Abstract. Cryptdin mRNA codes for the apparent precursor to a corticostatin/defensin-related peptide that accumulates to high levels in mouse intestinal crypt epithelium during postnatal development. The primary structure, intestinal cell distribution, and developmental appearance of cryptdin mRNA have been determined. Cryptdin mRNA is 450-480 nucleotides long. Translation of the partial cryptdin cDNA sequence reveals a 70-amino acid open reading frame that includes 32 carboxy-terminal residues that align with those in the consensus sequence,

A member of the novel protein kinase C (PKC) subfamily, PKC, is an essential component of the T cell synapse and is required for optimal T cell activation and interleukin-2 production. Selective involvement of PKC in TCR signaling makes this enzyme an attractive therapeutic target in T cell-mediated disease processes. In this report we describe the crystal structure of the catalytic domain of PKC at 2.0-Å resolution. Human recombinant PKC kinase domain was expressed in bacteria as catalytically active phosphorylated enzyme and co-crystallized with its subnanomolar, ATP site inhibitor staurosporine. The structure follows the classic bilobal kinase fold and shows the enzyme in its active conformation and phosphorylated state. Inhibitory interactions between conserved features of staurosporine and the ATP-binding cleft are accompanied by closing of the glycine-rich loop, which also maintains an inhibitory arrangement by blocking the phosphate recognition subsite. The two major phosphorylation sites, Thr-538 in the activation loop and Ser-695 in the hydrophobic motif, are both occupied in the structure, playing key roles in stabilizing active conformation of the enzyme and indicative of PKC autocatalytic phosphorylation and activation during bacterial expression. The PKC-staurosporine complex represents the first kinase domain crystal structure of any PKC isotypes to be determined and as such should provide valuable insight into PKC specificity and into rational drug design strategies for PKC selective leads. Inhibitors of PKC1 are currently being used in clinical trials for various types of cancer, and a PKC␤ inhibitor is being used in clinical trials for diabetes-related retinopathy (1).PKC and PKB/AKT kinase domains are related by sequence homology; however, there are key structural differences in the regulatory domains and second messenger cofactor requirements. PKB/AKT contains an N-terminal pleckstrin homology domain regulated by phosphoinositide second messengers, a central catalytic kinase domain, and a C-terminal regulatory region facilitating key protein-protein interactions with signal-

Summary:Purpose: To study the markers of bone turnover in epilepsy patients in the different stages of the pubertal growth before and after the beginning of carbamazepine (CBZ) monotherapy.Methods: We have investigated bone turnover in 60 epilepsy patients treated with CBZ. They were stratified according to pubertal stage and compared with a control group of 60 sexand age-matched healthy children.Results: After 2 years of therapy, we found higher values of the serum markers of bone formation [bone alkaline phosphatase (bone ALP), osteocalcin (OC), carboxy-terminal propeptide of type I procollagen (PICP), amino-terminal propeptide of type III procollagen (PIIINP)], and of bone resorption [carboxy-terminal telopeptide of type I collagen (ICTP) and the urinary cross-linked N-telopeptides of type I collagen (NTX)] in patients than in control subjects, in presence of a normal vitamin D metabolism.Conclusions: CBZ induces an increase of bone formation and of bone resorption that seems to be independent of the pubertal stage. Key Words: Bone metabolism-CarbamazepineEpilepsy patients-Vitamin D-Pubertal stage.In recent years, many reports of altered calcium, vitamin D, and bone metabolism associated with anticonvulsant therapy have been published (1-5), but the results of these studies are conflicting. Recently some biochemical markers have been proposed to provide information about the dynamics of bone turnover. In particular, the markers of bone formation are osteocalcin (OC) or bone ␥-carboxyglutamic acid protein, noncollagenous protein of the bone matrix secreted by osteoblasts; circulating peptides of type I collagen, like the carboxy-terminal propeptide of type I procollagen (PICP) (6); and aminoterminal propeptide of type III procollagen (PIIINP), which reflects the rate of collagen type III synthesis (7). Among the markers of bone resorption, there are the serum cross-linked carboxy-terminal telopeptide of type I collagen (ICTP) and the urinary cross-linked N-telopeptides of type I collagen (NTX), which are the degraded products from osteoclastic activity (8). The aims of the study were to evaluate, prospectively, whether and to what extent differences exist in bone metabolism in prepubertal, pubertal, and postpubertal patients receiving CBZ in comparison to healthy controls and to determine the possible relations between these parameters and CBZ dosage and its serum concentration. MATERIALS AND METHODSWe studied 60 children with new onset of idiopathic partial seizures; their age ranged from 6.5 to 19.0 years. These patients were subdivided in three groups according to their pubertal stage: 20 (10 boys and 10 girls) prepubertal children (Ph1G1 and Ph1B1, respectively), 20 (10 boys and 10 girls) pubertal children (Ph2G2-Ph4G4 and Ph2B2-Ph4B4, respectively), and 20 (10 boys and 10 girls) postpubertal children (Ph4G4-Ph5G5 and Ph4B4-Ph5B5, respectively).The stage of sexual development was evaluated according to Tanner classification (9).Patients were recruited from the

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The authors studied 40 epileptic patients treated with valproate and 40 healthy controls for at least 2 years. At the end of follow-up, 15 epileptic patients (37.5%) had development of obesity. They showed circulating leptin and insulin levels significantly higher and ghrelin and adiponectin levels significantly lower than those of patients who did not gain weight.

We have studied the influence of periplasmic Cu,Zn superoxide dismutase on the intracellular survival of Escherichia coli strains able to invade epithelial cells by the expression of the inv gene from Yersinia pseudotuberculosis but unable to multiply intracellularly. Intracellular viability assays, confirmed by electron microscopy observations, showed that invasive strains of E. coli engineered to increase Cu,Zn superoxide dismutase production are much more resistant to intracellular killing than strains containing only the chromosomal sodC copy. However, we have found only a slight difference in survival within HeLa cells between a sodC-null mutant and its isogenic wild-type strain. Such a small difference in survival correlates with the very low expression of this enzyme in the wild-type strain. We have also observed that acid-and oxidative stress-sensitive E. coli HB101(pRI203) is more rapidly killed in epithelial cells than E. coli GC4468(pRI203). The high mortality of E. coli HB101(pRI203), independent of the acidification of the endosome, is abolished by the overexpression of sodC. Our data suggest that oxyradicals are involved in the mechanisms of bacterial killing within epithelial cells and that high-level production of periplasmic Cu,Zn superoxide dismutase provides bacteria with an effective protection against oxidative damage. We propose that Cu,Zn superoxide dismutase could offer an important selective advantage in survival within host cells to bacteria expressing high levels of this enzyme.Until a few years ago Cu,Zn superoxide dismutase (Cu, ZnSOD) was considered almost exclusively a eukaryotic enzyme, protecting the cytosol and the extracellular environment of higher organisms from damage by oxygen free radicals (1). Recently, Cu,ZnSOD has been identified in the periplasmic space of a wide range of gram-negative bacteria, including Brucella abortus (6), Haemophilus spp., Actinobacillus spp., Pasteurella spp., Neisseria meningitidis (24-26), Escherichia coli K-12 (7), Legionella pneumophila (40), Salmonella spp. (9), and Mycobacterium tuberculosis (45). This enzyme is thought to protect bacteria from toxic oxygen-free radicals generated outside the cell or in the periplasm itself, since superoxide is unable to cross the cytoplasmic membrane (21). Therefore, Cu,ZnSOD has been proposed to be a determinant of virulence in bacteria potentially exposed to toxic free radicals produced by the host in response to bacterial infection. In vivo experiments have demonstrated the role of bacterial Cu,ZnSOD in the virulence and pathogenicity of infecting microorganisms (15,18,19,36,42,43), while in vitro models have provided conflicting data concerning Cu,ZnSOD involvement in bacterial resistance to macrophage killing (19, 42) or survival within nonprofessional phagocytes (42). However, more recent results have shown that this enzyme protects Salmonella enterica serovar Typhimurium (15) and an overproducing strain of E. coli (4) from macrophage killing and that neutropenia restores virulence to an attenuated C...

Human dermal fibroblasts suspended in a collagen matrix exhibit a 4-day delay in cell division, while the same cells in monolayer divided by day 1. The initial rates of 3H-thymidine incorporation by cells in monolayer or suspended in collagen were not significantly different. When suspended in collagen, there was a threefold increase in the proportion of cells in a tetraploidal (4N) DNA state compared to the same cells in monolayer. Flow cytometry analysis and 3H-thymidine incorporation studies identified the delay of cell division as a consequence of a block in the G2/M of the cell cycle and not an inhibition of DNA synthesis. The inclusion of 150 microg/ml of hyaluronic acid (HA) in the manufacture of fibroblast populated collagen lattices (FPCL) caused a stimulation of cell division, as determined by cell counting; increased the expression of tubulin, as determined by Western blot analysis; and reduced the proportion of cells in a 4N state, as determined by flow cytometry. HA added to the same cells growing in monolayer produced a minimal increase in the rate of cell division or DNA synthesis. HA supplementation of FPCLs stimulated cell division as well as tubulin concentrations, but it did not enhance lattice contraction. The introduction of tubulin isolated from pig brain or purchased tubulin into fibroblasts by electroporation prior to their transfer into collagen lattices promoted cell division in the first 24 hours and enhanced FPCL contraction. It is proposed that tubulin protein, the building blocks of microtubules, is limited in human fibroblasts residing within a collagen matrix. When human fibroblasts are suspended in collagen, one effect of added HA may be to stimulate the synthesis of tubulin which assists cells through the cell cycle.