A water-soluble alternative to simethicone for gastrointestinal endoscopy: Results of a clinical trial

During endoscopy, simethicone defoaming agents are commonly used to improve visualization, but they leave residues and impact drying. This clinical trial involved patients undergoing colonoscopy procedures with substantial bubbles that impeded mucosal wall visibility. As an alternative to simethicone, investigators evaluated a water-soluble, ginger-based gastrointestinal supplement (GI-Ease) that did not contain sugars, thickeners, or binding agents. In 112/114 cases (98%), the bubbles were reduced sufficiently to allow visualization of the gastrointestinal tract, with no adverse events.

Full-scale control of Mycolata foam by FEX-120 addition

Foaming incidents in activated sludge treatment plants are a worldwide problem and occur on a regular basis in both municipal and industrial activated sludge treatment plants. Foaming is most often caused by excessive growth of filamentous bacteria, especially the gram-positive ones affiliated within the Actinobacteria, e.g. the branched Mycolata or Candidatus Microthrix parvicella. Previous studies have shown that populations of Microthrix can be controlled by addition of certain polyaluminium compounds, but until now no effective chemicals have been identified to control other important foam formers such as the Mycolata. A new chemical (FilamentEx, FEX-120) was tested in full-scale in a Swedish wastewater treatment plant (WWTP) with immense foaming problems. In total, three different dosing events were carried out for more than 1 year. After only 8-17 weeks in each period, all foam had disappeared, and dosing of FEX-120 was stopped. Another 11 full-scale WWTPs in different countries were treated with FEX-120 because of severe Mycolata foaming on process tanks. In nine out of 11 plants, where the causative organisms were Gordonia or Skermania, a significant reduction of foam up to 100% was observed after treatment for approx. 10 weeks. In two WWTPs with unknown Mycolata organisms, no reduction was observed.

The role of simeticone in small-bowel preparation for capsule endoscopy

BACKGROUND AND STUDY AIMS

Capsule endoscopy is a new diagnostic method allowing painless visualization of the entire small bowel. However, there is as yet no standardized protocol for bowel preparation before the examination. The aim of this study was to assess the effectiveness of simeticone in reducing bowel gas bubbles in patients undergoing capsule endoscopy.

PATIENTS AND METHODS

A randomized, prospective, and controlled study was conducted, including 56 patients, from March to October 2004. The patients were randomly allocated to groups receiving either simeticone or no simeticone, on the basis of a computer-generated random number table. Patients in the simeticone group (n = 28) received 300 mg simeticone for bowel preparation 20 min before capsule endoscopy, while patients in the non-simeticone group (n = 28) received no medication for bowel preparation. Two experienced endoscopists assessed and graded the visibility of the mucosa and intraluminal gas bubbles in a single-blinded fashion.

RESULTS

The visibility of the mucosa in the proximal small bowel in patients who received preparation with simeticone was considered to be better, with fewer intraluminal bubbles, than in those without bowel preparation ( P < 0.025). Interobserver agreement was excellent ( R > or = 0.8, P < 0.05). No adverse effects of simeticone were observed.

CONCLUSIONS

Simeticone administration before capsule endoscopy improves the visualization of the mucosa in the proximal small intestine.

Therapy of paroxysmal pulmonary edema by antifoaming agents

Inhalation of certain volatile substances decreases the amount of foam in the respiratory passages and may be helpful in acute pulmonary edema. Experiments with several agents were performed in animals with different types of acute edema of the lungs. The best results were obtained with ethyl alcohol, which decreased the severity of the edema and prolonged the survival of the animals. Alcohol, while acting as an antifoaming agent, has no untoward side effects and is well tolerated. This method of therapy is now undergoing clinical tests.

Improved US visualization of the pancreatic tail with simethicone, water, and patient rotation

PURPOSE

To evaluate the effect of degassed water, simethicone, and patient rotation on ultrasonographic (US) visualization of the pancreatic tail.

MATERIALS AND METHODS

Seventy patients in whom visualization of the pancreatic tail was poor at US were reevaluated in the upright position after ingesting 2 cups (500 mL) of water with 80 mg of simethicone followed by rotating three times on the examination table. In a few patients, the right posterior oblique position was used. Pancreatic tail visualization and disbursement of gastric gas were evaluated. Seventy patients who received 500 mL of distilled water only served as control subjects.

RESULTS

Pancreatic tail visualization in patients versus control subjects was complete in 55 (79%) versus five (7%) of 70 patients and control subjects, partial in 10 (14%) versus 38 (54%), and not improved in five (7%) versus 27 (39%). The effect on diminishing gastric air was closely correlated with the degree of improved visualization in most patients. All patients tolerated the procedure well, with no side effects. The technique added a mean of 8 versus 5 minutes to the examination in patients versus control subjects. The full acoustic window effect of the simethicone-water mixture lasted approximately 10 minutes.

CONCLUSION

The simethicone-water-rotation technique is simple, safe, inexpensive, and effective for improving pancreatic tail visualization in ambulatory patients and is superior to the use of water alone.

Influence of formulation on jet nebulisation quality of alpha 1 protease inhibitor

As foam appears during solution constitution and nebulisation of alpha 1 protease inhibitor (alpha 1 PI), we selected in a previous work, antifoams likely to be associated with an alpha 1 PI solution to be nebulised: span 65 at a 0.025% concentration and cetyl alcohol at a 0.05% concentration associated with tyloxapol at 0.025% concentration. The purpose of this study was, on the one hand to study the influence of the formulation on nebulisation quality by relating physicochemical properties and nebulisation capacity, and on the other hand, to define the alpha 1 PI that will be retained for a clinical study. The properties of the different alpha 1 PI formulations are compared: surface tension, viscosity, time required to constitute the protein solution and pH. Nebulisation quality is evaluated under different operating conditions by measuring the droplet size, the quantity of alpha 1 PI nebulised, nebulisation time and the quantity of alpha 1 PI likely to reach the lungs which was subjected to statistical analysis. The statistical analysis of results indicates that the addition of the cetyl alcohol/tyloxapol mixture improves nebulisation effectiveness by significantly increasing the quantity of drug nebulised and therefore the quantity of alpha PI likely to reach the lungs. It is this formulation that will be retained for clinical trials. We check that the nebuliser and operating conditions influence all the parameters, that is to say the respirable fraction, the quantity nebulised and the nebulisation time. Although there is no interaction between the nebuliser and the formulation, nebulisation quality is the combined result of the formulation, the nebuliser and the operating conditions.

Quantitative investigations of cell-bubble interactions using a foam fractionation technique

Previous work by the authors and others has shown that suspended animal cell damage in bioreactors is caused by cell-bubble interactions, regardless whether the bubbles are from bubble entrainment or direct gas sparging. As approach to measure the adsorptivity of animal cells to bubbles, a modified batch foam fractionation technique has been developed in this work and proven to be applicable. By using this technique, the number of cells absorbed per unit bubble surface area and the adsorption coefficients have been measured to quantify hybridoma cell-bubble interactions, and the preventive effects of serum and Pluronic F68 on these interactions. It was demonstrated quantitatively that the hybridoma cells adhere to bubbles spontaneously and significant numbers exist in the foam, and that both the serum and Pluronic F68 provide strong prevention to these cell-bubble interactions. The results obtained provide criteria for bioreactor operation and medium formulation to prevent cell-bubble interactions and cell damage in the culture processes.

High cell density suspension culture of mammalian anchorage independent cells: Oxygen transfer by gas sparging and defoaming with a hydrophobic net

Gas sparging directly into the culture-broth is not done in cell culture, except when the gas flow rate is very small, because much foaming occurs. During screening of defoaming methods, foam was observed to be broken up effectively when it made contact with a net fabricated from hydrophobic materials. Providing a highly efficient oxygen supply to suspension culture was tried using the new defoaming method. In a 5 l reactor equipped with the foam-eliminating net fabricated with polysiloxane, oxygen was transferred at 21 mmole/l.h equivalent to a consumption rate of 1 X 10(8) cells/ml, even at a low oxygen gas flow rate of 0.1 cm/s corresponding to a fourth of the gas flow rate when foam leaked through the net. Perfusion culture of rat ascites hepatoma cell JTC-1 was successfully carried out in the 5 l scale culture system with the net and a hydrophobic membrane for cell filtration. The viable cell concentration reached 2.7 X 10(7) cells/ml after twenty-seven days, in spite of the nutrient-deficient condition of the lower medium exchange rate, that is, a working volume a day, and viability was maintained at more than 90%. In a 1.21 scale culture of mouse-mouse hybridoma cell STK-1, viable cell concentration reached 4 X 10(7) cells/ml. These results showed that oxygen transfer by gas sparging with defoaming was useful for high density suspension culture. A foam-breaking mechanism was proposed.

A low-cost antifoam additive for agar-based culture media

A highly effective, low-cost silicone-based antifoam emulsion is described which, at a final concentration of 100 ppm, prevents bubble formation during the preparation and dispensing of agar media. The compound is heat-stable, has a long shelf-life and offers considerable savings in cost by reduction in wastage of time and materials. It has no demonstrable deleterious effect on the growth of a wide range of pathogenic and commensal bacteria, or on antibiotic disc susceptibility testing, when examined using a range of different media.

Double contrast preparations: an in vitro study of some antifoaming agents

An apparatus is described for the study of foam formation in double contrast preparations in vitro. Antifoaming agents are shown to be of considerable benefit to the double contrast technique, silicone and silicone-free antifoamers being equally effective. Silicone antifoamers are preferred because of their wide clinical acceptability. Antifoamer formulation and concentration are found to be critical factors in determining efficacy of foam suppression, and may lead to erroneous results in the clinic.

Further studies with antifoaming agents in experimental pulmonary edema

The effect of several antifoaming agents by inhalation in preventing paroxysmal pulmonary edema was tested in a series of rabbits. Three single agents (silicone aerosol, freon, and ethyl alcohol vapor) proved beneficial; their combination did not enhance the beneficial effect. A new agent (silicone aerosol) and a new combination (10 per cent ether in alcohol by aerosol) are now ready for clinical trial.