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1.
Isabelle Durieu Evelyne Vericel Daniel Guichardant Hubert Roth Jean-Paul Steghens Jocelyne Drai Raphaele Nove Josserand Eric Fontaine Michel Lagarde Gabriel Bellon 《Journal of cystic fibrosis》2007,6(5):320-326
BACKGROUND: An imbalance in the ratio of arachidonic acid and docosahexaenoic acid (DHA) was found in cystic fibrosis (CF) affected tissues and was suggested to promote inflammation. Several studies have shown that the long chain n-3 fatty acids reduced inflammatory activity while others have highlighted prooxidant activity of DHA at high concentrations. The aim of our study was to evaluate the effects of an intravenous fish-oil emulsion enriched with n-3 FA in patients with CF on plasma and platelet FA composition and peroxidation markers. METHODS: 13 patients with CF received one IV emulsion per week of 2 mL/kg fish-oil n-3 emulsion for 12 weeks. RESULTS: There was a significant increase in 20:5 n-3 and 22:6 n-3 platelet FA composition, no variation in 20:4 n-6, a decrease in n-9. There was no variation in plasma FA composition. Specific urinary markers of lipid peroxidation derived from n-3 and n-6 showed a very high level before infusion compared with usual values in healthy subjects which was not affected by treatment. A significant weight loss and a decrease in reduced glutathione were observed in adult patients. CONCLUSIONS: The intravenous administration of n-3 FA in CF patients induced a significant modification in platelet FA composition but no modification of oxidative markers. However, the weight loss and the decreased level in reduced glutathione observed in adult patients may suggest a potential deleterious activity for some patients. Further studies are necessary to determine the optimal dose and route for long chain FA administration required to reach a potential beneficial effect. 相似文献
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Cultured human proximal tubule cell monolayers maintained on permeable supports were treated simultaneously with the aminoglycoside antibiotic, gentamicin, and poly-
-aspartic acid (PAA), an inhibitor of aminoglycoside nephrotoxicity. Following 4 days of exposure, cell monolayers were placed into Ussing chambers to allow monitoring of transepithelial electrical properties. For each of the three cell isolatation examined, aminoglycoside-induced alterations in electrogenic transport, reflected by changes in short-circuit current (Isc), as well as alterations in paracellular properties, indicated by changes in transepithelial electrical resistance (RT), were diminished in the presence of PAA. Alterations resulting from selective basolateral exposure to gentamicin were unchanged in the case of apically applied PAA and attenuated only when PAA acid was added basolaterally. This is the first demonstration of PAA inhibition of aminoglycoside-induced cellular alterations involving human cells. 相似文献
4.
A method to study the proliferation of human brain tumors, is presented. Non radioactive 5-Iododeoxyuridine (2.4 gr) infused over a 24 hours period is detected in situ on histologic section by an immunological technique (peroxidase-anti-peroxidase) using a specific anti-Iododeoxyuridine antibody. This exploration utilised in 45 patients is easy, reliable and harmless. All cells which enter in S phase of cellular cycle during the infusion are labelled. So the cellular kinetics of all the brain tumor cells (malignant cells, inflammatory stroma reaction cells, reactive astrocytes, endothelial and muscular cells of the vessels) are detected on the same histological section, as well as all the others proliferative cells of the body (leukocytes, primitive tumor of the metastatic brain localisation...) if multiples biopsies are done. 8 of 9 gliomas of low histological malignancy (grade I and II) have a slow cellular kinetic. The 23 astrocytomas of different histological malignancy (grade III and IV) have variable proliferative speed (7 very fast, 8 fast and 8 slow). Only the large cells of the pinealoma are very proliferative, the lymphoid stroma is quiescent. The 5 metastasis have a slow to very fast kinetic without correlation with the cellular differentiation except in one case (important differentiation and slow cellular proliferation). The 5 lymphoma cells kinetics are well correlated with the histologic differentiation (3 large cells poor differentiated lymphomas and very fast kinetic, 2 better differentiated and slower proliferation). The 2 meningiomas proliferate slowly. The biochemical and histopathological grounds of the presented method and the limits of quantification are discussed. This method is compared with this using Bromodeoxyuridine. The correlation between proliferation and histologic malignancy is analysed. The use of cytokinetic results for therapeutic and prognosis need further statistical anatomoclinical studies. 相似文献
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The complete sequence of the S segment of Germiston bunyavirus has been determined from plasmids containing S cDNA inserts. The S segment is 980 nucleotides long with the first 15 bases at the 3' end complementary to the first 15 bases at the 5' end. Three overlapping open reading frames (ORF) were identified in the viral complementary RNA strand. The first ORF codes for a polypeptide of 233 amino acids (Mr 26,600) which is the nucleoprotein N. The second ORF codes for a polypeptide of 109 amino acids (Mr 11,800) which corresponds to the NSS protein, also called p12. Following this ORF, in the same frame, a third ORF which could encode a polypeptide of 75 amino acids was identified. Such a polypeptide has not yet been detected in infected cells. The N and NSS proteins of Germiston virus were compared with the corresponding proteins of La Crosse, snowshoe hare, and Aino viruses, and show a high extent of homology. 相似文献
7.
G R Girard W E Bondinell L M Hillegass K G Holden R G Pendleton I Uzinskas 《Journal of medicinal chemistry》1989,32(7):1566-1571
A series of 7,8-fused heterocyclic tetrahydroisoquinolines were synthesized and tested as inhibitors of rabbit adrenal phenylethanolamine-N-methyltransferase (PNMT). 6,7,8,9-Tetrahydro[1,2,3]thiadiazolo[5,4-h]isoquinoline 5 (SK&F 86607) was found to be a potent inhibitor of PNMT with an IC50 similar to that of 7,8-dichloro-1,2,3,4-tetrahydroisoquinoline (1, SK&F 64139). The isomeric tetrahydro[1,2,3]thiadiazolo[4,5-h]- and tetrahydro[1,2,5]thiadiazolo[3,4-h]isoquinolines, 13 and 20, were also potent PNMT inhibitors. However, substitution of Cl at position 5 (17) resulted in loss of potency similar to the loss observed in the 5-chloro analogue of 1. The 1,2,5 isomer 20 showed only a small drop in activity at 10(-6) M. All of the thiadiazoles were more potent than the 7,8-benzo-fused analogue 36. Fusion of other five-membered heterocyclic ring systems at the 7,8-position, e.g. triazole 22 and imidazoles 24 and 26, resulted in a decrease of PNMT inhibition. The alpha-adrenoreceptor affinities of 1 and 5 were also compared. 相似文献
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M J Girard S Saini P R Mueller T J Flotte M Staritz Y Domankevitz J T Ferrucci N Nishioka 《AJR. American journal of roentgenology》1992,159(5):991-995
OBJECTIVE. The purpose of this study was to investigate the feasibility of using a holmium:yttrium-aluminum-garnet laser to permanently occlude the cystic duct in order to isolate the gallbladder from the biliary-enteric circulation and prevent gallstone formation. MATERIALS AND METHODS. To determine the optimal laser parameters (power and pulsing rate) for cystic duct thermocoagulation, 20 freshly excised porcine gallbladders with intact cystic ducts underwent low-energy (0.075-0.085 J/pulse) or high-energy (0.20-0.25 J/pulse) thermocoagulation. Histopathologic examination was done to determine the extent of cystic duct injury. After in vitro experiments, percutaneous transcholecystic laser thermocoagulation of the cystic duct was performed on 23 anesthetized domestic pigs (four controls). Cholangiograms immediately after laser thermocoagulation were obtained to assess cystic duct occlusion. Animals were sacrificed for histopathologic correlation immediately after laser thermocoagulation (n = 4), 72 hr later (n = 4), and 6 weeks later (n = 15). RESULTS. In the in vitro studies, all 10 cystic ducts in the high-energy group were occluded, while only four in the low-energy group were occluded. At histology, all cases in both groups showed circumferential injury to the cystic duct wall without injury to the cystic artery or vein. In the in vitro experiments, the cystic duct was successfully cannulated in 21 (91%) of 23 animals. Cholangiography after thermocoagulation showed occlusion of the cystic duct in 16 (84%) of 19 cases. Immediately after laser thermocoagulation, the cystic duct mucosa was circumferentially destroyed, whereas after 72 hr necrosis of the cystic duct wall and periductal tissues had occurred. By 6 weeks, all pigs had complete cystic duct fibrosis without injury to the common bile duct. CONCLUSION. Holmium:yttrium-aluminum-garnet laser thermocoagulation of the cystic duct can be performed easily, results in immediate cystic duct occlusion, and leads to permanent fibrous ductal obliteration by 6 weeks. 相似文献
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