日本に侵入した絶対単為生殖型ミジンコ（Daphnia pulex）の適応放散: 表現形質の変異と可塑性の生態学的意義

Tohoku University占部城太郎課

Pretreatment of microcrystalline cellulose in organic electrolyte solutions for enzymatic hydrolysis

<p>Abstract</p> <p>Background</p> <p>Previous studies have shown that the crystalline structure of cellulose is negatively correlated with enzymatic digestibility, therefore, pretreatment is required to break down the highly ordered crystalline structure in cellulose, and to increase the porosity of its surface. In the present study, an organic electrolyte solution (OES) composed of an ionic liquid (1-allyl-3-methylimidazolium chloride ([AMIM]Cl)) and an organic solvent (dimethyl sulfoxide; DMSO) was prepared, and used to pretreat microcrystalline cellulose for subsequent enzymatic hydrolysis; to our knowledge, this is the first time that this method has been used.</p> <p>Results</p> <p>Microcrystalline cellulose (5 wt%) rapidly dispersed and then completely dissolved in an OES with a molar fraction of [AMIM]Cl per OES (χ _[AMIM]Cl) of greater than or equal to 0.2 at 110°C within 10 minutes. The cellulose was regenerated from the OES by precipitation with hot water, and enzymatically hydrolyzed. As the χ _[AMIM]Clof the OES increased from 0.1 to 0.9, both the hydrolysis yield and initial hydrolysis rate of the regenerated cellulose also increased gradually. After treatment using OES with χ _[AMIM]Clof 0.7, the glucose yield (54.1%) was 7.2 times that of untreated cellulose. This promotion of hydrolysis yield was mainly due to the decrease in the degree of crystallinity (that is, the crystallinity index of cellulose I).</p> <p>Conclusions</p> <p>An OES of [AMIM]Cl and DMSO with χ _[AMIM]Clof 0.7 was chosen for cellulose pretreatment because it dissolved cellulose rapidly to achieve a high glucose yield (54.1%), which was only slightly lower than the value (59.6%) obtained using pure [AMIM]Cl. OES pretreatment is a cost-effective and environmentally friendly technique for hydrolysis, because it 1) uses the less expensive OES instead of pure ionic liquids, 2) shortens dissolution time, 3) requires lower energy for stirring and transporting, and 4) is recyclable.</p

骨科择期手术患者压疮危险因素的研究

Objectives：The purposes of the study were to investigate the incidence of pressure ulcer of orthopedics patients undergoing selective operation, and to identify the risk factors of pressure ulcer.Methods: A prospective cohort study was employed in this study. Data were collected concerning the general characteristics as well as preoperative, intraoperative and postoperative indicators probable to induce pressure ulcer and then analyzed in view of the risk factors of pressure ulcer. Results: (1) Pressure ulcers developed in thirty five patients (10.1%) on day 0 and the first 3 days following surgery; (2) age, hemoglobin, lymphocyte and getting up late for the first time after surgery were significantly associated with the occurrence of pressure ulcers (odds ratio 1.068,  0.948, 0.293, 1.019, respectively).Conclusions: (1) Patients have higher risk of developing pressure ulcer after operation, the critical period beginning from the operation day to the 3rd day after operation. (2) The age older, the later getting up for the first time after surgery, the liable it is for the patients to develop pressure ulcer postoperatively.目的 调查骨科择期手术后患者压疮的发生率，分析术后压疮发生的危险因素。方法 采用前瞻性队列研究的方法，样本采用便利取样。记录患者的一般资料、术前、术中和术后可能与压疮发生有一定关系的各项指标，对骨科手术后患者的压疮危险因素进行分析。结果 （1）共35例患者发生了压疮，发生率为10.1%；术后皮肤出现异常的时间均在手术当天至手术后1～3天内；（2）高龄、术前低淋巴细胞总数、术前低血红蛋白含量和术后首次下地时间晚是骨科择期手术后患者发生压疮的危险因素，OR值分别为1.068、0.948、0.293、1.019。结论 （1）骨科择期手术后患者是院内压疮发生的高危人群，其中手术当天至手术后第3天为术后压疮预防的关键时期；（2）年龄越大、术前血红蛋白含量、淋巴细胞总数水平越低及手术后首次下地时间越晚，术后发生压疮的可能性就越大

Poly[[[diaqua­sodium]-μ3-5-carb­oxy-2-ethyl-1H-imidazole-4-carboxyl­ato-κ4 N 3,O 4:O 5:O 5] monohydrate]

In the title complex, {[Na(C7H7N2O4)(H2O)2]·H2O}n, the NaI atom exhibits a distorted octa­hedral geometry and is six-coordinated in an NO5 environment. The equatorial plane is defined by three O atoms and one N atom from two distinct 5-carb­oxy-2-ethyl-1H-imidazole-4-carboxyl­ate (H2EIDC) ligands and one coordinated water mol­ecule, and the apical sites are occupied by one carboxyl O atom from one H2EIDC ligand and one O atom from the other coordinated water mol­ecule. The NaI atoms are linked by H2EIDC ligands, generating an infinite double chain along the a axis. These chains are further connected via O—H⋯O and N—H⋯O hydrogen bonds into a three-dimensional supra­molecular network

Interactions among Lung Cancer Cells, Fibroblasts, and Macrophages in 3D Co-Cultures and the Impact on MMP-1 and VEGF Expression

In vitro cell-based models of lung cancer are frequently employed to study invasion and the mechanisms behind metastasis. However, these models often study only one cell type with two-dimensional (2D) monolayer cell cultures, which do not accurately reflect the complexity of inflammation in vivo. Here, a three-dimensional (3D) cell co-culture collagen gel model was employed, containing human lung adenocarcinoma cells (HCC), human lung fibroblast cells (MRC-5), and macrophages. Cell culture media and cell images were collected, and matrix metalloproteinase-1 (MMP-1) and vascular endothelial growth factor (VEGF) production was monitored under different cell culture conditions. We found that simulating hypoxia and/or serum starvation conditions induced elevated secretion of VEGF in the 3D co-culture model in vitro, but not MMP-1;the morphology of HCC in the 2D versus the 3D co-culture system was extremely different. MMP-1 and VEGF were secreted at higher levels in mixed cell groups rather than mono-culture groups. Therefore, incorporating lung cancer cells, fibroblasts, and macrophages may better reflect physiological metastasis mechanisms compared to mono-culture systems. Tumour stromal cells, macrophages, and fibroblast cells may promote invasion and metastasis, which also provides a new direction for the design of therapies targeted at destroying the stroma of tumor tissues

Magnetosome Gene Duplication as an Important Driver in the Evolution of Magnetotaxis in the Alphaproteobacteria

The evolution of microbial magnetoreception (or magnetotaxis) is of great interest in the fields of microbiology, evolutionary biology, biophysics, geomicrobiology, and geochemistry. Current genomic data from magnetotactic bacteria (MTB), the only prokaryotes known to be capable of sensing the Earth’s geomagnetic field, suggests an ancient origin of magnetotaxis in the domain Bacteria. Vertical inheritance, followed by multiple independent magnetosome gene cluster loss, is considered to be one of the major forces that drove the evolution of magnetotaxis at or above the class or phylum level, although the evolutionary trajectories at lower taxonomic ranks (e.g., within the class level) remain largely unstudied. Here we report the isolation, cultivation, and sequencing of a novel magnetotactic spirillum belonging to the genus Terasakiella (Terasakiella sp. strain SH-1) within the class Alphaproteobacteria. The complete genome sequence of Terasakiella sp. strain SH-1 revealed an unexpected duplication event of magnetosome genes within the mamAB operon, a group of genes essential for magnetosome biomineralization and magnetotaxis. Intriguingly, further comparative genomic analysis suggests that the duplication of mamAB genes is a common feature in the genomes of alphaproteobacterial MTB. Taken together, with the additional finding that gene duplication appears to have also occurred in some magnetotactic members of the Deltaproteobacteria, our results indicate that gene duplication plays an important role in the evolution of magnetotaxis in the Alphaproteobacteria and perhaps the domain Bacteria

Phase evolution of Ce-based heavy-fermion superconductors under pressure: a combined DFT+DMFT and effective-model description

In typical Ce-based heavy-fermion superconductors, superconducting (SC) phases emerge or can be tuned in proximity to the antiferromagnetic (AF) quantum critical point (QCP), but so far the explicit phase-evolution process and the coexistence of superconductivity and AF order near the QCP remain lack of understanding. Here, by combing DFT+DMFT with effective-model calculations, we provide a theoretical description for Ce-based SC compounds under pressure. Firstly, DFT+DMFT calculations for the normal states reveal that the Kondo hybridizations are significantly enhanced, while the initially localized $f$ electrons eventually become fully itinerant via a localized-itinerant crossover. In this context, we construct an effective model with tunable parameters under pressure, and show that the interplay of magnetic correlation and Kondo hybridization can drive successive transitions, from AF phase to AF+SC coexisting phase, then to paramagnetic SC phase via an AF transition which corresponds to the QCP, and finally to Kondo paramagnetic phase through a SC transition driven by localized-itinerant crossover. Our study gives a proper explanation for the pressure-induced magnetic QCP and SC transition, and for the phase-evolution process under pressure in typical Ce-based superconductors, and may also help to understand the SC states emerging around the ferromagnetic quantum transition points in uranium-based superconductors.Comment: 13 pages, 11 figure

PLGA-based gene delivering nanoparticle enhance suppression effect of miRNA in HePG2 cells

The biggest challenge in the field of gene therapy is how to effectively deliver target genes to special cells. This study aimed to develop a new type of poly(D,L-lactide-co-glycolide) (PLGA)-based nanoparticles for gene delivery, which are capable of overcoming the disadvantages of polyethylenimine (PEI)- or cationic liposome-based gene carrier, such as the cytotoxicity induced by excess positive charge, as well as the aggregation on the cell surface. The PLGA-based nanoparticles presented in this study were synthesized by emulsion evaporation method and characterized by transmission electron microscopy, dynamic light scattering, and energy dispersive spectroscopy. The size of PLGA/PEI nanoparticles in phosphate-buffered saline (PBS) was about 60 nm at the optimal charge ratio. Without observable aggregation, the nanoparticles showed a better monodispersity. The PLGA-based nanoparticles were used as vector carrier for miRNA transfection in HepG2 cells. It exhibited a higher transfection efficiency and lower cytotoxicity in HepG2 cells compared to the PEI/DNA complex. The N/P ratio (ratio of the polymer nitrogen to the DNA phosphate) 6 of the PLGA/PEI/DNA nanocomplex displays the best property among various N/P proportions, yielding similar transfection efficiency when compared to Lipofectamine/DNA lipoplexes. Moreover, nanocomplex shows better serum compatibility than commercial liposome. PLGA nanocomplexes obviously accumulate in tumor cells after transfection, which indicate that the complexes contribute to cellular uptake of pDNA and pronouncedly enhance the treatment effect of miR-26a by inducing cell cycle arrest. Therefore, these results demonstrate that PLGA/PEI nanoparticles are promising non-viral vectors for gene delivery