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We have investigated 4-μm-band SO 3 absorption lines for in situSO 3 detection using a mid-infrared laser source based on difference frequency generation in a quasi-phase-matched LiNbO 3 waveguide. In the wavelength range of 4.09400-4.10600 μm, there were strong SO 3 absorption lines. The maximum absorption coefficient at a concentration of 170 ppmv was estimated to be about 3.2×10 -5   cm -1 at a gas temperature of 190°C. In coexistence with H 2 O, the reduction of the SO 3 absorption peak height was observed, which was caused by sulfuric acid formation. We discuss a method of using an SO 3 equilibrium curve to derive the total SO 3 molecule concentration.

Background & Aims: The relationship between single nucleotide polymorphisms (SNPs) and clinical outcomes has been intensively studied. We intended to determine SNPs of CYP2C19 and 23S rRNA of Helicobacter pylori by using rapid urease test (RUT)-positive gastric mucosal samples., Methods: One hundred thirty-nine patients with H pylori -positive results based on RUT completed 1-week treatment with lansoprazole 30 mg twice a day, clarithromycin 200 mg 3 times daily, and amoxicillin 500 mg 3 times daily. SNPs from adenine to guanine at positions 2142 and 2143 of 23S rRNA of H pylori (A2142G and A2143G) and SNPs from guanine to adenine at positions 681 in exon 5 (* 2 ) and 636 in exon 4 (* 3 ) of CYP2C19 were determined by the serial invasive signal amplification reaction assay by using DNAs extracted from gastric tissue samples already used for RUT. Minimum inhibitory concentrations of clarithromycin for H pylori were determined by culture test. CYP2C19 genotypes were classified into the rapid metabolizer (* 1 /* 1 ), intermediate metabolizer (* 1 /* 2 or * 1 /* 3 ), and poor metabolizer (* 2 /* 2 , * 2 /* 3 , or * 3 /* 3 ) groups., Results: H pylori strains with A2142G or A2143G mutation had higher minimum inhibitory concentrations for clarithromycin. Cure rates in rapid, intermediate, and poor metabolizer groups were 57.8% (95% confidence interval, 42.1%-72.4%), 88.2% (78.1%-94.8%), and 92.3% (74.9%-99.1%), respectively ( P < .001). Cure rates in strains with and without A2142G or A2143G mutation were 48.3% (29.4%-67.5%) and 87.3% (79.5%-92.7%), respectively ( P < .001)., Conclusions: SNPs of CYP2C19 and 23S rRNA of H pylori using RUT-positive gastric mucosal samples could be predictable determinants for H pylori eradication by triple therapy.

Prostaglandin (PG)D2, which has long been implicated in allergic diseases, is currently considered to elicit its biological actions through the DP receptor (DP). Involvement of DP in the formation of allergic asthma was recently demonstrated with DP-deficient mice. However, proinflammatory functions of PGD2 cannot be explained by DP alone. We show here that a seven-transmembrane receptor, CRTH2, which is preferentially expressed in T helper type 2 (Th2) cells, eosinophils, and basophils in humans, serves as the novel receptor for PGD2. In response to PGD2, CRTH2 induces intracellular Ca2+mobilization and chemotaxis in Th2 cells in a Galphai-dependent manner. In addition, CRTH2, but not DP, mediates PGD2-dependent cell migration of blood eosinophils and basophils. Thus, PGD2 is likely involved in multiple aspects of allergic inflammation through its dual receptor systems, DP and CRTH2.

A significant difference in the amount of exhaled mercury per hour between normal and acatalasemic mice was observed in 7 of 11 experiments for different periods of time. The total amount of mercury exhaled from acatalasemic mice was significantly higher than those of normal mice. The results confirm that the reduction of mercuric ion to metallic mercury occurs by recycling of mercury in the tissues and reoxidized metallic mercury to mercuric ion by catalase. Mercuric ion was reduced to metallic mercury in the presence of superoxide anion in vitro. The reduction rate of mercuric ion to metallic mercury in the presence of both superoxide anion and cytochrome C or nitro blue tetrazolium was higher than that in the presence of superoxide anion alone, and the reduction of mercuric ion by NADPH or NADH was also observed. The reduction of mercuric ion to metallic mercury by liver homogenates of acatalasemic mice was higher than that of normal mice.

Levels of mercury in the brain and liver of acatalasemic mice immediately following exposure to metallic mercury vapor or injection of metallic mercury were higher than those found in normal mice. Acatalasemic mice had decreased levels of mercury in the blood and kidneys when the levels were compared with those of normal mice, which indicated that catalase plays a role in oxidizing and taking up mercury. Thus, the brain/blood or liver/blood ratio of mercury concentration in acatalasemic mice was significantly higher than that of normal mice. These results suggest that metallic mercury in the blood easily passed through the blood-brain or blood-liver barrier. The levels of mercury distribution to the kidneys of normal and acatalasemic mice, 1 hr after injection of mercuric chloride solution, were higher than that of normal and acatalasemic mice, respectively, 1 hr after injection of metallic mercury.

Among the ferric compounds studied, cytochrome C, methemoglobin, lactoperoxidase, ferritin and ferric ion, in addition to catalase, had the ability to oxidize metallic mercury in the presence of hydrogen peroxide. On the other hand, hematin, the active center of catalase, did not oxidize metallic mercury. The results are consistent with the increased oxidation and uptake of mercury in the liver by acatalasemia mice.