Combined treatment using CEA and CAS for carotid arterial stenosis.

In this study we report our surgical results of CAS and CEA for carotid stenosis and suggest an appropriate treatment strategy for patients with high risks such as bilateral carotid stenosis or medical risk factors. From January 2001 to December 2005 we surgically treated 182 patients with carotid stenosis. Seventy-nine lesions were treated by CEA and 145 by CAS, respectively. Although CEA was considered the first choice for severe carotid stenosis, CAS was chosen for treatment when CEA was considered a higher risk for patients. Stenosis of carotid arteries was relieved in all cases after CEA or CAS. Surgical mortality of CEA was 1.1% (1/94). Surgical mortality of CAS was 0.7% (1/145). Carotid stenotic lesions can be treated with comparably low morbidity and mortality rates using CEA or/and CAS considering each characteristic of carotid stenosis of patients even with medically high risk or bilateral carotid stenosis.

Heat-moisture treatment of high-amylose corn starch increases dietary fiber content and lowers plasma cholesterol in ovariectomized rats.

The effect of dietary high-amylose corn starch (HACS) of varying dietary fiber (DF) content on plasma cholesterol was examined in ovariectomized (OVX) rats. Gelatinized normal corn starch (G-CS) was used as a reference. OVX rats were fed a fiber-free purified diet containing G-CS, HACS, gelatinized high-amylose corn starch (G-HACS), or heat-moisture treated HACS (HM-HACS) at 400 g starch/kg diet for 21 d. The DF content of G-CS, HACS, G-HACS, and HM-HACS measured by the AOAC method was 0.1, 19.3, 2.4, and 64.5 g/100 g, respectively. The dry weight of cecal contents, cecal wall weight, the amount of short chain fatty acids in cecal contents, the amount of bile acids in small intestinal contents, and fecal excretion of neutral sterols increased logarithmically with increasing DF, while total plasma cholesterol concentration decreased. On the other hand, hepatic CYP7A1 activity, fecal dry weight, and fecal excretion of bile acids increased linearly with increasing DF, while body weight gain decreased. The hypocholesterolemic effect of HACS in OVX-rats appeared to be more effective by heat-moisture treatment.

Inflammatory reaction following cataract surgery and implantation of acrylic intraocular lens in rabbits with endotoxin-induced uveitis.

PURPOSE: To investigate whether inflammatory responses are more severe in uveitic eyes than nonuveitic eyes when acrylic intraocular lens (IOL) is implanted after cataract surgery. METHODS: Clear lens removal (phacoemulsification and aspiration) was conducted and the hydrophobic acrylic IOL (AR40e, AMO) was implanted in adult albino rabbits. Just after the operation, rabbits were divided into two groups. One group (nine rabbits) received intravitreal injection of lipopolysaccharide (LPS, 200 ng/10 microl) into both eyes to induce endotoxin-induced uveitis (EIU) and the other group (nine rabbits) received intravitreal injection of phosphate-buffered saline (PBS, 10 microl) into both eyes as the control. Aqueous humour (AH) and IOLs were harvested 1, 3 , and 7 days after the intravitreal injection. The infiltrating cell number in AH was counted and the protein concentration of AH was measured. IOLs were evaluated morphologically. RESULTS: At 1 day after intravitreal injection, both the infiltrating cell number in AH and protein concentration of AH were significantly higher in the LPS-injected group than in the PBS-injected group. Similarly, more inflammatory cells attached to the surfaces of the IOLs in the LPS-injected group. However, 7 days later, inflammatory reactions subsided and no clear differences in any of the parameters examined were observed between the two groups. CONCLUSIONS: At 7 days after the operation, inflammatory reactions in eyes implanted with the hydrophobic acrylic IOLs were similar in uveitic eyes and nonuveitic eyes. The data suggest that the hydrophobic acrylic IOLs may be suitable for patients with uveitis.

Surgical treatment for bilateral carotid arterial stenosis.

Carotid endarterectomy (CEA) is a beneficial procedure for patients with high-grade carotid stenosis. However, patients with bilateral carotid stenosis have a higher surgical risk during CEA. Since the introduction of carotid stenting (CAS) may decrease some of the surgical complications of CEA, a combined treatment using CEA and CAS may be favorable for patients with bilateral carotid stenosis. We analyzed the safety and efficacy of this treatment strategy. Eighteen patients with bilateral carotid stenosis were treated from January 2000. Bilateral CEA was performed on the first two patients, CAS then CEA of contra-lateral symptomatic side in 13 patients, and bilateral CAS in three patients. There were no perioperative neurological complications or strokes during the follow-up period (mean 17 months). The combined treatment of CAS and CEA was a safe and effective strategy for bilateral carotid stenosis.

Stenting for vertebrobasilar artery stenosis.

We report our experience with stenting for symptomatic vertebrobasilar artery stenosis. One hundred and sixteen patients with vertebrobasilar artery stenosis (101 vertebral ostial stenosis, 15 intracranial vertebrobasilar artery stenosis) were treated with stenting. Indication criteria of treatment were 1) symptomatic lesion, 2) angiographical stenosis more than 60%. Under local anesthesia, pre-dilatation was first performed, then stents were placed to the lesion. Successful dilatation was obtained in 115 cases. The stenosis rate reduced to 2% post-stenting in ostial lesions and 16% in intracranial lesions. Transient neurological complications developed in 2 patients. Follow-up angiographies more than 6 months after stenting were performed in 94 patients with ostial lesions and all patients with intracranial lesions. Of these, 8 patients (9.5%) with ostial lesions and 4 patients (27%) with intracranial lesions developed restenosis. All patients with restenosis were treated successfully with PTA (percutaneous transluminal angioplasty). During the follow-up period, 3 patients developed recurrence of VBI (vertebro-basilar insufficiency) symptoms due to restenosis. One patient developed brain stem infarction due to in-stent occlusion 8 months after stenting. Conclusion. Stenting for vertebrobasilar artery stenoses is feasible and safe. Prevention of restenosis, especially in intracranial arteries, is the next problem to be solved.

[Localization of the pyramidal tract in the internal capsule: relationship between CT classification of thalamic hemorrhage and motor weakness].

To better understand the pyramidal tract of the internal capsule, we evaluated the relationship between the localization of thalamic hemorrhage and motor weakness. On an axial CT scan at the level of the pineal body, two lines were drawn as follows: line-a between the lateral edge of the anterior horn and the lateral edge of the trigone, line-b vertical to the sagittal line and passing the midpoint of the third ventricle. The location of the hematoma was classified into three types according to localization of the center of the hematoma and lateral extension beyond line-a as follows: type A (anterior), type P (posterior) and type PL (postero-lateral). Discrepancy of motor weakness between upper extremities and lower extremities was higher in patients with hematoma of type P and type PL (p < 0.05) than in those with hematoma of type A. Improvement of motor weakness on discharge was higher in patients with type P (p < 0.01) than in those with type A. We concluded that most of the pyramidal tract fibers were located in the third quarter of the posterior limb of the internal capsule but a small number of pyramidal tract fibers were located in the anterior two-thirds of it. A greater number of cortico-spinal fibers to the upper extremities than to the lower extremities occupy the third quarter of the posterior limb of the internal capsule.

Enzymatic synthesis of novel fructosyl and oligofructosyl trehaloses by Aspergillus sydowi beta-fructofuranosidase.

An intracellular beta-D-fructofuranosidase produced by Aspergillus sydowi IAM 2544 was purified by Q-Sepharose and Alkyl-Sepharose chromatographies. The molecular mass was 50 kDa by SDS-PAGE analysis. The optimum pH and temperature of sucrose hydrolyzing activity of the enzyme were 5.5 and 75 degrees C, respectively, but those of fructosyl transferase activity were 5.2 and 55 degrees C, respectively. The enzyme efficiently transferred the fructose residue of sucrose as a donor to trehalose as an acceptor. And the amount of fructosyl and oligofructosyl trehaloses produced was changed by the molar ratio of trehalose as an acceptor to sucrose as a donor used. The most efficient production of the transferred products was achieved at the reaction conditions in the range of molar ratios of 1:1 to 3:1 (trehalose:sucrose). The chemical structures of these new kinds of resulting series of fructosyl and oligofructosyl trehaloses produced were identified as O-beta-D-Fru-(2-->6)-alpha-D-Glc-(1-->1)-alpha-D-glucopyranoside, O-beta-D-Fru-(2-->6)-alpha-D-Glc-(1-->1)-alpha-D-glucopyranoside, and O-beta-D-Fru-(2-->1)-O-beta-D-Fru-(2-->1)-O-beta-D-Fru-(2-->6)-alpha-D-G lc- (1-->1)-alpha-D-glucopyranoside. These results indicate that beta-fructofuranosidase from Aspergillus sydowi specifically transferred the fructose residue of sucrose to the C6-OH position of the glucose residue of trehalose at the early stage of the reaction, following the elongation of the fructose residue by the transfructosylation of the enzyme to form oligofructosyl trehalose of a longer fructose chain.

Usefulness of the pulse oximeter as a respiratory monitor during intravenous sedation.

During intravenous sedation, the pulse oximeter was applied as a respiratory monitor to 17 patients (Physical status classification of the American Society of Anesthesiologists, Class I-II) who were to have oral surgical operations, and the changes in arterial saturation of oxygen (SaO2) was observed consecutively. SaO2 dropped after administration of sedative agents in each case; there was some individual variation. Respiratory depression during sedation was evaluated from arterial blood gas analysis. The reduction in SaO2 caused by surgical manipulations was also noted. Furthermore, arterial partial pressures of oxygen (PaO2) and saturation calculated from PaO2 (SAT) measured from blood gas analysis were compared with SaO2 measured by the pulse oximeter. Both PaO2 and SAT correlated well with SaO2. The differences between SAT and SaO2 exceeded the range of error (+/- 2%) in many cases after the administration of sedative agents. These results suggest that the pulse oximeter is useful as a respiratory monitor during oral surgery. However, the pulse oximeter gives incorrect SaO2 readings in the presence of abnormal hemoglobin due to medication with nitrites or smoking habit.

Continuous production of maltotetraose using a dual immobilized enzyme system of maltotetraose-forming amylase and pullulanase.

In order to produce a product with a high content of maltotetraose, dual-enzyme systems composed of immobilized maltotetraose-forming amylase (G(4)-forming amylase) and pullulanase were studied. The thermostability of individually immobilized enzymes was examined in continuous operation; studies revealed that the enzyme immobilized on "Chitopearl" was much more stable than that immobilized on Diaion HP-50. The effects of operating conditions on the stability of G(4) forming amylase immobilized on "Chitopearl" were examined to confirm that the apparent half-life data could be arranged using the immobilized enzyme stability factor, f(s). As for the dual immobilized enzyme system, six methods of usage were considered, with five yielding a 7-10% (w/w) higher content of maltotetraose product than the single-enzyme system. The effects of operating conditions on the maltotetraose production reaction were examined to confirm that the maltotetraose content of the products could be analyzed using the specific space velocity,SSV. In dual immobilized enzyme systems, pullulanase immobilized on the same carrier as the G(4)-forming amylase was found to be more stable than pullulanase immobilized on separate carriers. The effectiveness of using immobilized pullulanase along with the G(4)-forming amylase was confirmed from constant-conversion operations in which the maltotetraose content in the product was kept at 50% (w/w) in laboratory-scale experimentation.

Enzymatic synthesis of p-nitrophenyl alpha-maltoheptaoside by transglycosylation of maltohexaose-forming amylase.

An extracellular maltohexaose-forming amylase [EC 3.2.1.98] from Klebsiella pneumoniae mutant is a normal hydrolytic enzyme that hydrolyzes short-chain amylose (DP = 23) to give about 40% maltohexaose. Transglycosylation from maltoheptaose to the 4-position of p-nitrophenyl alpha-glucoside was efficiently induced through the use of maltohexaose-forming amylase in an aqueous methanol solution. The enzyme specifically produced p-nitrophenyl alpha-maltoheptaoside (13% of the p-nitrophenyl alpha-glucoside) from maltoheptaose as a donor and p-nitrophenyl alpha-glucoside as an acceptor. The yield of p-nitrophenyl alpha-maltoheptaoside depended on the concentration of methanol solvent, the pH, and temperature. Furthermore, the use of the aqueous methanol system in the reaction not only improved the solubility of p-nitrophenyl alpha-glucoside but also greatly increased the formation of p-nitrophenyl alpha-maltoheptaoside, which is a useful substrate for assay of human amylase in serum and urine.

Stability of immobilized maltotetraose-forming amylase from Pseudomonas stutzeri.

The stability of immobilized maltotetraose (G(4))-forming amylase (1,4-alpha-D-glucan maltoteraohydrolase, EC 3.2.1.60) from Pseudomonas stutzeri was investigated in both batch and continuous processes. The inactivation process of the immobilized enzyme seemed to obey first-order kinetics, and the immobilized enzyme became more stable when coexisting with 20-30 wt % substrate and calcium ions. From intensive studies on the operational stability in the continuous process, the apparent half-life of G(4) productivity in a constant-flow system was mainly affected by the reaction temperature, substrate concentration, and initial immobilized enzyme activity. A new factor, immobilized enzyme stability factor f(s), was proposed to evaluate the half-life of the immobilized enzyme system.

Continuous production of maltotetraose using immobilized Pseudomonas stutzeri amylase.

A continuous production process of maltotetraose was investigated by using immobilized maltotetraose (G(4))- forming amylase (1,4-alpha-D-glucan maltotetraohydrolase, EC3.2.1.60) from Pseudomonas stutzeri adsorbed on a macroporous hydrophobic resin. The maximum reaction rate was obtained at 55 degrees C and the activation energy of hydrolysis by immobilized G(4)-forming amylase was calculated to be 8.45 kcal/mol. The maltotetraose yield was greatly influenced by the flow rate of substrate solution, its concentration, and the immobilized enzyme activity. The newly defined factor "specific space velocity" was successfully introduced to normalize the operating parameters. Using this factor, the immobilized enzyme reactor then can be simulated and the operating dynamics can be determined.

Immobilization of the exo-maltohexaohydrolase by the irradiation method.

Exomaltohexaohydrolase (E.C.3.2.1.98) was immobilized by radiocopolymerization of some synthetic monomers which were mixed in various combinations. Irradiation was carried out while the mixture of monomers and enzymes was frozen in petroleum ether-dry-ice bath. Recovery of the immobilized enzyme was 44-75%.The optimum pH of the enzyme slightly shifted to the acidic side. The pH stability was improved remarkably by immobilization. The enzyme was stable retaining more than 90% of its original activity in the range pH 4-11. The optimum reaction temperature of the enzyme increased about 2 degrees C. Heat stability was also improved by immobilization, and that the enzyme retained about 40% of its original activity after treatment at 75 degrees C for 15 min. The immobilized enzyme was stable to the repeated use of 20 cycles. The K(m) value of the enzyme for short-chain amylose was almost the same as that of native enzyme. When soluble starch was used as the substrate, the K(m), value of the enzyme was three times as large as that of native enzyme. Effects of various metal ions and inhibitors on the immobilized enzyme were also studied compared to the native enzyme.