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Despite the variety of modern molecular techniques available, examination of foetal anatomy is still a fundamental part of teratological studies in evaluating the developmental toxicity of xenobiotics or other non-chemical factors. The article presents contemporary methods of embryotoxicity and foetotoxicity assessment. A single alizarin red S and double alcian blue followed by alizarin red S staining, as well as various methods of soft tissue examination are discussed. [ABSTRACT FROM AUTHOR]

Tumor necrosis factor type alpha (TNF-alpha) is one of 22 TNF superfamily ligands. Its synthesis is regulated by expression of gene localized on chromosome 6. During posttranslation modification the proteolytic cleavage of the 76-aminoacid domain from the membrane-bound protein occurs with final formation of mature, biologically active, secreted TNF-alpha form. The effect on the target cells depends on the activation of specific surface receptors: TNFR1--is present on most nuclear cells and has affinity to both membrane-bound and secreted forms; TNFR2--is localized mostly on fibroblasts, endothelial cells, lymphocytes, macrophages, neutrophils and thymocytes, and is activated almost selectively by membrane-bound form. Depends on additional factors the TNFR1 activation may initiate apoptosis, or activation of pathways which depend on nuclear factor kappaB (NFkappaB) and c-Jun N-terminal kinase (JNK). Role of TNFR2 is unclear. TNF-a has multidirectional biological activity that include immunomodulation, oncostatic, osteolytic, pirogenic, proinflammatory and other effects.

Wilson's principles were formulated after thalidomide tragedy. They become a fundamental for teratological studies with drugs and other factors that may disturb fetal development. It is postulated that susceptibility to teratogen depends on the genotype and developmental stage of the conceptus. Teratogenic agents act in specific manner on developing cells and tissues. The exposition depends on the agent's nature and availability. Manifestations of deviant development depends on the dosage and exposure frequency. In case of abnormal development the final manifestations include death of embryo or fetus, malformation, growth retardation and functional disorder.

Metabolic acidosis severely complicates methanol and ethylene glycol intoxications. Acidosis is caused by acid metabolites and can be intensified by lactate elevation. Lactate concentration depends on the NADH(2)/NAD ratio. Lactate dehydrogenase (LDH, E.C.1.1.1.27.) supplies more lactate when the level of NADH(2) is elevated. The aim of the study was to evaluate the effect of alcohol dehydrogenase (ADH) inhibitors and substrates: cimetidine, EDTA, 4-methylpyrazole (4-MP), Ukrain and ethanol on LDH activity. The activity of LDH was determined spectrophotometrically in human liver homogenates incubated with cimetidine, EDTA, 4-MP and Ukrain at concentrations of 2 x 10(-6), 10(-5) and 5 x 10(-5) m as well as ethanol at concentrations of 12.50, 25.00, 50.00 mm. The LDH activity was significantly increased by 10(-5) and 5 x 10(-5) m concentrations of cimetidine and 4-MP, and by all concentrations of ethanol. The most effective change of LDH activity of about 26% (P<0.01) was observed at the highest concentration of ethanol. Ukrain inhibited LDH activity at both concentrations, i.e. 10(-5) and 5 x 10(-5) m (P<0.05). However, EDTA did not significantly influence LDH activity. The data showed that ethanol and 4-MP, the main antidotes in methanol or ethylene glycol poisoning, may increase liver LDH activity - an undesirable effect during the therapy of patients intoxicated with these alcohols. On the other hand, the decrease of LDH activity in the presence of Ukrain is a promising finding but definitely requires further investigation., (Copyright (c) 2005 John Wiley & Sons, Ltd.)

Slow, time-dependent, irreversible, highly selective inhibitors of COX-2 such as celecoxib, etoricoxib, rofecoxib and valdecoxib, so-called coxibs, are a new group of drugs widely used in rheumatology as well as in other fields of medicine. The tolerability of these drugs is at least equivalent to that of commonly used non-selective COX inhibitors (e.g. diclofenac, ibuprofen, naproxen). The unquestionable superiority of selective COX-2 blockade includes a low risk of gastrointestinal side effects. However, similarly to the other COX inhibitors, coxibs must be carefully administered to patients with coexistent liver and renal disease, generalised atherosclerosis, ischaemic heart disease, and to the elderly and children. Pregnancy and lactation require precise monitoring of adverse effects on the fetus, neonate and infant, or discontinuation of therapy with the drug.

Unlabelled: Although more and more is known about chronic autoimmune diseases, attempts to establish one trigger factor have been unsuccessful. The role of endogenic factors is beyond doubt. But it is emphasized that environmental factors are necessary to cause the disease. Infections are taken under consideration as trigger mechanism in the development of autoimmune diseases including chronic arthritis. Both numerous viruses and bacteria are among the microorganism mentioned. We considered it sensible to conduct research on Mycoplasma pneumoniae infections in a group of patients with juvenile idiopathic arthritis (JIA)., Materials: 19 patients diagnosed with JIA aged between 6-17 were investigated for Mycoplasma pneumoniae infection whose blood was examined for antibodies against Mycoplasma pneumoniae in class IgG and IgM. The control group comprised 20 children of similar age admitted to hospital with digestive tract complaints., Methods: Serologic tests were made in serum. Marking of antigens of class IgM and IgG were made by Elisa method using commercial kits produced by Scientific Point. Quantitative calculations of a level of antigens were done using appropriate standards, positive and negative serum of reference standard and calibration curve., Results: In 11 patients positive reaction for Mycoplasma pneumoniae in class IgG was observed and only in 2 in class IgM with low titer. In the control group positive reaction was observed in 3 children (15%). The fact that 58% of patients were infected (contact either with Mycoplasma pneumoniae) indicates that in the group of our patients with JIA, infections with these bacteria might have had a role in triggering the disease.

Slow, time-dependent, irreversible, highly selective inhibitors of COX-2 (coxibs) have been used for the treatment of osteoarthritis and rheumatoid arthritis, as well as other disease entities such as acute pain, fever, neoplastic changes, and Alzheimer's disease, the pathomechanism of which is dependent on the coexisting inflammatory process or overexpression of cyclo-oxygenase (COX) genes. The article presents current state of knowledge about the clinical efficacy of coxibs (celecoxib, rofecoxib) compared to non-selective COX inhibitors. The physiology and pathophysiology of both COX isoforms (COX-1, COX-2) are also discussed.

Relapsing polychondritis is a very rare disease of the connective tissue in children. Inflammation may affect all cartilaginous structures. The study presents the case of a 10 years old boy with bilateral conchitis as a prominent symptom of the disease. In our patient lower airways were seriously affected. The detection of the degree of the disease in respiratory tract was facilitated to a large degree by pulmonary function tests and high resolution computed tomography. Histopathological picture of the inflamed cartilage of the tracheobronchial tree finally confirmed the diagnosis.