Comparison of the cell immunophenotype of metastatic and primary foci in stage IV-S neuroblastoma

Neuroblastoma represents one of the most frequently developing malignant solid tumours in children. At the time of diagnosis, in more than half of the cases, metastatic cells are also present in the bone marrow. The present study was aimed at immunocytochemical analysis of selected neuropeptide manifestation in metastatic cells of neuroblastoma in bone marrow and at comparing the obtained results with the immunophenotype of parental neuroblastoma cells. The studies were performed on bone marrow material obtained from children treated at the Department of Paediatric Haematology and Oncology, University of Medical Sciences, Poznań, Poland, in 1998-2000. Immunocytochemical analysis of nervous tissue markers (employing the immunomax technique) involved 36 bone marrow preparations obtained from 27 children. The analysis included expression of neuron-specific enolase (NSE), PGP 9.5 protein, substance P (SP), chromogranin A (ChA), bombesin (B), galanin (G), neuropeptide Y (NPY) and vasoactive intestinal peptide (VIP). Close to 90% metastatic cells in bone marrow were found to exhibit NSE+SP+B+ phenotype and over a half of the cells manifested additionally expression of PGP 9.5+ChA+NPY+. Comparison of the obtained results with the immunophenotype of neuroblastoma cells obtained directly from the primary tumour demonstrated high correlation of NSE, SP and PGP 9.5 expression. Due to the relative ease of obtaining the bone marrow material and absence of neuromarkers in bone marrow metastatic cells in solid tumours other than neuroblastoma, determination of immunophenotype of the cells may represent a valuable supplementation in preliminary diagnosis of this tumour in children.     

Influence of 4-day long treatment with vasoactive intestinal peptide on ultrastructure and function of the rat pinealocytes in organ culture

Vasoactive intestinal peptide (VIP) is one of neuropeptides involved in the regulation of the pineal gland function. The acute treatment of rat pinealocytes with VIP caused changes in their biochemical parameters. The present study concerns the effects of the chronic treatment with VIP on ultrastructure and function of the rat pinealocytes in organ culture. The pineals of adult male rats were assigned to one of three groups and placed in organ culture for four consecutive days. The pineals of the first group were incubated in the control medium, the pineals of the second group--12 hrs in control medium and 12 hrs in medium with 1 microM VIP (between 20.00 and 8.00) during each day, the pineals of the third group--24 hrs per day in medium with 1 microM VIP. The melatonin concentration was measured using RIA and activity of enzymes using radiochemical methods. Point count method was used in quantitative ultrastructural analysis. Both modes of chronic treatment with VIP increased significantly the level of melatonin secretion during four days of the culture and the content of this hormone in the pineal explants at the end of the experiment. Treatment with the neuropeptide for 12 hrs and 24 hrs per day elevated also the activity of arylalkylamine N-acetyltransferase and hydroxyindole-O-methyltransferase. On the other hand, VIP had no effect on the activity of arylamine-N-acetyltransferase. VIP increased the relative volume of rough endoplasmic reticulum, Golgi apparatus and mitochondria and did not influence the relative volume of lysosomes and lipid droplets as well as the numerical density of dense core vesicles in the examined rat pinealocytes. The obtained results indicate stimulatory effect of chronic treatment with VIP on the synthesis and secretion of melatonin in the rat pinealocytes in vitro. The results of morphological study are in agreement with the obtained biochemical data and point to the increase in secretory and metabolic activity of the rat pinealocytes in response to VIP.     

Application of Mitsunobu reaction to solid-phase peptide nucleic acid (PNA) monomer synthesis

PNA type I monomer backbone with a reduced peptide bond was synthesized on a Merrifield resin in Mitsunobu reaction of Boc-aminoethanol with resin-bound o-nitrobenzenesulfonylglycine. The pseudodipeptide secondary amine group was deprotected by thiolysis and acylated with thymin-1-ylacetic acid. The monomer was released as a methyl ester. The procedure seems to be of general applicability and allows various modifications of PNA structure by using diverse alcohols and amino acid esters.     

Circadian rhythm characteristics of serum cortisol and dehydroepiandrosterone sulfate in healthy Chinese men aged 30 to 60 years. A cross-sectional study

The relation of adrenal function and aging has been the subject of intense interest in recent years. The circadian variations of plasma cortisol have been described in Caucasians, but little information is available on such hormone variations among the Chinese population, especially its changes with age. This study was, therefore, designed to examine the effects of age on the circadian variations of serum cortisol, dehydroepiandrosterone sulfate (DHEAS) and the molar ratio of cortisol/DHEAS in Chinese men, stratified by 10-year age-groups (i.e. men in their 30-60s, aged from 31 to 63 years old). Circadian variations of serum cortisol and DHEAS were documented at 2-h intervals from 8:00 to 22:00 and hourly from 22:00 to 8:00 in 26 healthy Chinese men. We found that the serum levels of both hormones showed a statistically significant circadian rhythmicity in all age-groups. The circadian pattern of serum cortisol was characterized by peaks (04:00-06:00) and troughs (18:00-24:00) occurring approximately 2h earlier than those usually reported in Caucasians. Aging did not significantly influence serum cortisol concentrations, but serum DHEAS levels declined significantly with age: subjects in their 60s had significantly lower levels, and their cortisol/DHEAS molar ratios were significantly higher than those in the younger age-groups.     

Kette regulates actin dynamics and genetically interacts with Wave and Wasp

During development of the Drosophila nervous system, kette is required for axonal growth and pathfinding. It encodes a highly conserved homolog of the Nck-associated protein 1 (NAP1) that genetically interacts with the Drosophila homolog of Nck, dock. We show that in vivo as well as in tissue culture models most of the Kette protein is found in the cytoplasm where it colocalizes with F-actin to which it can bind via its N-terminal domain. Some Kette protein is localized at the membrane and accumulates at focal contact sites. Loss of Kette protein results in the accumulation of cytosolic F-actin. The kette mutant phenotype can be suppressed by reducing the wave gene dose, demonstrating that kette antagonizes wave function. Overexpression of the wild-type Kette protein does not interfere with normal development, whereas expression of an activated, membrane-tethered Kette protein induces the formation of large F-actin bundles in both, tissue culture cells and in vivo. This gain-of-function phenotype is independent of wave but can be suppressed by reducing the wasp gene dose, indicating that Kette is able to regulate Wasp, to which it is linked via the Abelson interactor (Abi). Our data suggest a model where Kette fulfils a novel role in regulating F-actin organization by antagonizing Wave and activating Wasp-dependent actin polymerization.     

Biochemical characterization of aeromonad strains differing in pathogenicity

A virulent strain of motile aeromonad (77-18) and an avirulent strain (78-16) differed in the contents of lipids and phospholipids, odd fatty acids, activity of hydrolytic enzymes, and amount of proteins with molecular weights of 47-56 kDa. It is assumed that proteins with molecular weights of 47-56 kDa, proteolytic enzymes active within a wide pH range, and odd fatty acids may act as pathogenicity factors. Each of these compounds or their combination determines certain stage of infection.     

Expression of the Na(+)/I(-) symporter in invasive ductal breast cancer

The function of the sodium iodide symporter (Na(+)/I(-), (NIS), a membrane protein that mediates iodide transport into cells, is the best described in the thyroid cells. NIS is also found in mammary cells during lactation and in breast carcinoma cells. The aim of this study was evaluation of incidence and grade of NIS expression in invasive ductal breast cancer. Immunohistochemistry using a panel of antibodies against NIS was carried out in surgical paraffin-embedded tissue obtained from 50 patients with invasive ductal breast carcinoma. NIS expression was found in 45 (90%) cases. The demonstration of NIS expression in breast carcinoma cells may provide a novel approach to its diagnosis and treatment.     

Pivotal participation of nitrogen dioxide in L-arginine induced acute necrotizing pancreatitis: protective role of superoxide scavenger 4-OH-TEMPO

For the first time, a direct sensitive method of *NO(2) detection and measurement in biological material has been established. It is based on the interaction of this radical with the coordination compound of Cr(III) with aminodeoxysugar as biosensor. Our new method makes it possible to precisely assess *NO(2) level in experimental acute necrotizing pancreatitis induced by L-arginine, where oxidative and nitrosative stresses are supposed to play a key role in the pathomechanism of the disease. As much as 20 nmol of *NO(2)/mg protein was detected which correlated with severe deterioration of pancreatic acinar cell ultrastructure. Protective effect of superoxide radical scavenger 4-OH-TEMPO expressed as *NO(2) level decrease confirmed by preserved acinar cell ultrastructure and decreased pancreatic amylase release to blood serum is demonstrated. This study reveals a possible pathomechanism of L-arginine induced acute pancreatitis.     

Adaptation of PCR technique for quantitative estimation of genetic material from different regions of chromosome 21 in cases of trisomy 21

Pre- and postnatal diagnosis of chromosomal aberrations is generally based on conventional cytogenetic analysis. In this paper, we have devised a quantitative polymerase chain reaction (Q-PCR) method to determine gene dose effects and applied it in cases of regular trisomy 21 as a model. The method is based on quantitative assessment of PCR products after using primers amplifying DNA fragments located in the pericentromeric, heterochromatic, euchromatic and telomeric regions of chromosome 21. A gene dose effect on the amount of PCR product in cases of trisomy 21 was confirmed. Moreover, a correlation between the amount of the PCR product of the examined sequences and their location in the chromosome was observed. The obtained results suggest that the Q-PCR technique can be applied in the diagnosis of aneuploidies.