[Neuroendocrine tumours of the upper gastrointestinal tract, characteristics and comparison of localization diagnostics]. / Neuroendokrinné nádory horného tráviaceho traktu, charakteristika a porovnanie efektivity lokalizacnej diagnostiky.

In daily clinical practice it's important to think of neuroendocrine tumors, since their prevalence for the past 5 years exceeded even the common occurrences of stomach, esophageal and pancreatic cancers. Patients diagnosed early and accurately with NET, have a greater chance for complete cure. The diagnostic tools over the past century were significantly inefficient in diagnosing NET i.e. (40% of tumors were not localized after USG, CT, MRI, AG investigations). Until the past 2 decades that major turnover in diagnostic methods has been achieved. In particular, the introduction of the somatostatine receptor scintigrafy (SRS) and endoscopic ultrasonography (EUS) have increased sensitivity of localization diagnostics up to 90%. Our work is to test the success of the localization diagnostics in 22 patients with surgically and histologically confirmed NET ofthe pancreas and duodenum. These patients fulfilled jointly SRS, CT and/or MRI, but also classic USG and EUS. From our comparison, clearly endoscopic USG is the most efficient tool with 90% sensitivity.

Suppression of the avian sarcoma virus genome in 8-azaquanine-resistant, transformed, hamster cells.

The avian sarcoma virus genome (Schmidt-Ruppin strain) in transformed hamster cells resistant to 8-azaquanine [Ha(SR)AG-50] was strongly suppressed. The suppression was genetically stable and could not be overcome by attempts at induction with 5-iodo-2'-deoxyuridine. Fusion of hamster cells, which had suppressed virus genome, with chicken Rous-associated virus (RAV-1)-preinfected cells easily rescued the sarcoma virus. The rescued virus had envelope properties of RAV-1, as determined by viral interference, virus neutralization, and plating on genetically resistant chicken cells. By repeatedly cloning the rescued virus, we determined that virus recombined in the rescue experiment and that the recombinant virus had the envelope properties of helper virus used for its rescue. Cells with suppressed avian sarcoma virus genome were suitable for preparation of different recombinant viruses.

Mouse MSV transformed cells resistant to 8-azaguanine.

Mouse cells transformed by murine sarcoma virus were made resistant to 8-azaguanine. Resistant cells and cell clones isolated from them were deficient in hypoxanthine-guanine phosphoribosyl transferase (HGPRT) activity. They did not grow in HATG medium, did not incorporate labeled hypoxanthine, and had negligible HGPRT activity. The resistance was genetically stable. The resistant cells were hyperdiploid and contained telocentric chromosomes only. The resistant cells as well as the progenitor cells were slightly tumorigenic in mice, the plating efficiency in soft agar was very low. The parental cells and aza-G resistant cells produced C-type viral particles having RNA-dependent DNA polymerase activity. The resistance to aza-G did not influenced the expression of murine sarcoma virus genome in cells. The resistant cells are suitable for preparation of cell hybrids.

Infection of human embryo cells with avian sarcoma virus B77 in vitro.

Human embryo cells were infected with avian sarcoma virus B77--Hu(B77). The virus genome was detected in the Hu(B77) cells during subsequent cell passages in the uncloned cells as well as in single-cell clones. Despite the presence of the virus genome in cells, the growth properties did not differ from uninfected cells. The Hu(B77) cells did not reveal the transformed phenotype in vitro.

Early and delayed auditory oddball ERPs and brain MRI in patients with MTBI.

INTRODUCTION: Mild traumatic brain injury (MTBI) is a common neurotraumatologic diagnosis. It is possible to confirm objective cognitive impairment in MTBI patients not only by complex neuropsychological testing but also by event-related potentials (ERPs). The most common ERPs used in clinical practice are based on an oddball paradigm. Magnetic resonance imaging (MRI) is not routinely used in MTBI despite its proven greater sensitivity and specificity in comparison with computer tomography (CT). METHODS: This study investigated 31 MTBI patients and 31 sex and age-matched healthy controls. Both groups underwent clinical neurological examinations. Auditory oddball ERPs and brain MRI were done early after the injury and 3-7 months later. RESULTS: There were no significant sex, age and education differences between the analysed groups. No significant differences were found in N2 and P3 wave parameters in both ERP examinations. CONCLUSION: Standard auditory oddball ERPs are not sensitive enough to detect and/or quantify subtle objective neuropsychological changes in selected MTBI patients, especially those with traumatic MRI brain lesions. More complex auditory or other oddball paradigms have to be tested in the future.

Electrophoretic karyotype of Dipodascus (Endomyces) magnusii: two main intraspecific chromosomal polymorphisms associated with the difference in total genome size.

This study describes the karyotype of strain 270 of the yeast-like fungus Endomyces magnusii. It consists of 13 chromosomal DNA molecules, the size of which range between 1.2 and 5.7Mb producing a genome size of approximately 38Mb. By comparing the karyotype of six strains of E. magnusii, we revealed two main chromosome length polymorphisms (CLPs) associated with a pronounced difference in the total genome size (roughly 50%). Karyotype heterogeneity between two main CLPs was demonstrated by Southern analysis with three heterologous probes. The same species affiliation of six E. magnusii strains was confirmed by morphological and cytological studies, protein fingerprint comparisons, as well as restriction analysis of mitochondrial DNA and genomic Southern analysis.