Search

Objective: To compare the capability of differentiation of small-cell lung cancer (SCLC) from non-SCLC (NSCLC) between diffusion-weighted imaging (DWI) and short tau inversion recovery (STIR) turbo spin-echo imaging. Methods: The institutional review board of Kobe University Hospital, Kobe, Japan, approved this study, and written informed consent was obtained from each patient. 49 patients with NSCLC (30 males and 19 females; mean age, 66.8 years) and 7 patients with SCLC (5 males and 2 females; mean age, 68.6 years) enrolled and underwent DWI and STIR. To quantitatively differentiate SCLC from NSCLC, apparent diffusion coefficient (ADC) values on DWI and contrast ratios (CRs) between cancer and muscle on STIR were evaluated. ADC values and CRs were then compared between the two cell types by Mann-Whitney's U-tests, and the diagnostic performances were compared by McNemar's test. Results: There were significant differences of mean ADC values (p< 0.001) and mean CRs (p = 0.003). With adopted threshold values, the specificity (85.7%) and accuracy (85.7%) of DWI were higher than those of STIR (specificity, 63.3%; p = 0.001 and accuracy. 66.1%; p = 0.001). In addition, the accuracy of combination of both indexes (94.6%; p = 0.04) could significantly improve as compared with DWI alone. Conclusion: DWI is more useful for the differentiation of SCLC from NSCLC than STIR, and their combination can significantly improve the accuracy in this setting. Advances in knowledge: Pulmonary MRI, including DWI and STIR, had a potential of the suggestion of the possibility as SCLC. [ABSTRACT FROM AUTHOR]

This study aimed at prospectively compared efficacy of non-contrast-enhanced (non-CE) MRI and MDCT for management of pulmonary nodules. A total of 161 patients with 200 nodules underwent MDCT and non-CE MRI (T1WI, T2WI, and STIR) in conjunction with pathological and/or more than 2 years of follow-up examinations. To compare qualitative detection rates between both modalities, all nodules were visually assessed. To compare quantitative and qualitative diagnostic capabilities of MRI, calculation of contrast ratio and visual assessment of probability for malignancy in each nodule were performed. Then, detection rate and diagnostic capability were statistically compared. Although the overall detection rate of each MR sequence (82.5%) was significantly lower than that of MDCT (97.0%, p<0.05), that of malignant nodules showed no significant difference (p>0.05). The diagnostic capability of STIR was significantly higher than those of other MR sequences (p<0.05). Non-CE MR imaging was found to be as useful as MDCT for management of pulmonary nodules. [ABSTRACT FROM AUTHOR]

Single-wall carbon nanotubes (SWNTs) encapsulating fullerenes, so-called fullerene peapods, were synthesized in high yield by using diameter-selected nanotubes as pods. Transmission electron microscopy revealed high-density fullerene chains inside the nanotubes. X-ray-diffraction measurements indicate 85% filling for C60 and 72% filling for C[sub70] molecules as a total yield. Interestingly, C[sub60] peas do not show any thermal expansion while C[sub70] peas show normal behavior. Room-temperature Raman spectra show one-dimensional photopolymerization of C[sub60] inside nanotubes by blue-laser irradiation, suggesting molecular rotation inside them. In C[sub70] peapods, no photopolymerization was observed but the relative Raman intensity of each peak is different from the C[sub70] 3D crystal. This is probably caused by mixing of two different crystal structures in C[sub70] peas. Furthermore, we synthesized Zn-diphenylporphyrin peapods. Optical absorption and Raman spectra suggest that the encapsulated molecules are deformed by interaction with the SWNT. [ABSTRACT FROM AUTHOR]

Purpose: Mutation of the p53 gene and deregulation of telomerase may be essential for canceration in some malignant diseases. However, relationships between these occurrences have not yet been clarified. We examined the roles of p53 gene mutation and telomerase activity relative to the clinical and pathologic features of non-small cell lung carcinoma (NSCLC).Methods: Frozen sections of 40 surgically resected NSCLC specimens were used. DNA extracted from fresh tumor specimens was analyzed with polymerase chain reaction (PCR), single-strand conformation polymorphism (SSCP) method, to screen alterations in the p53 gene. Exons showing aberrant band shifts on SSCP were reamplified, and the PCR products were directly sequenced. In addition, the telomerase activity of the same specimens was analyzed quantitatively with the fluorescence-based telomeric repeat amplification protocol assay, and the total product generated (TPG) method. Clinical and pathologic parameters were evaluated using a statistical analysis system.Results: Mutations of the p53 gene relevant to an altered protein were confirmed in 19 of 40 specimens (47.5%). The TPG of 40 specimens was 75.24 +/- 15.55 (mean +/- SE). The TPG of the 19 specimens positive for p53 gene mutation was significantly higher than that of the 21 specimens negative for p53 gene mutation. Furthermore, the degree of cell differentiation was significantly correlated with both p53 gene mutation and high telomerase activity.Conclusions: p53 gene mutation and high telomerase activity cooperate to induce tumorigenesis and low-grade differentiation in NSCLC. Simultaneous occurrence of p53 gene mutation and high telomerase activity may be relevant to the grade of malignancy in NSCLC. [ABSTRACT FROM AUTHOR]

This study concerns a patient with minor (m)-BCR/ABL transcript-positive and Philadelphia (Ph) chromosome-negative myelodysplastic syndrome (MDS). The patient was a 78-year-old man whose condition was diagnosed as refractory anemia with excess of blasts in transformation. Molecular genetic studies, using reverse transcriptase polymerase chain reaction analysis detected m-BCR/ABL messenger RNA. We used spectral karyotyping to analyze metaphase cells but could not detect a Ph chromosome. Fluorescence in situ hybridization, however, revealed fusion signals of BCR and ABL probes on an apparently normal chromosome 22. [ABSTRACT FROM AUTHOR]

A detailed three-dimensional structural analysis of single-walled carbon nanotubes was carried out using a scanning tunneling microscope (STM) operated at room temperature in ambient conditions. On a microscopic scale, the images show tubes condensed in ropes as well as tubes which are separated from each other. For a single-wall nanotube rope, the outer portion is composed of highly oriented nanotubes with nearly uniform diameter and chirality. On separated nanotubes, atomically resolved images show variable chirality ranges between 0°–30°, and variable diameter (1–3 nm), with no one type dominant. From STM and scanning tunneling spectroscopy measurements we confirmed the correlation between chirality and the electronic properties, namely the tuning from metallic to semiconducting. We also observed a rectifying behavior correlated with the chiral angle of 25°, an important observation for nanodevices application. © 1998 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The hydroacoustic system to count the numbers of sea fish with precision have been studied. Experiments have been performed on fish cultivated in culturing nets, numbers of which have been counted manually. In this system, the volume of fish school and their distribution density are separately measured by applying the principles of the fish finder and then the number of fish are determined by multiplying one by another. The approximate volume is determined by the shape of section of fish school which is displayed by using the principle of PPI sonar. The ultrasonic waves reflected from fish in the effective volume are compounded. Accordingly, the number of fish in the effective volume is obtained from the intensities of the reflected waves. The distribution density is calculated by dividing the number by the effective volume. In the case of good distribution of fish, the error is within ±5%. It is expected that such a system will be extended to the measurement of fish stocks. [ABSTRACT FROM AUTHOR]