133Granulation Tissue Induction by Lassar Ointment vs. Collagen‐Polyvynilpyrrolidone in Venous Ulcers

Venous leg ulcers derived from tissue destruction is the consequence of a chronic inflammatory process that produces pain and physical disability, diminishing quality of life in patients. In this work, Lassar ointment and lyophilized collagen‐polyvinylpyrrolidone were administered separated each on one half in the same ulcer to 9 patients at the beginning and every 4 days. On day 16, all patients were auto‐grafted with partial thickness skin. Granulation tissue and graft integration were assessed clinically during 3 months. Inflammatory infiltrate, type I and III collagens, elastic fibers, alkaline phosphatase as well as blood vessels were evaluated histologically or histochemically in biopsies taken at the beginning and 16 days after the local treatment. Clinically and morphologically, both treatments demonstrated appropriate granulation tissue promotion and optimal graft integration since the beginning. Nevertheless, in Lassar ointment treated group regionalization of alkaline phosphatase activity was observed, as well as the presence of granuloma in 2 of the 9 patients. In conclusion, Lassar ointment or lyophilized collagen‐polyvinylpyrrolidone are two different promoters of granulation tissue in venous leg ulcers, however Lassar ointment has the capability to produce granuloma and an exacerbated immune response; in consequence, ulcer recidivism could be present, may be due to mineral deposits in the wound.     

High-dose infliximab prophylaxis in endotoxin-induced uveitis.

PURPOSE: The aim of this study to analyze the preventive effect of high-dose infliximab in endotoxin-induced uveitis (EIU) in rabbits. METHODS: An experimental study was conducted on 64 rabbits. Salmonella typhimurium lipopolysaccharide endotoxin was intravitreally injected. Infliximab was intravenously (i.v.) injected 24 h before the intravitreal injection (20 mg/kg). The animals were randomly assigned to five groups: group A, saline intravitreal injection; group B, Infliximab i.v. group C, infliximab + saline; group D, intravitreal endotoxin and group E, infliximab i.v. + intravitreal endotoxin. With two masked observers, a microscopic examination of aqueous humor (cells, tumor necrosis factor [TNF] alpha) and aqueous protein level were performed 24 h after an endotoxin injection and 48 h after an infliximab infusion. RESULTS: Infliximab treatment, at a dose of 20 mg/kg, significantly improved all the parameters. Inflammatory cell infiltration was significantly reduced in the iris, ciliary body, and anterior chamber (U Mann-Whitney test, P = 0.01). Associated with a lower level of TNF-alpha and protein exudate in aqueous humor (U Mann-Whitney test, P = 0.01). CONCLUSIONS: Infliximab, at a dose of 20 mg/kg, is effective in the prophylaxis of the EIU.     

Comparison between Low Frequency Magnetic Field Stimulation and Nerve Growth Factor Treatment of Cultured Chromaffin Cells, on Neurite Growth, Noradrenaline Release, Excitable Properties, and Grafting in Nigrostriatal Lesioned Rats

Adrenal chromaffin cells in vitro respond to nerve growth factor (NGF) by expressing neuronal traits. Low frequency magnetic (LFM) field stimulation, while inducing a variety of effects on several cell types, has never been studied as to its effects on chromaffin cell cultures. The purpose of this study was to compare the effects of LFM field stimulation with that of NGF on the morphological phenotype, on noradrenaline (NA) release, and on membrane excitability of cultured chromaffin cells. We also tested the effects of grafting LFM and NGF-treated chromaffin cells into the caudate nucleus of rats with 6-hydroxydopamine lesions of the nigrostriatal pathway. The results of this study showed that LFM field stimulation produced neurite growth of cultured chromaffin cells in a manner similar to that of NGF exposure. The combination of the two procedures did not induce changes above those observed by NGF alone. Both NGF- and LFM-treated chromaffin cells released [³H]NA equally in response to a depolarizing concentration of KCl. On the other, Na⁺ current density of LFM field stimulation increased, but to a lesser extent than that seen in NGF-treated cells. In addition both types of cells when transplanted into nigrostriatal-lesioned animals induced a similar decrease in the motor asymmetries produced by the lesion. When NGF- or LFM-treated chromaffin cells where compared to untreated control cells, no significant differences were observed in [³H]NA release, on Na⁺ current densities, or on postgraft motor asymmetries. The results are discussed in terms of the fact that LFM-stimulated cells can be differentiated in a manner similar to NGF-treated cells, by acquiring sympathetic like traits which in turn can diminish motor asymmetries when grafted into nigrostriatal-lesioned rats.     

Architectural organisation of neuronal activity-associated magnetic fields: a hypothesis for memory

Despite intensive investigation into the mechanisms underlying the memory process, the physical bases for this superior cognitive function remain elusive. Neuronal activity-associated magnetic fields (NAAMFs) hypothesis of memory suggests that items of information are stored as three-dimensional bundles of magnetic fields associated to the complex but extremely organised cerebral cortex. The present paper proposes a plausible architectural organisation of neuronal activity-associated magnetic fields that may explain how information could be stored in the human cerebral cortex. Magnetic fields generated as consequence of neuronal minicolumns activation could modify the basal "electromagnetic status" of the closest astrocytes allowing codification and storage of information.     

A novel fungal prenyl diphosphate synthase in the dimorphic zygomycete Mucor circinelloides

Two Mucor circinelloides structural genes involved in isoprenoid biosynthesis were isolated and characterised. The isoA gene encodes a typical eukaryotic farnesyl diphosphate synthase (EC 2.5.1.10), whereas the isoB gene deduced amino acid sequence shows similarity to fungal medium-chain prenyl diphosphate synthases. By functional complementation in Escherichia coli, the isoB gene product was shown to be a solanesyl diphosphate synthase (EC 2.5.1.11), which is the first fungal enzyme reported having this specificity. In addition, a M. circinelloides one-marker-per-chromosome map was completed by contour-clamped homogeneous electric field localisation of isoA, isoB and three other isoprenoid biosynthesis genes to individual chromosomes.Abbreviations FPP farnesyl diphosphate (or pyrophosphate) - GGPP geranylgeranyl diphosphate - PrenylPP prenyl diphosphate - DPP decaprenyl diphosphate - HPP hexaprenyl diphosphate - SPP solanesyl diphosphate