Extrathymic differentiation of resident T cells in the joints of mice with collagen-induced arthritis

Murine collagen-induced arthritis (CIA) is known as a T cell-mediated autoimmune disease, although autoantibodies are also suspected to be associated with the onset of the disease. To determine the origin of such T cells in the joints of mice with CIA, their phenotypic properties as well as those of T cells in other immune organs were examined in DBA/1 mice. Since a significant number of mononuclear cells (MNC) was also yielded by the joints of normal DBA/1 mice, the properties of these T cells were examined in parallel. When CIA was induced by an intradermal injection of type II collagen at the base of the tail, the numbers of MNC yielded by the regional lymph nodes and the foot joints were doubled. Interestingly, regardless of the onset of CIA, the joints were always comprised of unique T cell populations, including IL-2(R)alpha- beta+ T cells, gammadelta T cells, CD8alpha+ beta- cells, and CD44+ L-selectin- cells. All these properties coincide with those of extrathymic T cells in liver and intestine. In the case of gammadelta T cells in joints, Vgamma and Vdelta usages were unique and different from those in the other organs. More importantly, Vgamma and Vdelta usages in gammadelta T cells in the joints of normal mice and in those of mice with CIA were essentially the same. Taken together with the expression of recombination-activating gene-1 and -2 mRNAs by MNC in mice with CIA, these findings raise the possibility that the joints have their own resident T cells that are extrathymically generated in situ.     

Fundamental characteristics of printed gelatin utilizing micro 3D printer

Gelatin is useful for biofabrication, because it can be used for cell scaffolds and it has unique properties. Therefore, we attempted to fabricate biodevices of gelatin utilizing micro 3D printer which is able to print with high precision. However, it has been difficult to fabricate 3D structure of gelatin utilizing 3D printer, because a printed gelatin droplet on the metal plate electrode would spread before solidification. To clear this problem, we developed a new experimental set-up with a peltier device that can control temperature of the impact point. At an impact point temperature of 80 °C, the spreading of printed gelatin droplets was prevented. Therefore, we were able to print a ball gelatin. In addition, we were able to print a narrower gelatin line than at an impact point temperature of 20 °C.     

Fabrication of micro-gelatin fiber utilizing coacervation method

Biotechnology has drastically been advanced by the development of iPS and ES cells, which are representative forms induced pluripotent stem cells. In the micro/nano bio field, the development of cells and Taylor-made medicine for a potential treatment of incurable diseases has been a center of attention. The melting point of gelatin is between 25 and 33 °C, and the sol–gel transition occurs in low temperature. This makes the deformation of this useful biomaterial easy. The examples of gelatin fiber applications are suture threads, blood vessel prosthesis, cell-growth-based materials, filter materials, and many others. Because the cell size differs depending on the species and applications, it is essential to fabricate gelatin fibers of different diameters. In this paper, we have developed a fabrication method for gelatin fibers the coacervation method. We fabricated narrow gelatin fibers having a diameter over 10 μm.     

In vitro calcification of UHMWPE/PU composite membrane

Polyurethane composite made from biaxially drawn ultrahigh molecular weight polyethylene (BDUHMWPE) is likely an alternative for polyurethane currently being plagued for medical applications. In this study, an in vitro calcification protocol was used to determine the relative resistance to calcification of the composite membranes. The results demonstrated that the composite membranes were susceptible to extrinsic calcification that was closely related to the matrix polyurethane material used. The calcification of the composite was different from that of the solution cast polyurethane membranes. The incorporation of hydrophobic reinforcement BDUHMWPE effectively postponed the calcification. The differences of calcification between composite and polyurethane were greatly due to the differences in surface structures and properties of the as-cast polyurethane.     

Pipe Jacking Method for Long Curve Construction

The D301 pipe jacking method is the first to accomplish long spans, curves and high speed construction in the field of small diameter (300 mm) tunneling. The design of the system components are described: tunneling machine with directional control ability, jacking machine, power unit, and control unit which contains a microprocessor. As a result of field tests in about 100 m in length with a 200 curvature radius, the following capabilities are confirmed: the span length is up to 100 m, the curvature radius is down to 200 m, it is useable in either cohesive or sandy soils having N‐curves up to 10, and the construction speed is up to 3 m∕h.     

Titanium nitride film as a protective coating for a vacuum deposition chamber

A hard and anti-corrosive titanium nitride coating is proposed for use as a permanent coating layer on the inside walls of vacuum chambers and tooling that are exposed to repeated depositions of soft metals. Excellent characteristics for the removal of deposited aluminum or copper by either chemical cleaning or glass bead blasting are demonstrated. The completion of removal can easily be monitored by the obvious gold color of the coating layer.The outgassing rate at room temperature is considerably lower than that of bare stainless steel plate. Characterization of the titanium nitride layer is made by X-ray diffraction, Auger electron spectroscopy, electron spectroscopy for chemical analysis, and secondary ion mass spectrometry.     

Uretero-external iliac artery fistula: a case report

We report a case of uretero-external iliac artery fistula. A 60-year-old female was referred to our hospital complaining of intermittent gross macrohematuria. She had undergone radical hysterectomy, radiation therapy and chemotherapy for advanced cervical cancer 2 years ago. The patient had a 7 Fr ureteral double-J stent for left hydronephrosis. Retrograde urography showed a filling defect (8 mm in diameter) of the left ureter. A contrast-enhanced computed tomographic scan showed left hydronephrosis and hydroureter but no evidence of fistula formation or extravasation. A pelvic arteriography revealed a pseudoaneurysm of the left external iliac artery at the crosspoint between the left ureter and the iliac artery. Surgical repair of the left uretero-external arterial fistula was successfully performed as well as left nephroureterectomy. The possibility of fistula formation between ureter and artery should be kept in mind in patients with long-term indwelling ureteral stents and history of radiation therapy.     

Durable Ultraflexible Organic Photovoltaics with Novel Metal‐Oxide‐Free Cathode

Flexible and stretchable organic photovoltaics (OPVs) are promising as a power source for wearable devices with multifunctions ranging from sensing to locomotion. Achieving mechanical robustness and high power conversion efficiency for ultraflexible OPVs is essential for their successful application. However, it is challenging to simultaneously achieve these features by the difficulty to maintain stable performance under a microscale bending radius. Ultraflexible OPVs are proposed by employing a novel metal‐oxide‐free cathode that consists of a printed ultrathin metallic transparent electrode and an organic electron transport layer to achieve high electron‐collecting capabilities and mechanical robustness. In fact, the proposed ultraflexible OPV achieves a power conversion efficiency of 9.7% and durability with 74% efficiency retention after 500 cycles of deformation at 37% compression through buckling. The proposed approach can be applied to active layers with different morphologies, thus suggesting its universality and potential for high‐performance ultraflexible OPV devices.