Transmission of hepatitis B virus from hepatitis B core antibody-positive donors in living related liver transplants

A factor fundamental to bone formation has been identified. Gene targeting shows that core-binding factor alpha 1 (Cbfa1) plays an essential role in bone formation and osteoblast differentiation. Thus, it is now possible to begin examining the molecular mechanism of bone formation--especially osteoblast differentiation.     

A laser-recrystallization technique for silicon-TFT integratedcircuits on quartz substrates and its application to small-sizemonolithic active-matrix LCD's

The laser-recrystallization technique utilizes the connected-island structure for forming recrystallized silicon films with enlarged grain size controlled by the thermal gradient. This technique has been used to fabricate the driver circuits of small-size monolithic active-matrix liquid-crystal displays. A horizontal driver circuit with partially recrystallized silicon thin-film transistors (TFTs) has been successfully fabricated on quartz substrates, together with a vertical driver and active-matrix TFT circuits. The operating frequency of the fabricated horizontal driver circuits can be as high as 10 MHz under a clock voltage of 5 V     

AlGaN/GaN power HFET on silicon substrate with source-via grounding (SVG) structure

We have developed a high-power AlGaN/GaN HFET fabricated on 4-in conductive Si substrate with a source-via grounding (SVG) structure. The SVG structure enables efficient chip layout and high packing density by the vertical configuration. By establishing a high-quality epitaxial technology on a Si substrate and by significantly reducing the parasitic resistance, a very low specific on-state resistance of 1.9 m/spl Omega//spl middot/cm/sup 2/ is achieved. The breakdown voltage is as high as 350 V, which is attributed to the Si substrate acting as a backside field plate. Because of reduction of the parasitic inductance, very high level of current (2.0 kA/cm/sup 2/) transients, i.e., a turn-on time of 98 ps and a turn-off time of 96 ps, are successfully measured for the first time.     

Hepatic artery thrombosis in living related liver transplantation

BACKGROUND: Hepatic artery thrombosis (HAT) after orthotopic liver transplantation remains a significant cause of graft loss in pediatric patients. We previously reported that the microsurgical techniques for arterial anastomosis can reduce the incidence of HAT in living related liver transplantation (LRLT). The purpose of this study is to analyze the risk factors for HAT after LRLT. A total of 245 patients received 250 liver transplants. METHODS: Eight arteries in eight patients, reconstructed with the use of loupe magnification (HAT; 1/8, 12.5%), were excluded from this study. We observed HAT in 4 patients of the 242 transplants (1.7%, HAT group). Seventeen factors were compared between the HAT and the control group (those without HAT). RESULTS: HAT occurred in 3 of 33 grafts (9%) from ABO-incompatible donors, whereas it occurred in 1 of 209 grafts (0.5%) from identical or compatible donors (P=0.008). The corrected volume of fresh-frozen plasma intraoperatively transfused in the HAT group (46.9+/-30.3 ml/kg) was significantly (P=0.015) different from that in the control group (10.2+/-1.9 ml/mg). In all four patients with HAT, emergent revisions of the anastomosis were performed. Two patients with ABO-incompatible grafts died of hepatic failure and sepsis. CONCLUSIONS: Although microsurgical techniques can minimize the surgical risk factors for HAT, overtransfusion of fresh-frozen plasma in high-risk patients (ABO incompatible) may be a critical factor in the development of HAT in LRLT.     

Source resistance reduction of AlGaN-GaN HFETs with novel superlattice cap layer

We have developed a novel AlGaN-GaN heterojunction field effect transistor (HFET) with an ultralow source resistance by employing the novel superlattice (SL) cap structure. The particular advantage of the SL cap, i.e., the existence of multiple layers of the polarization-induced two-dimensional electron gas (2DEG) with high mobility and high concentration at each AlGaN-GaN interface, is fully exploited for lowering the lateral resistance and the potential barrier at the interface of the SL cap and the HFET barrier layer. By designing the AlGaN-GaN thickness ratio, we have established a method to obtain the optimized SL structure and have achieved an extremely low source resistance of 0.4 /spl Omega//spl middot/mm which is lower not only than HFETs with the conventional structure but also than those with the n-GaN cap structure. The SL cap HFET fabricated on a sapphire substrate exhibited excellent dc and RF performance, i.e., maximum transconductance of over 400 mS/mm, maximum drain current of 1.2 A/mm, a cutoff frequency of 60 GHz, a maximum frequency of oscillation of 140 GHz, and a very low noise figure minimum of 0.7 dB at 12 GHz.     

Coexistence of a graft with the preserved native liver in auxiliary partial orthotopic liver transplantation from a living donor for ornithine transcarbamylase deficiency

BACKGROUND: Auxiliary partial orthotopic liver transplantation (APOLT) has recently been performed in patients with noncirrhotic metabolic liver diseases. However, long-term outcomes for the preserved native liver and the transplanted liver graft have not been clearly established yet. METHODS: The recipient was a 36-month-old girl with ornithine transcarbamylase deficiency. She underwent APOLT, using her father's left lateral segment. RESULTS: Liver function was normalized soon after APOLT and the patient was able to ingest a normal diet without medication. Coexistence of the well-functioning native liver and graft was demonstrated in a computed tomography scan, Doppler ultrasonography, scintigraphy, and histological examination, during a relatively long-term follow-up period. CONCLUSIONS: APOLT seems to be most useful for the treatment of noncirrhotic metabolic liver diseases.     

Living-related liver transplantation and neurological outcome in children with fulminant hepatic failure

In vivo, endothelial cells (ECs) are subjected to a complex mechanical environment composed of shear stress, pressure, and circumferential stretch. The aim of this study was to subject bovine aortic ECs to a pulsatile pressure oscillating from 70 to 130 mm Hg (mean of 100 mm Hg) in combination with pulsatile shear stresses from 0.1 to 6 dyne/cm2 (1 dyne/cm2=0.1 N/m2) with or without a cyclic circumferential stretch of 4% for 1, 4, and 24 hours. The effect of highly reversing oscillatory shear stress (range -3 to +3 dyne/cm2, mean of 0.3 dyne/cm2) typical of regions prone to the development of atherosclerotic plaques was also studied at 4 and 24 hours. Endothelin-1 (ET-1) and endothelial constitutive nitric oxide synthase (ecNOS) mRNA expression was time and mechanical force dependent. ET-1 mRNA was maximal at 4 hours and decreased to less than static culture expression at 24 hours, whereas ecNOS mRNA increased over time. Pressure combined with low shear stress upregulated ET-1 and ecNOS mRNA compared with static control. Additional increase in expression for both genes was observed under a combination of higher shear stress and pressure. A cyclic circumferential stretch of 4% did not induce a further increase in ET-1 and ecNOS mRNA at either low or high shear stress. Oscillatory shear stress with pressure induced a higher expression of ET-1 mRNA but lower expression of ecNOS mRNA compared with unidirectional shear stress and pressure. We have shown that the combination of pressure and oscillatory shear stress can downregulate ecNOS levels, as well as upregulate transient expression of ET-1, compared with unidirectional shear stress. These results provide a new insight into the exact role of mechanical forces in endothelial dysfunction in regions prone to the development of atherosclerosis.     

Evaluation of risk and benefit in thermal effusivity sensor for monitoring lubrication process in pharmaceutical product manufacturing

In the process design of tablet manufacturing, understanding and control of the lubrication process is important from various viewpoints. A detailed analysis of thermal effusivity data in the lubrication process was conducted in this study. In addition, we evaluated the risk and benefit in the lubrication process by a detailed investigation. It was found that monitoring of thermal effusivity detected mainly the physical change of bulk density, which was changed by dispersal of the lubricant and the coating powder particle by the lubricant. The monitoring of thermal effusivity was almost the monitoring of bulk density, thermal effusivity could have a high correlation with tablet hardness. Moreover, as thermal effusivity sensor could detect not only the change of the conventional bulk density but also the fractional change of thermal conductivity and thermal capacity, two-phase progress of lubrication process could be revealed. However, each contribution of density, thermal conductivity, or heat capacity to thermal effusivity has the risk of fluctuation by formulation. After carefully considering the change factor with the risk to be changed by formulation, thermal effusivity sensor can be a useful tool for monitoring as process analytical technology, estimating tablet hardness and investigating the detailed mechanism of the lubrication process.