Nucleophilic N1-->N3 rearrangement of 5'-O-trityl-O2,3'-cycloanhydrothymidine

5'-O-Trityl-O2,3'-cycloanhydrothymidine (1) heated at 150 degrees C in the presence of O,O-diethyl phosphate or O,O-diethyl phosphorothioate anions undergoes rearrangement into N3-isomer (2); its structure was established by both advanced NMR methods and X-ray crystallographic studies. The most probable mechanism of 1-->2 rearrangement relies upon reversibility of glycosidic bond cleavage process.

[The osteoarthralgic symptoms preceding acute lymphoblastic leukemia]

Osteoarthralgia is a common symptom at the beginning of acute lymphoblastic leukaemia (ALL). It occurs in 40% of cases. Still arthritis that precedes haematological malignancies is very rare. However in every case of arthritis of unknown origin or drug resistance arthritis the bone marrow biopsy is required. We present 3 cases of osteoarthralgia that precedes ALL by 2.5-7 months.

[The efficacy of BFM-90 program in the treatment of acute lymphoblastic leukemia in children in the studies of Polish pediatric leukemia/lymphoma group]

Between years 1993 and 1998, 113 children aged from 6 months to 18 years (41 girls and 72 boys) with first relapse of acute lymphoblastic leukaemia (ALL) were included in the study. All children were treated according to BFM-90 relapse protocol. Thirty-two cases were classified as very early relapses, 56 as early and 25 as late relapses. Sixty-one children had isolated bone marrow relapse, in 30 children extramedullary relapse occurred (in 21 children in central nervous system and in 16 children in testes). There were 23 combined relapses. Remission was achieved in 12 children with very early relapse (78.12%), 32 children with early relapse (85.71) and 19 children with late relapse (96%). Event-free survival in 30 months of follow-up was 29.2%, 59.0% and 73.2% for very early, early and late relapses, respectively. Sixteen children with relapsed ALL after chemotherapy according to BFM-90 relapse protocol underwent high-dose therapy with hematopoietic stem cell transplantation (in 3 cases autologous and in 13 cases allogeneic). In 6 children isolated bone marrow relapse occurred after transplantation, all of them died during subsequent chemotherapy. Ten children is alive and well from 2 to 43 months after transplantation. The results obtained with BFM-90 chemotherapy in children with first early relapses are not acceptable. Such patients require high-dose chemotherapy and transplantation of hematopoietic progenitor cells.

[Long-term venous access "PORT": own experience]

In the study we analyzed the methods and results of implantation of 100 ports. Children age ranged between 0.5 and 16 years. All children received chemotherapy during neoplasm treatment. In conclusion, ultrasound detector, radiological control and subclavian venous access are safe and less traumatic than external jugular vein.

[Sepsis caused by Pseudomonas aeruginosa as the complication of induction treatment of acute non-lymphoblastic leukemia in a 10-year old girl]

We present a girl with acute non-lymphoblastic leukaemia (ANLL) who developed sepsis during the treatment of the disease. She was treated with BFM-83 protocol for ANLL. Blood cultured revealed the presence of Pseudomonas aeruginosa. This type of opportunistic infections are common, especially in patients with neutropenia.

[Clinical and biochemical picture of primary hyperparathyroidism based on 155 observed cases]

In this study, the biochemical and clinical profile of primary hyperparathyroidism, diagnosed in 155 patients (106 females and 49 males) in the Department of Nephrology of the Silesian University School of Medicine in the years 1972-1998 was analyzed. The mean age of patients was 48.5 +/- 12.8 years. In all cases the diagnosis was confirmed by the pathomorphological examination. In the majority of cases PNP was diagnosed in a phase of advanced organic injuries. The leading clinical finding in these patients was nephrolithiasis. Asymptomatic hypercalcemia was diagnosed only in 9% of cases. In the years 1972-1992 elevated serum total calcium concentration was found in 92.6% while after introduction of routine estimation of ionized calcium concentration in 1993, hypercalcemia was found in all patients. The incidence of hypercalciuria increased significantly in patients diagnosed in the period 1993-1998 while in this same period the incidence of impaired renal function declined significantly. The elevated serum PTH was found in 86% of patients regardless whether C-terminal fragments of PTH or intact PTH-1-84 were assessed. Elevated levels of ionized serum calcium with normal or increased plasma iPTH-1-84 level are the most constant symptoms of primary hyperparathyroidism.

Bicuculline administration into ventromedial hypothalamus: effects on fear and regional brain monoamines and GABA concentrations in rats

The effects of bicuculline methiodide administration into ventromedial hypothalamus (15 ng per site, bilaterally) on fear behavior and monoamines (NA, DA, 5-HT) and GABA in structures of the brain defensive system (hypothalamus, midbrain gray matter, amygdala, hippocampus and frontal cortex) were studied. Fear behavior was examined in the modified version of light-dark transition test. The time out from the illuminated compartment of chamber, the time spent there and number of returns to the illuminated compartment was measured. Additionally motor activity, i.e., number of crossings and rearings in dark as well as in the illuminated part of compartment, was registered. Blockade of GABAA receptors in the ventromedial hypothalamus resulted in increased fear behavior, i.e. decrease of time out from illuminated compartment and decrease of the time spent there. Motor behavior remained unchanged. HPLC analysis showed reduction of GABA concentration in all investigated brain structures. An increase of NA concentration in all examined structures with exception of the hypothalamus without effect on MHPG/NA was observed as well. Dopamine level remained unchanged, but DOPAC/DA ratio increased in all structures, except frontal cortex. Also HVA/DA ratio increased in the hypothalamus and midbrain. 5-HT concentration increased only in midbrain, 5-HIAA increased in midbrain and in frontal cortex, and 5-HIAA/5-HT ratio increased only in frontal cortex. These results indicate that GABA-ergic and monoaminergic systems remain in functional interactions and that these interactions may play an important role in the neurochemical regulation of fear behavior. The possible mechanism of GABA--monoaminergic interactions is discussed.

Biochemical characterization of alpha-ketooxadiazole inhibitors of elastases

A series of alpha-ketooxadiazole compounds was prepared and evaluated in vitro as potential inhibitors of human neutrophil elastase (HNE), proteinase-3 (PR-3), and porcine pancreatic elastase (PPE). Several compounds have been found to be very potent, fast, reversible, and selective inhibitors of HNE with Ki values below 100 pM. The highest kon value exceeded 10(7) M(-1) s(-1). Some alpha-ketooxadiazoles were also very effective against PR-3 and PPE with Ki values in the range of 5(-10) nM and 0.1(-2) nM, respectively. The two rings, 1,2,4- and 1,3,4-oxadiazole, are amenable to substitutions, extending the P' side of the inhibitor and allowing additional binding interactions at S' subsites of the enzyme. Nonpeptidic HNE inhibitors containing the oxadiazole heterocycle displayed promising oral bioavailability.

Converting enzyme-independent release of tumor necrosis factor alpha and IL-1beta from a stimulated human monocytic cell line in the presence of activated neutrophils or purified proteinase 3

Two important cytokines mediating inflammation are tumor necrosis factor alpha (TNFalpha) and IL-1beta, both of which require conversion to soluble forms by converting enzymes. The importance of TNFalpha-converting enzyme and IL-1beta-converting enzyme in the production of circulating TNFalpha and IL-1beta in response to systemic challenges has been demonstrated by the use of specific converting enzyme inhibitors. Many inflammatory responses, however, are not systemic but instead are localized. In these situations release and/or activation of cytokines may be different from that seen in response to a systemic stimulus, particularly because associations of various cell populations in these foci allows for the exposure of procytokines to the proteolytic enzymes produced by activated neutrophils, neutrophil elastase (NE), proteinase 3 (PR3), and cathepsin G (Cat G). To investigate the possibility of alternative processing of TNFalpha and/or IL-1beta by neutrophil-derived proteinases, immunoreactive TNFalpha and IL-1beta release from lipopolysaccharide-stimulated THP-1 cells was measured in the presence of activated human neutrophils. Under these conditions, TNFalpha and IL-1beta release was augmented 2- to 5-fold. In the presence of a specific inhibitor of NE and PR3, enhanced release of both cytokines was largely abolished; however, in the presence of a NE and Cat G selective inhibitor, secretory leucocyte proteinase inhibitor, reduction of the enhanced release was minimal. This finding suggested that the augmented release was attributable to PR3 but not NE nor Cat G. Use of purified enzymes confirmed this conclusion. These results indicate that there may be alternative pathways for the production of these two proinflammatory cytokines, particularly in the context of local inflammatory processes.

Behavioral and neurochemical alterations evoked by p-Chlorophenylalanine application in rats examined in the light-dark crossing test

The aim of the present study is to examine the effects of serotonin synthesis inhibition with p-Chlorophenylalanine (p-CPA) in rats on (1) anxiety behavior examined in the light-dark crossing test and, (2) regional brain concentration of monoamines (NA, DA and 5-HT) and their metabolites (MHPG, DOPAC, HVA and 5-HIAA) as well as GABA in the hypothalamus, amygdala, hippocampus, midbrain central gray matter and the frontal cortex. Treatment of animals with p-CPA produced a significant increase in time out from the illuminated part of the chamber and in time of locomotor activity in the illuminated part of the chamber. HPLC analysis showed a significant reduction of 5-HT and 5-HIAA concentration in all examined brain regions with the exception of the frontal cortex. Additionally, a significant decrease in DA and its metabolites, DOPAC and HVA occurred in the hypothalamus and amygdala. Moreover, we observed a significant decrease in frontal cortex NA concentration after p-CPA administration. The results of our study suggest that administration of p-CPA is effective in reduction of anxiety through depletion of 5-HT accompanied by diminution of catecholamines, especially DA and its metabolites in the main emotional brain regions.

[Transient loss of preexcitation by acute coronary ischemia--a case report]

We present a case of WPW syndrome with an accessory pathway in the right free wall. Two prolonged and failed attempts at radiofrequency catheter ablation of this accessory pathway in other institutions led to a third attempt in our hospital. With a 7F catheter in the right coronary artery, transient ischemia in the right ventricular myocardium developed with consecutive loss of bidirectional preexcitation within 45 seconds prior to catheter ablation. Removal of the guiding catheter, while the mapping catheter in the coronary artery was still in place, was reproducibly followed by the reoccurrence of the preexcitation pattern. Successful outcome of accessory pathway ablation was achieved by mapping the right free wall using an intracoronary catheter in the right coronary artery and ablating the accessory pathway using a modified long vascular sheet.

[Induction of atrial fibrillation by adenosine in a patient with supraventricular tachycardia]

Adenosine is generally considered to be safe and effective in treatment of orthodromic circus movement tachycardia in patients with accessory pathways. We present a case with reproducible induction of atrial fibrillation after initial successful termination of orthodromic circus movement tachycardia using a left sided accessory pathway by adenosine. With the induction of atrial fibrillation sudden onset of preexcitation with subsequent rapid ventricular response was accompanied by moderate hemodynamic compromise. Before and after successful ablation of the accessory pathway, adenosine was not able to induce atrial fibrillation when applied during sinus rhythm. Adenosine induced atrial fibrillation is due to shortening of the atrial action potential duration and atrial refractoriness, whereas shortening of the antegrade refractory period in the accessory pathway leads to rapid conduction to the ventricles. Thus, care should be taken using adenosine in patients with orthodromic circus movement tachycardias and evidence of antegrade preexcitation during sinus rhythm.

Bradykinin antagonists in human systems: correlation between receptor binding, calcium signalling in isolated cells, and functional activity in isolated ileum

The determination of the relationship between ligand affinity and bioactivity is important for the understanding of receptor function in biological systems and for drug development. Several physiological and pathophysiological functions of bradykinin (BK) are mediated via the B2 receptor. In this study, we have examined the relationship between B2 receptor (soluble and membrane-bound) binding of BK peptidic antagonists, inhibition of calcium signalling at a cellular level, and in vitro inhibition of ileum contraction. Only human systems were employed in the experiments. Good correlations between the studied activities of BK antagonists were observed for a variety of different peptidic structures. The correlation coefficients (r) were in the range of 0.905 to 0.955. In addition, we analyzed the effect of the C-terminal Arg9 removal from BK and its analogs on B2 receptor binding. The ratios of binding constants (Ki(+Arg)/Ki(-Arg)) for the Arg9 containing compounds and the corresponding des-Arg9 analogs varied from about 10 to 250,000. These ratios strongly depend on the chemical structures of the compounds. The highest ratios were observed for two natural agonist pairs, BK/des-Arg9-BK and Lys0-BK/des-Arg9-Lys0-BK.

Radiofrequency catheter ablation of a right atriofascicular (Mahaim) and two atrioventricular (Kent) accessory pathways in a single session

This report describes the case of a 19-year-old patient with Ebstein's anomaly, who had an unusual combination of a right atriofascicular (Mahaim) and two ipsilateral right atrioventricular (Kent) accessory pathways participating in three types of antidromic and orthodromic reciprocating tachycardias in the absence of retrograde conduction over the bundle of His-atrioventricular node axis. All three pathways were ablated in a single session using temperature-guided radiofrequency current.

[Obesity as the first manifestation of central nervous system involvement in acute lymphoblastic leukemia]

Obesity due to leukemic involvement of the hypothalamus may be the first manifestation of central nervous system (CNS) relapse. Hypothalamic syndrome may precede the appearance of lymphoblasts in the cerebrospinal fluid by a few months. We report a case of an 8-year-old girl with acute lymphoblastic leukemia who developed obesity, which was the first symptom of CNS relapse. A second remission and weight loss was achieved after intensive treatment.

Increased lipid peroxidation and antioxidant activity in methionine-induced hepatitis in rabbits

The liver is especially susceptible to the toxic effects of methionine due to its role in sulfur amino acid metabolism. Therefore, the excessive amounts of this amino acid may induce liver damage. To test the mechanisms of methionine-related hepatotoxicity, liver thiobarbituric acid reactive substances (TBARS), and activities of superoxide dismutase, catalase and selenium-dependent glutathione peroxidase were measured in rabbits fed a methionine-enriched diet for 6 or 9 mo. Morphological studies of livers were also made. Feeding rabbits the methionine-enriched diet for 9 mo resulted in a significant increase in liver TBARS levels and antioxidant enzyme activities. Moreover, an inflammatory infiltration of portal triads in the treated rabbits were observed. These results indicate that methionine may induce hepatitis by increasing free radical processes.

[Cat-scratch disease as a diagnostic problem of lymphadenopathy]

The diagnosis of cat-scratch disease is based on history and clinical symptoms. We present a case of a 4-year-old girl admitted to our unit with suspicion of histiocytosis X after histologic evaluation of a submandibular lymph node biopsy. On the basis of history, clinical features and histologic reevaluation, the diagnosis of cat-scratch disease was made.

Bradykinin receptor antagonists containing N-substituted amino acids: in vitro and in vivo B(2) and B(1) receptor antagonist activity

We report a systematic probing of the structural requirements of the bradykinin (BK) type 2 (B(2)) receptor for antagonist activity by incorporating N-alkyl-amino acid residues at positions 7 and 8 of a potent antagonist sequence. Compound 1 (D-Arg(0)-Arg(1)-Pro(2)-Hyp(3)-Gly(4)-Thi(5)-Ser(6)-D-Tic(7)-N-Chg (8)-Arg(9), CP-0597)(1,2) is a potent (pA(2) = 9.3, rat uterus; pK(i) = 9.62, binding, human receptor clone) B(2) receptor antagonist devoid of in vitro B(1) antagonist activity (rabbit aorta). Compound 1 exhibits high potency (ED(50) = 29.2 pmol/kg/min, iv, rabbit) and duration of action when tested in models for in vivo B(2) antagonist activity. Although devoid of activity in a classic B(1) isolated tissue assay, B(1) antagonist activity for 1 was demonstrated in vivo, in a LPS-treated, inducible BK(1) receptor rabbit blood pressure model (ED(50) = 1.7 nmol/kg/min). D-Arg(0) of 1 can be formally replaced by an achiral arginine surrogate, without significant loss in antagonist potency on rat uterus (compound 11, B(2) pA(2) = 9.1). Antagonist 13 (Hyp(2), Nchg(8)), pK(i) = 10.2, and agonist 4 (N-methylcyclohexyl-Gly(8)), pK(i) = 10.1, also exhibited substantial binding to guinea pig ileum membrane receptors as well as a human B(2) receptor clone. Very minor structural changes in the N-alkyl amino acid residues in positions 7 and 8 can modify the activity of this class of compounds from being extremely potent antagonists to tight binding partial or full agonists. These studies have resulted in a series of compounds containing inexpensive amino acid residues but which produce broad spectrum BK receptor blocking potency and exceptional in vivo duration of action.

[Nephrologic analysis of 94 women with diagnosed "primary" gestosis]

Among 94 women with diagnosed "primary" gestosis during pregnancy, 67 patients demonstrated (3-6 months after delivery) chronic glomerulonephritis (25 women) or chronic pyelonephritis (28 women) or hypertension caused by others than nephrologic reasons. "Primary" gestosis was diagnosed correctly only in 29% cases. The most often reason of "secondary" gestosis was undiagnosed chronic nephropathy before and during pregnancy. Obtained results confirm other data informing that "primary" gestosis is a rare phenomenon.

Increased lipid peroxidation as a mechanism of methionine-induced atherosclerosis in rabbits

Methionine is converted by the transmethylation/transsulfuration pathway to homocysteine which may exert atherogenic effects by several mechanisms, including lipid peroxidation. Therefore, the excessive dietary methionine may induce the development of atherosclerosis. To test this hypothesis, plasma and aortic thiobarbituric acid reactive substances (TBARS), as well as activities of aortic and erythrocyte superoxide dismutase (SOD), catalase and selenium-dependent glutathione peroxidase (GPX) were measured in rabbits fed a diet enriched with 0.3% methionine for 6 or 9 months. Histological examinations of aortas also were performed. Feeding rabbits a methionine-enriched diet for 6 or 9 months resulted in significant increases in plasma and aortic TBARS levels and aortic antioxidant enzyme activities. However, a decrease in plasma antioxidant activity (AOA) was observed. In erythrocytes, SOD activity increased, catalase remained normal and GPX decreased in the treated animals. Histological examination of aortas showed typical atherosclerotic changes, such as intimal thickening, deposition of cholesterol, and calcification in methionine-fed rabbits. These results confirm that high-methionine diet may induce atherosclerosis in rabbits and indicate disturbances in lipid peroxidation and antioxidant processes as possible mechanisms of its atherogenic influence.