Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0432222 (SEM)
 47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Utilizing a specific and sensitive radioimmunoassay, palsma and urine tyramine were measured in 14 consecutive patients with liver biopsy-proven Reye's syndrome. Plasma tyrosine was measured in 11 of these patients. The results revealed significant (P less than .003) elevation in plasma (3.4 +/- .52 ng/ml) (mean +/- SEM) and urine (1.00 +/- .26 mg/24 hr) tyramine as well as plasma tyrosine (204 +/- 52.5 mumole/liter) at the onset of the disease when compared to the levels of tyramine and tyrosine in a group of hospitalized patients without hepatic disorders. Furthermore, there was a positive correlation between plasma tyramine and days in coma (r = .86; P less than .001), and between plasma tyramine and tyrosine (r = 0.80; P less than .001). These data suggest that there is s substantial disturbance of tyrosine metabolism in Reye's syndrome and that the accumulation of this amino acid and its metabolite, tyramine, may contribute to the encephalopathy of this disease.
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PMID:Evidence for hypertyraminemia in Reye's syndrome. 45 May 66

beta-Oxidation of [1-14C]palmitic acid was examined in homogenates of astrocytes cultured from neonatal mouse brain. Under optimal reaction conditions (< or = 50 micrograms protein, 10 min at 37 degrees C), oxidation increased as a function of palmitate concentration (15 microM to 2 mM) and reached a maximum rate of 1.98 +/- 0.29 nmol/min/mg protein (mean +/- SEM) at 0.2 mM substrate. Eadie-Hofstee analysis of data from four experiments yielded apparent values for Vmax of 1.87 nmol/min/mg protein, and for Km, 35-40 microM. There were no dramatic changes in the oxidation rate in cells between 10 and 36 days in culture. During the 10-min assays, less than 0.05% of the radioactivity was converted to 14CO2 by the astrocytes; water-soluble products accounted for 1-2% of the total substrate added. Studies with KCN indicated that 60-70% of the total activity occurred in the mitochondria. We have been studying the structural and functional changes associated with the cerebral encephalopathy of Reye's syndrome (RS). Three-week-old astrocytes exposed to serum from RS children for the final 7 days of culture exhibited minor mitochondrial pleomorphism and had increased numbers of other intracellular organelles. Examination of the effects of agents implicated in RS indicated that oxidation of [1-14C]palmitate was not altered by Na+ salicylate (1-3 mM), but was inhibited by the industrial surfactant, Toximul MP-8 (> or = 10 micrograms/ml), 4-pentenoic acid (> or = 0.1 microM), or with 4 days' exposure to ammonia (10 nM). The latter treatment also resulted in an increase in protein synthesis, cell volume, and malondialdehyde formation. These results suggest that some of the "toxins" implicated in RS inhibit fatty-acid oxidation in the astrocytes and produce other lipid-related abnormalities that could be related to encephalopathy.
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PMID:Beta-oxidation of [1-14C]palmitic acid by mouse astrocytes in primary culture: effects of agents implicated in the encephalopathy of Reye's syndrome. 146 46

Advanced hepatic injury can be identified by the appearance of jaundice, coagulopathy, or encephalopathy but these conditions are late, irreversible findings and represent the end stage of a long insidious process. Currently available methods for assessing "liver function" (SGOT, SGPT, GGT, LDH, etc.) do not actually measure liver function. In this study we prospectively evaluated "true" liver function in patients undergoing porto-systemic shunt. Effective hepatic blood flow [low dose galactose clearance (EHBF)], hepatocyte transport (theophylline levels at 24 hr), and hepatic conjugation ability [acetaminophen metabolism to its glucuronide and sulfate conjugates ( (S + G)/A) and acetaminophen remaining at 24 hr (A24)] were measured in normal males (NL) and in patients pre- and post-8-mm H-graft portacaval shunt (PCS). All data are means +/- SEM, analyzed by Student's t test, and significance was accepted if P less than 0.05. There were no significant differences in EHBF even after PCS. Hepatocyte transport was decreased in pre-op (1.43 +/- 0.16 vs 0.74 +/- 0.08) and post-op (1.79 +/- 0.34) PCS patients. Hepatic conjugating ability was also decreased in pre-op PCS patients [A24 was increased (0.24 +/- 0.11 vs 0.01 +/- 0.01) while the ratio of conjugation products to acetaminophen remained the same]. The ability of the liver to conjugate substrate was severely compromised postoperatively [A24 - 1.27 +/- 0.67, (S + G)/A - 1.19 +/- 0.34]. We believe that changes in liver function can be accurately measured using these noninvasive methods, and in using these methods we have identified altered hepatocyte transport and conjugating ability in patients undergoing porto-systemic shunt surgery.
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PMID:Hepatic function after porto-systemic shunt. 174 Sep 38

Aluminum toxicity is a documented cause of encephalopathy, anemia, and osteomalacia. Excretion is primarily renal; therefore, patients with renal insufficiency are at risk for aluminum accumulation and toxicity. This has been demonstrated in uremic children treated with aluminum-containing antacids. The purpose of this study was to determine whether plasma aluminum levels were elevated in infants with normal renal function during prolonged aluminum-containing antacid use. Ten study infants (mean age = 5.8 months), who had been receiving antacids for at least 1 week, were compared with 16 control infants (mean age = 9.8 months) not receiving antacids. The study patients consumed 123 +/- 16 mg/kg per day (mean +/- SEM) of elemental aluminum for an average of 4.7 weeks. Their plasma aluminum level (37.2 +/- 7.13 micrograms/L) was significantly greater than that of the control group (4.13 +/- 0.66 micrograms/L) (P less than .005). It is concluded that plasma aluminum levels may become elevated in infants with normal renal function who are consuming high doses of aluminum-containing antacids. The safety of antacids containing aluminum should not be assumed and they should be used judiciously in infants, with careful monitoring of the aluminum dose and plasma level.
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PMID:Elevated plasma aluminum levels in normal infants receiving antacids containing aluminum. 198 26

Cerebral circulation and metabolism in septic encephalopathy have not been well documented. The authors measured cerebral blood flow (CBF) and metabolic rate for oxygen (CMRO2) in six patients with septic encephalopathy associated with multiple organ failure (three to five organs). They found that CBF and CMRO2 were significantly lower than awake control values of 46 +/- 2 to 28 +/- 3 mL/100g/min (mean +/- SEM) and 3.1 +/- 0.2 to 1.2 +/- 0.2 mL/100g/min, respectively. Cerebral vascular resistance (CVR) and cerebral circulatory index (CCI:CBF/CMRO2) were significantly higher than the control values of 2.0 +/- 0.1 to 3.0 +/- 0.4 mm Hg/mL/100g/min and 15.1 +/- 0.8 to 24.2 +/- 3.3, respectively. At the time of cerebral circulatory and metabolic measurements, their consciousness varied between 4 and 10 as evaluated by the Glasgow coma scale. The electroencephalogram showed diffuse slow wave activity and the latency of the auditory brain stem evoked response was prolonged in four of six patients. Computed brain tomography showed either no abnormality or mild atrophy. It is concluded that CBF and CMRO2 are disproportionally decreased during septic encephalopathy in association with dysfunction of the CNS and decreased electrical activity.
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PMID:Cerebral circulation and metabolism in patients with septic encephalopathy. 199 41

The purpose of the present investigation was to study changes in cerebral blood flow (CBF) in hepatic encephalopathy, to ascertain whether this was related to the changes in liver function and whether these changes gave any prognostic information. CBF, determined by the intravenous xenon-133 method, and liver functions, assessed by the prothrombin index, bilirubin concentration, and the galactose elimination capacity, were studied in patients with acute fulminant liver failure and in patients with encephalopathy due to chronic liver diseases--that is, cirrhosis of various etiologies. The CBF range in healthy young subjects (age, 23-42 years) was 44-61 ml/100 g/min; in patients with grade I + II encephalopathy (mean +/- SEM) it was 32.8 +/- 3.6 ml/100 g/min in acute (n = 4; age, 28 +/- 8 years) and 37.0 +/- 3.3 ml/100 g/min in chronic liver patients (n = 10; age, 51 +/- 2 years). In grade III + IV encephalopathy it was 28.7 +/- 3.8 ml/100 g/min in acute (n = 8; age, 28 +/- 3 years) and 32.9 +/- 3.7 ml/100 g/min in chronic patients (n = 12; age, 49 +/- 3 years). CBF did not correlate with the liver function and was of no prognostic value. The liver function was markedly reduced in all the patients, without any differences between patients with acute or chronic liver diseases or the different degrees of hepatic encephalopathy. In conclusion, a marked reduction of the CBF was seen in hepatic encephalopathy, irrespective of the etiology of the disease.
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PMID:Cerebral blood flow and liver function in patients with encephalopathy due to acute and chronic liver diseases. 273 87

Selenium deficiency has been implicated as contributing to hepatic injury in alcoholics. The mechanism by which this occurs is most likely lipoperoxidation secondary to decreased activity of the selenoenzyme glutathione peroxidase. To further assess this relationship, we measured selenium content in autopsy livers in 12 patients with alcoholic cirrhosis compared to 13 patients matched for age and sex dying from other causes, mostly with cardiopulmonary diseases. The mean (+/- SEM) hepatic selenium content in cirrhosis was 0.731 +/- 0.077 microgram/g dry weight versus 1.309 +/- 0.166 microgram/g in controls (P less than 0.005; Student's t test). Clinical and biochemical indices of significant hepatic dysfunction, including encephalopathy, ascites, and elevations of serum bilirubin or prothrombin time, were only present in the cirrhotic group. A significant inverse correlation between hepatic selenium content and the prothrombin time was noted (r = -0.50; P less than 0.02). No significant relationships between hepatic selenium and the abnormalities of bilirubin, albumin, or aspartate aminotransferase were found. We conclude that significantly decreased hepatic selenium stores are present in patients with severe alcoholic cirrhosis compared to controls. The magnitude of that selenium deficit does correlate with some indices of hepatic function, specifically the prothrombin time. These data lend further support to a true selenium deficiency state in alcoholic cirrhosis. It is highly possible that selenium deficiency represents an important link, synergistically joining the nutritional and hepatotoxic backgrounds of alcoholic liver injury and cirrhosis.
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PMID:Decreased hepatic selenium content in alcoholic cirrhosis. 316 92

Serum levels of the potent inhibitory neurotransmitter gamma aminobutyric acid (GABA) were measured in 10 patients with chronic liver disease and hepatic encephalopathy, 11 patients with chronic liver disease and no evidence of hepatic encephalopathy, 7 patients with end-stage renal disease and 11 healthy volunteers. Serum GABA levels were elevated in all 10 patients with hepatic encephalopathy, 5/11 with liver disease and no encephalopathy and 4/7 renal disease patients. The mean serum GABA level for the encephalopathic patients (0.92 +/- 0.13 microM, mean +/- SEM) was significantly greater than the mean for liver disease patients without encephalopathy (0.48 +/- 0.05 microM, p less than 0.05), renal disease patients (0.46 +/- 0.04 microM, p less than 0.05) and healthy volunteers (0.39 +/- 0.03 microM, p less than 0.001). These results would tend to support the hypothesis that GABA may play a role in the pathogenesis of hepatic encephalopathy.
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PMID:Serum gamma-aminobutyric acid (GABA) levels in patients with hepatic encephalopathy. 405 11

Patients undergoing dialysis may accumulate tissue aluminum burdens, and are at risk of developing two aluminum-associated syndromes, namely dialysis osteomalacia and encephalopathy. We address the clinical usefulness of serum aluminum levels in the diagnosis of dialysis osteomalacia. Twenty-four patients, 15 with dialysis osteomalacia and nine with clinically apparent secondary hyperparathyroidism, had serum aluminum levels measured before and after a standard infusion of a chelating agent, deferoxamine (DFO). Baseline serum aluminum levels were regarded as "high" (greater than 133 micrograms/L) if they exceeded 1 SD above the mean (74 micrograms/L) for a larger population of 152 patients undergoing routine hemodialysis. All patients had a bone biopsy for assessment of aluminum deposits by a specific histochemical stain. High serum aluminum levels had a diagnostic sensitivity of 60% in predicting those patients ultimately shown to have dialysis osteomalacia associated with histochemical evidence of aluminum accumulation in bone biopsy specimens; however, 40% of patients with histologic evidence of dialysis osteomalacia would have been missed if only serum aluminum had been used as a diagnostic test. Serum aluminum levels (+/- SEM) were 194 +/- 31 micrograms/L in patients with dialysis osteomalacia and 120 +/- 42 micrograms/L in those with secondary hyperparathyroidism (P greater than 0.05). Serum aluminum levels rose in all patients after DFO infusion to peak levels of 664 +/- 110 and 514 +/- 90 micrograms/L in patients with osteomalacia and hyperparathyroidism, respectively. However, neither the peak serum aluminum level nor its increment after DFO infusion distinguished between patients with osteomalacia and secondary hyperparathyroidism more effectively than did the baseline serum aluminum level.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Do serum aluminum levels reflect underlying skeletal aluminum accumulation and bone histology before or after chelation by deferoxamine? 406 79

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


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