64 research outputs found

    Disruption of the blood-brain barrier by intra-arterial administration of papaverine: a technical note

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    INTRODUCTION: Various endovascular techniques can be used to treat cerebral vasospasm after aneurysmal subarachnoid haemorrhage (SAH) including intra-arterial administration of vasodilator drugs such as papaverine or nicardipine and balloon dilatation of the affected vessel segment. Papaverine is known to have side effects, and we report a possible new one. MATERIALS AND METHODS: After the treatment of cerebral vasospasm in a SAH patient by intra-arterial administration of papaverine into the left posterior cerebral artery, severe mesencephalic extravasation of blood and contrast media was detected. RESULTS: After reviewing the literature, the authors conclude that interruption of the blood-brain barrier by papaverine most likely combined with a secondary hyperperfusion phenomena, and perhaps a direct toxic effect on brain tissue was the mechanism of this major complication. CONCLUSION: In treating vasospasm in areas with a high density of perforating arteries, especially in the posterior circulation, papaverine should be used cautiously because a safe regimen has yet to be established. In this situation, alternative agents such as calcium channel blockers could be considered, but evidence-based data are still missing

    Cobalt-katalysierte enantioselektive Hydrierung von dreifach substituierten carbocyclischen Olefinen:Zugang zu chiralen cyclischen Amiden

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    Die enantioselektive Hydrierung von cyclischen Enamiden wurde mit einem Cobalt-Bisphosphin-Katalysator erreicht. Die Reduktion verschiedenster dreifach substituierter carbocyclischen Enamide zu den entsprechenden gesättigten Amiden erfolgte mit hoher Aktivität und ausgezeichneter Enantioselektivität (bis zu 99 %) unter Verwendung des Systems CoCl2/(S,S)-Ph-BPE. Die Methode lässt sich auf die Synthese chiraler Amine durch eine basische Hydrolyse der Hydrierungsprodukte ausweiten. Erste mechanistische Untersuchungen deuten auf die Anwesenheit einer high-spin Cobalt(II)-Spezie im katalytischen Cyclus hin. Wir postulieren die Hydrierung der Kohlenstoff-Kohlenstoff-Doppelbindung über einen Sigma-Bindungs-Metathese-Weg

    Mitochondrial Side Effects of Surgical Prophylactic Antibiotics Ceftriaxone and Rifaximin Lead to Bowel Mucosal Damage

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    Despite their clinical effectiveness, a growing body of evidence has shown that many classes of antibiotics lead to mitochondrial dysfunction. Ceftriaxone and Rifaximin are first choice perioperative antibiotics in gastrointestinal surgery targeting fundamental processes of intestinal bacteria; however, may also have negative consequences for the host cells. In this study, we investigated their direct effect on mitochondrial functions in vitro, together with their impact on ileum, colon and liver tissue. Additionally, their impact on the gastrointestinal microbiome was studied in vivo, in a rat model. Rifaximin significantly impaired the oxidative phosphorylation capacity (OxPhos) and leak respiration in the ileal mucosa, in line with increased oxidative tissue damage and histological changes following treatment. Ceftriaxone prophylaxis led to similar changes in the colon mucosa. The composition and diversity of bacterial communities differed extensively in response to antibiotic pre-treatment. However, the relative abundances of the toxin producing species were not increased. We have confirmed the harmful effects of prophylactic doses of Rifaximin and Ceftriaxone on the intestinal mucosa and that these effects were related to the mitochondrial dysfunction. These experiments raise awareness of mitochondrial side effects of these antibiotics that may be of clinical importance when evaluating their adverse effects on bowel mucosa

    Deviations in Circulating TNF α

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    Objectives. Tumor necrosis factor alpha (TNFα) plays a pivotal role in the inflammatory host response. The serum-level of TNFα and the production of TNFα by lympho/monocytes, however, seem to show high individual variations. The goal of the present study was to investigate the variations and inducibility of TNFα-activity in two age-groups of healthy volunteers. Methods. Sixty elderly, healthy volunteers were studied. These persons were free of malignant diseases, and within three months, they did not have any trauma or inflammatory disease and were not taking any steroids or nonsteroid anti-inflammatory drugs. Thirty young volunteers were also included. Blood samples were taken; lympho/monocytes were separated and cultured with or without endotoxin (LPS) stimulation. Serum and culture supernatant TNFα levels were determined by bioassay using WEHI 164 cells. Results. The results indicated significant individual variations in TNFα levels of healthy volunteers irrespective of age. Subgroups with low, middle, and high serum TNF-levels were distinguished. In about 50% of volunteers with low serum-TNFα activity, LPS stimulation failed to increase the TNFα production by isolated lympho/monocytes. Conclusion. Our data suggest a chance to select individuals with enhanced sensitivity for septic complications

    New national and regional bryophyte records, 52

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    Marchantia paleacea is a new species for the Umbria Region and is rare in central and southern Italy. This record is in a Site of Community Importance (SCI) IT5220017 and a Special Area of Conservation (SAC) of the Natura 2000 EU-wide network due to the presence of the 7220* ‘Petrifying springs with tufa formation (Cratoneurion)’ Annexe I priority habitat. The particular environment, with a gorge and waterfall, created a very special microclimate that allowed the establishment of interesting liverworts and mosses

    Synthetic Heparan Sulfate Oligosaccharides Inhibit Endothelial Cell Functions Essential for Angiogenesis

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    Heparan sulfate (HS) is an important regulator of the assembly and activity of various angiogenic signalling complexes. However, the significance of precisely defined HS structures in regulating cytokine-dependent angiogenic cellular functions and signalling through receptors regulating angiogenic responses remains unclear. Understanding such structure-activity relationships is important for the rational design of HS fragments that inhibit HS-dependent angiogenic signalling complexes.We synthesized a series of HS oligosaccharides ranging from 7 to 12 saccharide residues that contained a repeating disaccharide unit consisting of iduronate 2-O-sulfate linked to glucosamine with or without N-sulfate. The ability of oligosaccharides to compete with HS for FGF2 and VEGF165 binding significantly increased with oligosaccharide length and sulfation. Correspondingly, the inhibitory potential of oligosaccharides against FGF2- and VEGF165-induced endothelial cell responses was greater in longer oligosaccharide species that were comprised of disaccharides bearing both 2-O- and N-sulfation (2SNS). FGF2- and VEGF165-induced endothelial cell migration were inhibited by longer 2SNS oligosaccharide species with 2SNS dodecasaccharide activity being comparable to that of receptor tyrosine kinase inhibitors targeting FGFR or VEGFR-2. Moreover, the 2SNS dodecasaccharide ablated FGF2- or VEGF165-induced phosphorylation of FAK and assembly of F-actin in peripheral lamellipodia-like structures. In contrast, FGF2-induced endothelial cell proliferation was only moderately inhibited by longer 2SNS oligosaccharides. Inhibition of FGF2- and VEGF165-dependent endothelial tube formation strongly correlated with oligosaccharide length and sulfation with 10-mer and 12-mer 2SNS oligosaccharides being the most potent species. FGF2- and VEGF165-induced activation of MAPK pathway was inhibited by biologically active oligosaccharides correlating with the specific phosphorylation events in FRS2 and VEGFR-2, respectively.These results demonstrate structure-function relationships for synthetic HS saccharides that suppress endothelial cell migration, tube formation and signalling induced by key angiogenic cytokines

    Cuscuta subgenus Grammica (Convolvulaceae) on the Palni Hills with a new record

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    Cuscuta campestris Yuncker is recorded as a novum on the Palni Hills (India). The parasite occurs in great quantities along the edge of roads, agricultural fields (mostly coffee plantations) and along the bank of streams. The species parasitized every herbaceous plant which came into contact with it. In the examined herbaria every specimen that was collected from the hills under the name of C. chinensis Lam. was reidentified as C. campestris . In addition, despite of the systematic field research there was not found any C. chinensis specimen on the Palni Hills. In this study, several illustrations of C. chinensis are collected and displayed, furthermore the international literature of the morphology and taxonomy of the species are reviewed
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