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"Hydrogen-Ion Concentration - drug effects"
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Association of Urinary Citrate With Acid-Base Status, Bone Resorption, and Calcium Excretion in Older Men and Women
by
Dawson-Hughes, Bess
,
Shea, M Kyla
in
Acid-Base Equilibrium - drug effects
,
Acid-Base Equilibrium - physiology
,
Acid-base status
2018
Abstract
Context
Elevated urine net acid excretion (NAE), indicative of subclinical metabolic acidosis, has been associated with higher bone turnover. Urine citrate, which is a common clinical measure, changes in response to acid-base status but its association with bone turnover is uncertain.
Objective
We evaluated the association between change in urine citrate and change in bone turnover and calcium excretion.
Design, Intervention, and Participants
A total of 233 healthy men and women ≥60 years old were randomly assigned to 1.0 mmol/kg/d potassium bicarbonate (KHCO3), 1.5 mmol/kg/d KHCO3, or placebo for 84 days.
Outcome Measures
Urine citrate, NAE, N-telopeptide of collagen type-I (NTX), calcium excretion, and serum amino-terminal propeptide of type 1 procollagen (P1NP) were measured before and after intervention.
Results
Urine citrate increased dose dependently after KHCO3 supplementation (P trend < 0.001). The urine citrate change was significantly inversely associated with P1NP change (P = 0.021) but not with change in NTX (P = 0.051) or calcium excretion (P = 0.652). The NAE change was positively associated with change in NTX and calcium excretion (P ≤ 0.003) but not with change in P1NP (P = 0.051). When the urine citrate change and NAE change were included in the same model, the urine citrate change was not associated with change in NTX, calcium excretion, or serum P1NP (P ≥ 0.086), whereas change in NAE remained associated with change in NTX and calcium excretion (P ≤ 0.003).
Conclusion
Urine citrate may not be a suitable alternative to NAE when assessing acid-base status in relation to bone turnover in older adults.
In older adults, urine citrate excretion increased in response to alkali supplementation, but the change in urine citrate was not a robust indicator of change in bone resorption or calcium excretion.
Journal Article
Coconut Water: An Unexpected Source of Urinary Citrate
by
Patel, Roshan M.
,
Clayman, Ralph V.
,
Okhunov, Zhamshid
in
Adult
,
Alkalies - chemistry
,
Analysis
2018
Purpose. Coconut water has long been touted for its medicinal qualities including natural hydration. We sought to determine whether its consumption would induce changes to urinary lithogenic factors beyond changes in urine volume. Materials and Methods. After Institutional Review Board approval, volunteers with no prior history of nephrolithiasis were recruited. Each participant was randomized initially to either the coconut water or the water phase of the study. Participants kept meticulous food and fluid intake logs during the first phase of the study and were asked to replicate that diet for the second phase. For each phase the participant consumed 2L of either Taste of Nirvana® pure coconut water or tap water daily for four days. Participants were not restricted to consume additional fluid of their choice during their assigned study phase. During days 3 and 4 of each phase the participant collected a 24-hour urine specimen. Coconut water citrate and malate content were measured and were used along with the beverage pH to calculate the total alkali content of the coconut water. Supersaturation levels were calculated using Equil2. Nonparametric paired analysis using the Wilcoxon test was performed for statistical analysis. Results. There were 4 adult male and 4 adult female participants. Each individual’s 24-hour urine collection had a creatinine excretion within 20% of the mean for each subject’s four samples corroborating that all samples were collected properly. The two samples from each phase for each individual were averaged. The coconut water itself was also analyzed and it was calculated to have a total alkali content of 13.8 mEq/L. Consumption of coconut water significantly increased urinary citrate (29%, p=0.02), urinary potassium (130%, p=0.01), and urinary chloride (37%, p=0.03), without affecting urine pH (p=0.16) or volume beyond that of tap water (p=1.00). Conclusions. Coconut water consumption increases urinary potassium, chloride, and citrate in nonstone forming individuals.
Journal Article
The negative effect of unloading exceeds the bone-sparing effect of alkaline supplementation: a bed rest study
2019
SummaryPotassium bicarbonate was administrated to an already alkaline diet in seven male subjects during a 21-day bed rest study and was able to decrease bed rest induced increased calcium excretion but failed to prevent bed rest-induced bone resorption.IntroductionSupplementation with alkali salts appears to positively influence calcium and bone metabolism and, thus, could be a countermeasure for population groups with an increased risk for bone loss. However, the extent to which alkalization counteracts acid-induced bone resorption or whether it merely has a calcium and bone maintenance effect is still not completely understood. In the present study, we hypothesized that additional alkalization to an already alkaline diet can further counteract bed rest-induced bone loss.MethodsSeven healthy male subjects completed two parts of a crossover designed 21-day bed rest study: bed rest only (control) and bed rest supplemented with 90 mmol potassium bicarbonate (KHCO3) daily.ResultsKHCO3supplementation during bed rest resulted in a more alkaline status compared to the control intervention, demonstrated by the increase in pH and buffer capacity level (pH p = 0.023, HCO3p = 0.02, ABE p = 0.03). Urinary calcium excretion was decreased during KHCO3 supplementation (control 6.05 ± 2.74 mmol/24 h; KHCO3 4.87 ± 2.21 mmol/24 h, p = 0.03); whereas, bone formation was not affected by additional alkalization (bAP p = 0.58; PINP p = 0.60). Bone resorption marker UCTX tended to be lower during alkaline supplementation (UCTX p = 0.16).ConclusionsThe more alkaline acid-base status, achieved by KHCO3 supplementation, reduced renal calcium excretion during bed rest, but was not able to prevent immobilization-induced bone resorption. However, advantages of alkaline salts on bone metabolism may occur under acidic metabolic conditions or with respect to the positive effect of reduced calcium excretion within a longer time frame.Trial registrationTrial number: NCT01509456
Journal Article
A randomized trial comparing prophylactic phenylephrine and ephedrine infusion during spinal anesthesia for emergency cesarean delivery in cases of acute fetal compromise
by
Makkar, Jeetinder Kaur
,
Gander, Shalini
,
Jain, Kajal
in
Acidosis - chemically induced
,
Adult
,
Anesthesia
2016
Previous evidence showed that use of phenylephrine was associated with higher umbilical artery pH (UA pH) than ephedrine after elective cesarean delivery (CD). However, the best choice of vasopressor and its effect on funic gases in cases of acute fetal compromise require additional studies.
Ninety parturients showing acute fetal compromise during intrapartum period and taken up for CD (category II) under spinal anesthesia were randomized to receive prophylactic infusion of ephedrine 2.5mg/min or phenylephrine 30μg/min. Systolic blood pressure was targeted between 90% and 110% of baseline. Incidence of fetal acidosis (UA pH <7.2 and/or base deficit >12mmol/L) was recorded. Other parameters of cord gases, Apgar score, need for immediate resuscitation, maternal hemodynamics, and adverse events were also compared.
Number of neonates showing acidosis with ephedrine or phenylephrine was comparable (P=.22). Of these, newborns with base deficit >12mmol had low 1-minute Apgar scores (n=15/23). The ephedrine group had higher oxygen content in UA (P=.03). There was no adverse neonatal outcome during the period of observation. Incidence of maternal nausea and vomiting was higher with ephedrine than with phenylephrine (22.2% vs 4.4%; P=.02). Maternal bradycardia was observed with phenylephrine (P=.02).
Our data report similar fetal acidosis with either phenylephrine or ephedrine administered during spinal anesthesia for treating maternal hypotension in cases of emergency CD.
•Fetal acidosis has been reported after spinal anesthesia.•Maintaining baseline blood pressure results in best neonatal outcome in elective CD.•Only retrospective data are available for CD indicated for acute fetal compromise.•We report fetal acidosis using vasopressor during CD for acute fetal compromise.
Journal Article
Effectiveness of casein phosphopeptide-amorphous calcium phosphate and xylitol chewing gums on salivary pH, buffer capacity, and Streptococcus mutans levels: An interventional study
by
Padminee, Krishnan
,
Srinivasan, Manali
,
Duraivel, Dasarathan
in
Antibiotics
,
Anticariogenic efficacy
,
Calcium phosphates
2018
Aim: The aim of the study is to compare the anticariogenic effectiveness of Casein phosphopeptide- Amorphous Calcium phosphate (CPP-ACP) and xylitol chewing gums based on salivary pH, buffer capacity, and Streptococcus mutans levels. Materials and Methods: A group of twenty individuals in the age group of 18-25 years were randomly divided into two Groups A and B. Test arm A received xylitol gums and test arm B received CPP-ACP gums and they were instructed to use the gums thrice daily for 2 weeks. Unstimulated salivary samples were collected before they began the use of the gums for baseline values, 24 h after beginning the usage of chewing gums and at the end of 14 days. The samples were analyzed for pH, buffer capacity, and S. mutans levels. Results: A statistically significant reduction of salivary S. mutans levels, improvement in salivary pH, and buffer capacity were displayed in both groups 24 h and 14 days after the intervention when compared with baseline. Group B showed more statistically significant improvement in pH than group A after 24 h (P = 0.028) and at the end of 2 weeks (P = 0.041). Conclusion: CPP-ACP has better ability than xylitol in improving the pH of saliva. Both CPP-ACP and xylitol gums individually have remarkable ability in bringing down S. mutans levels while simultaneously improving the pH and buffer of saliva.
Journal Article
Bioequivalence of a Newly Developed Dabigatran Etexilate Tablet Versus the Commercial Capsule and Impact of Rabeprazole-Induced Elevated Gastric pH on Exposure in Healthy Subjects
2020
Background and Objective
Dabigatran etexilate (DE) is an anticoagulant with proven efficacy and tolerability for stroke prevention in patients with non-valvular atrial fibrillation. For the commercial capsule, a complex formulation is used to maintain the acidic microenvironment required for maximal absorption. Consequently, its efficacy and safety are similar with or without concomitant intake of proton-pump inhibitors (PPIs). A simplified DE tablet formulation was developed and tested in two studies. One investigated bioequivalence (BE) of the novel DE tablet versus the commercial DE capsule. The other investigated DE bioavailability (BA) under pretreatment with the PPI rabeprazole and assessed the effect of elevated pH on exposure to dabigatran.
Methods
BE of the novel DE tablet versus the DE capsule was assessed in a randomized two-treatment, four-period, two-sequence crossover study (NCT03070171). The effect of rabeprazole on the BA of the DE tablet was assessed in an open-label, single-arm study (NCT03143166). Both studies were conducted at sites in Japan. Participants were healthy male volunteers, aged ≥ 20–40 years. In the BE study, participants received the DE tablet or capsule (single oral dose, 110 mg); primary endpoints were area under the concentration–time curve from baseline to the last quantifiable data point (AUC
0–tz
) and maximum plasma concentration (
C
max
) of unconjugated dabigatran. In the relative BA study, participants received the DE tablet (single oral dose, 110 mg) with or without rabeprazole pretreatment (once daily for 5 days, 20 mg); primary endpoints were AUC
0–tz
and
C
max
of total dabigatran.
Results
In total, 160 participants were randomized in the BE study; 36 participants were enrolled in the BA study. The 90% confidence intervals of geometric mean (gMean) ratios for AUC
0–tz
(101.4–116.0%) and
C
max
(101.8–116.6%) of unconjugated dabigatran were within pre-defined acceptance criteria for BE. In the relative BA study, the gMeans of AUC
0–tz
(667 to 192 ng h/mL) and
C
max
(83.1 to 21.8 ng/mL) were decreased by approximately 70% when the tablet was administered under rabeprazole pretreatment. The reduction in BA was observed at a mean gastric pH of 5.3. Treatment was well tolerated; no deaths, serious adverse events (AEs) or significant AEs were reported in either study.
Conclusion
The DE tablet demonstrated BE to the capsule; however, at high gastric pH, BA of the tablet was reduced by approximately 70%, which may lead to reduced efficacy. Data indicate the importance of examining not only BE under standard conditions, but relative BA at elevated gastric pH. Such investigations may avoid the reduced BA at elevated pH that is quite common in the target population (the elderly and/or patients treated with gastric-acid modifying co-medications), and therefore reduce treatment failure with DE.
Registration: ClinicalTrials.gov identifier numbers: NCT03070171, and NCT03143166
Journal Article
Volume, distribution and acidity of gastric secretion on and off proton pump inhibitor treatment: a randomized double-blind controlled study in patients with gastro-esophageal reflux disease (GERD) and healthy subjects
by
Liu, Dian
,
Fox, Mark
,
Schwizer, Werner
in
2-Pyridinylmethylsulfinylbenzimidazoles - administration & dosage
,
2-Pyridinylmethylsulfinylbenzimidazoles - therapeutic use
,
Adolescent
2015
Background
Postprandial accumulation of gastric secretions in the proximal stomach above the meal adjacent to the esophagogastric junction (EGJ), referred to as the ‘acid pocket’, has been proposed as a pathophysiological factor in gastro-esophageal reflux disease (GERD) and as a target for GERD treatment. This study assessed the effect of proton pump inhibitor (PPI) therapy on the volume, distribution and acidity of gastric secretions in GERD and healthy subjects (HS).
Methods
A randomized, double blind, cross-over study in 12 HS and 12 GERD patients pre-treated with 40 mg pantoprazole (PPI) or placebo b.i.d. was performed. Postprandial secretion volume (SV), formation of a secretion layer and contact between the layer and the EGJ were quantified by Magnetic Resonance Imaging (MRI). Multi-channel pH-monitoring assessed intragastric pH.
Results
A distinct layer of undiluted acid secretion was present on top of gastric contents in almost all participants on and off high-dose acid suppression. PPI reduced SV (193 ml to 100 ml, in HS, 227 ml to 94 ml in GERD; p < 0.01) and thickness of the acid layer (26 mm to 7 mm, 36 mm to 9 mm respectively, p < 0.01). No differences in secretion volume or layer thickness were observed between groups; however, off treatment, contact time between the secretion layer and EGJ was 2.6 times longer in GERD compared to HS (p = 0.012). This was not the case on PPI.
Conclusions
MRI can visualize and quantify the volume and distribution dynamics of gastric secretions that form a layer in the proximal stomach after ingestion of a liquid meal. The secretion volume and the secretion layer on top of gastric contents is similar in GERD patients and HS; however contact between the layer of undiluted secretion and the EGJ is prolonged in patients. High dose PPI reduced secretion volume by about 50 % and reduced contact time between secretion and EGJ towards normal levels.
Trial registration
NCT01212614
.
Journal Article
Effect on skin hydration of using baby wipes to clean the napkin area of newborn babies: assessor-blinded randomised controlled equivalence trial
2012
Background
Some national guidelines recommend the use of water alone for napkin cleansing. Yet, there is a readiness, amongst many parents, to use baby wipes. Evidence from randomised controlled trials, of the effect of baby wipes on newborn skin integrity is lacking. We conducted a study to examine the hypothesis that the use of a specifically formulated cleansing wipe on the napkin area of newborn infants (<1 month) has an equivalent effect on skin hydration when compared with using cotton wool and water (usual care).
Methods
A prospective, assessor-blinded, randomised controlled equivalence trial was conducted during 2010. Healthy, term babies (n = 280), recruited within 48 hours of birth, were randomly assigned to have their napkin area cleansed with an alcohol-free baby wipe (140 babies) or cotton wool and water (140 babies). Primary outcome was change in hydration from within 48 hours of birth to 4 weeks post-birth. Secondary outcomes comprised changes in trans-epidermal water loss, skin surface pH and erythema, presence of microbial skin contaminants/irritants at 4 weeks and napkin dermatitis reported by midwife at 4 weeks and mother during the 4 weeks.
Results
Complete hydration data were obtained for 254 (90.7 %) babies. Wipes were shown to be equivalent to water and cotton wool in terms of skin hydration (intention-to-treat analysis: wipes 65.4 (SD 12.4) vs. water 63.5 (14.2), p = 0.47, 95 % CI -2.5 to 4.2; per protocol analysis: wipes 64.6 (12.4) vs. water 63.6 (14.3), p = 0.53, 95 % CI -2.4 to 4.2). No significant differences were found in the secondary outcomes, except for maternal-reported napkin dermatitis, which was higher in the water group (p = 0.025 for complete responses).
Conclusions
Baby wipes had an equivalent effect on skin hydration when compared with cotton wool and water. We found no evidence of any adverse effects of using these wipes. These findings offer reassurance to parents who choose to use baby wipes and to health professionals who support their use.
Trial registration
Current Controlled Trials ISRCTN86207019
Journal Article
A comparative evaluation of the anticaries efficacy of herbal extracts (Tulsi and Black myrobalans) and sodium fluoride as mouthrinses in children: A randomized controlled trial
by
Sajeev, R
,
Ramesh, V
,
Vargeese, Abhishek
in
Acids
,
Antibacterial agents
,
Antimicrobial agents
2018
Background: Dental caries is a multifactorial disease in which microorganisms play an important role. Recently, herbs have been tried as mouthrinses to combat the side effects of chemical mouthrinses. The anticaries efficacy of Sodium fluoride, Tulsi leaf, and Black myrobalans fruit extracts on Streptococcus mutans (S. mutans) have been reported in the literature, but no comparative study has been done yet. Aim: This study aims to observe the change in the pH of saliva and to assess the efficacy of the herbal rinses-Tulsi and Black myrobalans on S. mutans count while comparing it with Sodium fluoride mouthrinse. Methods: Herbal ethanolic extracts of Tulsi (4%) and Black myrobalans (2.5%) were prepared as mouthrinses and compared with sodium fluoride mouthrinse (0.05%). Sixty high caries risk patients were selected and allocated randomly into three groups [n = 20], categorized as Group A-Sodium fluoride mouthrinse, Group B-Tulsi mouthrinse, and Group C-Black myrobalans mouthrinse. They were instructed to rinse their mouth with their assigned mouthrinses for 7 days. Salivary samples were collected and sent to the laboratory at baseline, 1 h postrinsing and after 7th day of rinsing for determining the salivary pH and S. mutans count. The increase in pH and reduction of S. mutans were determined. The values obtained were tabulated and statistically analyzed. Results: There was a significant increase in the salivary pH and reduction in S. mutans count after rinsing in all the three groups. Increase in salivary pH was more in the Sodium fluoride mouthrinse when compared to the experimental herbal groups (Group B and Group C). While S. mutans counts reduced more with Tulsi mouthrinse at 1 h postrinsing and after the 7th day of rinsing more reduction was seen in Black myrobalans mouthrinse group. Conclusion: The results of the study suggest that herbal mouthrinses could be tried as an adjunctive anticaries agent against dental caries causing microorganisms.
Journal Article
Control of transient lower oesophageal sphincter relaxations and reflux by the GABA(B) agonist baclofen in patients with gastro-oesophageal reflux disease
2002
Transient lower oesophageal sphincter relaxations (TLOSRs) are the major cause of gastro-oesophageal reflux in normal subjects and in most patients with reflux disease. The gamma aminobutyric acid (GABA) receptor type B agonist, baclofen, is a potent inhibitor of TLOSRs in normal subjects. The aim of this study was to investigate the effect of baclofen on TLOSRs and postprandial gastro-oesophageal reflux in patients with reflux disease.
In 20 patients with reflux disease, oesophageal motility and pH were measured, with patients in the sitting position, for three hours after a 3000 kJ mixed nutrient meal. On separate days at least one week apart, 40 mg oral baclofen or placebo was given 90 minutes before the meal.
Baclofen reduced the rate of TLOSRs by 40% from 15 (13.8-18.3) to 9 (5.8-13.3) per three hours (p<0.0002) and increased basal lower oesophageal sphincter pressure. Baclofen also significantly reduced the rate of reflux episodes by 43% from 7.0 (4.0-12.0) to 4.0 (1.5-9) per three hours (median (interquartile range); p<0.02). However, baclofen had no effect on oesophageal acid exposure (baclofen 4.9% (1.7-12.4) v placebo 5.0% (2.7-15.5)).
In patients with reflux disease, the GABA(B) agonist baclofen significantly inhibits gastro-oesophageal reflux episodes by inhibition of TLOSRs. These findings suggest that GABA(B) agonists may be useful as therapeutic agents for the management of reflux disease.
Journal Article