Contribution of hematopoietic stem cells in blood vessel formation

Vascular development consists of vasculogenesis and angiogenesis. The system of TIE2-Angiopoietin (Ang) is involved in angiogenesis. TIE2 regulates adhesion and dissociation between endothelial cells and mural cells, and survival, apoptosis, and chemotaxis of endothelial cells. Ang-2, which is produced by endothelial cells under tissue hypoxia, has been suggested to be a key regulator for the initiation of endothelial cell sprouting from pre-existing vessels. Although Ang-2 binds to TIE2, it does not promote activation of TIE2 on endothelial cells. Ang-2 produced from endothelial cells under hypoxia inhibits the binding of Ang-1 to TIE2. On the other hand, Ang-1 promotes activation of TIE2 and adhesion between endothelial cells and mural cells. Therefore, endothelial cells dissociated from mural cells by Ang-2 are free to move to avascular area where oxygen or nutrient is needed. We recently found that hematopoietic stem cells produce Ang-1 and promote chemotaxis and network formation of TIE2-positive endothelial cells. Moreover, hematopoietic stem cells change their fate into mural cell and stabilize the vessel structure. This novel function may be applied clinically to promote neovascularization by transplanting the hematopoietic stem cells at the desired site.Biomedical Reviews 2003; 14: 1-8

Stabilization of SF₅⁻ with Glyme-Coordinated Alkali Metal Cations

The stabilization of complex fluoroanions derived from weakly acidic parent fluorides is a significant and ongoing challenge. The [SF₅]⁻ anion is recognized as one such case, and only a limited number of [SF₅]⁻ salts are known to be stable at room temperature. In the present study, glyme-coordinated alkali metal cations (K⁺, Rb⁺, and Cs⁺) are employed to stabilize [SF₅]⁻, which provides a simple synthetic route to a [SF₅]⁻ salt. The reactivities of KF and RbF with SF₄ are significantly enhanced by complexation with G4, based on Raman spectroscopic analyses. A new room-temperature stable salt, [Cs(G4)₂][SF₅] (G4 = tetraglyme), was synthesized by stoichiometric reaction of CsF, G4, and SF₄. The vibrational frequencies of [SF₅]⁻ were assigned based on quantum chemical calculations, and the shift of the G4 breathing mode accompanying coordination to metal cations was confirmed by Raman spectroscopy. Single-crystal X-ray diffraction revealed that Cs⁺ is completely isolated from [SF₅]⁻ by two G4 ligands and [SF₅]⁻ is disordered along the crystallographic two-fold axis. Hirshfeld surface analysis reveals that the H···H interaction between two neighboring [Cs(G4)₂]⁺ moieties is more dominant on the Hirshfeld surface than the interaction between the H atom in glyme molecules and the F atom in [SF₅]⁻, providing a CsCl-type structural model where the large and spherical [Cs(G4)₂]⁺ cations contact each other and the [SF₅]⁻ anions occupy interstitial spaces in the crystal lattice. The [SF₅]⁻ anion, combined with [Cs(G4)₂]⁺, exhibits a very limited deoxofluorinating ability toward hydroxyl groups in both neat conditions and THF solutions

The Clinical Characteristics and Treatment Status of Psoriatic Arthritis

Psoriatic arthritis (PsA) is a complex musculoskeletal disorder. Its clinical features include psoriasis, peripheral arthritis, spinal involvement, enthesitis, and dactylitis. Typically, skin lesions precede osteoarticular lesions, although osteoarticular lesions can precede skin lesions in some cases. This study aimed to investigate the onset pattern of PsA, the time interval between the occurrence of skin and osteoarticular lesions, and the treatment status of PsA. A total of 64 patients with PsA who had been assessed according to the CASPAR criteria were enrolled. Of those, 75% had a typical lesion onset pattern where skin lesions preceded osteoarticular lesions (skin leading) and 16% had an osteoarticular leading lesion pattern. The mean time interval between the onset of lesions in patients with the skin leading pattern was 14.2 years and that in patients with the osteoarticular leading pattern was 4.5 years. Non-steroidal anti-inflammatory drugs were prescribed to 39% of patients, conventional synthetic disease modifying antirheumatic drugs (DMARDs) to 64%, and biologic DMARDs to 51.5%. In conclusion, there were several cases where osteoarticular lesions preceded skin lesions in PsA; therefore, care should be taken with regard to oligo- or poly-arthritis patients with a negative rheumatoid factor without the presence of skin lesions

Combinational Treatment of Trichostatin A and Vitamin C Improves the Efficiency of Cloning Mice by Somatic Cell Nuclear Transfer.

Somatic cell nuclear transfer (SCNT) provides a unique opportunity to directly produce a cloned animal from a donor cell, and it requires the use of skillful techniques. Additionally, the efficiencies of cloning have remained low since the successful production of cloned animals, especially mice. There have been many attempts to improve the cloning efficiency, and trichostatin A (TSA), a histone deacetylase inhibitor, has been widely used to enhance the efficiency of cloning. Here, we report a dramatically improved cloning method in mice. This somatic cell nuclear transfer method involves usage of Hemagglutinating virus of Japan Envelope (HVJ-E), which enables easy manipulation. Moreover, the treatment using two small molecules, TSA and vitamin C (VC), with deionized bovine serum albumin (dBSA), is highly effective for embryonic development. This approach requires neither additional injection nor genetic manipulation, and thus presents a simple, suitable method for practical use. This method could become a technically feasible approach for researchers to produce genetically modified animals from cultured cells. Furthermore, it might be a useful way for the rescue of endangered animals via cloning

Selective arterial embolization with gelatin particles for refractory knee hemarthrosis

PURPOSEWe aimed to evaluate the feasibility and safety of selective arterial embolization for refractory knee hemarthrosisMATERIALS AND METHODSTranscatheter arterial embolization for refractory knee hemarthrosis was performed on five female patients (median age, 77 years; range, 71–80 years) between May 2009 and September 2012. Selective arterial embolization of the feeding artery was performed using a 2.5 F microcatheter coaxially advanced from a 5 F catheter with its tip positioned in the superficial femoral artery. One- or two-millimeter gelatin particles were used as embolic agents.RESULTSIn all patients, transarterial embolization performed successfully after arteriography showed nontumorous staining around the knee joint. The feeding arteries were the lateral superior genicular artery in all five patients, the lateral inferior genicular artery in four patients, the medial superior genicular artery in one patient, the medial inferior genicular artery in one patient, the middle genicular artery in one patient, and the descending genicular artery in one patient. In all five patients, staining was remarkably diminished around the knee joint after the embolization procedure. No complication was observed. The hemarthrosis improved after the embolization, and the postoperative course has been uneventful with no recurrence in any patient.CONCLUSIONThese results suggest that selective arterial embolization for refractory hemarthrosis of the knee is safe and useful

Improvement of the target sensitivity in DECIGO by optimizing its parameters for quantum noise including the effect of diffraction loss

DECIGO is the future Japanese gravitational wave detector in outer space. We previously set the default design parameters to provide a good target sensitivity to detect the primordial gravitational waves (GWs). However, the updated upper limit of the primordial GWs by the Planck observations motivated us for further optimization of the target sensitivity. Previously, we had not considered optical diffraction loss due to the very long cavity length. In this paper, we optimize various DECIGO parameters by maximizing the signal-to-noise ratio (SNR), for the primordial GWs to quantum noise including the effects of diffraction loss. We evaluated the power spectrum density for one cluster in DECIGO utilizing the quantum noise of one differential Fabry-Perot interferometer. Then we calculated the SNR by correlating two clusters in the same position. We performed the optimization for two cases: the constant mirror-thickness case and the constant mirror-mass case. As a result, we obtained the SNR dependence on the mirror radius, which also determines various DECIGO parameters. This result is the first step toward optimizing the DECIGO design by considering the practical constraints on the mirror dimension and implementing other noise sources.Comment: 13 pages, 12 figure