PubMed Health⌕ Search

Biomedical subjects

E Roth

Publications and source records attributed to E Roth.

At least 163 records · Page 9Linked to original sources

Influence of leupeptin on protein and amino-acid metabolism in septic rats.

We investigated the influence of leupeptin (LP) intraperitoneal injection (40 mumol/2 days) on protein and amino-acid metabolism of septic rats (cecal ligation). All septic rats lost weight (-17 +/- 4 g), which was not prevented by LP administration (-24 +/- 1.8 g, n.s.). LP injection evoked weight loss even in normal rats (p less than 0.05 vs controls). Weight loss was accompanied by enhanced urinary nitrogen losses in all three groups. LP reduced food intake for 47% in control rats. Cecal ligation, and also the administration of LP, led to alterations of amino-acid metabolism. The most important changes were found in muscle free amino-acid concentrations with highly decreased levels of free glutamine. A glutamine deficiency is known to be related to a decreased rate of protein synthesis. The proteolytic rate in incubated soleus muscle was increased for 11.5% and even higher in LP-treated septic rats (+22%). It is concluded that the administration of LP cannot reverse protein catabolism in sepsis--possibly because LP does not influence those enzymes or proteases involved in tissue loss, or LP is inactivated by enzymes in rat tissues.

Amino Acids↗

Effect of intracellular folate concentration on the modulation of 5-fluorouracil cytotoxicity by the elevation of phosphoribosylpyrophosphate in cultured human KB cells.

The effects of extracellular folate concentration on intracellular folate and phosphoribosylpyrophosphate (PRPP) levels and the cytotoxicity of methotrexate and 5-fluorouracil were studied in human KB cells grown in fetal bovine serum-supplemented Eagle's minimum essential medium, which contained standard high folic acid levels (2.3 microM) (standard or S medium), or folic acid-free serum-supplemented medium containing approximately 4 nM 5-methyltetrahydrofolate (physiological or P medium), a folate level and form more comparable to that in normal human serum. Macrocytosis and prolongation of the doubling time by 150% were observed after 5-10 serial passes in P medium, but after 10-15 serial passes, KB cells became "adapted" to P medium with return of size and doubling time to values indistinguishable from cells maintained in S medium. Cellular folate levels fell, and marked elevations in PRPP levels from 68 +/- 43 to 642 +/- 287 pmol/mg cell protein (mean +/- SD) were observed as KB cells were serially passed through P medium. Human leukemia HL-60 and K562 cells and MJY-alpha mouse mammary tumor cells serially passed in P medium also exhibited 10- to 20-fold elevations in PRPP levels. Glucose consumption, glucose decarboxylation, thymidine and adenosine specific uptake, thymidine incorporation into DNA, and 5-fluorouracil uptake were studied in KB cells with elevated and control PRPP levels. As determined by clonal assay, despite elevated PRPP levels, KB cells cultured in P medium were less sensitive to 5-fluorouracil than cells cultured in S medium unless exogenous folate was added. These data support the concept that endogenous folate levels may be inadequate for optimal 5-FU pharmacological action in KB cells with a modulated increase in PRPP levels.

Adenosine↗

Microtiter assay for acetylcholinesterase.

A microtiter plate adaptation of the classical Ellman colorimetric procedure for measurement of acetylcholinesterase activity is described. This method permits use of an enzyme-linked immunosorbent assay plate reader for rapid analysis of multiple samples and is particularly suitable for analysis of acetylcholinesterase activity on sucrose gradients. The novel procedure is rapid and sensitive and does not require use of radioactive material.

Acetylcholinesterase↗

Free amino acid levels in muscle and liver of a patient with glucagonoma syndrome.

This study set out to measure the amino acid concentrations in the femoral artery, femoral vein, hepatic vein, muscular and hepatic tissue, and urine of a patient with the glucagonoma syndrome. The total plasma amino acid concentration was severely reduced on admission (737 mumol/L, 26% of normal), with only a slight increase during intravenous administration of 200 g of amino acids per day. The total intracellular amino acid levels in the muscle were 86%, and those of the liver were 47% of the normal range. Only 0.62% of the amino acids administered were found in the urine. Arteriovenous amino acid concentration differences across the muscle and splanchnic tissue indicated the release of amino acids (mainly glutamine, glycine, and alanine) from the muscle and the absorption of amino acids by the splanchnic bed. This study shows that the infusion of a high amount of amino acids cannot increase the subnormal plasma AA levels of patients with the glucagonoma syndrome. The low total plasma AA levels are paralleled by decreased intracellular free amino acid levels in the muscle and liver.

Adenoma, Islet Cell↗

Phenylalanine: total amino acid ratio in 45 burn patients.

In 45 burn patients serum amino acids together with liver enzymes and other serum parameters were determined. Phe levels, Phe:Tyr and Phe:TAA ratios were correlated with the clinical course of the patient's condition. Based on empirical data, an increase in the Phe:TAA ratio of over 3% was found to be the best indicator of a critical period in the clinical course. An increase in the Phe:TAA ratio above 3% accompanied the signs of sepsis. If the patient recovered, the ratio decreased. Ratios which kept constant or even increased--indicating a possible fatal clinical outcome--were found to be alarming. In our experience Phe levels or Phe:Tyr ratios did not have indicative functions.

Adult↗

[Intracellular amino acid concentrations in various disease states].

The determination of free amino acids (AA) in human tissue is far more complicated than the analysis of plasma AA. The concentrations of free AA are different in plasma, liver and muscle, respectively. Pathological conditions like sepsis, liver failure and glucagonoma syndrome lead to characteristic alterations in the concentrations of free AA. However, the relationship between cytosolic AA concentrations and protein synthesis are not yet clear. Possibly drastically reduced levels of single AA (e.g. glutamine) lead to a 'down'-regulation of protein synthesis.

Amino Acids↗

[Measuring blood flow and catheterization technic in the acute and chronic dog model].

Metabolic studies under in vivo conditions may require a simultaneous catheterization of various organs. Because of phylogenetic relationships, pigs or dogs are best suitable for metabolic investigations. Organ-specific flow rates and substrate balances can be determined by means of dye dilution techniques (indocyanine green - ICG, para-aminohippuric acid - PAH, bromsulphthalein - BSP). An easy method for catheter insertion under anesthesiological and operative conditions is described.

Animals↗

[Measuring cyclosporin in immunosuppressive treatment following liver and heart transplantation].

Selective suppression of the immune system in graft recipients is now achieved in most cases by treatment with cyclosporine A. Due to large individual differences in absorption, utilization and metabolisation of this drug, therapeutic blood levels (immunosuppression/toxicity) can be maintained only by frequent measurements of the cyclosporine concentrations in blood samples and dosage readjustments. In the present study, we measured cyclosporine in whole blood samples from 37 patients (23 liver and 14 heart transplant recipients) using an high pressure liquid chromatographic method for native cyclosporine A which has been developed in our laboratory and a radioimmunoassay method (cyclosporine A + metabolites). By comparison of the results of HPLC and RIA-measurements (n = 520) we found a relatively stable metabolization rate (RIA/HPLC-ratio) of 4.23 +/- 1.30 for heart transplant recipients. In contrast RIA/HPLC ratios were highly variable in liver graft recipients ranging from 1.3-9 for the same patient in the posttransplant period. The liver recipients could be classified into two groups according to their mean RIA/HPLC-ratios: for 11 patients we observed a mean ratio of 2.65 +/- 0.35, for another 12 patients one of 4.35 +/- 0.75. Lower metabolisation rates seem to be associated with low donor age. No direct correlation was found between changes in RIA/HPLC-ratios and liver function, rejection and infection periods. Rejection treatment with high doses of methylprednisolone had no systematic influence on cyclosporine metabolisation in our patients. Since cyclosporine metabolites, at least those ones which are most abundant, have less immunosuppressive and toxic effects we recommend measurements of cyclosporine blood concentrations with any HPLC-method specific for the unchanged drug.(ABSTRACT TRUNCATED AT 250 WORDS)

Chromatography, High Pressure Liquid↗

Assessment of closed head injury in trauma-related spinal cord injury.

The complete medical records of 122 patients who sustained traumatic spinal cord injuries were reviewed to determine the frequency and results of emergency room assessments for loss of consciousness (LOC) and post-traumatic amnesia (PTA). Eighty-eight percent of the patients were assessed for LOC and 19% were assessed for PTA. Fifty patients (41% of the total population) admitted to LOC, PTA or both. Fourteen of these 50 patients underwent subsequent radiographic examinations of the skull, all of which were negative. Because of the association of intracranial complications and long-term cognitive sequelae with even brief LOC or PTA, early recognition of craniocerebral trauma is an important component of the acute management of spinal cord injured patients.

Adolescent↗

Metabolic changes of patients with acute necrotizing pancreatitis.

We carried out metabolic investigations of 26 patients with severe forms of acute pancreatitis which were evaluated by an organ score. We formed six groups from this data: survivors and deceased in the first week, the second week, and after a further two weeks of illness. The amino acid patterns in plasma and muscles deviated considerably from normal at all times in both the surviving and the deceased patients. In particular, changes in the concentrations of branched-chain amino acids and glutamine in the muscle tissue have a prognostic value. In the range two to four (normal range: above 20), the factor glutamine/VAL+LEU+ILE characterizes a prefinal condition in non-survivors. This factor increased in patients recovering from the illness from 6 to values over 20. Non-survivors (NS) had higher plasma levels of glucose and glucagon compared to surviving patients. Plasma glucagon concentrations in NS reached levels up to 4,000 pg/mL at admission, which declined gradually to normal range during the course of the illness.

Acute Disease↗

[Acute renal failure in abdominal infection. Comparison of hemodialysis and continuous arteriovenous hemofiltration].

58 patients with peritonitis and acute renal failure (ARF) were treated either by haemodialysis (HD, n = 22), continuous arteriovenous haemofiltration (CAVH, n = 9), or continuous pump-driven haemofiltration (CPDHF, n = 27). In contrast to HD, which led to severe hypotension in 31.9% of procedures and to cardiac arrest in 3 cases, CPDHF caused neither haemodynamic nor metabolic alterations. Control of uraemia was most effective in the CPDHF group, too. Mean daily BUN and creatinine values fell significantly (p less than 0.005) and remained at 60 mg % and 2.0 mg %, respectively, whereas during HD no significant changes were found. During CAVH serum creatinine showed an insignificant decline, whereas BUN even increased. Despite higher costs CPDHF seems to be a promising alternative to HD or CAVH for treatment of ARF in septic patients, as mortality was lower in the CPDHF group and recovery of renal function occurred in 48.2%, whereas during HD only 27.3% recovered from ARF.

Acute Kidney Injury↗

[Hemodynamics and coronary dynamics under ISDN long-term therapy].

Although nitrates are among the oldest drugs in cardiology the problem of tolerance is a scientific challenge of today. We examined and compared the effects of initial and chronic therapy (4 weeks) with 1 X 1 ISDN 120 mg sustained release in 9 patients with coronary heart disease and impaired left ventricular function. At intraindividually identical workloads (average 50 +/- 12 watt) there was a reduction of PCWPm from 32.5 +/- 9.5 to 19.7 +/- 9.8 mm Hg. This reduction of PCWPm during bicycle ergometry was fully achieved in long-term therapy. With the first dose of ISDN cardiac index (CI) at maximum workload increased from 6.0 +/- 1.2 to 6.8 +/- 1.3 l/min/m2; during chronic therapy cardiac index improved from 5.3 +/- 1.3 to 6.6 +/- 1.1 l/min/m2. Exercise capacity during bicycle ergometry in the sitting position increased concomitantly from 414 to 686 watt X min. In long-term therapy there was a further significant improvement to 772 watt X min. ST-segment depression, measured as sum of ST-depression in all 12 standard ECG leads decreased from 0.63 mV before medication to 0.11 mV after the first dose and to 0.16 mV in long-term therapy. The investigation of ventricular function during ventriculography and the investigation of coronary vasomotion during coronary angiography after ergonovine maleate i.v. and ISDN s.l. also demonstrated the full nitrate effect in long-term therapy.

Adult↗

[Regional results of human liver transplantation in Vienna].

21 cases of transplantation of the liver are analysed for indication, anaesthesia, operative management, anhepatic period, immunological therapy and specific post-operative problems (jaundice and rejection episodes). Causes of death are noted and prediction of survival gives a rate of 55%/1st year in the 17 patients operated on since 1982 under a standardised management schedule. The transplantation programme in Vienna provides routine treatment for otherwise untreatable primary (57% cases) and secondary metastatic (14%) tumours of the liver, and, in the second place, for end-stage hepatic cirrhosis (14%) and certain rare liver diseases (14%).

Adult↗