Magnetic properties of the spin-1/2 XXZ model on the Shastry-Sutherland lattice: Effect of long-range interactions

We study magnetic properties of the $S=1/2$ Ising-like XXZ model on the Shastry-Sutherland lattices with long-range interactions, using the quantum Monte Carlo method. This model shows magnetization plateau phases at one-half and one-third of the saturation magnetization when additional couplings are considered. We investigate the finite temperature transition to one-half and one-third plateau phases. The obtained results suggest that the former case is of the first order and the latter case is of the second order. We also find that the system undergoes two successive transitions with the 2D Ising model universality, although there is a single phase transition in the Ising limit case. Finally, we estimate the coupling ratio to explain the magnetization process observed in ${\rm TmB_4}$Comment: 5 pages, 6 figure

Percutaneous screw fixation without bone graft for cystic-type scaphoid fractures

金沢医療センター整形外科金沢大学医薬保健研究域医学系BACKGROUND:: The most controversial problem in treating scaphoid fractures is whether bone grafts are necessary for cystic-type fractures. METHODS:: We treated 105 scaphoid fractures using Herbert screws (1988-1997), AO 3.0 mm cannulated screws (1998-2002), and Acutrak screws (2003-2006). The patients ranged in age from 14 years to 67 years (average, 26 years). Our classifications were based on the radiographic findings: linear type (51 cases); cystic type (24 cases); and sclerotic or displaced type (30 cases). Linear and cystic types did not have any displacement more than 2 mm. If the fracture line had a sclerotic zone thicker than 1 mm, it was classified as sclerotic or displaced. The length of time before surgery did not affect the classification. Osteosynthesis was performed-without bone graft in all linear cases, with a bone graft in 7 and without a bone graft in 17 cases in cystic type, and with all bone graft in sclerotic or displaced type. RESULTS:: Bone union was achieved in all cases in linear type. There were one failure (AO) in 7 cases with bone graft and 3 failures (1 Herbert and 2 AO) in 17 cases without bone graft in cystic type. All 10 cases achieved bone union without bone graft in cystic type using Acutrak screw. There were two failure cases (2 AO) in sclerotic or displaced type. CONCLUSIONS:: Screw fixation without bone graft using Acutrak screws was a reliable strategy for the treatment of cystic-type scaphoid fractures. © 2008 by Lippincott Williams & Wilkins

Regulation of Adrenal Aldosterone Production by Serine Protease Prostasin

A serine protease prostasin has been demonstrated to have a pivotal role in the activation of the epithelial sodium channel. Systemic administration of adenovirus carrying human prostasin gene in rats resulted in an increase in plasma prostasin and aldosterone levels. However, the mechanism by which the elevation of prostasin levels in the systemic circulation stimulated the plasma aldosterone levels remains unknown. Therefore, we examined if prostasin increases the aldosterone synthesis in a human adrenocortical cell line (H295R cells). Luciferase assay using CYP11B2 promoter revealed that prostasin significantly increased the transcriptional activity of CYP11B2. Prostasin significantly increased both CYP11B2 mRNA expression and aldosterone production in a dose-dependent manner. Surprisingly, treatment with camostat mesilate, a potent prostasin inhibitor, had no effect on the aldosterone synthesis by prostasin and also a protease-dead mutant of prostasin significantly stimulated the aldosterone production. A T-type/L-type calcium channel blocker and a protein kinase C (PKC) inhibitor significantly reduced the aldosterone synthesis by prostasin. Our findings suggest a stimulatory effect of prostasin on the aldosterone synthesis by adrenal gland through the nonproteolytic action and indicate a new role of prostasin in the systemic circulation

A GO intervention program for enhancing elementary school children's cognitive functions and control abilities of emotion and behavior: study protocol for a randomized controlled trial

BACKGROUND: Executive function is critical for children's healthy development. We propose an intervention program to enhance children's executive function using the game, GO. Many neuroimaging studies have revealed that playing GO is related to executive function. In addition, previous studies also revealed that executive function can be enhanced by training. We will perform a randomized controlled trial to investigate the effectiveness of a GO intervention group and a control group without intervention. METHODS/DESIGN: 35 elementary school children aged 8 to 10 were recruited from Edogawa elementary school in Tokyo, Japan. They will be randomized into two groups; either the 5-week GO intervention group or no-intervention control group. We will ask the participants of the intervention group to join the GO course which will be held once every week for five weeks (total: six times). In the GO course, the children will be taught GO by the GO masters of the Nihon Ki-in and enjoy it for an hour. Besides the course, the participants will perform GO problems about twenty minutes a day, three times a week during the intervention period. We will use the Stroop task, the digit span, the Raven's colored progressive matrices, the Span-board task, and the Behavioral inhibition/behavioral activation scale for the outcome measures. Outcomes will be measured at a baseline (Assessment 1) and 5 weeks after the intervention program started (Assessment 2). The intervention group will be compared with the control group using one-way analyses of covariance with the difference between Assessment 1 and Assessment 2 measures as dependent variables and pretest scores as covariates. DISCUSSION: To our knowledge, this study will be the first RCT to investigate the efficacy of a GO intervention program for elementary school children. If this intervention is effective, we will be able to take the next steps in making an educational program to enhance children's executive function and other cognitive abilities using GO. In addition, we further will investigate the transfer effects of the GO intervention program through executive function. We also will investigate neuroplasticity with the GO intervention using neuroimaging. TRIAL REGISTRATION: UMIN Clinical Trials Registry UMIN00000632

Surgery for Irradiation Damage to the Digestive Tract.

The surgical outcome of radiation injury to the gut was evaluated on the basis of clinical experience. The main affected gut was the rectum in frequency. In most cases, colostomy was selected and the affected gut was left as it was. Some suffered from bleeding episode and 4 had carcinoma arising from radiation injury. In conclusion, early resection of affected guts associated with clinical symptoms is recommended as the treatment of radiation-injured gut

Inhibition of constitutively active Jak-Stat pathway suppresses cell growth of human T-cell leukemia virus type 1-infected T-cell lines and primary adult T-cell leukemia cells

BACKGROUND: Human T-cell leukemia virus type 1 (HTLV-1), the etiologic agent for adult T-cell leukemia (ATL), induces cytokine-independent proliferation of T-cells, associated with the acquisition of constitutive activation of Janus kinases (Jak) and signal transducers and activators of transcription (Stat) proteins. Our purposes in this study were to determine whether activation of Jak-Stat pathway is responsible for the proliferation and survival of ATL cells, and to explore mechanisms by which inhibition of Jak-Stat pathway kills ATL cells. RESULTS: Constitutive activation of Stat3 and Stat5 was observed in HTLV-1-infected T-cell lines and primary ATL cells, but not in HTLV-1-negative T-cell lines. Using AG490, a Jak-specific inhibitor, we demonstrated that the activation of Stat3 and Stat5 was mediated by the constitutive phosphorylation of Jak proteins. AG490 inhibited the growth of HTLV-1-infected T-cell lines and primary ATL cells by inducing G(1 )cell-cycle arrest mediated by altering the expression of cyclin D2, Cdk4, p53, p21, Pim-1 and c-Myc, and by apoptosis mediated by the reduced expression of c-IAP2, XIAP, survivin and Bcl-2. Importantly, AG490 did not inhibit the growth of normal peripheral blood mononuclear cells. CONCLUSION: Our results indicate that activation of Jak-Stat pathway is responsible for the proliferation and survival of ATL cells. Inhibition of this pathway may provide a new approach for the treatment of ATL