A retrospective epidemiological analysis of non-accidental head injury in children in Scotland over a 15 year period

We have made a simple 15-year retrospective epidemiological study of a part of South Moravia, district Breclav, on the basis of genetic documentation of 245 congenital defects and 28 spontaneous abortions. The whole area was worked up by computer-geographical methods, and the occurrence of congenital defects was compared both in areas of severe chronic air pollution and in less contamined areas. There were three municipal areas, Mikulov, Breclav-Postorná, Velké Bilovice and their surroundings, in which an increased number of congenital defects was recorded. In the municipal area of Breclav-Postorná there was also a greater occurrence of organic solvents and phosphoric acid and a significantly higher occurrence of spontaneous abortions and at the same time a higher occurrence of heart defects.     

Genomic amplification of a decoy receptor for Fas ligand in lung and colon cancer

Fas ligand (FasL) is produced by activated T cells and natural killer cells and it induces apoptosis (programmed cell death) in target cells through the death receptor Fas/Apol/CD95. One important role of FasL and Fas is to mediate immune-cytotoxic killing of cells that are potentially harmful to the organism, such as virus-infected or tumour cells. Here we report the discovery of a soluble decoy receptor, termed decoy receptor 3 (DcR3), that binds to FasL and inhibits FasL-induced apoptosis. The DcR3 gene was amplified in about half of 35 primary lung and colon tumours studied, and DcR3 messenger RNA was expressed in malignant tissue. Thus, certain tumours may escape FasL-dependent immune-cytotoxic attack by expressing a decoy receptor that blocks FasL.     

The European Structural Integrity Society

The paper introduces the European Structural Integrity Society (ESIS) to the reader and describes its activities since its inception in the early 70s. President of the ESIS in 1992–1996. Published in Fizyko-Khimichna Mekhanika Materialiv. Vol. 32, No. 5, pp. 8–13, September–October, 1996.     

Different expression patterns of MMP-2 and MMP-9 in breast cancer

The role of nitric oxide (NO) in activation of cGMP is well established. It has been proposed that the ratio of cAMP to cGMP may be important in the regulation of preimplantation embryonic growth and differentiation. Therefore, we determined the ability of murine preimplantation embryos to produce NO. In addition, NO as an endogenous smooth muscle relaxant and vasodilator is a candidate for involvement in embryo implantation because this process requires increased vascular permeability and uterine quiescence at the sites of blastocyst apposition. Nitrite assays, an indirect measure of NO production, indicate that preimplantation murine embryos produce NO. This production was reversibly inhibited by culture of embryos in medium containing a nonspecific NO synthase (NOS) inhibitor (NG-nitro-L-arginine). Additionally, inhibition of normal development was observed in embryos cultured with NOS inhibitor. NO levels increased in culture medium when ovariectomized progesterone-treated animals were exposed to estrogen for 1 h in utero. Such hormonal treatment induces implantation. These data indicate that NO levels are regulated by estrogen and may be important in regulation of implantation. In addition, these data demonstrate for the first time that NO production appears to be required for normal embryonic development.     

Ca2+-dependent structural changes in C-type mannose-binding proteins

C-type animal lectins are a diverse family of proteins which mediate cell-surface carbohydrate-recognition events through a conserved carbohydrate-recognition domain (CRD). Most members of this family possess a carbohydrate-binding activity that depends strictly on the binding of Ca2+ at two sites, designated 1 and 2, in the CRD. The structural transitions associated with Ca2+ binding in C-type lectins have been investigated by determining high-resolution crystal structures of rat serum mannose-binding protein (MBP) bound to one Ho3+ in place of Ca2+, and the apo form of rat liver MBP. The removal of Ca2+ does not affect the core structure of the CRD, but dramatic conformational changes occur in the loops. The most significant structural change in the absence of Ca2+ is the isomerization of a cis-peptide bond preceding a conserved proline residue in Ca2+ site 2. This bond adopts the cis conformation in all Ca2+-bound structures, whereas both cis and trans conformations are observed in the absence of Ca2+. The pattern of structural changes in the three loops that interact with Ca2+ is dictated in large part by the conformation of the prolyl peptide bond. The highly conserved nature of Ca2+ site 2 suggests that the transitions observed in MBPs are general features of Ca2+ binding in C-type lectins.     

Rock mass characterization for underground hard rock mines

Rock mass characterization is an integral part of rock engineering practice. There are several classification systems used in underground mine design, however, most Canadian mines rely on only one of three classification systems. It is interesting to note that these systems—RQD, RMR and Q system—have their origins in civil engineering. This paper reviews the current state of these classification systems as employed in the mining industry. The first part focuses on the determination of the field parameters, with emphasis on the modifications to each parameter over the last 20 years. The difference between classification parameters that influence rock mass strength estimation and those that influence engineering design is emphasized. The second part of the paper focuses on the design recommendations based on these systems, such as maximum span, opening geometry, and support recommendations. The paper concludes with reference to errors that may arise in particular conditions.     

Pretreatment of astrocytes with interferon-alpha/beta impairs interferon-gamma induction of nitric oxide synthase

Excessive nitric oxide/peroxynitrite generation has been implicated in the pathogenesis of multiple sclerosis, and the demonstration of increased astrocytic nitric oxide synthase activity in the postmortem brain of multiple sclerosis patients supports this hypothesis. Exposure of astrocytes, in primary culture, to interferon-gamma results in stimulation of nitric oxide synthase activity and increased nitric oxide release. In contrast to interferon-gamma, interferon-alpha/beta had a minimal effect on astrocytic nitric oxide formation. Furthermore, pretreatment of astrocytes with interferon-alpha/beta inhibited (approximately 65%) stimulation by interferon-gamma of nitric oxide synthase activity and nitric oxide release. Treatment with interferon-alpha/beta at a concentration as low as 10 U/ml caused inhibition of mitochondrial cytochrome c oxidase. Furthermore, the damage to cytochrome c oxidase was prevented by the putative interferon-alpha/beta receptor antagonist oxyphenylbutazone. In view of these observations, our current hypothesis is that the mitochondrial damage caused by exposure to interferon-alpha/beta may impair the ability of astrocytes to induce nitric oxide synthase activity on subsequent interferon-gamma exposure. These results may have implications for our understanding of the mechanisms responsible for the therapeutic effects of interferon-alpha/beta preparations in multiple sclerosis.