Two types of cDNAs for human macrophage scavenger receptors were cloned from a cDNA library derived from the phorbol ester-treated human monocytic cell line THP-1. The type I and type II human scavenger receptors encoded by these cDNAs are homologous (73% and 71% amino acid identity) to their previously characterized bovine counterparts and consist of six domains: cytoplasmic (I), membrane-spanning (II), spacer (Ill), ae-helical coiled-coil (IV), collagen-like (V), and a type-specific C-terminal (VI). The receptor gene is located on human chromosome 8. The human receptors expressed in CHO-K1 cells mediated endocytosis of modified low density lipoproteins. Two mRNAs, 4.0 and 3.2 kiobases, have been detected in human liver, placenta, and brain. Immunohistochemical studies using an anti-peptide antibody which recognizes human scavenger receptors indicated the presence of the scavenger receptors in the macrophages of lipid-rich atherosclerotic lesions, suggesting the involvement of scavenger receptors in atherogenesis.The macrophage scavenger receptors are trimeric membrane glycoproteins implicated in the pathologic deposition of cholesterol in arterial walls during atherogenesis (1,2). The molecular cloning of bovine scavenger receptor cDNAs has revealed several unexpected features (3, 4). Two types of receptor subunits exist, and both of these receptor proteins contain two extracellular domains that are predicted to form a long triple-stranded a-helical coiled coil and a collagen-like triple helix (3, 4). These receptors mediate the endocytosis of a diverse group of macromolecules, including modified low density lipoproteins (LDLs) (1-5). When cultured macrophages are exposed to appropriately modified LDLs, they are converted to cholesteryl ester-rich foam cells which are strikingly similar to the foam cells found in atherosclerotic plaques (1). Recent in vivo studies support the suggestion that modified LDLs, possibly internalized via the scavenger receptors, may play a critical role in the development of atherosclerosis (6)(7)(8).To study the role of human scavenger receptors in atherogenesis, we have cloned human scavenger receptor cDNAs.tt From the deduced amino acid sequence, we generated rabbit anti-peptide antiserum that recognizes human macrophage receptors. Immunohistochemical studies using this antibody have revealed the presence of immunoreactive scavenger receptor protein in the macrophages ofatherosclerotic lesions, suggesting the involvement of scavenger receptors in atherogenesis. MATERIALS AND METHODSMolecular Cloning of Human Scavenger Receptor cDNAs. THP-1 cells were cultivated in the presence of 200 nM phorbol 12-myristate 13-acetate (PMA) for 4 days (2). Poly(A)+ RNA was isolated from these cells and was used to construct a size-fractionated oligo(dT)-primed cDNA library in A ZAP 11 (3). The Xba I-Sph I fragment of pBSR7 corresponding to the collagen-like domain of the bovine receptor (3) labeled by random priming was used as a hybridization probe to screen 6 x 105 plaques. Two positive...

Although the mechanisms underlying the spatial pattern formation of sensory maps have been extensively investigated, those triggering sensory map formation during development are largely unknown. Here we show that the birth of pups instructively and selectively regulates the initiation of barrel formation in the somatosensory cortex by reducing serotonin concentration. We found that preterm birth accelerated barrel formation, whereas it did not affect either barreloid formation or barrel structural plasticity. We also found that serotonin was selectively reduced soon after birth and that the reduction of serotonin was triggered by birth. The reduction of serotonin was necessary and sufficient for the effect of birth on barrel formation. Interestingly, the regulatory mechanisms described here were also found to regulate eye-specific segregation in the visual system, suggesting that they are utilized in various brain regions. Our results shed light on roles of birth and serotonin in sensory map formation.

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TO ESTABLISH a sterilization method with minimal heating, the effect of high pressure on bacteriostasis was studied using thermoduric spores of Bacillus stearofhennophilus. After exposure to 800 MPa for 60 min at 6O"C, the spore count decreased from lo6 to 102/mL. However, exposure to the same pressure at room temperature did not cause significant change in spore numbers. The synergistic effect of high pressurization on the bacteriostatic action of sucrose fatty acid ester at low concentration (< 10 ppm) was pronounced with sucrose palmitic acid ester but not with sucrose stearic acid ester. Oscillatory pressurization was more effective for spore sterilization. Six cycles oscillation of S-min pressurization with 400 MPa at 70°C decreased the spore count from 10" to 102/mL, and with 600 MPa, complete sterilization was achieved.

In order to investigate the relationship between oral sensorimotor ability and masticatory function, an oral stereognosis ability (OSA) test, masticatory performance and efficiency was employed for 15 dentate subjects. Subjects were instructed to orally identify OSA test pieces blindly. The response score and sum of the duration time for identification were used for analysis as OSA score and OSA response time. Masticatory function was evaluated using a sieving method with 3 g of peanuts. Masticatory performance was calculated with the weight percentage of portions finer than 1700 microm by the total volume after 20 chewing strokes. Masticatory efficiency was calculated by the declination rate of median particle size which is defined by the Rosin-Rammler equation. To analyse the relationship between OSA variables and masticatory ability, the correlation coefficient was calculated. The results summarized as a significant correlation was found only between OSA score and masticatory efficiency. However, a significant correlation could not be found between other OAS variables and masticatory ability. It was revealed that positive correlation existed between oral stereognosis ability and masticatory ability. It was suggested that the role of oral sensorimotor function might affect the masticatory function.

In this study, the effects of filler type and polishing on the discoloration of composite resin artificial teeth were examined. Four types of experimental resins were prepared: one was a matrix resin, while the others were composite resins containing three different types of fillers (nano-sized silica filler with or without silanization, and prepolymerized filler). Specimens were immersed in distilled water, coffee, red wine, or curry. Color change after immersion was measured using a colorimeter. Color difference values (ΔE) and changes in translucency parameter (ΔTP) were statistically analyzed using three-way ANOVA and Tukey's comparison. On the influence of the polishing factor, statistically significant differences were neither observed in ΔE nor ΔTP between polished and non-polished tooth surfaces. On the contrary, the influences of filler type and discoloration medium, and their interaction thereof, were significant. With unsilanized filler, the ΔE value of composite resin artificial teeth was significantly increased.

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MATERIALS & METHODSBoth native and denatured protein samples were examined by determining fluorescence and specific rotation, and by polyacrylamide gel electrophoresis (PAGE) and differential scanning calorimetry (DSC). Denaturation of ovalbumin by pressure was much less than by heat or by the chemical denaturants. Gvalbumin was denatured under high pressure, as confirmed by the decrease in its a-helical content to 72% and DSC endothermic enthalpy to 61%, but it showed no change in the PAGE pattern. With bovine serum albumin decrease in fluorescence was observed after denaturation by chemicals, but it did not change under high pressure.