The clinical significance of MDR-1 gene expression in the hemopoietic cells of patients with acute leukemias in different phases of the disease

AIM: Analysis of cytostatic therapy effects on expression of gene MDR-1 in hemopoietic cells of patients with acute leukemia (AL) in complete clinicohematological remission (CCHR). MATERIALS AND METHODS: The study included 48 AL patients. 27 of them were untreated, 25 were resistant to or had recurrent AL. 4 patients were followed up. Bone marrow mononuclear fraction was investigated. Expression of MDR-1 gene in the cells was evaluated at hybridization. RESULTS: High expression of MDR-1 gene occurred in leukemic blast cells either upon achievement of CCHR or at least 6 months after its onset. When using schemes of chemotherapy containing two potential inductors of gene MDR-1, expression of this gene was registered significantly more frequently than in using schemes based on one inducing drug (p < 0.05). Frequency of occurrence of enhanced expression of gene MDR-1 in leukemic blasts significantly correlated with frequency of CCHR (p < 0.05). Correlation between occurrence of the gene's expression in normal hemopoietic cells in CCHR and occurrence of early AL recurrences was not found. CONCLUSION: The findings may facilitate design of new AL treatment programs.     

Polylysine decelerates kinetics of negatively charged gramicidin channels as shown by sensitized photoinactivation

Effect of a cationic polymer, poly(L-lysine), on the kinetic properties of ionic channels formed by neutral gramicidin A (gA) and its negatively charged analogue O-pyromellitylgramicidin (OPg) in a bilayer lipid membrane is studied using a method of sensitized photoinactivation. This newly developed method is based on the analysis of transmembrane current transients induced by a flash in the presence of a photosensitizer. It has been shown previously that the time course of the flash-induced current decrease in most cases follows a single exponential decay with an exponential factor (tau, the characteristic time of photoinactivation) that correlates well with the single-channel lifetime. Addition of polylysine does not affect tau for gA channels, but causes a substantial increase in tau for OPg channels. This effect is reversed by addition of polyacrylic acid. The deceleration of the photoinactivation kinetics is ascribed to electrostatic interaction of polylysine with OPg probably resulting in OPg clustering. The latter can stabilize the channel state by reducing the rotational and lateral mobility of OPg monomers and dimers, and thus increase the single channel lifetime.     

Relaparotomy]

The study of intrarenal and upper urinary tracts urodynamics in the presence of the ureteropelvic obstruction and of the function of the lower urinary tract shows that congenital hydronephrosis was in 42.8% of cases associated with bladder dysfunction presenting with hyperreflex-type dysfunction. Maladapted hyperreflex bladder was diagnosed in 29.4%, adapted--in 13.5% of cases. The hyporeflex dysfunction occurred in 15.9% of cases. The urinary bladder dysfunction in children with congenital hydronephrosis accounts for 58.7%. These aggravate the same defects of the upper urinary tracts and deteriorate the course of chronic obstructive pyelonephritis.     

Experience in the study of the effects of lead on the health status of children in Belovo]

Lead releases in Belovo town containing metallurgy enterprise had reached 120 tons/year earlier, but in recent years have decreased to 9 tons/year. Reduction of the production induced decrease of lead levels in the ambient air from 0.7-2.3 mg/m3 in 1994 to 0.001-0.24 mg/m3. Lead concentration in the soil ranges from 30 to 3000 mg/kg. Lead levels were measured in serum of 91 children, in hair of 67 ones and in teeth of 15 children. Serum lead levels in children aged 7-8 years varied from 0.5 to 39 mg/dl, with an average of 9.9 mg/dl (SD is 5.2 mg/dl), geometric mean is 8.5 mg/dl and error of geometric mean is 3.3. 46% of the children had serum lead levels exceeding the normal one (10 mg/dl). Average lead level in the hair equaled 4.5 mg/g (SD is 4.9 mg/g). The children living in towns with higher environmental lead levels demonstrated more frequent anxiety and changes in higher psychic functions. The major points influencing the serum lead level are proximity to highway, dietary load of goods grown near the residence, mother's smoking. Biokinetic model describing lead transfer into the blood helped to evaluate various modes of the enterprise functioning and efficiency of some environmental protection measures. The most efficient are measures aimed to lower dietary intake of lead, less efficiency is associated with measures reducing lead levels in air, dust and soil.     

Congenital cystic diseases of liver and extrahepatic bile ducts

The paper presents 30-year experience in treating 158 patients with congenital cystic diseases of the liver and bile ducts. Depending on the pattern of hepatobiliary lesions, the diagnostic value of techniques, such as ultrasound, computerized tomography, scintigraphy of the liver duodenoscopy with THCG was defined. Analyzing the late outcomes provided recommendations for the most optimal surgical management: cystic fenestration and tunneling in hepatic polycystosis, pericystectomy in solitary cysts of the liver, different varieties of bile draining operations in choledochal cysts and Caroli's disease.     

Influence of mass transfer and surface ligand heterogeneity on quantitative BIAcore binding data. Analysis of the interaction of NC10 Fab with an anti-idiotype Fab'

The interaction of monovalent Fab fragments of NC10, an antiviral neuraminidase antibody, and the anti-idiotype antibody 3-2G12 has been used as a model system to demonstrate experimentally the influence of non-ideal binding effects on BIAcore binding data. Because the association rate constant for these two molecules was found to be relatively high (about 5 x 10(5) M-1 S-1), mass transfer was recognised as a potential source of error in the analysis of the interaction kinetics. By manipulation of the flow rate and the surface density of the immobilised ligand, however, the magnitude to this error was minimised. In addition, the application of site-specific immobilisation procedures was found to improve considerably the correlation of experimental binding data to the ideal 1:1 kinetic model such that the discrepancy between experimental and fitted curves was within the noise range of the instrument. Experiments performed to measure the equilibrium constant (KD) in solution resulted in a value of similar magnitude to those obtained from the ratio of the kinetic rate constants, even those measured with a heterogeneous ligand or with a significant mass transfer component. For this system, the experimental complexities introduced by covalent immobilisation did not lead to large errors in the KD values obtained using the BIAcore.     

Metabolism, intensity of lipid peroxidation and the antioxidant defense system in humans during chamber experiments with long-term isolation

Blood biochemical parameters of lipid, protein, carbohydrate and energy metabolism were measured in a 135-day chamber experiment. Also, dynamics of the intensity of lipid peroxidation and status of the antioxidant defence system were evaluated. Results of the investigation showed that extended chamber isolation led to modifications of several biochemical parameters including hemoglobin, bilirubin, cholesterol and its fractions, elevated transaminase activity which are typical for long-term space mission. However, these were not accompanied by substantive changes in protein, energy and carbohydrate metabolisms, or intensity of free radical processes. Effects of prolonged stay in chamber was successfully counterbalanced by organism.     

Selection of serum deproteinization methods

Dentists are often called upon to perform painful procedures on children. This may present a management problem for the practitioner who is unfamiliar with accepted behavioural management techniques or prescribing analgesics for paediatric patients. This article will review techniques that may be used to guide a child patient's behaviour through painful procedures as well as addressing the need for post-operative analgesics in the paediatric population.     

Serotonin 5-HT2 receptors in schizophrenia: a PET study using [18F]setoperone in neuroleptic-naive patients and normal subjects

BACKGROUND: In the FRISC trial, dalteparin 120 IU/kg body weight twice daily for unstable coronary artery disease was safe and reduced the risk of new coronary events. This risk reduction was maintained during the following extended treatment with a fixed dose of 7500 IU dalteparin once daily. METHODS AND RESULTS: Minor bleeding was more frequent in women compared with men: relative risk (CI) 2.88 (1.78 to 4.67) during the weight-adjusted and 2.36 (1.37 to 2.63) during the fixed dose treatment. The anti-Xa activity determined in samples (n = 175) obtained during the acute phase treatment was higher in women compared with men (P <.001) and in nonsmokers compared with smokers (<.001) in multiple regression analysis. Also, during the fixed-dose treatment (n = 131) an independent relation between anti-Xa activity and sex (P <.001), but not smoking habits, persisted. CONCLUSION: To improve future low-molecular-weight heparin dose regimens for the treatment of acute coronary syndromes, it might be important to consider the influence of sex and smoking habits.