Pharmacokinetics of recombinant human erythropoietin in children with chronic renal failure

Basal erythropoietin (Epo) levels and single dose-pharmacokinetics of recombinant human erythropoietin (rhuEpo) were investigated in 8 predialysis (PD) patients (mean age 11.6 +/- 1.4 years) and in 8 patients on continuous ambulatory peritoneal dialysis (CAPD) (mean age 12.7 +/- 0.6 years). Basal Epo levels were found to be 1.0 +/- 0.0 mu/ml in PD group, 1.6 +/- 0.7 mu/ml in CAPD group and 8.5 +/- 1.8 mu/ml in control group. Following administration of 50 mu/kg rhuEpo (s.c.) serum Epo concentration (Cmax) was 23.2 +/- 2.5 mu/ml in 18.5 +/- 2.6 hours (tmax) in PD patients and 9.9 +/- 0.8 mu/ml in 26.8 +/- 7.7 hours in CAPD patients. Mean elimination half-lives (t1/2) were 13.3 +/- 1.9 hours and 13.5 +/- 3.0 hours in PD patients and CAPD patients, respectively. The volume of distribution (Vd) was 840.0 +/- 100.0 ml/kg; the clearance (Epo Cl) was 37.0 +/- 5.5 ml/kg/hour in PD patients. These values were significantly lower in PD patients than in CAPD patients (p < 0.05) (Vd; 1500 +/- 240.0 ml/kg; Epo Cl 110 +/- 30.0 ml/kg/hour). During the course of CAPD, more efficient clearance of uraemic toxins that inhibit erythropoiesis and more rapid extraction of erythropoietin by erythroid precursors may cause higher Vd in CAPD patients than in PD patients.

Wilson disease mutations associated with uncommon haplotypes in Mediterranean patients

This study reports 12 novel mutations of the Wilson disease (WD) gene which have been detected by the molecular analysis of 29 patients of Mediterranean descent carrying uncommon chromosomal haplotypes at the WD locus. These mutations include two nonsense, one splice site and nine missense. The missense mutations lie in regions of the WD gene critical for its function, such as the transmembrane region, the transduction domain and the ATP loop and ATP-binding domain, indicating that they are disease-causing mutations. These new findings improve our knowledge for the role played by functional domains on the ATP7B function.

Direct detection of Hb C (B6 Glu-Lys) by BseRI analysis

Hemoglobin C (B6 Glu-Lys) can be identified by different techniques. Here we describe a restriction enzyme digestion protocol (BseRI GAGGAG N10) for direct detection of this variant.

A case of severe thrombocytopenia due to parvovirus B19 virus

A 9-year-old girl admitted with generalized skin, mucosa, and genitourinary system bleeding had anemia and thrombocytopenia. Her bone marrow was normocellular. Parvovirus B19 IgM and IgG were positive. An absence of reticulocytopenia suggested that the virus affected only the megakaryocytic cell line and the anemia was due to generalized bleeding resulting from thrombocytopenia. Intravenous immunoglobulin treatment was instituted. On the tenth day of hospitalization the patient recovered from anemia and thrombocytopenia. IgM antibodies disappeared.

Antibody response to measles vaccination in Turkish children

In recent years, there has been a remarkable increase in measles cases among preschool and secondary school children in Turkey, as in many other countries. The seroconversion and coverage rates of measles vaccine should therefore be evaluated in order to obtain data that could be used to determine the vaccination policy for Turkey. Measles immunity status was studied by an enzyme-linked immunosorbent (ELISA) test determining the anti-measles IgG antibody levels. Measles specific IgG antibodies were found to be positive in 77.88% of the entire study group of 800 children aged 11 months to 12 years, while 21.25% had negative sera. Seven (0.87%) subjects had borderline results. The results of this study indicate the need to administer a second dose of measles vaccine, preferably at 18 months of age concomitant with other vaccines. This vaccination policy, together with an increase in the extent of immunization coverage, may help to achieve the World Health Organization's (WHO) target of the complete eradication of measles.

p53 codon 213 (A-G) polymorphism in a Turkish population

We studied a rare polymorphism at exon 6 (CD 213) of the p53 gene in a healthy Turkish population (n = 26) and in Turks with different types of tumors such as malignant lymphoma (n = 12), osteosarcoma (n = 5), and nasopharyngeal sarcoma (n = 4). The polymorphic allele was found in only one of the malignant lymphoma patients (4.16%). Our data revealed that CD 213 (A-G) polymorphism is very rare in the Turkish population and there is no association with the tumors.

Tuberculous osteomyelitis: an unusual case of tuberculous infection in a child undergoing continuous ambulatory peritoneal dialysis

A 10-year-old boy on continuous ambulatory peritoneal dialysis had low-grade fever, pain and tenderness of the right shoulder; he had no history of infection or exposure to tuberculosis. The underlying granulomatous infection was diagnosed by histological examination of bone and the polymerase chain reaction with primer sequences specific for Mycobacterium tuberculosis. Special stains and cultures were negative. The initiation of antituberculous therapy was followed by a sharp improvement in the fever, malaise and shoulder pain within several weeks. Extrapulmonary tuberculosis is common in patients with chronic renal failure on dialysis and the diagnosis is difficult. The clinician must recognise the high and early mortality rate in order to initiate an aggressive diagnostic approach and early therapy.

Discrimination of Hb D Los Angeles (B121 Glu-Gln) and Hb Beograd (B121 Glu-Val) by dual restriction enzyme analysis

Hb D Los Angeles (B121 Glu-Gln) and Hb Beograd (B121 Glu-Val) can be identified by different techniques. Here we describe a dual restriction enzyme digestion protocol (EcoR IG AATTC) and Tsp509 I ( AATT) for the discrimination of these variants.

Effects of calcitonin therapy on osteoporosis in patients with thalassemia

The aim of this study was to evaluate the effects of calcitonin (CT) treatment on bone pain, osteoporosis, bone fractures and blood chemistry in thalassemic patients. Twenty-four patients with an age range of 10-24 years were included, 14 of whom received 100 IU CT and 250 mg calcium 3 times a week. The others (n = 10) were followed up as a control group with only routine thalassemia therapy. After 1 year of treatment, bone pain disappeared and radiological signs of osteoporosis had improved significantly (p < 0.01) in the treatment group. CT has no important side effects.

GM-CSF in the treatment of Fanconi's anaemia

We have used recombinant human (rh) GM-CSF in two 12-year-old Fanconi's aplastic anaemia patients. They had not received any previous therapy except blood transfusions. Each patient was given three 21 d courses of rh-GM-CSF, the first two at a dose of 3.5 micrograms/kg/d and the third at 7 micrograms/kg/d s.c. There were significant increases in WBC and absolute neutrophil counts after the first week of rh-GM-CSF which lasted as long as the treatment was continued. Following the cessation of treatment, WBC and ANC dropped rapidly. We conclude that rh-GM-CSF can be used in FAA, especially in severely neutropenic cases.

Desferrioxamine and urinary zinc excretion in beta-thalassemia major

This study has been undertaken to find out whether urinary zinc excretion, which is already increased in patients with thalassemia, is further increased by usual and high doses of desferrioxamine (DF). A total of 11 beta-thalassemia major patients were included. DF infusions have been performed with doses, either 50 mg/kg or 150 mg/kg. Nine age and sex matched normal children were taken as the control group. The mean basal-Zn excretion of the patients was significantly higher than the mean Zn excretion observed in controls. No significant difference is observed between the mean Zn excretion obtained on different doses of DF. However, they are both significantly higher than the mean basal-Zn levels of the controls.

Hemoglobinopathies in the district of Antalya, Turkey

A screening program was conducted to ascertain the incidence of hemoglobinopathies in the district of Antalya, Turkey. The survey sample was selected from the household registration forms of health centers by systematic random sampling. Heparinized blood samples were collected from 1,616 subjects from 884 families. The prevalence of beta thalassemia traits with increased Hb A2 was 10.2%. This is higher than that found in previous studies performed in Antalya. The prevalence of abnormal hemoglobins (Hbs) was found to be 0.8%. Four subjects had Hb AS; five had Hb D-Los Angeles (B 121 [GH4] Glu-Gln); one had Hb Ube-2 (68 [E1] Ans-Asp), one had Hb P-Nilotic (fusion between B 22 and) and two had Hb D-like variants.

Burkitt's lymphoma between African and American types in Turkish children: clinical, viral (EBV), and molecular studies

Seventy-two Turkish children with Burkitt's lymphoma (BL) observed during a period of 22 years (1968-1990) have been analysed retrospectively. The diagnosis was established histologically according to WHO criteria. BL represented 50% of NHL in this series. The patients were staged according to Ziegler's system. The median age of patients was 5.5 years with a sex (M/F) ratio of 2.1/1. The most common primary site of tumor involvement was the abdomen (69.4%), which was followed by facial tumors, in particular the jaw and orbit (49.9%). There were 21 cases with jaw (29.1%) and 15 cases with orbital involvement (20.8%) at initial presentation. The majority of the patients (84.4%) were in advanced stages (C and D) at initial diagnosis. Facial tumors observed in Turkish children with BL were more similar to African Burkitt's lymphoma than American or European cases. High titers of antibodies against VCA and EA of EBV were also seen in our recent cases of BL. Two main treatment regimens, namely, single agent chemotherapy with cyclophosphamide (CYX) (1968-1974) and three drug (COM) combination chemotherapy, were used consecutively (1974-1988). COM has been shown to produce better results than single agent therapy. The clinical presentation, mean age, and high antibodies (IgG) to EBV and preliminary molecular studies revealed that BL appears to be in between African and non-African types in Turkish children. This will be further elucidated by direct examination of tumor cells for EBV and investigation of the molecular characteristics of Turkish tumors. Such studies are presently under way.

Epstein-Barr virus genotypes in AIDS-associated lymphomas are similar to those in endemic Burkitt's lymphomas

PCR was used to screen EBV-positive lymphomas from endemic and sporadic Burkitt's lymphoma patients, including EBV-positive lymphomas derived from patients with HIV infection. Only 10% of sporadic lymphomas from either North America (1/15) or South America (2/14) were associated with the type 2 EBV strain, whereas 50% (8/16) of lymphomas from equatorial Africa and 46% (10/22) of HIV-associated lymphomas were positive for the type 2 strain. These data, in conjunction with previous reports, suggest that the proportions of strain types in Burkitt's lymphoma reflect the proportions of strain types in peripheral lymphocytes, and not simply the prevailing regional strain. The increased association of the type 2 strain in lymphocytes and lymphomas from HIV-infected individuals and from Africa may be a result of intermittent (malaria) or continuous (HIU) compromise of immune function in these populations.

Isolated growth hormone (GH) deficiency type IA associated with a 45-kilobase gene deletion within the human GH gene cluster

A Turkish family of seven individuals (two parents and five offspring) is described in which three children presented with isolated GH deficiency type IA, as defined by Illig et al. The gene deletion responsible for the isolated GH deficiency was characterized by Southern blotting and hybridization analysis of genomic DNA using a 32P-labeled hGH cDNA clone as a probe. In the affected patients, a total of approximately 45 kilobases of DNA, encompassing the human (h) GH-1, human chorionic somatomammotropin-L (hCS-L), hCS-A, and hGH-2 genes, were deleted. The end points of the deletion lay within two regions of highly homologous DNA sequence situated 5' to the hGH-1 gene and 5' to the hCS-B gene. The retention of only the hCS-B gene was associated with normal weight and length at birth and normal postpartum lactation in the mother heterozygous for the deletion. The parents, who are consanguineous, both presented with a DNA restriction pattern consistent with heterozygosity for this deletion.

The molecular basis of β-thalassemia in Turkey

By using oligonucleotide hybridization, restriction endonuclease analysis and direct sequencing of amplified genomic DNA, we have been able to characterize 18 different mutations in the beta-globin genes of 161 beta-thalassemia homozygotes and 107 beta-thalassemia heterozygotes from Turkey (429 beta-thalassemia chromosomes). Previous studies dealing with beta-thalassemia in Mediterranean countries have shown that, in most Mediterranean populations, only a few mutations are prevalent. In contrast, beta-thalassemia in Turkey does not seem to be associated with a few predominant mutations. The six most frequent alleles, IVS-I-110 (G----A), IVS-I-6(T----C), FSC-8 (-AA), IVS-I-1(G----A), -30(T----A) and FSC-5 (-CT), account for only 69.3% of the disease genes; indeed, all 26 mutations assayed represent 85.8% of the disease genes, confirming the considerable molecular heterogeneity of beta-thalassemia among Turks, and indicating the possible presence of rare, previously undefined, mutations in the population. Two mutations observed in this study, IVS-I-116 (T----G) and Cd44(-C), have not been reported in the Turkish population to date. Since preventive medical services, such as genetic counseling and prenatal diagnosis, are greatly improved by detailed knowledge of the molecular pathology of beta-thalassemia, we strongly believe that the presented data will facilitate the intended establishment of a prenatal diagnosis center, based on DNA analysis, in Turkey.

Maternal hair zinc concentration in neural tube defects in Turkey

Hair zinc concentration was measured in samples taken from 57 mothers who delivered infants with neural tube defects (NTD) (mainly anencephaly). Control groups consisted of 30 healthy mothers with normal offspring and 37 nonpregnant women from middle-income backgrounds. Zinc concentration was also measured in the hair of eight infants with NTD (four being anencephalic). The mean maternal hair zinc concentration in the NTD group (128.2 +/- 38.9 micrograms/g) was lower than that of the control women (p less than 0.001), whereas the mean hair zinc level of malformed babies (250.4 +/- 85.2 micrograms/g) was significantly higher than that of normal infants (193.4 +/- 39.2 micrograms/g) (p less than 0.05). Maternal nutritional zinc deficiency was thought to be one of the factors responsible for NTD in Turkey.

Effect of zinc supplementation in a Turkish woman with two previous anencephalic infants

The authors report a case of nutritional zinc deficiency in a young (18-year-old) Turkish woman, who previously delivered 2 anencephalic stillborn infants. The patient was supplemented with 22.5 mg oral zinc sulfate (100 mg ZnSO4.7H2O) for 5 months after her second delivery prior to her third pregnancy. Her blood (plasma and red blood cell) and hair zinc levels returned to normal following zinc supplementation. Good response to Zn supplementation was another criterion of Zn deficiency in this particular case. After an uneventful gestational period, she delivered an apparently normal full-term male child who has grown normally during the first 12 months.

Zinc status in pregnancy and the occurrence of anencephaly in Turkey

Serum and hair zinc concentrations were measured in samples taken from 29 mothers with neural tube defects (NTD) (mainly anencephaly) at delivery. The control group consisted of 20 healthy mothers with normal offspring and 40 nonpregnant women 18 to 34 years of age, from middle income backgrounds. The mean maternal serum and hair zinc concentrations in the NTD group were lower than those of control mothers and the nonpregnant women. The zinc levels in the blood (plasma, red blood cells) and hair of 8 newborn infants with NTD (4 being anencephalic) were compared with those of normal newborn infants. The mean zinc concentration in the hair of malformed babies (250.4 +/- 85.2 micrograms/g) was significantly higher than that of normal infants (193.4 +/- 39.2 micrograms/g) (p less than 0.05) while the mean plasma zinc concentration was significantly lower (59.48 +/- 9.18 micrograms/dl compared with 68.75 +/- 10.89 micrograms/dl) (p less than 0.01). No difference was found between the mean values of red blood cell zinc levels for the two groups of infants. Maternal zinc deficiency was thought to be one of the factors responsible for NTD in Turkey.

High incidence of neural tube defects in Bursa, Turkey

A radiological survey of 1204 members of the population of Bursa revealed a high prevalence of spina bifida occulta (16.3%). Hospital deliveries in the area also showed a high incidence of anencephalus and spina bifida aperta (5.8 per 1000 total births) in the years 1983 to 1986. In the first 6 months of 1987, however, there was an increase in incidence to 20 per 1000 births (P less than 0.01). The possibility is raised that the Chernobyl disaster of May 1986 might have resulted in the elevation of the rate in an already susceptible population.

Beta thalassaemia mutations in the Turkish population

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Effects of zinc supplementation on linear growth in beta-thalassemia (a new approach)

Linear growth was evaluated in 32 patients with beta-thalassemia major. At the beginning of the study of 40.6% of the patients were below the 10th percentile with biochemical evidence of zinc deficiency. Effects of zinc supplementation on growth velocity (height) were assessed in a controlled manner. Twenty-one children received oral zinc sulphate for a period of 1 to 7 years (15 early- and 6 late-supplemented cases), while the remaining 11 thalassemics were maintained only on conventional transfusion therapy. The mean height velocity of early-zinc supplemented children was significantly greater than that of normal children (P less than 0.01). An increase in height was also observed in the patients who received delayed zinc retardation. The present study demonstrated that zinc deficiency is one of the factors responsible for retarded linear growth in beta-thalassemia major. Only the patients who received zinc supplementation showed an acceleration of growth in height. Administration of zinc could, therefore, be considered as an effective adjuvant therapy in homozygous beta-thalassemia.

Zinc levels of serum, plasma, erythrocytes and hair in Turkish women with anencephalic babies

The present study revealed a significantly low zinc concentration, measured by atomic absorption spectrophotometry, in serum, plasma and erythrocytes of mothers with anencephalic babies as compared to two control groups of women. We feel that Turkey should be added to the list of geographic regions where zinc deficiency has been found together with a high rate of CNS malformations.

Serum copper and zinc levels and copper/zinc ratio in pediatric non-Hodgkin's lymphoma

40 patients, 15 females and 25 males, with biopsy-proven non-Hodgkin's lymphoma within the age range of 2-16 years were included in this study. The mean serum zinc level in 38 untreated patients was 78.95 +/- 18.80 microgram % and significantly lower than in controls (p less than 0.001). The mean serum copper level in 40 untreated patients was 205.32 +/- 49.44 microgram % and significantly higher than in controls (p less than 0.001). The mean copper/zinc ratio in these patients was 2.75 and was found to be significantly higher than in controls (p less than 0.01). Copper levels were lower during remission (p less than 0.05). Our data indicate that serum copper levels and the copper/zinc ratio might be indicators for disease activity in children with non-Hodgkin's lymphoma.