradation products were monitored by chemical analysis. In addition, the effect on the indigenous soil bacteria was studied by plate count techniques and by measuring the concentration of bacteria-specific phospholipid fatty acids (PLFAs). In both soils inoculated with fungi, the PAH degradation was enhanced compared to the control soil without fungi. The white-rot fungus P. ostreatus accelerated the degradation rate radically the first weeks, while the effect of the brown-rot fungus was more pronounced at later stages during the 12-week study. In a soil with no amendments, the final degradation result was similar to that in the soil with added fungi, although the degradation pattern for the individual PAHs was different. Furthermore, the degradation by P. ostreatus was accompanied by an accumulation of PAH metabolites, that is, 9-fluorenone, benz[a]anthracene-7,12-dione, and two compounds identified as 4-hydroxy-9-fluorenone and 4-oxapyrene-5-one, that was not seen in the other soils. The inoculation with the white-rot fungus also had a large negative effect on the indigenous soil bacteria. This could be an important drawback of using the white-rot fungus P. ostreatus in soil bioremediation since a sequential fungal-bacterial degradation probably is needed for a complete degradation of PAHs in soil. In the soil inoculated with A. vaillantii, on the other hand, no metabolites accumulated, and no negative effects were observed on the indigenous microorganisms. 相似文献
92.
Severe hepatic adverse drug reactions have been occasionally reported in the literature for the selective serotonin reuptake inhibitors (SSRIs), venlafaxine and nefazodone. In addition, a few case reports have suggested a possible association between SSRI treatment and pancreatitis. To further investigate this issue, a Bayesian confidence propagation neural network (BCPNN) method was applied on the World Health Organization database of adverse drug reactions. This method identifies whether a drug/adverse drug reaction combination is reported more frequently to the database than expected on the basis of chance alone compared to general reporting in the database. A statistically significant unexpected high number of reports were found for nefazodone and hepatic injury, relative to the generality of the dataset but, for the other drug/adverse drug reaction combinations, no such association was found. The nefazodone finding is in accordance with data from other publications, suggesting that the risk of hepatic injury is increased. However, because of the nature of the BCPNN, the negative findings do not necessarily prove that there is no excess risk for hepatic injury/pancreatitis during treatment with drugs other than nefazodone. Further studies are required using alternative methodologies to demonstrate whether the selective serotonin reuptake inhibitors or venlafaxine may cause hepatic injury or pancreatitis. 相似文献
93.
94.
Jacobsson H Bremmer S Larsson SA 《European journal of nuclear medicine and molecular imaging》2003,30(8):1169-1172
On single-photon emission tomography (SPET) examinations with indium-111 pentetreotide, we have often observed a small "hot" spot close to the upper portion of the left kidney. While it was initially believed that this represented a tumour in the tail of the pancreas or in the left adrenal, we now understand that it represents normal adrenal uptake. Since the adrenals have not been described as normally visualised, this uptake may interfere with the interpretation of the examination. We have studied how often the normal adrenals are visualised at such examinations. One hundred consecutive clinical (111)In-pentetreotide examinations in adults including SPET of the abdomen and with normal findings were studied. All examinations with a hot spot attributable to the adrenals were, when available, compared with computed tomography (CT) or magnetic resonance imaging (MRI) of the abdomen performed on clinical grounds within 3 months before or at any time after the scintigraphy. In 11 patients both adrenals were visualised. In 27 patients only the left and in one only the right adrenal was visualised. CT or MRI examinations were available for comparison in 25 of these 39 patients. Two of these showed a pathological finding in the left adrenal. A conservative interpretation is that the normal adrenal is visualised on one or both sides in at least one-quarter of adults at SPET examination with (111)In-pentetreotide. 相似文献
95.
Ototoxicity,nephrotoxicity and pharmacokinetics of cisplatin and its monohydrated complex in the guinea pig 总被引:5,自引:0,他引:5
Ekborn A Lindberg A Laurell G Wallin I Eksborg S Ehrsson H 《Cancer chemotherapy and pharmacology》2003,51(1):36-42
PURPOSE: To evaluate and compare the ototoxicity and nephrotoxicity of cisplatin and cis-diammineaquachloroplatinum(II) ion (monohydrated complex of cisplatin, MHC, formed in vivo by hydrolysis of cisplatin) after their separate administration to guinea pigs. METHODS: A dose of 4 mg/kg body weight of MHC was deemed suitable for the toxicity evaluation after dose titration. Electrophysiological hearing thresholds (auditory brainstem response, ABR), plasma creatinine and weight were measured in three groups of animals before and after receiving MHC 4 mg/kg (0.0141 mmol/kg), cisplatin 4.24 mg/kg (0.0141 mmol/kg, i.e. equimolar dose) or cisplatin 8 mg/kg (0.0267 mmol/kg) as an i.v. bolus injection. Cisplatin and MHC were analysed using liquid chromatography with post-column derivatization. RESULTS: Administration of MHC 4 mg/kg caused a moderate ABR threshold shift, a significant increase in creatinine and a significant weight loss, changes similar to those seen after administration of cisplatin 8 mg/kg. Animals given cisplatin 4.24 mg/kg had a slight increase in creatinine, but had no ABR threshold shift and gained weight during the experiment. The pharmacokinetic parameters of cisplatin and MHC were estimated after administration of cisplatin 4.24 mg/kg and MHC 4 mg/kg. The area under the blood-ultrafiltrate concentration versus time curve (AUC) for cisplatin after administration of MHC 4 mg/kg was 23% (56+/-5.0 micro g.min.ml(-1)) (means+/-SD) of that after administration of cisplatin 4.24 mg/kg (240+/-25 micro g.min.ml(-1)). The AUC for MHC after administration of cisplatin 4.24 mg/kg was 20% (30+/-4.9 micro g.min.ml(-1)) of that after administration of MHC 4 mg/kg (149+/-26 micro g.min.ml(-1)). CONCLUSIONS: MHC 4 mg/kg causes ototoxicity, nephrotoxicity and weight loss when administered to guinea pigs. The toxic effects were similar to those seen after administration of cisplatin 8 mg/kg and higher than those seen after administration of cisplatin 4.24 mg/kg. 相似文献
96.
Pehrsson SK Eriksson MJ Lentell JC Bowald S 《Scandinavian cardiovascular journal : SCJ》2003,37(4):235-239
OBJECTIVE: A new tri-leaflet mechanical heart valve made of titanium was inserted in the mitral position to evaluate early results. METHODS AND RESULTS: Five sheep were followed between 3 and 6 months (mean 4.7 months) and performed very well clinically during the follow-up period. In three of five animals a minor para-valvular leakage without hemodynamic importance was observed. The invasive pressure measurements at the end of follow-up revealed only minor transvalvular pressure differences between 1 and 4 mmHg (mean 2.4 mmHg). Similar results were obtained by echo-Doppler technique. Histological examination of the tissue around the valve showed no signs of foreign body reaction or chronic inflammatory reaction. CONCLUSION: This new tri-leaflet heart valve has shown an excellent hemodynamic performance and good tissue compatibility, and therefore may be an alternative to other currently used valve prostheses. 相似文献
97.
Holmgren D Redfors S Rydberg A Wåhlander H 《Clinical physiology and functional imaging》2003,23(2):120-122
We report a case of recurrent syncope in association with moderate ventricular dysfunction and mild AV-valve regurgitation in an 18-year-old girl, 4 years after she underwent total cavopulmonary connection surgery. Cardiac catheterization revealed a transpulmonary gradient of 1-2 mmHg. During exercise, a dramatic fall in blood pressure and blood oxygenation was observed, paralleled by an increase in heart rate and central venous pressure. Although a slight increase in pulmonary vascular resistance could not be excluded, the reaction was interpreted in terms of an extremely low transpulmonary gradient in association with ventricular dysfunction. Five months after heart transplantation, the patient has been completely free from syncope. Fontan circulation usually involves a delicate haemodynamic situation which may necessitate haemodynamic re-evaluations, including dynamic measurements of the central venous pressure during exercise. Also a moderate ventricular dysfunction may result in compromised pulmonary circulation which in turn may lead to syncope during exercise as a result of insufficient systemic circulation. 相似文献
98.
99.
Olav Spigset Tonny Andersen Staffan H gg Tom Mj rndal 《European neuropsychopharmacology》1999,9(6):469-473
Some evidence exists to suggest that serotonin 5-HT2A receptor function is altered in anorexia nervosa and bulimia nervosa. In order to further investigate the 5-HT2A receptor in eating disorders, platelet [3H]lysergic acid diethylamide ([3H]LSD) binding was studied in ten patients with anorexia nervosa, 23 patients with bulimia nervosa and 33 healthy controls. At admission, Bmax for platelet [3H]LSD binding was significantly higher both in the anorexia nervosa group (30.6±4.2 fmol/mg protein; mean±S.D.) and in the bulimia nervosa group (30.8±7.6 fmol/mg protein) than in the control group (23.5 ±6.3 fmol/mg protein; p=0.01 and p=0.003, respectively). Kd was borderline significantly higher among anorexics (median 1.45 nM) and significantly higher among bulimics (median 1.66 nM) than among controls (median 0.95 nM; p=0.05 and 0.003, respectively). The Global Assessment of Functioning score and the body mass index were both significantly negatively correlated to Kd (r=−0.40; p=0.03 and r=−0.41 p=0.03, respectively), but not to Bmax. The present study indicates that patients with anorexia nervosa as well as patients with bulimia nervosa have an enhanced 5-HT2A receptor binding and provides further evidence for a serotonergic dysfunction in eating disorders. 相似文献
100.
Bertil M. Philipson M.D. Ph.D. Thomas Höckenström M.D. Staffan Åkerlund M.D. 《World journal of surgery》1987,11(6):790-797
Segments of ileum are often used as conduits in connection with supravesicle diversion or sometimes for bladder augmentation. This implies that ileal mucosa will be deprived of the normal intestinal contents and instead exposed to urine. Reports on the morphological consequences of exposure to urine have been contradictory. Either normal structure or various degrees of atrophy have been reported. For this reason, an investigation was designed for systematic follow-up of effects on the ileal mucosa in patients with continent ileal reservoirs for urinary collection (Kock pouch). These investigations showed that there were significant changes in villous height, crypt depth, and number of goblet cells starting early after construction and leading to complete atrophy in certain areas. Electron microscopy and enzyme histochemistry also showed, in the epithelial cells, that there was a reduction in the number of cell organelles and microvillous units, and also decreased metabolic activity. Reductions were also recorded in studies of net transport of both water and electrolytes across the mucosa of the ileal reservoir used for urinary collection.From the clinical point of view, the adaptive changes recorded in the investigations of ileal mucosa exposed to urine are advantageous, since the risk of metabolic disturbances due to reabsorption of urine is diminished.
Supported by grants from the Swedish Medical Research Council (no. 00577). 相似文献
Resumen Segmentos de íleo son frecuentemente utilizados como canal urinario en casos de desviación supravesical o, algunas veces, para agrandamiento de le vejiga. Esto quiere decir que la mucosa ileal, en vez de recibir el contenido intestinal normal, queda expuesta a la orina. Los informes sobre las consecuencias morfológicas de la exposición a la orina han sido contradictorios; se ha informado tanto la presencia de una estructura normal como de atrofia. Por tal razón se diseñó una investigación para el seguimiento sistemático de los efectos sobre la mucosa ileal en pacientes con reservorios urinarios ileales continentes (bolsa de Kock). La investigación demostró que se presentan cambios de significación en cuanto a altura de las vellosidades, profundidad de las criptas, y número de células caliceales, comenzando muy temprano después de la creación de la bolsa y dando lugar a atrofia completa en ciertas áreas. La microscopía electrónica y la histoquímica enzimática también demostraron que en las células epiteliales había reducción en el número de los organelos, las unidades microvellosas, y una reducida actividad metabólica. También se registraron reducciones en los estudios de transporte neto tanto de agua como de electrolitos a través de la mucosa del reservorio ileal utilizado para la recolección de la orina.Desde el punto de vista clínico, los cambios de adaptación registrados en la investigación realizada sobre la mucosa ileal expuesta a orina son ventajosos, puesto que disminuyen el riesgo de alteraciones metabólicas producidas por la reabsorción de la orina.
Résumé Des segments de l'iléon sont souvent employés pour augmenter la capacité de la vessie ou pour la remplacer. Ce fait implique que la muqueuse iléale exempte du contenu intestinal normal est exposée à l'action de l'urine. Des études sur les conséquences morphologiques dues à ce facteur ont abouti à des résultats contradictoires. Tantôt la structure a été considérée comme normale, tantôt des degrés divers d'atrophie ont été constatés. Pour cette raison une étude a été entreprise pour établir les effets secondaires de l'urine sur la muqueuse de l'iléon, en particulier après la constitution d'une néo-vessie selon la technique de Kock. Cette étude a montré des modifications significatives de la hauteur des villosités, de la profondeur des cryptes, du nombre des cellules à gobelet, modifications débutant rapidement après la confection du réservoir iléal et aboutissent à une atrophie complète en certaines zones. La microscopie électronique et l'histochimie enzymatique ont montré qu'au niveau des cellules épithéliales se manifestent aussi une réduction du nombre des organelles cellulaires, des unités microvilleuses, et de l'activité métabolique. Une réduction du transport à la fois de l'eau et des électrolytes au travers de la muqueuse iléale du réservoir a été également constatée.D'un point de vue clinique, les phénomènes d'adaptation constatées au niveau de la muqueuse iléale soumise au contact de l'urine ont pour avantage de réduire les risques d'altérations métaboliques dues à la réabsorption de l'urine.
Supported by grants from the Swedish Medical Research Council (no. 00577). 相似文献