Characterization of Clonal Polyp Strains Established from Aurelia sp. Inhabiting the Seto Inland Sea of Japan

ミズクラゲ(Aurelia sp.)の生活環の中で，ポリプからストロビラを経てエフィラに形態変化する過程はストロビレーションと呼ばれる。ストロビレーションの分子機構の解明に向けて分子生物学的および生化学的研究を進めるために，瀬戸内海産のミズクラゲからポリプのクローン系統を7株確立した。実験室内でストロビレーションを誘導する条件を検討した結果，これらのクローン系統は，25℃から10℃への低温処理によって32- 42日でストロビレーションを開始し，indomethacin (25μM)の投与によって25℃条件下で4-8日でストロビレーションを開始した。また，短期間だけ低温処理をおこなう飼育実験の結果，ストロビレーションは一旦開始すると低温条件下でなくても正常に進行し完了することが明らかになった。さらに，分子系統解析の結果，今回確立したクローン系統がAurelia sp.1(Dawson et al., 2005)であることが示唆された。In the life cycle of Aurelia sp., the transition from polyp to strobila/ephyra is called“strobilation”. To study the molecular mechanisms of strobilation with molecular biological and biochemical approaches, we established 7 clonal polyp strains from Aurelia sp. inhabiting the Seto Inland Sea of Japan. In laboratory condition, the clonal strains started strobilation in 32 - 42 days by a temperature change from 25˚C to 10˚C, or in 4 - 8 days at 25˚C by administration of indomethacin (25 μM). The experiments of short-term low-temperature treatments revealed that strobilation proceeded to the end independently of temperature after strobilation had been initiated. Further, molecular phylogenetic analysis suggested that the clonal strains could be Aurelia sp. 1 (Dawson et al., 2005).本研究は，平成20年度広島大学後援会・教育研究一般助成および平成20年度広島大学大学院生物圏科学研究科・研究科長裁量経費研究助成の支援のもとで実施されたものである

Neuromedin U-deficient rats do not lose body weight or food intake

Studies in genetically modified mice establish that essential roles of endogenous neuromedin U (NMU) are anorexigenic function and metabolic regulation, indicating that NMU is expected to be a potential target for anti-obesity agents. However, in central administration experiments in rats, inconsistent results have been obtained, and the essential role of NMU energy metabolism in rats remain unclear. This study aims to elucidate the role of endogenous NMU in rats. We generated NMU knockout (KO) rats that unexpectedly showed no difference in body weight, adiposity, circulating metabolic markers, body temperature, locomotor activity, and food consumption in both normal and high fat chow feeding. Furthermore, unlike reported in mice, expressions of Nmu and NMU receptor type 2 (Nmur2) mRNA were hardly detectable in the rat hypothalamic nuclei regulating feeding and energy metabolism, including the arcuate nucleus and paraventricular nucleus, while Nmu was expressed in pars tuberalis and Nmur2 was expressed in the ependymal cell layer of the third ventricle. These results indicate that the species-specific expression pattern of Nmu and Nmur2 may allow NMU to have distinct functions across species, and that endogenous NMU does not function as an anorexigenic hormone in rats

Is it practical to determine the therapeutic strategy for breast cancer by evaluating pathological findings in core needle biopsy specimens?

Background; Core needle biopsy (CNB) specimens have been widely used not only for the diagnosis of breast cancer, but also for assessing biomarkers, including lymphovascular invasion (ly and v), nuclear grading, the estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER-2) and Ki-67. We herein compared the pathological biomarkers of ER+/HER2- invasive breast cancers in CNB with those in the subsequent surgical specimens.　Methods; Patients with ER+/HER2- invasive breast cancer who presented to our department from August 2011 to July 2013 who had CNB and subsequent surgery were included. Lymphovascular invasion (ly, v) and nuclear grading were determined by hematoxylin and eosin staining, and the ER, PgR, HER-2, and Ki-67 status were evaluated by immunohistochemistry.　Results; The concordance rates between CNB and surgical specimens for the ly, v, nuclear grading, ER and PgR were 2.4%, 2.9%, 63.0%, 96.4% and 82.1%, respectively. Lymphovascular invasion and nuclear grading tended to be underestimated with CNB in discordant cases. The Ki-67 labeling index in CNB specimens was strongly correlated with that in surgical specimens (correlation coefficient 0.75, p<0.0001). Consequently, there was a reasonable level of agreement between CNB and surgical specimens for surrogate subtyping (82.1%).　Conclusions; CNB provided reliable information on the expression of hormone receptors, Ki-67 in ER+/HER2- invasive breast cancers. However, because of the substantial discordance between CNB and surgical specimens, the status of lymphovascular invasion and nuclear grading should not be concluded based on CNB specimens

Molecular analysis of the BCR-ABL1 kinase domain in chronic-phase chronic myelogenous leukemia treated with tyrosine kinase inhibitors in practice: Study by the Nagasaki CML Study Group

An appropriate trigger for BCR-ABL1 mutation analysis has not yet been established in unselected cohorts of chronic-phase chronic myelogenous leukemia patients. We examined 92 patients after 12 months of tyrosine kinase inhibitor (TKI) treatment in Nagasaki Prefecture, Japan. Univariate analysis revealed that significant factors associated with not attaining a major molecular response (MMR) were the presence of the minor BCR-ABL1 fusion gene, a low daily dose of TKI, and the emergence of BCR-ABL1 kinase domain mutations conferring resistance to imatinib. Factors associated with the loss of sustained MMR were a low daily dose of TKI and the emergence of alternatively spliced BCR-ABL1 mRNA with a 35-nucleotide insertion. Taken together, our results suggest that the search for BCR-ABL1 mutations should be initiated if patients have not achieved MMR following 12 months of TKI treatment

Blood mercury level after administration of methyl mercury to an irritable bowel syndrome model rat using the improved method of cold vapor atomic absorption spectrophotometry

[Abstract] The number of people suffering from irritable bowel syndrome (IBS) continues to increase. It is thought that in IBS the absorption of substances from food differs from that in normal people. The aim of the present study was to clarify the difference in absorption of mercury between normal and IBS using a model rat. Cold vapor atomic absorption spectrophotometry for mercury measurement can measure the inorganic mercury level, but not the organic mercury level. An improved analytical method for the measurement of mercury was developed. Indomethacin was orally administered to rats to make an IBS model rat. When methyl mercury was p.o. administered to rats on the day after indomethacin administration, the blood mercury level did not differ from the control group until six hours later. However, when methyl mercury was administered to rats two days after, the blood mercury level was observed to be higher than that of the control group from 1 hour to 6 hours. From the present results, we concluded that IBS sufferers may absorb a lot of mercury from meals in comparison with healthy people

Use of Bacterial γ-Glutamyltranspeptidase for Enzymatic Synthesis of γ-d-Glutamyl Compounds

An enzymatic method for synthesizing various γ-d-glutamyl compounds efficiently and stereospecifically involving bacterial γ-glutamyltranspeptidase (EC 2.3.2.2) with d-glutamine as a γ-glutamyl donor was developed. With d-glutamine as a γ-glutamyl donor instead of l-glutamine in γ-glutamyltaurine synthesis, by-products such as γ-glutamylglutamine and γ-glutamyl-γ-glutamyltaurine were not synthesized and the yield of γ-glutamyltaurine dramatically increased from 25 to 71%. It was also shown that the purification could be simplified without these γ-glutamyl by-products. The possibility of synthesizing various γ-d-glutamyl compounds was also shown

Sphingomyelin synthase 1 supports two steps of rubella virus life cycle

Summary: Our knowledge of the regulatory mechanisms that govern the replication of the rubella virus (RV) in human cells is limited. To gain insight into the host-pathogen interaction, we conducted a loss-of-function screening using the CRISPR-Cas9 system in the human placenta-derived JAR cells. We identified sphingomyelin synthase 1 (SGMS1 or SMS1) as a susceptibility factor for RV infection. Genetic knockout of SGMS1 rendered JAR cells resistant to infection by RV. The re-introduction of SGMS1 restored cellular susceptibility to RV infection. The restricted step of RV infection was post-endocytosis processes associated with the endosomal acidification. In the late phase of the RV replication cycle, the maintenance of viral persistence was disrupted, partly due to the attenuated viral gene expression. Our results shed light on the unique regulation of RV replication by a host factor during the early and late phases of viral life cycle