Electric and mass transport of a carbon nanotube encapsulating a copper nano-rod studied by in-situ transmission electron microscopy.

Electric properties and current-induced structural changes of carbon nanotubes (CNTs) encapsulating copper nano-rods were studied by in-situ transmission electron microscopy (TEM). The diameter and the length of a copper filled CNT were 18 nm and 256 nm, respectively. The thickness of the graphite layer was about 1 nm. The bias voltage was applied between the two ends of the CNT inside the TEM, and the current as well as TEM images were recorded simultaneously. At a bias voltage of 1.4 V, the current increased to 10 microA, corresponding to a current density of 4.0 x 10(6) A/cm2, and at the same time the nano-rods inside the CNT started to move to an end of the CNT. After the movement of the nano-rods, an empty CNT was left. Resistivities of the CNT and the copper nano-rod were measured to be 3.0 x 10(-5) ohm m and 1.2 x 10(-4) ohm m, respectively.

Compact all-fiber pulsed coherent Doppler lidar system for wind sensing.

A compact 1.5 microm all-fiber pulsed coherent Doppler lidar system for wind sensing, which includes the functions of variable pulse width and automatic polarization control has been developed. The system configuration is introduced and key components used in the system are explained. Theoretical performances of the system in wind sensing are estimated and compared with experimental results. The measurable range corresponding to the detection probability of >80% is approximately 1 km or more in the case of 150 m range resolution under the normal atmospheric conditions.

11-mJ, 15-Hz single-frequency diode-pumped Q-switched Er, Yb:phosphate glass laser.

A single-frequency diode-pumped Q-switched Er, Yb:phosphate glass laser that oscillates at an eye-safe 1.54etam wavelength has been developed for use in coherent Doppler lidar. A maximum TEM(00)-mode Q-switched output energy of 10.9 mJ and a relatively long pulse width of 228 ns were obtained at a repetition rate of 15 Hz by use of a modified 2-m-long telescopic cavity. Frequency stability of as high as +/-1.9-MHz standard deviation and a side-mode suppression ratio of more than 30 dB were also achieved.

The development for polymer actuator active catheter system.

SUMMARY: Electric stimuli polymer-metal composite actuator material has been developed for active catheter system and other widely new applications. Thepolymer actuator is made of ion exchange polymer and gold as electrode, and a pulse voltage of 3 volts on the actuator gave a quick bend 90 degree angle. This composite material is possible to make small size, light and soft actuator. So now we can actually develop an active catheter for the interventional radiology surgery. The prototype polymer actuator active catheter has been developed by using polymer actuator technology and Micro Electronics Mechanical System (MEMS) technologies. The active catheter is controllable from the outside of the body by electric signal. The tip part of the catheter is made of the polymer actuator tube and bends 90 degree angles. The animal tests (dog) showed good actuator performance to control right direction and bending angle at bifurcation of blood vessel and aneurysms.

Voltammetric study of charge transfer across supported bilayer lipid membranes (s-BLMs).

Stable bilayer lipid membranes on a metal support (s-BLMs) and on an agar gel salt bridge (sb-BLMs) have been formed and their potential usefulness as practical sensors demonstrated. This paper presents the preparation method of s-BLMs and sb-BLMs, and the application of cyclic voltammetry (CV) to their investigation. The instrument and data analysis of the CV are described. The application of CV to the C60-doped BLM system is presented. This technique is a basis for biosensor development, and a useful tool for membrane research.

p53 protein expression and prognosis in gallbladder carcinoma and premalignant lesions.

BACKGROUND/AIMS: p53 protein expression in gallbladder carcinoma has recently been detected by immunohistochemical techniques, but the relationship between p53 expression and prognosis or clinico-pathological factors is still obscure. MATERIALS AND METHODS: We investigated 48 gallbladder carcinoma, 7 adenoma and 11 dysplasia cases for p53 expression by immunohistochemical techniques. RESULTS: p53 expression was positive in 39.6% of gallbladder cancer cases, but in no adenoma or dysplasia cases. No significant correlation was found between p53 overexpression and prognosis or recurrence in 20 patients with carcinoma involvement up to the subserosal layer. p53 overexpression was correlated with DNA aneuploidy pattern and the absence of stones, but was not correlated with clinical staging or lymph node metastasis. CONCLUSION: These results suggest that p53 gene mutation is related to the transition from premalignancy to malignancy in gallbladder carcinogenesis, as well as DNA ploidy alterations and carcinogenesis unassociated with gallstones, but has no bearing on the prognosis.

Ovarian small cell carcinoma with K-ras mutation: a case report with genetic analysis.

A rare case of ovarian small cell carcinoma is reported. Laboratory examination of a 46-year-old woman with a lower abdominal tumor showed marked hypercalcemia. Her condition deteriorated progressively, and she died one month after admission. A right ovarian tumor, 8 cm in diameter, metastases to multiple organs, and intraperitoneal bleeding were confirmed by autopsy. Microscopically, the small tumor cell had rounded nuclei with small distinct nucleoli and a scanty cytoplasm. Small cell carcinoma was diagnosed from these histological features and the clinical course associated with hypercalcemia. Immunohistochemical studies showed positive staining of neuron specific enolase (NSE) and keratin. Genetic analysis using DNA extracted from paraffin sections of metastatic lesions revealed mutation of K-ras codon 12. Loss of heterozygosity of the p53 and adenomatous polyposis coli (APC) genes was not informative. Previous reports have shown that ras gene mutations occur in 30% of epithelial ovarian tumors and significantly more frequently in mucinous than in other types of ovarian tumors. These results suggest that small cell carcinoma is of epithelial origin and may have a genetic alteration similar to that of mucinous tumors.

Expression of p53 protein related to human papillomavirus and DNA ploidy in superficial esophageal carcinoma.

We examined the p53 protein and human papilloma virus (HPV) by immunohistochemistry and DNA ploidy by cytofluorometry in paraffin-embedded esophageal carcinoma tissue specimens. Sixty-one patients with superficial esophageal carcinoma were operated on between 1983 and 1991 without any prior treatment. Immunostaining of the anti-p53 protein antibody (CM1) was positive in 32 carcinomas (52%). Patients with p53-positive tumors had a poorer outcome than those with p53-negative tumors (P < 0.05). In addition, patients with p53-positive tumors did not have any characteristic site of relapse. Only 5 of the 61 patients (8.2%) had HPV-positive tumors. One of these 5 carcinomas expressed both p53 protein and HPV. Three patients with HPV-positive tumors which had invaded the submucosal layer died of relapse. A determination of DNA ploidy revealed 30 patients with aneuploid tumors, 13 with polyploid tumors and 18 with diploid tumors. The outcome of the patients with aneuploid tumors was worse than that of the patients with diploid tumor (P < 0.05). p53 protein expression was not associated with DNA ploidy; however, the 16 patients who had both p53-positive and aneuploid tumors had a worse prognosis than patients with p53-negative and aneuploid tumors (P < 0.01). These findings suggest that p53 protein expression in conjunction with DNA ploidy may be a useful indicator in evaluating the prognosis of patients with superficial esophageal carcinoma.

Effect of DL-alpha-tocopherol (vitamin E) on the differentiation of mouse myeloid leukemia cell.

The effect of DL-alpha-tocopherol on the differentiation of the mouse myeloid leukemia cell line (M1) was investigated using fluorometry. The reliability of the fluorometric determination was verified by the mutual overlapping of the curves of disappearance of the radioactivity recovered as alpha-tocopherol and the loss of its fluorescence. alpha-Tocopherol solubilized into the culture medium was relatively stable (t1/2 = 147-168 hr). In corporation of alpha-tocopherol into M1 cells was time- and dose-dependent. Proliferation of M1 cells was never inhibited, but was slightly enhanced by treatment with alpha-tocopherol. alpha-Tocopherol caused a twofold increase in acid-phosphatase activity and slightly inhibited both the spontaneous- and dexamethasone-induced differentiation with respect to adhesion on glass and cell surface-rosette formation. alpha-Tocopherol also induced morphological change, making the shape of M1 cells rounder.