Effects of positively charged arginine residues on membrane pore forming activity of Rev–NIS peptide in bacterial cells

AbstractHere, we investigated antibacterial effects of Rev–NIS and suggested the role of positively charged amino acids on membrane pore forming activity of the peptide in bacterial cells, by synthesizing two analogs, Anal R and Anal S. Based on the amphipathic property of Rev–NIS, Anal R and Anal S were designed by substituting E1 and L3 to R and L3 to S, respectively. The circular dichroism (CD) spectroscopy showed that Anal R and Anal S have the same conformation of Rev–NIS, with a significant fraction of helical structure. In succession, the antibacterial susceptibility testing showed that Rev–NIS and its analogs possessed significant activities (Anal R>Rev–NIS>Anal S), without hemolytic effects, against bacterial pathogens including antibiotics-resistant strains. Moreover, the membrane studies, 3,3′-dipropylthiadicarbocyanine iodide (diSC35) staining and FITC-dextran (FD) leakage assay demonstrated that the analogs as well as Rev–NIS acted on the bacterial membranes and potently made pores, with the hydrodynamic radius between 1.4nm and 2.3nm. Especially, Anal R made larger pores than other peptides, with the radius between 2.3nm and 3.3nm. These results also corresponded to the result of antibacterial susceptibility testing. In summary, this study indicates that the two arginine residues are more influential than the hydrophobicity or the helicity, regarding the molecular activity of the peptide, and finally suggests that Anal R peptide may be applied to novel antibacterial agents

Antifungal effect and pore-forming action of lactoferricin B like peptide derived from centipede Scolopendra subspinipes mutilans

AbstractThe centipede Scolopendra subspinipes mutilans has been a medically important arthropod species by using it as a traditional medicine for the treatment of various diseases. In this study, we derived a novel lactoferricin B like peptide (LBLP) from the whole bodies of adult centipedes, S. s. mutilans, and investigated the antifungal effect of LBLP. LBLP exerted an antifungal and fungicidal activity without hemolysis. To investigate the antifungal mechanism of LBLP, a membrane study with propidium iodide was first conducted against Candida albicans. The result showed that LBLP caused fungal membrane permeabilization. The assays of the three dimensional flow cytometric contour plot and membrane potential further showed cell shrinkage and membrane depolarization by the membrane damage. Finally, we confirmed the membrane-active mechanism of LBLP by synthesizing model membranes, calcein and FITC-dextran loaded large unilamellar vesicles. These results showed that the antifungal effect of LBLP on membrane was due to the formation of pores with radii between 0.74nm and 1.4nm. In conclusion, this study suggests that LBLP exerts a potent antifungal activity by pore formation in the membrane, eventually leading to fungal cell death

Prognosis of Elderly Patients with Advanced Gastric Cancer without Serosal Invasion

Introduction: The impact of age on the prognosis of patients with gastric cancer is controversial. This study aimed to investigate the clinicopathologic features and prognosis of elderly, advanced gastric cancer patients without serosal invasion compared to their younger counterparts. Materials and Methods: We retrospectively evaluated 43 elderly patients with advanced gastric cancer without serosal invasion. The clinicopathologic findings were compared between the elderly (age >70 years) and young (age <36 years) patients. Results: Significantly higher numbers of elderly patients had tumors with differentiated histology, whereas more young patients had tumors with undifferentiated histology (P < 0.01). Curability (risk ratio, 3.122; confidence interval, 1.242-4.779; P < 0.001) was an independent prognostic factor of survival. The 5-year survival rates were not significantly different between the elderly and the young patients according to the absence of serosal invasion (80.0% vs 77.9%; P = 0.654) and undergoing curative resection (82.0% vs 78.9%; P = 0.312). Meanwhile, among the elderly patients, those who underwent curative resection had a better survival rate than those with non-curative resection (82.0% vs 67.8%; P < 0.001). Conclusion: Elderly patients with advanced gastric cancer without serosal invasion do not have a worse prognosis than their younger counterparts, indicating that age does not impact the prognosis of advanced gastric cancer. The important prognostic factor was whether the patients underwent curative resection

BIM-Based Construction Information Management Framework for Site Information Management

Projects in the construction industry are becoming increasingly large and complex, with construction technologies, methods, and the like developing rapidly. Various different types of information are generated by construction projects. Especially, a construction phase requires the input of many resources and generates a diverse set of information. While a variety of IT techniques are being deployed for information management during the construction phase, measures to create databases of such information and to link these various different types of information together are still insufficient. As such, this study aims to suggest a construction information database system based on BIM technology to enable the comprehensive management of site information generated during the construction phase. This study analyzed the information generated from construction sites and proposed a categorization system for structuring the generated information, along with a database model for storing such structured information. Through such efforts, it was confirmed that such a database system can be used for accumulating and using construction information; it is believed that, in the future, the continual accumulation and management of construction information will allow for corporate-level accumulation of knowledge as opposed to the individual accumulation of know-how

Disentangling The Effects Of The Employee Benefits On Employee Productivity

This study aimed to investigate the effects of employee benefits on employee productivity. There are conflicting views, positive and negative, with regard to the effect of employee benefits on employee productivity. Overall, we found that employee benefits have a positive impact on employee productivity through the embodied effect (direct effect). Specifically, according to a workplace panel survey in Korea conducted between 2005 and 2009, an increase of one unit in employee benefits leads to an increase of employee productivity by about 7.9%. In addition, we found that such effect is stronger in the manufacturing industry than in the non-manufacturing industry. Although there is no difference in the effect of benefits between large firms and small and medium-sized firms, the labor-embodied effect is stronger in large firms, and the capital-embodied effect is salient in small and medium-sized firms

Status of MgB2 superconducting wires at Sam Dong

MgB2 superconducting wires have remarkable potential as cost-effective materials for transformers, generators, power transmission, and superconducting magnetic energy storage to enable highly efficient power-grid networks for sustainable development. Herein, we report multifilamentary MgB2 wires with variously designed architectures that have been developed by Sam Dong Co., Ltd. The customized manufacturing process can also produce long-length pieces up to 3 km in length, indispensable in constructing large-scale devices, including cables. Based on this progress, we will continue to develop high-performance MgB2 wires and related superconducting technologies