OBJECTIVE: To investigate the effects of acid-sensing ion channels (ASICs) on electrophysiological epileptic activities of mouse hippocampal pyramidal neurons in the extracellular acidotic condition. METHODS: We investigated effects of extracellular acidosis on epileptic activities induced by elevated extracellular K concentration or the application of an antagonist of GABA receptors in perfusate of mouse hippocampal slices under field potential recordings. We also tested the effects of extracellular acidosis on neuronal excitability under field potential recording and evaluated the changes in epileptic activities of the neurons in response to pharmacological inhibition of ASICs using a specific inhibitor of ASICs. RESULTS: Extracellular acidosis significantly suppressed epileptic activities of the hippocampal neurons by converting ictal-like epileptic activities to non-ictal-like epileptic activities in both high [K ]o and disinhibition models, and also suppressed the intrinsic excitability of the neurons. ASICs inhibitor did not antagonize the inhibitory effect of extracellular acidosis on ictal epileptic activities and intrinsic neuronal excitability, but exacerbated non-ictal epileptic activities of the neurons in extracellular acidotic condition in both high [K]o and disinhibition models. CONCLUSIONS ASICs can differentially modulate ictal-like and non-ictallike epileptic activities via its direct actions on excitatory neurons.
Acid Sensing Ion Channels ; metabolism ; Acidosis ; Animals ; Epilepsy ; physiopathology ; Hydrogen-Ion Concentration ; Mice ; Pyramidal Cells ; pathology ; physiology

Succinyl-CoA:3-ketoacid CoA transferase (SCOT) deficiency is a rare inborn error of ketone body utilization, characterized by episodic or permanent ketosis. SCOT deficiency is caused by mutations in the OXCT1 gene, which is mapped to 5p13 and consists of 17 exons. A 12-month-old girl presented with severe ketoacidosis and was treated with continuous renal replacement therapy. She had two previously unrecognized mild-form episodes of ketoacidosis followed by febrile illness. While high levels of ketone bodies were found in her blood and urine, other laboratory investigations, including serum glucose, were unremarkable. We identified novel compound heterozygous mutations in OXCT1:c.1118T>G (p.Ile373Ser) and a large deletion ranging from exon 8 to 16 through targeted exome sequencing and microarray analysis. This is the first Korean case of SCOT deficiency caused by novel mutations in OXCT1, resulting in life-threatening ketoacidosis. In patients with unexplained episodic ketosis, or high anion gap metabolic acidosis in infancy, an inherited disorder in ketone body metabolism should be suspected.
Acid-Base Equilibrium ; Acidosis ; Blood Glucose ; Exome ; Exons ; Female ; Humans ; Infant ; Ketone Bodies ; Ketosis ; Metabolism ; Microarray Analysis ; Renal Replacement Therapy ; Transferases

BACKGROUND: Information on biochemical changes following rapid transfusion of blood mixtures in liver transplantation patients is limited. METHODS: A blood mixture composed of red blood cells, fresh frozen plasma, and 0.9% saline was prepared in a ratio of 1 unit:1 unit:250 ml. During massive hemorrhage, 300 ml of the blood mixture was repeatedly transfused. A blood mixture sample as well as pre- and post-transfusion arterial blood samples were collected at the first, third, fifth, and seventh bolus transfusions. Changes in pH, hematocrit, electrolytes, and glucose were measured with a point-of-care analyzer. The biochemical changes were described, and the factors driving the changes were sought through linear mixed effects analysis. RESULTS: A total of 120 blood samples from 10 recipients were examined. Potassium and sodium levels became normalized during preservation. Biochemical changes in the blood mixture were significantly related to the duration of blood bank storage and reservoir preservation (average R2 = 0.41). Acute acidosis and hypocalcemia requiring immediate correction occurred with each transfusion. Both the pre-transfusion value of the patient and the blood mixture value were significant predictors of post-transfusion changes in the body (average R2 = 0.87); however, the former was more crucial. CONCLUSIONS: Rapid infusion of blood mixture is relatively safe because favorable biochemical changes occur during storage in the reservoir, and the composition of the blood mixture has little effect on the body during rapid transfusion in liver recipients. However, acute hypocalcemia and acidosis requiring immediate correction occurred frequently due to limited citrate metabolism in the liver recipients.
Acidosis ; Blood Banks ; Blood Safety ; Blood Transfusion ; Citric Acid ; Electrolytes ; Erythrocytes ; Glucose ; Hematocrit ; Hemorrhage ; Humans ; Hydrogen-Ion Concentration ; Hypocalcemia ; Liver Transplantation* ; Liver* ; Metabolism ; Plasma ; Point-of-Care Systems ; Potassium ; Sodium

Taurine is an abundant, β-amino acid with diverse cytoprotective activity. In some species, taurine is an essential nutrient but in man it is considered a semi-essential nutrient, although cells lacking taurine show major pathology. These findings have spurred interest in the potential use of taurine as a therapeutic agent. The discovery that taurine is an effective therapy against congestive heart failure led to the study of taurine as a therapeutic agent against other disease conditions. Today, taurine has been approved for the treatment of congestive heart failure in Japan and shows promise in the treatment of several other diseases. The present review summarizes studies supporting a role of taurine in the treatment of diseases of muscle, the central nervous system, and the cardiovascular system. In addition, taurine is extremely effective in the treatment of the mitochondrial disease, mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS), and offers a new approach for the treatment of metabolic diseases, such as diabetes, and inflammatory diseases, such as arthritis. The review also addresses the functions of taurine (regulation of antioxidation, energy metabolism, gene expression, ER stress, neuromodulation, quality control and calcium homeostasis) underlying these therapeutic actions.
Acidosis, Lactic ; Arthritis ; Brain Diseases ; Calcium ; Cardiovascular System ; Central Nervous System ; Cytoprotection ; Energy Metabolism ; Gene Expression ; Heart Failure ; Japan ; MELAS Syndrome ; Metabolic Diseases ; Mitochondrial Diseases ; Neurodegenerative Diseases ; Pathology ; Quality Control ; Taurine*

Recurrent acute pancreatic attacks is a rare clinical condition (2-5% of all acute pancreatis) in children and is mainly idiopathic in most cases. Sometimes it may be associated with congenital anomalies, metabolic diseases or hereditary conditions. Isovaleric acidemia (IVA) is a rare autosomal recessive amino acid metabolism disorder associated with isovaleryl coenzyme A dehydrogenase deficiency presenting the clinical findings such metabolic acidosis with increased anion gap, hyperammonemia, ketonemia, hypoglycemia, “the odor of sweaty feet,” abdominal pain, vomiting, feeding intolerance, shock and coma. Recurrent acute pancreatitis associated with IVA have been rarely reported. Herein; we report a child who admitted with recurrent acute pancreatic attacks and had the final diagnosis of IVA. Mutation analysis revealed a novel homozygous mutation of (p.E117K [c.349G>A]) in the IVA gene. Organic acidemias must kept in mind in the differential diagnosis of recurrent acute pancreatic attacks in children.
Abdominal Pain ; Acid-Base Equilibrium ; Acidosis ; Child* ; Coma ; Diagnosis ; Diagnosis, Differential ; Humans ; Hyperammonemia ; Hypoglycemia ; Isovaleryl-CoA Dehydrogenase ; Ketosis ; Metabolic Diseases ; Metabolism ; Odors ; Pancreatitis* ; Shock ; Vomiting

OBJECTIVETo explore the value of urine gas chromatography-mass spectrometry (GC-MS) in the screening of children at risk of inherited metabolic diseases (IMD), and to identify the disease spectrum of IMD and the clinical characteristics of children with IMD.

METHODSThe clinical data of 15 851 children at risk of IMD who underwent urine GC-MS in the Tianjin Children's Hospital between February 2012 and December 2016 were retrospectively analyzed.

RESULTSIn the 15 851 children, 5 793 (36.55%) were detected to have metabolic disorders. A total of 117 (0.74%) children were confirmed to have IMD, including 77 cases of methylmalonic acidemia (65.8%). The clinical manifestations of confirmed cases in the neonatal period mainly included jaundice, metabolic acidosis, abnormal muscular tension, feeding difficulty, poor response, and lethargy or coma. The clinical manifestations of confirmed cases in the non-neonatal period mainly included delayed mental and motor development, metabolic acidosis, convulsion, recurrent vomiting, and anemia.

CONCLUSIONSGC-MS is an effective method for the screening for IMD in children at risk. Methylmalonic acidemia is the most common IMD. The clinical manifestations of IMD are different between the confirmed cases in the neonatal and non-neonatal periods.

Acidosis ; etiology ; Adolescent ; Amino Acid Metabolism, Inborn Errors ; complications ; diagnosis ; Child ; Child, Preschool ; Developmental Disabilities ; etiology ; Female ; Gas Chromatography-Mass Spectrometry ; Humans ; Infant ; Infant, Newborn ; Male ; Metabolism, Inborn Errors ; complications ; diagnosis ; Retrospective Studies ; Risk

Cerebral ischemia is caused by arterial occlusion due to a thrombus or an embolus. Such occlusion induces multiple and concomitant pathophysiological processes that involve bioenergetic failure, acidosis, loss of cell homeostasis, excitotoxicity, and disruption of the blood-brain barrier. All of these mechanisms contribute to neuronal death, mainly via apoptosis or necrosis. The immune system is involved in this process in the early phases after brain injury, which contributes to potential enlargement of the infarct size and involves the penumbra area. Whereas inflammation and the immune system both exert deleterious effects, they also contribute to brain protection by stimulating a preconditioning status and to the concomitant repair of the injured parenchyma. This review describes the main phases of the inflammatory process occurring after arterial cerebral occlusion, with an emphasis on the role of single mediators.
Acidosis ; Apoptosis ; Blood-Brain Barrier ; Brain ; Brain Injuries ; Brain Ischemia ; Embolism ; Energy Metabolism ; Homeostasis ; Immune System ; Inflammation* ; Necrosis ; Neurons ; Stroke* ; Thrombosis

Pesticide formulation includes solvents (methanol and xylene) and antifreeze (ethylene glycol) whose metabolites are anions such as formic acid, hippuric acid, and oxalate. However, the effect of the anion gap on clinical outcome in acute pesticide intoxication requires clarification. In this prospective study, we compared the anion gap and other parameters between surviving versus deceased patients with acute pesticide intoxication. The following parameters were assessed in 1,058 patients with acute pesticide intoxication: blood chemistry (blood urea nitrogen, creatinine, glucose, lactic acid, liver enzymes, albumin, globulin, and urate), urinalysis (ketone bodies), arterial blood gas analysis, electrolytes (Na+, K+, Cl- HCO3 -, Ca++), pesticide field of use, class, and ingestion amount, clinical outcome (death rate, length of hospital stay, length of intensive care unit stay, and seriousness of toxic symptoms), and the calculated anion gap. Among the 481 patients with a high anion gap, 52.2% had a blood pH in the physiologic range, 35.8% had metabolic acidosis, and 12.1% had acidemia. Age, anion gap, pesticide field of use, pesticide class, seriousness of symptoms (all P < 0.001), and time lag after ingestion (P = 0.048) were significant risk factors for death in univariate analyses. Among these, age, anion gap, and pesticide class were significant risk factors for death in a multiple logistic regression analysis (P < 0.001). In conclusions, high anion gap is a significant risk factor for death, regardless of the accompanying acid-base balance status in patients with acute pesticide intoxication.
Acid-Base Equilibrium ; Acidosis/etiology ; Adolescent ; Adult ; Aged ; Aged, 80 and over ; Anions/*chemistry/metabolism ; Biomarkers/*chemistry/metabolism ; Blood Gas Analysis ; Chemically-Induced Disorders/mortality/pathology ; Electrolytes/analysis ; Female ; Humans ; Intensive Care Units ; Logistic Models ; Male ; Middle Aged ; Odds Ratio ; Pesticides/*poisoning ; Prospective Studies ; Risk Factors ; Survival Analysis ; Urinalysis ; Young Adult

Polyethylene glycol (PEG)-3350 is the most frequently used lavage solution for bowel cleansing prior to colonoscopy or elective surgery because its large molecular weight means that it is poorly absorbed. However, if it leaks into the peritoneal cavity, complications may arise. Few published studies have assessed the absorption, distribution, metabolism and excretion of PEG. Moreover, no published clinical data regarding complications due to the intra-peritoneal leakage of PEG-3350 could be found. We report on an elderly patient who developed the poisoning caused by leaking of PEG-3350 during bowel preparation. It resulted in severe metabolic acidosis, hypernatremia, hyperosmolality and a high anion gap, but it was effectively treated with early continuous renal replacement therapy after surgery.
Absorption ; Acid-Base Equilibrium ; Acidosis ; Aged* ; Colonoscopy ; Humans ; Hypernatremia ; Metabolism ; Molecular Weight ; Peritoneal Cavity ; Poisoning* ; Polyethylene Glycols* ; Renal Replacement Therapy ; Therapeutic Irrigation

Polyethylene glycol (PEG)-3350 is the most frequently used lavage solution for bowel cleansing prior to colonoscopy or elective surgery because its large molecular weight means that it is poorly absorbed. However, if it leaks into the peritoneal cavity, complications may arise. Few published studies have assessed the absorption, distribution, metabolism and excretion of PEG. Moreover, no published clinical data regarding complications due to the intra-peritoneal leakage of PEG-3350 could be found. We report on an elderly patient who developed the poisoning caused by leaking of PEG-3350 during bowel preparation. It resulted in severe metabolic acidosis, hypernatremia, hyperosmolality and a high anion gap, but it was effectively treated with early continuous renal replacement therapy after surgery.
Absorption ; Acid-Base Equilibrium ; Acidosis ; Aged ; Colonoscopy ; Humans ; Hypernatremia ; Metabolism ; Molecular Weight ; Peritoneal Cavity ; Poisoning ; Polyethylene Glycols ; Renal Replacement Therapy ; Therapeutic Irrigation