Polymorphic debrisoquin metabolism in a Turkish population.

Debrisoquin hydroxylation polymorphism was studied in 326 unrelated healthy Turkish volunteers. Debrisoquin sulfate (10 mg) was administered to subjects, and debrisoquin and 4-hydroxydebrisoquin were determined in the 0- to 8-hour urine samples. Debrisoquin oxidation was polymorphic, with 11 subjects (3.37%; 95% confidence interval, 1.69% to 6.07%) phenotyped as poor metabolizers. The metabolic ratio between debrisoquin and 4-hydroxydebrisoquin in 8-hour urine samples ranged from 0.02 in extensive metabolizers to 263.8 in poor metabolizers. The proportion of poor metabolizers was found to be in the range observed in the other white populations studied.

Effects of agmatine on ethanol withdrawal syndrome in rats.

Effects of agmatine, which is an endogenous polyamine metabolite formed by decarboxylation of L-arginine, have been investigated on the ethanol withdrawal syndrome in rats. Adult male Wistar rats were used in the study. Ethanol (7.2% v/v) was given to the rats by a liquid diet for 21 days. Agmatine (20, 40, 80 and 160 mg/kg) and saline were injected to rats intraperitoneally 30 min before ethanol withdrawal testing. After 30th min, 2nd and 6th h of ethanol withdrawal, rats were observed for 5 min, and withdrawal signs which included locomotor hyperactivity, agitation, stereotyped behavior, wet dog shakes and tremor were recorded or rated. A second series of injections was given at 6 h after the first one, and subjects were then tested for audiogenic seizures. Agmatine caused dose-dependent and significant inhibitory effects on stereotyped behaviors, wet dog shakes and tremors during the observation period. It did not cause any significant change in motor coordination of naive (not ethanol-dependent) rats. Our results suggest that agmatine attenuates withdrawal syndrome in ethanol-dependent rats; thus, this drug may be beneficial in the treatment of ethanol dependence.

Dihydropteridine reductase activity and neopterin levels in leukemias and lymphomas: is there any correlation between these two parameters?

Urinary neopterin levels, blood dihydropteridine reductase activity as well as other frequently used clinical parameters were evaluated in 110 patients suffering from various types of lymphomas and leukemias. Among them neopterin was detected as the most sensitive marker representing the severity of malignancy (p<0.00001). All patients with active diseases had significantly raised urinary neopterin levels compared to those in remission and healthy controls. Of 69 patients with active disease 66 (96%) were above the upper limit seen in healthy subjects. In addition, the highest neopterin excretion was found in patients with active chronic myeloid leukemia (1469+/-479 micromol/mol creatinine n=16). In contrast, only 1 of 41 patients in stable responsive disease and remission (2.4%) had increased urinary neopterin levels above the upper limit. Dihydropteridine reductase (DHPR) activities were also detected in all patients and control groups. In active disease slightly reduced (DHPR) activities were evident (3.42+/-0.37 for controls, 2.92+/-0.39 in active disease and 3.28+/-0.42 nmol red cytochrome C/min/5 mm diameter disc in remission patients). However in patients under medication this was strengthened. This data also suggest that DHPR activity can be effected by chemotherapy. The results of the present study support the fact that urinary neopterin levels may be an useful and reliable early prognostic marker for neoplasia when used together with other prognostic indicators. Our data also suggest that reductions in DHPR activities may also be an underlying cause for the neurological disorders that are commonly seen in patients with haematological malignancies.

Oxidative stress and nitric oxide related parameters in type II diabetes mellitus: effects of glycemic control.

OBJECTIVES: The aim of this study is to investigate the status of oxidative stress and nitric oxide related parameters in type II diabetes mellitus (DM) patients in which heart disease, atherosclerosis, retinopathy, and nephropathy commonly occur, and also to determine the effect of glycemic control on these parameters. DESIGN AND METHODS: Erythrocyte copper zinc-superoxide dismutase (CuZn-SOD), erythrocyte and plasma selenium dependent glutathione peroxidase (Se-GPx), erythrocyte catalase (CAT) activities, erythrocyte and plasma thiobarbituric acid reactive substances (TBARS) levels; nitrite/nitrate (NO(2)(-)/NO(3)(-)), cyclic guanosine monophosphate (cGMP) and nitrotyrosine levels in plasma of type II DM patients were measured. RESULTS: Erythrocyte CuZn-SOD activities in type II DM were significantly higher than those of the control subjects (p < 0.05). TBARS levels in type II DM were significantly higher than the control subjects (p < 0.001). Plasma NO(2)(-)/NO(3)(-) levels in type II DM patients both during poor glycemic control and after three months of oral antidiabetic treatment were significantly higher than those of the control subjects (p < 0.001). Plasma cGMP levels in type II DM patients during poor glycemic control were significantly lower than those of control subjects (p < 0.001). CONCLUSION: These results indicate that oxidative status and nitric oxide metabolism are affected in type II DM patients. We found high CuZn-SOD activity in type II DM patients. This increased activity could not protect the patients against the reactive oxygen species (ROS), since lipid peroxidation (defined by erythrocyte and plasma TBARS levels) still occurs in DM patients. After the therapy with oral antidiabetic agents for three months, erythrocyte SE-GPx and CAT activities were found to be decreased below the control values. Our results suggested that the low cGMP levels in the study may be a good marker of endothelium dysfunction in DM.

Beneficial effect of thyrotropin-releasing hormone on neuropathy in diabetic rats.

Thyrotropin releasing hormone (TRH) is therapeutically effective in experimental and clinical spinal injury. The effects of TRH on diabetic neuropathy are not known. The aim of the present study was to investigate the electrophysiological effects of TRH in the streptozotocin diabetic rats. Three groups of rats were studied, non-diabetic control (n = 10), diabetic controls (n = 8), and TRH treated diabetic rats (n = 9). Administration of TRH or saline and electrophysiological measurements were performed 4 weeks after induction of diabetes. TRH was given intraperitoneally in a dose of 600 microg (3 ml). Nerve conduction velocity (NCV), measured in caudal nerve, and N1 latency of somatosensory evoked potentials (SEP) were measured 75 min after injection of TRH or serum saline. SEP latencies were 28.1 +/- 0.6, 29.4 +/- 0.8, 27.8 +/- 1.1 ms, in normal, diabetic and diabetic TRH-treated groups, and NCV values were 28.1 +/- 0.8, 23.8 +/- 0.4, and 27.9 +/- 0.7 m/s respectively. NCV was significantly reduced in the diabetic group compared to normals (P < 0.05). but then improved by TRH treatment (P < 0.05). Our findings suggest that TRH has an acute effect on peripheral neuropathy in experimental streptozotocin diabetes in the rat.

Effects of neomycin on the development of tolerance to morphine antinociception.

The effects of neomycin on the development of tolerance to morphine antinociception were examined in mice. Because neomycin did not readly cross blood brain barrier, we examined the effects of neomycin following systemic, intracerebroventricular (i.c.v.) and intrathecal (i.t.) injections on the morphine tolerance. Daily subcutaneous (s.c.), i.c.v. and i.t. injections of morphine produced tolerance regardless of route of administration. Both i.c.v. and i.t. neomycin, which alone produced no changes in the basal tail flick latencies, significantly attenuated the development of tolerance to antinociception produced by repeated systemic morphine, while intraperitoneal (i.p.) administration of neomycin did not affect morphine tolerance. Further, i.c.v. and i.t. neomycin attenuated the development of tolerance to antinociception produced by repeated i.c.v. and i.t. morphine, respectively, which were not attenuated by systemic neomycin. This results indicate a potential role for neomycin-sensitive Ca2+ channels on the development of tolerance to the morphine antinoception.

Optimization of mobile phase in the separation of beta-blockers by HPLC.

Beta-blockers are generally determined using high-performance liquid chromatography (HPLC). Previous HPLC separations of beta-blockers have often required a mobile phase containing three components; acetonitrile or methanol to control the retention; buffer to control the ionic strength and pH of the mobile phase; ion-pairing reagent to provide adequate retention of beta-blockers or organic amines as masking agent to reduce peak tailing. Due to the complexity of the mobile phases employed, development of these assays can be a laborious process. Additionally, alkyl sulphonates and organic amines dramatically reduces the life-time reduction of silica based C18 columns. The results of this study demonstrated that the addition of tested alkyl sulphonates and organic amines is not essential for an adequate separation of beta-blockers. In this study, we developed a simple HPLC method for the simultaneous separation of model beta-blockers, atenolol, practolol, metoprolol, oxprenolol and propranolol. Atenolol, practolol, metoprolol, oxprenolol and propranolol adequately separated with high peak symmetries using a mobile phase consisted of methanol/acetonitrile/phosphate buffer (10 mM, pH 3.0) (15:15:70, v/v/v). By altering only the fraction of methanol with respect to acetonitrile, method development becomes a more efficient separation. Furthermore, atenolol, practolol, metoprolol, oxprenolol and propranolol can be detected up to 0.25, 5, 10, 50 and 10 ng ml(-1). In this publication, we present the simultaneous separation of beta-blockers having a wide range of polarity. It is proposed that this new mobile phase, consisting only acetonitrile, methanol and phosphate buffer can be used for the analysis of the several beta-blockers presently in doping control analysis as well as others.

Determination of debrisoquine and 4-hydroxydebrisoquine in urine by high-performance liquid chromatography with fluorescence detection after solid-phase extraction.

A simple, selective and sensitive method has been developed to determine debrisoquine and 4-hydroxydebrisoquine in human urine. Separation of the analytes was obtained using a mobile phase of 0.1 M sodium dihydrogen phosphate-acetonitrile (87:13, v/v) and a muBondapak C18 column. The column effluent was monitored with fluorescence detection at 210 nm (ex) and 290 nm (em). Rapid sample preparation was achieved by solid-phase extraction columns (Bond Elut CBA, 3 ml capacity) which provided excellent recovery values for both compounds. The cost per sample using this approach could be minimized by column regeneration and re-use. The within-day and the day-to-day reproducibilities were less than 7% for both components. The method was shown to be suitable for the study of the debrisoquine-sparteine type genetic polymorphism in man.

Aluminum content of vaccines used in Turkey.

Aluminum salts have been used in the preparation of a number of vaccines, toxoids, and allergen injectants as an adjuvant for many years. Although aluminum allergy is rare, there are many reported cases caused by aluminum-precipitated vaccines or hyposensitization therapy. Therefore, determination of the aluminum content of these vaccines is necessary information regarding adverse reactions related to these vaccines. In the present study, the aluminum contents of several vaccines (n = 19) routinely used in Turkey were, determined by electrothermal atomic absorption spectrophotometry. We found that aluminum levels in the vaccines ranged from 0.0 to 1438 mg/L.

Trace element (Al, Se, Zn, Cu) levels in serum, urine and tissues of burn patients.

Trace elements are known to play many important roles in humans. It has also been shown that some of these elements are essential in wound healing. In this study, aluminium, copper, zinc and selenium levels were determined in serum, urine and tissue samples of burned patients and the relationships between wound healing and trace elements were evaluated. Trace element levels were determined using atomic absorption spectrophotometry. During 20 days' treatment, a significant rise in aluminium levels was determined in serum, urine and tissue samples of patients. After day 5 of treatment, copper levels increased significantly only in urine samples. Zinc levels decreased in serum and tissue samples. However, zinc gave high values in urine within the first week then returned to the initial value. There was a significant decrease in zinc in serum and tissue samples taken from burned patients during treatment. Urine selenium levels showed a significant rise within the first 15 days.

Plasma glutathione peroxidase activity and selenium levels of newborns with jaundice.

The plasma glutathione peroxidase (GSH-Px) and selenium (Se) levels were determined in 31 newborns affected by jaundice (NWJ). The GSH-Px levels of both full-term and premature newborns exhibiting jaundice and having a birthweight lower than 2000 g were significantly low (p < 0.05) when compared to controls. No significant differences were found in the corresponding Se levels, which were similar in all groups and independent of the pregnancy period and birthweight.

Aluminum content of infant formulas used in Turkey.

In the past few years, there has been an upsurge of interest in aluminum (Al) and human health. The well-recognized manifestations of systemic Al toxicity include fracturing osteomalacia, dialysis encephalopathy, and microcytic hypochromic anemia. The role of Al in causing childhood diseases is also becoming clearer, but the safe plasma level still remains to be determined in newborns, especially in premature newborns, implying that it should be kept low. Premature infants receiving iv fluid therapy show evidence of Al loading. Additionally, the infant-feeding mixtures, especially the soy-based infant formulas, tested may be a significant additional source of Al in the diet of infants with low birthweights, and in infants and in young children with impaired renal function. Careful clinical and biochemical monitoring is warranted to determine whether it will be necessary to eliminate Al contamination of both oral and parenteral preparations used in infants and children who may be at risk for Al intoxication. In this present study, the Al content of infant feeds was measured by electrothermal atomic absorption spectrophotometry, and also compared with those of breast milk, cow's milk, milk powder, and some starches that are commonly used for preparation of infant feed in Turkey. Our results show that Al content of commercially available powdered infant formulas, most of which are imported from Europe, ranged from 1.211 to 10.925 micrograms/g. The mean value was higher than that of breast milk. It was also found that the Al content of cow's milk in various containers was higher than that of breast milk. The highest Al level among cow's milk samples was in the aluminized carton box.

Antioxidative metabolism in Down syndrome.

Down syndrome is the most common cause of mental retardation, affecting 1 in 700-800 liveborn infants. Although numerous biochemical abnormalities accompanying the syndrome have not yet been completely clarified, the antioxidant defense system enzymes have shown to be altered due to increased gene dosage on chromosome 21 and overproduction of superoxide dismutase (SOD-1 or Cu/Zn SOD). The purpose of this study was to investigate the activities of SOD-1 and glutathione peroxidase (GSH-Px) enzymes and the levels of their cofactors zinc (Zn), copper (Cu) and selenium (Se) in plasma of 20 Down syndrome patients. In comparison with age and sex-matched controls (n = 15), plasma GSH-Px, SOD, and Cu levels were significantly decreased in the patient group, but Zn and Se concentrations remained unchanged.

The aluminum content in some patch test allergens.

The Al content of 18 patch test allergens were measured by electrothermal atomic absorption spectrophotometry. It was found that these preparations contained Al in various amounts. We conclude that the presence of Al in patch test allergens may interfere with the diagnosis and evaluations of patients to whom the test is applied.

Selenium and Behçet's disease.

Behçet's disease is an inflammatory disorder of unknown etiology, characterized by recurrent oral and genital aphthous ulcers, ocular inflammation, and skin lesions of erythema nodosum and acneiform eruptions. Selenium (Se) affects all components of the immune system, i.e., the development and expression of nonspecific, humoral, and cell-mediated responses. In general, a deficiency in Se appears to result in immunosuppression, whereas supplementation with low doses of Se appears to result in augmentation and/or restoration of immunologic functions. In this study, the distribution of Se and IgG, IgM in serum were compared in samples from healthy adult control and Behçet's disease patients. The serum Se levels were measured by AA-30-40 Varian Spectra, and immunoglobulins were measured by immunodiffusion technique. The mean (SD) serum Se level of 54.24 +/- 8.06 ng/mL among Behçet's disease subjects was significantly different (P less than 0.01) from that in the control subjects (90.01 +/- 9.94 ng/mL). We also measured IgG and IgM as 10.01 +/- 2.74 mg/mL and 1.26 +/- 0.29 mg/mL, respectively for patients, and 15.08 +/- 4.73 mg/mL and 1.58 +/- 0.43 mg/mL for controls. The mean values of IgG and IgM for patients were significantly (P less than 0.05) different from the values of controls. It seems, therefore, that a deficiency in selenium impedes the humoral immune response.

Iodine and zinc, but not selenium and copper, deficiency exists in a male Turkish population with endemic goiter.

Although endemic goiter has been shown to have a high prevalence in Turkey, little is known about the concentration of urinary iodine, plasma selenium (Se), copper (Cu), and zinc (Zn) in these patients. We studied on 140 male patient with endemic goiter (mean age: 22.2 +/- 0.19 yr) and 140 healthy male subjects (mean age: 21.8 +/- 0.28 yr). Daily urinary iodine excretion was determined by the ionometric method. Plasma Se, Zn, and Cu were determined by using atomic absorption spectrometry. Daily urinary iodine excretion was found to be significantly lower in the patient group (38.7 +/- 2.26 microg/d) than that of controls (50.73 +/- 2.56 microg/day, p = 0.001). Plasma Zn concentrations were also found to be significantly lower in the patient group (1.04 +/- 0.03 microg/mL) than that of controls (1.16 +/- 0.02 microg/mL, p = 0.001). No significant difference was determined in Se and Cu concentrations between the patient and control groups. Our study shows that a moderate iodine deficiency exists in both patients with endemic goiter and control subjects, which indicates the important role of iodine deficiency in the etiopathogenesis of endemic goiter in Turkey. Zinc deficiency may also contribute to the pathogenesis of endemic goiter. However, Se and Cu do not seem to have any role in the etiopathogenesis of endemic goiter in Turkey. A community-based iodine fortification program throughout the country may be proposed to take over the problem, which also can prevent the contributing effects of other element deficiencies that occur when iodine deficiency is the prevailing factor.

Enhanced release of solid dispersions of etodolac in polyethylene glycol.

This work examines the release of etodolac from various molecular weight fractions of polyethylene glycol (PEG) solid dispersions. Solid dispersions of etodolac were prepared in different molar ratios of drug/carrier by using solvent and melting methods. The release rate of etodolac from the resulting complexes was determined from dissolution studies by use of USP dissolution apparatus 2 (paddle method). The physical state and drug:PEG interaction of solid dispersions and physical mixtures were characterized by X-ray diffraction (XRD), infrared spectroscopy (IR) and differential scanning calorimetry (DSC). The dissolution rate of etodolac is increased in all of the solid dispersion systems compared to that of the pure drug and physical mixtures. The solid dispersion compound prepared in the molar ratio of 1:5 by the solvent method was found to have the fastest dissolution profile. The physical properties did not change after 9 months storage in normal conditions.

Synthesis and antinociceptive activity of some 3-substituted benzothiazolone derivatives.

Thirteen 3-substituted benzothiazolone derivatives have been synthesized. Their chemical structures have been elucidated by IR and NMR spectral data and by elemental analyses. Among these compounds, 1-¿3-[2(3H)-benzothiazolon-3-yl[propanoyl]morpholine (5b); 1-¿3-[2(3H)-benzothiazolon-3-yl[propanoyl]-4-benzylpiperidine++ + (5c); 1-¿3-[2(3H)-benzothiazolon-3-yl[-propanoyl]-4-phenylpiperazine (5d); 3-[3-(4-benzylpiperidine-1-yl)propyl]-2(3H)-benzothiazolone (5k); 3-[3-(4-benzylpiperazine-1-yl)propyl]-2(3H)-benzothiazolone (5I); 3-[3-(4-phenylpiperazine-1-yl)propyl]-2(3H)-benzothiazolone (5m) have been found to be significantly more active than the others.

Clarithromycin targeting to lung: characterization, size distribution and in vivo evaluation of the human serum albumin microspheres.

Microspheres of clarithromycin have been prepared from human serum albumin using the emulsion polymerization technique. Albumin microspheres containing the active substance were injected into the tail vein of mice. Mice were sacrificed at intervals and microspheres collected from lungs and livers. The clarithromycin amount in microspheres was determined by reversed phase high performance liquid chromatographic (HPLC) method from the mice organs. Morphological and histopathological observations were also reported. The microsphere accumulation began at 10 min, and increased gradually until 6 h, then a decrease was observed. The microspheres were still present after 24 h. In the liver sample, no microsphere accumulation was observed at any time.

Omission of the deconjugation step in urine analysis and the unaltered outcome of CYP2D6 phenotyping with dextromethorphan.

The present study was aimed at determining whether the deconjugation step in chemical analysis could be omitted without altering the outcome of phenotyping CYP2D6 with dextromethorphan. This drug and its metabolite, dextrorphan, were assayed by high-performance liquid chromatography (HPLC) in urine. Urinary levels of dextromethorphan and dextrorphan with and without enzymatic (beta-glucuronidase) treatment of urine and the metabolic ratios for dextromethorphan were determined in 45 subjects. Although the enzymatic treatment did not alter the urinary concentration of dextromethorphan in both phenotypes, it increased the urinary concentration of dextrorphan in both poor and extensive metabolizers by 3.7- and 12.8-fold, respectively. A urinary unconjugated dextromethorphan/unconjugated dextrorphan metabolic ratio of 2.00 and a total dextromethorphan/total dextrorphan metabolic ratio of 0.30, respectively, identified three poor metabolizers. Enzymatic treatment decreased the urinary antimode value. Moreover, the urinary metabolic ratio based on unconjugated dextrorphan and dextromethorphan correlated well with that based on assay of total dextrorphan and dextromethorphan (rs = 0.9458, P < 0.001). The results show that urinary analysis of dextrorphan and dextromethorphan omitting the enzymatic deconjugation step is a fast, reliable and sensitive method and could be used for studying CYP2D6 type genetic polymorphism in man.