1/9. Highly heterogeneous nature of delta-aminolevulinate dehydratase (ALAD) deficiencies in ALAD porphyria.The properties of 9 delta-aminolevulinate dehydratase (ALAD) mutants from patients with ALAD porphyria (ADP) were examined by bacterial expression of their complementary DNAs and by enzymologic and immunologic assays. ALADs were expressed as glutathione-S-transferase (GST) fusion proteins in escherichia coli and purified by glutathione-affinity column chromatography. The GST-ALAD fusion proteins were recognized by anti-ALAD antibodies and were enzymatically active as ALAD. The enzymatic activities of 3 ALAD mutants, K59N, A274T, and V153M, were 69.9%, 19.3%, and 41.0% of that of the wild-type ALAD, respectively, whereas 6 mutants, G133R, K59N/G133R, F12L, R240W, V275M, and delTC, showed little activity (< 8%). These variations generally reflect the phenotype of ALAD in vivo in patients with ADP and indicate that GST-ALAD fusion protein is indeed useful for predicting of the phenotype of ALAD mutants. The location of F12L mutation in the enzyme's molecular structure indicates that its disturbance of the quaternary contact of the ALAD dimer appears to have a significant influence on the enzymatic activity. Mouse monoclonal antibodies to human ALAD were developed that specifically recognized a carboxy terminal portion of ALAD, or other regions in the enzyme. This study represents the first complete analysis of 9 mutants of ALAD identified in ADP and indicates the highly heterogeneous nature of mutations in this disorder.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
2/9. Cytofluorometry as a diagnosis of protoporphyria.Protoporphyria is a disorder that usually has cutaneous symptoms. Only in a few cases liver disease develops, invariably progressing to cirrhosis and liver failure. A case of a patient who suffered from photosensitivity as a result of protoporphyria since the age of 2 is described. At age 33, she first presented with cholestatic hepatitis. At age 40, liver failure developed requiring liver transplantation. Quantitative cytofluorometry proved to be a quick and simple method in the follow-up of her erythrocyte protoporphyrin levels before, during, and after transplantation. fluorescence correlated well with the protoporphyrin levels obtained by high-performance liquid chromatography (r = 0.98), a comparably cumbersome and complicated method for the determination of protoporphyrin. In addition, single cell analysis enabled us to follow the effects of transfusion therapy on protoporphyrin levels of the patient's own erythrocytes, which has not been possible by previous methods. Thus, cytofluorometry might prove to be elegant and useful for screening and future studies on therapy and pathophysiology of protoporphyria.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
3/9. Familial symptomatic porphyria in south africa.Seven members from 3 generations of a family investigated for evidence of symptomatic porphyria (SP) were found to be affected in varying degrees by the disease. Four had cutaneous lesions, while all 7 had biochemical abnormalities diagnostic for SP in their excreta, plasma or hepatic tissue. The results were obtained using the highly sensitive technique of quantitative fluoroscanning after separation of the porphyrin methyl esters by thin-layer chromatography. This clear case of familial SP is rare in south africa where the high incidence of the sporadic form of the disease is well documented. This study indicates that SP occurs in the following two forms: (i) the sporadic type, usually found as an uncommon associate of chronic liver disease; and (ii) the rare familial type, inherited as an autosomal dominant trait.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
4/9. porphyria cutanea tarda and chronic renal failure.Bullous dermatosis developed in a patient with renal failure who was on hemodialysis. The results of standard tests for porphyria cutanea tarda--quantitation of urinary and fecal porphyrins by fluorometric assay--were within normal limits or were nondiagnostic. Assay of plasma using high-pressure liquid chromatography, however, revealed that this patient had a porphyrin profile consistent with porphyria cutanea tarda. A porphyria-like bullous eruption may occur in patients with chronic renal failure; however, in only a few cases have laboratory studies confirmed the diagnosis of porphyria cutanea tarda. Our experience suggests that, in patients with renal failure, a plasma assay may be more reliable than tests of the urine and feces in establishing a diagnosis in those patients who actually have disorders of porphyrin metabolism. We also report the results of assay of erythrocyte uroporphyrinogen decarboxylase activity and fecal isocoproporphyrin.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
5/9. Pseudoporphyria associated with consumption of brewers' yeast.A case of pseudoporphyria associated with excessive consumption of brewers ' yeast was studied. Detailed analysis of the yeast tablets by high performance liquid chromatography showed the presence of dicarboxylic deuteroporphyrin , mesoporphyrin, and protoporphyrin; coproporphyrin I and III isomers; and uroporphyrin I and III isomers. The faecal porphyrin concentration of the patient taking yeast tablets was significantly increased, resembling the excretion pattern in variegate porphyria. Any patient showing an unusual porphyrin excretion pattern on high performance liquid chromatography should be investigated for a possible dietary cause.- - - - - - - - - - ranking = 2keywords = chromatography (Clic here for more details about this article) |
6/9. Erythropoietic protoporphyria showing solar purpura.An 11-year-old girl with erythropoietic protoporphyria is described. She was admitted to our hospital complaining of swelling and purpura on her arms resulting from overexposure to solar radiation. An elevated level of protoporphyrin in the red blood cells and feces was detected by thin-layer chromatography and fluorescent scanning analysis.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
7/9. Delayed onset of overt porphyria cutanea tarda in a patient on long-term haemodialysis. A case report.After 7 years on haemodialysis, a 37-year-old anephric man developed cutaneous lesions of the hands, arms and face, shown by skin biopsy to be compatible with porphyria cutanea tarda (PCT) (symptomatic porphyria). Elevated levels of plasma uroporphyrin and 7-COOH porphyrin were detected alongside a predominant isocoproporphyrin fraction in the faeces by means of quantitative thin-layer chromatography, confirming the diagnosis of overt PCT. The plasma uroporphyrin did not pass into the dialysate, even after chloroquine therapy. There was no evidence of hereditary PCT, chronic liver disease or iron overload, although the patient had a history of excessive alcohol consumption. The overt PCT developed after 8 months of home dialysis using softened water with high aluminium concentrations and subsided clinically and biochemically when the softened water was replaced by deionized water.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
8/9. The first Swedish case of congenital erythropoietic porphyria, with a revised view of the porphyrin excretion pattern in this disease.A case of congenital erythropoietic porphyria (CEP) in a Swedish boy is described. It is the second case of this extremely rare disease encountered in scandinavia. Like the first Scandinavian case--a Norwegian boy--this patient showed a porphyrin excretion pattern like that of porphyria cutanea tarda (PCT) which was regarded as pointing to a hepatic type of porphyria. In the Norwegian boy this was regarded as atypical, but our study of the literature revealed two older cases with features pointing to a similar pattern and disclosed that analysis of the porphyrin pattern with modern methods, such as thin-layer chromatography, has not been performed in the great majority of the cases of CEP, because such methods were not available at the time these cases were published. Therefore, it is necessary to study more cases of CEP with modern analytical methods in order to get an adequate picture of the porphyrin pattern typical of this disease.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
9/9. Thin layer chromatography and fluorescent scanning analysis of porphyrins.A combined technique of two dimensional thin layer chromatography with fluorescent scanning was applied to the estimation of urinary porphyrins in 2 patients with porphyria cutanea tarda. Porphyrin patterns were also examined with the technique on urine, liver and skin samples obtained from a hexachlorobenzene-induced porphyric rat. Results obtained showed that uroporphyrin and hepta-carboxylic porphyrin were predominant in the urine, liver and skin.- - - - - - - - - - ranking = 5keywords = chromatography (Clic here for more details about this article) |