Comparison of multiple parameters obtained on 3T pulsed arterial spin-labeling, diffusion tensor imaging, and MRS and the Ki-67 labeling index in evaluating glioma grading.

BACKGROUND AND PURPOSE: Pulsed arterial spin-labeling, DTI, and MR spectroscopy provide useful data for tumor evaluation. We evaluated multiple parameters by using these pulse sequences and the Ki-67 labeling index in newly diagnosed supratentorial gliomas. MATERIALS AND METHODS: All 32 patients, with grade II (3 each of diffuse astrocytoma, oligodendroglioma, and oligoastrocytoma), grade III (3 anaplastic astrocytomas, 4 anaplastic oligodendrogliomas, and 1 anaplastic oligoastrocytoma), and grade IV (14 glioblastomas and 1 glioblastoma with an oligodendroglioma component) cases underwent pulsed arterial spin-labeling, DTI, and MR spectroscopy studies by using 3T MR imaging. The following variables were used to compare the tumors: relative cerebral blood flow, fractional anisotropy; ADC tumor/normal ratios; and the Cho/Cr, NAA/Cho, NAA/Cr, and lactate/Cr ratios. A logistic regression and receiver operating characteristic analysis were used to assess parameters with a high sensitivity and specificity to identify the threshold values for separate grading. We compared the Ki-67 index with various MR imaging parameters in tumor specimens. RESULTS: Significant correlations were observed between the Ki-67 index and the mean, maximum, and minimum ADC, Cho/Cr, and lactate/Cr ratios. The receiver operating characteristic analysis showed that the combination of the minimum ADC and Cho/Cr ratios could differentiate low-grade and high-grade gliomas, with a sensitivity and specificity of 87.0% and 88.9%, respectively. The mean and maximum relative cerebral blood flow ratios were used to classify glioblastomas from other-grade astrocytomas, with a sensitivity and specificity of 92.9% and 83.3%, respectively. CONCLUSIONS: Our findings indicate that pulsed arterial spin-labeling, DTI, and MR spectroscopy are useful for predicting glioma grade. Additionally, the parameters obtained on DTI and MR spectroscopy closely correlated with the proliferative potential of gliomas.

Measurements of electron-induced neutrons as a tool for determination of electron temperature of fast electrons in the task of optimization laser-produced plasma ions acceleration.

High intensity laser-plasma interaction has attracted considerable interest for a number of years. The laser-plasma interaction is accompanied by generation of various charged particle beams, such as high-energy proton and ions with high charge to mass ratio (Q/M; same as multi-charged ions). Results of simultaneous novel measurements of electron-induced photonuclear neutrons (photoneutron), which are a diagnostic of the laser-plasma interaction, are proposed to use for optimization of the laser-plasma ion generation. The proposed method is demonstrated by the laser irradiation with the intensity of 1 × 10(21) W/cm(2) on the metal foil target. The photoneutrons are measured by using NE213 liquid scintillation detectors. Heavy-ion signal is registered with the CR-39 track detector simultaneously. The measured signals of the electron-induced photoneutrons are well reproduced by using the Particle and Heavy Ion Transport code System. The results obtained provide useful approach for analyzing the various laser based ion beams.

Multi-charged heavy ion acceleration from the ultra-intense short pulse laser system interacting with the metal target.

Experimental demonstration of multi-charged heavy ion acceleration from the interaction between the ultra-intense short pulse laser system and the metal target is presented. Al ions are accelerated up to 12 MeV/u (324 MeV total energy). To our knowledge, this is far the highest energy ever reported for the case of acceleration of the heavy ions produced by the <10 J laser energy of 200 TW class Ti:sapphire laser system. Adding to that, thanks to the extraordinary high intensity laser field of ∼10(21) W cm(-2), the accelerated ions are almost fully stripped, having high charge to mass ratio (Q/M).

Insertable pulse cleaning module with a saturable absorber pair and a compensating amplifier for high-intensity ultrashort-pulse lasers.

We demonstrate the performance of an efficient insertable pulse cleaning module (IPCM) that uses a saturable absorber (SA) pair with a compensating multi-pass amplifier. IPCM consists of a first SA, a grating compressor, a second SA, a stretcher and a compensating Ti:sapphire amplifier. It is implemented with a conventional chirped pulse amplification (CPA) Ti:sapphire laser system, resulting in a double CPA system architecture, and suppresses the amplified spontaneous emission (ASE) level of the pulse pedestal by about three orders of magnitude while preserving the output pulse energy and repetition-rate of the overall laser system. The duration of recompressed cleaned pulses is comparable to that obtained without the cleaning module. The effectiveness of the cleaning module is confirmed in laser-driven proton acceleration experiments. At the 10(9) W/cm2 pedestal level, the surface structure and electrical resistivity of an insulator target (100 nm silicon nitride) are preserved prior to the arrival of the intense ultrashort pulse.

Efficient multi-keV x-ray generation from a high-Z target irradiated with a clean ultra-short laser pulse.

Kα line emissions from Mo and Ag plates were experimentally studied using clean, ultrahigh-intensity femtosecond laser pulses. The absolute yields of Kα x-rays at 17 keV from Mo and 22 keV from Ag were measured as a function of the laser pulse contrast ratio and irradiation intensity. Significantly enhanced Kα yields were obtained for both Mo and Ag by employing high contrast ratios and irradiances. Conversion efficiencies of 4.28×10⁻5/sr for Mo and 4.84×10⁻5/sr for Ag, the highest values obtained to date, were demonstrated with contrast ratios in the range 10⁻¹° to 10⁻¹¹.

Synchronous and subsequent lesions of serrated adenomas and tubular adenomas of the colorectum.

The characteristics of synchronous and subsequent lesions of serrated adenomas (SAs) of the colorectum are still unclear. This study aimed to clarify the characteristics of synchronous and subsequent lesions of SAs compared with tubular adenomas (TAs) of the colorectum. Patients were divided into 2 groups: SA (127 patients) and TA (158 patients). The mean follow-up durations in the SA and TA groups were 39.7 and 42.7 months, respectively. The number and clinical features of the synchronous and subsequent lesions of both groups were examined. In the SA group, 19 (15%) patients had synchronous lesions and 3 (2%) patients had subsequent lesions. In the TA group, 68 (43%) patients had synchronous lesions and 14 (9%) patients had subsequent lesions. The frequencies of patients with synchronous and subsequent lesions in the SA group were significantly lower than those in the TA group (p < 0.0001 and p = 0.02, respectively). The most frequent synchronous lesion was SA (67%) in the SA group and TA (95%) in the TA group. The most subsequent lesion was SA (62%) in the SA group and TA (100%) in the TA group. The histology of the index polyp and synchronous and subsequent lesions tended to be identical. No invasive colorectal carcinomas were observed in either group. Our data suggest that the colonic tumorigenesis potential of patients with SA may differ from that of patients with TA.

High temporal and spatial quality petawatt-class Ti:sapphire chirped-pulse amplification laser system.

Optical parametric chirped-pulse amplification (OPCPA) operation with low gain by seeding with high-energy, clean pulses is shown to significantly improve the contrast to better than 10(-10) to 10(-11) in a high-intensity Ti:sapphire laser system that is based on chirped-pulse amplification. In addition to the high-contrast broadband, high-energy output from the final amplifier is achieved with a flat-topped spatial profile of filling factor near 77%. This is the result of pump beam spatial profile homogenization with diffractive optical elements. Final pulse energies exceed 30 J, indicating capability for reaching peak powers in excess of 500 TW.

Visceral fat accumulation is a significant risk factor for white matter lesions in Japanese type 2 diabetic patients.

BACKGROUND: The presence of white matter lesions (WML) is an important prognostic factor for the development of stroke. The elevated visceral fat accumulation (VFA) has been reported to be closely related to the development of atherosclerosis. This preliminary study was therefore designed to test the hypothesis that the presence of WML correlates with VFA and insulin resistance in type 2 diabetic patients not receiving insulin treatment. MATERIAL AND METHODS: Based on brain magnetic resonance imaging (MRI), 95 type 2 diabetic patients were divided into two groups: WML-positive group (aged 59 +/- 7 years, mean +/- SD n = 37) and WML-negative group (aged 58 +/- 5, years, n = 58). The level of blood glucose was assessed by fasting plasma glucose (FPG), fasting immunoreactive insulin, homeostasis model assessment (HOMA) index, and haemoglobin A1c. The fat distribution was evaluated by measuring the visceral fat accumulation by abdominal computerized tomography at the umbilical level. RESULTS: The body mass index was higher in the WML-positive group than in the WML-negative group (P < 0.005). Plasma levels of triglycerides were higher while high-density lipoprotein cholesterol was lower in the WML-positive group than in the WML-negative group (P < 0.05 and P < 0.01, respectively). FPG (P < 0.01), insulin concentrations (P < 0.0001), HOMA index (P < 0.0001) and VFA (<0.0001) levels were higher in the WML-positive group than in the WML-negative group. Multivariate logistic analysis revealed that WML was independently predicted by the high VFA and insulin resistance (P < 0.001, P < 0.0001, respectively). CONCLUSIONS: The results of this preliminary study indicate that the presence of WML was associated with the high VFA and insulin resistance in Japanese patients with type 2 diabetes mellitus. Further larger cohort studies are warranted to confirm these findings.

Electron optical injection with head-on and countercrossing colliding laser pulses.

A high stability electron bunch is generated by laser wakefield acceleration with the help of a colliding laser pulse. The wakefield is generated by a laser pulse; the second laser pulse collides with the first pulse at 180 degrees and at 135 degrees realizing optical injection of an electron bunch. The electron bunch has high stability and high reproducibility compared with single pulse electron generation. In the case of 180 degrees collision, special measures have been taken to prevent damage. In the case of 135 degrees collision, since the second pulse is countercrossing, it cannot damage the laser system.

Development of a compact optical system for microarray scanning using a DVD pickup head.

We present a compact optical system using a commercially available DVD pickup head for microarray scanning. Our instrument successfully provides a low-cost, compact, and simple microarray scanning optical system in comparison to conventional ones due to the use of small-sized optical components and the implementation of a simple autofocusing system using an embedded voice coil motor. The performance of this system was validated by using a microarray slide with spots of fluorescent dyes. It was confirmed that our optical head performed satisfactorily and was suitable for practical use in microarray scanners. This result provides evidence of the superiority of our microarray scanning optical system over conventional ones because of its space-saving properties and cost effectiveness.

Hyperhomocysteinaemia is a significant risk factor for white matter lesions in Japanese type 2 diabetic patients.

The presence of white matter lesions (WML) is an important prognostic factor for the development of stroke. Plasma total homocysteine (tHcy), which increases with diabetes, has been flagged as a novel predictor for cerebrovascular events. We tested the hypothesis that the presence of WML correlates with tHcy and insulin resistance in type 2 diabetic patients not receiving insulin treatment. Based on brain magnetic resonance imaging findings, 81 type 2 diabetic patients were divided into two groups, with-WML group (57 +/- 8 years, mean +/- standard deviation, n = 31) and without-WML group (57 +/- 6 years, n = 50). The blood glucose level was assessed by fasting plasma glucose (FPG), fasting immunoreactive insulin, Homeostasis Model Assessment (HOMA) Index and hemoglobin A1c. The body mass index was higher in the with-WML group than in the without-WML group (P < 0.05). Plasma levels of triglyceride were higher whilst high-density lipoprotein cholesterol was lower in the with-WML group than in the without-WML group (P < 0.05 and P < 0.0001 respectively). FPG (P < 0.005), insulin concentrations (P < 0.0001), HOMA Index (P < 0.0001) and tHcy (<0.0001) levels were higher in the with-WML group than in the without-WML group. Multivariate logistic analysis revealed that WML was independently predicted by the high tHcy and insulin resistance. Our findings indicate that the presence of WML was associated with the high tHcy and insulin resistance in these Japanese patients with type 2 diabetes mellitus.

Effect of rectal administration of rebamipide on dextran sulfate sodium-induced colitis: role of hepatocyte growth factor.

OBJECTIVE AND DESIGN: Since rebamipide is effective for the treatment of ulcerative colitis (UC), we examined the involvement of hepatocyte growth factor (HGF) in the action of rebamipide. MATERIALS: Fifty-five and forty female Balb/c mice, respectively, were used in Exp. 1 and 2. TREATMENT: 50 mg/kg/day rebamipide (Exp. 1) and 1 x 10(7) pfu pAxCAHGF (the CAG promoter-driving HGF gene in adenovirus vector) (Exp. 2) were intrarectally introduced after induction of colitis by 4 % dextran sulfate sodium (DSS). METHODS: Therapeutic effects were assessed by cell proliferation and apoptosis. RESULTS: Rebamipide caused proliferation of epithelial cells at 10 days after treatment, and decreased apoptosis at 10, 14 and 21 days, compared with controls. Expression of HGF was greatly increased in rebamipide-treated mice. pAxCAHGF caused cell proliferation and apoptosis, which showed the same pattern as with rebamipide treatment. CONCLUSIONS: Rectal administration of rebamipide is effective for DSS-induced colitis in association with induction of HGF.

Calcium pyrophosphate dihydrate deposition in the transverse ligament of the atlas: an unusual cause of cervical myelopathy.

A 75-year-old male presented with progressive myelopathy due to massive retro-odontoid deposits of calcium pyrophosphate dehydrate (CPPD) crystals. Magnetic resonance imaging revealed a non-enhanced isointense extradural mass on a T1-weighted image and a heterogeneous intense mass on a T2-weighted image. Computed tomography (CT) showed linear calcification within the mass. The mass was resected via a posterolateral approach resulting in marked improvement of the symptoms. Histological examination revealed birefringent rhomboid crystals consistent with CPPD. The preoperative differential diagnosis of periodontoid CPPD deposition disease in the elderly population should be considered, particularly if CT studies demonstrate small areas of calcification within the retro-odontoid mass.

Population dynamics of anaerobic microbial consortia in thermophilic methanogenic sludge treating paper-containing solid waste.

To maintain a stable thermophilic (55 degrees C) anaerobic digestion treating toilet paper-containing garbage, it is necessary to operate the digester at long hydraulic retention time (HRT) and low organic loading rate (OLR). Critical conditions of the digestion were investigated by operating the digester at HRT 23 days and OLR 3.4 gCOD(Cr)/L/d (R1) or HRT 14 days and OLR 5.6 gCOD/Cr)/L/d (R2) separately. Characteristics of methanogenesis of the two digesters were examined by measuring gas generation volume and volatile fatty acids (VFA) concentration, and the populations of four anaerobic acidogens and three methanogens were analyzed using quantitative PCR method. In digester R1, methanogenic activity was unstable but it could be recovered by stopping feeding as though VFA accumulation occurred. The population of acidogens and two methanogens were maintained at 10(11) - 10(13) copies/L, however, the population of Methanoculleus could not be recovered after methanogenesis recovering. In digester R2, the period of methanogenesis was significantly shorter than that in digester R1. Both the acidogens and the methanogens could not be maintained at a stable concentration. It is suggested that the critical HRT to sustain the population of acidogens in this process should be longer than 14 days and for all kinds of methanogens, HRT should be longer than 23 days.

[Extracorporeal membrane oxygenation for severe respiratory failure during thoracic aortic aneurysm repair].

We present a case of successful management for severe respiratory failure during thoracic aortic aneurysm repair by applying extracorporeal membrane oxygenation (ECMO). The patient was a 71-year-old man who was diagnosed as thoracic aortic aneurysm and coronary artery stenosis. Severe respiratory failure occurred during operation because of pulmonary hemorrhage, and it was difficult to wean from cardiopulmonary bypass. ECMO was provided for improvement of oxygenation and CO2 removal. Pulmonary hemorrhage was controlled by strict management of coagulation system, and ECMO was discontinued after improvement of oxygenation on the 4th postoperative day. It is considered that early application of ECMO was effective in this case.

[Surgery for acute aortic dissection concomitant with preceding axillofemoral bypass to prevent malperfusion of visceral organs and limb ischemia].

A 52-year-old man was admitted with sudden onset of epigastralgia. Abdominal X-ray showed dilated intestine and computed tomography (CT) revealed extended type A aortic dissection. Marked abdominal distention and weak pulse of right femoral artery were recognized so malperfusion of visceral organs due to narrowing true lumen compressed by thrombosed false lumen was suggested. In the operation, right axillo-right femoral bypass was established preceding to median sternotomy. This graft was used as an arterial perfusion site of cardiopulmonary bypass, and replacement of the ascending aorta was performed under hypothermic circulatory arrest and retrograde cerebral perfusion. Sign of malperfusion of visceral organs was showed for several days after the operation but it disappeared without further intervention. Axillofemoral inflow of cardiopulmonary bypass may be effective procedure in these cases.

[Successful treatment for tachyarrhythmia with ultra short acting beta-blocker during beating coronary artery bypass grafting; report of a case].

A 62-year-old man with supraventricular/ventricular tachycardia associated with myocardial infarction developed tachycardia during beating coronary artery bypass grafting (CABG). Intravenous administration of an ultra short acting beta-blocker, landiolol hydrochloride, controlled heart rate and improved tachyarrhythmia without significant change of blood pressure. Landiolol hydrochloride is effective and useful for the treatment of tachyarrhythmia during beating CABG.

Spontaneous regression of recurrent hepatocellular carcinoma after TAE: possible mechanisms of immune mediation.

We report findings in a 76-year-old man who underwent a lateral segmentectomy of the liver for hepatocellular carcinoma in July 1996. In July 1997, transarterial embolization (TAE) was performed for recurrent tumors in the remnant liver. Augmentation of the tumors and an increase in protein induced by vitamin K absence or antagonist (PIVKA)-II level were noted in October 1997, and, although we recommended TAE again, the patient and his family refused further treatment. Subsequently, the patient was only observed, and, except for a small lesion that was probably a scar, no tumors were noted on image examinations in November 1998, and the PIVKA-II level had returned to a normal value at this time. Two years after the regression, the tumors appeared to be in complete spontaneous remission. This patient had no history indicative of ischemic necrosis, and levels of cellular surface markers for natural killer (NK) cells and NK cell activity showed high values, which suggested that tumor immunity was activated by some, unknown, mechanism.

Involvement of Fc gamma receptor polymorphism in the therapeutic response of idiopathic thrombocytopenic purpura.

Clearance of autoantibody-sensitized platelets through Fc gamma receptors on phagocytic cells is one of the main mechanisms of thrombocytopenia in idiopathic thrombocytopenic purpura (ITP). We examined the Fc gamma RIIA-131R/H and Fc gamma RIIIA-158V/F polymorphisms in 104 adult chronic ITP patients, and in 59 healthy control subjects using polymerase chain reaction-based allele-specific restriction analysis. The frequency of Fc gamma RIIA genotypes (131H/H, H/R, R/R) was not significantly different between patients and controls, and did not correlate with the responsiveness to treatment. In contrast, among Fc gamma RIIIA genotypes, frequency of 158F/F homotype was smaller in ITP (P < 0.05). Furthermore, in Fc gamma RIIIA-158V/V homotype, the complete remission (CR) rate with medication (treatment with corticosteroid or other immunosuppressive agents) was significantly higher (60%) than that in 158V/F (10%) or 158V/F plus 158F/F, (P < 0.01, P < 0.05). Conversely, the CR rate after splenectomy in 158F/F and 158V/F types (64.3% and 54.6%) was higher than in 158V/V (25%). Our results indicate that the polymorphism of Fc gamma RIIIA, but not Fc gamma RIIA, influences the response to treatment in ITP.

Expression of hepatocyte growth factor activator and hepatocyte growth factor activator inhibitor type 1 in human hepatocellular carcinoma.

Hepatocyte growth factor activator inhibitor type 1 (HAI-1), a Kunitz-type serine protease inhibitor for hepatocyte growth factor activator (HGFA), is responsible for proteolytic activation of hepatocyte growth factor. We examined the expression of HGFA and HAI-1 in liver tissues of chronic liver diseases including hepatocellular carcinoma (HCC). HGFA expression was detected not only in the liver tissues of chronic hepatitis and cirrhosis and in the nontumorous liver tissues surrounding HCC, but also in HCC tissues. On the other hand, none of the liver tissues of hepatitis and cirrhosis and none of the nontumorous tissues surrounding HCC were stained with anti-HAI-1. However, 35% of HCC tissues were stained with anti-HAI-1, and HAI-1 positivity increased as the histological grade decreased and as serum alpha-fetoprotein increased. Transduction of antisense HAI-1 inhibited the growth of human hepatoma cells. These results suggest the possibility that HAI-1 plays an important role in the progression of HCC.