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1.
  • 1.1. In the last decade specific enzyme deficiencies have been reported in five out of the six known varieties of human porphyrias.
  • 2.2. These deficiences concern uroporphyrinogen III-consynthetase in erythropoietic porphyria; uroporphyrinogen I-synthetase in acute intermittent porphyria; uroporphyrinogen decarboxylase in porphyria cutanea tarda; coproporphyrinogen oxidase in heredity coporphyria and ferrochelatase in protoporphyria.
  • 3.3. These enzyme deficiences explain the specific troubles in prophyrin metabolism in these diseases and hence the main clinical and biochemical manifestations.
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2.
  • 1.1. Exposure to dioxin triggered a clinically manifest chronic hepatic porphyria (porphyria cutanea tarda) in two patients (brother and sister) with hereditary uroporphyrinogen decarboxylase deficiency.
  • 2.2. The patients showed a decrease of erythrocyte uroporphyrinogen decarboxylase activity to ~ 50% of controls even in reinvestigations after three years, whereas clinical symptoms and porphyrinuria had improved considerably. Only a subclinical phase of chronic hepatic porphyria persisted. Subnormal uroporphyrinogen decarboxylase activity could be determined in altogether nine family members.
  • 3.3. The remission of porphyria cutanea tarda into a subclinical phase occurred after chloroquine therapy. Subclinical phases of chronic hepatic porphyria (type A) in other family members remitted without special therapy.
  • 4.4. Among the 60 persons dioxin-exposed by the Seveso accident, a secondary coproporphyrinuria was found in 22% of examined patients with transition to a subclinical chronic hepatic porphyria in 5 cases. The changes had subsided completely after one year. A persistence of the transition state in 3 cases is probably due to alcohol influence. None of these cases developed a porphyria cutanea tarda.
  • 5.5. The investigations showed that a hereditary disposition is necessary for biochemical and clinical expression of chronic hepatic porphyria after a unique dioxin exposure. This is not given in the sporadic cases: after a unique dioxin exposure they indeed develop a symptomatic disturbance of porphyrin metabolism but not a clinically relevant chronic hepatic porphyria.
  • 6.6. We conclude that a unique acute exposure to dioxin can trigger the chronic hepatic porphyria disease process in persons with an underlying genetic abnormality of uroporphyrinogen decarboxylase.
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3.
  • 1.1. Changes in the hemoglobins present in many vertebrates have been observed during development and during anemic episodes.
  • 2.2. A change in the number of hemoglobins present and their relative amounts was observed when adult Triturus cristalus newts were made anemic by injection of acetylphenylhydrazine.
  • 3.3. Hemoglobin IV, which is a minor hemoglobin in healthy adults, was found to be a major component during the subsequent erythropoietic response to hemolytic anemia.
  • 4.4. No new hemoglobin not already present in the non-anemic state was detected during the response to induced anemia.
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4.
On the basis of metabolite and enzyme studies a new type of acute hepatic porphyria with porphobilinogen synthase defect and repeated intermittent acute manifestations, abdominal colics, tachycardia and hypertension, and a persistent neurological syndrome was found in two young male patients. The main characteristic features are the following:
  • 1.1. High urinary δ-aminolevulinic acid excretion( ⪢ 1 mmol/24hr), slight increase of porphobilinogen (up to 25 μmol/24 hr) and high increase of porphyrins (up to 22 μmol/24 hr) with coproporphyrin dominance.
  • 2.2. Normal fecal and liver porphyrins.
  • 3.3. Slight increase of erythrocyte protoporphyrin.
  • 4.4. Decrease of porphobilinogen synthase activity in erythrocytes in both cases below 1% of healthy and not lead-exposed persons; normal activities of uroporphyrinogen synthase and decarboxylase in erythrocytes.
  • 5.5. Low-normal lead concentrations in blood and low-normal lead excretion in urine in both cases; normal lead content in bone.
  • 6.6. Normal plasma and urinary amino acids.
  • 7.7. Irrelevant hepatological (liver biopsy), general clinical chemical and hematological findings.
  • 8.8. Diminished activity of porphobilinogen synthase in nearly all family members of both patients. From these investigations it can be concluded that there is no exogeneous, “toxic” cause of this porphyria. Porphobilinogen synthase in lead poisoning is not diminished to such an extent as demonstrated here; in contrast to lead intoxication, porphobilinogen synthase activity cannot be activated or reactivated by thiols. All clinical and pathobiochemical data point at a new enzymatic type of endogeneous acute hepatic porphyria with intermittent acute manifestations, clinically analogous to so-called acute intermittent porphyria. Porphyrin precursors and porphyrin excretion both reflects the enzymatic defect and the regulatory consequences starting with the induction of δ-aminolevulinic acid synthase.
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5.
  • 1.1. There is no uniform pattern of porphyrin synthesis by whole blood and haemolysates, between the different mammalian species studied.
  • 2.2. Coproporphyrin, is the dominant porphyrin synthesised by intact red cells.
  • 3.3. Uroporphyrin synthesis increases significantly in the majority of species when the cells are haemolysed.
  • 4.4. In the mouse large amounts of protoporphyrin are synthesised by intact red cells which increases further on haemolysis.
  • 5.5. The low porphyrin synthesising capacity of cow and sheep red cells is not due to any rate-limiting activity of the enzyme ALA-dehydratase.
  • 6.6. The dog has a pattern of porphyrin synthesis and excretion similar to that found in the rabbit, and the possibility exists, that a similar energy-dependent carrier mechanism for movement of uroporphyrin and coproporphyrin across red cell membranes found in the rabbit may be present in this species.
  • 7.7. The findings may be of significance in the interpretation of porphyrin excretion patterns in experimental porphyria.
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6.
  • 1.1. The porphyrins in bullous fluids from two female patients, one with variegate porphyria (VP) and the other with congenital erythropoietic porphyria (CEP), have been analyzed and in each case found to contain an unusual porphyrin, a 4-COOH porphyrin resembling isocoproporphyrin in the VP patient. In the patient with CEP the blister fluid was shown to contain a porphyrin with a Chromatographie mobility compatible with that of isocoproporphyrin.
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7.
  • 1.1. When protoporphyrin is added to normal red cells it distributes to about 30% in the stroma and 70% in the cytosol. By comparison, in erythropoietic protoporphyria red cell protoporphyrin is found to more than 95% in the cytosol.
  • 2.2. At equimolar concentrations of protoporphyrin the photohemolysis is much more severe in normal red cells with exogenous protoporphyrin than in red cells from patients with erythropoietic protoporphyria.
  • 3.3. The photohemolysis is markedly enhanced when D2O is used as solvent instead of H2O.
  • 4.4. The results suggest that the photodamage is determined by the ability of susceptible structures to accumulate porphyrins, the partition of porphyrins between lipophilic and hydrophilic structures and the longevity of singlet oxygen in lipophilic environments.
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8.
  • 1.1. Seasonal changes of circulating blood parameters of Natrix n. natrix were evident and involved both sexes to the same extent.
  • 2.2. A significant decrease in red cell count, haematocrit and haemaglobin concentration in the mating period, and an increase in those parameters and mean cell volume in autumn were observed, and haemodilution during winter torpor.
  • 3.3. The changes during the breeding season had probably a hormonal background; in winter, they resulted first of all from a decreased erythropoietic activity and, to a lesser extent, from an increased red blood cell breakdown rate. However, the possibility that some erythrocytes were withdrawn from the circulation cannot be excluded.
  • 4.4. Winter lymphocytopenia, eosinocytopenia and neutrophilic granulocytosis in females during egg laying were expressions of changes of leucocyte formula.
  • 5.5. Seasonal cyclicity was found only with respect to the white cell count in males and the eosinophile fraction in males and females.
  • 6.6. Probable reasons for, and mechanisms of the changes in blood composition are discussed.
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9.
  • 1.1. The incidence of porphyria cutanea tarda (PCT) has increased considerably in Denmark during the last decade (Table 1) but is much higher in Czechoslovakia than in Denmark.
  • 2.2. We therefore made a detailed study of the urinary porphyrin excretion pattern in 10 cases of PCT from Copenhagen and 10 from Prague.
  • 3.3. The results are presented (Table 2). They show no simple pattern.
  • 4.4. Comparison with the type subdivision of Doss et al. (Table 3) and the important findings of Piñol Aguade et al. show that such elaborate type division, involving considerable and time-consuming analytical work, belong to research and have limited value in clinical work.
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10.
  • 1. The haemoglobin of the South American lungfishLepidosiren paradoxa has a single component.
  • 2. The equilibria of this respiratory protein with oxygen have been investigated both in the blood and with the purified haemoglobin. There is a substantial, normal, alkaline Bohr effect and marked sensitivity to organic phosphates in the haemoglobin solutions.
  • 3. Studies on the pH dependence of the kinetics of oxygen dissociation can be interpreted in terms of a normal Bohr effect.
  • 4. The kinetics of combination of carbon monoxide have an unusual pH dependence.
  • 5. These findings are discussed in terms of the two-state model of Monodet al. (1965)
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11.
  • 1.1. Aortic xylosyl-transferase has been purified by isoelectric focusing.
  • 2.2. It appears as a single molecular species.
  • 3.3. It catalyses xylose transfer on an exogenous polypeptide acceptor. poly-l-serine.
  • 4.4. Optimal activity of the enzyme is pH 7.2. and a temperature of 57°C.
  • 5.5. The phenomenological study of this enzyme involving 2 substrates and 2 products are in agreement with ordered Bi-Bi mechanism.
  • 6.6. Possible relations with Theorell-Chance mechanism are discussed.
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12.
  • 1.1. A variety of haematological parameters were determined in adult Dasyurus viverrinus.
  • 2.2. Haemoglobin and red cell counts were high with a very low mean cell volume.
  • 3.3. Basophils are absent but the eosinophils contain small numbers of basophilic granules which may indicate a dual role for this cell.
  • 4.4. “Ring Form” leucocytes are present.
  • 5.5. Three types of red cell picture could be identified, some animals showing large numbers of spherocytes, spicule cells, and inclusion bodies.
  • 6.6. These cells resemble those found in some inherited human haemolytic anaemias but there was no evidence of haemolysis in the animals.
  • 7.7. An alkali resistant haemoglobin component is present.
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13.
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14.
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17.
  • 1.1. Galactose oxidase is known to catalyze the oxidation of the C-6 hydroxymethyl group of galactose to an aldehyde group.
  • 2.2. When the products of a galactose oxidase-catalase treatment of raffinose were examined by gel filtration and ion exchange chromatography, we found that in addition to the expected 6'-aldehydoraffinose, two other components were present.
  • 3.3. One component was neutral and had an elution volume close to that of maltopentaose and on treatment with sodium borohydride or hypoiodite, this component was converted to raffinose or 6'-carboxyraffinose, respectively.
  • 4.4. Fast atom bombardment mass spectroscopy in the negative mode indicated that the major molecular ion had an M/Z of 1003.
  • 5.5. These data are consistent with this component being a dimer of 6'-aldehydoraffmose.
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18.
  • 1.1. The α-amylase activity in the serum of the African elephant has been measured by 2 different methods. Consistently high values were obtained, about 10 times those of normal human serum measured by the same methods.
  • 2.2. Electrophoretic separation of amylase isoenzymes revealed a single band in the γ-globulin region and a group of 4 bands in the β-globulin region.
  • 3.3. Both sets of findings are discussed in relation to results reported on other mammals.
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19.
  • 1.1. A quick and simple procedure is described for purifying kallikrein from human whole saliva. The enzyme has been purified about 2700-fold with a yield of approx. 30%.
  • 2.2. The procedure is based on the immediate fractionation of saliva by ion exchange chromatography. This is followed by a combination of affinity and high performance liquid chromatography.
  • 3.3. The results indicate that another protein component binds to the enzyme at pH 8.0.
  • 4.4. The homogeneity of the enzyme has been demonstrated by gel electrophoresis in the absence as well as in the presence of sodium dodecylsulfate.
  • 5.5. A mol. wt of 40,100±1800 has been calculated from gel electrophores is experiments.
  • 6.6. Sedimentation equilibrium in an analytical ultracentrifuge gave a mol. wt of 39,700.
  • 7.7. The amino acid composition has been determined and it confirms that the enzyme has a low isoelectric point.
  • 8.8. The presence of tryptophan has been demonstrated by absorption and fluorescence spectroscopy.
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20.
  • 1.1. Fundamental chitin digestion characteristics of Crassostrea virginica crystalline style were investigated.
  • 2.2. Optimum temperature and pH were 34°C and 4.8. respectively.
  • 3.3. The colloidal regenerated chitin (0.56mol/0.5 ml: GlcNAc equivalents) was saturating under all enzyme levels encountered.
  • 4.4. There was no evidence of end product inhibition, even after 100 hr incubation.
  • 5.5. Calculated Km for the chitinase complex was 1.19mM when determined using a 30 min assay, but was only 0.70 mM when determined using a 4.6 hr assay.
  • 6.6. Both Km values are lower than reported for similar assays in other molluscs and for most bacteria.
  • 7.7. Effect of substrate preparation on the kinetics are discussed.
  • 8.8. Eight peaks of chitinase activity were resolved by DEAE-Fractogel ion exchange chromatography.
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