A "master" in base unpairing during isomerization of a promoter upon RNA polymerase binding

Isomerization of a closed to open complex of a promoter upon RNA polymerase binding involves base unpairing at the -10 region. After potassium permanganate sensitivity of unpaired thymine residues, we studied base unpairing at the -10 region during isomerization upon RNA polymerase binding at the P1 and P3 promoters of the gal operon. Substitution of adenine by 2-amino purine (2-AP) at the invariable A·T base pair at the -11 position of P1 and P3 prevented unpairing not only at that position but also at the other downstream positions, suggesting a "master" role of the adenine base at -11 of the template strand in overall base unpairing. 2-AP at -11 did not inhibit the formation of RNA polymerase·promoter complex and subsequent isomerization of the polymerase. Substitution of adenine by 2-AP at several other positions did not affect thymine unpairing. Changing the position of the amino group from C6 in adenine to C2 in 2-AP is mutational only at the master switch position, -11

Information Network Villages A community--focused digital divide reduction policy in rural Korea

This study examines South Korea's Information Network Village (INVIL) project as an exemplary policy of building sustainable communities through a digital divide policy implemented in small rural areas. INVIL project has three objectives: to close the digital gap between urban and rural areas, to create new sources of revenues from existing industries, and to build sustainable local communities. The conception was that rural digital divide can only be resolved by addressing deep rooted rural issues that influence the provision and adoption of ICT. While the INVIL programs may not remedy the gap in the short term, it provides a future vision to the communities. Due to this multi-layered and long term approach, the villages have been successful in narrowing the digital divide, not only in terms of access but also in effectively utilising broadband to enhance the local economy and building sustainable communities. This paper introduces the INVIL project, the plans and outcomes, as well as a qualitative evaluation of the process across a decade. Following a general description of the project, an in-depth case study of three successful INVILs is provided. The uniqueness of the program is that it emphasises investment in human capital rather than on infrastructure and includes a tailored vision of each local community. This motivates local residents to be active participants, which is the key to the success of the policy

Uterine and placental expression of TRPV6 gene is regulated via progesterone receptor- or estrogen receptor-mediated pathways during pregnancy in rodents

Transient receptor potential cation channel, subfamily V, member 6 (TRPV6) is an epithelial Ca2+ channel protein expressed in calcium absorbing organs. In the present study, we investigated the expression and regulation of uterine and placental TRPV6 during gestation in rodents. Uterine TRPV6 peaked at pregnancy day (P) 0.5, P5.5 and, P13.5 and was detected in uterine epithelium and glands of rats, while placental TRPV6 mRNA levels increased in mid-gestation. Uterine and placental TRPV6 mRNA levels in rats appear to cyclically change during pregnancy, suggesting that TRPV6 may participate in the implantation process. In addition, uterine TRPV6 mRNA is only expressed in placenta-unattached areas of the uterus, and uterine TRPV6 immunoreactivity was observed in luminal and glandular epithelial cells. In the placenta, TRPV6 was detected in the labyrinth and spongy zone. These results may indicate that TRPV6 has at least two functions: implantation of the embryo and maintenance of pregnancy. To investigate the pathway(s) mediating TRPV6 expression in rodents, anti-steroid hormone antagonists were injected prior to maximal TRPV6 expression. In rats, TRPV6 expression was reduced by RU486 (an anti-progesterone) through progesterone receptors, and ICI 182,780 (an anti-estrogen) blocked TRPV6 expression via estrogen receptors in mice. The juxtaposition of uterine and placental TRPV6 expressed in these tissues supports the notion that TRPV6 participates in transferring calcium ions between the maternal and fetal compartments. Taken together, TRPV6 gene may function as a key element in controlling calcium transport in the uterus between the embryo and the placenta during pregnancy

Intraosseous Hemangioma of the Middle Turbinate Misdiagnosed As a Nasal Polyp

Intraosseous hemangiomas account for 1% of all bone tumors and primarily originate from the vertebral column and skull bones. However, intraosseous hemangiomas of the nasal cavity are extremely rare. Here, we report a case of intraosseous hemangioma with a cavernous pattern arising from the middle turbinate that was preoperatively misdiagnosed as chronic rhinosinusitis with polyps. Except for nasal obstruction, there were no specific rhinologic symptoms. The tumor was excised en bloc by the endoscopic endonasal approach without preoperative embolization

Immobilized Polydiacetylene Lipid Vesicles on Polydimethylsiloxane Micropillars as a Surfactin-Based Label-Free Bacterial Sensor Platform

Accurate detection and sensing of bacteria are becoming increasingly important not only in microbiology but in a variety of fields including medicine, food, public health, and environmental science. However, even new rapid methods are not convenient enough. Here, we describe a simple and efficient label-free bacterial detection system using the polydiacetylene (PDA) liposomes immobilized on the 3D polydimethylsiloxane (PDMS) micropillars. Our system utilizes the colorimetric response of amine functionalized PDA vesicles to surfactin, a bacterial cyclic lipopeptide commonly released by Gram-positive Bacillus species as an antibiotic. To improve the sensitivity of PDA vesicles to surfactin by increasing the number and surface area of immobilized vesicles, the PDA vesicles were immobilized on the micropillar structure to give a hierarchical 3D PDA vesicle structure. For the fabrication of the 3D micropillar structure, polydimethylsiloxane (PDMS) was used to overcome the limitations imposed by silicon-based fabrication. In contrast to the 2D-PDA-PDMS system, which could only hardly detect the presence of 500 μM surfactin, the 3D-PDA-PDMS system could efficiently detect the presence of 5 μM surfactin and the initial presence of 4 × 101 cells/ml of Bacillus subtilis NCIB3610, which actively produces surfactin. Furthermore, bacterial strains that are known to produce no surfactin, such as Staphylococcus aureus Newman, Escherichia coli DH5α, and Pseudomonas aeruginosa PA14 were not detected by our system suggesting that the 3D-PDA-PDMS system is highly specific to surfactin but not to other chemicals produced by bacteria. Taken together, our results suggest that the 3D-PDA-PDMS system can sensitively and selectively be used for the high throughput detection and screening of biotechnologically important surfactin-producing bacterial strains

Cell Deformation by Single-beam Acoustic Trapping: A Promising Tool for Measurements of Cell Mechanics

We demonstrate a noncontact single-beam acoustic trapping method for the quantification of the mechanical properties of a single suspended cell with label-free. Experimentally results show that the single-beam acoustic trapping force results in morphological deformation of a trapped cell. While a cancer cell was trapped in an acoustic beam focus, the morphological changes of the immobilized cell were monitored using bright-field imaging. The cell deformability was then compared with that of a trapped polystyrene microbead as a function of the applied acoustic pressure for a better understanding of the relationship between the pressure and degree of cell deformation. Cell deformation was found to become more pronounced as higher pressure levels were applied. Furthermore, to determine if this acoustic trapping method can be exploited in quantifying the cell mechanics in a suspension and in a non-contact manner, the deformability levels of breast cancer cells with different degrees of invasiveness due to acoustic trapping were compared. It was found that highly-invasive breast cancer cells exhibited greater deformability than weakly-invasive breast cancer cells. These results clearly demonstrate that the single-beam acoustic trapping technique is a promising tool for non-contact quantitative assessments of the mechanical properties of single cells in suspensions with label-free.1