Effects of ascorbic acid on interactions between ciprofloxacin and ferrous sulphate, sodium ferrous citrate or ferric pyrophosphate, in mice

Rigid Oxazole Acinetobactin Analog Blocks Siderophore Cycling in Acinetobacter baumannii

The emergence of multidrug resistant (MDR) Gram-negative bacterial pathogens has raised global concern. Nontraditional therapeutic strategies, including antivirulence approaches, are gaining traction as a means of applying less selective pressure for resistance in vivo. Here, we show that rigidifying the structure of the siderophore preacinetobactin from MDR Acinetobacter baumannii via oxidation of the phenolate-oxazoline moiety to a phenolate-oxazole results in a potent inhibitor of siderophore transport and imparts a bacteriostatic effect at low micromolar concentrations under infection-like conditions.

Opposing neural effects of naltrexone on food reward and aversion: implications for the treatment of obesity

RATIONALE

Opioid antagonism reduces the consumption of palatable foods in humans but the neural substrates implicated in these effects are less well understood.

OBJECTIVES

The aim of the present study was to examine the effects of the opioid antagonist, naltrexone, on neural response to rewarding and aversive sight and taste stimuli.

METHODS

We used functional magnetic resonance imaging (fMRI) to examine the neural responses to the sight and taste of pleasant (chocolate) and aversive (mouldy strawberry) stimuli in 20 healthy volunteers who received a single oral dose of naltrexone (50 mg) and placebo in a double-blind, repeated-measures cross-over, design.

RESULTS

Relative to placebo, naltrexone decreased reward activation to chocolate in the dorsal anterior cingulate cortex and caudate, and increased aversive-related activation to unpleasant strawberry in the amygdala and anterior insula.

CONCLUSIONS

These findings suggest that modulation of key brain areas involved in reward processing, cognitive control and habit formation such as the dorsal anterior cingulate cortex (dACC) and caudate might underlie reduction in food intake with opioid antagonism. Furthermore we show for the first time that naltrexone can increase activations related to aversive food stimuli. These results support further investigation of opioid treatments in obesity.

The science and practice of micronutrient supplementations in nutritional anemia: an evidence-based review

Nutritional anemia is the most common type of anemia, affecting millions of people in all age groups worldwide. While inadequate access to food and nutrients can lead to anemia, patients with certain health status or medical conditions are also at increased risk of developing nutritional anemia. Iron, cobalamin, and folate are the most recognized micronutrients that are vital for the generation of erythrocytes. Iron deficiency is associated with insufficient production of hemoglobin. Deficiency of cobalamin or folate leads to impaired synthesis of deoxyribonucleic acid, proteins, and cell division. Recent research has demonstrated that the status of copper and zinc in the body can significantly affect iron absorption and utilization. With an increasing number of patients undergoing bariatric surgical procedures, more cases of anemia associated with copper and zinc deficiencies have also emerged. The intestinal absorption of these 5 critical micronutrients are highly regulated and mediated by specific apical transport mechanisms in the enterocytes. Health conditions that persistently alter the histology of the upper intestinal architecture, expression, or function of these substrate-specific transporters, or the normal digestion and flow of these key micronutrients, can lead to nutritional anemia. The focus of this article is to review the science of intestinal micronutrient absorption, discuss the clinical assessment of micronutrient deficiencies in relation to anemia, and suggest an effective treatment plan and monitoring strategies using an evidence-based approach.

Interaction of drug based copper(II) complexes with Herring Sperm DNA and their biological activities

Square pyramidal Cu(II) complexes with NS donor ligand and ciprofloxacin have been synthesized and characterized using analytical and spectral techniques. The synthesized complexes have been tested for their antimicrobial activity using double dilution technique in terms of minimum inhibitory concentration (MIC) and colony forming unit (CFU). The DNA binding ability of the complexes with Sperm Herring DNA has been performed using absorption titration and viscosity measurement. The nuclease activity of complexes with plasmid DNA (pUC19) has been carried out using agarose gel electrophoresis technique. Synthesized complexes have been tested for their SOD mimic activity using NBT/NADH/PMS system. The cytotoxic properties of metal complexes have been evaluated using brine shrimp lethality bioassay.

In vitro food-drug interaction study: Which milk component has a decreasing effect on the bioavailability of ciprofloxacin?

The purpose of the present work was developing an in vitro dissolution test to highlight the possible molecular background causing ciprofloxacin (CPFX)-milk interaction. The in vitro dissolution of CPFX from film-coated tablets (Ciprinol) 500mg) was examined at different pH values, simulating certain parts of the gastrointestinal tract, in the presence of water, low-fat milk, casein- or calcium enriched water. In order to determine the amount of dissolved CPFX, solid phase extraction sample preparation followed by high performance liquid chromatography coupled with mass spectrometry was applied. Comparing the dissolution efficiency values in various media, it can be concluded, that casein has a more pronounced effect on the absorbable amount of the antibiotic at each pH value studied, than calcium. In the case of concomitant intake of CPFX film-coated tablet and milk or other dairy products not only the complexation with calcium, but also the adsorption of CPFX on the surface of proteins decreases the absorbable amount of CPFX.

Synthesis, characterization, antibacterial and anti-inflammatory activities of enoxacin metal complexes

The present work comprises the synthesis of enoxacin (Heno) complexes with various transition metals. Two types of complexes [M(eno)₂(H₂O)₂]3H₂O(M = Cu^II, Ni^II or Mn^II) and [M(eno)(H₂O)₂]Cl · 4H₂O (M = Fe^III) were obtained. The complexes were characterized by different physicochemical, spectroscopic, and elemental analysis. Results suggest that enoxacin interacts with the metals as a monoanionic bidentate ligand. These complexes were also tested for their antibacterial activity against eleven (11) different microorganisms, and the results were compared with the parent drug. Moreover all the metal complexes were also tested for their ability to scavenge reactive oxygen species where by Mn^II and Cu^II complexes exhibited potential to mediate anti-inflammatory response.

Beta-phenylethylamines and the isoquinoline alkaloids

This review covers beta-phenylethylamines and isoquinoline alkaloids and compounds derived from them, including further products of oxidation, condensation with formaldehyde and rearrangement, some of which do not contain an isoquinoline system, together with naphthylisoquinoline alkaloids, which have a different biogenetic origin. The occurrence of the alkaloids, with the structures of new bases, together with their reactions, syntheses and biological activities are reported. The literature from July 2001 to June 2002 is reviewed, with 581 references cited.

Impairment of mycophenolate mofetil absorption by calcium polycarbophil

The effect of calcium polycarbophil on the absorption of mycophenolate mofetil, an immunosuppressive agent, was evaluated in healthy subjects. In vitro studies were performed to further evaluate the mechanism of the potential interaction. In the in vitro study, the release of mycophenolate mofetil from a cellulose membrane in the presence or absence of metal cations was measured using the dissolution test procedure. In the in vivo study, a randomized crossover design with two phases was used. In one phase, 6 male healthy volunteers received 1000 mg of mycophenolate mofetil alone (treatment 1); in the other phase, they received 1000 mg of mycophenolate mofetil and 2400 mg of calcium polycarbophil fine granules concomitantly (treatment 2). They received 30 mg of lansoprazole for 5 days and, on the 6th day, received mycophenolate mofetil and 2400 mg of calcium polycarbophil fine granules concomitantly (treatment 3). The serum concentration of mycophenolic acid was measured by high-performance liquid chromatography. In the in vitro study, the release from a cellulose membrane in the presence of calcium or iron ions was slower than that in the absence of these metal ions. In the in vivo study, the AUC0-12 and C(max) in treatment 2 were less than those in treatment 1. About 50% and 25% decreases in AUC0-12 in treatment 2 and treatment 3 were observed compared with those in treatment 1, respectively. These findings suggest that when mycophenolate mofetil and calcium polycarbophil were coadministered concomitantly, a decrease in mycophenolate mofetil absorption was observed. Therefore, it appears clear that the concomitant administration of mycophenolate mofetil and calcium polycarbophil should be avoided.

Impairment of ciprofloxacin absorption by calcium polycarbophil

The effect of calcium polycarbophil on the absorption of ciprofloxacin, a broad-spectrum antibacterial agent, was evaluated in an in vitro and in vivo study. In the in vitro study, the release of ciprofloxacin from the cellulose membrane in the presence or absence of metal cations was measured using the dissolution test procedure. In the in vivo study, male ST Wistar rats and male volunteers were employed. First, 20 mg/kg of ciprofloxacin alone (Rat Study 1) or 20 mg/kg of ciprofloxacin in combination with 64 mg/kg of calcium chloride (Rat Study 2) was administered orally to 3 rats. Second, a volunteer study was employed and a randomized crossover design with twophases was used. In onephase, volunteers received 400 mg of ciprofloxacin alone (Study 1); in the other phase, they received 400 mg of ciprofloxacin and 1200 mg of fine calcium polycarbophil granules concomitantly (Study 2). The plasma and serum concentrations of ciprofloxacin were measured by high-performance liquid chromatography. The release of ciprofloxacin from the cellulose membrane in the presence of aluminum, calcium, or iron ions was slower than that in the absence of these metal ions. The AUC0-4 and Cmax in Rat Study 2 were lower than those respective values in Rat Study 1. AUC0-4 was approximately 60% lower in Rat Study 2 than Rat Study 1. In the volunteer study, the AUC0-12 and Cmax in Study 2 were lower than those respective values in Study 1. In particular, AUC0-12 was approximately 50% lowerin Study 2 than in Study 1. These findings suggest that when ciprofloxacin and calcium polycarbophil were coadministered concomitantly, a decrease of ciprofloxacin absorption was observed, and this action was caused by the formation of chelate complexes. Therefore, it seems clear that we should avoid the concomitant administration of ciprofloxacin and calcium polycarbophil.