Ring and unimodal angular-frequency distribution of THz emission from two-color femtosecond plasma spark.

We study angular and frequency-angular distributions of the terahertz (THz) emission of the low-frequency region (0.3-3 THz) from a two-color femtosecond plasma spark experimentally and in three-dimensional numerical simulations. We investigate the dependence of the angular shapes of the THz radiation on focusing conditions and pulse durations by using two laser facilities (pulse durations 35 and 150 fs) for different focusing geometries. Our experiments and simulations show that decrease in the numerical aperture from NA ≈0.2 to NA ≈0.02 results simultaneously in (I) squeezing of the THz angular distribution and (II) formation of the bright conical emission in the THz range. The moderate focusing NA ≈0.05, which forms the relatively narrow unimodal THz angular distribution, is identified as optimal in terms of angular divergence. Numerical simulations with carrier wave resolved show that bright THz ring structures appear at the frequencies ≥2 THz for longer focuses (NA ≈0.02), while for optimal focusing conditions NA ≈0.05 the conical emission develops at THz frequencies higher than 10 THz.

Fractional change in apparent diffusion coefficient as an imaging biomarker for predicting treatment response in head and neck cancer treated with chemoradiotherapy.

BACKGROUND AND PURPOSE: ADC provides a measure of water molecule diffusion in tissue. The aim of this study was to evaluate whether the fractional change in ADC during therapy can be used as a valid predictive indicator of treatment response in head and neck squamous cell carcinoma treated with chemoradiotherapy. MATERIALS AND METHODS: Forty patients underwent DWI at pretreatment and 3 weeks after the start of treatment. The pretreatment ADC, fractional change in ADC, tumor regression rate, and other clinical variables were compared with locoregional control and locoregional failure and were analyzed by using logistic regression analysis and receiver operating characteristic analysis. Furthermore, progression-free survival curves divided by the corresponding threshold value were compared by means of the log-rank test. RESULTS: The fractional change in ADCprimary, the fractional change in ADCnode, primary tumor volume, nodal volume, tumor regression ratenode, N stage, and tumor location revealed significant differences between locoregional failure and locoregional control (P < .05). In univariate analysis, the fractional change in ADCprimary, fractional change in ADCnode, tumor regression ratenode, N stage, and tumor location showed significant association with locoregional control (P < .05). In multivariate analysis, however, only the fractional change in ADCprimary was identified as a significant and independent predictor of locoregional control (P = .04). A threshold fractional change in ADCprimary of 0.24 revealed a sensitivity of 100%, specificity of 78.7%, and overall accuracy of 84.8% for the prediction of locoregional control. Progression-free survival of the 2 groups divided by the fractional change in ADCprimary at 0.24 showed a significant difference (P < .05). CONCLUSIONS: The results suggest that the fractional change in ADCprimary is a valid imaging biomarker for predicting treatment response in head and neck squamous cell carcinoma treated with chemoradiotherapy.

Ferromagnetic quantum critical point in heavy-fermion iron oxypnictide Ce(Ru(1-x)Fe(x))PO.

We have performed (31)P-NMR measurements on Ce(Ru(1-x)Fe(x))PO in order to investigate ferromagnetic (FM) quantum criticality, since a heavy-fermion (HF) ferromagnet CeRuPO with a two-dimensional structure turns into a HF paramagnet by an isovalent Fe substitution for Ru. We found that Ce(Ru(0.15)Fe(0.85))PO shows critical fluctuations down to ~0.3 K, as well as the continuous suppression of Curie temperature and the ordered moments by the Fe substitution. These experimental results suggest the presence of a FM quantum critical point (QCP) at x~0.86, which is a rare example among itinerant ferromagnets. In addition, we point out that the critical behaviors in Ce(Ru(0.15)Fe(0.85))PO share a similarity with those in YbRh(2)Si(2), where the local criticality of f electrons has been discussed. We reveal that Ce(Ru(1-x)Fe(x))PO is a new system to study FM quantum criticality in HF compounds.

Intermittent hepatic artery antibiotic infusion therapy for pyogenic hepatic abscess.

PURPOSE: To study the efficacy and problems associated with intermittent hepatic artery antibiotic infusion therapy for pyogenic hepatic abscess. MATERIAL AND METHODS: The material comprised eight patients with pyogenic hepatic abscess in whom percutaneous drainage could not be performed and intravenous administration of antibiotics was ineffective. An injection catheter was introduced into the common hepatic artery. Almost the same dose of antibiotics as with intravenous administration was infused intra-arterially 2-4 times per day. RESULTS: A therapeutic effect was achieved in six of the eight cases. In these 6 cases, the mean period of intra-arterial infusion was 10.8 days, while the mean period of catheter placement was 14.7 days. Using broad spectrum antibiotics, the therapeutic effect was obtained regardless of the numbers, morphologic characteristics, and differences in location of the abscesses. No significant complications were noted except in one case of splenic infarction. CONCLUSION: Intermittent hepatic artery antibiotic infusion therapy is useful as an alternative therapeutic procedure for pyogenic hepatic abscess in which percutaneous drainage cannot be performed and intravenous administration of antibiotics is ineffective.

Comparison of high-resolution contrast-enhanced 3D MRA with digital subtraction angiography in the evaluation of hepatic arterial anatomy.

AIM: To evaluate the validity of high-resolution contrast-enhanced three-dimensional magnetic resonance angiography (MRA) in defining hepatic arterial anatomy and to compare this with digital subtraction angiography (DSA). MATERIALS AND METHODS: MRA and DSA were performed in 30 patients. MRA was performed with breath-hold, gadolinium-enhanced, three-dimensional, fast low-angle shot sequence with a 512 pixel matrix. MRA was compared with DSA in terms of image quality and depiction of hepatic arterial anatomy. The agreement in image quality between MRA and DSA was determined with the kappa statistic. RESULTS: With respect to image quality, there was excellent or good correlation between MRA and DSA for the common hepatic artery (kappa=0.85), proper hepatic artery (kappa=0.72), gastroduodenal artery (kappa=0.70), left hepatic artery (kappa=0.49), left gastric artery (kappa=0.50), splenic artery (kappa=0.84), and superior mesenteric artery (kappa=0.88). Poor correlation was found for the right hepatic artery (kappa=0.18) and right gastric artery (kappa=0.38). With regard to hepatic arterial anatomy, MRA correlated correctly with DSA in 28 of the 29 cases, i.e. 97% of patients. CONCLUSION: MRA is a useful technique for the evaluation of the hepatic artery, and for the vast majority of patients, MRA can replace intra-arterial DSA.

[Issues in cancer pain management].

In this article, three aspects of recent issues in cancer pain management such as pain assessment, drowsiness with morphine, and problem in home care setting. First, the assessment of 'impact of pain' is to assess whether the treatment is sufficient for the patient. On the other hand, assessment of 'pain intensity' is the effectiveness of the treatment. Therefore, to reduce the gap in pain evaluations between cancer patients and medical stuffs by assessing the 'impact of pain' in addition to 'intensity of pain'. Second, increasing dosage of morphine often reduces pain, at the same time patients become drowsy. This is often observed soon after starting morphine administration, especially, patients who have renal dysfunction. An active morphine metabolite morphine-6-Glucuronide is excreted into urine, so that, renal dysfunction causes drowsiness. Third, at home care setting, patients tend to be into poor pain control condition. It is necessary that paying attention on patient's knowledge of medications and having support program for pain management for home care setting.

A comparative study between MR sialography and salivary gland scintigraphy in the diagnosis of Sjögren syndrome.

PURPOSE: The purpose of this work was to compare the diagnostic accuracy of MR sialography with that of salivary gland scintigraphy in Sjögren syndrome. METHOD: One hundred thirty patients clinically suspected of having Sjögren syndrome were examined by MR sialography and salivary gland scintigraphy. A labial gland biopsy was performed in all patients. Imaging findings of MR sialography and salivary gland scintigraphy were compared with the results of labial gland biopsy. RESULTS: From the results of labial gland biopsy, the diagnosis of Sjögren syndrome was established in 80 patients. Abnormally high T2 signal intensity areas on MR sialography and decreased uptake and delayed excretion of [(99m)Tc]pertechnetate on salivary gland scintigraphy were well seen in patients with Sjögren syndrome. For the diagnosis of Sjögren syndrome, salivary gland scintigraphy showed higher sensitivity than MR sialography. On the other hand, MR sialography showed higher specificity and positive predictive value (PPV) than salivary gland scintigraphy. Overall diagnostic accuracy was 83% for MR sialography and 72% for salivary gland scintigraphy. CONCLUSION: The high PPV of MR sialography suggests that MR sialography is the preferred imaging modality in patients suspected of having Sjögren syndrome.

Creutzfeldt-Jakob disease: serial changes on diffusion-weighted MRI.

We present serial changes on diffusion-weighted MRI (DWI) in a patient with Creutzfeldt-Jakob disease (CJD). DWI revealed serial changes of abnormal hyperintense lesions that had become more extensive and conspicuous with progression of neurologic findings, more sensitively than conventional MRI. In the late stage, disappearance of abnormal hyperintense lesions on DWI was observed. DWI proved to be particularly useful for monitoring the progression of CJD.

Use of morphine and adjuvant drugs according to the condition.

Adjuvant drugs are used to enhance effects of analgesics and morphine-resistant pain such as neuropathic pain. If morphine provides inadequate pain relief and evokes drowsiness, morphine is usually ineffective. The key is the patient's reaction to morphine. When a patient's pain includes neuropathic pain, a combination of morphine and non-steroidal anti-inflammatory drugs is partially effective, but morphine-resistant pain remains. Increasing morphine dosage causes drowsiness without pain improvement. Appropriate adjuvant drugs are necessary in these conditions.

Wall correction factors for calibration of plane-parallel ionization chambers with high-energy photon beams.

Most dosimetry protocols recommend that calibration of plane-parallel ionization chambers be performed in an electron beam of sufficiently high energy by comparison with cylindrical chambers. For various plane-parallel chambers, the 1997 IAEA TRS-381 protocol includes an overall perturbation factor pQ for electron beams, a wall correction factor p(wall) for a 60Co beam and the product of two wall corrections k(att)k(m) for 60Co in-air calibration. The recommended values of p(wall) for plane-parallel chambers, however, are limited to certain phantom materials and a 60Co beam, and are not given for other phantom materials and x-ray beams. In this work, the p(wall) values of the commercially available NACP, PTW/Markus and PTW/Roos plane-parallel chambers in a solid water phantom have been determined with 60Co and 4 and 10 MV photon beams. The k(att)k(m) values for the NACP and PTW/Markus chambers have also been obtained. The wall correction factors p(wall) and k(att)k(m) have been determined by intercomparison with a calibrated Farmer chamber. The average value of p(wall) for these plane-parallel chambers was 1.005 +/- 0.1% (1 SD) for 60Co beams and 1.007 +/- 0.2% (1 SD) for both 4 MV and 10 MV photons. The k(att)k(m) values for the NACP and PTW/Markus chambers were about 1.5% lower than other published data.

[Assessment of functional severity on in vivo hepatic 31P-MRS in diffuse hepatic disease: comparative studies with 99mTc-GSA].

The purpose of this study was to compare the assessment of functional severity on in-vivo hepatic 31P-MRS in diffuse hepatic disease with functional severity assessed with 99mTc galactosyl serum albumin (99mTc-GSA). 31P-MRS was performed in 10 healthy control subjects and 16 patients with diffuse hepatic disease. Data were expressed as peak area ratios: PME/beta-ATP, PDE/beta-ATP, PME/PDE, Pi/beta-ATP, and PME/Pi. The functional severity of hepatic damage was evaluated visually and quantitatively (HH15, LHL15) by 99mTc-GSA in the group of patients with diffuse hepatic disease. Visual evaluation was classified into four grades based on anterior images of cardiac blood-pool and liver. We studied the correlation of spectral metabolic ratios and functional severity by 99mTc-GSA. We found statistically significant differences (ANOVA) among the classifications of Grade I, Grade II, and Grade III with both PME/beta-ATP and PME/PDE. A statistically significant direct correlation was found between HH15 and both PME/beta-ATP and PME/PDE. A significant inverse correlation was also seen between LHL15 and both PME/beta-ATP and PME/PDE. The studies comparing 31P-MRS with functional severity assessed by 99mTc-GSA showed that PME/beta-ATP and PME/PDE were useful for the assessment of functional severity in patients with diffuse hepatic disease.

Dose calculation for asymmetric photon fields with independent jaws and multileaf collimators.

We have developed a simple method for dose calculation in dual asymmetric open and irregular fields with four independent jaws and multileaf collimators. Our calculation method extends the scatter correction method of Kwa et al. [Med. Phys. 21, 1599-1604 (1994)] based on the principle of Day's equivalent-field calculation. The scatter correction factor was determined by the ratio of the derived doses of a smaller asymmetric open field or irregular field to a larger symmetric field. The algorithm with the scatter correction method can be calculated from output factors, tissue maximum ratios, and off-axis ratios for conventional symmetric fields. The doses calculated by this method were compared with the measured doses for various asymmetric open and irregular fields. The agreement between the calculated and measured doses for 4 and 10 MV photon beams was within 0.5% at the geometric center of the asymmetric open fields. For the asymmetric irregular fields with the same geometrical center, agreement within 1% was found in most cases.

MR imaging of subchondral osteonecrosis of the vertebral body after percutaneous laser diskectomy.

OBJECTIVE: We describe four cases of subchondral osteonecrosis of the vertebral body that occurred after percutaneous laser diskectomy. Follow-up MR imaging after laser intervention showed abnormal findings in the vertebral body immediately adjacent to the site of diskectomy that are consistent with subchondral osteonecrosis. CONCLUSION: MR imaging features of this complication include a wedge-shaped low signal intensity on T1-weighted images, high and low signal intensities on T2-weighted images, and a contrast-enhanced area corresponding to high signal intensity on T2-weighted images. Possible causative mechanisms include thermal injury and photoacoustic shock.

Emotional eating and eating psychopathology in nonclinical groups: a cross-cultural comparison of women in Japan and the United Kingdom.

OBJECTIVE: Emotional eating is associated with eating psychopathology among Western populations. It is not known whether the same conclusions hold in non-Western cultures, where norms for emotional expression differ. This study examined whether emotional eating has the same eating psychopathology correlates in different cultures. METHOD: Three groups of nonclinical women were compared-Japanese living in Japan; Japanese living in the United Kingdom; and British living in the United Kingdom. They completed an Emotional Eating Scale and the Eating Disorders Inventory. RESULTS: There were different patterns of association between emotional eating and eating attitudes in the three groups. British women showed a strong linkage, Japanese women living in Japan showed no association, and Japanese women in the United Kingdom showed an intermediate pattern. CONCLUSIONS: Emotional eating may be less of an index of eating psychopathology in non-Western cultures. However, there appears to be an acculturative process, linking the two when one enters a Western culture. This cross-cultural difference may have implications for the targeting of therapies, although this conclusion requires support from further research.

MR sialography in patients with Sjögren syndrome.

PURPOSE: The purpose of this study was to evaluate the effectiveness of MR sialography of the parotid gland ducts in the diagnosis and staging of Sjögren syndrome. METHODS: MR imaging was performed on a 1.5-T unit with a neck phased-array coil. MR sialographic source images were obtained using a heavily T2-weighted fast spin-echo sequence with spectral fat suppression. All images were analyzed on the basis of maximum intensity projection reconstruction. Five healthy control subjects and 51 patients with definite Sjögren syndrome (43 with primary disease and eight with secondary disease) were examined with MR sialography. A labial gland biopsy was performed in all patients and histopathologic grading was done by means of focal scores. The findings of MR sialography were compared with the results of labial gland biopsy to determine the effectiveness of the technique in the diagnosis and staging of Sjögren syndrome. RESULTS: In all five control subjects, the main duct and the primary branching ducts of the parotid glands were clearly visible on MR sialographic images. In patients with Sjögren syndrome, a punctate, globular, cavitary, or destructive appearance was well seen within the parotid glands. Findings obtained at MR sialography correlated well with the results of labial gland biopsy. CONCLUSION: MR sialography has the potential to produce diagnostic findings in the parotid gland ducts of patients with Sjögren syndrome. Our results suggest that this method will augment and possibly replace X-ray sialography.

[Echo-planar FLAIR imaging in patients with brain disorders: comparative studies with turbo-SE T2WI and turbo-FLAIR].

Fluid-attenuated inversion-recovery (FLAIR) imaging is a technique that produces heavily T2-weighted CSF-nulled images by coupling an inversion pulse followed by long inversion time (TI) to a long echo time (TE) readout. With nulling of the CSF, a tissue abnormality usually becomes the brightest object in the image, thereby improving lesion detection in the brain. The FLAIR technique is also easily adapted to echo-planar imaging (EPI), the most rapid MR imaging technique available. We examined EPI-FLAIR imaging in patients with brain disorders and compared the results with those of turbo-FLAIR and turbo SE T2-weighted imaging. MR imaging was performed on a 1.5 T imager in 29 patients with cerebral infarction and 2 patients with multiple sclerosis. The turbo-SE T2-weighted sequence parameters used were: TR/TE = 4000 ms/99 ms, total scan time = 2 min 12 sec. Turbo-FLAIR sequence parameters were TR/TE/TI = 9000 ms/119 ms/2200 ms, total scan time = 4 min 3 sec. EPI-FLAIR sequence parameters were TE/TI = 60 ms/2200 ms, total scan time = 4.38 sec. EPI-FLAIR images were compared quantitatively and qualitatively with both turbo-FLAIR and turbo-SE T2-weighted images. In the quantiative comparisons of EPI-FLAIR images with turbo-FLAIR and turbo-SE T2-weighted images, lesion-to-white matter contrast and the C/N ratio of EPI-FLAIR images were found to be significantly inferior to both turbo-FLAIR and turbo-SE T2-weighted images (P < 0.001). In the qualitative comparisons, the lesion detection and conspicuty of EPI-FLAIR images were inferior to those of turbo-FLAIR and turbo-SE T2-weighted images. In conclusion, the image quality of EPI-FLAIR images was inferior to that of both turbo-FLAIR and turbo SE T2-weighted images. EPI-FLAIR should not replace turbo-FLAIR.

[Comparative studies on the antitumor activities and side effects of segmental SMANCS/Lip-TAE with segmental SMANCS/Lip-TAI for hepatocellular carcinoma].

We compared the effectiveness of treatments and the influence of side effects on liver function and clinical symptoms between segmental SMANCS/ Lip TAI and segmental SMANCS/Lip-TAE. The early tumor response rate of the group treated by TAI was 23.6%, and that of the group treated by TAE was 80.0%. In the group treated by TAE, the therapeutic effects were better in the nodular type than in the diffuse type of HCC, and we were also able to obtain a good tumor response rate on the multiple HCC and large HCC. However, there was no difference in the response period between the groups treated by TAI and TAE. In both groups, there were no significant differences in the appearance rate and degree of side effects. In conclusion, segmental SMANCS/Lip-TAE seemed to be an effective treatment for HCC without any serious complications.

Long-term effects of delapril hydrochloride on procollagen type III amino-terminal peptide, left ventricular mass and left ventricular function in hypertensive patients.

The long-term effect of delapril hydrochloride, a non-sulfhydryl angiotensin converting enzyme inhibitor, on serum concentrations of procollagen type III amino-terminal peptide (PIIIP) and left ventricular mass (LVM) and function were investigated in 15 hypertensive patients. Patients were treated with delapril hydrochloride 30 mg/day po for 12 months. Blood samples and an echocardiogram were obtained before treatment and after 6 and 12 months of treatment. Blood pressure, PIIIP, and LVM significantly decreased associated with an increase in left ventricular fractional shortening and mean systolic and diastolic posterior wall velocity at 6 and 12 months of treatment. Positive correlations between PIIIP and LVM (r=0.49, p<0.005) and negative correlations between PIIIP and left ventricular fractional shortening (r=-0.31, p<0.05) were found. Delapril hydrochloride reduced PIIIP and LVM and improved cardiac function in hypertensive patients.

Excellent acceleration of the Diels-Alder reaction by microwave irradiation for the synthesis of new fluorine-substituted ligands of NMDA receptor.

A series of 6,11-ethanobenzo[b]quinolizinium derivatives was synthesized through the Diels-Alder reaction between azoniaanthracne and the corresponding 1,1-disubstituted olefin. After a systematic investigation for achieving rapid synthesis, it was found that the reaction is accelerated in polar media such as H2O and trifluoroethanol. In particular, excellent acceleration was effected by microwave irradiation. The new fluorine-substituted ligands thus obtained exhibited potential affinity toward NMDA receptors.

Characterization of 5,7-dichlorokynurenate-insensitive D-[3H]serine binding to synaptosomal fraction isolated from rat brain tissues.

To explore target sites for endogenous D-serine that are different from the glycine site of the N-methyl-D-aspartate (NMDA) type glutamate receptor, we have studied the binding of D-[3H]serine to the synaptosomal P2 fraction prepared from the rat brain and peripheral tissues in the presence of an excess concentration (100 microM) of the glycine site antagonist 5,7-dichlorokynurenate (DCK). Nonspecific binding was defined in the presence of 1 mM unlabeled D-serine. Association, dissociation, and saturation experiments indicated that D-[3H]serine bound rapidly and reversibly to a single population of recognition sites in the cerebellar P2 fraction in the presence of DCK, with a K(D) of 614 nM and a Bmax of 2.07 pmol/mg of protein. D-Serine, L-serine, and glycine produced a total inhibition of the specific DCK-insensitive D-[3H]serine binding to the cerebellum with similar Ki values. Strychnine and 7-chlorokynurenate failed to inhibit the binding at 10 microM. The profiles of displacement of the DCK-insensitive D-[3H]serine binding by various amino acids and glutamate and glycine receptor-related compounds differ from those of any other defined recognition sites. DCK-insensitive D-[3H]serine binding was at high levels in the cerebral cortex and cerebellum but very low in the kidney and liver. The present findings indicate that the DCK-insensitive D-[3H]serine binding site could be a novel candidate for a target for endogenous D-serine in mammalian brains.