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Solid lubricants have long been widely used to enhance lubricity and to achieve a longer die life in the field of tribological applications. Molybdenum disulfide (MoS 2 ) is the most desirable solid lubricant because of its low friction coefficient, good anti-seizure ability stemming from easy cleavage and excellent adhesion to the metal surface. Although MoS 2 performs well, it has a disadvantage in that its black appearance significantly stains the working environment. Therefore, non-black solid lubricants are strongly desired. Herein, we investigated the properties of a clay-organic intercalation compound as a solid lubricant. It is well known that some types of layered clay minerals have a cation exchange capacity and are capable of being intercalated with an organic cation between the silicate layers. This reaction is based on the ion exchange of exchangeable inorganic ions (Na + , K + , etc.) in the layered clay minerals. In this study, we examined the properties of synthetic mica, whose silicate layers were intercalated with a cationic organic compound (dioctadecyl dimethyl ammonium chloride). We evaluated the lubrication performance of the mica using a newly devised upsetting-ironing type tribometer. X-ray diffraction (XRD) results show that the distance between the silicate layers of the intercalated synthetic mica increased to 36.6 A from 12.6 A for a non-intercalated one. Owing to the increase in the interlayer distance, the lubrication coating containing the synthetic mica-organic intercalation compound showed a much improved lubrication performance than that of the non-intercalated one. These findings indicate that the lubricity of the clay minerals is highly dependent on the friction between the different silicate layers, and that the cationic organic compound incorporated into the interlayers can improve the lubricity. This result means that the clay-organic intercalation compound is a promising solid lubricant as an alternative to MoS 2 .

A micro-electro-mechanical-system internal combustion engine (MEMS IC engine) is fabricated to demonstrate the energy conversion from heat to mechanical power. The dimensions and surface-to-volume ratio of combustion chamber are 5 mm × 3 mm × 1 mm (0.015 cc) and 3.07 mm −1 , respectively. The reciprocation motion of a piston can be sustained by the force balance between combustion pressure and the repulsion force of an elastic spring. A premixture gas composed of hydrogen and oxygen is used for fuel under stoichiometric combustion (equivalent ratio is 1). The combustion is confirmed by pressure measurement and the direct observation of flame propagation. A high-speed CMOS camera is adopted for the flame observation. A maximum combustion pressure of 142.6 kPa, a displacement of 9.5 mm 3 , and a mechanical power of 29.1 mW were obtained for the MEMS IC engine. This experimental evidence provides a positive outlook for the materialization of the MEMS heat engine concept.

OBJECTIVE To examine the immunoreactivity of tumors for matrix metalloproteinases 2 and 9 (MMP-2, MMP-9), tissue inhibitors of metalloproteinases 1 and 2 (TIMP-1, TIMP-2), and membrane type MMP 1 (MT-MMP-1), to evaluate the optimum assessment of incidental renal cell carcinoma. METHODS Tumor samples from 120 incidental clear cell renal cell carcinoma (ICRCC) patients without distant metastasis or invasion beyond Gerota's fascia were obtained by surgery. They were immunohistochemically stained for MMP-2, MMP-9, TIMP-1, TIMP-2, and MT-MMP-1. Immunoreactivity for these factors was analyzed by semiquantitative multivariate analysis for cancer-specific survival. RESULTS The cancer-specific 5 and 10-year survival rates were 91.4% and 91.4%, respectively. Univariate analysis revealed that nuclear grade (P = 0.0064) and TIMP-2 (P = 0.034) were significant prognostic factors. Matrix metalloproteinase 9 has a significant relationship with high nuclear grade RCC (P = 0.017) and was found to be an independent prognosticator by Cox multiple regression analysis (P = 0.0028). CONCLUSIONS Nuclear grade and TIMP-2 were significant prognostic factors of ICRCC. Multivariate analysis showed that a nuclear grade greater than 3 was associated with a 566% significant increase in the odds of cancer death. Strong expression of MMP-9 was associated with a 774% increase in the odds of high nuclear grade, with statistical significance. Although ICRCC is well known for having a favorable prognosis, patients with tumors having a high nuclear grade and strongly expressed MMP-9 and TIMP-2 should undergo strict postoperative follow-up.

Purpose: Forme fruste choledochal cyst (FFCC) is a choledochal cyst that has minimal or no dilatation of the extrahepatic bile duct (EHBD) and is associated with pancreaticobiliary malunion (PBMU). The authors reviewed the long-term outcome of their patients with FFCC. Methods: Inpatient and outpatient records of 281 patients with choledochal cyst were reviewed. In this study, minimal dilatation of the EHBD was defined as its maximum diameter being less than 10 mm. Results: There were 17 cases of FFCC identified. In all 17 patients, PBMU was present. The mean age at EHBD excision was 2.9 years. Fourteen patients had hepatico-jejunostomy, and three had hepatico-duodenostomy. The histology of the excised EHBD showed mucosal ulceration/sloughing (in 35.3% patients), fibrosis (52.9%), and inflammatory cell infiltration (41.2%). Over a mean postoperative follow-up period of 9.8 years, there have been no episodes of cholangitis or anastomotic stricture formation. Conclusions: The treatment of choice for FFCC in children is EHBD excision and hepatico-jejunostomy. There is little surgical morbidity if performed carefully.

Objective. To examine blood-flow change and recovery of sensibility in the dental pulp of maxillary incisors in patients undergoing a single-segment Le Fort I osteotomy. Study Design. Fifty-four maxillary incisors in 14 patients were examined preoperatively and at 1 to 7 days, 14 days, 3 months, 6 months, and 12 months postoperatively. The pulpal blood flow (PBF) was measured by laser Doppler flowmetry, and the pulpal sensibility (PS) was investigated by electrodiagnostics. Results. The mean PBF dropped to its lowest value at 1 day postoperatively and subsequently increased except for a temporary drop on day 4. The PS was negative in all the examined teeth from 1 day to 14 days after surgery. Subsequently, the rate of the teeth with positive PS increased. At 3 months postoperatively, the PS recovered in half of the examined teeth. The PBF value on day 1 was significantly higher in the teeth with positive PS at 3 months postoperatively than in those with negative PS at 3 months postoperatively. Conclusion. These results suggest that the decrease of the PBF in the maxillary incisors on 1 day after a single-segment Le Fort I osteotomy may affect the recovery of the PS in the short term after surgery. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2003;95:660-4)

Background: hepatic functional reserve is determined by the function and number of hepatocytes, as well as hepatic blood flow. In Japan, endoscopic injection sclerotherapy is often performed prophylactically in patients with high-risk esophageal varices. We examined the effects of blocking portosystemic shunts by this treatment on hepatic circulation and hepatocyte function as evaluated by 99mTc-GSA scintigraphy (HH15, LHL15), an examination via asialoglycoprotein receptors on hepatocytes. Methods: forty-nine patients who underwent prophylactic treatment of esophageal varices were divided into two groups; one having esophageal varices alone and the second having other collateral circulation in addition to esophageal varices. Asialoscintigraphy and general liver function tests were performed both before and after treatment in each group and the data were statistically analyzed. Results: In the group having esophageal varices alone, serum total bile acid significantly decreased at 62.2% and ICGR15, HH15, and LHL15 were slightly improved at -10.9, -3.0, and +4.7%, respectively, after sclerotherapy (P0.01). However, Child-Pugh's score was not changed after sclerotherapy. In the group having additional collaterals, no parameters were changed after sclerotherapy. Conclusion: we demonstrate that HH15, LHL15, and ICGR15 are partially influenced by hepatic circulation but are mainly determined by the function of hepatocytes, whereas serum total bile acid is markedly influenced by hepatic circulation.

To investigate the reversibility of neuronal functions during deep and mild hypothermia, we have examined changes in membrane properties of pyramidal neurons of the CA3 region of hippocampal slices during cooling and rewarming (8 approximately 37 degrees C) of the perfusion medium. Hypothermia reduced the excitatory postsynaptic potential (EPSP) slope in a temperature dependent manner, but the EPSP amplitude was enhanced transiently between 30 and 25 degrees C. In observing spikes generated by either orthodromic stimulation or by direct intracellular current injection, the critical threshold for spike generation was decreased transiently at a temperature of 30 degrees C. In addition, the numbers of spikes were increased transiently regardless of the progressive prolongation of spike duration and latency with cooling. The resting membrane potential was stable from 37 to 20 degrees C. However, this potential showed a depolarizing shift at 15 degrees C. The neuronal activities, including membrane properties, recovered fully when the temperature was raised to 35 degrees C even from a low of 15 degrees C. In addition, field population spikes (PS) recorded in the pyramidal cell layer showed a complete reversibility after long-term severe hypothermia (8 degrees C). These results suggest that synaptic function, neuronal excitability and membrane properties maintain reversibility during deep hypothermia, as well as in mild hypothermia.

A compact chemical analysis (pulse radiolysis) apparatus using a BNL-type s-band photocathode RF gun (GUN-IV) is now under development at Sumitomo Heavy Industries (SHI). Using the apparatus, fast chemical reactions induced by 3.5 ps pulse of electron beam can be analyzed by means of time-resolved photo-absorption spectroscopy with 10 ps laser pulses in the wavelength range of 210–2000 nm. The high-precision control of RF phase makes 10 ps of time-resolution possible for the analysis.

The upper and the lower bounds of the lightest CP-even Higgs-boson mass ($m_h$) are discussed in the two-Higgs-doublet model (2HDM) with a softly-broken discrete symmetry. They are obtained as a function of a cut-off scale $\Lambda$ ($\leq 10^{19}$ GeV) by imposing the conditions in which the running coupling constants neither blow up nor fall down below $\Lambda$. In comparison with the standard model (SM), although the upper bound does not change very much, the lower bound is considerably reduced. In the decoupling regime where only one Higgs boson ($h$) becomes much lighter than the others, the lower bound is given, for example, by about 100 GeV for $\Lambda = 10^{19}$ GeV and $m_t = 175$ GeV, which is smaller by about 40 GeV than the corresponding lower bound in the SM. In generic cases, $m_h$ is no longer bounded from below by these conditions. If we consider the $b \to s \gamma$ constraint, small values of $m_h$ are excluded in Model II of the 2HDM., Comment: 13 pages, 5 figures, extend the analysis to the case without restriction among self-coupling constants. Conclusions unchanged. To appear in Phys. Lett. B

We investigate the effect of supersymmetric CP violating phases on the $B\to X_s \gamma$ and $B\to X_s l^+l^-$ decays in the minimal supergravity model. We show that the phase of the trilinear scalar coupling constant for top squarks is strongly suppressed and aligned to that of the gaugino mass due to a renormalization effect from the Planck scale to the electroweak scale. As a result, the effect of supersymmetric CP violating phases on the $B \to X_s \gamma$ and $B \to X_s l^+ l^-$ decays are small taking into account the neutron and the electron electric dipole moment constraints. For the $B \to X_s\gamma$ decay, the amplitude has almost no new CP violating phase and the direct CP asymmetry is less than 2 %. For the $B \to X_s l^+ l^-$ decay, the branching ratio can be sizably different from that in the standard model only when the sign of the $B \to X_s \gamma$ amplitude is opposite to that in the standard model.

NMDA produced whole-cell membrane currents in cultured human astrocytes. The currents were not inhibited by the selective NMDA receptor antagonist, APV, while they were partially inhibited by the broad G-protein inhibitor, GDPbetaS. NMDA-induced currents were enhanced by either the microsomal Ca2+/ATPase inhibitors, thapsigargin and cyclopiazonic acid, or the ATP-uncoupler, dinitrophenol (DNP). In the Ca2+ assay, NMDA increased intracellular calcium concentration. The increase was inhibited by 26% in Ca2+-free extracellular solution, and it was not inhibited by APV. The results of the present study suggest that NMDA responses in human astrocytes are regulated by store Ca2+ depletion-associated signal.

Neurotransmission in the superior colliculus (SC) and the hippocampus is enhanced by application of adenosine. To investigate the possibie involvement of disinhibition by adenosine on γ -aminobutyric acid (GABA) -ergic action, the effects of adenosine and picrotoxin, a GABA antagonist, were studied using slices of SC and hippocampus of the guinea pig. Application of adenosine on SC slices (concentration at 100 μ M) and hippocampus (concentration at 0.1 μ M) enhanced the amplitude of population spikes (PS) in the superficial gray layer (SGL) of SC and in the granule cell layer of dentate gyrus of hippocampus. The application of picrotoxin at 100 μ M increased the amplitude of both slices even after previous treatment with adenosine which once increased the amplitude. This was also true for adenosine with the previous treatment of picrotoxin. In SC slices, the increased amplitude by adenosine was reduced to the original amplitude after application of 3-[1-[3-(Dimetylamino) propyl]-1H-indol-3-yl-]4-(1H-indol-3-yl)-1H-pyrrole-2,5-dione (GF109203X) a protein kinase C inhibitor, the previous treatment by the drug counteracted the excitatory action of adenosine. However GF109203X failed to counteract the excitatory effects of picrotoxin. These results indicate that the excitatory mechanism of adenosine is different from that of picrotoxin and is not mediated by disinhibition of the GABAergic system through inhibitory action of adenosine on GABAergic interneurons.

Background: Studies have shown that total parenteral nutrition (TPN) in infancy is associated with impaired immunity. The causes of this acquired immunodeficiency are poorly understood. Bacterial infection is a major complication of TPN suggesting neutrophils may be affected by this feeding modality. Purpose: The aim of this study was to test the hypothesis that TPN-related impaired bactericidal activity is related to impairment of neutrophil function, particularly intracellular killing. Methods: Studies were performed in five infants (age 10 days), five control infants who received a normal enteral diet, and five healthy adults. Patients on long-term TPN were clinically stable with no evidence of sepsis. The experimental study used an in vitro whole-blood model of septicaemia. Coagulase-negative staphylococci were the bacterial challenge. Whole-blood killing of coagulase-negative staphylococci was measured after 45 minutes using the Miles-Misra technique. Neutrophils were separated from whole blood after 15, 30, 45, and 60 minutes of bacterial challenge. The survival rate of the bacteria within the neutrophils was analysed by flow cytometry and the percentage of the bacteria killed by neutrophil intracellular killing assessed at each time-point. Results: Whole-blood killing was significantly lower ( P = .05) in infants who received long-term TPN (33.3%) compared with control infants (69.7%) and adults (67.7%). In all subjects studied, neutrophil intracellular killing increased with incubation time. At each time point the intracellular killing in infants on long-term TPN was significantly lower ( P Conclusion: Future strategies to prevent TPN-related infection should aim to minimise this acquired neutrophil dysfunction.

Previous studies have shown that total parenteral nutrition (TPN) influences host immunity, but the mechanism is unclear. This study explored the effect of TPN solution on neutrophil phagocytosis and whole-blood cytokine production in response to coagulase-negative staphylococci in vitro challenge.Blood samples were taken from five enterally fed infants (age6 months) and six healthy adults. Samples were incubated for 45 minutes with four isovolemic solutions: (A) control (saline), (B) TPN (0.1 microL/mL of blood), (C) TPN (1 microL/mL), (D) TPN (10 microL/mL). Solution C (1 microL/mL) corresponded to TPN-blood ratio used in clinical practice. After incubation, blood was challenged with coagulase-negative staphylococci. Neutrophil phagocytosis was measured by flow cytometry after 40 minutes of bacterial challenge, and tumour necrosis factor alpha (TNF-alpha) was measured by enzyme-linked immunosorbent assay (ELISA) after 2 hours of bacterial challenge.In infant blood, TNF-alpha production after coagulase-negative staphylococci challenge was impaired after the addition of a "physiological" dose of TPN solution (1 microL/mL of blood) as well as "supranormal" doses (10 microL/mL of blood). In adult blood, a similar effect was observed only after the addition of a supranormal dose of TPN. In both the infant and adult blood, there was no direct effect of TPN solution on neutrophil phagocytosis.These results suggest that infants are more susceptible than adults to TPN-related depression of cytokine production. The level of proinflammatory cytokines may be important in the host defence against bacterial infection.

Using a wedge-type cubic-anvil high pressure apparatus, ternary rhodium silicides MRhSi (M=Ti, Zr and Hf) and alloys ZrRh 1− x Ru x Si ( x =0.1, 0.3 and 0.5) with a Co 2 P-type orthorhombic structure have been prepared by reaction of stoichiometric amounts of each metal and silicon powders at around 4 GPa and above 1200°C. The electrical resistivity and the d.c. magnetic susceptibility of the ternary rhodium silicides and the alloys have been measured at low temperatures. Superconducting transition temperatures ( T c ) in MRhSi (M=Ti, Zr and Hf) are 5.1, 10.3 and 2.3 K, respectively. These ternary rhodium silicides are new superconductors. The T c (=10.3 K) of ZrRhSi is highest among many compounds with the Co 2 P-type structure.

The purpose of this present study is to clarify adenosine (ADO) metabolism in guinea pig brain slices during simulated ischemia. In slice preparations after decapitation, ADO levels were lowest in slices of the cerebellum (1.2 nmol/mg protein), followed by the superior colliculus (3.4) and highest in the hippocampus (6.4), and the combined concentrations of inosine (Ino) and hypoxanthine (HX) were highest in the cerebellum (5.5), followed by the superior colliculus (3.5) and the hippocampus (1.5). After preincubation with standard medium with oxygen and glucose for 30 min, total ADO levels (tissue ADO plus ADO lost into medium during incubation) decreased to 0.3 in the cerebellum, to 1.3 in the superior colliculus and to 2. 9 in the hippocampus. On the other hand, levels of total Ino and HX increased to 21.1 in the cerebellum, to 14.3 in the hippocampus and to 12.0 in the superior colliculus. To investigate the effect of simulated ischemia on ADO metabolism, preincubated slices were exposed for 10 min in medium deprived of oxygen and glucose. The increases of ADO content after 10 min ischemia were 0.2 in the cerebellum, 1.0 in the superior colliculus and 1.3 in the hippocampus. In contrast, the increases of both Ino and HX concentrations were 2.9 in the cerebellum, 2.2 in the superior colliculus and 1.4 in the hippocampus. The total amount of the increase in ADO, Ino and HX was approximately 3 in all three regions. These results indicate that there are significant differences in the metabolic rate to degrade ADO into Ino and HX in various areas of brain possibly due to differences in adenosine deaminase activity in those areas.

Changes in levels of adenosine, inosine, hypoxanthine and ATP during complete ischemia after decapitation were determined in various areas of the guinea pig and rat brain using an HPLC method. These results were compared with levels in brains fixed by microwave irradiation. The levels of adenosine during 60 min of complete ischemia were extremely high and unevenly distributed while levels in the microwaved brains were very low and evenly distributed. The ratios of inosine plus hypoxanthine levels to adenosine which indicate the rate of metabolic degradation from adenosine into inosine and hypoxanthine, were also unevenly distributed during complete ischemia in the cerebellum, superior colliculus, cerebral cortex and hippocampus of the guinea pig and rat, and the highest ratio was observed in the cerebellum of the guinea pig and the superior colliculus of the rat. The activities of adenosine deaminase (ADA), one of the enzymes involved in adenosine metabolism, were measured in the four regions of the guinea pig. The ADA activities were unevenly distributed and the highest ADA activity was found in the cerebellum. These regional differences in ADA activities are in good agreement with the regional differences in the ratio of inosine plus hypoxanthine levels to adenosine during complete ischemia. Furthermore, the administration of EHNA [erythro-9-(2-hydroxy-3-nonyl)adenine hydrochloride] (10 mg/kg, i.p.), an ADA inhibitor, caused a significant increase of adenosine and decrease of inosine formation in all four regions and a drastic effect on the cerebellum with high ADA activity compared with the other regions in the guinea pig brain. These results indicate that the changes in concentrations of adenosine and its metabolites (inosine and hypoxanthine) during complete ischemia depend on ADA activity in each brain region.

Using hippocampal slices from guinea pigs, we investigated the effect of different concentrations of glucose and replacement of glucose with mannose, fructose and lactate on neural activity. As an index of neural activity, the population spikes (PS) were recorded in the granule cell layer of the dentate gyrus (DG) and the pyramidal cell layer of the CA3 area in the hippocampal slices. Lowering the concentration of glucose from 10 mM to 5, 3, 2, 1 and 0 mM caused a reduction in the PS amplitude. There were differences in the decay times of the PS evoked in these two regions. PS evoked in CA3 region decayed faster even at a concentration of 3 mM glucose at which PS in granule cell layer was well maintained. The decay time of the PS in the CA3 region in the presence of glucose up to a concentration of 3 mM was shorter than that evoked in the DG. After the replacement of glucose with mannose, fructose or lactate, the PS disappeared within 35 min and there were no significant differences between the decay times in the two regions of slices incubated in the same medium. ATP, creatine phosphate (CrP) and lactate levels in each slice were determined. To investigate whether mannose and fructose could be metabolized or not in the tissue slice, anaerobic production of lactate from glucose, mannose and fructose were measured during oxygen and glucose deprivation. Under anaerobic conditions for 60 min, the levels of high-energy phosphates decreased to 50% of the initial level and lactate was produced from glucose, mannose or fructose. However, there were significant differences in the rate of lactate production between the DG and CA3 areas during application of 3 mM glucose, 10 mM mannose and 10 mM fructose. These results indicate that mannose, fructose and lactate can be metabolized and are available for maintaining the levels of high-energy phosphates but not for neural activity in the tissue slices and that the presence of glucose is indispensable for the maintenance of neural activity.

Parenteral nutrition (PN) is associated with a risk of septicaemia. This may be caused by impairment of immune function related to PN. The authors investigated the effects of the addition of enteral feedings to PN on the immune status of human newborn infants.Ten surgical infants (age less than 6 months) requiring PN were studied in two consecutive phases: (A) after 31.1+/-6.0 days (mean +/- SEM) of PN with no enteral feeding (total PN); and (B) after 4.7+/-1.1 days from the addition of small volumes of enteral feeding to PN. Full blood count and liver function tests were not significantly different between phases A and B. A control group (n = 9) of infants receiving a normal enteral diet was also studied. Host bactericidal activity against coagulase-negative staphylococci (CNS) was measured by an in vitro whole blood model. Bacterial killing was measured after a 45-minute bacterial challenge using the Miles-Misra technique. Tumour necrosis factor-alpha (TNF-alpha) was measured by enzyme-linked immunosorbent assay (ELISA) after 2 hours of bacterial challenge.The lowest level of CNS killing (37.7+/-5.2%), was observed in patients receiving total PN. This increased significantly after the addition of small enteral feeds (52.0+/-4.6%, P.005) approaching the levels measured in controls (65.1+/-3.4%). TNF-alpha production was low during total PN (1467+/-297 pg/mL) and rose significantly after the addition of minimal enteral feeds (4,661+/-1,311 pg/mL, P.05). The increase in CNS killing after the addition of small enteral feeds in patients on PN was significantly correlated with the duration of enteral feeding (r = 0.8, P = .006).These results indicate that the introduction of small volumes of enteral feed improve the impaired killing of CNS and the abnormal cytokine response observed during total PN. This implies that stimulation of the gastrointestinal tract may modulate immune function in neonates and prevent bacterial infection.

The aim of this study was to review the cases 200 children and 40 adults who had cyst excision combined with hepaticoenterostomy (CEHE) for choledochal cyst, with particular emphasis on post-CEHE complications and their surgical management. Patients who had CEHE at the age of 15 years or less were defined as children, and those aged 16 years or older were defined as adults. The mean age when patients became initially symptomatic was 3 years in children and 26 years in adults. Eleven adults became symptomatic as children (< or = 15 years of age). The mean age of CEHE in children and adults was 4.2 years and 35 years, respectively. The time interval between the onset of initial symptoms and CEHE was significantly less in children than in adults (P < .0001). Of the 200 children, 176 had primary CEHE, and 24 had secondary CEHE converted from cystoenterostomy or other biliary surgery. Seventy children had intraoperative cyst endoscopy, which enabled us to examine the proximal intrahepatic bile ducts for stenosis and debris, and to wash out debris, protein plugs, and stones from the intrapancreatic ducts. Of the 40 adults, 22 had primary CEHE, 18 had secondary CEHE. The mean follow-up period was 10.9 years in children and 10.7 years in adults. The number of patients with post-CEHE complications in children and adults was 18 (9.0%) and 17 (42.5%), respectively. The post-CEHE complication rate in children was significantly lower than in adults (P < .0001). The 18 children had 25 post-CEHE complications such as cholangitis, intrahepatic bile duct stones, pancreatitis, stone formation in the intrapancreatic terminal choledochus or pancreatic duct, and bowel obstruction. Twenty-seven post-CEHE complications developed in the 17 adults including 2 cases of cholangiocarcinoma. There were no post-CEHE complications in the 70 children who had intraoperative cyst endoscopy. No stone formation was seen in the 145 children who had CEHE at the age of 5 years or less. Eight stone formations were seen in seven (12.7%) of the remaining 55 children aged over 5 years. Stones developed in seven (17.5%) adults. The incidence of post-CEHE stone formation in children aged 5 years or less was significantly lower than in other children and adults (P < .0001). Reoperation was required in 15 children: revision of hepaticoenterostomy in 4, percutaneous transhepatic cholangioscopic lithotomy (PTCSL) in 1, excision of intrapancreatic terminal choledochus in 2, endoscopic sphincterotomy of the papilla of Vater in 1, pancreaticojejunostomy in 1, and laparotomy for bowel obstruction in 6. Ten adults required reoperations: revision of hepaticoenterostomy in 2, PTCSL in 2, left hepatic lobectomy in 1, endoscopic sphincterotomy in 2, exploratory laparotomy in 2, and adhesiolysis in 1. The authors conclude that early diagnosis followed by CEHE is the treatment of choice for choledochal cyst, and intraoperative cyst endoscopy is recommended as a valuable adjunct to CEHE.

Rare b decay processes are analyzed in the multi-Higgs doublet model. Taking account of the constraint from the b → s γ process, the branching ratio and the forward-backward asymmetry of the final leptons for the b → sl+l− process are calculated. It is shown that the branching ratio can be a few times larger than the standard model prediction and the asymmetry can be significantly different from that in the standard model. Combining these observable quantities it is possible to determine complex coupling constants associated with the charged Higgs mixing matrix. The CP violating charge asymmetry in the b → sl+l− process and the branching ratio of the b → sν ν process are also calculated.

The concentration of endogenous adenosine in the cerebrospinal fluid increased 2–3-fold of the original level in the area of rat superior colliculus after the intraperitoneal administration of an adenosine deaminase inhibitor, EHNA (erythro-9-(2-hydroxy-3-nonyl)adenosine, 10 mg/kg). Potentials evoked in the superior colliculus by optic tract stimulation were also facilitated by 120–160% of their initial amplitudes. A selective A1 adenosine receptor antagonist, DPCPX (8-cyclopentyl-1,3-dipropylxanthine), failed to reduce such EHNA-induced facilitation. However, a selective A2A adenosine receptor antagonist, KF17837 (8(3,4-dimethoxystyryl)-1,3-dipropyl-7-methylxanthine) completely eliminated the facilitatory effects of EHNA. Northern blot analysis demonstrated abundant expression of A1 adenosine receptor mRNA in the superior colliculus. RT-PCR analysis was able to detect the concomitant expression of A2A adenosine receptor mRNA, but at levels lower than one-tenth of the striatal expression. In the superior colliculus, A2A adenosine receptors function predominantly on the facilitatory effects of adenosine, irrespective of the ubiquitous expression of A1 adenosine receptors.

Objective. The purpose of this study was to evaluate postoperative stability in prognathic patients with mandibular asymmetry who were treated with sagittal split ramus osteotomy of the mandible. Study design. Ten asymmetric (group I) and 11 symmetric (group II) patients were examined. An appliance for repositioning the proximal segment was applied, and the bony segments were fixed with titanium screws. Cephalograms were obtained preoperatively, 2 to 3 days postoperatively, and 3 and 6 months after surgery. Changes in the positions of the standard points were examined on lateral cephalograms, and changes in the widths of the gonion points were examined on posteroanterior cephalograms. Results. Statistical analysis revealed no significant difference between the two groups. In addition, there was no significant difference between the postoperative changes in the widths of the gonion points on the deviated and nondeviated sides in group I. Conclusions. This study suggests that application of an appliance for repositioning the proximal segment can minimize postoperative skeletal changes in patients with asymmetry.

Six aliphatic sulfates, kairomones released from a crustacean Daphnia pulex induce morphological changes of phytoplankton Scenedesmus gutwinskii at ppb (10 −9 g/mL) concentrations.

The effect of hypothermia on the tolerance of the cortex and brain stem to anoxic insult was investigated using slices from the hippocampus and superior colliculus of the guinea pig. The postsynaptic potential (population spikes) was recorded in the granule cell layer of the hippocampal slices after electrical stimulation to the perforant path. In the case of the superior collicular slices, the postsynaptic field potential was recorded in the superficial gray layer (SG) after stimulation to optic layer (OL). Perfusion medium deprived of oxygen and glucose completely blocked the electrical activity which subsequently recovered after reintroduction of oxygen and glucose. Monitoring the electrical activity, we studied the effect of temperature (37 degrees C, 35 degrees C, 33 degrees C and 30 degrees C) during deprivation of oxygen and glucose on the survival time of each slice. With mild hypothermia (35 degrees C) the survival time of slices from the superior colliculus was 15 min whereas that of hippocampal slices was 10 min. At 33 degrees C and 30 degrees C the hypothermia had a similar protective effect on the survival time in both slices from hippocampus and superior colliculus. These results suggest that there is a regional difference in the resistance of brain tissue to anoxia, and the brain stem is more resistant to anoxia than the cortex under mild hypothermic condition (35 degrees C).

Postsynaptic field potential was elicited in the central nucleus of the rat inferior colliculus after electrical stimulation to the lateral lemniscus. The inhibitory action of locally applied GABA on the potential was blocked by the systemic administration of picrotoxin, a GABAA antagonist (2.5 mg/kg, i.p.). After the administration of picrotoxin, the tetanic stimulation of 50 Hz for 20 s increased the amplitude of the field potential to over 120% of the original level in 10 min; this was maintained for 40 min, and formed the long-term potentiation (LTP). The tetanic stimulation alone, however, failed to enhance the amplitude. Thus, LTP was induced in the inferior colliculus only when GABAergic action was depressed.

The block of synaptic transmission and neural activity during deprivation of oxygen or glucose has been simply attributed to the lack of energy due to the disorder of energy production. To clarify the interrelation between neural activity and energy metabolism during hopoxia or glucose deprivation, we studied the changes in ATP levels and electrical events of pyramidal neurons in the CA3 region and [Ca2+]i mobilization of the dendritic and cellular region of CA3 area, using guinea pig hippocampal slices. The studies of field potentials and intracellular recording from the pyramidal cell of CA3 area during hypoxia or glucose deprivation revealed that the cessation of synaptic activity and the depolarization of resting potential occurred earlier during hypoxia than during glucose deprivation while the increase of [Ca2+]i was slow during hypoxia but rapid during glucose deprivation although the ATP level of CA3 area was maintained at its original level for 20 min during both conditions. When glucose was replaced by lactate, ATP concentration was not reduced but the electrical activity decayed and [Ca2+]i increased with the similar time course as observed during lack of glucose, only. These results suggest that different mechanisms underlie the block of synaptic transmission in the CA3 pyramidal neurons during hypoxia and glucose deprivation and that lactate cannot substitute for glucose in the maintenance of neural activity.

Purpose: The aim of this study was to review the outcome of a protocol the authors proposed for preventing Roux-en-Y hepatico-jejunostomy (RYHJ) related complications. Methods: In 1986 the authors adopted the following protocol for improving RYHJ to minimize risks for RY-related complications: (1) end-to-end anastomosis if possible; (2) if end-to-side anastomosis is unavoidable, the common hepatic duct should be anastomosed as close as possible to the closed end of the blind pouch (BP); (3) careful selection of the vascular supply to the RY jejunal limb; (4) length of the RY jejunal limb should not be predetermined, but individualized; (5) approximate the native jejunum to the RY limb. The authors reviewed 92 children who had surgery for CC (mean age at surgery, 4.1 years) at our institution between 1986 and 2002 to assess the effectiveness of their recommendations. Results: After the adoption of the authors' recommendations for RYHJ, they have experienced no RYHJ-related complications after a mean follow-up period of 7.6 years (range, 4 months to 16 years). Conclusions: RYHJ in children is different from that in adults, because the RY limb or BP can grow and elongate as the child grows. The authors' recommendations appear to have successfully prevented RY-related complications up to the time of this review, and they highly recommend their use.

The authors present 3 cases of proximal hypospadias associated with bilateral undescended testes (UDT) in which the gubernaculum was used to reinforce the neourethra to prevent urethrocutaneous fistula. This is the first report of the gubernaculum being used to reinforce the neourethra. The technique is simple and should be applicable to any hypospadias patient with concomitant UDT, especially in severe hypospadias. Good outcome is likely because of the excellent blood supply of the gubernaculum.

The postsynaptic field potential (population spike; PS) was recorded in the CA1 area of guinea pig hippocampal slices in response to electrical stimulation of Schaffer's collateral. After tetanic stimulation (100 Hz for 1 s) to Schaffer's collateral, the PS amplitude increased to 127.9 ± 7.7% (mean ± S.E.M.) of the original level at 20 min and 140.1 ± 7.7% at 60 min, and formed long-term potentiation (LTP). After application of 10 nM propentofylline, a synthetic xanthine derivative, which did not enhance the amplitude of the PS evoked by the test stimulus, the tetanic stimulation increased the amplitude to 160.3 ± 3.8% at 20 min and 173.3 ± 4.3% at 60 min. Thus, propentofylline enhances the formation of LTP in hippocampal slices.

Adenosine has excitatory actions on neurotransmission in the superior colliculus. To investigate whether adenosine A 1 or A 2 receptors are involved in mediating these excitatory actions, the effect of A 1 and A 2 receptor agonists and antagonists on the evoked postsynaptic potentials (PSP) in the superficial grey layer were tested using slices of the superior colliculus. Application of both A 1 agonists, such as CHA, R-PIA, and the A 2 agonist, CGS-21680 increased the amplitude of the PSP. The increase in PSP amplitude occured gradually over 20–30 min after application of these adenosine agonists. Application of the A 1 antagonist 8-CPT, and the A 2 antagonists, DMPX and CGS-15943, increased the amplitude of the PSP and could not antagonize the excitatory effect of adenosine. These results suggest that the mechanism of the excitatory effect of adenosine cannot be explained by the classical concept of A 1 and A 2 adenosine receptor subtypes which were identified by their effect on adenylate cyclase activity.

To confirm the effect of gangliosides on the facilitation of the induction of long-term potentiation (LTP), slices of hippocampus and superior colliculus from guinea pig were prepared. One group of slices was incubated in the standard medium containing gangliosides (GM1, GD1a, or a mixture of gangliosides from bovine brain, each at a concentration of 70 μM) for 2 h. The other group of slices was incubated in the standard medium only. In both groups of slices, tetanic stimulation induced LTP in a similar manner. In low Ca2+ (1 mM) medium, LTP was not induced in either group of slices. Thus, the present experiments could not confirm previous reports indicating that exogenously applied gangliosides facilitate the induction of LTP.

A constraint from $b\rightarrow s\gamma$ process to the minimal supersymmetric standard model is derived in the light stop region where the coupling between the lighter stop and the $Z^0$ boson vanishes due to the left-right mixing of the stop states. It is pointed out that although some region in the parameter space is excluded from this process there remains a large parameter space where the amplitude of the $b\rightarrow s\gamma$ is suppressed due to partial cancellation between different diagrams. Stop as light as 20 GeV is still viable from the $b\rightarrow s\gamma$ constraint.

To investigate the effect of toluene and its derivatives on neural activity, postsynaptic field potential (population spike, PS) of granule cells as well as antidromic potential (AP) and presynaptic fiber potential (FP) (perforant path) were recorded in the guinea pig hippocampal slices. Toluene at the concentration of 0.2 ng/ml to 20 micrograms/ml in the perfusion medium increased the amplitude of PS to 109-150%. Toluene also increased the amplitude of FP and AP, although the most remarkable enhancement was observed in the PS. However, toluene at the concentrations over 1000 micrograms/ml completely depressed the PS, whereas it increased the amplitude of AP to 130% of the original level. These results indicate that toluene has excitatory and inhibitory biphasic effects on neurotransmission in the hippocampal slices according to concentration applied.

To investigate the involvement of N-methyl-D-aspartate (NMDA) receptor, protein kinase C (PKC) and calmodulin on long-term potentiation (LTP) formation in the superior colliculus (SC), the effects of an NMDA receptor antagonist (D-APV), PKC inhibitors (H-7, K-252a, K-252b, polymyxin B), a protein kinase A (PKA) inhibitor (H-8) and a calcium/calmodulin-dependent kinase inhibitor (calmidazolium) on LTP formation were studied in guinea pig SC slices. APV (100 microM) masked the expression of LTP by tetanic stimulation, but the LTP once formed was not influenced by application of APV. LTP was blocked by application of H-7 (100 microM), but LTP reappeared 20 min after removal of H-7 from the perfusion medium without further tetanic stimulation. On the other hand, established LTP was also inhibited by application of H-7 even 90 min after the tetanic stimulation. Application of K-252a (500 nM) inhibited LTP formation, but K-252b (500 nM) had no inhibitory effect on LTP formation since K-252b, unlike K-252a, cannot permeate the cell membrane. Tetanic stimulation was applied 20 min after application of polymyxin B (1 microM) to the medium but it could not induce LTP, while established LTP was not influenced by the drug. Application of calmidazolium (50 microM) inhibited LTP formation, but had no inhibitory effect on LTP once formed. These results suggest that both the NMDA receptor and calmodulin system are involved in the induction of LTP after tetanic stimulation. This leads to PKC activation which maintains the LTP.

The postsynaptic field potential (population spike; PS) was recorded from the granule cell layer of guinea pig hippocampal slices after electrical stimulation of the perforant path. Propentofylline, a xanthine derivative, enhanced the amplitude of PS to 120–150% of the original level at a concentration range of 100 nM to 1 mM. Theophylline at concentrations over 10 μM increased the PS amplitude to 200% of the original amplitude. Simultaneous application of 1-(5-isoquin-olinesulfonyl)-2-methylpiperazine dihydrochloride (H-7; 100 μM), a protein kinase C (PKC) inhibitor, significantly blocked the excitatory effect of propentofylline, but it failed to counteract the excitatory effect of theophylline. These results indicate that the excitatory effect of propentofylline is mediated by a metabolic process involving PKC and that the protective effect of propentofylline on neuronal damage caused by hypoxia is not due to the inhibition of synaptic transmission.

The upper bound of the lightest neutral Higgs boson mass is calculated in a supersymmetric standard model with extra matter multiplets. Assuming that all dimensionless coupling constants do not blow up below the grand unification scale, we show that the upper bound is about 175–180 GeV when the top quark mass is less than 200 GeV and the stop mass is 1 TeV. Also, in a model with a gauge singlet, the upper bound is shown to be about 150 GeV.

Adenosine has dose-dependent biphasic excitatory and inhibitory effects on neurotransmission in the hippocampus. The mechanism of the excitatory action is not known although that of the inhibitory action has been well analyzed. Here we report on the mechanism of excitatory action of adenosine, using hippocampal slices. Studies of intracellular recordings of CA3 pyramidal neurons showed that the amplitude of EPSP was dramatically enhanced by application of adenosine at low concentration (0.1 μM) without changing resting membrane potentials, membrane conductance or the threshold for spike generation by injecting current pulses. On the other hand, the presence of adenosine at a concentration of 0.1 μM during electrical stimulation to the slices increased 1.7 times the release of glutamate, an excitatory neurotransmitter in the hippocampus. These results indicate that the excitatory action of adenosine at low doses is due to the increase of transmitter release.

The role of ketone body on neural activity and energy metabolism in the brain was investigated. Guinea pig hippocampal slices were prepared, and postsynaptic field potentials (PSPs) were recorded in the granular cell layer of the dentate gyrus. ATP and phosphocreatine (CrP) in the tissue slice were measured after 60 and 120 min incubation in standard medium (1) with 10 mM glucose, (2) with 10 mM glucose plus 20 mM d,l -3-hydroxybutyrate (3-OHBA), (3) without glucose, (4) with 20 mM 3-OHBA instead of 10 mM glucose. In (3), both ATP and CrP in the slice decreased to 40–45% of the original level after 120 min. On the other hand, the ATP level was well maintained even 120 min after incubation in (1), (2) and (4), whereas the CrP level decreased to 62% in (4). Further, slices were incubated in (3) and (4) for 30, 60, and 120 min, and the presence of PSP was tested. In (3), the number of slices from which PSPs could be recorded decreased, and after 120 min PSPs were hardly observed. In (4), that number decreased gradually, and only 45% of the slices showed PSPs after 120 min. These results indicate that 3-OHBA can be a substrate to produce high-energy phosphate but cannot maintain the neural activity as glucose does.

We calculate a mass of the lightest Higgs boson in the minimal supersymmetric standard model by solving one-loop renormalization-group equations. In the range mt = 150–200 GeV and for a supersymmetry breaking scale mSUSY = 1–100 TeV the mass mH0 varies from 70 GeV to 190 GeV. A possibility to probe the supersymmetry breaking scale is also discussed.

Superior colliculus (SC) slices were prepared from guinea pig. Electrical stimulation was applied to the optic layer (OL) of the SC slices and the postsynaptic potential (PSP) was evoked in the superficial grey layer (SGL) of the SC. Tetanic stimulation to the OL evoked long-term potentiation (LTP) in the PSP. To investigate the involvement of the protein kinase C (PKC) system on the LTP formation in the SC, the effects of PKC activator (phorbol ester) and PKC inhibitors (polymyxin B, melittin and H-7) on the LTP formation have been studied. Application of phorbol ester to the medium at concentrations between 10 −8 and 10 −10 M increased the amplitude of the PSP. On the other hand, the presence of phorbol ester at a concentration of 10 −6 M increased the glutamate release from the SGL slices. Tetanic stimulation which could not induce LTP by itself could elicit LTP during application of phorbol esters at the low concentration (3 × 10 −12 M). PKC inhibitors such as polymyxin B (10 −7 M), melittin (10 −8 M) and H-7 (10 −4 M) prevented LTP formation. When H-7 was applied once after LTP was formed, the enhanced PSP reduced to the original level. These results strongly indicate the involvement of PKC system on the LTP formation in the SC slices.

Postsynaptic potentials (PSPs) were recorded from the granular cell layer of guinea pig hippocampal slices. Application of adenosine at a concentration of more than 10 microM in the incubation medium depressed the amplitude of the PSP, but adenosine at a concentration of 10 nM to 1 microM enhanced the amplitude of the PSP. The dose-response curve of the effect of adenosine showed an excitatory and inhibitory biphasic pattern. Adenosine analogues such as adenosine triphosphate (ATP), adenosine diphosphate (ADP) and nicotinamide adenine dinucleotide (NAD) showed similar biphasic effects, however beta-gamma-methyleneadenosinetriphosphate (beta-gamma-ATP), 5'-N-ethylcarboxamidoadenosine (NECA). N6-cyclohexyladenosine (CHA) and N6-R-phenylisopropyladenosine (RPIA) revealed only inhibitory effects.

A path-integral formulation is given for a system with non-abelian conserved charge. For a quantum mechanical model and a field theory, saddle-point equations for the semi-classical approximation are derived taking account of boundary conditions. Applying this formalism to a scalar theory with non-abelian symmetry coupled with gravity, we show that there exist wormhole solutions with non-abelian charge.

Purinoceptor agonists produced potassium currents with the order of potency: ATP>adenosine=ADP=AMP> β , γ -methylene ATP, while a small response or no response was induced by 2-methylthio ATP, UTP, or α , β -methylene ATP. The response induced by β , γ -methylene ATP was completely inhibited in the presence of α , β -methylene ATP, suggesting that the relevant receptor for these agonists was a P 3 purinoceptor. ATP induced currents with a latency of 24 s and the currents were not induced in defolliculated oocytes. The currents were not affected by either the G i/o -protein inhibitor, pertussis toxin (PTX), or the selective cAMP-dependent protein kinase inhibitor, H-89, or the phospholipase C (PLC) inhibitor, neomycin, or the phospholipase A 2 (PLA 2 ) inhibitor, 4-bromophenacyl bromide. The currents were enhanced by the selective protein kinase C (PKC) inhibitor, GF109203X, but otherwise, they were reduced by the potent PKC activator, 12- O -tetradecanoylphorbol-13-acetate. The results of the present study suggest that a P 3 purinoceptor in the follicle cell layer of oocytes is involved in activation of potassium channels and that the evoked currents are regulated by PLC/PLA 2 -independent PKC activation.

1. (1) We have bee successful in establishing a conversion formula that can establish the random vibration test conditions based on the measured values of the peak accumulated. 2. (2)We learned that, not only the main components of engine vibrations, but other components are also important in the phenomena of contact wear, from the fact that the evaluation tests based on random vibrations could reproduce contact wear far better that the sime wave sweep test.

Superior colliculus (SC) slices were prepared from guinea pigs and postsynaptic potentials (PSPs) were recorded in the superficial grey layer of the SC after electrical stimulation to the optic layer (OL). Tetanic stimulation of 50 Hz frequency and 20 s duration to the OL induced long-term potentiation (LTP) in the PSP increasing the amplitude to 140% of the original level in 30 min. Tetanic stimulation failed to induce LTP after application of γ-aminobutyric acid (GABA) (300 μM, 1 or 3 mM) to the perfusion medium. On the other hand, tetanic stimulation to the OL after application of bicuculline methiodide (1 μM), a GABA A receptor antagonist, facilitated the formation of LTP. These results indicate that GABA modulates the formation of LTP in the SC.