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A three-dimensional (3D) topological insulator features a 2D surface state consisting of a single linearly dispersive Dirac cone1–3. Under broken time-reversal symmetry, the single Dirac cone is predicted to cause half-integer quantization of Hall conductance, which is a manifestation of the parity anomaly in quantum field theory1–9. However, despite various observations of quantization phenomena10–15, the half-integer quantization has not been observed because most experiments simultaneously measure a pair of equivalent Dirac cones16on two opposing surfaces. Here we demonstrate the half-integer quantization of Hall conductance in a synthetic heterostructure termed a semi-magnetic topological insulator, where only one surface state is gapped by magnetic doping and the opposite one is non-magnetic and gapless. We observe half-quantized Faraday and Kerr rotations with terahertz magneto-optical spectroscopy and half-quantized Hall conductance in transport at zero magnetic field. Our results suggest a condensed-matter realization of the parity anomaly4–9and open a way for studying the physics enabled by a single Dirac fermion.

Cell formation (CF) is a vital aspect of the design of cellular manufacturing systems. Many similarity coefficient method (SCM)-based approaches have been proposed to solve the CF problem in the literature. However, some of these approaches have deficiencies and do not always produce proper machine groups and part families from the initial machine-part incidence matrix. This paper considers a new systematic approach that is based upon the calculation of an average voids value (AVV), which indicates the average number of newly produced voids when a pair of machine groups are combined. This approach is very simple, intuitively appealing, and overcomes many disadvantages inherent in some traditional SCM-based approaches. The AVV approach is tested against five well-known approaches in solving CF problems and the test results show that the approach is reliable and efficient. [C] 2001 Elsevier Science Ltd. All rights reserved. Keywords: Group technology; Cellular manufacturing systems; Similarity and dissimilarity coefficients

Tissue decellularization produces a three‐dimensional scaffold that can be used to fabricate functional liver grafts following recellularization. Inappropriate cell distribution and clotting during blood perfusion hinder the practical use of recellularized livers. Here we aimed to establish a seeding method for the optimal distribution of parenchymal and endothelial cells, and to evaluate the effect of liver sinusoidal endothelial cells (LSECs) in the decellularized liver. Primary rat hepatocytes and LSECs were seeded into decellularized whole‐liver scaffolds via the biliary duct and portal vein, respectively. Biliary duct seeding provided appropriate hepatocyte distribution into the parenchymal space, and portal vein–seeded LSECs simultaneously lined the portal lumen, thereby maintaining function and morphology. Hepatocytes co‐seeded with LSECs retained their function compared with those seeded alone. Platelet deposition was significantly decreased and hepatocyte viability was maintained in the co‐seeded group after extracorporeal blood perfusion. In conclusion, our seeding method provided optimal cell distribution into the parenchyma and vasculature according to the three‐dimensional structure of the decellularized liver. LSECs maintained hepatic function, and supported hepatocyte viability under blood perfusion in the engineered liver graft owing to their antithrombogenicity. This recellularization procedure could help produce practical liver grafts with blood perfusion. The authors provide a seeding method for achieving optimal cell distribution in the parenchyma and vasculature of the decellularized liver, and evaluate the effect of endothelial cells in the engineered liver.

Myositis is rarely associated with Behcet's disease. We report such a case with characteristic magnetic resonance imaging (MRI) findings, and review the literature. CASE REPORT A 29 year old man [...]

For many producers, introduction of improved animal welfare systems is a turning point in their future production strategies as it increases production costs. The increase in egg retail prices is of growing concern not only for producers, but also for retailers and consumers. However, no report has calculated the estimated production costs or retail prices associated with introducing practices that support improved animal welfare in poultry farms in Japan. Therefore, this study aimed to estimate the production costs and table egg prices of 6 types of laying hen systems: conventional cage (CC): 8- and 12-tiers (CC8, CC12), enriched cage (EC): 8- and 12-tiers (EC8, EC12), aviary (AV), and barn systems (BR). Production costs include land purchases, construction costs of facilities, equipment and machinery, quantity of feed provided, farming materials invested, and wages.

Geometry, both in momentum and in real space, plays an important role in the electronic dynamics of condensed matter systems. Among them, the Berry phase associated with nontrivial geometry can be an origin of the transverse motion of electrons, giving rise to various geometric effects such as the anomalous, spin and topological Hall effects. Here, we report two unconventional manifestations of Hall physics: a sign-reversal of the anomalous Hall effect, and the emergence of a topological Hall effect in magnetic/non-magnetic topological insulator heterostructures, Crx(Bi1−ySby)2−xTe3/(Bi1−ySby)2Te3. The sign-reversal in the anomalous Hall effect is driven by a Rashba splitting at the bulk bands, which is caused by the broken spatial inversion symmetry. Instead, the topological Hall effect arises in a wide temperature range below the Curie temperature, in a region where the magnetic-field dependence of the Hall resistance largely deviates from the magnetization. Its origin is assigned to the formation of a Néel-type skyrmion induced by the Dzyaloshinskii–Moriya interaction.

Dual phase 980 MPa grade (DP980) steel sheets were resistance spot welded using a pulsed current, and the effects of the pulsed current on the strength properties of the joints were investigated. The pulsed current improved the mechanical properties of the joints in cross tensile tests. In situobservations during tear tests revealed that the ductility of the nugget was improved and that the propagation of cracks into the nugget was inhibited when the pulsed current was used. Microstructural observations and electron probe microanalysis (EPMA) of the nugget showed that the segregation of phosphorus at the nugget was reduced in the joint welded using the pulsed current, suggesting that the pulsed current improved the ductility of the nugget by altering their microstructures.

In order to better understand the microstructural evolution in steel welds, in-situexperiments using time-resolved X-ray diffraction (TRXRD) and laser scanning confocal microscopy (LSCM) are performed and the phase transformations that occur during welding of C–Mn–Al steels are directly observed. Ferrite and austenite phases are identified and quantified in the fusion zone (FZ) using the real time TRXRD and LSCM data. The results show non-equilibrium peritectic transition during rapid cooling, in contrast to the equilibrium d-ferrite solidification that occurs under slow cooling conditions. Austenite nucleates along d-ferrite grain boundaries during the d??transformation, whereas during the ??atransformation, the microstructures change from Widmanstatten ferrite (WF) to intragranular bainitic ferrite in the rapidly and slowly cooled welds, respectively. Using these real time observations, important kinetic information about phase transformations during steel weld solidification can be determined.

The microstructures at the cladded interface between two low alloy steels, a mild steel and HT780, having different transformation temperatures, were characterised using optical microscopy, SEM and nanoindentation. To study the effects of heat on the near interface structures, the HT780 clad steel plate was welded and heat treated. It was found that cladding produced an interfacial layer with greater hardness than was found in either steel type tested and that carbon was enriched in this layer. During welding, the interfacial layer broadened and its hardness increased in the heat affected zone, which was heated to approximately the transformation temperature, but then softened again at temperatures above Ac3. Hardening of the interfacial layer occurred under various cooling rates. These microstructural changes are potentially due to the difference between the transformation temperatures of mild steel and HT780.

The sequential separation technique of U, Th, Pb, and the lanthanides with a single anion-exchange column was applied to analysis of the geochemical reference sample, JB-1. The separation technique was previously developed by the authors and reported. The sample was digested and dissolved in nitric acid. Five solutions of different volume containing 0.1–1 mg of the JB-1 were loaded on the separate columns, and the elements of interest in the solution were sequentially separated. The concentrations of the elements were measured with an ICP-MS. The elements were successfully separated and alkaline metals and alkaline earth metals were effectively eliminated from the elements. The elemental concentrations were concordant with the literature values within the deviation except for that of Th. The elemental concentrations were accurately determined in ≥500 μg of the JB-1 without subtraction of processing blanks.

Introduction: Safe peritoneal access and gastric closure are the most important concerns in clinical applications of NOTES. Our past study demonstrated usefulness of the submucosal tunnel technique for safe peritoneal access and closure with endoclips. However, such closure is sometimes difficult and time‐consuming. This study investigated the feasibility of fibrin glue for submucosal tunnel closure in a NOTES porcine model.

We present a summary of our work towards developing spectroscopic and nuclear imaging detectors using epitaxially grown thick single crystal CdTe layers on Si substrates. High crystalline quality thick single crystal CdTe layers (>260 m) were obtained where the growth rates could be varied from 10-70 m/h by adjusting the precursor's flow rates, ratios and the substrate temperatures. Both high resistivity p-like CdTe layers and highly conductive n+-CdTe layers with controlled electrical properties were obtained using iodine as a dopant, but using different growth conditions. Detectors were fabricated in a p-CdTe/n+-CdTe/n+-Si heterojunction diode structure, which demonstrated their energy discrimination capability by resolving energy peaks from a gamma source. Details on the growth characteristics and the fabrication process for a 2-D imaging array are presented.

Introduction: Indications for laparoscopic surgery for colonic diverticular disease have not been established in Japan despite this being a relatively common disease. We studied surgical outcomes of laparoscopic colon resection (LCR) versus open colon resection (OCR) for diverticular disease.

Intrinsic stem cells (SC) participate in tissue remodeling and regeneration in various diseases and following toxic insults. Failure of tissue regeneration is in part attributed to lack of SC protection from toxic stress of noxious stimuli, thus prompting intense research efforts to develop strategies for SC protection and functional preservation for in vivo delivery. One strategy is creation of artificial SC niches in an attempt to mimic the requirements of endogenous SC niches by generating scaffolds with properties of extracellular matrix. Here, we investigated the use of hyaluronic acid (HA) hydrogels as an artificial SC niche and examined regenerative capabilities of encapsulated embryonic endothelial progenitor cells (eEPC) in three different in vivo models. Hydrogel-encapsulated eEPC demonstrated improved resistance to toxic insult (adriamycin) in vitro, thus prompting in vivo studies. Implantation of HA hydrogels containing eEPC to mice with adriamycin nephropathy or renal ischemia resulted in eEPC mobilization to injured kidneys (and to a lesser extent to the spleen) and improvement of renal function, which was equal or superior to adoptively transferred EPC by intravenous infusion. In mice with hindlimb ischemia, EPC encapsulated in HA hydrogels dramatically accelerated the recovery of collateral circulation with the efficacy superior to intravenous infusion of EPC. In conclusion, HA hydrogels protect eEPC against adriamycin cytotoxicity and implantation of eEPC encapsulated in HA hydrogels supports renal regeneration in ischemic and cytotoxic (adriamycin) nephropathy and neovascularization of ischemic hindlimb, thus establishing their functional competence and superior capabilities to deliver stem cells stored in and released from this bioartificial niche.

Unilateral ureteral obstruction (UUO), a model of tubulointerstitial scarring (TIS), has a propensity toward regeneration of renal parenchyma after release of obstruction (RUUO). No information exists on the contribution of stem cells to this process. We performed UUO in FVB/N mice, reversed it after 10 days, and examined kidneys 3 wk after RUUO. UUO resulted in attenuation of renal parenchyma. FACS analysis of endothelial progenitor (EPC), mesenchymal stem (MSC) and hematopoietic stem (HSC) cells obtained from UUO kidneys by collagenase-dispersed single-cell suspension showed significant increase in EPC, MSC, and HSC compared with control. After RUUO cortical parenchyma was nearly restored, and TIS score improved by 3 wk. This reversal process was associated with return of stem cells toward baseline level. When animals were chronically treated with nitric oxide synthase (NOS) inhibitor at a dose that did not induce hypertension but resulted in endothelial dysfunction, TIS scores were not different from control UUO, but EPC number in the kidney decreased significantly; however, parenchymal regeneration in these mice was similar to control. Blockade of CXCR4-mediated engraftment resulted in dramatic worsening of UUO and RUUO. Similar results were obtained in caveolin-1-deficient but not -overexpressing mice, reflecting the fact that activation of CXCR4 occurs in caveolae. The present data show increase in EPC, HSC, and MSC population during UUO and a tendency for these cells to decrease to control level during RUUO. These processes are minimally affected by chronic NOS inhibition. Blockade of CXCR4-stromal cell-derived factor-1 (SDF-1) interaction by AMD3100 or caveolin-1 deficiency significantly reduced the UUO-associated surge in stem cells and prevented parenchymal regeneration after RUUO. We conclude that the surge in stem cell accumulation during UUO is a prerequisite for regeneration of renal parenchyma.

AbstractAnion-exchange chromatography of element 105, dubnium (Db), produced in the 248Cm( 19F, 5n) 262Db reaction is investigated together with the homologues Nb and Ta, and the pseudo-homologue Pa in 13.9 M hydrofluoric acid (HF) solution. The distribution coefficient (Kd) of Db on an anion-exchange resin is successfully determined by running cycles of 1702 chromatographic column separations. The result clearly indicates that the adsorption of Db on the resin is significantly different from that of the homologues and that the adsorption of anionic fluoro complexes of these elements decreases in the sequence of Ta≈ Nb>Db≥Pa.

We report the effects of local administration of osteogenic protein-1 on the biomechanical properties of the overstretched anterior cruciate ligament in an animal model. An injury in the anterior cruciate ligament was created in 45 rabbits. They were divided into three equal groups. In group 1, no treatment was applied, in group II, phosphate-buffered saline was applied around the injured ligament, and in group III, 12.5 µg of osteogenic protein-1 mixed with phosphate-buffered saline was applied around the injured ligament. A control group of 15 rabbits was assembled from randomly-selected injured knees from among the first three groups. Each rabbit was killed at 12 weeks.The maximum load and stiffness of the anterior cruciate ligament was found to be significantly greater in group III than either group 1 (p = 0.002, p = 0.014) or group II (p = 0.032, p = 0.025). The tensile strength and the tangent modulus of fascicles from the ligament were also significantly greater in group III than either group I (p = 0.002, p = 0.0174) or II (p = 0.005, p = 0.022).The application of osteogenic protein-1 enhanced the healing in the injured anterior cruciate ligament, but compared with the control group the treated ligament remained lengthened. The administration of osteogenic protein-1 may have a therapeutic role in treating the overstretched anterior cruciate ligament.

Abstract: Background: Laparoscopy-assisted distal gastrectomy (LAG) is gaining acceptance for treating early gastric cancer. However, the long-term quality of life after LAG for gastric cancer is unknown. This study compared the long-term quality of life after LAG versus open distal gastrectomy (ODG) for early gastric cancer. Method: This study included 53 patients who underwent LAG and 37 patients who underwent ODG for treatment of early gastric cancer. Quality of life was evaluated on the basis of a 22-item questionnaire that addressed food tolerance and mental and physical conditions, scored on a scale of 1–3. Results: The mean follow-up periods after LAG and ODG were 99.3 and 97.0 months, respectively. Although the majority of patients who had undergone LAG were consuming a normal diet and had weight loss of less than 5 kg, all 22 items and the total score of the LAG group were comparable to those of the ODG group. However, the incidence of postoperative intestinal obstruction was significantly lower in the LAG group than in the ODG group (1% vs. 13%, p < 0.05). Conclusions: LAG is equivalent to ODG with respect to long-term quality of life and is associated with a reduced incidence of postoperative intestinal obstruction.

In order to clarify the role of cytokines in the remodelling of the grafted tendon for ligament reconstruction we compared the responses to interleukin (IL)-1ß, platelet-derived growth factor (PDGF)-BB and transforming growth factor (TGF)-ß1 of extrinsic fibroblasts infiltrating the frozen-thawed patellar tendon in rats with that of the normal tendon fibroblasts, in regard to the gene expression of matrix metalloproteinase (MMP)-13, using Northern blot analysis. We also examined, immunohistologically, the local expression of IL-1ß, PDGF-BB, and TGF-ß1 in fibroblasts infiltrating the frozen-thawed patellar tendon.Northern blot analysis showed that fibroblasts derived from the patellar tendon six weeks after the freeze-thaw procedure in situshowed less response to IL-1ß than normal tendon fibroblasts with respect to MMP-13 mRNA gene expression. The immunohistological findings revealed that IL-1ß was over-expressed in extrinsic fibroblasts which infiltrated the patellar tendon two and six weeks after the freeze-thaw procedure in situ, but neither PDGF-BB nor TGF-ß1 was over-expressed in these extrinsic fibroblasts. Our findings indicated that IL-1ß had a close relationship to matrix remodelling of the grafted tendon for ligament reconstruction, in addition to the commencement of inflammation during the tissue-healing process.

Velocity profiles in steady flows of fluid/particle mixtures through a duct with an abrupt contraction were measured by magnetic resonance imaging. Aqueous solutions of carboxymethyl cellulose containing particles, including spheres, disk‐like particles, and short fibers, at high volume fractions were used. As a result, a plug‐like velocity profile was observed in a straight duct flow for every suspension, but the velocity profile depends on the particle shape at contraction. Disk‐like particles caused an unsteady flow, and short fibers caused a concave shape in the velocity profile near the centerline upstream of the contraction. Spheres did not affect the flow field. The concave profile became obvious with increased volume fraction of fiber. This result is caused by the larger elongational viscosity of the fiber suspension near the centerline of the channel, as compared with that of the sphere suspension.

Background: The sentinel node (SN) concept has attracted considerable attention recently for the treatment of patients with early gastric cancer (EGC). This study evaluated the feasibility of laparoscopic SN navigation achieved by means of an infrared ray electronic endoscopy (IREE) system with indocyanine green (ICG) injection in patients with EGC. Methods: Laparoscopic SN navigation was performed for 16 patients with preoperatively diagnosed EGC. After identification of SNs, routine laparoscopically assisted distal gastrectomy with lymphadenectomy was performed. Lymph nodes were examined histologically for metastasis by hematoxylin and eosin staining on one section of each node. Results: One or more SNs and lymphatic basins were detected in all 16 patients. The average number of SNs detected was 2.9. Lymph node metastasis was found in 2 of the 16 patients (13%). In one of these two patients, lymph node metastasis was found in SNs. In the other patient, metastasis was found in a non-SN rather than a SN, but in the same lymphatic basin. The accuracy of this detection method was 94%, and there was one false-negative case. No adverse events occurred after injection of ICG. Conclusion: Laparoscopic SN navigation by means of IREE combined with ICG injection is feasible for patients undergoing laparoscopic surgery for EGC.

The termination of the superficial middle cerebral vein (SMCV) has been described as entering or being partially equivalent to the venous sinus coursing under the lesser sphenoid wing, which has classically been called the sphenoparietal sinus. However, the recent literature reports that the SMCV is not connected to the sphenoparietal sinus. In this study, the venous anatomy was evaluated to clarify the anatomy of the sphenoparietal sinus and the termination of the SMCV. Magnetic resonance imaging (MRI) was performed on 1.5-T superconductive units using a three-dimensional fast spoiled gradient-recalled acquisition in the steady state (3-D fast SPGR) sequence with fat suppression in a total of 48 sides of 24 patients. Coronal source images and reconstructed axial images were displayed on the Advantage Window Console, and connections to the cavernous sinus were then evaluated for the venous sinus coursing under the lesser sphenoid wing (hereafter called the sinus of the lesser sphenoid wing), the middle meningeal vein, and the SMCV.The following findings were observed bilaterally in all patients. The sinus of the lesser sphenoid wing was connected medially with the cavernous sinus and laterally with the anterior branch of the middle meningeal vein near the pterion.The anterior branch of the middle meningeal vein entered the bony canal laterally above the junction with the sinus of the lesser sphenoid wing and coursed along the inner table of the skull or emerged into the diploic vein, indicating its parietal portion. Although the termination of the SMCV had several patterns, the SMCV was not connected with the sinus of the lesser sphenoid wing in any of the patients. The sphenoparietal sinus is considered to consist of the sinus of the lesser sphenoid wing and the parietal portion of the anterior branch of the middle meningeal vein; these were identified as venous structures distinct to the SMCV.

In high heat input welding, such as 1-pass electrogas arc welding (EGW) of thick steel plates, HAZ toughness is deteriorated because HAZ microstructure coarsens significantly. TiN precipitates dispersed in steel plates are effective to suppress coarsening HAZ microstructure by pinning effect. However TiN precipitates resolve in high temperature region near the fusion line, where deterioration of HAZ toughness is unavoidable near the fusion line. As a solution of this problem, the authors paid attention to boron in the weld metal. Boron is known to be effective to prevent coarse ferrite formation at prior austenite grain boundaries, and to diffuse rapidly in steel. In this research, boron diffusion from weld metal to HAZ during EGW process was confirmed by SIMS analysis. It was certified that diffused boron in HAZ improved HAZ toughness because boron suppressed microstructure coarsening, and fixed free nitrogen originated by TiN resolution as BN near the fusion line. These research results proposed a new HAZ structure control technology considering combination of high boron bearing weld metal and TiN-treated steel plates.

We compared the results ten years after an inverted V-shaped high tibial osteotomy with those of a historical series of conventional closing-wedge osteotomies. The closing-wedge series consisted of 56 knees in 51 patients with a mean follow-up of 11 years (10 to 15). The inverted V-shaped osteotomy was evaluated in 48 knees in 43 patients at a mean follow-up of 14 years (10 to 19). All the patients were scored using the Japanese Orthopaedic Association rating scale for osteoarthritis of the knee and radiological assessment.The pre-operative grade of osteoarthritis was similar in both groups. Post-operatively, the knee function score was graded as satisfactory in 63% (35) of the closing-wedge group but in 89% (43) of the inverted V-shaped osteotomy group. Post-operative radiological examination showed that delayed union and loss of correction occurred more often after a closing-wedge osteotomy than after an inverted V-shaped procedure.Our study suggests that the inverted V-shaped osteotomy may offer more dependable long-term results than traditional closing-wedge osteotomy.

Digital subtraction angiography (DSA) and magnetic resonance imaging (MRI) findings in 20 patients with carotid-cavernous fistula (CCF; 3 direct CCFs and 17 indirect CCFs) were retrospectively reviewed to evaluate venous drainage patterns that may cause intracerebral haemorrhage or venous congestion of the brain parenchyma.We evaluated the relationship between cortical venous reflux and abnormal signal intensity of the brain parenchyma on MRI. Cortical venous reflux was identified on DSA in 12 of 20 patients (60.0%) into the superficial middle cerebral vein (SMCV; n=4), the uncal vein (n=2), the petrosal vein (n=2), the lateral mesencephalic vein (LMCV; n=1), the anterior pontomesencephalic vein (APMV; n=1), both the APMV and the petrosal vein (n=1) and both the uncal vein and the SMCV (n=1). Features of venous congestion, such as tortuous and engorged veins, focal staining and delayed appearance of the veins, were demonstrated along the region of cortical venous reflux in the venous phase of internal carotid or vertebral arteriography in six of 20 patients (30.0%). These findings were not observed in the eight CCF patients who did not demonstrate cortical venous reflux. MRI revealed abnormal signal intensity of the brain parenchyma along the region with cortical venous reflux in four of 20 indirect CCF patients (20%). Of these four patients, one presented with putaminal haemorrhage, while the other three presented with hyperintensity of the pons, the middle cerebellar peduncle or both on T2-weighted images, reflecting venous congestion. The venous drainage routes were obliterated except for cortical venous reflux in these four patients and the patients without abnormal signal intensity on MRI had other patent venous outlets in addition to cortical venous reflux.CCF is commonly associated with cortical venous reflux. The obliteration or stenosis of venous drainage routes causes a converging venous outflow that develops into cortical venous reflux and results in venous congestion of the brain parenchyma or intracerebral haemorrhage. Hyperintensity of brain parenchyma along the region of cortical venous reflux on T2-weighted images reflects venous congestion and is the crucial finding that indicates concentration of venous drainage into cortical venous reflux.

The plasma arc has a large arc force (regarded as the plasma force) and keyhole welding is generally performed by the formation of a small hole at the weld pool of a butt joint by making use of this plasma force. Under these circumstances, due to the small footprint area of the plasma heat source and welding by the formation of a keyhole, there is little melting at the joint zone and welding with a narrow bead width becomes feasible. Recently, a new type of plasma welding process has been proposed such that the welding tungsten electrode tip is brought close to the tip of the cooling chip and keyholeless welding is performed, similarly to TIG welding and this process has been made practicable.1 This process solves the disadvantages of keyhole welding while retaining the advantages of plasma welding and is capable of meeting the requirements of high speed welding. However, it is difficult to apply either method to fillet joints where keyhole formation is difficult due to the problems of the large plasma force and the torch structure. In either case, the large plasma force due to the plasma passing through the cooling chip small hole is surmised to be intimately associated with the weld morphology due to plasma welding.

We compared the biological characteristics of extrinsic fibroblasts infiltrating the patellar tendon with those of normal, intrinsic fibroblasts in the normal tendon in vitro. Infiltrative fibroblasts were isolated from the patellar tendons of rabbits six weeks after an in situfreeze-thaw treatment which killed the intrinsic fibroblasts. These intrinsic cells were also isolated from the patellar tendons of rabbits which had not been so treated.Proliferation and invasive migration into the patellar tendon was significantly slower for infiltrative fibroblasts than for normal tendon fibroblasts. Flow-cytometric analysis indicated that expression of a5ß1 integrin at the cell surface was significantly lower in infiltrative fibroblasts than in normal tendon fibroblasts. The findings suggest that cellular proliferation and invasive migration of fibroblasts into the patellar tendon after necrosis are inferior to those of the normal fibroblasts. The inferior intrinsic properties of infiltrative fibroblasts may contribute to a slow remodelling process in the grafted tendon after ligament reconstruction.

Purpose: The purpose of this study was to determine the acute effects of electrothermal shrinkage on the biomechanical properties of the anterior cruciate ligament (ACL). Type of study: Randomized trial. Methods: Fifty fresh femur-ACL-tibia complexes harvested from fully matured pigs were used. The femur-anteromedial bundle-tibia complex specimens were randomly divided into 5 groups of 10 specimens each. In each group, radiofrequency energy set at nonablative levels was applied to the anteromedial bundle of the ACL with a bipolar radiofrequency generator. In groups I and II, radiofrequency treatment was applied to the ACL using 28 W and 45 W power, respectively, for 30 seconds. In groups III and IV, radiofrequency treatment was applied to the ACL using 28 W and 45 W power, respectively, for 60 seconds. In group V, no treatment was applied in order to obtain normal control data. The treatment was performed in physiological saline solution under a 1-N load. In each group, 8 of the 10 specimens were used for biomechanical evaluation, and the remaining 2 were used for histologic observation. Results: Concerning the length of the anteromedial bundle after the treatment, the analysis of variance (ANOVA) showed a significant difference among the 5 groups. The length in groups I, II, III, and IV was significantly shorter than that of group V. In tensile testing, the stiffness was 120, 116, 113, 89, and 156 N/mm in groups I, II, III, IV, and V, respectively. The ANOVA showed a significant difference among the groups. Groups I, II, III, and IV were significantly lower than group V, respectively. Histologic examination showed diffuse collagenous denaturation and pyknotic nuclear changes in fibroblasts at the treated portion. The collagen crimp pattern was not present in the treated area. Conclusions: Application of RF energy to the specimens caused both shortening and weakening according to the magnitude and duration of the application. Clinical relevance: These results may explain one of the causes of the poor results reported in some clinical studies. This study warns against a too optimistic application of electrothermal shrinkage to the ACL as a clinical treatment.

Background Conventional open gastrectomy has been reported to result in increased morbidity in obese patients. To date, there has been no study evaluating laparoscopic gastrectomy in such patients; therefore, we assessed the short-term results of this procedure in a group of obese patients. Methods The study included 99 consecutive patients who underwent laparoscopy-assisted distal gastrectomy (LDG) for the cure of early gastric cancer. The patients were divided into two groups: obese (body mass index [BMI] ≥25.0, n = 16) and nonobese (BMI <25.0, n = 83). Patient characteristics, operative details, and postoperative outcomes were compared and analyzed. Results Patient characteristics, including age, sex, American Society of Anesthesiologists (ASA) status, and disease stage, were not different between obese and nonobese patients. Operating time was significantly longer in obese patients than in nonobese patients (271 vs 239 min, p < 0.05). However, there was no significant difference between obese and nonobese patients in time to first flatus (3.7 vs 3.3 days), time to solid diet (6.3 vs 5.2 days), length of postoperative hospital stay (18.7 vs 17.9 days), or frequency of major (25% vs 16%) and minor (19% vs 12%) postoperative complications. There were no conversions to conventional open surgery and no perioperative deaths. Conclusion The only difference between our two study groups was that LDG required a longer operating time in obese patients; morbidity and length of hospital stay were not increased. Thus, we believe that LDG is likely to become the treatment of choice for obese patients with early gastric cancer.

A basic-leucine zipper transcription factor, MafA, was recently identified as one of the most important transactivators of insulin gene expression. This protein controls the glucose-regulated and pancreatic beta-cell-specific expression of the insulin gene through a cis-regulatory element called RIPE3b/MARE (Maf-recognition element). Here, we show that MafA expression is restricted to beta-cells of pancreatic islets in vivo and in insulinoma cell lines. We also demonstrate that c-Maf, another member of the Maf family of transcription factors, is expressed in islet alpha-cells and in a glucagonoma cell line (alphaTC1), but not in gamma- and delta-cells. An insulinoma cell line, betaTC6, also expressed c-Maf, albeit at a low level. Chromatin immunoprecipitation assays demonstrated that Maf proteins associate with insulin and glucagon promoters in beta- and alpha-cell lines, respectively. c-Maf protein stimulated glucagon promoter activity in a transient luciferase assay, and activation of the glucagon promoter by c-Maf was more efficient than by the other alpha-cell-enriched transcription factors, Cdx2, Pax6, and Isl-1. Furthermore, inhibition of c-Maf expression in alphaTC1 cells by specific short hairpin RNA resulted in marked reduction of the glucagon promoter activity. Thus, c-Maf and MafA are differentially expressed in alpha- and beta-cells where they regulate glucagon and insulin gene expression, respectively.

AbstractProper eye formation depends on specific interactions between neural and ectodermal tissues coupled with temporally distinct gene expression and a regulated sequence of signaling events. The homeobox gene Pax6 is vitally important to the entire process of eye development in both vertebrates and invertebrates. Pax6 expression for the retina anlage has been shown to be indispensable in the development of various retinal cells. Here, we report that Pax6 expression in neural tissue plays an important role in lens development. Expression of a dominant-negative version of Pax6 isoform that lacks 5a-exon sequence in developing optic vesicles (OV) of chick embryos led to arrest of lens development at the lens vesicle stage as well as optic cup deformation. To gain insights into the molecular events underlying deformed lens formation, we examined the expression of several transcription factors in the lens of Pax6-negative-OV eye. Importantly, L-Maf was downregulated while c-Maf was found normal in deformed lens. We detected a downregulation of fibroblast growth factor (FGF8) in the neural tissue. Our in vivo experiments suggest that Pax6 in neural retina regulates FGF8 expression, which may maintain L-Maf expression in the lens to be essential for later lens fiber differentiation.Copyright © 2004 S. Karger AG, Basel

The steroid hormone progesterone is a key factor in establishment and maintenance of pregnancy in the human endometrium. To obtain a global view and identify new target genes for progesterone in human endometrial stromal cells in short-term (3 days) culture, we used a screening strategy to analyze the expression of nearly 1000 human genes by DNA microarray analysis. The results showed that six genes were up-regulated (at least a two-fold increase), and 27 genes were down-regulated (at least a two-fold decrease) after progesterone treatment compared with control. Progesterone stimulated the expression of the interleukin (IL)-1 receptor type 1, fibulin-1, fibulin-2, microsomal glutathione S-transferase 1, fumarylacetoacetate hydrolase and orphan G protein-coupled receptor (RDC1). Progesterone inhibited the expression of insulin-like growth factor binding protein-5, heparin-binding epidermal growth factor-like growth factor, and IL-13 receptor α2. In addition, progesterone inhibited the expression of genes involved in immune modulators, DNA/chromatin-related proteins, signal transduction, transcription factors, transport proteins, enzyme, receptor and structural proteins. Our results demonstrate that microarray analysis can be used to identify progesterone-regulated genes in endometrial stromal cells, thus contributing to a more detailed understanding of the molecular mechanisms in response to progesterone in the endometrium during the preparatory period for implantation.

Abstract: The growth characteristics and crystalline quality of thick (100) CdTe-epitaxial layers grown on (100) GaAs and (100) GaAs/Si substrates in a metal-organic vapor-phase epitaxy (MOVPE) system for possible applications in x-ray imaging detectors were investigated. High-crystalline-quality epitaxial layers of thickness greater than 100 m could be readily obtained on both types of substrates. The full width at half maximum (FWHM) values of the x-ray double-crystal rocking curve (DCRC) decreased rapidly with increasing layer thickness, and remained around 50–70 arcsec for layers thicker than 30 m on both types of substrates. Photoluminescence (PL) measurement showed high-intensity excitonic emission with very small defect-related peaks from both types of epilayers. Stress analysis carried out by performing PL as a function of layer thickness showed the layers were strained and a small amount of residual stress, compressive in CdTe/GaAs and tensile in CdTe/GaAs/Si, remained even in the thick layers. Furthermore, the resistivity of the layers on the GaAs substrate was found to be lower than that of layers on GaAs/Si possibly because of the difference of the activation of incorporated impurity from the substrates because of the different kinds of stress existing on them. A heterojunction diode was then fabricated by growing a CdTe epilayer on an n+-GaAs substrate, which exhibited a good rectification property with a low value of reverse-bias leakage current even at high applied biases.

Previous studies have demonstrated that myocardial perfusion imaging using 99mTc-tetrofosmin at rest allows viability assessment similar to that obtained with 201Tl imaging and 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET). The simultaneous assessment of perfusion and regional function is now available by quantitative gated myocardial perfusion single-photon emission computed tomography (SPECT). This study was designed to evaluate the utility of quantitative values of wall motion and wall thickening, calculated by quantitative gated myocardial perfusion SPECT, for the prediction of functional recovery after coronary bypass grafting (CABG). Fifty-six patients with coronary artery disease scheduled for CABG were included prospectively. All patients underwent 99mTc-tetrofosmin gated SPECT imaging at rest preoperatively and 3 months after CABG. The myocardium was divided into nine segments and the average quantitative values of regional perfusion (percentage uptake) (), wall motion (mm) and wall thickening () were determined automatically using quantitative gated SPECT (QGS) software. The wall motion score was defined visually using a four-point scale (0, normal; 3, akinesis), and segments with severe asynergy (score of 2 or 3) with patent grafts were assessed. Of 77 segments with severe asynergy, 56 segments showed improved wall motion and 21 segments did not improve after CABG. The area under the receiver operating characteristic curve of wall thickening for the prediction of functional recovery was significantly higher (0.92) than that of the percentage uptake (0.77, P<0.017) or wall motion (0.60, P<0.0001). When each analysis used the optimal threshold, the wall thickening analysis (10) had a sensitivity of 95 and a specificity of 81. These values tended to be higher than those of the percentage uptake (sensitivity, 86; specificity, 67). The wall motion analysis (1.5 mm) had a significantly lower sensitivity of 75 and specificity of 43 than the wall thickening analysis (P0.0038 and P0.011, respectively). The results indicate that wall thickening, calculated by QGS software, may be more useful than regional perfusion or wall motion analysis for the prediction of functional recovery after CABG. The areas of asynergy with relatively preserved wall thickening may have the potential for improved function despite severely decreased perfusion.

We have developed a simple method for reconstructing a three-dimensional (3D) image in the operating room from sequentially scanned intraoperative two-dimensional (2D) power Doppler images using a personal computer and commercially available software. During three operations, 2 for cerebral aneurysm and 1 for cerebral tumor, intracranial vessel images were digitally transferred to a personal computer by freehand scanning over the dura mater or surface of the brain with a 7.5-MHz linear probe. A series of 2D images were converted to a smaller file, and 3D image was reconstructed with volume-rendering software. It took about 15 minutes to reconstruct of the initial 3D image. In the cases of cerebral aneurysm, the vessels connected to the lesion or running nearby were easily identified on the image. In the tumor case, the anatomical relation between the vascular structures and the tumor was clear. This simple 3D reconstruction method provides spatial information about intracranial vascular structures that is useful in intraoperative surgical planning.

Chromatographic separation of an extract of the bulbs of Scilla sibirica resulted in the isolation of five pyrrolidines, two pyrrolidine glycosides, six piperidines, one piperidine glycoside, and eight pyrrolizidines. 2,5-Dideoxy-2,5-imino-glycero-d-manno-heptitol (homoDMDP, 1) is a common alkaloid in all plants of the Hyacinthaceae examined to date and was also found in S. sibirica. The structures of the new alkaloids were elucidated by spectroscopic methods as 7-deoxy-homoDMDP (4), 2,5-dideoxy-2,5-imino-glycero-d-galacto-heptitol (5), the 4-O-β-d-mannoside (6) and the 4-O-β-d-mannobioside (7) of 6-deoxy-homoDMDP (2), 7-deoxyhomonojirimycin (12), 7-deoxyhomomannojirimycin (13), and polyhydroxypyrrolizidines, hyacinthacines A4 (15), A5 (16), A6 (17), A7 (18), B4 (20), B5 (21), and B6 (22). HomoDMDP (1) is a potent inhibitor of β-glucosidase and β-galactosidase, while 6-deoxy-homoDMDP (2) showed significantly less inhibition. However, 7-deoxygenation of 1, leading to 4, showed no effect on the inhibitory activity toward both enzymes. Although 2 is not an inhibitor of α-l-fucosidase, the monomannoside of 2 shows inhibitory activity toward α-l-fucosidase. Elongation of the β-mannopyranosyl chain of 6 to give 7 enhanced the inhibitory activity.

Abstract: Iodine doping of CdTe layers grown on (100) GaAs by metal-organic vapor phase epitaxy (MOVPE) was studied using diethyltelluride (DETe) and diisopropyltelluride (DiPTe) as tellurium precursors and ethyliodine (EI) as a dopant. Electron densities of doped layers increased gradually with decreasing the growth temperature from 425C to 325C. Doped layers grown with DETe had higher electron densities than those grown with DiPTe. When the hot-wall temperature was increased from 200C to 250C at the growth temperature of 325C, doped layers grown with DETe showed an increase of the electron density from 3.71016 cm−3 to 2.61018 cm−3. On the other hand, such an increase of the electron density was not observed for layers grown with DiPTe. The mechanisms for different doping properties for DETe and DiPTe were studied on the basis of the growth characteristics for these precursors. Higher thermal stability of DETe than that of DiPTe was considered to cause the difference of doping properties. With increasing the hot-wall temperature from 200C to 250C, the effective ratio of Cd to Te species on the growth surface became larger for layers grown with DETe than those grown with DiPTe. This was considered to decrease the compensation of doped iodine and to increase the electron density of layers grown with DETe. The effective ratio of Cd to Te species on the growth surface also increased with decreasing growth temperature. This was considered to increase the electron density with decreasing growth temperature.

We performed a biomechanical and histological study to clarify the effect of stress enhancement on the in situ frozen-thawed patellar tendon of the rabbit as a tendon autograft model. We used 48 Japanese White rabbits divided into three groups. In group 1, the patellar tendon underwent in situ freeze-thaw treatment with liquid nitrogen to kill intrinsic fibroblasts. In group 2, after similar treatment, the medial and lateral portions were resected so that the cross-sectional area was reduced by a third. In group 3, after treatment, the cross-sectional area was reduced by a half. In groups 2 and 3, the stress in the tendon was calculated theoretically to be 150% and 200% of the physiological stress during locomotion.Eight rabbits in each group were killed at three and six weeks, respectively. At three weeks, the mean values for the tensile strength of groups 2 and 3 were 113.7% and 75.7% of that of group 1, and at six weeks 101.2% and 57.4%, respectively. The tensile strength in group 3 was significantly lower than that in groups 1 and 2. The histological findings in group 2 were similar to those in group 1, although an acellular area appeared to be wider in the core portion compared with group 1 at each period. In group 3, the collagen bundles of the tendon were less organised than those of groups 1 and 2.Our findings showed that stress enhancement affects the remodelling of the frozen-thawed patellar tendon and that excessively high stress reduces the mechanical properties of the tendon. This indicates that high stress on the patellar tendon autograft should be avoided during ligament reconstruction.

Chromatographic separation of the pod extract of Angylocalyx pynaertii resulted in the isolation of 13 sugar-mimic alkaloids (1−13). The structures of the new alkaloids were elucidated by spectroscopic methods as the 6-O-β-d-glucoside (10) and N-hydroxyethyl derivative (11) of 1,4-dideoxy-1,4-imino-d-arabinitol (DAB) (1), 1,6-dideoxynojirimycin (12), and 1,3,4-trideoxynojirimycin (13). 2,5-Imino-1,2,5-trideoxy-l-glucitol (7), 2,5-dideoxy-2,5-imino-d-fucitol (8), and β-homofuconojirimycin (9), isolated from the pods as well as the bark, were very specific inhibitors of α-l-fucosidase with no significant inhibitory activity toward other glycosidases. In this work, 1,4-dideoxy-1,4-imino-d-ribitol (6) was found to be a better inhibitor of lysosomal β-mannosidase than 2,5-imino-1,2,5-trideoxy-d-mannitol (2). N-Hydroxyethyl-1-deoxynojirimycin (miglitol), which is commercially available for the treatment of diabetes, retained its inhibitory potential toward rat intestinal maltase and sucrase, whereas 11 and the synthetic N-hydroxyethyl derivative of 2,5-dideoxy-2,5-imino-d-mannitol markedly lowered or abolished their inhibition toward all enzymes tested.

An IrO2/Pt electrocatalyst for the polymer electrolyte-type unitized regenerative fuel cell (URFC) was prepared by deposition of iridium oxide (IrO2) particles on Pt black via a colloidal iridium hydroxide hydrate precursor, and URFC performance was examined. After the iridium hydroxide hydrate deposited Pt was calcined at 400 °C in air for 1 h, rutile-structure IrO2particles (20–50 nm dia.) were formed on Pt particle clusters. TEM and pore volume distribution analysis revealed that the microstructure of the deposited IrO2/Pt catalyst was different from the mixed IrO2/Pt catalyst. The cell using the deposited IrO2/Pt (20 at % Ir) catalyst showed similar fuel cell performance with the mixed IrO2/Pt electrode of higher Pt content (10 at % Ir) while maintaining water electrolysis performance. Consequently, 51% round-trip energy conversion efficiency at a current density of 300 mA cm−2was attained.