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K H Schulpis

Publications and source records attributed to K H Schulpis.

At least 37 records · Page 2Linked to original sources
PubMed1998

Biotin recycling impairment in phenylketonuric children with seborrheic dermatitis.

OBJECTIVE: To investigate the effect of a therapeutic diet on serum biotin levels and to explain the seborrheic dermatitis in phenylketonuric (PKU) patients on a "loose" diet. DESIGN: Forty-seven patients were divided into two groups: group A (n=21) demonstrated good compliance to a special diet and group B (n=26) were on a "loose" diet. Most of the patients in group B (20/26), who suffered from mild seborrheic dermatitis, were requested to return to phenylalanine (Phe)-restricted diet for at least 15 days. Seventy-nine healthy children of comparable age were used as controls. Biotin serum levels and plasma biotinidase activity were measured in patients as well as controls. In addition, biotinidase activity was evaluated in vitro after incubation with various concentrations of Phe. RESULTS: Biotin levels in group A patients (636+/-118 ng/L) were statistically significantly elevated (P < 0.01) compared with those of group B patients before (412+/-184 ng/L) and after (501+/-160 ng/L) 15 days on a Phe-restricted diet, as well as with those of controls (337+/-290 ng/L). Furthermore, biotinidase activities were decreased in group B patients (4.2+/-1.68 nmol/min/L) compared with those of group A patients (6.4+/-0.7 nmol/min/L) and controls (6.10+/-0.8 nmol/min/L). Additionally, biotinidase activities in the patients of group B were restored to normal (5.78+/-0.81 nmol/min/L), with a simultaneous remission of their skin lesions, after 15 days on a Phe-restricted diet. Moreover, the in vitro findings showed a 51% inhibition of biotinidase activity when incubated with Phe (20 mg/dL). CONCLUSIONS: It is suggested that the high biotin levels in group A patients reflect the intake of water-soluble biotin of vegetable origin. In contrast, the low biotinidase activity in group B patients may be attributed to their high Phe plasma levels, which acts as an enzyme inhibitor, as shown by the in vivo and in vitro results. Consequently, the observed seborrheic dermatitis in PKU children (group B) is associated with an impairment of biotin recycling.

Amidohydrolases↗
PubMed1998

Bone mineral status in children with phenylketonuria under treatment.

Bone mineral status was assessed in 48 children with phenylketonuria (PKU) (20M, 28 F, aged 2.5-17 y). Bone density was measured in the distal third of the right forearm using single photon absorptiometry and was expressed as +/-SD with respect to age- and gender-matched controls. Serum calcium (Ca), magnesium (Mg), phosphorus (P), alkaline phosphatase (ALP), parathyroid hormone and 25-hydroxyvitamin D were measured in morning samples. The ratios of urinary Ca/creatinine (UCa/UCr), UP/UCr, UMg/UCr and hydroxyproline (OH-Pr)/UCr were calculated in urine samples collected over a period of 3 h. Patients' data were compared with those of 50 controls (22 M, 28 F, aged 3-15 y). The data showed severe osteopenia (below -2SD) in 22/48 patients. Bone loss was more prominent in patients over 8 y old. Bone density correlated significantly with age (r=-0.56,p < 0.001) and with Phe (r=-0.49, p < 0.007) but did not correlate with the other biochemical indices studied. Comparing PKU children with controls, significantly higher serum calcium and magnesium (p=0.04, p < 0.001, respectively), lower ALP (p=0.01), higher UCa/UCr ratio (p < 0.001), lower UP/UCr (p < 0.001) and lower UOH-Pr/UCr (p < 0.001) were found. Dietary compliance was poor in patients over the age of 8y, as only 3/22 of < or = 8y had mean serum phenylalanine >10mgdl(-1), in contrast to 21/26 in the older group. It is clear from the data that osteopenia is commonly found in PKU patients from early life. The biochemical data indicate a metabolic state of low bone turnover in PKU patients. In conclusion, a better, more restricted diet may correct osteopenia.

Adolescent↗
PubMed1997

Effects of isotretinoin therapy on lipoprotein (a) serum levels.

BACKGROUND: Increases in plasma concentrations of lipids, triglycerides, and liver enzymes have been reported in patients on isotretinoin therapy. Lipoprotein (a). (Lp (a)), a cholesterol-rich plasma lipoprotein, influences the clotting system and is related to premature coronary heart disease and stroke. METHODS: Blood (7 mL) was obtained from 30 patients with cystic acne before and 30 days after the initiation of oral isotretinoin (0.5 mg/kg/day). RESULTS: An increase in liver enzymes and lipids, except high density lipoprotein, was found in our patients at the end of the study. The mean Lp (a) levels (initial value, 25.91 +/- 3.17 mg/dL) were statistically reduced (p < 0.0001) at the end of treatment (14.80 +/- 2.35 mg/dL). CONCLUSIONS: It is suggested that isotretinoin could be used as an Lp (a) lowering agent in the future.

Acne Vulgaris↗
PubMed1996

Haemostatic variables in phenylketonuric children under dietary treatment.

Classical phenylketonuria (PKU) (McKusick 261600) is an inborn error of metabolism treated by a controlled low-phenylalanine (Phe) diet started as soon as possible in the first days of life. Such a diet can be achieved with vegetable protein and can be considered non-atherogenic because of the reduction of animal products. Thirty patients with PKU were classified into two groups according to their annual mean Phe levels. Their daily protein intake was largely replaced by PKU2 Milupa which contains a mixture of amino acids. The product has no phenylalanine or fat of any kind. Thirty-eight (38) individuals of comparable age were used as controls. Group A (n = 15) had good compliance with the special diet (Phe mean 192 +/- 115 mumol/L); group B (n = 15) did not strictly adhere to the diet (Phe mean 595 +/- 263 mumol/L). Certain haemostatic components (factors I, VII, VIII, and X, antithrombin III, protein C, and plasminogen) and lipid variables (cholesterol, triglycerides, high-density lipoprotein, low-density lipoprotein, very-low-density lipoprotein) as well as Phe levels were estimated. All the haemostatic factors studied were found within the normal range with the exception of a significant reduction in protein C in both groups of PKU patients. Furthermore, a statistically significant reduction in factor VII and X concentrations was observed in patients on strict diet. Cholesterol and low-density lipoprotein concentrations were significantly lower in PKU children compared to normal controls. It is suggested that even though the special diet of PKU children, especially in group A, is rich in vegetables, the reduced fat intake might have impaired the absorption of vitamin K and its delivery to the site of synthesis of vitamin K-dependent haemostatic factors.

Blood Coagulation Factors↗
PubMed1994

Raised beta-endorphin serum levels in children with atopic dermatitis and pruritus.

Atopic dermatitis (AD) is a pruritic cutaneous inflammatory condition. As pruritus and pain are very close symptoms, we determined the beta-endorphin serum concentrations in 21 atopic children with pruritus (group A) and 20 children with healed AD without pruritus (group B). Twenty-five healthy school children were the control group. The beta-endorphin serum concentrations (14.95 +/- 2.75 pmol/l) in group A were statistically (P < 0.001) elevated in our patients compared to controls (8.85 +/- 2.39 pmol/l) whereas these in group B were not elevated (9.4 +/- 2.46 pmol/l). We suggest that the elevated beta-endorphin concentrations in atopic patients with pruritus confirm the hypothesis that there is an increased activity of their opioid system and that an opioid antagonist might block itching which is their major clinical symptom.

Child↗
PubMed1990

Serum carnitine level in phenylketonuric children under dietary control in Greece.

Although total, free and esterified carnitine blood levels were found to be low (p less than 0.001) in phenylketonuric patients under dietary treatment compared to controls, no clinical signs of carnitine deficiency were noticed. Exclusion from the PKU diet of nutrients rich in carnitine has been suggested. Supplementation of the diets with carnitine or preferably enrichment of the PKU formulas with carnitine will rectify the restriction of extrinsic carnitine in PKU dietary treatment.

Carnitine↗
PubMedDate not supplied

The effect of isotretinoin on biotinidase activity.

BACKGROUND: Among the reaction and effects of isotretinoin, mucocutaneous reactions, xerosis and erythema of the skin as well as elevation of liver enzymes and lipids except high density lipoprotein have been reported. OBJECTIVE: Since biotinidase is mainly produced in the liver and partial biotinidase deficiency causes dermatological manifestations, seborrheic dermatitis, alopecia etc., isotretinoin side effects in relation to biotinidase activity were studied. METHODS: Forty-two (n = 42) patients with severe cystic acne had liver function tests, lipid estimations, serum biotin as well as biotinidase activity evaluations before (value 1) and on the 30th day (value 2) of treatment with isotretinoin monotherapy (Roaccutane 0.5 mg/kg/24 h). The same laboratory tests were evaluated in 50 controls only once. Moreover, the effect of isotretinoin on a known plasma biotinidase activity was evaluated after incubation in vitro with various concentrations of the drug. RESULTS: A statistically significant elevation of liver enzymes and lipids, except high density lipoprotein, was observed at the end of this study. On the contrary, biotinidase activity was found to be significantly decreased as compared to the initial values (value 1 = 4.70 +/- 0.89 nmol/min/l, value 2 = 2.50 +/- 0.8 nmol/min/l, p < 0.001) and to controls (5.2 +/- 0.9 nmol/min/l vs. value 2 = 2.50 +/- 0.8 nmol/min/l, p < 0.001). Additionally, biotin levels showed no significant alterations and the in vitro incubation of the enzyme with various concentrations of the drug exhibited no effect on its activity. CONCLUSION: It is suggested that isotretinoin isomers-metabolites act in the liver, resulting in low biotinidase activity.

Acne Vulgaris↗
PubMedDate not supplied

L-phenylalanine effect on rat diaphragm acetylcholinesterase and Na+,K(+)-ATPase.

The effect of different L-phenylalanine (Phe) concentrations (0.24-12.1 mM), on acetylcholinesterase (AChE) and Na+,K(+)-ATPase activities of diaphragm homogenates from 21-day old rats and pure enzymes, was investigated at 37 degrees C. AChE and Na+,K(+)-ATPase activities were determined after preincubation with Phe. AChE activity in diaphragm homogenate or in pure eel E. electricus enzyme showed a decrease, which reached a maximum of 18% with Phe concentrations of 0.9-12.1 mM. However lower Phe concentrations (0.24 mM) increased the enzyme activity (by approximately 22%), only in the diaphragm homogenate. Diaphragm-associated Na+,K(+)-ATPase activity showed a progressive and concentration-dependent decrease, by about 30-35% in the presence of high Phe concentrations. Pure enzyme activity (from porcine cerebral cortex) was not affected by high Phe concentrations (> 0.48 mM), while it was increased by low concentrations. The above results suggest: a) A direct inactivating effect of high Phe concentrations on AChE and an indirect activating effect induced by low concentrations. b) A direct activating effect of low Phe concentrations and an indirect inactivating effect of high ones on Na+,K(+)-ATPase. c) The combination of high Phe concentrations effects on AChE and Na+,K(+)-ATPase could influence the levels of the diaphragm synaptic ACh.

Acetylcholinesterase↗
PubMedDate not supplied

L-phenylalanine effect on rat brain acetylcholinesterase and Na+,K(+)-ATPase.

The effect of different L-phenylalanine (Phe) concentrations (0.1-12.1 mM), on acetylcholinesterase (AChE) and Na+,K(+)-ATPase activities of brain homogenate and pure enzymes, was investigated at 37 degrees C. AChE and Na+,K(+)-ATPase activities were determined according to Ellman G. L., Courtney D., Andres V. and Featherstone R. M. (1961), Biochem. Pharmacol. 7, 88-95 and Bowler K. and Tirri R. (1974), J. Neurochem. 23, 611-613) respectively, after preincubation with Phe. AChE activity in brain homogenate or in pure eel E.electricus enzyme showed a decrease, which reached up to 18% with concentrations of 0.9-12.1 mM. Brain homogenate Na+,K(+)-ATPase activity showed an increase 16-65% with 0.24-0.9 mM of Phe, while an activity increase of 60-65% appeared with 0.9-12.1 mM of Phe. Pure enzyme activity (from porcine cerebral cortex) was not affected by high Phe concentrations, while it was increased by low concentrations. The above results suggest: a) A direct effect of Phe on AChE, b) A direct effect of low Phe concentrations and an indirect effect of high ones on Na+,K(+)-ATPase.

Acetylcholinesterase↗
PubMedDate not supplied

In vitro influence of phenylalanine on acetylcholinesterase activity and DNA.

Acetylcholinesterase (AChE) is a significant component of the membrane contributing to the permeability changes during synaptic transmission and conduction. Phenylketonuria is a group of metabolic disorders in which phenylalanine (Phe) is highly elevated in blood (up to 0.1 M) resulting in mental retardation etc. AChE activity was measured spectrophotometrically after incubation with various Phe concentrations. Phe interaction with DNA was evaluated with an established HPLC method. Phe was found to inhibit AChE almost 40%, at a concentration of 5 mM, whereas a 62.5% DNA peak exclusion (molecular interaction) was observed when Phe was incubated with DNA at a concentration of 3 mM. In addition the ratio of DNA: Phe determined the potency of the observed molecular effect.

Acetylcholinesterase↗
PubMedDate not supplied

Protective effect of L-cysteine and glutathione on rat brain Na+,K+-ATPase inhibition induced by free radicals.

The aim of this study was to investigate whether the preincubation of brain homogenates with L-phenylalanine (Phe), L-cysteine (Cys) or reduced glutathione (GSH) could reverse the free radical effects on Na+,K+-ATPase activity. Two well established systems were used for the production of free radicals: 1) FeSO4 (84 microM) plus ascorbic acid (400 microM) and 2) FeSO4, ascorbic acid and H2O2 (1 mM) for 10 min at 37 degrees C in homogenates of adult rat whole brain. Changes in brain Na+,K+-ATPase activity and total antioxidant status (TAS) were studied in the presence of each system separately, with or without Phe, Cys or GSH. TAS value reflects the amount of free radicals and the capacity of the antioxidant enzymes to limit the free radicals in the homogenate. Na+,K+-ATPase was inhibited by 35-50% and TAS value was decreased by 50-60% by both systems of free radical production. The enzymatic inhibition was completely reversed and TAS value increased by 150-180% when brain homogenates were preincubated with 0.83 mM Cys or GSH. However, this Na+,K+-ATPase inhibition was not affected by 1.80 mM Phe, which produced a 45-50% increase in TAS value. It is suggested that the antioxidant action of Cys and GSH may be due to the binding of free radicals to sulfhydryl groups of the molecule, so that free radicals cannot induce Na+,K+-ATPase inhibition. Moreover, Cys and GSH could regulate towards normal values the neural excitability and metabolic energy production, which may be disturbed by free radical action on Na+,K+-ATPase.

Animals↗
PubMedDate not supplied

The effect of galactose metabolic disorders on rat brain acetylcholinesterase activity.

To evaluate whether in classical galactosemia galactose (Gal), galactose-1-phosphate (Gal-1-P) and galactitol (Galtol) affect brain acetylcholinesterase (AChE) activity, various concentrations (1-16 mM) of these compounds were preincubated with brain homogenates of suckling rats as well as with pure eel Electroforus electricus AChE at 37 degrees C for 1 h. Initially, Galtol (up to 2.0 mM) increased (25%) AChE activity which decreased. thereafter, reaching the control value in high Galtol concentrations. Gal-1-P decreased gradually the enzyme activity reaching a plateau (38%), when incubated with 8-16 mM. However, when the usually found 2 mM of Galtol and 2 mM of Gal-1-P, concentrations in galactosemia were added in the incubation mixture simultaneously, brain AChE was stimulated (16%). Galtol or Gal-1-P modulated brain AChE as well as enzyme activity of E.electricus in the same way. Gal, Glucose (Glu) and glucose-1-phosphate (Glu-1-P) had no effect on AChE activity. It is suggested that Galtol as well as Gal-1-P can affect acetylcholine degradation acting directly on AChE molecule. Consequently the direct action of these substances on the enzyme might explain the brain cholinergic dysfunction in untreated galactosemia patients.

Acetylcholinesterase↗