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Notes: The nematic liquid-crystal director-orientation in the vicinity of the interface between a liquid-crystal layer and a glass substrate is evaluated in various orientations under an applied electric field, using shear horizontal (SH) wave propagation. The measured acoustic phase delay is related to numerical analysis of the propagation characteristics of the SH wave in a trilayer structure containing a nematic liquid-crystal layer (4-cyano-4′-pentylbiphenyl: 5CB) between two glass plates. This technique using SH wave propagation in a liquid-crystal cell is promising for evaluating the nematic liquid-crystal director angle in the vicinity of the interface. © 2002 American Institute of Physics.

Notes: We have previously reported that voltage-dependent Ca2+ (VDC) channels of rat melanotrophs are inhibited by prostaglandin E2 (PGE2). In this study, mechanisms involved in the inhibitory actions of PGE2 receptors of rat melanotrophs were analysed using reverse transcriptase-polymerase chain reaction (RT-PCR), Ca2+-imaging and whole-cell, patch-clamp techniques with recently developed EP agonists, each of which is selective for the known four subclasses of EP receptors (EP1–4). PGE2 reversibly suppressed the cytosolic Ca2+ concentration ([Ca2+]i). The maximum reduction in [Ca2+]i by PGE2 was comparable to that by dopamine or to that by extracellular Ca2+ removal. RT-PCR analysis of all four EP receptors revealed that EP3 and EP4 receptor mRNAs were expressed in the intermediate lobe. The effects of PGE2 to suppress [Ca2+]i were mimicked by the selective EP3 agonist, ONO-AE-248, whereas three other EP agonists, ONO-DI-004 (EP1), ONO-AE1-259 (EP2) and ONO-AE1-329 (EP4), had little or no effect on [Ca2+]i. All four G-protein activated inward rectifying K+ (GIRK) channel mRNAs were identified in intermediate lobe tissues by RT-PCR. Dopamine concentration-dependently activated GIRK currents, whereas PGE2 did not activate GIRK currents, even at the concentration causing maximal inhibition of VDC channels. These results suggest that PGE2 acts on EP3 receptors to suppress Ca2+ entry of rat melanotrophs by selectively inhibiting VDC channels of these cells. We have compared the possible cellular and molecular mechanisms of inhibition by dopamine and PGE2.

Notes: 1. The effects of channelisation on macroinvertebrates were examined in relation to a spate and flow refugia. Habitat components that can function as flow refugia were identified in a small, low-gradient stream in northern Hokkaido, Japan.2. Macroinvertebrates and their habitat characteristics (depth, current velocity and substratum) were sampled and measured in natural and channelised sections on three occasions: before, during and immediately after a spate. For macroinvertebrate sampling and habitat measurements, five (riffle, glide, pool, backwater and inundated habitats) and three (channelised-mid, channelised-edge and inundated habitats) habitat types were classified in the natural and channelised section, respectively.3. The rate of velocity increase with discharge was compared among habitat types to determine which habitat types were less affected by increased discharge. The rate was the highest in riffles followed by glides and channelised-mids. Backwaters maintained low current velocity even at high flow. In addition, current velocity in both natural and channelised inundated habitats was low relative to other habitat types during the spate.4. Through the spate, total density of macroinvertebrates in channelised-mids and taxon richness in both channelised-mids and edges decreased. In the natural section, however, such a significant decrease was not found except for taxon richness in pools. This indicated that the spate had a greater impact on assemblages in the channelised section. Riffle assemblages exhibited a rapid recovery immediately after the spate, suggesting the existence of flow refugia in the natural section. Among the habitat types we examined, backwaters and inundated habitats appeared to have acted as flow refugia, because these habitats accumulated macroinvertebrates during the spate.5. The lower persistence of the macroinvertebrate assemblage in the channelised section was attributable to the lower availability of flow refugia such as backwaters and inundated habitats. Our results emphasised the importance of considering flow fluctuations and refugia in assessing the effects of channelisation. In addition, the lateral heterogeneity of stream channels should be considered in stream restoration and management.

Notes: Background : Omeprazole 10 mg is used as maintenance therapy for gastro-oesophageal reflux disease, but previous reports have not mentioned the potency of its acid suppression.Aim : To evaluate the potency of acid suppression with omeprazole 10 mg, in relation to CYP2C19 genotypes.Methods : Eighteen healthy subjects without Helicobacter pylori participated. After a 7-day regimen of omeprazole 10 mg, 20 mg, lafutidine 20 mg (a novel H2-receptor antagonist) or water only (baseline data), intragastric pH was measured for 24 h.Results : With omeprazole 10 mg, greater differences were observed than 20 mg in median pH values and pH 〉 4 holding time ratios between poor metabolizers (PMs, n = 6) and the others [homozygous extensive metabolizers (homo-EMs, n = 6) and heterozygous extensive metabolizers (hetero-EMs, n = 6)]. With lafutidine 20 mg, these parameters were not influenced by the genotype. The potency of acid suppression was: omeprazole 20 mg ≈ lafutidine 20 mg 〉 omeprazole 10 mg in homo-EMs, omeprazole 20 mg 〉 omeprazole 10 mg ≈ lafutidine 20 mg in hetero-EMs, and omeprazole 20 mg ≈ omeprazole 10 mg 〉 lafutidine 20 mg in PMs.Conclusions : Omeprazole 10 mg strongly suppresses acid secretion, but depending on the CYP2C19 genotypes shows greater interindividual variations in suppression than 20 mg.

Notes: Summary We report a case of febrile ulceronecrotic Mucha–Habermann disease (FUMHD) in a 21-year-old man. This disease is a severe form of pityriasis lichenoides et varioliformis acuta (PLEVA) and is characterized by the sudden onset of diffuse ulcerations associated with high fever and systemic symptoms. It is sometimes lethal especially in elderly patients. In the present case, intense generalized maculopapular erythematous plaques with central necrosis developed progressively in association with a high fever. Initial treatment with systemic betamethasone had been unsuccessful and the skin lesions, which covered about 50% of the body surface, became severely ulcerated. Although the development of new lesions had ceased spontaneously, widespread ulceration of the skin remained. Debridement of the necrotic skin and skin grafting using cultured epidermal autografts and meshed allografts of cadaver skin led to prompt reepithelization.