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Notes: Summary ¶ The authors report a rare case of primary intracranial malignant schwannoma of the trigeminal nerve occuring in a 30-year-old woman without von Recklinghausen's neurofibromatosis (VRNF). The tumour arose from the intracranial part of the left trigeminal nerve, without skull base destruction. The tumour was partially removed operatively, followed by focal 50Gy irradiation, but unfortunately the tumour showed rapid regrowth. A second operation was attempted, but she died of cerebral infarction soon after operation. Histologically, the original tumour was characterized by the presence of foci of extremely high cellularity, pleomorphism and mitosis in an otherwise typical benign schwannoma. Immunohistochemically, the tumour cells were positive for S-100 protein even in the atypical areas, suggesting the tumour to be of Schwann cell origin. However, the recurrent tumour was composed of undifferentiated spindle cells, which were negative for S-100 protein.  Thus, it is possible to consider that the S-100 protein expression could reflect the degree of differentiation of Schwann cells. Furthermore, the postoperative irradiation might have exacerbated the malignant progression in the present case.

Notes: Superplastic behaviors were investigated for fine-grained yttria-stabilized tetragonalzirconia polycrystal (Y-TZP) from a viewpoint of GeO2 or TiO2 doping. It was found that bothdopants enhance the ductility in TZP. In particular, elongation to failure of 988% could be obtainedin 3Y-TZP co-doped with 2mol%GeO2 and 2mol%TiO2. In addition, it was revealed that lower flowstress did not always give a larger elongation in this system. On the other hand, the strongsegregation of dopants along grain boundaries was confirmed by high-resolution electrontransmission microscopy study (HRTEM) with X-ray energy dispersive spectrometer (EDS). Theunique phenomena observed in the relation between flow stress and ductility is closely related to thestrong segregation of dopants along grain boundaries in this system. The grain size at fracture isdetermined by covalency because of the dopant segregation. It could be concluded that elongationto failure is closely related to a balance between grain size at fracture and grain growth rate duringdeformation

Notes: We observed the internal structure of an oil/wax/water/surfactant system using a scanning electron microscope to investigate the relationship between its hardness and state of wax crystal. The molten wax (hydrogenated jojoba oil, ceresin, polyethylene wax, carnauba wax, or microcrystalline wax) was cast in a home-made spiral mold of aluminum foil for preparing the test specimen for SEM observation. In hydrogenated jojoba oil a fine frame-like crystal structure, the so-called ‘card-house structure,’ was observed but not in other waxes. The mixture of hydrogenated jojoba oil and water showed a few small droplets deposited on the roundish wax frame-like structure. On the other hand, waxes other than hydrogenated jojoba oil did not change their internal structure when they were mixed with water. This result suggested that hydrogenated jojoba oil showed uniquely high affinity for water. In the system of oil, water, surfactant, and various kinds of waxes, their crystal structure, hardness, and the shape of dispersed water particles were remarkably changed with the combination of waxes. In the system with ceresin and carnauba wax, the hardness measured by a card-tension meter was high, and the internal crystal structure was fine and amorphous. The water particle in the ceresin and carnauba wax system had a smaller diameter than that in the system containing hydrogenated jojoba oil. The system containing hydrogenated jojoba oil showed a card house-like wax crystal structure without high hardness. It was considered that the wax crystal structure played an important role in providing hardness and in contributing to the water distribution in the oil/wax/water/surfactant system.

Notes: Background, aims: The present study was undertaken to assess the periodontal status of a rural Japanese population and to study the correlation between the periodontal status and the serum antibody titers for Porphyromonas gingivalis (Pg) fimbriae.Method: A total of 236 individuals were examined for their periodontal conditions by the use of the community periodontal index for treatment needs (CPITN), and serum antibody titers for Pg fimbriae in their peripheral blood samples were evaluated using the enzyme-linked immunosorbent assay.Results: There was a substantially larger proportion of edentulous subjects in the age group older than 60 years. The remaining teeth were 24.1, 23.2, 11.1 and 10.1 per person in the 40–49, 50–59, 60–69 and 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE280311:ges" location="ges.gif"/〉70 age groups, respectively. The % of sextants with a CPITN code of missing sextant (MS) increased towards elderly and reached 〉60% in the age group of 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE280311:ges" location="ges.gif"/〉70 years, as the % of the CPITN 2, 1 or 0 sextant decreased. The % of CPITN 4 and 3 sextants did not differ between different age groups and were about 6–8% and 15–20%, respectively. The % of CPITN 1 or 0 sextants was higher in female subjects than in male subjects in the 60–69 and 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE280311:ges" location="ges.gif"/〉70 age groups, while the % of CPITN 4 or 3 sextants was higher in male subjects than in female subjects in all age groups. There was no significant difference between various age groups in the mean serum antibody titers for Pg fimbriae. The mean anti-Pg fimbriae antibody titers was significantly higher for the subjects with a maximum CPITN code 4 (max.-CPITN 4 subject) than for the subjects with lower maximum CPITN codes. The antibody titers varied extensively among the max.-CPITN 4 or 3 subjects, but not among the max.-CPITN 2/1/0 or MS subjects.Conclusions: The present study demonstrated that tooth loss is a remarkable event in elderly subjects and that oral prophylaxis and mechanical debridement should be mandatory in the population examined. It was also demonstrated that the serum antibody titers against Pg fimbriae could be useful for screening individuals with moderate to severe periodontitis.

Notes: We report on a periodic traveling-wave photodetector (P-TW-PD) fabricated by unicarrier traveling photodiodes (UTC-PDs). It is comprised of three UTC-PDs periodically arranged along a coplanar waveguide transmission line. The photoresponse of the P-TW-UTC-PD is three times that of a single UTC-PD. A 3 dB bandwidth (f3dB) of 115 GHz at 1.55 μm was observed in a P-TW-UTC-PD with a terminal resistor located at the input end. This value of f3dB is almost the same as that observed in a single UTC-PD. In P-TW-UTC-PDs with no terminal resistor, the 3 dB bandwidth degrades to 56 GHz as a result of the reflection of backward-propagating microwaves at the input end. We conclude that our P-TW-UTC-PD provides velocity matching between electrical and optical waves. © 2001 American Institute of Physics.

Notes: Background : The incidence and severity of non-steroidal anti-inflammatory drugs (NSAIDs)-induced gastro-duodenal ulcer have not been extensively studied in Japan.Aim : We performed a prospective study to clarify NSAIDs-induced gastro-duodenal injury, focusing especially on low-dose aspirin (L-A).Methods : Two hundred and thirty-eight patients with bleeding peptic ulcers admitted to our hospital. History of taking NSAIDs and anti-ulcer drugs was obtained from all patients who underwent endoscopic examinations. The lesion scores of patients taking L-A were classified numerically from zero (no lesion) to five (ulcer).Results : The NSAIDs were associated with 28.2% of hemorrhagic ulcers. The rates of patients using L-A, loxoprofen, diclofenac, and combination of two of these drugs were 27, 16, 10 and 9%, respectively. Co-administered anti-ulcer drugs were cytoprotective anti-ulcer drugs (27%), H2 receptor antagonists (16%), PPI (4%), and none (53%). In patients taking L-A, H2 receptor antagonists were used most frequently. The HP was positive in 63% of L-A-induced ulcer cases and in 69% of NSAIDs other than low-dose aspirin-induced ulcer cases. The lesion scores of patients taking L-A with H2 receptor antagonists or PPI were significantly lower than those of patients who were taking only L-A (P 〈 0.05).Conclusions : Approximately one-third of hospitalized patients with NSAIDs-induced hemorrhagic ulcer showed an association with L-A. Prospective randomized controlled trials including H2 receptor antagonists are required to establish preventive efforts aimed at L-A-induced gastro-duodenal injury.

Notes: Histological changes in the hypofunctional pituitary gland following conventional radiotherapy for adenoma Aims: Although delayed hypopituitarism is a common complication of conventional radiotherapy of sellar tumours, histological changes that may account for it have been rarely reported. To elucidate the changes, hypofunctional pituitary glands following irradiation were studied. Methods and results: Two pituitary glands obtained at autopsy from patients who had been irradiated for adenoma and exhibited hypopituitarism were examined. In both cases diffuse fibrosis was observed in the adenohypophysis, whereas the neurohypophysis remained unchanged. Immunohistochemistry showed that stellate-shaped S100 protein-positive cells were increased in number and distributed among the endocrine cells. Some irradiated endocrine cells showed dense granular immunoreactivity for mitochondrial protein, cytochrome oxidase and manganese-superoxide dismutase. In addition to faint reactivity with anti-cytokeratin 8, 18 antibody, many cells were densely positive with anti-cytokeratin 1, 5, 10, 14 antibody. Conclusions: These results indicate that radiation- induced fibrosis is associated with an increased number of folliculo-stellate cells and the presence of metabolic dysfunctional mitochondria resembling mitochondria in oncocytes. Squamous metaplasia in the irradiated endocrine cells was also noted. Various intracellular changes may participate in delayed pituitary hypofunction following radiotherapy.