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Atherosclerosis is a vascular disorder involving inflammation, a narrowed vascular lumen in the entire tunica intima, and reduced elasticity of the arterial wall. It has been found that Hsp60 from Chlamydia pneumoniae, an obligate bacterial pathogen associated with atheroma lesions, mimics human Hsp60, thereby causing attacks by immune cells on stressed endothelial cells expressing endogenous Hsp60 on their surface. Furthermore, Hsp60 from C. pneumoniae has been shown to promote the growth of vascular smooth muscle cells (VSMCs). To explore probes that can be used for studying signal transduction elicited by the chlamydial Hsp60, we have tested several natural products for their inhibitory actions on the Hsp60-induced proliferation of rat arterial smooth muscle cells. Sesamol, vanillyl alcohol, and trans-ferulic acid exhibited moderate inhibitory actions on the Hsp60-induced cell proliferation; zerumbone, humulene, and caryophylene effectively inhibited it at low concentrations with IC(50) values of 529, 122, and 110 nM, respectively. The results indicated that the 11-membered alicyclic ring is favorable for interactions with receptors involved in the Hsp60-induced VSMC proliferation.

Camurati-Engelmann disease (CED, MIM 131300) is an autosomal dominant, progressive diaphyseal dysplasia characterized by hyperosteosis and sclerosis of the diaphyses of long bones. We recently assigned the CED locus to an interval between D19S422 and D19S606 at chromosome 19q13.1-q13.3, which two other groups confirmed. As the human transforming growth factor-1 gene (TGFB1) is located within this interval, we considered it a candidate gene for CED.

The fatigue crack growth rate in HT80 base plate and welded joints has been measured using compact tension specimens, and examined by means of fracture mechanics and electron fractography.The lowest fatigue crack growth rate was obtained in the heat-affected zone and the highest rate in the stress-relieved weld metal. In the weld metal, the compressive residual stress affected the crack growth rate and reduced the effective stress intensity factor range ΔKeff.The fatigue crack growth rate coincided almost completely with the microscopic growth rate calculated from the striation spacing for base metal and heat-affected zone. The fatigue crack growth rate for both weld metal and stress-relieved weld metal was, however, higher than the microscopic growth rate in the present stress intensity factor range. It is supposed that this discrepancy is caused by the fracture accompanied with dimples and striations. The relation between the dimple size, ds(mm), and the stress intensity factor range, ΔK(kg/mm3/2), has been obtained as follows, ds=1.4×10-5·(ΔK)

Aptitude de ces polymeres a fixer le methyle orange a 5, 15, 25 et 35°C en solution aqueuse

Polyethylenimine (PEI) was crosslinked with dichloroethane, glyoxal, or glutaraldehyde and polymers of various degrees of crosslinkage were made. The insoluble polymers obtained were examined for their ability to bind methyl orange and its homologs, methyl, ethyl, propyl, and butyl orange at 5, 15, 25, and 35°C, respectively, in an aqueous solution. PEI crosslinked with glutaraldehyde showed markedly increased binding affinity toward these cosolutes compared with the polymers crosslinked with dichloroethane or glyoxal. The extent of the binding increased with an increase in the degree of crosslinkage. These results suggest that the enhancement of the binding by the crosslinking is due mainly to a dual effect, introduction of hydrophobic moieties and proximity of neighboring polymer chains. The first binding constants and the thermodynamic parameters that accompanied the binding were calculated. The thermodynamic data show that the binding process is athermal and is stabilized entirely by the entropy term. Water-soluble PEI exhibited stronger cooperative interactions than the crosslinked polymer because the mobilities of the chains of the former are greater than those of the latter.

Further study is made using three types of circuit shown in Fig. 1, because the arc plays an important role in flashing action.Oscillograms of flashing current in late stage of flashing process using three circuits are shown in Fig. 3. In the case of circuit I, the arcing current is held to continue for comparatively long duration by large leakage inductance of welding transformer (L0) In the case of circuit III, however, the arcing current decreases rapidly, because the arc energy is only supplied from the stored energy in the small inductance L. This means small heating per one arc.The short circuit current increases rapidly for circuit III for the same reason mentioned above. The rapid increase of short circuit current is effective to break the newly formed short circuit path due to the local concentration of joule's heat. The above mentioned characteristics concerning circuit III result' in frequent splashing of many droplets of small sizes under the same platen velocity as that in circuit I.Circuit characters affect the formation of molten metal layer in flashing period. In the case of circuit I, the molten metal layer is observed to locate on a part of test piece end. It is supposed that the molten metal on the central part is splashed off by powerful arc force. But, in the circuit II or III, molten metal layer of 0.5-0.2mm thickness is observed all over the end of test pieces.Thus, if the molten metal layer is formed all over the end of test pieces by selecting the circuit constant, welds with good mechanical properties are obtained, even though upset current is not allowed to flow by cutting off artificially the power circuit as soon as upsetting begins.