The apparent diffusion coefficient (ADC) in the optic nerve was measured from diffusion-weighted magnetic resonance imaging using an intravoxel incoherent motion (IVIM) sequence. The subjects were seven normal volunteers and eight patients with multiple sclerosis (MS) with a total of four optic nerves with acute neuritis and nine nerves with chronic neuritis. The mean ADC (4.18 +/- 1.13 x 10(-3) mm2/s, n = 9) in the optic nerves with chronic neuritis was significantly higher than that in normal volunteers (1.56 +/- 0.675 x 10(-3) mm2/s, n = 14) and that in the nerves with acute neuritis (0.94 +/- 0.43 x 10(-3) mm2/s n = 4) (P < 0.001). The ADC is useful in assessing MS foci in the optic nerves.

The purpose of this study was to determine if the apparent diffusion coefficient (ADC) on diffusion-weighted MRI could predict the response of patients with advanced pancreatic cancer to chemotherapy. Diffusion-weighted MRI was performed in 63 consecutive patients with advanced pancreatic cancer who were subsequently treated with chemotherapy. The ADC values of the primary tumour with a middle b-value (400 s mm(-2)) and a high b-value (1000 s mm(-2)) were determined; cystic or necrotic components were avoided. The patients were classified into two groups: (i) those with progressive disease and (ii) those who were stable 3 months and 6 months after initial treatment. The groups were compared with respect to the ADC and clinical factors, including gender, age, Union International Contre le Cancer (UICC ) stage, initial tumour size and chemotherapy agents used. Local tumour progression rates were evaluated using the Kaplan-Meier method. The middle b-value ADC of the pancreatic cancers ranged from 0.93-2.42 x10(-3) mm(2) s(-1) (mean, 1.50 x10(-3) mm(2) s(-1)), and the high b-value ADC ranged from 0.72-1.88 x10(-3) mm(2) s(-1) (mean, 1.20 x10(-3) mm(2) s(-1)). The high b-value ADC was significantly different between the progressive and stable groups at 3 months' and 6 months' follow-up (p = 0.03 and p = 0.04, respectively). The rate of tumour progression was significantly higher in those with a lower high b-value ADC than in those with a higher b-value ADC (median progression time, 140 days vs 182 days; p = 0.01). In conclusion, a lower high b-value ADC in patients with advanced pancreatic cancer may be predictive of early progression in chemotherapy-treated patients.

These results suggest that MDCT provides an accurate diagnosis with high specificity and a low false-positive rate and can be used to select the patients who are candidates for preoperative chemotherapy.

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We have measured the valence-band photoemission and inverse photoemission spectra of single-walled carbon nanotubes ͑SWNTs͒ with mean radii of 0.7 and 0.64 nm encapsulating C 60 fullerenes ͑peas͒, so-called "peapods." The photoemission spectrum of the C 60 peas in the SWNTs is obtained by subtracting the spectrum of empty SWNTs from the spectrum of the peapod. The structures in the C 60 pea spectra correspond well to those in the spectrum of a C 60 face-centered-cubic solid. No structure is observed at binding energies ranging from the Fermi level ͑E F ͒ to the onset of the highest occupied molecular orbital ͑HOMO͒ peak; the t 1u level of the C 60 peas inside the SWNT stays above E F .

A case of anomalous mesenteric artery is reported. The artery was incidentally cannulated during angiography of a patient with a left renal tumor. It arose from the abdominal aorta between the superior and inferior mesenteric arteries. The artery then ascended directly upwards from its origin and supplied the transverse colon replacing the middle colic branch of the superior mesenteric artery. The anomaly must be a result of a anomalous concentration of unpaired visceral arteries in the developing embryo. This type of anomaly is very rare and it would be appropriate to name the artery the middle mesenteric artery.

The selective and long-term deposition of iodized oil in the hepatocellular carcinoma (HCC) and its gradual drainage were clinicopathologically analyzed in 13 cases. All patients were Japanese and had an intrahepatic arterial injection of Lipiodol (LIP) mixed with Mitomycin C. The comparison among the follow-up computerized tomography (CT) findings, the observation of the soft x-ray radiogram, and histopathologic studies of the surgical or autopsy materials revealed that the selective deposition of LIP in HCC lasted for a long term, particularly in cases treated by LIP combined with transcatheter arterial embolization (TAE). Also revealed was an extremely gradual decrease of LIP from the HCC. It was thus postulated that, mainly, the accumulated macrophages surrounding LIP around the necrotic cancer tissue and, partially, the intrahepatic lymphatic system itself contributed to this drainage. Further, in histologic sections with lipid staining, x-ray microanalysis proved that the lipid droplets in the cancer tissue included highly concentrated iodine, as a deposition of LIP.

No abstract