Lipoblastoma in children: an analysis of 5 cases.

Lipoblastoma is a very rare benign tumour that is caused by embryonal fat. The present five cases of lipoblastoma operated on during the years 1996-2005. The localization of the lipoblastomas in our series were very unusual. A six-monthold girl with giant mediastinal lipoblastoma; a two-year old boy with very rare lipoblastoma of the kidney; a three-year old boy with mesenterial lipoblastoma; a seven-year old boy with mesenterial lipoblastoma; and an eight-week old girl with perineal localization. Histological diagnosis can be difficult. The basic differential diagnosis is to be made between lipoblastoma, myxoid, and round cell liposarcoma. In our sample group of patients all lipoblastomas were successfully and completely removed and we did not see any recurrence of the tumours. In only one case was more radical surgery needed. One patient with mesenterial lipoblastoma had to undergo a 30 cm long resection of the small intestine.

Impact of the Bohunice Nuclear Power Plant on atmospheric radiocarbon.

Radiocarbon variations in the atmospheric CO(2) have been observed at two localities in Slovakia (Bratislava and Zlkovce). Zlkovce is situated about 60 km NE from Bratislava, and only 5 km from the Bohunice Nuclear Power Plant (NPP). The observed Delta(14)C levels provide a unique evidence of the long-term impact of the Bohunice NPP on the Bratislava region, as well as on the decreased fossil fuel CO(2) emissions. The radiation doses estimated to the local public have been around 3 microSv/year, 20% of the dose from global fallout (14)C present in the environment.

Multiple fibroepithelial polyps of the upper ureter in a 17-year-old boy--case report and review of the literature.

Benign tumours and primary malignant tumours of the ureter are uncommon in adults and extremely rare in children. The clinical symptoms are flank pain, urinary tract infection, and macro/micro-haematuria. There is an incomplete ureteral obstruction and filling defect on intravenous urography (IVU). Optimum treatment of this lesion results in renal preservation. Uretero-renoscopy is currently the best method available for the identification and histological diagnosis of ureteral polyps. Recommended operative procedures are pyeloureteric junction (PUJ) resection with Anderson-Hynes pyeloplasty, ureteric resection with end-to-end anastomosis or with uretero-cysto-neoanastomosis (UCNA), ureteric resection with renal autotransplantation. Ureteronephrectomy is not indicated. A case of ureteral polyps in a 17-year-old boy with the chief complaint of left flank pain is reported here. The excretory urogram and renal scan showed left hydronephrosis. Resection of the pyeloureteral junction, partial resection of the upper ureter containing the lesions--multiple branching 30-40 mm long polyps with a common basis--and Anderson-Hynes pyeloplasty were performed. The pathological diagnosis was benign fibroepithelial polyps of the ureter. Convalescence was uneventful and after 4 years of follow-up, excretory urogram and ultrasonography showed good renal function and improvement of hydronephrosis.

[Treatment of hypospadias in childhood]. / Lécba hypospadie v detském veku.

The aim of the paper is to compare different techniques of correction of hypospadias with the author's own group of patients and to compare the results with those achieved at other departments. Between 1992-1999 at the Department of Paediatric Surgery, Teaching Hospital Motol 348 operations were made in 219 boys. A plastic operation with a distal shift of the urethra a and conization of the glans in 112 patients predominated. Other methods included in 39 patients the creation of a ventral circumference of the urethra from the inner laver of the prepuce while preserving the urethral plate ("onlay island flap") and a parameatally everted flap according to Mathieu in 11 patients. A plastic operation by complete tubulization of the inner laver of the prepuce was used in 19 patients, in 2 boys the method of Duplay-Byars tubulization of the urethral plate. In one patient the urethra was replaced by a free flap as described by Nove Josserand. Another 129 operations included formerly used and now abandoned two-stage operations to straighten the penis, operations to reconstruct the prepuce and operations on account of complications. The latter comprised 16.4% fistulae, 9.58% dehiscences and 1.36% strictures.

[Renal transplantation in children in the Czech Republic]. / Wyniki przeszczepiania nerek u dzieci w Republice Czeskiej.

The aim of the study is to review results of pediatric renal transplantation in center in Prague, Czech Republic. Results are compared with the registry data from Europe and United States. Patients, who underwent RTx at the University Hospital Motol, Prague (Czech Republic) between 1977 and the end of 1999, were analyzed. Since 1977 128 Rtx from cadaveric donors were performed in children in mean age 12.8 +/- 4.1 years. In 1977-1987, patients were treated with prednisone and azathioprine, and since 1988, cyclosporine A, added to prednisone and azathioprine. Sequential quadruple immunosuppression was used only in few highly sensitized patients. Acute graft rejections were treated with methylprednisolone pulses, antithymocyte globulin and monoclonal antibodies OKT3, in selected cases. In 1988 and 1999 cyclosporine A was replaced by tacrolimus as initial immunosuppression in some patients. The number of Tx ranged between 5 and 13 per year. Patients and graft survival were significantly lower in the first time period 1977-1987 with a median patients 5-year survival rate of only 50% and graft survival 30%. In the last period (1988-1999) 5-year patients survival is 90% and 5-year graft survival is 68% (p = 0.01). Two cases of posttransplant lymphoproliferative disease were diagnosed so far. One of them died several months after RTx, the other received cytostatic therapy for Hodgkin tumor and graft function was maintained. Main causes of graft failure were chronic rejection followed by acute steroid resistant rejections, severe cytomegalovirus infections, noncompliance, vascular thrombosis, and recurrence of original disease.

Cellular pharmacology of the D- and L-enantiomers of beta-5-o-carboranyl-2'-deoxyuridine.

The cellular pharmacology of the D- and L-enantiomers of beta-5-o-carboranyl-2'-deoxyuridine (CDU), compounds designed for boron neutron capture therapy (BNCT), were studied using human CEM lymphoblast and U-251 glioblastoma cells, at a physiologically achievable concentration (1 microM). Accumulation of the enantiomers was rapid and indistinguishable, reaching cellular concentrations > 40-fold higher than extracellular levels, with approximately 5% persisting in cells after incubation in fresh medium for more than 2 hr. Uptake was not affected by nucleoside uptake inhibitors, but was inhibited by the purine base uptake inhibitor papaverine.

[Extracorporeal membrane oxygenation in the treatment of severe pulmonary hypertension in a neonate after surgery for laparoschisis]. / Mimotelní membránová oxygenace v lécbe tezké plicní hypertenze u novorozence po operaci laparoschízy.

The authors describe the case of newborn with laparoschisis in whom severe idiopathic pulmonary hypertension during postoperative period developed and initiation of extracorporeal membrane oxygenation (ECMO) to maintain circulatory stability and adequate oxygenation was necessary. ECMO was performed for 75 hours with maximum extracorporeal support up to 50% of cardiac output (Biomedicus pump BP 50, Jostra oxygenator M8). Patient was successfully weaned and switched to conventional ventilation and nitric oxide inhalation with consequent extubation. No bleeding complications were observed during ECMO in connection with surgical repair of laparoschisis.

[Abdominal lymphangiomas in childhood]. / Abdominální lymfangiomy v detském veku.

The authors evaluate their experience with the diagnosis and treatment of abdominal lymphangiomas during the period of 1995-1999. During the above period 6 girls and 4 boys with abdominal lymphangiomas were operated. The mean age at the time of operation was 5 years and 8 months. Ultrasonographic examination was made in all 10 patients, CT examination in 8. The surgical finding was lymphangioma of the mesenterium 4x, of the omentum 2x, of the adrenals 2x of the retroperitoneum 1x and intestinal lymphangiomatosis 1x. Macroscopically complete extirpation of the lymphangioma was possible in 9 patients and called for resection of the gut 3x and for adrenalectomy 2x. In one patient subtotal extirpation was performed. Postoperative follow-up did not reveal a relapse in any of the children. Abdominal cystic lymphangiomas are rare benign malformations of the lymphatic system. For preoperative differential diagnosis in typical cases USG is sufficient. The therapeutic method is complete surgical extirpation which is associated with a low incidence of relapses.

[Ileus and intestinal perforation in premature infants--current trends in diagnosis and treatment]. / Ileus nedonosených a perforace streva--soucasné trendy v diagnostice a v lécbe.

OBJECTIVE OF STUDY: a) assessment of the relationship between ileus of premature infants and the development of intestinal perforation in premature infants, b) suggestions of an optimal therapeutic procedure. In the study children (n = 50) are included a) with intestinal perforation in conjunction with impaired excretion of meconium (n = 22), b) with an ileus state based on obstruction of the ileum by a viscous meconium treated either surgically or conservatively (n = 28). Surgical treatment involved: a) establishment of a double ileostomy (n = 28), b) insertion of a T drain into the terminal ileum (n = 8), c) removal of meconium from the gut and its primary closure (n = 2). Conservative treatment in 11 children involved irrigography with an liquid contrast substance under X-ray control. The group of children with perforation was compared with the group of children without perforation, risk factors were evaluated by statistical methods. The necessity of ventilation (P = 0.051) and gestation age (P = 0.006) proved to be statistically significant risk factors for the development of perforation. Survival was not influenced by perforation. All 11 children treated conservatively survived, of 39 operated children 26 survived (66.7%). An early start of conservative treatment of ileus of premature infants reduces markedly the risk of intestinal perforation and can thus influence the survival of low birth weight neonates.

Penetration of antibiotics into the pancreas in rats: an effect of acute necrotizing pancreatitis.

BACKGROUND: Penetration of antibiotics into the pancreas is considered to be an important criterion in determining the most appropriate antibiotic treatment during severe acute pancreatitis. Our study investigated pancreatic penetration of five antibiotics in rats with and without acute necrotizing pancreatitis (ANP) (non-pancreatitis rats (NR), pancreatitis rats (AP)). METHODS: ANP was induced by intraductal bile acid injection, and 3 h later the antibiotic was administered. In both NR and AP the antibiotic concentrations were evaluated in blood and pancreatic tissue 90 min after antibiotic administration. RESULTS: The tissue/serum (T/S) ratios for NR were 16% with amikacin, 24% with amoxycillin/clavulanic acid, 27% with piperacillin, 59% with ofloxacin, and 108% with cefoperazone. The ratios for AP were 7%, 23%, 26%, 52%, and 70%, respectively. T/S ratios were similar for NR and AP except for amikacin, for which the T/S ratio was lower in AP than in NR (P = 0.02). Pancreatic tissue concentrations of antibiotics with high penetration rates (cefoperazone and ofloxacin) were sufficient to inhibit most of the pathogens expected during acute pancreatitis. The concentrations of the other antibiotics were less than the minimal inhibitory concentrations (MIC) for common potential pathogens in pancreatic infection. CONCLUSIONS: Cefoperazone and ofloxacin showed the best pancreatic penetration of the five antibiotics tested. The high concentrations of these antibiotics in the pancreatic tissue would have enabled efficient antibacterial activity against most of the potential pathogens causing pancreatic infection. An early stage of acute necrotizing pancreatitis did not have a major effect on the pancreatic concentrations of the antibiotics.

Radioimmunoassay for quantitation of 2',3'-didehydro-3'-deoxythymidine (D4T) in human plasma.

2',3'-Didehydro-3'-deoxythymidine (D4T, or stavudine) has been recently approved for the treatment of AIDS. In the present study, a specific and sensitive radioimmunoassay (RIA) was developed for the quantitation of D4T in human plasma. The RIA is a double-antibody competitive binding assay which uses anti-D4T antiserum raised in rabbits as the primary antibody, a tritiated derivative of D4T as the radioactive tracer, and goat anti-rabbit immunoglobulin G as the secondary antibody. No cross-reaction between D4T and various nucleoside analogs was detected. The limit of quantitation of the method approximated 20 ng/ml. Replicate analyses of quality control samples (40 to 3,500 ng/ml) had satisfactory intra- and interassay precision (coefficient of variation, 1.7 to 16.7%) and accuracy (deviation, -9.5 to +21.0). This newly developed RIA was successfully used in the monitoring of plasma drug levels in healthy volunteers receiving an oral dose of D4T.

A structural basis for a phosphoramide mustard-induced DNA interstrand cross-link at 5'-d(GAC).

Phosphoramide mustard-induced DNA interstrand cross-links were studied both in vitro and by computer simulation. The local determinants for the formation of phosphoramide mustard-induced DNA interstrand cross-links were defined by using different pairs of synthetic oligonucleotide duplexes, each of which contained a single potentially cross-linkable site. Phosphoramide mustard was found to cross-link dG to dG at a 5'-d(GAC)-3'. The structural basis for the formation of this 1,3 cross-link was studied by molecular dynamics and quantum chemistry. Molecular dynamics indicated that the geometrical proximity of the binding sites also favored a 1,3 dG-to-dG linkage over a 1,2 dG-to-dG linkage in a 5'-d(GCC)-3' sequence. While the enthalpies of 1,2 and 1,3 mustard cross-linked DNA were found to be very close, a 1,3 structure was more flexible and may therefore be in a considerably higher entropic state.

Cellular pharmacology and biological activity of 5-carboranyl-2'-deoxyuridine.

PURPOSE: The intracellular uptake and metabolism of 5-carboranyl-2'-deoxyuridine was investigated in primary human lymphocytes and in a T lymphoblastoid cell line using unlabeled and tritium labeled compound. The cytotoxicity and antiviral activity of the compound and stability to enzyme degradation was determined. METHODS AND MATERIALS: A novel method for radiolabeling the 5-carboranyl moiety of pyrimidine nucleosides was developed. Cells were exposed to unlabeled and tritium labeled 5-carboranyl-2'-deoxyuridine and the intracellular uptake and egress of the compound determined by high pressure liquid chromatography. The viability and growth of normal and malignant cells, including human and rat gliomas, in the presence of the compound was determined. RESULTS: Substantial levels of 5-carboranyl-2'-deoxyuridine-5'-monophosphate are formed intracellularly and this major metabolite can be detected in cells 48 h after removal of the parent compound from the medium. No significant phosphorylation to the 5'-diphosphate or triphosphate of 5-carboranyl-2'-deoxyuridine was detected. Furthermore, radiolabeled 5-carboranyl-2'-deoxyuridine was not incorporated into deoxyribonucleic acid. 5-carboranyl-2'-deoxyuridine was essentially nontoxic to human lymphocytes as well as human or rat glioma cells, and had no marked effect in human lymphocytes acutely infected with human immunodeficiency virus type 1. CONCLUSION: The results demonstrate for the first time that 5-carboranyl-2'-deoxyuridine is phosphorylated intracellularly and suggest that it should be considered for further studies as a potential sensitizer for boron neutron capture therapy.

Nucleobase transporter-mediated permeation of 2',3'-dideoxyguanosine in human erythrocytes and human T-lymphoblastoid CCRF-CEM cells.

Several 2',3'-dideoxynucleosides (ddNs), agents that inhibit the replication of human immunodeficiency virus and hepatitis B virus, enter mammalian cells by simple diffusion. In this report, we show that the membrane permeation of 2',3'-dideoxyguanosine (ddG) in human erythrocytes and CCRF-CEM cells, in contrast with that of other ddNs, is transporter-mediated. Inward fluxes of ddG in both cell types were inhibited by adenine, hypoxanthine, and acyclovir, but not by inhibitors of nucleoside transport (nitrobenzylthioinosine, dipyridamole, dilazep). Fluxes of ddG in human erythrocytes were attributable to a single, rate-saturable process (Km, 380 +/- 90 microM and Vmax, 7.9 +/- 0.8 pmol/s/microliter cell water) that was competitively inhibited by adenine (Ki, 16 microM). These results showed that ddG entered human erythrocytes and CCRF-CEM cells by a transporter-mediated process that was also the basis for entry of purine nucleobases. In contrast, inward fluxes of 2,6-diaminopurine-2',3'-dideoxyriboside (ddDAPR), a prodrug of ddG, were not affected by purine nucleobases or nucleoside transport inhibitors in either cell type. Thus, the permeation properties of ddDAPR resembled those of 2',3'-dideoxyadenosine, a diffusional permeant (cell uptake is transporter-independent), and contrasted with those of ddG, the deamination product of ddDAPR. This study demonstrated that the nucleobase moiety of ddNs is an important determinant of membrane permeation.

Changes of lithium elimination in acute polyuric renal failure caused by cisplatin and mercuric chloride.

Changes in lithium elimination were studied under the condition of experimentally induced polyuric acute renal failure by cisplatin (6 mg/kg body wt) or HgCl2 (3 mg/kg body wt). The histologically proven lesions of tubuli were associated with the decrease of plasma clearance of lithium (C(Li)) and polyfructosan-S (CP(FS). The decrease of these clearance values was not proportional and the ratio C(Li)/CP(FS) (indicating renal fractional excretion of Li+) increased significantly (p less than 0.01). The increase of C(Li)/CP(FS) was related to the increase of renal fractional sodium excretion (FENa) (p less than 0.01). The results suggest that the impairment of tubular cells by cisplatin or HgCl2 caused the decrease of tubular reabsorption of Li+ and Na+. From the pharmacokinetic point of view, these experiments suggest that changes in tubular transport of drugs should be taken into account in their dosing adjustment in patients with acute polyuric tubular lesion.

[Abnormal placement of the testes]. / Polohové anomálie varlat.

The authors defined a uniform classification of abnormal positions of the testes. They recommend also a uniform therapeutic procedure: after the first year of life treatment with human chorionic gonadotropin in one or two curves, if orchiopexy fails.

Pharmacokinetics of roxithromycin in kidney grafted patients under cyclosporin A or azathioprine immunosuppression and in healthy volunteers.

The pharmacokinetics of roxithromycin was studied in 9 kidney grafted patients under cyclosporin A immunosuppression, in 10 transplanted patients with azathioprine, and in 6 healthy volunteers. The biological half-life (beta-phase) of roxithromycin in cyclosporin patients was 34.4 (+/- 12.25) h (mean +/- SD), in azathioprine patients 23.4 (+/- 8.18) h and in healthy volunteers 17.0 (+/- 3.8) h. The total elimination constant (k10) was 0.046 (+/- 0.014), 0.068 (+/- 0.019) and 0.084 (+/- 0.036) h, respectively. The total clearance was 0.79 (+/- 0.21), 1.45 (+/- 0.66) and 1.84 (+/- 0.56) l/h, respectively. The areas under the serum level curves were 407.6 (+/- 118.3), 251.0 (+/- 106.6) and 180.7 (+/- 73.2) mg.h/l, respectively. The differences in these parameters between healthy volunteers and cyclosporin patients were statistically significant, as well as those between cyclosporin and azathioprine patients. The differences between healthy volunteers and azathioprine patients were not statistically significant. The results cannot be interpreted unambiguously as an interaction between roxithromycin and cyclosporin; the effect of cyclosporin on the function of eliminating organs which causes the slowed-down elimination of roxithromycin could be taken into account.

[Why is peroperative antibiotic prophylaxis of infectious complications most effective?]. / Proc je peroperacní antibiotická profylaxe infekcních komplikací nejúcinnejsí?

The concentrations of oxacillin, azlocillin, temocillin, amoxycillin, cefoperazone, cefazoline, netilmicin, clindamicin, ofloxacine in serum and coagulum take a parallel course but their content in the coagulum is ten times lower than in serum--with the exception of doxycycline which reached a 40% value of the serum level in the coagulum. From this ensues that most effective are those antibiotics which can be administered in large doses and which have a long half-life. Unfavourable are antibiotics with a narrow therapeutic range and those with a short half-life. Preoperative application of such doses which create sufficiently high and prolonged levels is the optimal method of antibiotic prophylaxis of infectious complications during surgical operations.