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PubMed1993

Effects of spike discharge history on discharge probability and latency in frog basilar papilla units.

Gaumond et al. [(1982) J. Neurophysiol. 48, 856-873] showed in the cat that a multiplicative-intensity model can generally account quite well for reduction of the probability of an auditory-nerve spike by another spike preceding it by 4 to 25 ms, and that for smaller separations there is also an increased latency of the following spike. Bosch [(1990) D. Sc. Dissertation, Washington University, St. Louis, MO] made important improvements in experimental design and estimation techniques for studying these effects, and confirmed their presence in the gerbil. However, direct application of these methods to the frog does not yield reliable estimates. A clearer separation of discharge probability and latency effects in frog basilar papilla units is provided by the paired-click paradigm used in this study, which is applicable to low-spontaneous-rate units that generally respond to click stimuli with zero or one spike within a short interval following the click. The results confirm the existence in the frog of both spike-probability and spike-latency effects that are qualitatively similar to those found in mammals, although the absolute refractory time is much longer in frog, and the relative refractory time usually shorter. The paired-click paradigm also reveals a stimulus-history effect at stimulus levels which are near threshold: when there is no response to the first click, responses to the second click occur with increased probability and reduced latency.

Acoustic Stimulation↗

PubMed1995

Reduced N-acetylaspartate content in the frontal part of the brain in patients with probable Alzheimer's disease.

The fully relaxed water signal was used as an internal standard in a STEAM experiment to calculate the concentrations of the metabolites: N-acetylaspartate (NAA), creatine + phosphocreatine [Cr + PCr], and choline-containing metabolites (Cho) in the frontal part of the brain in 12 patients with probable Alzheimer's disease. Eight age-matched healthy volunteers served as controls. Furthermore, T1 and T2 relaxation times of the metabolites and signal ratios: NAA/Cho, NAA/[Cr + PCr], and [Cr + PCr]/Cho at four different echo times (TE) and two different repetition times (TR) were calculated. The experiments were carried out using a Siemens Helicon SP 63/84 wholebody MR-scanner at 1.5 T. The concentration of NAA was significantly lower in the patients with probable Alzheimer's disease than in the healthy volunteers. No significant difference was found for any other metabolite concentration. For the signal ratios the only statistically significant difference was that the NAA/Cho ratio at TE = 92 ms and TR = 1.6 s was lower in the patients with probable Alzheimer's disease compared with the control group. A trend towards a longer T2 relaxation time for NAA in the patients with probable Alzheimer's disease than among the healthy volunteers was found, but no significant difference was found concerning the T1 and T2 relaxation times.

Aged↗

PubMed1995

Comparison of defibrillation probability of success curves for an endocardial lead configuration with and without an inactive epicardial patch.

OBJECTIVES: This study sought to assess the effect of passive "bystander" epicardial electrodes on defibrillation efficacy. BACKGROUND: We hypothesized that an inactive epicardial patch placed in an area of low potential gradient from an endocardial electrode shock might affect defibrillation efficacy through its effects on the shock field and the underlying potential gradient. METHODS: We studied the effects of an inactive 18-cm2 titanium mesh patch placed on the anterolateral left ventricular epicardium on the 50% probability of successful defibrillation. A biphasic shock with both phases 6 ms in duration was delivered between superior vena cava and right ventricular catheter electrodes 10 s after the electrical induction of ventricular fibrillation. Six dogs underwent an up/down defibrillation protocol randomized with or without the patch on the heart. RESULTS: Mean 50% (+/-) probability point for energy doubled with the conductive patch on the heart, from 8.0 +/- 3.2 to 16.8 +/- 7.0 J (p < 0.01), and leading-edge voltage increased from 334 +/- 64 to 477 +/- 98 V (p < 0.01). Mean 50% probability points for energy and leading-edge voltage were not significantly changed when the procedure was repeated using a nonconductive patch in another six dogs as a control group. In a saline-saturated foam model, measurements from electrodes placed around and under the patch revealed a 72% mean decrease in the potential gradient in the foam under the conductive patch. CONCLUSIONS: A passive defibrillator patch can markedly increase the energy requirements for defibrillation, probably by decreasing the potential gradient under the patch. These results suggest the use of caution when passive electrodes are present, for example, when a patient receives a nonthoracotomy defibrillator system while epicardial electrodes from a previously implanted system are left in place.

Animals↗

PubMed2004

Estimating the probability and level of contamination with Salmonella of feed for finishing pigs produced in Switzerland--the impact of the production pathway.

Contaminated feed is a source of infection with Salmonella for livestock, including pigs. Because pigs rarely show clinical signs of salmonellosis, undetected carriers can enter the food production chain. In a "Farm to Fork" food safety concept, safe feed is the first step for ensuring safe food. Heat treatment or adding organic acids are process steps for reducing or eliminating a contamination with Salmonella. The aims of this study were (I) to estimate the probability and the level of Salmonella contamination in batches of feed for finishing pigs in Swiss mills and (II) to assess the efficacy of specific process steps for reducing the level of contamination with Salmonella. A quantitative release assessment was performed by gathering and combining data on the various parameters having an influence on the final contamination of feed. Fixed values and probability distributions attributed to these parameters were used as input values for a Monte Carlo simulation. The simulation showed that-depending on the production pathway-the probability that a batch of feed for finishing pigs contains Salmonella ranged from 34% (for feed on which no specific decontaminating step was applied) to 0% (for feed in which organic acids were added and a heat treatment was implemented). If contamination occurred, the level of contamination ranged from a few Salmonella kg(-1) feed to a maximum of 8E+04 Salmonella kg(-1) feed. Probability and levels of contamination were highest when no production process able to reduce or eliminate the pathogen was implemented. However, most of the Swiss production was shown to undergo some kind of decontaminating step. A heat treatment, in combination with the use of organic acids, was found as a solution of choice for the control of Salmonella in feed.

Animal Feed↗

PubMed2006

Prediction of radiation-induced liver disease by Lyman normal-tissue complication probability model in three-dimensional conformal radiation therapy for primary liver carcinoma.

PURPOSE: To describe the probability of RILD by application of the Lyman-Kutcher-Burman normal-tissue complication (NTCP) model for primary liver carcinoma (PLC) treated with hypofractionated three-dimensional conformal radiotherapy (3D-CRT). METHODS AND MATERIALS: A total of 109 PLC patients treated by 3D-CRT were followed for RILD. Of these patients, 93 were in liver cirrhosis of Child-Pugh Grade A, and 16 were in Child-Pugh Grade B. The Michigan NTCP model was used to predict the probability of RILD, and then the modified Lyman NTCP model was generated for Child-Pugh A and Child-Pugh B patients by maximum-likelihood analysis. RESULTS: Of all patients, 17 developed RILD in which 8 were of Child-Pugh Grade A, and 9 were of Child-Pugh Grade B. The prediction of RILD by the Michigan model was underestimated for PLC patients. The modified n, m, TD50 (1) were 1.1, 0.28, and 40.5 Gy and 0.7, 0.43, and 23 Gy for patients with Child-Pugh A and B, respectively, which yielded better estimations of RILD probability. The hepatic tolerable doses (TD5) would be MDTNL of 21 Gy and 6 Gy, respectively, for Child-Pugh A and B patients. CONCLUSIONS: The Michigan model was probably not fit to predict RILD in PLC patients. A modified Lyman NTCP model for RILD was recommended.

Adult↗

PubMed2004

Improving profile HMM discrimination by adapting transition probabilities.

Profile hidden Markov models (HMMs) are used to model protein families and for detecting evolutionary relationships between proteins. Such a profile HMM is typically constructed from a multiple alignment of a set of related sequences. Transition probability parameters in an HMM are used to model insertions and deletions in the alignment. We show here that taking into account unrelated sequences when estimating the transition probability parameters helps to construct more discriminative models for the global/local alignment mode. After normal HMM training, a simple heuristic is employed that adjusts the transition probabilities between match and delete states according to observed transitions in the training set relative to the unrelated (noise) set. The method is called adaptive transition probabilities (ATP) and is based on the HMMER package implementation. It was benchmarked in two remote homology tests based on the Pfam and the SCOP classifications. Compared to the HMMER default procedure, the rate of misclassification was reduced significantly in both tests and across all levels of error rate.

Algorithms↗

PubMed2004

Probability and determinants of relapse after discontinuation of inhaled corticosteroids in patients with COPD treated in general practice.

OBJECTIVE: The objective of the study was to assess the probability, and explore determinants of adverse respiratory outcome after discontinuation of inhaled corticosteroid (ICS) treatment in subjects with chronic obstructive pulmonary disease (COPD) diagnosed and treated in general practice. DESIGN: Prospective unblinded ICS withdrawal study. SUBJECTS: 201 ICS treated COPD patients with various degrees of airflow limitation from 45 Dutch general practices. MAIN OUTCOME MEASURES: Probability of and time to exacerbation or unremitting worsening of respiratory symptoms after ICS discontinuation. RESULTS: Mean age was 60.6 (S.D. 9.5) years, post-bronchodilator forced expiratory volume in 1s (FEV1) 65.6 (S.D. 15.7) % predicted. Overall probability of adverse respiratory outcome after ICS discontinuation was 0.37 (95% confidence interval (CI) 0.31, 0.44). Survival analysis showed that age, gender, smoking status and reversibility of airflow limitation were independent predictors of adverse respiratory outcome. For females, the adjusted hazard ratio was 2.14 (95% CI 1.31, 3.50) compared to males. For age, the hazard ratio was 1.05 (95% CI 1.02, 1.08) per year lived. CONCLUSION: Discontinuation of inhaled corticosteroids may harm patients with COPD. The probability of an adverse respiratory outcome may be higher in women, elderly patients, smokers and patients with higher bronchodilator reversibility while on inhaled steroid treatment.

Journal Article↗

PubMed2005

Estimating the probability of freedom of classical swine fever virus of the East-Belgium wild-boar population.

A report of the Scientific Committee on Animal Health and Animal Welfare of the European Commission (CEC, 1999.) includes recommendations for setting up monitoring programmes for classical swine fever (CSF) infection in a wild-boar population, based on the assumption that one would detect at least 5% prevalence in a CSF-infected wild-boar population. This assumption, however, is not science based. We propose an alternative method to provide evidence for a wild-boar population being free of CSF and evaluate the efficiency of a surveillance programme that was implemented in Belgium in 1998. In our study, the probability of freedom of CSF-virus was estimated based on 789 samples; these were collected from wild-boars within the surveillance programme (within the three provinces which include 95% of the Belgian wild-boar population) and examined by three diagnostics methods (antibody detection, virus detection and virus RNA detection). A Bayesian framework was used for the estimation, accounting for the diagnostic test characteristics without the assumption of the presence of a gold standard. The median probability of freedom of CSF-virus was estimated at 0.970, with a 95% credibility interval of 0.149-1.000. Independent on the choice of the prior information, the posterior distributions for the probability of freedom of CSF-virus were always skewed close to the upper boundary of 1. This represents a big gain of knowledge since we did not use any prior information for the probability of freedom of CSF-virus and took the uncertainty about the accuracy of the diagnostic methods into account.

Animals↗

PubMed2005

Effect of repeated administration of PGF2alpha in the early post partum period on the prevalence of clinical endometritis and probability of pregnancy at first insemination in lactating dairy cows.

Two experiments were performed to determine the effects of repeated administration of PGF2alpha in the immediate post partum period on the prevalence of clinical endometritis at 22 and 58 days post partum, and the probability of pregnancy at first insemination, in post partum dairy cows. In Experiment 1, 228 cows on day 7 post partum were used. Cows in Group 1 (n = 114) were treated twice with PGF2alpha (25 mg, im) 8 h apart on days 7 and 14 post partum, and only once on days 22 and 35 post partum. Cows in Group 2 (n = 114) served as untreated controls. Vaginoscopy and transrectal palpation of the genital tract were done on days 22 and 58 post partum. Cows in both groups were inseminated at estrus after a voluntary waiting period of 100 days. Pregnancy was determined by transrectal palpation between 45 and 50 days after insemination. Repeated administration of PGF2alpha in the immediate post partum period did not reduce the prevalence of clinical endometritis on days 22 or 58 post partum (65 versus 62% on day 22 and 28.3 versus 35.2% on day 58 in Groups 1 and 2, respectively). There was no significant difference in the probability of pregnancy at first insemination between cows in both groups. In Experiment 2, 418 cows on day 7 post partum were used. Cows in Group 1 (n = 209) were treated twice with PGF2alpha (25 mg, im) 8h apart on days 7 and 14 post partum, and only once on days 22 and 35 post partum. Cows in Group 2 (n = 209) served as untreated controls. Cows in both groups were subjected to the Presynch and Ovsynch protocols on days 49 and 75 post partum, respectively. Pregnancy was determined by transrectal ultrasonography between days 29 and 32 after timed insemination. There was no significant difference in the probability of pregnancy at first insemination between cows in both groups. In conclusion, repeated administration of PGF2alpha to cows in this herd had no effect on the prevalence of clinical endometritis at 22 and 58 days post partum, and that there was no effect on the probability of pregnancy after insemination at estrus among cows with a voluntary waiting period of > 100 days, or at timed AI at 85 days in milk when Presynch was employed.

Animals↗

PubMed2004

Effects on orientation perception of manipulating the spatio-temporal prior probability of stimuli.

Spatial and temporal regularities commonly exist in natural visual scenes. The knowledge of the probability structure of these regularities is likely to be informative for an efficient visual system. Here we explored how manipulating the spatio-temporal prior probability of stimuli affects human orientation perception. Stimulus sequences comprised four collinear bars (predictors) which appeared successively towards the foveal region, followed by a target bar with the same or different orientation. Subjects' orientation perception of the foveal target was biased towards the orientation of the predictors when presented in a highly ordered and predictable sequence. The discrimination thresholds were significantly elevated in proportion to increasing prior probabilities of the predictors. Breaking this sequence, by randomising presentation order or presentation duration, decreased the thresholds. These psychophysical observations are consistent with a Bayesian model, suggesting that a predictable spatio-temporal stimulus structure and an increased probability of collinear trials are associated with the increasing prior expectation of collinear events. Our results suggest that statistical spatio-temporal stimulus regularities are effectively integrated by human visual cortex over a range of spatial and temporal positions, thereby systematically affecting perception.

Bayes Theorem↗

PubMed2000

Evaluation of chest pain in patients with low to intermediate pretest probability of coronary artery disease by electron beam computed tomography.

Despite its limited sensitivity and specificity in patients with low to intermediate probability of coronary artery disease (CAD), exercise treadmill testing (ETT) is frequently used as the initial test for investigation of chest pain. Although myocardial perfusion imaging is a significantly more accurate test, its added cost to ETT is considerable. The cost of a non-contrast electron beam computed tomography (EBCT) scan is comparable to that of ETT and the calcium score (CS) correlates closely with the volume of atherosclerotic plaque. Therefore, we tested the hypothesis that EBCT might be an effective and cost-beneficial technique for the identification of angiographically obstructive CAD (> or = 50% stenosis) in patients with low to intermediate pretest probability of disease. We calculated the theoretic cost of attaining a diagnosis of CAD based on a Bayesian model that utilizes published sensitivity and specificity levels for ETT, EBCT, and stress myocardial perfusion imaging. We then submitted a cohort of 207 patients with low to intermediate probability of disease both to EBCT and ETT in random order, and estimated the cost of achieving a correct diagnosis by either route based on the number of expected further tests. An EBCT calcium score of 150 was chosen as a cut-point with a sensitivity of 74% and a specificity of 89% for the presence of obstructive CAD. The theoretic Bayesian model predicted substantial cost savings when EBCT was used as the initial test instead of ETT, with decreasing benefit as the prevalence of disease increased (44% saving at 0% prevalence; 15% saving at 100% prevalence). In the patient cohort, the diagnostic pathway starting with EBCT provided a 45% to 65% cost saving over the ETT pathway. We conclude that in patients with low to intermediate pretest probability of disease, a pathway based on EBCT as the initial test to investigate presence of obstructive CAD provides a substantial cost benefit over a pathway based on ETT. Such cost advantages decrease as the prevalence of disease increases.

Adult↗

PubMed2001

Exercise echocardiography for the prognostic stratification of patients with low pretest probability of coronary artery disease.

PURPOSE: The aim of this study was to determine whether exercise echocardiography provides incremental data for risk stratification of patients with a low pretest probability of coronary artery disease. PATIENTS AND METHODS: The study included patients referred for exercise echocardiography whose probability of coronary artery disease was 25% or less. We calculated an exercise wall motion score index (on a 1-5 scale), an indicator of the extent and severity of exercise-induced abnormalities. The primary outcomes of the study were subsequent cardiac events (cardiac death and nonfatal myocardial infarction). RESULTS: We studied 571 men and 1047 women; their mean (+/- SD) age was 55 +/- 13 years. During a median follow-up of 3 years, there were 19 cardiac events (6 cardiac deaths and 13 nonfatal myocardial infarctions); an additional 37 patients underwent coronary revascularization. In a multivariate analysis of clinical, exercise electrocardiographic, and echocardiographic parameters, exercise wall motion score index (hazard ratio [HR] = 2.1 per 0.5 units; 95% confidence interval [CI]: 1.3 to 3.4), and age (HR = 2.0 per decade; 95% CI: 1.2-2.8) were independently associated with the risk of cardiac events. Although exercise echocardiographic variables contributed significantly (P = 0.01) to a model of the risk of adverse events, only 9 (47%) of the 19 patients with cardiac events were identified by an abnormal exercise echocardiogram. CONCLUSION: Among patients with low pretest probability of coronary artery disease by clinical criteria, exercise echocardiography identifies some, but not all, patients at risk of future events. Because of the low event rate, routine application of exercise echocardiography in a patient with a low pretest probability does not appear to be cost-effective and therefore cannot be recommended.

Adult↗

PubMed1998

Severity of pelvic inflammatory disease as a predictor of the probability of live birth.

OBJECTIVE: Our aim was to study the association between severity of pelvic inflammatory disease at laparoscopy and the probability of achieving a live birth, while accounting for subsequent episodes of pelvic inflammatory disease. STUDY DESIGN: Beginning in 1960 a cohort of 1288 women in Lund, Sweden, who had clinical symptoms of acute pelvic inflammatory disease and who desired pregnancy was followed for up to 24 years. All participants underwent laparoscopy and were categorized by degree of salpingitis: mild (n = 371), moderate (n = 580), or severe (n = 337) pelvic inflammatory disease. Cumulative live birth rates, obtained by life-table analysis, and proportional hazards ratios were compared among women by severity of pelvic inflammatory disease, while accounting for subsequent episodes. RESULTS: The cumulative proportion of women achieving a live birth after 12 years was 90% for women with mild, 82% for women with moderate, and 57% for women with severe pelvic inflammatory disease. The occurrence of subsequent episodes in women with mild pelvic inflammatory disease did not diminish their long-term probability of live birth, whereas it significantly lowered the probability of live birth in women with severe pelvic inflammatory disease. Women with severe disease and subsequent episodes were eight times more likely to fail to achieve live birth compared with women with a single pelvic inflammatory disease episode with mild disease (relative risk 8.1; 95% confidence interval 3.0 to 22.2). CONCLUSIONS: Increasing severity of pelvic inflammatory disease correlates with a lower long-term probability of live birth. Subsequent episodes have a greater impact on women with severe pelvic inflammatory disease at the index episode compared with those with milder disease.

Adult↗

PubMed2000

The probability of quantal secretion near a single calcium channel of an active zone.

A Monte Carlo analysis has been made of calcium dynamics and quantal secretion at microdomains in which the calcium reaches very high concentrations over distances of <50 nm from a channel and for which calcium dynamics are dominated by diffusion. The kinetics of calcium ions in microdomains due to either the spontaneous or evoked opening of a calcium channel, both of which are stochastic events, are described in the presence of endogenous fixed and mobile buffers. Fluctuations in the number of calcium ions within 50 nm of a channel are considerable, with the standard deviation about half the mean. Within 10 nm of a channel these numbers of ions can give rise to calcium concentrations of the order of 100 microM. The temporal changes in free calcium and calcium bound to different affinity indicators in the volume of an entire varicosity or bouton following the opening of a single channel are also determined. A Monte Carlo analysis is also presented of how the dynamics of calcium ions at active zones, after the arrival of an action potential and the stochastic opening of a calcium channel, determine the probability of exocytosis from docked vesicles near the channel. The synaptic vesicles in active zones are found docked in a complex with their calcium-sensor associated proteins and a voltage-sensitive calcium channel, forming a secretory unit. The probability of quantal secretion from an isolated secretory unit has been determined for different distances of an open calcium channel from the calcium sensor within an individual unit: a threefold decrease in the probability of secretion of a quantum occurs with a doubling of the distance from 25 to 50 nm. The Monte Carlo analysis also shows that the probability of secretion of a quantum is most sensitive to the size of the single-channel current compared with its sensitivity to either the binding rates of the sites on the calcium-sensor protein or to the number of these sites that must bind a calcium ion to trigger exocytosis of a vesicle.

Action Potentials↗

PubMed2003

Heterogeneous presynaptic release probabilities: functional relevance for short-term plasticity.

We discuss a model of presynaptic vesicle dynamics, which allows for heterogeneity in release probability among vesicles. Specifically, we explore the possibility that synaptic activity is carried by two types of vesicles; first, a readily releasable pool and, second, a reluctantly releasable pool. The pools differ regarding their probability of release and time scales on which released vesicles are replaced by new ones. Vesicles of both pools increase their release probability during repetitive stimulation according to the buildup of Ca(2+) concentration in the terminal. These properties are modeled to fit data from the calyx of Held, a giant synapse in the auditory pathway. We demonstrate that this arrangement of two pools of releasable vesicles can account for a variety of experimentally observed patterns of synaptic depression and facilitation at this synapse. We conclude that synaptic transmission cannot be accurately described unless heterogeneity of synaptic release probability is taken into account.

Action Potentials↗

PubMed2003

Increased open probability of single cardiac L-type calcium channels in patients with chronic atrial fibrillation. role of phosphatase 2A.

BACKGROUND: The L-type calcium channel (LCC) plays a crucial role in the electrical remodeling of atrial fibrillation (AF). AF is associated with reduction of L-type calcium current density, due to a transcriptional downregulation of the pore forming alpha(1c)-subunit of LCC. However, it is unclear, whether this current reduction is related to a decrease in channel number or to alterations in channel function. Hence, we performed a single LCC analysis to assess channel gating and function in human AF. METHODS AND RESULTS: We used the cell-attached patch-clamp technique in isolated atrial human cardiomyocytes of 25 patients with sinus rhythm (SR) and 15 patients with chronic AF. Protein expression of the pore-forming alpha(1c)-subunit of LCC was reduced by 40% in AF. Single channel peak average current was 1.7-fold higher in AF than in SR, due to a 3.1-fold higher open probability of LCC. Since phosphatase 2A (PP2A) is known to preferentially reduce LCC open probability via channel dephosphorylation, we assessed whether PP2A expression or activity is reduced in AF. Okadaic acid, an inhibitor of phosphatases, increased channel open probability in SR, but not in AF. However, Western blot analysis of atrial homogenates of the same patient population revealed unchanged expression of PP2A. CONCLUSIONS: Human AF is characterized by increased single LCC activity, due to an increase of channel open probability. The blunted effect of PP2A on LCC as shown by single channel analysis may be related to a reduction of cytosolic PP2A activity or impaired local interaction between PP2A and LCC in AF.

Adrenergic beta-Agonists↗

PubMed2000

Probability density estimation using incomplete data

An unsupervised method of learning probability density function parameters in the framework of mixture densities from incomplete data is developed. Unsupervised learning can be considered as learning from observations as they are received. In real-world processes, there are many imperfections in the observations. The Expectation-Maximization algorithm is used to iteratively find the maximum likelihood estimate of the missing values and the parameters of the probability density function. Reliability of the Expectation-Maximization algorithm and its convergence properties during the learning process from incomplete data are presented. Three examples of learning mixture probability density function parameters from an incomplete data set are presented and the boundaries of properly estimating the mixture probability density function parameters as the percentage of missing data increases are examined.

Journal Article↗

PubMed1983

Effect of calcium restriction on renal excretion of oxalate and the probability of stones in the various pathophysiological groups with calcium stones.

To evaluate the adequacy of simple calcium restriction for patients with idiopathic calcium stones the effect of 5 days of calcium restriction without oxalate restriction on renal excretion of calcium and oxalate, and the corresponding probability of stones were assessed in 50 controls and 48 patients. Renal excretion of calcium decreased and that of oxalate increased significantly in all groups but the importance of the changes was critically dependent upon the underlying pathophysiological condition. The probability of stones decreased only in patients with absorptive hypercalciuria type II owing to the usual excessive calcium intake and increased in those with absorptive hypercalciuria type I and renal hypercalciuria, which are associated with true hyperabsorption of calcium and represent the 2 forms of idiopathic hypercalciuria. We believe that simple calcium restriction is beneficial for patients with idiopathic calculi only when the hypercalciuria is caused by exaggerated intake of calcium, since it increases the probability of stones in patients with idiopathic hypercalciuria. Calcium restriction always is associated with an increase in oxalate excretion, suggesting that simultaneous oxalate restriction should be added in all cases to decrease the probability of stones.

Adult↗