Resetting of the circannual rhythm of the varied carpet beetle Anthrenus verbasci by low-temperature pulses

The varied carpet beetle Anthrenus verbasci L. has a circannual pupation rhythm and pupates in the spring in the wild. The change in photoperiod acts as a predominant zeitgeber for this rhythm. However, it is unclear whether the change in ambient temperature acts as a zeitgeber. The present study examines the effects of low-temperature pulses on this circannual rhythm by exposing larvae kept under constant short-day conditions (LD 12 : 12 h) at 20°C to a lower temperature of 15, 10 or 5°C for 8 or 12 weeks at various phases. Larval development and pupation are suppressed during exposure to low temperature, with this pupation being induced in sufficiently grown larvae within 2 months of a return to 20°C. These results are attributed to the exogenous suppression and stimulation of pupation, rather than being related to the circannual rhythm (i.e. masking of the circannual rhythm by temperature). Furthermore, long-term observations demonstrate the existence of phase-dependent phase shifts of circannual rhythm as a result of low-temperature pulses. Circannual phase response curves to low temperature are constructed on the basis of the phase shifts obtained. A low-temperature pulse as a winter signal can reset the circannual rhythm of A. verbasci. It is probable that both temperature and photoperiod play a role in the entrainment of this circannual rhythm to a natural year

Analysis of the Brownian Motion by Elementary School Students

To stimulate the intellectual curiosity of elementary school students, we conducted a workshop in distance education aimed at exploring the microscopic world inside a cell. In this workshop, elementary school students motivated to learn more on the subject of science analyzed movies of the Brownian motion of micrometer-sized particles suspended in water, using an open-source software, Tracker. These students then performed two-dimensional(2D)-random walk experiments using a dice game sheet to examine the physical mechanism of Brownian motion. After the workshop, we conducted a questionnaire-based survey. Many participants answered that the contents were difficult but interesting, suggesting that our workshop was very efficient to stimulate the curiosity of motivated students.Comment: 16 pages, 10 figures, the following article has been submitted to The Physics Teache

Apatite formation on electrochemically modified surface of hafnium metal in simulated body environment

Biomedical application of Hf for hard tissue repair may be expanded if it can be imparted with bone-bonding ability. Apatite formation in the body is required for artificial materials to bond to bone. We have shown that apatite can form on NaOH- and heat-treated Hf in simulated body fluid, although the degree of apatite formation is not high. In this study, we investigated apatite formation on surface-modified Hf metal in simulated body fluid. Hf substrates were soaked in NH4F solution or electrochemically polarized in H2SO4 or NH4F solution, followed by heating at 600°C. The sample soaked or cathodically polarized in NH4F solution had porous structure, and the anodically polarized sample had nanotube aggregates on its surface. F was incorporated into the sample polarized in NH4F solution, but not the sample merely soaked in the solution. NH4F was more effective than H2SO4 in facilitating apatite formation. Remarkably, the sample soaked in NH4F solution had the highest apatite-forming ability. Its porous structure was considered to play a dominant role in apatite formation. Furthermore, there was little correlation between surface energy and apatite formation. Notably, NH4F treatment is more effective than the previously reported NaOH and heat treatments in promoting apatite formation

Phylogenetic Insights into RT and Vpx/Vpr

The efficiency of reverse transcription to synthesize viral DNA in infected cells greatly influences replication kinetics of retroviruses. However, viral replication in non-dividing cells such as resting T cells and terminally differentiated macrophages is potently and kinetically restricted by a host antiviral factor designated SAMHD1 (sterile alpha motif and HD-domain containing protein 1). SAMHD1 reduces cellular deoxynucleoside triphosphate (dNTP) pools and affects viral reverse transcription step. Human immunodeficiency virus type 2 (HIV-2) and some simian immunodeficiency viruses (SIVs) have Vpx or Vpr to efficiently degrade SAMHD1. Interestingly, the reverse transcriptase (RT) derived from HIV-1 that encodes no anti-SAMHD1 proteins has been previously demonstrated to uniquely exhibit a high enzymatic activity. It is thus not irrational to assume that some viruses may have acquired or lost the specific RT property to better adapt themselves to the low dNTP environments confronted in non-dividing cells. This adaptation process may probably be correlated with the SAMHD1-antagonizing ability by viruses. In this report, we asked whether such adaptive events can be inferable from Vpx/Vpr and RT phylogenetic trees overlaid with SAMHD1-degrading capacity of Vpx/Vpr and with kinetic characteristics of RT. Resultant two trees showed substantially similar clustering patterns, and therefore suggested that the properties of RT and Vpx/Vpr can be linked. In other words, HIV/SIVs may possess their own RT proteins to adequately react to various dNTP circumstances in target cells

Multimodality Imaging to Detect Vulnerable Plaque in Coronary Arteries and Its Clinical Application

Postmortem studies have described the association between the thin-cap fibroatheroma (TCFA) and the occurrence of acute coronary syndrome (ACS). Both noninvasive and invasive techniques have been refined and used as a research tool to visualize the plaque at a high risk of disruption. There has been a considerable effort to develop the imaging modalities that offer detailed visualization of coronary pathology and accurately predict the adverse cardiac outcomes. This chapter provides an overview of the current and experimental coronary imaging methods to detect vulnerable plaque and discuss the potential implication of multimodality imaging in clinical practice

Phylogenetic Analysis of Vpx/Vpr Expression

Viruses of human immunodeficiency virus type 2 (HIV-2) and some simian immunodeficiency virus (SIV) lineages carry a unique accessory protein called Vpx. Vpx is essential or critical for viral replication in natural target cells such as macrophages and T lymphocytes. We have previously shown that a poly-proline motif (PPM) located at the C-terminal region of Vpx is required for its efficient expression in two strains of HIV-2 and SIVmac, and that the Vpx expression levels of the two clones are significantly different. Notably, the PPM sequence is conserved and confined to Vpx and Vpr proteins derived from certain lineages of HIV-2/SIVs. In this study, Vpx/Vpr proteins from diverse primate lentiviral lineages were experimentally and phylogenetically analyzed to obtain the general expression picture in cells. While both the level and PPM-dependency of Vpx/Vpr expression in transfected cells varied among viral strains, each viral group, based on Vpx/Vpr amino acid sequences, was found to exhibit a characteristic expression profile. Moreover, phylogenetic tree analyses on Gag and Vpx/Vpr proteins gave essentially the same results. Taken together, our study described here suggests that each primate lentiviral lineage may have developed a unique expression pattern of Vpx/Vpr proteins for adaptation to its hostile cellular and species environments in the process of viral evolution

Osteocyte Network; a Negative Regulatory System for Bone Mass Augmented by the Induction of Rankl in Osteoblasts and Sost in Osteocytes at Unloading

Reduced mechanical stress is a major cause of osteoporosis in the elderly, and the osteocyte network, which comprises a communication system through processes and canaliculi throughout bone, is thought to be a mechanosensor and mechanotransduction system; however, the functions of osteocytes are still controversial and remain to be clarified. Unexpectedly, we found that overexpression of BCL2 in osteoblasts eventually caused osteocyte apoptosis. Osteoblast and osteoclast differentiation were unaffected by BCL2 transgene in vitro. However, the cortical bone mass increased due to enhanced osteoblast function and suppressed osteoclastogenesis at 4 months of age, when the frequency of TUNEL-positive lacunae reached 75%. In the unloaded condition, the trabecular bone mass decreased in both wild-type and BCL2 transgenic mice at 6 weeks of age, while it decreased due to impaired osteoblast function and enhanced osteoclastogenesis in wild-type mice but not in BCL2 transgenic mice at 4 months of age. Rankl and Opg were highly expressed in osteocytes, but Rankl expression in osteoblasts but not in osteocytes was increased at unloading in wild-type mice but not in BCL2 transgenic mice at 4 months of age. Sost was locally induced at unloading in wild-type mice but not in BCL2 transgenic mice, and the dissemination of Sost was severely interrupted in BCL2 transgenic mice, showing the severely impaired osteocyte network. These findings indicate that the osteocyte network is required for the upregulation of Rankl in osteoblasts and Sost in osteocytes in the unloaded condition. These findings suggest that the osteocyte network negatively regulate bone mass by inhibiting osteoblast function and activating osteoclastogenesis, and these functions are augmented in the unloaded condition at least partly through the upregulation of Rankl expression in osteoblasts and that of Sost in osteocytes, although it cannot be excluded that low BCL2 transgene expression in osteoblasts contributed to the enhanced osteoblast function

Single-amino acid mutation 66SR in Gag-matrix enhances viral single-cycle infectivity of R5-tropic HIV-1rmt

We recently constructed two rhesus macaque-tropic human immunodeficiency virus type 1 (HIV-1 rmt) clones with CXCR-4 or CCR5 tropism, but a CCR5-tropic HIV-1rmt clone grew more poorly than a CXCR4topic clone. It has been demonstrated that interaction between viral Gag-matrix (MA) and Env-gp41 cytoplasmic tail is important for virion-incorporation of Env. Concordantly, Gag-MA mutations (62QR and 66SR) that rescue defects in virion-incorporation of Env/viral replication were reported. In this study, we analyzed effects of these Gag-MA mutations on R5-tropic HIV-1rmt replication potentials. While introduction of 62QR into three HIV-1rmt clones tested reduced their multi-cycle replication ability in rhesus lymphocytes or abolish single-cycle infectivity for luciferase reporter cells, three R5-tropic HIV-1rmt clones carrying 66SR exhibited similar growth kinetics to those of their parental clones. One such clone, 66SR+5gtu, appeared to induce stronger cytopathic effects than parental clone 5gtu. We therefore investigated effects of 66SR mutation on viral replication in more detail. Single-cycle infectivity of 66SR+5gtu was enhanced relative to that of 5gtu, but 66SR+5gtu virion production was significantly decreased compared to the 5gtu level. Gag-MA 66SR mutation may be useful to improve growth potentials of the R5-tropic HIV-1rmt clones

ソシキ ニ オケル チュウシンセイ サイコウ キャリア ケイセイ ニ モタラス エイキョウ ニ ツイテ

　本研究は，現代において，Schein(1978) が提唱した組織の中心方向の移動が，個人のキャリア形成における心理状態にもたらす影響について改めて検討を行うものである．インタビュー調査により，中心方向への移動の停滞・接近・後退によって，キャリア形成に対する関心の高まりやポジティブな感情やネガティブな感情の想起が生じることが明らかとなった．企業組織における異動がキャリア形成における心理状態に影響することが明らかとなったことで，キャリア形成において企業組織が有する影響の一端が示された

カクチョウ サレタ キャリア ノ セキニン シャクド ノ カイハツ

本研究の目的は，市村(2017) にて提示した，拡張されたキャリアの責任概念の尺度開発を行うことである．そのために，尺度項目を作成するとともに，類似概念との弁別妥当性，基準連関妥当性，信頼性についての検証を行った．因子分析及び相関分析，階層的重回帰分析の結果から，弁別妥当性，基準連関妥当性，信頼性をそれぞれ十分に満たすことが示された