Climate oscillation during the Quaternary associated with landscape heterogeneity promoted allopatric lineage divergence of a temperate tree Kalopanax septemlobus (Araliaceae) in East Asia

We investigated the biogeographic history of Kalopanax septemlobus, one of the most widespread temperate tree species in East Asia, using a combined phylogeographic and palaeodistribution modelling approach. Range-wide genetic differentiation at nuclear microsatellites (G'(ST) = 0.709; 2205 samples genotyped at five loci) and chloroplast DNA (G(ST) = 0.697; 576 samples sequenced for 2055 bp at three fragments) was high. A major phylogeographic break in Central China corresponded with those of other temperate species and the spatial delineation of the two temperate forest subkingdoms of East Asia, consistent with the forests having been isolated within both East and West China for multiple glacial-interglacial cycles. Evidence for multiple glacial refugia was found in most of its current range in China, South Japan and the southernmost part of the Korean Peninsula. In contrast, lineage admixture and absence of private alleles and haplotypes in Hokkaido and the northern Korean Peninsula support a postglacial origin of northernmost populations. Although palaeodistribution modelling predicted suitable climate across a land-bridge extending from South Japan to East China during the Last Glacial Maximum, the genetic differentiation of regional populations indicated a limited role of the exposed sea floor as a dispersal corridor at that time. Overall, this study provides evidence that differential impacts of Quaternary climate oscillation associated with landscape heterogeneity have shaped the genetic structure of a wide-ranging temperate tree in East Asia.     

Protease Activity of Procaspase-8 Is Essential for Cell Survival by Inhibiting Both Apoptotic and Nonapoptotic Cell Death Dependent on Receptor-interacting Protein Kinase 1 (RIP1) and RIP3

Caspase-8 has an important role as an initiator caspase during death receptor-mediated apoptosis. Moreover, it has been reported to contribute to the regulation of cell fate in various types of cells including T-cells. In this report, we show that caspase-8 has an essential role in cell survival in mouse T-lymphoma-derived L5178Y cells. The knockdown of caspase-8 expression decreased the growth rate and increased cell death, both of which were induced by the absence of protease activity of procaspase-8. The cell death was associated with reactive oxygen species (ROS) accumulation, caspase activation, and autophagosome formation. The cell death was inhibited completely by treatment with ROS scavengers, but only partly by treatment with caspase inhibitors, expression of Bcl-xL, and knockdown of caspase-3 or Atg-7 which completely inhibits apoptosis or autophagosome formation, respectively, indicating that apoptosis and autophagy-associated cell death are induced simultaneously by the knockdown of caspase-8 expression. Further analysis indicated that RIP1 and RIP3 regulate this multiple cell death, because the cell death as well as ROS production was completely inhibited by not only treatment with the RIP1 inhibitor necrostatin-1, but also by knockdown of RIP3. Thus, in the absence of protease activity of procaspase-8, RIP1 and RIP3 simultaneously induce not only nonapoptotic cell death conceivably including autophagic cell death and necroptosis but also apoptosis through ROS production in mouse T-lymphoma cells.     

Metabolic design for cyanobacterial chemical synthesis

Photosynthetic chemical production in cyanobacteria is a promising technology for renewable energy, CO₂ mitigation, and fossil fuel replacement. Metabolic engineering has enabled a direct biosynthetic process from CO₂ fixation to chemical feedstocks and biofuels, without requiring costly production, storage, and breakdown of cellulose or sugars. However, direct production technology is challenged by a need to achieve high-carbon partitioning to products in order to be competitive. This review discusses principles for the design of biosynthetic pathways in cyanobacteria and describes recent advances in relevant genetic tools. This field is at a critical juncture in assessing the strength and feasibility of carbon partitioning. To address this, we have included the stoichiometry of reducing equivalents and carbon conservation for heterologous pathways, and a method for calculating product yields against a theoretical maximum.     

The effect of water loading on the urinary ratio of cortisone to cortisol in healthy subjects and a new approach to the evaluation of the ratio as an index for in vivo human 11β-hydroxysteroid dehydrogenase 2 activity

Factors that give rise to a large variation in the urinary ratio of free cortisone to cortisol (UFE/UFF) were investigated to accurately estimate 11β-hydroxysteroid dehydrogenase 2 (11β-HSD2) activity in humans in vivo. A water loading test was first carried out in two healthy subjects to examine the effect of water intake or urine volume on the urinary ratio of free cortisone to cortisol (UFE/UFF). The ratio was found to increase by water loading. We also examined urinary concentrations and amounts of cortisol, cortisone, creatinine, Na(+), K(+), and Cl(-), and urine volume, as possible factors affecting the urinary ratio (UFE/UFF), in 60 urine samples obtained from 15 healthy volunteers. Among these factors tested, the urinary concentration of cortisol was most highly correlated with the UFE/UFF ratio (r=-0.858), indicating that the in vivo activity of 11β-HSD2 (UFE/UFF) should fluctuate with the changes of the urinary concentration of cortisol. Based on the findings, we proposed a new estimation method of in vivo activity of 11β-HSD2 in humans, using the UFE/UFF ratio correlated with the urinary concentration of cortisol (UFE/UFF-cortisol concentration). Taking into consideration the intra-individual variabilities in the urinary concentration of cortisol, there were no significant within-day variations in 11β-HSD2 activity. The findings indicate that 11β-HSD2 activities can be accurately evaluated by simply measuring free cortisol and cortisone concentrations in spot urine samples. Furthermore, administrations of glycyrrhetinic acid in three healthy volunteers were performed to confirm the usefulness of the present assessment for the activity of 11β-HSD2.     

Agrobacterium-mediated transformation of the haploid liverwort Marchantia polymorpha L., an emerging model for plant biology

Agrobacterium-mediated transformation has not been practical in pteridophytes, bryophytes and algae to date, although it is commonly used in model plants including Arabidopsis and rice. Here we present a rapid Agrobacterium-mediated transformation system for the haploid liverwort Marchantia polymorpha L. using immature thalli developed from spores. Hundreds of hygromycin-resistant plants per sporangium were obtained by co-cultivation of immature thalli with Agrobacterium carrying the binary vector that contains a reporter, the beta-glucuronidase (GUS) gene with an intron, and a selection marker, the hygromycin phosphotransferase (hpt) gene. In this system, individual gemmae, which arise asexually from single initial cells, were analyzed as isogenic transformants. GUS activity staining showed that all hygromycin-resistant plants examined expressed the GUS transgene in planta. DNA analyses verified random integration of 1-5 copies of the intact T-DNA between the right and the left borders into the M. polymorpha genome. The efficient and rapid Agrobacterium-mediated transformation of M. polymorpha should provide molecular techniques to facilitate comparative genomics, taking advantage of this unique model plant that retains many features of the common ancestor of land plants.     

Does local heating-induced nitric oxide production attenuate vasoconstrictor responsiveness to lower body negative pressure in human skin?

We tested the hypothesis that local heating-induced nitric oxide (NO) production attenuates cutaneous vasoconstrictor responsiveness. Eleven subjects (6 men, 5 women) had four microdialysis membranes placed in forearm skin. Two membranes were perfused with 10 mM of N(G)-nitro-L-arginine (L-NAME) and two with Ringer solution (control), and all sites were locally heated to 34 degrees C. Subjects then underwent 5 min of 60-mmHg lower body negative pressure (LBNP). Two sites (a control and an L-NAME site) were then heated to 39 degrees C, while the other two sites were heated to 42 degrees C. At the L-NAME sites, skin blood flow was elevated using 0.75-2 mg/ml of adenosine in the perfusate solution (Adn + L-NAME) to a similar level relative to control sites. Subjects then underwent another 5 min of 60-mmHg LBNP. At 34 degrees C, cutaneous vascular conductance (CVC) decreased (Delta) similarly at both control and L-NAME sites during LBNP (Delta7.9 +/- 3.0 and Delta3.4 +/- 0.8% maximum, respectively; P > 0.05). The reduction in CVC to LBNP was also similar between control and Adn + L-NAME sites at 39 degrees C (control Delta11.4 +/- 2.5 vs. Adn + L-NAME Delta7.9 +/- 2.0% maximum; P > 0.05) and 42 degrees C (control Delta1.9 +/- 2.7 vs. Adn + L-NAME Delta 4.2 +/- 2.7% maximum; P > 0.05). However, the decrease in CVC at 42 degrees C, regardless of site, was smaller than at 39 degrees C (P < 0.05). These results do not support the hypothesis that local heating-induced NO production attenuates cutaneous vasoconstrictor responsiveness during high levels of LBNP. However, elevated local temperature, per se, attenuates cutaneous vasoconstrictor responsiveness to LBNP, presumably through non-nitric oxide mechanisms.     

Dichorionic triplets following frozen-thawed poor-stage embryo transfer: a report of two cases and a review

Background

We describe two cases of dichorionic triplet pregnancy after a frozen-thawed poor-stage embryo transfer.

Main body of the abstract

A 39-year-old and a 41-year-old woman underwent ART treatment. The first patient underwent intracytoplasmic sperm injection (ICSI) at 34 years of age, and two frozen-thawed poor-stage embryos were transferred at 39 years of age with assisted hatching, resulting in a trichorionic triamniotic triplet pregnancy. The second patient underwent ICSI, and two poor-grade blastocysts were transferred followed by assisted hatching, resulting in a dichorionic triamniotic triplet pregnancy.In the first case, the heartbeat of one monozygotic twin fetus had stopped on day 48 post-transfer (9 weeks 2 days), resulting in a dichorionic diamniotic twin pregnancy. A healthy boy and girl were delivered by elective caesarean section at 36 weeks, 5-days gestation. In the second case, the patient underwent selective reduction of the monochorionic twins, resulting in a single pregnancy that was vaginally delivered without any problems at 38 weeks 0-days gestation.

Short conclusions

Numerous factors may be associated with the development of a monochorionic pregnancy; however, controversies still remain. The present morphological grading for embryos is insufficient for inhibiting the development of a monochorionic pregnancy.

     

Up-regulated L-type high voltage-gated calcium channels cause increase in diazepam binding inhibitor induced by sustained morphine exposure in mouse cerebrocortical neurons

Mechanisms of increase in diazepam binding inhibitor (DBI) mRNA expression in mouse cerebrocortical neurons after sustained morphine exposure were investigated. Increases in DBI and its mRNA expressions induced by sustained morphine (0.3 μM) exposure for 3 days were completely abolished by naloxone and nifedipine, but not by ω-agatoxin VIA and ω-conotoxin GIVA. Increase in [³H]diltiazem binding to the particulate fractions from the morphine-treated neurons was due to increased B_max value with no changes in K_d value. Western blot analysis on l-type high voltage-gated calcium channel (HVCC) subunits revealed the increased expressions of α1C, α1D, and α2/δ1 subunits and decreased of β4 subunit expression, whereas expression of N- and P/Q-type HVCC subunits was not changed. These results indicate that morphine-induced increase in DBI mRNA expression is mediated via increased Ca²⁺ entry through up-regulated l-type HVCCs.     

Mn accumulation in a submerged plant Egeria densa (Hydrocharitaceae) is mediated by epiphytic bacteria

Many aquatic plants act as biosorbents, removing and recovering metals from the environment. To assess the biosorbent activity of Egeria densa, a submerged freshwater macrophyte, plants were collected monthly from a circular drainage area in Lake Biwa basin and the Mn concentrations of the plants were analysed. Mn concentrations in these plants were generally above those of terrestrial hyperaccumulators, and were markedly higher in spring and summer than in autumn. Mn concentrations were much lower in plants incubated in hydroponic medium at various pH levels with and without Mn supplementation than in field‐collected plants. The precipitation of Mn oxides on the leaves was determined by variable pressure scanning electron microscopy‐energy dispersive X‐ray analysis and Leucoberbelin blue staining. Several strains of epiphytic bacteria were isolated from the field‐collected E. densa plants, with many of these strains, including those of the genera Acidovorax, Comamonas, Pseudomonas and Rhizobium, found to have Mn‐oxidizing activity. High Mn concentrations in E. densa were mediated by the production of biogenic Mn oxide in biofilms on leaf surfaces. These findings provide new insights into plant epidermal bacterial flora that affect metal accumulation in plants and suggest that these aquatic plants may have use in Mn phytomining.     

A Contiguous Clone Map over 3 Mb on the Long Arm of Chromosome 11 across a Balanced Translocation Associated with Schizophrenia

Forty-nine clones derived by microdissection of a schizophrenia-associated t(1;11)(q42.1;q14.3) breakpoint region have been assigned by somatic cell hybrid mapping to seven discrete intervals on the long arm of human chromosome 11. Eleven of the clones were shown to map to a small region immediately distal to the translocation breakpoint on 11q.A 3-Mb contiguous clone map of this region was established by isolation of corresponding YAC recombinants. The contig was oriented and shown to traverse the translocation breakpoint by FISH and microsatellite marker analysis. This contig will facilitate the isolation of candidate sequences whose expression may be affected by the translocation.