Non‐monophyly of Bostrychia simpliciuscula (Ceramiales,Rhodophyta): Multiple species with very similar morphologies,a revised taxonomy of cryptic species

The discovery of a plethora of cryptic species in many algal groups has led to speculation as to the causes of this observation and has affected taxonomy, with reluctance to give names to species that look identical. While this is defensible for monophyletic cryptic species complexes, both our understanding of similar morphologies (crypsis) and nomenclature is challenged when we encounter non‐monophyletic ‘cryptic’ species. Bostrychia simpliciuscula is a wide‐ranging species in which multiple cryptic species are known. Our increased sampling shows that this species consists of four lineages that do not form a clade, but lineages are sister to species with different morphologies. Careful morphological examination shows that characters, especially branched monosiphonous laterals and rhizoid morphology in haptera, are able to distinguish these four lineages into two groups, that are still not monophyletic. The similar morphologies in these lineages could be due to convergence, but not developmental constraints or lack of time to diverge morphologically; or possibly maintenance of a generalized body plan. These lineages appear to have specific biogeographic patterns and these will be used to propose a new taxonomy. B. simpliciuscula is now confined to the tropics. Another of these lineages matches a previously described species, B. tenuissima, that was synonymized with B. simpliciuscula and is from cold temperate Australasia, and is resurrected. Another lineage is found in Japan in which a previous name is also available, B. hamana‐tokidae; the last lineage is found in central New South Wales, morphologically it resembles B. tenuissima, with which it overlaps in distribution around Sydney, and is named as a new species, B. kingii sp. nov.     

High species richness and genetic diversity of the genus Caloglossa (Delesseriaceae,Rhodophyta) in New Ireland,Papua New Guinea

Distribution patterns and genetic diversity of Caloglossa species have been studied in various regions but are still poorly understood around the tropical western Pacific where many marine organisms show high species richness. We explored the diversity of Caloglossa species in New Ireland, Papua New Guinea using morphological and genetic analyses. Seven species of Caloglossa (C. adhaerens, C. leprieurii, C. ogasawaraensis, C. bengalensis, C. postiae, C. saigonensis and C. vieillardii) were collected from eight sites; the latter four species are new records in Papua New Guinea. All specimens collected were cultured to compare their morphology under the same culture condition. Reproductive structures of gametophytes and/or sporophytes were described for the first time in some species from these collections. In C. leprieurii, gall‐like structure appeared in most gametophyte strains but not in tetrasporophytes. Such galls were produced from wing cells, and spermatangia and/or procarps were formed on many galls. The LSU rDNA and rbcL analyses revealed high intraspecific diversity in many species although the number of samples was limited and the sampling sites were within 200 km. We revealed high species richness and intraspecific genetic variation in Papua New Guinea, suggesting a hot spot for the diversity of Caloglossa.     

Gel–water relationships: Dielectric dispersion

At low frequencies, the dielectric constant of gels of agar, carboxymethyl cellulose, gelatin, mid maize starch is much higher than that of water. It decreases continuously as the frequency increases, tending to level off at about 10⁸ cps. The dielectric constant is lower the higher the concentration of polymer; it increases in the order: carboxymethyl cellulose, agar, starch, and gelatin. Results are most reasonably explained by assuming a more solid structure of water the lower the dielectric constant.     

Maturation-stimulation effect of brain extract and dibutyryl cyclic AMP on dissociated embryonic brain cells in culture

Extracts from adult rat brains contain a macromolecular factor capable of transforming dissociated embryonic rat brain cells in a monolayer culture. The factor simulates the activity of dibutyryl cyclic AMP but is not identical with either cyclic AMP or prostaglandin.     

Conformational changes of DNA by photoirradiation of DNA-bis(Zn(II)-cyclen)-azobenzene complex

Bis(Zn(II)-cyclen)-azobenzene derivative, which has two Zn(II)-macrocyclic tetraamine complexes connected through azobenzene spacer, has been synthesized as a cross-linking agent fordoublestranded DNA in aqueous solution. The Zn(II)-cyclen derivative selectively binds to A-T base pairs producing complexes between the Zn(II)-cyclen moiety and the imide-deprotonated thymine with breaking A-T base pairs. The azobenzene spacer undergoes cis/trans photoisomerization in the complex between the Zn(II)-cyclen derivative and the DNA duplex. The conformation of the DNA remarkably changed by photoisomerization of the azobenzene linker, when the Zn(II)-cyclen derivative binds to the DNA duplex with an interstrand cross-linking manner     

CIN85 is localized at synapses and forms a complex with S-SCAM via dendrin

Membrane-associated guanylate kinase inverted (MAGI)-1 plays a role as a scaffold at cell junctions in non-neuronal cells, while S-SCAM, its neuronal isoform, is involved in the organization of synapses. A search for MAGI-1-interacting proteins by yeast two-hybrid screening of a kidney cDNA library yielded dendrin. As dendrin was originally reported as a brain-specific postsynaptic protein, we tested the interaction between dendrin and S-SCAM and revealed that dendrin binds to the WW domains of S-SCAM. Dendrin is known to be dendritically translated but its function is largely unknown. To gain insights into the physiological meaning of the interaction, we performed a second yeast two-hybrid screening using dendrin as a bait. We identified CIN85, an endocytic scaffold protein, as a putative dendrin-interactor. Immunocytochemistry and subcellular fractionation analysis supported the synaptic localization of CIN85. The first SH3 domain and the C-terminal region of CIN85 bind to the proline-rich region and the N-terminal region of dendrin, respectively. In vitro experiments suggest that dendrin forms a ternary complex with CIN85 and S-SCAM and that this complex formation facilitates the recruitment of dendrin and S-SCAM to vesicle-like structures where CIN85 is accumulated.     

Delayed Increase of Brain Noradrenaline After Acute Footshock Stress in Rats

Several lines of evidence strongly suggest that accumulation of noradrenaline (NA) in the brain may underlie the hyperarousal symptoms experienced in post-traumatic stress disorder. In animal experiments, however, the effect of stress on NA content appears complex; acute stress reduces the level, while chronic stress tends to increase it. To explain this discrepancy, it is necessary to observe the long-term effects of acute stress on NA metabolism in the brain. In this study, rats were exposed to intermittent intense footshock stress for 1 h, and the brain NA content was measured for 7 days after the stress stimulus. Hypothalamic NA content was immediately reduced and recovered within 24 h. However, a significant NA increase was observed 7 days after the footshock. In the cerebral cortex and hippocampus, an increase in NA content was observed 1 day after the stress and lasted for at least 7 days. The fact that the content of 3-methoxy-4-hydroxyphenylglycol, a major NA metabolite, only transiently increased in all these regions possibly reflects NA release. These results indicate that increase in the brain NA content can be induced by acute stress, though its emergence is delayed. Importantly, this suggests that both acute and chronic stress may lead to NA accumulation under the same mechanism.     

Comparison of antioxidative effects between radon and thoron inhalation in mouse organs

Radon therapy has been traditionally performed globally for oxidative stress-related diseases. Many researchers have studied the beneficial effects of radon exposure in living organisms. However, the effects of thoron, a radioisotope of radon, have not been fully examined. In this study, we aimed to compare the biological effects of radon and thoron inhalation on mouse organs with a focus on oxidative stress. Male BALB/c mice were randomly divided into 15 groups: sham inhalation, radon inhalation at a dose of 500 Bq/m³ or 2000 Bq/m³, and thoron inhalation at a dose of 500 Bq/m³ or 2000 Bq/m³ were carried out. Immediately after inhalation, mouse tissues were excised for biochemical assays. The results showed a significant increase in superoxide dismutase and total glutathione, and a significant decrease in lipid peroxide following thoron inhalation under several conditions. Additionally, similar effects were observed for different doses and inhalation times between radon and thoron. Our results suggest that thoron inhalation also exerts antioxidative effects against oxidative stress in organs. However, the inhalation conditions should be carefully analyzed because of the differences in physical characteristics between radon and thoron.

     

Development of highly sensitive quantification method for testosterone and dihydrotestosterone in human serum and prostate tissue by liquid chromatography–electrospray ionization tandem mass spectrometry

We developed highly sensitive detection of testosterone (T) and 5α-dihydrotestosterone (DHT) by liquid chromatography–electrospray ionization tandem mass spectrometry using high proton affinitive derivatization of 17β-hydroxyl group of T and DHT with picolinic acid, mobile phase consisting of MeCN–MeOH–H₂O–formic acid and conventional octadecylsilica (ODS) column. Purification of the derivatives was carried out using solid-phase extraction with ODS cartridge. By this method, T and DHT were determined simultaneously with limits of quantification (LOQs) of 1 pg/0.2 ml in serum, and T and DHT with LOQs of 0.5 pg and 1 pg/3 mg in prostate tissue, respectively, under acceptable assay performance (intra-assay and inter-assay accuracy and precision). The present method provides reliable and reproducible results for quantification of T and DHT in small volumes of serum and prostate samples for diagnosis in prostatic disorders and male climacteric.     

Partial purification of a morphological transforming factor from pig brain.

A protein that changes one type of embryonic rat brain cell in culture from a primitive morphology to one resembling mature glial cell has been purified 400-fold from pig brain. The procedure includes differential centrifugation, ethanol treatment, trypsin digestion and column chromatography with Sephadex G-200 and Sepharose 4B. Although not completely homogeneous, the protein is biologically active at a concentration of 1-10(-8) M. It has a molecular weight of 350 000 and is heat labile. It is inactivated by the extremes of pH and by 8 M urea. The isoionic point is lower than neutrality. The activity is resistant to DNAase, RNAase, periodate and trypsin, but is susceptible to pronase digestion.