Close linkage of MEN2A with RBP3 locus in Japanese kindreds

Summary The gene responsible for multiple endocrine neoplasia type 2A (MEN2A) has recently been assigned to the pericentromeric region of chromsome 10 in European Caucasian kindreds by linkage analysis using a DNA marker, interstitial retinol-binding protein 3 (RBP3). We have found tight linkage between the MEN2A and RBP3 loci in Japanese MEN2A kindreds. The maximum lod score is 5.19 at a recombination fraction of 0.00. This result suggests that mutation of a certain gene close to RBP3 is responsible for MEN2A irrespective of ethnic backgrounds.     

Differentiation by cholinergic stimulation of positive inotropic actions mediated via alpha- and beta-adrenoceptors in the rabbit heart.

In the isolated rabbit papillary muscle, experiments were carried out in order to elucidate whether or not cholinergic stimulation produces a differential antagonistic action on the positive inotropic effects mediated $\text{via}$ β- and α-adrenoceptor stimulation. Carbachol (0.1–30 μM) alone scarcely affected the basal tension developed. The postive inotropic effects of phenylephrine (30 μM) in the presence of phentolamine and of isoprenaline, which were mediated $\text{via}$ β-adrenoceptors, were markedly inhibited by carbachol. Carbachol (3 μM) shifted the dose-response curve for isoprenaline in a parallel manner, and that for phenylephrine with phentolamine to the right and downwards. Carbachol administered during induction of the positive inotropic effects $\text{via}$ α-adrenoceptors by phenylephrine (30 μM) with pindolol or by methoxamine failed to inhibit these effects and increased further the tension developed. The dose-response curve for phenylephrine determined in the presence of pindolol was not affected by carbachol. The present results indicate that the cholinergic antagonism of the adrenergic action on the contractility of the mammalian ventricular myocardium is exerted specifically to the β-adrenoceptor-mediated action, but not to the α-adrenoceptor-mediated one.     

Redescription of Lepadichthys coccinotaenia Regan 1921 and description of Lepadichthys trishula sp. nov. from southern Japan (Gobiesocidae: Diademichthyinae)

Ichthyological Research - Lepadichthys coccinotaenia Regan 1921 (Gobiesocidae: Diademichthyinae) is redescribed on the basis of 60 specimens, including the holotype, and a new species of...     

Plectranthias maekawa,a new species of perchlet from the Tokara Islands,Kagoshima, Japan,with a review of Japanese records of P. wheeleri (Serranidae: Anthiadinae)

Ichthyological Research - A new species of perchlet, Plectranthias maekawa, is described on the basis of three specimens (58.2–65.1 mm standard length: SL) from the Tokara Islands,...     

Synanceia quinque,a new species of stonefish (Synanceiidae) from Borneo and Flores

A new species of stonefish, Synanceia quinque (Synanceiidae) is described on the basis of two specimens (61.5–84.4 mm standard length) collected off Sabah (Borneo), Malaysia and Flores, Indonesia. The new species is characterized by 12 pectoral-fin rays, and is most similar to Synanceia alula Eschmeyer and Rama-Rao 1973 (11 pectoral-fin rays in the latter vs. 14 or more in other congeners). Other characters distinguishing S. quinque from S. alula include numbers of pelvic-fin rays [I, 5 in the former vs. I, 3 or 4 (usually I, 4) in the latter], gill rakers (0 + 4 or 5 vs. 0 or 1 + 7), and five preopercular spines/skin flaps (upper three spines relatively well developed, lower two rudimentary) (vs. four preopercle spines, fifth spine or skin flap absent). An updated key to species of Synanceia is provided.

     

Phenacoscorpius longicaudalis,a new species of scorpionfish (Teleostei: Scorpaenidae) from Western Australia,with first records of Phenacoscorpius adenensis from the southeastern Indian Ocean

Ichthyological Research - Phenacoscorpius longicaudalis sp. nov. is described from 19 specimens collected in depths of 228–990 m off Western Australia, eastern Indian Ocean. The new...     

Rediagnosis of the monotypic genus Lepadicyathus Prokofiev 2005 (Gobiesocidae: Diademichthyinae) and redescription of Lepadicyathus minor (Briggs 1955), new combination

Ichthyological Research - A revised diagnosis is provided for the poorly known clingfish genus Lepadicyathus Prokofiev 2005. The genus belongs to Diademichthyinae (sensu Conway et al.) and is...     

Silica deposition in relation to ageing of leaf tissues in Sasa veitchii (Carriere) Rehder (Poaceae: Bambusoideae)

BACKGROUND AND AIMS: Silica deposition is one of the important characteristics of plants in the family Poaceae. There have been many investigations into the distribution, deposition and physiological functions of silica in this family. Two hypotheses on silica deposition have been proposed based on these studies. First, that silica deposition occurs passively as a result of water uptake by plants, and second, that silica deposition is controlled positively by plants. To test these two apparently contradictory hypotheses, silica deposition in relation to the ageing of leaf tissues in Sasa veitchii was investigated. METHODS: Tissues were examined using a light microscope and a scanning electron microscope equipped with an energy dispersive X-ray microanalyser. KEY RESULTS: The deposition process differed depending on cell type. In mesophyll tissue, fusoid cells deposited large amounts of silica depending on leaf age after maturation, while chlorenchyma cells deposited little. In epidermal tissue, comprised of eight cell types, only silica cells deposited large amounts of silica during the leaf's developmental process and none after maturation. Bulliform cells, micro-hairs and prickle hairs deposited silica densely and continuously after leaf maturation. Cork cells, guard cells, long cells and subsidiary cells deposited silica at low levels. CONCLUSIONS: The significance of these observations is discussed in relation to the two hypotheses proposed for silica deposition in Poaceae. The results of the present study clearly indicate that both hypotheses are compatible with each other dependent on cell types.