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Synthesis and self-assembly of a mercaptoundecaneamide derivative having a terminus of 1,4-hydroquinone (QT) are described. Electrochemical measurements on the QT-modified Au electrode revealed that the alkanethiol compound undergoes self-assembly to exhibit specific electrochemical activity originates from the reversible quinone/hydroquinone redox reaction at the terminus. We have achieved to obtain the electrochemical active surface coverage (0.11 nmol cm −2 ), formal potential (+246 mV, pH 3, Ag/AgCl) that changes pH-dependently (58 mV per pH) and also a set of the electron transfer reaction parameters, all of which were consistent with those of the previously reported structural isomer, catechol-terminated mercaptoundecaneamide (CT). Contrastingly, we found that these alkanethiol monolayers give marked contrast in an elecrocatalysis application: the CT-monolayer electrodes showed electrocatalytic capability in oxidation of NADH solution species while the QT-monolayer electrodes did not at all. By comparing some results of theoretical approach, we have attributed the surface selectivity to the spatiality of particular molecular orbital in the catalysis molecule. This observation should be important as an example of spatiality–reactivity relationships in a molecular design of chemically modified electrode.

Large-ring cyclodextrins (LR-CDs) composed of more than 9 d-glucose units are not well studied. In this study, LR-CDs composed of 36, 37, 38 and 39 d-glucose units (CD36∼ ∼CD39) were isolated and purified from a LR-CD mixture, and their physicochemical properties including aqueous solubility, surface tension, specific rotation and acid-catalyzed hydrolysis rate were elucidated. The aqueous solubilities of CD36∼ ∼CD39 were greater than those of α-, β-, γ-CD, CD9, CD10, CD14 and CD26. CD36∼ ∼CD39 did not show any surface activity. The acid-catalyzed hydrolysis of CD36∼ ∼CD39 was a little faster than that of other LR-CDs (CD9∼ ∼CD35). There was no marked difference in specific rotation or the acid-catalyzed hydrolysis rate among CD36∼ ∼CD39. Furthermore, we compared these findings with the physicochemical properties of α-, β-, γ-CD and other LR-CDs (CD9∼ ∼CD35).

Proximal femoral derotational osteotomy was performed bilaterally on 10 children who had spastic diplegia with internal rotation gait, in combination with simultaneous multiple operations for soft tissue contractures of the lower extremities.The degree of derotation was determined intraoperatively and about 10° internal rotation at the hip was expected after surgery. Soft tissue release was followed about 4 weeks after osteotomy.The mean age at operation was 6 (4-10) years.The average follow-up was 1 year and 11 months (4 months-5 years).The average femoral anteversion was preoperatively 62° (55-70°) and improved to 24° (0-50°) in the final examination.The average derotation measured intraoperatively was 56° (45°-70°) and the average internal rotation at the hip reduced from 77° (55°-105°) to 32° (15°-50°) with a similar increase in external rotation after operation. All patients except one showed improvement of the internal rotation gait.One showed a mild recurrence of the unilateral internal rotation gait.The average time to regain preoperative ambulatory status was 5.3 (3.5-9) months. No children got worse in terms of walking ability.We realized that derotational osteotomy is necessary for correcting internal rotation gait in addition to soft tissue release.

Lanthanum chromites ((La, A) (Cr, M) O3; A=Ca, Sr, M=Co, Ni, Cu, Zn) were synthesized and characterized from their density, thermal expansion coefficient and chemical stability. Cobalt doped lanthanum calcium chromites with La-site/Cr-site ratio>1 were densely sintered at 1400°C, and it is possible to adjust the thermal expansion coefficient to that of YSZ by controlling the amount of dopants. Lanthanum strontium chromites with La-site/Cr-site ratio=1 were not densely sintered at lower temperature than Ca-doped, but kept enough strength after reduction treatment. difference of strength change after the reduction treatment between Sr-doped and Ca-doped ones is related to the difference in lattice expansion after the treatment.

A 70-year-old female presented with an 8 month history of upper back pain. She had initially been treated with steroids without any improvement. After the steroids were discontinued, she developed gait disturbance and dysesthesia in her hands and legs. On admission, neurological examination revealed tetraparesis with pyramidal signs in both extremities. Myelogram and spinal CT showed narrowing of the subarachnoid spaces from C7 to T3, from T7 to T8 and from T10 to T11. A gadolinium-DTPA enhanced T1-weighted magnetic resonance imaging revealed marked enhancement of the dura in areas consistent with abnormalities shown by the myelogram. Laminoplasty of C6 to T2 and laminectomy of T6 to T8 were performed. Markedly thickened dura compressing the cord was noted, then this was partially excised and replaced by a patch graft. The pathological diagnosis was a nonspecific chronic inflammation. After surgery, the patient's symptoms disappeared. However with tapering off of steroids, her upper back pain reappeared. Therefore steroids were given orally on alternate days.It is stressed that MRI with enhancement is the best method for diagnosis of hypertrophic pachymeningitis and removal of the affected dura and administration of steroids are suitable treatments for this disorder.

Osteopetrosis associated with renal tubular acidosis and cerebral calcification was established as an autosomal recessive inheritant syndrome, caused by a deficiency of carbonic anhydrase II (CA II) in 1983. Only 3 cases have been reported in Japan.We describe a family with this syndrome. Proband is a 31 year old female, who presented with pathological fracture of the femoral, tibial and fibullar shafts, renal tubular acidosis and cerebral calcification. She was treated with intramedullary nailing and long leg cast followed by PTB brace. Bone biopsy was done from the iliac wing. Pathology showed irregular thickening of trabecular bone and unresorbed persistent calcified cartilage. Only a few osteoclast and fibroblast cells were found, suggesting poor bone remodeling.Her two sisters are short and the elder one is affected with mild mental retardation. Both have osteopetrosis, renal tubular acidosis, cerebral calcification, and a history of long bone fracture. Her parents are not affected and not consanguineous. CA II activity was measured from erythrocyte hemolysates in all of the family. CA II activities from the mother, father, and three sisters were 57%, 40%, 13%, 15%, and 18% each, compared to the normal control. We consider these three sisters are homozygotes of CA II deficency and their parents heterozygotes.

A long-chain, dialkyl disulfide having a terminal dinitrophenyl (DNP) group was newly synthesized for modification of a surface of gold with chemisorbed, self-assembled organic monolayers. The resulting monolayer was characterized by infrared spectroscopy of reflection absorption spectroscopy mode, by cyclic voltammetric measurement and by electrical impedance measurement. Coupled with impedance measurements, a possible application of the modified electrode system to impedimetric immunosensors was demonstrated. The sensor gave electrical response to anti-DNP antibody at 10-103ng cm-3 concentration.

Synthesis of a mercaptoundecaneamide derivative having a terminus of catechol is described. FT-IR spectroscopic characterization showed that the new molecular entry simply undergoes molecular self-assembly on Au substrate surfaces promoting intra- and intermolecular hydrogen bonds to form well-packed monolayers. Cyclic voltammetric (CV) measurements on the monolayer-modified Au electrode revealed that the surface adlayer possesses specific electrochemical activity due to the reversible catechol/o-quinone redox reaction having characteristics of a surface process and also pH-dependence in its formal potential (59 mV per pH). Detailed analysis of CVs gave fundamental electrochemical parameters including the electroactive surface coverage (0.20–0.24 nmol cm−2), the transfer coefficients (0.24 in oxidation and 0.81 in reduction), and also the electron transfer rate constant (1.10–2.76 s−1). These data were almost consistent to those seen in literature. We have also found that the catechol monolayer modified electrode exhibits an electrocatalytic function in NADH oxidation. That is, the faradaic current appeared reinforcingly at around the same potential where catechol function is oxidized in the monolayer and increased with an increase in the NADH concentration from 1 to 5 mM, and then reached to a plateau indicating a catalyzed reaction pathway. Detailed analyses revealed that the present system could be characterized by its weak stability of the intermediate compound formed and prompt reaction rate compared with the previously reported chemically modified electrode (CME) systems. We think this type of achievement should be important for the basics of biosensors that rely on dehydrogenase enzymes.

We have developed fabrication process for planar SOFC fabricated with cofired anode/electrolyte/cathode multilayers and interconnects. By cofiring technique for the multilayers, we expect to reduce the thickness of the electrolyte layers, resulting in decrease of innerimpedance, and achieve low production cost. On the other hand, the cofiring technique requires that the sintering temperature, the shrinkage profiles and the thermal expansion characteristics of all component materials should be compatible with the other. It is, therefore, difficult to cofire the multilayers with large area. Using the multilayers with surface area of 150cm{sup 2}, we fabricated the multiple cell stacks. The maximum power of 5x4 multiple cell stack (5 planes of cells in series, 4 cells in parallel in each planes 484cm{sup 2} effective electrode area of each cell planes) was 601W (0.25Wcm{sup -2}, Uf=40%). However, the terminal voltage of the multiple cell stack decreased by the cause of cell cracking, gas leakage and degradation of cofired multilayers. This paper presents the improvements of cofired multilayers, and the performance of multiple cell stacks with the improved multilayers.

A gold electrode surface was modified with the self-assembled monolayer of bis(10-(N-succinimidoxy) carbonydecyl) disulfide (1). Electrochemical properties of the electrode were characterized by cyclic voltammetry and impedance measurements. The former technique showed a surface coverage ratio of 0.34 was attained. By taking advantages of the reaction of the terminal succinimidoxy ester group of 1 and amino groups, the electrode was applied to enzyme immobilization. A possible application to an electrochemical sensor of the resulting modified electrode based on an impedimetric principle was also investigated.

A new alkanethiol derivative containing a 18-crown-6 function (1) was introduced for fabrication of electrode surface. A 1-modified gold electrode was prepared by dipping in the solution of 1. By using a [Fe(CN)6]3-/4- redox couple as an electrochemical probe, a densely packed, electrochemically insulating surface layer formation by 1 was confirmed by cyclic voltammetry. This made the amperometric sensory application of the electrode difficult. On the other hand, this property suggested a possible application to chemical sensors with electrical impedance measurements. The idea was successfully demonstrated by sensing gaseous ammonia. Organic gases such as benzene and chloroform did not give response. The surface-immobilized crown ether played a key function in determining the selectivity.

A follow-up study was performed on 264 patients of Colles' fracture (271 limbs) who were treated at Naha Prefectural Hospital from 1979 to 1985.The results were as follows: most fractures occurred at 15 to 24 years in men and after the middle age in women. Statistically the fracture type of the patient was focused on Frykman type I and II. Dorsal tilt deformity had a relationship with the deterioration of symptom (pain, swelling, limitation of motion). It is suggested that, symptom may appear according to the level of daily activity in aged patient who had residual deformity of the fracture.

We experienced nine cases of the distal tibiofibular ligament injury. The patients comprised of four fresh cases who visited our clinic within seven days after the injury and other five cases visited us later than a month after the injury. Among them, four cases were treated by operative procedure with tibia bolts, and other four cases by conservative treatment with plaster cast. One case refused our treatment.The result was as follows: All of four operated cases showed good results with very little discomfort, but no limitation in their activity of daily living. Three of conservatively treated cases showed excellent results without any complaints, and another one showed good results. The last one who refused our treatment showed poor results with limitation of ankle motions.

We have experienced a case of idiopathic bone infarction of the left distal femur. The patient, a 55-years-old femle caddy, has been suffering from severe pain at the buttock and the pain from thigh to toe during two months. She had the same episode two years ago, but the pain became free within a month.At first we suspected that the pain was caused by lumbar spinal canal stenosis. In the course of treatment pain was limited at the left knee and there was an osteosclerotic lesion at the distal metaphysis of the left femur on x-ray films. There were no inflammatory signs in the clinical, laboratory and histopathological data. Finally we have found that the pain was caused by the lesion. By the past history, clinical course, signs and histopathological findings, the lesion was diagnosed as idiopathic bone infarction.

Recently we have experienced a case of traumatic posterior dislocation of the left hip associated with fractures of the femoral head and acetabulum, with incomplete sciatic nerve injury and fracture of the proximal end of the tibia.The patient, a 29-year-old man, was injured in a motorcycle accident. As a closed reduction was unsuccessful, an open reduction was performed at thirty six hours after the accident. The lesser fragment was located in the anteromedial portion of the head and showed about a third of the femoral head in size. The fragment of the head was fixed with two screws and acetabular fragment was reattached with silk.After the operation, he was managed with traction for eleven weeks. Nine months later, he had no complaints of the hip and knee joints and x-ray films revealed no progressive changes.