Cucurbitacins as Constituents of Wilbrandia ebracteata

The methanolic extract from the roots of WILBRANDIA EBRACTEATA afforded, in addition to the known dihydrocucurbitacins B and E, dihydroisocucurbitacin B, Cucurbitacins B, D, E, G, H, P, and 22-deoxycucurbi-tacin D, four new compounds whose structures were elucidated as (20 R,24xi)-3)3beta,16alpha,20)24,25-pentahydroxy-10alpha-cucurbit-5-ene-2,11,22-trione (3- EPI-isocucurbitacin G) ( 8), (20 R,22xi)-2beta16a,20,22,25-pentahydroxy-10alpha-cucurbita-5,23 T-diene-3,11-dione ( 13), (20 R)-25-acetoxy-3,16alpha,20-trihydroxy-30- NOR-2-(beta- D-glucopyranosyloxy)-1,2,3,4,5,10-dehydrocucurbit-6-ene-11,22-dione ( 14), and dihydroisocucurbitacin B-3-glucoside ( 16).     

Retrospective analysis of 31 cases of nasopalatine duct cyst

OBJECTIVE: To perform a retrospective analysis of patients with nasopalatine duct cysts (NPDC) in Brazil and compare with previous analyses. MATERIALS AND METHODS: The files of the Laboratory of Oral Pathology (Minas Gerais Federal University) from 1966 to 1997 were reviewed. Demographic, clinical and histologic data of patients with nasopalatine duct cysts were collected. RESULTS: The mean age of patients with nasopalatine duct cysts at the time of diagnosis was 37.4 years and with a predilection for males. The majority of cases were asymptomatic. Histologically, non-keratinized stratified squamous epithelium alone or in combination with other epithelia was observed in 93% of the cases. Recurrence was not recorded. CONCLUSION: The demographic, histopathological, radiographic, and clinical data of the NPDC in our series are similar to previous studies in other populations.     

Identification of a new Lesch-Nyhan syndrome mutation (HPRTBrasil) and analysis of potentially heterozygous females

The mutation in the hypoxanthine-guanine phosphoribosyltransferase (HPRT) gene has been determined in two brothers affected with Lesch-Nyhan syndrome. Female members of the family who are at risk for being heterozygous carriers of the HPRT mutation were also studied to determine whether they carry the mutation. DNA sequencing revealed that the boys' mother is heterozygous for the mutation in her somatic cells, but that three maternal aunts are not heterozygous. Such carrier information is important for the future pregnancy plans of at-risk females. The mutation, an A-->T transversion at cDNA base 590 (590A-->T), results in an amino acid change of glutamic acid to valine at codon 197, and has not been reported previously in a Lesch-Nyhan syndrome male. This mutation is designated HPRTBrasil.     

Inhibition of fibrinolysis by a synthetic urokinase inhibitor enhances lung colonization of metastatic murine mammary tumor cells

We have investigated the role of coagulation and fibrinolysis during the metastatic lung colonization of F3II mouse mammary carcinoma cells. The selective synthetic urokinase inhibitor B623 significantly enhanced lung colonization and blocked the antimetastatic effect of heparin when administered i.p. during the first stages of metastasis formation. In B623-treated mice the overall activity of the fibrinolytic system was reduced and circulating urokinase was specifically inhibited by this agent. In vitro studies demonstrated that B623 induces the aggregation of F3II cells in the presence of mouse plasma and facilitates the entrapment of tumor cells in a fibrin gel matrix. Our data suggest that imbalances of fibrin deposition and removal may dramatically influence metastatic lung colonization.     

Headache and oral contraceptives (author's transl)

175 patients using oral contraceptives (OCs) for periods from 2 months-6 years were studied. A survey was made of the secondary effects of the treatment. Among the total group, 101 of them had not presented headache before the use of contraceptives, and the remaining 75 patients had previously complained of chronic headaches which were considered due to different etiologies. 50 patients from the group without previous headache claimed that OC treatment marked the initiation of the headaches. 25 had vascular headaches and 25 had tension headaches. Among the 75 patients included in the other group as complainers of chronic headache prior to treatment, 30 had a worsening of the symptoms after use of the OCs. The authors compare their results with those referred to in the literature. (author's)     

Veratridine modifies the TTX-resistant Na channels in rat vagal afferent neurons

A number of neurotoxins from venoms of invertebrates and plants are ligands for voltage-gated Na⁺ channels and are useful tools for studying Na⁺ channel function and structure. Using whole-cell recordings from vagal afferent nodose neurons, we studied neurotoxins that target Na⁺ channels. We asked whether Ts3 (an α-scorpion toxin) and/or veratridine (a lipid-soluble toxin), could modify the TTX-resistant Na⁺ current generated by vagal afferent nodose neurons. Nodose TTX-resistant current was not affected by Ts3, whereas Ts3 slowed inactivation of the current generated by TTX-sensitive current component. We found that veratridine inhibited the TTX-resistant Na⁺ currents on rat nodose neurons. Interestingly, veratridine-modified Na⁺ channels developed a persistent current that accounted for the large tail current observed. We propose that veratridine modifies TTX-resistant Na⁺ channels through a mechanism distinct from its actions on other voltage-gated Na⁺ channels.     

Detection of microcystin synthetase genes in health food supplements containing the freshwater cyanobacterium Aphanizomenon flos-aquae.

In this study we investigated the presence of toxin-producing cyanobacterial contaminants in food supplements manufactured from blooms of the non-toxic freshwater cyanobacterium Aphanizomenon flos-aquae. Previous reports investigating the contamination of health food supplements with toxin-producing cyanobacteria have used chemical and or biochemical methods such as HPLC, ELISA and protein phosphatase assays. Whilst these studies have drawn attention to the presence of hepatotoxic microcystins in some commercially available food supplements, the methods used do not provide any information on the source of the contaminant. Such information would be useful for the quality control of food supplements produced for human consumption. In this study we applied a molecular technique, involving the amplification of the 16s rRNA gene, the phycocyanin operon, and two genes of the microcystin synthetase gene cluster to show that all 12 food supplement samples, sourced from various internet distributors and containing non-toxic A. flos-aquae, also contained toxigenic cyanobacteria. Sequencing of the microcystin synthetase genes detected in all of the food supplements showed that M. aeruginosa was the organism responsible for the production of microcystins in the samples. The presence of microcystins in the food supplements was confirmed by ELISA, with concentrations within the range of 0.1--4.72 microgg(-1) (microcystin-LR equivalents). Given that the molecular methods applied here are highly sensitive, and show good agreement with the results obtained from ELISA, we believe that they could potentially be used as a quality control technique for food products that contain cyanobacteria.     

Anti-inflammatory effects of fructose-1,6-bisphosphate on carrageenan-induced pleurisy in rat.

In the present study, we evaluated the effect of fructose-1,6-bisphosphate (FBP), a high energy intermediate metabolite of glycolysis, in an acute model of lung injury. Injection of carrageenan into the pleural cavity of rats elicited an acute inflammation response characterized by a fluid accumulation in the pleural cavity which contained a large number of polymorphonuclear neutrophils. FBP (500mg/kg) attenuated the inflammation parameters: exudate volume, total leukocytes and the number of polymorphonuclear leukocytes, but the protein concentration in the exudate was not significantly affected by treatment with FBP. The precise site and mechanism of the anti-inflammatory effect was not addressed, considering the diverse pharmacological actions of FBP. This drug has anti-inflammatory actions suggesting that it may represent a novel strategy for the modulation of inflammatory response.