Tamoxifen derivatives for delivery of the antitumoral (DACH)Pt group: selective synthesis by McMurry coupling,and biochemical behaviour

The goal of our study was to potentiate the effects of the ((R,R)-trans-1,2-diaminocyclohexane)-platinum(II) fragment [(DACH)Pt], known for its cytotoxic properties, either with tamoxifen (Tam), the most widely used antiestrogen in the treatment of hormone-dependent breast cancers, or with its active metabolite hydroxytamoxifen (hydroxy-Tam). We coupled Tam or hydroxy-Tam derivatives bearing a malonato group at the para position of the beta aromatic ring with the (DACH)Pt fragment. The malonato-Tam and malonato-hydroxy-Tam compounds were prepared through McMurry coupling of the appropriate ketones. The presence of the malonate group resulted in a pronounced stereospecificity in the reaction, since malonato-Tam was obtained only as the Z isomer, while malonato-hydroxy-Tam was obtained as an 80/20 E/Z mixture. Attribution of the isomeric structures was achieved by 2D NMR spectroscopy. The platinum complexes (DACH)Pt-malonato-Tam and (DACH)Pt-malonato-hydroxy-Tam were then prepared by coupling the barium salts derived from the malonato-Tam and malonato-hydroxy-Tam with the nitrate derived from (DACH)PtCl(2). Study of the biochemical properties of these two platinum complexes showed that, while the hydroxy-Tam complex is satisfactorily recognized by the estrogen receptor (relative binding affinity, RBA=6.4 %), the Tam complex is less well recognized (RBA=0.5 %). The effects of these complexes on two hormone-dependent breast cancer cell lines (MCF7 and MVLN) were studied in vitro. Both complexes showed an antiproliferative effect on MCF7 cells, and an antiestrogenic effect on MVLN cells. The observed effects appear to be essentially antihormonal, since incorporation of the (DACH)Pt fragment into the tamoxifen skeleton did not cause an increase in the cytotoxicity of the complexes.     

Efficacy of different chemicals on shelf life extension of parsley stored at two temperatures

Four different chemical treatments, GA₃, 1‐MCP, essential oils and nano‐Cu, were applied immediately after harvest to Petroselinum crispum (Mill) plants. The efficacy of the above chemicals on shelf life extension of parsley stored at 5 °C and 20 °C was determined by analysing physiological and biochemical factors that determine quality standards of storage fresh parsley. Nonsprayed parsley revealed the highest loss of weight, ascorbic acid, pigments and an enhancement of CO₂ production and lipid peroxidation at 5 °C and 20 °C of storage. Nano‐Cu was more effective for delaying weight loss and revealed a better storage capacity. GA₃, 1‐MCP and essential oils sprays were more effective in ascorbic acid retention at 20 °C than at 5 °C, whereas all substances protect samples from lipid peroxidation. Essential oils were more clearly inhibitory towards both total viable counts and yeast infection. Our results suggest that GA₃, 1‐MCP, essential oils and Nano‐Cu exert their function through different mechanisms during ripening and could provide an effective and complementary means for maintaining high‐quality parsley leaves after harvest.     

Expression and stabilization of galactose oxidase in Escherichia coli by directed evolution

We have used directed evolution methods to express a fungalenzyme, galactose oxidase (GOase), in functional form in Escherichiacoli. The evolved enzymes retain the activity and substratespecificity of the native fungal oxidase, but are more thermostable,are expressed at a much higher level (up to 10.8 mg/l of purifiedGOase), and have reduced negative charge compared to wild type,all properties which are expected to facilitate applicationsand further evolution of the enzyme. Spectroscopic characterizationof the recombinant enzymes reveals a tyrosyl radical of comparablestability to the native GOase from Fusarium.     

Sensory characteristics and iron dialyzability of gluten-free bread fortified with iron

The objectives of the present study were (a) to produce gluten-free bread, fortified with iron (GFB-Fe), using selected iron compounds (ferric pyrophosphate, ferric pyrophosphate with emulsifiers, NaFeEDTA, electrolytic iron, ferrous gluconate, ferrous lactate and ferrous sulphate) (b) to test sensory characteristics of the GFB-Fe (feel-mouth texture, crumb colour, aroma and taste) (c) to compare iron dialyzability of various iron compounds in GFB-Fe. The most acceptable products were those fortified with ferric pyrophosphate with emulsifiers and ferric pyrophosphate. Ferrous dialyzable iron (ferrous iron with molecular weight lower than 8000 Da, an index for prediction of iron bioavailability) was measured under simulated gastrointestinal conditions. Ferrous dialyzable iron in GFB-Fe fortified with ferric pyrophosphate with emulsifiers, NaFeEDTA, ferrous bis-glycinate, ferrous gluconate or ferrous sulphate was higher than that in GFB-Fe fortified with electrolytic iron, ferrous lactate or ferric pyrophosphate (P < 0.05). These results are promising for the development of GFB-Fe products in the future.     

Nanometric Micelles with Photo‐Triggered Cytotoxicity

The development of a photo‐responsive micellar system capable of triggering cell death is reported. Precursors of the micelles are synthesized by connecting a lipophilic chain to a hydrophilic polyethylene glycol via a photo‐labile nitrobenzyl group. The resulting amphiphilic units are self‐assembled in water forming 12 nm micelles that are readily internalized into cells. Upon photo‐irradiation, micelles undergo cleavage and yield a cytotoxic nitrosobenzaldehyde derivative, which significantly inhibits the proliferation of MDA‐MB‐231 cells under standard in vitro conditions.     

An overview of rheumatological research in the European Union

We describe a case of a 73-year-old male with a rare T-cell lymphoma that presented deceptively as progressive hepatic failure with fever, weight loss, pancytopenia, mental confusion, splenomegaly, and no lymphadenopathy. An alcoholic history supported the diagnosis of cirrhosis, but a liver biopsy was not performed. A bone marrow biopsy was considered unremarkable. Death occurred after a course of four months. Postmortem examination showed hepatic, splenic, lymph node, and marrow infiltration by characteristically sparse, isolated, bizarre, medium-to-large sized neoplastic cells with extensive hepatic centrilobular necrosis, steatosis, and predominant splenic involvement. Immunohistochemical markers indicated a T-cell lymphoma consistent with either an alpha/beta peripheral T-cell lymphoma or a gamma/delta lymphoma. Definitive immunotyping was not available. However, the pathologic features are most consistent with a gamma/delta T-cell lymphoma. This case is an example of a rare, rapidly progressive lymphoma, which is a recognized clinical entity, easily missed, and treatable. Its diagnostic consideration must be explicitly communicated to pathologists, because the isolated or sparse tumor cells in a lymph node, liver, or bone marrow biopsy may easily be mistaken for variants of megakaryocytes or histiocytes.     

Comparison of 24-h control of gastric acidity by three different dosages of pantoprazole in patients with duodenal ulcer

BACKGROUND: It is now clear that the extent to which gastric acid secretion must be suppressed varies with the clinical condition being treated. AIM: To assess the 24-h control of gastric acidity and the individual response variability of three different doses of pantoprazole. METHODS: Sixty-four duodenal ulcer patients were recruited for this prospective, randomized, multicentre, double-blind, parallel-group study. They were subdivided into three well-matched groups treated with 20 mg o.m., 40 mg o.m. and 40 mg b.d. of pantoprazole, respectively. Endoscopy and intragastric pH monitoring were performed in each patient before and after 14 days of treatment. RESULTS: Fifty-five patients were eligible for final analysis (17 treated with 20 mg o.m., 18 with 40 mg o.m. and 20 with 40 mg b.d. pantoprazole). The ulcer crater healed in 94, 88 and 95% of cases, respectively. The three dosages of pantoprazole produced significant increases in gastric pH compared to basal levels (P < 0.0001). There was also a clear dose-dependent pharmacodynamic effect, which augmented on moving from the lowest dosage of 20 mg o.m. pantoprazole to the highest dosage of 40 mg b.d. (P < 0.01-0.001). The inter-individual response variability within the three treatment groups was more marked with the dose of 20 mg than with the two higher doses of pantoprazole. CONCLUSIONS: All three doses of pantoprazole we tested are highly effective in decreasing gastric acidity and there is a clear dose-dependent pharmacodynamic effect on moving from the lowest to the highest dosage. The greatest inter individual variation in the degree of acid inhibition was seen with pantoprazole 20 mg o.m., while the majority of patients responded adequately to the two higher doses of the drug.     

The Role of Leptin in Childhood Immune Thrombocytopenia (ITP): An Anti-Inflammatory Agent?

To investigate the effect of leptin in childhood ITP, we measured plasma leptin in 39 children with acute ITP, after treatment and in remission, and in 33 healthy age/BMI-matched controls. We also cultured ITP and control peripheral blood mononuclear cells (PBMCs) with recombinant leptin to assess its direct effect on pro/anti-inflammatory cytokine gene expression. A significant increase in leptin was observed in children with active disease compared to controls. A significant inverse correlation of leptin with platelet count was also observed in children with acute ITP. Leptin remained high after treatment with IVIg, whereas steroid treatment lowered leptin below control levels. In remission, leptin was in the control range. Cytokine gene expression was significantly increased in children with acute ITP compared with controls, with highest expression for IFN-γ and IL-10. IVIg/steroid treatment significantly decreased IFN-γ and IL-10 expression. In remission, IFN-γ and IL-10 expression remained low. Addition of leptin to PBMCs isolated from patients in remission resulted in a significant increase in IL-10 gene expression compared to controls. Further experiments with purified T-cells and monocytes identified monocytes as the source of leptin-induced IL-10. We suggest that leptin acts as an active anti-inflammatory agent in childhood ITP by promoting IL-10 secretion by monocytes.     

Survival of Listeria monocytogenes in a simulated dynamic gastrointestinal model during storage of inoculated bologna and salami slices in vacuum packages

Listeria monocytogenes counts were determined during storage (82 days, 4 degrees C) in vacuum packages of inoculated bologna and salami slices and after exposure to a simulated dynamic model of the stomach and small intestine. Variables controlled in the model included gastric emptying and gastrointestinal fluid secretion rates, gradual gastric acidification, and intestinal pH maintenance. L. monocytogenes populations increased on bologna and decreased on salami, reaching 8.7 and 1.4 log CFU/g, respectively, on day 82. Inactivation rates (IR) during gastric exposure of bologna and salami ranged from 0.079 (day 14) to 0.158 (day 57) log CFU/g/min and from 0.013 (day 42) to 0.051 (day 1) log CFU/g/min, respectively. On corresponding days, gastric IR for cells on salami were lower than on bologna, suggesting potential protective effects of the former product. However, it is also possible that the low initial L. monocytogenes levels reached with storage of salami (< or = 2.5 log CFU/g after day 27) may have resulted in slower reductions than in the high levels on bologna. Gradual decline of gastric pH allowed survival in the gastric compartment during the initial stages, which resulted in a large fraction of the cells being delivered into the intestinal compartment. Intestinal IR ranged from 0.003 to 0.048 (bologna) and from 0.002 to 0.056 (salami) log CFU/g/min throughout storage. Although findings indicated potential effects of salami against gastric killing of L. monocytogenes, any effects of the food matrix per se on the gastrointestinal survival of the pathogen were overwhelmed by the high and low contamination levels reached on bologna and salami, respectively, during storage.