Efflux-mediated fluoroquinolone resistance in the multidrug-resistant Pseudomonas aeruginosa clinical isolate PA7: identification of a novel MexS variant involved in upregulation of the mexEF-oprN multidrug efflux operon

The emergence of multidrug-resistant Pseudomonas aeruginosa has become a serious problem in medical settings. P. aeruginosa clinical isolate PA7 is resistant to fluoroquinolones, aminoglycosides, and most -lactams but not imipenem. In this study, enhanced efflux-mediated fluoroquinolone resistance of PA7 was shown to reflect increased expression of two resistance nodulation cell division (RND) -type multidrug efflux operons, mexEF-oprN and mexXY-oprA. Such a clinical isolate has rarely been reported because MexEF-OprN-overproducing mutants often increase susceptibility to aminoglycosides apparently owing to impairment of the MexXY system. A mutant of PA7 lacking three RND-type multidrug efflux operons (mexAB-oprM, mexEF-oprN, and mexXY-oprA) was susceptible to all anti-pseudomonas agents we tested, supporting an idea that these RND-type multidrug efflux transporters are molecular targets to overcome multidrug resistance in P. aeruginosa. mexEF-oprN-upregulation in P. aeruginosa PA7 was shown due to a MexS variant harboring the Valine-155 amino acid residue. This is the first genetic evidence shown that a MexS variant causes mexEF-oprN-upregulation in P. aeruginosa clinical isolates

Cost-effectiveness Analysis of CO2 Reduction in the Automobile Sector

Various problems relating to energy and the environment clearly exist, such as global warming and a steep rise in the price fossil fuels, and resources. These problems should be addressed in the medium term or long run. As for the abatement of greenhouse gas emission, active discussions have been held on the stage of world politics to achieve the long-term goal. Although various approaches have been proposed by several research institutions and countries, sufficient studies have not yet been conducted on the roles of individual countries and sectors. Specifically, in the automotive transportation sector wherein oil demand and CO2 emissions are estimated to rise in the future with the marked progress of motorization in developing countries, it is increasingly important to study these subjects. We focused on the automotive transportation sector and studied the CO2 abatement potential and its cost performance in this sector. This article reports the results of the study.energy and the environment, Climate change, automotive transportation

One Argonaute family member, Eif2c2 (Ago2), is essential for development and appears not to be involved in DNA methylation

AbstractTo elucidate the epigenetic role of RNAi in mammals, we disrupted the gene for Eif2c2 (Ago2), which works as the sole slicer of RNAi in the Argonaute family. In mice, disruption of Eif2c2 leads to embryonic lethality early in development after the implantation stage. This phenotype is completely different from that in a previous report, but somewhat similar to the disruption of Dicer1, another important component of RNAi. We also show that Eif2c2 is not required for the maintenance of DNA methylation in imprinted genes, centromeric repeats, and Xist. This suggests that developmental defects in the Eif2c2-deficient mouse are caused not at the transcriptional level, but rather at the posttranscriptional level through the miRNA–protein complex

ヒラアオノリ及びヒトエグサのプロトプラストとスサビノリのプロトプラストとの高頻度異種融合の方法について

Low hetero-fusion frequencies between Porphyra yezoensis and Enteromorpha compressa or P. yezoensis and Monostroma nitidum protoplasts were observed when these protoplasts were fused following either of electrofusion or polyethylene glycol (PEG) mediated fusion methods. Pretreatment of protoplasts with actinase E (0.15%, 22℃ for 1h) enhanced hetero-fusion frequency following both electrofusion and PEG methods. Maximum hetero-fusion frequencies were 7-8% when P. yezoensis and E. compressa protoplasts were treated with actinase E and electrically fused. Electrofusion was optimally achieved when protoplasts were aligned at 25V (AC) for 20s and induced to fuse by a DC pulse of 250V for 25 μs. Electrofusion method was found not suitable for hetero-fusions between P. yezoensis and M. nitidum protoplasts; hetero-fusion frequencies were low (1-2%) although these protoplasts were treated with actinase E before electrofusion. Higher voltages to increase heterofusion frequency resulted in lysis of protoplasts. These difficulties were attributed to the differences in protoplast size of the fusion partners. PEG mediated fusion overcame these difficulties. Maximum hetero-fusion frequencies were 6-7% when P. yezoensis and M. nitidum protoplasts were treated with actinase E prior to PEG mediated fusion.スサビノリとヒラアオノリ,スサビノリとヒトエグサとの組み合わせで各々のプロトプラストを電気融合法またはポリエチレングリコール(PEG)法で融合したが,いずれの場合も融合の頻度は低かった。そこで,各プロトプラストをアクチナーゼE (0.15%, 22℃, 1時間)で前処理すると,電気融合法,PEG法のいずれの場合も異種融合頻度は高くなった。アクチナーゼE処理したスサビノリとヒラアオノリとの電気融合は,最高値7～8%となった。この電気融合率の最適条件は,高周波電圧(AC) 25V, 20sの印加によってチェーンが形成され,パルス電圧(DC) 250V, 20μsの印加によって融合が誘導された。電気融合法によるスサビノリとヒトエグサのプロトプラストの異種融合では,アクチナーゼEで前処理したプロトプラストの融合であっても,融合頻度は1～2%と低く,電気融合法が適さないことが分かった。異種融合の頻度を増すために,より高いパルス電圧をかけると,プロトプラストは破壊してしまった。これらの問題は,二種類のプロトプラストの大きさの違いによるものである。これらの問題を解決するために,スサビノリとヒトエグサとのあいだで,PEGによる異種融合を行うと,融合頻度は高くなった。アクチナーゼE処理したスサビノリとヒトエグサのプロトプラストの異種融合頻度は,PEG法によって最高値6～7%となった

Functional Blockade of E-Selectin in Tumor-Associated Vessels Enhances Anti-Tumor Effect of Doxorubicin in Breast Cancer

Chemotherapy is a mainstay of treatment for solid tumors. However, little is known about how therapy-induced immune cell infiltration may affect therapy response. We found substantial CD45+ immune cell density adjacent to E-selectin expressing inflamed vessels in doxorubicin (DOX)-treated residual human breast tumors. While CD45 level was significantly elevated in DOX-treated wildtype mice, it remained unchanged in DOX-treated tumors from E-selectin null mice. Similarly, intravenous administration of anti-E-selectin aptamer (ESTA) resulted in a significant reduction in CD45+ immune cell density in DOX-treated residual tumors, which coincided with a delay in tumor growth and lung metastasis in MMTV-pyMT mice. Additionally, both tumor infiltrating T-lymphocytes and tumor associated-macrophages were skewed towards TH2 in DOX-treated residual breast tumors; however, ESTA suppressed these changes. This study suggests that DOX treatment instigates de novo intratumoral infiltration of immune cells through E-selectin, and functional blockade of E-selectin may reduce residual tumor burden as well as metastasis through suppression of TH2 shift

A quantitative comparison of fish assemblage between amacroalgae bed and an adjoining sandy beach in the central Seto Inland Sea

植生の有無が魚類群集に与える影響を明らかにすることを目的として，瀬戸内海中央部の無人島（小久野島）の東岸において隣接するガラモ場と砂浜の魚類相調査を実施した。ガラモ場と砂浜に10m四方（面積100m2）の調査区画を各4ヶ所設定し，季節に1回の頻度で（2006年8月，11月，2007年2月，5月）小型巻網（目合い4mm）を用いて区画内の魚類をすべて採集した。一年間の調査により，ガラモ場で20種以上1,397個体，砂浜で17種以上902個体の魚類が採集された。個体数にもとづく優占種（上位3種）は，ガラモ場ではシロメバル，ヒメハゼ，ハオコゼ，砂浜ではヒメハゼ，ボラ，スジハゼ，湿重量にもとづく優占種は，ガラモ場ではシロメバル，ハオコゼ，キュウセン，砂浜ではヒメハゼ，シロギス，ボラであった。100m2あたりの出現種数，個体密度，バイオマスはいずれもガラモ場において大きな季節変動を示した。8月にはガラモ場における種数が砂浜よりも有意に多かった。ガラモ場においては，ホンダワラ類の繁茂期である2－5月にシロメバル仔稚魚の来遊にともなう個体密度とバイオマスの急増が認められた。Biological and physical surveys were conducted at amacloalgae bed (MB) and a sandy beach (SB) off an inhabited island in the central Seto Inland Sea, Japan, from August 2006 tomay 2007 in order to detect the effect of vegetation on fish assemblage. Fish were collected using a seine net (2m in height, 3mm in mesh aperture) at four separate locations within MB and SB during a tidal level between 70-130 cm in daytime on 4 Aug. and 16 Nov. 2006 and 19 Feb. and 2 May 2007. A total of 1,397 and 902 fish were collected at MB and SB, respectively. The numerically dominant species were Sebastes cheni, Favonigobius gymnauchen and Hypodytes rubripinnis in MB and Favonigobius gymnauchen, mugil cephalus cephalus and Acentrogobius pflaumii in SB. Weight-based dominant species were Sebastes cheni, Hypodytes rubripinnis and Halichoeres poecilopterus in MB and Favonigobius gymnauchen, Sillago japonica and Mugil cephalus cephalus. Seasonal fluctuation in number of fish species, fish abundance and biomass in MB were larger than those in SB. The number of fish species in August in MB was significantly higher than that in SB. Fish abundance and biomass in MB abruptly increased fromFebruary to May due to immigration of S. cheni larvae and juveniles

Estimation of catch efficiency of a small seine for larval and juvenile Japanese sea bass, Lateolabrax japonicus, in the Ohta estuary

河口域における魚類群集の主要構成者であるスズキ仔稚魚に対する小型曳き網（幅2.3m，高さ1m）の採集効率を，地曳き網（幅16m，高さ1m）による採集結果と比較することにより推定した。2008年3月21日と4月7日に太田川放水路感潮域において合計15回の曳網を行い，合計1,502個体（標準体長14.5－24.0mm）のスズキ仔稚魚を採集した。地曳き網の網目からの逸出が生じる体長16mm未満と，個体密度が著しく低下する23mm以上については解析対象とせず，地曳き網による採集効率を100％と仮定した。体長1mmごとに区分した分布密度を採集具間で比較した結果，小型曳き網による体長16mm以上18mm未満のスズキ仔稚魚採集効率は約100％と推定された。体長18mm以上23mm未満では採集効率（C, ％）が体長（L, mm）に比例して直線的に減少した（C=－17.2*L+388.8，n=11，r2=0.77，p=0.0004）。In order to estimate catch efficiency of a small seine (1.0 by 2.3 m, 2 mm mesh aperture) for larval and juvenile Japanese sea bass Lateolabrax japonicus, results from experimental hauls of the small seine were compared with those from a large seines (1.0 by 16 m, 2.5 mm mesh aperture) in the Ohta Diversion Channel on March 21 and April 7, 2008. A total of 1,502 Japanese sea bass, ranging between 14.5 and 24.0 mm in standard length were collected. Data of fish <15.9 mm was excluded from the analysis since extrusion of these fish through the mesh of the large seine was possible. Comparison of the Japanese sea bass abundance at lengths between the small and large seines revealed that the catch efficiency of the small seine for Japanese sea bass <18.0 mm was approximately 100%. The catch efficiency decreased with the increase in fish body length between 18.0 and 22.9 mm. A linear model was fitted to the relationship between the catch efficiency (C, %) and body length (L, mm): C=－17.2*L+388.8 (n=11, r2=0.77, p=0.0004). Catch efficiency was not estimated for Japanese sea bass ＞ 23 mm since their abundance was quite low in the surveyed area probably due to migration to downriver or sea areas, which are considered as habitats for the following life stages

Separation of Lanthanoids by SiO 2 -P Adsorbent Impregnated with Extractants -13103

ABSTRACT The adsorption and separation properties of lanthanoids (Ln) were investigated for the mutual separation of trivalent minor actinoids (MA) by using different adsorbents of hydrophobic extractant/SiO 2 -P in solutions of hydrophilic extractant/HNO 3 . The synergistic effect by use of the hydrophobic and hydrophilic extractants was evaluated by batch and column experiments. The results of batch expariments showed the synergistic effect which lowered the K d values of Ln. In column experiments, effective mutual separation between Nd and Sm was demonstrated. These results suggest that the mutual separation between Am and Cm is possible because the K d values of Am and Cm are probably similar to those of Nd and Sm