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The effects of two different doses of calcium lactate on blood pH, bicarbonate, and repeated high-intensity exercise performance.
Painelli, Vde S, da Silva, RP, de Oliveira, OM, de Oliveira, LF, Benatti, FB, Rabelo, T, Guilherme, JP, Lancha, AH, Artioli, GG
International journal of sport nutrition and exercise metabolism. 2014;(3):286-95
Abstract
We investigated the effects of low- and high-dose calcium lactate supplementation on blood pH and bicarbonate (Study A) and on repeated high-intensity performance (Study B). In Study A, 10 young, physically active men (age: 24 ± 2.5 years; weight: 79.2 ± 9.45 kg; height: 1.79 ± 0.06 m) were assigned to acutely receive three different treatments, in a crossover fashion: high-dose calcium lactate (HD: 300 mg · kg(-1) body mass), low-dose calcium lactate (LD: 150 mg · kg(-1) body mass) and placebo (PL). During each visit, participants received one of these treatments and were assessed for blood pH and bicarbonate 0, 60, 90, 120, 150, 180, and 240 min following ingestion. In Study B, 12 young male participants (age: 26 ± 4.5 years; weight: 82.0 ± 11.0 kg; height: 1.81 ± 0.07 m) received the same treatments of Study A. Ninety minutes after ingestion, participants underwent 3 bouts of the upper-body Wingate test and were assessed for blood pH and bicarbonate 0 and 90 min following ingestion and immediately after exercise. In Study A, both HD and LD promoted slight but significant increases in blood bicarbonate (31.47 ± 1.57 and 31.69 ± 1.04 mmol · L(-1, respectively) and pH levels (7.36 ± 0.02 and 7.36 ± 0.01, respectively), with no effect of PL. In Study B, total work done, peak power, mean power output were not affected by treatments. In conclusion, low- and high-dose calcium lactate supplementation induced similar, yet very discrete, increases in blood pH and bicarbonate, which were not sufficiently large to improve repeated high-intensity performance.
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Comparison of acetate-free citrate hemodialysis and bicarbonate hemodialysis regarding the effect of intra-dialysis hypotension and post-dialysis malaise.
Daimon, S, Dan, K, Kawano, M
Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy. 2011;(5):460-5
Abstract
Compared with acetate dialysate, bicarbonate dialysate has shown beneficial effects in reducing the morbidity associated with dialysis, but a small amount of acetate in bicarbonate dialysate may evoke hypotension or malaise. Acetate-free citrate hemodialysis (AFHD) may avoid these problems. In 44 hemodialysis patients bicarbonate hemodialysis (BHD) was conducted for three months, followed by a switch to AFHD for three months, and a further switch to bicarbonate hemodialysis (ReBHD). In BHD, AFHD and ReBHD, intra-dialysis hypotension and post-dialysis malaise were determined (hypotension: intra-dialysis systolic blood pressure (SBP) was expressed as a percentage of SBP at the start of hemodialysis, malaise was assessed by a self-reported 0 to 3 scale, 0: absence of malaise, 3: unbearable malaise). Compared with BHD, AFHD patients complained of less malaise but the intra-dialysis blood pressure change did not differ significantly (malaise: BHD 0.73 ± 0.76 vs. AFHD 0.32 ± 0.47, P < 0.0001, end hemodialysis SBP: BHD 93.6 ± 8.9 vs. AFHD 93.8 ± 10.1, P = NS). After switching to ReBHD from AFHD, the malaise score increased (AFHD 0.32 ± 0.47 vs. ReBHD 0.77 ± 0.89, P < 0.0001) and the intra-dialysis blood pressure dropped markedly (end hemodialysis SBP: AFHD 93.8 ± 10.1 vs. ReBHD 87.3 ± 10.5, P < 0.0001). Malaise was very severe in five patients who could not continue ReBHD. After ten days under ReBHD, ReBHD was changed to AFHD again in all patients. Although the exact mechanisms are not known, AFHD may be preferable to BHD to prevent hemodialysis-induced hypotension and malaise.
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Increased efficiency of hemodialysis with citrate dialysate: a prospective controlled study.
Kossmann, RJ, Gonzales, A, Callan, R, Ahmad, S
Clinical journal of the American Society of Nephrology : CJASN. 2009;(9):1459-64
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Abstract
BACKGROUND AND OBJECTIVES A bicarbonate dialysate acidified with citrate (CD) has been reported to have local anticoagulant effect. This study examines the effect of CD on dialysis efficiency, measured as eKt/Vurea, and predialysis concentrations of BUN, creatinine, phosphate, and beta-2 microglobulin in chronic dialysis units. DESIGN, SETTINGS, PARTICIPANTS, & MEASUREMENTS Three outpatient chronic hemodialysis units with 142 patients were switched to CD for 6 mo. Using each patient's prior 6 mo on regular bicarbonate dialysate acidified by acetate (AD) as control, eKt/Vurea was compared with that of CD. Follow-up data for 7 mo after the study were collected from about one-half of the participants remaining on CD and the others returned to AD. RESULTS eKt/Vurea, increased (P < 0.0001) from pre-CD value of 1.51 +/- 0.01 to 1.57 +/- 0.01 with CD. During CD use beta-2 microglobulin levels declined (P = 0.0001) from 28.1 +/- 10.0 to 25.9 +/- 10.0. Similarly, the concentrations of BUN, creatinine, and phosphate also decreased on CD (P < 0.008). In the poststudy period, eKt/Vurea for the patients staying on CD remained unchanged at 1.60 +/- 0.17 versus 1.59 +/- 0.18 (P = NS), whereas in those returning to AD the eKt/Vurea decreased from 1.55 +/- 0.20 to 1.52 +/- 0.17 (P < 0.0001). CONCLUSIONS Data suggest that CD use is associated with increased solute removal.
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Extracellular bicarbonate and non-bicarbonate buffering against lactic acid during and after exercise.
Böning, D, Klarholz, C, Himmelsbach, B, Hütler, M, Maassen, N
European journal of applied physiology. 2007;(4):457-67
Abstract
Defense of extracellular pH constancy against lactic acidosis can be estimated from changes (Delta) in lactic acid ([La]), [HCO(3)(-)], pH and PCO(2) in blood plasma because it is equilibrated with the interstitial fluid. These quantities were measured in earlobe blood during and after incremental bicycle exercise in 13 untrained (UT) and 21 endurance-trained (TR) males to find out if acute and chronic exercise influence the defense. During exercise the capacity of non-bicarbonate buffers (beta(nbi) = -Delta[La] . DeltapH(-1) - Delta[HCO(3)(-)] . DeltapH(-1)) available for the extracellular fluid (mainly hemoglobin, dissolved proteins and phosphates) amounted to 32 +/- 2(SEM) and 20 +/- 2 mmol l(-1) in UT and TR, respectively (P < 0.02). During recovery beta(nbi) decreased to 14 (UT) and 12(TR) mmol l(-1) (both P < 0.001) corresponding to values previously found at rest by in vivo CO(2) titration. Bicarbonate buffering (beta(bi)) amounted to 44-48 mmol l(-1) during and after exercise. The large exercise beta(nbi) seems to be mainly caused by an increasing concentration of all buffers due to shrinking of the extracellular volume, exchange of small amounts of HCO(3)(-) or H(+) with cells and delayed HCO(3)(-) equilibration between plasma and interstitial fluid. Increase of [HCO(3)(-)] during titration by these mechanisms augments total beta and thus the calculated beta(nbi) more than beta(bi) because it reduces DeltapH and Delta[HCO(3)(-)] at constant Delta[La]. The smaller rise in exercise beta(nbi) in TR than UT may be caused by an increased extracellular volume and an improved exchange of La(-), HCO(3)(-) and H(+) between trained muscles and blood.
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Gastric acid and salivary bicarbonate. Is there a relationship in duodenal ulcer patients?
Namiot, Z, Stasiewicz, J, Markowski, AR, Namiot, DB, Jaroszewicz, W, Kemona, A, Górski, J
Roczniki Akademii Medycznej w Bialymstoku (1995). 2004;:75-9
Abstract
PURPOSE Since saliva protects the oesophageal and oral mucosa against hydrogen ions, the aim of the study was to establish the relationship between the secretion of gastric acid and salivary bicarbonate. MATERIAL AND METHODS The study involved 43 Helicobacter pylori positive duodenal ulcer patients receiving: 1. omeprazole alone (O), 2. omeprazole and amoxicillin (OA) or 3. omeprazole, amoxicillin and tinidazole (OAT). In each study group the examination was performed twice, before and at the end of a two-week treatment, both under basal conditions and during a gastric secretory test with pentagastrin. Concentrations of gastric hydrogen ions and salivary bicarbonate were evaluated by the titration method. RESULTS In all therapeutic groups analysed separately, the secretion of gastric acid as well as salivary bicarbonate decreased at the end of the treatment, however only in OA and OAT groups the differences in bicarbonate reached statistical significance. As the changes in the concentration and output of both salivary bicarbonate and gastric acid had the same direction, the three therapeutic groups (O, OA, OAT) were subjected to combined analysis. It showed that under basal conditions and during stimulation with a gastric catheter or catheter and pentagastrin, bicarbonate concentration and output were higher before than at the end of the treatment. However, no direct correlation between gastric acid secretion and salivary bicarbonate was found in groups subjected to either separate or combined analysis. CONCLUSIONS The results of our study provide evidence for the partial involvement of hydrogen ions of gastric origin in the regulation of salivary bicarbonate secretion in duodenal ulcer patients.
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Growth and metabolic consequences of bladder augmentation in children with myelomeningocele and bladder exstrophy.
Mingin, GC, Nguyen, HT, Mathias, RS, Shepherd, JA, Glidden, D, Baskin, LS
Pediatrics. 2002;(6):1193-8
Abstract
OBJECTIVE Bladder augmentation using intestinal segments is reported to cause decreased linear growth in bladder exstrophy and myelomeningocele patients. We studied changes in calcium metabolism, height, bone chemistry, and bone density in exstrophy and myelomeningocele patients after bladder augmentation. METHODS Thirty-three patients were prospectively admitted to the Pediatric Clinical Research Center at the University of California San Francisco for 24 hours. Blood and urine were analyzed for electrolytes, and serum was obtained for markers of calcium metabolism. Dual radiograph bone densitometry of the forearm was performed. Myelomeningocele patients were compared with nonaugmented myelomeningocele patients matched by age, gender, level of defect, and ambulatory status. Exstrophy augmented patients were compared with nonaugmented exstrophy patients. The bone densities in both groups were compared with normal children. Laboratory values and percentile heights were statistically analyzed using the Student t test; bone densitometry was analyzed using the Tukey test. RESULTS Twenty-two patients with myelomeningocele and 11 with bladder exstrophy were studied. Mean follow-up was 3.7 years postaugmentation (range: 1-13 years). The results indicate a significant difference in serum bicarbonate and chloride levels between myelomeningocele patients who underwent ileal augmentation and those who did not. Although this may be indicative of chronic metabolic acidosis, there was no affect on growth or bone density when compared with controls. There were no other significant differences in laboratory values, or percentile heights, nor were any differences noted in patients who underwent gastrocystoplasty. In the exstrophy group, there were no observable differences in percentile height or laboratory values between the augmented and nonaugmented group. There were no significant differences in bone density between these 2 groups when matched for age and gender. No significant difference was seen in bone density when these groups were compared with normal children. CONCLUSION Bladder augmentation is safe and does not impact negatively on the linear growth or bone densities of patients with myelomeningocele or bladder exstrophy.
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Abnormal erythrocyte anion exchange in Alzheimer disease.
Greco, FA, Satlin, A, Solomon, AK
Archives of pathology & laboratory medicine. 2000;(8):1141-6
Abstract
CONTEXT Several abnormalities have been described in red blood cells of patients with Alzheimer disease (AD), but to date none of these has been confirmed by a second, independent study. Erythrocyte anion exchange has been reported to be abnormal in AD; we have developed a new technique for measuring anion exchange. OBJECTIVES To confirm the abnormality of erythrocyte anion exchange in AD and to determine whether the phenomenon has potential for clinical utility. DESIGN Comparison of patients with probable AD to age-matched controls. SETTING University hospital and ambulatory clinic. METHODS Chloride-bicarbonate exchange was measured in erythrocyte ghosts resealed with a fluorescent probe of chloride concentration. RESULTS Erythrocyte anion exchange is abnormal in AD. This difference appears in citrate but not EDTA anticoagulant. Mahalanobis's generalized distance between the 2 populations is 1.7, and a discriminant function derived from our technique classifies 82% of the study population in accordance with the National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria. Receiver operating characteristic analysis demonstrates the possibility of choosing cutoffs with high sensitivity and specificity. CONCLUSIONS Measurement of red blood cell anion exchange may be useful in classifying patients with AD. The dependence of this phenomenon on anticoagulant suggests the involvement of platelet activation or complement fixation.