Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085584 (encephalopathy)
 18,178 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied the plasma amino acid profiles in the postabsorptive period in three groups of cirrhotic patients: stable, unstable, and with acute portal systemic encephalopathy (PSE), and compared them with a healthy control group in order to investigate the differences among the different groups and reevaluate the use of the branched-chain amino acid/aromatic amino acid (BCAA/AAA) ratio. Although plasma amino acid levels were similar to the control group, stable cirrhotics had a significantly decreased BCAA/AAA ratio (2.9 +/- 0.2) compared to the control group (3.9 +/- 0.3) (p < 0.05). Unstable cirrhotics had differences in plasma amino acid levels and the BCAA/AAA ratio was even lower (1.7 +/- 0.3) compared with stable cirrhotics and controls, respectively (p < 0.05 and p < 0.01). Patients with PSE had extreme elevations of most amino acids and showed the lowest BCAA/AAA ratio of all four groups (0.8 +/- 0.07) (p < 0.001 compared with controls). We conclude that it is possible to detect differences in plasma amino acid concentrations in different groups of cirrhotics, and that the BCAA/AAA ratio is a good index for the assessment of liver impairment. The latter could be used in the follow-up of a selected group of patients such as those undergoing major surgery or liver transplantation in whom the BCAA/AAA ratio could be used to help determine the best time for the transplant.
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PMID:The BCAA/AAA ratio of plasma amino acids in three different groups of cirrhotics. 148 30

Serum amino acid determinations were made in 40 patients with chronic cor pulmonale in the period of 1985-1987 in our hospital. There were slight type 14 cases. severe type 26 cases (including pulmonary encephalopathy 10 cases). In severe type the ratio of branched chain amino acid to aromatic amino acid (BACC/AAA) was significantly lower than normal (P less than 0.01) and there was significant negative correlation between PaCO2 and BCAA/AAA (r = -0.49 P less than 0.05). The plasma amino acid pattern in severe type cor pulmonale is similar to that found in hepatic encephalopathy. The mechanism of coma in cor pulmonale is at least in some degree, similar with that of hepatic encephalopathy.
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PMID:[Plasma amino acid changes in 40 cases of chronic cor pulmonale]. 263 32

There are widespread disturbances in hepatic and peripheral metabolism in sepsis. Prominent effects include elevated plasma concentrations of aromatic and sulfur-containing amino acids during sepsis, while BCAA are normal or reduced. These alterations probably in part reflect accelerated muscle protein breakdown and hepatic dysfunction. Concomitant with changes in plasma amino acids, altered brain levels of amino acids and neurotransmitters are observed. Increased brain concentrations of the serotoninergic and reduced levels of the catecholaminergic neurotransmitters, along with the occurrence of false neurotransmitters, may be important factors in the pathophysiology of septic encephalopathy. Although the main objective in the treatment of septic patients, of course, is to remove or drain the septic focus, recent studies have shown that administration of BCAA-enriched solutions may be beneficial in the improvement of metabolic derangements and septic encephalopathy. It should be emphasized that not a great deal of work has been done in this area, and the above results are preliminary and fragmentary. However, they do at least provide a working hypothesis for testing of another form of metabolic encephalopathy.
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PMID:Septic encephalopathy. Etiology and management. 287 41

In a controlled cross-over trial, we have compared a conventional 40-g protein diet (30 g animal and 10 g vegetable, diet A) with an 80-g vegetable-protein-supplemented diet (30 g animal and 50 g vegetable, diet B) in the treatment of six patients with chronic stable portal systemic encephalopathy, requiring dietary and lactulose therapy. Each diet was given, in random order, for 5 days in hospital. EEG, clinical indices of encephalopathy, and the plasma amino acid profile were assessed at the end of each treatment period. The increase in vegetable protein intake was associated with minor improvement in EEG and clinical performance in two patients, and no change in the others. Fasting plasma phenylalanine and tyrosine were higher on diet B [phenylalanine 108.6 +/- 9.3 (SEM) mumol/L versus 99.6 +/- 8.37, p less than 0.05 (paired t test); tyrosine 153 +/- 15.2 mumol/L versus 140 +/- 14, p less than 0.05). The plasma branched-chain amino acid levels did not change, and the branched chain/aromatic amino acid ratio (BCAA/AAA) was lower on diet B (p less than 0.02). Fecal weights were not significantly altered. These results indicate that patients with chronic portal systemic encephalopathy are tolerant of protein supplementation from vegetable sources. A minor improvement in parameters of encephalopathy was seen in some individuals, despite a lowering of BCAA/AAA which some investigators have thought important in the pathogenesis of encephalopathy.
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PMID:Dietary protein supplementation from vegetable sources in the management of chronic portal systemic encephalopathy. 639 Nov 54

The method of constant infusion of U14C tyrosine tracer was used to measure whole body protein turnover in 24 patients with liver disease of varying severity. Whilst on a basic diet of glucose alone (5 g/hr), protein turnover and endogenous breakdown was significantly elevated in patients with cirrhosis and fulminant hepatic failure (F.H.F.), breakdown rising to 700 g/d greater than normal in F.H.F. In addition plasma aromatic aminoacids were significantly elevated and positively associated with the increases in endogenous protein breakdown (r = 0.78, p less than 0.05). Fourteen patients had a second infusion after dietary supplementation with either complete aminoacids (3 g/hr, n = 8) or branched chain aminoacids (BCAA, 4 g/hr, n = 6). The complete mixture did not worsen encephalopathy, improved the plasma aminoacid pattern, reduced protein breakdown and resulted in positive aminoacid balance. The BCAA supplements significantly reduced protein oxidation and endogenous breakdown. The results indicate that protein restriction in cirrhosis and fulminant hepatic failure will not significantly affect the load of aminoacids on the liver, nor their accumulation in plasma. Nutritional support of such patients should therefore include 40 - 60 g. protein per day to prevent protein depletion, and hypertonic glucose and insulin to suppress catabolism. BCAA supplementation may play a useful supportive role in increasing the utilisable nitrogen content of the diet and further suppressing catabolism.
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PMID:Protein turnover in acute and chronic liver disease. 679 9

Previous reports based on studies in brain tissue from humans and experimental animals suggest that aromatic amino acids (AAAs) and branched-chain amino acids (BCAA's) accumulate in brain in acute liver failure. In order to assess these changes in relation to the severity of neurological impairment and to the degree of hyperammonemia, AAAs and BCAAs were measured in vivo by cerebral microdialysis in frontal cortex of rats at various stages during the development of hepatic encephalopathy due to acute liver failure resulting from portacaval anastomosis followed by hepatic artery ligation. Extracellular brain concentrations of AAAs and of valine and leucine were elevated 2 to 4-fold following hepatic devascularization and these increases were significantly correlated to arterial ammonia concentration (r= 0.71-0.84, p<0.05). Extracellular concentrations of tyrosine paralleled the deterioration of neurological status in acute liver failure rats. In view of their role as precursors of monoamine neurotransmitters, ammonia-induced alterations of intracellular/extracellular brain concentration ratios for AAAs could account for altered neuronal excitability and contribute to the encephalopathy characteristic of acute liver failure.
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PMID:Selective increases of extracellular brain concentrations of aromatic and branched-chain amino acids in relation to deterioration of neurological status in acute (ischemic) liver failure. 947 99

Hyperammonemia and severe amino acid imbalances play central role in hepatic encephalopathy (HE). In the article is demonstrated that the main source of ammonia in cirrhotic subjects is activated breakdown of glutamine (GLN) in enterocytes and the kidneys and the main source of GLN is ammonia detoxification to GLN in the brain and skeletal muscle. Branched-chain amino acids (BCAA; valine, leucine, and isoleucine) decrease due to activated GLN synthesis in muscle. Aromatic amino acids (AAA; phenylalanine, tyrosine, and tryptophan) and methionine increase due to portosystemic shunts and reduced ability of diseased liver. The effects on aminoacidemia of the following variables that may affect the course of liver disease are discussed: nutritional status, starvation, protein intake, inflammation, acute hepatocellular damage, bleeding from varices, portosystemic shunts, hepatic cancer, and renal failure. It is concluded that (1) neither ammonia nor amino acid concentrations correlate closely with the severity of liver disease; (2) BCAA/AAA ratio could be used as a good index of liver impairment and for early detection of derangements in amino acid metabolism; (3) variables potentially leading to overt encephalopathy exert substantial but uneven effects; and (4) careful monitoring of ammonia and aminoacidemia may discover important break points in the course of liver disease and indicate appropriate therapeutic approach. Of special importance might be isoleucine deficiency in bleeding from varices, arginine deficiency in sepsis, and a marked rise of GLN and ammonia levels that may appear in all events leading to HE.
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PMID:Ammonia and amino acid profiles in liver cirrhosis: effects of variables leading to hepatic encephalopathy. 2522 Aug 75

Minimal hepatic encephalopathy (mHE) is common among patients with cirrhotic liver disease and causes significant morbidity and mortality. It may present as cognitive impairment, behavioural changes and, less frequently, with neurological symptoms which make diagnosis of the disease challenging. A history of falls and accidents may also be suggestive of mHE. Diagnosis primarily relies on at least two positive psychometric tests of which the psychometric hepatic encephalopathy score (PHES) is essential. Alternatively, PHES and an electroencephalogram may be used to establish a diagnosis. Biochemical markers of encephalopathy currently have no role in the diagnosis of mHE. Treatment is not always advocated for a diagnosis of mHE but is dependent on the degree of impairment caused by the symptoms. After treatment of other metabolic abnormalities and co-morbidities associated with cirrhosis, more specific treatment for mHE largely relies on therapies used to lower ammonia levels. Laxatives and rifaximin are commonly used in treatment and work through decreasing ammonia absorption from the gut. Other therapies, such as BCAA, LOLA, L-carnitine and phenylbutyrate, modify responses to ammonia as well as enhancing metabolism and excretion. mHE resulting from spontaneous portosystemic shunts or transhepatic intraportal systemic shunts may require ablation or reduction of the shunt. Early detection and appropriate treatment of mHE is important to prevent significant cognitive impairments and progression to overt HE.
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PMID:Diagnosis and Treatment of Low-Grade Hepatic Encephalopathy. 2615 74