Localization of mRNA for inflammatory cytokines in radicular cyst tissue by in situ hybridization, and induction of inflammatory cytokines by human gingival fibroblasts in response to radicular cyst contents

The expression of mRNA encoding the inflammatory cytokines interleukin-1alpha (IL-1alpha), interleukin-1beta (IL-1beta), interleukin-6 (IL-6), interleukin-8 (IL-8) and tumor necrosis factor alpha(TNF-alpha) have been examined in radicular cysts by in situ hybridization. Furthermore, the biological activity of the contents of radicular cysts (RCC) has been assayed by adding extracts of RCC to cultured human gingival fibroblasts (HGFs) and analyzing the culture medium for the release of inflammatory cytokines. In the epithelial layer, keratinocytes expressed all cytokine mRNAs examined at various levels. Basal layer cells expressed mRNA for each cytokine. In the subepithelial granulation tissue of the cysts, fibroblasts and macrophages expressed mRNA for IL-6, IL-8, IL-1beta and TNF-alpha mRNA at varying levels; especially clear expression of TNF-alpha and IL-1beta mRNA was detected on macrophages. The infiltrating lymphoid cells, largely composed of T cells and plasma cells, expressed these cytokine mRNAs, especially those encoding IL-6 and IL-8, at various levels. In vitro analysis indicated dose-dependent release of both IL-6 and IL-8 by HGFs in response to RCC. After heating to 100 degrees C for 10 min, RCC almost completely failed to stimulate IL-6 release from HGFs. Furthermore, anti-IL-1beta antibody (neutralization test) did not prevent the stimulation of IL-6 release by RCC. Significant amounts of IL-6 and IL-8 were detected in RCC in two cases, and a trace amount of IL-1beta was detected in one case. This study demonstrated the wide expression of mRNA encoding inflammatory cytokines in radicular cyst tissues, and RCC itself was capable of stimulating IL-6 and IL-8 production from HGFs.     

TANGENTIAL VELOCITY CHANGE WITH TIME OF POLYACRYLAMIDE SOLUTION IN A CONCENTRIC ANNULUS

Tangential velocity change with time of polyacrylamide solution, which had not only viscosity but also elasticity, in a concentric annulus after step motion of the inner cylinder was measured by using a LDV method. By adapting a conception of a second order lag control system which had a feedback connection, an equation for estimating the velocity change with time was presented. Each parameter in the equation was determined based on the experimental results, and the relationships between each parameter and viscosity or elasticity of the solutions was made clear. By using this equation, the tangential velocity change with time of a viscoelastic liquid in the annulus can be estimated when the viscosity and elasticity of the liquid and the rotational speed of the inner cylinder are given. Additionally, it was confirmed that the equation was applicable to the case of polyethyleneoxide solution, which had different ranges of the viscosity and elasticity from those of the test solutions described above.     

Implications of gastric topical bioactive peptides in ammonia-induced acute gastric mucosal lesions in rats

BACKGROUND: Ammonia, one of the pathogenic factors in Helicobacter pylori-induced mucosal injury, induces acute mucosal lesions in the rat glandular stomach. METHODS: The effect of ammonia administered intragastrically on gastric peptides was investigated in urethane-anesthetized rats. RESULTS: Gastric mucosal lesions were observed 5 min after 0.3% ammonia (4 ml/kg, intragastrically). Immunoreactive endothelin-1 (ET-1) and immunoreactive thyrotropin-releasing hormone (TRH) concentrations in the gastric wall decreased significantly 2 min and 5 min after ammonia, respectively. A significant increase in gastric juice immunoreactive ET-1 and TRH levels was reciprocally observed. The severity of gastric mucosal injury and changes in gastric immunoreactive ET-1 and TRH concentrations were shown to be concentration-dependent 30 min after ammonia. Atropine (5 mg/kg, intraperitoneally, -20 min) prevented ammonia-induced injury accompanied by a block of changes in gastric immunoreactive ET-1 and TRH concentrations. BQ-485 (ET(A) receptor antagonist; 2 mg/kg, subcutaneously) also abolished ammonia-induced lesions and gastric immunoreactive TRH changes. CONCLUSIONS: These findings suggested that gastric ET-1 and TRH play a role in ammonia-induced gastric mucosal injury mediated via a muscarine and an ET(A) receptor.     

Trace elements in ribs of elderly people and elemental variation in the presence of chronic diseases

Element concentrations in ribs obtained from elderly Japanese people (17 males and 28 females; mean age, 81.5 years) were determined by atomic absorption spectrometry (AAS), inductively coupled plasma atomic emission spectrometry (ICP-AES), and ICP mass spectrometry (ICP-MS). Nine elements--Na, Mg, P, K, Ca, Fe, Zn, Sr, and Pb--were determinable in most of the subjects by a combination of AAS and ICP-AES. The levels of these elements were generally comparable with those obtained in our previous study on ribs from younger Japanese. By the use of ICP-MS, Sn (median, 0.79 micrograms/g dry bone) and Ba (1.3 micrograms/g) were determinable in all of the subjects analysed (n = 35) and 18 other elements at lower concentration levels were also detected in some of the subjects. An exploratory statistical analysis was carried out to find element(s) of which level(s) in rib vary in the presence of degenerative chronic diseases, using information obtained from pathological autopsy reports and medical histories of the present subjects. It indicated that (i) Pb and Zn, (ii) Ba, and (iii) Sr levels in the ribs varied in the presence of cancer, cerebrovascular damage, and bone problems, respectively. The present results were discussed in relation to the results of the previous epidemiologic and experimental studies.     

Molecular dynamic simulation of heterogeneity and chemical states of fluorine in amorphous alkaline earth silicate systems

Chemical states of fluorine in fluorosilicate glasses in the system MF₂-MO-SiO₂ (M = Ca, Sr and Ba; SiO₂ content < 60 mol%) have been investigated by molecular dynamic (MD) simulations with a perfect ionic two-body potential. Comparison of the results with those derived by X-ray photoelectron spectra of the actual glasses demonstrates that MD simulations reproduce well the bonding states of fluorine in the systems as well as the formation of M-F clusters. The MD generated structure of imaginary glasses, or glasses not obtained by the conventional melt-quench technique, with 70 mol% SiO₂ indicates that an acidic environment induces a greater amount of F---Si bonds. Their M-F pair correlation functions plotted against normalized M-F distances suggest that relative ion positions in the clusters are very similar.     

Theory of powdered metal formation in electrochemistry—morphological instability in galvanostatic crystal growth under diffusion control

Following the presentation of the theory of powder formation in steady state electrocrystallization, some equations based on the linear instability theory in non-steady state deposition under diffusion control were derived; the galvanostatic case was then analysed using the theoretical equations obtained here.As a result, the dependences of powder growth and particle size on various physical parameters, such as current density, bulk concentration and temperature, were made quantitatively clear. Furthermore, a reliable basis was given to the induction time of powder formation which had formerly been liable to amibiguous discussion.     

Distribution of ytterbium (Yb) in cells of Streptomyces sp. YB-1 which can accumulate Yb, and reusability of cells and cell membrane as bioadsorbent for Yb

The cells of Streptomyces sp. YB-1 adsorbed 4-6 mg ytterbium (Yb) per g dry weight. The Yb contents of the cell wall fraction, cell-free extract, and cell membrane fraction were 11%, 2%, and 87%, respectively. The Yb content in the cell membrane fraction was 20-25 mg per g dry weight. The adsorbed Yb could be quantitatively desorbed by treating the cell membrane fraction with 1 mM EDTA and 1 M HCl at 37 degrees C for 4 h. Treatment with 1 M NaOH caused Yb desorption to some extent. Treatments with proteinase K, lysozyme, 0.5% Triton X-100, 0.4% sodium dodecyl sulfate, and 1 M NaCl did not cause Yb desorption. Elemental analysis of Yb-adsorbed materials after removal of proteins and then extraction of lipids from the membrane fraction revealed that the molar ratio of Yb and P in the materials was about 1:1. The cells and the membrane fraction could be used repeatedly as a bioadsorbent for Yb.     

Evaluation of TEM samples of an Mg-Al alloy prepared using FIB milling at the operating voltages of 10 kV and 40 kV

Transmission electron microscopy (TEM) samples of an Mg-Al alloy has been prepared using a Ga-focused ion beam (FIB) milling at two different operating voltages of 10 kV and 40 kV to investigate the influence of the FIB energy on the sample quality. The fine structures of the samples have been studied using a high resolution TEM, and the concentration of the implanted Ga was analysed using an energy dispersive X-ray (EDX) analysis. The result of the TEM observation revealed that point defects were introduced to the sample finally milled at 40 kV but not at 10 kV. However, crystal lattice images and electron diffraction patterns were clearly observed on both the samples. The typical influence of the FIB energy was indicated in the elemental analysis. The relative Ga concentration in the thin sample finally milled at 10 kV was 1.0-2.0 at% that is less than half of 4.0-6.0 at% of the Ga concentration in the sample finally milled at 40 kV. A comparison between the experimental results of the Ga concentration measurement with simulation was also discussed.     

Simple and comprehensive two-dimensional reversed-phase HPLC using monolithic silica columns

Simple and comprehensive two-dimensional (2D)-HPLC was studied in a reversed-phase mode using monolithic silica columns for second-dimension (2nd-D) separation. Every fraction from the first column, 15 cm long (4.6-mm i.d.), packed with fluoroalkylsilyl-bonded (FR) silica particles, was subjected to the separation in the 2nd-D using one or two octadecylsilylated (C(18)) monolithic silica columns (4.6-mm i.d., 3 cm). Monolithic silica columns in the 2nd-D were eluted at a flow rate of up to 10 mL/min with separation time of 30 s that meets the fractionation every 15-30 s at the first dimension (1st-D) operated at a flow rate of 0.4-0.8 mL/min. Three cases were studied. (1) In the simplest scheme of 2D-HPLC, effluent of the 1st-D was directly loaded into an injector loop of 2nd-D HPLC for 28 s, and 2 s was allowed for injection. (2) Two six-port valves each having a sample loop were used to hold the effluent of the 1st-D alternately for 30 s for one 2nd-D column to effect comprehensive 2D-HPLC without the loss of 1st-D effluent. (3) Two monolithic silica columns were used for 2nd-D by using a switching valve and two sets of 2nd-D chromatographs separating each fraction of the 1st-D effluent with the two 2nd-D columns alternately. In this case, two columns of the same stationary phase (C(18)) or different phases, C(18) and (pentabromobenzyloxy)propylsilyl-bonded (PBB), could be employed at the 2nd-D, although the latter needed two complementary runs. The systems produced peak capacity of approximately 1000 in approximately 60 min in cases 1 and 2 and in approximately 30 min in case 3. The three stationary phases, FR, C(18), and PBB, showed widely different selectivity from each other, making 2D separations possible. The simple and comprehensive 2D-HPLC utilizes the stability and high efficiency at high linear velocities of monolithic silica columns.