Occurrence of CCSVI in patients with MS and its relationship with iron metabolism and varicose veins.

BACKGROUND AND PURPOSE: A new treatable venous disorder, chronic cerebrospinal venous insufficiency (CCSVI), has been proposed in patients with multiple sclerosis (MS). Its relationship with iron metabolism is suggested, but has not been examined prospectively. METHODS: We performed extra- and transcranial echo colour Doppler (ECD) in 90 patients with MS and 41 healthy controls (HC). Indices of iron metabolism and the presence of peripheral signs of impaired venous flow were also examined. RESULTS: The ECD examination showed CCSVI in 8 (9%) of the 90 patients with MS and 0 HC (P = 0.11). The 8 CCSVI-positive MS patients were older (P = 0.02), had less often relapsing-remitting-MS (P = 0.02) and had more neurological disability assessed by expanded disability status scale (EDSS, P = 0.001) and longer duration of disease (P = 0.02) in comparison with the 82 CCSVI-negative MS patients. Multivariate analysis revealed that EDSS remained an independent factor associated with CCSVI (odds ratio 1.89, 95%CI 1.17-3.05, P-value = 0.009). CCSVI MS patients more often had bilateral telangiectasia at the legs (P = 0.008), reticular veins (P = 0.006) and venous stasis dermatitis (P = 0.004). No relationship was found between CCSVI and impaired iron metabolism in patients with MS. CONCLUSIONS: CCSVI is uncommon and is a secondary epiphenomenon in MS and related to more neurological disability and the presence of varicose veins at the legs.

[Metabolic encephalopathy can be a potentially life-threatening complication from valproic acid]. / Metabole encefalopathie als potentieel levensbedreigende complicatie van valproïnezuur.

In two female patients of 62 and 81 years old, a metabolic encephalopathy was diagnosed which was ascribed to the use of valproic acid. Both had elevated ammonia levels in arterial blood, without hepatic failure. The first patient eventually became comatose and required artificial ventilation. After discontinuation of the valproic acid and with the aid of supportive measures, both women recovered. In patients with an impaired level of consciousness who are using valproic acid, a metabolic encephalopathy caused by this drug should be considered. Elevated levels of ammonia can be found but are not mandatory. Discontinuation of valproic acid will lead to recovery of consciousness.

Long-term follow up of a new case of hawkinsinuria.

UNLABELLED: Hawkinsinuria is a rarely diagnosed autosomal dominantly transmitted inborn error of tyrosine metabolism with impaired conversion of 4-hydroxyphenylpyruvate to homogentisate. As a consequence of the defective 4-hydroxyphenylpyruvate dioxigenase activity, large amounts of the unusual, ninhydrin-positive amino acid hawkinsin and later on in life 4-hydroxycyclohexylacetic acid are formed and excreted. Clinically the disease is characterised mainly by chronic metabolic acidosis and severe growth retardation as a result of protein overload. As the ability to form 4-hydroxycyclohexylacetic acid and thereby to cope with the still not very well defined reactive and toxic intermediates increases, clinical symptoms vanish. We report here a new patient with hawkinsinuria having experienced a series of admissions because of unclear hepatopathy, growth retardation, and renal tubular acidosis. CONCLUSION: Prolonged tyrosyluria in the newborn and young baby should cause the clinical chemist not only to exclude tyrosinaemia, galactosaemia, and fructose intolerance but also to look carefully for hawkinsin in the aminoacid chromatogram.

A clinical biochemist's view of the investigation of suspected inherited metabolic disease.

The necessity for a multi-disciplinary approach to the study of genetic disease is discussed. The progress of laboratory investigation programmes made it not feasible and inefficient to run a full metabolic investigation programme in every new patient suspected of inherited metabolic disease. An application form for metabolic investigation is described, which can be used to collect clinical information relevant to metabolic disease. On the basis of the patient's clinical information, selection criteria are given to decide which laboratory investigation programme has to be performed in the individual patient. A full metabolic laboratory investigation programme is described and illustrated with some examples of abnormal metabolite patterns. Diagnostic results over a 2-year period are presented.

A re-evaluation of conditions required for an accurate estimation of the extramitochondrial ATP/ADP ratio in isolated rat-liver mitochondria.

The values reported in the literature for the extramitochondrial ATP/ADP ratio in resting rat-liver mitochondria (State 4) vary widely. The conditions required for an accurate determination of this parameter were therefore investigated. In experiments with rat-liver mitochondria incubated under State-4 conditions, it was found that the extramitochondrial ATP/ADP ratio, as calculated from the values measured in neutralised perchloric acid extracts, was lower than that estimated from the concentrations of creatine and creatine phosphate, using the metabolite indicator method. The discrepancy is due to hydrolysis of ATP occurring in the presence of perchloric acid. Conditions are described for minimising ATP hydrolysis in the presence of perchloric acid, and include the use of low concentrations of perchloric acid, short times of exposure to the acid before neutralisation, low temperatures and the presence of excess EDTA. Under these conditions, the values obtained for the extramitochondrial ATP/ADP ratio agreed with those calculated by the metabolite indicator method, provided ratios do not exceed the value of 100. In cases where the extramitochondrial ATP/ADP does exceed 100, phenol/chloroform/isoamyl alcohol must be used to quench the reactions, as described by Slater et al. (Slater, E.C., Rosing, J. and Mol, A. (1973) Biochim. Biophys. Acta 292, 534-553). With this method, the extramitochondrial ATP/ADP ratio was found to have a value of more than 1000 in rat-liver mitochondria incubated with succinate + rotenone in the resting state (pH 7.0; T = 37 degrees C), in agreement with Slater et al.

The role of Ca2+ and cyclic AMP in the phosphorylation of rat-liver soluble proteins by endogenous protein kinases.

Rat liver soluble proteins were phosphorylated by endogenous protein kinase with [gamma-32P]ATP. Proteins were separated in dodecyl sulphate slab gels and detected with the aid of autoradiography. The relative role of cAMP-dependent, cAMP-independent and Ca2+-activated protein kinases in the phosphorylation of soluble proteins was investigated. Heat-stable inhibitor of cAMP-dependent protein kinase inhibits nearly completed the phosphorylation of seven proteins, including L-type pyruvate kinase. The phosphorylation of eight proteins is not influenced by protein kinase inhibitor. The phosphorylation of six proteins, including phosphorylase, is partially inhibited by protein kinase inhibitor. These results indicate that phosphoproteins of rat liver can be subdivided into three groups: phosphoproteins that are phosphorylated by (a) cAMP-dependent protein kinase or (b) cAMP-independent protein kinase; (c) phosphoproteins in which both cAMP-dependent and cAMP-independent protein kinase play a role in the phosphorylation. The relative phosphorylation rate of substrates for cAMP-dependent protein kinase is about 15-fold the phosphorylation rate of substrates for cAMP-independent protein kinase. The Km for ATP of cAMP-dependent protein kinase and phosphorylase kinase is 8 microM and 38 microM, respectively. Ca2+ in the micromolare range stimulates the phosphorylation of (a) phosphorylase, (b) a protein with molecular weight of 130 000 and (c) a protein with molecular weight of 15 000. The phosphate incorporation into a protein with molecular weight of 115 000 is inhibited by Ca2+. Phosphorylation of phosphorylase and the 15 000-Mr protein in the presence of 100 microM Ca2+ could be completely inhibited by trifluoperazine. It can be concluded that calmodulin is involved in the phosphorylation of at least two soluble proteins. No evidence for Ca2+-stimulated phosphorylation of subunits of glycolytic or gluconeogenic enzymes, including pyruvate kinase, was found. This indicates that it is unlikely that direct phosphorylation by Ca2+-dependent protein kinases is involved in the stimulation of gluconeogenesis by hormones that act through a cAMP-independent, Ca2+-dependent mechanism.