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M Leon

Publications and source records attributed to M Leon.

At least 37 records · Page 2Linked to original sources

Early olfactory enrichment and deprivation both decrease beta-adrenergic receptor density in the main olfactory bulb of the rat.

The density of noradrenergic locus coeruleus projections and beta-adrenergic receptors in the main olfactory bulb of the rat increases with age. Both beta 1- and beta 2-adrenergic receptor subtypes exhibit laminar distributions, with focal regions of high receptor density present within the neuropil of individual glomeruli. Since the first synaptic contacts between olfactory receptor neurons and bulbar neurons occur within the glomeruli, early olfactory experiences possibly could influence the density or distribution of beta-adrenergic receptors in the bulb. We therefore investigated the effects of olfactory deprivation and early olfactory enrichment on the density and distribution of beta-adrenergic receptors in the main olfactory bulb. Animals were subjected to either unilateral naris closure on postnatal day 1 or odor training from postnatal days 1-18. Bulbs were removed on postnatal day 19 and subjected to quantitative autoradiography using the beta-adrenergic receptor antagonist [125I]iodopindolol and specific receptor subtype antagonists ICI 118,551 (beta 2-antagonist) and ICI 89,406 (beta 1-antagonist). Unilateral naris occlusion decreased both the number of beta 2 glomerular foci and the density of beta 1 and beta 2 receptors in the deprived bulb compared to the nondeprived bulb. Early odor training resulted in a significant decrease in the number, area, and receptor density of beta 2 glomerular foci in the midlateral region of the bulb. The distribution of beta 2 glomerular foci also differs with these two sensory manipulations. Changes in beta-adrenergic receptor density in response to both early learning and olfactory deprivation may be induced by a transient increase in olfactory bulb norepinephrine.

Animals

Early odor preference training increases olfactory bulb norepinephrine.

In vivo microdialysis sampling of the olfactory bulbs of awake rats on PND 3 revealed that olfactory stimulation alone does not alter extracellular norepinephrine (NE) levels. Tactile stimulation that is designed to mimic maternal interactions with the young does increase bulb NE and the combined odor and tactile stimulation further increases NE levels. These data are consistent with a critical role for NE in the development of early olfactory preferences in infant rats, induced by odor/tactile stimulation pairings. PND 10 odor/tactile stimulation does not evoke an increase in NE, data consistent with the finding that odor preference training of this kind is ineffective after about the first week of life. Oral infusion of milk on PND 3 also increases bulb NE, a finding consistent with the role of milk as a reinforcing stimulus for the development of early olfactory preferences. Finally, infusion of potassium into the bulb on PND 3 produces a rapid increase in NE, indicating a local neuronal origin of the NE in response to stimulation.

Administration, Oral

Olfactory bulb glycogen metabolism: noradrenergic modulation in the young rat.

The olfactory bulb exhibits high glycogen phosphorylase activity, the rate-limiting enzyme in the mobilization of glycogen. The bulb also receives dense noradrenergic innervation and noradrenaline is known to stimulate glycogen breakdown. We determined the levels of glycogen in the bulb over the course of development and then determined the ability of noradrenaline to mobilize bulb glycogen. At birth, olfactory bulbs have very high levels of glycogen, with levels declining as the pups develop. Picomolar levels of noradrenaline mobilize glycogen in the bulb,. Initially, beta-adrenergic receptors mediate teh glycogenolysis and subsequently, the alpha-noradrenergic receptors in the bulb stimulate the breakdown of glycogen. Carnosine is involved in the repletion of bulb glycogen levels. The stimulation of glycogen breakdown by noradrenaline may play a role in allowing the increased activity that accompanies early olfactory stimulation.

Aging

Olfactory experience modulated apoptosis in the developing olfactory bulb.

Early sensory stimulation plays a key role in shaping the structure and function of the developing olfactory system. Here, we provide the first direct evidence for apoptotic cell death in the olfactory bulbs of rat pups during normal development and we also demonstrate that olfactory deprivation by unilateral naris occlusion causes a dramatic increase in apoptotic cell death in the glomerular and granule cell layers of the deprived bulb. The accessory olfactory bulbs displayed a remarkably high basal level of apoptosis but the occluded accessory bulb did not differ in that regard from the control accessory bulb. These results suggest that apoptosis may be an important mechanism by which the olfactory system can adjust its cell numbers in response in sensory stimuli experienced in early life, thereby underlying one form of plasticity in the developing olfactory system.

Animals

Distribution and development of beta-adrenergic receptors in the rat olfactory bulb.

Beta-adrenergic stimulation appears to be involved in the establishment of both learned olfactory preferences and functional changes in the olfactory bulb of young rats. We examined the postnatal development of beta-adrenergic receptors within the main olfactory bulb to determine the density and distribution of these receptors. To quantify beta-adrenergic receptor density, olfactory bulb homogenates from postnatal day (PND) 1, 6, 12, and 19 rats were assessed for receptor binding with 125I-iodopindolol. In addition, receptor autoradiography was performed with the selective beta 1 antagonist ICI 89,406 and selective beta 2 antagonist ICI 118,551 on tissue sections from PND 1-30 rats to examine the distribution of the beta-adrenergic receptor subtypes. We observed both an increase in receptor density with increasing age and the formation of distinct spatial distributions of the two beta receptor subtypes within the bulbar lamina. Beta-adrenergic receptors were located in both deep and superficial layers of the bulb. Specifically, beta 1 receptors were present in the granule cell, internal plexiform and glomerular layers. beta 2 receptors were present in the granule cell, internal plexiform, external plexiform, and glomerular layers. High levels of beta 2 receptors also were visible in the meningeal layers between the two bulbs. High densities of beta 1 and beta 2 adrenergic receptors were present within different sets of individual glomeruli by PND 12-19, and the number of these foci increased with age. The knowledge of beta-noradrenergic receptor localization in the bulb may provide the basis for understanding the action of norepinephrine on neural processes in the developing olfactory bulb.

Animals

Calcitonin and bisphosphonates treatment in bone loss after liver transplantation.

Osteopenia is a major complication of orthotopic liver transplantation (OLT). However, no effective therapy for bone disease has been defined. We have studied vertebral bone mineral density (VMD) and fasting serum markers of bone formation [bone gla protein (BGP), procollagen I carboxyterminal peptide (PICP)] and metabolism (serum Ca, P, intact parathyroid hormone (iPTH), 25OHD3 and 1,25(OH)2D3) in 120 patents after OLT. VMD was measured by dual-energy X-ray absorptiometry (DXA) using a Hologic QDR 1000 densitometer on two occasions, 12 months apart. Patients with OLT had a VBD significantly lower compared with age- and sexed-matched Spanish controls (P < 0.05). Prevalence of osteoporosis (Z score below -2 SD) was 35.8%. Serum BGP (8.6 +/- 0.7 ng/ml) and PICP (222.9 +/- 81.9 ng/dl) were higher than those of controls. However, serum calcium, phosphorus, iPTH, 25OHD3, and 1,25(OH)2D3 were within normal range. Patients with osteoporosis were randomly treated with 40 IU/day of calcitonin i.m. (Diatin, Ferrer Int. Laboratories) (n = 17) or 400 mg p.o., 15 days every 3 months, of sodium ethiodronate (Difosfen, Rubio Laboratories) (n = 23). All patients received 500 mg/12 hours of elemental calcium p.o. After 12 months of treatment, a significant increment of vertebral mineral density (VMD) was observed (6.4% and 8.2%, respectively). Serum BGP and PICP values remained elevated without a difference between the two drugs. Our results indicate that antiresorptive drugs may be of benefit in the high turnover osteoporosis of OLT recipients.

Adult

Focal 2-DG uptake persists following olfactory bulb lesions.

Exposure of rats to different odors produces spatially distinct patterns of 14C-2-deoxyglucose uptake (2-DG) in the glomerular layer of the main olfactory bulb. However, lesions of specific regions of the bulb that reliably contain 2-DG foci reportedly do not impair the ability of rats to perform olfactory-guided behaviors, suggesting that the lesioned olfactory bulb retains odor-responsiveness. Because the absence of focal 2-DG incorporation in lesioned olfactory bulbs has not been verified by 2-DG autoradiography, it cannot be concluded that focal responses in the olfactory bulb do not contribute to the encoding of olfactory information. To examine the effects of bulb lesions on 2-DG uptake in the olfactory bulb, we placed lesions in specific regions of the bulb that reliably contain 2-DG foci. We then exposed rats to odors 3 or 6 weeks later to determine if the lesions effectively eliminated focal 2-DG uptake in these bulbs. The results indicate that lesioned olfactory bulbs contain focal regions of 2-DG uptake in response to odor stimulation.

Animals

Venous hemodynamic abnormalities in patients with leg ulceration.

PURPOSE: Venous ulceration in the leg has been predominantly associated with deep venous insufficiency, although a few reports have implicated the superficial veins. The aim of this study was to identify the distribution of valvular incompetence in patients with active leg ulceration. PATIENTS AND METHODS: Color flow duplex imaging (CFDI) ultrasonography was used to evaluate the entire venous system--superficial, perforator and deep--from groin to ankle in 112 limbs of 94 patients with venous leg ulcers. RESULTS: Seventy two limbs (64%) had multisystem incompetence and 36 (32%) had one system involved only, whereas in 4 limbs (4%) there was no venous incompetence. Deep venous reflux exclusively was present in 7 limbs (6%) and the perforator system alone was involved only in 3 limbs (3%). However, isolated superficial incompetence was seen in 26 extremities (23%) and combination of superficial with perforator system alone in 23 (21%). In addition, reflux overall in the superficial system (alone and in combination with perforator and deep systems) was seen in 94 limbs (84%). The most common pattern (28%) of abnormality was reflux in all systems, superficial, perforator, and deep. CONCLUSIONS: The results of this study show that variable combined patterns account for over two thirds of patients with ulceration. No comprehensive surgical policy for alleviating ulceration can be justified; we suggest that a complete evaluation of all venous systems from groin to ankle with CFDI ultrasonography in patients with venous ulceration is practical on a routine basis and will be particularly valuable before surgery in order to target intervention at specific incompetent sites.

Adolescent

New insights into the pathophysiologic condition of venous ulceration with color-flow duplex imaging: implications for treatment?

PURPOSE: This study was conducted to investigate the distribution of reflux in the veins adjacent to or within the venous ulcer (local) and to correlate it with the pattern of disease of the axial veins (all veins away from the ulcer area) of the affected limb. METHODS: Forty-three ulcers in 34 legs of 33 patients were examined with color-flow duplex imaging. The veins in the area of the ulcer were scanned with a sterile technique. RESULTS: In 17 legs (50%) there was documented past deep venous thrombosis. All of the 34 limbs had reflux in the superficial or deep axial veins either alone or in combination. Fifteen of these limbs (44%) also had perforating vein incompetence, but none had perforator incompetence alone. Six ulcers showed no evidence of reflux in the local veins when scanned through the ulcer bed despite the presence of reflux in the axial veins of the limb. In 13 limbs with 17 ulcers, either the superficial axial veins alone or the deep axial veins alone were affected (with or without associated perforator incompetence). Examination of the local veins associated with these 17 ulcers revealed a similar pattern of reflux to that seen in the axial veins in 13 cases, with the remaining 4 ulcers showing no local venous abnormality. The pattern of reflux was less predictable at the local ulcer level in limbs where both superficial and deep venous incompetence coexisted in the axial veins. Only 7 of the 26 ulcers (27%) in these limbs had similar evidence of combined superficial and deep reflux in the local ulcer veins, whereas 10 ulcers (39%) were associated with local reflux in the superficial or deep veins alone. CONCLUSIONS: These data show that 86% (37/43) of the ulcers has some degree of reflux in the local area, the pattern of which may differ from the axial vein disease. Treatment of the local hemodynamic abnormalities may be an important factor in the healing of the ulcers and in the prevention of their recurrence.

Adolescent

Colour flow duplex scanning in suspected acute deep vein thrombosis; experience with routine use.

OBJECTIVES: To determine the accuracy of colour flow Duplex scanning (CFDS) in the diagnosis of deep vein thrombosis (DVT) and subsequently to investigate its diagnostic value in patients who have normal deep veins despite symptoms. DESIGN: Prospective open clinical study. SETTING: Vascular laboratory and radiology departments of University Hospital. MATERIALS AND METHODS: In the first part 112 limbs in 103 patients, 94 with symptoms of acute DVT and nine with pulmonary embolism (PE) were examined prospectively with CFDS and venography. Subsequently, in the second part, 328 legs in 304 patients were examined by CFDS alone for acute symptoms of DVT or PE. MAIN RESULTS: DVT was detected in 55 limbs by venography: proximal DVT was seen in 23 limbs, distal DVT in 25 limbs and both proximal and distal in seven limbs. CFDS was 100% sensitive and 98.8% specific in detecting proximal DVT whereas its sensitivity and specificity was 87.5% and 98.7% for distal DVT. Positive and negative predictive values were over 95% for both limb segments. The overall accuracy for the proximal DVT was 99.4% and for the distal 93.1%. In the second part, CFDS alone detected DVT in 156 limbs (47.6%); DVT was in the proximal segment in 82, distal segment in 61 and both in 13. In 172 limbs other causes of symptoms were identified in 34 (20%). CONCLUSIONS: We have demonstrated that CFDS is as accurate as venography when used by experienced operators. The average time of examination is 15-20 minutes and compares favourably with venography. Other causes of leg symptoms can also be diagnosed by CFDS in around 20% of patients who are found to have normal veins.

Humans

CLECOS_P: clinical evolution control system on Parkinsonian patients undergoing neural transplantation.

The CLECOS_P system was conceived for registering and automating the processing of clinical evaluations performed on patients with Parkinson's disease who undergo functional neurosurgery and/or neural transplant. CLECOS_P represents the first time a computerized system is able to offer--with high precision and considerable time-savings--an integral analysis of the evolutive behavior of the universe in integrated variables at the core assessment program for intracerebral transplantations (CAPIT). CAPIT is used internationally for the evaluation and follow-up of patients with this pathology who have undergone neural transplant. We used the so-called MEDSAC methodology for the preparation of this system. The methodology that was used for the design of an intelligent system aimed at medical decision-making was based on the quantitative analysis of the clinical evolution. At the present moment, there are 20 patients controlled by this system: 11 bilaterally transplanted, 9 unilaterally (registered in ranks of 3 months before operation up to 1, 2, 3, 6, 9, 12, 18, and 24 months after operation). The application of CLECOS_P to these patients permitted the evaluation of 400 clinical variables, where a better evolutive characterization of the patients was obtained, thus getting most favorable results with personalized therapeutic methods aimed at raising their quality of life. CLECOS_P is used in a multi-user environment on a local area network running Novell Netware version 3.11.

Brain Tissue Transplantation

Inter-series differences in the restenosis rate of Palmaz-Schatz coronary stent placement: differences in demographics and post-procedure lumen diameter.

Restenosis rates following Palmaz-Schatz stenting vary between 13 and 36%. To determine whether the nearly three-fold interseries difference in restenosis rates reflects systematic factors (demographic and procedural variables such as post-treatment lumen diameter) rather than random variation, we pooled 486 lesions treated with the Palmaz-Schatz coronary stent in the U.S. Multicenter Registry (n = 259) with the single-center Beth Israel Hospital experience (n = 227) and analyzed the combined series using a continuous geometric model of restenosis. A greater proportion of lesions (66 vs. 50%; P < 0.001) in the Multicenter cohort represented restenosis after a prior intervention. The Multicenter experience also showed a smaller minimum lumen diameter following stent placement (2.61 vs. 3.43 mm; P < 0.001), higher post-stent percent stenosis (16 vs. -2%; P < 0.001), and less acute gain (1.79 vs. 2.67 mm; P < 0.001) than lesions treated in the Beth Israel cohort. At 6-month follow-up, the angiographic restenosis rate (> or = 50% diameter stenosis) was significantly higher in the Multicenter group (35 vs. 27%; P = 0.05), despite the development of less absolute late loss (0.96 vs. 1.32 mm; P < 0.001). Multivariable modeling, however, showed that the only independent predictors of restenosis were a post-procedure lumen diameter < 2.80 mm (odds ratio = 1.57; P = 0.04), diabetes mellitus (odds ratio = 3.55; P < 0.001), and prior restenosis (odds ratio = 1.84; P = 0.008).(ABSTRACT TRUNCATED AT 250 WORDS)

Cohort Studies

Evidence of an oxidative challenge in the Alzheimer's brain.

Alzheimer's disease may arise from or produce oxidative damage in the brain. To assess the responses of the Alzheimer's brain to possible oxidative challenges, we assayed for glutathione, glucose-6-phosphate dehydrogenase, catalase and superoxide dismutase in twelve regions of Alzheimer's disease and aged control brains. In addition, we determined levels of malondialdehyde to evaluate lipid peroxidation in these brain regions. Most brain regions showed evidence of a response to an oxidative challenge, but the cellular response to this challenge differed among brain regions. These data suggest that the entire Alzheimer's brain may be subject to an oxidative challenge, but that some brain areas may be more vulnerable than others to the consequent neural damage that characterizes the disease.

Aged

Percutaneous excimer laser coronary angioplasty: results in the first consecutive 3,000 patients. The ELCA Investigators.

OBJECTIVES: We report the comprehensive results of the first consecutive 3,000 patients treated in an excimer laser coronary angioplasty registry. BACKGROUND: Excimer laser coronary angioplasty involves the use of a pulsed, 308-nm ultraviolet laser transmitted by optical fibers to reduce coronary stenoses. Preliminary reports have described safety and efficacy profiles in small numbers of patients. METHODS: Patients were enrolled in a prospective, nonrandomized manner. The catheters used were 1.3, 1.6, 2.0, 2.2 and 2.4 mm in diameter, at energy densities up to 70 mJ/mm2. Procedures were performed by standard angioplasty technique with conventional guide catheters. RESULTS: Seventy-five percent of patients were male, 68% were in Canadian Cardiovascular Society functional class III or IV and the cohort included 3,592 lesions. Procedural success (final stenosis < or = 50% without in-hospital Q wave myocardial infarction, coronary artery bypass surgery or death) was 90% and did not differ between the first 2,000 and the last 1,000 patients treated. There was no significant difference in success or complication rates with respect to lesion length, nor were there differences between selected complex and simple lesions. Complications included in-hospital bypass surgery (3.8%), Q wave myocardial infarction (2.1%) and death (0.5%). Coronary artery perforation occurred in 1.2% of patients (1% of lesions) but significantly decreased to 0.4% in the last 1,000 patients (0.3% of lesions). Angiographic dissection occurred in 13% of lesions, transient occlusion in 3.4% and sustained occlusion in 3.1%. Comprehensive lesion morphologic data collected in the latter portion of the study showed the procedure predominantly limited to American College of Cardiology-American Heart Association type B2 and C lesions, with no significant difference in short-term outcome between groups. CONCLUSIONS: Excimer laser angioplasty can be safely and effectively applied, even in a variety of complex lesions not well suited for percutaneous transluminal coronary angioplasty. These types may include aorto-ostial, long lesions, total occlusions crossable with a wire, diffuse disease and vein grafts. Most recent data show a trend for the selection of predominantly complex lesions and a reduction in the incidence of perforation. This procedure may broaden the therapeutic window for the interventional treatment of selected complex coronary artery disease.

Angioplasty, Balloon, Coronary

Venous reflux in patients with previous deep venous thrombosis: correlation with ulceration and other symptoms.

PURPOSE: Deep vein thrombosis (DVT) in many cases leads to chronic symptoms in the damaged leg, even though the affected veins have recanalized. The major hemodynamic defect in such recanalized veins is reflux. The incidence and extent of reflux has been studied in patients with proven DVT and correlated with concurrent symptoms. METHODS: Two hundred seventeen limbs in 183 patients were examined by duplex scanning from January 1989 to October 1992. All limbs had previous DVT diagnosed by venography. Sites and extent (proximal, distal, or both) of reflux were identified by meticulous duplex scanning of the whole venous system and correlated with presenting symptoms. RESULTS: The patients were classified into nine groups on the basis of the classification of the system involved (superficial, deep, or superficial and deep) and whether the reflux was found proximal or distal to the knee or both. Eight-one limbs belong to chronic venous insufficiency class 1, 92 belong to class 2, and 38 belong to class 3. Reflux was confined to the deep venous system in 84 limbs (38.7%), to the superficial system in 31 (14.3%) limbs, and to both systems in 102 (47%) limbs. It was confined to proximal veins only in 48 (22.1%) limbs, distal only in 56 (25.8%) limbs and throughout the limb in 113 (52.1%) limbs. The incidence of swelling was increased by distal or a combination of proximal and distal reflux regardless of which system was involved. In limbs with superficial venous insufficiency (SVI) or deep venous insufficiency (DVI) only, the incidence of skin changes was not affected by the extent of reflux. However, in limbs with combined SVI and DVI, it was increased in the presence of reflux throughout the limb. Absence of distal reflux was associated with a low incidence of skin changes even in the presence of DVI. Ulceration increased with an increased extent of reflux in the presence of SVI. Absence of superficial reflux was associated with a low incidence, even in the presence of DVI. CONCLUSIONS: The data suggest that as far as the skin changes and ulceration are concerned, distal reflux and reflux in the superficial veins are more harmful than reflux confined to the deep veins, even when such reflux extends throughout the deep venous system.

Adolescent

Superficial venous insufficiency: correlation of anatomic extent of reflux with clinical symptoms and signs.

PURPOSE: The aim of this study was to assess the distribution and extent of valvular incompetence in patients with reflux confined to the superficial venous system and correlate the extent of such reflux with clinical symptoms and signs. METHODS: Two hundred fifty-five limbs of 217 patients with superficial venous insufficiency and normal perforating and deep veins were examined with color-flow duplex imaging. One hundred twenty-three limbs (48.2%) of 102 patients had reflux confined to the long saphenous system, 83 limbs (32.6%) of 72 patients had reflux confined to the the short saphenous system, and 49 limbs (19.2%) of 43 patients had reflux in both long and short saphenous systems. RESULTS: In the long saphenous system the commonest pattern of reflux was that which extended throughout the length of long saphenous vein (LSV) (47%). Ache, swelling, and skin changes were common in the presence of below knee reflux irrespective whether the thigh segment was involved. Ulceration (8%) was found only in limbs with reflux extending throughout the length of LSV. In the short saphenous system the most common pattern of reflux extended throughout the length of short saphenous vein (SSV) (57%) without involvement of Giacomini or gastrocnemial veins. Ache and swelling were present in 62% and 72% of the limbs, but this incidence was not related to the extent of reflux. Swelling, skin changes, and ulceration occurred only when the whole of the SSV was involved. In the limbs with reflux in both the long and short saphenous systems, the most common pattern of reflux extended throughout the length of both systems (45%). In these limbs the incidence of swelling was 80%. The incidence of skin changes went from 44% when the below-knee segment of the LSV was involved to 73% when reflux occurred throughout the LSV and SSV. Ulceration (14%) was found only in the latter situation. Variable patterns of saphenogastrocnemial termination were seen. In 57.8% of the limbs SSV joined the popliteal vein just above the popliteal crease, whereas the SSV terminated in the thigh in 26.6%. CONCLUSIONS: We conclude that ache, ankle edema, and skin changes in limbs with reflux confined to the superficial venous system are predominantly associated with reflux in the below-knee veins. Ulceration is found only when the whole of the LSV is involved (8%) or when reflux is extensive in both LSV and SSV (14%).

Adolescent

Bone density and turnover in Addison's disease: effect of glucocorticoid treatment.

Osteoporosis is a well-known side-effect of chronic treatment with glucocorticoids. We have studied vertebral bone mineral density (BMD) and biochemical markers of bone metabolism in 30 patients diagnosed of Addison's disease (AD) to determine the effect of long-term replacement treatment with hydrocortisone (30 mg/day) or prednisone (7.5 mg/day). Lumbar bone mineral density was measured with dual energy X-ray absorptiometry in L-1-4 in two occasions, separated by 12 months. BMD in premenopausal women and men with AD was similar to healthy controls and postmenopausal women had slightly lower results. Rate of change of bone density followed up over a period of 12 months was -0.82%. Bone loss was not influenced by duration or type of steroid treatment. Biochemical parameters, serum calcium, alkaline phosphatase, osteocalcin, procollagen type I, PTH and 25(OH)vitamin D were within normal limits. Our results show that in patients with AD, after replacement with low doses of glucocorticoids there is no significative trabecular bone loss neither modifications in bone formation markers.

Absorptiometry, Photon

Absence of high anion gap metabolic acidosis in severe ethylene glycol poisoning: a potential effect of simultaneous lithium carbonate ingestion.

Ethylene glycol poisoning is accompanied by a high anion gap metabolic acidosis. We describe a case of severe ethylene glycol poisoning in which severe acidosis was not present. This appears to be due to a beneficial effect exerted by simultaneous ingestion of 80 lithium carbonate tablets, each containing approximately 4 mEq carbonate, with a potential bicarbonate load of 320 mEq. We postulate a protective effect of lithium carbonate due to the bicarbonate generated by this substance.

Acid-Base Equilibrium