Acid production and base balance in patients on chronic haemodialysis

2001 ◽  
Vol 101 (4) ◽  
pp. 329-337 ◽  
Author(s):  
R. MIONI ◽  
M. GROPUZZO ◽  
M. MESSA ◽  
G. BOSCUTTI ◽  
A. D'ANGELO ◽  
...  
Keyword(s):  
Acid Production ◽  
Alternative Hypothesis ◽  
Tap Water ◽  
Whole Body ◽  
Chronic Haemodialysis ◽  
Normal Limits ◽  
Inorganic Cation ◽  
Before And After ◽  
Base Balance ◽  
Total Base

Acid generation and elimination processes were compared with total base (bicarbonate plus metabolizable anions) turnover in 18 anuric patients undergoing post-dilutional haemofiltration. The study was conducted during the second haemodialysis session of the week by means of a whole-body base balance technique. The results showed that the mean rates of base loss and base gain during dialysis did not differ (i.e. the dialysis base balance approximated to zero). The concurrent mean rate of intestinal base absorption was 66±26 mmol/2 days, as calculated from the whole-body balance of the various inorganic cation and anion differences in a metabolic steady state. This level of intestinal base absorption would be capable of neutralizing the 59±21 mmol of H+ ions/2 days that is contributed by sulphuric acid, which is the most important endogenous acid produced in anuric patients. In spite of the fact that intestinal base supply was adequate to neutralize endogenous acid production completely, our patients presented with pre-dialysis non-carbonic acidosis. The depression of plasma bicarbonate levels could not, however, be explained by increased concentrations of the anion gap and organic acids, which were within normal limits both before and after dialysis. We suggest as an alternative hypothesis that this pre-dialysis acidosis may represent an isotonic dilution acidosis that is induced by the ingestion of base-free tap water in order for plasma tonicity to be protected from the accumulation of impermeant dietary solutes, which takes place during the interdialysis period in anuric patients.

Whole body acid-base modeling revisited

2017 ◽  
Vol 312 (4) ◽  
pp. F647-F653 ◽  
Author(s):  
Troels Ring ◽  
Søren Nielsen
Keyword(s):  
Acid Production ◽  
Negative Charge ◽  
Whole Body ◽  
Acid Excretion ◽  
Acid Base Balance ◽  
Acid Base ◽  
Conventional Model ◽  
Renal Net Acid Excretion ◽  
Base Balance ◽  
Alkali Absorption

The textbook account of whole body acid-base balance in terms of endogenous acid production, renal net acid excretion, and gastrointestinal alkali absorption, which is the only comprehensive model around, has never been applied in clinical practice or been formally validated. To improve understanding of acid-base modeling, we managed to write up this conventional model as an expression solely on urine chemistry. Renal net acid excretion and endogenous acid production were already formulated in terms of urine chemistry, and we could from the literature also see gastrointestinal alkali absorption in terms of urine excretions. With a few assumptions it was possible to see that this expression of net acid balance was arithmetically identical to minus urine charge, whereby under the development of acidosis, urine was predicted to acquire a net negative charge. The literature already mentions unexplained negative urine charges so we scrutinized a series of seminal papers and confirmed empirically the theoretical prediction that observed urine charge did acquire negative charge as acidosis developed. Hence, we can conclude that the conventional model is problematic since it predicts what is physiologically impossible. Therefore, we need a new model for whole body acid-base balance, which does not have impossible implications. Furthermore, new experimental studies are needed to account for charge imbalance in urine under development of acidosis.

Acid production and base balance in patients on chronic haemodialysis

2001 ◽  
Vol 101 (4) ◽  
pp. 329
Author(s):  
R. MIONI ◽  
M. GROPUZZO ◽  
M. MESSA ◽  
G. BOSCUTTI ◽  
A. D’ANGELO ◽  
...  
Keyword(s):  
Acid Production ◽  
Chronic Haemodialysis ◽  
Base Balance

scholarly journals Response in Growth, Scute Development, and Whole-Body Ion Composition of Acipenser fulvescens Reared in Water of Differing Chemistries

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1419
Author(s):  
Janet Genz ◽  
Rachael Hicks
Keyword(s):  
River Water ◽  
Growth And Development ◽  
Lake Sturgeon ◽  
Whole Body ◽  
Acipenser Fulvescens ◽  
Water Type ◽  
Ion Composition ◽  
Ion Concentrations ◽  
Before And After ◽  
Yolk Absorption

In fishes, environmental ion availability can have substantial effects on growth and development. This study examined the development of Lake Sturgeon in response to the varying environmental ion availability that they experience as part of a conservation stocking program. We reared sturgeon in natural water from the Coosa River, which had higher concentrations of Mg2+, Na+, and Zn2+ than standard hatchery conditions, while [Ca2+] at the Warm Springs National Fish Hatchery was 2× higher than in the Coosa River. Eggs were hatched in each water type and the larvae were sampled at time points before and after yolk absorption during the first 8 weeks of development. Total length and weight in WSNFH larvae were significantly higher than larvae in Coosa River water starting at 8 dph, indicating that growth was dependent on the different environmental ion levels. Concentrations of the ions of interest were also determined for whole-body acid digests of the exposed Lake Sturgeon. We found that Lake Sturgeon reared in Coosa River water had significantly higher magnesium and zinc than Lake Sturgeon reared in WSNFH water (p < 0.05), while calcium was significantly higher in WSNFH than Coosa River water. This difference shows that different environmental ion concentrations also impact the overall development of larval Lake Sturgeon.

scholarly journals A method for evaluation of patient-specific lean body mass from limited-coverage CT images and its application in PERCIST: comparison with predictive equation

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Jingjie Shang ◽  
Zhiqiang Tan ◽  
Yong Cheng ◽  
Yongjin Tang ◽  
Bin Guo ◽  
...  
Keyword(s):  
Lean Body Mass ◽  
Body Mass ◽  
Whole Body ◽  
Patient Specific ◽  
Predictive Equation ◽  
Reference Standard ◽  
Pet Ct ◽  
Before And After ◽  
Percist 1.0 ◽  
Limited Coverage

Abstract Background Standardized uptake value (SUV) normalized by lean body mass ([LBM] SUL) is recommended as metric by PERCIST 1.0. The James predictive equation (PE) is a frequently used formula for LBM estimation, but may cause substantial error for an individual. The purpose of this study was to introduce a novel and reliable method for estimating LBM by limited-coverage (LC) CT images from PET/CT examinations and test its validity, then to analyse whether SUV normalised by LC-based LBM could change the PERCIST 1.0 response classifications, based on LBM estimated by the James PE. Methods First, 199 patients who received whole-body PET/CT examinations were retrospectively retrieved. A patient-specific LBM equation was developed based on the relationship between LC fat volumes (FVLC) and whole-body fat mass (FMWB). This equation was cross-validated with an independent sample of 97 patients who also received whole-body PET/CT examinations. Its results were compared with the measurement of LBM from whole-body CT (reference standard) and the results of the James PE. Then, 241 patients with solid tumours who underwent PET/CT examinations before and after treatment were retrospectively retrieved. The treatment responses were evaluated according to the PE-based and LC-based PERCIST 1.0. Concordance between them was assessed using Cohen’s κ coefficient and Wilcoxon’s signed-ranks test. The impact of differing LBM algorithms on PERCIST 1.0 classification was evaluated. Results The FVLC were significantly correlated with the FMWB (r=0.977). Furthermore, the results of LBM measurement evaluated with LC images were much closer to the reference standard than those obtained by the James PE. The PE-based and LC-based PERCIST 1.0 classifications were discordant in 27 patients (11.2%; κ = 0.823, P=0.837). These discordant patients’ percentage changes of peak SUL (SULpeak) were all in the interval above or below 10% from the threshold (±30%), accounting for 43.5% (27/62) of total patients in this region. The degree of variability is related to changes in LBM before and after treatment. Conclusions LBM algorithm-dependent variability in PERCIST 1.0 classification is a notable issue. SUV normalised by LC-based LBM could change PERCIST 1.0 response classifications based on LBM estimated by the James PE, especially for patients with a percentage variation of SULpeak close to the threshold.

Changes on recovery in the concentrations of tryptophan and the biogenic amine metabolites in the cerebrospinal fluid of patients with affective illness

1973 ◽  
Vol 3 (3) ◽  
pp. 319-325 ◽  
Author(s):  
G. W. Ashcroft ◽  
Ivy M. Blackburn ◽  
D. Eccleston ◽  
A. I. M. Glen ◽  
W. Hartley ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Homovanillic Acid ◽  
Affective Illness ◽  
Normal Limits ◽  
Low Concentrations ◽  
Depressed Group ◽  
Before And After ◽  
Acid Metabolites ◽  
Bipolar Patients ◽  
Manic Patients

SYNOPSISThe concentration of the acid metabolites of dopamine, and 5-hydroxytryptamine (5-HT), homovanillic acid (HVA), and 5-hydroxyindolacetic acid (5-HIAA) respectively, were estimated in the cerebrospinal fluid of patients suffering from either unipolar or bipolar affective illness, both before and after recovery. Significantly low concentrations of HVA and 5-HIAA (P<0·01 and 0·05 respectively) were found in the unipolar depressed group and these did not return to normal on recovery. Depressed bipolar patients had levels within normal limits. In bipolar manic patients the HVA concentration fell on recovery to a level significantly lower (P<0·05) than controls. There was no difference in the levels of tryptophan in the CSF of any of the groups of patients nor was there any alteration on recovery. There was a high correlation between 5-HIAA and HVA in the same CSF. These findings are against the amine hypothesis which postulated in depression a lowered concentration of transmitter amine at synaptic junction.

Acute cold stress in rheumatoid arthritis inadequately activates stress responses and induces an increase of interleukin 6

2008 ◽  
Vol 68 (4) ◽  
pp. 572-578 ◽  
Author(s):  
R H Straub ◽  
G Pongratz ◽  
H Hirvonen ◽  
T Pohjolainen ◽  
M Mikkelsson ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Stress Response ◽  
Cold Stress ◽  
Stress Responses ◽  
Plasma Levels ◽  
Acute Stress ◽  
Whole Body ◽  
Cold Therapy ◽  
Before And After ◽  
Sympathetic Stress

Objective:Acute stress in patients with rheumatoid arthritis (RA) should stimulate a strong stress response. After cryotherapy, we expected to observe an increase of hormones of the adrenal gland and the sympathetic nervous system.Methods:A total of 55 patients with RA were recruited for whole-body cryotherapy at −110°C and −60°C, and local cold therapy between −20°C and −30°C for 7 days. We measured plasma levels of steroid hormones, neuropeptide Y (sympathetic marker), and interleukin (IL)6 daily before and after cryotherapy.Results:In both therapy groups with/without glucocorticoids (GC), hormone and IL6 levels at baseline and 5 h after cold stress did not change over 7 days of cryotherapy. In patients without GC, plasma levels of cortisol and androstenedione were highest after −110°C cold stress followed by −60°C or local cold stress. The opposite was found in patients under GC therapy, in whom, unexpectedly, −110°C cold stress elicited the smallest responses. In patients without GC, adrenal cortisol production increased relative to other adrenal steroids, and again the opposite was seen under GC therapy with a loss of cortisol and an increase of dehydroepiandrosterone. Importantly, there was no sympathetic stress response in both groups. Patients without GC and −110°C cold stress demonstrated higher plasma IL6 compared to the other treatment groups (not observed under GC), but they showed the best clinical response.Conclusions:We detected an inadequate stress response in patients with GC. It is further shown that the sympathetic stress response was inadequate in patients with/without GC. Paradoxically, plasma levels of IL6 increased under strong cold stress in patients without GC. These findings confirm dysfunctional stress axes in RA.

Effects of adaptation of vestibulo-ocular reflex function on manual target localization

2000 ◽  
Vol 10 (2) ◽  
pp. 75-86 ◽  
Author(s):  
Jacob J. Bloomberg ◽  
Lauren A. Merkle ◽  
Susan R. Barry ◽  
William P. Huebner ◽  
Helen S. Cohen ◽  
...  
Keyword(s):  
Adaptive Modulation ◽  
Normal Subjects ◽  
Target Localization ◽  
Whole Body ◽  
Spatial Coding ◽  
Ocular Reflex ◽  
Manual Responses ◽  
Vestibular Cues ◽  
Before And After ◽  
Vestibulo Ocular Reflex

The goal of the present study was to determine if adaptive modulation of vestibulo-ocular reflex (VOR) function is associated with commensurate alterations in manual target localization. To measure the effects of adapted VOR on manual responses we developed the Vestibular-Contingent Pointing Test (VCP). In the VCP test, subjects pointed to a remembered target following passive whole body rotation in the dark. In the first experiment, subjects performed VCP before and after wearing 0.5X minifying lenses that adaptively attenuate horizontal VOR gain. Results showed that adaptive reduction in horizontal VOR gain was accompanied by a commensurate change in VCP performance. In the second experiment, bilaterally labyrinthine deficient (LD) subjects were tested to confirm that vestibular cues were central to the spatial coding of both eye and hand movements during VCP. LD subjects performed significantly worse than normal subjects. These results demonstrate that adaptive change in VOR can lead to alterations in manual target localization.

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