Canan Çoker

Proinflammatory cytokines, prostaglandins and zinc in febrile convulsions

Abstract 
 Background : Some changes in the levels of proinflammatory cytokines, prostaglandins and zinc (Zn) in peripheral blood and cerebrospinal fluid (CSF) have been suggested to occur for the pathogenesis of febrile convulsions (FC).

Sequential Use of Deferiprone and Desferrioxamine in Primary School Children with Thalassaemia major in Turkey

The effectiveness of the sequential use of deferiprone and desferrioxamine (DFO) in children with thalassaemia major was examined. Seven thalassaemic children in whom urinary iron induced by deferiprone was sufficient to maintain a negative iron balance were enrolled in the long-term trial. Deferiprone at a dose of 75 mg/kd/day in 3 divided doses was given for 4 school days a week. The group was given DFO at a dose of 40–50 mg/kg/day s.c. over 8–12 h with a battery-operated pump for 2 days at the weekend. In addition to the safety variables, they were monitored for serum ferritin levels at 2-month intervals and hepatic iron concentrations in liver tissues were determined at the beginning and the 6th month of therapy. The severity of hepatic damage was graded according to the Knodell hepatic activity index and the fibrosis was quantified. None of the patients suffered adverse effects of the therapy but a transient increase in serum ALT levels was noted. A nonsignificant decline in serum ferritin was observed (p = 0.08), a significant reduction in hepatic iron concentration was also determined (p = 0.03). The hepatic activity index in liver tissues of the patients at the 6th month of the sequential therapy significantly decreased (p = 0.03) whereas fibrosis scores did not differ significantly (p = 0.25).

HYPOZINCAEMIA IN FEBRILE CONVULSION

To understand further the role of trace elements in the pathogenesis of febrile convulsions, serum zinc (Zn), copper (Cu), magnesium (Mg) and CSF Zn, Cu, Mg and protein levels were measured by spectrometry in patients with febrile convulsion (n=19), bacterial meningitis (n=9), viral CNS infection (n=16) and in the control groupn=10) which consisted of children with signs of meningeal irritation due to upper respiratory tract infection but normal CSF findings. Samples were obtained within 6 h after admission to hospital. Mean serum and CSF Zn levels in the febrile convulsion group were significantly lower than in the other groups (for serum Zn: 0.66±0.03 mg/l vs 0.98±0.07 mg/l, 1.06±0.08 mg/l, 1.05±0.09 mg/lP<0.05; for CSF Zn: 22.96±1.62 μg/l vs 75.47 ±6.9 μg/l, 50.32±5.235 μg/l, 39.85 ±2.81 μg/lP<0.05). A linear relationship was established between serum Zn and CSF Zn levels (P<0.001). Mean CSF Zn, Cu and protein levels in the bacterial meningitis group were significantly higher than in the other groups (for CSF Cu 63.94±6.33 μg/l vs 38.77±2.70 μg/l, 35.84±3.48 μg/l, 33.86±2.88 μg/lP<0.05; for CSF protein 0.80 ± 0.12 g/l vs 0.22±0.02 g/l, 0.53±0.08 g/l, 0.19±0.01 g/lP<0.05). In children with meningitis, the elevation of the mean CSF Zn and Cu levels may result from the breakdown of the blood-brain barrier and subsequent leakage of trace elements and protein from serum to CSF. There was no significant difference between the four groups in terms of mean serum Mg and mean CSF Mg levels.ConclusionSerum and CSF Zn levels are decreased in children with febrile seizures. Zinc deprivation may play a role in the pathogenesis of febrile seizures.

Cadmium exposure in tobacco workers: possible renal effects

Cadmium is a nephrotoxic metal widely used in industry and the main source of Cd in general population is smoking. Considering that the source of Cd in cigarettes is the tobacco leaf, the exposure to Cd was evaluated in workers employed at a tobacco leaf processing factory. Blood and urinary Cd levels were measured by flameless atomic absorption spectrometry in 87 workers and 35 controls. Urinary enzymes, total protein, albumin and uric acid were also determined to investigate the possible nephrotoxic effects of Cd. Blood Cd levels were significantly higher in workers (1.63 +/- 1.95 microg/L) than in controls (0.91 +/- 1.15 microg/L) (p = 0.044). The increase observed in urinary Cd levels of workers was non significant (0.56 +/- 0.5 microg/g creatinine in workers and 0.46 +/- 0.5 microg/g creatinine in controls). Both in workers and in controls, subjects smoking >10 cigarettes/day showed significantly increased blood Cd levels compared to non-smokers (p = 0.000 and p = 0.011, respectively). In workers, urinary alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), total protein, and uric acid were observed to be significantly increased (p = 0.013, p = 0.000, p = 0.000, p = 0.025, respectively), ALP, GGT and total protein being positively correlated with Cd in urine. In conclusion, the workers in the tobacco leaf processing factory were found to be exposed to Cd compared to the general population. The increase in the urinary enzymes and proteins suggests that an exposure to Cd affects kidney functions even below the toxic limits generally accepted.

Urinary zinc excretion and zinc status of patients with beta-thalassemia major

In this study, zinc status and urinary zinc excretion with and without desferrioxamine (DFO) infusion and the relationship between urinary zinc excretion and renal tubular dysfunction in thalassemia major (TM) patients were investigated. Forty TM patients were given four DFO infusions on alternate days over a 1-wk period prior to the transfusion. On each day that DFO was given, a 24-h urine collection initiated. DFO was omitted for 1-wk before the following transfusion and during the period four 24-h urine collections were performed. Twenty healthy children provided 24-h urine collection as controls. Blood samples were taken on each of two consecutive transfusion days of the patients and from the controls. Urinary zinc excretion was measured and plasma and red blood cell (RBC) zinc analysis were performed by inductively coupled plasma-atomic emission spectrophotometry. UrinaryN-acetyl-Β-D-glucosaminidase (NAG) activity and creatinine were determined in morning urine specimens. The mean plasma zinc concentration was significantly lower in the patients not given DFO compared to the values of the patients given DFO and the control group. The mean RBC zinc concentration (Μmol/g Hb) in the patients (with and without DFO) and the control group were similar. Urinary zinc excretion was significantly higher in the patients receiving DFO compared to the control group, whereas urinary zinc excretion in the patients not given DFO was not different from the controls. Urinary NAG indices (U/g Cr) were significantly higher in the patients compared to controls. Urinary zinc excretion was correlated with the urinary NAG indices.

Lymphocyte subpopulations in children with vitamin D deficient rickets.

Recent studies have shown 1,25(OH)2D3‐mediated modulation of the immune system. We examined lymphocyte subpopulations of 16 children with nutritional rickets. Most of the patients suffered more frequent infection episodes than the control group of 15 healthy children and low serum levels of 25OHD and 1,25(OH)2D, such as 38.2 ± 8.6 ng/mL and 15.7 ± 2.6 pg/mL respectively. This decrease correlated with a significant decrease in total T lymphocytes and an increase in B lymphocytes expressing surface IgA, IgM, IgG molecules. These results suggest that vitamin D plays an important role in the impaired functions of T lymphocytes which may lead to frequent infection episodes in nutritional rickets.

The effects of different syringe volume, needle size and sample volume on blood gas analysis in syringes washed with heparin.

Introductıon: We evaluated the effect of different syringe volume, needle size and sample volume on blood gas analysis in syringes washed with heparin. Materials and methods: In this multi-step experimental study, percent dilution ratios (PDRs) and final heparin concentrations (FHCs) were calculated by gravimetric method for determining the effect of syringe volume (1, 2, 5 and 10 mL), needle size (20, 21, 22, 25 and 26 G) and sample volume (0.5, 1, 2, 5 and 10 mL). The effect of different PDRs and FHCs on blood gas and electrolyte parameters were determined. The erroneous results from nonstandardized sampling were evaluated according to RiliBAK’s TEa. Results: The increase of PDRs and FHCs was associated with the decrease of syringe volume, the increase of needle size and the decrease of sample volume: from 2.0% and 100 IU/mL in 10 mL-syringe to 7.0% and 351 IU/mL in 1 mL-syringe; from 4.9% and 245 IU/mL in 26G to 7.6% and 380 IU/mL in 20 G with combined 1 mL syringe; from 2.0% and 100 IU/mL in full-filled sample to 34% and 1675 IU/mL in 0.5 mL suctioned sample into 10 mL-syringe. There was no statistical difference in pH; but the percent decreasing in pCO2, K+, iCa2+, iMg2+; the percent increasing in pO2 and Na+ were statistical significance compared to samples full-filled in syringes. The all changes in pH and pO2 were acceptable; but the changes in pCO2, Na+, K+ and iCa2+ were unacceptable according to TEa limits except fullfilled-syringes. Conclusions: The changes in PDRs and FHCs due nonstandardized sampling in syringe washed with liquid heparin give rise to erroneous test results for pCO2 and electrolytes.

Carnitine metabolism in diabetes mellitus.

In diabetes mellitus (DM), increased fatty acids have negative effects on pancreatic beta-cell functions, in addition to enhanced mitochondrial transportation of fatty acids related to decreased insulin levels. The aim of this study was to evaluate lipid metabolism in children with DM by measuring plasma fatty acids and carnitine fractions to reveal relationships between carnitine status and increased fatty acid oxidation. Increased plasma fatty acids (except for arachidonic acid, there were no significant differences in the ratio of each specific fatty acid to total fatty acids), lipoprotein (a), acyl carnitine levels and urinary total and free acyl carnitine excretion, and decreased plasma free carnitine levels, were found in children with DM. There were no correlations between the duration of DM or HbA1c and study parameters. It is recommended that plasma free carnitine determinations should be made even if the patient has good metabolic control.

Infantile spasm: the effect of corticotropin (ACTH) on the free amino acid profile in cerebrospinal fluid

Increased excitatory amino acid neurotransmission has been implicated in the pathogenesis of infantile spasm. In this study we studied the profile of free amino acids in cerebrospinal fluid (CSF) from 16 patients with infantile spasm before corticotropin (ACTH) treatment. After 10 weeks ACTH therapy the profile of amino acids in CSF was studied once more in eight of the patients. Eleven patients were in the symptomatic group, and five in the cryptogenic group. Increased aspartate levels were measured in CSF following ACTH therapy (P<0.05). It was concluded that aspartate might have an important role in hypothalamic-hypophyseal axis in patients with infantile spasm.

Serum malondialdehyde levels in preterm and fullterm infants undergoing phototherapy

Sir, Human chitotriosidase is a recently identified enzyme that belongs to the chitinase family. In contrast to the other mammalian chitinases, it is a functional chitinolytic enzyme (1). In the present study we had the opportunity to assay for chitotriosidase activity (1) in serial plasma and urine samples taken from a neonate with systemic fungal infection. All the studies at the Institute of Child Health are approved by the Institute’s Ethical Committee. The index case was admitted to the neonatal intensive care unit because of poor feeding, pyrexia and irritability. Chitotriosidase activity in plasma was assayed for the first time on the 15th day of hospitalization (I) when Candida albicans-positive venous blood and urine cultures were obtained. Assays were also performed in consecutive plasma and urine samples (I–V) taken at approximately 1 week intervals for the following 5 weeks. At that point neither hyphae nor growth on culture had been observed in three consecutive samples of urine. Increased plasma (I:88, II:105, III:80, IV:57, V:53; controls of similar age group 39, 39, 25, 14 nmol/ml/h) and urine (I:not determined, II:440, III:67, IV:4, V:0; controls of similar age: 3, 7, 5, 0 nmol/mg creatinine/h) chitotriosidase activity, as compared to controls, was found in the initial samples obtained from our patient, that decreased over the period studied. In fact by the end of the 5-week period, when no microbes could be cultured, the chitotriosidase activity had reached a completely normal level in urine and showed a very modest elevation in plasma compared to controls. The reduction of chitotriosidase levels ran in parallel to the improvement of the clinical condition of the patient as well as that of other laboratory parameters, in particular WBC counts and erythrocyte sedimentation rate. The observed reduction was not due to the inhibition of chitotriosidase by the administered anti-fungal drugs, since the activity in samples prepared by mixing plasma from the index case and patients with high chitotriosidase activity, ranged from 95 to 100% of the expected sum of the individual activities. Using a neutralizing anti-human chito riosidase antiserum (1), it was noted that chitotriosidase activity in plasma and urine samples from the patient was always inactivated by.95%, indicating that it originated predominantly from phagocytes of the patient. The role of the human chitinase is still an open question. In chitin-containing organisms, chitinases are believed to participate in morphogenesis, host–parasite interactions and their defence against fungal infection (3). The observation that in humans the enzyme is expressed in cells involved in defence mechanisms and increased synthesis occurs in stressed macrophages, suggests a similar to the latter role in humans (1, 2). Our observations support such a role. Furthermore they indicate that serial estimations of the enzymic activity could be exploited to monitor the r sponse to the applied therapy in fungal infections. Further studies involving not only chitotriosidase measurements in more patients, but also the investigation of other parameters such as mRNA synthesis and expression in cells of the immune system during fungal infections, will be very important in elucidating the role of the human enzyme in the defence against chitin-containing microbes.