Discovery of the first Asian plethodontid salamander.

Nearly 70% of the 535 species of salamanders in the world are members of a single family, the Plethodontidae, or lungless salamanders. The centre of diversity for this clade is North and Middle America, where the vast majority (99%) of species are found. We report the discovery of the first Asian plethodontid salamander, from montane woodlands in southwestern Korea.

Uranium-series disequilibria as a means to study recent migration of uranium in a sandstone-hosted uranium deposit, NW China.

Uranium concentration and alpha specific activities of uranium decay series nuclides (234)U, (238)U, (230)Th, (232)Th and (226)Ra were measured for 16 oxidized host sandstone samples, 36 oxic-anoxic (mineralized) sandstone samples and three unaltered primary sandstone samples collected from the Shihongtan deposit. The results show that most of the ores and host sandstones have close to secular equilibrium alpha activity ratios for (234)U/(238)U, (230)Th/(238)U, (230)Th/(234)U and (226)Ra/(230)Th, indicating that intensive groundwater-rock/ore interaction and uranium migration have not taken place in the deposit during the last 1.0 Ma.

Mental health outcomes of cocaine-exposed children at 6 years of age.

Objective: To assess 6-year-old cocaine- and noncocaine-exposed children's mental health outcomes controlling for potential confounders.

Methods: The sample consisted of 322 children [169 cocaine exposed (CE) and 153 noncocaine exposed (NCE)] enrolled in a longitudinal study since birth. At age 6, children were assessed for mental health symptoms using the Dominic Interactive (DI), a child self-report measure, and the Child Behavior Checklist (CBCL), a caregiver report of behavioral problems.

The building blocks of planets within the 'terrestrial' region of protoplanetary disks.

Our Solar System was formed from a cloud of gas and dust. Most of the dust mass is contained in amorphous silicates, yet crystalline silicates are abundant throughout the Solar System, reflecting the thermal and chemical alteration of solids during planet formation. (Even primitive bodies such as comets contain crystalline silicates.

Cross-species amplification of Bovidae microsatellites and low diversity of the endangered Korean goral.

The Korean goral (Nemorhaedus caudatus) is an endangered species of wild goat. The conservation and management of this species could benefit from a better understanding of its genetic diversity and structure. Cross-species amplification of 34 Bovidae microsatellite loci was tested on a panel of 6 Korean gorals and 10 domestic goats.

Transformation of human umbilical mesenchymal cells into neurons in vitro.

Neuronal transplantation has provided a promising approach for treating neurodegenerative diseases. Recently, efforts have been directed at in vitro induction of various stem cells to transform into neurons. We report the first successful quantities in an in vitro attempt at directing the transformation into neurons of human umbilical mesenchymal cells, which are capable of rapid proliferation in vitro and are easily available.

Four-year language outcomes of children exposed to cocaine in utero.

A large cohort of children exposed to cocaine in utero (n=189) were followed prospectively from birth to 4 years of age and compared to nonexposed children (n=185) on the Clinical Evaluation of Language Fundamentals-Preschool (CELF-P), a measure of receptive and expressive language abilities. Children exposed to cocaine in utero performed more poorly on the expressive and total language measures than nonexposed children after controlling for confounding variables, including prenatal exposure to alcohol, marijuana, and tobacco, as well as medical and sociodemographic variables. Children exposed to cocaine had more mild receptive language delays than nonexposed children and were less likely to have higher expressive abilities.

Cognitive outcomes of preschool children with prenatal cocaine exposure.

Context: Because of methodological limitations, the results of the few prospective studies assessing long-term cognitive effects of prenatal cocaine exposure are inconsistent.

Objective: To assess effects of prenatal cocaine exposure and quality of caregiving environment on 4-year cognitive outcomes.

Design: Longitudinal, prospective, masked comparison cohort study from birth (September 1994-June 1996) to 4 years.

Biosorption of uranium by lake-harvested biomass from a cyanobacterium bloom.

The aim of this work was to study some basic aspects of uranium biosorption by powdered biomass of lake-harvested cyanobacterium water-bloom, which consisted predominantly of Microcystis aeruginosa. The optimum pH for uranium biosorption was between 4.0 and 8.

Children prenatally exposed to cocaine: developmental outcomes and environmental risks at seven years of age.

Data are equivocal regarding the long-term consequences of prenatal exposure to cocaine on school-aged children. We compared 101 children exposed prenatally to cocaine with 130 unexposed children on measures of intelligence, visual motor, and motor abilities at age 7 years. Bivariate analyses revealed that cocaine-exposed children scored significantly lower than comparison children on the abbreviated Wechsler Intelligence Scale for Children-Third Edition Verbal and Full Scale IQ scores, the Visual Motor Integration and Motor Coordination standardized scores, and the Bruininks-Oseretsky Fine Motor Composite score.

Heat-shock pretreatment prevents suppression of long-term potentiation induced by scopolamine in rat hippocampal CA1 synapses.

We examined the effect of heat-shock pretreatment on long-term potentiation (LTP) in the CA1 hippocampal slices of the rat using the muscarinic blocker scopolamine as the LTP (memory) suppressor. Time course study using immunohistochemical techniques indicated peak expression of HSP70 16 h after heat-shock treatment. Focusing on that time point we found tetanic stimulation (at 100 Hz) induced LTP of 191.

Notes on a discrepancy in mitochondrial DNA and allozyme differentiation in a pond frog Rana nigromaculata.

Analyses of complete 1143-base pair sequence of the mitochondrial cytochrome b gene demonstrated a sister relationship between Japanese R. nigromaculata and Korean R. plancyichosenica, but not with Korean R.

The physiological and morphological characteristics of interneurons caudal to the trigeminal motor nucleus in rats.

In this study we have characterized the membrane properties and morphology of interneurons which lie between the caudal pole of the trigeminal motor nucleus and the rostral border of the facial motor nucleus. Previous studies suggest that many of these interneurons may participate in the genesis of rhythmical jaw movements. Saggital brainstem slices were taken from rats aged 5-8 days.

A new species of lentic breeding Korean salamander of the genus Hynobius (Amphibia, Urodela).

A new species of salamander, Hynobius yangi, is described from Kori (=Hyoam-ri), Busan-shi, southeastern Korea. It is a lentic breeder belonging to the H. nebulosus species group, and has long been confused with another Korean species H.

The effect of prior prolonged low frequency stimulation on the further synaptic plasticity at hippocampal CA1 synapses.

The objective of this study is to determine the role of prior prolonged low frequency stimulation (900 pulses at 1 Hz) on the further induced long-term potentiation (LTP) and depression (LTD) of synaptic activity in the rat hippocampal CA1 area. Hippocampal slices and standard extracellular field potential recording techniques were employed. LTP and LTD were induced using stimulation at 5 Hz (900 pulses) paired with or without simultaneous application of 1 microM isoproterenol respectively, at either normal CA1 synapses or CA1 synapses that were pre-conditioned with prolonged low frequency stimulation at 1 Hz.

Enhancement of associative long-term potentiation by activation of beta-adrenergic receptors at CA1 synapses in rat hippocampal slices.

The objective of this study was to evaluate the role of beta-adrenergic receptors in modulating associative long-term potentiation (LTP) induced at CA1 synapses. Two independent Schaffer collateral pathways were stimulated in hippocampal slices. The field EPSP (fEPSP) response evoked in one pathway (the weak pathway) was small, whereas a large response, usually 80-90% of the maximum, was evoked in the strong pathway.

Maltosyl-erythritol, a major transglycosylation product of erythritol by Bacillus stearothermophilus maltogenic amylase.

This study was done to modify erythritol to change its physicochemical and sensory properties. Erythritol, a four-carbon sugar alcohol, was transglycosylated by Bacillus stearothermophilus maltogenic amylase with maltotriose as a donor molecule. The presence of various transglycosylation products of erythritol was confirmed by TLC and high performance ion exchange chromatography (HPIC).

Change in bi-directional plasticity at CA1 synapses in hippocampal slices taken from 6-hydroxydopamine-treated rats: the role of endogenous norepinephrine.

The object of the present study is to investigate the role of endogenous adrenergic innervation in regulating bi-directional synaptic plasticity in rat hippocampal CA1 synapses. The endogenous adrenergic system was eliminated by giving subcutaneous injection of 6-hydroxydopamine (6-OHDA) to rats immediately after birth, and the animals were killed for experiments at postnatal ages of 25-35 days. In hippocampal slices taken from 6-OHDA-treated animals, theta-burst stimulation at 100 Hz failed to induce long-term potentiation (LTP) at CA1 synapses.

ADP-ribosylation factor 1 of Arabidopsis plays a critical role in intracellular trafficking and maintenance of endoplasmic reticulum morphology in Arabidopsis.

ADP-ribosylation factors (Arf), a family of small GTP-binding proteins, play important roles in intracellular trafficking in animal and yeast cells. Here, we investigated the roles of two Arf homologs, Arf1 and Arf3 of Arabidopsis, in intracellular trafficking in plant cells. We generated dominant negative mutant forms of Arf 1 and Arf3 and examined their effect on trafficking of reporter proteins in protoplasts.

Role of GABA(B) receptor in the regulation of excitatory synaptic transmission in trigeminal motoneurons.

The aim of the present study was to determine if excitatory synaptic transmission onto trigeminal motoneurons is subject to a presynaptic modulation by gamma-aminobutyric acid (GABA) via GABA(B) receptor in this system. Whole cell recordings were made from trigeminal motoneurons in longitudinal brain stem slices taken from 8-day-old rats. Monosynaptic excitatory postsynaptic potential (EPSP) activity was evoked by placing bipolar stainless steel electrodes dorsal-caudal to the trigeminal motor nucleus.

Genetic relationships among Korean brown frog species (Anura, Ranidae), with special reference to evolutionary divergences between two allied species Rana dybowskii and R. huanrenensis.

Allozyme analysis for 41 populations of brown frog species, Rana dybowskii, R. huanrenensis, and R. amurensis from Korea and three reference species (Chinese R.

The intermolecular interaction between the PH domain and the C-terminal domain of Arabidopsis dynamin-like 6 determines lipid binding specificity.

Dynamin and its related proteins are a group of mechanochemical proteins involved in the modulation of lipid membranes in various biological processes. Here we investigate the nature of membrane binding of the Arabidopsis dynamin-like 6 (ADL6) involved in vesicle trafficking from the trans-Golgi network to the central vacuole. Fractionation experiments by continuous sucrose gradients and gel filtration revealed that the majority of ADL6 is associated with membranes in vivo.

Template requirements for de novo RNA synthesis by hepatitis C virus nonstructural protein 5B polymerase on the viral X RNA.

The hepatitis C virus (HCV)-encoded NS5B protein is an RNA-dependent RNA polymerase which plays a substantial role in viral replication. We expressed and purified the recombinant NS5B of an HCV genotype 3a from Esherichia coli, and we investigated its ability to bind to the viral RNA and its enzymatic activity. The results presented here demonstrate that NS5B interacts strongly with the coding region of positive-strand RNA, although not in a sequence-specific manner.

Recombinant polioviruses expressing hepatitis B virus-specific cytotoxic T-lymphocyte epitopes.

T-cell immune response to recombinant poliovirus expressing foreign antigens has not been elucidated well. In order to investigate the potential use of poliovirus as a T-cell vaccine vector, we constructed recombinant polioviruses expressing HBV-derived CTL epitopes, HBsAg(28-39) (L(d)-restricted; IPQSLDSWWTSL) and HBc(93-100) (K(b)-restricted; MGLKFRQL) at the junction between the P2 and P3 regions, designated V3CDs and V3CDc, respectively. The V3CDs and V3CDc recombinant viruses replicated efficiently in HeLa cells and showed a similar infection profile to that of the wild-type Mahoney strain in one-step growth kinetics.