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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: The LIM homeobox family of transcription factors is involved in many processes during the development of the mammalian central nerves system. L3, also called Lhx8 (L3/Lhx8), is a recently identified member of the LIM homeobox gene family and is selectively expressed in the medial ganglionic eminence (MGE). Our previous study demonstrated that L3/Lhx8-null mice specifically lacked cholinergic neurons in the basal forebrain. In this study, we reduced L3/Lhx8 function in the murine neuroblastoma cell line, Neuro2a (N2a), using L3/Lhx8-targeted small interfering RNA (siRNA) produced by H1.2 promoter-driven vector. The levels of cholinergic markers per cell were diminished without a reduction in the number of marker-positive cells. Intriguingly, GABAergic marker expression and the number of GABAergic cells were dramatically increased in the differentiating L3/Lhx8-knockdown N2a. These results suggest the possibility that L3/Lhx8 is involved in the determination of transmitter phenotypes (GABAergic or cholinergic cell fate) in a population of neurons during basal forebrain development.

Notes: This letter describes the memory effect of an AlGaAs/GaAs heterojunction field-effect transistor that contains InAs nanodots in the barrier layer. The device experiences a shift of threshold gate voltage, as a function of the amount of the electrons trapped in the nanodots. These trapped electrons can be injected by applying a positive gate voltage and be erased by a visible light illumination at negative gate bias. Although the shift of the threshold gate voltage volatilizes with the time after the memory programing operation, a considerable part of the shift is retained even after 100 h at room temperature. © 2000 American Institute of Physics.

Notes: The electrorheology (ER) effect of ferroelectric liquid crystals is observed under shear-horizontal (SH) wave propagation. The ER effect is strongly dependent on the orientation direction of the liquid-crystal molecule. The apparent viscosity is evaluated through the numerical analysis result on the propagation characteristics of a SH wave in a trilayer structure including a ferroelectric liquid-crystal (Chisso, CS1014) layer between two glass plates. The ER effect is examined by the relation between the orientation of smectic layers and the propagation direction of the SH wave. © 2001 American Institute of Physics.

Notes: The complete tack of pungency in pepper (Capsicum annuum L.) is controlled by a single recessive gene (c). To develop a molecular marker linked to the C locus, two segregating F2 populations (TM2 and TF2) derived from crosses between occasionally pungent and non-pungent peppers in C. annuum were used. Using the RAPD (random amplified polymorphic DNA) technique in combination with a bulked segregation analysis, two RAPD markers, OPD20-800 and OPY09-800, were obtained. Of the two markers, the more closely linked marker. OPY09-800, was converted into a codominant CAPS (cleaved amplified polymorphic sequence) marker using data from the alignment of the two allelic sequences. This CAPS marker was linked to the C locus (3.6 cM in the TF2 population), and polymorphism was detected among accessions within C. annuum. This marker might be helpful for the selection of a c gene in backcross and progeny tests in a conventional breeding system.

Notes: To construct an amplified-fragment length polymorphism (AFLP)-based molecular linkage map of zoysiagrass, the selfed progenies of a clone consisting of 78 individuals were analysed using 471 AFLP markers derived from 126 PstI/MseI primer combinations. Of these markers, 364 were grouped into 26 linkage groups. The maps covered a total length of 932.5 cM, with an average spacing of 2.6 cM between markers. This information proves useful for gene targeting, quantitative trait loci mapping, and marker-assisted selection in zoysiagrass.

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 : The polymorphic enzyme cytochrome P450 2C19 affects omeprazole metabolism. This influence on metabolism might affect serum gastrin levels, and safety, during long-term treatment of reflux oesophagitis.Aim : To examine the relationship between cytochrome P450 2C19 genotype and the safety profile of long-term omeprazole treatment.Methods : A total of 119 Japanese patients with recurrent reflux oesophagitis underwent cytochrome P450 2C19 genotyping prior to receiving daily omeprazole 10 mg or 20 mg for 6–12 months, during which adverse event frequency, serum gastrin levels and endoscopic findings were monitored.Results : The incidences of adverse events, serious adverse events and adverse events leading to withdrawal did not differ between homozygous extensive metabolizer (n = 46), heterozygous extensive metabolizer (n = 53) or poor metabolizer (n = 20) groups. In all genotype groups, serum gastrin increased during the first 3 months of dosing but stabilized thereafter. No significant differences were seen either in the rate of reflux oesophagitis healing or symptom improvement among genotype groups.Conclusions : Long-term treatment with omeprazole was well-tolerated in Japanese patients, irrespective of their cytochrome P450 2C19 metabolic genotype, indicating that dose adjustment depending on metabolic genotype is not required during treatment with omeprazole.

Notes: Background : Insufficient acid suppression is one of the main causes of proton pump inhibitor-refractory gastro-oesophageal reflux disease.Aim : To achieve more potent and long-lasting acid suppression, different dosage regimens of rabeprazole were compared in relation to the CYP2C19 genotype status.Methods : In a cross-over study, 18 healthy Helicobacter pylori-negative males (six homozygous extensive metabolizers, six heterozygous extensive metabolizers and six poor metabolizers) were given rabeprazole 10 mg once daily, 20 mg once daily or 10 mg twice daily, or water only (baseline data), for 7 days each. On day 7 of each regimen, 24-h intragastric pH-metry was performed.Results : No significant differences were observed in median pH values and pH 〉 4 holding time ratios between rabeprazole 10 mg once daily and 20 mg once daily. However, with rabeprazole 10 mg twice daily, these parameters were significantly higher than those with 20 mg once daily. The potency of acid suppression by rabeprazole was influenced by the CYP2C19 genotype status. The differences were somewhat significant but not large. The incidence of nocturnal acid breakthrough was lowest with rabeprazole 10 mg twice daily.Conclusions : Rabeprazole 10 mg twice daily, not 20 mg once daily, should be administered to achieve more potent and long-lasting acid suppression.