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Evidence of recurrent atypical meningioma with rhabdoid transformation and expression of pyrogenic cytokines in a child presenting with a marked acute-phase response: case report and review of the literature.

Children presenting with acute systemic illnesses that lack specific clinical or serological defining features may be diagnosed as having a chronic infection, an atypical systemic vasculitis or a connective tissue disease, but often turn out to have occult neoplasias. Cytokines have been implicated in causing many of the systemic effects in such cases. In this study, we describe the case of a 9-year-old boy presenting at an interval of 18 months with a marked acute-phase response due to a recurrent atypical meningioma with rhabdoid transformation of the tentorium cerebelli. Resection of the recurrent tumor was curative. We evaluated in detail the local and systemic production of cytokines released by the primary and the recurrent tumor. Blood and CSF samples were taken pre-, intra-, and postoperatively, and the production of IL-6, IL-1beta, and TNF-alpha was measured by enzyme-linked immunosorbent assays (ELISA). The level of IL-6 in CSF was about 150-fold increased before tumor resection, normalizing postoperatively. On the contrary, the levels of IL-1beta and TNF-alpha in CSF and of IL-6, IL-1beta, and TNF-alpha in serum were pre-, intra-, and postoperatively within normal limits. Cytokine production was also evaluated immunohistochemically, and confirmed strong IL-6 and TNF-alpha expression in the primary and the recurrent tumor, while expression of IL-1beta was lacking. The scattered MHC class II- and leukocyte common antigen (LCA)-expressing inflammatory cells, which were infiltrating exclusively the tumoral stroma, had no detectable cytokine immunoreactivity. We conclude that chronic IL-6 and TNF-alpha production by the tumor cells in this patient was responsible for the severe systemic illness with which he presented.

Acute Disease↗

Mechanisms and sites of pyrogenic action exerted by staphylococcal enterotoxin A in rabbits.

The febrile responses induced by i.v. administrations of staphylococcal enterotoxin A (SEA) was mimicked by direct injection of SEA into the organum vasculosum laminae terminalis (OVLT) in unanesthetized rabbits. Compared with the febrile responses induced by i.v. injection of SEA, the OVLT route of injection required a much lower dose of SEA to produce a similar fever. Furthermore, the fever induced by intra-OVLT or i.v. injection of SEA was significantly attenuated by pretreatment with intra-OVLT injection of anisomycin (a protein synthesis inhibitor), indomethacin or diclofenac (inhibitors of cyclo-oxygenase (COX)), and aminoguanidine or dexamethasone (inhibitors of inducible nitric oxide synthase (iNOS)). These results suggest that COX or iNOS pathway in the OVLT mediate the SEA-induced fever in rabbits.

Animals↗

High-performance affinity capture-removal of bacterial pyrogen from solutions.

Synthetic peptide S3delta has high affinity for bacterial endotoxin or lipopolysaccharide (LPS). Under tested conditions of pH 5-9 and 0-0.4 M NaCl, the affinity constant, KD ranged from 2.10(-6) to 2 x 10(-9) M(-1). A novel affinity matrix based on peptide S3delta was developed for removal of LPS from solutions such as: water; buffers with a wide range of ionic strength and pH; medium for cell culture; and protein solutions under optimized conditions. At a starting LPS of approximately 100 EU/ml, a post-purification level below 0.005 EU/ml was achieved.

Amino Acid Sequence↗

Independent effects of the pineal and a bacterial pyrogen in behavioural thermoregulation in lizards.

The pineal complex of lizards is comprised of an extracranial photoreceptive structure known as the parietal eye, and an intracranial pineal organ which is homologous to the pineal gland of birds and mammals. Studies have shown that removing the parietal eye or severing the parietal nerve causes lizards to select higher temperatures when allowed to thermoregulate behaviourally in thermal or photothermal laboratory gradients. Although comparable studies involving removal of the lizard pineal organ have not previously been attempted, field data indicate that pinealectomy may have an antagonistic effect to parietalectomy. We present evidence here which shows that (1) following pinealectomy, collared lizards (Crotaphytus collaris) behaviourally select or prefer lower temperatures than their controls in thermal laboratory gradients, and (2) the effect of surgical treatment is independent of the effects of a behavioural fever-inducing substance which elevates by a fixed amount the environmental temperatures selected.

Animals↗