The acidity index: a simple approach to the measurement of gastric acidity

A universal method for determining the detergent effect of surfactants

Surfactants are indispensable in industrial applications today due to their wetting, emulsifying, dispersing, cleansing, and detergent properties. The use of surfactants extends from the cosmetic industry to the petroleum industry and beyond. Their characteristics and effectiveness can be assessed through various standardized tests, and based on these methods, their applications can be determined. However, there is a lack of a universally applicable testing method for one crucial and complex property: the detergent effect. The detergent effect refers to the removal of unwanted contaminants from a solid surface. However, cleaning is not solely attributed to the surfactant but to the appropriate combination of various factors, whose synergistic effect reduces surface contamination. The most significant factors influencing detergent effect include the characteristics and nature of the contaminants, properties of the cleaning solution (surfactant concentration and composition, water hardness, enzymes, etc.), temperature, washing time, and hydrodynamic conditions. Additionally, the presence of electrolytes, pH of the cleaning solution, and detergent foaming properties may also play important roles. Our goal was to develop a detergent effect testing methodology that is not specific to any particular application domain but offers a straightforward and easy-to-implement solution for comparing the detergent effect of various types of surfactants.•The study presents a method for determining detergent effect of surfactants.•The method is universal and suitable for the evaluation of any type of surfactant.•The method is low-cost and easy to perform.

The safety, pharmacodynamics, and pharmacokinetics of immediate-release formulation containing esomeprazole 20 mg/sodium bicarbonate 800 mg in healthy adult male

Background

Esomeprazole is the most effective treatment for acid-related disorders and is widely used with enteric coating due to rapid degradation in the acidic environment. However, the enteric-coated formulation delays absorption and onset of action. To overcome this limitation, an immediate-release formulation containing esomeprazole 20 mg and sodium bicarbonate 800 mg (IR-ESO) was developed.

Purpose

To evaluate the safety, pharmacokinetics (PK), and pharmacodynamics of IR-ESO compared to those of esomeprazole 20 mg (ESO).

Methods

A randomized, open-label, multiple-dose, two-treatment, two-sequence crossover study was conducted in 40 healthy male subjects. Subjects received either IR-ESO or ESO for 7 days. After single and multiple dosing, blood samples were collected for PK analysis, and intragastric pH was assessed by 24-hr pH monitoring.

Results

Plasma esomeprazole exposure of IR-ESO was similar to that of ESO after single and multiple dosing. Time to peak concentration of IR-ESO (0.50–0.75 hr) was shorter than that of ESO (1.25–1.50 hr). Percentage changes in 24-hr integrated gastric acidity from baseline for IR-ESO were similar to those for ESO. In addition, mean time to maintain gastric pH >4 for 24 hr was similar for both drugs (IR-ESO 55.5–69.9% vs ESO 56.8–70.2%). Evaluation of time to first reach pH 4 after dosing indicated that IR-ESO showed a faster onset than ESO. All subjects found the drug tolerable, and there were no significant differences in adverse events between two drugs.

Conclusion

This study showed that IR-ESO produced a rapid, safe and sustained gastric acid suppression (ClinicalTrials.gov: NCT03211143).

Sporadic Fundic Gland Polyps and Gastric Acid Suppression Level

BACKGROUND

Fundic gland polyps (FGPs) are a common endoscopic finding and are known to be associated with proton pump inhibitors (PPIs) use. It is not known if their prevalence is affected by gastric acidity levels. This study aimed to assess whether there is a correlation between FGPs and gastric acidity levels as identified on 24-hour ambulatory impedance-pH studies in patients on PPI therapy.

METHODS

We performed a review of 402 consecutive patients who take at least once daily PPI and underwent esophagogastroduodenoscopy with combined impedance-pH studies in the same setting (time and place) between January 2010 and December 2014. Patients were classified into 2 groups based on the presence or absence of biopsy-confirmed FGPs during endoscopy.

RESULTS

Of the 402 patients, 30 (7%) had FGPs. One of these polyps was found with low-grade dysplasia. There was no significant difference of the distributions of the [H⁺] in the FGPs versus the nonpolyp groups (P = 0.741). There was no significant difference between the 2 groups regarding PPI dose frequency regimens (once and twice) (P = 0.074). However, we found weak ordinal association with PPI duration (P = 0.01) (Spearman = 0.1).

CONCLUSIONS

FGPs are common endoscopic lesions. Incidence of dysplasia in FGPs is not only rare, but also of unknown clinical significance. Although they seem to be associated with PPIs, the mechanism remains unclear, as we found no correlation between the presence of FGPs and gastric acid control or PPI dose. Future studies would be useful to elucidate an alternate mechanism.

Functional Profile Evaluation of Lactobacillus fermentum TCUESC01: A New Potential Probiotic Strain Isolated during Cocoa Fermentation

The use of intestinal probiotic bacteria is very common in the food industry and has been the focus of the majority of research in this field. Yet in recent years, research on extraintestinal microorganisms has greatly increased due to their well-known potential as probiotics. Thus, we studied a strain of Lactobacillus fermentum (TCUESC01) extracted from fermenting cocoa. First, we examined the impact of pH on the growth of this strain and studied its survival under conditions similar to those of the human gastrointestinal tract. L. fermentum TCUESC01 demonstrated resistance to conditions mimicking the human stomach and intestines and grew well between pH 5 and pH 7. Next, we subjected L. fermentum TCUESC01 to storage at 4°C in a milk solution and found that it survived well for 28 days. Lastly, we measured the susceptibility of this strain to numerous antibiotics and its tendency to autoaggregate. L. fermentum TCUESC01 showed significant autoaggregation, as well as susceptibility to the majority of antibiotics tested. Overall, our findings support the potential use of this extraintestinal bacterium as a dietary probiotic.

Oral rabeprazole vs. intravenous pantoprazole: a comparison of the effect on intragastric pH in healthy subjects

BACKGROUND

Intravenous pantoprazole is often administered inappropriately to hospitalized patients who can take oral medications.

AIM

To compare the antisecretory effects of oral rabeprazole and intravenous pantoprazole in healthy subjects.

METHODS

In a double-blind, double-dummy, two-way crossover study, 38 Helicobacter pylori-negative volunteers were randomized to oral rabeprazole 20 mg or intravenous pantoprazole 40 mg daily for 3 days followed, after a 14-day washout period by the comparator treatment. Intragastric pH was recorded continuously for 24 h at baseline and on days 1 and 3 of each treatment period.

RESULTS

The mean (95% CI) percentage of the 24-h recording with gastric pH >4 was higher with rabeprazole than with pantoprazole on day 1: 37.7% (30.6-44.8%) vs. 23.9% (20.0-27.8). The mean percentage times with pH >3 and >4 for all intervals assessed were greater and the median 24-h intragastric pH values were higher with rabeprazole than with pantoprazole on days 1 and 3. The mean acidity index was lower with rabeprazole on days 1 and 3.

CONCLUSIONS

Oral rabeprazole 20 mg produced greater acid suppression than intravenous pantoprazole 40 mg. Therefore, it may be an appropriate and effective alternative in patients who can take oral medication.

Analysis of the acidity index and integrated intragastric acidity in 645 patients presenting with gastroesophageal reflux disease symptoms

OBJECTIVE

In a recent study of patients receiving proton-pump inhibitor (PPI) therapy, a new parameter, the acidity index, was described as being less complicated to calculate and of comparable accuracy (r = 0.93) to integrated intragastric acidity (IA) in assessing intragastric pH control. The aim of this study was to correlate AI with IA using a large database of ambulatory 24-h pH-metry studies in untreated patients presenting with gastroesophageal reflux disease (GERD) symptoms.

MATERIAL AND METHODS

We retrospectively analyzed 645 studies obtained from 1995 to 2001. Daytime (0800 h-2200 h), night-time (2200 h-0800 h) and 24-h IA and AI were calculated according to age, gender and the presence or absence of GERD, and correlations between these parameters were assessed using linear regression with F-statistic values, p-values and Akaike's Information Criterion values. GERD was defined as total esophageal pH time <4.0, 5 cm above the lower esophageal sphincter, for > or =4.2% of the day. IA and AI were calculated as follows: IA (mmol x h/l) = summation operator(acid in mmol/l at time "t" + acid in mmol/l at time "t - 1")/2 x ("t"-"t - 1"); AI = (%time pH < 4-%time pH < 3) x 1+(%time pH < 3-%time pH < 2) x 10+(%time pH < 2-%time pH < 1) x 100 + (%time pH < 1-%time pH < 0.8) x 1000.

RESULTS

Overall, the mean 24-h IA value was 882.0+/-820.0 mmol x h/l (daytime 392.0+/-400.0, night-time 490.0+/-486.0). The mean 24-h AI value was 102.0+/-87.0 (daytime 86.0+/-80.0, night-time 120.0+/-114.0, p < 0.001). The mean 24-h IA value was 1057.0+/-829.4 mmol x h/l (daytime 459.8+/-406.0, night-time 597.2+/-500.4, p < 0.001) in GERD patients and 713.0+/-775.0 mmol x h/l (daytime 326.0+/-383.0, night-time 387.0+/-448.5) in non-GERD patients (p < 0.001). The mean 24-h AI value was 122.1+/-88.1 (daytime 101.4+/-82.5, night-time 145.3+/-120.7) in GERD patients and 83.0+/-81.0 (daytime 71.0+/-73.9, night-time 96.4+/-102.6) in non-GERD patients (p < 0.001). Our statistical modeling demonstrated that the correlation between the acidity index and IA becomes progressively poorer with increasing values of acidity.

CONCLUSIONS

We conclude that gastric acid production assessed by both IA and AI is higher during evening hours in comparison with daytime hours and the difference between night-time and daytime values is statistically significant. In addition, gastric acid production assessed by both IA and AI is significantly higher in GERD patients than non-GERD patients. This difference is primarily due to differences in nocturnal acid production. The AI correlates poorly with measured IA, especially at higher levels of gastric acidity. Therefore, AI is not an acceptable surrogate for IA in assessing gastric acid production.

Proton pump inhibitor formulary considerations in the acutely ill. Part 1: Pharmacology, pharmacodynamics, and available formulations

OBJECTIVE

To review important proton pump inhibitor (PPI) pharmacologic, pharmacokinetic, and pharmacodynamic principles in acutely ill patients, compare PPI formulation options for patients unable to swallow a tablet or capsule, and provide clinicians with guidance when making hospital formulary decisions with this class of agents.

DATA SOURCES

MEDLINE (1966-May 2005) and the Cochrane Library databases were searched using the key words proton pump inhibitor, acid suppression, peptic ulcer disease, gastrointestinal bleeding, stress ulcer prophylaxis, and critical illness. Bibliographies of cited references were reviewed, and a manual search of abstracts from recent gastroenterology, critical care, and surgery scientific meetings was completed.

STUDY SELECTION AND DATA EXTRACTION

All articles identified from the data sources were evaluated, and all information deemed relevant was included for this review.

DATA SYNTHESIS

PPIs have become a mainstay for acute acid suppression in hospitalized patients over other therapeutic options. Various commercially available PPI products are available for administration, either enterally or parenterally, to patients unable to swallow a tablet or capsule. Newer oral PPI formulations offer numerous advantages over older products. The results of studies comparing the pharmacokinetics and pharmacodynamics of different PPI dosage forms and routes of administration are among the factors to consider when making formulary decisions.

CONCLUSIONS

While the introduction of new PPI products has expanded the therapeutic options for acid suppression in acutely ill patients, a number of unresolved questions remain surrounding the interchangeability of these products, the clinical significance of one PPI formulation over the other, and how oral/enteral PPI therapy should be used as step-down therapy after parenteral PPI therapy.